Total-Body 18F-FDG PET/CT: More Choices to Promote Clinical Scanning Efficiency

Total-Body 18F-FDG PET/CT: More Choices to Promote Clinical Scanning Efficiency | Research Square window.SnipcartSettings = { analytics: { enabled: false } }; (function() { var accessVector = localStorage.getItem('access_vector') || ''; window.dataLayer = window.dataLayer || []; if (accessVector) { window.dataLayer.push({ user: { profile: { profileInfo: { snid: accessVector } } } }); } })(); (function(w,d,s,l,i){w[l]=w[l]||[];w[l].push({'gtm.start':new Date().getTime(),event:'gtm.js'});var f=d.getElementsByTagName(s)[0],j=d.createElement(s),dl=l!='dataLayer'?'&l='+l:'';j.async=true;j.src='https://www.googletagmanager.com/gtm.js?id='+i+dl;f.parentNode.insertBefore(j,f);})(window,document,'script','dataLayer','GTM-K279D39R'); Browse Preprints In Review Journals COVID-19 Preprints AJE Video Bytes Research Tools Research Promotion AJE Professional Editing AJE Rubriq About Preprint Platform In Review Editorial Policies Our Team Advisory Board Help Center Sign In Submit a Preprint Cite Share Download PDF Research Article Total-Body 18F-FDG PET/CT: More Choices to Promote Clinical Scanning Efficiency Jie Xiao, Shuguang Chen, Xiaoguang Hou, Haojun Yu, Siwei Liu, and 5 more This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-6140160/v1 This work is licensed under a CC BY 4.0 License Status: Published Journal Publication published 02 Aug, 2025 Read the published version in EJNMMI Research → Version 1 posted 5 You are reading this latest preprint version Abstract Background The study aims to maximize clinical scan efficiency for Total-body (TB) 18 F-FDG PET/CT systems by optimizing scan strategies based on theoretical models and clinical experience from a single center. Results This prospective study include two parts. The first part involved simulation experiments using theoretical models to maximize patient throughput and/or minimizing radiotracer activity across four clinical scanning scenarios: fixed working time, predetermined radiotracer activity, integration of various injection dose regimens for a fixed number of patients, and incorporation of dynamic scans into routine static scans within a fixed working time. The optimal scan strategies for these scenarios were then proposed. The second part validated the estimated throughput results through high-throughput tests performed in the real clinical settings with an fixed working time of 8 hours. Under a fixed working time of 8 hours, the theoretical patient throughput for full-dose, half-dose, 1/3-dose, and 1/10-dose injection regimens was 60, 48, 43, 30 patients, respectively. The corresponding real clinical throughput achieved was 60, 49, 48, 28 patients. For a total 18 F-FDG activity of 37,000 to 148,000 MBq (1 to 4 Ci), the 1/3 dose injection regimen yielded the highest patient throughput, ranging 52 to 72 patients. Strategically combining various injection dose regimens could reduce radiotracer activity consumption. Additionally, placing full-dose dynamic scans after routine static scans for full-dose, half-dose, and 1/3 dose, and before 1/10 dose, proved to ba more economical strategies. Conclusions Optimized scan strategies for typical clinical scenarios of TB 18 F-FDG PET/CT systems were proposed, which could promote clinical scan efficiency and accommodate diverse clinical requirements. Total-body PET/CT Scan strategy Scanning efficiency 18F-FDG Throughput Figures Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 Figure 7 Background Over the past two decades, positron emission tomography/computed tomography (PET/CT) has evolved to cater to a wide range of clinical requirements, with 18 F-Fluorodeoxyglucose (FDG) remaining the most commonly used radiopharmaceutical [ 1 ]. In recent years, a major breakthrough in molecular imaging was achieved with the development of long-axial field-of-view (LAFOV) PET/CT scanners [ 2 ], which have proven superior to short AFOV PET/CT (SAFOV) due to their improved count collection efficiency [ 3 – 6 ]. Among the commercially available LAFOV scanners, uEXPLORER (United Imaging Healthcare) is the only system with an AFOV > 188 cm, covering from vertex to toes for 95% of the population in a single bed position, defined as total-body (TB) PET/CT [ 2 ]. In contrast, SAFOV PET/CT scanners (15–30 cm) usually require multiple-bed or multiple-pass imaging protocols to cover the patient from head to mid-thigh [ 7 – 9 ]. Clinical applications of 18 F-FDG TB PET/CT systems demonstrate improved image quality and lesion quantification due to higher sensitivity [ 10 ], alternatively allowing for a significant reduction in acquisition time or enabling low-dose examination protocols [ 11 , 12 ]. A study combining phantom and clinical investigations revealed that 30–45 seconds of acquisition time on TB PET/CT achieved equivalent image quality to 2–3 minutes per bed position on SAFOV scanners [ 13 ]. Furthermore, matched-pair analysis demonstrated that the TB PET/CT system can effectively perform cancer imaging using ultra-low doses, with successful scans at dose levels as low as 0.37 MBq/kg and an acquisition time of 8 minutes [ 14 ]. TB PET/CT thus offers advantages in meeting diverse clinical requirements compared to SAFOV systems, which typically require 15–25 minutes for whole-body imaging and 20–30 minutes for the entire scanning procedure per patient [ 15 ]. TB PET/CT provides greater flexibility in imaging acquisition protocols and customization for specific populations [ 16 – 21 ]. Expert consensus on 18 F-FDG TB PET/CT scanning protocols in oncology and workflow considerations for LAFOV PET/CT were proposed to enhance the clinical applications of these advanced devices [ 12 , 22 ]. Our center conducts PET/CT scans for more than 100 patients per workday. For departments like ours, which manage high workloads while accommoodating diverse individual demands, fully harnessing the potential of TB PET/CT and optimizing the efficiency of TB PET scanner remain challenging [ 23 ]. The workflow for TB 18 F-FDG PET/CT, including patient information acquisition, scheduling, instructions and precautions, and the examination procedure generally aligns with established guidelines [ 24 – 27 ]. However, additional cautions for the enhanced capabilities of TB PET/CT throughout the whole workflow are necessitated, which were detailed in the expert consensus [ 22 ]. Notably, establishing a reasonable scanning strategy before a day’s examination, taking into account factors such as patient throughput, total radiotracer activity consumption, total working time, and scan regimens, plays a critical role in maximizing the potential of TB PET/CT. This study aims to explore scan strategies to maximize clinical scan efficiency for TB 18 F-FDG PET/CT systems in typical clinical scenarios. The study first optimized the scan strategies for four clinical scanning scenarios based on theoretical models to either increase the patient throughputs or minimize the radiotracer activity consumption while maintaining the quality of the scans. Then the high-throughput tests within working time of 8 hours for different injection dose regiemes were performed in the real clinical settings to validation the robusteness of the therotical estimations. Methods TB 18 F-FDG PET/CT examination procedure and time comsumption The examination procedures for routine static and dynamic TB 18 F-FDG PET/CT scans are delineated in Fig. 1 . Drawing from extensive clinical scanning experience with TB 18 F-FDG PET/CT in our center [ 12 ], the average time each patient spends in the scanning room for full-dose (3.70MBq/kg), half-dose (1.85MBq/kg), 1/3-dose (1.11MBq/kg) and 1/10-dose (0.37MBq/kg) scans is about 8, 10, 11, 16 minutes, respectively. In detail, the total acquisition time for CT scans is about 1 minute, patient positioning and education is about 4 minutes, and average time required for a TB PET scan is approximately 3, 5, 6, and 11 minutes for full-dose, half-dose, 1/3 dose, and 1/10 dose scans, respectively. Similation experiment for scan strategy optimization The study provides a comprehensive analysis of four prevalent clinical scenarios of TB 18 F-FDG PET/CT scans, highlighting the imperative need for optimizing scan strategies (Fig. 2 ). Scenario 1: Given total working time, estimating the required 18 F-FDG activity dose and patient throughput under different injection dose regimens. Based on the exponential decay rule and the half-life of 18 F, and assuming a fixed injection dose regimen for all ordered patients after a single radiotracer preparation, the total activity consumption (in MBq) of 18 F-FDG can be estimated using Eq. 1 : $$\:A=k\times\:w\times\:\frac{1-{2}^{\frac{NT}{109.8}}}{1-{2}^{\frac{T}{109.8}}}$$ 1 Here, k represents the injection dose constant (activity per body weight in MBq/kg), \(\:w\) represents the population-average weight (in kg), N represents patient throughput, and \(\:T\) denotes the average time per patient spent in the scanning room. Given total working time ( NT ), the patient throughput ( N ) could be estimated by the empirical value of T for each injection dose regimen described above. Figure 3 a illustrates the relationship between the total working time and the number of patients for each injection dose regimen. Moreover, taking these empirical values of T and a world-average body weight value of 62 kg [ 28 ] into Eq. 1 , the total activity consumption (in MBq) for full-dose ( \(\:{A}_{Full}\) ), half-dose ( \(\:{A}_{Half}\) ), 1/3-dose ( \(\:{A}_{1/3}\) ) and 1/10-dose ( \(\:{A}_{1/10}\) ) scans can be described separately using Equations 2 , 3 , 4 , and 5 : $$\:{A}_{Full}=4428.6120\times\:({2}^{0.0729N}-1)$$ 2 $$\:{A}_{Half}=1760.1920\times\:({2}^{0.0911N}-1)$$ 3 $$\:{A}_{1/3}=957.0457\times\:({2}^{0.1002N}-1)$$ 4 $$\:{A}_{1/10}=215.8404\times\:({2}^{0.1457N}-1)$$ 5 Figure 3 b illustrates the relationship between the total activity consumption and the number of patients for each injection dose regimen. Scenario 2: Given a total 18 F-FDG activity, estimating patient throughput and required working time under different injection dose regimens. The estimation of the patient throughput ( N ) under different injection dose regimens can also be performed by Equations 2 – 4 . The corresponding working time ( NT ) can be estimated based on the empirical value of T for each injection dose regimen described above. Scenario 3: Given fixed number of patients, minimizing 18 F-FDG consumption through optimal integration of different injection dose regimens on a working day. An integration strategy involving various injection dose regimens can be optimized to minimize radiotracer activity consumption. The scanning process begins with \(\:{N}_{Full}\) patients with a full-dose regimen, followed by \(\:{N}_{Half}\) patients with a half-dose regimen, then \(\:{N}_{1/3}\) patients with a 1/3-dose regimen, and concludes with \(\:{N}_{1/10}\) patients with a 1/10-dose regimen. Here, \(\:{N}_{Full}+{N}_{Half}+{N}_{1/3}+{N}_{1/10}=N\) , representing the total number of ordered patients. The total activity consumption (in MBq) of 18 F-FDG for \(\:N\) ordered patients can be calculated using the Eq. 6 : $$\:A=2668.4200\times\:{2}^{0.0729{N}_{Full}}+803.1464\times\:{2}^{0.0729{N}_{Full}+0.09{11N}_{Half}}+741.2053\times\:{2}^{0.0729{N}_{Full}+0.0911{N}_{Half}+0.1002{N}_{1/3}}+215.8404\times\:{2}^{0.0729{N}_{Full}+0.0911{N}_{Half}+0.1002{N}_{1/3}+0.1457{N}_{1/10}}-4428.612$$ 6 Scenario 4: Given fixed working time, minimizing 18 F-FDG consumption through optimizing the scanning order for integrating dynamic and routine static scans. For the scenario have research demands in addition to fulfilling clinical scanning requirements, optimization efforts involve integrating dynamic and routine static scanning processes with appropriate order to minimize radiotracer activity consumption. In situations where a 60-min TB 18 F-FDG dynamic scan is needed, the total activity consumption \(\:({A}_{1dyn},\:\:\text{i}\text{n}\:\text{M}\text{B}\text{q}\) ) of 18 F-FDG can be estimated using Eq. 7 : $$\:{A}_{1dyn}=k\times\:w\times\:(\frac{1-{2}^{\frac{\left(i-1\right)T}{109.8}}}{1-{2}^{\frac{T}{109.8}}}+{2}^{\frac{\left(i-1\right)T+60}{109.8}}\times\:\frac{1-{2}^{\frac{\left(N-i\right)T}{109.8}}}{1-{2}^{\frac{T}{109.8}}})+{k{\prime\:}\times\:w\times\:2}^{\frac{\left(i-1\right)T}{109.8}}$$ 7 Here, k and \(\:k{\prime\:}\) represent the injection dose constants for the routine static scan and dynamic scan, respectively. \(\:w\) represents the population-average weight (in kg), \(\:T\) denotes the average time per patient with a routine static scan spent in the scanning room, N represents total number of patients that can be scanned in the fixed working time, and i is the scanning order of the dynamic scan. In the case where two 60-min TB 18 F-FDG dynamic scans are needed, the total activity consumption \(\:({A}_{2dyn},\:\:\text{i}\text{n}\:\text{M}\text{B}\text{q}\) ) of 18 F-FDG can be estimated using Eq. 8 : $$\:{A}_{2dyn}=k\times\:w\times\:(\frac{1-{2}^{\frac{\left(i-1\right)T}{109.8}}}{1-{2}^{\frac{T}{109.8}}}+{2}^{\frac{\left(i-1\right)T+60}{109.8}}\times\:\frac{1-{2}^{\frac{\left(j-i-1\right)T}{109.8}}}{1-{2}^{\frac{T}{109.8}}}+{2}^{\frac{\left(j-2\right)T+120}{109.8}}\times\:\frac{1-{2}^{\frac{\left(N-j\right)T}{109.8}}}{1-{2}^{\frac{T}{109.8}}})+{k{\prime\:}\times\:w\times\:(2}^{\frac{\left(i-1\right)T}{109.8}}+{2}^{\frac{\left(j-2\right)T+60}{109.8}})\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:$$ 8 Specifically, i is the scanning order of the first dynamic scan and j is the scanning order of the second dynamic scan ( i < j ). All simulation experiment for various scan strategies were performed by R software (version 4.1.0). Validation in clinical practice The high-throughput imaging tests for TB 18 F-FDG PET/CT examinations were conducted prospectively under the four injection dose regimens in May 2023. The scanning workflow and reconstruction protocal aligned with the procedure described above and the expert consensus [ 12 ]. Notably, the PET acquisition time was adjusted by patients' body mass index (BMI) for each injection dose regimen, as detailed in Table 1. The total working time was set at 8 hours. Additionally, an 8-hour high-throughput imaging test was conducted using a conventional PET/CT scanner (uMI 550, United Imaging Healthcare, Shanghai, China) with full-dose injection for comparison purpose. All patient information was collected following institutional ethical standards. Written informed consent was waived by all included patients before their recruitment into the study (Approval No. B2021-329). Results Theoretical Estimation and scan strategies optimization In the first scenario, when considering a fixed 8-hour workday, the patient throughput and total 18 F-FDG activity consumption for each injection dose regimen were presented in Table 2. The full-dose regimen yields the highest throughput of 60 patients, while the 1/10-dose regimen minimizes activity consumption to 4252.1 MBq (0.1149 Ci). In the second scenario with a fixed activity of 18 F-FDG, the patient throughput and total working time were shown in Table 3. For instance, if a total activity of 37,000 MBq (1 Ci) is available, the full-dose regimen allows scanning 44 patients within 5.87 hours, the half-dose regimen allows scanning 48 patients within 8.00 hours, and the 1/3-dose and 1/10-dose regimens enable scanning 52 patients within 9.53 hours and 50 patients within 13.33 hours, respectively. Notably, the 1/3-dose injection regimen achieved the highest patient throughput under the given activity of 37,000 to 148,000 MBq (1 to 4 Ci). In the third scenario, considering a fixed patient number of 50, there are 11 ways to integrate two, three, or four injection dose regimens to meet different clinical requirements, as listed in Table 4, with a total of 23,422 combination ways for injection dose regimen arrangements. A simulation experiment was performed to calculate the radiotracer activity consumption and total working time for each combination based on Eq. 7 . The minimal activity consumption for each integration way was searched, and the corresponding injection dose regimen combinations were summarized in Table 4. The results revealed that the total injection dose can be minimized to 17,049.6 MBq (0.4608 Ci) within a 10.33-hours working time which scans 9 patients with full-dose, followed by 3 patients with half-dose, 18 patients with 1/3-dose, and finally, 20 patients with 1/10-dose. Moreover, the total injection activity could be minimized to 25,874.1 MBq (0.6993 Ci) within an 8-hour working time by scanning 27 patients with full-dose, followed by 4 patients with half-dose, 16 patients with 1/3-dose, and finally, 3 patients with 1/10-dose (Table 5). Additionally, Fig. 4 a and Fig. 4 b depict the variation trend of total working time and activity consumption under different combinations of two dose regimens involving the full-dose injection and the other three dose regimens. Notably, the combination with 24 full-dose scans followed by 26 1/3-dose scans (the lowest point in the green dashed line in Fig. 4 b) demonstrated an optimal balance between activity consumption and total working time. In the fourth scenario, when a 60-minute full-dose dynamic scan is required within an 8-hour work time, the patient throughput of routine static scans within the remaining 7 hours is as follows: 52, 42, 38, and 26 for full, half, 1/3 and 1/10 dose injection regimens, respectively. The scanning order of the dynamic scan influences the total activity consumption, as illustrated in Fig. 5 . Reduction in total activity consumption was observed with the progressive postponement of the dynamic scan for full-dose, half-dose, and 1/3 dose regimen. The total radiotracer consumption was minimized by scheduling the dynamic scan at the end of the full-dose, half-dose, and 1/3-dose scanning sequences (Fig. 5 a, b, and c). Conversely, an increasing trend in total activity consumption was found in 1/10-dose injection regimen when postponing the dynamic scan. Conducting the dynamic scan at the beginning of the 1/10-dose scanning sequence minimized the total radiotracer consumption (Fig. 5 d). This pattern persists when considering two full-dose dynamic scans (Fig. 6 ). Placing both dynamic scans at the end of the scanning sequences for full-dose, half-dose, and 1/3-doseregimens results in the minimum total radiotracer consumption. For the 1/10-dose regimen, placing both dynamic scans at the beginning of the scanning sequences achieves the minimum total activity consumption (Fig. 6 d). Validation of patient throughput in clinical practice The actual patient throughputs within 8 hours, tested in the clinical settings with the uEXPLORER, were compared with the theoretical values estimated above (Table 5), which exhibit a close alignment. The actual average PET acquisition times per patient slightly deviated from the assumed average, and some differences were observed between the assumed and actual patient preparation time. All acquired PET images achieved acceptable image quality. In addition, the actual patient throughputs in 8 hours with full-dose regimen using uEXPLORER ( N = 60) was much higher than the uMI 550 ( N = 22), as expected. The reperesentive images illustrating the acceptable quality of PET scans obtained from the two devices are shown in Fig. 7 . Discussion The rising clinical demand for PET imaging highlights the critical need to optimize equipment utilization efficiency, a key factor in health economics. Conventional PET have limited capacity for improvement, as they can only expedite the examination by increasing the injection dose to a permissible limit. TB PET, on the other hand, offers transformative technical advantages, but the equipment is more costly. Improving the utilization efficiency of such equipment is thus of significant importance, and its superior performance unlocks numerous opportunities to improve scan efficientcy. This study is dedicated to advancing knowledge and solutions in this field. Drawing upon insights from our simulation-based optimization efforts, the following scan strategies were devised to enhance the clinical scan efficiency: (1) For the clinical scenario with a fixed total working hours of 8, needing to accommodate high patient throughput up to 60 patients on a workday, a full-dose injection regimen should be considered. When the scheduled patients were less than 60 on a workday, a combination of different injection regimens can also be utilized to save radiotracer consumption. (2) In the clinical scenario operating with a predetermined total radiotracer activity of 37,000 to 148,000 MBq (1 to 4 Ci), the 1/3-dose injection regimen affords the highest throughput potential, although this regimen is associated with prolonged total scan duration compared to the full-dose and half-dose injection regimens. (3) In the scenario with research demands of integrating one or two full-dose dynamic scans into routine static scans, these dynamic scans can be placed at the end of the scanning workflow for full-dose, half-dose, and 1/3-dose injection regimens, but at the beginning of the scan sequecce for 1/10-dose regimen to minimize the total activity consumption. These recommendations may serve as theoretical guidelines for designing scan strategies for clinical scanning scenarios with different requirements. Additionally, the high-throughput tests within 8 hours for full-dose, half-dose, 1/3-dose, and 1/10-dose injection regimens achieved throughput of 60, 49, 48, 28 patients, respectively, closely matching theoretical predicitons of 60, 48, 43, 30 patients. Fast scans with a full-dose injection regimen led to higher patient throughput which may be suitable for clinical sites burdened with heavy workloads. On the other hand, a low-dose regimen does not necessarily result in the lowest radiotracer consumption due to prolonged PET acquisition time and the exponential decay of radiotracers. As illustrated in Fig. 3 b, the 1/10-dose regimen consumes higher radiotracer activity when the patient number exceeds 46. Thus, an optimal combination of various injection regimens is advisible, not only to improve overall scan efficiency but also address diverse clinical requirements, such as utilizing the 1/10-dose regimen for pediatric patients. Additionally, in scenario requring full-dose dynamic scans, scheduling them at the beginning or end of the routine scans can reduces radiotracer consumption (Fig. 5 and Fig. 6 ) while minimizing disruptions to static scan workflow. The theoretical total activity consumption and patient throughput are estimated based on the prescribed population average weight and constant duration time spent in the scanning room. In real clinical practice, however, the items of actual individual radiotracer injection dose, patient preparation time, PET acquisition time, and continuity of scans may be influenced by many factors, such as variations in BMI, autonomous capacity of patient, and additional scanning needs. To validate the practicability of the therotical models, we performed the throughput tests in the context of real clinical settings with an 8-hour time frame for the four injection regimens and compared the results of them with the theoretical patient throughput estimated from the model and prescribed parameters. The results revealed relatively minor discrepancies between the theoretical and observed throughput, underscoring the model's robustness in accommodating population variance based on judiciously set up of appropriate parameters. This study focus on promoting scan efficiency and leveraging the potential of TB PET/CT by optimizing scan strategies. However, scan efficiency also depends on the smooth functioning of other aspects of the TB PET/CT workflow. For example, sufficient infrastructure and close staff cooperation are also critical, as discussed in prior article [ 22 ]. Moreover, as throughput tests shows, TB PET/CT nearly triples the number of patients scanned in 8 hours compared to conventional PET/CT system. In PET centers equipped with mutiple scanners, including but not limited to TB PET/CT, strategically selecting scanners based on clinical needs can further enhance overall efficiency. For instance, pediatric patients, fragile individuals, or those requiring a low-dose scan, fast scan, or comprehensive assessment of whole-body metabolic activity should be prioritized for TB PET/CT, leveraging its superior sensitivity and extended AFOV [ 16 – 18 ]. There are several limitations to consider in this study. Firstly, it is primarily a simulation-based investigation focused on harnessing the significant advantages of the TB PET/CT systems. While other long AFOV PET/CT devices also exhibit high physical performance and promising clinical benefits, scanning strategies optimization for these devices requires further exploration. Additionally, the estimation of radiotracer activity consumption is based on certain assumptions of model parameters, including a global average patient weight of 62 kg, and the established radiotracer injection regimen derived from the expert consensus [ 12 ]. It is crutial to recognize that patient populations vary significantly, and different clinical sites may have their own unique scanning procedures. Furthermore, the study only concentrated on clinical scanning procedures using 18 F-FDG due to its widespread usage. Adjustements to specific parameters are expected so that the theoretical models could be effectively adapted to different radiotracers, PET devices, and specific clinical requirements. Conclusion This study proposed optimized scan strategies with the minimal radiotracer consumption and/or the maximal patient throughput, promoting clinical scan efficiency for TB 18 F-FDG PET/CT and addressing diverse clinical requirements. The recommendations derived from our optimization results could offer valuable insights for long AFOV PET/CT scan arrangement in patient throughput estimation, integration of multiple scan regimens, and radiotracer preparation. Optimized scan strategies for typical clinical scenarios of TB 18 F-FDG PET/CT systems were proposed, which could promote clinical scan efficiency and accommodate diverse clinical requirements. Declarations Acknowledgements Not applicable. Author Contributions JX and SGC equally contributed to analyzing and interpreting data, and drafting the manuscript. XGH and HJY was responsible for acquisition data. SWL, TYG and GBL were responsible for image quality evaluation. QG and JYW processed the data. HCS contributed to conception and design the study, participated in data analysis, and approve the final content of the manuscript. All authors discussed the results and commented on the manuscript. Funding This study has received funding by the Innovative Medical Device Application Demonstration Program of Shanghai Municipal Commission of Economy and Informatization (grant number: 23SHS01200), the Key Program of Ministry of Industry and Information Technology of China (CEIEC-2022-ZM02-0219), the Chinese National Key Clinical Specialty Program (grant number: YWP2022-007), and the National Key Research and Development Program of China (grant number: 2022YFC2406902). Data availability The datasets generated during and/or analysed during the current study are available from the corresponding author on reasonable request. Code availability Not applicable. Ethics approval and consent to participate Institutional Review Board approval was obtained from Zhongshan Hospital, Fudan University, and informed consent was obtained from all individual participants included in the study. Consent for publication The requirement for informed consent was waived. Competing Interests Q.G. and J.W. are the employees of United Imaging Healthcare Co., Ltd., Shanghai, China. The remaining authors declare that they have no relevant financial or non-financial interests to disclose. References Rowe SP, Pomper MG. Molecular imaging in oncology: Current impact and future directions. CA Cancer J Clin. 2022;72(4):333-52. Mingels C, Caobelli F, Alavi A, et al. Total-body PET/CT or LAFOV PET/CT? Axial field-of-view clinical classification. Eur J Nucl Med Mol Imaging. 2024;51(4):951-3. Spencer BA, Berg E, Schmall JP, et al. Performance Evaluation of the uEXPLORER Total-Body PET/CT Scanner Based on NEMA NU 2-2018 with Additional Tests to Characterize PET Scanners with a Long Axial Field of View. J Nucl Med. 2021;62(6):861-70. Prenosil GA, Sari H, Fürstner M, et al. Performance Characteristics of the Biograph Vision Quadra PET/CT System with a Long Axial Field of View Using the NEMA NU 2-2018 Standard. J Nucl Med. 2022;63(3):476-84. Karp JS, Viswanath V, Geagan MJ, et al. PennPET Explorer: Design and Preliminary Performance of a Whole-Body Imager. J Nucl Med. 2020;61(1):136-43. Zhang H, Ren C, Liu Y, et al. Performance Characteristics of a New Generation 148-cm Axial Field-of-View uMI Panorama GS PET/CT System with Extended NEMA NU 2-2018 and EARL Standards. J Nucl Med. 2024;jnumed.124.267963. Filippi L, Dimitrakopoulou-Strauss A, Evangelista L, Schillaci O. Long axial field-of-view PET/CT devices: are we ready for the technological revolution? Expert Rev Med Devices. 2022;19(10):739-43. Acuff SN, Osborne D. Clinical Workflow Considerations for Implementation of Continuous-Bed-Motion PET/CT. J Nucl Med Technol. 2016;44(2):55-8. Yamashita S, Yamamoto H, Nakaichi T, Yoneyama T, Yokoyama K. Comparison of image quality between step-and-shoot and continuous bed motion techniques in whole-body (18)F-fluorodeoxyglucose positron emission tomography with the same acquisition duration. Ann Nucl Med. 2017;31(9):686-95. Mingels C, Chung KJ, Pantel AR, et al. Total-Body PET/CT: Challenges and Opportunities. Semin Nucl Med. 2024;S0001-2998(24)00076-X. Gu T, Liu S, Hou X, et al. Low dose optimization for total-body 2-[(18)F]FDG PET/CT imaging: a single-center study on feasibility based on body mass index stratification. Eur Radiol. 2024. Yu H, Gu Y, Fan W, et al. Expert consensus on oncological [18F] FDG total-body PET/CT imaging (version 1). European Radiology. 2023;33(1):615-26. Hu P, Zhang Y, Yu H, et al. Total-body 18 F-FDG PET/CT scan in oncology patients: how fast could it be? European journal of nuclear medicine and molecular imaging. 2021;48:2384-94. Hu Y, Liu G, Yu H, et al. Feasibility of Acquisitions Using Total-Body PET/CT with an Ultra-Low (18)F-FDG Activity. J Nucl Med. 2022;63(6):959-65. Vandenberghe S, Moskal P, Karp JS. State of the art in total body PET. EJNMMI Phys. 2020;7(1):35. Chen, W, Liu, L, Li, Y. et al. Evaluation of pediatric malignancies using total-body PET/CT with half-dose [18F]-FDG. Eur J Nucl Med Mol Imaging . 2022;49:4145–4155. Abdelhafez Y, Raychaudhuri SP, Mazza D, et al. Total-Body 18F-FDG PET/CT in Autoimmune Inflammatory Arthritis at Ultra-Low Dose: Initial Observations. J Nucl Med . 2022;63:1579-1585. Adili D, Cai D, Wu B, et al. An exploration of the feasibility and clinical value of half-dose 5-h total-body 18F-FDG PET/CT scan in patients with Takayasu arteritis. Eur J Nucl Med Mol Imaging. 2023;50:2375-2385. Tan H, Qi C, Cao Y, et al. Ultralow-dose [18F]FDG PET/CT imaging: demonstration of feasibility in dynamic and static images. Eur Radiol. 2023;33:5017-5027. Liu G, Xu H, Hu P, et al. Kinetic metrics of 18F-FDG in normal human organs identified by systematic dynamic total-body positron emission tomography. Eur J Nucl Med Mol Imaging. 2021;48:2363-2372. van Sluis J, Borra R, Tsoumpas C, et al. Extending the clinical capabilities of short- and long-lived positron-emitting radionuclides through high sensitivity PET/CT. Cancer Imaging. 2022;22:69. Liu G, Gu Y, Sollini M, et al. Expert consensus on workflow of PET/CT with long axial field-of-view. Eur J Nucl Med Mol Imaging. 2024. Chen WJ, Rae WID, Kench PL, et al. The potential advantages and workflow challenges of long axial field of view PET/CT. J Med Radiat Sc i . 2023;70:310-318. Boellaard R, Delgado-Bolton R, Oyen WJ, et al. FDG PET/CT: EANM procedure guidelines for tumour imaging: version 2.0. Eur J Nucl Med Mol Imaging. 2015;42:328-354. Vali R, Alessio A, Balza R, et al. SNMMI Procedure Standard/EANM Practice Guideline on Pediatric 18F-FDG PET/CT for Oncology 1.0. J Nucl Med. 2021;62:99-110. Dorbala S, Di Carli MF, Delbeke D, et al. SNMMI/ASNC/SCCT guideline for cardiac SPECT/CT and PET/CT 1.0. J Nucl Med. 2013;54:1485-1507. Guedj E, Varrone A, Boellaard R, et al. EANM procedure guidelines for brain PET imaging using [18F]FDG, version 3. Eur J Nucl Med Mol Imaging. 2022;49:632-651. The weight of nations: an estimation of adult human biomass. BMC Public Health . 2012;12:439. Tables Table 1. PET acquisition time (min) with 18 F-FDG TB PET/CT under four injection dose regimens in high-throughput imaging tests. BMI (kg, m 2 ) Full-dose Half-dose 1/3-dose 1/10-dose <25 3 4 5 10 25≤, <29 3 5 6 11 ≥29 3 7 8 12 Note: Full-dose means the injection dose was 3.7MBq/kg per patients. Table 2. Patient throughput and total 18 F-FDG activity consuption within 8 hours under the four injection dose regimens. Full-dose Half-dose 1/3-dose 1/10-dose Patient number 60 48 43 30 Total activity (×1000 MBq) 87.2453 34.6764 17.9978 4.2521 Table 3. Patient throughput and total working time with different total 18 F-FDG activity dose under the four injection dose regimens. Total activity (×1000 MBq) Full-dose Half-dose 1/3-dose 1/10-dose N T N T N T N T 37 44 5.87 48 8.00 52 9.53 50 13.33 74 56 7.47 59 9.83 62 11.37 57 15.20 111 64 8.53 65 10.83 68 12.47 61 16.27 148 70 9.33 70 11.67 72 13.20 64 17.07 Note: N, number of patient; T, total working time in hour Table 4 . Minimal total 18 F-FDG activity consumotion and combination of dose regimens for 50 patients in unlimited working time or a fixed working time of 8 hours. Total working time Minimal activity (×1000 MBq) Combination of 50 patients Type hour Full-dose Half-dose 1/3-dose 1/10-dose Unlimited time 7.63 35.0279 21 29 - - 8.32 26.1220 17 - 33 - 10.53 19.4102 21 - - 29 8.85 28.2606 - 19 31 - 10.83 18.7960 - 25 - 25 10.83 18.0671 - - 30 20 8.32 26.0961 16 3 31 - 10.50 18.1152 10 15 - 25 10.33 17.0681 10 - 20 20 10.63 17.5898 - 12 18 20 10.33 17.0496 9 3 18 20 within 8 hours 7.63 35.0279 21 29 - - 7.97 26.8250 24 - 26 - 8.00 31.8385 40 - - 10 8.00 26.6548 22 4 24 - 8.00 28.4863 28 16 - 6 7.98 26.0702 27 - 21 2 8.00 25.8741 27 4 16 3 Table 5. Comparison between the theoretical estimation and actual clinical validation results of patient throughput within 8 hours and the average time spent in the scanning room per patients under the four injection dose regimens. Full dose Half dose 1/3 dose 1/10 dose T Ac T Ac T Ac T Ac Age, years (Mean ± SD) - 59.9 ± 14.7 - 62.0 ± 11.4 - 61.6 ± 12.3 - 64.0 ± 9.5 Female (counts (percents)) - 24 (40.0%) - 17 (34.7%) - 18 (37.5%) - 12 (42.9%) Weight, kg - 63.1 ± 11.3 - 66.0 ± 10.8 - 65.7 ± 14.1 - 60.9± 9.2 BMI (Mean ± SD) - 23.0 ± 3.4 - 23.8 ± 3.1 - 23.8 ± 3.9 - 22.6 ± 3.0 PET acquisition time, minutes 3.00 3.00 5.00 4.51 6.00 5.55 11.00 10.20 CT acquisition time, minutes 1.00 1.13 1.00 1.11 1.00 1.14 1.00 1.13 Patient preparation time, minutes 4.00 3.63 4.00 4.37 4.00 2.50 4.00 4.21 Total time in the scanning room, minutes 8.00 8.00 10.00 9.79 11.00 10.00 16.00 17.14 Patient number 60 60 48 49 43 48 30 28 Note: T, theoretical value; Ac, actual value Cite Share Download PDF Status: Published Journal Publication published 02 Aug, 2025 Read the published version in EJNMMI Research → Version 1 posted Editorial decision: Minor Revision 22 May, 2025 Reviewers agreed at journal 31 Mar, 2025 Reviewers invited by journal 28 Mar, 2025 Editor assigned by journal 10 Mar, 2025 First submitted to journal 06 Mar, 2025 You are reading this latest preprint version Research Square lets you share your work early, gain feedback from the community, and start making changes to your manuscript prior to peer review in a journal. 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Also discoverable on Platform About Our Team In Review Editorial Policies Advisory Board Help Center Resources Author Services Accessibility API Access RSS feed Manage Cookie Preferences © Research Square 2026 | ISSN 2693-5015 (online) Privacy Policy Terms of Service Do Not Sell My Personal Information {"props":{"pageProps":{"initialData":{"identity":"rs-6140160","acceptedTermsAndConditions":true,"allowDirectSubmit":false,"archivedVersions":[],"articleType":"Research Article","associatedPublications":[],"authors":[{"id":435201720,"identity":"bd80c794-094c-4e5a-b6f3-ea9bea4578da","order_by":0,"name":"Jie Xiao","email":"data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAZAAAAAyAQMAAABI0h/eAAAABlBMVEX///8AAABVwtN+AAAACXBIWXMAAA7EAAAOxAGVKw4bAAAA4ElEQVRIiWNgGAWjYDACZiCWMGBgYG9IYHyQUFFDghaeAwnMBg/OHCPBNqAWNsmHLcyEVRocZ374wKLAhoGHPcesIrGBjYG/vTsBrxbJZjZjAwmDNAYenjdmNxJ3yDBInDm7Aa8WfmYGMwkJg8MM9hI5QC1n2BgMJHLxa2FjZv8G1PKfgQeopSCxjZmwFn5mHpAtB8BaGIjSItnMUwz0SzLQL8+KJRLOHOMh6BeD88c3Ppb4YwcMseSNH39U1Mjxt/fi1wICzBIMDPUNUA4PQeUgwPiBKGWjYBSMglEwYgEA7d09ozAkW9gAAAAASUVORK5CYII=","orcid":"","institution":"Zhongshan Hospital Fudan University","correspondingAuthor":true,"prefix":"","firstName":"Jie","middleName":"","lastName":"Xiao","suffix":""},{"id":435201721,"identity":"49448e6e-857c-43e6-af90-3cb9ce31bccc","order_by":1,"name":"Shuguang Chen","email":"","orcid":"","institution":"Zhongshan Hospital Fudan University","correspondingAuthor":false,"prefix":"","firstName":"Shuguang","middleName":"","lastName":"Chen","suffix":""},{"id":435201722,"identity":"c93359ac-54be-4475-8e10-9391302fa452","order_by":2,"name":"Xiaoguang Hou","email":"","orcid":"","institution":"Zhongshan Hospital Fudan University","correspondingAuthor":false,"prefix":"","firstName":"Xiaoguang","middleName":"","lastName":"Hou","suffix":""},{"id":435201723,"identity":"d84eaf76-e08e-4fd9-8af7-85c0ddf2d10a","order_by":3,"name":"Haojun Yu","email":"","orcid":"","institution":"Zhongshan Hospital Fudan University","correspondingAuthor":false,"prefix":"","firstName":"Haojun","middleName":"","lastName":"Yu","suffix":""},{"id":435201724,"identity":"2f936256-5d29-420d-9d0b-6ab334c4d65c","order_by":4,"name":"Siwei Liu","email":"","orcid":"","institution":"Zhongshan Hospital Fudan University","correspondingAuthor":false,"prefix":"","firstName":"Siwei","middleName":"","lastName":"Liu","suffix":""},{"id":435201725,"identity":"57a66286-79ff-44ee-86dc-c9bb63ab0e34","order_by":5,"name":"Taoying Gu","email":"","orcid":"","institution":"Zhongshan Hospital Fudan University","correspondingAuthor":false,"prefix":"","firstName":"Taoying","middleName":"","lastName":"Gu","suffix":""},{"id":435201726,"identity":"b26786b1-692a-4268-b108-e8e5c4a7fd49","order_by":6,"name":"Guobing Liu","email":"","orcid":"","institution":"Zhongshan Hospital Fudan University","correspondingAuthor":false,"prefix":"","firstName":"Guobing","middleName":"","lastName":"Liu","suffix":""},{"id":435201727,"identity":"582704d5-b735-4855-935c-4429f9ca3b26","order_by":7,"name":"Qi Ge","email":"","orcid":"","institution":"Center research center, United imaging Healthcare Co. Ltd","correspondingAuthor":false,"prefix":"","firstName":"Qi","middleName":"","lastName":"Ge","suffix":""},{"id":435201728,"identity":"c35afeba-8f1e-49cc-be08-fdcd13724a41","order_by":8,"name":"Jingyi Wang","email":"","orcid":"","institution":"United imaging Healthcare Co.Ltd","correspondingAuthor":false,"prefix":"","firstName":"Jingyi","middleName":"","lastName":"Wang","suffix":""},{"id":435201729,"identity":"296af397-4183-49c9-a240-b03b2668cc39","order_by":9,"name":"Hongcheng Shi","email":"","orcid":"","institution":"Zhongshan Hospital Fudan University","correspondingAuthor":false,"prefix":"","firstName":"Hongcheng","middleName":"","lastName":"Shi","suffix":""}],"badges":[],"createdAt":"2025-03-02 15:11:25","currentVersionCode":1,"declarations":"","doi":"10.21203/rs.3.rs-6140160/v1","doiUrl":"https://doi.org/10.21203/rs.3.rs-6140160/v1","draftVersion":[],"editorialEvents":[{"content":"https://doi.org/10.1186/s13550-025-01290-y","type":"published","date":"2025-08-02T16:05:28+00:00"}],"editorialNote":"","failedWorkflow":false,"files":[{"id":79810611,"identity":"22f49adf-1596-4c70-8469-4b6d91210d14","added_by":"auto","created_at":"2025-04-03 06:31:33","extension":"png","order_by":1,"title":"Figure 1","display":"","copyAsset":false,"role":"figure","size":43255,"visible":true,"origin":"","legend":"\u003cp\u003eTB PET/CT examination procedure for routine static scan \u003cstrong\u003e(a) \u003c/strong\u003eand dynamic scan \u003cstrong\u003e(b)\u003c/strong\u003e.\u003c/p\u003e","description":"","filename":"image1.png","url":"https://assets-eu.researchsquare.com/files/rs-6140160/v1/18d290bf0ca32ed539445e98.png"},{"id":79810612,"identity":"20ee47a1-c712-4740-99e4-fe80b32330fc","added_by":"auto","created_at":"2025-04-03 06:31:33","extension":"png","order_by":2,"title":"Figure 2","display":"","copyAsset":false,"role":"figure","size":32131,"visible":true,"origin":"","legend":"\u003cp\u003eFour typical clinical scenarios.\u003c/p\u003e","description":"","filename":"image2.png","url":"https://assets-eu.researchsquare.com/files/rs-6140160/v1/696a5d648eeaa5abf06854b8.png"},{"id":79810617,"identity":"06cb16fa-2e13-404e-8f0a-0130947c7ef3","added_by":"auto","created_at":"2025-04-03 06:31:33","extension":"png","order_by":3,"title":"Figure 3","display":"","copyAsset":false,"role":"figure","size":103342,"visible":true,"origin":"","legend":"\u003cp\u003eThe relationship between total working time and patient numbers under the four injection dose regimens \u003cstrong\u003e(a)\u003c/strong\u003e. The relationship between total \u003csup\u003e18\u003c/sup\u003eF-FDG activity consuption and patient numbers under the four injection dose regimens \u003cstrong\u003e(b)\u003c/strong\u003e.\u003c/p\u003e","description":"","filename":"image3.png","url":"https://assets-eu.researchsquare.com/files/rs-6140160/v1/dad932305e3ce0a435e45e1e.png"},{"id":79810616,"identity":"90667b7d-b8c0-4117-9c75-542349409614","added_by":"auto","created_at":"2025-04-03 06:31:33","extension":"png","order_by":4,"title":"Figure 4","display":"","copyAsset":false,"role":"figure","size":173076,"visible":true,"origin":"","legend":"\u003cp\u003eTotal working time \u003cstrong\u003e(a)\u003c/strong\u003e and total \u003csup\u003e18\u003c/sup\u003eF-FDG activity consumption \u003cstrong\u003e(b)\u003c/strong\u003e for combinations involving the full-dose and half-dose (blue dashed line), full-dose and 1/3-dose (green dashed line), and full-dose and 1/10-dose regimens (yellow dashed line).\u003c/p\u003e","description":"","filename":"image4.png","url":"https://assets-eu.researchsquare.com/files/rs-6140160/v1/d6c34c5a7eca50d2f962be54.png"},{"id":79810618,"identity":"cc099048-ee1b-458d-9e43-d5b2445f48f2","added_by":"auto","created_at":"2025-04-03 06:31:33","extension":"png","order_by":5,"title":"Figure 5","display":"","copyAsset":false,"role":"figure","size":173836,"visible":true,"origin":"","legend":"\u003cp\u003eTotal \u003csup\u003e18\u003c/sup\u003eF-FDG activity consumption within 8 hours for scenarios involving one full-dose dynamic scan with different scanning order in full-dose routine static scans \u003cstrong\u003e(a)\u003c/strong\u003e, or half-dose routine static scans \u003cstrong\u003e(b)\u003c/strong\u003e, or 1/3-dose routine static scans \u003cstrong\u003e(c)\u003c/strong\u003e, or 1/10-dose routine static scans \u003cstrong\u003e(d)\u003c/strong\u003e.\u003c/p\u003e","description":"","filename":"image5.png","url":"https://assets-eu.researchsquare.com/files/rs-6140160/v1/80d6a48490e92233d19d3e62.png"},{"id":79811351,"identity":"5be4293d-1d0f-4186-a997-a18a7e31051c","added_by":"auto","created_at":"2025-04-03 06:39:33","extension":"png","order_by":6,"title":"Figure 6","display":"","copyAsset":false,"role":"figure","size":257787,"visible":true,"origin":"","legend":"\u003cp\u003eTotal \u003csup\u003e18\u003c/sup\u003eF-FDG activity consumption within 8 hours for scenarios involving two full-dose dynamic scans with different scanning order in the full-dose routine static scans \u003cstrong\u003e(a)\u003c/strong\u003e, or half-dose routine static scans \u003cstrong\u003e(b)\u003c/strong\u003e, or 1/3-dose routine static scans \u003cstrong\u003e(c)\u003c/strong\u003e, or 1/10-dose routine static scans \u003cstrong\u003e(d)\u003c/strong\u003e. The x and y axes represent the scanning order of the first dynamic scan and the second dynamic scan, respectively.\u003c/p\u003e","description":"","filename":"image6.png","url":"https://assets-eu.researchsquare.com/files/rs-6140160/v1/27aeb1c35cee9601a20a3a03.png"},{"id":79811631,"identity":"e2a9a939-0a90-47fa-9d58-af5b57e70103","added_by":"auto","created_at":"2025-04-03 06:47:33","extension":"png","order_by":7,"title":"Figure 7","display":"","copyAsset":false,"role":"figure","size":383354,"visible":true,"origin":"","legend":"\u003cp\u003eA patient (BMI = 27.1 kg/m\u003csup\u003e2\u003c/sup\u003e) of carcinoma of sigmoid with liver metastasis was injected with full-dose (3.7 MBq/kg) \u003csup\u003e18\u003c/sup\u003eF-FDG and scanned with uEXPLORER (\u003cstrong\u003ea\u003c/strong\u003e). A patient (BMI = 23.4 kg/m\u003csup\u003e2\u003c/sup\u003e) with ascending colon malignant tumor with liver metastasis was injected with full-dose (3.7 MBq/kg) \u003csup\u003e18\u003c/sup\u003eF-FDG and scanned with uMI 550 (\u003cstrong\u003eb\u003c/strong\u003e).\u003c/p\u003e","description":"","filename":"image7.png","url":"https://assets-eu.researchsquare.com/files/rs-6140160/v1/9c7d764d534465228a19d921.png"},{"id":88268223,"identity":"55c7f8e4-f91a-47ab-9249-3026c786b8eb","added_by":"auto","created_at":"2025-08-04 16:50:12","extension":"pdf","order_by":0,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":1940785,"visible":true,"origin":"","legend":"","description":"","filename":"manuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-6140160/v1/d7217fff-6a43-4c78-9bba-bc6275e89658.pdf"}],"financialInterests":"","formattedTitle":"Total-Body 18F-FDG PET/CT: More Choices to Promote Clinical Scanning Efficiency","fulltext":[{"header":"Background","content":"\u003cp\u003eOver the past two decades, positron emission tomography/computed tomography (PET/CT) has evolved to cater to a wide range of clinical requirements, with \u003csup\u003e18\u003c/sup\u003eF-Fluorodeoxyglucose (FDG) remaining the most commonly used radiopharmaceutical [\u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e]. In recent years, a major breakthrough in molecular imaging was achieved with the development of long-axial field-of-view (LAFOV) PET/CT scanners [\u003cspan citationid=\"CR2\" class=\"CitationRef\"\u003e2\u003c/span\u003e], which have proven superior to short AFOV PET/CT (SAFOV) due to their improved count collection efficiency [\u003cspan additionalcitationids=\"CR4 CR5\" citationid=\"CR3\" class=\"CitationRef\"\u003e3\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR6\" class=\"CitationRef\"\u003e6\u003c/span\u003e]. Among the commercially available LAFOV scanners, uEXPLORER (United Imaging Healthcare) is the only system with an AFOV\u0026thinsp;\u0026gt;\u0026thinsp;188 cm, covering from vertex to toes for 95% of the population in a single bed position, defined as total-body (TB) PET/CT [\u003cspan citationid=\"CR2\" class=\"CitationRef\"\u003e2\u003c/span\u003e]. In contrast, SAFOV PET/CT scanners (15\u0026ndash;30 cm) usually require multiple-bed or multiple-pass imaging protocols to cover the patient from head to mid-thigh [\u003cspan additionalcitationids=\"CR8\" citationid=\"CR7\" class=\"CitationRef\"\u003e7\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR9\" class=\"CitationRef\"\u003e9\u003c/span\u003e].\u003c/p\u003e \u003cp\u003eClinical applications of \u003csup\u003e18\u003c/sup\u003eF-FDG TB PET/CT systems demonstrate improved image quality and lesion quantification due to higher sensitivity [\u003cspan citationid=\"CR10\" class=\"CitationRef\"\u003e10\u003c/span\u003e], alternatively allowing for a significant reduction in acquisition time or enabling low-dose examination protocols [\u003cspan citationid=\"CR11\" class=\"CitationRef\"\u003e11\u003c/span\u003e, \u003cspan citationid=\"CR12\" class=\"CitationRef\"\u003e12\u003c/span\u003e]. A study combining phantom and clinical investigations revealed that 30\u0026ndash;45 seconds of acquisition time on TB PET/CT achieved equivalent image quality to 2\u0026ndash;3 minutes per bed position on SAFOV scanners [\u003cspan citationid=\"CR13\" class=\"CitationRef\"\u003e13\u003c/span\u003e]. Furthermore, matched-pair analysis demonstrated that the TB PET/CT system can effectively perform cancer imaging using ultra-low doses, with successful scans at dose levels as low as 0.37 MBq/kg and an acquisition time of 8 minutes [\u003cspan citationid=\"CR14\" class=\"CitationRef\"\u003e14\u003c/span\u003e]. TB PET/CT thus offers advantages in meeting diverse clinical requirements compared to SAFOV systems, which typically require 15\u0026ndash;25 minutes for whole-body imaging and 20\u0026ndash;30 minutes for the entire scanning procedure per patient [\u003cspan citationid=\"CR15\" class=\"CitationRef\"\u003e15\u003c/span\u003e]. TB PET/CT provides greater flexibility in imaging acquisition protocols and customization for specific populations [\u003cspan additionalcitationids=\"CR17 CR18 CR19 CR20\" citationid=\"CR16\" class=\"CitationRef\"\u003e16\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR21\" class=\"CitationRef\"\u003e21\u003c/span\u003e]. Expert consensus on \u003csup\u003e18\u003c/sup\u003eF-FDG TB PET/CT scanning protocols in oncology and workflow considerations for LAFOV PET/CT were proposed to enhance the clinical applications of these advanced devices [\u003cspan citationid=\"CR12\" class=\"CitationRef\"\u003e12\u003c/span\u003e, \u003cspan citationid=\"CR22\" class=\"CitationRef\"\u003e22\u003c/span\u003e].\u003c/p\u003e \u003cp\u003eOur center conducts PET/CT scans for more than 100 patients per workday. For departments like ours, which manage high workloads while accommoodating diverse individual demands, fully harnessing the potential of TB PET/CT and optimizing the efficiency of TB PET scanner remain challenging [\u003cspan citationid=\"CR23\" class=\"CitationRef\"\u003e23\u003c/span\u003e]. The workflow for TB \u003csup\u003e18\u003c/sup\u003eF-FDG PET/CT, including patient information acquisition, scheduling, instructions and precautions, and the examination procedure generally aligns with established guidelines [\u003cspan additionalcitationids=\"CR25 CR26\" citationid=\"CR24\" class=\"CitationRef\"\u003e24\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR27\" class=\"CitationRef\"\u003e27\u003c/span\u003e]. However, additional cautions for the enhanced capabilities of TB PET/CT throughout the whole workflow are necessitated, which were detailed in the expert consensus [\u003cspan citationid=\"CR22\" class=\"CitationRef\"\u003e22\u003c/span\u003e]. Notably, establishing a reasonable scanning strategy before a day\u0026rsquo;s examination, taking into account factors such as patient throughput, total radiotracer activity consumption, total working time, and scan regimens, plays a critical role in maximizing the potential of TB PET/CT.\u003c/p\u003e \u003cp\u003eThis study aims to explore scan strategies to maximize clinical scan efficiency for TB \u003csup\u003e18\u003c/sup\u003eF-FDG PET/CT systems in typical clinical scenarios. The study first optimized the scan strategies for four clinical scanning scenarios based on theoretical models to either increase the patient throughputs or minimize the radiotracer activity consumption while maintaining the quality of the scans. Then the high-throughput tests within working time of 8 hours for different injection dose regiemes were performed in the real clinical settings to validation the robusteness of the therotical estimations.\u003c/p\u003e"},{"header":"Methods","content":"\u003cdiv id=\"Sec3\" class=\"Section2\"\u003e\n \u003ch2\u003eTB \u003csup\u003e18\u003c/sup\u003eF-FDG PET/CT examination procedure and time comsumption\u003c/h2\u003e\n \u003cp\u003eThe examination procedures for routine static and dynamic TB \u003csup\u003e18\u003c/sup\u003eF-FDG PET/CT scans are delineated in Fig. \u003cspan class=\"InternalRef\"\u003e1\u003c/span\u003e. Drawing from extensive clinical scanning experience with TB \u003csup\u003e18\u003c/sup\u003eF-FDG PET/CT in our center [\u003cspan class=\"CitationRef\"\u003e12\u003c/span\u003e], the average time each patient spends in the scanning room for full-dose (3.70MBq/kg), half-dose (1.85MBq/kg), 1/3-dose (1.11MBq/kg) and 1/10-dose (0.37MBq/kg) scans is about 8, 10, 11, 16 minutes, respectively. In detail, the total acquisition time for CT scans is about 1 minute, patient positioning and education is about 4 minutes, and average time required for a TB PET scan is approximately 3, 5, 6, and 11 minutes for full-dose, half-dose, 1/3 dose, and 1/10 dose scans, respectively.\u003c/p\u003e\n\u003c/div\u003e\n\u003ch3\u003eSimilation experiment for scan strategy optimization\u003c/h3\u003e\n\u003cp\u003eThe study provides a comprehensive analysis of four prevalent clinical scenarios of TB \u003csup\u003e18\u003c/sup\u003eF-FDG PET/CT scans, highlighting the imperative need for optimizing scan strategies (Fig. \u003cspan class=\"InternalRef\"\u003e2\u003c/span\u003e).\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eScenario 1:\u0026nbsp;\u003c/strong\u003eGiven total working time, estimating the required \u003csup\u003e18\u003c/sup\u003eF-FDG activity dose and patient throughput under different injection dose regimens.\u003c/p\u003e\n\u003cp\u003eBased on the exponential decay rule and the half-life of \u003csup\u003e18\u003c/sup\u003eF, and assuming a fixed injection dose regimen for all ordered patients after a single radiotracer preparation, the total activity consumption (in MBq) of \u003csup\u003e18\u003c/sup\u003eF-FDG can be estimated using Eq. \u003cspan class=\"InternalRef\"\u003e1\u003c/span\u003e:\u003c/p\u003e\n\u003cdiv id=\"Equ1\" class=\"Equation\"\u003e\n \u003cdiv class=\"mathdisplay\" id=\"FileID_Equ1\" name=\"EquationSource\"\u003e$$\\:A=k\\times\\:w\\times\\:\\frac{1-{2}^{\\frac{NT}{109.8}}}{1-{2}^{\\frac{T}{109.8}}}$$\u003c/div\u003e\n \u003cdiv class=\"EquationNumber\"\u003e1\u003c/div\u003e\n\u003c/div\u003e\n\u003cp\u003eHere, \u003cem\u003ek\u003c/em\u003e represents the injection dose constant (activity per body weight in MBq/kg), \u003cspan class=\"InlineEquation\"\u003e\u003cspan class=\"mathinline\"\u003e\\(\\:w\\)\u003c/span\u003e\u003c/span\u003e represents the population-average weight (in kg), \u003cem\u003eN\u003c/em\u003e represents patient throughput, and \u003cspan class=\"InlineEquation\"\u003e\u003cspan class=\"mathinline\"\u003e\\(\\:T\\)\u003c/span\u003e\u003c/span\u003e denotes the average time per patient spent in the scanning room. Given total working time (\u003cem\u003eNT\u003c/em\u003e), the patient throughput (\u003cem\u003eN\u003c/em\u003e) could be estimated by the empirical value of \u003cem\u003eT\u003c/em\u003e for each injection dose regimen described above. Figure \u003cspan class=\"InternalRef\"\u003e3\u003c/span\u003ea illustrates the relationship between the total working time and the number of patients for each injection dose regimen.\u003c/p\u003e\n\u003cp\u003eMoreover, taking these empirical values of \u003cem\u003eT\u003c/em\u003e and a world-average body weight value of 62 kg [\u003cspan class=\"CitationRef\"\u003e28\u003c/span\u003e] into Eq. \u003cspan class=\"InternalRef\"\u003e1\u003c/span\u003e, the total activity consumption (in MBq) for full-dose (\u003cspan class=\"InlineEquation\"\u003e\u003cspan class=\"mathinline\"\u003e\\(\\:{A}_{Full}\\)\u003c/span\u003e\u003c/span\u003e), half-dose (\u003cspan class=\"InlineEquation\"\u003e\u003cspan class=\"mathinline\"\u003e\\(\\:{A}_{Half}\\)\u003c/span\u003e\u003c/span\u003e), 1/3-dose (\u003cspan class=\"InlineEquation\"\u003e\u003cspan class=\"mathinline\"\u003e\\(\\:{A}_{1/3}\\)\u003c/span\u003e\u003c/span\u003e) and 1/10-dose (\u003cspan class=\"InlineEquation\"\u003e\u003cspan class=\"mathinline\"\u003e\\(\\:{A}_{1/10}\\)\u003c/span\u003e\u003c/span\u003e) scans can be described separately using Equations \u003cspan class=\"InternalRef\"\u003e2\u003c/span\u003e, \u003cspan class=\"InternalRef\"\u003e3\u003c/span\u003e, \u003cspan class=\"InternalRef\"\u003e4\u003c/span\u003e, and \u003cspan class=\"InternalRef\"\u003e5\u003c/span\u003e:\u003c/p\u003e\n\u003cdiv id=\"Equ2\" class=\"Equation\"\u003e\n \u003cdiv class=\"mathdisplay\" id=\"FileID_Equ2\" name=\"EquationSource\"\u003e$$\\:{A}_{Full}=4428.6120\\times\\:({2}^{0.0729N}-1)$$\u003c/div\u003e\n \u003cdiv class=\"EquationNumber\"\u003e2\u003c/div\u003e\n\u003c/div\u003e\n\u003cdiv id=\"Equ3\" class=\"Equation\"\u003e\n \u003cdiv class=\"mathdisplay\" id=\"FileID_Equ3\" name=\"EquationSource\"\u003e$$\\:{A}_{Half}=1760.1920\\times\\:({2}^{0.0911N}-1)$$\u003c/div\u003e\n \u003cdiv class=\"EquationNumber\"\u003e3\u003c/div\u003e\n\u003c/div\u003e\n\u003cdiv id=\"Equ4\" class=\"Equation\"\u003e\n \u003cdiv class=\"mathdisplay\" id=\"FileID_Equ4\" name=\"EquationSource\"\u003e$$\\:{A}_{1/3}=957.0457\\times\\:({2}^{0.1002N}-1)$$\u003c/div\u003e\n \u003cdiv class=\"EquationNumber\"\u003e4\u003c/div\u003e\n\u003c/div\u003e\n\u003cdiv id=\"Equ5\" class=\"Equation\"\u003e\n \u003cdiv class=\"mathdisplay\" id=\"FileID_Equ5\" name=\"EquationSource\"\u003e$$\\:{A}_{1/10}=215.8404\\times\\:({2}^{0.1457N}-1)$$\u003c/div\u003e\n \u003cdiv class=\"EquationNumber\"\u003e5\u003c/div\u003e\n\u003c/div\u003e\n\u003cp\u003eFigure \u003cspan class=\"InternalRef\"\u003e3\u003c/span\u003eb illustrates the relationship between the total activity consumption and the number of patients for each injection dose regimen.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eScenario 2:\u0026nbsp;\u003c/strong\u003eGiven a total \u003csup\u003e18\u003c/sup\u003eF-FDG activity, estimating patient throughput and required working time under different injection dose regimens.\u003c/p\u003e\n\u003cp\u003eThe estimation of the patient throughput (\u003cem\u003eN\u003c/em\u003e) under different injection dose regimens can also be performed by Equations \u003cspan class=\"InternalRef\"\u003e2\u003c/span\u003e\u0026ndash;\u003cspan class=\"InternalRef\"\u003e4\u003c/span\u003e. The corresponding working time (\u003cem\u003eNT\u003c/em\u003e) can be estimated based on the empirical value of \u003cem\u003eT\u003c/em\u003e for each injection dose regimen described above.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eScenario 3:\u0026nbsp;\u003c/strong\u003eGiven fixed number of patients, minimizing \u003csup\u003e18\u003c/sup\u003eF-FDG consumption through optimal integration of different injection dose regimens on a working day.\u003c/p\u003e\n\u003cp\u003eAn integration strategy involving various injection dose regimens can be optimized to minimize radiotracer activity consumption. The scanning process begins with \u003cspan class=\"InlineEquation\"\u003e\u003cspan class=\"mathinline\"\u003e\\(\\:{N}_{Full}\\)\u003c/span\u003e\u003c/span\u003e patients with a full-dose regimen, followed by \u003cspan class=\"InlineEquation\"\u003e\u003cspan class=\"mathinline\"\u003e\\(\\:{N}_{Half}\\)\u003c/span\u003e\u003c/span\u003e patients with a half-dose regimen, then \u003cspan class=\"InlineEquation\"\u003e\u003cspan class=\"mathinline\"\u003e\\(\\:{N}_{1/3}\\)\u003c/span\u003e\u003c/span\u003e patients with a 1/3-dose regimen, and concludes with \u003cspan class=\"InlineEquation\"\u003e\u003cspan class=\"mathinline\"\u003e\\(\\:{N}_{1/10}\\)\u003c/span\u003e\u003c/span\u003e patients with a 1/10-dose regimen. Here,\u003cspan class=\"InlineEquation\"\u003e\u003cspan class=\"mathinline\"\u003e\\(\\:{N}_{Full}+{N}_{Half}+{N}_{1/3}+{N}_{1/10}=N\\)\u003c/span\u003e\u003c/span\u003e, representing the total number of ordered patients. The total activity consumption (in MBq) of \u003csup\u003e18\u003c/sup\u003eF-FDG for \u003cspan class=\"InlineEquation\"\u003e\u003cspan class=\"mathinline\"\u003e\\(\\:N\\)\u003c/span\u003e\u003c/span\u003e ordered patients can be calculated using the Eq. \u003cspan class=\"InternalRef\"\u003e6\u003c/span\u003e:\u003c/p\u003e\n\u003cdiv id=\"Equ6\" class=\"Equation\"\u003e\n \u003cdiv class=\"mathdisplay\" id=\"FileID_Equ6\" name=\"EquationSource\"\u003e$$\\:A=2668.4200\\times\\:{2}^{0.0729{N}_{Full}}+803.1464\\times\\:{2}^{0.0729{N}_{Full}+0.09{11N}_{Half}}+741.2053\\times\\:{2}^{0.0729{N}_{Full}+0.0911{N}_{Half}+0.1002{N}_{1/3}}+215.8404\\times\\:{2}^{0.0729{N}_{Full}+0.0911{N}_{Half}+0.1002{N}_{1/3}+0.1457{N}_{1/10}}-4428.612$$\u003c/div\u003e\n \u003cdiv class=\"EquationNumber\"\u003e6\u003c/div\u003e\n\u003c/div\u003e\n\u003cp\u003e\u003cstrong\u003eScenario 4:\u0026nbsp;\u003c/strong\u003eGiven fixed working time, minimizing \u003csup\u003e18\u003c/sup\u003eF-FDG consumption through optimizing the scanning order for integrating dynamic and routine static scans.\u003c/p\u003e\n\u003cp\u003eFor the scenario have research demands in addition to fulfilling clinical scanning requirements, optimization efforts involve integrating dynamic and routine static scanning processes with appropriate order to minimize radiotracer activity consumption. In situations where a 60-min TB \u003csup\u003e18\u003c/sup\u003eF-FDG dynamic scan is needed, the total activity consumption\u003cspan class=\"InlineEquation\"\u003e\u003cspan class=\"mathinline\"\u003e\\(\\:({A}_{1dyn},\\:\\:\\text{i}\\text{n}\\:\\text{M}\\text{B}\\text{q}\\)\u003c/span\u003e\u003c/span\u003e) of \u003csup\u003e18\u003c/sup\u003eF-FDG can be estimated using Eq. \u003cspan class=\"InternalRef\"\u003e7\u003c/span\u003e:\u003c/p\u003e\n\u003cdiv id=\"Equ7\" class=\"Equation\"\u003e\n \u003cdiv class=\"mathdisplay\" id=\"FileID_Equ7\" name=\"EquationSource\"\u003e$$\\:{A}_{1dyn}=k\\times\\:w\\times\\:(\\frac{1-{2}^{\\frac{\\left(i-1\\right)T}{109.8}}}{1-{2}^{\\frac{T}{109.8}}}+{2}^{\\frac{\\left(i-1\\right)T+60}{109.8}}\\times\\:\\frac{1-{2}^{\\frac{\\left(N-i\\right)T}{109.8}}}{1-{2}^{\\frac{T}{109.8}}})+{k{\\prime\\:}\\times\\:w\\times\\:2}^{\\frac{\\left(i-1\\right)T}{109.8}}$$\u003c/div\u003e\n \u003cdiv class=\"EquationNumber\"\u003e7\u003c/div\u003e\n\u003c/div\u003e\n\u003cp\u003eHere, \u003cem\u003ek\u003c/em\u003e and \u003cspan class=\"InlineEquation\"\u003e\u003cspan class=\"mathinline\"\u003e\\(\\:k{\\prime\\:}\\)\u003c/span\u003e\u003c/span\u003erepresent the injection dose constants for the routine static scan and dynamic scan, respectively. \u003cspan class=\"InlineEquation\"\u003e\u003cspan class=\"mathinline\"\u003e\\(\\:w\\)\u003c/span\u003e\u003c/span\u003e represents the population-average weight (in kg), \u003cspan class=\"InlineEquation\"\u003e\u003cspan class=\"mathinline\"\u003e\\(\\:T\\)\u003c/span\u003e\u003c/span\u003e denotes the average time per patient with a routine static scan spent in the scanning room, \u003cem\u003eN\u003c/em\u003e represents total number of patients that can be scanned in the fixed working time, and \u003cem\u003ei\u003c/em\u003e is the scanning order of the dynamic scan.\u003c/p\u003e\n\u003cp\u003eIn the case where two 60-min TB \u003csup\u003e18\u003c/sup\u003eF-FDG dynamic scans are needed, the total activity consumption\u003cspan class=\"InlineEquation\"\u003e\u003cspan class=\"mathinline\"\u003e\\(\\:({A}_{2dyn},\\:\\:\\text{i}\\text{n}\\:\\text{M}\\text{B}\\text{q}\\)\u003c/span\u003e\u003c/span\u003e) of \u003csup\u003e18\u003c/sup\u003eF-FDG can be estimated using Eq.\u0026nbsp;\u003cspan class=\"InternalRef\"\u003e8\u003c/span\u003e:\u003c/p\u003e\n\u003cdiv id=\"Equ8\" class=\"Equation\"\u003e\n \u003cdiv class=\"mathdisplay\" id=\"FileID_Equ8\" name=\"EquationSource\"\u003e$$\\:{A}_{2dyn}=k\\times\\:w\\times\\:(\\frac{1-{2}^{\\frac{\\left(i-1\\right)T}{109.8}}}{1-{2}^{\\frac{T}{109.8}}}+{2}^{\\frac{\\left(i-1\\right)T+60}{109.8}}\\times\\:\\frac{1-{2}^{\\frac{\\left(j-i-1\\right)T}{109.8}}}{1-{2}^{\\frac{T}{109.8}}}+{2}^{\\frac{\\left(j-2\\right)T+120}{109.8}}\\times\\:\\frac{1-{2}^{\\frac{\\left(N-j\\right)T}{109.8}}}{1-{2}^{\\frac{T}{109.8}}})+{k{\\prime\\:}\\times\\:w\\times\\:(2}^{\\frac{\\left(i-1\\right)T}{109.8}}+{2}^{\\frac{\\left(j-2\\right)T+60}{109.8}})\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:$$\u003c/div\u003e\n \u003cdiv class=\"EquationNumber\"\u003e8\u003c/div\u003e\n\u003c/div\u003e\n\u003cp\u003eSpecifically, \u003cem\u003ei\u003c/em\u003e is the scanning order of the first dynamic scan and \u003cem\u003ej\u003c/em\u003e is the scanning order of the second dynamic scan (\u003cem\u003ei\u003c/em\u003e\u0026thinsp;\u0026lt;\u0026thinsp;\u003cem\u003ej\u003c/em\u003e).\u003c/p\u003e\n\u003cp\u003eAll simulation experiment for various scan strategies were performed by R software (version 4.1.0).\u003c/p\u003e\n\u003ch3\u003eValidation in clinical practice\u003c/h3\u003e\n\u003cp\u003eThe high-throughput imaging tests for TB \u003csup\u003e18\u003c/sup\u003eF-FDG PET/CT examinations were conducted prospectively under the four injection dose regimens in May 2023. The scanning workflow and reconstruction protocal aligned with the procedure described above and the expert consensus [\u003cspan class=\"CitationRef\"\u003e12\u003c/span\u003e]. Notably, the PET acquisition time was adjusted by patients\u0026apos; body mass index (BMI) for each injection dose regimen, as detailed in Table\u0026nbsp;1. The total working time was set at 8 hours. Additionally, an 8-hour high-throughput imaging test was conducted using a conventional PET/CT scanner (uMI 550, United Imaging Healthcare, Shanghai, China) with full-dose injection for comparison purpose.\u003c/p\u003e\n\u003cp\u003eAll patient information was collected following institutional ethical standards. Written informed consent was waived by all included patients before their recruitment into the study (Approval No. B2021-329).\u003c/p\u003e"},{"header":"Results","content":"\u003cdiv id=\"Sec7\" class=\"Section2\"\u003e \u003ch2\u003eTheoretical Estimation and scan strategies optimization\u003c/h2\u003e \u003cp\u003eIn the first scenario, when considering a fixed 8-hour workday, the patient throughput and total \u003csup\u003e18\u003c/sup\u003eF-FDG activity consumption for each injection dose regimen were presented in Table\u0026nbsp;2. The full-dose regimen yields the highest throughput of 60 patients, while the 1/10-dose regimen minimizes activity consumption to 4252.1 MBq (0.1149 Ci).\u003c/p\u003e \u003cp\u003eIn the second scenario with a fixed activity of \u003csup\u003e18\u003c/sup\u003eF-FDG, the patient throughput and total working time were shown in Table\u0026nbsp;3. For instance, if a total activity of 37,000 MBq (1 Ci) is available, the full-dose regimen allows scanning 44 patients within 5.87 hours, the half-dose regimen allows scanning 48 patients within 8.00 hours, and the 1/3-dose and 1/10-dose regimens enable scanning 52 patients within 9.53 hours and 50 patients within 13.33 hours, respectively. Notably, the 1/3-dose injection regimen achieved the highest patient throughput under the given activity of 37,000 to 148,000 MBq (1 to 4 Ci).\u003c/p\u003e \u003cp\u003eIn the third scenario, considering a fixed patient number of 50, there are 11 ways to integrate two, three, or four injection dose regimens to meet different clinical requirements, as listed in Table\u0026nbsp;4, with a total of 23,422 combination ways for injection dose regimen arrangements. A simulation experiment was performed to calculate the radiotracer activity consumption and total working time for each combination based on Eq.\u0026nbsp;\u003cspan refid=\"Equ7\" class=\"InternalRef\"\u003e7\u003c/span\u003e. The minimal activity consumption for each integration way was searched, and the corresponding injection dose regimen combinations were summarized in Table\u0026nbsp;4. The results revealed that the total injection dose can be minimized to 17,049.6 MBq (0.4608 Ci) within a 10.33-hours working time which scans 9 patients with full-dose, followed by 3 patients with half-dose, 18 patients with 1/3-dose, and finally, 20 patients with 1/10-dose. Moreover, the total injection activity could be minimized to 25,874.1 MBq (0.6993 Ci) within an 8-hour working time by scanning 27 patients with full-dose, followed by 4 patients with half-dose, 16 patients with 1/3-dose, and finally, 3 patients with 1/10-dose (Table\u0026nbsp;5). Additionally, Fig.\u0026nbsp;\u003cspan refid=\"Fig4\" class=\"InternalRef\"\u003e4\u003c/span\u003ea and Fig.\u0026nbsp;\u003cspan refid=\"Fig4\" class=\"InternalRef\"\u003e4\u003c/span\u003eb depict the variation trend of total working time and activity consumption under different combinations of two dose regimens involving the full-dose injection and the other three dose regimens. Notably, the combination with 24 full-dose scans followed by 26 1/3-dose scans (the lowest point in the green dashed line in Fig.\u0026nbsp;\u003cspan refid=\"Fig4\" class=\"InternalRef\"\u003e4\u003c/span\u003eb) demonstrated an optimal balance between activity consumption and total working time.\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003cp\u003eIn the fourth scenario, when a 60-minute full-dose dynamic scan is required within an 8-hour work time, the patient throughput of routine static scans within the remaining 7 hours is as follows: 52, 42, 38, and 26 for full, half, 1/3 and 1/10 dose injection regimens, respectively. The scanning order of the dynamic scan influences the total activity consumption, as illustrated in Fig.\u0026nbsp;\u003cspan refid=\"Fig5\" class=\"InternalRef\"\u003e5\u003c/span\u003e. Reduction in total activity consumption was observed with the progressive postponement of the dynamic scan for full-dose, half-dose, and 1/3 dose regimen. The total radiotracer consumption was minimized by scheduling the dynamic scan at the end of the full-dose, half-dose, and 1/3-dose scanning sequences (Fig.\u0026nbsp;\u003cspan refid=\"Fig5\" class=\"InternalRef\"\u003e5\u003c/span\u003ea, b, and c). Conversely, an increasing trend in total activity consumption was found in 1/10-dose injection regimen when postponing the dynamic scan. Conducting the dynamic scan at the beginning of the 1/10-dose scanning sequence minimized the total radiotracer consumption (Fig.\u0026nbsp;\u003cspan refid=\"Fig5\" class=\"InternalRef\"\u003e5\u003c/span\u003ed). This pattern persists when considering two full-dose dynamic scans (Fig.\u0026nbsp;\u003cspan refid=\"Fig6\" class=\"InternalRef\"\u003e6\u003c/span\u003e). Placing both dynamic scans at the end of the scanning sequences for full-dose, half-dose, and 1/3-doseregimens results in the minimum total radiotracer consumption. For the 1/10-dose regimen, placing both dynamic scans at the beginning of the scanning sequences achieves the minimum total activity consumption (Fig.\u0026nbsp;\u003cspan refid=\"Fig6\" class=\"InternalRef\"\u003e6\u003c/span\u003ed).\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec8\" class=\"Section2\"\u003e \u003ch2\u003eValidation of patient throughput in clinical practice\u003c/h2\u003e \u003cp\u003eThe actual patient throughputs within 8 hours, tested in the clinical settings with the uEXPLORER, were compared with the theoretical values estimated above (Table\u0026nbsp;5), which exhibit a close alignment. The actual average PET acquisition times per patient slightly deviated from the assumed average, and some differences were observed between the assumed and actual patient preparation time. All acquired PET images achieved acceptable image quality. In addition, the actual patient throughputs in 8 hours with full-dose regimen using uEXPLORER (\u003cem\u003eN\u003c/em\u003e\u0026thinsp;=\u0026thinsp;60) was much higher than the uMI 550 (\u003cem\u003eN\u003c/em\u003e\u0026thinsp;=\u0026thinsp;22), as expected. The reperesentive images illustrating the acceptable quality of PET scans obtained from the two devices are shown in Fig.\u0026nbsp;\u003cspan refid=\"Fig7\" class=\"InternalRef\"\u003e7\u003c/span\u003e.\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003c/div\u003e"},{"header":"Discussion","content":"\u003cp\u003eThe rising clinical demand for PET imaging highlights the critical need to optimize equipment utilization efficiency, a key factor in health economics. Conventional PET have limited capacity for improvement, as they can only expedite the examination by increasing the injection dose to a permissible limit. TB PET, on the other hand, offers transformative technical advantages, but the equipment is more costly. Improving the utilization efficiency of such equipment is thus of significant importance, and its superior performance unlocks numerous opportunities to improve scan efficientcy. This study is dedicated to advancing knowledge and solutions in this field. Drawing upon insights from our simulation-based optimization efforts, the following scan strategies were devised to enhance the clinical scan efficiency: (1) For the clinical scenario with a fixed total working hours of 8, needing to accommodate high patient throughput up to 60 patients on a workday, a full-dose injection regimen should be considered. When the scheduled patients were less than 60 on a workday, a combination of different injection regimens can also be utilized to save radiotracer consumption. (2) In the clinical scenario operating with a predetermined total radiotracer activity of 37,000 to 148,000 MBq (1 to 4 Ci), the 1/3-dose injection regimen affords the highest throughput potential, although this regimen is associated with prolonged total scan duration compared to the full-dose and half-dose injection regimens. (3) In the scenario with research demands of integrating one or two full-dose dynamic scans into routine static scans, these dynamic scans can be placed at the end of the scanning workflow for full-dose, half-dose, and 1/3-dose injection regimens, but at the beginning of the scan sequecce for 1/10-dose regimen to minimize the total activity consumption. These recommendations may serve as theoretical guidelines for designing scan strategies for clinical scanning scenarios with different requirements. Additionally, the high-throughput tests within 8 hours for full-dose, half-dose, 1/3-dose, and 1/10-dose injection regimens achieved throughput of 60, 49, 48, 28 patients, respectively, closely matching theoretical predicitons of 60, 48, 43, 30 patients.\u003c/p\u003e \u003cp\u003eFast scans with a full-dose injection regimen led to higher patient throughput which may be suitable for clinical sites burdened with heavy workloads. On the other hand, a low-dose regimen does not necessarily result in the lowest radiotracer consumption due to prolonged PET acquisition time and the exponential decay of radiotracers. As illustrated in Fig.\u0026nbsp;\u003cspan refid=\"Fig3\" class=\"InternalRef\"\u003e3\u003c/span\u003eb, the 1/10-dose regimen consumes higher radiotracer activity when the patient number exceeds 46. Thus, an optimal combination of various injection regimens is advisible, not only to improve overall scan efficiency but also address diverse clinical requirements, such as utilizing the 1/10-dose regimen for pediatric patients. Additionally, in scenario requring full-dose dynamic scans, scheduling them at the beginning or end of the routine scans can reduces radiotracer consumption (Fig.\u0026nbsp;\u003cspan refid=\"Fig5\" class=\"InternalRef\"\u003e5\u003c/span\u003e and Fig.\u0026nbsp;\u003cspan refid=\"Fig6\" class=\"InternalRef\"\u003e6\u003c/span\u003e) while minimizing disruptions to static scan workflow.\u003c/p\u003e \u003cp\u003eThe theoretical total activity consumption and patient throughput are estimated based on the prescribed population average weight and constant duration time spent in the scanning room. In real clinical practice, however, the items of actual individual radiotracer injection dose, patient preparation time, PET acquisition time, and continuity of scans may be influenced by many factors, such as variations in BMI, autonomous capacity of patient, and additional scanning needs. To validate the practicability of the therotical models, we performed the throughput tests in the context of real clinical settings with an 8-hour time frame for the four injection regimens and compared the results of them with the theoretical patient throughput estimated from the model and prescribed parameters. The results revealed relatively minor discrepancies between the theoretical and observed throughput, underscoring the model's robustness in accommodating population variance based on judiciously set up of appropriate parameters.\u003c/p\u003e \u003cp\u003eThis study focus on promoting scan efficiency and leveraging the potential of TB PET/CT by optimizing scan strategies. However, scan efficiency also depends on the smooth functioning of other aspects of the TB PET/CT workflow. For example, sufficient infrastructure and close staff cooperation are also critical, as discussed in prior article [\u003cspan citationid=\"CR22\" class=\"CitationRef\"\u003e22\u003c/span\u003e]. Moreover, as throughput tests shows, TB PET/CT nearly triples the number of patients scanned in 8 hours compared to conventional PET/CT system. In PET centers equipped with mutiple scanners, including but not limited to TB PET/CT, strategically selecting scanners based on clinical needs can further enhance overall efficiency. For instance, pediatric patients, fragile individuals, or those requiring a low-dose scan, fast scan, or comprehensive assessment of whole-body metabolic activity should be prioritized for TB PET/CT, leveraging its superior sensitivity and extended AFOV [\u003cspan additionalcitationids=\"CR17\" citationid=\"CR16\" class=\"CitationRef\"\u003e16\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR18\" class=\"CitationRef\"\u003e18\u003c/span\u003e].\u003c/p\u003e \u003cp\u003eThere are several limitations to consider in this study. Firstly, it is primarily a simulation-based investigation focused on harnessing the significant advantages of the TB PET/CT systems. While other long AFOV PET/CT devices also exhibit high physical performance and promising clinical benefits, scanning strategies optimization for these devices requires further exploration. Additionally, the estimation of radiotracer activity consumption is based on certain assumptions of model parameters, including a global average patient weight of 62 kg, and the established radiotracer injection regimen derived from the expert consensus [\u003cspan citationid=\"CR12\" class=\"CitationRef\"\u003e12\u003c/span\u003e]. It is crutial to recognize that patient populations vary significantly, and different clinical sites may have their own unique scanning procedures. Furthermore, the study only concentrated on clinical scanning procedures using \u003csup\u003e18\u003c/sup\u003eF-FDG due to its widespread usage. Adjustements to specific parameters are expected so that the theoretical models could be effectively adapted to different radiotracers, PET devices, and specific clinical requirements.\u003c/p\u003e"},{"header":"Conclusion","content":"\u003cp\u003eThis study proposed optimized scan strategies with the minimal radiotracer consumption and/or the maximal patient throughput, promoting clinical scan efficiency for TB \u003csup\u003e18\u003c/sup\u003eF-FDG PET/CT and addressing diverse clinical requirements. The recommendations derived from our optimization results could offer valuable insights for long AFOV PET/CT scan arrangement in patient throughput estimation, integration of multiple scan regimens, and radiotracer preparation. Optimized scan strategies for typical clinical scenarios of TB \u003csup\u003e18\u003c/sup\u003eF-FDG PET/CT systems were proposed, which could promote clinical scan efficiency and accommodate diverse clinical requirements.\u003c/p\u003e"},{"header":"Declarations","content":"\u003cp\u003e\u003cstrong\u003eAcknowledgements\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eNot applicable.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eAuthor Contributions\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eJX and SGC equally contributed to analyzing and interpreting data, and drafting the manuscript. XGH and HJY was responsible for acquisition data. SWL, TYG and GBL were responsible for image quality evaluation. QG and JYW processed the data. HCS contributed to conception and design the study, participated in data analysis, and approve the final content of the manuscript. All authors discussed the results and commented on the manuscript.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eFunding\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThis study has received funding by the Innovative Medical Device Application Demonstration Program of Shanghai Municipal Commission of Economy and Informatization (grant number: 23SHS01200), the Key Program of Ministry of Industry and Information Technology of China (CEIEC-2022-ZM02-0219), the Chinese National Key Clinical Specialty Program (grant number: YWP2022-007), and the National Key Research and Development Program of China (grant number: 2022YFC2406902).\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eData availability\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe datasets generated during and/or analysed during the current study are available from the corresponding author on reasonable request.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eCode\u003c/strong\u003e \u003cstrong\u003eavailability\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eNot applicable.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eEthics approval and consent to participate\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eInstitutional Review Board approval was obtained from Zhongshan Hospital, Fudan University, and informed consent was obtained from all individual participants included in the study.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eConsent for publication\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe requirement for informed consent was waived.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eCompeting Interests\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eQ.G. and J.W. are the employees of United Imaging Healthcare Co., Ltd., Shanghai, China. The remaining authors declare that they have no relevant financial or non-financial interests to disclose.\u003c/p\u003e"},{"header":"References","content":"\u003col\u003e\n \u003cli\u003eRowe SP, Pomper MG. Molecular imaging in oncology: Current impact and future directions. CA Cancer J Clin. 2022;72(4):333-52.\u003c/li\u003e\n \u003cli\u003eMingels C, Caobelli F, Alavi A, et al. Total-body PET/CT or LAFOV PET/CT? Axial field-of-view clinical classification. Eur J Nucl Med Mol Imaging. 2024;51(4):951-3.\u003c/li\u003e\n \u003cli\u003eSpencer BA, Berg E, Schmall JP, et al. Performance Evaluation of the uEXPLORER Total-Body PET/CT Scanner Based on NEMA NU 2-2018 with Additional Tests to Characterize PET Scanners with a Long Axial Field of View. J Nucl Med. 2021;62(6):861-70.\u003c/li\u003e\n \u003cli\u003ePrenosil GA, Sari H, F\u0026uuml;rstner M, et al. Performance Characteristics of the Biograph Vision Quadra PET/CT System with a Long Axial Field of View Using the NEMA NU 2-2018 Standard. J Nucl Med. 2022;63(3):476-84.\u003c/li\u003e\n \u003cli\u003eKarp JS, Viswanath V, Geagan MJ, et al. PennPET Explorer: Design and Preliminary Performance of a Whole-Body Imager. J Nucl Med. 2020;61(1):136-43.\u003c/li\u003e\n \u003cli\u003eZhang H, Ren C, Liu Y, et al. Performance Characteristics of a New Generation 148-cm Axial Field-of-View uMI Panorama GS PET/CT System with Extended NEMA NU 2-2018 and EARL Standards. J Nucl Med. 2024;jnumed.124.267963.\u003c/li\u003e\n \u003cli\u003eFilippi L, Dimitrakopoulou-Strauss A, Evangelista L, Schillaci O. Long axial field-of-view PET/CT devices: are we ready for the technological revolution? Expert Rev Med Devices. 2022;19(10):739-43.\u003c/li\u003e\n \u003cli\u003eAcuff SN, Osborne D. Clinical Workflow Considerations for Implementation of Continuous-Bed-Motion PET/CT. J Nucl Med Technol. 2016;44(2):55-8.\u003c/li\u003e\n \u003cli\u003eYamashita S, Yamamoto H, Nakaichi T, Yoneyama T, Yokoyama K. Comparison of image quality between step-and-shoot and continuous bed motion techniques in whole-body (18)F-fluorodeoxyglucose positron emission tomography with the same acquisition duration. Ann Nucl Med. 2017;31(9):686-95.\u003c/li\u003e\n \u003cli\u003eMingels C, Chung KJ, Pantel AR, et al. Total-Body PET/CT: Challenges and Opportunities. Semin Nucl Med. 2024;S0001-2998(24)00076-X.\u003c/li\u003e\n \u003cli\u003eGu T, Liu S, Hou X, et al. Low dose optimization for total-body 2-[(18)F]FDG PET/CT imaging: a single-center study on feasibility based on body mass index stratification. Eur Radiol. 2024.\u003c/li\u003e\n \u003cli\u003eYu H, Gu Y, Fan W, et al. Expert consensus on oncological [18F] FDG total-body PET/CT imaging (version 1). European Radiology. 2023;33(1):615-26.\u003c/li\u003e\n \u003cli\u003eHu P, Zhang Y, Yu H, et al. Total-body 18 F-FDG PET/CT scan in oncology patients: how fast could it be? European journal of nuclear medicine and molecular imaging. 2021;48:2384-94.\u003c/li\u003e\n \u003cli\u003eHu Y, Liu G, Yu H, et al. Feasibility of Acquisitions Using Total-Body PET/CT with an Ultra-Low (18)F-FDG Activity. J Nucl Med. 2022;63(6):959-65.\u003c/li\u003e\n \u003cli\u003eVandenberghe S, Moskal P, Karp JS. State of the art in total body PET. EJNMMI Phys. 2020;7(1):35.\u003c/li\u003e\n \u003cli\u003eChen, W, Liu, L, Li, Y. et al. Evaluation of pediatric malignancies using total-body PET/CT with half-dose [18F]-FDG. Eur J Nucl Med Mol Imaging\u003cem\u003e.\u003c/em\u003e 2022;49:4145\u0026ndash;4155.\u0026nbsp;\u003c/li\u003e\n \u003cli\u003eAbdelhafez Y, Raychaudhuri SP, Mazza D, et al. Total-Body 18F-FDG PET/CT in Autoimmune Inflammatory Arthritis at Ultra-Low Dose: Initial Observations.\u003cem\u003e\u0026nbsp;J Nucl Med\u003c/em\u003e. 2022;63:1579-1585.\u0026nbsp;\u003c/li\u003e\n \u003cli\u003eAdili D, Cai D, Wu B, et al. An exploration of the feasibility and clinical value of half-dose 5-h total-body 18F-FDG PET/CT scan in patients with Takayasu arteritis. Eur J Nucl Med Mol Imaging. 2023;50:2375-2385.\u003c/li\u003e\n \u003cli\u003eTan H, Qi C, Cao Y, et al. Ultralow-dose [18F]FDG PET/CT imaging: demonstration of feasibility in dynamic and static images. Eur Radiol.\u003cem\u003e\u0026nbsp;\u003c/em\u003e2023;33:5017-5027.\u0026nbsp;\u003c/li\u003e\n \u003cli\u003eLiu G, Xu H, Hu P, et al. Kinetic metrics of 18F-FDG in normal human organs identified by systematic dynamic total-body positron emission tomography. Eur J Nucl Med Mol Imaging. 2021;48:2363-2372.\u003c/li\u003e\n \u003cli\u003evan Sluis J, Borra R, Tsoumpas C, et al. Extending the clinical capabilities of short- and long-lived positron-emitting radionuclides through high sensitivity PET/CT. Cancer Imaging. 2022;22:69.\u0026nbsp;\u003c/li\u003e\n \u003cli\u003eLiu G, Gu Y, Sollini M, et al. Expert consensus on workflow of PET/CT with long axial field-of-view. Eur J Nucl Med Mol Imaging. 2024.\u003c/li\u003e\n \u003cli\u003eChen WJ, Rae WID, Kench PL, et al. The potential advantages and workflow challenges of long axial field of view PET/CT. J Med Radiat Sc\u003cem\u003ei\u003c/em\u003e. 2023;70:310-318.\u003c/li\u003e\n \u003cli\u003eBoellaard R, Delgado-Bolton R, Oyen WJ, et al. FDG PET/CT: EANM procedure guidelines for tumour imaging: version 2.0. Eur J Nucl Med Mol Imaging. 2015;42:328-354.\u0026nbsp;\u003c/li\u003e\n \u003cli\u003eVali R, Alessio A, Balza R, et al. SNMMI Procedure Standard/EANM Practice Guideline on Pediatric 18F-FDG PET/CT for Oncology 1.0. J Nucl Med. 2021;62:99-110.\u0026nbsp;\u003c/li\u003e\n \u003cli\u003eDorbala S, Di Carli MF, Delbeke D, et al. SNMMI/ASNC/SCCT guideline for cardiac SPECT/CT and PET/CT 1.0. J Nucl Med. 2013;54:1485-1507.\u0026nbsp;\u003c/li\u003e\n \u003cli\u003eGuedj E, Varrone A, Boellaard R, et al. EANM procedure guidelines for brain PET imaging using [18F]FDG, version 3. Eur J Nucl Med Mol Imaging. 2022;49:632-651.\u0026nbsp;\u003c/li\u003e\n \u003cli\u003eThe weight of nations: an estimation of adult human biomass. BMC Public Health\u003cem\u003e.\u003c/em\u003e 2012;12:439.\u003c/li\u003e\n\u003c/ol\u003e"},{"header":"Tables","content":"\u003cp\u003e\u003cstrong\u003eTable 1.\u0026nbsp;\u003c/strong\u003ePET acquisition time (min) with \u003csup\u003e18\u003c/sup\u003eF-FDG TB PET/CT under four injection dose regimens in high-throughput imaging tests.\u003c/p\u003e\n\u003ctable border=\"0\" cellspacing=\"0\" cellpadding=\"0\" width=\"491\"\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd valign=\"bottom\" style=\"width: 119px;\"\u003e\n \u003cp\u003eBMI (kg, m\u003csup\u003e2\u003c/sup\u003e)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 78px;\"\u003e\n \u003cp\u003eFull-dose\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 85px;\"\u003e\n \u003cp\u003eHalf-dose\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 76px;\"\u003e\n \u003cp\u003e1/3-dose\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 135px;\"\u003e\n \u003cp\u003e1/10-dose\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"bottom\" style=\"width: 119px;\"\u003e\n \u003cp\u003e\u0026lt;25\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 78px;\"\u003e\n \u003cp\u003e3\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 85px;\"\u003e\n \u003cp\u003e4\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 76px;\"\u003e\n \u003cp\u003e5\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 135px;\"\u003e\n \u003cp\u003e10\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"bottom\" style=\"width: 119px;\"\u003e\n \u003cp\u003e25\u0026le;, \u0026lt;29\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 78px;\"\u003e\n \u003cp\u003e3\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 85px;\"\u003e\n \u003cp\u003e5\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 76px;\"\u003e\n \u003cp\u003e6\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 135px;\"\u003e\n \u003cp\u003e11\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"bottom\" style=\"width: 119px;\"\u003e\n \u003cp\u003e\u0026ge;29\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 78px;\"\u003e\n \u003cp\u003e3\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 85px;\"\u003e\n \u003cp\u003e7\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 76px;\"\u003e\n \u003cp\u003e8\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 135px;\"\u003e\n \u003cp\u003e12\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n\u003c/table\u003e\n\u003cp\u003eNote:\u0026nbsp;Full-dose means the injection dose was 3.7MBq/kg per patients.\u003cstrong\u003e\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eTable 2.\u003c/strong\u003e Patient throughput and total \u003csup\u003e18\u003c/sup\u003eF-FDG activity consuption within 8 hours under the four injection dose regimens.\u003c/p\u003e\n\u003cdiv align=\"\"\u003e\n \u003ctable border=\"0\" cellspacing=\"0\" cellpadding=\"0\" width=\"652\"\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd valign=\"bottom\" style=\"width: 227px;\"\u003e\n \u003cp\u003e \u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 95px;\"\u003e\n \u003cp\u003eFull-dose\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 87px;\"\u003e\n \u003cp\u003eHalf-dose\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 95px;\"\u003e\n \u003cp\u003e1/3-dose\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 149px;\"\u003e\n \u003cp\u003e1/10-dose\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"bottom\" style=\"width: 227px;\"\u003e\n \u003cp\u003ePatient number\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 95px;\"\u003e\n \u003cp\u003e60\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 87px;\"\u003e\n \u003cp\u003e48\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 95px;\"\u003e\n \u003cp\u003e43\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 149px;\"\u003e\n \u003cp\u003e30\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"bottom\" style=\"width: 227px;\"\u003e\n \u003cp\u003eTotal activity \u0026nbsp;(\u0026times;1000 MBq)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 95px;\"\u003e\n \u003cp\u003e87.2453\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 87px;\"\u003e\n \u003cp\u003e34.6764\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 95px;\"\u003e\n \u003cp\u003e17.9978\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 149px;\"\u003e\n \u003cp\u003e4.2521\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n \u003c/table\u003e\n\u003c/div\u003e\n\u003cp\u003e\u003cstrong\u003e\u0026nbsp;\u003c/strong\u003e\u003cstrong\u003e\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eTable 3.\u003c/strong\u003e Patient throughput and total working time with different total \u003csup\u003e18\u003c/sup\u003eF-FDG activity dose under the four injection dose regimens.\u003c/p\u003e\n\u003ctable border=\"0\" cellspacing=\"0\" cellpadding=\"0\"\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd rowspan=\"2\" valign=\"bottom\"\u003e\n \u003cp\u003eTotal activity (\u0026times;1000\u0026nbsp;MBq)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd colspan=\"2\" valign=\"bottom\"\u003e\n \u003cp\u003eFull-dose\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd colspan=\"2\" valign=\"bottom\"\u003e\n \u003cp\u003eHalf-dose\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd colspan=\"2\" valign=\"bottom\"\u003e\n \u003cp\u003e1/3-dose\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd colspan=\"2\" valign=\"bottom\"\u003e\n \u003cp\u003e1/10-dose\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"bottom\"\u003e\n \u003cp\u003eN\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\"\u003e\n \u003cp\u003eT\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\"\u003e\n \u003cp\u003eN\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\"\u003e\n \u003cp\u003eT\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\"\u003e\n \u003cp\u003eN\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\"\u003e\n \u003cp\u003eT\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\"\u003e\n \u003cp\u003eN\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\"\u003e\n \u003cp\u003eT\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"bottom\"\u003e\n \u003cp\u003e37\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\"\u003e\n \u003cp\u003e44\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\"\u003e\n \u003cp\u003e5.87\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\"\u003e\n \u003cp\u003e48\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\"\u003e\n \u003cp\u003e8.00\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\"\u003e\n \u003cp\u003e52\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\"\u003e\n \u003cp\u003e9.53\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\"\u003e\n \u003cp\u003e50\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\"\u003e\n \u003cp\u003e13.33\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"bottom\"\u003e\n \u003cp\u003e74\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\"\u003e\n \u003cp\u003e56\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\"\u003e\n \u003cp\u003e7.47\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\"\u003e\n \u003cp\u003e59\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\"\u003e\n \u003cp\u003e9.83\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\"\u003e\n \u003cp\u003e62\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\"\u003e\n \u003cp\u003e11.37\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\"\u003e\n \u003cp\u003e57\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\"\u003e\n \u003cp\u003e15.20\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"bottom\"\u003e\n \u003cp\u003e111\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\"\u003e\n \u003cp\u003e64\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\"\u003e\n \u003cp\u003e8.53\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\"\u003e\n \u003cp\u003e65\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\"\u003e\n \u003cp\u003e10.83\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\"\u003e\n \u003cp\u003e68\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\"\u003e\n \u003cp\u003e12.47\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\"\u003e\n \u003cp\u003e61\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\"\u003e\n \u003cp\u003e16.27\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"bottom\"\u003e\n \u003cp\u003e148\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\"\u003e\n \u003cp\u003e70\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\"\u003e\n \u003cp\u003e9.33\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\"\u003e\n \u003cp\u003e70\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\"\u003e\n \u003cp\u003e11.67\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\"\u003e\n \u003cp\u003e72\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\"\u003e\n \u003cp\u003e13.20\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\"\u003e\n \u003cp\u003e64\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\"\u003e\n \u003cp\u003e17.07\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n\u003c/table\u003e\n\u003cp\u003eNote: N, number of patient; T, total working time in hour\u003cstrong\u003e\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eTable 4\u003c/strong\u003e\u003cstrong\u003e.\u003c/strong\u003e Minimal total \u003csup\u003e18\u003c/sup\u003eF-FDG activity consumotion and combination of dose regimens for 50 patients in unlimited working time or a fixed working time of 8 hours.\u003c/p\u003e\n\u003ctable border=\"0\" cellspacing=\"0\" cellpadding=\"0\"\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd colspan=\"2\"\u003e\n \u003cp\u003eTotal working time\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd rowspan=\"2\"\u003e\n \u003cp\u003eMinimal activity\u0026nbsp;\u003c/p\u003e\n \u003cp\u003e(\u0026times;1000 MBq)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd colspan=\"4\"\u003e\n \u003cp\u003eCombination of 50 patients\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003eType\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003ehour\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003eFull-dose\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003eHalf-dose\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e1/3-dose\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e1/10-dose\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd rowspan=\"11\"\u003e\n \u003cp\u003eUnlimited time\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\"\u003e\n \u003cp\u003e7.63\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\"\u003e\n \u003cp\u003e35.0279\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\"\u003e\n \u003cp\u003e21\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\"\u003e\n \u003cp\u003e29\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\"\u003e\n \u003cp\u003e-\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\"\u003e\n \u003cp\u003e-\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"bottom\"\u003e\n \u003cp\u003e8.32\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\"\u003e\n \u003cp\u003e26.1220\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\"\u003e\n \u003cp\u003e17\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\"\u003e\n \u003cp\u003e-\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\"\u003e\n \u003cp\u003e33\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\"\u003e\n \u003cp\u003e-\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"bottom\"\u003e\n \u003cp\u003e10.53\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\"\u003e\n \u003cp\u003e19.4102\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\"\u003e\n \u003cp\u003e21\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\"\u003e\n \u003cp\u003e-\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\"\u003e\n \u003cp\u003e-\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\"\u003e\n \u003cp\u003e29\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"bottom\"\u003e\n \u003cp\u003e8.85\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\"\u003e\n \u003cp\u003e28.2606\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\"\u003e\n \u003cp\u003e-\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\"\u003e\n \u003cp\u003e19\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\"\u003e\n \u003cp\u003e31\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\"\u003e\n \u003cp\u003e-\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"bottom\"\u003e\n \u003cp\u003e10.83\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\"\u003e\n \u003cp\u003e18.7960\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\"\u003e\n \u003cp\u003e-\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\"\u003e\n \u003cp\u003e25\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\"\u003e\n \u003cp\u003e-\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\"\u003e\n \u003cp\u003e25\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"bottom\"\u003e\n \u003cp\u003e10.83\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\"\u003e\n \u003cp\u003e18.0671\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\"\u003e\n \u003cp\u003e-\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\"\u003e\n \u003cp\u003e-\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\"\u003e\n \u003cp\u003e30\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\"\u003e\n \u003cp\u003e20\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"bottom\"\u003e\n \u003cp\u003e8.32\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\"\u003e\n \u003cp\u003e26.0961\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\"\u003e\n \u003cp\u003e16\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\"\u003e\n \u003cp\u003e3\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\"\u003e\n \u003cp\u003e31\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\"\u003e\n \u003cp\u003e-\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"bottom\"\u003e\n \u003cp\u003e10.50\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\"\u003e\n \u003cp\u003e18.1152\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\"\u003e\n \u003cp\u003e10\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\"\u003e\n \u003cp\u003e15\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\"\u003e\n \u003cp\u003e-\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\"\u003e\n \u003cp\u003e25\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"bottom\"\u003e\n \u003cp\u003e10.33\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\"\u003e\n \u003cp\u003e17.0681\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\"\u003e\n \u003cp\u003e10\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\"\u003e\n \u003cp\u003e-\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\"\u003e\n \u003cp\u003e20\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\"\u003e\n \u003cp\u003e20\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"bottom\"\u003e\n \u003cp\u003e10.63\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\"\u003e\n \u003cp\u003e17.5898\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\"\u003e\n \u003cp\u003e-\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\"\u003e\n \u003cp\u003e12\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\"\u003e\n \u003cp\u003e18\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\"\u003e\n \u003cp\u003e20\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"bottom\"\u003e\n \u003cp\u003e10.33\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\"\u003e\n \u003cp\u003e17.0496\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\"\u003e\n \u003cp\u003e9\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\"\u003e\n \u003cp\u003e3\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\"\u003e\n \u003cp\u003e18\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\"\u003e\n \u003cp\u003e20\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd rowspan=\"7\"\u003e\n \u003cp\u003ewithin 8 hours\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\"\u003e\n \u003cp\u003e7.63\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\"\u003e\n \u003cp\u003e35.0279\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\"\u003e\n \u003cp\u003e21\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\"\u003e\n \u003cp\u003e29\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\"\u003e\n \u003cp\u003e-\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\"\u003e\n \u003cp\u003e-\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"bottom\"\u003e\n \u003cp\u003e7.97\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\"\u003e\n \u003cp\u003e26.8250\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\"\u003e\n \u003cp\u003e24\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\"\u003e\n \u003cp\u003e-\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\"\u003e\n \u003cp\u003e26\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\"\u003e\n \u003cp\u003e-\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"bottom\"\u003e\n \u003cp\u003e8.00\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\"\u003e\n \u003cp\u003e31.8385\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\"\u003e\n \u003cp\u003e40\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\"\u003e\n \u003cp\u003e-\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\"\u003e\n \u003cp\u003e-\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\"\u003e\n \u003cp\u003e10\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"bottom\"\u003e\n \u003cp\u003e8.00\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\"\u003e\n \u003cp\u003e26.6548\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\"\u003e\n \u003cp\u003e22\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\"\u003e\n \u003cp\u003e4\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\"\u003e\n \u003cp\u003e24\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\"\u003e\n \u003cp\u003e-\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"bottom\"\u003e\n \u003cp\u003e8.00\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\"\u003e\n \u003cp\u003e28.4863\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\"\u003e\n \u003cp\u003e28\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\"\u003e\n \u003cp\u003e16\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\"\u003e\n \u003cp\u003e-\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\"\u003e\n \u003cp\u003e6\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"bottom\"\u003e\n \u003cp\u003e7.98\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\"\u003e\n \u003cp\u003e26.0702\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\"\u003e\n \u003cp\u003e27\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\"\u003e\n \u003cp\u003e-\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\"\u003e\n \u003cp\u003e21\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\"\u003e\n \u003cp\u003e2\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"bottom\"\u003e\n \u003cp\u003e8.00\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\"\u003e\n \u003cp\u003e25.8741\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\"\u003e\n \u003cp\u003e27\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\"\u003e\n \u003cp\u003e4\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\"\u003e\n \u003cp\u003e16\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\"\u003e\n \u003cp\u003e3\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n\u003c/table\u003e\n\u003cp\u003e\u003cbr\u003e\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eTable 5.\u0026nbsp;\u003c/strong\u003eComparison between the theoretical estimation and actual clinical validation results of patient throughput within 8 hours and the average time spent in the scanning room per patients under the four injection dose regimens.\u003c/p\u003e\n\u003cdiv align=\"\"\u003e\n \u003ctable border=\"0\" cellspacing=\"0\" cellpadding=\"0\" width=\"739\"\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd rowspan=\"2\" valign=\"bottom\" style=\"width: 192px;\"\u003e\u003cbr\u003e\u003c/td\u003e\n \u003ctd colspan=\"2\" valign=\"bottom\" style=\"width: 144px;\"\u003e\n \u003cp\u003eFull dose\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd colspan=\"2\" valign=\"bottom\" style=\"width: 134px;\"\u003e\n \u003cp\u003eHalf dose\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd colspan=\"2\" valign=\"bottom\" style=\"width: 134px;\"\u003e\n \u003cp\u003e1/3 dose\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd colspan=\"4\" valign=\"bottom\" style=\"width: 134px;\"\u003e\n \u003cp\u003e1/10 dose\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"bottom\" style=\"width: 48px;\"\u003e\n \u003cp\u003eT\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 96px;\"\u003e\n \u003cp\u003eAc\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 47px;\"\u003e\n \u003cp\u003eT\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 88px;\"\u003e\n \u003cp\u003eAc\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 48px;\"\u003e\n \u003cp\u003eT\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 86px;\"\u003e\n \u003cp\u003eAc\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd colspan=\"2\" valign=\"bottom\" style=\"width: 47px;\"\u003e\n \u003cp\u003eT\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd colspan=\"2\" valign=\"bottom\" style=\"width: 88px;\"\u003e\n \u003cp\u003eAc\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"bottom\" style=\"width: 192px;\"\u003e\n \u003cp\u003eAge, years (Mean \u0026plusmn; SD)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 48px;\"\u003e\n \u003cp\u003e-\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 96px;\"\u003e\n \u003cp\u003e59.9 \u0026plusmn; 14.7\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 47px;\"\u003e\n \u003cp\u003e-\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 88px;\"\u003e\n \u003cp\u003e62.0 \u0026plusmn; 11.4\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 48px;\"\u003e\n \u003cp\u003e-\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 86px;\"\u003e\n \u003cp\u003e61.6 \u0026plusmn; 12.3\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd colspan=\"2\" style=\"width: 47px;\"\u003e\n \u003cp\u003e-\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd colspan=\"2\" style=\"width: 88px;\"\u003e\n \u003cp\u003e64.0 \u0026plusmn; 9.5\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"bottom\" style=\"width: 192px;\"\u003e\n \u003cp\u003eFemale (counts (percents))\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 48px;\"\u003e\n \u003cp\u003e-\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 96px;\"\u003e\n \u003cp\u003e24 (40.0%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 47px;\"\u003e\n \u003cp\u003e-\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 88px;\"\u003e\n \u003cp\u003e17 (34.7%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 48px;\"\u003e\n \u003cp\u003e-\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 86px;\"\u003e\n \u003cp\u003e18 (37.5%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd colspan=\"2\" style=\"width: 47px;\"\u003e\n \u003cp\u003e-\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd colspan=\"2\" style=\"width: 88px;\"\u003e\n \u003cp\u003e12 (42.9%)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"bottom\" style=\"width: 192px;\"\u003e\n \u003cp\u003eWeight, kg\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 48px;\"\u003e\n \u003cp\u003e-\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 96px;\"\u003e\n \u003cp\u003e63.1 \u0026plusmn; 11.3\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 47px;\"\u003e\n \u003cp\u003e-\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 88px;\"\u003e\n \u003cp\u003e66.0 \u0026plusmn; 10.8\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 48px;\"\u003e\n \u003cp\u003e-\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 86px;\"\u003e\n \u003cp\u003e65.7 \u0026plusmn; 14.1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd colspan=\"2\" style=\"width: 47px;\"\u003e\n \u003cp\u003e-\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd colspan=\"2\" style=\"width: 88px;\"\u003e\n \u003cp\u003e60.9\u0026plusmn; 9.2\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"bottom\" style=\"width: 192px;\"\u003e\n \u003cp\u003eBMI (Mean \u0026plusmn; SD)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 48px;\"\u003e\n \u003cp\u003e-\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 96px;\"\u003e\n \u003cp\u003e23.0 \u0026plusmn; 3.4\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 47px;\"\u003e\n \u003cp\u003e-\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 88px;\"\u003e\n \u003cp\u003e23.8 \u0026plusmn; 3.1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 48px;\"\u003e\n \u003cp\u003e-\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 86px;\"\u003e\n \u003cp\u003e23.8 \u0026plusmn; 3.9\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd colspan=\"2\" style=\"width: 47px;\"\u003e\n \u003cp\u003e-\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd colspan=\"2\" style=\"width: 88px;\"\u003e\n \u003cp\u003e22.6 \u0026plusmn; 3.0\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"bottom\" style=\"width: 192px;\"\u003e\n \u003cp\u003ePET acquisition time, minutes\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 48px;\"\u003e\n \u003cp\u003e3.00\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 96px;\"\u003e\n \u003cp\u003e3.00\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 47px;\"\u003e\n \u003cp\u003e5.00\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 88px;\"\u003e\n \u003cp\u003e4.51\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 48px;\"\u003e\n \u003cp\u003e6.00\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 86px;\"\u003e\n \u003cp\u003e5.55\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd colspan=\"2\" style=\"width: 47px;\"\u003e\n \u003cp\u003e11.00\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd colspan=\"2\" style=\"width: 88px;\"\u003e\n \u003cp\u003e10.20\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"bottom\" style=\"width: 192px;\"\u003e\n \u003cp\u003eCT acquisition time, minutes\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 48px;\"\u003e\n \u003cp\u003e1.00\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 96px;\"\u003e\n \u003cp\u003e1.13\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 47px;\"\u003e\n \u003cp\u003e1.00\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 88px;\"\u003e\n \u003cp\u003e1.11\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 48px;\"\u003e\n \u003cp\u003e1.00\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 86px;\"\u003e\n \u003cp\u003e1.14\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd colspan=\"2\" style=\"width: 47px;\"\u003e\n \u003cp\u003e1.00\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd colspan=\"2\" style=\"width: 88px;\"\u003e\n \u003cp\u003e1.13\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"bottom\" style=\"width: 192px;\"\u003e\n \u003cp\u003ePatient preparation time, minutes\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 48px;\"\u003e\n \u003cp\u003e4.00\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 96px;\"\u003e\n \u003cp\u003e3.63\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 47px;\"\u003e\n \u003cp\u003e4.00\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 88px;\"\u003e\n \u003cp\u003e4.37\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 48px;\"\u003e\n \u003cp\u003e4.00\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 86px;\"\u003e\n \u003cp\u003e2.50\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd colspan=\"2\" style=\"width: 47px;\"\u003e\n \u003cp\u003e4.00\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd colspan=\"2\" style=\"width: 88px;\"\u003e\n \u003cp\u003e4.21\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"bottom\" style=\"width: 192px;\"\u003e\n \u003cp\u003eTotal time in the scanning room, minutes\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 48px;\"\u003e\n \u003cp\u003e8.00\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 96px;\"\u003e\n \u003cp\u003e8.00\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 47px;\"\u003e\n \u003cp\u003e10.00\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 88px;\"\u003e\n \u003cp\u003e9.79\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 48px;\"\u003e\n \u003cp\u003e11.00\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 86px;\"\u003e\n \u003cp\u003e10.00\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd colspan=\"2\" style=\"width: 47px;\"\u003e\n \u003cp\u003e16.00\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd colspan=\"2\" style=\"width: 88px;\"\u003e\n \u003cp\u003e17.14\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"bottom\" style=\"width: 192px;\"\u003e\n \u003cp\u003ePatient number\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 48px;\"\u003e\n \u003cp\u003e60\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 96px;\"\u003e\n \u003cp\u003e60\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 47px;\"\u003e\n \u003cp\u003e48\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 88px;\"\u003e\n \u003cp\u003e49\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 48px;\"\u003e\n \u003cp\u003e43\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd colspan=\"2\" style=\"width: 124px;\"\u003e\n \u003cp\u003e48\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd colspan=\"2\" style=\"width: 32px;\"\u003e\n \u003cp\u003e30\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 65px;\"\u003e\n \u003cp\u003e28\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n \u003c/table\u003e\n\u003c/div\u003e\n\u003cp\u003eNote: T, theoretical value; Ac, actual value\u0026nbsp;\u003c/p\u003e"}],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":true,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":false,"hideJournal":false,"highlight":"","institution":"","isAcceptedByJournal":true,"isAuthorSuppliedPdf":false,"isDeskRejected":"","isHiddenFromSearch":false,"isInQc":false,"isInWorkflow":true,"isPdf":false,"isPdfUpToDate":true,"isWithdrawnOrRetracted":false,"journal":{"display":true,"email":"[email protected]","identity":"ejnmmi-research","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"ejre","sideBox":"Learn more about [EJNMMI Research](http://ejnmmires.springeropen.com/)","snPcode":"","submissionUrl":"https://www.editorialmanager.com/ejre/default.aspx","title":"EJNMMI Research","twitterHandle":"@officialEANM","acdcEnabled":true,"dfaEnabled":true,"editorialSystem":"em","reportingPortfolio":"BMC/SO AJ","inReviewEnabled":true,"inReviewRevisionsEnabled":true},"keywords":"Total-body PET/CT, Scan strategy, Scanning efficiency, 18F-FDG, Throughput","lastPublishedDoi":"10.21203/rs.3.rs-6140160/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-6140160/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003cp\u003e\u003cstrong\u003eBackground \u003c/strong\u003eThe study aims to maximize clinical scan efficiency for Total-body (TB) \u003csup\u003e18\u003c/sup\u003eF-FDG PET/CT systems by optimizing scan strategies based on theoretical models and clinical experience from a single center.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eResults \u003c/strong\u003eThis prospective study include two parts. The first part involved simulation experiments using theoretical models to maximize patient throughput and/or minimizing radiotracer activity across four clinical scanning scenarios: fixed working time, predetermined radiotracer activity, integration of various injection dose regimens for a fixed number of patients, and incorporation of dynamic scans into routine static scans within a fixed working time. The optimal scan strategies for these scenarios were then proposed. The second part validated the estimated throughput results through high-throughput tests performed in the real clinical settings with an fixed working time of 8 hours. Under a fixed working time of 8 hours, the theoretical patient throughput for full-dose, half-dose, 1/3-dose, and 1/10-dose injection regimens was 60, 48, 43, 30 patients, respectively. The corresponding real clinical throughput achieved was 60, 49, 48, 28 patients. For a total \u003csup\u003e18\u003c/sup\u003eF-FDG activity of 37,000 to 148,000 MBq (1 to 4 Ci), the 1/3 dose injection regimen yielded the highest patient throughput, ranging 52 to 72 patients. Strategically combining various injection dose regimens could reduce radiotracer activity consumption. Additionally, placing full-dose dynamic scans after routine static scans for full-dose, half-dose, and 1/3 dose, and before 1/10 dose, proved to ba more economical strategies.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eConclusions \u003c/strong\u003eOptimized scan strategies for typical clinical scenarios of TB \u003csup\u003e18\u003c/sup\u003eF-FDG PET/CT systems were proposed, which could promote clinical scan efficiency and accommodate diverse clinical requirements.\u003c/p\u003e","manuscriptTitle":"Total-Body 18F-FDG PET/CT: More Choices to Promote Clinical Scanning Efficiency","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2025-04-03 06:31:29","doi":"10.21203/rs.3.rs-6140160/v1","editorialEvents":[{"type":"communityComments","content":0},{"type":"decision","content":"Minor Revision","date":"2025-05-23T03:19:28+00:00","index":"","fulltext":""},{"type":"reviewerAgreed","content":"","date":"2025-03-31T12:30:35+00:00","index":0,"fulltext":""},{"type":"reviewersInvited","content":"","date":"2025-03-28T07:44:38+00:00","index":"","fulltext":""},{"type":"editorAssigned","content":"","date":"2025-03-10T13:19:33+00:00","index":"","fulltext":""},{"type":"submitted","content":"EJNMMI Research","date":"2025-03-06T09:02:33+00:00","index":"","fulltext":""}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"ejnmmi-research","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"ejre","sideBox":"Learn more about [EJNMMI Research](http://ejnmmires.springeropen.com/)","snPcode":"","submissionUrl":"https://www.editorialmanager.com/ejre/default.aspx","title":"EJNMMI Research","twitterHandle":"@officialEANM","acdcEnabled":true,"dfaEnabled":true,"editorialSystem":"em","reportingPortfolio":"BMC/SO AJ","inReviewEnabled":true,"inReviewRevisionsEnabled":true}}],"origin":"","ownerIdentity":"9c97a548-23eb-4c24-a907-c2454a75fc3a","owner":[],"postedDate":"April 3rd, 2025","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"published-in-journal","subjectAreas":[],"tags":[],"updatedAt":"2025-08-04T16:42:10+00:00","versionOfRecord":{"articleIdentity":"rs-6140160","link":"https://doi.org/10.1186/s13550-025-01290-y","journal":{"identity":"ejnmmi-research","isVorOnly":false,"title":"EJNMMI Research"},"publishedOn":"2025-08-02 16:05:28","publishedOnDateReadable":"August 2nd, 2025"},"versionCreatedAt":"2025-04-03 06:31:29","video":"","vorDoi":"10.1186/s13550-025-01290-y","vorDoiUrl":"https://doi.org/10.1186/s13550-025-01290-y","workflowStages":[]},"version":"v1","identity":"rs-6140160","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-6140160","identity":"rs-6140160","version":["v1"]},"buildId":"8U1c8b4HqxoKbykW_rLl7","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}