Achieving NPVR ≥ 80% as Technical Success of High-Intensity Focused Ultrasound Ablation for Uterine Fibroids: a cohort study

Achieving NPVR ≥ 80% as Technical Success of High-Intensity Focused Ultrasound Ablation for Uterine Fibroids: a cohort study | 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 Achieving NPVR ≥ 80% as Technical Success of High-Intensity Focused Ultrasound Ablation for Uterine Fibroids: a cohort study Shuang Li, Meijie Yang, Jingwen Yu, Wangwa Ma, Yongbin Deng, Liang Hu, and 1 more This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-3817348/v1 This work is licensed under a CC BY 4.0 License Status: Under Review Version 1 posted 8 You are reading this latest preprint version Abstract Objective: To report the long-term re-intervention of patients with uterine fibroids after ultrasound-guided high-intensity focused ultrasound (USgHIFU) ablation, and analyse the influencing factors of re-intervention in group of NPVR ≥80%. Materials and Methods: The patients were divided into four groups according to different non-perfusion volume ratio (NPVR). Kaplan-Meier survival curve was used to analyse the long-term re-intervention in different NPVR groups, and Cox regression was used to analyse the influencing factors of re-intervention in the NPVR ≥ 80% group. Main Results: Patients with single uterine fibroid who underwent USgHIFU from January 2012 to December 2019 in our hospital were enrolled. A total of 1,257 patients were enrolled, of which 920 were successfully followed up. The median follow-up time was 88 months, and the median NPVR was 85.2%. The cumulative re-intervention rates of 1, 3, 5, 8 and 10 years after USgHIFU were 3.4%, 11.8%, 16.8%, 22.6% and 24.1%, respectively. The 10-year cumulative re-intervention rate was 37.3% in the group of NPVR <70%, 31.0% in the group of NPVR 70%–79%, 18.2% in the group of NPVR 80%–89% and 17.8% in the group of NPVR ≥90% ( P <0.05). However, no difference was found between the group of NPVR 80%−89% and the group of NPVR ≥90% ( P =0.499). Age of patients and signal intensity on T 2 WI of tumours were independent risk factors for long-term re-intervention when NPVR was ≥80%. Lower age and higher signal intensity on T 2 WI corresponded to a higher risk of re-intervention occurrence. Conclusion: USgHIFU, as an alternative treatment of uterine fibroids, has a reliable long-term efficiency. NPVR ≥80% can reduce the long-term re-intervention rates of patients, which can be used as a sign of technical success. However, an important step is to assess before ablation, considering both age of patients and fibroids of signal intensity on T 2 WI. Trial registration: This retrospective study was approved by the ethics committee at our institution (Registration No. HF2023001; Date: 06/04/2023). The Chinese Clinical Trial Registry provided full approval for the study protocol (Registration No. CHiCTR2300074797; Date: 16/08/2023). high intensity focused ultrasound (HIFU) uterine fibroids non-perfusion volume ratio (NPVR) ablation re-intervention Figures Figure 1 Figure 2 Figure 3 Background Uterine fibroid, also known as leiomyoma, is the most common benign reproductive system tumours in females of childbearing age. The incidence rate of uterine fibroids ranges from 4.5–68.6% due to population characteristics such as race, region, health status, etc.( 1 ) About 25% of women with uterine fibroids have clinical symptoms( 2 , 3 ), such as menorrhagia, irregular bleeding, pelvic pain, or infertility( 4 – 6 ), which seriously affect women’s quality of life. Treatment options for uterine fibroids require individualised clinical management that considers both symptom relief and the patient’s desire to be pregnant. High-intensity focused ultrasound (HIFU) ablation could cause instant coagulative necrosis (1–3 seconds) in a well-circumscribed area of 1.5 × 1.5 × 10 mm through focusing the ultrasound beam on the tumor, including ultrasound-guided high-intensity focused ultrasound (USgHIFU) ablation and magnetic resonance-guided high-intensity focused ultrasound (MRgHIFU) ablation ( 7 ). As a completely non-invasive treatment technology at present, it only damages the target area, thus being effective, safe and controllable ( 8 ). The non-perfusion volume (NPV) is the volume of area without perfusion on post-operative contrast-enhanced MRI within 3 days which was used to evaluate the therapeutic effectiveness. The non-perfusion volume ratio (NPVR), a predictor of re-intervention in the short to medium term, is defined as the proportion of non-perfusion volume to preoperative fibroid volume ( 9 , 10 ). Previous studies showed that the two-year clinical efficiency of USgHIFU was similar to that of myomectomy when NPVR is up to 70% ( 11 ). However, clinical evidence of the long-term efficacy of uterine fibroids after USgHIFU is still lacking. Therefore, the long-term efficacy of USgHIFU and re-intervention rates in different NPVR were explore. Furthermore, the influencing factors of long-term re-intervention in patients with NPVR ≥ 80% were analysed to provide a basis for an appropriate therapeutic regimen and case screening. Methods Patients Patients with uterine fibroids who underwent USgHIFU in the Minimally Invasive and Noninvasive Treatment Centre of our hospital from January 2012 to December 2019 were enrolled. The inclusion criteria were as follows: ( 1 ) premenopausal women between 18–50 years old; ( 2 ) patients diagnosed with International Federation of Obstetrics and Gynecology Federation International of Gynecology and Obstetrics (FIGO) types 1–6 uterine fibroids by magnetic resonance imaging (MRI); ( 3 ) the diameter of fibroid was at least 2 cm; ( 4 ) patients received fibroid-related treatment for the first time. The exclusion criteria were as follows: ( 1 ) patients with a special type of fibroids, such as FIGO type 0, 7 or 8; ( 2 ) patients with other gynaecological diseases, such as adenomyosis and ovarian tumour; ( 3 ) patients with serious organic lesions, such as heart failure, liver cirrhosis, etc.; ( 4 ) patients diagnosed with or suspected to have a malignant disease, such as sarcoma of uterus; ( 5 ) patients unwilling to undergo follow-up. USgHIFU ablation One-session USgHIFU ablation was performed by physicians with at least 3 years of HIFU clinical experience. A focused ultrasound tumour therapeutic system (Model-JC, Chongqing Haifu Medical Technology Co., Ltd., Chongqing, China) was used. The ultrasound transducer worked with a frequency of 0.5–1.5 MHz, and energy was adjusted within a range of 350–400 W. The guided ultrasound frequency used for real-time monitoring was 3.5 MHz (Esaote, MyLab70, Italy). All patients received diet preparation, enema cleansing and skin preparation (shaving, degreasing and degassing) before treatment. Fentanyl (0.8–1 ug/kg) and midazolam hydrochloride (0.02–0.03 mg/kg) were administered to maintain conscious sedation while reducing patient discomfort. The patients were prone on the HIFU table with their anterior abdominal wall in contact with degassed water. An adjustable water balloon was placed between the abdominal wall and transducer when it was necessary in case the bowel blocked the acoustic pathway. The treatment focuses were at least 15 mm from the endometrium and 10 mm from the perimetrium. The ultrasonic sonication time and acoustic power were adjusted based on the change in patient tolerance and the target area. Greyscale changes in real-time ultrasonographic imaging served as the ablation marker. The sonication was terminated when the increased greyscale covered the planned ablation area, and sonication time was controlled within 3000s. The patients were instructed to remain in the prone position for 2 hours after procedure. MRI evaluation and classification All patients received an MRI scan 1 week before and within 3 days after the treatment. T 1 WI, T 2 WI and enhanced T 1 WI was performed with a 3.0-T MRI system (Singa HD Excite, GE Healthcare, USA). The MR images were analyzed by a radiologist who had completed 5 years of specialization in abdominal MR imaging (Reader 1) and they were validated by another radiologist (Reader 2) who had 15 years of experience in abdominal MR imaging; in case of disagreement, Reader 2 retraced the image and this was considered as the final decision. The MR images were evaluated and measured as follows: ( 1 ) Type of fibroid: types 1–6. The fibroids were categorised according to the FIGO ( 12 ). ( 2 ) Location of fibroids: anterior or posterior. The fibroid that the acoustic pathway did not pass through the uterine cavity during USgHIFU ablation was an anterior fibroid. Otherwise, it was a posterior fibroid. ( 3 ) Signal intensity on T 2 WI: hypointense, isointense or hyperintense. ( 4 ) Enhancement type on T 1 WI: mild, moderate or significant. The degree of enhancement was compared with normal myometrium according to the dynamic contrast-enhanced MR image within 60 s of contrast medium injection. ( 5 ) Maximum diameter of fibroids: Three dimensions were measured on T 2 WI before the treatment: longitudinal diameter (D 1 ), anteroposterior diameter (D 2 ) and transverse diameter (D 3 ). The maximum of the three dimensions was selected as the maximum diameter of fibroids. ( 6 ) Calculation of fibroid volumes and NPVR: The volume was calculated by using the following equation: V = 0.5233 × D 1 × D 2 × D 3 . ( 7 ) Calculation of NPVR: NPV was evaluated according to the formula above on enhanced T 1 WI after the treatment. NPVR was defined as NPV / post-treatment fibroid volume × 100%. Follow-up A gynecologist who had worked for more than 3-year experience followed up visit to the patients by telephone according to the follow-up content and criteria set by our research team. If the patients had undergone re-intervention, the method, as well as the reason and time, needed to be recorded. Surgical treatment due to uterine fibroids was defined as re-intervention, such as myomectomy, USgHIFU, hysterectomy and UAE. Patients who were diagnosed with adenomyosis or malignant disease were also followed up. The follow-up end point is set by re-intervention for fibroids and hysterectomy for other reasons. If patients were unable to be contacted multiple times within 3 days, they were confirmed as lost to follow-up. Statistical analysis SPSS version 26.0 (IBM, Armonk, NY, USA) was used for statistical analysis. Normally distributed data were reported as mean ± standard deviation (SD), and non-normally distributed data were reported as medians and interquartile range. Categorical data were expressed as numerals and percentages (%). Comparisons among groups were conducted using multiple-factor analysis of variance, Mann-Whitney U test, Kruskal-Wallis test, chi-square test, continuous correction test and Fisher’s exact test, with a P value less than 0.05 considered as significant. Kaplan-Meier survival curve was used to explore cumulative re-intervention rates, and Cox regression was used to analyse the influencing factors. Results Baseline characteristics of patients and Long-term efficacy of USgHIFU A total of 1,257 patients were enrolled, of which 920 patients were successfully followed up while 337 patients (26.8%) were lost. The patients’ median age was 39.0 years (IQR 33.0, 43.0), and median BMI was 22.0 kg/m 2 (IQR 20.4, 23.8). The maximum diameter of uterine fibroids was 56.0 mm (47.0, 68.0), and the volume of fibroids was 71.0 cm 3 (42.0, 122.4). Other baseline characteristics are given in Table 1 . Table 1 Baseline characteristics of patients and cumulative re-intervention rates Variable Total patients (n = 1257) Patients of NPVR ≥ 80% (n = 793) Number of successful follow-up cases (n) 920 581 General patient data Age (years) * 39.0 (33.0, 43.0) 39.0 (33.0, 43.0) BMI (kg/m 2 ) 22.0 (20.4, 23.8) 22.0 (20.3, 23.7) Family history of fibroids (yes/no) (n) 82/1175 58/735 History of smoking or drinking (yes/no) (n) 76/1181 49/744 History of lower abdominal surgery (yes/no) (n) 427/830 258/525 History of childbirth (yes/no) (n) 920/337 582/211 Fibroid data of MR imaging Type (Ⅰ-Ⅱ/Ⅲ-Ⅳ/Ⅴ-Ⅵ) (n) 143/236/878 92/148/553 Location (anterior/posterior) ( n ) 860/397 567/226 Signal intensity on T 2 WI (hypointense/isointense/hyperintense) (n) 407/355/495 303/235/255 Enhancement type on T 1 WI of fibroids (mild / moderate / significant) (n) 417/560/280 297/347/149 Maximum diameter (mm) 56.0 (47.0, 68.0) 56.0 (47.0, 67.0) Volume (cm 3 ) 71.0 (42.0, 122.4) 71.3 (42.3, 120.7) Cumulative re-intervention rate (%) 1 years 3.4 1.3 3 years 11.8 7.4 5 years 16.8 11.6 8 years 22.6 16.5 10 years 24.1 17.8 Note: Data are median value; interquartile range in brackets. The median power of USgHIFU ablation was 400.0 W (IQR 399.8 W, 400 W), the median sonication time was 880.0 seconds (IQR 521.0 seconds, 1403.8 seconds), the median dose was 342.8 KJ (IQR 200.0 KJ, 550.0 KJ) and the median NPVR was 85.2% (IQR 71.6%, 93.8%). No SIR C-F complications such as skin burn and intestinal injury etc., and no long-term complications related to USgHIFU occurred during and after treatment. The median follow-up time after USgHIFU was 88 months (IQR 67, 110), ranging from 45 to 129 months. The cumulative re-intervention rates 1, 3, 5, 8, and 10 years after USgHIFU were 3.4%, 11.8%, 16.8%, 22.6% and 24.1% as indicated by survival analysis (Table 1 ). The main reason for re-intervention was re-enlargement of original fibroids (48.8%, 124/254), followed by symptom recurrence (15.7%, 40/254); removing fibroids during other surgeries such as caesarean section (9.8%, 25/254); new fibroids 9.8%, 25/254); poor ablation (5.9%, 15/254); psychological factors due to the follow-up image of ablated residual fibroid, which was asymptomatic and did not grow (4.3%, 11/254); pre-fertility preparation (3.9%, 10/254); and hysteroscopic surgery because of submucosal fibroids expelled (1.6%, 4/254) (Fig. 1 ). Re-intervention methods included myomectomy (68.5%, 174/254), USgHIFU (17.7%, 45/254), hysterectomy (13.4%, 34/254) and UAE (0.4%, 1/382). In addition, six patients (0.7%) were diagnosed with adenomyosis after USgHIFU. Eight patients were diagnosed with thyroid cancer, and three patients were diagnosed with breast cancer when we followed up. Cumulative re-intervention in different NPVR groups The patients were divided into four groups according to different NPVR: <70% (275/1275), 70–79% (189/1275), 80–89% (283/1275) and 90–100% (510/1275) (Fig. 2 ). The sonication time and dose of NPVR 90%-100% group were significant lower than those of other groups ( P < 0.001) (Table 2 ). The Kaplan-Meier survival curve indicated that the group of NPVR 90–100% had the lowest re-intervention rate (17.9%), followed by the group of NPVR 80–89% (18.3%), the group of NPVR 70–79% (31.1%), and the group of NPVR < 70%, which had the highest re-intervention rate (37.4%), with significant differences ( P < 0.001). However, a comparison between the group of NPVR 80–89% and the group of NPVR 90–100% showed no significant differences in long-term re-intervention rates ( P = 0.499) (Fig. 3 ). Table 2 The ablation results of USgHIFU in different NPVR Variable NPVR < 70% (n = 275) NPVR 70–79% (n = 189) NPVR 80–89% (n = 283) NPVR 90–100% (n = 510) P Power (W) 400.0 (395.0, 400.0) 400.0 (400.0, 400.0) 400.0 (398.8, 400.0) 400.0 (400.0, 400.0) .060 Sonication time (s) 1200.0 (731.0, 1860.0) 1055 (536, 1554.5) 808.0 (520.0, 1375.0) 725.0 (471.5, 1099.8) < 0.001 Dose (KJ) 451.7 (265.0, 743.9) 426.8 (213.3, 623.8) 320.6 (192.0, 537.9) 286.8 (181.0, 438.4) < 0.001 NPVR (%) 53.0 (39.0, 61.0) 75.0 (72.0, 77.0) 84.0 (82.0, 87.0) 95.0 (92.0, 98.0) < 0.001 Note: Data are median value; interquartile range in brackets. Results and influencing factors of re-intervention in patients with NPVR ≥ 80% On the basis of the above result, 793 patients had an NPVR ≥ 80%, of which 581 were followed up successfully. The baseline characteristics and cumulative re-intervention rates are shown in Table 1 . Patient characteristics were analysed by Cox regression analysis to determine the influencing factors of re-intervention in patients with NPVR ≥ 80%. The results showed that age, BMI, history of lower abdominal surgery, history of childbirth, fibroids’ maximum diameter, volume, signal intensity on T 2 WI and enhancement type on T 1 WI were associated with re-intervention, while age of patients and signal intensity on T 2 WI of tumours were the independent risk factors. Elder patients and lower signal intensity on T2WI of fibroids may have a lower risk of re-intervention (Table 3 ). Table 3 The influencing factors of re-intervention at NPVR ≥ 80% with Cox regression analysis influencing factors B SE Wald P Exp(B) 95.0% CI Lower Upper age -0.096 0.019 24.668 <0.001 0.909 0.875 0.944 BMI -0.020 0.036 0.305 .581 0.980 0.913 1.052 History of lower abdominal surgery 0.357 0.205 3.037 .081 1.428 0.957 2.133 History of childbirth 0.324 0.269 1.453 .228 1.383 0.817 2.341 Maximum diameter of fibroids 0.002 0.012 0.041 .840 1.002 0.979 1.027 Volume of fibroids 0.000 0.000 1.025 .311 1.000 1.000 1.000 Signal intensity on T 2 WI 0.341 0.131 6.817 .009 1.407 1.089 1.817 Enhancement type on T 1 WI 0.179 0.142 1.588 .208 1.196 0.906 1.578 Discussion Uterine fibroids, as the most common benign tumours, still have a negative impact on the quality of life of women of childbearing age. Over the last decades, many studies have shown that USgHIFU, a completely non-invasive treatment technology, is safe and effective in the treatment of uterine ( 13 ). Previous studies showed that the re-intervention rate was 19.0% in 50 months (rang: 17–97) after USgHIFU ( 14 ) and 20.7% in 70 months (rang: 58–88) ( 15 ). Our study enrolled a total of more than 1,000 patients, which was significantly higher than those in previous single-centre reports. The cumulative re-intervention rate at 5 years was 16.8%, 22.6% at 8 years, and 24.1% at 10 years, which was comparable to the previous reports. Xu et al. ( 16 ) reported through a meta-analysis that the rate 5 years after a myomectomy was 19%. The long-term re-intervention rates of USgHIFU in our study was slightly lower than that of myomectomy. As an indicator of the success of USgHIFU technology, NPVR is important in the training of HIFU ablation technology, clinical treatment plan formulation and efficacy evaluation. A high NPVR reportedly corresponded to greater reduction in fibroids and increased symptom relief ( 17 , 18 ). Park et al. ( 19 ) reported that fibroids were reduced by 43% with NPVR > 80% after 3 months of MRgHIFU, while they were reduced by 20% with NPVR < 80%. The median NPVR of this study was 85.2%. Through the Kaplan-Meier survival curve for different NPVR groups, we found that a higher NPVR corresponded to a lower re-intervention rate with significant difference ( P < 0.001), which was similar to the results of previous studies. The five-year re-intervention rate was even less than 15% in the group of NPVR 80–89% (13.4%) and the group of NPVR 90–100% (10.7%), which was lower than in previous studies. Therefore, the long-term efficacy of USgHIFU is promising when it comes to higher NPVR. Interestingly, the long-term re-intervention rate was approximate between the group of NPVR 80–89% and the group of NPVR 90%, and the difference was not statistically significant ( P = 0.880). Furthermore, when NPVR is ≥ 80%, the cumulative re-intervention rates of 5, 8 and 10 years were 11.6%, 16.5% and 17.8%, respectively. Yoo et al. ( 20 ) reported the eight-year cumulative re-intervention rate was 16% after myomectomy. The long-term outcome of USgHIFU is comparable to that of myomectomy. Liu et al. ( 21 ) showed that an NPVR of 70% was considered an appropriate indicator of training qualification. Gong et al. ( 22 ) showed that experienced doctors can achieve 80% of NPVR when treating uterine fibroids and even more than 90% with more medical experience. In addition, some scholars investigated MRI screening parameters for predicting an NPV ratio of at least 90% ( 23 , 24 ). However, Gong et al. ( 25 ) showed that when NPVR was more than 90%, SIR-B lower abdominal pain was more likely to occur. The safety and intraoperative response of patients should be given attention while pursuing high NPVR during USgHIFU ablation. Therefore, NPVR ≥ 80% can be used as a marker of technical success, which means that NPVR should reach 80% as much as possible under the premise of ensuring safety. Among the 793 patients of NPVR ≥ 80%, 17.8% patients were still undergoing re-intervention. Cox regression was used for analysis to further clarify the influencing factors of long-term re-intervention in patients with technical success. Age and signal intensity on T 2 WI are independent risk factors. Older patients and lower signal intensity on T 2 WI of fibroids may indicate a lower risk of re-intervention. Numerous studies have confirmed that long-term re-intervention is negatively associated with age in both USgHIFU and myomectomy ( 13 , 15 , 26 ). The stimulating effects of oestrogen and progesterone on the growth of fibroids have been confirmed ( 27 ). Most fibroids can shrink or even disappear after menopause without intervention. Fibroid growth and recurrence occur easily in young people, while for elder patients, especially perimenopausal patients, fibroids can be temporarily left without intervention even if they recur. Hyperintense fibroids on T2WI in MRI have sparse collagen fibres and abundant cells ( 28 ), which do not easily deposit energy in USgHIFU. Therefore, this type of fibroids tends to have a low reduction rate and a high re-intervention rate ( 29 ). USgHIFU is a non-invasive treatment technique, in which the target dissolves, is absorbed or calcified because of the immune system, which means it cannot disappear immediately after USgHIFU ( 30 ). About 7.5% of patients chose re-intervention only because they have fibroids and do not experience any symptoms. Thus, a necessary step is to fully communicate with patients before the treatment to reduce their apprehension about USgHIFU ablation. Eight patients were diagnosed with thyroid cancer and 3 patients were diagnosed with breast cancer when we followed up. Thus, other health problems should also be given attention during health management. According to a large-cohort study, the incidence rate of adenomyosis was about 0.8% ( 31 ). Moreover, six patients (0.7%) were diagnosed with adenomyosis after USgHIFU, which could indicate that USgHIFU ablation for uterine fibroids does not increase the incidence of adenomyosis. This paper systematically reviewed eight years of case data, with a maximum follow-up time of up to 129 months. This long follow-up time can provide evidence of USgHIFU’s efficacy. NPVR ≥ 80%, which can be used as technical success, can provide a basis for predicting clinical efficacy. However, this study is a retrospective analysis with some possible recall bias due to the long-time interval. It is also limited because many patients did not complete the symptomatic evaluation. Thus, we could not report the score of symptomatic relief. More prospective studies are needed to validate this conclusion, and symptoms and quality of life should be assessed during follow-ups. A comparative study of myomectomy during the same period is recommended. Conclusion In conclusion, USgHIFU, as an alternative treatment of uterine fibroids, has a reliable long-term efficiency. NPVR ≥ 80% can reduce the long-term re-intervention rates of patients, which can be used as a sign of technical success. However, an important step is to assess before ablation, considering both age of patients and fibroids of signal intensity on T 2 WI. Declarations Ethics approval All patients signed informed consent forms before USgHIFU. Verbal consent was obtained for the follow-up. This retrospective study was approved by the ethics committee at our institution (Registration No. HF2023001; Date: 06/04/2023). The Chinese Clinical Trial Registry provided full approval for the study protocol (Registration No. CHiCTR2300074797; Date: 16/08/2023). All procedures were in accordance with ethical standards and the Declaration of Helsinki. Data availability statement The data that support the findings of this study are available on request from the corresponding author. The data are not publicly available due to their containing information that could compromise the privacy of research participants. Conflict of interest No potential conflict of interest was reported by the authors. Funding Natural Science Foundation of Chongqing [ cstc2021jcyj-msxmX0514 and CSTB2022NSCQ-MSX0140]. References Stewart EA, Cookson CL, Gandolfo RA, Schulze-Rath R. Epidemiology of uterine fibroids: a systematic review. BJOG : an international journal of obstetrics and gynaecology. 2017;124(10):1501-12. Stewart EA, Laughlin-Tommaso SK, Catherino WH, Lalitkumar S, Gupta D, Vollenhoven B. Uterine fibroids. 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Frontiers in medical technology. 2021;3:790956. Keserci B, Duc NM. Magnetic resonance imaging features influencing high-intensity focused ultrasound ablation of adenomyosis with a nonperfused volume ratio of ≥90% as a measure of clinical treatment success: retrospective multivariate analysis. International journal of hyperthermia : the official journal of European Society for Hyperthermic Oncology, North American Hyperthermia Group. 2018;35(1):626-36. Keserci B, Duc NM. Magnetic Resonance Imaging Parameters in Predicting the Treatment Outcome of High-intensity Focused Ultrasound Ablation of Uterine Fibroids With an Immediate Nonperfused Volume Ratio of at Least 90. Academic radiology. 2018;25(10):1257-69. Gong X, Liu D, Yang MJ, Zhang R, Chen WZ, Chen JY. Tolerance and efficacy of HIFU ablation for uterine fibroids NPVR ≥ 90%: a nested case-control study. International journal of hyperthermia : the official journal of European Society for Hyperthermic Oncology, North American Hyperthermia Group. 2022;39(1):946-51. Radosa MP, Owsianowski Z, Mothes A, Weisheit A, Vorwergk J, Asskaryar FA, et al. Long-term risk of fibroid recurrence after laparoscopic myomectomy. European journal of obstetrics, gynecology, and reproductive biology. 2014;180:35-9. Flake GP, Andersen J, Dixon D. Etiology and pathogenesis of uterine leiomyomas: a review. Environmental health perspectives. 2003;111(8):1037-54. Zhao WP, Chen JY, Chen WZ. Effect of biological characteristics of different types of uterine fibroids, as assessed with T2-weighted magnetic resonance imaging, on ultrasound-guided high-intensity focused ultrasound ablation. Ultrasound in medicine & biology. 2015;41(2):423-31. Zhao WP, Zhang J, Han ZY, Yao JP, Zhou X, Liang P. A clinical investigation treating different types of fibroids identified by MRI-T2WI imaging with ultrasound guided high intensity focused ultrasound. Scientific reports. 2017;7(1):10812. Stewart EA, Gedroyc WM, Tempany CM, Quade BJ, Inbar Y, Ehrenstein T, et al. Focused ultrasound treatment of uterine fibroid tumors: safety and feasibility of a noninvasive thermoablative technique. American journal of obstetrics and gynecology. 2003;189(1):48-54. Yu O, Schulze-Rath R, Grafton J, Hansen K, Scholes D, Reed SD. Adenomyosis incidence, prevalence and treatment: United States population-based study 2006-2015. American journal of obstetrics and gynecology. 2020;223(1):94.e1-.e10. Additional Declarations No competing interests reported. Supplementary Files SupplementalMaterial.docx Cite Share Download PDF Status: Under Review Version 1 posted Editorial decision: Revision requested 01 Apr, 2024 Reviews received at journal 12 Feb, 2024 Reviewers agreed at journal 11 Feb, 2024 Reviewers invited by journal 11 Feb, 2024 Editor assigned by journal 11 Feb, 2024 Editor invited by journal 16 Jan, 2024 Submission checks completed at journal 28 Dec, 2023 First submitted to journal 28 Dec, 2023 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. As a division of Research Square Company, we’re committed to making research communication faster, fairer, and more useful. We do this by developing innovative software and high quality services for the global research community. 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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-3817348","acceptedTermsAndConditions":true,"allowDirectSubmit":false,"archivedVersions":[],"articleType":"Research Article","associatedPublications":[],"authors":[{"id":264196745,"identity":"712cf0bd-b8da-4ddb-9438-f2357dbe1770","order_by":0,"name":"Shuang Li","email":"","orcid":"","institution":"Chongqing Medical University","correspondingAuthor":false,"prefix":"","firstName":"Shuang","middleName":"","lastName":"Li","suffix":""},{"id":264196747,"identity":"eba1b8bc-cfe1-4359-8e5b-3a33c3f56722","order_by":1,"name":"Meijie Yang","email":"","orcid":"","institution":"Chongqing Medical University","correspondingAuthor":false,"prefix":"","firstName":"Meijie","middleName":"","lastName":"Yang","suffix":""},{"id":264196748,"identity":"5dce0a4f-6597-439a-a34f-5bdb0909522f","order_by":2,"name":"Jingwen Yu","email":"","orcid":"","institution":"Chongqing Medical University","correspondingAuthor":false,"prefix":"","firstName":"Jingwen","middleName":"","lastName":"Yu","suffix":""},{"id":264196751,"identity":"02e80adc-9b9e-4f68-96b2-71faf233beee","order_by":3,"name":"Wangwa Ma","email":"","orcid":"","institution":"Chongqing Medical University","correspondingAuthor":false,"prefix":"","firstName":"Wangwa","middleName":"","lastName":"Ma","suffix":""},{"id":264196754,"identity":"6f215e93-39ea-4300-8d4e-125b30f1971a","order_by":4,"name":"Yongbin Deng","email":"","orcid":"","institution":"Chongqing Haifu Hospital","correspondingAuthor":false,"prefix":"","firstName":"Yongbin","middleName":"","lastName":"Deng","suffix":""},{"id":264196755,"identity":"79311b82-8ecc-49ae-9411-f4662860417b","order_by":5,"name":"Liang Hu","email":"","orcid":"","institution":"Chongqing Medical University","correspondingAuthor":false,"prefix":"","firstName":"Liang","middleName":"","lastName":"Hu","suffix":""},{"id":264196756,"identity":"e58b77e8-3bcc-450e-bb69-a4107a99309c","order_by":6,"name":"Jinyun Chen","email":"data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAZAAAAAyAQMAAABI0h/eAAAABlBMVEX///8AAABVwtN+AAAACXBIWXMAAA7EAAAOxAGVKw4bAAAAwklEQVRIiWNgGAWjYDACCTC2gfLYiNeSRqoWBobDJGjhn9187IFl23l5vmtnDBg+lB0GijQQsOTOsXQDybbbhjNv5xgwzjh3GChyAL8WA4kcMwmglgQDoBZm3rbDQJEEQlryvwG1nINo+Uuclhw2oJYDEC2MxGiRuJFmJiFxLhnol7SCgz3n0nkkbhDQwj8j+Zm0RJmdPN/t5I0PfpRZy/HPIKAFBJglQdFxAIwYeAirBwLGD38gWkbBKBgFo2AUYAUAQCZAqpgouHoAAAAASUVORK5CYII=","orcid":"","institution":"Chongqing Medical University","correspondingAuthor":true,"prefix":"","firstName":"Jinyun","middleName":"","lastName":"Chen","suffix":""}],"badges":[],"createdAt":"2023-12-28 15:14:17","currentVersionCode":1,"declarations":"","doi":"10.21203/rs.3.rs-3817348/v1","doiUrl":"https://doi.org/10.21203/rs.3.rs-3817348/v1","draftVersion":[],"editorialEvents":[],"editorialNote":"","failedWorkflow":false,"files":[{"id":49134083,"identity":"5a0de7e2-a73e-4910-a0df-f067bd718e69","added_by":"auto","created_at":"2024-01-03 16:49:48","extension":"jpg","order_by":1,"title":"Figure 1","display":"","copyAsset":false,"role":"figure","size":208380,"visible":true,"origin":"","legend":"\u003cp\u003eThe reasons of re-intervention\u003c/p\u003e","description":"","filename":"Figure1.jpg","url":"https://assets-eu.researchsquare.com/files/rs-3817348/v1/ec735515343052a2236d71ba.jpg"},{"id":49134085,"identity":"0c2a87ac-e450-43d9-a69a-43049e2e4218","added_by":"auto","created_at":"2024-01-03 16:49:48","extension":"jpg","order_by":2,"title":"Figure 2","display":"","copyAsset":false,"role":"figure","size":2647785,"visible":true,"origin":"","legend":"\u003cp\u003eThe MRI of fibroids in different NPVR (A1-D1) T2-weighted images of fibroids before USgHIFU; (A2-D2) Contrast enhanced MRI after USgHIFU; (A2) NPVR=30%; (B2) NPVR=73%; (C2) NPVR=88%; (D2) NPVR=100%.\u003c/p\u003e","description":"","filename":"Figure2.jpg","url":"https://assets-eu.researchsquare.com/files/rs-3817348/v1/0d443c0e47e3b8cb1a2c6ccf.jpg"},{"id":49134082,"identity":"24863792-2221-416b-8f3c-c51a975206ce","added_by":"auto","created_at":"2024-01-03 16:49:47","extension":"jpg","order_by":3,"title":"Figure 3","display":"","copyAsset":false,"role":"figure","size":256659,"visible":true,"origin":"","legend":"\u003cp\u003eCumulative rate of re-intervention after USgHIFU in different NPVR with Kaplan-Meier curve\u003c/p\u003e","description":"","filename":"Figure3.jpg","url":"https://assets-eu.researchsquare.com/files/rs-3817348/v1/fb15efcb7a529849352d5955.jpg"},{"id":49134582,"identity":"6cbe79fb-c400-4422-b279-0e438e5e9162","added_by":"auto","created_at":"2024-01-03 16:57:48","extension":"pdf","order_by":0,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":565947,"visible":true,"origin":"","legend":"","description":"","filename":"manuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-3817348/v1/2325fd33-c942-4698-afc9-d8b15f996759.pdf"},{"id":49134084,"identity":"bb747a9a-bd83-4c04-8557-258af130f85e","added_by":"auto","created_at":"2024-01-03 16:49:48","extension":"docx","order_by":5,"title":"","display":"","copyAsset":false,"role":"supplement","size":222459,"visible":true,"origin":"","legend":"","description":"","filename":"SupplementalMaterial.docx","url":"https://assets-eu.researchsquare.com/files/rs-3817348/v1/446a60877c3d8172e8b55e38.docx"}],"financialInterests":"No competing interests reported.","formattedTitle":"Achieving NPVR ≥ 80% as Technical Success of High-Intensity Focused Ultrasound Ablation for Uterine Fibroids: a cohort study","fulltext":[{"header":"Background","content":"\u003cp\u003eUterine fibroid, also known as leiomyoma, is the most common benign reproductive system tumours in females of childbearing age. The incidence rate of uterine fibroids ranges from 4.5\u0026ndash;68.6% due to population characteristics such as race, region, health status, etc.(\u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e) About 25% of women with uterine fibroids have clinical symptoms(\u003cspan citationid=\"CR2\" class=\"CitationRef\"\u003e2\u003c/span\u003e, \u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e3\u003c/span\u003e), such as menorrhagia, irregular bleeding, pelvic pain, or infertility(\u003cspan additionalcitationids=\"CR5\" citationid=\"CR4\" class=\"CitationRef\"\u003e4\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR6\" class=\"CitationRef\"\u003e6\u003c/span\u003e), which seriously affect women\u0026rsquo;s quality of life. Treatment options for uterine fibroids require individualised clinical management that considers both symptom relief and the patient\u0026rsquo;s desire to be pregnant. High-intensity focused ultrasound (HIFU) ablation could cause instant coagulative necrosis (1\u0026ndash;3 seconds) in a well-circumscribed area of 1.5 \u0026times; 1.5 \u0026times; 10 mm through focusing the ultrasound beam on the tumor, including ultrasound-guided high-intensity focused ultrasound (USgHIFU) ablation and magnetic resonance-guided high-intensity focused ultrasound (MRgHIFU) ablation (\u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e7\u003c/span\u003e). As a completely non-invasive treatment technology at present, it only damages the target area, thus being effective, safe and controllable (\u003cspan citationid=\"CR8\" class=\"CitationRef\"\u003e8\u003c/span\u003e).\u003c/p\u003e \u003cp\u003eThe non-perfusion volume (NPV) is the volume of area without perfusion on post-operative contrast-enhanced MRI within 3 days which was used to evaluate the therapeutic effectiveness. The non-perfusion volume ratio (NPVR), a predictor of re-intervention in the short to medium term, is defined as the proportion of non-perfusion volume to preoperative fibroid volume (\u003cspan citationid=\"CR9\" class=\"CitationRef\"\u003e9\u003c/span\u003e, \u003cspan citationid=\"CR10\" class=\"CitationRef\"\u003e10\u003c/span\u003e). Previous studies showed that the two-year clinical efficiency of USgHIFU was similar to that of myomectomy when NPVR is up to 70% (\u003cspan citationid=\"CR11\" class=\"CitationRef\"\u003e11\u003c/span\u003e). However, clinical evidence of the long-term efficacy of uterine fibroids after USgHIFU is still lacking. Therefore, the long-term efficacy of USgHIFU and re-intervention rates in different NPVR were explore. Furthermore, the influencing factors of long-term re-intervention in patients with NPVR\u0026thinsp;\u0026ge;\u0026thinsp;80% were analysed to provide a basis for an appropriate therapeutic regimen and case screening.\u003c/p\u003e"},{"header":"Methods","content":"\u003cdiv id=\"Sec3\" class=\"Section2\"\u003e \u003ch2\u003ePatients\u003c/h2\u003e \u003cp\u003ePatients with uterine fibroids who underwent USgHIFU in the Minimally Invasive and Noninvasive Treatment Centre of our hospital from January 2012 to December 2019 were enrolled.\u003c/p\u003e \u003cp\u003eThe inclusion criteria were as follows: (\u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e) premenopausal women between 18\u0026ndash;50 years old; (\u003cspan citationid=\"CR2\" class=\"CitationRef\"\u003e2\u003c/span\u003e) patients diagnosed with International Federation of Obstetrics and Gynecology Federation International of Gynecology and Obstetrics (FIGO) types 1\u0026ndash;6 uterine fibroids by magnetic resonance imaging (MRI); (\u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e3\u003c/span\u003e) the diameter of fibroid was at least 2 cm; (\u003cspan citationid=\"CR4\" class=\"CitationRef\"\u003e4\u003c/span\u003e) patients received fibroid-related treatment for the first time.\u003c/p\u003e \u003cp\u003eThe exclusion criteria were as follows: (\u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e) patients with a special type of fibroids, such as FIGO type 0, 7 or 8; (\u003cspan citationid=\"CR2\" class=\"CitationRef\"\u003e2\u003c/span\u003e) patients with other gynaecological diseases, such as adenomyosis and ovarian tumour; (\u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e3\u003c/span\u003e) patients with serious organic lesions, such as heart failure, liver cirrhosis, etc.; (\u003cspan citationid=\"CR4\" class=\"CitationRef\"\u003e4\u003c/span\u003e) patients diagnosed with or suspected to have a malignant disease, such as sarcoma of uterus; (\u003cspan citationid=\"CR5\" class=\"CitationRef\"\u003e5\u003c/span\u003e) patients unwilling to undergo follow-up.\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec4\" class=\"Section2\"\u003e \u003ch2\u003eUSgHIFU ablation\u003c/h2\u003e \u003cp\u003eOne-session USgHIFU ablation was performed by physicians with at least 3 years of HIFU clinical experience. A focused ultrasound tumour therapeutic system (Model-JC, Chongqing Haifu Medical Technology Co., Ltd., Chongqing, China) was used. The ultrasound transducer worked with a frequency of 0.5\u0026ndash;1.5 MHz, and energy was adjusted within a range of 350\u0026ndash;400 W. The guided ultrasound frequency used for real-time monitoring was 3.5 MHz (Esaote, MyLab70, Italy).\u003c/p\u003e \u003cp\u003eAll patients received diet preparation, enema cleansing and skin preparation (shaving, degreasing and degassing) before treatment. Fentanyl (0.8\u0026ndash;1 ug/kg) and midazolam hydrochloride (0.02\u0026ndash;0.03 mg/kg) were administered to maintain conscious sedation while reducing patient discomfort. The patients were prone on the HIFU table with their anterior abdominal wall in contact with degassed water. An adjustable water balloon was placed between the abdominal wall and transducer when it was necessary in case the bowel blocked the acoustic pathway. The treatment focuses were at least 15 mm from the endometrium and 10 mm from the perimetrium. The ultrasonic sonication time and acoustic power were adjusted based on the change in patient tolerance and the target area. Greyscale changes in real-time ultrasonographic imaging served as the ablation marker. The sonication was terminated when the increased greyscale covered the planned ablation area, and sonication time was controlled within 3000s. The patients were instructed to remain in the prone position for 2 hours after procedure.\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec5\" class=\"Section2\"\u003e \u003ch2\u003eMRI evaluation and classification\u003c/h2\u003e \u003cp\u003eAll patients received an MRI scan 1 week before and within 3 days after the treatment. T\u003csub\u003e1\u003c/sub\u003eWI, T\u003csub\u003e2\u003c/sub\u003eWI and enhanced T\u003csub\u003e1\u003c/sub\u003eWI was performed with a 3.0-T MRI system (Singa HD Excite, GE Healthcare, USA). The MR images were analyzed by a radiologist who had completed 5 years of specialization in abdominal MR imaging (Reader 1) and they were validated by another radiologist (Reader 2) who had 15 years of experience in abdominal MR imaging; in case of disagreement, Reader 2 retraced the image and this was considered as the final decision.\u003c/p\u003e \u003cp\u003eThe MR images were evaluated and measured as follows: (\u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e) Type of fibroid: types 1\u0026ndash;6. The fibroids were categorised according to the FIGO (\u003cspan citationid=\"CR12\" class=\"CitationRef\"\u003e12\u003c/span\u003e). (\u003cspan citationid=\"CR2\" class=\"CitationRef\"\u003e2\u003c/span\u003e) Location of fibroids: anterior or posterior. The fibroid that the acoustic pathway did not pass through the uterine cavity during USgHIFU ablation was an anterior fibroid. Otherwise, it was a posterior fibroid. (\u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e3\u003c/span\u003e) Signal intensity on T\u003csub\u003e2\u003c/sub\u003eWI: hypointense, isointense or hyperintense. (\u003cspan citationid=\"CR4\" class=\"CitationRef\"\u003e4\u003c/span\u003e) Enhancement type on T\u003csub\u003e1\u003c/sub\u003eWI: mild, moderate or significant. The degree of enhancement was compared with normal myometrium according to the dynamic contrast-enhanced MR image within 60 s of contrast medium injection. (\u003cspan citationid=\"CR5\" class=\"CitationRef\"\u003e5\u003c/span\u003e) Maximum diameter of fibroids: Three dimensions were measured on T\u003csub\u003e2\u003c/sub\u003eWI before the treatment: longitudinal diameter (D\u003csub\u003e1\u003c/sub\u003e), anteroposterior diameter (D\u003csub\u003e2\u003c/sub\u003e) and transverse diameter (D\u003csub\u003e3\u003c/sub\u003e). The maximum of the three dimensions was selected as the maximum diameter of fibroids. (\u003cspan citationid=\"CR6\" class=\"CitationRef\"\u003e6\u003c/span\u003e) Calculation of fibroid volumes and NPVR: The volume was calculated by using the following equation: \u003cem\u003eV\u003c/em\u003e\u0026thinsp;=\u0026thinsp;0.5233 \u0026times; D\u003csub\u003e1\u003c/sub\u003e \u0026times; D\u003csub\u003e2\u003c/sub\u003e \u0026times; D\u003csub\u003e3\u003c/sub\u003e. (\u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e7\u003c/span\u003e) Calculation of NPVR: NPV was evaluated according to the formula above on enhanced T\u003csub\u003e1\u003c/sub\u003eWI after the treatment. NPVR was defined as NPV / post-treatment fibroid volume \u0026times; 100%.\u003c/p\u003e \u003c/div\u003e\n\u003ch3\u003eFollow-up\u003c/h3\u003e\n\u003cp\u003eA gynecologist who had worked for more than 3-year experience followed up visit to the patients by telephone according to the follow-up content and criteria set by our research team. If the patients had undergone re-intervention, the method, as well as the reason and time, needed to be recorded. Surgical treatment due to uterine fibroids was defined as re-intervention, such as myomectomy, USgHIFU, hysterectomy and UAE. Patients who were diagnosed with adenomyosis or malignant disease were also followed up. The follow-up end point is set by re-intervention for fibroids and hysterectomy for other reasons. If patients were unable to be contacted multiple times within 3 days, they were confirmed as lost to follow-up.\u003c/p\u003e \u003cdiv id=\"Sec7\" class=\"Section2\"\u003e \u003ch2\u003eStatistical analysis\u003c/h2\u003e \u003cp\u003eSPSS version 26.0 (IBM, Armonk, NY, USA) was used for statistical analysis. Normally distributed data were reported as mean\u0026thinsp;\u0026plusmn;\u0026thinsp;standard deviation (SD), and non-normally distributed data were reported as medians and interquartile range. Categorical data were expressed as numerals and percentages (%). Comparisons among groups were conducted using multiple-factor analysis of variance, Mann-Whitney U test, Kruskal-Wallis test, chi-square test, continuous correction test and Fisher\u0026rsquo;s exact test, with a \u003cem\u003eP\u003c/em\u003e value less than 0.05 considered as significant. Kaplan-Meier survival curve was used to explore cumulative re-intervention rates, and Cox regression was used to analyse the influencing factors.\u003c/p\u003e \u003c/div\u003e"},{"header":"Results","content":"\u003cdiv id=\"Sec9\" class=\"Section2\"\u003e \u003ch2\u003eBaseline characteristics of patients and Long-term efficacy of USgHIFU\u003c/h2\u003e \u003cp\u003eA total of 1,257 patients were enrolled, of which 920 patients were successfully followed up while 337 patients (26.8%) were lost. The patients\u0026rsquo; median age was 39.0 years (IQR 33.0, 43.0), and median BMI was 22.0 kg/m\u003csup\u003e2\u003c/sup\u003e (IQR 20.4, 23.8). The maximum diameter of uterine fibroids was 56.0 mm (47.0, 68.0), and the volume of fibroids was 71.0 cm\u003csup\u003e3\u003c/sup\u003e (42.0, 122.4). Other baseline characteristics are given in Table\u0026nbsp;\u003cspan refid=\"Tab1\" class=\"InternalRef\"\u003e1\u003c/span\u003e.\u003c/p\u003e \u003cp\u003e \u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab1\" border=\"1\"\u003e \u003ccaption language=\"En\"\u003e \u003cdiv class=\"CaptionNumber\"\u003eTable 1\u003c/div\u003e \u003cdiv class=\"CaptionContent\"\u003e \u003cp\u003eBaseline characteristics of patients and cumulative re-intervention rates\u003c/p\u003e \u003c/div\u003e \u003c/caption\u003e \u003ccolgroup cols=\"3\"\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e \u003cthead\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c1\"\u003e \u003cp\u003eVariable\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c2\"\u003e \u003cp\u003eTotal patients\u003c/p\u003e \u003cp\u003e(n\u0026thinsp;=\u0026thinsp;1257)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c3\"\u003e \u003cp\u003ePatients of NPVR\u0026thinsp;\u0026ge;\u0026thinsp;80%\u003c/p\u003e \u003cp\u003e(n\u0026thinsp;=\u0026thinsp;793)\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003c/thead\u003e \u003ctbody\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eNumber of successful follow-up cases (n)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e920\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e581\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eGeneral patient data\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eAge (years)\u003csup\u003e*\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e39.0 (33.0, 43.0)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e39.0 (33.0, 43.0)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eBMI (kg/m\u003csup\u003e2\u003c/sup\u003e)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e22.0 (20.4, 23.8)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e22.0 (20.3, 23.7)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eFamily history of fibroids (yes/no) (n)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e82/1175\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e58/735\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eHistory of smoking or drinking (yes/no) (n)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e76/1181\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e49/744\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eHistory of lower abdominal surgery (yes/no) (n)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e427/830\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e258/525\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eHistory of childbirth (yes/no) (n)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e920/337\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e582/211\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eFibroid data of MR imaging\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eType (Ⅰ-Ⅱ/Ⅲ-Ⅳ/Ⅴ-Ⅵ) (n)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e143/236/878\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e92/148/553\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eLocation (anterior/posterior) (\u003cem\u003en\u003c/em\u003e)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e860/397\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e567/226\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eSignal intensity on T\u003csub\u003e2\u003c/sub\u003eWI (hypointense/isointense/hyperintense) (n)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e407/355/495\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e303/235/255\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eEnhancement type on T\u003csub\u003e1\u003c/sub\u003eWI of fibroids\u003c/p\u003e \u003cp\u003e(mild / moderate / significant) (n)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e417/560/280\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e297/347/149\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eMaximum diameter (mm)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e56.0 (47.0, 68.0)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e56.0 (47.0, 67.0)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eVolume (cm\u003csup\u003e3\u003c/sup\u003e)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e71.0 (42.0, 122.4)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e71.3 (42.3, 120.7)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eCumulative re-intervention rate (%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e1 years\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e3.4\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e1.3\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e3 years\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e11.8\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e7.4\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e5 years\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e16.8\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e11.6\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e8 years\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e22.6\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e16.5\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e10 years\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e24.1\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e17.8\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003c/tbody\u003e \u003c/colgroup\u003e \u003ctfoot\u003e \u003ctr\u003e\u003ctd colspan=\"3\"\u003eNote: Data are median value; interquartile range in brackets.\u003c/td\u003e\u003c/tr\u003e \u003c/tfoot\u003e \u003c/table\u003e\u003c/div\u003e \u003c/p\u003e \u003cp\u003eThe median power of USgHIFU ablation was 400.0 W (IQR 399.8 W, 400 W), the median sonication time was 880.0 seconds (IQR 521.0 seconds, 1403.8 seconds), the median dose was 342.8 KJ (IQR 200.0 KJ, 550.0 KJ) and the median NPVR was 85.2% (IQR 71.6%, 93.8%). No SIR C-F complications such as skin burn and intestinal injury etc., and no long-term complications related to USgHIFU occurred during and after treatment. The median follow-up time after USgHIFU was 88 months (IQR 67, 110), ranging from 45 to 129 months. The cumulative re-intervention rates 1, 3, 5, 8, and 10 years after USgHIFU were 3.4%, 11.8%, 16.8%, 22.6% and 24.1% as indicated by survival analysis (Table\u0026nbsp;\u003cspan refid=\"Tab1\" class=\"InternalRef\"\u003e1\u003c/span\u003e). The main reason for re-intervention was re-enlargement of original fibroids (48.8%, 124/254), followed by symptom recurrence (15.7%, 40/254); removing fibroids during other surgeries such as caesarean section (9.8%, 25/254); new fibroids 9.8%, 25/254); poor ablation (5.9%, 15/254); psychological factors due to the follow-up image of ablated residual fibroid, which was asymptomatic and did not grow (4.3%, 11/254); pre-fertility preparation (3.9%, 10/254); and hysteroscopic surgery because of submucosal fibroids expelled (1.6%, 4/254) (Fig.\u0026nbsp;\u003cspan refid=\"Fig1\" class=\"InternalRef\"\u003e1\u003c/span\u003e). Re-intervention methods included myomectomy (68.5%, 174/254), USgHIFU (17.7%, 45/254), hysterectomy (13.4%, 34/254) and UAE (0.4%, 1/382). In addition, six patients (0.7%) were diagnosed with adenomyosis after USgHIFU. Eight patients were diagnosed with thyroid cancer, and three patients were diagnosed with breast cancer when we followed up.\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec10\" class=\"Section2\"\u003e \u003ch2\u003eCumulative re-intervention in different NPVR groups\u003c/h2\u003e \u003cp\u003eThe patients were divided into four groups according to different NPVR: \u0026lt;70% (275/1275), 70\u0026ndash;79% (189/1275), 80\u0026ndash;89% (283/1275) and 90\u0026ndash;100% (510/1275) (Fig.\u0026nbsp;\u003cspan refid=\"Fig2\" class=\"InternalRef\"\u003e2\u003c/span\u003e). The sonication time and dose of NPVR 90%-100% group were significant lower than those of other groups (\u003cem\u003eP\u003c/em\u003e\u0026thinsp;\u0026lt;\u0026thinsp;0.001) (Table\u0026nbsp;\u003cspan refid=\"Tab2\" class=\"InternalRef\"\u003e2\u003c/span\u003e). The Kaplan-Meier survival curve indicated that the group of NPVR 90\u0026ndash;100% had the lowest re-intervention rate (17.9%), followed by the group of NPVR 80\u0026ndash;89% (18.3%), the group of NPVR 70\u0026ndash;79% (31.1%), and the group of NPVR\u0026thinsp;\u0026lt;\u0026thinsp;70%, which had the highest re-intervention rate (37.4%), with significant differences (\u003cem\u003eP\u003c/em\u003e\u0026thinsp;\u0026lt;\u0026thinsp;0.001). However, a comparison between the group of NPVR 80\u0026ndash;89% and the group of NPVR 90\u0026ndash;100% showed no significant differences in long-term re-intervention rates (\u003cem\u003eP\u003c/em\u003e\u0026thinsp;=\u0026thinsp;0.499) (Fig.\u0026nbsp;\u003cspan refid=\"Fig3\" class=\"InternalRef\"\u003e3\u003c/span\u003e).\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003cp\u003e \u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab2\" border=\"1\"\u003e \u003ccaption language=\"En\"\u003e \u003cdiv class=\"CaptionNumber\"\u003eTable 2\u003c/div\u003e \u003cdiv class=\"CaptionContent\"\u003e \u003cp\u003eThe ablation results of USgHIFU in different NPVR\u003c/p\u003e \u003c/div\u003e \u003c/caption\u003e \u003ccolgroup cols=\"6\"\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c4\" colnum=\"4\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c5\" colnum=\"5\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c6\" colnum=\"6\"\u003e\u003c/div\u003e \u003cthead\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c1\"\u003e \u003cp\u003eVariable\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c2\"\u003e \u003cp\u003eNPVR\u0026thinsp;\u0026lt;\u0026thinsp;70%\u003c/p\u003e \u003cp\u003e(n\u0026thinsp;=\u0026thinsp;275)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c3\"\u003e \u003cp\u003eNPVR 70\u0026ndash;79%\u003c/p\u003e \u003cp\u003e(n\u0026thinsp;=\u0026thinsp;189)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c4\"\u003e \u003cp\u003eNPVR 80\u0026ndash;89%\u003c/p\u003e \u003cp\u003e(n\u0026thinsp;=\u0026thinsp;283)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c5\"\u003e \u003cp\u003eNPVR 90\u0026ndash;100%\u003c/p\u003e \u003cp\u003e(n\u0026thinsp;=\u0026thinsp;510)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c6\"\u003e \u003cp\u003e\u003cem\u003eP\u003c/em\u003e\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003c/thead\u003e \u003ctbody\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003ePower (W)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e400.0 (395.0, 400.0)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e400.0 (400.0, 400.0)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e400.0 (398.8, 400.0)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e400.0 (400.0, 400.0)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e.060\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eSonication time (s)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e1200.0 (731.0, 1860.0)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e1055 (536, 1554.5)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e808.0 (520.0, 1375.0)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e725.0 (471.5, 1099.8)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e\u0026lt;\u0026thinsp;0.001\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eDose (KJ)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e451.7 (265.0, 743.9)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e426.8 (213.3, 623.8)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e320.6 (192.0, 537.9)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e286.8 (181.0, 438.4)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e\u0026lt;\u0026thinsp;0.001\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eNPVR (%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e53.0 (39.0, 61.0)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e75.0 (72.0, 77.0)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e84.0 (82.0, 87.0)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e95.0 (92.0, 98.0)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e\u0026lt;\u0026thinsp;0.001\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003c/tbody\u003e \u003c/colgroup\u003e \u003ctfoot\u003e \u003ctr\u003e\u003ctd colspan=\"6\"\u003eNote: Data are median value; interquartile range in brackets.\u003c/td\u003e\u003c/tr\u003e \u003c/tfoot\u003e \u003c/table\u003e\u003c/div\u003e \u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec11\" class=\"Section2\"\u003e \u003ch2\u003eResults and influencing factors of re-intervention in patients with NPVR\u0026thinsp;\u0026ge;\u0026thinsp;80%\u003c/h2\u003e \u003cp\u003eOn the basis of the above result, 793 patients had an NPVR\u0026thinsp;\u0026ge;\u0026thinsp;80%, of which 581 were followed up successfully. The baseline characteristics and cumulative re-intervention rates are shown in Table\u0026nbsp;\u003cspan refid=\"Tab1\" class=\"InternalRef\"\u003e1\u003c/span\u003e.\u003c/p\u003e \u003cp\u003ePatient characteristics were analysed by Cox regression analysis to determine the influencing factors of re-intervention in patients with NPVR\u0026thinsp;\u0026ge;\u0026thinsp;80%. The results showed that age, BMI, history of lower abdominal surgery, history of childbirth, fibroids\u0026rsquo; maximum diameter, volume, signal intensity on T\u003csub\u003e2\u003c/sub\u003eWI and enhancement type on T\u003csub\u003e1\u003c/sub\u003eWI were associated with re-intervention, while age of patients and signal intensity on T\u003csub\u003e2\u003c/sub\u003eWI of tumours were the independent risk factors. Elder patients and lower signal intensity on T2WI of fibroids may have a lower risk of re-intervention (Table\u0026nbsp;\u003cspan refid=\"Tab3\" class=\"InternalRef\"\u003e3\u003c/span\u003e).\u003c/p\u003e \u003cp\u003e \u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab3\" border=\"1\"\u003e \u003ccaption language=\"En\"\u003e \u003cdiv class=\"CaptionNumber\"\u003eTable 3\u003c/div\u003e \u003cdiv class=\"CaptionContent\"\u003e \u003cp\u003eThe influencing factors of re-intervention at NPVR\u0026thinsp;\u0026ge;\u0026thinsp;80% with Cox regression analysis\u003c/p\u003e \u003c/div\u003e \u003c/caption\u003e \u003ccolgroup cols=\"8\"\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c4\" colnum=\"4\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c5\" colnum=\"5\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c6\" colnum=\"6\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c7\" colnum=\"7\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c8\" colnum=\"8\"\u003e\u003c/div\u003e \u003cthead\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c1\" morerows=\"1\" rowspan=\"2\"\u003e \u003cp\u003einfluencing factors\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c2\" morerows=\"1\" rowspan=\"2\"\u003e \u003cp\u003eB\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c3\" morerows=\"1\" rowspan=\"2\"\u003e \u003cp\u003eSE\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c4\" morerows=\"1\" rowspan=\"2\"\u003e \u003cp\u003eWald\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c5\" morerows=\"1\" rowspan=\"2\"\u003e \u003cp\u003e\u003cem\u003eP\u003c/em\u003e\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c6\" morerows=\"1\" rowspan=\"2\"\u003e \u003cp\u003eExp(B)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colspan=\"2\" nameend=\"c8\" namest=\"c7\"\u003e \u003cp\u003e95.0% CI\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c7\"\u003e \u003cp\u003eLower\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c8\"\u003e \u003cp\u003eUpper\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003c/thead\u003e \u003ctbody\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eage\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e-0.096\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e0.019\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e24.668\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e\u003c0.001\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e \u003cp\u003e0.909\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e \u003cp\u003e0.875\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c8\"\u003e \u003cp\u003e0.944\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eBMI\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e-0.020\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e0.036\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e0.305\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e.581\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e \u003cp\u003e0.980\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e \u003cp\u003e0.913\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c8\"\u003e \u003cp\u003e1.052\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eHistory of lower abdominal surgery\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e0.357\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e0.205\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e3.037\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e.081\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e \u003cp\u003e1.428\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e \u003cp\u003e0.957\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c8\"\u003e \u003cp\u003e2.133\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eHistory of childbirth\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e0.324\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e0.269\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e1.453\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e.228\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e \u003cp\u003e1.383\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e \u003cp\u003e0.817\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c8\"\u003e \u003cp\u003e2.341\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eMaximum diameter of fibroids\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e0.002\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e0.012\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e0.041\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e.840\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e \u003cp\u003e1.002\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e \u003cp\u003e0.979\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c8\"\u003e \u003cp\u003e1.027\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eVolume of fibroids\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e0.000\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e0.000\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e1.025\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e.311\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e \u003cp\u003e1.000\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e \u003cp\u003e1.000\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c8\"\u003e \u003cp\u003e1.000\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eSignal intensity on T\u003csub\u003e2\u003c/sub\u003eWI\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e0.341\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e0.131\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e6.817\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e.009\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e \u003cp\u003e1.407\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e \u003cp\u003e1.089\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c8\"\u003e \u003cp\u003e1.817\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eEnhancement type on T\u003csub\u003e1\u003c/sub\u003eWI\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e0.179\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e0.142\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e1.588\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e.208\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e \u003cp\u003e1.196\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e \u003cp\u003e0.906\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c8\"\u003e \u003cp\u003e1.578\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003c/tbody\u003e \u003c/colgroup\u003e \u003c/table\u003e\u003c/div\u003e \u003c/p\u003e \u003c/div\u003e"},{"header":"Discussion","content":"\u003cp\u003eUterine fibroids, as the most common benign tumours, still have a negative impact on the quality of life of women of childbearing age. Over the last decades, many studies have shown that USgHIFU, a completely non-invasive treatment technology, is safe and effective in the treatment of uterine (\u003cspan citationid=\"CR13\" class=\"CitationRef\"\u003e13\u003c/span\u003e). Previous studies showed that the re-intervention rate was 19.0% in 50 months (rang: 17\u0026ndash;97) after USgHIFU (\u003cspan citationid=\"CR14\" class=\"CitationRef\"\u003e14\u003c/span\u003e) and 20.7% in 70 months (rang: 58\u0026ndash;88) (\u003cspan citationid=\"CR15\" class=\"CitationRef\"\u003e15\u003c/span\u003e). Our study enrolled a total of more than 1,000 patients, which was significantly higher than those in previous single-centre reports. The cumulative re-intervention rate at 5 years was 16.8%, 22.6% at 8 years, and 24.1% at 10 years, which was comparable to the previous reports. Xu et al. (\u003cspan citationid=\"CR16\" class=\"CitationRef\"\u003e16\u003c/span\u003e) reported through a meta-analysis that the rate 5 years after a myomectomy was 19%. The long-term re-intervention rates of USgHIFU in our study was slightly lower than that of myomectomy.\u003c/p\u003e \u003cp\u003eAs an indicator of the success of USgHIFU technology, NPVR is important in the training of HIFU ablation technology, clinical treatment plan formulation and efficacy evaluation. A high NPVR reportedly corresponded to greater reduction in fibroids and increased symptom relief (\u003cspan citationid=\"CR17\" class=\"CitationRef\"\u003e17\u003c/span\u003e, \u003cspan citationid=\"CR18\" class=\"CitationRef\"\u003e18\u003c/span\u003e). Park et al. (\u003cspan citationid=\"CR19\" class=\"CitationRef\"\u003e19\u003c/span\u003e) reported that fibroids were reduced by 43% with NPVR\u0026thinsp;\u0026gt;\u0026thinsp;80% after 3 months of MRgHIFU, while they were reduced by 20% with NPVR\u0026thinsp;\u0026lt;\u0026thinsp;80%. The median NPVR of this study was 85.2%. Through the Kaplan-Meier survival curve for different NPVR groups, we found that a higher NPVR corresponded to a lower re-intervention rate with significant difference (\u003cem\u003eP\u003c/em\u003e\u0026thinsp;\u0026lt;\u0026thinsp;0.001), which was similar to the results of previous studies. The five-year re-intervention rate was even less than 15% in the group of NPVR 80\u0026ndash;89% (13.4%) and the group of NPVR 90\u0026ndash;100% (10.7%), which was lower than in previous studies. Therefore, the long-term efficacy of USgHIFU is promising when it comes to higher NPVR. Interestingly, the long-term re-intervention rate was approximate between the group of NPVR 80\u0026ndash;89% and the group of NPVR 90%, and the difference was not statistically significant (\u003cem\u003eP\u003c/em\u003e\u0026thinsp;=\u0026thinsp;0.880). Furthermore, when NPVR is \u0026ge;\u0026thinsp;80%, the cumulative re-intervention rates of 5, 8 and 10 years were 11.6%, 16.5% and 17.8%, respectively. Yoo et al. (\u003cspan citationid=\"CR20\" class=\"CitationRef\"\u003e20\u003c/span\u003e) reported the eight-year cumulative re-intervention rate was 16% after myomectomy. The long-term outcome of USgHIFU is comparable to that of myomectomy. Liu et al. (\u003cspan citationid=\"CR21\" class=\"CitationRef\"\u003e21\u003c/span\u003e) showed that an NPVR of 70% was considered an appropriate indicator of training qualification. Gong et al. (\u003cspan citationid=\"CR22\" class=\"CitationRef\"\u003e22\u003c/span\u003e) showed that experienced doctors can achieve 80% of NPVR when treating uterine fibroids and even more than 90% with more medical experience. In addition, some scholars investigated MRI screening parameters for predicting an NPV ratio of at least 90% (\u003cspan citationid=\"CR23\" class=\"CitationRef\"\u003e23\u003c/span\u003e, \u003cspan citationid=\"CR24\" class=\"CitationRef\"\u003e24\u003c/span\u003e). However, Gong et al. (\u003cspan citationid=\"CR25\" class=\"CitationRef\"\u003e25\u003c/span\u003e) showed that when NPVR was more than 90%, SIR-B lower abdominal pain was more likely to occur. The safety and intraoperative response of patients should be given attention while pursuing high NPVR during USgHIFU ablation. Therefore, NPVR\u0026thinsp;\u0026ge;\u0026thinsp;80% can be used as a marker of technical success, which means that NPVR should reach 80% as much as possible under the premise of ensuring safety.\u003c/p\u003e \u003cp\u003eAmong the 793 patients of NPVR\u0026thinsp;\u0026ge;\u0026thinsp;80%, 17.8% patients were still undergoing re-intervention. Cox regression was used for analysis to further clarify the influencing factors of long-term re-intervention in patients with technical success. Age and signal intensity on T\u003csub\u003e2\u003c/sub\u003eWI are independent risk factors. Older patients and lower signal intensity on T\u003csub\u003e2\u003c/sub\u003eWI of fibroids may indicate a lower risk of re-intervention. Numerous studies have confirmed that long-term re-intervention is negatively associated with age in both USgHIFU and myomectomy (\u003cspan citationid=\"CR13\" class=\"CitationRef\"\u003e13\u003c/span\u003e, \u003cspan citationid=\"CR15\" class=\"CitationRef\"\u003e15\u003c/span\u003e, \u003cspan citationid=\"CR26\" class=\"CitationRef\"\u003e26\u003c/span\u003e). The stimulating effects of oestrogen and progesterone on the growth of fibroids have been confirmed (\u003cspan citationid=\"CR27\" class=\"CitationRef\"\u003e27\u003c/span\u003e). Most fibroids can shrink or even disappear after menopause without intervention. Fibroid growth and recurrence occur easily in young people, while for elder patients, especially perimenopausal patients, fibroids can be temporarily left without intervention even if they recur. Hyperintense fibroids on T2WI in MRI have sparse collagen fibres and abundant cells (\u003cspan citationid=\"CR28\" class=\"CitationRef\"\u003e28\u003c/span\u003e), which do not easily deposit energy in USgHIFU. Therefore, this type of fibroids tends to have a low reduction rate and a high re-intervention rate (\u003cspan citationid=\"CR29\" class=\"CitationRef\"\u003e29\u003c/span\u003e).\u003c/p\u003e \u003cp\u003eUSgHIFU is a non-invasive treatment technique, in which the target dissolves, is absorbed or calcified because of the immune system, which means it cannot disappear immediately after USgHIFU (\u003cspan citationid=\"CR30\" class=\"CitationRef\"\u003e30\u003c/span\u003e). About 7.5% of patients chose re-intervention only because they have fibroids and do not experience any symptoms. Thus, a necessary step is to fully communicate with patients before the treatment to reduce their apprehension about USgHIFU ablation.\u003c/p\u003e \u003cp\u003eEight patients were diagnosed with thyroid cancer and 3 patients were diagnosed with breast cancer when we followed up. Thus, other health problems should also be given attention during health management. According to a large-cohort study, the incidence rate of adenomyosis was about 0.8% (\u003cspan citationid=\"CR31\" class=\"CitationRef\"\u003e31\u003c/span\u003e). Moreover, six patients (0.7%) were diagnosed with adenomyosis after USgHIFU, which could indicate that USgHIFU ablation for uterine fibroids does not increase the incidence of adenomyosis.\u003c/p\u003e \u003cp\u003eThis paper systematically reviewed eight years of case data, with a maximum follow-up time of up to 129 months. This long follow-up time can provide evidence of USgHIFU\u0026rsquo;s efficacy. NPVR\u0026thinsp;\u0026ge;\u0026thinsp;80%, which can be used as technical success, can provide a basis for predicting clinical efficacy.\u003c/p\u003e \u003cp\u003eHowever, this study is a retrospective analysis with some possible recall bias due to the long-time interval. It is also limited because many patients did not complete the symptomatic evaluation. Thus, we could not report the score of symptomatic relief. More prospective studies are needed to validate this conclusion, and symptoms and quality of life should be assessed during follow-ups. A comparative study of myomectomy during the same period is recommended.\u003c/p\u003e"},{"header":"Conclusion","content":"\u003cp\u003eIn conclusion, USgHIFU, as an alternative treatment of uterine fibroids, has a reliable long-term efficiency. NPVR\u0026thinsp;\u0026ge;\u0026thinsp;80% can reduce the long-term re-intervention rates of patients, which can be used as a sign of technical success. However, an important step is to assess before ablation, considering both age of patients and fibroids of signal intensity on T\u003csub\u003e2\u003c/sub\u003eWI.\u003c/p\u003e"},{"header":"Declarations","content":"\u003cp\u003e\u003cstrong\u003eEthics approval\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eAll patients signed informed consent forms before USgHIFU. Verbal consent was obtained for the follow-up.\u0026nbsp;This retrospective study was approved by the ethics committee at our institution (Registration\u0026nbsp;No. HF2023001; Date: 06/04/2023). The Chinese Clinical Trial Registry provided full approval for the study protocol\u0026nbsp;(Registration\u0026nbsp;No.\u0026nbsp;CHiCTR2300074797;\u0026nbsp;Date: 16/08/2023).\u0026nbsp;All procedures were in accordance with ethical standards and the Declaration of Helsinki.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eData availability statement\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe data that support the findings of this study are available on request from the corresponding author. The data are not publicly available due to their containing information that could compromise the privacy of research participants.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eConflict of interest\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eNo potential conflict of interest was reported by the authors.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eFunding\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eNatural Science Foundation of Chongqing [ cstc2021jcyj-msxmX0514 and CSTB2022NSCQ-MSX0140].\u003c/p\u003e"},{"header":"References","content":"\u003col\u003e\n\u003cli\u003eStewart EA, Cookson CL, Gandolfo RA, Schulze-Rath R. Epidemiology of uterine fibroids: a systematic review. BJOG : an international journal of obstetrics and gynaecology. 2017;124(10):1501-12.\u003c/li\u003e\n\u003cli\u003eStewart EA, Laughlin-Tommaso SK, Catherino WH, Lalitkumar S, Gupta D, Vollenhoven B. Uterine fibroids. Nature reviews Disease primers. 2016;2:16043.\u003c/li\u003e\n\u003cli\u003eIslam MS, Protic O, Stortoni P, Grechi G, Lamanna P, Petraglia F, et al. Complex networks of multiple factors in the pathogenesis of uterine leiomyoma. Fertility and sterility. 2013;100(1):178-93.\u003c/li\u003e\n\u003cli\u003eOsuga Y, Nakano Y, Yamauchi Y, Takanashi M. Ulipristal acetate compared with leuprorelin acetate for Japanese women with symptomatic uterine fibroids: a phase III randomized controlled trial. Fertility and sterility. 2021;116(1):189-97.\u003c/li\u003e\n\u003cli\u003eAli M, A RS, Al Hendy A. Elagolix in the treatment of heavy menstrual bleeding associated with uterine fibroids in premenopausal women. Expert review of clinical pharmacology. 2021;14(4):427-37.\u003c/li\u003e\n\u003cli\u003eHerrmann A, Torres-de la Roche LA, Krentel H, Cezar C, de Wilde MS, Devassy R, et al. Adhesions after Laparoscopic Myomectomy: Incidence, Risk Factors, Complications, and Prevention. Gynecology and minimally invasive therapy. 2020;9(4):190-7.\u003c/li\u003e\n\u003cli\u003eChen J, Li Y, Wang Z, McCulloch P, Hu L, Chen W, et al. Evaluation of high-intensity focused ultrasound ablation for uterine fibroids: an IDEAL prospective exploration study. BJOG : an international journal of obstetrics and gynaecology. 2018;125(3):354-64.\u003c/li\u003e\n\u003cli\u003eJacoby VL, Kohi MP, Poder L, Jacoby A, Lager J, Schembri M, et al. PROMISe trial: a pilot, randomized, placebo-controlled trial of magnetic resonance guided focused ultrasound for uterine fibroids. Fertility and sterility. 2016;105(3):773-80.\u003c/li\u003e\n\u003cli\u003eFunaki K, Fukunishi H, Funaki T, Sawada K, Kaji Y, Maruo T. Magnetic resonance-guided focused ultrasound surgery for uterine fibroids: relationship between the therapeutic effects and signal intensity of preexisting T2-weighted magnetic resonance images. American journal of obstetrics and gynecology. 2007;196(2):184.e1-6.\u003c/li\u003e\n\u003cli\u003eSpies JB. Sustained relief of leiomyoma symptoms by using focused ultrasound surgery. Obstetrics and gynecology. 2007;110(6):1427-8; author reply 8-9.\u003c/li\u003e\n\u003cli\u003eStewart EA, Gostout B, Rabinovici J, Kim HS, Regan L, Tempany CM. Sustained relief of leiomyoma symptoms by using focused ultrasound surgery. Obstetrics and gynecology. 2007;110(2 Pt 1):279-87.\u003c/li\u003e\n\u003cli\u003eGomez E, Nguyen MT, Fursevich D, Macura K, Gupta A. MRI-based pictorial review of the FIGO classification system for uterine fibroids. Abdominal radiology (New York). 2021;46(5):2146-55.\u003c/li\u003e\n\u003cli\u003eChen J, Chen W, Zhang L, Li K, Peng S, He M, et al. Safety of ultrasound-guided ultrasound ablation for uterine fibroids and adenomyosis: A review of 9988 cases. Ultrasonics sonochemistry. 2015;27:671-6.\u003c/li\u003e\n\u003cli\u003eLi W, Yang Z, Gao B, Zou L, Xu D, Liu L, et al. Comparison of ultrasound-guided high-intensity focused ultrasound ablation and hysteroscopic myomectomy for submucosal fibroids: a retrospective study. International journal of hyperthermia : the official journal of European Society for Hyperthermic Oncology, North American Hyperthermia Group. 2021;38(1):1609-16.\u003c/li\u003e\n\u003cli\u003eLi W, Jiang Z, Deng X, Xu D. Long-term follow-up outcome and reintervention analysis of ultrasound-guided high intensity focused ultrasound treatment for uterine fibroids. International journal of hyperthermia : the official journal of European Society for Hyperthermic Oncology, North American Hyperthermia Group. 2020;37(1):1046-51.\u003c/li\u003e\n\u003cli\u003eXu F, Deng L, Zhang L, Hu H, Shi Q. The comparison of myomectomy, UAE and MRgFUS in the treatment of uterine fibroids: a meta analysis. International journal of hyperthermia : the official journal of European Society for Hyperthermic Oncology, North American Hyperthermia Group. 2021;38(2):24-9.\u003c/li\u003e\n\u003cli\u003eKeserci B, Duc NM. The role of T1 perfusion-based classification in magnetic resonance-guided high-intensity focused ultrasound ablation of uterine fibroids. European radiology. 2017;27(12):5299-308.\u003c/li\u003e\n\u003cli\u003eL\u0026eacute;n\u0026aacute;rd ZM, McDannold NJ, Fennessy FM, Stewart EA, Jolesz FA, Hynynen K, et al. Uterine leiomyomas: MR imaging-guided focused ultrasound surgery--imaging predictors of success. Radiology. 2008;249(1):187-94.\u003c/li\u003e\n\u003cli\u003ePark MJ, Kim YS, Rhim H, Lim HK. Safety and therapeutic efficacy of complete or near-complete ablation of symptomatic uterine fibroid tumors by MR imaging-guided high-intensity focused US therapy. Journal of vascular and interventional radiology : JVIR. 2014;25(2):231-9.\u003c/li\u003e\n\u003cli\u003eYoo EH, Lee PI, Huh CY, Kim DH, Lee BS, Lee JK, et al. Predictors of leiomyoma recurrence after laparoscopic myomectomy. Journal of minimally invasive gynecology. 2007;14(6):690-7.\u003c/li\u003e\n\u003cli\u003eLiu D, Zhang X, Gong X, Yang C, Zhang R, Chen W, et al. Learning Curve of USgHIFU Ablation for Uterine Fibroids: A Multi-Center Prospective Study. Journal of ultrasound in medicine : official journal of the American Institute of Ultrasound in Medicine. 2022;41(12):3051-9.\u003c/li\u003e\n\u003cli\u003eGong X, Zhang X, Liu D, Yang C, Zhang R, Xiao Z, et al. Physician Experience in Technical Success of Achieving NPVR \u0026ge; 80% of High-Intensity Focused Ultrasound Ablation for Uterine Fibroids: A Multicenter Study. Frontiers in medical technology. 2021;3:790956.\u003c/li\u003e\n\u003cli\u003eKeserci B, Duc NM. Magnetic resonance imaging features influencing high-intensity focused ultrasound ablation of adenomyosis with a nonperfused volume ratio of \u0026ge;90% as a measure of clinical treatment success: retrospective multivariate analysis. International journal of hyperthermia : the official journal of European Society for Hyperthermic Oncology, North American Hyperthermia Group. 2018;35(1):626-36.\u003c/li\u003e\n\u003cli\u003eKeserci B, Duc NM. Magnetic Resonance Imaging Parameters in Predicting the Treatment Outcome of High-intensity Focused Ultrasound Ablation of Uterine Fibroids With an Immediate Nonperfused Volume Ratio of at Least 90. Academic radiology. 2018;25(10):1257-69.\u003c/li\u003e\n\u003cli\u003eGong X, Liu D, Yang MJ, Zhang R, Chen WZ, Chen JY. Tolerance and efficacy of HIFU ablation for uterine fibroids NPVR \u0026ge; 90%: a nested case-control study. International journal of hyperthermia : the official journal of European Society for Hyperthermic Oncology, North American Hyperthermia Group. 2022;39(1):946-51.\u003c/li\u003e\n\u003cli\u003eRadosa MP, Owsianowski Z, Mothes A, Weisheit A, Vorwergk J, Asskaryar FA, et al. Long-term risk of fibroid recurrence after laparoscopic myomectomy. European journal of obstetrics, gynecology, and reproductive biology. 2014;180:35-9.\u003c/li\u003e\n\u003cli\u003eFlake GP, Andersen J, Dixon D. Etiology and pathogenesis of uterine leiomyomas: a review. Environmental health perspectives. 2003;111(8):1037-54.\u003c/li\u003e\n\u003cli\u003eZhao WP, Chen JY, Chen WZ. Effect of biological characteristics of different types of uterine fibroids, as assessed with T2-weighted magnetic resonance imaging, on ultrasound-guided high-intensity focused ultrasound ablation. Ultrasound in medicine \u0026amp; biology. 2015;41(2):423-31.\u003c/li\u003e\n\u003cli\u003eZhao WP, Zhang J, Han ZY, Yao JP, Zhou X, Liang P. A clinical investigation treating different types of fibroids identified by MRI-T2WI imaging with ultrasound guided high intensity focused ultrasound. Scientific reports. 2017;7(1):10812.\u003c/li\u003e\n\u003cli\u003eStewart EA, Gedroyc WM, Tempany CM, Quade BJ, Inbar Y, Ehrenstein T, et al. Focused ultrasound treatment of uterine fibroid tumors: safety and feasibility of a noninvasive thermoablative technique. American journal of obstetrics and gynecology. 2003;189(1):48-54.\u003c/li\u003e\n\u003cli\u003eYu O, Schulze-Rath R, Grafton J, Hansen K, Scholes D, Reed SD. Adenomyosis incidence, prevalence and treatment: United States population-based study 2006-2015. American journal of obstetrics and gynecology. 2020;223(1):94.e1-.e10.\u003c/li\u003e\n\u003c/ol\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":false,"isPdf":false,"isPdfUpToDate":true,"isWithdrawnOrRetracted":false,"journal":{"display":true,"email":"[email protected]","identity":"bmc-womens-health","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"bmwh","sideBox":"Learn more about [BMC Women's Health](http://bmcwomenshealth.biomedcentral.com/)","snPcode":"","submissionUrl":"https://www.editorialmanager.com/bmwh/default.aspx","title":"BMC Women's Health","twitterHandle":"","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"em","reportingPortfolio":"BMC Series","inReviewEnabled":true,"inReviewRevisionsEnabled":true},"keywords":"high intensity focused ultrasound (HIFU), uterine fibroids, non-perfusion volume ratio (NPVR), ablation, re-intervention","lastPublishedDoi":"10.21203/rs.3.rs-3817348/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-3817348/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003cp\u003e\u003cstrong\u003eObjective:\u0026nbsp;\u003c/strong\u003eTo report the long-term re-intervention of patients with uterine fibroids after\u0026nbsp;ultrasound-guided high-intensity focused ultrasound (USgHIFU) ablation, and analyse the influencing factors of re-intervention in group of NPVR ≥80%.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eMaterials and Methods:\u0026nbsp;\u003c/strong\u003eThe patients were divided into four groups according to different\u0026nbsp;non-perfusion volume ratio\u0026nbsp;(NPVR). Kaplan-Meier survival curve was used to analyse the long-term re-intervention in different NPVR groups, and Cox regression was used to analyse the influencing factors of re-intervention in the NPVR\u0026nbsp;≥\u0026nbsp;80% group.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eMain Results:\u0026nbsp;\u003c/strong\u003ePatients with single uterine fibroid who underwent USgHIFU from January 2012 to December 2019\u0026nbsp;in our hospital were enrolled.\u0026nbsp;A total of 1,257 patients were enrolled, of which 920 were successfully followed up. The median follow-up time was 88 months, and the median NPVR was 85.2%. The cumulative re-intervention rates of 1, 3, 5, 8 and 10 years after USgHIFU were 3.4%, 11.8%, 16.8%, 22.6% and 24.1%, respectively. The 10-year cumulative re-intervention rate was 37.3% in the group of NPVR \u0026lt;70%, 31.0% in the group of NPVR 70%–79%, 18.2% in the group of NPVR 80%–89% and 17.8% in the group of NPVR\u0026nbsp;≥90% (\u003cem\u003eP\u003c/em\u003e\u0026nbsp;\u0026lt;0.05). However, no difference was found between the group of NPVR 80%−89% and the group of NPVR\u0026nbsp;≥90% (\u003cem\u003eP\u003c/em\u003e=0.499). Age of patients and\u0026nbsp;signal intensity on T\u003csub\u003e2\u003c/sub\u003eWI\u0026nbsp;of\u0026nbsp;tumours\u0026nbsp;were independent risk factors for long-term re-intervention when NPVR was\u0026nbsp;≥80%. Lower age and higher\u0026nbsp;signal intensity on T\u003csub\u003e2\u003c/sub\u003eWI\u0026nbsp;corresponded to a\u0026nbsp;higher risk of re-intervention occurrence.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eConclusion:\u0026nbsp;\u003c/strong\u003eUSgHIFU, as an alternative treatment of uterine fibroids, has a reliable long-term efficiency. NPVR ≥80% can reduce the long-term re-intervention rates of patients, which can be used as a sign of technical success. However, an important step is to assess before ablation, considering both age of patients and fibroids of signal intensity on T\u003csub\u003e2\u003c/sub\u003eWI.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eTrial registration:\u0026nbsp;\u003c/strong\u003eThis retrospective study was approved by the ethics committee at our institution (Registration No. HF2023001; Date: 06/04/2023). The Chinese Clinical Trial Registry provided full approval for the study protocol (Registration No. CHiCTR2300074797; Date: 16/08/2023).\u003c/p\u003e","manuscriptTitle":"Achieving NPVR ≥ 80% as Technical Success of High-Intensity Focused Ultrasound Ablation for Uterine Fibroids: a cohort study","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2024-01-03 16:49:43","doi":"10.21203/rs.3.rs-3817348/v1","editorialEvents":[{"type":"communityComments","content":0},{"type":"decision","content":"Revision requested","date":"2024-04-01T11:02:55+00:00","index":"","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2024-02-13T00:49:43+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"29641d5b-adf0-4af1-a674-cdaf09c1910f","date":"2024-02-11T21:24:40+00:00","index":"hide","fulltext":""},{"type":"reviewersInvited","content":"","date":"2024-02-11T19:53:32+00:00","index":"","fulltext":""},{"type":"editorAssigned","content":"","date":"2024-02-11T19:50:51+00:00","index":"","fulltext":""},{"type":"editorInvited","content":"","date":"2024-01-16T15:47:28+00:00","index":"","fulltext":""},{"type":"checksComplete","content":"","date":"2023-12-29T03:12:43+00:00","index":"","fulltext":""},{"type":"submitted","content":"BMC Women's Health","date":"2023-12-28T15:10:07+00:00","index":"","fulltext":""}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"bmc-womens-health","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"bmwh","sideBox":"Learn more about [BMC Women's Health](http://bmcwomenshealth.biomedcentral.com/)","snPcode":"","submissionUrl":"https://www.editorialmanager.com/bmwh/default.aspx","title":"BMC Women's Health","twitterHandle":"","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"em","reportingPortfolio":"BMC Series","inReviewEnabled":true,"inReviewRevisionsEnabled":true}}],"origin":"","ownerIdentity":"de3f8f8f-557f-4707-8b76-5065370fc75d","owner":[],"postedDate":"January 3rd, 2024","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"under-review","subjectAreas":[],"tags":[],"updatedAt":"2024-04-15T08:57:36+00:00","versionOfRecord":[],"versionCreatedAt":"2024-01-03 16:49:43","video":"","vorDoi":"","vorDoiUrl":"","workflowStages":[]},"version":"v1","identity":"rs-3817348","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-3817348","identity":"rs-3817348","version":["v1"]},"buildId":"qtupq5eGEP_6zYnWcrvyt","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}