Prediction of Split Renal Function and Obstruction with MR Urography in Comparison with Dynamic Renal Scintigraphy

Prediction of Split Renal Function and Obstruction with MR Urography in Comparison with Dynamic Renal Scintigraphy | 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 Prediction of Split Renal Function and Obstruction with MR Urography in Comparison with Dynamic Renal Scintigraphy Seckin Cobanoglu, Hazal Karli, Emine Goknur Isik, Eda Cingoz, and 2 more This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-7255640/v1 This work is licensed under a CC BY 4.0 License Status: Published Journal Publication published 17 Feb, 2026 Read the published version in Pediatric Nephrology → Version 1 posted 5 You are reading this latest preprint version Abstract Purpose: MR urography examinations allow the assessment of kidney functions through recently developed image post-processing techniques, in addition to providing detailed visualization of urinary system anatomy. MR urography and MAG3 scintigraphy were compared in terms of functional evaluation. Methods: Dynamic contrast-enhanced MR urography images of 90 children who had previously undergone MAG3 scintigraphy examinations were evaluated. Morphological parameters, volumetric split renal functions (SRF) and renal transit times (RTT) were calculated from the dynamic MR urography phases using the CHOP-fMRU software for a total of 76 patients. Results were compared with the half-time (T1/2) and SRF values obtained from MAG3 scintigraphy. Student's t-test and Mann-Whitney U test were used to compare quantitative variables, and correlation analysis was performed. Results: The ages of the patients included in the study ranged from 1 to 216 months, with a mean age of 76.82 ± 62.59 months. Statistically significant positive correlations (r > 0.9, p =0.001) were found between SRFs of the right and left kidneys, measured by MR urography and scintigraphy. When the agreement between RTT and radionuclide half-life was evaluated, the sensitivity, specificity, positive and negative predictive values ​​of RTT for urinary obstruction were 65%, 83%, 90% and 53%, respectively. Conclusion: MR urography based SRF calculations could to be an invaluable tool in the assessment of separate renal functions. Its high positive predictive value in detecting obstruction rivals that of MAG3 scintigraphy. Despite the lack of extensive comparative data, the potential benefits of MR urography justify the need for further studies. MR urography MAG3 scintigraphy renal function children Figures Figure 1 Figure 2 Introduction Magnetic Resonance Urography (MRU) is of extremely important for detecting congenital malformations and acquired pathologies related to the kidneys and urinary tract in pediatric patients. Its noninvasive nature and lack of ionizing radiation make it a safe option, while its ability to provide detailed morphological and functional assessments facilitates comprehensive care [ 1 , 2 ]. Congenital malformations present a wide range of challenges, from harmless renal ectopia to potentially fatal bilateral renal agenesis. Rapid diagnosis and functional evaluation are crucial to determine appropriate treatment and achieve early functional recovery. This is particularly important because concomitant obstructive uropathy is a leading cause of renal failure in infancy [ 3 ]. By prioritizing early intervention, we can significantly improve outcomes and protect the health of our youngest patients. Ultrasonography (USG) and Computed Tomography (CT) are the primary radiological techniques for assessing the structure of the kidneys and urinary tract. However, for a more in-depth understanding of renal function, MRU stands out by providing critical functional data. Additionally, the voiding cystourethrogram (VCUG) not only provides vital anatomical details but also enables dynamic evaluation of the urinary system. Adopting these methods ensures a comprehensive assessment for optimal patient care. Integrating radionuclide scintigraphy with radiologic techniques in the evaluation of renal function, significantly improves diagnostic accuracy. Notably, dimercaptosuccinic acid (Tc-99m-DMSA), mercaptoacetyltriglycine (Tc-99m-MAG3), and diethylenetriaminepentaacetic acid (Tc-99m-DTPA) are vital tools in nuclear medicine, providing invaluable insights into renal health [ 4 ]. USG is a widely used tool in the evaluation of the urinary system in children, and performs effectively in identifying mildly and moderately dilated collecting systems. However, it falls short in evaluating nondilated or severely dilated collecting systems, highlighting the need for alternative diagnostic options to ensure comprehensive care and accurate assessment. It is not feasible to assess split renal function (SRF) using USG, because the accuracy of the results is significantly affected by the operator's expertise. MAG3 dynamic renal scintigraphy is considered the definitive gold standard for accurately assessing SRF and effectively identifying obstructions, making it an indispensable tool in modern renal diagnostics [ 5 ]. Although MAG3 scintigraphy can effectively assess SRF and the collecting system, radiation exposure and poor anatomical detail due to low spatial resolution are limiting factors for its use. MRU, due to its high spatial and contrast resolution, is an effective imaging technique for evaluating urinary system anatomy. In addition to assessing obstructive conditions through dynamic examinations, it also provides functional data through post-processing image analysis [ 6 ]. MRU is increasingly utilized, due to rapid imaging sequences that enable image acquisition during breath-hold periods and contrast medium-enhanced studies that include dynamic measurements [ 7 ]. MRU is a benefical imaging modality for the urinary tract in children, providing comprehensive anatomical and functional data while producing relatively high-quality images without the use of ionizing radiation. The literature reveals a remarkable paucity of comparative and quantitative functional studies that directly assess MAG3 scintigraphy versus contrast-enhanced MRU. This lack of research contributes to a limited understanding of how MRU performs compared to MAG3 scintigraphy, and highlights the need for further investigation in this area [ 8 – 10 ]. This study aims to significantly advance our knowledge of SRF by comparing MRU and MAG3 scintigraphy. Moreover, it aims to provide valuable insights into obstruction prediction. Material and Method In the current study, we evaluated dynamic MRU and dynamic renal scintigraphy using MAG3 in 90 patients. These patients were followed for congenital urinary system anomalies at our hospital between 2006 and 2021. None of the patients had a history of urinary tract infection or surgical intervention within the previous six months. The evaluation was conducted retrospectively by a nuclear medicine specialist and two radiologists, one of whom is board-certified. Informed consent was waived due to the retrospective nature of the study. The study was approved by the local Ethics Committee on October 12, 2021 (File Number: 22). MRU examinations were performed in the supine position using a 1.5 Tesla device (Magnetom Symphony and Magnetom Aera, Siemens Healthcare). A head coil or a phased array receiver coil was used, depending on the patient's body size. After localizer images were obtained in all three planes, coronal and axial plane images were obtained using a HASTE (single-shot fast spin echo) sequence. Imaging began at the superior aspect of the diaphragm and continued down to the bladder. T1- and T2-weighted images were obtained, and the static examination was completed with heavy T2 sequences in the coronal plane. A T1-weighted 3D gradient echo sequence was used for dynamic analysis. Our clinic's hydration protocol for MRU examination includes the administration of 20 mL/kg of saline 30 minutes prior to the study, followed by 10 mL/kg during the examination. After ensuring that patients were well-hydrated and had satisfactory urine output, intravenous furosemide was administered at a dose of 0.3 mg/kg to facilitate visualization of the collecting system. Following initial images obtained without contrast material, a contrast agent (gadobutrol and gadoterate meglumin) was administered as an IV bolus at a dose of 0.1 mmol/kg. Dynamic examinations were then completed by obtaining additional images. The diuretic renal scintigraphy utilized Tc99m-MAG3, which is the preferred radioisotope for the pediatric population. Prior to the procedure, patients received oral or intravenous hydration, depending on their age. Posterior dynamic images were captured after injecting 3.7 MBq/kg of the radionuclide agent and 1 mg/kg of furosemide (with a maximum dose of 20 mg). A nuclear medicine specialist evaluated the images and determined Tmax, T1/2, and SRF values. Urinary tract morphology was assessed using various parameters during MRU examinations, including parenchyma thickness, anterior-posterior diameter of the renal pelvis, and kidney dimensions obtained from conventional sequences. Temporal and quantitative data regarding SRF and renal transit time (RTT) were gathered using the semi-automated MR urography software developed by the Children's Hospital of Philadelphia (CHOP). SRFs obtained by MRU were compared with the results of MAG3 scintigraphy, the standard method used before MRU examinations. To assess urinary system obstruction in the same patient group, we evaluated T1/2, which represents the time required for renal activity to decrease to 50% of its maximum value calculated by MAG3 scintigraphy, and RTT, which represents the time required for the contrast agent to be visualized in the ureteral segment below the lower pole of the related kidney, observed in the arterial phase of the renal cortex on dynamic post-contrast imaging [ 11 ]. Considering the RTT, urinary tract obstruction detection was classified as normal (RTT ≤ 245 sec), suspicious (245 490 sec) as given in the latest study [ 12 ]. In scintigraphy, which is the reference method for demonstrating obstruction, cases with T1/2 time greater than 20 minutes were selected, and the sensitivity, specificity, and positive and negative predictive values of RTT in the assessment of urinary tract obstruction ​​were analyzed. Statistical analyses were performed using the NCSS (Number Cruncher Statistical System) program. Study data were evaluated using descriptive statistical methods (mean, standard deviation, median, minimum, and maximum). The Shapiro-Wilk test and graphical analyses were used to ensure compliance of quantitative data with normal distribution. The Student-t test was used to compare quantitative variables with normal distribution between two groups, and the Mann-Whitney U test was used to compare quantitative variables with non-normal distribution. McNemar goodness of fit test and diagnostic screening tests were used to compare qualitative data. Pearson correlation analysis was used to evaluate relationships between quantitative variables. Statistical significance was accepted as p < 0.05. Results A total of 90 patients; 43 females (48%), and 47 males (52%), participated in the study. The ages of the cases ranged from 1 to 216 months. The mean and standard deviation (Mean ± SD) for all the participants were 76.82 ± 62.59 months. The diagnoses made to the patients as a result of clinical evaluation and MR imaging were determined as; ureteropelvic junction obstruction (n:37), double collecting system (n:15), unilateral renal agenesis (n:6), vesicoureteral reflux (n:9), ureterovesical junction obstruction (n:6), congenital megaureter (n:4), multicystic dysplastic kidney (n:3), horseshoe kidney (n:2), ureterocele (n:2), posterior urethral valve (n:1), renal hypoplasia (n:3), bladder exstrophy (n:1), and neurogenic bladder (n:1). The morphological evaluation results regarding the size, parenchymal thickness, renal pelvis and ureter diameter, and renal volume in each ureteropelvic unit are given in Table 1 . Table 1 Evaluation of Morphological Parameters in Ureteropelvic Units Left (n:95) Right (n:93) p Size (mm) Mean ± SD 79.29 ± 29.81 79.92 ± 25.85 a 0.876 Median(Min-Max) 80.4 (22–151) 79.9 (17–156) Parenchymal Thickness (mm) Mean ± SD 9.96 ± 9.46 10.79 ± 9.42 b 0.308 Median(Min-Max) 8.4 (0–87) 9.7 (0–85) AP Diameter of Renal Pelvis (mm) Mean ± SD 13.55 ± 12.84 10.98 ± 9.25 b 0.459 Median(Min-Max) 7.9 (0-52.2) 8.7 (0-51.8) Ureter Diameter (mm) Mean ± SD 5.83 ± 5.42 4.32 ± 4.56 b 0.012* Median(Min-Max) 3.2 (0-28.8) 2.5 (1-23.7) Volume (mL) Mean ± SD 51.00 ± 43.83 54.42 ± 34.98 b 0.117 Median(Min-Max) 39 (2-265) 47 (0-171) a Student-t Test , b Mann Whitney U Test, *p < 0.05 was depicted as statistically significant. When a total of 188 ureteropelvic units; (93 right, 95 left), were examined, dilatation was detected in 95 (50.5%) of the units, while pelvicaliectasis was not observed in 93 (49.5%). Of the dilated units, 45 (47%) were located on the right side, and 50 (53%) were located on the left side. When urinary system obstructions were evaluated, 46.6% of the obstructions were detected in the right collecting system and 53.4% in the left collecting system. No statistically significant differences were detected between renal pelvis measurements, parenchymal thickness, AP diameter, and right and left kidney volumes (p > 0.05). A weak positive correlation between the AP diameter of renal pelvis and kidney size was found to be statistically significant (r = 0.345; p = 0.001). A negative correlation between the AP diameter of the renal pelvis and parenchymal thickness of the cases included in the study was found to be statistically significant (r=-0.323; p = 0.001). Patients with unilateral renal agenesis (6 patients), multicystic dysplastic kidney (3 patients), and 5 patients in whom the renal parenchymal segmentation could not be performed due to motion artifact in dynamic studies were excluded from functional evaluation on dynamic MRU sequences. Since there was no MAG3 scintigraphy data divided into upper and lower systems for comparison in cases with double collecting systems, each kidney was evaluated as a ureteropelvic unit, regardless of the number of collecting systems. A total of 152 kidneys of the remaining 76 patients, 76 right and 76 left, were quantitatively evaluated on dynamic images. The mean time interval between scintigraphy and MRU examinations was 41 ± 29 days. The mean right SRF measurements obtained by scintigraphy for the individuals participating in the study were 52.58 ± 17.84%, and the mean left SRF measurements were 47.42 ± 17.84%. The mean right SRF measurements obtained with functional MRU were 53.03 ± 14.46%, and the mean left SRF measurements were 46.87 ± 14.50%. Very strong positive correlations were obtained between dynamic renal scintigraphy and dynamic MRU-based right (r = 0.937; p = 0.001) and left (r = 0.936; p = 0.001) SRF measurements (Table 2 , Fig. 1 ). Table 2 Distribution of Dynamic Renal Scintigraphy and Dynamic MR Urography SRF Measurements p r* Right SRF Scintigraphy Mean ± SD 52.58 ± 17.84 0.001 0.937 Median(Min-Max) 52.5 (0-100) SRF MRU Mean ± SD 53.03 ± 14.46 Median(Min-Max) 52.5 (12–87) Left SRF Scintigraphy Mean ± SD 47.42 ± 17.84 0.001 0.936 Median(Min-Max) 47.5 (0-100) SRF MRU Mean ± SD 46.87 ± 14.50 Median(Min-Max) 47.5 (13–88) *r = Pearson Correlation Coefficient When ipsilateral ureteropelvic units were grouped according to the presence of obstruction based on scintigraphic findings, SRF values of obstructed units were found to be significantly lower than those of non-obstructed units for both the right and left side (Table 3 ) . Table 3 Comaprison of Dynamic Renal Scintigraphy and Dynamic MR Urography based SRF Measurements According to Presence of Obstruction With Obstruction Without Obstruction p Right SRF Scintigraphy Mean ± SD 51.75 ± 7.44 Mean ± SD 61.14 ± 15.5 0.04 SRF MRU Mean ± SD 52.05 ± 8.3 Mean ± SD 59.01 ± 14.35 0.045 Left SRF Scintigraphy Mean ± SD 42.42 ± 17.84 Mean ± SD 53.4 ± 12.08 0.035 SRF MRU Mean ± SD 43.01 ± 11.4 Mean ± SD 53.02 ± 13.17 0.037 Among the right kidneys, 48 cases with urinary obstruction were found according to the T1/2 by scintigraphy. Thirty-one of these cases were found to be positive, while 17 were found to be negative in terms of obstruction by RTT. Accordingly, the sensitivity, specificity, positive and negative predictive values, and accuracy of RTT were found to be 64.58%, 85.71%, 88.57%, 58.54%, and 72.37%, respectively (Table 4 ). Among the left kidneys, 55 cases with urinary obstruction were found according to the T1/2 by scintigraphy. Thirty-six of these cases were found to be positive by RTT. In 17 cases both RTT and T1/2 time excluded obstruction. Accordingly, the sensitivity, specificity, positive and negative predictive values, and accuracy of RTT were 65.45%, 80.95%, 90%, 47.22%, and 69.74%, respectively ( Table 5 , Fig. 2 ) . Among all the kidneys, the sensitivity, specificity, positive and negative predictive values of RTT for urinary obstruction were depicted as 65%, 83%, 90%, and 53%, respectively. Table 4 Evaluation of T1/2 and RTT Compliance for the Right Urinary System Right Side T1/2 (scintigraphy(min)) Obstruction (+) Obstruction (-) Total N (%) n(%) n(%) p RTT(MRU(min)) Obstruction (+) 31 (40.8) 4 (5.3) 35 (46.1) 0.007** Obstruction (-) 17 (22.4) 24 (31.6) 41 (53.9) Total n (%) 48 (63.2) 28 (36.8) 76 (100.0) Diagnostic Test Results (%) Sensitivity 64.58 Specificity 85.71 Positive Predictive Value 88.57 Negative Predictive Value 58.54 Diagnostic Accuracy 72.37 McNemar Test **p < 0.01 Table 5 Evaluation of T1/2 and RTT Compliance for the Left Urinary System Left Side T1/2 (scintigraphy (min) ) Obstruction (+) Obstruction (-) Total n (%) n (%) N (%) p RTT(MRU(min)) Obstruction (+) 36 (47.4) 4 (5.3) 40 (52.6) 0.003** Obstruction (-) 19 (25.0) 17 (22.4) 36 (47.4) Total 55 (72.4) 21 (27.6) 76 (100.0) Diagnostic Test Results (%) Sensitivity 65.45 Specificity 80.95 Positive Predictive Value 90.00 Negative Predictive Value 47.22 Diagnostic Accuracy 69.74 McNemar Test **p < 0.01 Discussion In our study, volumetric SRF was calculated by converting the enhanced renal parenchymal volume into percentages, with the assumption that the right and left kidneys account for 100% of the renal function via the software and compared with MAG3 scintigraphy results, currently considered the reference method for renal functions. SRF obtained from MRU examinations of the right and left kidneys showed highly significant positive correlations with MAG3 scintigraphy results. In addition, we achieved acceptable and promising diagnostic accuracy of MRU in the diagnosis of urinary obstruction at the level of pelvicalyceal system. SRF represents the function of a kidney relative to total kidney function and is an important measure in renal health assessment. Renal scintigraphy is the standard method for determining SRF, and MAG3 scintigraphy is currently considered the gold standard due to its accuracy in detecting SRF [ 13 ]. This method not only detects SRF but also evaluates urinary tract obstructions. When used in conjunction with USG, which provides detailed anatomical information about the kidneys and collecting system, these techniques provide essential complementary information [ 14 ]. However, it is important to consider the drawbacks of this combination such as exposure to ionizing radiation during scintigraphy, and the operator-dependent nature of USG especially when it struggles to visualize both non-dilated and extremely dilated collecting systems. This limitation highlights the urgent need for alternative imaging modalities that enhance diagnostic accuracy and patient safety. Recently, Computed Tomography Urography (CTU) and functional MRU have been proposed as alternatives to conventional methods for estimating SRF [ 14 ]. CTU-based estimation of SRF relies on the amount of contrast medium excreted by the kidneys. Shi et al. demonstrated that combining CTU images of the nephrographic phase with serum creatinine levels successfully determined SRF [ 15 ]. You et al. revealed a good correlation between the scintigraphy and CTU in terms of the determination of SRF enabling the evaluation of renal function without additional radiation dose [ 16 ]. A comparison of CTU and routine reference scintigraphy to estimete SRF was evaluated in a prospective study conducted by Yuan et al. The findings were satisfactory and resulted in accurate measurements [ 17 ]. Nonetheless, CTU employs ionizing radiation, and there are contraindications to the use of iodine-based contrast medium in certain patient groups, necessitating the consideration of alternative modalities. Recent studies have proposed the use of functional MRU as an alternative to conventional studies for evaluating SRF in patients with obstructive uropathy [ 8 , 9 , 14 , 18 ]. Functional MRU is rapidly becoming a vital tool in daily medical practice, as it allows for precise determination of morphological details. Its advanced capability to distinguish the signal intensities of soft tissue components provides exceptional soft tissue contrast, making it an invaluable asset for accurate diagnosis and treatment planning [ 19 , 20 ]. This approach is highly effective in the management of complex congenital anomalies of the kidney and urinary tract (CAKUT) and offers the significant advantage of completely eliminating exposure to ionizing radiation [ 5 ]. Studies comparing scintigraphic methods and MRU in evaluating SRF have demonstrated a significant correlation between the two approaches. Furthermore, MRU stands out by providing precise measurements of the contrast enhanced renal parenchymal volume, making it a valuable tool in clinical practice [ 10 , 21 ]. Although MRU has a significant role in the assessment of SRF, due to the lack of comprehensive studies comparing the two techniques in the current literature, scintigraphic studies are still considered the reference method for the evaluation of obstructive uropathy as well as for guiding treatment decisions [ 5 ]. Damasio et al. found no significant difference in the drainage curves between MRU and scintigraphic evaluations in patients with CAKUT [ 5 ]. Rodigas et al. demonstrated that functional MRU offers significant diagnostic advantages, making it an essential complementary examination for challenging cases [ 14 ]. Claudon et al. demonstrated that MRU is as effective as scintigraphy for moderately dilated collecting systems. Therefore, adopting MRU as a substitute for scintigraphy is not only advisable but also beneficial for enhancing diagnostic accuracy and efficiency [ 21 ]. SRF measurements have been obtained via signal-intensity curves in dynamic contrast-enhanced MR nephropraphy, 3D gradient echo sequence with compressed-sensing and paralel imaging reconstruction by considering and grouping renal functions, non-contrast MRU derived texture parameters in comparison with scintigraphy, and integrated diffusion tensor imaging and renal parenchymal volume compared with scintigraphy [ 22 – 25 ]. Although some SRF results have been evaluated in comparison with scintigraphy, our study differs due to the patient group and methodologies, and direct comparisons can not be made. In a study closely aligning with our findings, volumetric SRF calculated with CHOP-fMRU software demonstrated a significant correlation with MAG3 scintigraphy data. This research, which included 58 patients, mostly diagnosed with ureteropelvic junction (UPJ) obstruction (57%), highlights the reliability of these imaging techniques [ 26 ]. In a recent investigation by Jurkiewicz et al. on 46 pediatric patients, MRU-based SRF was compared with renal scintigraphy utilizing 99mTc-ethylenedicysteine (99mTc-EC). A strong agreement observed between these two methods further strenghtens the reliability of our results and supports their use in clinical practice [ 27 ]. Additionally, a recent study comparing MRU with MAG3 scintigraphy to assess ureteropelvic junction obstruction demonstrated impressive correlation coefficients regarding relative renal functions, highlighting the reliability of MRU as a diagnostic tool in this context [ 28 ]. Functional analysis data obtained from the two software programs, “CHOP-fMRU” and “Image J,” were meticulously compared with each other and with findings obtained from the 99mTc-Diethylenetriamine pentaacetate (DTPA) dynamic renal scintigraphy [ 29 ]. The results indicated that there were no statistically significant differences between caliceal and renal transit times, renal parenchymal volumes, and volumetric SRF when CHOP-fMRU and Image J were compared (p > 0.05). Furthermore, the volumetric SRF values obtained from both CHOP-fMRU and Image J closely overlapped with the values obtained from the 99mTc-DTPA study, supporting the reliability of these imaging techniques. There is a distinct lack of quantitative and semiquantitative studies examining urinary obstruction using MRU in children. Utilizing parameters such as calyceal transit time, RTT, and mean transit time is crucial for a comprehensive quantitative assessment. Further research in this area could significantly improve our knowledge and management of urinary obstruction in pediatric patients. In a recent study, the RTT values in normal kidneys, were found to range from 2.37 to 6.52 minutes in those with a ½ Tmax of less than 10 minutes as measured by MAG-3 scintigraphy. In contrast, kidneys exhibiting moderate uropathy, with a ½ Tmax value between 10 and 15 minutes, had a RTT range of 4.13 to 12.32 minutes [ 30 ]. In a study comparing UPJ obstruction using MRU and MAG3 scintigraphy, MAG3 scintigraphy was considered the gold standard for obstruction when a half-life (T1/2) of 20 minutes or greater was established. A study using a cut-off value of 6 minutes for RTT on MRU revealed a sensitivity of 61.9%, a specificity of 94.1%, and an impressive area under the curve value of 0.8271. These results highlight the effectiveness of MRU in evaluating UPJ stenosis alongside MAG3 scintigraphy [ 31 ]. The remarkable correlation between the RTT values and T1/2 underscores its reliability, resulting in an impressive sensitivity of 100% and a specificity of 81.6%, making it a valuable tool in the diagnosis of urinary tract disorders [ 14 ]. Jones et al. reported that the RTT obtained from MR urography examination and the half-life of renal signal decay obtained from dynamic renal scintigraphy were equally effective in predicting obstruction [ 12 ]. In our study, we used the same classification to demonstrate obstruction by calculating the RTT via the software for a total of 152 kidneys in 76 patients. Comparing our data with scintigraphy examinations with T1/2 periods longer than 20 minutes, which indicate obstruction, we identified 67 true positives, 8 false positives, 41 true negatives, and 36 false negatives in 152 kidneys. The negative predictive value was found to be 53%. All of the false-negative cases in our study fell within the suspicious (> 245 ≤ 490 sec) timeframe according to the classification. In our study, the specificity value for RTT was similar to the results of Rodigas at al. but lower than the results of Viteri at.al. [ 12 , 31 ]. For diagnosis of obstructive uropathy, the area under the curve for RTT was found to be 0.9, while the diagnostic accuracy was 0.69–0.72. While RTT is increasingly recognized as a valuable quantitative parameter, the literature remains insufficient. There is a distinct lack of studies comparing scintigraphy with parameters such as mean transit time and calisial transit time. Due to the lack of comparative publications evaluating these metrics and the lack of sufficient data on RTT values, we chose to focus on RTT in our preliminary study for prediction of obstruction. Conducting further comparative studies that include quantitative parameters is crucial for advancing our understanding. Furthermore, emerging data on the SRF parameter have shown promising correlation with scintigraphy. The location and severity of obstruction are complex and diverse, further highlighting the need for comprehensive studies that account for these differences and effectively categorize them. Our study has some limitations. First, bladder catheterization was not performed immediately before the MRU. Although we advised toilet-trained children to urinate before the dynamic examination, a full bladder could decrease urine flow. This may have resulted in reduced excretion and could mimic an obstruction. In addition, because the MRU and scintigraphy examinations were evaluated within the scope of a retrospective study, the examinations were not performed simultaneously. Furthermore, we did not precisely categorize the patient group according to the degree and level of obstruction and dilatation. Multiple subdivisions requires a large sample size. To significantly enrich the literature, future research should include several subgroups along with preoperative and postoperative comparisons, as well as the analysis of quantitative parameters along with scintigraphy. This would provide a more comprehensive understanding of the outcomes. Conclusion There is a significant positive correlation between SRF values obtained via MRU and MAG3 scintigraphy. RTT values obtained from MRU offer valuable diagnostic accuracy for prediction of urinary obstruction when compared with T1/2 obtained from MAG3 scintigraphy. Thus, dynamic contrast enhanced MRU-based quantitative results are helpful in determining functional status of kidney. Declarations Ethical approval : The study was approved by the Ethics Committee of the Istanbul Faculty of Medicine (Date:10/12/2021, File Number: 22) in compliance with the Helsinki Declaration. Competing Interests: The authors have no relevant financial or non-financial interests to disclose. Funding: The authors have declared that the study was conducted without the receipt of any financial support. Availability of Data and materials: Data generated or analyzed during the current study are available from the corresponding author upon reasonable request. References Dickerson EC, Dillman JR, Smith EA, DiPietro MA, Lebowitz RL, Darge K (2015) Pediatric MR Urography: Indications, Techniques, and Approach to Review. Radiographics 35(4):1208–1230 Otero HJ, Elsingergy MM, Back SJ (2022) Magnetic resonance urography: a practical approach to preparation, protocol and interpretation. Pediatr Radiol McLean RH, Gearhart JP, Jeffs R (1988) Neonatal obstructive uropathy. Pediatr Nephrol 2(1):48–55 Mendichovszky I, Solar BT, Smeulders N, Easty M, Biassoni L (2017) Nuclear Medicine in Pediatric Nephro-Urology: An Overview. Semin Nucl Med 2017;47(3):204 – 28 Damasio MB, Bodria M, Dolores M, Durand E, Sertorio F, Wong MCY et al (2019) Comparative Study Between Functional MR Urography and Renal Scintigraphy to Evaluate Drainage Curves and Split Renal Function in Children With Congenital Anomalies of Kidney and Urinary Tract (CAKUT). Front Pediatr 7:527 Khrichenko D, Darge K (2010) Functional analysis in MR urography - made simple. Pediatr Radiol 40(2):182–199 Katzberg RW, Buonocore MH, Ivanovic M, Pellot-Barakat C, Ryan JM, Whang K et al (2001) Functional, dynamic, and anatomic MR urography: feasibility and preliminary findings. Acad Radiol 8(11):1083–1099 Vivier PH, Dolores M, Taylor M, Elbaz F, Liard A, Dacher JN (2010) MR urography in children. Part 1: how we do the F0 technique. Pediatr Radiol 40(5):732–738 Vivier PH, Dolores M, Taylor M, Dacher JN (2010) MR urography in children. Part 2: how to use ImageJ MR urography processing software. Pediatr Radiol 40(5):739–746 Boss A, Martirosian P, Fuchs J, Obermayer F, Tsiflikas I, Schick F et al (2014) Dynamic MR urography in children with uropathic disease with a combined 2D and 3D acquisition protocol–comparison with MAG3 scintigraphy. Br J Radiol 87(1044):20140426 Grattan-Smith JD, Chow J, Kurugol S, Jones RA (2022) Quantitative renal magnetic resonance imaging: magnetic resonance urography. Pediatr Radiol 52(2):228–248 Jones RA, Perez-Brayfield MR, Kirsch AJ, Grattan-Smith JD (2004) Renal transit time with MR urography in children. Radiology 233(1):41–50 Prigent A, Cosgriff P, Gates GF, Granerus G, Fine EJ, Itoh K et al (1999) Consensus report on quality control of quantitative measurements of renal function obtained from the renogram: International Consensus Committee from the Scientific Committee of Radionuclides in Nephrourology. Semin Nucl Med 29(2):146–159 Rodigas J, Kirsch H, John U, Seifert P, Winkens T, Stenzel M et al (2018) Static and Functional MR Urography to Assess Congenital Anomalies of the Kidney and Urinary Tract in Infants and Children: Comparison With MAG3 Renal Scintigraphy and Sonography. AJR Am J Roentgenol 211(1):193–203 Shi W, Liang X, Wu N, Zhang H, Yuan X, Tan Y (2020) Assessment of Split Renal Function Using a Combination of Contrast-Enhanced CT and Serum Creatinine Values for Glomerular Filtration Rate Estimation. AJR Am J Roentgenol 215(1):142–147 You S, Ma X, Zhang C, Li Q, Shi W, Zhang J et al (2018) Determination of single-kidney glomerular filtration rate (GFR) with CT urography versus renal dynamic imaging Gates method. Eur Radiol 28(3):1077–1084 Yuan X, Zhang J, Tang K, Quan C, Tian Y, Li H et al (2017) Determination of Glomerular Filtration Rate with CT Measurement of Renal Clearance of Iodinated Contrast Material versus (99m)Tc-DTPA Dynamic Imaging Gates Method: A Validation Study in Asymmetrical Renal Disease. Radiology 282(2):552–560 Riccabona M, Avni FE, Dacher JN, Damasio MB, Darge K, Lobo ML et al (2010) ESPR uroradiology task force and ESUR paediatric working group: imaging and procedural recommendations in paediatric uroradiology, part III. Minutes of the ESPR uroradiology task force minisymposium on intravenous urography, uro-CT and MR-urography in childhood. Pediatr Radiol 40(7):1315-20 Arlen AM, Kirsch AJ, Cuda SP, Little SB, Jones RA, Grattan-Smith JD et al (2014) Magnetic resonance urography for diagnosis of pediatric ureteral stricture. J Pediatr Urol 2014;10(5):792-8 Dillman JR, Trout AT, Smith EA (2016) MR urography in children and adolescents: techniques and clinical applications. Abdom Radiol (NY) 41(6):1007–1019 Claudon M, Durand E, Grenier N, Prigent A, Balvay D, Chaumet-Riffaud P et al (2014) Chronic urinary obstruction: evaluation of dynamic contrast-enhanced MR urography for measurement of split renal function. Radiology 273(3):801–812 Krumm P, Hupka T, Haußmann F, Dittmann H, Mühlbacher T, Nadalin S et al (2021) Contrast-enhanced MRI for simultaneous evaluation of renal morphology and split renal function in living kidney donor candidates. Eur J Radiol 142:109864 Wang Y, He C, Lai S, Xu X, Cai X, Li J et al (2024) Integrated Diffusion Tensor Imaging and Renal Parenchymal Volume for Early Detection and Grading of Split Renal Functional Impairment in Lupus Nephritis. Acad Radiol 31(7):2827–2837 He K, Wan D, Li S, Yuan G, Gao M, Han Y et al (2024) Non-contrast-enhanced magnetic resonance urography for measuring split kidney function in pediatric patients with hydronephrosis: comparison with renal scintigraphy. Pediatr Nephrol 39(5):1447–1457 Schulze-Zachau V, Winkel DJ, Kaul F, Demerath T, Potthast S, Heye TJ et al (2023) Estimation of differential renal function on routine abdominal imaging employing compressed-sensed contrast-enhanced MR: a feasibility study referenced against dynamic renal scintigraphy in patients with deteriorating renal retention parameters. Abdom Radiol (NY) 48(4):1329–1339 Dzananovic A, Begic A, Pokrajac D (2019) Evaluation of Congenital Hydronephrosis with Static and Dynamic Magnetic Resonance Urography in Comparation to Dynamic Renal Scintigraphy. Acta Inf Med 27(3):181–185 Gołuch M, Pytlewska A, Sarnecki J, Chodnicka P, Śliwińska A, Obrycki Ł et al (2024) Evaluation of differential renal function in children – a comparative study between magnetic resonance urography and dynamic renal scintigraphy. BMC Pediatr 24(1):213 Al-Shaqsi Y, Peycelon M, Paye-Jaouen A, Carricaburu E, Tanase A, Grapin-Dagorno C et al (2024) Evaluating pediatric ureteropelvic junction obstruction: Dynamic magnetic resonance urography vs renal scintigraphy 99m-technetium mercaptoacetyltriglycine. World J Radiol 16(3):49–57 Hadjidekov G, Hadjidekova S, Tonchev Z, Bakalova R, Aoki I (2011) Assessing renal function in children with hydronephrosis - additional feature of MR urography. Radiol Oncol 45(4):248–258 Świȩtoń D, Grzywińska M, Czarniak P, Gołȩbiewski A, Durawa A, Teodorczyk J et al (2022) The Emerging Role of MR Urography in Imaging Megaureters in Children. Front Pediatr 10:839128 Viteri B, Calle-Toro JS, Ballester L, Darge K, Furth S, Khrichenko D et al (2021) Potential benefits of functional magnetic resonance urography (fMRU) over MAG3 renal scan in children with obstructive uropathy. J Pediatr Urol 17(5):659. e1-.e7 Supplementary Files renamedd5f99.pptx Cite Share Download PDF Status: Published Journal Publication published 17 Feb, 2026 Read the published version in Pediatric Nephrology → Version 1 posted Editorial decision: Major Revisions Needed 21 Sep, 2025 Reviewers agreed at journal 01 Sep, 2025 Reviewers invited by journal 31 Jul, 2025 Editor assigned by journal 31 Jul, 2025 First submitted to journal 30 Jul, 2025 You are reading this latest preprint version Research Square lets you share your work early, gain feedback from the community, and start making changes to your manuscript prior to peer review in a journal. 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-7255640","acceptedTermsAndConditions":true,"allowDirectSubmit":false,"archivedVersions":[],"articleType":"Research Article","associatedPublications":[],"authors":[{"id":493908557,"identity":"4869eeab-ff0d-42fa-90b6-f541058abe06","order_by":0,"name":"Seckin Cobanoglu","email":"","orcid":"","institution":"Istanbul Universitesi","correspondingAuthor":false,"prefix":"","firstName":"Seckin","middleName":"","lastName":"Cobanoglu","suffix":""},{"id":493908558,"identity":"4e90f3c9-4337-447a-ab4f-47cf36c44db9","order_by":1,"name":"Hazal Karli","email":"","orcid":"","institution":"Istanbul Universitesi","correspondingAuthor":false,"prefix":"","firstName":"Hazal","middleName":"","lastName":"Karli","suffix":""},{"id":493908559,"identity":"cba97135-1362-460c-a1c5-df7c197793ef","order_by":2,"name":"Emine Goknur Isik","email":"","orcid":"","institution":"Istanbul Universitesi","correspondingAuthor":false,"prefix":"","firstName":"Emine","middleName":"Goknur","lastName":"Isik","suffix":""},{"id":493908560,"identity":"ee0bb549-1a32-4c45-8f30-a1e964cc0d8f","order_by":3,"name":"Eda Cingoz","email":"","orcid":"","institution":"Istanbul Universitesi","correspondingAuthor":false,"prefix":"","firstName":"Eda","middleName":"","lastName":"Cingoz","suffix":""},{"id":493908561,"identity":"528b7903-1d93-48e3-a7df-5fe7c4d455a7","order_by":4,"name":"Ravza Yilmaz","email":"","orcid":"","institution":"Istanbul Universitesi","correspondingAuthor":false,"prefix":"","firstName":"Ravza","middleName":"","lastName":"Yilmaz","suffix":""},{"id":493908562,"identity":"1c12e7cd-2f7b-4d0a-9b7c-00ef742e8228","order_by":5,"name":"zuhal bayramoglu","email":"data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAZAAAAAyAQMAAABI0h/eAAAABlBMVEX///8AAABVwtN+AAAACXBIWXMAAA7EAAAOxAGVKw4bAAAAzElEQVRIiWNgGAWjYBACNgh1gIGPvYGBmTQtbDwHiNTCANcikUCkFj7p5ocPf7bdkWeTfGP4uaDChoG/vTsBv8NkjhkbSLY9M2yTzjGWnnEmjUHizNkN+LVI5LBJGLYdZgRqMZDmbTvMYCCRS1AL+4/EtsP2bZJnjH8Tq4WN4WDb4cQ2CR4zYm1JM5ZsOHc4uY0nrcya50waD0G/yM9IfvjxR9lh2372w5tv81TYyPG39+LXggQ4DEAkD7HKQYD9ASmqR8EoGAWjYAQBAMn8QOAQThBQAAAAAElFTkSuQmCC","orcid":"","institution":"Istanbul University Istanbul Faculty of Medicine: Istanbul Universitesi Istanbul Tip Fakultesi","correspondingAuthor":true,"prefix":"","firstName":"zuhal","middleName":"","lastName":"bayramoglu","suffix":""}],"badges":[],"createdAt":"2025-07-30 18:27:08","currentVersionCode":1,"declarations":"","doi":"10.21203/rs.3.rs-7255640/v1","doiUrl":"https://doi.org/10.21203/rs.3.rs-7255640/v1","draftVersion":[],"editorialEvents":[{"content":"https://doi.org/10.1007/s00467-026-07211-y","type":"published","date":"2026-02-17T15:58:24+00:00"}],"editorialNote":"","failedWorkflow":false,"files":[{"id":88422428,"identity":"5b9df65f-b3aa-4486-927e-ba1392725fe9","added_by":"auto","created_at":"2025-08-06 09:36:16","extension":"png","order_by":1,"title":"Figure 1","display":"","copyAsset":false,"role":"figure","size":34196,"visible":true,"origin":"","legend":"\u003cp\u003eDistribution of the relationship between SRF measurements obtained by scintigraphy and MRU. Very strong positive correlations were found between the SRF measurements obtained by dynamic renal scintigraphy and dynamic MR urography (r=0.9; p=0.001).\u003c/p\u003e","description":"","filename":"1.png","url":"https://assets-eu.researchsquare.com/files/rs-7255640/v1/eeb340ca3a997686a2830324.png"},{"id":88422431,"identity":"8a0a70b1-d3e4-42cb-91cf-e8143c8ea4c8","added_by":"auto","created_at":"2025-08-06 09:36:16","extension":"png","order_by":2,"title":"Figure 2","display":"","copyAsset":false,"role":"figure","size":258060,"visible":true,"origin":"","legend":"\u003cp\u003eFunctional MR urography imaging of a 9-month-old female patient followed for ureteropelvic junction obstruction. A-B. Dilated renal pelvis and calyx are observed in fat-suppressed coronal T2W and coronal dynamic T1W excretory phase images (although not visible in the images, proximal ureteral collapse). C-E. Automatic functional analysis of MR urography data after segmentation of the abdominal aorta, right (blue) and left (green) kidney parenchyma using CHOP fMRU software. D. Calculation of contrast curves. RTT values for right and left kidneys were 30 sec vs 2 sec, respectively. Volumes of right and left kidneys were 21 mL and 53 mL, respectively. SRF values of right and left kidneys were 28.48% and 71.52%, respectively.\u003c/p\u003e","description":"","filename":"2.png","url":"https://assets-eu.researchsquare.com/files/rs-7255640/v1/a76d9f66fb855dc83b69519c.png"},{"id":103251216,"identity":"c0ab1e13-ef65-408e-b9fa-7d3ab9700188","added_by":"auto","created_at":"2026-02-23 16:06:24","extension":"pdf","order_by":0,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":977238,"visible":true,"origin":"","legend":"","description":"","filename":"manuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-7255640/v1/91b4125c-4d5f-43f2-9707-ab706063661a.pdf"},{"id":88424077,"identity":"9f799cea-a9dd-4871-85a7-b9afc3bfeaa9","added_by":"auto","created_at":"2025-08-06 09:44:16","extension":"pptx","order_by":1,"title":"","display":"","copyAsset":false,"role":"supplement","size":170102,"visible":true,"origin":"","legend":"","description":"","filename":"renamedd5f99.pptx","url":"https://assets-eu.researchsquare.com/files/rs-7255640/v1/89b9cd4efaf527f1561e44ae.pptx"}],"financialInterests":"","formattedTitle":"Prediction of Split Renal Function and Obstruction with MR Urography in Comparison with Dynamic Renal Scintigraphy","fulltext":[{"header":"Introduction","content":"\u003cp\u003eMagnetic Resonance Urography (MRU) is of extremely important for detecting congenital malformations and acquired pathologies related to the kidneys and urinary tract in pediatric patients. Its noninvasive nature and lack of ionizing radiation make it a safe option, while its ability to provide detailed morphological and functional assessments facilitates comprehensive care [\u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e, \u003cspan citationid=\"CR2\" class=\"CitationRef\"\u003e2\u003c/span\u003e]. Congenital malformations present a wide range of challenges, from harmless renal ectopia to potentially fatal bilateral renal agenesis. Rapid diagnosis and functional evaluation are crucial to determine appropriate treatment and achieve early functional recovery. This is particularly important because concomitant obstructive uropathy is a leading cause of renal failure in infancy [\u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e3\u003c/span\u003e]. By prioritizing early intervention, we can significantly improve outcomes and protect the health of our youngest patients.\u003c/p\u003e\u003cp\u003eUltrasonography (USG) and Computed Tomography (CT) are the primary radiological techniques for assessing the structure of the kidneys and urinary tract. However, for a more in-depth understanding of renal function, MRU stands out by providing critical functional data. Additionally, the voiding cystourethrogram (VCUG) not only provides vital anatomical details but also enables dynamic evaluation of the urinary system. Adopting these methods ensures a comprehensive assessment for optimal patient care. Integrating radionuclide scintigraphy with radiologic techniques in the evaluation of renal function, significantly improves diagnostic accuracy. Notably, dimercaptosuccinic acid (Tc-99m-DMSA), mercaptoacetyltriglycine (Tc-99m-MAG3), and diethylenetriaminepentaacetic acid (Tc-99m-DTPA) are vital tools in nuclear medicine, providing invaluable insights into renal health [\u003cspan citationid=\"CR4\" class=\"CitationRef\"\u003e4\u003c/span\u003e]. USG is a widely used tool in the evaluation of the urinary system in children, and performs effectively in identifying mildly and moderately dilated collecting systems. However, it falls short in evaluating nondilated or severely dilated collecting systems, highlighting the need for alternative diagnostic options to ensure comprehensive care and accurate assessment. It is not feasible to assess split renal function (SRF) using USG, because the accuracy of the results is significantly affected by the operator's expertise. MAG3 dynamic renal scintigraphy is considered the definitive gold standard for accurately assessing SRF and effectively identifying obstructions, making it an indispensable tool in modern renal diagnostics [\u003cspan citationid=\"CR5\" class=\"CitationRef\"\u003e5\u003c/span\u003e]. Although MAG3 scintigraphy can effectively assess SRF and the collecting system, radiation exposure and poor anatomical detail due to low spatial resolution are limiting factors for its use.\u003c/p\u003e\u003cp\u003eMRU, due to its high spatial and contrast resolution, is an effective imaging technique for evaluating urinary system anatomy. In addition to assessing obstructive conditions through dynamic examinations, it also provides functional data through post-processing image analysis [\u003cspan citationid=\"CR6\" class=\"CitationRef\"\u003e6\u003c/span\u003e]. MRU is increasingly utilized, due to rapid imaging sequences that enable image acquisition during breath-hold periods and contrast medium-enhanced studies that include dynamic measurements [\u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e7\u003c/span\u003e]. MRU is a benefical imaging modality for the urinary tract in children, providing comprehensive anatomical and functional data while producing relatively high-quality images without the use of ionizing radiation. The literature reveals a remarkable paucity of comparative and quantitative functional studies that directly assess MAG3 scintigraphy versus contrast-enhanced MRU. This lack of research contributes to a limited understanding of how MRU performs compared to MAG3 scintigraphy, and highlights the need for further investigation in this area [\u003cspan additionalcitationids=\"CR9\" citationid=\"CR8\" class=\"CitationRef\"\u003e8\u003c/span\u003e–\u003cspan citationid=\"CR10\" class=\"CitationRef\"\u003e10\u003c/span\u003e]. This study aims to significantly advance our knowledge of SRF by comparing MRU and MAG3 scintigraphy. Moreover, it aims to provide valuable insights into obstruction prediction.\u003c/p\u003e"},{"header":"Material and Method","content":"\u003cp\u003eIn the current study, we evaluated dynamic MRU and dynamic renal scintigraphy using MAG3 in 90 patients. These patients were followed for congenital urinary system anomalies at our hospital between 2006 and 2021. None of the patients had a history of urinary tract infection or surgical intervention within the previous six months. The evaluation was conducted retrospectively by a nuclear medicine specialist and two radiologists, one of whom is board-certified. Informed consent was waived due to the retrospective nature of the study. The study was approved by the local Ethics Committee on October 12, 2021 (File Number: 22).\u003c/p\u003e\u003cp\u003eMRU examinations were performed in the supine position using a 1.5 Tesla device (Magnetom Symphony and Magnetom Aera, Siemens Healthcare). A head coil or a phased array receiver coil was used, depending on the patient's body size. After localizer images were obtained in all three planes, coronal and axial plane images were obtained using a HASTE (single-shot fast spin echo) sequence. Imaging began at the superior aspect of the diaphragm and continued down to the bladder. T1- and T2-weighted images were obtained, and the static examination was completed with heavy T2 sequences in the coronal plane. A T1-weighted 3D gradient echo sequence was used for dynamic analysis. Our clinic's hydration protocol for MRU examination includes the administration of 20 mL/kg of saline 30 minutes prior to the study, followed by 10 mL/kg during the examination. After ensuring that patients were well-hydrated and had satisfactory urine output, intravenous furosemide was administered at a dose of 0.3 mg/kg to facilitate visualization of the collecting system. Following initial images obtained without contrast material, a contrast agent (gadobutrol and gadoterate meglumin) was administered as an IV bolus at a dose of 0.1 mmol/kg. Dynamic examinations were then completed by obtaining additional images.\u003c/p\u003e\u003cp\u003eThe diuretic renal scintigraphy utilized Tc99m-MAG3, which is the preferred radioisotope for the pediatric population. Prior to the procedure, patients received oral or intravenous hydration, depending on their age. Posterior dynamic images were captured after injecting 3.7 MBq/kg of the radionuclide agent and 1 mg/kg of furosemide (with a maximum dose of 20 mg). A nuclear medicine specialist evaluated the images and determined Tmax, T1/2, and SRF values.\u003c/p\u003e\u003cp\u003eUrinary tract morphology was assessed using various parameters during MRU examinations, including parenchyma thickness, anterior-posterior diameter of the renal pelvis, and kidney dimensions obtained from conventional sequences. Temporal and quantitative data regarding SRF and renal transit time (RTT) were gathered using the semi-automated MR urography software developed by the Children's Hospital of Philadelphia (CHOP). SRFs obtained by MRU were compared with the results of MAG3 scintigraphy, the standard method used before MRU examinations. To assess urinary system obstruction in the same patient group, we evaluated T1/2, which represents the time required for renal activity to decrease to 50% of its maximum value calculated by MAG3 scintigraphy, and RTT, which represents the time required for the contrast agent to be visualized in the ureteral segment below the lower pole of the related kidney, observed in the arterial phase of the renal cortex on dynamic post-contrast imaging [\u003cspan citationid=\"CR11\" class=\"CitationRef\"\u003e11\u003c/span\u003e]. Considering the RTT, urinary tract obstruction detection was classified as normal (RTT ≤ 245 sec), suspicious (245 \u0026lt; RTT ≤ 490 sec), or obstructed (RTT \u0026gt; 490 sec) as given in the latest study [\u003cspan citationid=\"CR12\" class=\"CitationRef\"\u003e12\u003c/span\u003e]. In scintigraphy, which is the reference method for demonstrating obstruction, cases with T1/2 time greater than 20 minutes were selected, and the sensitivity, specificity, and positive and negative predictive values of RTT in the assessment of urinary tract obstruction ​​were analyzed.\u003c/p\u003e\u003cp\u003eStatistical analyses were performed using the NCSS (Number Cruncher Statistical System) program. Study data were evaluated using descriptive statistical methods (mean, standard deviation, median, minimum, and maximum). The Shapiro-Wilk test and graphical analyses were used to ensure compliance of quantitative data with normal distribution. The Student-t test was used to compare quantitative variables with normal distribution between two groups, and the Mann-Whitney U test was used to compare quantitative variables with non-normal distribution. McNemar goodness of fit test and diagnostic screening tests were used to compare qualitative data. Pearson correlation analysis was used to evaluate relationships between quantitative variables. Statistical significance was accepted as p \u0026lt; 0.05.\u003c/p\u003e"},{"header":"Results","content":"\u003cp\u003eA total of 90 patients; 43 females (48%), and 47 males (52%), participated in the study. The ages of the cases ranged from 1 to 216 months. The mean and standard deviation (Mean\u0026thinsp;\u0026plusmn;\u0026thinsp;SD) for all the participants were 76.82\u0026thinsp;\u0026plusmn;\u0026thinsp;62.59 months.\u003c/p\u003e\u003cp\u003eThe diagnoses made to the patients as a result of clinical evaluation and MR imaging were determined as; ureteropelvic junction obstruction (n:37), double collecting system (n:15), unilateral renal agenesis (n:6), vesicoureteral reflux (n:9), ureterovesical junction obstruction (n:6), congenital megaureter (n:4), multicystic dysplastic kidney (n:3), horseshoe kidney (n:2), ureterocele (n:2), posterior urethral valve (n:1), renal hypoplasia (n:3), bladder exstrophy (n:1), and neurogenic bladder (n:1).\u003c/p\u003e\u003cp\u003eThe morphological evaluation results regarding the size, parenchymal thickness, renal pelvis and ureter diameter, and renal volume in each ureteropelvic unit 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\u003eEvaluation of Morphological Parameters in Ureteropelvic Units\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=\"left\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c4\" colnum=\"4\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" 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\u0026nbsp;\u003c/th\u003e\u003cth align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/th\u003e\u003cth align=\"left\" colspan=\"2\" nameend=\"c4\" namest=\"c3\"\u003e\u003cp\u003eLeft (n:95)\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c5\"\u003e\u003cp\u003eRight (n:93)\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c6\"\u003e\u003cp\u003ep\u003c/p\u003e\u003c/th\u003e\u003c/tr\u003e\u003c/thead\u003e\u003ctbody\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eSize (mm)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003eMean\u0026thinsp;\u0026plusmn;\u0026thinsp;SD\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colspan=\"2\" nameend=\"c4\" namest=\"c3\"\u003e\u003cp\u003e79.29\u0026thinsp;\u0026plusmn;\u0026thinsp;29.81\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e79.92\u0026thinsp;\u0026plusmn;\u0026thinsp;25.85\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e\u003csup\u003e\u003cem\u003ea\u003c/em\u003e\u003c/sup\u003e\u003cem\u003e0.876\u003c/em\u003e\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colspan=\"2\" nameend=\"c3\" namest=\"c2\"\u003e\u003cp\u003eMedian(Min-Max)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e80.4 (22\u0026ndash;151)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e79.9 (17\u0026ndash;156)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u0026nbsp;\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eParenchymal Thickness (mm)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colspan=\"2\" nameend=\"c3\" namest=\"c2\"\u003e\u003cp\u003eMean\u0026thinsp;\u0026plusmn;\u0026thinsp;SD\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e9.96\u0026thinsp;\u0026plusmn;\u0026thinsp;9.46\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e10.79\u0026thinsp;\u0026plusmn;\u0026thinsp;9.42\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e\u003csup\u003e\u003cem\u003eb\u003c/em\u003e\u003c/sup\u003e\u003cem\u003e0.308\u003c/em\u003e\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colspan=\"2\" nameend=\"c3\" namest=\"c2\"\u003e\u003cp\u003eMedian(Min-Max)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e8.4 (0\u0026ndash;87)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e9.7 (0\u0026ndash;85)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u0026nbsp;\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eAP Diameter of Renal Pelvis (mm)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colspan=\"2\" nameend=\"c3\" namest=\"c2\"\u003e\u003cp\u003eMean\u0026thinsp;\u0026plusmn;\u0026thinsp;SD\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e13.55\u0026thinsp;\u0026plusmn;\u0026thinsp;12.84\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e10.98\u0026thinsp;\u0026plusmn;\u0026thinsp;9.25\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e\u003csup\u003e\u003cem\u003eb\u003c/em\u003e\u003c/sup\u003e\u003cem\u003e0.459\u003c/em\u003e\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colspan=\"2\" nameend=\"c3\" namest=\"c2\"\u003e\u003cp\u003eMedian(Min-Max)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e7.9 (0-52.2)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e8.7 (0-51.8)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u0026nbsp;\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eUreter Diameter (mm)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colspan=\"2\" nameend=\"c3\" namest=\"c2\"\u003e\u003cp\u003eMean\u0026thinsp;\u0026plusmn;\u0026thinsp;SD\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e5.83\u0026thinsp;\u0026plusmn;\u0026thinsp;5.42\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e4.32\u0026thinsp;\u0026plusmn;\u0026thinsp;4.56\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e\u003csup\u003e\u003cem\u003eb\u003c/em\u003e\u003c/sup\u003e\u003cem\u003e0.012*\u003c/em\u003e\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colspan=\"2\" nameend=\"c3\" namest=\"c2\"\u003e\u003cp\u003eMedian(Min-Max)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e3.2 (0-28.8)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e2.5 (1-23.7)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u0026nbsp;\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eVolume (mL)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colspan=\"2\" nameend=\"c3\" namest=\"c2\"\u003e\u003cp\u003eMean\u0026thinsp;\u0026plusmn;\u0026thinsp;SD\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e51.00\u0026thinsp;\u0026plusmn;\u0026thinsp;43.83\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e54.42\u0026thinsp;\u0026plusmn;\u0026thinsp;34.98\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e\u003csup\u003e\u003cem\u003eb\u003c/em\u003e\u003c/sup\u003e\u003cem\u003e0.117\u003c/em\u003e\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colspan=\"2\" nameend=\"c3\" namest=\"c2\"\u003e\u003cp\u003eMedian(Min-Max)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e39 (2-265)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e47 (0-171)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u0026nbsp;\u003c/td\u003e\u003c/tr\u003e\u003c/tbody\u003e\u003c/colgroup\u003e\u003ctfoot\u003e\u003ctr\u003e\u003ctd colspan=\"6\"\u003e\u003csup\u003e\u003cem\u003ea\u003c/em\u003e\u003c/sup\u003e\u003cb\u003eStudent-t Test\u003c/b\u003e, \u003csup\u003e\u003cem\u003eb\u003c/em\u003e\u003c/sup\u003e\u003cem\u003eMann Whitney U Test, *p\u0026thinsp;\u0026lt;\u0026thinsp;0.05 was depicted as statistically significant.\u003c/em\u003e\u003c/td\u003e\u003c/tr\u003e\u003c/tfoot\u003e\u003c/table\u003e\u003c/div\u003e\u003c/p\u003e\u003cp\u003eWhen a total of 188 ureteropelvic units; (93 right, 95 left), were examined, dilatation was detected in 95 (50.5%) of the units, while pelvicaliectasis was not observed in 93 (49.5%). Of the dilated units, 45 (47%) were located on the right side, and 50 (53%) were located on the left side. When urinary system obstructions were evaluated, 46.6% of the obstructions were detected in the right collecting system and 53.4% in the left collecting system. No statistically significant differences were detected between renal pelvis measurements, parenchymal thickness, AP diameter, and right and left kidney volumes (p\u0026thinsp;\u0026gt;\u0026thinsp;0.05).\u003c/p\u003e\u003cp\u003eA weak positive correlation between the AP diameter of renal pelvis and kidney size was found to be statistically significant (r\u0026thinsp;=\u0026thinsp;0.345; p\u0026thinsp;=\u0026thinsp;0.001). A negative correlation between the AP diameter of the renal pelvis and parenchymal thickness of the cases included in the study was found to be statistically significant (r=-0.323; p\u0026thinsp;=\u0026thinsp;0.001).\u003c/p\u003e\u003cp\u003ePatients with unilateral renal agenesis (6 patients), multicystic dysplastic kidney (3 patients), and 5 patients in whom the renal parenchymal segmentation could not be performed due to motion artifact in dynamic studies were excluded from functional evaluation on dynamic MRU sequences. Since there was no MAG3 scintigraphy data divided into upper and lower systems for comparison in cases with double collecting systems, each kidney was evaluated as a ureteropelvic unit, regardless of the number of collecting systems. A total of 152 kidneys of the remaining 76 patients, 76 right and 76 left, were quantitatively evaluated on dynamic images. The mean time interval between scintigraphy and MRU examinations was 41\u0026thinsp;\u0026plusmn;\u0026thinsp;29 days. The mean right SRF measurements obtained by scintigraphy for the individuals participating in the study were 52.58\u0026thinsp;\u0026plusmn;\u0026thinsp;17.84%, and the mean left SRF measurements were 47.42\u0026thinsp;\u0026plusmn;\u0026thinsp;17.84%. The mean right SRF measurements obtained with functional MRU were 53.03\u0026thinsp;\u0026plusmn;\u0026thinsp;14.46%, and the mean left SRF measurements were 46.87\u0026thinsp;\u0026plusmn;\u0026thinsp;14.50%. Very strong positive correlations were obtained between dynamic renal scintigraphy and dynamic MRU-based right (r\u0026thinsp;=\u0026thinsp;0.937; p\u0026thinsp;=\u0026thinsp;0.001) and left (r\u0026thinsp;=\u0026thinsp;0.936; p\u0026thinsp;=\u0026thinsp;0.001) SRF measurements (Table\u0026nbsp;\u003cspan refid=\"Tab2\" class=\"InternalRef\"\u003e2\u003c/span\u003e, Fig.\u0026nbsp;\u003cspan refid=\"Fig1\" class=\"InternalRef\"\u003e1\u003c/span\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\u003eDistribution of Dynamic Renal Scintigraphy and Dynamic MR Urography SRF Measurements\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=\"left\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c4\" colnum=\"4\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" 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\" colspan=\"4\" nameend=\"c4\" namest=\"c1\"\u003e\u0026nbsp;\u003c/th\u003e\u003cth align=\"left\" colname=\"c5\"\u003e\u003cp\u003ep\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c6\"\u003e\u003cp\u003er*\u003c/p\u003e\u003c/th\u003e\u003c/tr\u003e\u003c/thead\u003e\u003ctbody\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\" morerows=\"3\" rowspan=\"4\"\u003e\u003cp\u003e\u003cb\u003eRight\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\" morerows=\"1\" rowspan=\"2\"\u003e\u003cp\u003e\u003cb\u003eSRF Scintigraphy\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003eMean\u0026thinsp;\u0026plusmn;\u0026thinsp;SD\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e52.58\u0026thinsp;\u0026plusmn;\u0026thinsp;17.84\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\" morerows=\"3\" rowspan=\"4\"\u003e\u003cp\u003e0.001\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\" morerows=\"3\" rowspan=\"4\"\u003e\u003cp\u003e0.937\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003eMedian(Min-Max)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e52.5 (0-100)\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c2\" morerows=\"1\" rowspan=\"2\"\u003e\u003cp\u003e\u003cb\u003eSRF MRU\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003eMean\u0026thinsp;\u0026plusmn;\u0026thinsp;SD\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e53.03\u0026thinsp;\u0026plusmn;\u0026thinsp;14.46\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003eMedian(Min-Max)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e52.5 (12\u0026ndash;87)\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\" morerows=\"3\" rowspan=\"4\"\u003e\u003cp\u003e\u003cb\u003eLeft\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\" morerows=\"1\" rowspan=\"2\"\u003e\u003cp\u003e\u003cb\u003eSRF Scintigraphy\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003eMean\u0026thinsp;\u0026plusmn;\u0026thinsp;SD\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e47.42\u0026thinsp;\u0026plusmn;\u0026thinsp;17.84\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\" morerows=\"3\" rowspan=\"4\"\u003e\u003cp\u003e0.001\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\" morerows=\"3\" rowspan=\"4\"\u003e\u003cp\u003e0.936\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003eMedian(Min-Max)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e47.5 (0-100)\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c2\" morerows=\"1\" rowspan=\"2\"\u003e\u003cp\u003e\u003cb\u003eSRF MRU\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003eMean\u0026thinsp;\u0026plusmn;\u0026thinsp;SD\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e46.87\u0026thinsp;\u0026plusmn;\u0026thinsp;14.50\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003eMedian(Min-Max)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e47.5 (13\u0026ndash;88)\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003c/tbody\u003e\u003c/colgroup\u003e\u003ctfoot\u003e\u003ctr\u003e\u003ctd colspan=\"6\"\u003e*r\u0026thinsp;=\u0026thinsp;Pearson Correlation Coefficient\u003c/td\u003e\u003c/tr\u003e\u003c/tfoot\u003e\u003c/table\u003e\u003c/div\u003e\u003c/p\u003e\u003cp\u003e\u003c/p\u003e\u003cp\u003eWhen ipsilateral ureteropelvic units were grouped according to the presence of obstruction based on scintigraphic findings, SRF values of obstructed units were found to be significantly lower than those of non-obstructed units for both the right and left side (Table\u0026nbsp;\u003cspan refid=\"Tab3\" class=\"InternalRef\"\u003e3\u003c/span\u003e\u003cb\u003e)\u003c/b\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\u003eComaprison of Dynamic Renal Scintigraphy and Dynamic MR Urography based SRF Measurements According to Presence of Obstruction\u003c/p\u003e\u003c/div\u003e\u003c/caption\u003e\u003ccolgroup cols=\"7\"\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\u003cdiv align=\"left\" class=\"colspec\" colname=\"c4\" colnum=\"4\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c5\" colnum=\"5\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c6\" colnum=\"6\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c7\" colnum=\"7\"\u003e\u003c/div\u003e\u003cthead\u003e\u003ctr\u003e\u003cth align=\"left\" colspan=\"2\" nameend=\"c2\" namest=\"c1\"\u003e\u0026nbsp;\u003c/th\u003e\u003cth align=\"left\" colspan=\"2\" nameend=\"c4\" namest=\"c3\"\u003e\u003cp\u003eWith Obstruction\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colspan=\"2\" nameend=\"c6\" namest=\"c5\"\u003e\u003cp\u003eWithout Obstruction\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c7\"\u003e\u003cp\u003ep\u003c/p\u003e\u003c/th\u003e\u003c/tr\u003e\u003c/thead\u003e\u003ctbody\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\" morerows=\"1\" rowspan=\"2\"\u003e\u003cp\u003e\u003cb\u003eRight\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e\u003cb\u003eSRF Scintigraphy\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003eMean\u0026thinsp;\u0026plusmn;\u0026thinsp;SD\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e51.75\u0026thinsp;\u0026plusmn;\u0026thinsp;7.44\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003eMean\u0026thinsp;\u0026plusmn;\u0026thinsp;SD\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e61.14\u0026thinsp;\u0026plusmn;\u0026thinsp;15.5\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c7\"\u003e\u003cp\u003e\u003cb\u003e0.04\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e\u003cb\u003eSRF MRU\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003eMean\u0026thinsp;\u0026plusmn;\u0026thinsp;SD\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e52.05\u0026thinsp;\u0026plusmn;\u0026thinsp;8.3\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003eMean\u0026thinsp;\u0026plusmn;\u0026thinsp;SD\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e59.01\u0026thinsp;\u0026plusmn;\u0026thinsp;14.35\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c7\"\u003e\u003cp\u003e\u003cb\u003e0.045\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\" morerows=\"1\" rowspan=\"2\"\u003e\u003cp\u003e\u003cb\u003eLeft\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e\u003cb\u003eSRF Scintigraphy\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003eMean\u0026thinsp;\u0026plusmn;\u0026thinsp;SD\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e42.42\u0026thinsp;\u0026plusmn;\u0026thinsp;17.84\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003eMean\u0026thinsp;\u0026plusmn;\u0026thinsp;SD\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e53.4\u0026thinsp;\u0026plusmn;\u0026thinsp;12.08\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c7\"\u003e\u003cp\u003e\u003cb\u003e0.035\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e\u003cb\u003eSRF MRU\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003eMean\u0026thinsp;\u0026plusmn;\u0026thinsp;SD\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e43.01\u0026thinsp;\u0026plusmn;\u0026thinsp;11.4\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003eMean\u0026thinsp;\u0026plusmn;\u0026thinsp;SD\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e53.02\u0026thinsp;\u0026plusmn;\u0026thinsp;13.17\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c7\"\u003e\u003cp\u003e\u003cb\u003e0.037\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003c/tbody\u003e\u003c/colgroup\u003e\u003c/table\u003e\u003c/div\u003e\u003c/p\u003e\u003cp\u003eAmong the right kidneys, 48 cases with urinary obstruction were found according to the T1/2 by scintigraphy. Thirty-one of these cases were found to be positive, while 17 were found to be negative in terms of obstruction by RTT. Accordingly, the sensitivity, specificity, positive and negative predictive values, and accuracy of RTT were found to be 64.58%, 85.71%, 88.57%, 58.54%, and 72.37%, respectively (Table\u0026nbsp;\u003cspan refid=\"Tab4\" class=\"InternalRef\"\u003e4\u003c/span\u003e\u003cb\u003e).\u003c/b\u003e Among the left kidneys, 55 cases with urinary obstruction were found according to the T1/2 by scintigraphy. Thirty-six of these cases were found to be positive by RTT. In 17 cases both RTT and T1/2 time excluded obstruction. Accordingly, the sensitivity, specificity, positive and negative predictive values, and accuracy of RTT were 65.45%, 80.95%, 90%, 47.22%, and 69.74%, respectively \u003cb\u003e(\u003c/b\u003eTable\u0026nbsp;\u003cspan refid=\"Tab5\" class=\"InternalRef\"\u003e5\u003c/span\u003e, Fig.\u0026nbsp;\u003cspan refid=\"Fig2\" class=\"InternalRef\"\u003e2\u003c/span\u003e\u003cb\u003e)\u003c/b\u003e. Among all the kidneys, the sensitivity, specificity, positive and negative predictive values of RTT for urinary obstruction were depicted as 65%, 83%, 90%, and 53%, respectively.\u003c/p\u003e\u003cp\u003e\u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab4\" border=\"1\"\u003e\u003ccaption language=\"En\"\u003e\u003cdiv class=\"CaptionNumber\"\u003eTable 4\u003c/div\u003e\u003cdiv class=\"CaptionContent\"\u003e\u003cp\u003eEvaluation of T1/2 and RTT Compliance for the Right Urinary System\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=\"left\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c4\" colnum=\"4\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" 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\u003eRight Side\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/th\u003e\u003cth align=\"left\" colspan=\"2\" nameend=\"c4\" namest=\"c3\"\u003e\u003cp\u003eT1/2 (scintigraphy(min))\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/th\u003e\u003cth align=\"left\" colname=\"c6\"\u003e\u0026nbsp;\u003c/th\u003e\u003c/tr\u003e\u003c/thead\u003e\u003ctbody\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e\u003cb\u003eObstruction\u003c/b\u003e\u003c/p\u003e\u003cp\u003e\u003cb\u003e(+)\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e\u003cb\u003eObstruction\u003c/b\u003e\u003c/p\u003e\u003cp\u003e\u003cb\u003e(-)\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e\u003cb\u003eTotal\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u0026nbsp;\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003eN (%)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003en(%)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003en(%)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003ep\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\" morerows=\"2\" rowspan=\"3\"\u003e\u003cp\u003eRTT(MRU(min))\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e\u003cb\u003eObstruction (+)\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e31 (40.8)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e4 (5.3)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e35 (46.1)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e\u003cb\u003e0.007**\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e\u003cb\u003eObstruction (-)\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e17 (22.4)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e24 (31.6)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e41 (53.9)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u0026nbsp;\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e\u003cb\u003eTotal n (%)\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e48 (63.2)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e28 (36.8)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e76 (100.0)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u0026nbsp;\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colspan=\"6\" nameend=\"c6\" namest=\"c1\"\u003e\u003cp\u003eDiagnostic Test Results (%)\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eSensitivity\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colspan=\"5\" nameend=\"c6\" namest=\"c2\"\u003e\u003cp\u003e64.58\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eSpecificity\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colspan=\"5\" nameend=\"c6\" namest=\"c2\"\u003e\u003cp\u003e85.71\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003ePositive Predictive Value\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colspan=\"5\" nameend=\"c6\" namest=\"c2\"\u003e\u003cp\u003e88.57\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eNegative Predictive Value\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colspan=\"5\" nameend=\"c6\" namest=\"c2\"\u003e\u003cp\u003e58.54\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eDiagnostic Accuracy\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colspan=\"5\" nameend=\"c6\" namest=\"c2\"\u003e\u003cp\u003e72.37\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003c/tbody\u003e\u003c/colgroup\u003e\u003ctfoot\u003e\u003ctr\u003e\u003ctd colspan=\"6\"\u003eMcNemar Test \u003cem\u003e**p\u0026thinsp;\u0026lt;\u0026thinsp;0.01\u003c/em\u003e\u003c/td\u003e\u003c/tr\u003e\u003c/tfoot\u003e\u003c/table\u003e\u003c/div\u003e\u003c/p\u003e\u003cp\u003e\u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab5\" border=\"1\"\u003e\u003ccaption language=\"En\"\u003e\u003cdiv class=\"CaptionNumber\"\u003eTable 5\u003c/div\u003e\u003cdiv class=\"CaptionContent\"\u003e\u003cp\u003eEvaluation of T1/2 and RTT Compliance for the Left Urinary System\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=\"left\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c4\" colnum=\"4\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" 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\u003eLeft Side\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/th\u003e\u003cth align=\"left\" colspan=\"2\" nameend=\"c4\" namest=\"c3\"\u003e\u003cp\u003eT1/2 (scintigraphy (min) )\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/th\u003e\u003cth align=\"left\" colname=\"c6\"\u003e\u0026nbsp;\u003c/th\u003e\u003c/tr\u003e\u003c/thead\u003e\u003ctbody\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e\u003cb\u003eObstruction\u003c/b\u003e\u003c/p\u003e\u003cp\u003e\u003cb\u003e(+)\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e\u003cb\u003eObstruction\u003c/b\u003e\u003c/p\u003e\u003cp\u003e\u003cb\u003e(-)\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e\u003cb\u003eTotal\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u0026nbsp;\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003en (%)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003en (%)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003eN (%)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e\u003cb\u003ep\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eRTT(MRU(min))\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003eObstruction (+)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e36 (47.4)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e4 (5.3)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e40 (52.6)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e\u003cb\u003e0.003**\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003eObstruction (-)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e19 (25.0)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e17 (22.4)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e36 (47.4)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u0026nbsp;\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003eTotal\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e55 (72.4)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e21 (27.6)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e76 (100.0)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u0026nbsp;\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eDiagnostic Test Results (%)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colspan=\"5\" nameend=\"c6\" namest=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eSensitivity\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e65.45\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u0026nbsp;\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eSpecificity\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e80.95\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u0026nbsp;\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003ePositive Predictive Value\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e90.00\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u0026nbsp;\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eNegative Predictive Value\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e47.22\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u0026nbsp;\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eDiagnostic Accuracy\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e69.74\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u0026nbsp;\u003c/td\u003e\u003c/tr\u003e\u003c/tbody\u003e\u003c/colgroup\u003e\u003ctfoot\u003e\u003ctr\u003e\u003ctd colspan=\"6\"\u003eMcNemar Test \u003cem\u003e**p\u0026thinsp;\u0026lt;\u0026thinsp;0.01\u003c/em\u003e\u003c/td\u003e\u003c/tr\u003e\u003c/tfoot\u003e\u003c/table\u003e\u003c/div\u003e\u003c/p\u003e\u003cp\u003e\u003c/p\u003e"},{"header":"Discussion","content":"\u003cp\u003eIn our study, volumetric SRF was calculated by converting the enhanced renal parenchymal volume into percentages, with the assumption that the right and left kidneys account for 100% of the renal function via the software and compared with MAG3 scintigraphy results, currently considered the reference method for renal functions. SRF obtained from MRU examinations of the right and left kidneys showed highly significant positive correlations with MAG3 scintigraphy results. In addition, we achieved acceptable and promising diagnostic accuracy of MRU in the diagnosis of urinary obstruction at the level of pelvicalyceal system.\u003c/p\u003e\u003cp\u003eSRF represents the function of a kidney relative to total kidney function and is an important measure in renal health assessment. Renal scintigraphy is the standard method for determining SRF, and MAG3 scintigraphy is currently considered the gold standard due to its accuracy in detecting SRF [\u003cspan citationid=\"CR13\" class=\"CitationRef\"\u003e13\u003c/span\u003e]. This method not only detects SRF but also evaluates urinary tract obstructions. When used in conjunction with USG, which provides detailed anatomical information about the kidneys and collecting system, these techniques provide essential complementary information [\u003cspan citationid=\"CR14\" class=\"CitationRef\"\u003e14\u003c/span\u003e]. However, it is important to consider the drawbacks of this combination such as exposure to ionizing radiation during scintigraphy, and the operator-dependent nature of USG especially when it struggles to visualize both non-dilated and extremely dilated collecting systems. This limitation highlights the urgent need for alternative imaging modalities that enhance diagnostic accuracy and patient safety.\u003c/p\u003e\u003cp\u003eRecently, Computed Tomography Urography (CTU) and functional MRU have been proposed as alternatives to conventional methods for estimating SRF [\u003cspan citationid=\"CR14\" class=\"CitationRef\"\u003e14\u003c/span\u003e]. CTU-based estimation of SRF relies on the amount of contrast medium excreted by the kidneys. Shi et al. demonstrated that combining CTU images of the nephrographic phase with serum creatinine levels successfully determined SRF [\u003cspan citationid=\"CR15\" class=\"CitationRef\"\u003e15\u003c/span\u003e]. You et al. revealed a good correlation between the scintigraphy and CTU in terms of the determination of SRF enabling the evaluation of renal function without additional radiation dose [\u003cspan citationid=\"CR16\" class=\"CitationRef\"\u003e16\u003c/span\u003e]. A comparison of CTU and routine reference scintigraphy to estimete SRF was evaluated in a prospective study conducted by Yuan et al. The findings were satisfactory and resulted in accurate measurements [\u003cspan citationid=\"CR17\" class=\"CitationRef\"\u003e17\u003c/span\u003e]. Nonetheless, CTU employs ionizing radiation, and there are contraindications to the use of iodine-based contrast medium in certain patient groups, necessitating the consideration of alternative modalities.\u003c/p\u003e\u003cp\u003eRecent studies have proposed the use of functional MRU as an alternative to conventional studies for evaluating SRF in patients with obstructive uropathy [\u003cspan citationid=\"CR8\" class=\"CitationRef\"\u003e8\u003c/span\u003e, \u003cspan citationid=\"CR9\" class=\"CitationRef\"\u003e9\u003c/span\u003e, \u003cspan citationid=\"CR14\" class=\"CitationRef\"\u003e14\u003c/span\u003e, \u003cspan citationid=\"CR18\" class=\"CitationRef\"\u003e18\u003c/span\u003e]. Functional MRU is rapidly becoming a vital tool in daily medical practice, as it allows for precise determination of morphological details. Its advanced capability to distinguish the signal intensities of soft tissue components provides exceptional soft tissue contrast, making it an invaluable asset for accurate diagnosis and treatment planning [\u003cspan citationid=\"CR19\" class=\"CitationRef\"\u003e19\u003c/span\u003e, \u003cspan citationid=\"CR20\" class=\"CitationRef\"\u003e20\u003c/span\u003e]. This approach is highly effective in the management of complex congenital anomalies of the kidney and urinary tract (CAKUT) and offers the significant advantage of completely eliminating exposure to ionizing radiation [\u003cspan citationid=\"CR5\" class=\"CitationRef\"\u003e5\u003c/span\u003e]. Studies comparing scintigraphic methods and MRU in evaluating SRF have demonstrated a significant correlation between the two approaches. Furthermore, MRU stands out by providing precise measurements of the contrast enhanced renal parenchymal volume, making it a valuable tool in clinical practice [\u003cspan citationid=\"CR10\" class=\"CitationRef\"\u003e10\u003c/span\u003e, \u003cspan citationid=\"CR21\" class=\"CitationRef\"\u003e21\u003c/span\u003e]. Although MRU has a significant role in the assessment of SRF, due to the lack of comprehensive studies comparing the two techniques in the current literature, scintigraphic studies are still considered the reference method for the evaluation of obstructive uropathy as well as for guiding treatment decisions [\u003cspan citationid=\"CR5\" class=\"CitationRef\"\u003e5\u003c/span\u003e]. Damasio et al. found no significant difference in the drainage curves between MRU and scintigraphic evaluations in patients with CAKUT [\u003cspan citationid=\"CR5\" class=\"CitationRef\"\u003e5\u003c/span\u003e]. Rodigas et al. demonstrated that functional MRU offers significant diagnostic advantages, making it an essential complementary examination for challenging cases [\u003cspan citationid=\"CR14\" class=\"CitationRef\"\u003e14\u003c/span\u003e]. Claudon et al. demonstrated that MRU is as effective as scintigraphy for moderately dilated collecting systems. Therefore, adopting MRU as a substitute for scintigraphy is not only advisable but also beneficial for enhancing diagnostic accuracy and efficiency [\u003cspan citationid=\"CR21\" class=\"CitationRef\"\u003e21\u003c/span\u003e].\u003c/p\u003e\u003cp\u003eSRF measurements have been obtained via signal-intensity curves in dynamic contrast-enhanced MR nephropraphy, 3D gradient echo sequence with compressed-sensing and paralel imaging reconstruction by considering and grouping renal functions, non-contrast MRU derived texture parameters in comparison with scintigraphy, and integrated diffusion tensor imaging and renal parenchymal volume compared with scintigraphy [\u003cspan additionalcitationids=\"CR23 CR24\" citationid=\"CR22\" class=\"CitationRef\"\u003e22\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR25\" class=\"CitationRef\"\u003e25\u003c/span\u003e]. Although some SRF results have been evaluated in comparison with scintigraphy, our study differs due to the patient group and methodologies, and direct comparisons can not be made. In a study closely aligning with our findings, volumetric SRF calculated with CHOP-fMRU software demonstrated a significant correlation with MAG3 scintigraphy data. This research, which included 58 patients, mostly diagnosed with ureteropelvic junction (UPJ) obstruction (57%), highlights the reliability of these imaging techniques [\u003cspan citationid=\"CR26\" class=\"CitationRef\"\u003e26\u003c/span\u003e]. In a recent investigation by Jurkiewicz et al. on 46 pediatric patients, MRU-based SRF was compared with renal scintigraphy utilizing 99mTc-ethylenedicysteine (99mTc-EC). A strong agreement observed between these two methods further strenghtens the reliability of our results and supports their use in clinical practice [\u003cspan citationid=\"CR27\" class=\"CitationRef\"\u003e27\u003c/span\u003e]. Additionally, a recent study comparing MRU with MAG3 scintigraphy to assess ureteropelvic junction obstruction demonstrated impressive correlation coefficients regarding relative renal functions, highlighting the reliability of MRU as a diagnostic tool in this context [\u003cspan citationid=\"CR28\" class=\"CitationRef\"\u003e28\u003c/span\u003e].\u003c/p\u003e\u003cp\u003eFunctional analysis data obtained from the two software programs, \u0026ldquo;CHOP-fMRU\u0026rdquo; and \u0026ldquo;Image J,\u0026rdquo; were meticulously compared with each other and with findings obtained from the 99mTc-Diethylenetriamine pentaacetate (DTPA) dynamic renal scintigraphy [\u003cspan citationid=\"CR29\" class=\"CitationRef\"\u003e29\u003c/span\u003e]. The results indicated that there were no statistically significant differences between caliceal and renal transit times, renal parenchymal volumes, and volumetric SRF when CHOP-fMRU and Image J were compared (p\u0026thinsp;\u0026gt;\u0026thinsp;0.05). Furthermore, the volumetric SRF values obtained from both CHOP-fMRU and Image J closely overlapped with the values obtained from the 99mTc-DTPA study, supporting the reliability of these imaging techniques.\u003c/p\u003e\u003cp\u003eThere is a distinct lack of quantitative and semiquantitative studies examining urinary obstruction using MRU in children. Utilizing parameters such as calyceal transit time, RTT, and mean transit time is crucial for a comprehensive quantitative assessment. Further research in this area could significantly improve our knowledge and management of urinary obstruction in pediatric patients. In a recent study, the RTT values in normal kidneys, were found to range from 2.37 to 6.52 minutes in those with a \u0026frac12; Tmax of less than 10 minutes as measured by MAG-3 scintigraphy. In contrast, kidneys exhibiting moderate uropathy, with a \u0026frac12; Tmax value between 10 and 15 minutes, had a RTT range of 4.13 to 12.32 minutes [\u003cspan citationid=\"CR30\" class=\"CitationRef\"\u003e30\u003c/span\u003e]. In a study comparing UPJ obstruction using MRU and MAG3 scintigraphy, MAG3 scintigraphy was considered the gold standard for obstruction when a half-life (T1/2) of 20 minutes or greater was established. A study using a cut-off value of 6 minutes for RTT on MRU revealed a sensitivity of 61.9%, a specificity of 94.1%, and an impressive area under the curve value of 0.8271. These results highlight the effectiveness of MRU in evaluating UPJ stenosis alongside MAG3 scintigraphy [\u003cspan citationid=\"CR31\" class=\"CitationRef\"\u003e31\u003c/span\u003e]. The remarkable correlation between the RTT values and T1/2 underscores its reliability, resulting in an impressive sensitivity of 100% and a specificity of 81.6%, making it a valuable tool in the diagnosis of urinary tract disorders [\u003cspan citationid=\"CR14\" class=\"CitationRef\"\u003e14\u003c/span\u003e].\u003c/p\u003e\u003cp\u003eJones et al. reported that the RTT obtained from MR urography examination and the half-life of renal signal decay obtained from dynamic renal scintigraphy were equally effective in predicting obstruction [\u003cspan citationid=\"CR12\" class=\"CitationRef\"\u003e12\u003c/span\u003e]. In our study, we used the same classification to demonstrate obstruction by calculating the RTT via the software for a total of 152 kidneys in 76 patients. Comparing our data with scintigraphy examinations with T1/2 periods longer than 20 minutes, which indicate obstruction, we identified 67 true positives, 8 false positives, 41 true negatives, and 36 false negatives in 152 kidneys. The negative predictive value was found to be 53%. All of the false-negative cases in our study fell within the suspicious (\u0026gt;\u0026thinsp;245\u0026thinsp;\u0026le;\u0026thinsp;490 sec) timeframe according to the classification. In our study, the specificity value for RTT was similar to the results of Rodigas at al. but lower than the results of Viteri at.al. [\u003cspan citationid=\"CR12\" class=\"CitationRef\"\u003e12\u003c/span\u003e, \u003cspan citationid=\"CR31\" class=\"CitationRef\"\u003e31\u003c/span\u003e]. For diagnosis of obstructive uropathy, the area under the curve for RTT was found to be 0.9, while the diagnostic accuracy was 0.69\u0026ndash;0.72. While RTT is increasingly recognized as a valuable quantitative parameter, the literature remains insufficient. There is a distinct lack of studies comparing scintigraphy with parameters such as mean transit time and calisial transit time. Due to the lack of comparative publications evaluating these metrics and the lack of sufficient data on RTT values, we chose to focus on RTT in our preliminary study for prediction of obstruction. Conducting further comparative studies that include quantitative parameters is crucial for advancing our understanding. Furthermore, emerging data on the SRF parameter have shown promising correlation with scintigraphy. The location and severity of obstruction are complex and diverse, further highlighting the need for comprehensive studies that account for these differences and effectively categorize them.\u003c/p\u003e\u003cp\u003eOur study has some limitations. First, bladder catheterization was not performed immediately before the MRU. Although we advised toilet-trained children to urinate before the dynamic examination, a full bladder could decrease urine flow. This may have resulted in reduced excretion and could mimic an obstruction. In addition, because the MRU and scintigraphy examinations were evaluated within the scope of a retrospective study, the examinations were not performed simultaneously. Furthermore, we did not precisely categorize the patient group according to the degree and level of obstruction and dilatation. Multiple subdivisions requires a large sample size. To significantly enrich the literature, future research should include several subgroups along with preoperative and postoperative comparisons, as well as the analysis of quantitative parameters along with scintigraphy. This would provide a more comprehensive understanding of the outcomes.\u003c/p\u003e"},{"header":"Conclusion","content":"\u003cp\u003eThere is a significant positive correlation between SRF values obtained via MRU and MAG3 scintigraphy. RTT values obtained from MRU offer valuable diagnostic accuracy for prediction of urinary obstruction when compared with T1/2 obtained from MAG3 scintigraphy. Thus, dynamic contrast enhanced MRU-based quantitative results are helpful in determining functional status of kidney.\u003c/p\u003e"},{"header":"Declarations","content":"\u003cp\u003e\u003cstrong\u003e\u003cb\u003eEthical approval\u003c/b\u003e:\u003c/strong\u003e\u003cp\u003e The study was approved by the Ethics Committee of the Istanbul Faculty of Medicine (Date:10/12/2021, File Number: 22) in compliance with the Helsinki Declaration.\u003c/p\u003e\u003c/p\u003e\u003cp\u003e\u003ch2\u003eCompeting Interests:\u003c/h2\u003e\u003cp\u003eThe authors have no relevant financial or non-financial interests to disclose.\u003c/p\u003e\u003c/p\u003e\u003ch2\u003eFunding:\u003c/h2\u003e\u003cp\u003eThe authors have declared that the study was conducted without the receipt of any financial support.\u003c/p\u003e\u003ch2\u003eAvailability of Data and materials:\u003c/h2\u003e\u003cp\u003eData generated or analyzed during the current study are available from the corresponding author upon reasonable request.\u003c/p\u003e"},{"header":"References","content":"\u003col\u003e\u003cli\u003e\u003cspan\u003eDickerson EC, Dillman JR, Smith EA, DiPietro MA, Lebowitz RL, Darge K (2015) Pediatric MR Urography: Indications, Techniques, and Approach to Review. Radiographics 35(4):1208\u0026ndash;1230\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eOtero HJ, Elsingergy MM, Back SJ (2022) Magnetic resonance urography: a practical approach to preparation, protocol and interpretation. Pediatr Radiol\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eMcLean RH, Gearhart JP, Jeffs R (1988) Neonatal obstructive uropathy. Pediatr Nephrol 2(1):48\u0026ndash;55\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eMendichovszky I, Solar BT, Smeulders N, Easty M, Biassoni L (2017) Nuclear Medicine in Pediatric Nephro-Urology: An Overview. Semin Nucl Med 2017;47(3):204\u0026thinsp;\u0026ndash;\u0026thinsp;28\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eDamasio MB, Bodria M, Dolores M, Durand E, Sertorio F, Wong MCY et al (2019) Comparative Study Between Functional MR Urography and Renal Scintigraphy to Evaluate Drainage Curves and Split Renal Function in Children With Congenital Anomalies of Kidney and Urinary Tract (CAKUT). Front Pediatr 7:527\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eKhrichenko D, Darge K (2010) Functional analysis in MR urography - made simple. Pediatr Radiol 40(2):182\u0026ndash;199\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eKatzberg RW, Buonocore MH, Ivanovic M, Pellot-Barakat C, Ryan JM, Whang K et al (2001) Functional, dynamic, and anatomic MR urography: feasibility and preliminary findings. Acad Radiol 8(11):1083\u0026ndash;1099\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eVivier PH, Dolores M, Taylor M, Elbaz F, Liard A, Dacher JN (2010) MR urography in children. Part 1: how we do the F0 technique. Pediatr Radiol 40(5):732\u0026ndash;738\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eVivier PH, Dolores M, Taylor M, Dacher JN (2010) MR urography in children. Part 2: how to use ImageJ MR urography processing software. Pediatr Radiol 40(5):739\u0026ndash;746\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eBoss A, Martirosian P, Fuchs J, Obermayer F, Tsiflikas I, Schick F et al (2014) Dynamic MR urography in children with uropathic disease with a combined 2D and 3D acquisition protocol\u0026ndash;comparison with MAG3 scintigraphy. Br J Radiol 87(1044):20140426\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eGrattan-Smith JD, Chow J, Kurugol S, Jones RA (2022) Quantitative renal magnetic resonance imaging: magnetic resonance urography. Pediatr Radiol 52(2):228\u0026ndash;248\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eJones RA, Perez-Brayfield MR, Kirsch AJ, Grattan-Smith JD (2004) Renal transit time with MR urography in children. Radiology 233(1):41\u0026ndash;50\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003ePrigent A, Cosgriff P, Gates GF, Granerus G, Fine EJ, Itoh K et al (1999) Consensus report on quality control of quantitative measurements of renal function obtained from the renogram: International Consensus Committee from the Scientific Committee of Radionuclides in Nephrourology. Semin Nucl Med 29(2):146\u0026ndash;159\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eRodigas J, Kirsch H, John U, Seifert P, Winkens T, Stenzel M et al (2018) Static and Functional MR Urography to Assess Congenital Anomalies of the Kidney and Urinary Tract in Infants and Children: Comparison With MAG3 Renal Scintigraphy and Sonography. AJR Am J Roentgenol 211(1):193\u0026ndash;203\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eShi W, Liang X, Wu N, Zhang H, Yuan X, Tan Y (2020) Assessment of Split Renal Function Using a Combination of Contrast-Enhanced CT and Serum Creatinine Values for Glomerular Filtration Rate Estimation. AJR Am J Roentgenol 215(1):142\u0026ndash;147\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eYou S, Ma X, Zhang C, Li Q, Shi W, Zhang J et al (2018) Determination of single-kidney glomerular filtration rate (GFR) with CT urography versus renal dynamic imaging Gates method. Eur Radiol 28(3):1077\u0026ndash;1084\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eYuan X, Zhang J, Tang K, Quan C, Tian Y, Li H et al (2017) Determination of Glomerular Filtration Rate with CT Measurement of Renal Clearance of Iodinated Contrast Material versus (99m)Tc-DTPA Dynamic Imaging Gates Method: A Validation Study in Asymmetrical Renal Disease. Radiology 282(2):552\u0026ndash;560\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eRiccabona M, Avni FE, Dacher JN, Damasio MB, Darge K, Lobo ML et al (2010) ESPR uroradiology task force and ESUR paediatric working group: imaging and procedural recommendations in paediatric uroradiology, part III. Minutes of the ESPR uroradiology task force minisymposium on intravenous urography, uro-CT and MR-urography in childhood. Pediatr Radiol 40(7):1315-20\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eArlen AM, Kirsch AJ, Cuda SP, Little SB, Jones RA, Grattan-Smith JD et al (2014) Magnetic resonance urography for diagnosis of pediatric ureteral stricture. J Pediatr Urol 2014;10(5):792-8\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eDillman JR, Trout AT, Smith EA (2016) MR urography in children and adolescents: techniques and clinical applications. Abdom Radiol (NY) 41(6):1007\u0026ndash;1019\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eClaudon M, Durand E, Grenier N, Prigent A, Balvay D, Chaumet-Riffaud P et al (2014) Chronic urinary obstruction: evaluation of dynamic contrast-enhanced MR urography for measurement of split renal function. Radiology 273(3):801\u0026ndash;812\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eKrumm P, Hupka T, Hau\u0026szlig;mann F, Dittmann H, M\u0026uuml;hlbacher T, Nadalin S et al (2021) Contrast-enhanced MRI for simultaneous evaluation of renal morphology and split renal function in living kidney donor candidates. Eur J Radiol 142:109864\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eWang Y, He C, Lai S, Xu X, Cai X, Li J et al (2024) Integrated Diffusion Tensor Imaging and Renal Parenchymal Volume for Early Detection and Grading of Split Renal Functional Impairment in Lupus Nephritis. Acad Radiol 31(7):2827\u0026ndash;2837\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eHe K, Wan D, Li S, Yuan G, Gao M, Han Y et al (2024) Non-contrast-enhanced magnetic resonance urography for measuring split kidney function in pediatric patients with hydronephrosis: comparison with renal scintigraphy. Pediatr Nephrol 39(5):1447\u0026ndash;1457\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eSchulze-Zachau V, Winkel DJ, Kaul F, Demerath T, Potthast S, Heye TJ et al (2023) Estimation of differential renal function on routine abdominal imaging employing compressed-sensed contrast-enhanced MR: a feasibility study referenced against dynamic renal scintigraphy in patients with deteriorating renal retention parameters. Abdom Radiol (NY) 48(4):1329\u0026ndash;1339\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eDzananovic A, Begic A, Pokrajac D (2019) Evaluation of Congenital Hydronephrosis with Static and Dynamic Magnetic Resonance Urography in Comparation to Dynamic Renal Scintigraphy. Acta Inf Med 27(3):181\u0026ndash;185\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eGołuch M, Pytlewska A, Sarnecki J, Chodnicka P, Śliwińska A, Obrycki Ł et al (2024) Evaluation of differential renal function in children \u0026ndash; a comparative study between magnetic resonance urography and dynamic renal scintigraphy. BMC Pediatr 24(1):213\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eAl-Shaqsi Y, Peycelon M, Paye-Jaouen A, Carricaburu E, Tanase A, Grapin-Dagorno C et al (2024) Evaluating pediatric ureteropelvic junction obstruction: Dynamic magnetic resonance urography vs renal scintigraphy 99m-technetium mercaptoacetyltriglycine. World J Radiol 16(3):49\u0026ndash;57\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eHadjidekov G, Hadjidekova S, Tonchev Z, Bakalova R, Aoki I (2011) Assessing renal function in children with hydronephrosis - additional feature of MR urography. Radiol Oncol 45(4):248\u0026ndash;258\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eŚwiȩtoń D, Grzywińska M, Czarniak P, Gołȩbiewski A, Durawa A, Teodorczyk J et al (2022) The Emerging Role of MR Urography in Imaging Megaureters in Children. Front Pediatr 10:839128\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eViteri B, Calle-Toro JS, Ballester L, Darge K, Furth S, Khrichenko D et al (2021) Potential benefits of functional magnetic resonance urography (fMRU) over MAG3 renal scan in children with obstructive uropathy. J Pediatr Urol 17(5):659. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003ee1-.e7\u003c/span\u003e\u003cspan address=\"http://e1-.e7\" targettype=\"URL\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e\u003c/span\u003e\u003c/li\u003e\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":true,"isPdf":false,"isPdfUpToDate":true,"isWithdrawnOrRetracted":false,"journal":{"display":true,"email":"[email protected]","identity":"pediatric-nephrology","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"pnep","sideBox":"Learn more about [Pediatric Nephrology](http://link.springer.com/journal/467)","snPcode":"467","submissionUrl":"https://www.editorialmanager.com/pnep/default2.aspx","title":"Pediatric Nephrology","twitterHandle":"","acdcEnabled":true,"dfaEnabled":true,"editorialSystem":"em","reportingPortfolio":"Springer Hybrid","inReviewEnabled":true,"inReviewRevisionsEnabled":false},"keywords":"MR urography, MAG3 scintigraphy, renal function, children","lastPublishedDoi":"10.21203/rs.3.rs-7255640/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-7255640/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003cp\u003e\u003cstrong\u003ePurpose: \u003c/strong\u003eMR urography examinations allow the assessment of kidney functions through recently developed image post-processing techniques, in addition to providing detailed visualization of urinary system anatomy. MR urography and MAG3 scintigraphy were compared in terms of functional evaluation.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eMethods: \u003c/strong\u003eDynamic contrast-enhanced MR urography images of 90 children who had previously undergone MAG3 scintigraphy examinations were evaluated. Morphological parameters, volumetric split renal functions (SRF) and renal transit times (RTT) were calculated from the dynamic MR urography phases using the CHOP-fMRU software for a total of 76 patients. Results were compared with the half-time (T1/2) and SRF values obtained from MAG3 scintigraphy. Student's t-test and Mann-Whitney U test were used to compare quantitative variables, and correlation analysis was performed.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eResults: \u003c/strong\u003eThe ages of the patients included in the study ranged from 1 to 216 months, with a mean age of 76.82 ± 62.59 months. Statistically significant positive correlations (r \u0026gt; 0.9, p =0.001) were found between SRFs of the right and left kidneys, measured by MR urography and scintigraphy. When the agreement between RTT and radionuclide half-life was evaluated, the sensitivity, specificity, positive and negative predictive values ​​of RTT for urinary obstruction were 65%, 83%, 90% and 53%, respectively.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eConclusion: \u003c/strong\u003eMR urography based SRF calculations could to be an invaluable tool in the assessment of separate renal functions. Its high positive predictive value in detecting obstruction rivals that of MAG3 scintigraphy. Despite the lack of extensive comparative data, the potential benefits of MR urography justify the need for further studies.\u003c/p\u003e","manuscriptTitle":"Prediction of Split Renal Function and Obstruction with MR Urography in Comparison with Dynamic Renal Scintigraphy","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2025-08-06 09:36:11","doi":"10.21203/rs.3.rs-7255640/v1","editorialEvents":[{"type":"communityComments","content":0},{"type":"decision","content":"Major Revisions Needed","date":"2025-09-22T03:26:11+00:00","index":"","fulltext":""},{"type":"reviewerAgreed","content":"","date":"2025-09-01T16:23:10+00:00","index":0,"fulltext":""},{"type":"reviewersInvited","content":"","date":"2025-07-31T17:46:18+00:00","index":"","fulltext":""},{"type":"editorAssigned","content":"","date":"2025-07-31T14:47:31+00:00","index":"","fulltext":""},{"type":"submitted","content":"Pediatric Nephrology","date":"2025-07-30T14:26:01+00:00","index":"","fulltext":""}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"pediatric-nephrology","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"pnep","sideBox":"Learn more about [Pediatric Nephrology](http://link.springer.com/journal/467)","snPcode":"467","submissionUrl":"https://www.editorialmanager.com/pnep/default2.aspx","title":"Pediatric Nephrology","twitterHandle":"","acdcEnabled":true,"dfaEnabled":true,"editorialSystem":"em","reportingPortfolio":"Springer Hybrid","inReviewEnabled":true,"inReviewRevisionsEnabled":false}}],"origin":"","ownerIdentity":"af353475-f0e5-4b9a-8f2d-fd19057ca336","owner":[],"postedDate":"August 6th, 2025","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"published-in-journal","subjectAreas":[],"tags":[],"updatedAt":"2026-02-23T16:03:21+00:00","versionOfRecord":{"articleIdentity":"rs-7255640","link":"https://doi.org/10.1007/s00467-026-07211-y","journal":{"identity":"pediatric-nephrology","isVorOnly":false,"title":"Pediatric Nephrology"},"publishedOn":"2026-02-17 15:58:24","publishedOnDateReadable":"February 17th, 2026"},"versionCreatedAt":"2025-08-06 09:36:11","video":"","vorDoi":"10.1007/s00467-026-07211-y","vorDoiUrl":"https://doi.org/10.1007/s00467-026-07211-y","workflowStages":[]},"version":"v1","identity":"rs-7255640","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-7255640","identity":"rs-7255640","version":["v1"]},"buildId":"8U1c8b4HqxoKbykW_rLl7","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}