Bladder Volume Research Articles

Dosimetric Impact of Intrafraction Prostate Motion and Interfraction Anatomical Changes in Dose-Escalated Linac-Based SBRT

The aim of this study was to investigate the impact of intrafraction prostate motion and interfraction anatomical changes on dose metrics and the effect of beam gating and motion correction in dose-escalated Linac-based SBRT. Thirteen patients (56 fractions) with organ-confined prostate cancer underwent dose-escalated FFF-VMAT SBRT. Accurate patient setup was ensured by CBCT, and real-time 3D prostate motion data were obtained using a novel electromagnetic tracking device. Treatment was interrupted when the signals exceeded a 2 mm threshold in any of the three spatial directions and couch position was corrected unless the offset was transient. Prostate trajectories with and without beam gating and motion correction events were reconstructed and analyzed. Rectum and bladder volumes on each daily CBCT were recorded and compared with volumes at simulation. The prostate motion observed for each fraction was incorporated into the patient original treatment plan with an isocenter shift method. Actually, delivered treatments were then obtained by recalculating the reconstructed motion-encoded plan on deformed CTs reflecting the patient CBCT-anatomy of the day. Non-gated treatments were also simulated using the prostate motion data assuming that no treatment interruptions have occurred. Treatment interruptions because of target motion trespassing the predefined threshold occurred in 25 fractions (45%). Rectum and bladder volume changes were relevant in most patients. The mean relative dose differences between actually delivered and planned treatments were -3.0% [-18.5 - 2.8] for CTV D99% and -2.6% [-17.8 - 1.0] for PTV D95% over all 56 fractions. However, the median cumulative CTV coverage with 93% of the prescribed dose turned out to be satisfactory. Urethra sparing was slightly degraded and a mean reduction of rectum and bladder dose was seen in all but two dose metrics: the maximum dose to rectum mucosa and the bladder D40%. Nevertheless, only 2 major deviations in rectum mucosa D0.035cc were observed at the end of the treatment. The greatest contribution to target missing and OARs doses came from the interfraction anatomical variations, while intrafraction prostate motion marginally contributed in gated treatments. In non-gated treatments, further deteriorations by 2.4 - 2.8% in minimum target coverage metrics and by 3.1 - 11.6% in bladder dose parameters would have occurred on average. The implemented motion management strategy and the strict patient preparation regimen, along with current PTV margins, robustness of original treatment plans, and fast FFF beam delivery, ensured no significant degradations of dose metrics due to both intrafraction motion and interfraction anatomical changes. Non-gated treatments would have more widely deteriorated the dosimetry of some individual fractions. Thus, continuous monitoring, beam gating and motion correction are recommended to safely deliver dose-escalated prostate SBRT.

Effectiveness of Bladder Filling Control during Online MR-Guided Adaptive Radiotherapy for Rectum Cancer

MR-guided adaptive radiotherapy (MRgART) treatment sessions at MR-Linac are time-consuming and changes in bladder filling during the session can impact the treatment dosimetry. In this work, we present the procedure implemented in the clinical workflow to stabilize bladder filling during the MR based adaptive radiotherapy sessions and evaluate its effectiveness and the resulting dosimetric impact on the adaptive plan. Twenty-five rectum cancer patients treated at 1.5T MR-Linac with a short course radiotherapy (25 Gy in 5 fractions of 5 Gy each) were included in this retrospective study. Patients were treated with the adapt-to-shape workflow consisting of a plan adaptation based on the MRI acquired in each session and optimized on the corresponding MR-based synthetic CT. Considering the significant interval time between the acquisition of the first daily MRI used for plan adaptation, and the beam delivery, a bladder catheter was used to stabilize the bladder filling; the procedure consists of emptying the bladder and refilling it with a well-known amount of physiological solution before each MRI acquisition. Two MRIs were acquired at each session: the first was used for plan adaptation and the second was acquired while approving the adapted plan, to be rigidly registered with the first to ensure the appropriateness of the isodoses on the ongoing delivery treatment. A total of 125 sessions and 250 MRI images and bladder contours were analyzed; for each fraction, the time interval between the first and second MRI and the corresponding bladder volumes were recorded; the consistency of bladder volumes and shapes along each online session was assessed with the dice similarity index (DSC) and Hausdorff distance (HD); the impact on plan dosimetry was evaluated by comparing target and bladder DVH cut off points of the plan on the two different MRI datasets. The time interval between the first and second MRI, averaged over the 125 sessions is 39.0 min, range (18.6-75.8) min. The changes in bladder volumes, DSC index, HD, and the differences between the bladder and target DVH cut-off points are shown in the table below. The DSC and HD are comparable to inter-observer variability in manual contour segmentation, with an average DSC of 0.91 and average HD of 2.13 mm; the average differences in bladder and target dosimetry remain under 0.63% and 0.10%, respectively. The use of a procedure in the clinical workflow of MRgART to stabilize the bladder filling throughout the online session may be helpful to guarantee the accuracy of the ongoing delivered treatment.

The Effect of Three Different Positioning Approaches for Prone Rectum Radiotherapy on Positioning Accuracy and Treatment Margins

The positioning accuracy of rectal radiotherapy patients was greatly affected by the immobilization gadget, breathing motion, bladder volume etc. Prone is one of the common treatment positions for rectum radiotherapy patients as it can displace the small bowels to reduce side effects. Our team would like to further enhance positioning accuracy by evaluating different positioning approaches. A total of 16 patients from each group were selected retrospectively. All patients fulfilled the bladder (±20% of CT-sim bladder volume) and bowel (empty bowel before the treatment) protocol before entering the treatment unit. Group A patients were positioned using commercial prone pelvic board (Orfit, Belgium) combined with thermoplastic membrane and skin markings; Group B patients were fixed with innovative prone pelvic board and vac-bag which positioned using skin markings. First three fractions and once weekly CBCT images were retrieved for data analysis. Group C patients were fixed the same as Group B and positioned using skin markings during the first fraction. New reference surface for the SGRT system (Vision RT Ltd, UK) was captured after CBCT shifts applied. The subsequent treatment, patient was aligned to ±0.1 cm and ±1.5° according to the new reference surface. CBCT shifts that were taken at fraction 2, 3, 4 and once weekly were recorded in 6 degrees of freedom. A total of 112 sets of data were retrieved from each groups respectively. The results were compared using nonparametric tests based on the normal distribution of the data. PTV margins (M) were calculated using the formula M = 2.5Σ+0.7σ. Positioning errors were shown in Table 1. The median positioning errors was statistically significant in lateral, vertical, roll and yaw for Group A and B. Whereas, Group C positioning errors was superior to Group B in all axes (p<0.05) except roll and yaw directions. The margins of Group A, B and C were 0.68cm, 1.17cm and 0.62cm; 0.56cm, 0.99cm and 0.75cm; 0.39cm, 0.36cm and 0.34cm in lateral, longitudinal and vertical directions. The results shown that Group B margins was smaller than Group A in lateral and longitudinal directions. Group C required the least margins. Positioning prone rectum patients using innovative pelvic board with the aid of surface guidance resulted in higher accuracy and smaller margins especially in longitudinal direction. Accurate positioning and good reproducibility could potentially reduce the margins from 6mm to 4mm for our prone rectum radiotherapy patients.

Towards Automated Dosimetric Analysis of the Bladder Trigone: Deep-Learning-Based Joint Segmentation and Landmark Localization

The bladder trigone dosimetry is hypothesized to have a stronger correlation with post-SBRT urinary toxicity than that of the entire bladder. However, the trigone tends to move significantly between simulation and daily treatment. Its small size, large daily motion, and proximity to the target lead to potentially consequential but unaccounted-for dosimetric uncertainties. Manual segmentation of the structure can be inconsistent and time-consuming, even with MR-guided RT. Here, we propose and demonstrate a deep-learning-based framework for joint segmentation and landmark localization to support deformable registration and comprehensive dosimetric analysis. A total of 30 patients were randomly selected for training, and 20 were held out for testing. Each patient had 1 simulation and 5 daily pre-treatment images obtained from a clinical 0.35T MR Linac. The trigone is defined as the triangular bladder section among three landmarks (2 ureteral orifices and the internal urethral orifice). In the manual contouring process, the 3 landmarks were identified first, followed by trigone segmentation. The proposed joint method uses a modified 3D nnU-Net with 2 decoders, one for segmentation and the other for landmark localization. The shared encoder is expected to extract features useful for both tasks. The joint framework was compared with a baseline method using two separate 3D nnU-Nets for landmark localization and trigone segmentation, respectively. Since the trigone is small (∼2% of the bladder volume), we further experimented with a second-stage prediction mimicking the human contouring process. The predicted landmarks from the first stage were used to crop the trigone region, and a second network was trained on cropped images. Evaluation metrics included the Dice score, 95% Hausdorff distance (HD95), and average surface distance (ASD) for segmentation, and Euclidean distance (ED) between the predicted and ground truth landmarks for localization. The quantification metrics are summarized in the table below. The joint approach shows similar Dice performance to the baseline method but markedly better HD95 by 13%. For landmark localization, the proposed method is similar to the baseline, but the integration of the segmentation task stabilizes the training process. The two-stage approach further improves HD95, ASD, and ED by 27%, 24%, and 19%. Combining segmentation and landmark localization exhibits a synergistic effect. The proposed two-stage approach provided additional improvement. Future studies will explore the deformable registration of the trigone based on the segmentation and landmark detection, as well as analyze cumulated dose distribution.

Late Urinary Toxicity and QoL with Curative Radiotherapy for High-Risk Prostate Cancer: Dose-Effect Relations in the POP-RT Randomized Phase III Trial

Whole pelvic radiotherapy (WPRT) showed better biochemical failure-free survival and metastasis-free survival than prostate-only radiotherapy (PORT) in the phase III randomized POP-RT trial for high and very high-risk prostate cancer, albeit with higher RTOG grade 2 late urinary toxicity. We report updated long term, symptom-wise comparison and dose-effect relations from this trial. Late urinary toxicity, and cumulative severity of each symptom over the follow-up period was graded using CTCAE v5.0. Grade 2+ toxicities were compared between the trial arms by chi square test. Bladder dosimetry in 5-Gy increments (V5, V10, V15...V65 Gy, V68 Gy) from the trial database of approved radiotherapy plans, was compared for each urinary symptom and overall late gr2+ toxicity by student t-test. Observed differences in dosimetric parameters were tested using multivariable logistic regression analysis, including age at diagnosis, known diabetes, tumor stage, trial arm, and prior transurethral resection of prostate (TURP). Urinary QOL scores were compared between arms using generalised linear mixed model. Combined late symptom-wise toxicity and dose-volume data were available for analysis for 193/224 patients. At a median follow-up of 75 months, cumulative CTCAE gr2+ late urinary toxicity remained higher with WPRT than PORT, though not statistically significant (36.5% vs 26.8%, p = 0.15). Grade 3 toxicity was low and similar in both arms. Symptom-wise cumulative rates showed no significant difference between arms (Table 1). Dosimetric comparison showed significantly higher bladder V5-V15 in patients with gr2+ toxicity over those with <gr2 urinary toxicity. On symptom-wise analysis, V5-V40 range was significantly higher for presence of dysuria, hematuria, and urgency. No significant differences were observed over higher dose range for any urinary symptom. On multivariable analysis, no significant association was identifiable between bladder dosimetry and urinary symptoms. Urinary QOL scores was similar between both the arms for all the symptoms. Compared to prostate-only radiotherapy, whole pelvic radiotherapy resulted similar Grade 3 urinary toxicity of about 5% with about 10% higher cumulative grade 2+ urinary toxicity over long term follow up. This difference was not reflected in patient-reported QOL. WPRT particularly increased urgency and hematuria. Larger bladder volume being irradiated with 5Gy to 15Gy dose range could contribute to increase in urinary symptoms.

Assessment of Bladder Filling Type on Radiation Dose to Organs at Risk in MR-Guided Intracavity Brachytherapy for Cervical Cancer

In this study, we evaluated whether the classification of bladder shape affects the absorbed dose (Gy) of OARs and its geometrical position to normal organs in MR-guided intracavitary brachytherapy (ICBT). In this study, 269 patients who underwent MR-guided ICBT for cervical cancer from 2016 to 2022 were included. The applicator-inserted bladder filling type (BFT) classification was divided into three types (tilted, curved, and other shapes: group E). The anatomical positional relationship between the uterus and its surroundings was measured on pre-MR images and ICBT simulation MR images. Spearman's rank correlation analysis was used for bladder volume and OAR dose according to BFT. Anatomical differences were analyzed by ANOVA by measuring the distance from the center to both bladder walls. In the correlation analysis considering the shape of the bladder, the tilted, curved, and group E had Spearman's ρ of 0.211; -0.323, 0.412; -0.307 and -0.035; -0.209 for maximum absorbed dose (D2cc) of bladder and small bowel, respectively. It was statistically significant in the tilted type and curved type. The average left and right bladder lengths differences of the tilted type were the highest at 8.47 cm and 7.11 cm, respectively. It was a statistically significant between bladder shape and the difference in left and right bladder lengths differences (p< 0.01). In this study, it was confirmed that bladder distension increased the maximum bladder dose (D2cc) and decreased the maximum bowel dose (D2cc) to the tilted type and curved type. In addition, if the left and right bladder lengths are measured in pre-MR, the degree of bladder distension can be evaluated in advance by checking the shape of the bladder in the case of the tilting type before ICBT. Based on these findings, a prospective study is needed to evaluate the effect of ICBT on cervical cancer treatment outcomes through bladder type classification.

Normal postvoid residual urine in healthy adults.

To establish a normal reference value of postvoid residual (PVR) urine volume in "healthy" adults. Adults were recruited to undergo uroflowmetry and PVR. Those with neurological disorders, malignancy, diabetes, known lower urinary tract dysfunction, and urinary tract infection within the previous 3 months, were excluded from the study. Constipation was defined as Rome IV ≥ 2. Of the 883 adults enrolled in this study, 194 (22.3%) did not complete the questionnaires or perform the uroflowmetry, 103 (11.7%) met ≥1 exclusion criteria and thus were excluded. In addition, 30 and 38 uroflowmetry were excluded due to artifacts and low bladder volume (BV) (<100 mL), respectively. Finally, 515 uroflowmetry and PVR data from adults aged 36-89 (mean: 59.0 ± 9.5) were examined. There was a significant nonlinear relationship between BV and PVR (p < 0.05), with PVR significantly increased when BV was around 528 mL. Women had lower PVR than men (p < 0.05). PVR also increased as the International Prostatic Symptom Score (IPSS) increased. PVR was unaffected by age and functional constipation. A multivariate analysis revealed that BV (p < 0.05) and IPSS (p < 0.05) had significant influence on PVR, but age, gender, and Rome IV score did not. The 90th and 95th percentiles of PVR for men were 73.2 mL (25% of BV) and 102.6 mL (30% of BV), respectively, while for women they were 60.5 mL (21% of BV) and 93.8 mL (27% of BV), respectively. Women had lower PVR than men. The 90th percentile or 95th percentile of normal adults' PVR may serve as the upper limit of normal PVR, and readings above this level may necessitate additional evaluation and treatment. Further studies are required to substantiate these recommendations.

Effects of comprehensive functional nursing on functional recovery and quality of life in patients with spinal cord injury.

This study evaluated the effects of comprehensive functional nursing on functional recovery and quality of life in patients with spinal cord injuries (SCIs). A total of 214 patients with SCIs treated in our hospital from October 2019 to October 2021 were included in the retrospective analysis and divided into a general care group (n = 107) and a comprehensive care group (n = 107), based on the care that they received. Patients in the general care group received general functional nursing, whereas those in the comprehensive care group received a comprehensive functional nursing intervention. The Rivermead Mobility Index (RMI), Barthel Index (BI), and Berg Balance Score (BBS) were used to evaluate patient neurobehavioral ability before and after nursing. Changes in cardiopulmonary function indexes, left ventricular end-diastolic dimension (LVEDD), left ventricular end-systolic dimension (LVESD), vital capacity (VC), forced expiratory volume in 1 second (FEV1), FEV1/FVC, and maximal voluntary ventilation (MVV) were measured before and after nursing. The number of micturition, maximum micturition volume, bladder volume, residual urine volume, and lower urinary tract symptom (LUTS) score were recorded, and the improvement in bladder function were measured before and after nursing. The Hamilton Anxiety Scale (HAMA) and Beck Depression Inventory (BDI) scores were used to evaluate patients' emotional state. After nursing, the RMI, BI, BBS score, FEV1, FEV1/FVC, MVV, maximum micturition volume, bladder volume, and SF-36 scores of the comprehensive care group were significantly higher than those of the general care group, and the LVEDD, LVESD, micturition time, residual urine volume, and LUTS, HAMA, and BDI scores of the comprehensive care group were significantly lower than those of the general care group. In patients with SCIs, comprehensive functional nursing can promote the recovery of neurocognition, bladder function, and cardiorespiratory function, and improve their quality of life. Comprehensive functional nursing is worthy of clinical application.

International Urogynecology consultation chapter 2 committee 3: the clinical evaluation of pelvic organ prolapse including investigations into associated morbidity/pelvic floor dysfunction

Introduction and hypothesisThis manuscript from Chapter 2 of the International Urogynecology Consultation (IUC) on Pelvic Organ Prolapse (POP) reviews the literature involving the clinical evaluation of a patient with POP and associated bladder and bowel dysfunction.MethodsAn international group of 11 clinicians performed a search of the literature using pre-specified search MESH terms in PubMed and Embase databases (January 2000 to August 2020). Publications were eliminated if not relevant to the clinical evaluation of patients or did not include clear definitions of POP. The titles and abstracts were reviewed using the Covidence database to determine whether they met the inclusion criteria. The manuscripts were reviewed for suitability using the Specialist Unit for Review Evidence checklists. The data from full-text manuscripts were extracted and then reviewed.ResultsThe search strategy found 11,242 abstracts, of which 220 articles were used to inform this narrative review. The main themes of this manuscript were the clinical examination, and the evaluation of comorbid conditions including the urinary tract (LUTS), gastrointestinal tract (GIT), pain, and sexual function. The physical examination of patients with pelvic organ prolapse (POP) should include a reproducible method of describing and quantifying the degree of POP and only the Pelvic Organ Quantification (POP-Q) system or the Simplified Pelvic Organ Prolapse Quantification (S-POP) system have enough reproducibility to be recommended. POP examination should be done with an empty bladder and patients can be supine but should be upright if the prolapse cannot be reproduced. No other parameters of the examination aid in describing and quantifying POP. Post-void residual urine volume >100 ml is commonly used to assess for voiding difficulty. Prolapse reduction can be used to predict the possibility of postoperative persistence of voiding difficulty. There is no benefit of urodynamic testing for assessment of detrusor overactivity as it does not change the management. In women with POP and stress urinary incontinence (SUI), the cough stress test should be performed with a bladder volume of at least 200 ml and with the prolapse reduced either with a speculum or by a pessary. The urodynamic assessment only changes management when SUI and voiding dysfunction co-exist. Demonstration of preoperative occult SUI has a positive predictive value for de novo SUI of 40% but most useful is its absence, which has a negative predictive value of 91%. The routine addition of radiographic or physiological testing of the GIT currently has no additional value for a physical examination. In subjects with GIT symptoms further radiological but not physiological testing appears to aid in diagnosing enteroceles, sigmoidoceles, and intussusception, but there are no data on how this affects outcomes. There were no articles in the search on the evaluation of the co-morbid conditions of pain or sexual dysfunction in women with POP.ConclusionsThe clinical pelvic examination remains the central tool for evaluation of POP and a system such as the POP-Q or S-POP should be used to describe and quantify. The value of investigation for urinary tract dysfunction was discussed and findings presented. The routine addition of GI radiographic or physiological testing is currently not recommended. There are no data on the role of the routine assessment of pain or sexual function, and this area needs more study. Imaging studies alone cannot replace clinical examination for the assessment of POP.

Quantitative assessment of adaptive radiotherapy for prostate cancer using deep learning: Bladder dose as a decision criterion.

Adaptive radiotherapy (ART) can incorporate anatomical variations in a reoptimized treatment plan for fractionated radiotherapy. An automatic solution to objectively determine whether ART should be performed immediately after the daily image acquisition is highly desirable. We investigate a quantitative criterion for whether ART should be performed in prostate cancer radiotherapy by synthesizing pseudo-CT (sCT) images and evaluating dosimetric impact on treatment planning using deep learning approaches. Planning CT (pCT) and daily cone-beam CT (CBCT) data sets of 74 patients are used to train (60 patients) and evaluate (14 patients) a cycle adversarial generative network (CycleGAN) that performs the task of synthesizing high-quality sCT from daily CBCT. Automatic delineation (AD) of the bladder is performed on the sCT using the U-net. The combination of sCT and AD allows us to perform dose calculations based on the up-to-date bladder anatomy to determine whether the original treatment plan (ori-plan) is still applicable. For positive cases that the patients' anatomical changes and the associated dose calculations warrant re-planning, we made rapid plan revisions (re-plan) based on the ori-plan. The mean absolute error within the region-of-interests (i.e., body, bladder, fat, muscle) between the sCT and pCT are 41.2, 25.1, 26.5, and 29.0HU, respectively. Taking the calculated results of pCT doses as the standard, for PTV, the gamma passing rates of sCT doses at 1mm/1%, 2mm/2% are 87.92%, 98.78%, respectively. The Dice coefficients of the AD-contours are 0.93 on pCT and 0.91 on sCT. According to the result of dose calculation, we found when the bladder volume underwent a substantial change (79.7%), the bladder dose is still within the safe limit, suggesting it is insufficient to solely use the bladder volume change as a criterion to determine whether adaptive treatment needs to be done. After AD-contours of the bladder using sCT, there are two cases whose bladder dose . For the two cases, we perform re-planning to reduce the bladder dose to , under the condition that the PTV meets the prescribed dose. We provide a dose accurate adaptive workflow for prostate cancer patients by using deep learning approaches, and implement ART that adapts to bladder dose. Of note, the specific replanning criterion for whether ART needs to be performed can adapt to different centers' choices based on their experience and daily observations.

263 the Minimum Acceptable Bladder Volume in Prostate Cancer Radiation Therapy with Vmat Delivery Technique

263 the Minimum Acceptable Bladder Volume in Prostate Cancer Radiation Therapy with Vmat Delivery Technique

Non-invasive bladder volume sensing via FMCW radar: Feasibility demonstration in simulated and ex-vivo bladder models

Non-invasive bladder volume sensing via FMCW radar: Feasibility demonstration in simulated and ex-vivo bladder models

Effectiveness of bladder filling control during online MR-guided adaptive radiotherapy for rectal cancer

BackgroundMagnetic resonance-guided adaptive radiotherapy (MRgART) treatment sessions at MR-Linac are time-consuming and changes in organs at risk volumes can impact the treatment dosimetry. This study aims to evaluate the feasibility to control bladder filling during the rectum MRgART online session and its effectiveness on plan dosimetry.MethodsA total of 109 online adaptive sessions of 24 rectum cancer patients treated at Unity 1.5 T MR-Linac with a short course radiotherapy (25 Gy, 5 Gy × 5) for whom the adaptive plan was optimized and recalculated online based on the daily magnetic resonance imaging (MRI) were analysed. Patients were fitted with a bladder catheter to control bladder filling; the bladder is emptied and then partially filled with a known amount of saline at the beginning and end of the online session. A first MRI ({mathrm{MRI}}_{mathrm{i}}) acquired at the beginning of the session was used for plan adaptation and the second ({mathrm{MRI}}_{mathrm{f}}) was acquired while approving the adapted plan and rigidly registered with the first to ensure the appropriateness of the isodoses on the ongoing delivery treatment. For each fraction, the time interval between the two MRIs and potential bladder changes were assessed with independent metrics, and the impact on the plan dosimetry was evaluated by comparing target and organs at risk dose volume histogram cut-off points of the plan adapted on {mathrm{MRI}}_{mathrm{i}} and recalculated on {mathrm{MRI}}_{mathrm{f}}.ResultsMedian bladder volume variations, DSC, and HD of 8.17%, 0.922, and 2.92 mm were registered within a median time of 38 min between {mathrm{MRI}}_{mathrm{i}} and {mathrm{MRI}}_{mathrm{f}}; dosimetric differences < 0.65% were registered for target coverage, and < 0.5% for bladder, small bowel and femoral heads constraints, with a p value > 0.05.ConclusionThe use of a bladder filling control procedure can help ensure the dosimetric accuracy of the online adapted treatment delivered.

Comparative Effectiveness of Two Models of Point-of-Care Ultrasound for Detection of Post-Void Residual Urine during Acute Ischemic Stroke: Preliminary Findings of Real-World Clinical Application.

We conducted a comparative study of two models of point-of-care ultrasound devices for measuring post-void residual urine (PVRU). We prospectively enrolled 55 stroke inpatients who underwent both real-time B-mode ultrasound (Device A) and automated three-dimensional (3D) scanning ultrasound (Device B), with a total of 108 measurements. The median PVRU volume of Device B was 40 mL larger than that of Device A. The PVRU difference between the devices was positively and linearly correlated with PVRU. The correlation of PVRU volume between the devices was strong, but the agreement level was only moderate. Measurement deviations were observed in 43 (40%) and 11 (10%) measurements with Device B and Device A, respectively. The PVRU volume was low in spherical bladder shapes but sequentially increased in triangular, undefined, ellipsoid, and cuboid bladder shapes. Further comparison of 60 sets of PVRU without measurement deviations revealed higher agreements between the devices at correction coefficients of 0.52, 0.66, and 0.81 for PVRU volumes of <100, 100-200, and >200 mL, respectively. The automated 3D scanning ultrasound is more convenient for learning and scanning, but it exhibits larger measurement deviations. Real-time B-mode ultrasound accurately visualizes the urinary bladder but tends to underestimate the urinary bladder when the PVRU volume is large. Hence, real-time B-mode ultrasound with automated PVRU-based adjustment of calculation formulas may be a better solution for estimating bladder volume.

Assessment of bladder filling during prostate cancer radiation therapy with ultrasound and cone-beam CT.

Prostate cancer patients undergoing external beam radiation therapy (EBRT) benefit from a full bladder to decrease bowel and bladder toxicity. Ultrasound may offer a proxy metric for evaluation, sparing CBCT dosing. Patients were prospectively enrolled pre-simulation from January 2017 to February 2018. Bladder volume was evaluated prior to RT using US daily and CBCT for three daily treatments and then weekly unless otherwise indicated. 29 patients completed median 40 days of RT, resulting in 478 CBCT and 1,099 US bladder volumes. 21 patients were treated to intact glands and 8 to the post-prostatectomy bed. Median patient age was 70 years. Bladder volume on CBCT and US positively correlated (r = 0.85), with average bladder volume for all patients of 162 mL versus 149 mL, respectively. Bladder volume during treatment was consistently lower than the volume at CT simulation (153 mL vs 194 mL, p<0.01) and progressively declined during treatment. Patients older than 70 years presented with lower average bladder volumes than those < 70 years (122 mL vs 208 mL, respectively, p<0.01). Patients with the highest agreement between CBCT and US (<10% variability) had higher average bladder volumes (192 mL vs 120 mL, p=0.01). US was found to be an accurate measure of bladder volume and may be used to monitor daily bladder volumes in patients being treated with radiation for prostate cancer.

Weakly supervised learning-based 3D bladder reconstruction from 2D ultrasound images for bladder volume measurement.

Accurate measurement of bladder volume is necessary to maintain the consistency of the patient's anatomy in radiation therapy for pelvic tumors. As the diversity of the bladder shape, traditional methods for bladder volume measurement from 2D ultrasound have been found to produce inaccurate results. To improve the accuracy of bladder volume measurement from 2D ultrasound images for patients with pelvic tumors. The bladder ultrasound images from 130 patients with pelvic cancer were collected retrospectively. All data were split into a training set (80 patients), a validation set (20 patients), and a test set (30 patients). A total of 12 transabdominal ultrasound images for one patient were captured by automatically rotating the ultrasonic probe with an angle step of 15°. An incomplete 3D ultrasound volume was synthesized by arranging these 2D ultrasound images in 3D space according to the acquisition angles. With this as input, a weakly supervised learning-based 3D bladder reconstruction neural network model was built to predict the complete 3D bladder. The key point is that we designed a novel loss function, including the supervised loss of bladder segmentation in the ultrasound images at known angles and the compactness loss of the 3D bladder. Bladder volume was calculated by counting the number of voxels belonging to the 3D bladder. The dice similarity coefficient (DSC) was used to evaluate the accuracy of bladder segmentation, and the relative standard deviation (RSD) was used to evaluate the calculation accuracy of bladder volume with that of computed tomography (CT) images as the gold standard. The results showed that the mean DSC was up to 0.94 and the mean absolute RSD can be reduced to 6.3% when using 12 ultrasound images of one patient. Further, the mean DSC also was up to 0.90 and the mean absolute RSD can be reduced to 9.0% even if only two ultrasound images were used (i.e., the angle step is 90°). Compared with the commercial algorithm in bladder scanners, which has a mean absolute RSD of 13.6%, our proposed method showed a considerably huge improvement. The proposed weakly supervised learning-based 3D bladder reconstruction method can greatly improve the accuracy of bladder volume measurement. It has great potential to be used in bladder volume measurement devices in the future.

Polychlorinated Biphenyls (PCBs) Impact Prostatic Collagen Density and Bladder Volume in Young Adult Mice Exposed during in Utero and Lactational Development.

Polychlorinated biphenyls (PCBs) are persistent organic pollutants linked to deleterious health outcomes, including voiding dysfunction in developmentally exposed mice. Changes in prostate volume and/or extracellular matrix composition are associated with voiding dysfunction in men and animal models. Whether PCB-induced changes in voiding function in male mice occur in part via alterations to the prostate or an alternate mechanism is unclear. Therefore, we tested whether developmental exposure to the MARBLES PCB mixture altered prostate morphology in young adult offspring. C57Bl/6J female mice were dosed daily with the MARBLES PCB mixture at 0, 0.1, 1 or 6 mg/kg/d for two weeks prior to mating and through gestation and lactation, offspring were collected at 6 weeks of age. Ventral prostate mass was decreased in the 1 mg/kg/d PCB group compared to other PCB groups. There were no PCB-induced changes in prostate smooth muscle thickness, apoptosis, proliferation, or testes mass. PCBs impacted the prostate extracellular matrix; anterior prostate collagen density was decreased in the 1 mg/kg/d PCB group compared to all other groups. Normalized bladder volume was increased in male and female offspring in the 6 mg/kg/d PCB group compared to control. No change in water consumption, bladder mass or bladder smooth muscle thickness accompanied changes in bladder volume. Urine and serum creatinine concentrations were elevated but only in male mice. Together, these results suggest that developmental exposure to PCBs can influence prostate wet weight and prostate/bladder morphology, but PCBs do not promote prostate enlargement. Whether these changes persist throughout adult life and how they contribute to voiding function in animal models and humans is of future interest.

Sonographic Prevalence of Lower Urinary Tract Infection among Out and in Patients in Biosensors Medical Diagnostics Wuse II Abuja Metropolis: A Case Study of Those Presented for Bladder Ultrasound

Introduction: Two hundred outpatients were recruited for the study only sixty-five (65) of them were used from those who presented for bladder ultrasound. Masmed F5 4D ultrasound machine with a curvilinear transducer at 3.5MHz of frequency was used for the study. Pre and post void urinary bladder volume, anterior and posterior bladder wall thickness measurements were made on 65 healthy asymptomatic outpatients. There was no statistically significant difference between anterior and posterior bladder wall thickness (P&gt;0.05) however there was a statistical significant difference between pre-void and post-void urine volume (P&lt;0.05). Females were more prevalent in the study population than males with higher bladder wall thickness (BWT) consistent with lower urinary tract infection, the sonographic prevalence of urinary bladder retention was 8(12.31%), consisting of a male (1.54%) and females 7(10.77%) In line with bladder outlet obstruction (BOO) assessed at 5% level of significance. The sonographic prevalence of lower urinary tract infection in Biosensors medical diagnostics Wuse ll Abuja was 32.5% when assessed at the 5% level of in-significance (P&gt;0.05), and it was most prevalent in individuals between the ages of 26 and 30. In Nigeria, it is advised that lower urinary tract infections should be diagnosed and treated early in both males and females.

Reflex voiding in rat occurs at consistent bladder volume regardless of pressure or infusion rate.

The central nervous system (CNS) regulates lower urinary tract reflexes using information from sensory afferents; however, the mechanisms of this process are not well known. Pressure and volume were measured at the onset of the guarding and micturition reflexes across a range of infusion rates to provide insight into what the CNS is gauging to activate reflexes. Female Sprague Dawley rats were anesthetized with urethane for open outlet cystometry. A set of 10 infusion rates (ranging 0.92-65.5 mL/h) were pseudo-randomly distributed across 30 single-fill cystometrograms. Bladder pressure and external urethral sphincter electromyography were used for the determination of the onset of the micturition and guarding reflexes, respectively. The bladder volume at the onset of both reflexes was estimated from the total infusion rate during a single fill. In response to many single-fill cystometrograms, there was an increased volume the bladder could store without a significant increase in pressure. Volume was adjusted for this effect for the analysis of how pressure and volume varied with infusion rate at the onset of the micturition and guarding reflexes. In 25 rats, the micturition reflex was evoked at similar volumes across all infusion rates, whereas the pressure at micturition reflex onset increased with increasing infusion rates. In 11 rats, the guarding reflex was evoked at similar pressures across infusion rates, but the volume decreased with increasing infusion rates. These results suggest that the CNS is interpreting volume from the bladder to activate the micturition reflex and pressure from the bladder to activate the guarding reflex.

Intermittent vs continuous catheterization for postpartum urinary retention: A multicenter randomized controlled trial

Postpartum urinary retention (PUR) is a common complication in the immediate postpartum period. Yet, there is no consensus regarding optimal management. To compare between two catheterization strategies for the treatment of PUR. A multi-center prospective randomized controlled trial was conducted at four university-affiliated medical centers between January 2020 and June 2022. Individuals with PUR (bladder volume>150 mL) up to 6 hours following vaginal or Cesarean delivery were randomly allocated to one of two protocols: intermittent catheterization (IC) every 6 h, up to 4 times, or continuous catheterization (CC) with an indwelling urinary catheter for 24 h. If PUR was not resolved after 24 hours, an indwelling catheter was inserted for an additional 24 h in both groups. The primary endpoint was the mean time to PUR resolution. The secondary endpoints included post-catheter urinary tract infection rate and length of hospital stay. Satisfaction rate was estimated using the Birth Satisfaction Scale (BSS-30) questionnaire. Following randomization, 73 individuals were allocated to the IC group and 74 to the CC group. Mean time to PUR resolution was significantly shorter in the IC compared with the CC group (10.2±11.8 h vs. 26.5±9.0 h, p<0.001), with 75% and 93% resolution rates after one and two catheterizations, respectively. The number of individuals who achieved resolution at 24 h was 72 (99%) and 67 (91%) in the IC and CC groups, respectively (p=0.043). The satisfaction rate was higher in all categories in the IC compared with the CC group (p<0.001). No intercohort differences were found in the urinary tract infection rates (p=0.89) or hospital stay length (p=0.58). Intermittent catheterization for urinary retention following delivery is associated with quicker PUR resolution and a higher satisfaction rate, compared with indwelling catheterization, without increasing complication rates.