Preoperative Bladder Scanning Can Predict Postoperative Urinary Retention Following Total Joint Arthroplasty.

BACKGROUND: As total joint arthroplasty (TJA) moves to the outpatient setting, it is becoming clear that postoperative urinary retention (POUR) is a potential impediment to same-day discharge. Although risk factors for POUR have been widely studied, the lack of their clinical utility warrants investigation of specific preoperative factors that can assist in surgical planning and patient optimization. The purpose of the current study was to determine whether preoperative symptom surveys and bladder scanning are useful tools in identifying POUR risk. METHODS: We performed a prospective analysis of patients undergoing total hip arthroplasty (THA) and total knee arthroplasty (TKA) at a high-volume orthopaedic hospital between December 1, 2020, and September 30, 2021. A total of 507 patients (324 female and 183 male) undergoing TJA completed the American Urological Association (AUA) symptom index preoperatively and then again at 14 and 64 days postoperatively. Post-void bladder scans were obtained in the immediate preoperative setting. POUR was defined as a bladder volume of >500 mL that required catheterization. Chi-square and quintile analysis were used to compare bladder scanning volumes, and Student t tests were used to compare AUA scores. RESULTS: The rate of POUR was 37% (66 female and 34 male) and 23% (37 female and 19 male) in the TKA and THA groups, respectively. Increasing post-void residual volume (PVRV) measured on preoperative bladder scanning was found to be predictive of POUR. Among the TKA cohort, younger age and lower body mass index were also associated with increased catheterization, although age was not statistically significant. The AUA symptom survey was not found to correlate with POUR in either population. CONCLUSIONS: There was a predictable and exponential increase in the rate of catheterization as preoperative PVRV increased from 50 to 200 mL. The AUA symptom score showed no utility in predicting POUR in our study population. We propose that preoperative bladder ultrasonography become standard practice in TJA, especially among patients scheduled for same-day discharge. LEVEL OF EVIDENCE: Prognostic Level II . See Instructions for Authors for a complete description of levels of evidence.

Association between diabetes mellitus and postoperative urinary retention after cerebral angiography.

AIMS: The aim of this study is to examine the association between diabetes mellitus and postoperative urinary retention on cerebral angiography (including intravascular interventional therapy). METHODS: We collected data on the demographic characteristics and comorbidities, imaging and routine laboratory data, surgical information, and medications of patients who underwent cerebral angiography. Multivariate logistic regression was used to explore the correlation between diabetes and the incidence of postoperative urinary retention. RESULTS: A total of 932 patients were included, with a mean age of 59.7 years (74.1% men). Postoperative urinary retention occurred in 40.8% of the diabetes mellitus group and 30.3% of the group without diabetes. Compared with the group without diabetes, those with diabetes were more likely to experience postoperative urinary retention. Patients with higher glycosylated hemoglobin A1c levels had a higher risk of developing postoperative urinary retention. CONCLUSIONS: Diabetes was independently linked to postoperative urinary retention following cerebral angiography and patients with glycosylated hemoglobin A1c levels > 6% were more likely to experience postoperative urinary retention. Therefore, clinically regulating blood glucose levels may help to reduce the likelihood of postoperative urinary retention after cerebral angiography.

Uso de la ultrasonografía en la evaluación de la retención urinaria en pacientes críticos / Use of ultrasonography in the evaluation of urinary retention in critically ill patients / Utilização da ultrassonografia na avaliação de retenção urinária em pacientes críticos

Objetivo: medir el volumen urinario por medio de la ecografía vesical, realizado por una enfermera en pacientes críticos, después de la retirada de la sonda urinaria permanente y verificar los factores relacionados en la retención urinaria. Método: estudio cuantitativo, observacional y transversal, realizado con 37 pacientes críticos de ambos sexos, mayores de 18 años, con retiro de catéter vesical permanente en las últimas 48 horas. Se utilizó un cuestionario con variables sociodemográficas y clínicas y el examen ecográfico. Se utilizó un cuestionario con variables sociodemográficas y clínicas y el examen ecográfico. Los datos fueron presentados a través de distribución de frecuencias, medidas de centralidad y variabilidad, asociación mediante la prueba exacta de Fisher y, para el análisis, regresión logística binomial múltiple. Resultados: de los 37 pacientes, en su mayoría fue de sexo masculino, con una edad média de 54,9 años. La medición del volumen urinario por ecografía osciló entre 332,3 y 950 ml, y el 40,54% de los pacientes presentó retención urinaria. La retención urinaria se asoció significativamente a la aparición de infección urinaria, estreñimiento intestinal y diuresis por rebosamiento espontáneo. Los pacientes con infección del tracto urinario tenían 7,4 veces más probabilidades de tener retención urinaria. Conclusión: la ecografía vesical fue eficaz para medir el volumen urinario después de retirar el catéter urinario permanente y puede contribuir a la detección de retención urinaria.

Objective: to measure urinary volume through bladder ultrasound, performed by a nurse in critically ill patients, after removal of the indwelling urinary catheter and to verify the related factors on urinary retention. Method: quantitative, observational and cross-sectional study, carried out with 37 critically ill patients of both sexes, over 18 years of age, with removal of indwelling urinary catheter in the last 48 hours. A questionnaire containing sociodemographic and clinical variables and an ultrasound examination were used. Data were presented through frequency distribution, centrality and variability measures, association using Fisher`s exact test and, for analysis multiple binomial logistic regression analysis. Results: the 37 patients were mostly male, with a mean age of 54.9 years. The measurement of urinary volume by ultrasound ranged from 332.3 to 950 ml, and 40.54% of patients had urinary retention. Urinary retention was significantly associated with the occurrence of urinary tract infection, intestinal constipation and spontaneous overflow diuresis. Patients with urinary tract infection were 7.4 times more likely to have urinary retention. Conclusion: bladder ultrasonography was effective in measuring urinary volume after removal of the indwelling urinary catheter and and may contribute to the detection of urinary retention.

Objetivo: mensurar o volume urinário por meio da ultrassonografia de bexiga, realizada por enfermeiro em pacientes críticos, após a remoção do cateter vesical de demora, e verificar os fatores relacionados na retenção urinária. Método: estudo quantitativo, observacional e transversal, realizado com 37 pacientes críticos de ambos os sexos, idade superior a 18 anos, com retirada de cateter vesical de demora nas últimas 48 horas. Foram utilizados um questionário contendo as variáveis sociodemográficas e clinicas e o exame de ultrassonografia. Os dados foram apresentados por meio da distribuição de frequência, medidas de centralidade e de variabilidade, associação pelo teste exato de Fisher e, para análise a regressão logística binomial múltipla. Resultados: dos 37 pacientes, a maioria era do sexo masculino, com média de idade de 54,9 anos. A mensuração do volume urinário pela ultrassonografia variou de 332,3 a 950 ml, sendo que 40,54% dos pacientes apresentaram retenção urinária. A retenção urinaria apresentou associação significativa para a ocorrência de infecção do trato urinário, constipação intestinal e diurese espontânea por transbordamento. Pacientes com infecção urinária tiveram 7,4 vezes mais chance de apresentar retenção urinária. Conclusão: ultrassonografia de bexiga foi eficaz para mensurar o volume urinário após a remoção do cateter vesical de demora e poderá contribuir na detecção da retenção urinária.

Use of ultrasonography in the evaluation of urinary retention in critically ill patients. / Uso de la ultrasonografía en la evaluación de la retención urinaria en pacientes críticos.

OBJECTIVE: to measure urinary volume through bladder ultrasound, performed by a nurse in critically ill patients, after removal of the indwelling urinary catheter and to verify the related factors on urinary retention. METHOD: quantitative, observational and cross-sectional study, carried out with 37 critically ill patients of both sexes, over 18 years of age, with removal of indwelling urinary catheter in the last 48 hours. A questionnaire containing sociodemographic and clinical variables and an ultrasound examination were used. Data were presented through frequency distribution, centrality and variability measures, association using Fisher`s exact test and, for analysis multiple binomial logistic regression analysis. RESULTS: the 37 patients were mostly male, with a mean age of 54.9 years. The measurement of urinary volume by ultrasound ranged from 332.3 to 950 ml, and 40.54% of patients had urinary retention. Urinary retention was significantly associated with the occurrence of urinary tract infection, intestinal constipation and spontaneous overflow diuresis. Patients with urinary tract infection were 7.4 times more likely to have urinary retention. CONCLUSION: bladder ultrasonography was effective in measuring urinary volume after removal of the indwelling urinary catheter and and may contribute to the detection of urinary retention. (1) Ultrasonography of the bladder showed an advantage for a better nursing diagnosis. (2) Critical patients had urinary retention after removal of urinary catheter. (3) Overflow incontinence was detected after removal of the urinary catheter. (4) Patients with urinary tract infection were 7.4 times more likely to have retention.

Memory-efficient low-compute segmentation algorithms for bladder-monitoring smart ultrasound devices.

Post-operative urinary retention is a medical condition where patients cannot urinate despite having a full bladder. Ultrasound imaging of the bladder is used to estimate urine volume for early diagnosis and management of urine retention. Moreover, the use of bladder ultrasound can reduce the need for an indwelling urinary catheter and the risk of catheter-associated urinary tract infection. Wearable ultrasound devices combined with machine-learning based bladder volume estimation algorithms reduce the burdens of nurses in hospital settings and improve outpatient care. However, existing algorithms are memory and computation intensive, thereby demanding the use of expensive GPUs. In this paper, we develop and validate a low-compute memory-efficient deep learning model for accurate bladder region segmentation and urine volume calculation. B-mode ultrasound bladder images of 360 patients were divided into training and validation sets; another 74 patients were used as the test dataset. Our 1-bit quantized models with 4-bits and 6-bits skip connections achieved an accuracy within [Formula: see text] and [Formula: see text], respectively, of a full precision state-of-the-art neural network (NN) without any floating-point operations and with an [Formula: see text] and [Formula: see text] reduction in memory requirements to fit under 150 kB. The means and standard deviations of the volume estimation errors, relative to estimates from ground-truth clinician annotations, were [Formula: see text] ml and [Formula: see text] ml, respectively. This lightweight NN can be easily integrated on the wearable ultrasound device for automated and continuous monitoring of urine volume. Our approach can potentially be extended to other clinical applications, such as monitoring blood pressure and fetal heart rate.

Postvoid residual bladder volume after uncomplicated vaginal delivery.

OBJECTIVE: To create a reference curve for postvoid residual volume (PVRV) in asymptomatic postpartum women who are at low risk of developing postpartum urinary retention (PUR), a well-known complication in the immediate postpartum period. METHODS: This is a prospective observational study measuring PVRV after uncomplicated vaginal delivery. PVRV was assessed by transabdominal ultrasound using a portable ultrasound scanner within the first 26 h after delivery (PVRV 1) and on the day of discharge (day 2 or 3 postpartum) (PVRV 2). A PVRV of 150 mL or more was defined as the cut-off value for covert PUR. RESULTS: The prevalence of covert PUR was 7.1%. Primiparity, duration of second stage, and obstetric injury were correlated with higher PVRV 1. The median PVRV 1 was 21 mL and PVRV 2 was 11 mL. The subgroup of nulliparous women had a significantly higher PVRV 1 compared with multiparous women. At discharge, the majority (99.1%) of women had a PVRV of less than 150 mL. CONCLUSION: Asymptomatic women were at low risk of developing PUR. However, women with a prolonged second stage may benefit from a routine postpartum assessment. Our results allow for a better understanding of PVRV in the early postpartum period.

Early prediction of urinary retention following radical hysterectomy by 18F-FDG PET/CT imaging.

BACKGROUND: Radical hysterectomy for early cervical cancer is associated with postoperative bladder dysfunction. Postoperative imaging by 18F-FDG PET/CT scanning is often performed to rule out recurrence. Since women are instructed to empty the bladder before imaging, we aim to study if scanned abnormal residual bladder volume is associated with future urinary symptoms. METHODS: Women who underwent radical hysterectomy for cervical cancer between July 2010 and January 2019 were included in the study. Multi-Modality Tumor Tracking® (MMTT) was used to measure residual urinary volume on 18F-FDG PET/CT scans before and after hysterectomy. Demographic, clinical parameters, and urinary tract signs and symptoms, were evaluated among the cohort. RESULTS: Overall, 64 patients were included. Among those, in 24 (38%) the bladder volume reached ≥150 cm3 on postoperative 18F-FDG PET/CT scans. Of these, 9 (37.5%) had voiding difficulties of some degree. In 3 (12.5%) women, the 18F-FDG PET/CT scan has preceded their complaints of voiding difficulties by 2-4 months. Of the 40 women (62%) whose postoperative bladder volumes were <150 cm3, only 1 (2.5%) had urinary retention. Rate of symptomatic voiding difficulties was higher in the post-void volume ≥150 cm3 group; 13 (54.1%) vs. 6 (15.0%), P<0.002, Odds Ratio 95% Confidence Interval 6.6 (2.0-21.8), P=0.001. CONCLUSIONS: Measuring bladder volume on postoperative 18F-FDG PET/CT may facilitate early identification of urinary retention, possibly enabling early treatment and possibly preventing complications.

A Cost-Effectiveness Analysis of Post-Void Residual Bladder Scan Thresholds in the Postoperative Setting.

INTRODUCTION AND HYPOTHESIS: To identify the optimal cost-effectiveness threshold of post-void residual (PVR) by bladder scan in postoperative urogynecologic patients. METHODS: A cost-effectiveness analysis was performed as a secondary analysis of a previously published study of patients undergoing urogynecologic procedures with planned voiding trials, setting thresholds for postoperative PVR bladder scan volumes at 100 ml, 150 ml, and 200 ml. Patient-based scenarios were modeled for ambulatory office or emergency department (ED) resource utilization and to determine the cost-effectiveness of each threshold. Costs were obtained from a southeastern academic medical center, only utilizing direct medical costs and hospital costs, not including societal costs. Quality-adjusted life years (QALY's) were used as health outcomes determining the incremental cost-effectiveness ratio (ICER). RESULTS: A total of 151 patients from the original study were included. A willingness to pay threshold of $100,000 per QALY was assumed. A PVR of 100 ml exceeded this at $373,824. A PVR threshold of 150 ml was dominant (-$1,211,716), while minimizing ED visits for postoperative urinary retention (POUR) and unnecessary clinic appointments. While a PVR of 200 ml appeared a cost-effective strategy (-$488,389), there was increased ED utilization and under-detection of postoperative urinary retention (POUR). CONCLUSION: A PVR threshold of 100 ml created a healthcare system burden due to increased office voiding trials. Both PVR thresholds of 150 ml and 200 ml were cost-effective strategies; however, ED utilization for POUR increased with 200 ml. Utilizing 150 ml as the PVR cut-off proved the most cost-effective strategy, avoiding POUR under-detection and undue health costs.

Three-dimensional bladder ultrasound to measure daily urinary bladder volume in hospitalized dogs.

BACKGROUND: Urinary bladder volume (UBV) and urine residual volume (URV) provide important information for hospitalized dogs and might allow recognition of urine retention. OBJECTIVE: Using 3-dimensional (3D) ultrasound to monitor daily URV is a safe and effective way to recognize urinary retention. ANIMALS: Twenty-five client-owned hospitalized dogs. METHODS: Prospective, observational study. UBV and URV were measured using 3D ultrasound daily at approximately the same time. UBV was measured, the dog was taken for a 5-minute controlled leash walk, then URV was estimated. Concurrent use of opioids, anesthetics, and fluids administered IV were recorded. RESULTS: Daily URVs were >0.4 mL/kg in 22 of 25 dogs on at least 1 day of hospitalization. Seventeen of 25 dogs had an abnormal URV at the time of discharge. Of 18 dogs that were anesthetized while hospitalized, 16 had a URV >0.4 mL/kg with a mean of 4.34 mL/kg (range, 0.5-13.4 mL/kg). No statistical difference in degree of URV was found based on the use of anesthesia, administration of fluids IV, or opioids. Weight was significantly associated with URV; dogs <10 kg had a higher URV per unit mass than dogs >10 kg (P = .001). CONCLUSIONS AND CLINICAL IMPORTANCE: Use of a 3D ultrasound device to measure daily UBV and URV in hospitalized dogs provides a safe estimate of bladder volume in real-time. Monitoring daily URV might help in early identification of patients that are retaining urine, thereby preventing potential adverse effects of urethral catheterization or prolonged urinary retention.

Bladder Scan Misleading a Vascular Emergency as Urinary Retention.

A middle-aged man arrives from a nursing facility to the emergency department with urinary retention and abdominal pain. A bladder scan was performed to identify the amount of urine in the bladder. Multiple attempts were made to place a urinary catheter without difficulty, but no urine was identified. When several attempts are made to insert a urinary catheter without success of urinary output, one must stop and rule out other causes. This case study outlines the etiology, diagnostics tests, and management of a patient with urinary retention.

Incidence of urinary retention and relations between patient's complaint, physical examination, and bladder ultrasound.

OBJECTIVE: To describe the frequency of urinary complaints, bladder globe, and need for bladder relief catheterization according to ultrasound; to investigate the relationship between the urinary volume estimated by ultrasound and the one drained in catheterization; and to describe the relationship of patient's complaints and detection of bladder globe with the diagnosis of urinary retention. METHOD: A cross-sectional study with clinical patients with suspected urinary retention in a tertiary hospital, conducted from February to September 2018. Urinary volume ≥500 mL in ultrasound was considered urinary retention. RESULTS: Two hundred and five evaluations were performed in 44 patients. Urinary retention was detected by ultrasound in 33.2% of the evaluations. There was a strong correlation between ultrasound and bladder catheterization. There was a higher frequency of identification of bladder globe in urinary volumes ≥300 mL. CONCLUSION: The incidence of urinary retention was higher when ultrasound was used for the diagnosis, when compared to patient's complaint and physical examination. Ultrasound showed to be accurate in establishing urinary volume.

Ovarian mucinous cystadenoma causing acute urinary retention.

Acute urinary retention rarely occurs in women, and is only infrequently caused by a pelvic mass. We describe a case of acute urinary retention caused by a large ovarian mucinous cystadenoma. Point of care ultrasound characterized and localized the lesion, while computerized tomography demonstrated the anatomic distortions resulting in urinary retention. The patient's symptoms resolved immediately following a laparoscopic right salpingo-oophorectomy with complete tumor removal.

Traumatismos uretrales en la infancia: presentación de dos casos / Anterior urethral trauma in childhood: presentation of two cases

INTRODUCCIÓN: La incidencia de traumatismos uretrales en niños es baja dado que su uretra es corta, móvil y está protegida en gran parte por el pubis. CASOS CLÍNICOS: Exponemos dos casos clínicos que ilustran la variedad de presentaciones de las lesiones en la uretra anterior. Primer niño con retención aguda de orina dos meses después de sufrir una caída a horcajadas. Posterior diagnóstico de estenosis uretral con cistouretrografía miccional seriada (CUMS). Segundo niño con incontinencia urinaria tras caída de un caballo. Hallazgo de divertículo uretral en CUMS y caracterización mediante ecografía. Ambos son tratados con cirugía diferida. COMENTARIOS: Es importante sospechar una lesión de uretra después de un traumatismo perineal. La CUMS es la prueba diagnóstica estándar. El tratamiento de elección implica uretroplastia diferida con buenos resultados, aunque presenta riesgo de incontinencia e impotencia

INTRODUCTION: The incidence of urethral trauma in children is low given that they have a short, mobile urethra, largely protected by the pubis. CLINICAL CASES: We describe two clinical cases illustrating the variety of presentations anterior urethral lesions can have. The first child had acute urinary retention two months after falling astride, with subsequent diagnosis of urethral stricture following serial voiding cystourethrogram (SVCU). The second child had urinary incontinence after falling off a horse. SVCU showed a urethral diverticulum, characterized through ultrasound imaging. Both were treated with deferred surgery. REMARKS: Urethral lesion should always be suspected after perineal trauma. SVCU is the gold standard diagnostic technique. Deferred urethroplasty is the treatment of choice, with good results, but there is a risk of incontinence and impotence

Implementation of a standardized voiding management protocol to reduce unnecessary re-catheterization - A quality improvement project.

OBJECTIVE: To design and implement a standardized postoperative voiding management protocol that accurately identifies patients with urinary retention and reduces unnecessary re-catheterization. METHODS: A postoperative voiding management protocol was designed and implemented in patients undergoing major, inpatient, non-radical abdominal surgery with a gynecologic oncologist. No patients had epidural catheters. The implemented quality improvement (QI) protocol included: 1) Foley removal at six hours postoperatively; 2) universal bladder scan after the first void; and 3) limiting re-catheterization to patients with bladder scan volumes >150 ml. A total of 96 patients post-protocol implementation were compared to 52 patients pre-protocol. Along with baseline demographic data and timing of catheter removal, we recorded the presence or absence of urinary retention and/or unnecessary re-catheterization and postoperative urinary tract infection rates. Fisher's exact test and student's t-tests were performed for comparisons. RESULTS: The overall rate of postoperative urinary retention was 21.6% (32/148). The new voiding management protocol reduced the rate of unnecessary re-catheterization by 90% (13.5% vs 2.1%, p = 0.01), without overlooking true urinary retention (23.1% vs 20.8%, p = 0.83). Additionally, there was a significant increase in hospital-defined early discharge prior to 11:00 AM (4.0% vs 22.0%, p = 0.022). There was no difference in the postoperative urinary tract infection rate between the groups (p = 1.00). Risk factors associated with urinary retention included older age (p < 0.01), use of medications with anticholinergic properties (p < 0.01), and preexisting urinary dysfunction (p < 0.01). CONCLUSIONS: Implementation of this new voiding management protocol reduced unnecessary re-catheterization, captured and treated true urinary retention, and facilitated early hospital discharge.

Impacto de la ecografía volumétrica portátil en el sondaje vesical por retención urinaria en una unidad de medicina interna / Impact of portable volumetric ultrasound on bladder catheterizations due to urinary retention in an internal medicine unit

OBJETIVO: Estimar el impacto que el uso de ecógrafo vesical tiene en los sondajes vesicales por sospecha de retención urinaria de una unidad de Medicina interna. METODOLOGÍA: Estudio de cohortes retrospectivas, comparando la cohorte expuesta a la disponibilidad del ecógrafo vesical, con la no expuesta el año previo. Se analizan todos los registros en la Historia Clínica Electrónica (HCE) de sondajes vesicales permanentes de corta duración en pacientes adultos que ingresaron en la unidad de hospitalización de Medicina Interna del Hospital Universitario Fundación Alcorcón (HUFA) durante los años 2015 y 2016. Se estima la frecuencia de retención urinaria como causa del sondaje después de la incorporación del dispositivo en la unidad y se compara con la frecuencia en sondajes durante el mismo periodo del año anterior en la misma unidad. Se estima el impacto que disponer de este dispositivo tiene en la frecuencia de retención urinaria como motivo del sondaje. RESULTADOS: Se incluyen 134 sondajes en 113 pacientes, 62 en el grupo sin ecógrafo y 72 en el grupo con ecógrafo. La frecuencia de sondajes por retención se reduce del 47.5% al 21.4% después de introducir el ecógrafo en la unidad. Esto supone una reducción del 50% (RR ajustado= 0.48; IC95%:0.27-0.84, p=0.01) en la frecuencia de sondaje vesical por sospecha de retención urinaria

AIM: To estimate the impact of the use of portable bladder volumetric ultrasound on bladder catheterization due to suspicion of urinary retention in an internal medicine unit. METHODOLOGY: Study of retrospective cohorts, comparing the cohort exposed to the availability of bladder ultrasound, with the not exposed the previous year. All records in the Electronic Medical Record (EHR) of short-term permanent bladder catheters in adult patients admitted to the Internal Medicine hospitalization unit of the University Hospital Fundación Alcorcón (HUFA) during the years 2015 and 2016 were analyzed. The urinary retention frequency is estimated as the cause of the catheterization after the device has been incorporated into the unit and compared with the frequency of catheterization during the same period of the previous year in the same unit. It is estimated that the impact of having this device on the urinary retention frequency is the reason for the catheterization. RESULTS: 134 catheters are included in 113 patients, 62 in the group without ultrasound and 72 in the group with ultrasound. The frequency of catheterizations due to retention is reduced from 47.5% to 21.4% after introducing the ultrasound unit into the unit. This represents a 50% reduction (adjusted RR=0.48; CI95%:0.27-0.84, p=0.01) in the frequency of urinary catheterization for suspected urinary retention

Accuracy of Bladder Scanner for the Assessment of Postvoid Residual Volumes in Women With Pelvic Organ Prolapse.

OBJECTIVES: The aim of the study was to evaluate the accuracy of the bladder scanner in assessing postvoid residual (PVR) volumes in patients with pelvic organ prolapse (POP). METHODS: We performed a prospective parallel cohort study evaluating the accuracy of the BVI 3000 bladder scanner in patients with POP. Patients with POP to the hymen were offered inclusion. Primary outcome was the absolute difference between bladder scanner and catheterization PVR. We also investigated the effect of prolapse stage on bladder scanner accuracy. A prevoid bladder volume was obtained by bladder scan. Subjects voided volume was then collected. A PVR was obtained by bladder scan, followed by a PVR by catheterization. Descriptive statistics, Wilcoxon signed-rank test, linear regression analysis, and sensitivity/specificity analysis were performed. RESULTS: We enrolled 87 subjects. There was a statistically significant difference between catheter and bladder scan PVR, with an absolute median difference of 20 mL (SD = 37.7), P < 0.001. Linear regression analysis showed a difference between mild and advanced prolapse groups. The regression coefficients of the mild prolapse group and advanced prolapse were 0.91 (confidence interval = 0.75-1.06) and 0.66 (confidence interval = 0.54-0. 78), P = 0.015, respectively, indicating a deterioration of accuracy of the bladder scanner for advanced prolapse. The sensitivity of the bladder scanner identifying catheterized PVR volumes less than 100 mL was 93.7%. For catheter PVRs greater than 100 mL, the specificity of the bladder scanner was 72.7%. CONCLUSIONS: Bladder scanner PVRs are less accurate in advanced prolapse, and PVRs of greater than 100 mL should be confirmed by catheterization.