Accuracy of post-void residual urine volume measurement using a portable ultrasound bladder scanner with real-time pre-scan imaging

Portable Ultrasound Bladder Volume Measurement Over Entire Volume Range Using a Deep Learning Artificial Intelligence Model in a Selected Cohort: A Proof of Principle Study

OBJECTIVE

We aimed to prospectively investigate whether bladder volume measured using deep learning artificial intelligence (AI) algorithms (AI-BV) is more accurate than that measured using conventional methods (C-BV) if using a portable ultrasound bladder scanner (PUBS).

PATIENTS AND METHODS

Patients who underwent filling cystometry because of lower urinary tract symptoms between January 2021 and July 2022 were enrolled. Every time the bladder was filled serially with normal saline from 0 mL to maximum cystometric capacity in 50 mL increments, C-BV was measured using PUBS. Ultrasound images obtained during this process were manually annotated to define the bladder contour, which was used to build a deep learning AI model. The true bladder volume (T-BV) for each bladder volume range was compared with C-BV and AI-BV for analysis.

RESULTS

We enrolled 250 patients (213 men and 37 women), and a deep learning AI model was established using 1912 bladder images. There was a significant difference between C-BV (205.5 ± 170.8 mL) and T-BV (190.5 ± 165.7 mL) (p = 0.001), but no significant difference between AI-BV (197.0 ± 161.1 mL) and T-BV (190.5 ± 165.7 mL) (p = 0.081). In bladder volume ranges of 101-150, 151-200, and 201-300 mL, there were significant differences in the percentage of volume differences between [C-BV and T-BV] and [AI-BV and T-BV] (p < 0.05), but no significant difference if converted to absolute values (p > 0.05). C-BV (R2 = 0.91, p < 0.001) and AI-BV (R2 = 0.90, p < 0.001) were highly correlated with T-BV. The mean difference between AI-BV and T-BV (6.5 ± 50.4) was significantly smaller than that between C-BV and T-BV (15.0 ± 50.9) (p = 0.001).

CONCLUSION

Following image pre-processing, deep learning AI-BV more accurately estimated true BV than conventional methods in this selected cohort on internal validation. Determination of the clinical relevance of these findings and performance in external cohorts requires further study.

TRIAL REGISTRATION

The clinical trial was conducted using an approved product for its approved indication, so approval from the Ministry of Food and Drug Safety (MFDS) was not required. Therefore, there is no clinical trial registration number.

Pre-therapeutical assessment of lower urinary tract symptoms in adult men: Systematic review and clinical practice guidelines

INTRODUCTION

The aim was to propose initial and pre-therapeutical assessment of lower urinary tract symptoms in adult men through a systematic review and clinical practice guidelines.

METHODS

These guidelines were based on a systematic review performed between January 2011 and November 2021 in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses criteria. The protocol was registered in the International Prospective Register of Systematic Reviews database (CRD42022336418). The recommendations and the methodology of elaboration were prospectively validated by the French Health Authority (Haute Autorité de santé [HAS]).

RESULTS

In total, 1662 publications were screened for eligibility and 311 met the inclusion criteria, 167 studies were retained among them 17 guidelines from French, European or International institutions. Perform on initial evaluation: identification of cardiovascular risk factors, metabolic syndrome, current medication, urinary and sexual symptoms (by structured interview or validated self-questionnaires), physical examination (lumbar fossa, pelvis, prostate, genitalia), urinalysis (dipstick or microscopy), abdominal ultrasound of the urinary tract (kidneys, bladder, prostate), post-void residual urine measurement (by ultrasound or automated measurement; under physiological conditions). Micturition flowmetry is recommended (except for general practitioners). Update and complete initial assessment before medication, interventional or surgical treatment if too old or incomplete. Perform a preoperative assessment (bleeding risk, infectious risk, geriatric risk). Urodynamic assessment, endorectal ultrasound and cystoscopy should not be systematically performed (only if additional information is needed). Perform urodynamics and urethrocystoscopy in case of failed interventional or surgical treatment. Following the initial workup, it is recommended to refer the patient to a urologist in case of: macroscopic hematuria, recurrent urinary tract infection or persistent perineal and/or suprapubic pain, persistent microscopic hematuria or leukocyturia in absence of urinary tract infection, predominant storage-phase symptoms, abnormal examination of the genitals or suspected prostate cancer, urinary retention, urinary tract stones, ureterohydronephrosis or morphological abnormalities of the prostate or the urinary tract.

CONCLUSION

These guidelines aimed to define the recommended investigation for LUTS in adult men at diagnosis, before medical treatment and before surgical and interventional treatments, in order to better personalize management and avoid unnecessary and/or invasive examinations.

Post-void residual measurement: A comprehensive review of the clinical relevance and precision of bladder scanner devices

OBJECTIVE

To evaluate the accuracy of bladder scanners in measuring bladder volume and to compare their precision.

METHOD

MEDLINE and Cochrane databases were searched from January 1, 1990 to December 30th, 2023. We selected studies assessing results of bladder volume measurement using bladder scanners, standard ultrasonography or bladder catheterization.

RESULTS

In total, 177 studies were screened, of which 22 were included in the final analysis. According to the literature, there is no clinically significant difference in the measurement of bladder volume using urethro-vesical catheterization, bladder scanner, or conventional ultrasound. Studies comparing different types of bladder scanners did not show any difference in accuracy.

CONCLUSIONS

Bladder scanners are precise tools to evaluate bladder volume in urological patients, applicable in daily practice. Knowledge of the patient's medical history is crucial to better interpret the measurement.

Recent developments in diagnostic ultrasound for lower urinary tract function

Ultrasonography (US) is an essential tool in the clinical management of lower urinary tract dysfunction (LUTD), including lower urinary tract symptoms, overactive bladder, and benign prostatic hyperplasia, in which prostatic volume and post-void residual volume are routinely used to evaluate the pathophysiological characteristics of afflicted patients. US can also be employed to diagnose hydronephrosis and bladder calculus as complications of severe LUTD. Moreover, US is essential for identifying pathophysiological characteristics and surgical indications, predicting disease development and drug efficacy, and monitoring bladder function improvement by means of such parameters as bladder wall thickness, prostatic urethral length, intravesical prostatic protrusion, and prostatic urethral angulation/angle. Herein, I narratively review the recent advances in US approaches for the management of LUTD, especially in adult males.

A Lightweight Deep Learning Network on a System-on-Chip for Wearable Ultrasound Bladder Volume Measurement Systems: Preliminary Study

Bladder volume assessments are crucial for managing urinary disorders. Ultrasound imaging (US) is a preferred noninvasive, cost-effective imaging modality for bladder observation and volume measurements. However, the high operator dependency of US is a major challenge due to the difficulty in evaluating ultrasound images without professional expertise. To address this issue, image-based automatic bladder volume estimation methods have been introduced, but most conventional methods require high-complexity computing resources that are not available in point-of-care (POC) settings. Therefore, in this study, a deep learning-based bladder volume measurement system was developed for POC settings using a lightweight convolutional neural network (CNN)-based segmentation model, which was optimized on a low-resource system-on-chip (SoC) to detect and segment the bladder region in ultrasound images in real time. The proposed model achieved high accuracy and robustness and can be executed on the low-resource SoC at 7.93 frames per second, which is 13.44 times faster than the frame rate of a conventional network with negligible accuracy drawbacks (0.004 of the Dice coefficient). The feasibility of the developed lightweight deep learning network was demonstrated using tissue-mimicking phantoms.

Can portable ultrasound bladder scanner be applied to young children less than three years old?

INTRODUCTION

The bladder scanner (BS), a portable ultrasound device specialized in bladder volume measurement, has been developed and applied to clinical assessment of postvoid residual urine, which is a requisite in evaluating patients with voiding dysfunction. However, experiences in the application of the BS to the pediatric population remain limited despite commonly encountered reluctance to catheterization. This prospective observational study aimed to evaluate the correlation and accuracy of the newly developed pediatric module of the BS (BioCon-900) in measuring bladder volume in children 0-6 years old.

MATERIALS AND METHODS

This study included 29 patients scheduled to undergo preventive untethering for their spinal dysraphism. When they undergo cystometry for the confirmation of normal neurologic function, bladder volume was measured by BS when recorded volume infusion reached each quartile of the age-adjusted estimated bladder capacity (EBC). The difference (bias) between measured and infused volume was expressed as a percentage of EBC (%EBC). The correlation coefficient and the Bland-Altman plot were obtained to determine the discriminating power and accuracy, respectively. The acceptable limit was set as 30%EBC.

RESULTS

A strong correlation between the measured and infused volume (r = 0.95, P < 0.001) was found for the entire age range. This excellent correlation remained comparable between children less than three years and the older ones. Bladder volume tended to be overestimated, and the mean bias was 33 ± 22.3%EBC, and it became higher with increasing quartiles. The accuracy was acceptable in all ranges of measurement in the older group and first and second quartiles in the younger one.

DISCUSSION

We have first evaluated the potential use of BS in 0-3 years old children and compared the results with 4-6-year-old children in whom the accuracy of BS has been demonstrated. The strong point of our study was the inclusion of data spanning all quartiles of bladder volume. The use of infused volume as reference enabled us to assess the accuracy in a more precise way than the use of ultrasound. Despite the good discriminating power, the accuracy was not acceptable in higher quartiles in the younger group. If the trend of overestimation especially higher volume, could be understood prior to measurement, it would be helpful to assume the real val.

CONCLUSIONS

The children's module in BS showed excellent discriminating power and generally acceptable accuracy in more than four-year-old children. This may lose accuracy in higher quartiles among less than three years old children.

Evaluation of a Point-of-Care Ultrasound Educational Program for Nurse Educators

BACKGROUND

The effectiveness of point-of-care ultrasound (POCUS) for nurses has been demonstrated; however, only a limited number of nurses have been trained to perform POCUS. This article reports on a POCUS train-the-trainer program for nurse educators that targets lower urinary track dysfunction.

METHOD

Nurse educators (n = 38) were invited to participate in a POCUS train-the-trainer program, which comprised an e-learning module and a hands-on seminar. Acquisition of knowledge and skills were assessed after the module and seminar, respectively.

RESULTS

Questions from the "Basic Knowledge of Ultrasonography" test were answered correctly at a rate of 93.0% (SD, 8.5%). Measured values of bladder urinary volume using ultrasonography were in close agreement with actual values. All of the participants indicated that the program covered the content necessary to use in practice.

CONCLUSION

The POCUS train-the-trainer program equips nurse educators with the knowledge and skills needed for training nurses at their institutions. [J Contin Educ Nurs. 2021;52(8):375-381.].

Comparative accuracy of the Lilium α-200 portable ultrasound bladder scanner and conventional transabdominal ultrasonography for postvoid residual urine volume measurement in association with the clinical factors involved in measurement errors

AIM

We examined the comparative accuracy of the portable ultrasound bladder scanner, Lilium α-200, and conventional ultrasonography (CUS) in bladder volume measurement. We also examined factors that could lead to measurement errors.

METHODS

Postvoid residual (PVR) volume was measured by Lilium α-200 and CUS with catheterized volume as a comparator in 224 consecutive men, of which 109 were also measured for the serially inflated bladder with saline. The measurement accuracy with respect to the actual volume was evaluated by calculating the error volume (EV), % error volume (%EV), and their absolute values. Absolute %EV of ≤20% was designated as nonerror. The measurement of prostate volume, abdominal thickness, and pelvimetry was performed on magnetic resonance images.

RESULTS

PVR volumes measured by CUS are better correlated with actual volumes (r = .779) than those of Lilium α-200 (r = .606). When the measurement accuracy was indicated by absolute values of EV and %EV, CUS provided a more accurate estimate (21 ± 21 ml, 60 ± 42%) than Lilium α-200 (32 ± 45 ml, 91 ± 142%). The frequency of error was significantly increased at lower bladder volumes. Overestimation was associated with larger prostate size for the Lilium α-200, while underestimation was associated with greater bladder flattening for both methods.

CONCLUSION

PVR volumes measured by Lilium α-200 were fairly correlated with actual volumes. However, their relative errors were too large to correctly predict the actual volume. Flattened bladder and a large prostate may hinder accurate measurements. Consequently, Lilium α-200 is not superior to CUS and its feasibility is limited to when the precise measurement is not required.

Advances in Ambulatory Urodynamics

PURPOSE OF REVIEW

This manuscript reviews recent technological advances in ambulatory urodynamics.

RECENT FINDINGS

Ambulatory urodynamics is currently recommended by the International Continence Society as a second-line diagnostic tool in patients with nondiagnostic traditional urodynamics. Novel techniques involving telemetric monitoring are in development, which utilize catheter-free wireless systems to address several recognized shortcomings of inoffice urodynamic studies. Current research in catheter-free bladder pressure measurements involves either an intravesical, intradetrusor, or transdetrusor approach. Real-time bladder volume estimation may be performed using ultrasonography, near-infrared spectroscopy, or bladder volume conductance measurement. Ambulatory urodynamics can measure bladder function in the "real world" setting, capturing physiological bladder filling and emptying and allowing patients to reproduce the activities that may trigger their symptoms. Telemetric devices being developed represent further advances in this field and focus upon improving diagnostic capabilities, evaluating patient response to treatment, and facilitating closed-loop bladder control with neuroprosthetic integration.

Effect of electroacupuncture on diabetic neurogenic bladder: A randomized controlled trial protocol

BACKGROUND

The most common and bothersome lower urinary tract complication of diabetes mellitus is diabetic neurogenic bladder (DNB). Acupuncture has certain advantages in treating bladder dysfunction including urinary retention and incontinence. Therefore, we think that electroacupuncture (EA) may be beneficial to DNB patients. However, it is not clear whether EA combined with basic western medicine could optimize the therapeutic effect for DNB.

METHOD/DESIGN

This is a sham-controlled, patient-blinded, pioneer randomized controlled trial (RCT). One hundred fifty eligible patients will be randomly divided into 3 groups: A. basic western medicine (BWC), B. EA with BWC, C. sham EA with BWC. EA treatment will be given twice a week for 12 weeks at bilateral BL23, BL32, BL33, and BL35. The BWC group will received Alpha-lipoic acid (ALA) and methylcobalamin (MC) treatment for 12 weeks, 2 treatment sessions per week. The primary outcome is scored by the 72-hour bladder diary (72h-BD). The secondary outcomes will be scored by the American Urological Association symptom index (AUA-SI), Post-void residual urine volume (PVR) and urodynamic tests. All the assessments will be conducted at baseline and the 12th weeks after the intervention starts. The follow-up assessments will be performed with 72h-BD and AUA-SI in the 4th, 12th, and 24th weeks after intervention ends.

DISCUSSION

This trial protocol provides an example of the clinical application acupuncture treatment in the management of DNB. This RCT will provide us information on the effect of treating DNB patients with only acupuncture, western medicine therapy (ALA + MC) as well as the combination of both. The additive effect or synergistic effect of acupuncture and basic western medicine will then be analyzed.

TRIAL REGISTRATION

Chinese Clinical Trial Registry, ChiCTR2000030421.

Motor, cognitive and mobility deficits in 1000 geriatric patients: protocol of a quantitative observational study before and after routine clinical geriatric treatment - the ComOn-study

BACKGROUND

Motor and cognitive deficits and consequently mobility problems are common in geriatric patients. The currently available methods for diagnosis and for the evaluation of treatment in this vulnerable cohort are limited. The aims of the ComOn (COgnitive and Motor interactions in the Older populatioN) study are (i) to define quantitative markers with clinical relevance for motor and cognitive deficits, (ii) to investigate the interaction between both motor and cognitive deficits and (iii) to assess health status as well as treatment outcome of 1000 geriatric inpatients in hospitals of Kiel (Germany), Brescia (Italy), Porto (Portugal), Curitiba (Brazil) and Bochum (Germany).

METHODS

This is a prospective, explorative observational multi-center study. In addition to the comprehensive geriatric assessment, quantitative measures of reduced mobility and motor and cognitive deficits are performed before and after a two week's inpatient stay. Components of the assessment are mobile technology-based assessments of gait, balance and transfer performance, neuropsychological tests, frailty, sarcopenia, autonomic dysfunction and sensation, and questionnaires to assess behavioral deficits, activities of daily living, quality of life, fear of falling and dysphagia. Structural MRI and an unsupervised 24/7 home assessment of mobility are performed in a subgroup of participants. The study will also investigate the minimal clinically relevant change of the investigated parameters.

DISCUSSION

This study will help form a better understanding of symptoms and their complex interactions and treatment effects in a large geriatric cohort.

Imaging Modalities in Genitourinary Emergencies

Emergency physicians rely on a multitude of different imaging modalities in the diagnosis of genitourinary emergencies. There are many considerations to be taken into account when deciding which imaging modality should be used first, as oftentimes several diagnostic tools can be used for the same pathologic condition. These factors include radiation exposure, sensitivity, specificity, age of patient, availability of resources, cost, and timeliness of completion. In this review, the strengths and weaknesses of different imaging tools in the evaluation of genitourinary emergencies are discussed.

Development and evaluation of automated ultrasonographic detection of bladder diameter for estimation of bladder urine volume

Bladder urine volume has been estimated using an ellipsoid method based on triaxial measurements of the bladder extrapolated from two-dimensional ultrasound images. This study aimed to automate this process and to determine the accuracy of the automated estimation method for normal and small amounts of urine. A training set of 81 pairs of transverse and longitudinal ultrasound images were collected from healthy volunteers on a tablet-type ultrasound device, and an automatic detection tool was developed using them. The tool was evaluated using paired transverse/longitudinal ultrasound images from 27 other healthy volunteers. After imaging, the participants voided and their urine volume was measured. For determining accuracy, regression coefficients were calculated between estimated bladder volume and urine volume. Further, sensitivity and specificity for 50 and 100 ml bladder volume thresholds were evaluated. Data from 50 procedures were included. The regression coefficient was very similar between the automatic estimation (β = 0.99, R2 = 0.96) and manual estimation (β = 1.05, R2 = 0.97) methods. The sensitivity and specificity of the automatic estimation method were 88.5% and 100.0%, respectively, for 100 ml and were 94.1% and 100.0%, respectively, for 50 ml. The newly-developed automated tool accurately and reliably estimated bladder volume at two different volume thresholds of approximately 50 ml and 100 ml.

False positive bladder scan in ascites with anuria

Urinary retention is commonly diagnosed based on history and examination along with bedside bladder scan. However, in patients where clinical examination is unreliable (patients with obesity, anasarca, and ascites) and diagnosis is uncertain, the bladder scan findings should be interpreted with caution and definitive imaging is mandatory before further intervention is instituted.

Ambulatory urodynamic monitoring: state of the art and future directions

Urodynamic studies are a key component of the clinical evaluation of lower urinary tract dysfunction and include filling cystometry, pressure-flow studies, uroflowmetry, urethral function tests and electromyography. However, pitfalls of traditional urodynamics include physical and emotional discomfort, artificial test conditions with catheters and rapid retrograde filling of the bladder, which result in variable diagnostic accuracy. Ambulatory urodynamic monitoring (AUM) uses physiological anterograde filling and, therefore, offers a longer and more physiologically relevant evaluation. However, AUM methods rely on traditional catheters and pressure transducers and do not measure volume continuously, which is required to provide context for pressure changes. Novel telemetric AUM (TAUM) methods that use wireless, catheter-free, battery-powered devices to monitor bladder pressure and volume while patients carry out their daily activities are currently being investigated. TAUM devices under current development are innovating in the areas of remote monitoring, rechargeable energy sources, device deployment and retrieval and materials engineering to provide increased diagnostic accuracy and improved comfort for patients with incontinence or voiding dysfunction. These devices hold promise for improving the diagnosis and management of patients with lower urinary tract disorders.

The Accuracy of Portable Ultrasound Bladder Scanner Measurements of Postvoid Residual Volume in Women With Pelvic Organ Prolapse

The purpose of this study was to evaluate the accuracy of portable bladder scanner postvoid residual (PVR) volume measurements in patients with pelvic organ prolapse. A secondary goal was to determine whether covariates such as bladder volume and stage of prolapse affect bladder scanner accuracy.

Portable Bladder Ultrasound Reduces Incidence of Urinary Tract Infection and Shortens Hospital Length of Stay in Patients With Acute Ischemic Stroke

BACKGROUND

Urinary tract infection (UTI) during acute ischemic stroke is associated with a longer hospital length of stay and unfavorable functional outcomes.

OBJECTIVE

We investigated the benefits of portable bladder ultrasound (PBU) scanning during acute ischemic stroke.

METHODS

We retrospectively reviewed patients with acute ischemic stroke from January 2011 to February 2017. Patients were divided into group 1 (PBU not available) and group 2 (PBU available), before or after the split date, April 9, 2014. Portable bladder ultrasound scanning was conducted by nurses to measure postvoid residual urine volume in patients with impaired consciousness and/or dependent ambulation.

RESULTS

In total, 1928 patients were enrolled, of whom 109 (5.7%) had UTI and 901 (46.7%) experienced unfavorable outcomes (modified Rankin scale score ≥ 3). Multivariate analysis revealed that factors that influenced UTI were age of 75 years or older, female gender, initial total National Institutes of Health Stroke Scale (NIHSS) score of 5 or higher, initial NIHSS conscious score of 1 or higher, initial NIHSS leg score of 2 or higher, and urinary catheterization. Factors influencing unfavorable outcomes were similar to those influencing UTI but further comprised UTI. C-statistic for UTI detection was 0.864 for model fitting, including significant factors in logistic regression. Compared with group 1, group 2 had a higher incidence of urinary catheterization (13.1% vs 8.2%), a lower incidence of UTI (4.0% vs 6.9%), and a shorter length of stay (11.9 vs 13.6 days).

CONCLUSIONS

Portable bladder ultrasound scanning reduced the incidence of UTI and shortened length of stay. We suggest routine PBU procedures for patients with acute ischemic stroke who fulfill the AGN3 criteria for a high risk of UTI.

Discrepancies in measuring bladder volumes with bedside ultrasound and bladder scanning in the intensive care unit: A pilot study

Objective

Intensive care unit patients are at risk for catheter-associated urinary tract infection. Earlier removal of catheters may be possible with accurate measurement of bladder volume. The purpose was to compare measured bladder volumes with bedside ultrasound, bladder scanner, and urine volume.

Design

Prospective correlational descriptive study.

Setting

Surgical/trauma intensive care unit and medical intensive care unit.

Patients

Renal dialysis patients with less than 100 ml of urine in 24 h prior to urinary catheter removal and patients with suspected catheter obstruction.

Measurements and main results

A physician trained in ultrasound and an advanced practice registered nurse trained in bladder scanning measured bladder volume; each blinded to the other's measurement. Device used first (ultrasound or bladder scanner) alternated daily. The intensive care unit team determined need for intermittent catheterization or treatment for suspected obstruction. Fifty-one measurements from 13 patients were obtained with results reported in milliliters. Ultrasound measurements were a mean volume of 72.1 ± 127 (range: 1.7-666) and the bladder scanner measurements were 117 ± 131 (0-529). On six occasions in five dialysis patients, urine volume measurement was available. The mean difference in ultrasound-urine volume mean difference was 0.5 ± 37.8 (range: -68 to 38.2) and the bladder scanner-urine volume was 132 ± 167 (-72 to 397). Two patients with suspected catheter obstructions had ultrasound, bladder scanner, urine volume measurements, respectively: (1) 539, 51, >300 (began voiding before catheter replaced); (2) 666, 68, 1000 with catheter replacement. Conditions leading to greatest differences were obesity, indwelling catheter and ascites.

Conclusions

These results demonstrate the inaccuracy of the bladder scanner. Ultrasound measurements appear more accurate. To remove urinary catheters in patients with minimal to low urine output, serial ultrasound measurements can be used to monitor bladder volumes and return of renal function.

Natural history of post-void residual urine volume over 5 years in community-dwelling older men: The Concord Health and Ageing in Men Project

AIMS

To describe the natural history of post-void residual urine volume (PVR) in community-dwelling older men.

METHODS

The Concord Health and Ageing in Men Project involves a representative sample of community-dwelling men aged 70 and older in a defined geographic area of Sydney, Australia. PVR were measured at baseline and 2-year and 5-year follow-up. The measurements were considered valid when the voided volumes were 150 mL and over. Three-hundred twenty-nine men without conditions that are likely to alter PVR (neurological disorders, prostate cancer, and a history of urological treatment) were included in the analyses.

RESULTS

Baseline PVR were 0-49 mL in 183 men, 50-99 mL in 59 men, 100-199 mL in 72 men, 200-399 mL in 11 men, and 400 mL and over in 4 men. Thirteen out of 314 (4%) men with a baseline PVR of 0-199 mL and 2 out of 11 (18%) men with a baseline PVR of 200-399 mL had surgery for benign prostate enlargement (BPE) or indwelling catheterization over 5 years compared to three out of four men (75%) with a PVR of 400 mL and over. In all 101 men with a baseline PVR of less than 400 mL who did not receive urological treatment during follow-up and had valid PVR data for both 2-year and 5-year follow-up, PVR did not exceed 400 mL at either follow-up time point.

CONCLUSION

Conservative management may be appropriate for most older men with incidentally found elevated PVR of up to 400 mL.

Correlation Between Residual Volume of Male Patients After Uroflowmetry and Random Residual Volume

OBJECTIVES

Our aim was to examine correlation between Post-void residual urine (PVR) after uroflowmetry and random PVR.

METHODS

Male patients reporting to the Urology outpatient clinic with LUTS were selected. Patients' age, prostate volume, bladder capacity, voided volume, maximum flow rate, average flow rate, random PVR and PVR after uroflowmetry were recorded. We evaluated the correlations between these parameters. Also we assessed if there was a difference between random PVR and PVR after uroflowmetry. We divided PVR after uroflowmetry and random PVR into three groups: Group 1: 0-50 mL, Group 2: 51-100 mL and Group 3: >100 mL. Also we divided the patients into two groups according to bladder capacity as Group 1: ≤400 mL and Group 2: >400 mL. We compared these groups to determine whether a significant difference.

RESULTS

Seventy-seven patients applying to the urology outpatient clinic were assessed between 2013 and 2014. PVR after uroflowmetry was significantly higher than random PVR (P < 0.001). When we divided PVR after uroflowmetry and random PVR into three groups there was a significant difference between the groups (P = 0.02). When we divided the patients into two groups according to bladder capacity as Group 1: ≤400 mL and Group 2: >400 mL, PVR after uroflowmetry was different, but random PVR was similar (P < 0.001, P = 0.72).

CONCLUSIONS

PVR after uroflowmetry seems to be incorrectly high in patients whose bladder capacity is above 400 mL.

Falsely Elevated Postvoid Residual Urine Volume in Uterine Myoma

Precise measurement of postvoid residual (PVR) urine volume is a key factor in assessing patients with voiding dysfunction, including those with lower urinary tract problems. The safe and noninvasive ultrasound bladder scan is the preferred mode to measure PVR volume. However, this procedure has a false-positive rate up to 9%, in the presence of ovarian cysts, renal cysts, ascites, or uterine myoma with cystic degeneration. Until now, cystic lesions are known to cause false positivity in ultrasound bladder scanner. However, we encountered falsely-elevated PVR in two cases of non-cystic uterine myomas. We present these cases with detailed radiologic images and volume measurement data.

Acupuncture for Chronic Urinary Retention due to Spinal Cord Injury: A Systematic Review

No systematic review has been published on the use of acupuncture for the treatment of chronic urinary retention (CUR) due to spinal cord injury (SCI). The aim of this review was to assess the effectiveness and safety of acupuncture for CUR due to SCI. Three randomized controlled trials (RCTs) including 334 patients with CUR due to SCI were included. Meta-analysis showed that acupuncture plus rehabilitation training was much better than rehabilitation training alone in decreasing postvoid residual (PVR) urine volume (MD -109.44, 95% CI -156.53 to -62.35). Likewise, a combination of acupuncture and aseptic intermittent catheterization was better than aseptic intermittent catheterization alone in improving response rates (RR 1.23, 95% CI 1.10 to 1.38). No severe adverse events were reported. In conclusion, acupuncture as a complementary therapy may have a potential effect in CUR due to SCI in decreasing PVR and improving bladder voiding. Additionally, acupuncture may be safe in treating CUR caused by SCI. However, due to the lack of high quality RCTs, we could not draw any definitive conclusions. More well-designed RCTs are needed to provide strong evidence.

Changes in Prolapse and Urinary Symptoms After Successful Fitting of a Ring Pessary With Support in Women With Advanced Pelvic Organ Prolapse: A Prospective Study

OBJECTIVE

To estimate the percentage of improvement in prolapse and urinary symptoms and adverse effects in women with advanced pelvic organ prolapse (POP) after 3 months of use of a ring pessary with support.

MATERIALS AND METHODS

In this prospective study, 109 consecutive women with advanced POP were fitted with a ring pessary with support; 73 (73/109, 67.0%) of the women had a successful 3-month pessary fitting trial. Prolapse symptoms, urinary symptoms, and urinary flow parameters were assessed at baseline and at 3 months. Adverse effects were assessed within 3 months. McNemar's test and paired-sample t tests were performed.

RESULTS

Prolapse and urinary symptoms improved from baseline to 3 months, including bulging (90.4% to 23.3%; P <.001) and pressure (64.4% to 13.7%; P <.001). Voiding difficulty improved in 97.8% of the women (45/46; P <.001), splinting improved in 100% (19/19; P <.001), urge urinary incontinence improved in 76.9% (30/39; P <.001), and stress urinary incontinence improved in 58.1% (18/31; P = .025) after 3 months. After pessary treatment, the differences in maximum flow rate, mean flow rate, void volume, and postvoid residual at baseline and 3 months were statistically significant (P <.05). Vaginal discharge (32/73, 43.8%) was the most common adverse event. Vaginal ulcers developed in 7 (7/73, 9.6%) of the women.

CONCLUSION

The ring pessary with support was successfully fitted in patients with advanced POP with a high success rate and few complications. The pessary could resolve more than half of the prolapse and urinary symptoms. Therefore, initial conservative treatment with a ring pessary with support in advanced POP is worthwhile.

The accuracy of three-dimensional bladder ultrasonography in determining the residual urinary volume compared with conventional catheterisation

Objective

To determine the accuracy of three-dimensional bladder ultrasonography (US, using the BVI 3000, Verathon, WA, USA) for determining the residual urinary volume, compared with the conventional catheterisation method.

Patients and methods

We conducted a cross-sectional study at day-care unit of a University hospital after obtaining approval from the Ethics Review Committee of the hospital. Thirty-four patients with lower urinary tract symptoms requiring cystometrography were included. The postvoid volume was measured by bladder US, with three readings taken, and then patient was catheterised using a 12-F Nelaton catheter to measure the urinary volume. The mean of the three readings was compared with the catheterisation volume.

Results

The mean (SD) urinary volumes by US and catheterisation were 261 (186) and 260 (175) mL, respectively, and the correlation (r²) was 0.97. There was no effect of age, gender or body mass index on the accuracy of bladder US, which was accurate even when the urinary volume was ⩽100 mL.

Conclusion

The bladder US estimate is as accurate as catheterisation for determining the postvoid residual urinary volume. Its accuracy was also comparable when the urinary volume is <100 mL, and there was no significant effect of age, gender and body mass index. This system could replace the more invasive catheterisation, and with excellent accuracy.

The usefulness of bladder reconditioning before indwelling urethral catheter removal from stroke patients

OBJECTIVE

The aim of this study was to determine the effects of bladder reconditioning by indwelling urethral catheter (IUC) clamping before IUC removal in stroke patients.

DESIGN

Sixty patients with stroke were randomized to 0-, 1-, and 3-day IUC clamping groups. IUCs were removed without clamping in the 0-day group. In the other two groups, IUCs were clamped for 4 hrs followed by 5 mins of urinary drainage, a cycle repeated over 24 hrs in the 1-day and over 72 hrs in the 3-day clamping groups. Time to first voiding (FV), first voided volume (FV-vol), residual urine volume after FV, mean void volume, and residual urine volume on the third day after IUC removal were measured. We also recorded the voiding method such as self-voiding or intermittent catheterization, incidence of urinary tract infection, subjective complaints, and other complications.

RESULTS

Time to FV, FV-vol, residual urine volume after FV, voiding method, mean voided volume, and residual urine volume on the third day after IUC removal had no significant difference among three groups, nor between the 0-day and the other two clamping groups. We observed a strong negative correlation between age and FV-vol. Of the patients in the 1- and 3-day clamping groups, 3 (7.5%) had symptomatic urinary tract infection and 9 (22.5%) complained of urinary leakage during IUC clamping program.

CONCLUSIONS

Bladder reconditioning through IUC clamping has no noticeable benefits in stroke patients and may induce additional problems. These findings suggest that IUC removal without clamping is superior to IUC clamping for bladder reconditioning in stroke patients.

Early removal of urinary catheter leads to greater post-void residuals in patients with thoracic epidural

BACKGROUND

A recent study showed that the removal of a bladder catheter is safe in presence of thoracic epidural analgesia (TEA). However, the ability to void satisfactorily can be affected. The aim of this investigation is to determine whether patients with TEA are able to recover the micturition process.

METHODS

On the morning after the surgery patients were randomised into two groups: the early removal group (ERG) (n = 101), with the bladder catheter removed at the same time, and the standard group (SG) (n = 104), where the bladder catheter was kept as long as TEA was functioning (on average 3-5 days after surgery). Following the first micturition, patients underwent regular ultrasound scanning of the bladder until a post-void residual (PVR) less than 200 ml was reached.

RESULTS

All of the patients in the ERG and in the SG started to void and recovered satisfactorily their ability to void, reaching a PVR < 200 ml without requiring a transurethral catheterisation. However, the length of time to reach a PVR < 200 ml in the ERG was significantly longer compared with the SG (345 min ± 169 vs. 207 min ± 122, P < 0.0001).

CONCLUSION

In the presence of TEA, the removal of the bladder catheter on the morning after surgery leads to a transient impairment of the lower urinary tract function with no need for re-catheterisation.