Determination Of Bladder Volume Research Articles

The Reliability of Bladder Volume Determination in Children Using Portable Ultrasonographic Scanner in Standing Position

The Reliability of Bladder Volume Determination in Children Using Portable Ultrasonographic Scanner in Standing Position

Usefulness of fetal urine production measurement for prediction of perinatal outcomes in uteroplacental insufficiency.

To evaluate whether fetal urine production measurement is useful for predicting adverse outcomes in patients with uteroplacental insufficiency. We enrolled patients with uteroplacental insufficiency at 24 to 40 weeks' gestation and normal pregnancies matched for gestational age and divided them into 3 groups according to perinatal outcomes: group 1 (n = 141), a control group of normal pregnancies; group 2 (n = 29), uteroplacental insufficiency without adverse outcomes; and group 3 (n = 18), uteroplacental insufficiency with adverse outcomes. An adverse outcome was defined as 1 or more of the following: (1) cesarean delivery because of fetal distress; (2) admission to the neonatal intensive care unit; (3) cord arterial pH less than 7.15 at birth; and (4) low 5-minute Apgar score (<7). The fetal urine production rate was obtained by serial bladder volume measurement using virtual organ computer-aided analysis. For bladder volume determination, we scanned the bladder in the 3-dimensional mode and defined the bladder surface contour in the reference plane, repeating the rotation of the reference plane with an angle of 30° and determining the surface contour on each plane. Statistical methods, including the Mann-Whitney U test, Fisher exact test, χ(2) test, and Kruskal-Wallis analysis of variance, were used. Group 3 had a lower mean fetal urine production rate than groups 1 and 2, whereas the urine production rate was not different between groups 1 and 2 (group 1, 49.0 mL/h; group 2, 59.4 mL/h; group 3, 20.7 mL/h; P < .001 between groups 1 and 3 and between groups 2 and 3). This difference between groups 2 and 3 remained significant after adjusting for the amniotic fluid index, umbilical artery Doppler pulsatility index, and presence of fetal growth restriction. Uteroplacental insufficiency cases with adverse perinatal outcomes had a lower fetal urine production rate than those without adverse outcomes. This difference might be used to predict adverse perinatal outcomes in uteroplacental insufficiency.

Bladder Volume Determination: Two-dimensional Versus Three-dimensional Transvaginal Ultrasound

To compare the results of in vivo measurement of bladder volume using three-dimensional (3D) ultrasound with that obtained from 2D ultrasound. Forty female inpatients with benign gynecologic diseases had urinary bladder volume determined by ultrasound before surgery. Each patient was initially scanned using the conventional transvaginal 2D ultrasound method, followed by transvaginal 3D ultrasound, and finally underwent sterilized catheterization to obtain the actual bladder volume. The relationships between actual bladder volume and each of the 2D and 3D scan volumes were determined. The patients' bladder volumes varied from 30 mL to 590 mL. The mean value of the error measurement using transvaginal 2D ultrasound estimation was 15.7%, and the correlation coefficient was 0.90. The mean value of the error measurement using transvaginal 3D ultrasound estimation was -8.48%, with a correlation coefficient of 0.97. Our data showed that the 3D scan tended to underestimate the actual bladder volume, while the 2D scan tended to overestimate it. Nevertheless, each method would suffice as a reliable noninvasive means of predicting actual bladder volume.

Noninvasive bladder volume measurements based on nonlinear wave distortion

The purpose of this study is to suggest a new approach to measure noninvasively the fluid content of a human cavity; in particular, the bladder volume. Determination of bladder volume is important clinically for patients suffering from bladder dysfunction. Several ultrasonic methods were proposed in the past for such a purpose. Most of these methods are based on multiple cross-sectional images and detection of echoes from the bladder wall. We propose here, in a first step, a simple approach that is able to provide an indication of whether or not the bladder volume has exceeded a certain threshold volume. Second, the possibility of accurate volume assessment will be discussed. The approach takes advantage of the difference in harmonic generation of liquids (urine) and tissues. We know that nonlinear effects occur most strongly when ultrasound (US) propagates through liquids with relatively low acoustic attenuation, such as water or urine. However, within soft tissues, the tendency for wave distortion to occur is limited as a result of different acoustic characteristics, most notably the attenuation. Our method is based on measuring the presence of harmonics in an echo from a region-of-interest (ROI) at fixed depth beyond the bladder. The harmonic content in the echo will increase with increase of fluid in the echo path. Phantom measurements were carried out with a single-element transducer and a phased-array transducer. Phantoms containing different volumes were used. Furthermore, measurements on volunteers were performed. The results confirmed that the harmonic content of an echo measured at a deep ROI increases for a full bladder and decays strongly after the volunteer has voided. These preliminary results demonstrate the feasibility of the approach. (E-mail: a.bouakaz@erasmusmc.nl)

Place d’un échographe vésical portable dans la prise en charge des troubles de la vidange vésicale après accident vasculaire cérébral

OBJECTIVE: To determine the usefulness of a portable ultrasonographic device in the management and rehabilitation of stroke patients’ bladder voiding impairment in the early stage and to propose a well-fitted screening protocol. MATERIAL AND METHOD: A prospective observational study of 33 inpatients admitted into our stroke rehabilitation program. A urinary elimination assessment protocol defines the criteria of intermittent catheterization. The determination of bladder volume was performed with a Bladderscan BVI 3000 portable ultrasonographic device. RESULTS: Urinary retention was present in ten of the 33 patients at admission, who were started on one or many intermittent catheterizations. Retention was resolved for seven of them at discharge. The portable ultrasonographic device allows a very accurate bladder volume assessment, especially useful in at-risk patients: those with cognitive impairments, diabetes mellitus, and prestroke urinary pathology. A new version of our first screening protocol increases the ability to detect patients with true urinary retention. Results are discussed according to the literature data. CONCLUSION: The portable ultrasonographic device is a simple and noninvasive tool, useful for diagnosis, follow-up and therapy guidance of urinary retention after stroke. An adapted protocol is proposed in order to assess and rehabilitate this trouble. The goal is to avoid long-term catheterization and its linked infectious risk.

Bladder volume determination: Portable 3-D versus stationary 2-D ultrasound device

Schnider P, Birner P, Gendo A, Ratheiser K, Auff E. Bladder volume determination: portable 3-D versus stationary 2-D ultrasound device. Arch Phys Med Rehabil 2000;81:18-21. Objective: To investigate how accurately a portable three-dimensional (3-D) scanner and a multipurpose two-dimensional (2-D) real-time scanner determined bladder volumes. Study Design: Prospective, controlled clinical trial, single-blind, crossover design. Setting and Participants: Twenty-three inpatients with permanent bladder catheters participated voluntarily in this study. Methods: The bladders of 20 patients were filled through an indwelling catheter with 60, 110, 160, 210, and 260mL sterile normal saline. Volumes were measured twice with each device. Measurements were compared with the actual bladder volumes. Results: The 2-D device showed better reproducibility, particularly at lower bladder volumes. The 3-D scanner showed a significant difference between the two measurements at 160mL (p < .05) and had poor reproducibility at 110, 210, and 260mL. Both devices overestimated actual bladder volume at fillings of <160mL and underestimated it at fillings of ≥160mL. The range between the 25th and 75th percentiles was always larger for the 3-D scanner, except for the 210mL reading. Conclusion: Both devices showed sufficient accuracy for clinical practice. Ultrasound measurements of >110mL should be followed by catheterization to detect potentially harmful bladder volumes. © 2000 by the American Congress of Rehabilitation Medicine and the American Academy of Physical Medicine and Rehabilitation

Bladder volume determination: Portable 3-D versus stationary 2-D ultrasound device

Bladder volume determination: Portable 3-D versus stationary 2-D ultrasound device

151. Bladder Volume Determination: Portable 3-D Versus Stationary 2-D Ultrasound Device Peter Schnider, Peter Birner, Alexandra Gendo, and Eduard Auff (all from Vienna, Austria

151. Bladder Volume Determination: Portable 3-D Versus Stationary 2-D Ultrasound Device Peter Schnider, Peter Birner, Alexandra Gendo, and Eduard Auff (all from Vienna, Austria

Validation of an ultrasound scanner for determing urinary volumes in surgical patients and volunteers.

As bladder distension related to anaesthesia puts patients at risk for permanent dysfunction, peri-operative determination of bladder volume is of great importance. The aim of this study is to validate an ultrasonic imaging device for determing bladder urine volume. To evaluate a broad volume range, ultrasonically scanned volumes were compared to true urinary volumes both in surgical patients and in volunteers. After institutional approval and informed consent 60 healthy volunteers were asked not to void for as long as possible. After ultrasound measurements (BladderScan BVI 2500, Diagnostic Ultrasound, Redmond WA, U.S.A.) they voided and true urinary volumes were measured. Fifty surgical patients scheduled for procedures requiring urinary catheterisation were studied. Pre- and post-induction of anaesthesia ultrasound measurements were recorded, followed by urinary catheterisation and measurement of true urinary volume. Urine volumes were compared using Student t-tests and Wilcoxon Rank Tests (p < 0.05). For validation linear regression was used together with Bland-Altman analyses. Ultrasonic scanning underestimated the true urine volume by about 7% over the whole volume range (17 ml to 970 ml). Underestimation was larger in females than in males (p < 0.02). R2 values for correlation of measured and scanned urinary volumes ranged between 0.92 and 0.95. Bland and Altman analyses showed a bias of 31 ml in volunteers and of 19 ml in patients and a precision of 110 ml and 80 ml, respectively. The ultrasonic imaging device can be used peri-operatively to establish bladder volume, taking into account the 7% underestimation of the bladder volume.

Assessment of urinary bladder volume in dogs by use of linear ultrasonographic measurements

SUMMARY Objective To evaluate accuracy of formulas derived from linear ultrasonographic measurements and used in human beings to assess urinary bladder volume as a method of estimating bladder volume in dogs and to test reproducibility of ultrasonographic measurements of linear bladder dimensions. Animals 64 live dogs (for bladder volume determination) and 31 fresh canine cadavers (for ultrasonographic assessment of reproducibility of measurements). Procedure Maximal length, longitudinal and transverse depth (DL and DT), and width were measured from the maximal longitudinal and transverse images. Bladder volume was estimated, using 6 formulas, and calculated volumes were compared statistically with the actual volume obtained by catheterization, using paired nonparametric tests. Reproducibility of bladder dimensions was investigated by measuring length, DL, DT, and width 3 times from each image of section. Measurements of depth (DL and DT) also were compared. Results Calculations of bladder volume from linear dimensions, using a formula described for use in human beings, gave a satisfactory indication of actual bladder volume; the median difference between actual and calculated volumes was only 5 ml. Bladder volume estimations were less accurate when large-volume bladders were measured. Matching between repeated measurements was significant (P &lt; 0.005 for longitudinal bladder length and P &lt; 0.0001 for bladder depth and width). Measurements of DL and DT were significantly (P &lt; 0.01) different, with DL greater than DT. Conclusions Ultrasonographic assessment of bladder volume in dogs by application of the formula is sufficiently accurate for most clinical purposes. Clinical Relevance Ultrasonography would be a useful method of estimating bladder volume in dogs with severe obstruction or dysfunctional voiding of urine. (Am J Vet Res 1998;59:10–15)

Three-dimensional ultrasound device for rapid determination of bladder volume

We sought to assess the accuracy, reliability, and clinical utility of the noninvasive determination of bladder volume using an automated, compact three-dimensional (3-D) ultrasound device. We prospectively tested 249 adult outpatients for accuracy (n = 182), by comparing scan versus catheter volumes, or reliability (n = 67), by comparing the scan readings of two independent observers. Two models of the bladder scan device were tested (BVI-2500, 1994 and 1995 models). Scan and catheter volumes were correlated (y = 1.02x + 12.6, R2 = 0.90, P < 0.001) across a range of zero to 1015 cc, regardless of which machine model was used. Scan volume underestimated catheter volume by an average of 10 cc in men and 20 cc in women. If a scan-predicted volume of 100 cc or greater were used as a cutpoint for clinical importance, the device exhibited a sensitivity of 97%, a specificity of 91%, and an overall accuracy of 94%. These results were not affected by age, gender, height, weight, diagnosis, uterine presence/prostate size, or user experience. The two observers, one a graduate physician and the other a college student, achieved essentially the same volume determinations (y = 0.96x + 0.13, R2 = 0.90, P < 0.001). Volume determinations obtained with the bladder scan device are accurate and reliable in adult outpatients. A special technician is not required. These results may be attributable to use of automated planimetry and 3-D volumetry, rather than a fixed geometric formula, to custom measure each bladder shape.

Ultrasonic determination of bladder volume in patients with spinal cord injury

Ultrasonic determination of bladder volume in patients with spinal cord injury

Bladder Volume Determination Using a Dedicated, Portable Ultrasound Scanner

Urethral catheterization, the standard method for measurement of bladder volume, is associated with patient discomfort plus the risks of urethral trauma and urinary tract infection. A portable ultrasound instrument that automatically determines bladder volume was used for 164 determinations and the digital readout correlated with the catheterized volume (r2 equals 0.79). This instrument is a noninvasive alternative to urethral catheterization for the determination of bladder volume in most patients. (J. Urol, 143: 909–911, 1990)