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Purpose: We developed a prototype device using an automatically controlled inflatable penile cuff to measure bladder voiding pressure continuously and non-invasively in men. The purpose of this study was to validate the pressure measurements made by this device by comparison to those during simultaneous invasive PFS., Methods: A device was developed to automatically modulate flow rate by controlling pressure in a penile cuff. Men undergoing conventional urodynamics studies were recruited to have an additional fill-void cycle whilst using the new device. We report on 40 men using a standardized protocol. Pressure measured by this device was compared with simultaneous vesical pressure by evaluating maximum pressure during voiding, and calculating the root mean square (RMS) difference between p(cuff) and p(ves) ., Results: We recruited 80 men of whom 18 were excluded, 22 were involved in initial development phase and 40 in the standard protocol. Mean (SD) difference between maxima of p(cuff) and p(ves) (1.3 (15.6) cmH(2) O) was not significant. In 20 (50%) men, agreement between p(cuff) and p(ves) throughout the void was moderate or good (RMS difference <20 cmH(2) O). Causes of unsuccessful measurements were identified., Conclusions: Although a prototype device, this technique appears to be promising for continuous non-invasive bladder pressure measurement. From the results of this study a number of improvements have been recommended and implemented. The next generation of this technique will allow assessment of clinical application., (Copyright © 2011 Wiley Periodicals, Inc.)

Purpose: We assessed variability in interpreting noninvasive measurements of bladder pressure and urine flow between experienced and novice users of the penile cuff., Materials and Methods: Urodynamicists at 6 sites were asked to use the penile cuff test as part of clinical assessment in 30 men presenting with lower urinary tract symptoms. After a short training period they measured maximum flow rate and cuff interruption pressure from penile cuff test recordings to enable categorization of bladder outlet obstruction using a nomogram. Similar measurements were then made on the same traces by 2 expert observers from the originating center. Interobserver differences were assessed., Results: Complete agreement on obstruction categorization was seen in 77% of subjects, which increased to 86% when plots positioned on category boundary lines were allocated to the favored category. The 95% confidence limits of interobserver variability in maximum flow rate and cuff interruption pressure measurements were +/- 1.7 ml per second and +/- 13 cm H(2)O, respectively, although a small number of studies yielded discrepancies between observers that were larger than expected. They arose from complex recordings but were equally likely between experts as between expert and novice. Investigation of the causes suggested in some cases how such discrepancies may be avoided in the future., Conclusions: The excellent level of agreement in measurement and categorization after a short training period suggests that introducing the penile cuff test as part of assessment in men with lower urinary tract symptoms would be straightforward.

Purpose: We performed a pragmatic study of the penile cuff test, a noninvasive method of categorizing bladder outlet obstruction, at a number of United Kingdom urology centers remote from the originating site. We report the agreement of the test and the subsequent retest using the cuff test in the short term., Materials and Methods: Men requiring urodynamic investigation for lower urinary tract symptoms were recruited from 6 sites to perform a penile cuff test twice at an interval of approximately 4 weeks. Tests were analyzed by a single interpreter to assess differences in the flow rate, cuff interruption pressure and diagnostic categorization in an individual between the 2 tests due to measurement and physiological error., Results: A total of 136 men (69%) performed 2 suitable cuff tests at a median of 20 days (IQR 8-31). The mean +/- SD difference between the 2 tests in the maximum flow rate was 0.2 +/- 3.7 ml per second and in cuff interruption pressure was 4.0 +/- 26 cm H(2)O. Of the men 33% changed diagnostic category on the Newcastle nomogram, while 47% maintained a consistent diagnosis of obstruction or no obstruction., Conclusions: Diagnostic category repeatability was similar to that of conventional urodynamics, although there was greater variability in pressure measurements. This supports widespread routine use of the penile cuff test.