Materials and Methods

This cross-sectional study included all UroCuff Tests performed at 103 urology practices in the US. Tests were de-identified prior to collection and analysis. Inclusion criteria required: initial PFS with subsequent tests excluded, voided volume (VV) ≥ 50 ml, at least one cuff inflation, and patient age > 20 years. Pressure (Pcuff), maximum flow rate (Qmax), flow rate efficiency (FRE; Qmax/Pcuff), VV and post void residual (PVR) were plotted by age and stratified by Newcastle Noninvasive Nomogram (NNN) category.

Results

50,680 patients, 20 – 100 years of age (median 66.0) met inclusion criteria. Median Pcuff was 144.3 cmH2O, 60.8% of patients were categorized in the Obstructed or High Pressure/High Flow NNN quadrants. Median Qmax was 10.9 ml/s, 55.8% had Qmax > 10 ml/s. Median VV and post void residual (PVR) were 219.0 ml and 75.0 ml respectively. All measures deteriorated with age (p<0.0001). Pcuff reflects the compensated/decompensated bladder function lifecycle; values initially increased and reached peak pressure at age 62, then decreased by approximately 0.96 cmH2O/year until age 90.

Materials and Methods

Fifty-nine patients with voiding lower urinary tract symptoms (LUTS) underwent a simultaneous PCT and conventional UDS before PVP. The modified International Continence Society (ICS) nomogram was used to confirm bladder outlet obstruction after measuring maximum urinary flow rate and highest pressure at flow interruption. The PCT and UDS results, in terms of modified ICS nomogram predictions, were compared. Their sensitivities, specificities, and positive and negative predictive values were calculated.

Results

Thirty-six patients were diagnosed as obstructed and 23 as non-obstructed/equivocal using the modified ICS nomogram during the PCT. All 36 of the first group were confirmed as obstructed by UDS. Of the 23 diagnosed as non-obstructed/equivocal by the PCT, 14 were confirmed to be non-obstructed by UDS, with nine diagnosed as obstructed. The PCT showed a sensitivity of 80% and a specificity of 100%. The positive and negative predictive values were 100% and 60.9%, respectively.

Materials and Methods

Men scheduled to undergo Holmium laser enucleation of the prostate were enrolled in this study, and all patients underwent the penile cuff test prior to and 3 months after surgery. Patients were categorized as obstructed, nonobstructed, or uncertain by nomogram. Surgical outcomes were assessed by evaluating changes in their international prostate symptom score, quality of life index, and maximum flow rate preoperatively and 3 months postoperatively. The proportion of patients with good outcomes was compared among nomogram-classified groups, and postoperative changes in position on the nomogram were assessed.

Results

A total of 125 patients were analyzed. After surgery, the overall treatment efficacy and symptomatic treatment efficacy were not different between obstructed and nonobstructed patients. However, the maximum flow rate and quality of life score were significantly higher after surgery in obstructed patients compared to nonobstructed patients. After surgery, 75.7% of patients with obstruction and 63.6% of patients categorized as uncertain for obstruction transitioned to the nonobstructed group, while 77.3% of nonobstructed patients remained in the nonobstructed group.

Materials and Methods

A total of 146 consecutive men with an International Prostate Symptom Score (IPSS) >12 and lower urinary tract symptoms (LUTS) for >6 months were included in this single-institution, prospective, diagnostic study. The primary outcome was to evaluate the diagnostic accuracy of PCT. Secondary outcomes included pain severity measured on a visual analog scale (VAS), procedure time, and adverse events. In addition, the sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) were estimated.

Results

Based on the PFS results, the sensitivity of PCT was 89.7%, the PPV 54.2%, the specificity 71.8%, and the NPV 94.9%. The mean pain VAS for the PFS and PCT were 5.04 ± 2.17 and 1.83 ± 1.98, respectively (P < 0.0001). The mean procedure time for PCT (6.3 ± 0.6 min) was shorter than that of PFS (23.3 ± 2.2 min) (P < 0.0001). There were no adverse events reported during PCT.

Materials and Methods

The UroCuff test was compared to invasive urodynamic studies in adult males with lower urinary tract symptoms. Patients undergoing PFS for LUTS presumed to be due to BOO were recruited from a single site to perform a penile cuff test (UroCuff) at the same time as PFS. Standard PFS were performed followed immediately by a penile cuff test in the same test setting. The results were compared using basic statistical analysis.

Results

A total of 19 men were evaluated by both PFS and UroCuff evaluation. Using PFS as the gold standard, the positive predictive value of the UroCuff penile cuff test to diagnose BOO was found to be 92%. The sensitivity of the UroCuff test for detecting BOO was 75%. When compared to PFS, patients preferred the UroCuff 100% of the time.

Patients and Methods

Patients undergoing surgery for prostatic obstruction at Palmerston North Hospital had pre-operative non-invasive urodynamics and completed an International Prostate Symptom Score (IPSS). Catheterised patients were excluded. Two months post-operatively they completed a further IPSS score. An improvement of seven or greater was defined as a clinically successful outcome. Results were compared with the outcome predicted by the nomogram supplied with the urodynamic device.

Results

Data was obtained for 62 patients with mean age 70 years (range 49 to 86 years; SD 9 years). Follow-up was complete for all patients. Thirty-eight patients underwent transurethral resection and 24 holmium laser enucleation of the prostate. Mean IPSS score was 21 (range 5 to 35; SD 6) pre-operatively and 11 (range 1 to 31; SD 9) post-operatively. Thirty-five patients were predicted obstructed and 27 not obstructed. 94% of those predicted obstructed had a successful outcome (p < 0.01). 70% predicted as not obstructed did not have a successful outcome after surgery (p < 0.01).

Methods

We enrolled male patients with lower urinary tract symptoms candidates for TURP. Each of them underwent a PCT and a subsequent PFS. A statistical analysis was performed: sensitivity (SE), specificity (SP), positive predictive value (PPV), negative predictive value (NPV), likelihood ratio and ratio of corrected classified were calculated. Fisher exact test was used to evaluate relationships between PCT and maximal urine flow (Qmax): a p-value < 0.05 was considered statistically significant.

Results

We enrolled 48 consecutive patients. Overall, at PCT 31 patients were diagnosed as obstructed and 17 patients as unobstructed. At the subsequent PFS, 21 out of 31 patients diagnosed as obstructed at PCT were confirmed to be obstructed; one was diagnosed as unobstructed; the remaining 9 patients appeared as equivocal. Concerning the 17 patients unobstructed at PCT, all of them were confirmed not to be obstructed at PFS, with 10 equivocal and 7 unobstructed. The rate of correctly classified patients at PCT was 79% (95%-CI 65%-90%). About detecting obstructed patients, PCT showed a SE of 100% and a SP of 63%. The PPV was 68%, while the NPV was 100%.

NHS Centre for Evidence-based Purchasing Verdict – Significant Potential:
The Mediplus CT3000 system offers greater accuracy in diagnosis of BOO than diagnosis based on flow rate measurement alone. Recent results (3) suggest its prediction of outcome from surgery rivals that offered by invasive urodynamic studies, though this has not been conclusively proven by this limited evidence. The invasive approach also provides additional information, and therefore remains the gold standard for the diagnosis of BOO in men. The existing evidence supports the manufacturer’s claim that the CT3000 system has a useful role as an adjunct to current methods. Diagnoses based on CT3000 and urine flow measurement can be compared. Where there is agreement, surgery is indicated, and where there is disagreement or uncertainty, follow up invasive urodynamics are indicated. This approach may well reduce the number of ineffective surgical prostatectomies while also reducing the number of invasive studies, both of which carry associated costs and risks. Independent validating studies on the Mediplus CT3000 cuff system are recommended, and a multi-centre trial is reported to be underway (3). A detailed economic evaluation is also recommended, considering both the costs and consequences of the diagnostic accuracy of the CT3000 system.

Download

Materials and Methods

This is a narrative review derived from the clinical and scientific knowledge of the authors together with consideration of selected literature. The CT3000 UroCuff test was compared to traditional catheter based urodynamic studies in adult males with lower urinary tract symptoms.

Results

Consideration of measured bladder pressure urinary flow rate during voiding in an invasive pressure flow study is considered the gold standard for categorization of bladder outlet obstruction (BOO). The diagnosis is currently made by plotting the detrusor pressure at maximum flow (PdetQmax) and maximum flow rate (Qmax) on the nomogram approved by the International Continence Society. This plot will categorize the void as obstructed, equivocal or unobstructed. The invasive and relatively complex nature of this investigation has led to a number of inventive techniques to categorize BOO either by measuring bladder pressure non-invasively or by providing a proxy measure such as bladder weight.

Methods

The test involves the controlled inflation of a penile cuff during micturition to interrupt voiding and hence estimate isovolumetric bladder pressure (pves.isv). The validity, reliability, and clinical usefulness of the test were determined in a number of studies in men with LUTS.

Results

The penile cuff test can be successfully performed in over 90% of men with LUTS. The reading of cuff pressure at flow interruption (pcuff.int) gives a valid and reliable estimate of invasively-measured pves.isv and when combined with the reading for maximum flow rate obtained during the test (Qmax) produces an accurate categorization of bladder outlet obstruction (BOO). Use of this categorization prior to treatment allows improved prediction of outcome from prostatectomy.

Materials & 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 H₂O, 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.

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 H₂O. Of the men 33% changed diagnostic category on the Newcastle nomogram, while 47% maintained a consistent diagnosis of obstruction or no obstruction.

Materials and Methods

A prospective cohort of men undergoing transurethral prostate resection was recruited, of whom 143 (69%) underwent noninvasive pressure flow study using the penile cuff technique before and 4 months following surgery. Cuff pressure required to interrupt voiding, estimated isovolumetric bladder pressure and maximum flow rate were recorded during a single void. Values were plotted on a nomogram categorizing cases as obstructed (upper left quadrant), not obstructed (lower right quadrant) or diagnosis uncertain (upper right and lower left quadrants). Changes in maximum flow rate, cuff pressure required to interrupt voiding and nomogram position following transurethral prostate resection were then analyzed.

Results

Transurethral prostate resection resulted in an improved flow rate for all diagnostic groups, which was highest for obstructed cases with a mean ± SD increase of 11 ± 6 ml second (p <0.01). Men categorized with obstruction and those placed in the upper right quadrant showed significant decreases in cuff pressure required to interrupt voiding following transurethral prostate resection with a mean decrease of – 45 ± 35 and – 48 ± 32 cm H₂O, respectively (p <0.01). The number of cases classified as not obstructed increased from 28 (19%) preoperatively to 114 (80%) after transurethral prostate resection.

Methods

A consecutive cohort of 208 men undergoing TURP following standard assessment in our institution was recruited, and 179 (86%) completed the protocol. Each subject underwent a penile cuff test prior to surgery; outcome was assessed by change in IPSS at 4 mo. The proportion of men with good outcome (>50% reduction in IPSS) was compared according to categorisation by noninvasive bladder pressure and urine flow measurements.

Results

The cuff test was completed by 93% of men with 2% experiencing an adverse event. Men categorised as having BOO by the test (37% of total) had an 87% chance of a good outcome from TURP (p < 0.01), whilst of those deemed not obstructed (19% of total) 56% experienced good outcome (p < 0.01). For the remaining men not categorised in these two groups, 77% had good outcome, which was identical to the result of the cohort as a whole (77%, p = NS).