Simon St. C. Carter

THE DIAGNOSIS OF BLADDER OUTLET OBSTRUCTION IN MEN BY ULTRASOUND MEASUREMENT OF BLADDER WALL THICKNESS

PURPOSE The objective of the study was to investigate specificity and sensitivity of bladder wall thickness in the diagnosis of bladder outlet obstruction. MATERIALS AND METHODS The study included 174 patients referred to our prostate centers for lower urinary tract symptoms. Free uroflowmetry and pressure-flow studies were performed in duplicate as part of the diagnostic evaluation. After the 2 voiding studies were done the bladder was filled to 150 ml. and wall thickness was measured via suprapubic ultrasound. Bladder outlet obstruction was diagnosed and graded according to the Abrams-Griffiths and Schäfer nomogram as well as to the group specific urethral resistance algorithm. RESULTS A significant correlation (r > 0.6, p < or = 0.007) was found between bladder wall thickness and all parameters of the pressure-flow study. A bladder wall thickness of 5 mm. appeared to be the best cutoff point to diagnose bladder outlet obstruction, since 63.3% of patients with bladder wall thickness less than 5 mm. were unobstructed while 87.5% of those with a bladder wall thickness 5 mm. or greater were obstructed. Bladder wall thickness out performed uroflowmetry in terms of specificity and sensitivity in the diagnosis of outlet obstruction as demonstrated by an area under curve value of 0.860 versus 0.688 in the receiver operator characteristics analysis. CONCLUSIONS Measurement of bladder wall thickness appears to be a useful predictor of outlet obstruction with a diagnostic value exceeding free uroflowmetry although it does not represent a substitution to invasive urodynamics. These data support the hypothesis that the relationships between morphology and function are of clinical importance.

A PROSPECTIVE STUDY OF THE SAFETY AND EFFICACY OF SUPRAPUBIC TRANSVESICAL PROSTATECTOMY IN PATIENTS WITH BENIGN PROSTATIC HYPERPLASIA

PURPOSE We investigate the safety and efficacy of suprapubic transvesical prostatectomy, and the change in bladder wall thickness after surgery. MATERIALS AND METHODS We conducted a prospective 1 center study of 32 consecutive patients who underwent transvesical prostatectomy from December 1996 to March 1997 for benign prostatic hyperplasia with large prostate volume, who were followed for 1 year. Pressure flow study and transrectal sonography were performed at baseline and repeated at 6 months. Bladder wall thickness was measured at baseline and regular intervals postoperatively. A morbidity questionnaire was completed during the first 6 weeks after surgery. RESULTS An average of 63 gm. prostate adenoma were enucleated at surgery. An indwelling catheter was required for an average plus or minus standard deviation of 5.4 +/- 2.6 days after treatment. The International Prostate Symptom Score decreased from 19.9 +/- 4.4 to 1.5 +/- 2.7 and the quality of life score decreased from 4.9 +/- 1.0 to 0.2 +/- 0.4 at year 1, respectively. Maximum flow rate improved from 9.1 +/- 5.3 to 29.0 +/- 8.9 ml. per second. Residual urine decreased from 128 +/- 113 to 8 +/- 18 ml. Before surgery 30 patients had obstruction and 2 were in the equivocal zone of the International Continence Society nomogram. At 6 months after prostatectomy 30 patients did not have obstruction, and 2 who were subsequently operated on for bladder neck sclerosis were equivocal and had obstruction, respectively. No patient had significant postoperative bleeding and no heterologous blood transfusions were required. There were 4 men who had urinary tract infection and 1 who had wound infection. A slight decrease in erectile function was observed 6 weeks postoperatively, and no change in patient libido and quality of sex life was reported. The total complication rate was 31.3%. The bladder was unstable in 7 men before and 3 after surgery. A significant decrease in bladder wall thickness was observed from 5.2 +/- 0.7 at baseline to 2.9 +/- 0.9 mm. at year 1 postoperatively. CONCLUSIONS Our study confirms the excellent clinical outcome of transvesical prostatectomy, and rapid improvement of most subjective and objective parameters during the 4 weeks after surgery. Bladder hypertrophy appears to be significantly reduced after prostate surgery. The urodynamic results in patients who underwent open surgery probably represent the maximum obtainable relief of obstruction and should be considered the reference standard to which all other treatments, including transurethral resection, should aspire.

Serum prostate-specific antigen to predict the presence of bladder outlet obstruction in men with urinary symptoms

To determine whether prostate specific antigen (PSA) level can usefully predict or exclude bladder outlet obstruction (BOO), in men with lower urinary tract symptoms (LUTS).

The Prediction of Clinical Outcome from Transurethral Microwave Thermotherapy by Pressure-Flow Analysis: A European Multicenter Study

A total of 100 patients treated with a single session of microwave thermotherapy at 4 European centers was stratified according to 2 different types of obstruction (constrictive and compressive) and compared to clinical outcome at 6 months. Patients had a Madsen-Iversen score of 8 or more, maximum flow rate of 15 ml. per second or less and residual urine volume of 300 ml. or less at entry. The change in Madsen-Iversen score was the same in the 2 groups. Maximum flow rate increased from 8.71 +/- 2.62 to 14.73 +/- 4.04 ml. per second in the constrictive group, and from 8.54 +/- 2.26 to 10.41 +/- 4.52 in the compressive group (p < or = 0.0001). Residual urine decreased from 96.00 +/- 72.85 to 40.34 +/- 56.33 ml. in the constrictive group and from 109.86 +/- 67.09 to 84.65 +/- 81.45 ml. in the compressive group (p < or = 0.0001). Success, as defined by an increase of 50% or more in maximum flow rate and Madsen-Iversen score, was noted in 68% of the constrictive but only 15% of the compressive groups (p < or = 0.0001 chi-square test for trend). Selection by pressure-flow criteria for patients being considered for thermotherapy should improve the overall clinical results.

Variability of detrusor overactivity on repeated filling cystometry in men with urge symptoms: comparison with spinal cord injury patients

To investigate the variation in urodynamic variables during repeated filling cystometry and the impact that the variability had on the observed incidence of detrusor overactivity, to evaluate the correlation of detrusor overactivity with the symptoms of urge in men with lower urinary tract symptoms (LUTS), and to compare the variability of detrusor overactivity in men with LUTS to that in men with spinal cord injury (SCI).

A PROBABILITY BASED SYSTEM FOR COMBINING SIMPLE OFFICE PARAMETERS AS A PREDICTOR OF BLADDER OUTFLOW OBSTRUCTION

PURPOSE We explored the relationships of office assessment of lower urinary tract symptoms, transrectal ultrasound measurement and the bladder outlet obstruction index, as derived from pressure flow studies. We also developed and validated a multivariate analysis for predicting the bladder outlet obstruction index. MATERIALS AND METHODS We evaluated 384 men with lower urinary tract symptoms using the International Prostate Symptom Score, maximum urine flow, post-void residual urine, transrectal ultrasound and urodynamic studies. Data were analyzed by multiple linear regression with continuous variables. A simple algorithm, that is the predicted bladder outlet obstruction index, was created using the best fit variables identified from a derivation set and assessed in a separate validation set. The predicted index was applied to predict the probability of actual obstruction according to office parameters. RESULTS Maximum urine flow and total prostate volume predicted the bladder outlet obstruction index most completely (adjusted R2 = 0.50, F 75.9, p <0.0001), while other variables were not helpful. These variables were used to create the predicted bladder outlet obstruction index algorithm, antilog10 (2.21 - 0.50 log maximum urine flow + 0.18 log total prostate volume) - 50. In the 42% of patients with a predicted index of greater than 40 there was a 92% risk or positive predictive value of equivocal or worse obstruction, whereas a predicted index of less than 20 in 23% indicated a 4% risk of significant obstruction. CONCLUSIONS The bladder outlet obstruction index can be predicted from maximum urine flow and prostate volume. Development of the predicted bladder outlet obstruction index algorithm enables the mathematical prediction of obstruction from these simple measures. Using the predicted bladder outlet obstruction index clinicians can determine the risk of obstruction in individuals. In 65% of patients we predicted equivocal or worse obstruction with greater than 90% confidence.

Payment by results: financial implications of clinical coding errors in urology.

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Early Treatment of Benign Prostatic Hyperplasia Implications for Reducing the Risk of Permanent Bladder Damage

A significant change has occurred in the management of symptomatic benign prostatic hyperplasia (BPH) since effective pharmacological treatment became available and led to a significant decrease in the number of surgical procedures in many Western countries. The hypothesis of a causative role of benign prostatic enlargement and bladder outflow obstruction (BOO) in lower urinary tract symptoms (LUTS) was based on the association between prostate growth and symptoms of prostatism in elderly men and on the dramatic reduction of LUTS upon relief of obstruction. Careful investigation into the epidemiology of LUTS and BPH failed to confirm such an association and opened new perspectives in the pathophysiology of lower urinary tract dysfunction and symptoms.The observation that LUTS were equally distributed in male and female cohorts, when matched for age, moved attention away from the prostate and towards the urinary bladder and its aging-related disorders. When BPH surgery was developed, the management of the disease was aimed at preventing death from chronic renal failure, but the picture has changed and modern medical treatment is now aimed at improving the patient’s quality of life.The increasing size of elderly populations in the Western world and the consequent financial constraints of national healthcare systems have raised the question of when pharmacological treatment of symptomatic BPH should be initiated. Retrospective and prospective analysis of various BPH populations and clinical studies has clearly defined the capacity of pharmacological treatment to reduce the incidence of complications of BPH, such as acute urinary retention and the need for surgery, but the cost/benefit ratio is unclear. Notwithstanding the limitations inherent in the experimental models, there is evidence from various animal models, investigating the pathophysiology of the urinary bladder in the presence of outflow obstruction, to indicate that a cause and effect relationship between BOO and bladder decompensation has been established and to support the hypothesis that permanent bladder damage may occur when the obstruction is not relieved early enough. Preliminary experimental evidence also suggests that α1-adrenoceptor antagonists may have a role in reducing the damaging effects of BOO on the urinary bladder.At present, there is no evidence to support the need for early pharmacological treatment of symptomatic BPH with no BOO beyond the obvious target of improving the patient’s quality of life. The evidence for early treatment of BOO and the need to preserve bladder function is clear. Further experimental and clinical research is required to identify markers of early bladder damage and decompensation which can be used to select patients for early pharmacological treatment of BPH.

Analysis of outcome after thermotherapy using different classifications of bladder outlet obstruction

The urodynamic profiles of 97 patients with benign prostatic hyperplasia undergoing low‐energy transurethral microwave thermotherapy (TUMT) for lower urinary tract symptoms were analysed using the Abrams/Griffiths nomogram, the urethral resistance algorithm, the linPURR, Schäfer nomogram, and the CHESS classification.