Urodynamics in the management of benign prostatic hypertrophy

When should we use urodynamic testing? Recommendations of the Italian Society of Urodynamics (SIUD). Part 2 - Male and neurogical population

Recent studies in literature, have raised some doubts on the routine use of urodynamic testing. Many physicians and articles recommend a selective use of this tool, considering carefully risks and benefits. These recommendations are intended to guide clinicians in the right selection of the male and neurological patients to submit to a urodynamic evaluation. This is the second part of a previous article regarding the urodynamic recommendations in the female population. We reviewed the literature, regarding the use of UDS in male and neurological population with lower urinary tract symptoms (LUTS). Specifically, we analyzed and compared the guidelines and recommendations of the most important urology and urogynecology international scientific societies. These publications were used to create the evidence basis for characterizing the recommendations to perform urodynamic testing. A panel of 10 experts was composed and Delphi process was followed to obtain the panelist consensus. The final recommendations were approved by the unanimous consensus of the panel and compared with the best practice recommendations available in the literature. The recommendations are provided for diagnosis and management of common LUTS in male and neurological population. This review provides a summary of the most effective utilization of urodynamic studies for the global evaluation of patients with LUTS, and how to use them when really needed, avoiding unnecessary costs and patient inconveniences.

Urinary bladder bilharziasis as a cause of impaired bladder muscle contractility

In an attempt to evaluate the effect of bilharziasis on bladder contractility as a factor in the genesis of voiding disorders, 44 cases of bilharzial bladder neck obstruction diagnosed using traditional methods (symptomatological, radiographic, and endoscopic) were subjected to complete urodynamic evaluation (flowmetry, cystometry, pressure/flow study, and stop-flow test). Their parameters were compared with those of 28 patients with urodynamically obstructed benign prostatic hyperplasia and 8 nonsymptomatic controls. Contractility parameters (isometric detrusor pressure, maximum estimated flow rate, detrusor power at maximum flow) were calculated for the studied cases and their distribution according to the Schafer pressure/flow diagram was evaluated. Bladder biopsy including the detrusor was evaluated in all 72 patients. Poor bladder contractility associated with an extensive bilharzial effect on the detrusor muscle was found to be the major abnormality in 20 of 44 patients with presumed bilharzial bladder neck obstruction with no evidence of urodynamic outflow obstruction. We believe such a workup is essential in cases of suspected obstruction associated with bilharziasis to throw light on the pathophysiology of the voiding disorders, avoid unnecessary surgery, and provide a better prognosis.

Improving the utility of urine flow rate to exclude outlet obstruction in men with voiding symptoms

OBJECTIVES

Many older men with voiding symptoms do not have bladder outlet obstruction (BOO) but have conditions amenable to medical treatment. If primary care providers could reliably exclude men who have BOO, then they could initiate appropriate evaluation and treatment in a substantial proportion of the remainder. Urine flow rate, although widely used, is insufficiently sensitive to exclude BOO reliably. We investigated whether the decline in flow rate with age could be utilized to improve the utility of flow rate for excluding BOO in symptomatic men, especially when combined with knowledge of the patient's postvoiding residual volume (PVR).

DESIGN

Prospective study using two patient cohorts.

SETTINGS

A Veterans Affairs urology clinic serving community-dwelling and institutionalized healthy older men.

PARTICIPANTS

111 men with voiding symptoms (mean age 72.4 +/- 9.2 years).

MEASUREMENTS

Maximum urine flow rate, measured with standard flowmeter, and PVR, measured by catheterization. BOO was determined by multichannel videourodynamic testing.

RESULTS

The sensitivity of flowrate for BOO increased significantly with age (P = .0001) and did not appear to be confounded by comorbid conditions. An algorithm incorporating age, flow rate, and PVR had a sensitivity of 90%, specificity of 43%, and accuracy of 74% in screening for BOO. The algorithm's sensitivity was better than that of flow rate alone (55%); its sensitivity was also similar to a "refer all" strategy (100%) but had improved specificity (41% vs 0%).

CONCLUSIONS

Flow rate alone is insufficiently sensitive as a screening test to exclude BOO, but a simple diagnostic algorithm using age, flowrate, and PVR was more sensitive and accurate. This algorithm allows primary care evaluation and initial management of men with voiding symptoms while potentially reducing unnecessary referrals and costs.

Lack of correlation of the American Urological Association Symptom 7 Index with urodynamic bladder outlet obstruction

The objective of this study is to assess whether subjective information from the American Urological Association (AUA) Symptom 7 Index correlates with or predicts objective urodynamic parameters of bladder outlet obstruction. Seventy-five men, mean age 67 years (range 42-85 years), were referred for evaluation of "prostatism." Evaluation consisted of the AUA Symptom 7 Index, noninvasive uroflow, post-void residual (PVR) urine measurement, and pressure-flow analysis. Men were categorized as "obstructed," "equivocal," or "unobstructed" according to pressure-flow nomogram of Abrams and Griffiths. The total AUA 7 score, and all individual components, were compared with all invasive urodynamic parameters, and to the pressure-flow categories of obstructed, equivocal, or unobstructed. The AUA index severity categories (mild 0-7, moderate 8-19, and severe > or = 20) were compared to the urodynamic pressure flow categories. Thirty-three men had severe symptoms, and 42 had moderate or mild symptoms. Forty men were urodynamically obstructed, and 35 men were equivocal or unobstructed. There was no correlation of any AUA index parameter (total symptom score, obstructive or irritative score component, or any individual question) with any noninvasive urodynamic parameter. The sensitivity and specificity of the AUA index for urodynamic obstruction was 42.5% and 54.3% respectively. Multivariable logistic regression analysis was used to determine whether clinical data easily obtained in the office setting (age, PVR, noninvasive maximum and average flow rates) could predict urodynamic obstruction when combined with any component of the AUA index. Only age was found to be a significant predictor of obstruction status (P = 0.026). Subjective information from the AUA Symptom 7 Index does not correlate with objective data assessing bladder outlet obstruction. Though the AUA index is a valid clinical tool, it should not be used to gauge the presence or severity of bladder outlet obstruction.

Structural basis of geriatric voiding dysfunction. IV. Bladder outlet obstruction

Several aspects of the pathogenesis of voiding dysfunction in bladder outlet obstruction remain unresolved. The structural basis of obstructive versus nonobstructive dysfunction was investigated in a prospective ultrastructural/urodynamic study of 35 elderly subjects of comparable age. Detrusor structure was examined by electron microscopy, with blinded clinical and urodynamic information. Seven detrusor specimens were segregated by a distinctive myohypertrophy, structural pattern, which matched with 6 male and 1 female subjects 72 to 96 years old (mean age 83) who had urodynamically proved outlet obstruction. This pattern was characterized by widely separated muscle cells with reduction of intermediate cell junctions, collagenosis, that is abundant collagen plus some elastic fibers, in the markedly widened spaces between individual muscle cells and abundant profiles characteristic of enlarged, hypertrophic muscle cells. Superimposed degeneration of muscle cells and axons in 6 specimens matched those of 5 men and 1 woman who had impaired detrusor contractility. In 3 specimens there were also abundant protrusion junctions and ultra-close abutments; these matched those of 2 men and 1 woman with obstruction plus detrusor overactivity. Observations on the degree of bladder trabeculation in the entire population of 35 subjects are presented. It is concluded that bladder outlet obstruction is associated with changes in detrusor structure that can account for the resultant voiding dysfunction. Features of the myohypertrophy pattern, with or without superimposed degeneration, can explain overall weakness of the obstructed detrusor despite hypertrophy of its cells. Protrusion junctions and abutments probably mediate electrical coupling of muscle cells leading to involuntary contractions in the overactive (unstable) obstructed detrusor. Excessive deposits of elastic fibers (hyperelastosis) between widely separated muscle cells and in interstitium are suggested as the probable structural basis for increased bladder distensibility and chronic retention.

Bladder Wall Histology and Duration of Obstruction

In BPH patients, obstruction leads to a progressive modification in the structure of the bladder wall, with histo-pathological changes which are often irreversible. In order to detect these changes and their possible correlation with function, muscle biopsies of the bladder were taken from 28 patients during endoscopic resection for benign prostatic hyperplasia. The samples were examined by means of electron microscope to show ultrastructural charges. The magnitude of the lesions can be correlated to function, seriousness and duration of the obstruction. Detecting histo-pathological damage can justify earlier treatment in obstructed BPH patients, in order to avoid those bladder lesions, which are the probable cause of clinical disorders which may persist even after therapy of the adenoma.

Medical management of benign prostatic hyperplasia

Medical management of clinical BPH is a reality. The only effective nonsurgical treatment now recommended is aimed at relieving the dynamic component of clinical BPH. Pharmacologic treatment using alpha-adrenoceptor antagonists may be used appropriately to manage patients with prostatism who are poor surgical risks but who could benefit from reduced sympathetic tone. In addition, alpha blockers are used to relieve acute retention, and to prevent retention when increased sympathetic discharge is expected. Thus far, nonsurgical therapy aimed at reducing the mechanical obstruction associated with BPH by prostatic size reduction has failed to produce consistent objective improvement. However, several drugs are now being investigated and may be effective for reducing prostatic size in patients with BPH. Clinical trials are complicated by a number of factors, especially very variable symptoms. Moreover, reduction in prostatic size induced by drugs is not permanent and regrowth occurs with drug withdrawal, necessitating chronic treatment. Ideally, future research should be aimed at the prevention of BPH at an early age. However, this presupposes a better understanding of the pathogenesis of BPH. BPH may not be a single, variable disease but a family of diseases with a number of predictable clinical courses. In the future, we should pay particular attention to histologic variability, to see if in fact different pathologic forms of BPH follow different clinical patterns. If urologists are to keep their predominant position in managing the patient with BPH, they will have to keep informed of medical treatment trials and of potential alternative treatment strategies to prostatectomy.