[Obstruction of the lower urinary tract: contractile capacity of the detrusor and obstruction degree. Analysis of pressure/flow curves].

OBJECTIVES

This study attempts to optimize information from pressure/flow curves of patients with obstructive symptoms.

METHODS

We performed a computerized analysis of the pressure/flow ratio of 50 consecutive patients with benign prostatic hyperplasia and irritative and obstructive symptoms. All patients were evaluated urodynamically. This model (pressure/flow diagram) will allow application of this test (expressed as flow and pressure measurements) to urethral outflow resistance and detrusor power or energy. Outflow obstruction is classified into seven categories (O-VI) and detrusor contractility in four (very weak, weak, normal and strong).

RESULTS

The suitability of urodynamic analysis was demonstrated. Those cases considered as indeterminate by the conventional method can be obviated by computerized analysis. The degree of obstruction and the contractile capacity were determined in these cases.

CONCLUSIONS

This method provides more accurate information on pathophysiology of voiding, allowing for better diagnosis of outflow obstruction or poor detrusor contractility and avoids the diagnosis of "undetermined".