Criteria for differentiation of normal and abnormal uroflowmetrograms in adult men.

Objective: To study parameters which serve as criteria for differentiation of normal and abnormal uroflowmetrograms.

Subjects And Methods: A total of 105 subjects were investigated, 43 of whom had no symptoms of dysuria, 57 of whom had dysuria demonstrated as an abnormal uroflowmetrogram, subjective symptoms and a small residual urine volume, and five patients who were about to undergo transurethral resection of the prostate. The three parameters used to specify the shapes of the uroflowmetrogram curves were: (i) the ratio of the maximum flow rate (Qmax) and the voiding time (T100), Qmax/T100; (ii) the ratio of the time to peak flow (TQmax) and the voiding time, TQmax/T100; and (iii) the newly introduced voiding efficiency (epsilon), measured by the ratio of the voided volume (VV) and T100 x Qmax, epsilon = VV/(T100 x Qmax), were taken for each patient.

Results: The criteria for normal uroflowmetrograms were: Qmax/T100 > or = 0.78, 0.32 < or = TQmax/T100 < or = 0.54, 0.63 < or = epsilon < 1, respectively. In the patients who underwent transurethral resection of the prostate the values of all three parameters improved and returned almost to normal after operation.

Conclusion: Using these three parameters the micturition pattern can be expressed quantitatively.