[The study on the effect of the transurethral catheter in pressure-flow study--the comparison with the urination in uroflowmetry].

OBJECTIVE: Pressure-flow study (PFS) is an excellent method for detecting the bladder outlet obstruction. However, PFS with the transurethral catheter has the disadvantage of unphysiological urination during testing. In the present study, we compared the urination in PFS with that in uroflowmetry (UFM) and analyzed the effect of the transurethral catheter. MATERIALS AND METHODS: The subjects were 43 men who underwent PFS at Yamato Takada Municipal Hospital. PFS and UFM were compared with respect to four parameters, i.e., Qmax, the residual urine volume, the region on Liverpool nomogram, and the flow curve pattern (Jorgensen's classification). RESULTS: For PFS using a transurethral catheter, (1) Qmax was decreased by a mean of 2.6 ml/s and the residual urine volume was increased by a mean of 26.3 ml compared with UFM, and (2) the Liverpool nomogram and the flow curve pattern showed more impairment of urination with PFS than UFM. CONCLUSION: It is suggested that PFS using a transurethral catheter may not reflect physiological urination.