Objective    To investigate the significance of uroflowmetry combined with ultrasonic residual urine in evaluation of detrusor function in the patients with benign prostate hyperplasia (BPH).      Methods    Non-invasive detrusor contractile studies (NIDCS) including uroflowmetry and ultrasonic residual urine measurement and invasive pressure-flow studies (IPFS) were performed on 150 patients with BPH. Detrusor function was graded into 3 groups

detrusor overactivity

underactivity and normal according to flow curve shape

maxi

mum flow rate and residual urine. The results from both urodynamic studies were compared using Chi-square test.     Results     In NIDCS

90 patients were verified with detrusor overactivity

34 with detrusor underactivity and 26 with detrusor normal. In IPFS

100 patients belonged to detrusor overactivity

20 to detrusor underactivity and 30 to patients detrusor normal. There was no significant difference of detrusor activities diagnosis between NIDCS and IPFS (

P

=0.109). The sensitivity

specificity

accuracy of NIDCS were 75%

70%

and 73% respectively in diagnosis of detrusor overactivity

and 80%

86% and 86% for detrusor underactivity.     Conclusion    Compared with IPFS

NIDCS is also a useful approach in evaluation of detrusor function in patient with BPH.