PREOPERATIVE CYSTOMETROGRAPHY IN PATIENTS WITH CLINICAL BENIGN PROSTATIC HYPERTROPHY

Preoperative water cystometrograms obtained from 437 patients with ben ign prostatic hyperplasia (BPH) were examined in a retrospective study . The cystometrographic results were analyzed regarding the preoperati ve clinical features: the patients' age, presence or absence of urinar y incontinence, history of urinary retention, and rate of residual uri ne. Their prognostic value in terms of improvement in voiding difficul ty and postoperative urinary incontinence was also analyzed at 1 and 6 months after elective transurethral resection of the prostate (TURP). Of these patients, 263 (60.2%) had detrusor instability (group I), wh ereas 174 did not (group II). Vesical denervation supersensitivity (Vd s) to bethanecol chloride was noted in 47 (12.5%) of 375 patients. The observed difference in clinical features was significant between the two groups, with group I being older (P < 0.01) and showing a greater incidence of urinary incontinence (P < 0.001) and retention (P < 0.001 ). The difference seen between groups I and II in terms of mean bladde r capacity (P < 0.01), compliance (P < 0.01), and a greater positive r ate of Vds (P < 0.001) was also significant. The clinical and cystomet rographic parameters studied worsened with advancing age of the patien ts. Although the majority of the patients (94.7%) were relieved of obs tructive symptoms after TURP (6 months later), 113 (25.9%) showed no r elief at 1 month. As compared with the 324 early improvers (74.1%), no nimprovers at 1 month were characterized by a higher age (P < 0.01), a higher prevalence of preoperative incontinence (P < 0.05) and retenti on (P < 0.01), a higher residual urine rate (P < 0.05), a less complia nt bladder (P < 0.01), and a higher positive rate of Vds (P < 0.05). T he cystometrographic findings, however, had no relevance to the late ( 6 months) outcome of voiding difficulty. On the other hand, postoperat ive incontinence was noted in 100 patients (22.9%) at 1 month after TU RP, the majority of whom were afflicted with similar preoperative epis odes (70.0%) and detrusor instability (87.0%). They were also older (P < 0.01) and had a less compliant bladder (P < 0.01) and a higher posi tive rate of Vds (P < 0.01) than did continent patients. Only 18 elder ly patients (4.1%), however, remained incontinent 6 months later, all of whom initially had a less compliant (P < 0.01) and more unstable bl adder (P < 0.01). The genesis of this detrusor dysfunction was conject ured to be a function of aging in men whereby BPH evolves and progress es. In conclusion, preoperative cystometrography in patients with BPH is valuable in that (1) it correlates well with the clinical features and (2) it can predict to some extent the outcome of obstructive sympt oms and urinary incontinence after TURP.