Prognostic value of a combination of IPSS, flow rate and residual urine volume compared to pressure-flow studies in the preoperative evaluation of symptomatic BPH.

OBJECTIVE: Evaluate the predictive value of a combination of IPSS, uroflowmetry and ultrasound determination of residual urine volume in the determination of bladder outflow obstruction (BOO) and in predicting treatment outcome.

METHODS: Forty-five out of a group of 60 BPH symptomatic patients were included. Preoperative evaluation: urine culture, PSA, uroflowmetry with sonographic measurement of post-void residual urine, DRE, IPSS with quality of life questions and pressure-flow study. Selection criteria for surgery were IPSS > 16 and Qmax < 10 ml/s. Transurethral resection of the prostate was performed in these patients; the control visit was performed at 3 months. Treatment success was defined as Qmax above 15 ml/s, residual urine of less than 100 ml, a 50% reduction in IPSS and absence of urinary retention.

RESULTS: Urodynamic abnormalities were found in 42 patients (93.3%): 19 had detrusor instability, 5 patients showed impaired contractility, 37 patients had proven BOO, and 8 patients were unobstructed or mildly obstructed. The overall success rate was 86% when measured by the IPSS. Its preoperative value was 16.9, and dropped significantly to 4 (P = 0.005). The score improved significantly after surgery only in the obstructed group compared to the non-obstructed group (P = 0.001), however preoperative IPSS did not correlate with objective treatment results.

CONCLUSIONS: A high proportion of patients successfully operated (71.1%) had a combination of IPSS > 16 and Qmax < 10 ml/s, although BOO could not be accurately predicted with non-invasive methods alone. Patients with no or mild infravesical obstruction had only minimal improvement of IPSS and uroflowmetry following surgery.