Does the degree of bladder outlet obstruction (BOO) correlate with the postoperative results of patients undergoing surgical treatment for benign prostatic enlargement (BPE)?
Strong evidence suggests that patients with BOO have greater overall improvement after surgical treatment for BPE, compared to patients without BOO. But, do patients with BOO have greater improvement as the obstruction increases? We aim to determine the differences in patients who underwent photovaporization of the prostate (PVP) with GreenLight 180W XPS according to their degree of BOO.
Patients who underwent PVP between 2012 and 2017 with available urodynamic study were included. BOO index (BOOI) was categorized into 40-100 (mild/moderate obstruction) and ≥100 (severe obstruction); patients with BOOI<40 (equivocal/unobstructed) were included as a reference group. Postoperative complications and effectiveness outcomes were reported. Descriptive and inferential statistics were employed.</p>
We included 382 patients: 63% with BOOI 40-100 and 8% BOOI≥100; the rest had BOOI<40. Table 1 shows pre-, intra- and postoperative characteristics; no differences were found in the effectiveness outcomes between BOOI≥100 and 40-100. Pearson correlation coefficient between BOOI and post-IPSS was r=-0.22 (p=0.001). When we only included patients with BOOI>40, no correlation was found (r=-0.09, p=0.25). The multivariate logistic regression analysis found that age, previous acute urinary retention (AUR), Qmax<10 ml/s, PVR>300ml, BCI>150 and prostate volume >120mL were associated with BOOI>100 (Table 2).
Severely obstructed patients were younger, had larger prostates, lower Qmax, stronger detrusor contractility, higher PVR and were more likely to have previous AUR compared to patients with BOOI 40-100. There was a weak negative correlation between BOOI in any degree and post-IPSS, suggesting that as the BOOI increases, the post-IPSS decreases, but no correlation was found when we only included patients with BOOI>40. There seems to be no additional benefits in severely obstructed patients compared to the mild/moderately obstructed group.