[The urodynamic nomogram in defining various levels of obstruction in patients with benign prostatic enlargement (part I)].

AIM To determine matching degrees of urodynamic obstruction among available nomograms in patients with confirmed benign prostatic enlargement (BPE). SAMPLE AND METHODOLOGY 102 patients with confirmed BPE underwent a complete urodynamic investigation (uroflowmetry, cystometry and pressure/flow study). All the measurements were based on definitions adopted by the International Continence Society. Basic urodynamic data were then manually plotted on the Abrams-Griffiths, URA, ICS and Schafer (LinPURR) nomograms; A/G number was calculated as well. RESULTS Patients were allocated in the three levels of obstruction by Schafer's nomogram; 24 patients (23.5%) had no obstruction, 28 patients (27.4%) had equivocal or non-defined obstruction, while 50 patients (49.1%) had a significant level of obstruction. Spearman rank correlation coefficient has shown a rather uniform correlation of all nomograms. The correlation between Shafer's nomogram and ICS nomogram is the best one, with rho = 0.89 (p < 0.00001), which is followed by correlations between ICS and A/G nomograms with rho = 0.88 (p < 0.00001) and Schafer and A/G with rho = 0.87 (p < 0.00001). URA nomogram and A/G number have a similar correlation of r = 0.87 (p < 0.00001). According to the levels of obstruction, there is a good correlation in the zone of clear obstruction, as well in the zone out of obstruction among available nomograms (chi 2 test, p > 0.05) (URA has not been subject to this process). However, the above nomograms have shown a significant difference in figures relating to the unclassified zone of obstruction (chi 2 test; p < 0.05). CONCLUSION Despite a very high degree of correlation among individual nomograms, there are considerable differences in figures relating to the unclassified zone of obstruction. This zone should, therefore, be avoided by establishing an optimum model of clear obstruction defining.