Qualitative quality control during urodynamic studies with TSPs for cystometry in men with lower urinary tract symptoms suggestive of benign prostatic hyperplasia.

The aim of this study was to describe typical signal patterns (TSPs) by amplitude and pressure gradients and indicate the role and significance of them in quality control. A total of 582 measurements from a multicenter urodynamic study on males (mean age, 65.3 years) were re-analyzed. Using manual graphical analysis, we identified signal patterns by typical amplitude (A) and typical pressure gradient (PG). TSPs were classified into four types: I: fine structure (A < 3 cm H2O); II: minor dynamic changes (A < 5 cm H2O); III: major changes due to cough tests (A > 50 cm H2O, PG > 100 cm H2O/s); IV: typical major changes due to muscular activity: detrusor overactivity (A > 3 cm H2O, PG > 1-5 cm H2O/s), rectal contractions (A = 5-10 cm H2O, PG = 5-10 cm H2O/s), and straining (A > 5 cm H2O, PG ≥ 30 cm H2O/s). At beginning of and during filling, 91.8 and 98.3 % of traces showed the identical fine structure and minor changes between P ves and P abd tracings, and P det tracing was quiet. 92.3 % of P ves and P abd traces had equal pressure changes at test coughs. During filling, 8.3 % traces showed straining, 17.4 % showed rectal contractions, and 33.7 % showed detrusor overactivity. Before voiding, 94 % of P ves and P abd traces had equal cough response. During voiding, 91.2 % of traces showed the same fine structure, 53.3 % of traces showed straining, and 15.3 % showed relaxation of the pelvic floor. After voiding, 91.2 % of traces had the same fine structure, and 87.5 % had an equal cough response. TSPs are a powerful tool for qualitative plausibility and quality control and are an indispensable pre-condition for good urodynamic practice.