Reproducibility of pressure-flow variables in patients with symptomatic benign prostatic hyperplasia

Development of Urodynamic Standards for Quality Control

“…In the interpretable pressure-flow traces, Q max , urethral resistance (OCO), grading and classifying of obstruction underwent significant systematic changes; P det.Qmax had no systematically significant changes, but with considerable intra-individual changes after manual correction. Q max reduced consistently by 1.17 ml/ sec on average, which was similar to the result (by 1.5 ml/ sec on average) reported by Grino et al in 1645 uroflow measurements and the result (by 0.8 ml/ sec on average) reported by Madsen et al in pressure-flow studies of 25 patients (Grino et al 1993;Madsen et al 1995). In this study, 81.8% traces showed obvious artifacts of Q max .…”

“…Grino et al compared manual and automated values, and found consistently lower values of Q max in manual readings (Grino et al 1993). Madsen et al compared manual and computerized values of Q max and detrusor pressure at Q max (P det.Qmax ) in a small group of patients, and found some different pressure-flow results between manual and computerized groups (Madsen et al 1995). From these views, quality control in retrospective data analysis is necessary.…”

“…P det.Qmax showed a slight systematic increase by 0.75 cmH 2 O on average after manual correction, but no significant variation was demonstrated. Similarly, Madsen et al reported a no significant slight decrease of P det.Qmax , with a mean of 2.8 cmH 2 O after correction (Madsen et al 1995). The reason would be that the location of P det.Qmax responds to Q max ; therefore, intra-individual changes of P det.Qmax were inconsistent.…”

Electrovaporization of the Prostate versus Laser Ablation of the Prostate in Men with Benign Prostatic Hypertrophy:A Pressure-Flow Analysis

“…It would appear that there was no improvement from a pressure-flow viewpoint based on these data. However, Madsen et al [10] recently reported that of the patients who underwent consecutive pressure-flow studies, 28% had variability in results that would change their classification based on the AbramsGriffin nomogram. The above findings lead to debate on whether a single pressure-flow study performed preoperatively or postoperatively is adequate in delineation of the pressure-flow classification according to the AbramsGriffin nomogram.…”

The role of urodynamics in the diagnosis and treatment of benign prostatic hyperplasia

“…Two or three consecutive studies must be performed because the results of a single test are highly variable [19]. There tends to be a decrease in obstructive parameters with successive tests so that as many as 28% of patients will be redefined into a less obstructive AbramsGriffiths category if the first study is compared with subsequent studies [20,21]. Furthermore, interpretation of the tests is not always straightforward, resulting in a high intra-and inter-interpreter variability [22].…”