Voiding efficiency and urodynamic parameters in pediatric patients with posterior urethral valves

To describe the differences between voiding efficiency (VE) and other parameters of non-invasive urodynamic studies between patients with a history of posterior urethral valves (PUV) and patients without anatomical alterations of the lower urinary tract.

A retrospective case-control study was carried out from 2012 to 2022. Cases with a PUV history and controls without anatomical urethral alterations were included. Clinical variables, classic urodynamic parameters, lag time, and VE were collected. Student's t-test, Mann-Whitney U test, and Kruskal-Wallis' test were used to compare quantitative variables, whereas the chi-squared test was employed to compare qualitative variables.

N= 100 (n= 50 cases and n= 50 controls). Age: 7.8 ± 3.73 years. The case group had greater postvoiding residual volume (9 ml vs. 3 ml; p= 0.025) and a longer lag time (3.7 ± 5.41 s vs. 2.6 ± 1.80 s; p= 0.006), as well as less VE (93.8% vs. 98%; p= 0.020), than the control group.

In patients with a history of PUV, alterations in urodynamic studies were more frequent than in controls. Voiding efficiency is an easily measurable urodynamic parameter that has not been implemented in regular practice in pediatric patients yet. Our data demonstrates that VE can be lower in PUV patients than in patients without anatomical urethral alterations.