Back to 2014 Fall Congress Meeting Posters

Urodynamic differences between bell shaped and non-bell shaped uroflow patterns among dysfunctional voiders - a new categorization
Lesli Nicolay, MD, Jordan Gitlin, MD, Lane S. Palmer, MD.
Cohen Children's Medical Center of New York, Lake Success, NY, USA.

BACKGROUND: Dysfunctional voiding (DV) is defined as the presence of external sphincter activity, as measured by EMG, during the voiding phase. While ICCS defines DV as the presence of a staccato uroflow pattern, other patterns, including a bell curve may be present with documented pelvic floor activity. The purpose of this study is to better understand whether uroflow curve patterns can provide further insight into the voiding characteristics of children with DV.

We reviewed the diagnostic EMG-uroflow studies of the last 61 children presenting with symptoms of DV in our practice. The studies were obtained at the time of initial diagnosis and prior to any treatment (behavioral, etc). Patch EMGs were performed and the uroflow started with a bladder volume of 50-75% of age-expected bladder capacity. The flow curve pattern was categorized as either bell shaped or non-bell shaped (staccato, plateau). The uroflow parameters Qmax, Qmean, flow time, time to Qmax, and the percent of PVR were compared between the two groups. Bladder volume and PVR were measured by ultrasound. Data were analyzed by two-tailed t-test (p< 0.05).

All 61 children (55 females, 6 males) had EMG activity during voiding - DV. Twenty-nine children (26 females, 3 males) demonstrated bell uroflows and 32 children (29 females, 3 males) had non-bell uroflows. Patients with bell uroflows demonstrated significantly greater Qmean and lower flow time, time to max and %PVR. The Qmax among bell curved flows was greater and approached statistical significance (Table 1).

The difference between bell and non-bell shaped uroflow patterns correlates with differences in voiding parameters suggesting two categories of DV. Patients with a bell uroflow may represent bladders with an underlying compensatory mechanism enabling them to overcome the external sphincter
Comparison of voiding parameters for bell and non-bell groups
Voiding ParameterBell shapedNon-bell shapedp-value
Qmax (ml/s)2419.50.06
Qmean (ml/s)
Flow Time (s)15.922.90.003
Time to Qmax(s)6.913.40.01
% PVR8.755.10.01

Back to 2014 Fall Congress Meeting Posters
© 2020 The Society for Pediatric Urology. All Rights Reserved.
Read Privacy Policy.