Presentation Authors: Zachary Cullingsworth*, Adam Klausner, John Speich, Richmond, VA
Introduction: Detrusor overactivity (DO) is diagnosed based on the visual identification of isolated, sporadic or periodic non-voiding contractions in pressure data from urodynamics (UD) studies. In some patients, spontaneous rhythmic contractions (SRC) contribute to overactive bladder. The aim of this study was to develop an algorithm to objectively identify and quantify SRC using UD filling data and determine whether the group participants identified with significant SRC correlated with the group of participants identified with phasic DO.
Methods: Adults with non-neurogenic overactive bladder were prospectively enrolled in an IRB-approved urodynamics protocol. Analysis of UD data from 23 participants was performed using an automated fast Fourier transform (FFT) algorithm. Low volume and high volume (first 265 seconds of filling and 265 seconds immediately prior to void, respectively) regions were analyzed to identify the three largest rhythmic amplitude peaks in vesical pressure (Pves) at frequencies in the 1.75-6 cycle/minute range. Any &[Prime]significant&[Prime] rhythmic activity in Pves was identified and analyzed to determine if that activity was &[Prime]independent&[Prime] of any rhythmic activity in abdominal pressure (Pabd). For the participants with significant and independent (S&I) SRC, the frequencies and amplitudes of the rhythmic activity were quantified.
Results: A neurourologist performed a blinded analysis of UD pressure data and identified 14/23 participants as having DO, including six with phasic DO and eight with terminal DO. The automated algorithm identified S&I SRC in six participants, which were all identified as having DO. The group with S&I SRC included four of the six participants with phasic DO, and there was a significant association between the group identified with S&I SRC by the algorithm and the group with phasic DO (Fischer&[prime]s exact test, p=0.02). For the group of six participants identified with S&I SRC, the average slowest significant frequency was 2.2±0.2 cycles/min and the corresponding average amplitude was 5.2Â±1.6 cm-H2O.
Conclusions: This study demonstrated the effectiveness of an automated algorithm designed to objectively quantify frequencies and amplitudes of spontaneous rhythmic bladder contractions during urodynamic filling. Characterization of rhythmic contractions may provide valuable metrics to quantify the severity of DO and the effectiveness of DO treatments.
Source of Funding: This study was supported by National Institutes of Health award R01DK101719.