Fig 1.
Example multichannel urodynamics output for Pves, Pabd, detrusor pressure (Pdet = Pves—Pabd), infused volume (VH2O), voided volume (volume) and void flow rate (flow).
Table 1.
P-values showing no significant association between Male vs. Female and NDO vs. IDO (Fisher’s exact test), and no significant difference in ages of S&I and DO vs. Others (t-test).
Fig 2.
Flowchart for the FFT LARC algorithm.
(A) UDS volume data showing time ROI. (B & C) raw and smoothed Pves and Pabd data from the time ROI. (C dashed) Model of an ideal sine wave with a frequency of 2.05 cycles/min and a peak-to-peak amplitude of 17.12 cm-H2O, derived from the FFT results in panel F. The model peak-to-peak amplitude is 4 times the FFT output amplitude due to a factor of 2 from the FFT windowing and factor of 2 due to the two halves of the sine wave. (D) FFT of Pves and Pabd from the ROI with the 1.75–6 cycle/min frequency range of interest shaded. (E) gray shaded region from panel D for Pves1 with range of neighboring points shaded orange. (F) Significance test: Pves1 is a sharp “significant” peak if J and/or K, and L and/or M are within the red region and if Pves1 > 0.45. (G) Independence test: a significant Pves1 peak is “independent” of Pabd1 if Pabd1 is relatively flat compared to points Q & R (within the red region below 133% of the max of Q & R) and if Pves1 > 150% of Pabd1 (F & G).
Fig 3.
Examples of pressure tracings and corresponding FFT results.
(A) Example Pves and Pabd tracings for an entire UDS fill illustrating the 3 ROIs analyzed in this study. (B) Pves and Pabd data for 205 seconds of filling illustrating the “30s prior to void” ROI with an overlaid sine wave model (dashed) derived from the FFT results in panel D. (C) FFT of Pves and Pabd for the entire fill from panel A, demonstrating an increased frequency resolution (smaller spacing between the points) compared to (D), the FFT for the 205 second region in panel B with the frequency resolution used throughout this study. “S” indicates a significant Pves peak that was not independent of Pabd and “S&I” indicates a significant Pves peak independent of any corresponding Pabd peak.
Table 2.
Algorithm sensitivities and specificities.
P-values showing significant association between S&I and DO (Fisher’s exact).
Fig 4.
(A) Example Pves and Pabd tracings for the final 205s of a UDS fill showing translated abdominal events and (B) the corresponding FFT output. “S” indicates a significant Pves peak that was not independent of Pabd. (C) Example Pves, Pabd and Pdet tracings for the final 205s of a UDS fill illustrating abdominal event that was not translated to Pves but appears in Pdet, and (D) the corresponding FFT output.
Fig 5.
(A) Example of a UDS pressure data with Pabd and Pves not equalized (cough at ~1.3 min) (B) corresponding infused (VH2O) and voided volumes. (C) Pves and Pabd from the ROI (shaded region in A & B) and corresponding sine wave model (dashed) derived from FFT results in panel D. (D) FFT results of the ROI in panel C.