Abstract
[Objective] This study aimed to verify whether the activity of the pelvic floor muscles can be monitored using a pressure sensor by measuring perineal pressure resistance values with a pressure sensor, bladder base elevation using transabdominal ultrasound imaging, and vaginal pressure with a vaginal pressure measuring device.
[Methods] The study included four healthy adult women (mean age: 53.0 ± 8.3 years) who provided informed consent. Measurements were conducted in a seated position using a chair equipped with a pressure sensor array consisting of 30 measurement points on the seat surface. The experiment was divided into two sessions: Experiment 1 measured pressure resistance values and bladder base elevation, while Experiment 2 measured pressure resistance values and vaginal pressure. Each session consisted of three sets, with participants alternately relaxing and contracting their pelvic floor muscles three times per set. The data were analyzed by comparing relaxation and contraction phases of pelvic floor muscle activity, and time-series graphs were assessed visually as well as using the Dynamic Time Warping (DTW) method.
[Results] Compared to the relaxation phase, the contraction phase showed an increase in both bladder base elevation and vaginal pressure. Additionally, the pressure resistance values exhibited a decompression waveform synchronized with pelvic floor muscle contraction. The time-series graphs of each measurement generally displayed similar waveforms. Furthermore, DTW analysis identified specific measurement points where the pressure resistance values showed waveform changes similar to those of vaginal pressure.
[Conclusion] The results suggest that changes in pressure resistance values obtained from the pressure sensor were largely synchronized with the time-series data of bladder base elevation and vaginal pressure, indicating the feasibility of monitoring pelvic floor muscle relaxation and contraction. Given the small sample size in this study, future research should include a larger and more diverse sample to enhance the validity of the findings. However, given the small sample size of four participants, further research with a larger and more diverse population is necessary.
