Measurement of exercise treatment effect from pelvic floor muscle therapy for lower urinary tract dysfunction using near infrared spectroscopy


Background: In sports medicine, near infrared spectroscopy (NIRS) is used to measure physiologic parameters of muscle function, and quantify the effects of exercise. Firstline treatment for urinary incontinence (UI) involves pelvic floor muscle (PFM) rehabilitation therapy (PFMT), but currently oxygen kinetic measures to quantify training effect are lacking. Methods: Half-recovery time of hemoglobin difference, HbDiff(½RT), following sustained maximal voluntary contraction (SMVC), is a validated, NIRS-derived, oxygen kinetic parameter used in exercise science and healthcare monitoring, shown previously to be applicable to the PFM in healthy women using a transvaginal NIRS interface. We evaluated if a PFMT training effect could be detected using HbDiff(½RT) measurement in symptomatic women with UI. Results: HbDiff(½RT) data sets were obtained from 7 symptomatic women prior to and following an 8-week, homebased PFMT regimen; these were compared in each individual and with data from 11 asymptomatic controls. A post training treatment effect was evident where HbDiff(½RT) shortened, indicating improved PFM metabolic function. Discussion: PFM NIRS monitoring proved feasible in a heterogeneous group of women with UI, provided a quantifiable kinetic parameter, and proved more comfortable than conventional perineal pressure measurements (perineometry). Importantly, in one subject with UI due to an incomplete spinal cord lesion, and no detectable PFM contractile ability on initial assessment, NIRS enabled a post-PFMT improvement to be detected using PFM oxygen kinetics. Conclusions: Calculation of HbDiff(½RT) following PFM SMVC allows a validated muscle reoxygenation parameter to be applied in evaluation of PFM dysfunction, and to measure training effect from rehabilitation exercise, potentially improving management of UI.

Biophotonics in Exercise Science, Sports Medicine, Health Monitoring Technologies, and Wearables II