Hybrid diffuse optical techniques for continuous hemodynamic measurement in gastrocnemius during plantar flexion exercise.

TitleHybrid diffuse optical techniques for continuous hemodynamic measurement in gastrocnemius during plantar flexion exercise.
Publication TypeJournal Article
Year of Publication2015
AuthorsHenry B, Zhao M, Shang Y, Uhl TL, D Thomas T, Xenos ES, Saha S, Yu G
JournalJ Biomed Opt
Volume20
Issue12
Pagination125006
Date Published2015
ISSN1560-2281
KeywordsAdult, Algorithms, Blood Flow Velocity, Calibration, Exercise, Female, Healthy Volunteers, Hemodynamics, Hemoglobins, Humans, Isometric Contraction, Lower Extremity, Male, Muscle, Skeletal, Optics and Photonics, Oxygen, Oxygen Consumption
Abstract

Occlusion calibrations and gating techniques have been recently applied by our laboratory for continuous and absolute diffuse optical measurements of forearm muscle hemodynamics during handgrip exercises. The translation of these techniques from the forearm to the lower limb is the goal of this study as various diseases preferentially affect muscles in the lower extremity. This study adapted a hybrid near-infrared spectroscopy and diffuse correlation spectroscopy system with a gating algorithm to continuously quantify hemodynamic responses of medial gastrocnemius during plantar flexion exercises in 10 healthy subjects. The outcomes from optical measurement include oxy-, deoxy-, and total hemoglobin concentrations, blood oxygen saturation, and relative changes in blood flow (rBF) and oxygen consumption rate (rV̇O2). We calibrated rBF and rV̇O2 profiles with absolute baseline values of BF and V̇O2 obtained by venous and arterial occlusions, respectively. Results from this investigation were comparable to values from similar studies. Additionally, significant correlation was observed between resting local muscle BF measured by the optical technique and whole limb BF measured concurrently by a strain gauge venous plethysmography. The extensive hemodynamic and metabolic profiles during exercise will allow for future comparison studies to investigate the diagnostic value of hybrid technologies in muscles affected by disease.

DOI10.1117/1.JBO.20.12.125006
Alternate JournalJ Biomed Opt
PubMed ID26720871
PubMed Central IDPMC4688865
Grant ListR21 AG034279 / AG / NIA NIH HHS / United States
R21 AG046762 / AG / NIA NIH HHS / United States
R21-AG034279 / AG / NIA NIH HHS / United States
R21-AG046762 / AG / NIA NIH HHS / United States