Share Email Print

Proceedings Paper

In-vivo determination of myocardial pH during regional ischemia using near-infrared spectroscopy
Author(s): Songbiao Zhang; Babs R. Soller
Format Member Price Non-Member Price
PDF $17.00 $21.00

Paper Abstract

pH electrodes have been used during open heart surgery to ensure adequate delivery of blood and oxygen to the myocardium during the surgical procedure. The electrodes are cumbersome and suffer from motion artifacts. Near infrared spectroscopy was evaluated as a noninvasive method of measuring myocardial pH during regional ischemia in seven beating dog hearts. Two pH microelectrodes were implanted in the distribution area of the left anterior descending (LAD) coronary artery. The LAD was occluded to stop the myocardial blood flow and to initialize regional ischemia. Ischemia was maintained for 20 minutes before the LAD was released to resume blood flow. A fiber-optic probe was used to collect the reflected NIR light over the spectral region of 575 nm to 1100 nm from the heart muscle. Partial least-squares multivariate calibration technique was applied to relate the myocardial pH changes to the NIR spectral changes in the region of 700 to 1100 nm. Calibration models based on data collected on each individual dog heart had an average of 7 factors with an R2 of 0.84. The standard error of prediction (SEP) averaged 0.09 pH units for a mean pH change of 0.73 pH units, adequate for monitoring pH changes during cardiac surgery.

Paper Details

Date Published: 24 April 1998
PDF: 8 pages
Proc. SPIE 3257, Infrared Spectroscopy: New Tool in Medicine, (24 April 1998); doi: 10.1117/12.306076
Show Author Affiliations
Songbiao Zhang, Univ. of Massachusetts Medical Ctr. (United States)
Babs R. Soller, Univ. of Massachusetts Medical Ctr. (United States)

Published in SPIE Proceedings Vol. 3257:
Infrared Spectroscopy: New Tool in Medicine
Henry H. Mantsch; Michael Jackson, Editor(s)

© SPIE. Terms of Use
Back to Top
Sign in to read the full article
Create a free SPIE account to get access to
premium articles and original research
Forgot your username?