title: Tissue viability measurement by in situ fluorometry.
abstract: A prototype laser-fiber optic based sensor for in situ monitoring of nicotinamide adenine dinucleotide (NADH) has been developed. This system is based on a compact neodymium-yttrium-aluminum-garnet (Nd:YAG) laser with associated harmonic generators. Light distribution to and from tissue is handled by a fiber optic network, including a long optical fiber to be inserted into the target tissue. Immobilizing the enzyme lactate dehydrogenase on the fiber tip converts the monitoring channel into a lactate sensor. A new dual beam reflection approach for blood volume artifact compensation is tested. Detection sensitivity of free NADH in the micromolar region is achieved. The method and system configuration appear feasible for continuous in situ monitoring of two important indices of ischemia and hypoxia in a clinical setting.
authors.affiliation: Biomedical Engineering Program, University of Texas Southwestern Medical Center, Dallas 75235-9031.
authors.forename: C S
authors.initials: CS
authors.lastname: Orr
authors.forename: S C
authors.initials: SC
authors.lastname: Arthurs
mesh_terms: D000818:Animals; D001698:Biomedical Engineering; D005069:Evaluation Studies as Topic; D005470:Fluorometry / Q000295:instrumentation* / Q000706:statistics & numerical data; D000860:Hypoxia / Q000175:diagnosis / Q000378:metabolism; D066298:In Vitro Techniques; D007511:Ischemia / Q000175:diagnosis / Q000378:metabolism; D007773:Lactates / Q000378:metabolism; D019344:Lactic Acid; D007834:Lasers; D008099:Liver / Q000378:metabolism; D009243:NAD / Q000378:metabolism*; D051381:Rats; D012680:Sensitivity and Specificity
chemical_list: D007773:Lactates; D009243:NAD; D019344:Lactic Acid