In both nondiabetic and diabetic patients, hyperglycemia and insulin resistance commonly complicate critical illness. Even moderate hyperglycemia, at levels that conventionally have not been treated acutely with insulin because of the risk of inducing hypoglycemia, contributes to morbidity and mortality. A recent randomized clinical trial in critically ill patients demonstrated that intensive insulin therapy to tightly control blood glucose concentration (80 - 110 mg/dL) substantially reduced morbidity and mortality by more than 40% (from 8.0% to 4.6%) but was associated with a 5.0% incidence of severe hypoglycemia (glucose concentration < 40 mg/dL). Therefore, in critically ill patients, continuous glucose monitoring, ideally noninvasive, would be invaluable to guide insulin infusion to both control hyperglycemia and avoid hypoglycemia. For this purpose, optical coherence tomography (OCT) based on low-coherence interferometry, a high-resolution optical technique that sensitively detects photons coherently scattered from tissue, is highly promising. We have developed a novel, OCT-based glucose sensor that precisely, continuously and noninvasively measures the decrease of tissue light scattering that linearly accompanies increases of blood glucose concentration. During the past two years, supported by an NIDDK R-21 grant under the PA-99-036 (""""""""Pilot and Feasibility Program in Diabetes Endocrinology and Metabolism""""""""), we performed preliminary animal and clinical studies of the novel glucose sensor. Our studies demonstrated: 1) a sharp and linear decrease of the OCT signal slope in skin and oral mucosa as blood glucose concentration increased; and 2) substantial improvement of accuracy of the OCT signal slope measurement by optimizing the dimensions of the probed tissue area. The goals of the proposed project are: (1) to further refine the glucose sensor in animal studies; and (2) to validate the resulting sensor in clinical studies in normal subjects and critically ill patients. Successful implementation of the project will produce a continuous, noninvasive, and accurate glucose sensor that will substantively contribute to reduced mortality and morbidity in critically ill patients.

Agency
National Institute of Health (NIH)
Institute
National Institute of Biomedical Imaging and Bioengineering (NIBIB)
Type
Research Project (R01)
Project #
1R01EB001467-01A1
Application #
6777760
Study Section
Special Emphasis Panel (ZRG1-BECM (01))
Program Officer
Pastel, Mary
Project Start
2004-03-01
Project End
2007-02-28
Budget Start
2004-03-01
Budget End
2005-02-28
Support Year
1
Fiscal Year
2004
Total Cost
$305,775
Indirect Cost
Name
University of Texas Medical Br Galveston
Department
Neurosciences
Type
Schools of Medicine
DUNS #
800771149
City
Galveston
State
TX
Country
United States
Zip Code
77555
Sapozhnikova, Veronika V; Kuranov, Roman V; Cicenaite, Inga et al. (2008) Effect on blood glucose monitoring of skin pressure exerted by an optical coherence tomography probe. J Biomed Opt 13:021112
National Institute of Biomedical Imaging and Bioengineering/National Heart, Lung, and Blood Institute/National Science Foundation Workshop Faculty; Price, Christopher P; Kricka, Larry J (2007) Improving healthcare accessibility through point-of-care technologies. Clin Chem 53:1665-75
Kuranov, Roman; Sapozhnikova, Veronika; Prough, Donald et al. (2007) Correlation between optical coherence tomography images and histology of pigskin. Appl Opt 46:1782-6
Kuranov, Roman V; Sapozhnikova, Veronika V; Prough, Donald S et al. (2006) In vivo study of glucose-induced changes in skin properties assessed with optical coherence tomography. Phys Med Biol 51:3885-900
Sapozhnikova, Veronika V; Prough, Donald; Kuranov, Roman V et al. (2006) Influence of osmolytes on in vivo glucose monitoring using optical coherence tomography. Exp Biol Med (Maywood) 231:1323-32