Noninvasive Blood Glucose Monitoring With Optical Coherence Tomography
A pilot study in human subjects
- Kirill V. Larin, PHD123,
- Mohsen S. Eledrisi, MD4,
- Massoud Motamedi, PHD2 and
- Rinat O. Esenaliev, PHD1235
- 1Laboratory for Optical Sensing and Monitoring, University of Texas Medical Branch, Galveston, Texas
- 2Center for Biomedical Engineering, University of Texas Medical Branch, Galveston, Texas
- 3Department of Physiology and Biophysics, University of Texas Medical Branch, Galveston, Texas
- 4Department of Internal Medicine, University of Texas Medical Branch, Galveston, Texas
- 5Department of Anesthesiology, University of Texas Medical Branch, Galveston, Texas
OBJECTIVE—To study the feasibility of noninvasive blood glucose monitoring using optical coherence tomography (OCT) technique in healthy volunteers.
RESEARCH DESIGN AND METHODS—An OCT system with the wavelength of 1,300 nm was used in 15 healthy subjects in 18 clinical experiments. Standard oral glucose tolerance tests were performed to induce changes in blood glucose concentration. Blood samples were taken from the right arm vein every 5 or 15 min. OCT images were taken every 10–20 s from the left forearm over a total period of 3 h. The slope of the signals was calculated at the depth of 200–600 μm from the skin surface.
RESULTS—A total of 426 blood samples and 8,437 OCT images and signals were collected and analyzed in these experiments. There was a good correlation between changes in the slope of noninvasively measured OCT signals and blood glucose concentrations throughout the duration of the experiments. The slope of OCT signals changed significantly (up to 2.8% per 10 mg/dl) with variation of plasma glucose values. The good correlation obtained between the OCT signal slope and blood glucose concentration is due to the coherent detection of backscattered photons, which allows measurements of OCT signal from a specific tissue layer without unwanted signal from other tissue layers.
CONCLUSIONS—This pilot study demonstrated the capability of the OCT technique to monitor blood glucose concentration noninvasively in human subjects. Further studies with a larger number of subjects including diabetic subjects are planned to validate these preliminary results.
- 1-D, one-dimensional
- 2-D, two-dimensional
- ISF, interstitial fluid
- NIR, near-infrared
- OCT, optical coherence tomography
- OGTT, oral glucose tolerance test
- PC, personal computer
- SMBG, self-monitoring of blood glucose
Address correspondence and reprint requests to Rinat O. Esenaliev, PhD, Associate Professor, Director of Laboratory for Optical Sensing and Monitoring, Center for Biomedical Engineering, University of Texas Medical Branch, 301 University Blvd., MS 0456, Galveston, TX 77555-0456. E-mail:.
Received for publication 31 January 2002 and accepted in revised form 5 September 2002.
A table elsewhere in this issue shows conventional and Système International (SI) units and conversion factors for many substances.
- DIABETES CARE