Blood microcirculation monitoring by use of spatial filtering of time-integrated speckle patterns: potentialities to improve the depth resolution
Statistical analysis of images of time-integrated dynamic speckle patterns is considered as the tool for diagnostics and imaging of in vivo tissue dynamics such as blood microcirculation in superficia...
Helmet-mounted choroidal laser Doppler flowmeter
A compact laser Doppler flowmeter (35x80x210mm3) for the measurement of subfoveal choroidal blood flow parameters (ChBF) was mounted on a helmet. This device allows the measurement of ChBF during dyna...
Potential application of optical coherence tomography for noninvasive monitoring of glucose concentration
Proc. SPIE, Vol. 4263, 83 (2001);
doi:10.1117/12.429342
Online Publication Date: 30 April 2003
Conference Date: Monday 22 January 2001
Conference Location: San Jose, CA, USA
Conference Title: Optical Diagnostics and Sensing of Biological Fluids and Glucose and Cholesterol Monitoring
Conference Chairs: Alexander V. Priezzhev, Gerard L. Cote
Inthe past two decades, the applications of optical monitoring fornon-invasive assessment of glucose have been pursued with limited success.We have investigated potential application of optical coherence tomography (OCT)for non- invasive and continuous monitoring of blood glucose concentration.An OCT system with the wavelength of 1300 nm wasused in phantom and in vivo studies. Polystyrene spheres withthe diameter of 0.76 micrometers were used as scatterers inaqueous solutions in the phantom studies. We have found 4.5%change of the OCT signal slope as a function ofglucose concentration in the range from 0 to 100 mMin the phantoms. This is in good agreement with theoreticalcalculations performed using Mie's theory. Bolus glucose injection and glucoseclamping experiments were performed in New Zealand rabbits and Yucatanmicropigs. OCT images were obtained from skin (dorsal area ofthe pigs and rabbit ear). Our pilot studies show closecorrelation between actual blood glucose concentration and slope of theOCT signals. The slope decreased substantially (about 40% in tissuesin vivo) with the increase of blood glucose concentration from4 to 30 mM. In conclusion, we have demonstrated thatglucose-induced changes in optical properties of skin can be monitoredby OCT suggesting that a new OCT-based optical sensor couldbe developed for sensitive and accurate non-invasive monitoring of glucoseconcentration in vivo.