The goal of this project is to develop a small handheld device that can be used for both near continuous and discrete noninvasive measurement of blood glucose from the finger. VivaScan has developed and successfully tested several noninvasive blood glucose monitor laboratory prototypes that use the earlobe as the measurement site. Their operations are based on measurements of near-infrared (NIR) light attenuation by glucose using the patented Optical BridgeTM (OB) method. The OB uniquely nulls out the background attenuation of the tissue, overcoming the major problem of optical blood glucose measurements. In the Phase I study, VivaScan developed a prototype portable device that noninvasively measures blood glucose from the finger. Its tests produced 98.2% of the data (877 data pairs) in the clinically acceptable A & B zones in the Clarke error grid, with an average measurement error of 18.5% or 20.5 mg/dl. Based on the Phase I study, we concluded that the finger is a better noninvasive measurement site than the earlobe because: 1) it is a more ergonomic measurement site; 2) finger measurements do not require active participation of the user allowing also for automated near continuous measurements on sleeping or unconscious patients (e.g. in hospital environment); and 3) finger measurements are easier to perform. In addition, numerous opportunities for improvement have been identified. Overall, the goal of the proposed work is to extend our laboratory prototype portable system to a patient oriented affordable small handheld device. The main aims for Phase II include: 1) develop a custom laser diode system light source; 2) enhance the electronics; 3) redesign and miniaturize the optics and device mechanics; 4) design a handheld system; 5) further enhance the glucose measurement algorithms; 6) achieve one point calibration; 7) build three handheld devices; and 8) test their performance with patients. Our performance goals include: 1) achieve a blood glucose estimation accuracy nearing existing individual finger prick invasive blood glucose measurement devices (=?15%); 2) achieve both near continuous and discrete measurements; and 3) achieve instrument stability requiring one point calibration (with a finger prick device) less than once a week. Subsequent FDA approval of a handheld personal blood glucose monitor will be sought. More than 18 million people in the United States are afflicted with diabetes. Poor management of the disease, (often due to the patient's reluctance to stab themselves for the necessary blood sugar reading), results in debilitating complications ranging from blindness to renal failure. Several national studies have concluded that these complications could be prevented by more frequent testing of blood sugar, which would be facilitated by a painless, bloodless glucose monitor such as the one we propose to develop here. ? ? ?
| Medina-Contreras, Oscar; Geem, Duke; Laur, Oskar et al. (2011) CX3CR1 regulates intestinal macrophage homeostasis, bacterial translocation, and colitogenic Th17 responses in mice. J Clin Invest 121:4787-95 |
