The Predictive Value of Laser Doppler Flowmetry Monitoring for Diagnostic of Diabetic Patients and Healthy Control

Compare the microcirculatory velocity distribution in the model diabetes patients, with smoker subjects and non-smokers clinically normal. the blood flow was assessed in 57 DM patients, 19 smoker and 48 clinically normal subjects using a new velocity-resolved quantitative laser Doppler flowmetry technique. The LDF estimates red blood cell (RBC) perfusion in (nm/ml.s), separated into two velocity regions, v 1 mm/s. This study aims to evaluate a method using 785nm diode laser based engineering approach to measure average velocity, CRBC, and perfusion. Distinguish according method between subjects and patients would able LDF noninvasively technique with absence of pain and exposure to biological sharp object especially DM patients. Result the optimum cut –off for perfusion is <3.75nm/ml.s is associated with a test sensitivity of 71.9% and specificity of 93.8%. It this cut off value the test is able to classify subjects into cases with DM and healthy non-smokers with 81.9% accuracy. Test in position in this cut-off value (<0.008 mm/s) or 8 µm/s will establish the diagnosis of DM with PPV 92% pretest probability of having DM is 50% at high accuracy. The same positive test result will establish a diagnosis of DM with 99% confidence in a clinical context when DM (or tissue ischemia) has a high pretest probability (10%) based on clinical judgment. At the other extreme of test, the cut –off value with highest sensitivity (100%) was < 10.91nm/s) will excluded a diagnostic of DM (or tissue ischemia) with 100% confidence (NPV=100%).