COLOR DOPPLER IMAGING - A NEW TECHNIQUE TO ASSESS ORBITAL BLOOD-FLOW IN PATIENTS WITH DIABETIC-RETINOPATHY

Purpose. Color Doppler imaging is a new noninvasive technique that ena bles measuring blood flow velocity in small orbital vessels, arteries as well as veins. Because hemodynamic changes are seen in patients wit h diabetic retinopathy by other techniques, the authors compared 61 ey es with proliferative, 59 eyes with nonproliferative, and 26 eyes with preproliferative diabetic fundus changes with a matched control group of 70 patients without diabetes (128 eyes). Methods. The central reti nal artery (CRA), short posterior ciliary artery (PCA), and ophthalmic artery (OA) of all patients were examined, and the systolic, diastoli c, and mean velocities were measured for each vessel. Results. Differe nces between the groups were most prominent in the CRA. The perfusion velocity was significantly lower (P < 0.001) in proliferative eyes (V- systolic 5.7 +/- 1.8 cm/sec) than in the control group (V-systolic 9.4 +/- 1.2 cm/sec) or in nonproliferative eyes (V-systolic 8.4 +/- 1.8 c m/sec). In the preproliferative group, there was great variability in velocity distribution. Consequently, no statistically significant diff erence could be deduced, either in the group with background retinopat hy or in the group with proliferative diabetes. In the OA and PCA, nei ther group showed significant differences from normal. Conclusions. Me asurements indicate a correlation between severity of diabetic retinop athy and decreased flow velocity in the CRA.