Purpose: To determine ocular blood flow parameters by Doppler ultrasound scanning in type 2 diabetic patients with different stages of diabetic retinopathy. Material and Methods: In this prospective study, forty-five patients (90 eyes) with type 2 diabetes mellitus were divided into three groups of 15 patients each: no diabetic retinopathy group (DR0), non-proliferative retinopathy (NPDR), and proliferative retinopathy (PDR) groups. Doppler indices such as systolic blood flow velocity (Vs), diastolic blood flow velocity (Vd), time-averaged maximum velocity (TAMXV), pulsatility index (PI) and resistivity index (RI) in the ophthalmic artery (OA), central retinal artery (CRA) and short posterior ciliary arteries (SPCA) were determined. ANOVA was used for quantitative comparisons between the three groups. Results: There was a significant (р less 0.05) decrease in (a) the Vs from 71.1 +- 20.6 cm/s in the DR0 group to 59.9 +- 16.7 cm/s in the NPDR group and 47.4 +- 16.4 cm/s in the PDR group, (b) Vd from 22.1 +- 6.9 cm/s to 17.0 +- 6.6 cm/s and 12.3 +- 5.9 cm/s, respectively; and (c) TAMXV from 37.2 +- 11.3 cm/s to 31.9 +- 9.1 cm/s and 25.3 +- 9.7 cm/s, respectively, and an increase in the RI from 0.69 +- 0.06 cm/s to 0.71 +- 0.09 cm/s and 0.75 +- 0.08 cm/s, respectively, in the OA. In addition, there was a significant decrease in the Vd from 9.9 +- 5.4 cm/s in the DR0 group to 8.1 +- 3.8 cm/s in the NPDR group and 5.5 +- 3.1 cm/s in the PDR group, and an increase in the PI from 1.34 +- 0.16 cm/s to 1.46 +- 0.28 cm/s and 1.54 +- 0.24 cm/s, respectively, and in the RI from 0.71 +- 0.06 cm/s to 0.75 +- 0.07 cm/s and 0.80 +- 0.05 cm/s, respectively, in the CRA. Moreover, there was a significant decrease in the Vd from 4.3 +- 1.6 cm/s in the DR0 group to 3.2 +- 2.0 cm/s in the NPDR group and 3.1 +- 2.2 cm/s in the PDR group, and an increase in the PI from 1.32 +- 0.21 cm/s to 1.37 +- 0.24 cm/s and 1.54 +- 0.26 cm/s, respectively, and in the RI from 0.76 +- 0.04 cm/s to 0.82 +- 0.06 cm/s and 0.82 +- 0.06 cm/s, respectively, in the SPCA. Conclusion: We found that the arteries examined in patients with diabetic retinopathy tended to have decreased blood flow velocities and increased resistivity and pulsatility indices, with the greatest changes observed in patients with PDR. In addition, the difference in mean values of most Doppler indices between the PDR and NPDR groups was larger than that between the NPDR and DR0 groups.

To establish a relationship of diabetic retinopathy with the presence of lesions of other target organs, disease severity and the requirement for insulin therapy in patients with type 2 diabetes mellitus, and to determine the most significant prognostic markers. Material and Methods:We examined 270 patients (270 eyes) with type 2 diabetes mellitus. They were divided into the diabetic retinopathy group and no-diabetic retinopathy group. The status of diabetic target organs was determined as per endocrinologist's, cardiologist's, nephrologist's, neurologist's and vascular surgeon's conclusions. Statistica v6.1 (Statsoft, Tulsa, OK) software was used for statistical analysis. The level of significance р < 0.05 was assumed. Results: Diabetic retinopathy positively correlated with severe diabetes (r = 0.383, p < 0.001), insulin therapy requirement (r = 0.389, p < 0.001), diabetic nephropathy (r = 0.350, p < 0.001), chronic kidney failure (r = 0.390, p < 0.001), and lower-extremity angiopathy (r = 0.312, p < 0.001). In addition, the risk of diabetic retinopathy was high in patients on insulin therapy (odds ratio (