RESUMO
Objective To determine the affected factors of intraorbital hemodynamic results in diabetic retinopathy (DR) and the risk factors related to the occurrence of DR. Methods Posterior ciliary artery (PCA), central retinal artery (CRA), central retinal vein (CRV), and vortex vein (VV) of 68 patients with DR were measured by color Doppler flow image (CDFI). Thirty-one hemodynamic parameters, including systolic velocity, diastolic velocity, mean velocity, resistive index, pulsatility index and accelerative velocity of ophthalmic artery (OA), and other variates (blood pressure, blood sugar, gender, age, duration of the disease, and so on) were collected and clustered in a principal components analysis following a forward, stepwise logistic regression on these components. Results Nine principal components were extracted from 37 original variates, reflecting the velocity of OA, velocity of PCA, resistance of OA, velocity of CRA, resistance of CRA, resistance of PCA, time-related factor, venous drainage factor and gender factor, respectively. In the result of logistic regression, resistance of OA, velocity of CRA, resistance of PCA, time-related factor, and venous drainage factor were the risk factors related to DR. Conclusion The first risk factor affecting DR is time, and intraorbital hemodynamic abnormity influencing the development of diabetic retinopathy may be the increase of resistance of OA, decrease of velocity of CRA, decrease of resistance of PCA, and increase of venous drainage.