[Features of retinal blood flow in pregnant women with carbohydrate metabolism disorders]

Studying the condition of retinal blood flow in pregnant women with disorders of carbohydrate metabolism contributes to early detection of diabetic retinopathy (DR), which is necessary for timely treatment and preservation of high visual functions.

To study retinal blood flow in pregnant women with disorders of carbohydrate metabolism using optical coherence tomography angiography (OCTA) in order to determine the criteria for manifestation and progression of DR.

The study examined 203 pregnant women in the third trimester: 24 - with type 1 and 2 diabetes (T1D and T2D), 143 - with gestational diabetes (GD), and 36 apparently healthy women with physiological pregnancy that comprised the control group. OCTA imaging was performed on RTVue XR Avanti ("Optovue", USA) system using HD Angio Retina 6.0 mm² scan protocol. The whole image vessel density (wiVD), foveal vessel density (FVD), and foveal avascular zone (FAZ) area in the superficial capillary plexus were studied.

FVD was significantly lower in pregnant women with diabetes than in pregnant women with GD and in the control group, prompting an assumption that retinal microvascular regulation changes because of chronic disturbances of carbohydrate metabolism in such patients and due to development of microangiopathy. Statistically significant increase in FAZ area and decrease in wiVD were revealed in patients with DR compared to data from the group of pregnant women with diabetes but without DR, in the absence of differences in FVD. In 2 patients with T1D and no ophthalmoscopic signs of DR, OCTA revealed areas of nonperfusion in the posterior pole of the eye.

OCTA can help identify areas of retinal nonperfusion in the posterior pole of the eye in pregnant women with diabetes and no ophthalmoscopic signs of DR, and determine objective indications for timely retinal laser coagulation.