Multifocal analysis of the bioelectric potential and light sensitivity of the retina in thrombotic microangiopathy associated with malignant arterial hypertension

Abstract

This study evaluates the function of the retina according to multifocal electroretinography (mfERG) and its light sensitivity according to microperimetry (MP) in patients with thrombotic microangiopathy (TMA) associated with malignant hypertension (MH). The study analyzed mfERG and MP data of 20 patients (40 eyes) aged 40.4±7.4 years (18 men, 2 women) with MH-associated TMA. In all patients TMA of the kidneys was verified by nephrobiopsy. The control group consisted of 20 healthy individuals (40 eyes) of the appropriate age. A statistically significant decrease in the response density of P1 mfERG (nV/deg2) of the central retinal zone (0-27.7°) was found in study patients in comparison with the control group (p<0.05), differences in the latency of P1 mfERG (ms) were statistically insignificant (p>0.05). Analysis of MP data in study patients revealed a statistically significant decrease in the mean light sensitivity (dB) of the central field of vision (30°) (p<0.05) compared to the control group. A statistically significant correlation was found between the response density of P1 mfERG (nV/deg2) and mean light sensitivity (dB) in the corresponding quadrants of the visual field (p<0.05). A number of statistically significant correlations were found between the indicators of MP and mfERG and some non-ocular clinical manifestations of TMA in MH. A statistically significant decrease in the light sensitivity of the central field of vision caused by marked decrease in retinal function, probably of an ischemic nature, is characteristic for MH-associated TMA. In this disease the response density of P1 mfERG (nV/deg2) is a sensitive indicator of impaired retinal function. With the activation of systemic TMA, increase in blood pressure and deterioration of kidney function in MH, the light sensitivity of the eye also decreases.