Ophthalmic Artery-Resistive Index and Evidence of Overperfusion-Related Encephalopathy in Severe Preeclampsia

Neurological findings in preeclampsia fulfill diagnostic criteria of posterior reversible encephalopathy syndrome (PRES), which is related to cerebral autoregulation impairment associated with high blood pressure. In preeclampsia, PRES may occur without a significant increase in blood pressure. Our aim was to investigate the association between ophthalmic artery resistive index (OARI) and clinical evidence of PRES, defined as the presence of headache and blurred vision, in patients with severe preeclampsia. OARI and main clinical and laboratory parameters were obtained in 112 patients with severe preeclampsia. Differences in these parameters were analyzed in the function of clinical evidence of PRES with a 2-sample t test. The area under receiver operating characteristic curve for each of these parameters in the function of clinical evidence of PRES was obtained. Logistic regression models were established with parameters categorized by cutoff points obtained in receiver operating characteristic curves. Among 112 patients with severe preeclampsia, 46 (41%) presented clinical evidence of PRES. These patients presented lower OARI (P<0.0001), higher mean blood pressure at admission (P<0.0001), higher mean blood pressure elevation after the first trimester (P<0.0001), and higher lactate dehydrogenase (P<0.0001) than those without clinical evidence of PRES. OARI presented an area under receiver operating characteristic curve of 0.810 +/- 0.039 (95% CI: 0.742 to 0.895; P<0.0001). OARI <0.56 was associated with clinical evidence of PRES, with an odds ratio of 12.67 (95% CI: 4.08 to 39.39; P<0.0001). Data suggest that OARI is a relevant biomarker of PRES in severe preeclampsia. (Hypertension. 2010; 55: 189-193.)