Ophthalmic Artery Doppler Velocimetric Values in Pregnant Women at Risk for Preeclampsia

Abstract

Objectives-The purposes of this study were to describe ophthalmic artery Doppler parameters in pregnant women at risk for preeclampsia in the second trimester, compare them with reference values described in women with healthy pregnancies, and evaluate the association between gestational age and Doppler parameters. Methods-We conducted an observational study with prospective data collection in which measurements of 7 ophthalmic artery Doppler parameters were obtained in 274 women at 20 to 28 weeks' gestation with clinical risk factors for preeclampsia. The following measurements were obtained: peak systolic velocity, mesodiastolic velocity, mean velocity, end-diastolic velocity, resistive index, pulsatility index, and peak ratio. The observed Doppler values were compared with reference values by a 1-sample t test. To test for linear associations between gestational age and Doppler parameters, the Pearson correlation coefficient was used. Results-Significantly higher ophthalmic artery Doppler velocimetric parameters were observed when compared with the reference values. The mean values of these parameters ± SD were as follows: peak systolic velocity, 37.9 ± 10.3 cm/s (reference, 34.2 cm/s; P< .001); end-diastolic velocity, 7.2 ± 3.1 cm/s (reference, 6.8 cm/s; P= .03); resistive index, 0.81 ± 0.07 (reference, 0.70; P < .001); pulsatility index, 2.17 ± 0.53 (reference, 1.80; P < .001); and peak ratio, 0.53 ± 0.12 (reference, 0.40; P < .001). There was no correlation between the Doppler parameters and gestational age. Conclusions-Ophthalmic Doppler parameters of women at risk for preeclampsia are significantly higher than reference values for healthy pregnancies, which may indicate an inadequate vascular response to persistent peripheral resistance. Gestational age during the second trimester is not associated with ophthalmic artery Doppler parameters in pregnant women at risk for preeclampsia. © 2012 by the American Institute of Ultrasound in Medicine.