Ophthalmic artery Doppler velocimetry in healthy pregnancy

OBJECTIVES: To establish normative data for ophthalmic artery Doppler parameters throughout a healthy pregnancy, to investigate the possible correlation between these Doppler measurements and gestational age, and to test intraobserver variability. METHODS: A prospective cross-sectional study was performed to assess various Doppler parameters in 276 healthy women between 20 and 39 weeks of gestation. The following measurements were obtained: pulsatility and resistance indices (PI, RI), peak systolic velocity (PSV), peak diastolic velocity (PDV), end diastolic flow velocity (EDFV), and peak ratio (PR). Quantile regression was used to estimate reference values throughout pregnancy and P<0.05 was considered significant. The intraclass correlation coefficient (Intra-CC) was used to calculate intraobserver variability. RESULTS: The 5th and 95th prediction intervals for each gestational age are presented. No significant correlation was detected between Doppler indices and gestational age. Intra-CC was excellent (0.996). CONCLUSIONS: Reference values were generated for ophthalmic artery Doppler measurements, and they did not vary significantly during healthy pregnancy.