Ophthalmic artery blood flow velocity in healthy term and preterm neonates

Ophthalmic artery blood flow velocity (OA-BFV, cm/s), cerebral blood flow velocity (C-BFV, cm/s), and cardiac output (ml/min) were measured by pulsed Doppler sonography in 15 healthy term and 10 well preterm (26-35 wk) infants in the first week of life. OA-BFV did not increase with increasing gestational age (preterm: peak systolic BFV 29 +/- 5 cm/s, mean BFV 7.2 +/- 1.5 cm/s; term: peak systolic BFV 27 +/- 5 cm/s, mean BFV 6.6 +/- 1.3 cm/s), unlike C-BFV (preterm: peak systolic BFV 34 +/- 8 cm/s, mean BFV 9.4 +/- 2.3 cm/s; term: peak systolic BFV 43 +/- 9 cm/s, p less than 0.05; mean BFV 11 +/- 3.0 cm/s, p less than 0.05) and cardiac output (preterm 329 +/- 128 ml/min, term 732 +/- 112 ml/min; p less than 0.001). The ratio of OA-BFV/C-BFV was significantly higher in preterm than in term infants (p less than 0.01). In preterm infants, but not in term infants, there was a positive linear correlation of OA-BFV to C-BFV (r = 0.88). We conclude that it is possible to measure opthalmic artery blood flow velocity in neonates by pulsed Doppler sonography. Gestational age has different effects on OA-BFV and on C-BFV. Although it is a point of discussion if blood flow velocities are reflecting absolute blood flow, Doppler assessment of OA-BFV could be a tool for monitoring risk factors for retinopathy of prematurity.