B-SCAN OCULAR ULTRASONOGRAPHY IN PRETERM AND TERM INFANTS

Purpose: To evaluate the normal B-scan ocular ultrasonographic finding s in preterm and term newborns. This information would be useful in ma king perinatal ocular diagnoses, especially in consideration of the ra pidly changing eyes of normal infants shortly after birth. Methods: On e hundred two healthy infants aged 28 to 48 weeks postconception were prospectively studied. Eighty-six had complete sonograms, while others had incomplete examinations due to systemic instability. B-scan ultra sonography was conducted through acoustic coupling medium and a closed eyelid using the Coopervision Ultrascan 404 unit. The ultrasound find ings were evaluated relative to the infant's postconceptional age and weight at examination and the axial lengths of each eye. The ultrasono grapher, who determined the presence of abnormal findings, was masked to the parameters mentioned above. Results: Four specific findings fre quently were noted in newborns that would be considered abnormal in ad ult eyes. These were: 1) a visible Tenon's capsule; 2) prominent super ior ophthalmic vein; 3) sonolucent extraocular muscles; and 4) vitreou s opacities. These findings were more common in the more premature inf ants (P<0.01: by t test). Conclusions: The presence of these four ultr asonographic findings in the eyes of infants should be considered norm al, and should not necessarily prompt further work up until after the perinatal period.