THE DEVELOPMENT OF THE FETAL EYE - IN-UTERO ULTRASONOGRAPHIC MEASUREMENTS OF THE VITREOUS AND LENS

Our objective was to establish nomograms for fetal eye measurements fr om 12 weeks' gestation by using transvaginal and transabdominal high-r esolution ultrasound techniques. A prospective cross-sectional study w as performed on 450 normal singleton pregnancies between 12 and 37 wee ks' gestation. Vitreous and lens circumferences were measured by trans vaginal ultrasonography until 17 weeks, and by abdominal ultrasound be tween 18 and 37 weeks' gestation. Regression analyses were used to cre ate nomograms, and several transformations were done to obtain lineari ty. Eye measurements of 12 fetuses at risk for ocular disturbances wer e plotted on the constructed nomograms. Linear relationships were fitt ed between vitreous (r(2)=0.79) and lens (r(2)=0.88) circumferences an d gestational age. In addition, there was a significant correlation be tween these measurements and the biparietal diameter. Data of the fetu ses at risk showed that disturbances in ocular growth were associated mainly with abnormal cerebral development. These normative data may be helpful in the prenatal diagnosis of suspected congenital syndromes t hat include, among their manifestations, ocular growth disturbances su ch as microphthalmos and anophthalmos.