Fetal Ocular Distance in Normal Pregnancies
Kanchapan Sukonpan MD*, Vorapong Phupong MD*
Affiliation : * Department of Obstetrics and Gynecology, Faculty of Medicine, Chulalongkorn University, Bangkok
Objective : To construct reference ranges of fetal ocular distance (interocular and binocular distance) and to
evaluate the relationships between the gestational ages and fetal ocular distance.
Material and Method: Six hundred and two normal pregnant women were evaluated from the 15th to 40th week
of gestation. Fetal ocular distance (interocular and binocular distances) was added to routine biometric
measurements for normal fetuses. The fetal ocular distance (interocular and binocular distances) was also
related to gestational age.
Results : Five hundred and ninety five measurements were used for analyses. A linear regression and correlation
were observed between gestational age (GA) and interocular distance (y = 2.304 + 0.510 x GA, R2 = 0.887;
p < 0.0001), and binocular distance (y = 2.590 + 1.420 x GA, R2 = 0.953; p < 0.0001). A linear growth
function was observed between biparietal diameter (BPD) and both interocular distance (y = 2.854 + 0.203
x BPD, R2 = 0.888; p < 0.0001), and binocular distance (y = 3.893 + 0.568 x BPD, R2 = 0.965; p < 0.0001).
Conclusion : The present study provides normative data of fetal interocular distance and binocular distance.
These data may be helpful in detection of fetal hypotelorism or hypertelorism.
Keywords : Fetus, Gestation age, Interocular, Binocular, distance, Ultrasound
