Fetal ocular distance in normal pregnancies.
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.


METHODS
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).


CONCLUSIONS
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.
Department of Obstetrics and Gynecology, Faculty of Medicine, Chulalongkorn University, Rama IV Rd, Pathumwan, Bangkok 10330, Thailand.
Kanchapan
K
Sukonpan
Vorapong
V
Phupong
D000328:Adult; D001699:Biometry / Q000295:instrumentation; D005128:Eye Diseases / Q000175:diagnosis; D005260:Female; D005333:Fetus / Q000033:anatomy & histology*; D005865:Gestational Age; D006801:Humans; D016014:Linear Models; D011247:Pregnancy; D011446:Prospective Studies; D012016:Reference Values; D012307:Risk Factors; D016216:Ultrasonography, Prenatal; D015348:Vision, Binocular / Q000502:physiology*