Synophthalmia in an early human fetus

Background The great majority of reports dealing with human cyclopia and sy nophthalmia are derived from fetuses at the end of pregnancy. Thus, data co ncerning early organization of the ocular anlage in this impressive ocular developmental anomaly are almost completely lacking. We therefore present a 12 week-old synophthalmic fetus. Case report After uneventful pregnancy spontaneous abortion occurred. Withi n the face of the hypotrophic fetus there was a central pigmented ocular an lage with an inferior fissure. A nose (proboscis) was not discernible. Hist ologically, there were two vesicles caudally which fused to one vesicle cra nially. Differentiation was more advanced in the anterior and temporal part s of the anlagen. A coherent inner layer (of the optic cup) was not develop ed. Trisomy 13 was suspected but could not be proved by FISH-technique, Conclusions The fetus demonstrates that fusion of the ocular anlagen is fin ished at the end of the third gestational month and that synophthalmia/cycl opia is very likely to be associated with maldevelopment of the optic cup. As far as we know there is evidence for the first time that organization of the anlagen improves not only in the posterior to anterior and in the medi al to lateral but also in the cranial to cauda direction.