Abstract
Purpose :
To describe a case of an infant with unilateral proptosis and bilateral asymmetric extraocular muscle (EOM) aplasia / hypoplasia in the setting of bilateral posterior embryotoxon.
Methods :
Observational case report
Results :
A full-term newborn was consulted for evaluation of a wide nasal bridge and anisocoria. Birth history was significant for anti-phospholipid antibody syndrome in the mother. Family history revealed hypertelorism in the brother with limited negative work-up, bilateral congenital cataracts in the mother, and congenital cardiac abnormalities in the brother and mother. Newborn screen was normal and the newborn evaluation was notable for a large atrial septal defect. Ophthalmology exam showed blink to light vision OU, anisocoria symmetric in light and dark without an APD, abduction deficits OS > OD, adduction deficit OS, corneal haze OU, posterior embryotoxon OU, and normal remainder of exam. She was noted to have left eye buphthalmos versus proptosis and underwent exam under anesthesia (EUA) with MRI head / neck at 5 months. EUA revealed IOP 21 OD and 24 OS, corneal haze OU, megalocornea OU, gonioscopy with peripheral anterior synechiae to posterior embryotoxon OU, pachymetry 670s OU, and axial lengths of 20.24 OD and 20.73 OS. Fundus exam OU showed normal nerves with 0.1 cup to disc ratio, blunted foveal light reflex and was otherwise normal. MRI revealed right lateral rectus and left medial rectus hypoplasia and left lateral rectus aplasia and was otherwise unremarkable. Given the constellation of findings, genetic testing was recommended but deferred by parents other than testing for mucopolysaccaridoses, which was negative.
Conclusions :
In this patient, left eye proptosis was mistaken for congenital glaucoma-related buphthalmos from an anterior segment dysgenesis syndrome. Proptosis in this case is likely related to poor ocular tethering from EOM hypoplasia / aplasia. The latter could be related to a primary neurocristopathy resulting in anterior segment dysgenesis and associated EOM abnormalities as previous studies have suggested that neural crest migration is required for EOM development. Alternatively and less likely, this may be a case of a congenital cranial disinnervation disorder with incidental posterior embryotoxon. While genetic testing would be useful, the parents have elected to defer further work-up at this time.
This abstract was presented at the 2022 ARVO Annual Meeting, held in Denver, CO, May 1-4, 2022, and virtually.