Abstract
Purpose:
Classically, “congenital esotropia” designated “early-onset esotropia”. The latter replaced the former as esotropia is virtually never seen at birth but appears over the first months of life. In rare instances, however, true constant esotropia is said to be seen at birth. Only then, when seen in the very first days of life, could it be called true congenital esotropia (CE). Here we tested the hypothesis that CE does exist and that it is a radically distinct entity from early-onset esotropia.
Methods:
Retrospective study of all cases of neonates referred to the pediatric neuro-ophthalmology clinic between October 2010 and 2014 for a constant esotropia seen at birth and formally assessed. In addition to follow-up appointments and systematic complete general pediatric examination, two systematic ophthalmologic examinations were achieved: the first one within the three first weeks of life looked for prenatal and perinatal history, an ophthalmologic malformation, and any associated pathology; it assessed the diagnosis and the nature of esotropia; the last one at 8 months included an ophthalmologic and an orthoptist examination assessing visual function, binocular vision (Lang test) and esotropia evolution.
Results:
Ten patients were included. Among them, 70% of patients had a franc abduction limitation of the right eye and 30% of the left eye. Esotropia regressed completely in 9/10 cases. The median time of disappearance was 4 weeks (3 - 9 weeks). The patient who did not have a complete regression was subsequently diagnosed as Duane retraction syndrome (DRS). There was no consanguinity, no prematurity among these patients; four had had a difficult delivery: two needed instrumental delivery (forceps), one was a breech delivery, and one had a wrapped umbilical cord. One patient had a prenatal history of toxoplasmosis seroconversion at three months that had resulted in a treatment (Spiramycin). No patient had any sign of amblyopia and all had a positive Lang test.
Conclusions:
True CE does exist and can be defined as a constant esotropia in a healthy newborn with a complete spontaneous regression in 100% of cases. The clinical characteristics and evolution of true CE are the ones of a congenital abducens nerve palsy, which would regress early enough to allow for a realignment of the visual axes during the critical period for visual development. It would therefore result in orthophoria with normal retinal correspondence, as opposed to early-onset esotropia.