Do infants with isolated congenital sixth nerve palsy require comprehensive work-up? A retrospective cohort and review of the literature.

ABSTRACT

PURPOSE: The purpose of this study is to describe a case series of infants with isolated congenital sixth nerve palsy (ICSNP) and suggest a management algorithm based on our experience and a review of the literature. METHODS: A retrospective cohort design was used. The clinical database of a single tertiary medical center was reviewed to identify all patients diagnosed with ICSNP from January 2020 to November 2022. Data were collected as follows demographic parameters, age at initial presentation, presenting symptoms and signs, findings on ophthalmic and neurologic examinations, findings on follow-up, and outcome. RESULTS: Six patients were included. All were born at term. The average gestational weight was 3675.7 ± 262.7 g. Three mothers had gestational diabetes. Five deliveries necessitated labor induction either by oxytocin (n = 4) or by membrane stripping followed by oxytocin (n = 1). One had also gone a forceps assisted delivery. Symptoms were noticed in all newborns by their parents within the first week of life. Ophthalmological and neurological examinations were otherwise unremarkable apart of one patient with a head turn to the side of the involved eye. Four patients underwent brain imaging that were unremarkable. All abduction deficits resolved by 1 to 3 months of age. Follow up examinations were unremarkable (mean follow up 14.3 ± 5.0 months, range 4-23). CONCLUSIONS: This case series, together with previous reports, support ICSNP's benign nature. We suggest an initial basic work-up that solely includes ophthalmological and neurological examinations which will be elaborated in case of any additional pathologic findings or if ICSNP does not fully resolve by 3 months.