The rare phenomenon of Marcus-Gunn jaw winking without ptosis: Report of 14 cases and review of the literature

Purpose: To report a rare case series of 14 patients of the Marcus-Gunn jaw-winking phenomenon (MGJWP) without ptosis. Methods: This was a retrospective noninterventional case series. The medical records of all patients diagnosed with MGJWP over the past 10 years were retrieved. Patients with documented evidence of absence of ptosis were segregated and analyzed for visual acuity, the severity of Marcus-Gunn, the presence of squint and amblyopia, and the presence of other aberrant regenerations. Results: A total of 207 patients were diagnosed with MGJWP, out of which 14 (6.76%) patients had isolated MGJWP without blepharoptosis. The mean age of presentation was 9.5 years and males and females were equally affected. The left eye was involved more commonly (57.2%) than the right eye. Twelve patients were congenital and two were presumed to be of traumatic origin. The most common refractive error in this cohort was astigmatism (10, 71.42%), followed by hyperopia (5, 35.71%). One patient had anisometropic amblyopia. Marcus-Gunn was found to be mild (≤2 mm of lid excursion) in all cases. None of the patients had strabismus or any other aberrant innervations. None of the patients underwent surgery and did not develop ptosis or worsening or improvement of Marcus-Gunn after a mean follow-up period of 2.3 years. Conclusion: Isolated MGJWP in the absence of ptosis is a very rare entity and this is the largest series to date to report such an occurrence. All patients had a mild form of MGJWP with no intervention required in any of the cases.