Familial dysautonomia is easily recognized by its unique combination of ocular findings. These include corneal hypesthesia, hypolacrima, exodeviations, methacholine-induced miosis, myopia, anisometropia, and tortuosity of retinal vasculature. Anisocoria and ptosis are also observed in this syndrome. Diagnostic confirmation can be obtained by noting the absence of fungiform papillae on the tongue and by observing an abnormal reaction to histamine injected into the skin. Evidence suggests that denervation supersensitivity exists in dysautonomic ocular structures, both to sympathetic and to parasympathetic stimuli. Prevention of corneal ulceration and perforation in affected patients requires early diagnosis and therapy, including the use of artificial tears, punctum occlusion, tarsorrhaphy, and occasionally corneal or conjunctival surgery.
Goldberg MF, Payne JW, Brunt PW. Ophthalmologic Studies of Familial DysautonomiaThe Riley-Day Syndrome. Arch Ophthalmol. 1968;80(6):732-743. doi:10.1001/archopht.1968.00980050734011