Contact lens-associated ocular allodynia in migraine: A case report highlighting peripheral sensory input in central sensitization

Abstract

Allodynia, defined as the perception of pain from stimuli that are normally non-painful, is a hallmark of central sensitization in migraine pathophysiology. While cutaneous allodynia is well-documented, the clinical significance of ocular allodynia, particularly in association with contact lens wear, remains underreported. Here, the case of a 42-year-old female with a long-standing history of episodic migraine, characterized by unilateral throbbing pain (VAS 7-8/10), nausea, and photo-phonophobia, typically triggered by sleep deprivation and menstruation was presented. The patient, a long-term user of soft contact lenses for -3.0 diopter myopia, reported a unique temporal pattern of allodynia emerging over the last two years. She described a localized hypersensitivity on the symptomatic side, occurring in the prodromal phase several hours before the headache onset. This sensation rendered contact lens wear intolerable during the attack, independent of photophobia. Ophthalmological evaluations, including intraocular pressure and fundus examinations, were unremarkable. Despite a history of chronic migraine managed with amitriptyline and onabotulinumtoxinA, her current episodic attacks reveal a distinct ocular-tactile sensitivity. To our knowledge, this is the first reported case of contact lens-related ocular allodynia in migraine. This case emphasizes the necessity of screening for ocular allodynia in contact lens users, suggesting that lens intolerance may serve as a clinical marker for evolving central sensitization in migraineurs. Further research is warranted to elucidate the trigeminovascular mechanisms underlying this specific allodynic manifestation.