Headache as an extraocular manifestation of birdshot chorioretinopathy: a case series.

Birdshot chorioretinopathy (BSCR) is a type of chronic posterior uveitis with limited characterization of extraocular manifestations, including headache. We describe two HLA-A29-positive patients with BSCR who developed refractory unilateral periorbital headaches temporally associated with visual symptom onset. Headaches lateralized to the more affected eye and the patients exhibited migrainous and prominent cranial autonomic features resembling trigeminal autonomic cephalalgias (TACs) and variable responses to standard headache therapies. Together, this supports the International Classification of Headache Disorders (ICHD-3) classification as a secondary headache attributed to ocular inflammatory disease. The biological plausibility of this association is supported by trigeminal innervation of the uveal tract, providing a substrate for inflammation-driven trigeminovascular activation. Systematic studies are needed to define BSCR-associated headache prevalence, phenotype, and mechanisms and to inform diagnosis and management.