Headache in optic neuritis: A retrospective case-control study revealing clinical and radiological associations of an underrecognized symptom

Background: Headache is a common but underrecognized symptom in optic neuritis (ON), with potential implications for diagnosis and management. Objective: To assess the clinical and radiological factors associated with headache in patients with acute ON. Methods: We conducted a retrospective case-control study in a tertiary hospital in Bogotá, Colombia (2022–2024). Adults diagnosed with ON based on clinical evaluation and magnetic resonance imaging (MRI) were included and classified according to the presence or absence of headache. Diagnosis was established based on the 2022 criteria proposed by Petzold et al. (1). MRI was reviewed by a neuroradiologist. Headache phenotypes were defined using ICHD-3 criteria. Logistic regression was used to identify independent predictors. Results: Among 171 patients, 69 (40.4%) reported headache. Headache was associated with a personal history of primary headache (OR 7.14; 95% CI: 3.0–15.8; p = 0.009) and optic nerve lesions >12 mm (OR 2.34; 95% CI: 1.17–4.70; p = 0.016). Migraine without aura was the predominant phenotype (62.3%). Headache onset was simultaneous with vision loss in 58.0% of cases. No significant differences were found in antibody profiles or final diagnoses. Conclusions: Headache in ON is frequent, clinically relevant, and associated with radiological markers of inflammation. Systematic assessment of headache in ON may help identify patients with greater inflammatory burden, potentially guiding early diagnosis and individualized management.