Basim Abdulelah Ali Al- Janahi (1)
Background: Photophobia is one of the most disabling symptoms of migraine, affecting more than 80% of patients. Although traditionally attributed to ocular hypersensitivity, evidence suggests a central neural mechanism involving the thalamus and visual cortex.
Objective: To evaluate the relative contribution of ocular versus central mechanisms to photophobia in migraine patients.
Methods: Case–control study, 60 migraine patients and 40 healthy controls, with ophthalmic examination, photophobia threshold testing, visual evoked potentials (VEP), and validated questionnaires.
Results: Migraine patients had significantly lower photophobia thresholds (2,800 ± 320 lux) than controls (4,600 ± 410 lux; p<0.001). VEP recordings revealed shorter P100 latencies and higher amplitudes in migraineurs (p<0.01). Ocular health parameters showed no significant differences.
Conclusion: Photophobia in migraine is predominantly mediated by central neural mechanisms. Management should target cortical hyperexcitability and thalamic sensitization.
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