Objective:

We describe a 38-year-old female with medically refractory intractable epilepsy status post right hemispherectomy, who presented with right sided headache and status migrainosus, which showed concurrent ictal activity on electroencephalogram (EEG).

Background:

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Design/Methods:

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Results:

We present a case of a 38-year-old female with a known diagnosis of medically refractory childhood onset focal epilepsy who  sustained multiple epilepsy surgeries, despite maximal medical therapy. She eventually underwent right hemispherectomy in 2013, following which her seizures were well controlled on levetiracetam 750 mg twice daily. In 2023, she presented to the emergency room with new onset right sided retro-orbital headache with nausea and photophobia, suggestive of migraine. Her headache did not respond to usual conservative measures such as NSAIDs, magnesium oxide, and a short course of corticosteroid therapy. Video EEG monitoring showed multiple recurrent electrographic seizures, nearly every 3-4 minutes, originating from right centrotemporal region, suggestive of focal status epilepticus without motor or sensory deficits. We hypothesized a correlation between ongoing subclinical electrographic seizures and her persistent headache. Low dose topiramate was initiated for a provisional diagnosis of ictal migraine, following which she reported significant symptomatic improvement on subsequent visits. Follow up EEG showed resolution of electrographic ictal activity, which substantiated the diagnosis of ictal migraine. She is currently asymptomatic on levetiracetam 750 mg twice daily and topiramate 100 mg BID.  

Conclusions:

Persistence of ictal activity following hemispherectomy is well documented, however they are largely subclinical owing to the disconnection achieved during surgery. In our patient, the subclinical epileptiform activity presented as migrainous headache. We propose that this unique semiology occurred due to the activation of the trigemino-vascular system by cortical spreading depression generated from persistent right sided ictal activity. Ictal migraine following hemispherectomy is rarely reported in literature, and it should be considered in patients with refractory headaches during the course of epilepsy treatment.