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Focal epilepsy — MSRA MCQ

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HardMRIFocal epilepsyMSRA

A 34-year-old man is reviewed in a first-seizure clinic. Over 5 months, he has had two unprovoked stereotyped episodes. Each began with a rising epigastric sensation followed by behavioural arrest, lip-smacking and unresponsiveness for approximately 90 seconds. After the second episode, witnesses observed evolution to bilateral tonic-clonic movements. He has no fever, recent head injury, alcohol withdrawal, recreational drug use or metabolic disturbance. Twelve-lead ECG, glucose, electrolytes and neurological examination are normal. Routine EEG shows left temporal epileptiform discharges. The epilepsy specialist diagnoses focal epilepsy. He has no MRI contraindication and is clinically well at review. What is the most appropriate initial neuroimaging plan?

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Correct answer: A — Arrange an MRI brain using the locally agreed epilepsy protocol within 6 weeks of referral

Explanation lettering: C = shown as A · E = shown as C · A = shown as E

This patient has diagnosed focal epilepsy: his recurrent stereotyped focal impaired-awareness seizures, temporal epileptiform EEG changes and focal-to-bilateral tonic-clonic evolution are concordant. NICE recommends MRI for adults diagnosed with epilepsy unless they have idiopathic generalised epilepsy or a self-limited childhood epilepsy syndrome. MRI should use a regionally agreed epilepsy protocol and be performed within 6 weeks of referral. It is the preferred investigation for detecting a relevant structural cause and informing management. A is inappropriate because he is clinically stable, has no acute neurological deficit, trauma, persistent altered consciousness or other feature requiring emergency CT. B is inferior because CT is an alternative when MRI is contraindicated, not the routine first-line structural investigation in an MRI-eligible adult with epilepsy. D confuses repeat or tertiary review imaging in ongoing diagnostically difficult or treatment-resistant epilepsy with the recommended initial imaging after diagnosis. E incorrectly applies the imaging exception for idiopathic generalised epilepsy; focal semiology and focal EEG findings instead strengthen the indication for MRI.

Reference: NICE NG217: Epilepsies in children, young people and adults — Diagnosis and assessment of epilepsy, section 1.3 Neuroimaging (Published 27 April 2022; last updated 30 January 2025) — https://www.nice.org.uk/guidance/ng217/chapter/diagnosis-and-assessment-of-epilepsy