Movement Disorders USMLE Step 1 Practice Question
A 62-year-old woman with hypertension and hyperlipidemia presents to the emergency department with abrupt-onset rhythmic jerking of the right hand that began 6 hours ago. Over the past 2 hours, the movements have spread to involve the right face and right leg in a sequential manner consistent with cortical representation. Vital signs are significant for BP 158/94 mmHg. On examination, the jerking movements occur at approximately 1-2 Hz, persist during sleep, and are unaffected by voluntary action or sensory stimulation. The patient denies loss of consciousness, tongue biting, or bowel/bladder incontinence. MRI brain with DWI/PWI shows a subacute infarct in the left precentral gyrus. CSF analysis is normal. Electroencephalography shows no epileptiform discharges corresponding to the movements. Which of the following best explains the patient's clinical presentation?
Answer choices
- AFocal seizures with secondary generalization from acute stroke
- BEssential tremor with acute exacerbation from hypertensive crisis
- CCortical myoclonus from acute ischemic strokeCorrect answer
- DSpinal cord myoclonus from coexisting cervical myelitis
- EPalatal tremor from pontine involvement on MRI
- FAsterixis from acute hepatic encephalopathy
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