Acute Onset Focal Epilepsy Mimicking Stroke

Area of Science:

• Neurology
• Neuroradiology

Background:

• Acute neurological disorders often present with stroke-like symptoms, termed 'stroke mimics'.
• Migraine aura and seizures are common stroke mimics, sometimes leading to misdiagnosis and inappropriate treatment with thrombolytics.
• Distinguishing stroke mimics from actual strokes is crucial for effective patient management.

Observation:

• A 70-year-old man presented with acute delirium and left arm weakness, initially suspected as stroke.
• Despite eligibility and treatment for stroke with IV alteplase, his symptoms improved but later seizure activity was suspected.
• Transient DWI-positive cortical lesions on MRI, resolving later, were observed, prompting a shift in diagnosis.

Findings:

• The patient was diagnosed with focal motor-onset seizures with impaired awareness, successfully treated with anti-seizure medications (ASMs).
• Serial MRI revealed characteristic but transient DWI lesions that normalized on follow-up, aiding in the diagnosis of seizures.
• The case demonstrates the potential for MRI to identify seizure-related alterations, even in the absence of ADC map abnormalities.

Implications:

• This case underscores the importance of considering seizures in stroke mimic presentations.
• Prospective MRI studies are needed to correlate electroclinical features with specific MRI patterns in stroke mimics.
• MRI may play a vital role in the differential diagnosis between seizures and stroke, optimizing treatment strategies.