MR artifact mimicking a temporal lobe lesion in an epilepsy patient

A ten-year-old healthy child presented with a right upper extremity focal s eizure which secondarily generalized. Magnetic resonance imaging (MR) revea led a 1-cm area of abnormal signal intensity in the left posterior temporal robe at the gray-white junction. This did not appear on all imaging sequen ces, raising the suspicion of an artifact. Repeat MR revealed no intracrani al or extracranial pathology. This case illustrates MR 'wrap around' artifa ct that mimicked a temporal lobe abnormality in an epilepsy patient, The ph ysics of MR are reviewed as they pertain to this artifact.