THE ASYMMETRIC MAMILLARY BODY - ASSOCIATION WITH MEDIAL TEMPORAL-LOBEDISEASE DEMONSTRATED WITH MR

PURPOSE: To determine whether mamillary body atrophy is caused by deaf ferentation of the mamillary body in patients with mesial temporal scl erosis. METHODS: We studied 36 patients with thin-section MR to assess mamillary body symmetry. These patients included 10 control subjects without seizures and 26 patients with a history of seizures. Thin-sect ion T1 scans were available for all cases, The patients with epilepsy underwent axial and coronal T2 scans as well. RESULTS: In five of eigh t cases with prior medial temporal lobe resection for intractable epil epsy, there was evidence of unilateral mamillary body atrophy ipsilate ral to the resection. Similar findings were evident in three of six pa tients with MR findings of mesial temporal sclerosis without surgery. Two patients with medial temporal stroke or tumor also had ipsilateral mamillary body atrophy. CONCLUSION: These findings provide support fo r the proposed mechanism of mamillary body atrophy caused by prior med ial temporal lobe injury.