SELECTIVE AMYGDALOHIPPOCAMPECTOMY FOR HIPPOCAMPAL SCLEROSIS - POSTOPERATIVE MR APPEARANCE

PURPOSE: To analyze the anatomic consequences of selective amygdalohip pocampectomy (AH) in patients with hippocampal sclerosis and to correl ate the clinical outcome with the MR appearance. METHODS: Seventeen pa tients were examined with clinical and neuropsychologic examination an d cranial MR after AH (7 transcortical AH, 10 trans-Sylvian AH), The c linical and neuropsychologic outcomes after AH were compared with thos e of anterior lobectomy (ATL). RESULTS: There was no significant diffe rence in seizure cure between transcortical or trans-Sylvian AH and AT L, However, patients with left AH fared significantly better in terms of verbal IQ and nonverbal memory when compared with those with left A TL. Verbal memory and cognition were not significantly different in th e two AH groups. Variable amounts of hippocampal and amygdala remnants were found in both AH groups and did not correlate with seizure cure. White matter change consistent with gliosis probably secondary to wal lerian degeneration was demonstrated in the anterior temporal lobe to a mean distance of 4.5 cm after transcortical AH and to a lesser degre e as a consequence of trans-Sylvian AH. Nine patients (53%) (4 transco rtical AH, 5 trans-Sylvian AH) demonstrated wallerian degeneration in the optic radiations after surgery. All had incomplete contralateral q uadrantanopia. CONCLUSIONS: There is more secondary damage to the temp oral lobe after AH than was previously recognized. The extent of hippo campal and amygdala resection in AH do not seem to be directly related to seizure cure. Visual field defects are common in AH because of the anterior but variable course of the optic radiations.