The amygdala and anxiety after epilepsy surgery.

The relationship between amygdalar volume and anxiety after epilepsy surgery was explored. Participants comprised patients who underwent mesial temporal (n=26) or non-mesial temporal resections (n=16) and 41 neurologically normal controls. Anxiety was prospectively measured preoperatively and for the first 12 months postoperatively using criteria from the Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition. Amygdalar volumetry was performed on preoperative and control T1-weighted MRI scans. Resection of an ipsilateral amygdala of normal volume, relative to controls, was associated with postoperative anxiety in patients with mesial temporal resections, regardless of seizure outcome [F(1, 22)=5.17, P<0.05]. There was no relationship between amygdalar volume and anxiety in patients with non-mesial temporal resections, or between contralateral amygdalar volume and anxiety in patients with mesial temporal resections (P>0.05 for all comparisons). In conclusion, resection or deafferentation of an amygdala with a volume within the normal range was associated with increased postoperative anxiety.