Abstracts

Rationale: Hippocampal sclerosis (HS) is a common cause of medically refractory mesial temporal lobe epilepsy (MTLE, Quigg et al., 1997). Hippocampal injury is also implicated in the pathophysiology of major depression; unilateral and bilateral hippocampal atrophy have been reported in patients with major depressive disorder (Campbell et al., 2004; Videbech and Ravnkilde, 2004). As psychiatric conditions are prevalent in patients with epilepsy mainly mood and anxiety disorders (Ertekin et al., 2009; Guarnieri et al., 2009; Sperli et al., 2009; Tellez-Zenteno et al., 2007), we evaluated whether mood disorders were associated with hippocampal sclerosis in a cohort of patients with MTLE. Methods: This prospective cohort analysis included 13 patients who underwent neurosurgical intervention for intractable epilepsy at the South Texas Comprehensive Epilepsy Center (STCEC), between 2010 and 2012. The study was approved by the UTHSCSA IRB office. Demographic variables were evaluated such as age, gender, marital status, education level, and employment; while clinical variables included age at onset of epilepsy, etiology of epilepsy, presence of Axis I Disorders (assess using the Mini International Neuropsychiatric Interview MINI PLUS), age at surgery, area of resection, and MRI findings. Results: The majority of patients were male (54%), single (54%), with a high school degree (69%). Mean age at time of resection was 31 years. MRI lesions were found in twelve (92%) patients. Ten (8%) patients had temporal lobe epilepsy, seven of whom had right-sided foci. HS was identified in 7 (54%) of patients, while the remaining three had cortical dysplasia and encephalomalacia. Preoperative depression mood was diagnosed in 46%, followed by anxiety in 31%. All were on psychotropic medications either antidepressant or atypical antipsychotic. Depression was diagnosed preoperatively in 46% of patients with temporal lobe epilepsy and 31% of patients with HS. While all were seizure free and maintained on psychotropic medications at three and six months follow-up, none of the patients suffered an exacerbation of the mood symptoms after surgery. The same was found for three patients (23 %) with extratemporal foci, 67% of them had presurgical diagnosis of depression, and were taking psychotropic medications at time of surgery, none of them had postsurgical exacerbation of depressive symptoms at three and six months follow up and all of them were seizure free. Conclusions: This study presents preliminary data on psychiatric outcome in a prospective cohort undergoing epilepsy surgery. While the numbers are still small, this cohort confirms the association of HS with depression. With adequate psychotropic treatment there is no evidence of worsening of depression in patients with HS posoperatively, particularly when they are seizure free.