COLLATERAL SULCUS VOLUME CHANGES IN TEMPORAL LOBE EPILEPSY
Abstract number :
1.185
Submission category :
5. Human Imaging
Year :
2009
Submission ID :
9568
Source :
www.aesnet.org
Presentation date :
12/4/2009 12:00:00 AM
Published date :
Aug 26, 2009, 08:12 AM
Rationale: Hippocampal sclerosis is the most common underlying pathology in drug resistant temporal lobe epilepsy. Studies using MRI have shown that surrounding areas of the medial temporal lobe may also show changes in addition to or separate from hippocampal sclerosis. A study by Bernasconi et al. (Brain, 2006; 128: 2442-2452) found changes in the depth and angle of the collateral sulcus in patients with temporal lobe epilepsy who had malformations of cortical development. These findings are important in determining if other areas outside of the hippocampus may be involved in the pathology of temporal lobe epilepsy. It is unclear however, if these changes in the collateral sulcus effect the volume of gray matter in this region. Methods: To examine this question, five individuals with unilateral left temporal lobe epilepsy, as determined by long term video-EEG monitoring, were included in this study as well as 5 aged matched control subjects. Those with left temporal lobe epilepsy were selected based on the properties of the ipsilateral collateral sulcus (i.e. deeper and more vertical than controls). T1 weighted 3-D SPGR pulse sequence MRI images were acquired in all participants. Hippocampal volumes and the volume of the gray matter in the left collateral sulcus were derived by manually tracing consecutive T1 coronal slices reformatted through the long axis of the hippocampus. Finally, statistical analyses were performed comparing the left collateral sulcus of those with left temporal lobe epilepsy and age matched controls. Results: Of the 5 patients with left temporal lobe epilepsy 3 had left hippocampal atrophy, the other two patients had normal bilateral hippocampal volumes. The results showed significant differences in left collateral sulcus volumes between those with left temporal lobe epilepsy and age matched controls (p=0.029). Conclusions: This study was performed to investigate if an abnormally shaped collateral sulcus showed changes in volume in patients with epilepsy compared to controls. These findings suggest that other areas outside of the hippocampus may be identified as being involved in the pathophysiology of epilepsy. In addition to previous findings of abnormal shape and positioning of the collateral sulcus, the volume of the collateral sulcus may be increased as a well, even in those with normal hippocampal volumes. Identifying these areas may be important in determining surgically amenable regions to reduce seizure frequency in those with temporal lobe epilepsy.
Neuroimaging