Elysa Widjaja

Epilepsy surgery may be the only treatment option to achieve seizure freedom in patients with medically refractory localization-related epilepsy, also known as focal epilepsy. However, the success of epilepsy surgery is in part dependent on the identification of a lesion on MRI. Patients who have a lesion seen on MRI are more likely to achieve better seizure outcome following epilepsy surgery compared with those with MRI-negative epilepsy. Hence, it is crucial to improve lesion detection on MRI so as to increase the likelihood of achieving seizure freedom following epilepsy surgery. Patients with MRI-negative epilepsy are thought to have subtle focal cortical dysplasia.

My research interest is focused on improving lesion detection in children with medically refractory epilepsy and understanding the detrimental impact of epilepsy on the developing brain. In the study entitled “Diffusion Tensor Imaging Assessment of the Epileptogenic Zone in Children with Localization-Related Epilepsy”, which was published in AJNR in 2011, we used diffusion tensor imaging (DTI) to evaluate the white matter in children with MRI-visible focal cortical dysplasia and MRI-negative localization-related epilepsy. We found that DTI could identify white matter changes in children with MRI-visible focal cortical dysplasia and MRI-negative epilepsy, which corresponded to the lobar location of the epileptogenic zone

in more than half of the patients. The findings are encouraging. However, further technical development of the sequence is needed to improve the resolution of DTI while maintaining adequate signal-to-noise ratio, and further advances in image processing are needed before this technique is ready for clinical use.

In the same study on DTI assessment of the epileptogenic zone in children with localization-related epilepsy, we also found DTI changes occurring beyond the epileptogenic zone, including the contralateral hemisphere. To investigate the significance of the white matter changes, we correlated the DTI measures of white matter integrity with neurocognitive function in children with localization-related epilepsy in a subsequent study. The impairment in white matter integrity correlated with neurocognitive dysfunction. We also showed that children with localization-related epilepsy have more widespread impairment in neurocognitive function and white matter integrity than would be expected for the focal epileptogenic zone. These findings were published in Epilepsia in 2013. Further research is currently underway to advance our understanding of the impact of recurrent seizures on brain structure and function longitudinally in children.

Read this article at AJNR.org . . .