A comparison of the neuropathological effects of vigabatrin and carbamazepine in patients with newly diagnosed localization-related epilepsy using MR-based cerebral T2 relaxation time measurements.

BACKGROUND

Magnetic resonance (MR)-based T2 relaxation time measurement is a sensitive technique to detect neuropathological changes such as intramyelinic edema in vivo.

OBJECTIVE

To determine whether vigabatrin (VGB) causes an increase in T2 relaxation time in patients with newly diagnosed localization-related epilepsy over 1 year.

METHODS

Patients with newly diagnosed localization-related epilepsy who participated in a VGB-carbamazepine (CBZ) monotherapy trial were included. All were scanned on a 1.5 T Siemens SP63 Magnetom scanner. T2 maps of the brain were obtained at baseline and at follow-up 1 year later. Nine control subjects had repeated hippocampal T2 maps with a median interval of approximately 2 years.

RESULTS

23 patients (12 on VGB and 11 on CBZ) were included. There were no increased T2 relaxation times in the VGB treated group at follow-up and no significant differences between the two antiepileptic drug groups. There was a trend for the temporal and frontal white matter T2 relaxation times to be lower on follow-up in the patients compared to the control subjects.

CONCLUSION

The findings do not suggest that intramyelinic edema occurs in patients taking monotherapy VGB for 1 year.