FIELD-STRENGTH IN MR-IMAGING OF MULTIPLE- SCLEROSIS - A COMPARISON OF0.5 AND 1.5T

The value of magnetic resonance (MR) to establish the diagnosis of mul tiple sclerosis (MS) is well known. This study was undertaken to compa re MR imaging of the brain of MS patients at high (1.5 T) and mid (0.5 T) field strength. 25 patients with MS underwent two consecutive MR s tudies within one hour, each consisting of axial proton density and T2 -weighted spin-echo images. Lesions in the supratentorial white matter and corpus callosum and those in the brain stem and cerebellum were s eparately counted. At 1.5 T significantly more lesions were seen than at 0.5 T (p < 0.05). Although T2-weighted images at 1.5 T added signif icant information compared to images obtained at 0.5 T, in none of our 25 patients the diagnosis was missed at 0.5 T. However, at 1.5 T diss emination in space was better demonstrated, suggesting MR scanning wit h high field-units to be favourable in patients with clinically suspec ted MS.