MRI characteristics of spontaneous intracerebral hemorrhage

We review the signal characteristics of intracerebral hematomas (ICH) on ma gnetic resonance imaging (MRI), with special emphasis on the diagnosis of i ntracerebral hemorrhage within the first hours after stroke. The detection of peracute ICH was evaluated in 42 patients of a prospective , MR randomized stroke trial. These patients underwent a protocol of T1 and T2 weighted sequences, diffusion weigthed sequences and MR - angiography w ithin 6 hours after onset of acute hemiparesis. The signal behaviour of ICH in any stage after bleeding was additionally reviewed in a retrospective s eries of 63 patients, who were submitted for MRI over a 12 months period be cause of known ICH. MRI correctly identified 4 hyperacute ICH in the prospective group and 4 hy peracute ICH in the retrospective group. These ICHs had high signal on TZ w eighted images, were isointense in T1 weighted images and had signal voids on the diffusion weighted sequences. The signal intensities of acute, subac ute and chronic ICHs correlated to previous experiences as reported in the literature. In conclusion, MRI reliably identified all hematomas even in the hyperacute stage. Diffusion weighted images were most sensitive to the presence of de oxyhemoglobine and helpful for the differentiation and characterization of acute ischemia. Therefore, MRI at 1.5 T can be employed as an alternative t o CT for the emergency diagnosis of acute stroke.