The spot sign on CTA has been previously correlated with hematoma expansion, mortality, and poor clinical outcomes in patients with primary ICH. In practice, the CTA spot sign is likely to be of greatest relevance, given hyperacute stroke imaging is still largely predicated on CT imaging. However, MR imaging has increasingly been used early in the course of acute stroke imaging, but there is no equivalent sign that has been validated. Here, the authors report on an equivalent MR spot sign on contrast enhance T1 weighted imaging in 50 consecutive primary ICH patients presenting within 24 hours of an acute stroke syndrome. 

Contrast enhancement within the hematoma on MR (spot sign) was demonstrated in 23 of 50 patients (46%) with primary ICH. Larger spot signs were seen with larger hematomas and correlated with the outcome based on mRS; specifically when spot signs were dichotomized as large (> 1 mL) vs small (< 1mL), large spot signs were characterized by larger hematoma volumes (36 mL vs 5 mL) and worse outcomes (median mRS 5). When patients were dichotomized according to presence or absence of a spot sign, patients with the spot sign had worse outcomes (median mRS 4) despite similar NIHSS on admission. On follow up imaging, however, no significant difference was seen in regards to hematoma expansion between those who had a spot sign and those who did not.

Although the MR spot sign was not demonstrated to be predictive of hematoma expansion, it was predictive of clinical outcome. Given that MR allows evaluation of hematoma age and often provides additional information on possible etiology of hemorrhage, the validation of an equivalent spot sign on MR adds another tool to the arsenal of MR interpretation for ICH.