Background and purpose: The pathophysiology of the presumed perihematomal edema immediately surrounding an acute intracerebral hemorrhage is poorly understood, and its composition may influence clinical outcome. Method-Twenty-three patients from the Diagnostic Accuracy of MRI in Spontaneous intracerebral Hemorrhage (DASH) study were prospectively enrolled and studied with MRI. Perfusion-weighted imaging, diffusion-weighted imaging, and fluid-attenuated inversion recovery sequences were coregistered. TMax (the time when the residue function reaches its maximum) and apparent diffusion coefficient values in the presumed perihematomal edema regions of interest were compared with contralateral mirror and remote ipsilateral hemispheric regions of interest.
Results: Compared with mirror and ipsilateral hemispheric regions of interest, TMax (the time when the residue function reaches its maximum) and apparent diffusion coefficient were consistently increased in the presumed perihematomal edema. Two thirds of the patients also exhibited patchy regions of restricted diffusion in the presumed perihematomal edema.
Conclusions: The MRI profile of the presumed perihematomal edema in acute intracerebral hemorrhage exhibits delayed perfusion and increased diffusivity mixed with areas of reduced diffusion.