Diffusion MR Imaging of Eclampsia

Abstract

We sought to identify early and possible reversible cerebral ischemia in patients with eclampsia. Consecutive postpartum patients with a clinical diagnosis of eclampsia were examined by a neurologist to determine whether there was any neurological deficit or cognitive impairment. Patients were prospectively imaged within 48 hours of presentation and if the scans were abnormal 72 hours later. Fast spin echo T2 weighted axial and diffusion weighted axial scans were performed. The diffusion weighted scans were performed through the basal ganglia, occipital lobes and centrum semiovale. The scans were read by two neuroradiologists blinded to the patient data. Ten patients were studied. All patients had evidence of cognitive impairment. Four patients had transient hemiparesis. All patients recovered after vasodilator treatment. T2 weighted scans were abnormal in five patients with bilateral subcortical occipital hyperintense lesions. Diffusion weighted images demonstrated abnormalities in eight patients with focal hyperintense lesions in the basal ganglia, subcortical occipital poles and watershed regions of the centrum semiovale. Two patients had normal scans. Repeat imaging 72 hours later demonstrated complete resolution of the focal lesions in all eight patients. Diffusion imaging is more sensitive than T2 weighted scans in the detection of early ischemia in patients with eclampsia. Ischemia appears to be global and predominantly affects watershed regions, occipital poles and the basal ganglia. These changes appear to be completely reversible after treatment.