An Unusual case of Reversible Cerebral Vasoconstriction Syndrome

A 25 year old pregnant lady (36 weeks of amenorrhea) presented with acute onset headache, vomiting followed by generalised seizures and progressive altered sensorium over 24 hours. Her Blood pressure was 190 110mmHg and was diagnosed to have eclampsia, initiated on Magnesium sulfate and underwent lower segment caesarian section. She was imaged with MRIMRA with diffusion study which showed right occipital and bilateral cerebellar hyperintensities with areas of restriction of diffusion and diffuse narrowing of vessels of the vertebrobasilar system. There was distortion of brainstem and 4th ventricle with obstructive hydrocephalus. She underwent an External Ventricular Drainage (EVD) followed by posterior fossa decompressive craniectomy. Over 96 hours, her sensorium had improved to a GCS of 15.Repeat MR Imaging showed resolution of cerebellar hyperintensities and normalization of the diffusion restriction, with normal vessels on MR angiogram. Subsequent transcranial doppler of vertebrobasilar arteries was also normal. Based on the clinical setting of headache, raised blood pressure in the peripartum period and the serial imaging findings, reversible cerebral vasoconstriction syndrome was diagnosed. The atypical features in this case were the hyper acute presentation progressing to coma within 24 hours, the initial MRI showing diffusion restriction, with significant mass effect and obstructive hydrocephalus requiring posterior fossa decompression and disease process being confined to the posterior circulation.