Acute disseminated encephalomyelitis: clinical and MRI study from South India

Clinical and MRI appearances were reviewed in 25 cases of acute disseminate d encephalomyelitis (ADEM) seen in a university hospital in South India. Sp ecific viral infections and Semple antirabies vaccination together accounte d for 56% of antecedent events. Clinical and MRI features were suggestive o f diffuse/multifocal form in 15 patients. Of the 10 patients with clinicall y site restricted forms, two patients with dorsal myelitis and one patient with polyradiculitis had asymptomatic cerebral white matter lesions. MRI wa s essentially normal in all the four patients with acute ataxia following v aricella infection. Of the 13 patients with multiple white matter lesions, lesions were asymmetrical in size and morphology in nine patients and symme trical in four patients. Two of them had extensive destructive lesions and one patient had multiple discrete lesions. Lesions occurred at the corticom edullary junctions in seven patients. The distribution was subcortical and/ or centrum semiovale in 10 patients. The regions affected include internal capsule(s), thalami, brainstem, cerebellar peduncles and cerebellum. No spe cific differences were observed in patients with ADEM following specific vi ral infections, Semple antirabies vaccination, and nonspecific upper respir atory tract infections There was fairly good correlation between clinical a nd MRI findings in 81% of patients. Patients with incomplete recovery showe d extensive and/or multifocal lesions. (C) 1999 Elsevier Science B.V. All r ights reserved.