Abstract
PURPOSE: To evaluate MR characteristics of acute disseminated encephalomyelitis (ADEM) in children, which
was confirmed by clinical findings.
MATERIALS AND METHODS: The subjects were six patients, who were diagnosed by clinical findings. One subject
had recurrence one year after clinical improvement leading to one additional care with the total of seven.
The modes of viral infections were as follows;four cases of non-specific upper respiratory tract infection, one of
E-B virus, one of Japanese-B-encephalitis vaccination, and one of upper respiratory infection in Bruton's
disease. The Gd-DTPA enhanced scan was performed in all cases. MR findings were evaluated in anatomic
location of the lesions, presence or absence of contrast enhancement, and the temporal changes were also
evaluated on follow-up MRI.
RESULT: There were multifocal high signal intensity lesions on T2WI in all cases. The location of lesions were
basal ganglia in five, thalamus and brain stem in four, and cerebral gray and white matter and cerebellar white
matter in three. Bilaterality was 77%. There were contrast enhancement in two of three cerebral cortical
lesions and one of three white matter lesions. The size of lesions decreased on the first follow-up MRI which
were done after 1 month in 4 cases, but new lesions were developed in two cases. On the second follow-up
MRI which were done 2 months after, all lesions were decreased in size and there was no newly developed
lesion. However, in one case who had recurrent similar symptom after 1 year, several new lesions developed
on follow-up MRI, and it was comidened as a recurrence.
CONCLUSION: The characteristic MR findings of ADEM were multifocal bilateral white and gray matter lesions
which were high signal intensities on T2WI. The majority of lesions improved on follow-up MRI, but occasionally
showed multiphasic pattern.