Murray Valley encephalitis: case report and review of neuroradiological features.

We report on a child with diffuse symmetrical thalamic enlargement and signal increase on MRI, representing changes caused by Murray Valley encephalitis (MVE). Very little has previously been reported on the neuroradiological findings of MVE, also known as Australian encephalitis. It is endemic to tropical North Australia, particularly Western Australia and the Northern Territory, but can occur in other parts of Australia. The last epidemic was in south-eastern Australia in 1974. Australian encephalitis is the second most serious acute viral encephalitis to be encountered in Australia. Clinicians need to be aware of MVE in this era of ever-increasing travel. Our aim is to highlight these finding and further define the neuroradiological features.