Susac syndrome in a young child.

Susac syndrome is a microangiopathy of unknown origin affecting the brain, retina and inner ear. This rare entity is often misdiagnosed as a demyelinating condition such as multiple sclerosis or acute disseminated encephalomyelitis. A high index of suspicion must be present as the majority of patients do not have the complete clinical triad at the time of onset of symptoms. The radiologist plays an important role when the disease is suspected and helps orient the investigations. The syndrome has characteristic imaging features on MRI that include multifocal white matter and occasional grey matter lesions, the corpus callosum being always involved. The predominant central callosal lesions, especially with rapid cystic transformation (central callosal holes) can be considered pathognomonic of this condition in the appropriate clinical setting. This disease is extremely rare in children. We report a case of Susac syndrome in a 9-year-old girl to increase the awareness among paediatric radiologists of this entity, which is usually not considered as a differential diagnosis of multifocal white matter involvement in this age group.