Acute tumor-like demyelination or demyelinating pseudotumor is a variant presentation of demyelinating diseases, such as multiple sclerosis. A 32 years old male developing left side hemiparesis for 4 days and general tonic clonic seizure lasting 2 min...
Acute tumor-like demyelination or demyelinating pseudotumor is a variant presentation of demyelinating diseases, such as multiple sclerosis. A 32 years old male developing left side hemiparesis for 4 days and general tonic clonic seizure lasting 2 minutes was admitted to the hospital. Brain magnetic resonance imaging(MRI) taken at other hospital showed a large and irregular well enhancing intra-axial mass in right fronto-parietal area with massive surrounding edema. Craniotomy was planned under the impression of the malignant glioma. The edema and hemiparesis subside by preoperative use of corticosteroid. Therefore we had to rule out lymphoma. Stereotactic biopsy revealed a demyelinating lesion consistent with demyelinating pseudotumor. The patient recovered from hemiparesis by corticosteroid treatment over several weeks. The demyelinating pseudotumor, which usually presents as a well enhancing and poorly defined intra-axial lesion with edema, is very hard to distinguish from intra-axial tumors such as lymphoma and malignant glioma. Neurosurgeons should be aware of the possibility of demyelinating pseudotumor though it is rare.