Intravascular lymphomatosis presenting as acute hemispheric dysfunction

Intravascular lymphomatosis (IVL) is known to affect both hemispheres of the brain and manifests clinically as seizures or dementia. To our knowledge, there have been no cases in which acute hemispheric dysfunction is manifested in IVL. We present a 54-year-old man who showed steroid responsive acute hemispheric dysfunction. A technetium 99m-ethyl cysteinate dimer single-photon emission computed tomographic scan of the brain revealed hypoperfusion in the right hemisphere. The bone marrow biopsy specimen confirmed malignant lymphoid cells in vessels, which suggested IVL. Our case signifies the diversity of clinical manifestations in IVL.