In the United States, 1–8% of<unk>  patients are diagnosed with<unk>  disease, with approximately 110,000 cases per year. The exact incidence of<unk>  disease is difficult to determine, since gross examination at autopsy may overlook signs of<unk>  disease, and microscopic pathological inspection may be normal if the seeding is multifocal or if an unaffected area of the central nervous system (CNS) is examined.
Leptomeningeal cancer
Brain metastasis
Brain abscess
Amoebic brain abscess
Lymphocytic meningoradiculitis
Primary central nervous system lymphoma
Malignant multiple sclerosis
Central nervous system cavernous hemangioma