Radiological findings in neurosarcoidosis.

The radiological investigation of neurosarcoidosis is discussed in relation to a series of 32 patients presenting to a neurological hospital. Cranial computed axial tomography, performed in 13 of these cases, was the most frequently positive procedure (77%). The indications for air studies are now limited but in cases with nerve or chiasmal syndromes and negative CAT they may show small mass lesions, or incomplete filling of basal cisterns due to granulomatous infiltration or fibrosis. Sarcoid masses are avascular and angiography is only useful for exclusion of incidental tumours with pathological circulation. Cord syndromes were present in eight cases, but myelography was only indicated in five of these and was normal in three. The cord may be involved by intra-medullary granulomas or meningeal infiltration causing arachnoiditis, both of which cause myelographic abnormalities though these are not specific for sarcoidosis.