Granulomatous diseases of the CNS as demonstrated by computerized tomography.

The CT findings in 32 patients with pathological conditions characterized by granulomatous disorders are reviewed. The characteristic CT finding in caseating granuloma due to tuberculous disease is a nodular enhancing lesion with a central hypodense region. The granulomas representing sarcoidosis show homogeneous enhancing nodular lesions. The granulomas due to cryptococcal fungal disease showed ring pattern with large central hypodense region which represented cyst formation. In certain vasculitides which affected the CNS and had pathological evidence of granuloma formation, CT showed nodular enhancing lesions. Based upon the CT findings, it was not possible to differentiate these nodular enhancing lesions which represented granulomatous disease from other intracranial diseases, i.e. abscesses, neoplasms, multiple sclerosis, gliosis.