Primary angiitis of the central nervous system at conventional angiography.

PURPOSE: To retrospectively determine the sensitivity and specificity of cerebral angiography for the diagnosis of primary angiitis of the central nervous system (CNS).
MATERIALS AND METHODS: Institutional review board approval was obtained, and informed consent was not required. Thirty-eight patients (13 men, 25 women; mean age, 55 years) had undergone cerebral angiography followed by cortical and leptomeningeal biopsy for possible primary angiitis of the CNS during an 8-year period. Angiography reports were reviewed by investigators blinded to the results of biopsy. Angiographic findings were categorized as typical for vasculitis, normal, or other. Sensitivity and specificity of cerebral angiography for the diagnosis of primary angiitis of the CNS were calculated.
RESULTS: Fourteen patients had typical angiographic findings of vasculitis. None had primary angiitis of the CNS at brain biopsy (60% specificity). Specific pathologic diagnoses other than primary angiitis of the CNS were made in six patients. Findings of brain biopsy in the remaining eight patients were nondiagnostic. Repeat angiograms were obtained in three of the eight patients. One patient demonstrated interval improvement in multiple focal intracranial arterial stenoses and two demonstrated worsening. Primary angiitis of the CNS was found at biopsy in two of the remaining 24 patients (0% sensitivity). One of the two patients had slow filling of a single distal cortical artery, and the other patient had multiple regions of abnormally prolonged capillary blush.
CONCLUSION: In this series, patients suspected of having primary angiitis of the CNS on the basis of clinical and angiographic findings did not have primary angiitis of the CNS at biopsy. Typical angiographic findings of primary angiitis of the CNS are often associated with other specific pathologic diagnoses, which emphasizes the importance of brain biopsy. (c) RSNA, 2004.