Single‐photon–emission computed tomography analysis of cerebral blood flow in the evaluation of central nervous system involvement in patients with systemic lupus erythematosus

Objective. Single-photon–emission computed tomography (SPECT) scanning was used to detect potential central nervous system (CNS) involvement in patients with systemic lupus erythematosus (SLE), by determining cerebral blood flow abnormalities. Methods. SPECT scans were performed on 35 SLE patients, grouped into 3 categories: those without neuropsychiatric symptoms (n = 10), those with definite neurologic or psychiatric disorders (n = 10), and those with mild symptoms such as headache or memory disturbances (n = 15). SPECT scan features were classified as normal or as focal or diffuse defects in uptake. Results. SPECT findings were normal in 9 of the 10 patients without CNS symptoms, and abnormal in 9 of the 10 patients with overt neuropsychiatric disease (with motor or sensory deficits). Interestingly, only 4 of the 15 patients (26.7%) with mild symptoms suggestive of CNS disease had normal SPECT findings; the 11 remaining patients showed focal (53.3%) or diffuse (20%) uptake defects. An association between SPECT findings and disease duration was also observed, but there was no correlation of SPECT results with overall disease activity, serologic findings, or medications used. Conclusion. Our data suggest that in a substantial proportion of patients, SPECT analysis may provide additional information on potential CNS involvement, and may therefore be useful in therapeutic decisionmaking and disease monitoring in order to prevent CNS damage.