Diagnostic value of single-photon-emission computed tomography in severe central nervous system involvement of systemic lupus erythematosus: a case-control study.

OBJECTIVE: To evaluate the diagnostic value of single-photon-emission computed tomography (SPECT) in severe central nervous system (CNS) involvement of systemic lupus erythematosus (SLE).

METHODS: Forty-three patients with SLE, including 22 with CNS-SLE and 21 with non-CNS-SLE, underwent SPECT and magnetic resonance imaging (MRI) examinations. SPECT was repeated 1-2 months after treatment in patients with abnormal findings.

RESULTS: SPECT and MRI abnormalities were detected in 20 (90.9%) and 10 (45.5%) of the 22 patients with CNS-SLE, respectively (P < 0.01). For 4 patients with cerebral infarction or hemorrhage, SPECT was equally as sensitive as MRI (100%). For the patients with CNS-SLE with diffuse presentations, SPECT was more sensitive than MRI in revealing abnormalities (16 [88.9%] of 18 patients versus 6 [33.3%] of 18 patients; P < 0.01). In 19 (95.0%) patients, the abnormal SPECT finding manifested as moderate to severe perfusion defect (15 in frontal lobe, 11 in parietal lobe, 11 in basal ganglia, 3 in temporal lobe, and 17 in multiple regions). Although mild perfusion defect was also detected in 4 (19.0%) of the patients with non-CNS-SLE, it only involved a single region and spared the frontal and parietal lobes. Repeated SPECT after treatment showed that perfusion defect had improved significantly or even disappeared in 11 (84.6%) of 13 patients with diffuse CNS-SLE with abnormal findings before treatment.

CONCLUSION: Moderate to severe perfusion defect in SPECT involving multiple regions, especially in the frontal and parietal lobes and basal ganglia, in patients with lupus suggests CNS involvement. SPECT is more sensitive than MRI in revealing damage in diffuse CNS-SLE, and is useful in followup, especially for monitoring disease severity and guiding treatment.