Abnormal Regional Cerebral Blood Flow Found by Technetium-99m Ethyl Cysteinate Dimer Brain Single Photon Emission Computed Tomography in Systemic Lupus Erythematosus Patients with Normal Brain Mri Findings

In this study, technetium-(99m) ethyl cysteinate dimer (Tc- 99m ECD) brain single photon emission computed tomography ( SPECT) was used to detect regional cerebral blood flow (rCBF ) of the brain in SLE patients with normal brain magnetic resonance imaging (MRI) findings. Twenty female SLE patients were enrolled in this study, divided into two groups. Group 1 consisted of 10 patients with neuropsychiatric manifestations. Group 2 consisted of 10 patients without neuropsychiatric manifestations. All patients had normal brain MRI findings. Another 10 SLE patients with abnormal MRI findings were included as group 3 for comparison. Meanwhile, 10 healthy female volunteers also underwent brain MRI and Tc-99m ECD brain SPECT for comparison. The scans revealed hypoperfusion lesions in 9/20 ( 45%) SLE patients, including 7/10 (70%) cases in group 1 and 2/10 (20%) cases in group 2. In contrast all 10 patients (100%) in group 3 had abnormal Tc-99m ECD brain SPECT findings. The parietal lobes were the most commonly involved areas. We conclude that Tc-99m ECD brain SPECT is more sensitive for detecting rCBF changes than is brain MRI in detecting the brain anatomic changes, and may have a diagnostic value in lupus cerebral involvement. However, 99mTc ECD brain SPECT may not be indicated for SLE patients with normal MRI and mild neuropsychiatric symptoms/signs, such headaches and dizziness