Fig 1.
The images of Tc-99m ECD brain SPECT of two patients.
(A) A 50-year-old female had occasional dizziness for one year. Brain MRI did not reveal any definite organic brain change. The autoimmune screen showed no positive autoantibody including antiphospholipid antibody. The Tc-99m ECD SPECT demonstrated only small foci of hypoperfusion at bilateral hemispheres with the coefficient of variation as 10.8%. (B) A 39-year-old female had initial presentations of depressive mood and seizure. She had positive ACA IgG, APhL IgG, anti-β2GPI IgG and lupus anticoagulants. There was no definite organic brain change in the brain MRI; however, the Tc-99m ECD SPECT revealed large areas of hypoperfusion at bilateral hemispheres with the coefficient of variation up to 20.9%. Ten months later, she developed an ischemic stroke.
Table 1.
Baseline characteristics of patients.
Table 2.
Neuropsychiatric manifestations of patients.
Fig 2.
Heterogeneity of brain perfusion.
The coefficient of variation of Tc-99m ECD SPECT signals is positively associated with the number of antiphospholipid antibodies (P = 0.01). The boxes represent interquartile range (IQR). The horizontal lines in the boxes represent median values; the horizontal lines out of the boxes represent 1.5 IQR. The black dots are outliers.