LAUSR

Purpose Whereas SPECT images obtained 180 minutes after administration of 123I-iomazenil (IMZ) (late images) are proportional to the distribution of central benzodiazepine receptor–binding potential, SPECT images obtained within 30 minutes after 123I-IMZ administration (early images) correlate with regional brain perfusion. The aim of the present study was to determine whether crossed cerebellar tracer uptake on acute-stage 123I-IMZ SPECT imaging predicts 3-month functional outcome in patients with nonfatal hypertensive putaminal or thalamic hemorrhage. Methods Forty-six patients underwent early and late SPECT imaging with 123I-IMZ within 7 days after the onset of hemorrhage. A region of interest was automatically placed in the bilateral cerebellar hemispheres using a 3-dimensional stereotaxic region-of-interest template, and the ratio of the value in the cerebellar hemisphere contralateral to the affected side to that in the ipsilateral cerebellar hemisphere (ARcbl) was calculated in each patient. Each patient's physical function was measured using the modified Rankin scale (mRS) score 3 months after onset. Results The ARcbl on early (&rgr; = −0.511, P = 0.0003) and late (&rgr; = −0.714, P < 0.0001) images correlated with the mRS 3 months after the onset of hemorrhage. Multivariate analysis showed that only a low ARcbl in late images was significantly associated with a poor functional outcome (mRS score ≥3 at 3 months after onset) (95% confidence interval, 0.001–0.003; P = 0.0212). Conclusions Crossed cerebellar tracer uptake on acute-stage 123I-IMZ SPECT imaging predicts 3-month functional outcome in patients with nonfatal hypertensive putaminal or thalamic hemorrhage.