Distant Secondary Degeneration: Quantitative Evaluation of Neuron Density by 3 Tesla MRI and SPECT

I-123 iomazenil在单光子发射计算机断层扫描（SPECT）评估苯二氮卓类受体的体内具有良好的特性。利用这种配体，我们研究了单侧基底神经节或丘脑出血患者大脑皮层中枢苯二氮卓受体的分布。本研究纳入了15例高血压脑出血患者（男9例，女6例，平均年龄67.8岁）（单侧丘脑或基底神经节出血分别为10例和5例）。在出血后12 ~ 21天（平均13.7天）获得SPECT图像。我们还使用3特斯拉磁共振成像对5例患者进行了扩散张量成像以评估水的扩散率。扩散张量成像在六个非共线方向上应用扩散梯度编码。测定脑前后白质表观扩散系数（ADC）和分数各向异性（FA）值。在SPECT图像上，我们定性和定量地评估了I-123碘马西尼的累积。与对侧大脑皮层相比，出血的同侧大脑皮层中I-123 iomazenil的积累有减少的趋势。然而，同侧与对侧大脑皮质的放射性比值（I/C比值）没有明显降低。在弥散张量成像上，同侧脑白质的ADC值趋于高于对侧脑白质。同侧脑白质FA值倾向于低于对侧脑白质FA值。然而，这些变化在统计学上并不显著。在远离出血的同侧大脑皮层，中枢苯二氮卓受体I-123结合减少。在弥散张量成像上，同侧脑白质的水扩散率与对侧脑白质不同。这些结果可能提示远离丘脑或基底神经节出血的皮质神经元的潜在损伤。少

I-123 iomazenil has favorable characteristics for in vivo assessment of benzodiazepine receptors with single photon emission computed tomography (SPECT). Using this ligand, we studied the central benzodiazepine receptor distribution in the cerebral cortex in patients with unilateral basal ganglionic or thalamic hemorrhage. This study included fifteen patients (9 men, 6 women : mean age 67.8 yr) with hypertensive brain hemorrhage (10 and 5 patients with unilateral thalamic or basal ganglionic hemorrhage, respectively). SPECT images were obtained 12 to 21 days (mean : 13.7 days) after the onset of hemorrhage. We also performed diffusion tensor imaging to evaluate water diffusivity using 3 tesla MR imaging for 5 patients. Diffusion tensor imaging applied diffusion gradient encoding in six non-collinear directions. Apparent diffusion coefficient (ADC) and fractional anisotropy (FA) values were measured in the anterior and posterior cerebral white matter.On SPECT images, we evaluated the ac … More cumulation of I-123 iomazenil qualitatively and quantitatively. The accumulation of I-123 iomazenil in the ipsilateral cerebral cortex of the hemorrhage tended to be decreased in comparison with that of the contralateral cerebral cortex. However, the radioactivity ratio of the ipsilateral to the contralateral cerebral cortex (I/C ratio) was not significantly decreased. On the diffusion tensor imaging, ADC values of the ipsilateral cerebral white matter tended to be higher than those of the contralateral cerebral white matter.FA values of the ipsilateral cerebral white matter tended to be lower than those of the contralateral white matter. However, these changes were not statistically significant. Central benzodiazepine receptor I-123 iomazenil binding was decreased in the ipsilateral cerebral cortex remote from the hemorrhage. On the diffusion tensor imaging, water diffusivity of the ipsilateral cerebral white matter was different from contralateral cerebral white matter. These results would suggest the potential damage of the cortical neurons remote from thalamic or basal ganglionic hemorrhage. Less