Department of Diagnostic Radiology, Mansoura University, Egypt.
Acad Radiol. 2011 Jan;18(1):70-3. doi: 10.1016/j.acra.2010.08.023.
To evaluate the effect of levodopa on apparent diffusion coefficient (ADC) value of the brain parenchyma in patients with idiopathic Parkinson disease (PD).
Prospective study was conducted on native PD without treatment (n = 25) and patients receiving levodopa (L-Dopa) (n = 25). Diffusion magnetic resonance-weighted imaging was done using a single-shot spin echo type of echo planar imaging. The apparent diffusion coefficient (ADC) value at different regions of the brain on both sides was calculated.
The ADC value of the putamen in patients with native PD was 0.732 ± 0.15 × 10-3 mm2/seconds and in patients receiving levodopa was 0.789 ± 0.24 × 10-3 mm2/second. There was a statistically significant difference in the ADC value at the putamen (P = .001) between patients with native PD and patients receiving levodopa. When ADC value of the putamen at 0.745 × 10-3 mm2/second was used as a threshold value for differentiating native PD patients and patients receiving L-Dopa, the best results were obtained with an accuracy of 82%, sensitivity of 92%, specificity of 72%, positive predictive value of 77%, negative predictive value of 90%, and area under the curve of 0.955.
ADC value of the putamen is a promising parameter for predication of effect of levodopa on brain parenchyma in patients with PD.
评估左旋多巴对特发性帕金森病（PD）患者脑实质表观扩散系数（ADC）值的影响。
对未经治疗的原发性 PD 患者（n=25）和接受左旋多巴（L-Dopa）治疗的患者（n=25）进行了前瞻性研究。使用单次激发自旋回波型 echo 平面成像进行扩散磁共振加权成像。计算双侧大脑不同区域的表观扩散系数（ADC）值。
未经治疗的 PD 患者壳核的 ADC 值为 0.732±0.15×10-3mm2/秒，接受 L-Dopa 治疗的患者为 0.789±0.24×10-3mm2/秒。壳核 ADC 值在未经治疗的 PD 患者和接受 L-Dopa 治疗的患者之间存在统计学显著差异（P=0.001）。当壳核 ADC 值为 0.745×10-3mm2/秒作为区分未经治疗的 PD 患者和接受 L-Dopa 治疗的患者的阈值时，获得了最佳的结果，准确率为 82%，灵敏度为 92%，特异性为 72%，阳性预测值为 77%，阴性预测值为 90%，曲线下面积为 0.955。
壳核 ADC 值是预测 PD 患者脑实质对左旋多巴治疗效果的一个有前途的参数。
