Combined Striatal Binding and Cerebral Influx Analysis of Dynamic 11C-Raclopride PET Improves Early Differentiation Between Multiple-System Atrophy and Parkinson Disease

Journal of Nuclear Medicine

Eduard D'Hondt¹  Tjibbe de Groot¹  Koen Van Laere¹  Kristien Clerinx¹  Wim Vandenberghe¹ 

关键词: ¹¹C-raclopride;    Parkinson disease;    multiple-system atrophy;    tracer influx;    binding potential;    discriminant analysis;   

DOI  :  10.2967/jnumed.109.070144

学科分类：医学（综合）

来源: Society of Nuclear Medicine

【 摘 要 】

Striatal dopamine D2 receptor (D2R) PET has been proposed to differentiate between Parkinson disease (PD) and multiple-system atrophy with predominant parkinsonism (MSA-P). However, considerable overlap in striatal D2 binding may exist between PD and MSA-P. It has been shown that imaging of neuronal activity, as determined by metabolism or perfusion, can also help distinguish PD from MSA-P. We investigated whether the differential diagnostic value of 11C-raclopride PET could be improved by dynamic scan analysis combining D2R binding and regional tracer influx. Methods: 11C-raclopride PET was performed in 9 MSA-P patients (mean age ± SD, 56.2 ± 10.2 y; disease duration, 2.9 ± 0.8 y; median Hoehn-Yahr score, 3), 10 PD patients (mean age ± SD, 65.7 ± 8.1 y; disease duration, 3.3 ± 1.5 y; median Hoehn-Yahr score, 1.5), and 10 healthy controls (mean age ± SD, 61.6 ± 6.5 y). Diagnosis was obtained after prolonged follow-up (MSA-P, 5.5 ± 2.0 y; PD, 6.0 ± 2.3 y) using validated clinical criteria. Spatially normalized parametric images of binding potential (BP) and local influx ratio (R1 = K1/K′1) of 11C-raclopride were obtained using a voxelwise reference tissue model with occipital cortex as reference region. Stepwise forward discriminant analysis with cross-validation, with and without the inclusion of regional R1 values, was performed using a predefined volume-of-interest template. Results: Using conventional BP values, we correctly classified 65.5% (all values given with cross-validation) of 29 cases only. The combination of BP and R1 information increased discrimination accuracy to 79.3%. When healthy controls were not included and patients only were considered, BP information alone discriminated PD and MSA-P in 84.2% of cases, but the combination with R1 data increased accuracy to 100%. Conclusion: Discriminant analysis using combined striatal D2R BP and cerebral influx ratio information of a single dynamic 11C-raclopride PET scan distinguishes MSA-P and PD patients with high accuracy and is superior to conventional methods of striatal D2R binding analysis.

【 授权许可】

Unknown