Berti Valentina, Pupi Alberto, Ramat Silvia, Vanzi Eleonora, De Cristofaro Maria Teresa, Pellicanò Giannantonio, Mungai Francesco, Marini Paolo, Sorbi Sandro
Clinical Pathophysiology, University of Florence, Florence, Italy.
Eur J Nucl Med Mol Imaging. 2008 Dec;35(12):2220-6. doi: 10.1007/s00259-008-0872-4. Epub 2008 Jul 23.
The aim of this study was to evaluate the accuracy of different single-photon emission computed tomography (SPECT) reconstruction techniques in measuring striatal N-omega-fluoropropyl-2beta-carbomethoxy-3beta-4-[(123)I]iodophenyl-nortropane ((123)I-FP-CIT) binding in de novo Parkinson's disease (PD) patients, in order to find a correlation with clinical scales of disease severity in the initial phases of disease.
Thirty-six de novo PD patients underwent (123)I-FP-CIT SPECT and MRI scan. SPECT data were reconstructed with filtered back projection (FBP), with an iterative algorithm (ordered subset expected maximization, OSEM) and with a method previously developed in our institution, called least-squares (LS) method. The ratio of specific to non-specific striatal (123)I-FP-CIT binding (binding potential, BP) was used as the outcome measure with all the reconstruction methods (BP(FBP), BP(OSEM), BP(LS)).
The range of values of striatal BP(LS) was significantly greater than BP(FBP) and BP(OSEM). For all striatal regions, estimates of BP(FBP) correlated well with BP(OSEM) (r = 0.84) and with BP(LS) (r = 0.64); BP(OSEM) correlated significantly with BP(LS) (r = 0.76). A good correlation was found between putaminal BP(LS) and Hoen and Yahr, Unified PD Rating Scale (UPDRS) and lateralized UPDRS motor scores (r = -0.46, r = -0.42, r = -0.39, respectively). Neither putaminal BP(FBP) nor putaminal BP(OSEM) correlated with any of these motor scores.
In de novo PD patients, (123)I-FP-CIT BP values derived from FBP and OSEM reconstruction techniques do not permit to differentiate PD severity. The LS method instead finds a correlation between striatal BP and disease severity scores. The results of this study support the use of (123)I-FP-CIT BP values estimated with the LS method as a biomarker of PD severity.
本研究旨在评估不同单光子发射计算机断层扫描（SPECT）重建技术在测量初发帕金森病（PD）患者纹状体N-ω-氟丙基-2β-甲氧基羰基-3β-4-[(123)I]碘苯基去甲托烷（(123)I-FP-CIT）结合情况时的准确性，以便在疾病初始阶段找到与疾病严重程度临床量表的相关性。
36例初发PD患者接受了(123)I-FP-CIT SPECT和MRI扫描。SPECT数据采用滤波反投影（FBP）、迭代算法（有序子集期望最大化，OSEM）以及我们机构之前开发的一种称为最小二乘法（LS）的方法进行重建。所有重建方法均将纹状体特异性与非特异性(123)I-FP-CIT结合的比值（结合潜力，BP）用作结果指标（BP(FBP)、BP(OSEM)、BP(LS)）。
纹状体BP(LS)的值范围显著大于BP(FBP)和BP(OSEM)。对于所有纹状体区域，BP(FBP)的估计值与BP(OSEM)（r = 0.84）以及BP(LS)（r = 0.64）均具有良好的相关性；BP(OSEM)与BP(LS)显著相关（r = 0.76）。发现壳核BP(LS)与霍恩和雅尔分级、统一PD评定量表（UPDRS）以及单侧UPDRS运动评分之间存在良好的相关性（分别为r = -0.46、r = -0.42、r = -0.39）。壳核BP(FBP)和壳核BP(OSEM)均与这些运动评分中的任何一项均无相关性。
在初发PD患者中，源自FBP和OSEM重建技术的(123)I-FP-CIT BP值无法区分PD的严重程度。相反，LS方法发现纹状体BP与疾病严重程度评分之间存在相关性。本研究结果支持将采用LS方法估计的(123)I-FP-CIT BP值用作PD严重程度的生物标志物。
