Division of Nuclear Medicine and Molecular Imaging, The Russell H. Morgan Department of Radiology and Radiological Science, Johns Hopkins University School of Medicine, 601 N. Caroline St, Baltimore, MD, 21287, USA.
Department of Neurology, Johns Hopkins University School of Medicine, Baltimore, USA.
Ann Nucl Med. 2023 Sep;37(9):528-534. doi: 10.1007/s12149-023-01853-w. Epub 2023 Jun 28.
Anti-glutamic acid decarboxylase 65 (anti-GAD65)-associated neurological disorders include two major phenotypes, namely Stiff person syndrome (SPS) and cerebellar ataxia (CA). Considering the potential for better outcomes with prompt immunotherapy, early detection of CA is crucial. Hence, a non-invasive imaging biomarker to detect CA with high specificity is desired. Herein, we evaluated brain 2-deoxy-2-[F]fluoro-D-glucose (F-FDG) PET in detecting CA based on cerebellar uptake using receiver operating characteristic (ROC) analysis and five-fold cross-validation.
This study was based on STARD 2015 guidelines: thirty patients with anti-GAD65-associated neurological disorders, 11 of whom with CA were studied. Five test sets were created after patients were randomly sorted and divided into 5 equal folds. Each iteration included 24 patients for ROC analysis and 6 patients reserved for testing. The Z scores of left cerebellum, vermis, right cerebellum, and the average of the three regions were used in ROC analysis to determine areas with significant area under the curve (AUC). The cut-off values with high specificity were determined among the 24 patients in each iteration and tested against the reserved 6 patients.
Left cerebellum and average of the three regions showed significant AUC above 0.5 in all iterations with left cerebellum being the highest AUC in 4 iterations. Testing the cut-off values of the left cerebellum against the reserved 6 patients in each iteration showed 100% specificity with sensitivities ranging from 0 to 75%.
Cerebellar F-FDG PET uptake can differentiate CA phenotypes from patients with SPS with high specificity.
抗谷氨酸脱羧酶 65（anti-GAD65）相关神经疾病包括两种主要表型，即僵人综合征（SPS）和小脑共济失调（CA）。鉴于及时免疫治疗可能有更好的效果，因此早期发现 CA 至关重要。因此，需要一种具有高特异性的非侵入性成像生物标志物来检测 CA。在此，我们使用接受者操作特征（ROC）分析和五倍交叉验证评估了脑 2-脱氧-2-[F]氟-D-葡萄糖（F-FDG）PET 在检测 CA 方面的作用，其依据是小脑摄取情况。
本研究基于 STARD 2015 指南：30 名患有抗-GAD65 相关神经疾病的患者，其中 11 名患有 CA。患者随机排序并分为 5 个相等的折叠后，创建了 5 个测试集。每个迭代都包含 24 名患者进行 ROC 分析和 6 名患者用于测试。ROC 分析中使用左小脑、蚓部、右小脑和三个区域的平均值的 Z 分数来确定具有显著曲线下面积（AUC）的区域。在每个迭代的 24 名患者中确定具有高特异性的截止值，并与保留的 6 名患者进行测试。
左小脑和三个区域的平均值在所有迭代中均显示出 AUC 显著高于 0.5，其中左小脑在 4 个迭代中 AUC 最高。在每个迭代中，将左小脑的截止值与保留的 6 名患者进行测试时，特异性为 100%，灵敏度范围为 0 至 75%。
小脑 F-FDG PET 摄取可以高特异性地区分 CA 表型与 SPS 患者。
