Zorzi Giovanni, Gazzola Gianmarco, Rossato Francesco, Bussè Cinzia, Camporese Giulia, Cecchin Diego, Cagnin Annachiara
Padova Neuroscience Center (PNC), University of Padova, Padova, Italy.
Neurology, Department of Neuroscience, University of Padova, Padova, Italy.
Eur J Neurol. 2025 Jan;32(1):e70015. doi: 10.1111/ene.70015.
Brain [18F]FDG-PET is a supportive biomarker for cognitive impairment in Lewy bodies disease (LBD) showing reduced occipital metabolism and presence of the cingulate island sign (CIS), a relative preservation of posterior cingulate cortex (PCC) metabolism compared with precuneus and cuneus. We assess validation, clinical utility, and reproducibility of a qualitative visual CIS scale in the differential diagnosis with Alzheimer's disease (AD) in a memory clinic setting.
Sixty-seven patients were studied: 36 LBD, of whom 30 with dementia (DLB) and 6 with mild cognitive impairment (MCI-LB), and 31 AD (20 typical and 11 atypical presentations). They underwent FDG-PET/MRI scans and were followed for at least 24 months. The visual CIS rating scale was scored by a nuclear medicine physician and a neurologist independently. Qualitative CIS scores were validated with ROI-based semiquantitative FDG analysis.
Mean CIS scores were 1.84 ± 1.69 for LBD and 0.9 ± 1.24 for AD (p = 0.001). With a cutoff CIS score ≥2, sensitivity was 0.56, and specificity 0.81 (accuracy 0.67). Positive CIS in patients with AD was due to atypical presentations. Negative CIS in LBD was due to (i) normal FDG-PET in MCI-LB or (ii) marked hypometabolism of both the PCC and cuneus. Visual CIS scores correlated with FDG-uptake (r = 0.45; p < 0.001) and held a high inter-specialists concordance.
The visual CIS scale can be successfully scored by different specialists. Lower sensitivity is expected in cases of MCI-LB or dementia due to mixed LBD/AD changes. Specificity may be influenced by the inclusion of atypical AD cases.
脑[18F]氟代脱氧葡萄糖正电子发射断层扫描（FDG-PET）是路易体病（LBD）认知障碍的一种辅助生物标志物，表现为枕叶代谢降低和扣带回岛征（CIS），即与楔前叶和楔叶相比，后扣带回皮质（PCC）代谢相对保留。我们在记忆门诊环境中评估了一种定性视觉CIS量表在与阿尔茨海默病（AD）鉴别诊断中的有效性、临床实用性和可重复性。
对67例患者进行了研究：36例LBD患者，其中30例患有痴呆（DLB），6例患有轻度认知障碍（MCI-LB），以及31例AD患者（20例典型表现和11例非典型表现）。他们接受了FDG-PET/MRI扫描，并随访至少24个月。视觉CIS评分量表由一名核医学医师和一名神经科医生独立评分。定性CIS评分通过基于感兴趣区（ROI）的FDG半定量分析进行验证。
LBD患者的平均CIS评分为1.84±1.69，AD患者为0.9±1.24（p = 0.001）。以CIS评分≥2为临界值，敏感性为0.56，特异性为0.81（准确性为0.67）。AD患者的阳性CIS是由于非典型表现。LBD患者的阴性CIS是由于（i）MCI-LB患者的FDG-PET正常，或（ii）PCC和楔叶均有明显代谢减低。视觉CIS评分与FDG摄取相关（r = 0.45；p < 0.001），且专家间一致性较高。
不同专家能够成功地对视觉CIS量表进行评分。在MCI-LB或由LBD/AD混合变化导致的痴呆病例中，预计敏感性较低。特异性可能会受到非典型AD病例纳入的影响。
