Buathong Sittaya, Piyapitayanan Siriwan, Thientunyakit Tanyaluck, Sethanandha Chakmeedaj, Muangpaisan Weerasak, Charnchaowanish Panida, Aphiwatthanasumet Kingkarn, Chawalparit Orasa, Ngamsombat Chanon
Department of Radiology, Faculty of Medicine, Siriraj Hospital, Mahidol University, Bangkok, Thailand.
Department of Preventive and Social Medicine, Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok, Thailand.
Quant Imaging Med Surg. 2025 May 1;15(5):4566-4579. doi: 10.21037/qims-24-319. Epub 2025 Apr 11.
Abnormal iron metabolism and accumulation in the brain have been proposed as pathological changes in Alzheimer's disease (AD). These changes can be detected using quantitative susceptibility mapping (QSM). The corpus callosum (CC), an essential white matter structure in the brain, is thought to undergo volume and microstructural changes in Alzheimer's patients, with specific regional atrophy related to cognitive impairment and dementia severity. This study aimed to measure susceptibility in each part of the CC in AD, mild cognitive impairment (MCI), and healthy control (HC), and assess their associations with neurocognitive scores and QSM value changes in follow-up imaging.
A retrospective study was conducted with 34 patients with AD, 32 patients with MCI, and 29 cases with HC. A subset of these participants had available follow-up magnetic resonance imaging (MRI) data, including 13 AD patients, 14 MCI patients, and 14 HC cases. Structural MRI data were processed using FreeSurfer software version 6.0 to segment the CC into five parts. QSM processing was performed using STISuite 3.0, and the results were registered and analyzed for susceptibilities in each CC segment using the FSL (FMRIB Software Library, version 5.0.7). Correlations between susceptibility levels and diagnosis were evaluated using the Kruskal-Wallis test, while associations between susceptibility and cognitive function [Thai Mental State Examination (TMSE) and Clinical Dementia Rating (CDR)] were assessed using Spearman's rank correlation coefficient. Changes after follow-up were assessed using paired samples -tests and one-way analysis of variance (ANOVA).
Significantly increased susceptibility was observed in the mid-anterior and central parts of the CC for AD patients compared to normal controls (0.051 and 0.103 ppm in AD and -0.014 and 0.003 ppm in HC; P value =0.014 and 0.009). Susceptibility in the mid-anterior, central regions, showed weakly positive correlations with CDR-global scores (r=0.296, P=0.006 and r=0.287, P=0.005). After a 2-year follow-up, susceptibility significantly increased across groups. In the HC group, significant increases were observed in the mid-anterior region (mean difference =0.074 ppm; P value =0.021). For the MCI group, a significant increase in the mid-posterior region (mean difference =0.081 ppm; P value =0.039) was found. For the AD group, a significant increase was found in the mid-posterior and posterior regions (mean difference =0.021 and 0.086 ppm; P value =0.013 and 0.005).
The study findings suggest that increased susceptibilities in the mid-anterior and central parts of the CC can serve as a potential biomarker for the diagnosis of MCI and AD and assess cognitive function in these diseases.
大脑中铁代谢异常和铁蓄积被认为是阿尔茨海默病（AD）的病理变化。这些变化可通过定量磁化率成像（QSM）检测到。胼胝体（CC）是大脑中重要的白质结构，被认为在AD患者中会发生体积和微观结构变化，特定区域萎缩与认知障碍和痴呆严重程度相关。本研究旨在测量AD、轻度认知障碍（MCI）和健康对照（HC）中CC各部分的磁化率，并评估它们与神经认知评分以及随访成像中QSM值变化的相关性。
对34例AD患者、32例MCI患者和29例HC进行回顾性研究。这些参与者中的一部分有可用的随访磁共振成像（MRI）数据，包括13例AD患者、14例MCI患者和14例HC。使用FreeSurfer软件6.0版处理结构MRI数据，将CC分为五个部分。使用STISuite 3.0进行QSM处理，并使用FSL（FMRIB软件库，5.0.7版）对每个CC节段的磁化率结果进行配准和分析。使用Kruskal-Wallis检验评估磁化率水平与诊断之间的相关性，而使用Spearman等级相关系数评估磁化率与认知功能[泰国精神状态检查（TMSE）和临床痴呆评定量表（CDR）]之间的关联。使用配对样本检验和单因素方差分析（ANOVA）评估随访后的变化。
与正常对照相比，AD患者CC的中前部和中部磁化率显著增加（AD患者分别为0.051和0.103 ppm，HC患者分别为-0.014和0.003 ppm；P值=0.014和0.009）。中前部、中部区域的磁化率与CDR整体评分呈弱正相关（r=0.296，P=0.006和r=0.287，P=0.005）。经过2年随访，各组磁化率均显著增加。在HC组中，中前部区域磁化率显著增加（平均差异=0.074 ppm；P值=0.021）。在MCI组中，中后部区域磁化率显著增加（平均差异=0.081 ppm；P值=0.
