胰腺铁沉积可引起β细胞功能障碍，导致胰岛素抵抗和分泌不足,最终引起胰腺铁沉积相关糖尿病，是目前铁过载患者日益突出的临床问题。联合祛铁治疗有助于改善糖代谢。早期诊断对调整治疗方案、疗效监测及预后评估尤为重要。MRI在胰腺铁定量评估及β细胞功能辅助评价存在一定价值，其敏感性高于空腹血糖及胰岛素测定。但R2*作为目前主要定量评估指标，受噪声、磁场不均匀性影响大，同时受成像参数影响。铁沉积所致胰腺脂肪浸润及体积萎缩又引起其定量评估变异较大。定量磁敏感性成像(QSM)是基于物质磁敏感基本特征的MRI重建技术, 不受参数影响，能够定量评估特定区域铁含量，可分离出水图、脂图，剔除脂肪干扰。本项目拟建立铁过载动物模型，以磁化率值为定量指标，通过与实际铁含量比较，探究QSM在胰腺铁定量中的价值；行静脉注射葡萄糖耐量试验（IVGTT），评价胰腺铁含量和β细胞功能之间的关系，以期为胰腺铁过载风险评估提供新手段。

Pancreatic iron accumulation induces beta-cell dysfunction, leading to insulin resistance and hyposecretion, finally causing diabetes，which gradually becomes a significant clinical problem in iron overload. Combined iron chelation has greater efficacy in promoting glucose intolerance than either chelator alone. Early diagnosis plays a crucial role in therapeutic regimen adjustment, effect motoring and prognosis evaluation. MRI is recognized as a potential modality in the diagnosis of pancreatic iron overload and the assistant evaluation of beta-cell function, with higher sensitivity than fasting glucose and insulin. R2*, as the main MRI indicator for iron quantitation, is susceptible to magnetic inhomogeneity, as well as imaging parameters. Meanwhile, great variability induced by fat gland infiltration and volume shrinking poses a great challenge for clinical application. Based on the materials’ fundamental susceptibility, quantitative susceptibility mapping (QSM) is developed as a new technique for quantifying iron deposits, not subjected to imaging parameters. Water and fat images are reconstructed from the source images, thus results are free from fat infiltration. Compared with real pancreatic iron concentration, our study intends to investigate the value of QSM in pancreatic iron overload with quantitative susceptibility value. We expect to explore the relationship between pancreatic iron accumulation and beta-cell function, evaluated by intravenous glucose tolerance test（IVGTT）,aiming at a new method for risk assessment.