Diagnostic and Interventional Radiology and Molecular Imaging Department, Faculty of Medicine, Ain Shams University, Cairo, Egypt.
Pediatric Hematology Oncology and BMT Department, Faculty of Medicine, Ain Shams University, Cairo, Egypt.
Magn Reson Imaging. 2024 Dec;114:110250. doi: 10.1016/j.mri.2024.110250. Epub 2024 Oct 3.
The T2* technique, used for quantifying myocardial iron content (MIC), has limitations in detecting early myocardial iron overload (MIO). The in vivo mapping of the myocardial T1 relaxation time is a promising alternative for the early detection and management of MIO.
32 β-thalassemia major (βTM) patients aged 11.5 ± 4 years and 32 healthy controls were recruited and underwent thorough clinical and laboratory assessments. The mid-level septal iron overload was measured through T1 mapping using a modified Look-Locker inversion recovery sequence with a 3 (3 s) 3 (3 s) 5 scheme. Septum was divided at the mentioned level into 3 zones corresponding to segments 8 and 9 in the cardiac segmentation model.
21.9 % of βTM had clinical cardiac morbidity. The cut-off of T1 mapping of hepatic and myocardium to differentiate between the patients and control groups was ≤466 and ≥ 923 ms respectively. The T1 technique was able to detect 4 patients with high MIC, two of them were not detected by the T2* technique. There was a statistically significant correlation between the average T1 values of the studied zones in patients with βTM and the liver iron content (LIC), the T1 values within segment 8 of the liver, age of patients, the age at first transfusion, age of splenectomy and serum ferritin value.
The addition of the T1 mapping sequence to the conventional T2* technique was able to increase the efficacy of the MIC detection protocol by earlier detection of MIO. This would guide chelation therapy to decrease myocardial morbidity.
用于量化心肌铁含量（MIC）的 T2*技术在检测早期心肌铁过载（MIO）方面存在局限性。心肌 T1 弛豫时间的体内映射是早期检测和管理 MIO 的有前途的替代方法。
招募了 32 名年龄为 11.5±4 岁的β地中海贫血症（βTM）患者和 32 名健康对照者，并进行了全面的临床和实验室评估。使用改良的 Look-Locker 反转恢复序列通过 T1 映射测量中隔铁过载，该序列具有 3（3 s）3（3 s）5 方案。中隔在所述水平上分为 3 个区，对应于心脏分段模型中的节段 8 和 9。
21.9%的βTM 有临床心脏发病。区分患者和对照组的肝脏和心肌 T1 映射的截止值分别为≤466 和≥923 ms。T1 技术能够检测到 4 名 MIC 较高的患者，其中 2 名未被 T2*技术检测到。βTM 患者研究区的平均 T1 值与肝脏铁含量（LIC）、肝脏节段 8 内的 T1 值、患者年龄、首次输血年龄、脾切除术年龄和血清铁蛋白值之间存在统计学显著相关性。
将 T1 映射序列添加到常规 T2*技术中，可以通过更早地检测 MIO 来提高 MIC 检测方案的功效。这将指导螯合治疗以减少心肌发病。
