Department of Radiology, Jinling Hospital, Nanjing Medical University, Nanjing, Jiangsu, China.
Department of Radiology, Jinling Hospital, Medical School of Nanjing University, Nanjing, Jiangsu, China.
J Magn Reson Imaging. 2023 Dec;58(6):1785-1796. doi: 10.1002/jmri.28684. Epub 2023 Mar 21.
Intravoxel incoherent motion (IVIM) MRI has not been widely used and its role in evaluating exertional heat illness (EHI)-related myocardial involvement remains unknown.
To investigate the feasibility of strain curve-derived trigger delay (TD) IVIM-MRI and its role in assessing myocardial diffusion and microvascular perfusion of EHI patients.
Prospective.
A total of 42 male EHI patients (median age: 21 years) and 22 age- and sex-matched healthy controls (HC).
FIELD STRENGTH/SEQUENCE: A 3-T, diffusion-weighted spin-echo echo-planar-imaging sequence.
IVIM-MRI was acquired by conventional TD method (group A) or strain curve-based TD method (group B) in random order. IVIM image quality was evaluated on a 3-point Likert scale (1, nondiagnostic; 2, moderate; 3, good). Technical success was defined as image quality score = 3. IVIM-MRI-derived parameters (pseudo diffusion in the capillaries [D*], perfusion fraction [f], and slow apparent diffusion coefficient [D]) were compared between EHI and HC.
Student's t-tests, chi-square tests, one-way analysis of variance, receiver operating characteristic (ROC) curve analysis, Pearson's correlation coefficient (r). The statistical significance level was set at P < 0.05.
IVIM-MRI image quality score (median [interquartile range]: 3 [2, 3] vs. 2 [1-3]) and technical success rate (61.9%[13/21] vs. 28.6%[6/21]) were significantly improved in group B. EHI patients showed significantly decreased D* (118.1 ± 23.3 × 10 mm /sec vs. 142.7 ± 42.6 × 10 mm /sec) and f values (0.42 ± 0.12 vs. 0.51 ± 0.11) and significantly higher D values (3.0 ± 0.9 × 10 mm /sec vs. 2.5 ± 0.6 × 10 mm /sec) compared to HC. Relative to D and D*, f showed the most robust efficacy for detecting EHI-related myocardial injury with the highest area under the ROC curve (0.906: 95% confidence interval, 0.799, 0.967) and sensitivity of 88.5% and specificity of 85.6%.
The strain curve-based TD method significantly improved image quality and technical success rate of IVIM-MRI, and f value may be an effective biomarker to assess myocardial microcirculation abnormalities of EHI patients.
Stage 3.
体素内不相干运动（IVIM）MRI 尚未得到广泛应用，其在评估与运动相关的热应激病（EHI）相关心肌受累中的作用尚不清楚。
探讨应变曲线衍生触发延迟（TD）IVIM-MRI 的可行性及其在评估 EHI 患者心肌扩散和微血管灌注中的作用。
前瞻性。
共 42 名男性 EHI 患者（中位数年龄：21 岁）和 22 名年龄和性别匹配的健康对照（HC）。
场强/序列：3.0T，扩散加权自旋回波回波平面成像序列。
通过常规 TD 方法（A 组）或应变曲线为基础的 TD 方法（B 组）以随机顺序进行 IVIM-MRI。采用 3 分李克特量表评估 IVIM 图像质量（1，无法诊断；2，中等；3，良好）。技术成功定义为图像质量评分=3。比较 EHI 和 HC 之间的 IVIM-MRI 衍生参数（毛细血管中的假扩散[D*]、灌注分数[f]和缓慢表观扩散系数[D]）。
学生 t 检验、卡方检验、单因素方差分析、受试者工作特征（ROC）曲线分析、皮尔逊相关系数（r）。统计显著性水平设为 P<0.05。
B 组 IVIM-MRI 图像质量评分（中位数[四分位距]：3[2，3]比 2[1，3]）和技术成功率（61.9%[13/21]比 28.6%[6/21]）显著提高。EHI 患者的 D*（118.1±23.3×10mm/s 比 142.7±42.6×10mm/s）和 f 值（0.42±0.12 比 0.51±0.11）显著降低，D 值（3.0±0.9×10mm/s 比 2.5±0.6×10mm/s）显著升高，与 HC 相比。与 D 和 D*相比，f 显示出检测 EHI 相关心肌损伤的最高功效，ROC 曲线下面积最高（0.906：95%置信区间，0.799，0.967），灵敏度为 88.5%，特异性为 85.6%。
应变曲线为基础的 TD 方法显著提高了 IVIM-MRI 的图像质量和技术成功率，f 值可能是评估 EHI 患者心肌微循环异常的有效生物标志物。
2。
3 级。
