Department of Radiology, Research Institute of Radiological Science, Severance Hospital, Yonsei University College of Medicine, 50-1 Yonsei-ro, Seodaemun-gu, Seoul, 03722, Republic of Korea.
Department of Radiology, Seoul National University College of Medicine, Institute of Radiation Medicine, Seoul National University Medical Research Center, Cancer Research Institute, Seoul National University, Seoul, Republic of Korea.
Eur Radiol. 2021 Feb;31(2):1130-1139. doi: 10.1007/s00330-020-07173-1. Epub 2020 Aug 19.
To determine whether quantitative radiomic features from cardiac CT could differentiate the left atrial appendage (LAA) thrombus from circulatory stasis in patients with valvular heart disease.
Ninety-five consecutive patients with valvular heart disease and filling defects in LAA on two-phase cardiac CT from March 2016 to August 2018 were retrospectively enrolled and classified as having thrombus or stasis by transesophageal echocardiography or cardiac surgery. The ratio of Hounsfield units in the filling defects to those in the ascending aorta (AA) was calculated on early- and late-phase CT (LAA/AA and LAA/AA, respectively). Radiomic features were extracted from semi-automated three-dimensional segmentation of the filling defect on early-phase CT. The diagnostic ability of radiomic features for differentiating thrombus from stasis was assessed and compared to LAA/AA and LAA/AA by comparing the AUC of ROC curves. Diagnostic performances of CT attenuation ratios and radiomic features were validated with an independent validation set.
Thrombus was diagnosed in 25 cases and stasis in 70. Sixty-eight radiomic features were extracted. Values of 8 wavelet-transformed features were lower in thrombus than in stasis (p < 0.001). The AUC value of a radiomic feature, wavelet_LHL, for diagnosing thrombus was 0.78, which was higher than that of LAA/AA (AUC = 0.54, p = 0.025) and similar to that of LAA/AA (AUC = 0.76, p = 0.773). In the validation set, the AUC of wavelet_LHL was 0.71, which was higher than that of LAA/AA (AUC = 0.57, p = 0.391) and similar to that of LAA/AA (AUC = 0.75, p = 0.707).
Quantitative radiomic features from the early phase of cardiac CT may help diagnose LAA thrombus in patients with valvular heart disease.
• Wavelet-transformed grey-level non-uniformity values from radiomic analysis are significantly lower for LAA thrombus than for circulatory stasis. • Radiomic features may have an additional value for differentiating LAA thrombus from circulatory stasis when interpreting single-phase cardiac CT. • Radiomic features extracted from single-phase images may show similar diagnostic ability as conventional quantitative analysis from two-phase images.
确定心脏 CT 的定量放射组学特征是否可以区分瓣膜性心脏病患者左心耳（LAA）血栓与循环淤滞。
回顾性纳入 2016 年 3 月至 2018 年 8 月期间，95 例经心脏 CT 证实存在二尖瓣和（或）三尖瓣病变且 LAA 内存在充盈缺损的患者，经食管超声心动图或心脏手术证实充盈缺损为血栓或淤滞。计算早期和晚期 CT 上充盈缺损的 CT 值与升主动脉（AA）CT 值的比值（LAA/AA 和 LAA/AA）。使用早期 CT 上的半自动三维分割对充盈缺损进行放射组学特征提取。通过比较 ROC 曲线的 AUC，评估放射组学特征在区分血栓与淤滞方面的诊断能力，并与 LAA/AA 和 LAA/AA 进行比较。使用独立验证集验证 CT 衰减比和放射组学特征的诊断性能。
25 例诊断为血栓，70 例诊断为淤滞。提取了 68 个放射组学特征。血栓组 8 个小波变换特征的取值低于淤滞组（p < 0.001）。放射组学特征 wavelet_LHL 诊断血栓的 AUC 值为 0.78，高于 LAA/AA（AUC = 0.54，p = 0.025），与 LAA/AA（AUC = 0.76，p = 0.773）相似。在验证集中，wavelet_LHL 的 AUC 值为 0.71，高于 LAA/AA（AUC = 0.57，p = 0.391），与 LAA/AA（AUC = 0.75，p = 0.707）相似。
瓣膜性心脏病患者心脏 CT 早期的定量放射组学特征可能有助于诊断 LAA 血栓。
放射组学分析的小波变换灰度不均匀性值在 LAA 血栓中明显低于循环淤滞。
在解释单相心脏 CT 时，放射组学特征在区分 LAA 血栓与循环淤滞方面可能具有附加价值。
从单相图像中提取的放射组学特征可能与从双相图像中提取的传统定量分析具有相似的诊断能力。
