Data_Sheet_1_Spectral Detector CT-Derived Pulmonary Perfusion Maps and Pulmonary Parenchyma Characteristics for the Semiautomated Classification of Pulmonary Hypertension.pdf

ObjectivesTo evaluate the usefulness of spectral detector CT (SDCT)-derived pulmonary perfusion maps and pulmonary parenchyma characteristics for the semiautomated classification of pulmonary hypertension (PH).MethodsA total of 162 consecutive patients with right heart catheter (RHC)-proven PH of different aetiologies as defined by the current ESC/ERS guidelines who underwent CT pulmonary angiography (CTPA) on SDCT and 20 patients with an invasive rule-out of PH were included in this retrospective study. Semiautomatic lung segmentation into normal and malperfused areas based on iodine density (ID) as well as automatic, virtual non-contrast-based emphysema quantification were performed. Corresponding volumes, histogram features and the ID SkewnessPerfDef-Emphysema-Index (δ-index) accounting for the ratio of ID distribution in malperfused lung areas and the proportion of emphysematous lung parenchyma were computed and compared between groups.ResultsPatients with PH showed a significantly greater extent of malperfused lung areas as well as stronger and more homogenous perfusion defects. In group 3 and 4 patients, ID skewness revealed a significantly more homogenous ID distribution in perfusion defects than in all other subgroups. The δ-index allowed for further subclassification of subgroups 3 and 4 (p < 0.001), identifying patients with chronic thromboembolic PH (CTEPH, subgroup 4) with high accuracy (AUC: 0.92, 95%-CI, 0.85–0.99).ConclusionAbnormal pulmonary perfusion in PH can be detected and quantified by semiautomated SDCT-based pulmonary perfusion maps. ID skewness in malperfused lung areas, and the δ-index allow for a classification of PH subgroups, identifying groups 3 and 4 patients with high accuracy, independent of reader expertise.

研究目标：评估基于光谱检测器CT（SDCT）生成的肺灌注图及肺实质特征在肺高血压（PH）半自动分类中的实用性。研究方法：纳入了162例连续的经右心导管（RHC）证实的不同病因的PH患者，按照当前ESC/ERS指南定义，这些患者接受了SDCT肺动脉造影（CTPA）。此外，还包括了20例通过侵入性排除PH的患者。本研究采用基于碘密度（ID）的半自动肺部分段及基于虚拟非对比增强的肺气肿定量分析。计算并比较了相应体积、直方图特征以及考虑了不良灌注肺区ID分布比率和肺气肿肺实质比例的ID偏度-PerfDef-Emphysema-Index（δ-index）。研究结果：PH患者显示出显著更大的不良灌注肺区范围以及更加强烈、更均匀的灌注缺陷。在3组和4组患者中，ID偏度揭示了在灌注缺陷中的ID分布比其他所有亚组更为均匀。δ-index能够进一步对3组和4组亚组进行细分（p < 0.001），以高准确度识别慢性血栓栓塞性PH（CTEPH，亚组4）患者（AUC：0.92，95%-CI，0.85–0.99）。研究结论：通过半自动的基于SDCT的肺灌注图可以检测并量化PH中的异常肺灌注。不良灌注肺区的ID偏度和δ-index可实现对PH亚组的分类，以高准确度识别3组和4组患者，且不受阅片者专业水平的影响。