The value of non-contrast dual-layer spectral detector CT with multiple parameters in the diagnosis of acute pulmonary embolism
10.3760/cma.j.cn112149-20230409-00269
- VernacularTitle:双层探测器光谱CT平扫多参数诊断急性肺栓塞的价值
- Author:
Sidong XIE
1
;
Yuanyuan CHU
;
Yani DUAN
;
Yanqiu ZHU
;
Zhuang KANG
;
Jiansheng ZHANG
;
Jie QIN
Author Information
1. 中山大学附属第三医院放射科，广州510630
- Keywords:
Pulmonary embolism;
Tomography, X-ray computed;
Virtual monoenergetic image;
Electron density map
- From:
Chinese Journal of Radiology
2023;57(10):1080-1086
- CountryChina
- Language:Chinese
-
Abstract:
Objective:To explore the diagnostic value of virtual monoenergetic image (VMI) and electron density map (EDM) generated by non-contrast dual-layer spectral detector CT in acute pulmonary embolism(APE).Methods:The clinical and imaging data of 27 patients (41 lesions) who underwent CT pulmonary angiography (CTPA) using dual-layer spectral detector CT and were diagnosed with APE in the Third Affiliated Hospital of Sun Yat-sen University from October 2022 to May 2023 were retrospectively analyzed. All patients received a dual-layer spectral detector CT non-contrast scan. Based on the non-contrast scan data, conventional 120 kVp polyenergetic images (PI), virtual monoenergetic images (40, 70, 100 keV VMI), electron density maps (EDM), and effective atomic number maps (Z eff) were respectively reconstructed. Taking CTPA as the gold standard, the detection rate of APE in different reconstruction images of non-contrast scan were evaluated. The vascular lesion was used as the pulmonary embolism group and the corresponding position of the normal vessel at the same level of the diseased vessel as the control group, and the Wilcoxon rank-sum test was used to compare the differences of CT values on PI and 40, 70, and 100 keV VMI (CT PI, CT 40 keV, CT 70 keV, CT 100 keV) as well as the ED values on the EDM, and the Z eff value on the Z eff images between the 2 groups. Parameters with statistically significant differences were included in a multifactor logistic regression, resulting in the construction of a logistic regression model. Receiver operator characteristic curve and area under curve (AUC) were applied to evaluate the diagnostic efficiency of different spectral quantitative parameters and logistic regression model in identifying pulmonary embolism group from normal control group. Results:The detection rates of APE on PI, EDM, Z eff map, and EDM and Z eff map fusion images were 14.6% (6/41), 82.9% (34/41), 51.2% (21/41), and 97.6% (40/41), respectively. CT PI, ED, CT 40 keV, CT 70 keV and CT 100 keV in pulmonary embolism group were statistically higher than those in control group ( Z values were 1 009.00, 1 024.50, 1 038.00, 1 079.00 and 1 076.00, respectively, P<0.05). Finally, CT PI, CT 40 keV, and CT 100 keV were selected to construct the logistic regression model. The AUC, sensitivity, specificity, and accuracy of the logistic regression model for distinguishing the embolism group from the control group were 0.771, 0.769, 0.744, and 0.756, respectively. Conclusion:Non-contrast images of dual-layer spectral detector CT VMI and EDM have some clinical value in detecting and diagnosing APE.
