Diagnosis of pulmonary artery sarcoma and differential diagnosis of pulmonary embolism with double-detector spectral CT: a case report / 中国医师杂志

Objective:The differential diagnosis of pulmonary artery sarcoma (PAS) and pulmonary embolism (PE) by double-detector spectral computerized tomography (CT) provides a new way to improve the detection rate of PAS and reduce the misdiagnosis rate.Methods:In the way of retrospective study, the Philips Nebula Workstation (ISP) was used to reconstruct electron density map, iodine density map and spectral curve in the spectral CT plain scan and enhancement of the PAS patient. In the plain scan image, the low density areas of the ascending aorta and the right pulmonary trunk were selected to measure their electronic density values. In the chest enhancement image, the iodine density of PAS area and PE area were measured respectively, and the spectral curves of PSA area and PE area were compared.Results:The electron density of the ascending aorta and the right pulmonary trunk in the low density area of the PAS patient during the plain scan of spectral CT were 104.4% EDW (relative to the percentage of the electron density of water) and 102.2% EDW, respectively, which were lower than those in the normal ascending aorta area. The fusion image of mixed energy and electron density clearly reflected the scope of the lesion. The iodine density in PAS area was 1.89 mg/ml, and the iodine density in PE area was 0.03 mg/ml during the enhancement phase. The iodine uptake in PAS area was significantly higher than that in PE area. The slope of PAS region was 2.08, and the slope of PE region was -1.86. The slopes of the two spectral curves were inconsistent.Conclusions:The electronic density, iodine density and spectral curve measured by double-detector spectral CT may provide powerful imaging basis for the diagnosis of PAS and the differentiation of PAS from PE, which is helpful for the early diagnosis of the lesions, and also provide basis for the biopsy location of the mixed lesions of PAS and PE.

Role of Dual-layer Detector Energy Spectral CT in Resting Myocardial Perfusion Imaging for Patients with Normal Coronary Artery / 中国医学科学院学报

Objective To investigate the role of dual-layer detector energy spectral CT in resting myocardial perfusion imaging for patients with normal coronary artery. Methods One hundred and fifty-six patients with suspected coronary heart disease underwent dual-layer detector energy spectral CT coronary angiography,and resting myocardial perfusion imaging was performed for 28 patients with normal coronary artery.According to American Heart Association's 17-segmentmodel,the iodine density and effective atomic number(Z

The application value of dual-layer detector spectral CT angiography in evaluation of brain perfusion in patients with acute ischemic stroke / 中华放射学杂志

Objective:To explore the clinical application value of the dual-layer detector spectral CTA in evaluation of brain perfusion impairment in patients with acute ischemic stroke.Methods:Clinical and imaging data of 35 patients with acute ischemic stroke in Weihai Central Hospital from March 2020 to October 2020 were reviewed retrospectively. All patients underwent head and neck spectral CTA examination and dynamic cerebral perfusion CT examination with dual-layer detector spectral CT. The iodine density map and effective atomic number map were reconstructed using CTA data, and the iodine density and effective atomic number, as well as the cerebral blood volume (CBV) and cerebral blood flow (CBF) values of the hypoperfusion area and the contralateral side were measured and compared; the areas of brain hypoperfusion regions were measured. Pearson′s correlation coefficient was used to analyze the correlation between iodine density values and CBV values, iodine density values and CBF values, effective atomic number values and CBV values, effective atomic number values and CBF values, as well as hypoperfusion area shown on CTA images and displayed on CTP-CBF map.Results:Of all the 35 patients, the iodine density value [(0.22±0.07) mg/ml], effective atomic number value (7.38±0.05), CBV value [(1.9±0.7) ml/100 g] and CBF value [(15.1±5.9) ml/(100 g·min)] of the hypoperfusion area were significantly lower than those of the healthy side [iodine density value (0.44±0.10) mg/ml, effective atomic number value (7.52±0.06), CBV value (3.4±0.7) ml/100 g, CBF value (57±27) ml/(100 g·min); t values were -14.7, -14.5, -11.2, -9.7, respectively, all P<0.001]. No significant difference was found between the hypoperfusion area shown on spectral CTA [(2 292±1 393) mm 2] and shown on CTP-CBF map [(2 290±1 359) mm 2] ( t=-0.076, P=0.944). There was a positive correlation between iodine density value and CBV (affected side: r=0.350, P=0.039, healthy side: r=0.551, P=0.001); a positive correlation was also found between effective atomic number value and CBV (affected side: r=0.488, P=0.003, healthy side: r=0.552, P=0.001); and there was a strong positive correlation between the hypoperfusion area on CTA and that on CTP-CBF ( r=0.993, P<0.001). Conclusion:Dual-layer detector spectral CTA can provide the “one-stop” assessement including head and neck vascular evaluation, as well as the hypoperfution area measument, which can be an alternative rapid method for evaluation of patients with acute ischemic stroke.