Messerli Michael, Giannopoulos Andreas A, Leschka Sebastian, Warschkow René, Wildermuth Simon, Hechelhammer Lukas, Bauer Ralf W
1 Department of Nuclear Medicine, University Hospital Zurich, University Zurich , Zürich , Switzerland.
2 Division of Radiology and Nuclear Medicine, Cantonal Hospital St. Gallen , St. Gallen , Switzerland.
Br J Radiol. 2017 Dec;90(1080):20170469. doi: 10.1259/bjr.20170469. Epub 2017 Oct 3.
To determine the value of ultralow-dose chest CT for estimating the calcified atherosclerotic burden of the thoracic aorta using tin-filter CT and compare its diagnostic accuracy with chest direct radiography.
A total of 106 patients from a prospective, IRB-approved single-centre study were included and underwent standard dose chest CT (1.7 ± 0.7 mSv) by clinical indication followed by ultralow-dose CT with 100 kV and spectral shaping by a tin filter (0.13 ± 0.01 mSv) to achieve chest X-ray equivalent dose in the same session. Two independent radiologists reviewed the CT images, rated image quality and estimated presence and extent of calcification of aortic valve, ascending aorta and aortic arch. Conventional radiographs were also reviewed for presence of aortic calcifications.
The sensitivity of ultralow-dose CT for the detection of calcifications of the aortic valve, ascending aorta and aortic arch was 93.5, 96.2 and 96.2%, respectively, compared with standard dose CT. The sensitivity for the detection of thoracic aortic calcification was significantly lower on chest X-ray (52.3%) compared with ultralow-dose CT (p < 0.001).
A reliable estimation of calcified atherosclerotic burden of the thoracic aorta can be achieved with modern tin-filter CT at dose values comparable to chest direct radiography. Advances in knowledge: Our findings suggest that ultralow-dose CT is an excellent tool for assessing the calcified atherosclerotic burden of the thoracic aorta with higher diagnostic accuracy than conventional chest radiography and importantly without the additional cost of increased radiation dose.
使用锡滤过CT确定超低剂量胸部CT在评估胸主动脉钙化粥样硬化负荷中的价值，并将其诊断准确性与胸部直接X线摄影进行比较。
纳入了一项经机构审查委员会批准的前瞻性单中心研究中的106例患者，根据临床指征先进行标准剂量胸部CT（1.7±0.7 mSv），随后进行100 kV并采用锡滤过器进行光谱塑形的超低剂量CT（0.13±0.01 mSv），以在同一次检查中达到胸部X线等效剂量。两名独立的放射科医生对CT图像进行了评估，对图像质量进行了评分，并估计了主动脉瓣、升主动脉和主动脉弓钙化的存在情况和范围。还对传统X线片进行了主动脉钙化情况的评估。
与标准剂量CT相比，超低剂量CT检测主动脉瓣、升主动脉和主动脉弓钙化的敏感性分别为93.5%、96.2%和96.2%。与超低剂量CT相比，胸部X线检测胸主动脉钙化的敏感性显著较低（52.3%）（p<0.001）。
使用现代锡滤过CT能够可靠地估计胸主动脉钙化粥样硬化负荷，其剂量值与胸部直接X线摄影相当。知识进展：我们的研究结果表明，超低剂量CT是评估胸主动脉钙化粥样硬化负荷的一种优秀工具，其诊断准确性高于传统胸部X线摄影，重要的是无需承担额外的辐射剂量增加成本。
