Zaporozhan Julia, Ley Sebastian, Weinheimer Oliver, Eberhardt Ralf, Tsakiris Ioannis, Noshi Yasuhiro, Herth Felix, Kauczor Hans-Ulrich
Department of Radiology (E 010), German Cancer Research Center, and Department of Pediatric Radiology, Ruprecht-Karls-University, Heidelberg, Germany.
J Comput Assist Tomogr. 2006 May-Jun;30(3):460-8. doi: 10.1097/00004728-200605000-00018.
Quantitative evaluation of the lung parenchyma might be impaired or unreliable by use of reduced-dose CT protocols. Aim of the study was to define the threshold where reduced dose has significant impact on quantitative emphysema parameters.
Thirty patients with severe centrilobular emphysema underwent multidetector computed tomography (120 kV, 150 mAs). Original CT raw data were simulated using 10 mAs settings (10-100 SIMmAs). Quantitative analysis provided lung volume, emphysema volume, emphysema index, mean lung density, and 4 emphysema volume classes. Simulated low-dose results were compared with original acquisition.
Emphysema index showed no clinical relevant variation down to 30 SIMmAs. The large emphysema volume class was significantly different below 50 SIMmAs. The intermediate and small classes showed an overproportional variation below 50 SIMmAs.
Dose reduction down to 30 SIMmAs is possible for clinical routine. Settings below 50 SIMmAs significantly alter the in-detailed 3-dimensional emphysema quantification.
使用低剂量CT方案可能会损害或使肺实质的定量评估不可靠。本研究的目的是确定低剂量对定量肺气肿参数产生显著影响的阈值。
30例严重小叶中心型肺气肿患者接受了多排螺旋计算机断层扫描（120 kV，150 mAs）。使用10 mAs设置（10 - 100 SIMmAs）模拟原始CT原始数据。定量分析提供了肺容积、肺气肿容积、肺气肿指数、平均肺密度和4个肺气肿容积类别。将模拟的低剂量结果与原始采集结果进行比较。
肺气肿指数在低至30 SIMmAs时未显示出临床相关变化。在低于50 SIMmAs时，大肺气肿容积类别有显著差异。中、小类别在低于50 SIMmAs时显示出不成比例的变化。
低至30 SIMmAs的剂量降低可用于临床常规。低于50 SIMmAs的设置会显著改变肺气肿的三维详细定量。
