From the Department of Radiology, University Hospital Erlangen.
Institute of Anatomy, Chair II, Friedrich Alexander University Erlangen-Nuremberg, Erlangen, Germany.
Invest Radiol. 2022 Mar 1;57(3):148-156. doi: 10.1097/RLI.0000000000000822.
The purpose of this study was to evaluate the minimum diagnostic radiation dose level for the detection of high-resolution (HR) lung structures, pulmonary nodules (PNs), and infectious diseases (IDs).
A preclinical chest computed tomography (CT) trial was performed with a human cadaver without known lung disease with incremental radiation dose using tin filter-based spectral shaping protocols. A subset of protocols for full diagnostic evaluation of HR, PN, and ID structures was translated to clinical routine. Also, a minimum diagnostic radiation dose protocol was defined (MIN). These protocols were prospectively applied over 5 months in the clinical routine under consideration of the individual clinical indication. We compared radiation dose parameters, objective and subjective image quality (IQ).
The HR protocol was performed in 38 patients (43%), PN in 21 patients (24%), ID in 20 patients (23%), and MIN in 9 patients (10%). Radiation dose differed significantly among HR, PN, and ID (5.4, 1.2, and 0.6 mGy, respectively; P < 0.001). Differences between ID and MIN (0.2 mGy) were not significant (P = 0.262). Dose-normalized contrast-to-noise ratio was comparable among all groups (P = 0.087). Overall IQ was perfect for the HR protocol (median, 5.0) and decreased for PN (4.5), ID-CT (4.3), and MIN-CT (2.5). The delineation of disease-specific findings was high in all dedicated protocols (HR, 5.0; PN, 5.0; ID, 4.5). The MIN protocol had borderline IQ for PN and ID lesions but was insufficient for HR structures. The dose reductions were 78% (PN), 89% (ID), and 97% (MIN) compared with the HR protocols.
Personalized chest CT tailored to the clinical indications leads to substantial dose reduction without reducing interpretability. More than 50% of patients can benefit from such individual adaptation in a clinical routine setting. Personalized radiation dose adjustments with validated diagnostic IQ are especially preferable for evaluating ID and PN lesions.
本研究旨在评估高分辨率（HR）肺部结构、肺结节（PN）和传染病（IDs）检测的最低诊断辐射剂量水平。
使用基于锡滤器的光谱成形协议对无已知肺部疾病的人体尸体进行临床前胸部 CT 试验，逐步增加辐射剂量。将 HR、PN 和 ID 结构的全诊断评估子集的部分协议转化为临床常规。此外，还定义了最小诊断辐射剂量协议（MIN）。在考虑个体临床指征的情况下，这些协议在 5 个月内前瞻性地应用于临床常规。我们比较了辐射剂量参数、客观和主观图像质量（IQ）。
HR 方案在 38 名患者（43%）中进行，PN 在 21 名患者（24%）中进行，ID 在 20 名患者（23%）中进行，MIN 在 9 名患者（10%）中进行。HR、PN 和 ID 之间的辐射剂量差异显著（分别为 5.4、1.2 和 0.6 mGy；P < 0.001）。ID 和 MIN 之间的差异（0.2 mGy）无统计学意义（P = 0.262）。所有组之间的剂量归一化对比噪声比均无显著差异（P = 0.087）。HR 方案的整体 IQ 为完美（中位数为 5.0），PN 降低（4.5），ID-CT（4.3）和 MIN-CT（2.5）。所有专用协议中疾病特异性发现的描绘均很高（HR，5.0；PN，5.0；ID，4.5）。MIN 方案对 PN 和 ID 病变的 IQ 存在边缘性，但对 HR 结构不足。与 HR 方案相比，PN 降低 78%，ID 降低 89%，MIN 降低 97%。
针对临床指征的个性化胸部 CT 可显著降低剂量，而不降低可解释性。在临床常规环境中，超过 50%的患者可以从这种个体化适应中受益。具有验证诊断 IQ 的个性化辐射剂量调整尤其适用于评估 ID 和 PN 病变。
