Department of Radiology and Institute of Radiation Medicine, Seoul National University Hospital, 101 Daehak-ro, Jongo-gu, Seoul 03080, Korea.
Department of Pediatrics, Seoul National University Hospital, Seoul, Korea.
AJR Am J Roentgenol. 2020 Aug;215(2):488-493. doi: 10.2214/AJR.19.22269. Epub 2020 May 14.
The aim of this study was to develop a low-dose radiography protocol for the neonatal ICU (NICU) using a new mobile digital radiography system with advanced denoising image processing and to evaluate the noninferiority of that protocol. In this prospective randomized study, 40 neonates in the NICU underwent radiography of the thorax and abdomen with two different mobile radiography units: conventional technique on one unit (50 kV, 1.6 mAs, and no additional filtration) and a new technique on another unit (54 kV, 0.1-mm Cu filtration). Three low-dose protocols for the second unit were developed in a phantom study: protocol A (100% equivalent dose with conventional protocol), protocol B (80% equivalent dose), and protocol C (64% equivalent dose). The noninferiority of each low-dose protocol was assessed by three independent readers using image quality criteria. Forty patients each underwent three pairs of radiography examinations (protocol A and the conventional protocol, protocol B and the conventional protocol, and protocol C and the conventional protocol), except one pair that did not include one image of the conventional protocol. The interrater reliability among the three readers was 0.91 ( < 0.001). Both of the low-dose protocols (B and C) were statistically noninferior to the conventional protocol with respect to overall image quality. Protocol B better depicted almost all anatomic landmarks and had better overall image quality than the conventional protocol. Using appropriate technique and acquisition factors, radiation dose can be lowered on a digital radiography system without significant effect on the image quality by adding filtrations and a new denoising technique.
本研究旨在开发一种新的移动数字化放射系统,该系统具有先进的降噪图像处理功能,用于新生儿重症监护病房(NICU)的低剂量放射摄影,并评估该方案的非劣效性。在这项前瞻性随机研究中,NICU 中的 40 名新生儿接受了胸部和腹部的两种不同移动放射摄影系统的放射摄影检查:一台设备采用传统技术(50 kV、1.6 mAs,无额外滤过),另一台设备采用新的技术(54 kV、0.1-mm Cu 滤过)。在体模研究中,为第二台设备开发了三种低剂量方案:方案 A(与传统方案等效剂量的 100%)、方案 B(等效剂量的 80%)和方案 C(等效剂量的 64%)。通过三位独立读者使用图像质量标准评估每个低剂量方案的非劣效性。除一对不包括传统方案的图像外,每位患者各进行了三组放射摄影检查(方案 A 和传统方案、方案 B 和传统方案、方案 C 和传统方案)。三位读者之间的组内相关系数为 0.91(<0.001)。与传统方案相比,低剂量方案 B 和方案 C 在总体图像质量方面均具有统计学上的非劣效性。方案 B 能够更好地显示几乎所有的解剖标志,并且总体图像质量优于传统方案。通过适当的技术和采集因素,可以在数字化放射系统上降低辐射剂量,而不会对图像质量产生显著影响,通过添加滤过和新的降噪技术。