屏气 CT 衍生的 CT 通气成像与 Galligas PET 具有良好的区域性准确性。

CT ventilation imaging derived from breath hold CT exhibits good regional accuracy with Galligas PET.

机构信息

Radiation Physics Laboratory, Sydney Medical School, University of Sydney, Camperdown, Australia.

Radiation Physics Laboratory, Sydney Medical School, University of Sydney, Camperdown, Australia; Northern Sydney Cancer Centre, Royal North Shore Hospital, Australia.

出版信息

Radiother Oncol. 2018 May;127(2):267-273. doi: 10.1016/j.radonc.2017.12.010. Epub 2017 Dec 28.

DOI:10.1016/j.radonc.2017.12.010

PMID:29290405

Abstract

BACKGROUND AND PURPOSE

CT ventilation imaging (CTVI) derived from four dimensional CT (4DCT) has shown only moderate spatial accuracy in humans due to 4DCT image artefacts. Here we assess the accuracy of an improved CTVI using high quality exhale/inhale breath-hold CT (BHCT).

MATERIALS AND METHODS

Eighteen lung cancer patients underwent exhale/inhale BHCT, 4DCT and Galligas PET ventilation scans in a single imaging session. For each BHCT and 4DCT scan, we performed deformable image registration (DIR) between the inhale and exhale phase images to quantify ventilation using three published metrics: (i) breathing induced lung density change, CTVI (ii) breathing induced volume change CTVI and (iii) the regional air-tissue product, CTVI Spatial accuracy was reported as the voxel-wise Spearman correlation r between CTVI and Galligas PET.

RESULTS

For BHCT-based CTVIs (N = 16), the CTVI, CTVI and CTVI methods yielded mean (range) r values of 0.67 (0.52-0.87), 0.57 (0.18-0.77) and 0.49 (0.14-0.75) respectively. By comparison the 4DCT-based CTVIs (n = 14) had values of 0.32 (-0.04 to 0.51), 0.16 (-0.31 to 44) and 0.49 (0.20-0.77) respectively.

CONCLUSIONS

High quality CT imaging is a key requirement for accurate CT ventilation imaging. The use of exhale/inhale BHCT can improve the accuracy of CTVI for human subjects.

摘要

背景与目的

由于 4DCT 图像伪影，来自四维 CT（4DCT）的 CT 通气成像（CTVI）在人体中仅显示出中等的空间准确性。在这里，我们评估了使用高质量呼气/吸气屏气 CT（BHCT）的改进 CTVI 的准确性。

材料与方法

18 例肺癌患者在单次成像过程中接受呼气/吸气 BHCT、4DCT 和 Galligas PET 通气扫描。对于每一次 BHCT 和 4DCT 扫描，我们在吸气和呼气阶段图像之间进行可变形图像配准（DIR），以使用三种已发表的指标量化通气：（i）呼吸引起的肺密度变化，CTVI（ii）呼吸引起的体积变化 CTVI 和（iii）区域空气-组织乘积，CTVI 空间准确性以 CTVI 和 Galligas PET 之间的体素-wise Spearman 相关 r 表示。

结果

对于基于 BHCT 的 CTVIs（N=16），CTVI、CTVI 和 CTVI 方法分别产生了 0.67（0.52-0.87）、0.57（0.18-0.77）和 0.49（0.14-0.75）的均值（范围）r 值。相比之下，基于 4DCT 的 CTVIs（n=14）的值分别为 0.32（-0.04 至 0.51）、0.16（-0.31 至 0.44）和 0.49（0.20 至 0.77）。