Amsterdam UMC, Radiology and Nuclear Medicine, University of Amsterdam, Room Z0-178, Meibergdreef 9, 1100 DD, Amsterdam, Netherlands.
Department of Radiation Oncology, Netherlands Cancer Institute, Amsterdam, Netherlands.
Eur Radiol Exp. 2020 Feb 7;4(1):9. doi: 10.1186/s41747-019-0138-x.
Diffusion-weighted imaging (DWI) has shown great value in rectal cancer imaging. However, traditional DWI with echo-planar imaging (DW-EPI) often suffers from geometrical distortions. We applied a three-dimensional diffusion-prepared stimulated-echo turbo spin-echo sequence (DPsti-TSE), allowing geometrically undistorted rectal DWI. We compared DPsti-TSE with DW-EPI for locally advanced rectal cancer DWI.
For 33 prior-to-treatment patients, DWI images of the rectum were acquired with DPsti-TSE and DW-EPI at 3 T using b-values of 200 and 1000 s/mm. Two radiologists conducted a blinded scoring of the images considering nine aspects of image quality and anatomical quality. Tumour apparent diffusion coefficient (ADC) and distortions were compared quantitatively.
DPsti-TSE scored significantly better than DW-EPI in rectum distortion (p = 0.005) and signal pileup (p = 0.001). DPsti-TSE had better tumour Dice similarity coefficient compared to DW-EPI (0.84 versus 0.80, p = 0.010). Tumour ADC values were higher for DPsti-TSE compared to DW-EPI (1.47 versus 0.86 × 10 mm/s, p < 0.001). Radiologists scored DPsti-TSE significantly lower than DW-EPI on aspects of overall image quality (p = 0.001), sharpness (p < 0.001), quality of fat suppression (p < 0.001), tumour visibility (p = 0.009), tumour conspicuity (p = 0.010) and rectum wall visibility (p = 0.005).
DPsti-TSE provided geometrically less distorted rectal cancer diffusion-weighted images. However, the image quality of DW-EPI over DPsti-TSE was referred on the basis of several image quality criteria. A significant bias in tumour ADC values from DPsti-TSE was present. Further improvements of DPsti-TSE are needed until it can replace DW-EPI.
弥散加权成像（DWI）在直肠癌成像中具有重要价值。然而，传统的平面回波成像（DW-EPI）弥散加权成像常受到几何变形的影响。我们应用三维弥散准备激发回波平面成像（DPsti-TSE），允许直肠 DWI 无几何失真。我们比较 DPsti-TSE 与 DW-EPI 用于局部进展期直肠癌 DWI。
对 33 例治疗前患者，在 3T 上使用 200 和 1000 s/mm 的 b 值，分别采用 DPsti-TSE 和 DW-EPI 采集直肠 DWI 图像。两名放射科医生对图像的九个方面进行了盲法评分，包括图像质量和解剖质量。比较了肿瘤表观扩散系数（ADC）和失真的定量差异。
DPsti-TSE 在直肠扭曲（p = 0.005）和信号堆积（p = 0.001）方面的评分明显优于 DW-EPI。DPsti-TSE 的肿瘤 Dice 相似系数优于 DW-EPI（0.84 对 0.80，p = 0.010）。与 DW-EPI 相比，DPsti-TSE 的肿瘤 ADC 值较高（1.47 对 0.86×10mm/s，p<0.001）。放射科医生在整体图像质量（p = 0.001）、锐度（p<0.001）、脂肪抑制质量（p<0.001）、肿瘤可见度（p = 0.009）、肿瘤显著性（p = 0.010）和直肠壁可见度（p = 0.005）等方面的评分明显低于 DW-EPI。
DPsti-TSE 提供了几何失真较小的直肠癌弥散加权图像。然而，基于一些图像质量标准，DW-EPI 的图像质量优于 DPsti-TSE。DPsti-TSE 存在肿瘤 ADC 值的显著偏差。DPsti-TSE 需要进一步改进，直到它可以取代 DW-EPI。
