前列腺的扩散加权成像：读出分段与选择性激发加速采集的图像质量和几何畸变

Diffusion-Weighted Imaging of the Prostate: Image Quality and Geometric Distortion of Readout-Segmented Versus Selective-Excitation Accelerated Acquisitions.

作者信息

Barth Borna K, Cornelius Alexander, Nanz Daniel, Eberli Daniel, Donati Olivio F

机构信息

From the *Institute of Diagnostic and Interventional Radiology, University Hospital Zürich, Zurich; †Department for Radiology, Cantonal Hospital Aarau, Aarau; and ‡Department of Urology, University Hospital Zürich, Zurich, Switzerland.

出版信息

Invest Radiol. 2015 Nov;50(11):785-91. doi: 10.1097/RLI.0000000000000184.

DOI:10.1097/RLI.0000000000000184

PMID:26146870

Abstract

OBJECTIVE

To compare image quality and geometric distortion between readout-segmented diffusion-weighted imaging (rs-DWI) and selective-excitation accelerated reduced-field of view (FOV) DWI (sTX-DWI) of the prostate.

MATERIALS AND METHODS

Sixty-five patients underwent 3-T MRI of the prostate including rs-DWI and sTX-DWI (b values, 0, 50, and 1000 seconds/mm²; FOV, 150 × 150 mm² and 77 ×150 mm for rs-DWI and sTX-DWI; slice thickness, 3 mm; acquisition time, 8:18 min and 1:37 min for rs-DWI and sTX-DWI). Two readers evaluated aspects of image quality and geometric distortion on a 5-point Likert scale. Quantitative analysis of geometric distortion was assessed by measurements of anteroposterior and left-right diameters and compared to T2-weighted turbo-spin echo sequence using intraclass correlation coefficient (ICC).

RESULTS

There was no significant difference in resolution, capsule demarcation, and zonal anatomy (P = 0.111-0.866). Overall image quality was rated "above average" by reader 1 (4.09 ± 0.66 and 4.03 ± 0.79; P = 0.433) and reader 2 (3.86 ± 0.66 and 3.80 ± 0.74; P = 0.465) for rs-DWI and sTX-DWI. Reader 1 (0.74 ± 0.67 and 1.17 ± 0.84; P < 0.001) and reader 2 (0.55 ± 0.64 and 1.09 ± 0.95; P < 0.001) rated the level of geometric distortion significantly lower for rs-DWI than sTX-DWI. Readout-segmented DWI (0.9 ± 2.2 mm) and sTX-DWI (2.1 ± 3.8 mm) overestimated the anteroposterior diameter of the prostate compared to T2-weighted turbo-spin echo sequence (P < 0.001), the difference being more pronounced for sTX-DWI [ICC, 0.89 (95% confidence interval, 0.83-0.93)] compared to rs-DWI [ICC, 0.96 (95% confidence interval, 0.94-0.96)].

CONCLUSION

Selective-excitation accelerated reduced-FOV DW images (sTX-DWI) of the prostate can be acquired more than 5 times faster than rs-DWI with comparable image quality, at the expense of significantly increased geometric distortion.

摘要

目的

比较前列腺读出分段扩散加权成像（rs-DWI）与选择性激发加速缩小视野（FOV）扩散加权成像（sTX-DWI）的图像质量和几何变形情况。

材料与方法

65例患者接受了3-T前列腺MRI检查，包括rs-DWI和sTX-DWI（b值为0、50和1000秒/平方毫米；rs-DWI和sTX-DWI的视野分别为150×150平方毫米和77×150毫米；层厚3毫米；rs-DWI和sTX-DWI的采集时间分别为8:18分钟和1:37分钟）。两名阅片者采用5分李克特量表对图像质量和几何变形的各个方面进行评估。通过测量前后径和左右径对几何变形进行定量分析，并使用组内相关系数（ICC）与T2加权快速自旋回波序列进行比较。

结果

在分辨率、包膜分界和分区解剖方面无显著差异（P = 0.-0.）。阅片者1（4.09±0.66和4.03±0.79；P = 0.433）和阅片者2（3.86±0.66和3.80±0.74；P = 0.465）对rs-DWI和sTX-DWI的整体图像质量评价为“高于平均水平”。阅片者1（0.74±0.67和1.17±0.84；P < 0.001）和阅片者2（0.55±0.64和1.09±0.95；P < 0.001）对rs-DWI几何变形程度的评分显著低于sTX-DWI。与T2加权快速自旋回波序列相比，读出分段DWI（0.9±2.2毫米）和sTX-DWI（2.1±3.8毫米）高估了前列腺的前后径（P < 0.001），与rs-DWI [ICC，0.96（95%置信区间，0.94-0.96）]相比，sTX-DWI [ICC，0.89（95%置信区间，0.83-0.93）]的差异更明显。