Wu Hai-Bo, Yuan Hui-Shu, Ma Furong, Zhao Qiang
Department of Radiology, Peking University Third Hospital.
Department of Radiology, Peking University Third Hospital.
Clin Imaging. 2017 Sep-Oct;45:30-33. doi: 10.1016/j.clinimag.2016.09.001. Epub 2016 Oct 4.
The study compared the use of periodically rotated overlapping parallel lines with enhanced reconstruction (PROPELLER) technique fast spin echo (FSE) T2 W and the sequence of three-dimensional fast imaging employing steady-state acquisition (3D-FIESTA) technique in the MRI of the internal auditory canal for overall image quality improvement.
One hundred thirty-two patients undergoing FSE T2 W PROPELLER and 3D-FIESTA examinations of the internal auditory canal were included. All examinations were performed at 3.0 T with comparison of a sagittal oblique FSE T2 W sequence with the PROPELLER technique to 3D-FIESTA in the same reconstructed orientation with PROPELLER. Image quality was evaluated by two radiologists using a 4-point scale. The Wilcoxon signed rank test was used to compare the data of the two techniques.
The image quality of FSE T2 W PROPELLER was significantly improved compared to the reconstructed images of 3D-FIESTA. Observer 1: median FSE T2 W with PROPELLER, 4 [mean, 3.455] versus median reconstructed 3D-FIESTA, 3 [mean, 3.15], (P<.001); Observer 2: median FSE T2 W with PROPELLER, 4 [mean, 3.47] versus median reconstructed 3D-FIESTA, 3 [mean, 3.25], (P<.001). Interobserver agreement was good (k value, 0.73) for the rating of the overall image quality.
The FSE T2 W PROPELLER technique for MRI of internal auditory canal reduced uncertainty caused by motion artifact and improved the quality of the image compared to the reconstructed 3D-FIESTA. It was affected by different parameters including the blade width, echo train length (ETL). This is explained by data oversampling at the center region of k-space, which requires additional imaging time over conventional MRI techniques. Increasing blade was expected to improve motion correction effects but also the signal-to-noise ratio. ETL increases the image sharpness and the overall image quality.
本研究比较了采用周期性旋转重叠平行线与增强重建（PROPELLER）技术的快速自旋回波（FSE）T2加权成像和采用稳态采集的三维快速成像（3D-FIESTA）技术在磁共振成像（MRI）内耳道检查中的应用，以全面提高图像质量。
纳入132例行内耳道FSE T2加权PROPELLER和3D-FIESTA检查的患者。所有检查均在3.0 T下进行，将矢状斜位FSE T2加权PROPELLER序列与相同PROPELLER重建方向的3D-FIESTA进行比较。由两名放射科医生使用4分制对图像质量进行评估。采用Wilcoxon符号秩检验比较两种技术的数据。
与3D-FIESTA重建图像相比，FSE T2加权PROPELLER的图像质量有显著提高。观察者1：FSE T2加权PROPELLER的中位数为4[均值，3.455]，而3D-FIESTA重建的中位数为3[均值，3.15]，（P<0.001）；观察者2：FSE T2加权PROPELLER的中位数为4[均值，3.47]，而3D-FIESTA重建的中位数为3[均值，3.25]，（P<0.001）。观察者间对整体图像质量评分的一致性良好（k值，0.73）。
与重建的3D-FIESTA相比，用于内耳道MRI的FSE T2加权PROPELLER技术减少了运动伪影导致的不确定性，提高了图像质量。它受不同参数影响，包括叶片宽度、回波链长度（ETL）。这是由k空间中心区域的数据过采样解释的，这比传统MRI技术需要额外的成像时间。增加叶片有望改善运动校正效果，但也会提高信噪比。ETL增加了图像清晰度和整体图像质量。
