Nakamura Tatsuya, Naganawa Shinji, Koshikawa Tokiko, Fukatsu Hiroshi, Sakurai Yasuo, Aoki Ikuo, Ninomiya Ayako, Ishigaki Takeo
Department of Radiology, Nagoya University School of Medicine, Japan.
AJNR Am J Neuroradiol. 2002 Sep;23(8):1407-12.
Although the 12-minute 3D fast asymmetric spin-echo (FASE) protocol for imaging the inner ear has been satisfactory, reducing imaging time to minimize patient discomfort and maximize system throughput is desirable. We therefore evaluated the performance of a zero-fill interpolated (ZIP) fast recovery 3D FASE sequence in screening for cerebellopontine (CP) angle lesions in 90 seconds.
Thirty consecutive patients known or suspected to have CP angle lesions underwent MR imaging at 1.5 T with use of bilateral quadrature phased-array coils designed for examination of the CP angle. Conventional 3D FASE images (4000/240/1 [TR/TE/NEX]) were obtained in 11 minutes 48 seconds with a field of view (FOV) of 16 cm, matrix of 512 x 512 x 40, section thickness of 0.8 mm, and echo train length of 80. Then, ZIP fast recovery 3D FASE images (2000/240/1) were obtained in 90 seconds by using the same FOV. Contrast-enhanced T1-weighted 3D spoiled gradient-echo (SPGR) images were obtained as the reference standard. Three radiologists evaluated the images independently. Conventional 3D FASE and ZIP fast recovery 3D FASE images were reviewed at separate sessions.
On 3D SPGR images, 10 tumors were detected in 10 of the 30 patients. All lesions were depicted with both 3D FASE protocols. There were no false-positive results with either 3D FASE protocol. Both protocols showed 100% sensitivity and 100% specificity for all three reviewers.
High-spatial-resolution MR cisternography with the ZIP fast recovery 3D FASE protocol in 90 seconds results in a substantial reduction (by a factor of about eight) in the time required for screening for CP angle lesions compared with the previously reported conventional 3D FASE protocol, while maintaining high sensitivity and specificity.
尽管用于内耳成像的12分钟三维快速不对称自旋回波（FASE）协议已令人满意，但减少成像时间以最大程度减少患者不适并提高系统通量仍是可取的。因此，我们评估了零填充插值（ZIP）快速恢复三维FASE序列在90秒内筛查桥小脑（CP）角病变的性能。
30例已知或疑似患有CP角病变的连续患者在1.5T下进行磁共振成像，使用专为CP角检查设计的双侧正交相控阵线圈。常规三维FASE图像（4000/240/1[TR/TE/NEX]）在11分48秒内获得，视野（FOV）为16cm，矩阵为512×512×40，层厚为0.8mm，回波链长度为80。然后，通过使用相同的FOV在90秒内获得ZIP快速恢复三维FASE图像（2000/240/1）。对比增强T1加权三维扰相梯度回波（SPGR）图像作为参考标准。三位放射科医生独立评估图像。常规三维FASE和ZIP快速恢复三维FASE图像在不同的时间段进行回顾。
在三维SPGR图像上，30例患者中有10例检测到肿瘤。两种三维FASE协议均显示出所有病变。两种协议对所有三位评估者均显示出100%的敏感性和100%的特异性。
与先前报道的常规三维FASE协议相比，采用ZIP快速恢复三维FASE协议进行的高空间分辨率磁共振脑池造影在90秒内可将筛查CP角病变所需的时间大幅减少（约为八分之一），同时保持高敏感性和特异性。
