Erlemann R, Vassallo P, Bongartz G, Müller-Miny H, Rummeny E, Stöber U, Peters P E
Department of Clinical Radiology, Westfälische Wilhelms-Universität, Münster, Federal Republic of Germany.
Radiology. 1990 Aug;176(2):489-95. doi: 10.1148/radiology.176.2.2367666.
In 121 patients, image contrast and contrast-to-noise ratios (C/Ns) obtained with gadolinium diethylene-triaminepentaacetic acid (DTPA)-enhanced and nonenhanced fast low-angle shot (FLASH) sequences were compared with those achieved with spin-echo (SE) sequences. Among FLASH sequences, contrast between neoplasms and muscle was sufficient with a flip angle of 90 degrees following administration of Gd-DTPA but was 61% lower than that with the T2-weighted SE sequence. High contrast levels were obtained between tumors and bone marrow or fat in sclerotic, calcified, and fibrotic lesions with the use of a flip angle of 90 degrees and in lytic lesions with a flip angle of 10 degrees, reaching 66% of the contrast level obtained with the T1-weighted SE sequence. C/N between tumor and surrounding tissue was always significantly lower with FLASH sequences than with the ideal SE sequences usually used for tumor delineation. Thus, a replacement of the T2-weighted SE sequences by FLASH sequences cannot be recommended. A replacement of the T1-weighted SE sequences by FLASH sequences seems possible but does not significantly reduce examination time.
在121例患者中，将钆二乙三胺五乙酸（DTPA）增强和未增强的快速低角度激发（FLASH）序列获得的图像对比度和对比噪声比（C/N）与自旋回波（SE）序列获得的进行比较。在FLASH序列中，给予钆喷酸葡胺后，90度翻转角时肿瘤与肌肉之间的对比度足够，但比T2加权SE序列低61%。使用90度翻转角时，在硬化、钙化和纤维化病变中肿瘤与骨髓或脂肪之间获得高对比度，在溶骨性病变中使用10度翻转角时也获得高对比度，达到T1加权SE序列获得的对比度水平的66%。FLASH序列的肿瘤与周围组织之间的C/N始终显著低于通常用于肿瘤勾画的理想SE序列。因此，不建议用FLASH序列替代T2加权SE序列。用FLASH序列替代T1加权SE序列似乎可行，但不会显著缩短检查时间。
