Kim T K, Lee H J, Jang H J, Kim A Y, Han J K, Choi B I
Department of Radiology, Seoul National University College of Medicine, University Hospital, Korea.
J Magn Reson Imaging. 1998 Nov-Dec;8(6):1213-8. doi: 10.1002/jmri.1880080606.
To compare the clinical usefulness of T2-weighted breath-hold sequences for imaging the liver, 33 patients with 97 focal hepatic lesions were studied with a 1.0-T scanner by using T2-weighted breath-hold turbo spin-echo (SE) sequences and T2-weighted breath-hold half-Fourier single-shot turbo SE (HASTE) sequences with and without fat suppression. Images were quantitatively analyzed for liver signal-to-noise ratio (SNR) and lesion-to-liver contrast-to-noise ratios (CNR). Qualitative analysis was performed for lesion conspicuity, motion artifacts, and anatomic sharpness of extrahepatic structures. Breath-hold turbo SE imaging with fat suppression showed the highest CNR for cystic lesions and the best lesion conspicuity for cystic and solid lesions among the four sequences. For solid lesions, there was no significant difference of lesion-to-liver CNR between them. HASTE sequence was superior to turbo SE sequences in terms of motion artifacts; however, the usefulness for evaluating focal hepatic lesions was limited compared with turbo SE sequence with fat suppression. Addition of fat suppression was not helpful for HASTE imaging because of decreased lesion conspicuity and extrahepatic details without the advantage of reducing motion artifacts. This study suggests that turbo SE sequence with fat suppression is most useful for breath-hold T2-weighted liver imaging at 1.0 T. Addition of imaging without fat suppression can be considered for evaluating extrahepatic structures. HASTE sequence may have a role for imaging uncooperative patients due to absence of motion artifacts.
为比较T2加权屏气序列对肝脏成像的临床实用性，我们使用1.0-T扫描仪，对33例患有97个肝脏局灶性病变的患者，采用有或没有脂肪抑制的T2加权屏气快速自旋回波（SE）序列和T2加权屏气半傅里叶单次激发快速SE（HASTE）序列进行了研究。对图像进行肝脏信噪比（SNR）及病变与肝脏对比噪声比（CNR）的定量分析。对病变的清晰度、运动伪影及肝外结构的解剖锐度进行定性分析。在这四种序列中，脂肪抑制的屏气快速SE成像对囊性病变显示出最高的CNR，对囊性和实性病变显示出最佳的病变清晰度。对于实性病变，它们之间的病变与肝脏CNR没有显著差异。在运动伪影方面，HASTE序列优于快速SE序列；然而，与有脂肪抑制的快速SE序列相比，其对评估肝脏局灶性病变的实用性有限。由于病变清晰度和肝外细节减少且没有减少运动伪影的优势，脂肪抑制对HASTE成像没有帮助。本研究表明，有脂肪抑制的快速SE序列对1.0 T的屏气T2加权肝脏成像最有用。对于评估肝外结构，可考虑增加无脂肪抑制的成像。由于没有运动伪影，HASTE序列可能对不配合的患者成像有作用。
