Yonago Acta medica 1996;39:73–81
Evaluation of Fast Gradient System Breath-Hold FLASH Imaging in the Examination of Liver Tumors: Comparison with Conventional Spin-Echo Pulse Sequences
Kotaro Yoshida, Yuji Suto, Takashi Kato, Shuji Sugihara and Naoto Ohmura
Department of Radiology, Faculty of Medicine, Tottori University, Yonago 683, Japan
Forty one patients with various types of focal liver tumors were imaged with a multisection fast low-angle shot (FLASH) gradient echo sequence using a fast gradient MR system. We compared the T1-weighted images of the liver with the multisection FLASH and conventional spin-echo (SE) pulse sequences in order to determine whether FLASH images could replace SE images. The multisection FLASH sequence provided a significantly higher signal-to-noise ratio (SNR), liver-spleen contrast, liver-spleen contrast-to-noise ratio (CNR), liver-nodule CNR (P < 0.01) and liver-tumor contrast (P < 0.05) than did the T1-weighted SE sequence. The overall image quality of the multisection FLASH sequence was superior to that of the T1-weighted SE sequence (P < 0.05). The signal intensity features of liver tumors with both sequences were almost the same. There was a statistically mutual correlation in the signal intensity between hepatocellular carcinomas and metastases. The detectability of liver tumors in FLASH sequences was superior to that in SE sequences. These findings suggest that multisection FLASH sequence imaging can replace T1-weighted SE sequence imaging.
Key words: breath-hold FLASH; fast gradient; MRI; liver tumor
