Gradient- and spin-echo T2-weighted imaging for SPIO-enhanced detection and characterization of focal liver lesions

✍ Scribed by Takeshi Yoshikawa; Donald G. Mitchell; Shozo Hirota; Yoshiharu Ohno; Kazushige Oda; Takaki Maeda; Masahiko Fujii; Kazuro Sugimura

• Publisher: John Wiley and Sons
• Year: 2006
• Tongue: English
• Weight: 309 KB
• Volume: 23
• Category: Article
• ISSN: 1053-1807
• DOI: 10.1002/jmri.20572

✦ Synopsis

Abstract

Purpose

To evaluate superparamagnetic iron oxide (SPIO)‐enhanced breathhold T2‐weighted GRASE imaging in detection and characterization of focal liver lesions.

Materials and Methods

In 30 patients (including 20 with cirrhosis) with 39 malignant and 25 benign lesions, gradient‐ and spin‐echo (GRASE) images with two echo times (75 and 90 msec; GRASE~75~ and GRASE~90~) were obtained prior to and following administration of SPIO, and compared with respiratory‐triggered and breathhold fast spin‐echo (RT‐FSE and BH‐FSE) images. Two readers evaluated image quality and reviewed 240 liver segments for sensitivity and specificity. Signal‐to‐noise ratio (SNR), and its reduction in liver and spleen after administration of SPIO, and lesion‐to‐liver contrast‐to‐noise ratio (CNR) were measured.

Results

Compared with RT‐FSE and BH‐FSE, GRASE reduced scan time by 77% to 82% and 21% to 27%, respectively. The image qualities with BH‐FSE and GRASE~75~ were higher than with BH‐FSE and GRASE~90~. BH‐FSE showed higher specificity than RT‐FSE and GRASE~90~, but otherwise there were no significant differences between pulse sequences for sensitivity or specificity. The mean SNR and CNR of the lesions with RT‐FSE were significantly higher than with the other methods. SPIO‐induced signal reduction of liver SNR was smallest with BH‐FSE.

Conclusion

GRASE is faster and more sensitive to SPIO than FSE, but its sensitivity and specificity were slightly inferior to those of BH‐FSE. Image quality is a current limitation. J. Magn. Reson. Imaging 2006. © 2006 Wiley‐Liss, Inc.