Liver ; MR ; Magnetic Resonance(MR) ; pulse sequences ; Magnetic Resonance(MR) ; comparative studies
Abstract
Purpose : To document the relative usefulness of true Fast-imaging steady-state precession(FISP) comparing to breath-hold turbo spin-echo(TSE), and half-Fourier single-shot turbo spin-echo(HASTE) as a fast T2-weighted sequence during hepatic MR imaging.
Materials and Methods : For 46 patients with 87 focal hepatic lesions(hepatocellular carcinoma, n=26; metastasis. n=5; cavernous hemangioma, n=37; cyst, n=19), we obtained MR imaging of the liver at 1.5T. True FISP, TSE with and without fat-suppresion(FS), and HASTE with and without FS images were obtained during one breath-hold. Images were compared on the basis of tumor detectability and lesion-to-liver contrast-to-noise ratio(CNR). Qualitative analysis of each imaging sequence was also performed in terms of hepatic contour, visibility of vascular landmarks and imaging artifacts.
Results : TSE-FS depicted more focal lesions(78/87, 90%) than other sequences(TSE, 75/87=86%;HASTE, 74/87=85%; HASTE-FS, 75/87=86%;true FISP,73/87=84%). However, there was no statistical significance between each sequence(p> .05). Using true FISP or HASTE, there was a statistically significant difference(p× .01) between the CNRs of solid tumors, crystal and hemangiomas. Additionally, true FISP sequence showed better hepatic contour, vascular landmarks and less artifacts comparing with TSE or HASTE regardless of FS(p< .001).
Conclusion : True FISP sequence allows differentiation between solid tumors, hemangiomas and cystic lesions in terms of CNR, and provides better imaging quality than other fast T2-weighted MR sequences.