Fast and ultrafast magnetic resonance imaging in renal lesions

Our purpose was to analyze and compare the image quality and contrast-to-no ise ratio (CNR) of different fast T1- and T2-weighted sequences with conven tional spin-echo sequences in renal MRI. Twenty-three patients with focal r enal lesions were examined with a T2-weighted ultrafast turbo spin-echo (UT SE) sequence with and without frequency selective fat suppression (SPIR), a combined gradient-and-spin-echo sequence (GraSE), and a conventional spin- echo sequence (SE), In addition, T1-weighted images were obtained pre- and postcontrast, using a fast spin-echo sequence (TSE) with and without SPIR a nd the conventional SE sequence. Among the T2-weighted images, the highest CNR and the best image quality were obtained with the UTSE sequence, follow ed by the fat-suppressed UTSE sequence. GraSE and conventional SE sequences showed a significantly lower CNR and image quality (p < 0.05). The T1-weig hted sequences did not show significant differences, in either precontrast or postcontrast measurements, T2-weighted UTSE with and without fat suppres sion combined excellent image quality and high CNR for imaging and detectio n of renal lesions. The T1-weighted fast sequences provided no alternative to the gradient-echo or to the conventional SE sequences. The results of th is systematic study suggest the use of T2-weighted fast techniques for impr oved diagnostic accuracy of renal MRI.