3D gradient echo sequence provides better images in contrast-enhanced imaging of the pituitary gland at 3 T

摘要

With the increasing availability of 3 T MRI systems in the clinics, radiologists are getting acquainted with the different image sequences and its superiority over the images obtained by 1.5 T MRI. In comparison with 1.5 T MRI, 3 T MRI has prolonged T_1 values, a higher specific absorption rate, increased susceptibility artifacts and magnetic field inhomogeneity. Therefore, it is necessary to optimize organ-specific image acquisition parameters and sequences. It is common practice to acquire post-contrast thin-slice 2D spin echo (SE) T_1 -weighted images (T_1WI) for pituitary lesions. As mentioned by Kakite et al., owing to prolongation of T_1 values for 3 T systems, postcontrast 2D-SE T_1WI may not enable the correct demarcation or delineation of pituitary microadenoma from surrounding structures. Moreover, 3D gradient echo T_1 sequences will have susceptible artifacts and high signal intensity from flowing blood, which may also make image interpretation difficult.