MR imaging of pituitary adenomas

Forty five patients with pituitary adenoma were evaluated with MR imaging at 2.0 T. There were 10 microadenomas and 35 macroadenomas. In 30 case, the tumor was demonstrate as solid nature and cystic changes, and hemorrhage could be characterized in 15 cases. The signal intensity of the solid portion of the tumor mainly appeared as isointense with gray matter on T1 weighted images, and iso or slightly hyperintense on T2 weighted images. Fluid-fluid levels of different intensity were seen in 8 out of 11 cases of hemorrhagic lesion, and layering of hyperintense supernate and hyperintense precipitate was demonstrated in all cases on both T1 and T2 weighted images. Involvement of the parasellar structures by the tumor, particularly optic chasm and cavenous portion of internal carotid artery, was accurately depicted on coronal and sagittal T1 weighted images. This experience suggests the MRI could be done as a initial step of imaging modality in the evaluation of the clinically suspected pituitary adenomas and carotid angiography may be avoid in some cases