[Gd-DTPA in the MR diagnosis of pituitary adenomas]

25 patients with surgically (n = 14) and/or biochemically (n = 20) confirmed pituitary adenomas were examined on a 1.5 T superconducting MR system by means of multislice spin-echo technique, 3 mm thick sections and a 256 x 256 matrix. T1-weighted sagittal and coronal sections were obtained before and after administration of Gd-DTPA (0.1 mmol./kg. BW). 13 microadenomas and 12 macroadenomas were found. In unenhanced T1-weighted images 48% of the adenomas were isointense, 48% were hypointense and 4% were hyperintense. 58% of the adenomas enhanced to a lesser degree, 15% enhanced to a higher degree than the normal pituitary gland. 12% showed equal enhancement and 15% showed hypointense and hyperintense areas simultaneously. In 3 patients (12%) there was evidence of adenoma only in the enhanced images. The delineation of the adenoma from the cavernous sinus was possible in 95% of the enhanced, but only in 25% of the native scans.