DISPLACEMENT OF THE NORMAL PITUITARY-GLAND BY SELLAR AND JUXTASELLAR TUMORS - SURGICAL-MRI CORRELATION AND USE IN DIFFERENTIAL-DIAGNOSIS

We compared the position of the normal pituitary gland as estimated by gadolinium (Gd)-DTPA-enhanced MRI, with its position at surgery in 40 patients with intra- and juxtasellar tumours: 22 pituitary adenomas, 4 craniopharyngiomas, 7 meningiomas, 2 germinomas, and 5 Rathke cleft cysts. In 37 of these, the normal gland showed more intense contrast e nhancement than the adjacent tumour, from which it could be differenti ated by Gd-DTPA-enhanced MRI, especially in the sagittal plane. The di rection of displacement of the normal pituitary gland correlated well with tumour type, so that its position proved helpful in the different ial diagnosis. The normal gland was typically displaced superiorly by pituitary adenomas, inferiorly by craniopharyngiomas, and anteriorly b y germinomas. It showed variable displacement by Rathke cleft cysts, a nd was not usually displaced by meningiomas.