Computed axial tomography of pituitary adenomas.

Computed axial tomography is an excellent screening procedure in patients suspected of having a tumour in or near the sella turcica. Even microadenomas can sometimes be diagnosed, although not excluded, pluridirectional tomography remaining the most accurate method for their detection. Differentiation of adenomas from other parasellar tumours is not possible by computed tomography alone. An empty sella can be differentiated reliably from tumorous sellar enlargements although cystic adenomas can cause difficulties in differential diagnosis. The amount of anteroposterior and lateral extensions can be determined but the exact suprasellar extension cannot be estimated. Coronal sections of intrathecal enhancement with either conventional or computed tomography help in these cases. Carotid angiography is needed to differentiate vascular lesions from non-vascular ones.