MR imaging in infra-, para- and retrosellar mass lesions.

To determine its diagnostic efficacy in infra-, para- and retrosellar mass lesions magnetic resonance (MR) imaging was compared with computed tomography (CT) in 39 cases. Thirty-six lesions were imaged with a Siemens 0.5 T superconducting unit, three with a 1.5 T unit. CT scanning was performed with third generation equipment. There were 28 neoplasms including eight pituitary adenomas with infrasellar extension, four meningiomas, four extensions from regional malignancies, three chordomas, three juvenile angiofibromas, three medial temporal gliomas, and one each of neuroma, epidermoid and metastasis. Eleven non-neoplastic masses included four vascular anomalies, three cholesterol granulomas, two arachnoid cysts, one sphenoid mucocele and one mixed sclerosing bone dystrophy with mass-like thickening of basisphenoid and basiocciput. While MR and CT were equally sensitive (100%), MR was superior in further delineating and characterizing a lesion. MR showed normal or abnormal blood vessels better than CT, and revealed changes of compact bone often quite satisfactorily. Effects on the brain parenchyma or CSF and airspaces were consistently well demonstrated. Provided absence of contraindications MR should be the primary radiologic screening test in suspected mass lesions of above location.