title: T1 signal hyperintensity in the sellar region: spectrum of findings.
abstract: T1 signal hyperintensity is a common finding at magnetic resonance imaging of the sellar region. However, this signal intensity pattern has different sources, and its significance depends on the clinical context. Normal variations in sellar T1 signal hyperintensity are related to vasopressin storage in the neurohypophysis, the presence of bone marrow in normal and variant anatomic structures, hyperactive hormone secretion in the anterior pituitary lobe (eg, in newborns and pregnant or lactating women), and flow artifacts and magnetic susceptibility effects. Pathologic variations in T1 signal hyperintensity may be related to clotting of blood (in hemorrhagic pituitary adenoma, pituitary apoplexy, Sheehan syndrome, or thrombosed aneurysm) or the presence of a high concentration of protein (Rathke cleft cyst, craniopharyngioma, or mucocele), fat (lipoma, dermoid cyst, lipomatous meningioma), calcification (craniopharyngioma, chondroma, chordoma), or a paramagnetic substance (manganese, melanin). After treatment, T1 signal hyperintensity may result from the presence of materials used for surgical packing (gelatin sponge, fat); from compression of the cavernous sinus and reduction of the venous flow, caused by overpacking of the operative bed; or from hormone hypersecretion by a remnant of normal tissue in the anterior lobe of the pituitary gland.
authors.affiliation: Department of Neuroradiology, Pitié-Salpêtrière Hospital, 74 Boulevard de l'Hôpital, 75013 Paris, France. fabrice.bonneville@psl.ap-hop-paris.fr
authors.forename: Fabrice
authors.initials: F
authors.lastname: Bonneville
authors.forename: Françoise
authors.initials: F
authors.lastname: Cattin
authors.forename: Kathlyn
authors.initials: K
authors.lastname: Marsot-Dupuch
authors.forename: Didier
authors.initials: D
authors.lastname: Dormont
authors.forename: Jean-François
authors.initials: JF
authors.lastname: Bonneville
authors.forename: Jacques
authors.initials: J
authors.lastname: Chiras
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D005260:Female; D006801:Humans; D007231:Infant, Newborn; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D010900:Pituitary Diseases / Q000473:pathology*; D010902:Pituitary Gland / Q000033:anatomy & histology / Q000473:pathology*; D010911:Pituitary Neoplasms / Q000473:pathology*; D012658:Sella Turcica / Q000033:anatomy & histology / Q000473:pathology*