title: Gadolinium DTPA enhanced MR imaging of ACTH-secreting microadenomas of the pituitary gland.
abstract: Gadolinium diethylenetriamine pentaacetic acid (DTPA) enhanced magnetic resonance imaging was performed in eight patients with Cushing disease and surgically proven pituitary microadenomas. A 1.5 T scanner was used with 3 mm contiguous slices. Short repetition times (TR), short echo times (TE), and long TR, long TE sequences were obtained before and serially after intravenous administration of Gd-DTPA. Three of eight (38%) microadenomas were undetectable both without and with Gd-DTPA: one post-Gd-DTPA scan was false positive on the side opposite the adenoma. Hemihypophysectomy based on a petrosal sinus adrenocorticotropic hormone (ACTH) gradient cured all three patients. Two microadenomas (25%) were visible as hypointense foci following Gd-DTPA but not on unenhanced scans. The remaining three microadenomas (38%) were seen before and after Gd-DTPA on T1-weighted images. In this small series of ACTH-producing microadenomas, one-third were seen on unenhanced 1.5 T scans, one-third were seen only after Gd-DTPA, and one-third were not imaged even with Gd-DTPA enhancement.
authors.affiliation: Diagnostic Radiology Department, National Institutes of Health, Bethesda, MD 20892.
authors.forename: J L
authors.initials: JL
authors.lastname: Doppman
authors.forename: J A
authors.initials: JA
authors.lastname: Frank
authors.forename: A J
authors.initials: AJ
authors.lastname: Dwyer
authors.forename: E H
authors.initials: EH
authors.lastname: Oldfield
authors.forename: D L
authors.initials: DL
authors.lastname: Miller
authors.forename: L K
authors.initials: LK
authors.lastname: Nieman
authors.forename: G P
authors.initials: GP
authors.lastname: Chrousos
authors.forename: G B
authors.initials: GB
authors.lastname: Cutler
authors.forename: D L
authors.initials: DL
authors.lastname: Loriaux
mesh_terms: D000236:Adenoma / Q000175:diagnosis*; D000328:Adult; D003287:Contrast Media; D005260:Female; D019786:Gadolinium DTPA; D006801:Humans; D007089:Image Enhancement / Q000379:methods*; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008875:Middle Aged; D009942:Organometallic Compounds; D004369:Pentetic Acid; D010911:Pituitary Neoplasms / Q000175:diagnosis*; D011237:Predictive Value of Tests
chemical_list: D003287:Contrast Media; D009942:Organometallic Compounds; D004369:Pentetic Acid; D019786:Gadolinium DTPA