Gadolinium DTPA enhanced MR imaging of ACTH-secreting microadenomas of the pituitary gland.
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.
Doppman
J L
JL
Diagnostic Radiology Department, National Institutes of Health, Bethesda, MD 20892.
Frank
J A
JA
Dwyer
A J
AJ
Oldfield
E H
EH
Miller
D L
DL
Nieman
L K
LK
Chrousos
G P
GP
Cutler
G B
GB
Loriaux
D L
DL
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
D003287:Contrast Media; D009942:Organometallic Compounds; D004369:Pentetic Acid; D019786:Gadolinium DTPA