ACTH secreting pituitary microadenomas disclosed only by gadolinium DTPA enhanced MRI.
OBJECTIVE
To assess the usefulness of Gd-DTPA enhancement in disclosing microadenomas of the pituitary gland that had not been demonstrated by non enhanced MRI in patients with Cushing's disease.


METHODS
Six patients with Cushing's disease underwent pre and post enhancement MRI scanning and the findings were correlated at surgery and confirmed by histological and immunohistochemistry studies of the surgical specimen.


RESULTS
In all cases post enhancement MR scans demonstrated circumscribed hypointense foci that corresponded well with the location and extension of the adenomatous tissue found at surgery. Selective removal of the microadenomas failed to improve the clinical and laboratory abnormalities in two of the six patients. Such cases did not present residual hypointense foci in the post-operative Gd-DTPA enhanced MRI.


CONCLUSIONS
Results suggest that Gd-DTPA enhanced MRI is useful to detect pituitary microadenomas; however, the abnormalities of the pituitary tissue may extend beyond the abnormal imaging.
Hypothalamus-Hypophysis Clinic, Hospital General de México, D.F.
B
B
Boleaga
G
G
Fanghänel
L
L
Cortinas
E
E
Valdés
E
E
Vargas
F
F
Velasco
D000236:Adenoma / Q000150:complications / Q000175:diagnosis* / Q000378:metabolism / Q000601:surgery; D000293:Adolescent; D000324:Adrenocorticotropic Hormone / Q000378:metabolism*; D000328:Adult; D003287:Contrast Media; D003480:Cushing Syndrome / Q000097:blood / Q000209:etiology*; D005188:False Negative Reactions; D005260:Female; D005682:Gadolinium; D019786:Gadolinium DTPA; D006801:Humans; D006854:Hydrocortisone / Q000097:blood; D007016:Hypophysectomy; D008279:Magnetic Resonance Imaging; D008297:Male; D009942:Organometallic Compounds; D004369:Pentetic Acid; D010911:Pituitary Neoplasms / Q000150:complications / Q000175:diagnosis* / Q000378:metabolism / Q000601:surgery; D014057:Tomography, X-Ray Computed; D016896:Treatment Outcome
D003287:Contrast Media; D009942:Organometallic Compounds; D004369:Pentetic Acid; D000324:Adrenocorticotropic Hormone; D005682:Gadolinium; D019786:Gadolinium DTPA; D006854:Hydrocortisone