title: Magnetic resonance imaging characteristics and surgical results of adrenocorticotropin-secreting pituitary adenomas.
abstract: OBJECTIVE
  To evaluate magnetic resonance imaging (MRI) characteristics and surgical results of adrenocorticotropin (ACTH)-secreting pituitary adenomas.
  
  
  METHODS
  MRI characteristics and relationship between MRI positive rate and surgical results of 266 patients with pathologically confirmed Cushing's disease were analyzed retrospectively. All patients underwent thin-section sagittal and coronal scans of the pituitary gland before and after administration of gadolinium-diethylene triamine pentaacetic acid (Gd-DTPA) on a 1.5 Tesla MRI scanner, and dynamic enhanced MRI was performed in 39 patients. All patients underwent transsphenoidal adenomectomy. Endocrinological examinations and assessments were performed.
  
  
  RESULTS
  Preoperative MRI revealed normal results in 41 (15.4%) cases, microadenoma in 179 (67.3%), macroadenoma in 42 (15.8%), and huge adenoma in 4 (1.5%). Pituitary apoplexy was found in 13 (4.9%) cases. Positive rate of ACTH-secreting adenomas was 84.6% (225/266) on MRI scans, and that of small microadenomas was 87.2% (34/39) on dynamic enhanced MRI scans. Preoperative endocrinological tests of 199 cases supported the diagnosis of typical Cushing's disease, while the other 67 cases had atypical endocrinological results. The endocrinological cure rate, remission rate, and inefficacy rate were 85.7%, 7.9%, and 6.4%, respectively. There was no difference in the initial endocrinological cure rate between the patients with positive and normal MRI results (90% vs. 87.8%, P = 0.904).
  
  
  CONCLUSIONS
  Enhanced coronal pituitary MRI is helpful for preoperative localization of ACTH-secreting pituitary microadenoma. Dynamic enhanced MRI may improve detection rate of microadenoma. There is no marked difference in the surgical results for patients with preoperative MRI results indicating presence or absence of microadenoma.
authors.affiliation: Department of Neurosurgery, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing 100730. xingbingemail@yahoo.com.cn
authors.forename: Bing
authors.initials: B
authors.lastname: Xing
authors.forename: Kan
authors.initials: K
authors.lastname: Deng
authors.forename: Zu-yuan
authors.initials: ZY
authors.lastname: Ren
authors.forename: Chang-bao
authors.initials: CB
authors.lastname: Su
authors.forename: Ren-zhi
authors.initials: RZ
authors.lastname: Wang
authors.forename: Yi
authors.initials: Y
authors.lastname: Yang
authors.forename: Wen-bin
authors.initials: WB
authors.lastname: Ma
authors.forename: Yong-ning
authors.initials: YN
authors.lastname: Li
mesh_terms: D000236:Adenoma / Q000175:diagnosis* / Q000378:metabolism / Q000601:surgery; D000293:Adolescent; D000324:Adrenocorticotropic Hormone / Q000378:metabolism*; D000328:Adult; D002648:Child; D005260:Female; D006801:Humans; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D008875:Middle Aged; D010911:Pituitary Neoplasms / Q000175:diagnosis* / Q000378:metabolism / Q000601:surgery
chemical_list: D000324:Adrenocorticotropic Hormone