title: Magnetic resonance imaging appearance of the medial wall of the cavernous sinus for the assessment of cavernous sinus invasion by pituitary adenomas.
abstract: OBJECTIVE
  The diagnostic criteria for cavernous sinus invasion (CSI) by pituitary adenomas are still unsatisfactory and controversial. For this reason, the study examined the appearance of the medial wall of the cavernous sinus (MWCS) on proton-density-weighted (PDW) magnetic resonance imaging (MRI) to determine its value for preoperative assessment of CSI.
  
  
  METHODS
  A 3.0-Tesla MRI scanner was used to obtain preoperative PDW images and conventional MRI sequences of 48 consecutive pituitary adenomas, and the MWCS was examined in PDW images to determine the presence of CSI in comparison to surgical findings and three traditional MRI criteria: Knosp grading system (KGS); percentage of encasement of the internal carotid artery (PEICA); and replacement of cavernous sinus compartments (RCSC) by tumors. The value of the MWCS as seen on MRI was compared with that of the Ki-67 labelling index (Ki-67 LI).
  
  
  RESULTS
  CSI images showed that continuity of the MWCS was interrupted and that tumor tissue had infiltrated the cavernous sinus (CS) compartments through the defects. In 96 CSs from 48 patients, the sensitivity of MRI visualization of the MWCS for detection of CSI was 93.3% with a specificity of 93.8%, which was significantly higher than with KGS, PEICA and RCSC (P=0.007, P=0.008 and P=0.056, respectively). Histopathological results showed no significant differences between MRI visualization of the MWCS and the Ki-67 LI.
  
  
  CONCLUSIONS
  PDW imaging permits adequate visualization of the MWCS and is superior to traditional diagnostic criteria for the detection of CSI, providing accurate preoperative images for intraoperative navigation.
authors.affiliation: Department of Neurosurgery, Fuzhou General Hospital, 156, Xihuanbei Road, Fuzhou Fujian 350025, China; Capital Medical University, Beijing Neurosurgical Institute, 6, Tiantanxili, Beijing 100050, China.
authors.forename: Lei
authors.initials: L
authors.lastname: Cao
authors.forename: Hongjie
authors.initials: H
authors.lastname: Chen
authors.forename: Jingfang
authors.initials: J
authors.lastname: Hong
authors.forename: Ming
authors.initials: M
authors.lastname: Ma
authors.forename: Qun
authors.initials: Q
authors.lastname: Zhong
authors.forename: Shousen
authors.initials: S
authors.lastname: Wang
mesh_terms: D000236:Adenoma / Q000473:pathology* / Q000601:surgery; D000328:Adult; D000368:Aged; D002426:Cavernous Sinus / Q000473:pathology* / Q000601:surgery; D005260:Female; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D009361:Neoplasm Invasiveness; D010911:Pituitary Neoplasms / Q000473:pathology* / Q000601:surgery; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity
keywords: Cavernous sinus; Magnetic resonance imaging; Medial wall; Pituitary adenoma; Proton-density-weighted imaging