title: The pterygopalatine fossa: postoperative MR imaging appearance.
abstract: OBJECTIVE
  The pterygopalatine fossa (PPF) is an important anatomic location of the deep portion of the face. It is essential to review this area on both pre- and posttreatment studies of head and neck malignancies to assess local extent of disease or recurrence and perineural tumor spread. The purpose of this study was to review the postoperative appearance of the PPF on MR images.
  
  
  METHODS
  Imaging and clinical data of 10 patients who underwent surgical resection of tumor in which the PPF was violated at surgery were reviewed. Patients were included in the study if there was no imaging or clinical evidence of tumor in the PPF pre- or postoperatively. Postoperative MR studies were examined to assess the appearance of the PPF.
  
  
  RESULTS
  The PPF is consistently and persistently abnormal after surgical violation. There is loss of the normal T1 signal hyperintensity and abnormal, increased contrast enhancement, as seen on fat-suppressed T1-weighted images. These postoperative changes are strikingly similar to those of tumor involvement.
  
  
  CONCLUSIONS
  After surgical violation, the PPF will always appear abnormal on MR images, and the expected imaging findings must be recognized to avoid the misdiagnosis of tumor recurrence.
authors.affiliation: Department of Diagnostic Radiology, The University of Texas M.D. Anderson Cancer Center, Houston 77030, USA.
authors.forename: L L
authors.initials: LL
authors.lastname: Chan
authors.forename: J
authors.initials: J
authors.lastname: Chong
authors.forename: A M
authors.initials: AM
authors.lastname: Gillenwater
authors.forename: L E
authors.initials: LE
authors.lastname: Ginsberg
mesh_terms: D000368:Aged; D003937:Diagnosis, Differential; D005260:Female; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D008443:Maxillary Sinus / Q000473:pathology / Q000601:surgery; D008444:Maxillary Sinus Neoplasms / Q000175:diagnosis / Q000601:surgery*; D008875:Middle Aged; D009364:Neoplasm Recurrence, Local / Q000175:diagnosis*; D010159:Palate / Q000473:pathology / Q000601:surgery*; D011183:Postoperative Complications / Q000175:diagnosis*; D011626:Pterygoid Muscles / Q000473:pathology / Q000601:surgery*