title: Atlas of confounding factors in head and neck PET/CT imaging.
abstract: OBJECTIVE
  Interpretation of positron emission tomography/computed tomography (PET/CT) studies in the head and neck region is challenging due to the complex anatomy and nonspecific physiologic and inflammatory FDG uptake. We present an atlas of common confounding factors encountered at our institution.
  
  
  METHODS
  We present whole-body fluorodeoxyglucose (FDG) PET/CT studies of 20 patients with various confounding factors in the head and neck. Most patients (15) had a history of head and neck cancer and some (5) of them presented with other primary tumors.
  
  
  RESULTS
  We describe these cases under the following categories: physiologic uptake (6), inflammatory uptake (5), unexpected benign tumors (2), unexpected malignant tumors (4), postradiation changes (2), postsurgical changes (2), and misregistration (1).
  
  
  CONCLUSIONS
  Knowledge of common variants, pitfalls, and treatment effects is essential in accurate reading of PET/CT in the head and neck region.
authors.affiliation: Department of Nuclear Medicine and Radiology, Michael E. DeBakey VA Medical Center, Houston, TX, USA. Peeyush.bhargava@va.gov
authors.forename: Peeyush
authors.initials: P
authors.lastname: Bhargava
authors.forename: Saiyyeda
authors.initials: S
authors.lastname: Rahman
authors.forename: Juliet
authors.initials: J
authors.lastname: Wendt
mesh_terms: D016477:Artifacts; D001692:Biological Transport; D019788:Fluorodeoxyglucose F18 / Q000378:metabolism; D006257:Head / Q000000981:diagnostic imaging* / Q000528:radiation effects / Q000601:surgery; D006801:Humans; D007090:Image Interpretation, Computer-Assisted / Q000379:methods*; D007249:Inflammation / Q000000981:diagnostic imaging / Q000378:metabolism; D008297:Male; D009333:Neck / Q000000981:diagnostic imaging* / Q000528:radiation effects / Q000601:surgery; D009369:Neoplasms / Q000000981:diagnostic imaging / Q000378:metabolism; D049268:Positron-Emission Tomography / Q000379:methods*; D014057:Tomography, X-Ray Computed / Q000379:methods*
chemical_list: D019788:Fluorodeoxyglucose F18