title: Carotid and vertebral artery stenosis evaluated by contrast-enhanced MR angiography in nasopharyngeal carcinoma patients after radiotherapy: a prospective cohort study.
abstract: OBJECTIVE
  To investigate the incidence of carotid artery (CA) and vertebral artery (VA) stenosis by contrast-enhanced MR angiography (CE-MRA) in patients with nasopharyngeal carcinoma (NPC) after radiotherapy.
  
  
  METHODS
  72 patients with NPC after radiotherapy more than 3 years ago were recruited as irradiation group to investigate the incidence and degree of CA and VA stenosis by CE-MRA. The results were compared with those of the control group, which comprised 50 newly diagnosed patients with NPC who had not received radiotherapy.
  
  
  RESULTS
  There was a higher incidence of CA and VA stenosis in the irradiation group than in the control group in terms of patient number as well as vessel involvement. The incidence of significant (>50%) CA and VA stenosis, except for the basilar artery, was also higher in the irradiation group than in the control group. The most commonly detected stenosis in the irradiation group was found in the internal CA (ICA) and VA, followed by the external CA and common CA (CCA). CCA and/or ICA (CCA/ICA) stenosis was present in 67 (93.1%) of 72 patients, with 27 (37.5%) patients having significant CCA/ICA stenosis. The statistical analysis demonstrated that age at receiving CE-MRA scanning and time interval from radiotherapy were the independent predictors of significant CCA/ICA stenosis.
  
  
  CONCLUSIONS
  The CE-MRA scanning results showed that the incidence of stenosis seems to exist in a wider range of CAs and VAs in the patients with NPC after radiotherapy than in the patients who had not received radiotherapy, and the incidence of significant CCA/ICA stenosis is higher in patients with older age and longer interval from radiotherapy.
  
  
  CONCLUSIONS
  Radiation-induced CA and VA stenosis exists widely in patients with NPC after radiotherapy, and its prevalence is more common in patients with older age and longer interval from radiotherapy.
authors: 1 Department of Radiology, The Second Affiliated Hospital of Soochow University, Suzhou, China.
authors: L
authors: L
authors: Zhou
authors: P
authors: P
authors: Xing
authors: Y
authors: Y
authors: Chen
authors: X
authors: X
authors: Xu
authors: J
authors: J
authors: Shen
authors: X
authors: X
authors: Lu
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002277:Carcinoma; D016893:Carotid Stenosis / Q000175:diagnosis* / Q000209:etiology*; D016022:Case-Control Studies; D003287:Contrast Media; D005260:Female; D006801:Humans; D015994:Incidence; D018810:Magnetic Resonance Angiography / Q000379:methods*; D008297:Male; D008875:Middle Aged; D000077274:Nasopharyngeal Carcinoma; D009303:Nasopharyngeal Neoplasms / Q000532:radiotherapy*; D014715:Vertebrobasilar Insufficiency / Q000175:diagnosis* / Q000209:etiology*
chemical_list: D003287:Contrast Media