title: A false aneurysm.
abstract: OBJECTIVE
  We report a case of a remaining hemi-thyroid following laryngectomy, which was misinterpreted as a pseudoaneurysm.
  
  
  METHODS
  Case report and comment on this understandable error which is easily avoidable.
  
  
  RESULTS
  A 59-year-old man had undergone salvage laryngectomy for recurrent squamous cell carcinoma of the larynx, which had previously been treated with radiotherapy. Three months after his laryngectomy, he presented with a sore neck and subcutaneous collections. Computed tomography revealed a unilateral mass with high signal contrast uptake anterior to the left common carotid artery, which was thought initially to be a carotid pseudoaneurysm. Further investigation, including ultrasonography and a review by the senior head and neck radiologist, demonstrated that this mass was actually the remnant hemi-thyroid preserved at laryngectomy (which is often misshapen compared with a normal hemi-thyroid). The collections were found to be recurrent tumour, and unnecessary further interventions were avoided.
  
  
  CONCLUSIONS
  Ultrasonography easily distinguishes between a thyroid remnant and a pseudoaneurysm. Furthermore, the opinion of an experienced head and neck radiologist may be vital when interpreting complex post-surgical head and neck radiology.
authors.affiliation: Department of Otolaryngology, Princess Alexandra Hospital, University of Queensland, Brisbane, Queensland, Australia.
authors.forename: D
authors.initials: D
authors.lastname: Mitchell
authors.forename: C
authors.initials: C
authors.lastname: Repanos
authors.forename: W B
authors.initials: WB
authors.lastname: Coman
mesh_terms: D017541:Aneurysm, False / Q000000981:diagnostic imaging*; D002294:Carcinoma, Squamous Cell / Q000000981:diagnostic imaging / Q000473:pathology / Q000601:surgery*; D002343:Carotid Artery, Internal / Q000000981:diagnostic imaging; D003937:Diagnosis, Differential; D005122:Exudates and Transudates; D005189:False Positive Reactions; D006801:Humans; D007822:Laryngeal Neoplasms / Q000000981:diagnostic imaging / Q000473:pathology / Q000601:surgery*; D007825:Laryngectomy; D008297:Male; D008875:Middle Aged; D009333:Neck / Q000473:pathology; D037981:Neck Dissection; D019547:Neck Pain; D009364:Neoplasm Recurrence, Local / Q000175:diagnosis*; D011182:Postoperative Care; D011859:Radiography; D016879:Salvage Therapy; D013961:Thyroid Gland / Q000000981:diagnostic imaging*; D013965:Thyroidectomy; D014463:Ultrasonography