title: Pitfalls of CT for deep neck abscess imaging assessment: a retrospective review of 162 cases.
abstract: OBJECTIVE
  To investigate the diagnostic value of contrast-enhanced computed tomography (CT) for the prediction of deep neck abscesses in different deep neck spaces and to evaluate the false-positive results.
  
  
  METHODS
  We retrospectively analysed the clinical charts, CT examinations, surgical findings, bacteriology, pathological examinations and complications of hospitalised patients with a diagnosis of deep neck abscess from 2004 to 2010. The positive predictive values (PPV) for the prediction of abscesses by CT scan in different deep neck spaces were calculated individually on the basis of surgical findings.
  
  
  RESULTS
  A total of 162 patients were included in this study. All patients received both intravenous antibiotics and surgical drainage. The parapharyngeal space was the most commonly involved space. The overall PPV for the prediction of deep neck abscess with contrast-enhanced CT was 79.6%. The PPV was 91.3% when more than one deep neck space was involved but only 50.0% in patients with isolated retropharyngeal abscesses. In the false-positive group, cellulitis was the most common final result, followed by cystic degeneration of cervical metastases. Five specimens taken intra-operatively revealed malignancy and four of these were not infected.
  
  
  CONCLUSIONS
  There are some limitations affecting the differentiation of abscesses and cellulitis, particularly in the retropharyngeal space. A central necrotic cervical metastatic lymph node may sometimes also mimic a simple pyogenic deep neck abscess on both clinical pictures and CT images. Routine biopsy of the tissue must be performed during surgical drainage.
authors: Department of Otorhinolaryngology, Head and Neck Surgery, Changhua Christian Hospital, Changhua, Taiwan.
authors: S Y
authors: SY
authors: Chuang
authors: H T
authors: HT
authors: Lin
authors: Y S
authors: YS
authors: Wen
authors: F J
authors: FJ
authors: Hsu
mesh_terms: D000038:Abscess / Q000000981:diagnostic imaging* / Q000601:surgery; D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001935:Branchioma / Q000000981:diagnostic imaging / Q000601:surgery; D002481:Cellulitis / Q000000981:diagnostic imaging*; D002648:Child; D002675:Child, Preschool; D003937:Diagnosis, Differential; D004322:Drainage; D005189:False Positive Reactions; D005260:Female; D006258:Head and Neck Neoplasms / Q000000981:diagnostic imaging / Q000601:surgery; D006801:Humans; D007223:Infant; D008198:Lymph Nodes / Q000000981:diagnostic imaging; D008207:Lymphatic Metastasis; D008297:Male; D008875:Middle Aged; D009333:Neck; D010608:Pharyngeal Diseases / Q000000981:diagnostic imaging / Q000601:surgery; D011237:Predictive Value of Tests; D017703:Retropharyngeal Abscess / Q000000981:diagnostic imaging / Q000601:surgery; D012189:Retrospective Studies; D014057:Tomography, X-Ray Computed / Q000379:methods; D055815:Young Adult