Prediction of deep neck abscesses by contrast-enhanced computerized tomography in 76 clinically suspect consecutive patients.

OBJECTIVES/HYPOTHESIS: Contrast-enhanced computerized tomography (CECT) has become the imaging method of choice in patients with clinical suspicion of a deep neck abscess. The purpose of this retrospective study was to assess the predictive value of the diagnosis of deep neck abscess using CECT.

STUDY DESIGN: Retrospective chart review study over a 5-year period from 2002 to 2007 by a blinded observer.

METHODS: CECT examinations of patients with clinical suspicion of a deep neck abscess were reviewed for the presence of fluid collections, rim enhancement, and abnormal air collections, which we considered as indicative for an abscess. Additionally, the location and extension of the abnormalities were documented.

RESULTS: In this series of 76 patients, 61 adults and 15 children, fluid collections with complete or partial rim enhancement were seen in 65 patients. In two patients large abnormal air collections were seen with nonenhancing fluid accumulation in all deep spaces. Final diagnosis was confirmed by surgery in 57 patients. In 36 patients, two or more adjacent compartments were involved. Nine patients with an abscess were treated successfully by intravenous antibiotics only. The positive predictive value (PPV) for the presence of an abscess was 82% (53/65) if all radiological signs were included. The PPV was 67% (8/12) for fluid collections without rim enhancement. Air within or adjacent to a fluid collection or excessive free air between the fascias indicated an abscess in all cases. Negative predictive value (prediction of no abscess) was 100%.

CONCLUSIONS: The predictive value of the diagnosis deep neck abscess by CECT is high, with a PPV of 82%. The presence of air indicates abscess in all cases.