The accuracy of lateral X-ray and computed tomography in diagnosis of paediatric retropharyngeal abscess: A systematic review

Abstract

Background: A systematic review was performed analysing the accuracy of lateral radiograph (XR) and computed tomography (CT) in the diagnosis of paediatric retropharyngeal abscess (RPA). The primary outcome measurement was the sensitivity, specificity, negative predictive value (NPV) and positive predictive value (PPV) of these two modalities compared to the operative findings. Methods: A systematic search was performed using the PubMed, MEDLINE and EMBASE databases following the Preferred Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. Studies that investigated and compared XR and/or CT findings with operative findings in paediatric RPA were included for analysis. Results: Twelve studies met final defined criteria. A large discrepancy in the accuracy of XR was noted in six papers. The ten studies that analysed CT showed far less variance. CT was a sensitive test with a strong NPV although was less specific with a weaker PPV. Conclusions: There is no consensus regarding XR in the diagnosis of paediatric RPA. No recent literature exists to support its use. The data that does exist is contradictory and is at risk of substantial bias. The literature is more recent and uniform on the merit of CT, acknowledging it as a sensitive diagnostic test that provides helpful anatomical and operative information. However, CT has a weak specificity (and PPV) and given that a proportion of RPAs respond to medical management alone, early ENT consultation is recommended. This will help guide initial medical management and imaging if needed, with CT as the primary modality choice.