Contribution of CT scan and CT-guided aspiration in the management of retropharyngeal abscess in children based on a series of 18 cases.

OBJECTIVE: This study was designed to analyse the contribution of CT scan to the management of retropharyngeal abscess in children and the place of CT-guided percutaneous aspiration as an alternative to surgical drainage.

MATERIALS AND METHODS: Retrospective study including 18 children with a mean age of 38 months [range: 5-67 months] presenting with retropharyngeal infection between 2006 and 2011. All cases were initially assessed by contrast-enhanced CT scan of the neck. Clinical, radiological treatment and bacteriological data were collected. Radiological results were correlated with surgical and percutaneous aspiration findings (presence or absence of an abscess).

RESULTS: The initial CT scan detected 14 abscesses, 3 cases of non-suppurative lymphadenitis and one case of retropharyngeal oedema. One case of non-suppurative lymphadenitis progressed to abscess after failure of antibiotic therapy and was treated surgically. Surgical drainage revealed a purulent collection in 11 cases and no collection in 3 cases. Four CT-guided percutaneous aspirations were successfully performed. Three cases were treated by antibiotics alone (2 cases of lymphadenitis and 1 case of retropharyngeal oedema). Bacteriological examinations revealed the presence of Streptococcus pyogenes in 78.5% of cases. The positive predictive value of the initial CT scan was 78.8% in our series.

CONCLUSION: Contrast-enhanced neck CT scan confirmed the diagnosis of retropharyngeal abscess and the indication for surgical drainage. It must be performed urgently, on admission. When it is decided to treat the patient with antibiotics alone, follow-up imaging should be performed in the absence of improvement 24 to 48 hours after starting antibiotics. CT-guided percutaneous aspiration is both a diagnostic modality confirming abscess formation of an inflammatory lesion of the retropharyngeal space as well as a therapeutic tool, sometimes avoiding the need for surgical drainage.