A more sensitive evaluation is through a computed tomography scan of the retropharynx. A ring-enhanced lesion in this area is suggestive of an abscess. The presence of air within the lesion confirms that an abscess is present.
Once an abscess is diagnosed or suspected, either by air within the area of swelling, by CT scan evaluation, or by failure to improve on antibiotics a drainage procedure in the operating room is required. This is performed under general anesthesia.