Think ultrasound first for peritonsillar swelling.

Peritonsillar abscess (PTA) is one of the most common deep neck space infections that can potentially have life-threatening complications if inadequately diagnosed and not treated promptly. The ability of clinicians to reliably differentiate PTA from peritonsillar cellulitis by physical examination alone is limited and blind needle aspiration, the typical method of diagnosis of PTA, is also unreliable. We review the available evidence supporting the use of ultrasound, either intraoral ultrasound or transcutaneous ultrasound to be the initial imaging modality of choice for evaluation of PTA and be used for real-time needle guidance.