Intraoral Ultrasound in the Diagnosis and Treatment of Suspected Peritonsillar Abscess in the Emergency Department

Abstract

Peritonsillar abscess (PTA) can be a life-threatening disease and may lead to significant complications without drainage. Objectives: To describe the utility of ultrasound (US) in the evaluation of potential PTA and US-guided PTA drainage. Methods: The authors performed a retrospective US quality assurance review of all patients over 18 years of age scanned by emergency physicians for possible PTA. All patients presenting with PTA signs and symptoms including erythema and swelling of the tonsillar pillar and uvular deviation were eligible to be scanned. Patients confirmed to have an abscess on US had US-guided drainage followed by intravenous antibiotics in the emergency department and discharge home on oral antibiotics. Scans were performed by credentialed attending emergency physicians and residents. Researchers recorded patient symptoms, US findings, results of abscess drainage if performed, and any complications of drainage. All US examinations were performed with sheathed endocavity broadband US transducers on minimum depth and maximum resolution settings. Statistical analysis included descriptive statistics. Results: Forty-three patients received intraoral US examinations for suspected PTA. Thirty-five (81%) were diagnosed as having abscess on US. All abscesses were drained with an 18-or 14-gauge needle under US guidance. There were no drainage complications. There was one false positive with a focal area of edema yielding no pus on needle aspiration under direct US visualization. No patient returned unexpectedly after drainage. Conclusions: These data suggest that intraoral US of suspected PTA allows for reliable diagnosis and safe and accurate abscess drainage. Key words: peritonsillar abscess; peritonsillar abscess drainage; peritonsillar ultrasound; emergency ultrasound; intraoral ultrasound; ultrasound-guided procedure. ACADEMIC EMERGENCY MEDICINE 2005; 12:85-88. Peritonsillar abscess (PTA), the most common deep infection of the head and neck, consists of suppuration outside the tonsillar capsule as a consequence of acute tonsillitis.1 Often presenting in the emergency department (ED) setting with the clinical picture of trismus, odynophagia, ''hot potato'' voice, edema and erythema of the superior peritonsillar tissue, and soft palate deviation away from the infected side, 2 PTA can be a life-threatening disease that must be drained in order to resolve.2 Death can occur through rupture into the airway, dissection into the carotid artery, or regional spread of infection leading to sepsis. In most ED settings, diagnosis and subsequent drainage are accomplished using blind needle aspiration of the suspected abscess.2 However, blind needle aspiration is an invasive, painful procedure that has a reported false-negative rate of 10-24%. [3][4][5] In addition, a serious complication of blind needle aspiration of the suspected abscess is laceration of the carotid artery. 2Due to the recent increased availability of ultrasound (US) equipment in the ED, it is now possible for suspected PTA to be imag...

Randomized Trial Comparing Intraoral Ultrasound to Landmark‐based Needle Aspiration in Patients with Suspected Peritonsillar Abscess

“…The residents’ familiarity with US and lack of experience with PTA may have led to an overstatement of their success with US and an understatement of the success with LM compared to the average EP. Nevertheless, with US guidance, PTA was successfully drained in 100% of the patients in this study, which is similar to previous studies 7,8 . Intraoral US seems to be a useful tool for EPs to successfully drain a PTA.…”

“…An interesting finding of our study was the relatively high incidence of PTC (36%). Although similar to previously published rates of 20% to 30%, we thought our study design, which required needle aspiration in the LM arm, would tend to minimize the cases of PTC as only the most clinically suspicious cases of PTA would be enrolled 6,8 . Viewing our results from another perspective, 64% of the patients in the LM group had unsuccessful needle aspiration by the EP versus 0% in the US group.…”

“…A much larger trial may be necessary to attempt to show differences in those two methods. Although previous studies have shown that EPs could successfully diagnose PTA with intraoral US, we believe that this is the first prospective, comparative trial 7,8 …”

“…Therefore, emergency physicians (EPs) have begun to use intraoral ultrasound (US) as a way to improve diagnostic and procedural success. Early studies suggested intraoral US to be accurate in diagnosing PTA and assisting in its successful drainage 7,8 . Despite its growing use, this is the first comparative trial of intraoral US to diagnose and guide drainage of a PTA versus traditional landmark‐based methods of inspection and needle aspiration by EPs.…”

The Patient with Sore Throat

“…Ultrasound has been used increasingly by emergency room physicians for locating the pus when performing incision and drainage, with good reliability. 26 Radiographs will show soft tissue thickening and possibly the presence of air within soft tissue; however, radiographs are not the imaging modality of choice if one is needed. Computed tomography (CT) and ultrasound can be useful adjuncts when the picture is unclear or when the abscess is located inferiorly.…”