Feasibility of an inexperienced examiner using trans-cervical ultrasound in the diagnosis of peritonsillar abscesses

Abstract

Background A peritonsillar abscess (PTA) is a common complication to acute tonsillitis. Needle aspiration (NA) is the gold standard for diagnosis of PTA. NA is usually painful and not risk-free. Ultrasound (US) is a noninvasive, portable radiological modality that could potentially be used in the diagnosis of PTA and selection of patients for NA. The reliability of US is dependent on the experience of the examiner which limits is usefulness. Aim To evaluate the reliability of US in the diagnosis of PTA by an inexperienced examiner. Methods Thirty patients with suspected PTA were included. They were first examined with trans-cervical US by a medical student then clinically examined by a physician that performed a NA if clinically motivated. They were then followed for at least two days. Results Three patients were excluded from analysis because no NA was performed. In these patients, US correctly classified them as negative for PTA. In the remaining 27 patients, the sensitivity and negative predictive value was 100%. The specificity was 64.3% and the positive-predictive value was 72.2%. Conclusion US can be very useful in the diagnosis of PTA and the selection for NA even with an inexperienced examiner. Significance The results highlight the usefulness of ultrasound in otolaryngology.