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Three Part Question

In [adults presenting to the emergency department with a suspected peritonsillar abscess (PTA)] is [intraoral ultrasound and guided needle aspiration better than the traditional landmark-based technique] at [allowing successful diagnosis and subsequent drainage]?

Clinical Scenario

A 30-year-old woman comes to the emergency department presenting with sore throat and low-grade fever. Physical examination reveals a non-toxic-appearing woman with mild trismus and uvular deviation. As you consider whether the symptoms represent cellulitis or a true abscess, you wonder if using intraoral ultrasound could help establish a definitive diagnosis and assist in needle aspiration.

Search Strategy

Medline using NHS Evidence 16 July 2014: [(exp ultrasonograpy OR ultrasound, ti, ab) AND (exp peritonsillar abscess)] LIMIT to English Language

Embase using NHS Evidence 16 July 2014: [(exp ultrasound OR ultrasonography, ti, ab) AND (exp peritonsillar abscess)] LIMIT to English Language, Human.

The Cochrane Library Issue 6 of 12 June 2014: peritonsillar abscess:ti,ab,kw (Word variations have been searched).

Search Outcome

Twenty-seven unique results papers were identified, of which one was a randomised controlled trial that directly answered the clinical question.

Relevant Paper(s)

Author, date and country	Patient group	Study type (level of evidence)	Outcomes	Key results	Study Weaknesses
Costantino et al, 2012, USA	28 emergency department patients with signs and symptoms of peritonsillar abscess (PTA) Landmark (LM)-based needle aspiration (14) vs ultrasonic-guided (UG) diagnosis and aspiration (14). In the latter group, aspiration was only attempted if ultrasound examination demonstrated an anechoic or hypoechoic area consistent with an abscess	Randomised controlled trial	Correct identification of PTA	50% (5 of 10) vs 100% (8 of 8). p=0.04	Ultrasound evaluations were performed by experienced residents whose proficiency with ultrasound may not be comparable with the average practicing emergency physician. Ultrasound was the gold standard for pus detection Residents also had less experience in LM-based aspiration than Ear-Nose-Throat (ENT) surgeons. Follow-up physicians not blinded to results of initial ultrasound evaluation
			Successful aspiration of purulent fluid from true PTA	50% vs 100%

Comment(s)

This study enrolled a small number of patients, but it showed promising results in the potential use of ultrasound in diagnosing and treating PTA (quinsy). The study also showed that emergency physician-performed ultrasound can reliably distinguish true PTA from peritonsillar cellulitis and thus avoid unnecessary invasive procedures. Further research could validate these findings and may also explore dynamic use of ultrasound during PTA aspiration.

Clinical Bottom Line

Emergency physician-performed intraoral ultrasound can reliably diagnose peritonsillar abscess and leads to greater success at aspiration when compared with the traditional landmark technique.

References

1. Costantino TG, Satz WA, Dehnkamp W et al . Randomized trial comparing intraoral ultrasound to landmark-based needle aspiration in patients with suspected peritonsillar abscess. Acad Emerg Med 2012;19:626–31.