Transoral Ultrasound Versus no Transoral Ultrasound in Diagnostic Workup of Peritonsillar Abscess

NCT07577232 | Recruiting DMC

• 1 other identifier: VMK2501007
• Study Type: interventional
• Target: 368
• Locations: 1 country
• Sites: 3

Brief Summary

Peritonsillar abscess (PTA) is a collection of pus between the palatine tonsil and the constrictor muscle. PTA is detected by recognizing characteristics during clinical examination: redness, pain, malaise, trismus, and unilateral peritonsillar swelling. Clinical assessment, including inspection and palpation, is the traditional diagnostic method for patients suspected of having PTA. If PTA is suspected, aspiration with a large-gauge needle or incision is performed to drain the abscess . It can be challenging to distinguish PTA and peritonsillar cellulitis (PTC) based on clinical examination alone. Due to the increased availability of point-of-care ultrasound, it is a part of the diagnostic workup of PTA. Several studies have shown that transoral US can improve the diagnostic accuracy of patients with a suspected PTA. However, no large multicenter study has evaluated whether one of these methods is superior to the other. It is therefore very clinician-dependent whether the patient will have a transoral US performed or not. The investigators hypothesize that transoral US will increase the diagnostic accuracy of PTA compared to solely clinical examination, which is a visual and palpatory assessment. This will result in fewer unnecessary aspiration attempts and overlooked PTAs. Additionally, the investigators wish to investigate the number of aspirations of transoral US-guided needle aspirations compared to aspirations without ultrasound. Methods This is a cluster randomized study. Patients with suspected PTA will be randomized 1:1 to groups A and B. The cluster randomization will happen weekly using an online randomization tool. Participants are patients refeered to the outpatient clinic on suspicion of a peritonsillar absces. The primary outcome is the diagnostic accuracy The investigators aim to determine whether transoral US is a standard part of the clinical examination by comparing clinical examinations with and without US.

Conditions

Peritonsillar Abscess; Peritonsillar Cellulitis; Tonsillitis

Keywords

Transoral ultrasound; peritonsillar abscess; Peritonsillar cellulitis

Outcome Measures

Primary Outcomes (1)

• Diagnostic accuracy

  Diagnostic accuracy (sensitivity and specificity) of PTA when performing transoral US and by clinical evaluation. A final PTA diagnosis is defined as pus retriveal on the first visit in the outpatient clinic or follow up visit. No later than four days after inclusion. A final non-PTa diagnosis is defined as disease resolution with conservative treatment

  From date of randomization until the treatment is completed, assessed up to 2 months.

Secondary Outcomes (9)

• Number of patients undergoing surgery (tons a chaud)

  From date of randomization until the treatment is completed, assessed up to 2 months.

• Number of positive needle aspirations

  Day 1

• Number of hospital visits

  From date of randomization until the treatment is completed, assessed up to 2 months.

• Number of days hospitalized

  From date of randomization until the treatment is completed, assessed up to 2 months.

• Number of needle aspirations performed

  Two measures: At baseline and From date of randomization until the final visit in the outpatient clinic assessed up to 2 months.

Study Arms (2)

Intervention/clinical investigation with ultrasound

EXPERIMENTAL

Intervention group Transoral ultrasound A head and neck surgeon, often an ENT resident, will perform the transoral ultrasound. A hockey stick transducer is used for transoral ultrasound diagnostics. The procedure is performed by placing the transducer in a disposable glove filled with ultrasound gel. Transoral ultrasound is initiated by positioning the transducer on the palatoglossal arch and a cranial to caudal sweep of the tonsil.The affected tonsil and its surroundings are scanned. An abscess will appear as a hypoechoic area between the tonsil and the constrictor muscle or inside the tonsil. There will be no flow in an abscess when Color Doppler is applied. The unaffected tonsil and the surrounding area can be scanned as a reference. If randomization is with transoral ultrasound, the aspiration attempts can be performed ultrasound-guided.

Device: Transoral Ultrasound

Investigation without ultrasound. Control group.

ACTIVE COMPARATOR

No ultrasound Standard diagnostic workup and treatment All patients with suspected PTA receive a clinical head and neck examination, including visual inspection of the mouth and throat, and a flexible fiberoptic laryngoscopy (to assess the extent of the abscess in the pharynx and possible edema). If a PTA is suspected, needle aspiration will be performed, followed by relevant antibiotics. Before transoral ultrasound and needle aspiration, a spray of topical anesthetic (lidocaine spray 10 mg/dose) will be applied. In some cases, for example, if the patient has previously had a PTA, an acute tonsillectomy is offered. If the examination does not reveal a PTA, the patients will receive conservative treatment with relevant antibiotics. The patients will be scheduled for a 24-48-hour follow-up if the physician deems it necessary.

Device: Transoral Ultrasound

Interventions

Transoral Ultrasound DEVICE

A small hockey stick ultrasound to scan the oropharynx through the mouth

Intervention/clinical investigation with ultrasound; Investigation without ultrasound. Control group.

Eligibility Criteria

• Age: 18 Years+
• Sex: all
• Healthy Volunteers: No
• Age Groups: Adult (18-64), Older Adult (65+)

You may qualify if:

• Patients referred to the ENT outpatient clinic with a suspected PTA.
• years of age or older.

You may not qualify if:

• Unable to understand the verbal information, participating in research.
• Prior surgical interventions (needle aspiration, surgery, incision) during the course of the disease.
• Compromised airways, needing acute airway management.

Sponsors & Collaborators

• Rigshospitalet, Denmark: lead

Study Sites (3)

Department of Otorhinolaryngology, Head and Neck Surgery & Audiolog

Copenhagen, 2100, Denmark

RECRUITING

Department of Otorhinolaryngology, Head and Neck Surgery & Audiology, North Zealand Hospital

Hillerød, Denmark

RECRUITING

Department of ORL - Head & Neck Surgery and Audiology, Zealand University Hospital,

Køge, Denmark

NOT YET RECRUITING

MeSH Terms

Conditions

Peritonsillar Abscess; Tonsillitis

Condition Hierarchy (Ancestors)

Pharyngitis; Respiratory Tract Infections; Infections; Abscess; Suppuration; Pharyngeal Diseases; Stomatognathic Diseases; Respiratory Tract Diseases; Otorhinolaryngologic Diseases

Study Design

• Study Type: interventional
• Phase: not applicable
• Allocation: RANDOMIZED
• Masking: NONE
• Purpose: DIAGNOSTIC
• Intervention Model: PARALLEL
• Sponsor Type: OTHER
• Responsible Party: PRINCIPAL INVESTIGATOR
• PI Title: MD, PhD, Professor

Model Details: Cluster randomization

Study Record Dates

• First Submitted: January 23, 2026
• First Posted: May 11, 2026
• Study Start: June 9, 2025
• Primary Completion: June 1, 2026
• Study Completion: July 1, 2026
• Last Updated: May 11, 2026

Record last verified: 2026-04

Locations

DK (3)