What is FEES (Fiberoptic Endoscopic Evaluation of Swallowing)?

What is FEES (Fiberoptic Endoscopic Evaluation of Swallowing)?

FEES is a bedside or clinic-based instrumental swallowing assessment that involves transnasal passage of a flexible nasopharyngoscope to directly visualize the pharynx and larynx before and after swallowing. 1

Procedure Overview

• FEES involves passing a fiberoptic laryngoscope transnasally to visualize the hypopharynx, larynx, and proximal trachea during swallowing assessment 2
• The procedure can be performed at the bedside or in a clinic area, making it highly portable and practical 1, 3
• Direct observation of the pharynx and larynx occurs before and after the swallow, providing real-time anatomical and functional information 1

What FEES Can Identify

FEES provides comprehensive assessment of multiple swallowing parameters that directly impact aspiration risk and patient safety:

• Structural assessment: Laryngeal morphology and motility, velo-pharyngeal closure competence 1
• Functional deficits: Impaired chewing, tongue muscle deficit, cough reflex sensitivity 1
• Safety indicators: Detection of pharyngeal residues, visualization of secretion pooling 1
• Anatomical visualization: Pharyngeal and laryngeal anatomy assessment 3

Clinical Utility and Advantages

• FEES is considered an efficient method for assessment of oropharyngeal dysphagia 1
• The procedure allows determination of the safest and least restrictive level of oral intake 2
• FEES enables implementation of appropriate compensatory techniques and identification of dysphagia rehabilitation plans 2
• It is particularly valuable for detecting silent aspiration, which occurs in up to 55% of patients who aspirate 3

Guideline Recommendations

The American College of Chest Physicians recommends that patients with dysphagia should undergo either videofluoroscopic swallow evaluation (VSE) or FEES to identify appropriate treatment (Grade B recommendation). 1

• The American Geriatrics Society recommends instrumental assessment (including FEES) when signs of dysphagia are present at clinical evaluation, silent aspiration is suspected, or the clinical scenario is unclear 3
• Bedside clinical evaluations alone are insufficient to determine treatment interventions for dysphagia 3

Comparison to Other Methods

• FEES has been compared with modified barium swallow (videofluoroscopy) and reports demonstrate that FEES is as sensitive as, or even more sensitive, for swallowing assessment 2
• Unlike videofluoroscopy, FEES does not involve radiation exposure and can be performed at bedside 3
• FEES provides direct visualization of anatomy and physiology during deglutition, unlike clinical swallow evaluations which rely on subjective judgments 1

Practical Considerations

• The procedure is generally well tolerated, though 3% of patients in one series could not tolerate the examination 2
• FEES can be performed safely across the age spectrum, from premature infants to older adults 4, 5
• The examination should be performed through teamwork involving a speech-language pathologist and otolaryngologist collaborating together 2
• Patients must be able to participate in the assessment; performing swallowing assessments on delirious patients may be futile 3

Common Pitfalls

• FEES cannot visualize the actual moment of swallowing due to "white-out" when the pharynx contracts, unlike videofluoroscopy which captures the entire swallow sequence 1
• The procedure requires adequate patient cooperation and cannot be performed on patients with lethargy, reduced level of consciousness, or inability to manage oral secretions 6
• Potential risks include discomfort, gagging/vomiting, vasovagal syncope, epistaxis, mucosal perforation, adverse reactions to topical anesthetics, and laryngospasm, necessitating informed consent 7