There are over 500 published articles that either focus on the validity, reliability, or utility of FEES or that use FEES as the diagnostic tool in a study of a patient population that has dysphagia. Some articles that I have authored or co-authored that focus on or utilize FEES, are the following:



Fiberoptic endoscopic examination of swallowing safety: a new procedure.
Langmore SE, Schatz K, Olsen N. Dysphagia. 1988;2(4):216-9. No abstract available. PMID: 3251697  
This was the first published study of a new procedure using flexible fiberoptic laryngoscopy to evaluate swallowing.  The protocol was described, indications for the exam and scoring of findings were presented. (Note: the editors of the journal insisted that the name of the new procedure be FEESS stating that it could assess “swallow safety” but not ‘swallowing itself".

We largely ignored this advice but kept the second ’S’ in this single article to please the editors. 



Endoscopic and videofluoroscopic evaluations of swallowing and aspiration Langmore SE, Schatz K, Olson N. Ann Otol Rhinol Laryngol. 1991 Aug;100(8):678-81. PMID: 1872520  
Presence of spillage, residue, penetration, and aspiration were determined from FEES exams compared to fluoroscopy exams given to the same patients with dysphagia.  Comparing FEES to fluoroscopy, sensitivity, specificity, positive predictive value and negative predictive values for the FEES exams were very high, indicating that these bolus findings were very similar in the 2 exams.



Indications and techniques of endoscopy in evaluation of cervical dysphagia: comparison with radiography. Kidder TM, Langmore SE, Martin BJ. Dysphagia. 1994 Fall;9(4):256-61. Review. PMID: 7805425



The significance of accumulated oropharyngeal secretions and swallowing frequency in predicting aspir

Murray J, Langmore SE, Ginsberg S, Dostie A. Dysphagia. 1996 Spring;11(2):99-103. PMID: 8721067
69 participants including young, healthy adults, elderly healthy adults, and elderly hospitalized patients were given a FEES exam. Prior to delivering food or liquid, secretion status was scored. The hospitalized patients were the only group that included some subjects with excess secretions in the laryngeal vestibule. Those patients with laryngeal secretions were the only participants who aspirated food or liquid, suggesting that laryngeals secretions are highly predictive of aspiration.



Laryngeal sensation: a touchy subject.

Langmore SE. Dysphagia. 1998 Spring;13(2):93-4. No abstract available. PMID: 9513303 (Editorial)



Role of flexible laryngoscopy for evaluating aspiration.

Langmore SE. Ann Otol Rhinol Laryngol. 1998 May;107(5 Pt 1):446. No abstract available. PMID: 9596227 (Editorial)



Evaluation of oropharyngeal dysphagia: which diagnostic tool is superior? Langmore SE. Curr Opin Otolaryngol Head Neck Surg. 2003 Dec;11(6):485-9. Review. PMID: 14631184
A review of the literature compared fluoroscopy to endoscopy up to 2003. Both exams were revealed to be valuable and the term ‘gold standard’ applied to fluoroscopy was deemed inappropriate. Both examinations were in need of standardization.



Timing of glottic closure during swallowing: a combined electromyographic and endoscopic analysis. Van Daele DJ, McCulloch TM, Palmer PM, Langmore SE. Ann Otol Rhinol Laryngol. 2005 Jun;114(6):478-87. PMID: 16042106
Four healthy young volunteers were studied to better understand the timing of events to attain airway closure during the swallow. Hook wire EMG, endoscopy, and respiratory signals were utilized. Airway closure began with arytenoid medial and anterior movement, followed by epiglottic retroflexion, and finally by adduction of the true vocal folds. This was in contrast to the order of airway closure for breath holding which started with VF closure. The super supraglottic swallow was able to alter the normal order of events.


A documentation system to save time and ensure proper application of the fiberoptic endoscopic evalua (FEES®). Hey C, Pluschinski P, Stanschus S, Euler HA, Sader RA, Langmore S, Neumann K. Folia Phoniatr Logop. 2011;63(4):201-8. doi: 10.1159/000316314. Epub 2010 Oct 12. PMID: 20938202
A new documentation system for scoring FEES exams was developed, largely based on the Scoring components described by Langmore in her textbook. Four examiners analyzed 12 FEES recorded procedures both with and without the documentation system. The documentation system reduced time to report from 42 to 27 minutes and increased report completeness



The Boston residue and clearance scale: preliminary reliability and validity testing.

Kaneoka AS, Langmore SE, Krisciunas GP, Field K, Scheel R, McNally E, Walsh MJ, O'Dea MB, Folia Phoniatr Logop. 2013; 65(6):312-7. doi: 10.1159/000365006. Epub 2014 Jul 12. PMID: 25033761
An ordinal scale for rating residue and clearance from a FEES exam was developed and called BRACS (Boston Residue and Clearance Scale). Initial reliability and internal validity were determined from the ratings given to 63 sample swallows by 4 raters. BRACS showed excellent inter-rater reliability and high concurrent validity and internal consistency.



The effects of topical anesthetic on swallowing during nasoendoscopy.

Lester S, Langmore SE, Lintzenich CR, Wright SC, Grace-Martin K, Fife T, Butler SG. Laryngoscope. 2013 Jul;123(7):1704-8. doi: 10.1002/lary.23899. Epub 2013 Apr 2. PMID: 23553259
This was the first of a 3-part study that assessed whether the use of lidodaine in a FEES exam affected swallow function and /or led to greater patient comfort. 25 healthy normal subjects were given 1 ml of lidocaine or a sham spray prior to a FEES exam.  There was a significant rise in the PAS scores in the lidocaine condition, suggesting that the anesthetic did affect swallowing. However, the anesthesia condition was rated significantly more comfortable than the sham condition by the participants.



Use of Topical Nasal Anesthesia During Flexible Endoscopic Evaluation of Swallowing in Dysphagic Patients

Fife TA, Butler SG, Langmore SE, Lester S, Wright SC Jr, Kemp S, Grace-Martin K, Rees Lintzenich C Ann Otol Rhinol Laryngol. 2014 Sep 9. pii: 0003489414550153. [Epub ahead of print] PMID: 25204714
This was the second of a 3 part study that assessed whether the use of lidodaine in a FEES exam affected swallow function and /or led to greater patient comfort. In this study, 25 patients with dysphagia were examined and the dosage of lidocaine was dropped to 0.5ml of iidocaine. Either the anesthetic or a sham spray were administered. There was no significant difference in the PAS scorse in the 2 conditions but it was ‘nearly’ significant.  Self-rated patient comfort was significantly better in the anesthetic condition.



Effect of lidocaine on swallowing during FEES in patients with dysphagia.

O’Dea M, Langmore S, Krisciunas G, Walsh M, Zanchetti L, Scheel R, McNally E, Kaneoka A, Guarino A. Annals of Otol Rhin Laryn 2014 31 Oct.
This was the third in a series that assessed whether the use of lidocaine in a FEES exam affected swallow function and/or led to greater patient comfort.  In this study, the dosage of lidocaine was dropped to 0.1 ml . There was no true sham condition but rather adminiatration  of 0.1 ml of neosynephrine nasal decongestant. 17 patients with dysphagia were given a FEES. There were no significant differerences in PAS scores for any of the bolus consistencies in the 2 conditions but the patients rated the anesthetized condition significantly more comfortable. This suggests that 0.5ml of lidocaine applied to one nares as a topical anesthesia does not adversely affect swallowing in patients with dysphagia and it makes the exam more comfortable for many persons.



A Comparison of 2 Methods of Endoscopic Laryngeal Sensory Testing: A Preliminary Study.

Kaneoka A, Krisciunas GP, Walsh K, Raade AS, Langmore SE. Ann Otol Rhinol Laryngol. 2014 Sep 14. pii: 0003489414550241. [Epub ahead of print] PMID: 25225213
Following a FEES exam, a comparison of the air pulse method and the touch method for testing sensory awareness was carried out with 14 patients with dysphagia. Results showed that the air pulse method was more sensitive to detecting sensory impairment but that only the touch method was significantly associated with penetration of liquid boluses during the FEES exam.

Research Using FEES

Fiberoptic Endoscopic Evaluation of Swallowing

Langmore FEES