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Research and Literature

See below for research and literature indicating safety and effectiveness of endoscopy for swallowing assessment. If you don’t have the time or resources to read all of the below, we suggest you spend a few minutes and read this one as it encompasses all of the key points:


Langmore, S.E. (2017). History of Fiberoptic Endoscopic Evaluation of Swallowing for Evaluation and Management of Pharyngeal Dysphagia: Changes over the Years. Dysphagia, 32: 27. doi;10.1007/s00455-016-9775-x.

1. Bedside clinical swallow exams by SLPs have proven to be under-estimating and over-estimating aspiration; therefore, the use of instrumental swallow evaluations is imperative.

2. There are certain risk factors in the SNF population that are predictors of aspiration pneumonia.

  • O’Horo, John C. et al. (2016). “Bedside Diagnosis of Dysphagia: A Systematic Review.” Journal of Hospital Medicine, 256–265

  • Gerrie J.J.W. Bours, Rene´e Speyer, Jessie Lemmens, Martien Limburg & Rianne de Wit. (2008). Bedside screening tests vs. videofluoroscopy or fibreoptic endoscopic evaluation of swallowing to detect dysphagia in patients with neurological disorders: systematic review. Journal of Advanced Nursing, 477-493.

  • Langmore, S.E., Skarupski, K.A., Park, P.S., & Fries, B.E. (2012). Predictors of aspiration pneumonia in nursing home residents. Dysphagia.

  • Leder, S.B., Espinosa, M.S. (2002). Aspiration risk after acute stroke: comparison of clinical examination and fiberoptic endoscopic evaluation of swallowing. Dysphagia,17:214-218.

  • Smith CH, Logemann J.A., Colangelo L.A., Rademaker A.W., & Pauloski B.R. (1999). Incidence and patient characteristics associated with silent aspiration in the acute care setting. Dysphagia, 14:1-7.

  • Smithard, D.G., O’Neill, P.A., Park, C., et al. (1998). Can bedside assessment reliably exclude aspiration following acute stroke? Age and Ageing, 27i(2), 99-106.

  • Murray, J, Langmore, S.E., Ginsberg, S. & Dostie, A. (1996). The significance of oropharyngeal secretions and swallowing frequency in predicting aspiration. Dysphagia,11, 99-103.

  • Langmore, S.E. & Logemann, J.A. (1991). After the clinical bedside swallowing examination: What next? American Journal of Speech Language Pathology,13-20.

1. Videofluoroscopy is not the only "Gold Standard" in dysphagia assessment and management.

2. FEES is just as accurate and with even better sensitivity and specificity than MBSS.

  • Mor, V., Intrator, O., Feng, Z., & Grabowski, D. C. (2010). The Revolving Door of Rehospitalization From Skilled Nursing Facilities. Health Affairs (Project Hope), 29(1), 57–64.

  • Coleman, E.A., Min, S., Chomiak, A., & Kramer, A.M. (2004). “Post-Hospital Care Transitions: Patterns, Complications, and Risk Identification.” Health Services Research, 37(5):1423-1440.

  • Donelan-McCall, N., Eilertsen, T., Fish, R., & Kramer, A.M. (2006). Small Patient Pop- ulation and Low Frequency Event Effects on the Stability of SNF Quality Measures. Washington, DC: MedPAC.

1. Evidence of aspiration/penetration after the swallow, and how fatigue can impact swallow function can be appreciated to a greater level on FEES because the recording lasts longer than the MBSS.

2. The direct visualization, in color, of anatomy during FEES allows for assessment of tissue/muscle function and anatomical variants, providing insight into the true etiology for the dysphagia.

3. FEES has proven to be a good assessment of vocal cord function and saliva management, high risk factors associated with aspiration pneumonia.

4. FEES allows the clinician to observe the transition from breathing to apnea during swallowing

5. Aspiration occurs about 25% of the time BEFORE the swallow, about 10% DURING the swallow, and about 65% AFTER the swallow.

  • Takahashi, N, Kikutani, T, Tamura, F., Groher, M., & Kuboki, T. (2012). Videoendoscopic assessment of swallowing function to predict the future incidence of pneumonia of the elderly. Journal of Oral Rehabilitation, 39; 429-437.

  • Butler, S.G., Maslan, J., Stuart, A., Leng, X., Wilhelm, E., Lintzenich, C.R., Williamson, J., & Kritchevsky, S.B. (2011). Factors influencing bolus dwell times in healthy older adults assessed endoscopically.  Laryngoscope, Dec; 121(12): 2526-34.

  • Allen, J.E., White, C.J., Leonard, R.J., & Belafsky, P.C (2010). Prevalence of penetration and aspiration on videofluoroscopy in normal individuals without dysphagia.  Journal of Otolaryngology Head and Neck Surgery, 142(2): 208-13.

  • Warnecke, T., Ritter, M.A., Kroger, B., Oelenberg, S., Teismann, I., Heuschmann, P.U., Ringelstein, E.B., Nabavi, D.G., & Dziewas, R. (2009). Fiberoptic endoscopic dysphagia severity scale predicts outcome after acute stroke. Cerebrovascular Disease, 28(3):283-9

  • Aviv, J.E. (2000). Prospective, randomized outcome study of endoscopy vs. modified barium swallow in patients with dysphagia. Laryngoscope,  100, 563-574.

  • Leder, S.B. & Sasaki, C.T. (2001). Use of FEES to assess and manage patients with head and neck cancer. In Langmore, S.E., editor. Endoscopic evaluation and treatment of swallowing disorders. New York: Thieme; 201-212.

  • Smith, C.H., Logemann, J.A., Colangelo, L.A., Rademaker, A.W., & Pauloski, B.R. (1999). Incidence and patient characteristics associated with silent aspiration in the acute care setting. Dysphagia, 14: 1-7.

  • McCulloch T.M., Langmore S.E., Palmer P.M, & Jaffe D. (1998). Timing of glossopharyngeal events during swallow: a combined electromyographic and endoscopic evaluation. Dysphagia,13:123.

  • McCulloch T.M., Langmore S.E., & Palmer P.M. (1997). Timing of glottis closure during swallow: a combined electromyographic and endoscopic evaluation. Dysphagia, 12:111.

  • Murray, J., Langmore, S.E., Ginsberg, S., & Dostie, A. (1996). The significance of accumulated oropharyngeal secretions and swallowing frequency in predicting aspiration.  Dysphagia, 11:99-103.

1. Of the potential risks associated with endoscopy, including gagging, epistaxis, laryngospasm, and vasovagal response; a mild case of epistaxis is the most prevalent.

2. The rate of complications associated with FEES is less than 1% overall.


3. FEES has proven to be a safe and well tolerated method of assessing swallow function when performed by a trained Speech Language Pathologist.

4. Studies show that endoscope placement does not adversely affect swallow function.

  • Nacci, A., Matteucci, J., Romeo, S.O., Santopadre, S., Cavaliere, M.D., Barillari, M.R., Berrettini, S., & Fattori, B. (2016). Complications with Fiberoptic Endoscopic Evaluation of Swallowing in 2,820 Examinations. ENT, Audiology and Phoniatrics Unit, Department of Neurosciences, University of Pisa, Italy. Folia Phoniatr Logop, 68(1):37-45. 

  • Warnecke, T., Teismann, I., Oslenber, S., Hamacher, C., Ringelstein, E.B., Schabitz, W.R., & Dziewas, R. (2009). The safety of fiberoptic endoscopic evaluation of swallowing in acute stroke patients. Stroke, 40(2):482-6.

  • Suiter, D. M., & Moorhead, M. K. (2007). Effects of flexible fiberoptic endoscopy on pharyngeal swallow physiology. Otolaryngology-Head and Neck Surgery, 956-858.

  • Aviv, J.E., Murray, T., Zschommler, A., Cohen, M., & Gartner, C. (2005).  Flexible endoscopic evaluation of swallowing with sensory testing: patient characteristics and analysis of safety in 1340 consecutive examinations.  Annals of Otology, Rhinology & Laryngology,114:173-176.

  • Cohen, M.A., Setzen, M., Perlman, P.W., Ditkoff, M., Mattucci, K.F., Guss, J. (2003). The safety of flexible endoscopic evaluation of swallowing with sensory testing in an outpatient otolaryngology setting.  Laryngoscope, 113:21-24.

  • Aviv, J.E., Kaplan, S.T., Thompson, J.E., Spitzer, J., Diamond, B., Close, L.G. (2000). The safety of flexible endoscopic evaluation of swallowing with sensory testing: an analysis of 500 consecutive evaluations. Dysphagia,15:39-44.

  • Wu, C.H., Hsiao, T.Y., Chen, J.C., Chang, Y.C., &Lee, S.Y. (1997). Evaluation of swallowing safety with fiberoptic endoscope: Comparison with video fluoroscopic technique.  Laryngoscope, 107, 396-401.

Literature Supporting the Need for Instrumental Swallow Evaluations

Literature Comparing Efficacy of FEES vs MBSS

Literature Showing Support for FEES in Reducing Hospital Re-Admissions

Literature Listing Information Obtainable Through FEES

Literature Examining Safety and Comfort of FEES

References borrowed with permission from our friends at Mobile Dysphagia Diagnostics.

Doctor's Desk


Providing patients with a collaborative, evidence-based, cost effective assessment that is a GOLD STANDARD in swallowing diagnostics since 2017.

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