FEES® vs VFSS
What is FEES®?
Fiberoptic Endoscopic Evaluation of Swallowing - FEES®
A nasoendoscopic procedure for assessing the pharyngeal stage of swallowing to detect aspiration and to determine the safety of oral feeding in patients with dysphagia and for whom the traditional videofluoroscopic evaluation may be difficult or impossible to perform (Langmore, Schatz, & Olsen, 1988). This procedure uses a small endoscope that is inserted transnasally into and through the nose and into the pharynx (throat). In addition to determining swallow safety, it may also be used to determine whether certain behavioral treatment approaches are beneficial for improving swallowing efficiency and safety. A video recording of this procedure may be used for patient counseling, medical staff training, or become part of the patient’s medical record.
What is VFSS?
Video Fluoroscopic Swallow Study - VFSS
A radiographic study (fluoroscopy) using ionized radiation to examine the movement patterns of the oral cavity, pharynx, and esophagus during swallowing. This study is a modification of the routine barium swallow study using measured amounts of food consistencies mixed with barium sulfate, and is administered within the confines of the radiology suite of a hospital.
Compare FEES® to VFSS
Safety, Validity, Usefulness and Efficacy of FEES®
Susan Langmore, Ph.D, was instrumental in developing the modified nasoendoscopic evaluation of swallowing in the 1980s. Subsequently, the procedure has gained significant credentials as a reliable, valid and safe procedure for assessing oropharyngeal swallowing functions. Dr. Langmore has published an excellent review paper, which can be found at the website: http://www.nature.com. In addition, over 100 references to FEES® can be found on the Pubmed website (www.ncbi.nlm.nih.gov). Below is a brief synopsis of Dr. Langmore’s discussion of safety, validity, usefulness and efficacy of the FEES® procedure.
Concern initially arose over Speech-Language Pathologists (SLP) performing the FEES® procedure. These concerns included allowing a non-emergency medically trained person (SLP) to perform an invasive procedure on another person and the use of topical anesthesia by a non-medically trained person. Subsequently, these issues have now been addressed and these concerns largely satisfied, particularly when FEES® is performed in protected medical settings. Langmore cites four studies of the safety of FEES® and found the rate of complications was less than 1%. In a recent study (Warnecke et al.,2009), FEES® was found to be a safe and well-tolerated method of assessing swallowing function when performed by a Speech-Language Pathologist and Neurologist. A review of Pubmed listed 5 studies specially addressing the safety of the procedure, and its safe use by a trained SLP.
Langmore addresses the issue of SLPs missing medical pathologies, such as cancer, and stresses it is not the purpose of the FEES® procedure to identify medical pathologies. SASS clinicians have over 46 years of combined experience, and it is the policy of SASS to report, and if possible, send still-photos of the suspect lesion separately to the nursing facility resident’s primary physician. Further, follow-up endoscopic evaluation by an Otolaryngologist is always recommended.
How accurate and how sensitive is the FEES® procedure for identifying abnormal swallowing events? The longstanding “gold standard” has been the videofluoroscopy swallow study (VFSS). There are at least nine studies listed at the www.nature.com source showing that FEES® has very good sensitivity (>0.88) and specificity of 0.50 or greater when compared to the videofluoroscopy study. Further these studies have shown a high level of agreement, particularly for detecting aspiration. With years of experience administering and interpreting fluoroscopy swallow studies, the SLPs at SASS report that detection of aspiration and pharyngeal stasis using the FEES® examination appears to be more sensitive than is appreciated with fluoroscopy. Quantitatively, the amounts and locations of food material left in the pharynx and larynx appear to be much greater than is seen on the VFSS. A recent study by Kelly (2007) substantiated this impression. They reported that penetration and aspiration were perceived to be greater (more severe) using FEES® than those seen in fluoroscopic images.
“Gold standard” may not be totally accurate for either of the instrumental swallowing assessment studies. Both assessments are not 100% accurate due to many factors including the mediums themselves, clarity of images, time between swallows, clinician perception of event activities, etc. However, as indicated above, both instrumental studies are sensitive and valid. However, when both instrumental assessments are compared to the Clinical Dysphagia (Bedside) Examination, both instruments have far better sensitivity and specificity to detecting aspiration than does the very subjective bedside assessment (Smithard,et al.,1998; Leder & Espinosa, 2002). As Langmore states, both of the instrumental assessment tools “can rightfully be called the gold standard.”
There are few reliability studies on the FEES® procedure and is an area ripe for research. A few studies have been reported and show fluoroscopic study and the FEES® procedure have very similar reliability scores.
Langmore reports several studies describing the use of FEES® with different populations: postsurgical patients, neurologically-impaired patients, pediatrics, cancer patients, etc., and in different environments: intensive care, rehabilitation settings, and longer term care facilities. Predominantly the studies have been with neurological patients mainly due to the high incidence of swallowing disorders among this population. More studies are being reported using FEES® with cancer patients and with children. One area where little research has been reported is in the use of FEES® is in the long-term nursing facilities. This assessment approach appears to be tailor made of this environment and population given the high dysphagia prevalence, and difficulty obtaining videofluoroscopic swallow studies due to distance, travel, costs, and availability. Further, many nursing facility residents improve after leaving an acute care setting, but are not subsequently reassessed. As noted above, the Clinical Dysphagia (Bedside) Assessment lacks adequate sensitivity to accurately diagnose changes in swallowing and feeding statuses. FEES® easily fills that void and provides up-to-date and relevant information on the resident.
Studies of efficacy, like reliability, are lacking for both the videofluoroscopic study and the FEES® procedure. Only one randomized outcome study has been reported. Aviv (2000) reported no significant difference in the abilities of the two instruments to guide treatment and prevent pneumonia in 126 outpatients with dysphagia.
Aviv J.E. (2000). Prospective, randomized outcome study of endoscopy vs. modified
barium swallow in patients with dysphagia. Laryngoscope, 100, 563–574.
Kelly, A.M. (2007). Assessing penetration and aspiration: How do videofluoroscopy and
fiberoptic endoscopic evaluation of swallowing compare? The Laryngoscope,
Leder, S.B & Espinosa, J.F. (2002). Aspiration risk afer acute stroke: Comparison of
clinical examination and fiberoptic endoscopic evaluation of swallowing.
Dysphagia, 17(3), 214-218.
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.
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.Retrieved July 18, 2009 from www.stroke.ahajournals.org.