Evaluation of oropharyngeal dysphagia: which diagnostic tool is superior? Susan E. Langmore

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1 Evaluation of oropharyngeal dysphagia: which diagnostic tool is superior? Susan E. Langmore Purpose of review As flexible endoscopic examinations of swallowing become more widely used to evaluate patients with oropharyngeal dysphagia, it is important to be aware of research regarding the efficacy of this procedure as compared with the videofluoroscopy procedure. A recent evidence-based review of the field threw some long-held findings into question and has stimulated a surge of new research studying the sensitivity of the two instrumental examinations, health outcomes of patients who receive each procedure, and a look at different patient outcomes. Recent findings Since 1999, one quasi-randomized clinical trial has directly compared outcomes of patients given a fluoroscopy versus a fiberoptic endoscopic evaluation of swallowing (FEES) examination. This study showed no significant difference in pneumonia rates between the two groups of patients. A multitude of studies have shown a high level of agreement between the two instrumental examinations, and the use of the term gold standard as applied to fluoroscopy is no longer appropriate. The attempt to standardize each examination has been slow, and inter-judge reliability of results has come under fire. Several new scales for quality of life and functional status are now ready to be applied to research that can measure outcomes other than pneumonia. Summary Research to date has suggested that both instrumental examinations are valuable. It is likely that both will continue to be used and will be seen as complementary rather than competitors. Keywords dysphagia, evaluation studies, flexible endoscopy, fluoroscopy Curr Opin Otolaryngol Head Neck Surg 11: Lippincott Williams & Wilkins. From the Departments of Otolaryngology-Head & Neck Surgery and Neurology, University of California, San Francisco, California, USA Correspondence to Susan E. Langmore, PhD, UCSF Speech and Swallowing Center, 2380 Sutter St., San Francisco, CA , USA Tel: ; fax: ; langmor@itsa.ucsf.edu Current Opinion in Otolaryngology & Head and Neck Surgery 2003, 11: Abbreviations FEES fiberoptic endoscopic evaluation of swallowing FEESST fiberoptic endoscopic evaluation of swallowing plus sensory testing RCT randomized clinical trial 2003 Lippincott Williams & Wilkins Introduction Dysphagia can be a symptom of a multitude of underlying medical diseases and a handful of psychiatric conditions or psychological problems. Otolaryngologists are often the first-line physician to see patients with dysphagia, especially when the symptom is related to head and neck cancer or if the underlying condition is unknown. When dealing with an unknown medical condition, laryngologists may screen for evidence of a swallowing dysfunction during their clinical examination, and most will refer the patient to a speech pathologist for a complete evaluation. The referring physician is reliant on an accurate, sensitive swallowing evaluation to help reveal the underlying medical diagnosis that will lead to appropriate treatment options or appropriate referrals. When a patient with a known head and neck cancer reports dysphagia, the cause of the symptom may be obvious, but a physician s referral of a patient to a speech pathologist for a comprehensive evaluation is still valuable. The examination may guide the physician s decision regarding need for a feeding tube or may provide prognostic information regarding the patient s ability to resume a more normal oral diet at some point in the future. The evaluation should, at the very least, provide guidance to the patient regarding how he or she can eat more safely and efficiently with the use of dietary modifications or behavioral strategies. For many years, the videofluoroscopy examination has been the mainstay for evaluating oropharyngeal dysphagia. Logemann adapted the traditional barium swallow procedure in several ways [1,2]. Her procedure examines the oral and pharyngeal regions, uses several different food and liquid consistencies, and usually has the patient remain in an upright position. Once the problem is identified, the examiner intervenes with postural or behavioral strategies to change the dynamics and lessen the problem. The entire examination is recorded for review afterwards. For the past 20 years, this procedure has been used by speech pathologists in medical settings to identify a swallowing problem and to understand the nature of the problem. It has served the profession very well and is in no danger of being abandoned. However, as with all examinations, it has its limitations. Gradually, since 1988, flexible laryngoscopy has grown in use as another tool to evaluate oropharyngeal dysphagia. A procedure was formalized by Langmore [3] and called a fiberoptic endoscopic evaluation of swallowing (FEES) examination. This procedure was given a copyright to 485

2 486 Laryngology and bronchoesophagology distinguish it from the standard laryngology examination to diagnose medical pathology and from a simple laryngeal screening to identify aspiration. A FEES examination includes three components: a physical examination of structural movements, delivery of different food and liquids, and intervention with dietary or behavioral alterations to lessen the problem. Like the fluoroscopy examination, it is recorded and viewed afterwards. The purpose of a FEES or videofluoroscopy examination is identical: to identify and interpret the nature of the swallowing problem and to probe for therapeutic interventions. Users of this tool sing its praises as loudly as do the proponents of fluoroscopy. A recent state of the art review in a peer-reviewed otolaryngology journal suggested that it was the preferred examination [4 ]. So, the referring otolaryngologist must wonder: Is one tool preferable? Should I request a specific procedure? When? And most importantly, does it matter? An evidence-based report on dysphagia In the past 10 years, the infusion of evidence-based medicine into clinical practice has changed the way we select our diagnostic and therapeutic procedures. Instead of relying primarily on our own clinical experience and advice from mentors and colleagues, we now give significant weight to procedures and treatments that have been proven effective in systematic research studies, particularly the randomized clinical trial (RCT) [5]. This yardstick for measuring the value of therapeutic interventions has not spared the world of oropharyngeal dysphagia. In 1999, the U.S. Department of Health and Human Services, Agency for Health Care Policy and Research (AHCPR; now the Agency for Healthcare Research and Quality, AHRQ) published Evidence Report/ Technology Assessment on Diagnosis and Treatment of Swallowing Disorders in Acute-Care Stroke Patients [6 ]. This evidence-based report focused on acute stroke patients with dysphagia simply because this was the only patient group that had been submitted to research in large enough numbers to be analyzed. Four issues were addressed, three of which related to evaluation procedures. Unfortunately, the reviewers conclusions were tentative because of the preponderance of weak designs and few controlled trials. In brief, however, the reviewers concluded that (1) clinical programs for diagnosis and treatment of dysphagia with acute stroke patients, run mainly by speech pathologists, appear to yield dramatic reductions in pneumonia rates; (2) no screening tool has yet been developed that will adequately detect patients with dysphagia who need more extensive testing; and (3) neither fiberoptic endoscopy nor videofluoroscopy has been demonstrated to be superior in terms of patient outcomes or more sensitive for detection of aspiration. The reviewers noted that instrumental examinations undoubtedly reveal more information than the clinical bedside examinations, but evidence suggests that the clinical examination may provide equally valuable information for preventing pneumonia. There were no RCTs that directly compared the utility of these three procedures. The reviewers ended the report with a plea for RCTs to determine the comparative effectiveness of the various diagnostic tests. Although this report addressed efficacy with only one patient group, acute stroke patients with dysphagia, the conclusions drawn from it have been erroneously generalized by many readers to all dysphagia programs, serving both inpatients and outpatients with a variety of medical conditions. In 2003, dramatic changes in Medicare reimbursement for the videofluoroscopy evaluation were seen, putting it on a par with the clinical evaluation procedure in reimbursement value. This change was suspected by some clinicians to reflect the lessened value of the instrumental examination in the eyes of the government. Reimbursement for the endoscopic examination was not reduced, fortunately. However, good medicine should not be determined by reimbursement rates but by evidence that a procedure provides more useful information and better outcomes for patients than other procedures. With this in mind, the following critical review of research since 1999 is offered. Research efforts since 1999 In response to the government report, a group of experts met in August 2001 to discuss the future of dysphagia research [7]. The state of research in the field was summarized. Participants agreed on the need for more research in all areas of dysphagia but also expressed frustration with the lack of research funding, difficulty recruiting and following large samples of homogeneous patients, and difficulty identifying appropriate groups of patients to study. Although the AHCPR report favored use of homogeneous populations, the patients with dysphagia who are at most risk for pneumonia generally have multiple medical problems, not a single condition such as acute stroke. The group also argued that health outcomes may not be the best outcome measure in all studies; for example, quality of life and other functional outcomes may be most appropriate measures for outpatients. Since the evidence-based report in 1999 and the meeting of 2001, no large-scale clinical trials have been published comparing the three diagnostic procedures. One small quasi-randomized clinical trial has been published, along with several studies comparing the sensitivity and specificity of FEES to fluoroscopy. Both instrumental examinations have undergone validity testing. In addition, there have been many studies attempting to improve the sensitivity and specificity of the clinical bedside examination compared with instrumental examinations to identify patients with dysphagia and aspiration. More attention has been paid to developing scales to measure

3 Evaluation of oropharyngeal dysphagia Langmore 487 functional outcomes and quality of life. Thus, progress, albeit slow, is being made. Clinical trials The only prospective clinical trial comparing the two instrumental examinations for clinical outcomes since 1999 was reported by Aviv [8 ]. One hundred twentysix outpatients with dysphagia of various causes were quasi-randomized to a modified barium swallow test or a FEESST examination (FEES plus sensory testing), had their treatment based on the evaluation given to them, and were followed for 1 year for an outcome of pneumonia. Eighteen percent of the patients receiving the modified barium swallow test developed pneumonia while 12% of the patients who got a FEESST procedure developed pneumonia. This difference was not significantly different, suggesting that the two examinations were equivalent in their ability to guide safe feeding in patients and thereby prevent pneumonia. The authors must be applauded for taking on the challenge of determining which examination excelled in terms of patient outcomes. The fact that neither examination emerged as superior is noteworthy; however, the fact remains that these conclusions are preliminary. The small number of patients (63 in each group) made it very difficult to uncover a significant difference. With a larger sample size, perhaps one procedure would have emerged as more effective. In addition, the subjects were not homogeneous, as they had various medical conditions, and this may also have clouded the results. In fact, when the subgroup of stroke patients was analyzed separately, those who received the endoscopic procedure did have significantly less pneumonia than the patients who received the fluoroscopic procedure. In a more recent publication, Aviv et al. [9] compared the cost-effectiveness of the two instrumental examinations with head and neck cancer patients. They found that reimbursement for FEESST was significantly lower and thus more cost-effective for the government and tax payers. With no difference in outcomes, as shown in previous studies, cost-effectiveness becomes an important consideration. Ironically, since the publication of this study, reimbursement for the two instrumental procedures has completely reversed, with the endoscopic procedures yielding more reimbursement than fluoroscopy. The politics of reimbursement appears to change yearly, as health care policies and political power changes hands. Rather than simply looking at reimbursement for the actual procedure, we need to look at overall costs to the patient, the facility, and the government. Endoscopy utilizes cheaper equipment than fluoroscopy and has lower maintenance costs and minimal space overhead, so it appears to be the cost-based choice. More importantly, however, we need to tie cost-effectiveness to patient outcomes. The procedure that prevents health complications, gets the patient off feeding tubes and back to an oral diet, and does this most efficiently with fewest treatment sessions will be the most cost-effective procedure and the best one for the patient. Is there a gold standard? When Langmore et al. [10] introduced FEES as a new diagnostic tool, they needed to establish its validity. To do this, they determined its sensitivity, specificity, positive predictive value, and negative predictive value as compared with the more established fluoroscopy procedure. Langmore initially referred to the fluoroscopy procedure as the gold standard, meaning that it represented the truth as far as we could know. Since that date, many other similar studies have compared the two procedures and always identified fluoroscopy as the gold standard. These comparative studies have all revealed a high level of agreement between the two procedures for all salient findings. In the past few years, two additional studies have been published, with similar findings [11,12]. In this paradigm, however, when endoscopy identifies more instances of an abnormal finding, it is scored as a false-positive. It is now evident that this may be a false assumption, since there is no evidence that fluoroscopy is more sensitive than endoscopy. The AHCQR report [6 ] and Doggett et al. [13 ] both objected to this term, stating that it was inappropriate usage. At this point in time, neither test can be considered the gold standard for the other. It is only appropriate to use the term gold standard when calculating sensitivity, specificity, and predictive values of non-imaging tests, which are known to miss some findings, and comparing them to either of the instrumental examinations. In the past 10 to 15 years, many reports have been published of noninvasive clinical bedside examinations developed to detect patients with dysphagia or to detect aspiration. Although earlier studies consistently used fluoroscopy as the reference standard, or gold standard, several reports since 2000 have used endoscopy as the benchmark [14,15,16,17]. The intent of most of these published studies is to identify patients who need more extensive testing with instrumentation. In nursing home settings and in rural settings, however, there is a significant need for an adequate clinical examination that can stand alone, since instrumentation is not usually available to these residents. In my opinion, this may be an attainable goal, if the purpose of the evaluation is to prevent pneumonia. Research into the best predictors of aspiration pneumonia in elderly patients, including the author s [18,19] have identified risk factors that are equally important or more important than the presence of aspiration (for example, dependence for feeding and oral care). A good clinical examination may be able to

4 488 Laryngology and bronchoesophagology identify these risk factors and guide appropriate management. Progress toward standardizing the instrumental examinations One major problem with both fluoroscopy and endoscopy is the lack of widely used standardized protocols and scoring systems. Logemann developed a protocol in the early 1970s [20] which was modified in the 1980s to include use of different bolus sizes [21] and again in the 1990s to include systematic use of therapeutic interventions [22]. Many scoring systems have been developed, usually including a notation of bolus events such as aspiration or residue and a rating scale of adequacy of structural movements. Some research-clinicians advocate measuring structural movements with digital images and computerized software that would add objectivity to the scoring [23]. Similarly, several protocols have been developed for use with endoscopy. These also include notation of bolus events and adequacy of structural movements. Langmore described a protocol when the procedure was first introduced [3], which has been modified several times, the latest version being the most comprehensive [24 ]. In contrast to fluoroscopy, this protocol includes a standardized portion and a nonstandardized portion, in which the patient is asked to eat everything on the plate, to get a sense of his real-life eating function. Scoring a FEES examination is not yet standardized across all users, although scoring forms have been presented by Murray [25], Langmore [24 ], and others. In the past 20 years, virtually all reports of inter-judge reliability for scoring fluoroscopy studies have revealed inadequate reliability for judging most parameters of the swallow. Two recent reports [26,27 ] found that of all the measures, only the rating of aspiration reached acceptable levels of reliability from one observer to the next. There is a significant need to ameliorate this weakness in the study. In contrast to the many reliability studies for fluoroscopy, there has only been one study looking at inter-judge reliability for FEES [28 ]. This study only looked at judgements of penetration and aspiration and applied the 8-point Penetration-Aspiration scale, originally validated for fluoroscopy [26,29,30] to FEES studies. The authors found a high degree of reliability when viewing FEES studies, comparable to that reported for fluoroscopy. It will be very interesting to see whether inter-judge reliability for other parameters of the swallow, when viewing FEES studies, is any better than that reported for fluoroscopy. Conclusions As fluoroscopy and endoscopy are used more widely, research using both tools has proliferated. Both examination procedures have been successfully applied to various patient populations and ages, from pediatrics to the elderly, and both have been reported to manage patients with dysphagia successfully. Does this mean they are equivalent? By no means. The view obtained from each tool is entirely different and the portability of endoscopy is unique. The research has not yet revealed whether certain patient populations or types of problems are best served by one examination or the other, but clinical experience strongly suggests that this is true. For example, we know that if a patient reports globus or difficulty getting food through the region of the suprasternal notch, a fluoroscopy examination is more likely to reveal a problem with upper esophageal sphincter opening, esophageal transit, or gastroesophageal reflux disease than endoscopy. If a patient complains of a change in voice and aspiration during the swallow, a FEES examination is indicated to view laryngeal function and glottic competence. Fluoroscopy has come under intense scrutiny from a multitude of researchers, whereas FEES has not yet been subjected to nearly as much research. My clinical experience suggests that FEES has some advantages, but the results of future studies looking at critical issues, will be the final word. As a clinician, I consider both tools indispensable. Most importantly, our research efforts need to determine which procedure yields better patient outcomes. There has been one clinical trial suggesting that pneumonia outcomes are equivalent after having either a fluoroscopy or an endoscopy procedure. This needs to be replicated with a larger sample size to determine whether a difference emerges. In addition, we have not explored other outcomes. Will one examination be able to guide treatment more efficiently so that the duration and number of treatment sessions are shortened? Will the patient experience a quicker time to recovery or a quicker time to resumption of an oral diet? Will patients be more satisfied and compliant after having one examination or the other? All of these outcomes relate to patient satisfaction and quality of life, and, for society, it translates into costeffectiveness. Several new tools for measuring functional status and quality of life in patients with dysphagia have been developed in the past few years [31 37]; the time has now come to apply these tools to exciting research efforts. Our patients will be the beneficiaries. References and recommended reading Papers of particular interest, published within the annual period of review, have been highlighted as: Of special interest Of outstanding interest 1 Logemann JA: Evaluation and Treatment of Swallowing Disorders. Austin, TX: Pro-Ed Publishers, Logemann JA: Evaluation and Treatment of Swallowing Disorders, 2nd ed. Austin, TX: Pro-Ed Publishers, Langmore SE, Schatz K, Olsen N: Fiberoptic endoscopic examination of swallowing safety: a new procedure. Dysphagia 1988, 2: Hiss SG, Postma GN: Fiberoptic Endoscopic Evaluation of Swallowing. Laryngoscope 2003, 113: An excellent state-of-the-art review on FEES, including latest research and discus-

5 Evaluation of oropharyngeal dysphagia Langmore 489 sion of issues surrounding its use. Recommended for all clinicians working inthe field of dysphagia, especially otolaryngologists. 5 Sackett DL, et al.: Clinical Epidemiology: A Basic Science for Clinical Medicine, 2nd ed. Boston: Little, Brown and Company, AHCPR: Evidence report on diagnosis and treatment of dysphagia/ swallowing problems in the elderly. AHCPR Publication Clearinghouse. Vol This is the report that has spurred much research and controversy. Excellent but needs to be interpreted carefully. 7 Robbins J, et al.: Dysphagia research in the 21st century and beyond: proceedings from dysphagia experts. J Rehabil Res Dev 2002, 39: Aviv JE: Prospective, randomized outcome study of endoscopy vs. modified barium swallow in patients with dysphagia. Laryngoscope 2000, 100: The best clinical trial to date comparing the two instrumental procedures. A good model for future studies to follow. 9 Aviv JE, Sataloff RT, Cohen M, et al.: Cost-effectiveness of two types of dysphagia care in head and neck cancer: A preliminary report. ENT Ear Nose Throat J 2001, 80: Langmore SE, Schatz K, Olson N: Endoscopic and videofluoroscopic evaluations of swallowing and aspiration. Ann Otol Rhinol Laryngol 1991, 100: Schroter-Morasch H, Bartalome G, Troppmann N, Ziegler W: Values and limitation of pharyngolaryngoscopy (transnasal, transoral) in patients with dysphagia. Folia Phoniatr Logop 1999, 51: Madden C, Fenton J, Hughes J, Timon C: Comparison between videofluoroscopy and milk-swallow endoscopy in the assessment of swallowing function. Clin Otolaryngol 2000, 25: Doggett DL, Turkelson CM, Coates V: Recent developments in diagnosis and intervention for aspiration and dysphagia in stroke and other neuromuscular disorders. Current Atheroscler Rep 2002, 4: This is a critical, careful, unbiased summary of the state of dysphagia management to date. 14 Colodny N: Comparison of dysphagics and nondysphagics on pulse oximetry during oral feeding. Dysphagia 2000, 15: Lim SHB, Lieu PK, Phua SY: Accuracy of bedside clinical methods compared with Fiberoptic Endoscopic Examination of Swallowing (FEES) in determining the risk of aspiration in acute stroke patients. Dysphagia 2001, 16: Donzelli J, Brady S, Wesling M, Craney M: Simultaneous modified Evans blue dye procedure and video nasal endoscopic evaluation of the swallow. Laryngoscope 2001, 111: The modified blue dye procedure has been shown insensitive, even though these authors suggest it has some utility. 17 Leder SB: Aspiration risk after acute stroke: comparison of clinical examination and fiberoptic endoscopic evaluation of swallowing. Dysphagia 2002, 17: Langmore SE, Terpenning MS, Schork A, et al.: Predictors of aspiration pneumonia: how important is dysphagia? Dysphagia 1998, 13: Langmore SE, Skarupski KA, Park PS, Fries BE: Risk factors for aspiration pneumonia in nursing home residents. Dysphagia 2002, 17: Blonsky ER, Logemann JA, Boshes B, et al.: Comparison of speech and swallowing function in patients with tremor disorders and in normal geriatric patients: a cinefluorographic study. J Gerontol 1975, 30: Jacob P, Kahrilas PJ, Logemann JA, et al.: Upper esophageal sphincter opening and modulation during swallowing. Gastroenterology 1989, 97: Lazarus CL, Logemann JA, Rademaker AW, et al.: Effects of bolus volume, viscosity and repeated swallows in non-stroke subjects and stroke patients. Arch Phys Med Rehabil 1993, 74: Leonard RJ, Kendall KA, McKenzie S, et al.: Structural displacements in normal swallowing: a videofluoroscopic study. Dysphagia 2000, 15: Langmore SE: Endoscopic Evaluation and Treatment of Swallowing Disorders. New York: Thieme, The only comprehensive coverage of the FEES procedure, scoring, and interpretation of swallowing from an endoscopic view. Has many chapters by contributing authors on management and special populations. 25 Murray J: Dysphagia. In Manual of Dysphagia Assessment in Adults. Rosenbek JC, ed. San Diego: Singular Publishing Group, McCullough GH, Wertz RT, Rosenbek JC, et al.: Inter- and intrajudge reliability for videofluoroscopic swallowing evaluation measures. Dysphagia 2001, 16: Stoeckli SJ, Huisman TA, Seifert B, Martin-Harris BJ: Interrater reliability of videofluoroscopic swallow evaluation. Dysphagia 2003, 18: The latest in a series of articles on the problem of poor interrater reliability when scoring videofluoroscopy examinations. 28 Colodny N: Interjudge and intrajudge reliabilities in Fiberoptic Endoscopic Evaluation of Swallowing (FEES) using the Penetration-Aspiration scale: a replication study. Dysphagia 2002, 17: This is an extremely well-designed study, building on a scale originally developed for fluoroscopy, adapted to endoscopy. 29 Rosenbek JC, Robbins JA, Roecker EB, et al.: A penetration-aspiration scale. Dysphagia 1996, 11: Original article describing the validation of the scale. The high interjudge reliability with this scale is a reflection of the care taken to develop it and establish validity. 30 Robbins J, Coyle J, Rosenbek J, et al.: Differentiation of normal and abnormal airway protection during swallowing using the Penetration-Aspiration Scale. Dysphagia 1999, 14: Sallasa JR: A functional outcome swallowing scale for staging oropharyngeal dysphagia. Dig Dis Sci 1999, 17: Wallace KL, Middleton S, Cook IJ: Development and validation of a self-report symptom inventory to assess the severity of oral-pharyngeal dysphagia. Gastroenterology 2000, 118: McHorney CA, Bricker DE, Kramer AE, et al.: The SWAL-QOL outcomes tool for oropharyngeal dysphagia in adults: I. Conceptual foundation and item development. Dysphagia 2000, 15: McHorney CA, Bricker DE, Robbins J, et al.: The SWAL-QOL outcomes tool for otopharyngeal dysphagia in adults: II. Item reduction and preliminary scaling. Dysphagia 2000, 15: McHorney CA, Robbins J, Lomax K, et al.: The SWAL-QOL and SWAL-CARE outcomes tool for oropharyngeal dysphagia in adults: III. documentation of reliability and validity. Dysphagia 2002, 17: Chen AY, Frankowski R, Bishop-Leone J, et al.: The development and validation of a dysphagia-specific quality of life questionnaire for patients with head and neck cancer. Arch Otolaryngol Head Neck Surg 2001, 127: Rogers SN, Laher SH, Overend L, Lowe D, et al.: Importance-rating using the University of Washington Quality of Life Questionnaire in patients treated by primary surgery for oral and oro-pharyngeal cancer. J Craniomaxillofac Surg 2002, 30: