A rare case report of an solitary neurofibroma in postcricoid region of hypopharynx.

RATIONALE: Postcricoid neurofibroma is an extremely rare hypopharynx tumor that can be challenging in both diagnosis and treatment. This case sheds light on the possibility of treatment with transoral microsurgery before pursuing open cervical incisions. PATIENT CONCERNS: : A 43-year-old man presented with a four months history of a persistent foreign body sensation and mild dysphagia. Indirect and direct laryngoscopy at admission revealed a round and smooth submucosal mass in the postcricoid region. DIAGNOSIS: A laryngeal enhanced computed tomography and laryngoscopy suggested that the tumor located in hypopharynx, with clear boundary and slightly strengthened edge. A supporting laryngoscopy surgery was performed under general anesthesia and a biopsy confirmed solitary neurofibroma of the postcricoid region. INTERVENTIONS: The tumor was successfully resected en bloc transorally through supporting laryngoscope, and obviated the need for open cervical surgery and tracheostomy. OUTCOMES: The patient recovered well without any intraoperative or postoperative complication and was discharged from hospital 2 days after surgery. There was no recurrence after 6 months follow-up. LESSONS: Postcricoid neurofibroma is an extremely rare hypopharynx tumor that can be diagnostically challenging. To the best of our knowledge, this is the first case reported of solitary neurofibroma originating from the postcricoid region of the hypopharynx and was surgically removed with transoral surgery through supporting laryngoscope.

Cricoarytenoid Joint Ankylosis: Classification and Transoral Laser Microsurgical Treatment.

OBJECTIVE: This study aimed to describe a graduated approach for effective transoral mobilization of cricoarytenoid joint ankylosis (CJA) in the context of the Bogdasarian system of classifying posterior glottic web-based stenosis (PGWS). STUDY DESIGN: This is a retrospective cohort study through data from medical records and operative notes. A consecutive series of 23 patients who underwent reconstructive transoral laser microsurgery for PGWS with a significant degree of CJA (Bogdasarian grade III-IV) was included in the study. METHODS: Techniques necessary to remobilize their cricoarytenoid joints were reviewed in the context of the extent of scar tissue found. RESULTS: Arytenoids with CJA were successfully mobilized by resection of the fused portion of the cricoid and arytenoid cartilages achieving respiratory improvements as well as decannulation of tracheostomy-dependent patients. The majority (83%) of patient's voices improved. All patients tolerated a full diet after the procedures. Cases with Bogdasarian grade III PGWS with minor unilateral fixation should be classified as IIIa. If the fixation is severe, the case should be classified as a grade IIIb. Grade IVa would indicate that both sides were mildly to moderately ankylosed, and grade IVb involves ankylosis of both joints with subtotal or complete fusion of at least one; it presents the greatest surgical challenge. CONCLUSION: We provided effective transoral techniques for the re-mobilization of cricoarytenoid joint, along with a classification of CJA that aims to standardize the severity of disease in the context of the existing and widely accepted Bogdasarian scale.

Cricoid Pressure During Induction for Tracheal Intubation in Critically Ill Children: A Report From National Emergency Airway Registry for Children.

OBJECTIVES: Cricoid pressure is often used to prevent regurgitation during induction and mask ventilation prior to high-risk tracheal intubation in critically ill children. Clinical data in children showing benefit are limited. Our objective was to evaluate the association between cricoid pressure use and the occurrence of regurgitation during tracheal intubation for critically ill children in PICU. DESIGN: A retrospective cohort study of a multicenter pediatric airway quality improvement registry. SETTINGS: Thirty-five PICUs within general and children's hospitals (29 in the United States, three in Canada, one in Japan, one in Singapore, and one in New Zealand). PATIENTS: Children (< 18 yr) with initial tracheal intubation using direct laryngoscopy in PICUs between July 2010 and December 2015. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: Multivariable logistic regression analysis was used to evaluate the association between cricoid pressure use and the occurrence of regurgitation while adjusting for underlying differences in patient and clinical care factors. Of 7,825 events, cricoid pressure was used in 1,819 (23%). Regurgitation was reported in 106 of 7,825 (1.4%) and clinical aspiration in 51 of 7,825 (0.7%). Regurgitation was reported in 35 of 1,819 (1.9%) with cricoid pressure, and 71 of 6,006 (1.2%) without cricoid pressure (unadjusted odds ratio, 1.64; 95% CI, 1.09-2.47; p = 0.018). On multivariable analysis, cricoid pressure was not associated with the occurrence of regurgitation after adjusting for patient, practice, and known regurgitation risk factors (adjusted odds ratio, 1.57; 95% CI, 0.99-2.47; p = 0.054). A sensitivity analysis in propensity score-matched cohorts showed cricoid pressure was associated with a higher regurgitation rate (adjusted odds ratio, 1.01; 95% CI, 1.00-1.02; p = 0.036). CONCLUSIONS: Cricoid pressure during induction and mask ventilation before tracheal intubation in the current ICU practice was not associated with a lower regurgitation rate after adjusting for previously reported confounders. Further studies are needed to determine whether cricoid pressure for specific indication with proper maneuver would be effective in reducing regurgitation events.

Diagnostic and prognostic contribution of laryngeal electromyography in unilateral vocal-fold immobility in adults.

OBJECTIVES: To study the diagnostic and prognostic contribution of laryngeal electromyography in unilateral vocal-fold immobility in adults. MATERIAL AND METHODS: A retrospective study included patients with unilateral vocal-fold immobility undergoing laryngeal electromyography between 2007 and 2015. Neurogenic, normal or myogenic findings were compared to the clinical aspect. Prognosis for recovery was assessed from motor unit potentials on laryngeal electromyography, and compared to subsequent progress on laryngoscopy. RESULTS: Sixty-three patients (mean age, 59 years) were initially included; 2 were subsequently excluded from analysis. Mean time from onset of immobility to laryngeal electromyography was 7 months. 85% of the 61 patients showed neurogenic findings, indicating neural lesion; 13% showed normal electromyography, indicating cricoarytenoid joint ankylosis; and 1 patient showed a myogenic pattern. Neurogenic cases were usually secondary to cervical surgery. Thirty-eight patients were followed up. In total, 75% of patients showing reinnervation potentials recovered. The positive predictive value of laryngeal electromyography was 69.2%. CONCLUSION: Laryngeal electromyography is effective in specifying the origin of unilateral vocal-fold immobility in adults. It also has a prognostic role, lack of reinnervation potentials being a possible indication for early medialization surgery.

Mechanical Modeling of the Human Cricoid Cartilage Using Computer-Aided Design: Applications in Airway Balloon Dilation Research.

OBJECTIVES: Balloon dilation is generally considered first-line treatment for airway stenosis. Some dilation systems utilize a compliant balloon that can conform around rigid structures. Others use a noncompliant balloon that does not conform, allowing for dilation of more rigid stenoses. We hypothesized that subglottic dilation with a noncompliant balloon increases the likelihood of fracture of the cricoid when compared to a compliant balloon. METHODS: Three fresh human cricoid cartilages were placed in a universal testing system to determine the expansile force necessary for cricoid fracture. Using these data, a 3D printer was used to construct a synthetic cricoid model possessing near identical physical characteristics to the human cricoid. Simulated dilation was then performed on the model using a compliant and a noncompliant balloon. RESULTS: Human cricoid fracture occurred at 97.25 N (SD = 8.34), and the synthetic cricoid model fractured at 100.10 N (SD = 7.32). Both balloons fractured the model in every replicate experiment. Mean balloon internal pressure at fracture was 7.67 ATM (SD = 1.21) for the compliant balloon and 11.34 ATM (SD = 1.29) for the noncompliant balloon. CONCLUSIONS: These data show that fracture of the cricoid is a valid concern in balloon dilation procedures where the balloon spans the subglottis. Furthermore, the hypothesis was rejected in that the compliant balloon system was at least as likely to fracture the cricoid model as the noncompliant.

Cricopharyngeal dysfunction: A systematic review comparing outcomes of dilatation, botulinum toxin injection, and myotomy.

OBJECTIVES: Cricopharyngeal dysfunction may lead to severe dysphagia and aspiration. The objective of this systematic review was to evaluate the existing studies on the effectiveness of myotomy, dilatation, and botulinum toxin (BoT) injection in the management of cricopharyngeal dysphagia. METHODS: PubMed and Web of Science databases were searched to identify eligible studies by using the terms "cricopharyngeal dysfunction," "cricopharyngeal myotomy," "cricopharyngeal botox," "cricopharyngeal dilation," and their combinations from 1990 to 2013. This was supplemented by hand-searching relevant articles. Eligible articles were independently assessed for quality by two authors. Statistical analysis was performed. RESULTS: The database search revealed 567 articles. Thirty-two articles met eligibility criteria and were further evaluated. The reported success rates of BoT injections was between 43% and 100% (mean = 76%), dilation 58% and 100% (mean = 81%), and myotomy 25% and 100% (mean = 75%). In logistic regression analysis of the patient-weighted averages, the 78% success rate with myotomy was significantly higher than the 69% success rate with BoT injections (P = .042), whereas the intermediate success rate of 73% with dilation was not significantly different from that of either myotomy (P = .37) or BoT (P = .42). There was a statistically significant difference between endoscopic and open myotomy success rates (P = .0025). Endoscopic myotomy had a higher success rate, with a 2.2 odds ratio. CONCLUSIONS: The success rate of myotomy is significantly higher than the success rate of BoT injections in cricopharyngeal dysfunction. Moreover, endoscopic myotomy was found to have a higher success rate compared to open myotomy.

Spontaneous MRSA postcricoid abscess: a case report and literature review.

Laryngeal abscesses are rare but potentially life-threatening infections due to potential airway obstruction. Most abscesses occur in the epiglottis or preepiglottic space as a sequela of acute supraglottitis. Abscesses in the posterior larynx are extremely rare and typically due to instrumentation or trauma. Appropriate workup and management of the airway are essential for optimizing outcomes in these patients. We present an interesting case and our management of a spontaneous posterior laryngeal abscess due to methicillin-resistant Staphlococcus aureus.

Laryngotracheal stenosis and restenosis. What has the influence on the final outcome?

The aim of this study is to analyze the impact of various parameters on the course and treatment outcome in patients with laryngotracheal stenosis and recurrent stenosis. Two groups of patients were compared: Group I included 29 patients with primary stenosis, and Group II included 22 patients with recurrent stenosis. The most frequent etiological factor for the development of stenosis was prolonged endotracheal intubation (79.3:77.3%), with subglottic-tracheal (44.8:45.5%) and tracheal (48.3:36.4%) localization being the most affected. Subglottic-tracheal stenosis was more common in men. There were no significant differences between the groups in regard to the grade of lumen obstruction and the length of the resected segment. In male patients, the length of the resected stenotic segment was significantly longer. Subglottic-tracheal stenoses were longer than tracheal ones. Various surgical procedures were performed, with additional management of recurrent laryngeal nerve paralysis, if necessary. Laryngotracheal reconstruction (LTR) with costal cartilage grafting (CCG) was statistically significantly more often performed in Group II, while cricotracheal resection (CTR) was more common in Group I. The incidence of complications in Group I was 24.1%, and in Group II it was 31.8%. Satisfactory airway lumen with undisturbed breathing was achieved in 93.1% of patients in Group I, and in 95.3% in Group II. Since the success rate was similar in both groups of the patients, it could be concluded that treatment outcome depends less on the factors associated with the stenosis, and more on adequate choice of surgical procedure and surgical team know-how.

Efficacy of large-diameter dilatation in cricopharyngeal dysfunction.

OBJECTIVES/HYPOTHESIS: To investigate patient outcomes with large-diameter bougienage in isolated cricopharyngeal dysfunction and understand how esophageal dilatation can be used as an effective diagnostic and therapeutic modality in treating dysphagia. STUDY DESIGN: Retrospective review. METHODS: A retrospective chart review was performed on 46 patients meeting the criteria for cricopharyngeal dysphagia from 2004 to 2008 presenting in the outpatient setting. Patients were treated with 60 French esophageal dilators. Outcomes were analyzed as a function of symptomatology, manometry, duration of benefit, and safety. RESULTS: Over the period reviewed, 59 dilatations were performed on 46 patients with cricopharyngeal dysfunction. Eight patients were dilated more than once. Four patients were lost to follow-up. The average starting Functional Outcome Swallowing Score (FOSS) was 2.07. Of the patients reviewed, 64.29% experienced an improvement in their FOSS with a median duration of 741 days. There were five minor complications and no major complications. CONCLUSIONS: In the largest series of esophageal dilatation for cricopharyngeal dysfunction in the literature, we found large-bore bougienage to have significant utility due to its efficacy, ease of use, and safety when compared to other modalities such as botulinum injection, balloon dilatation, and cricopharyngeal myotomy.

Use of intraoperative laryngeal electromyography to evaluate stridor in children with arthrogryposis.

OBJECTIVES: Arthrogryposis is a rare, congenital condition characterized by joint contractures of the extremities with muscle weakness and fibrosis. The otolaryngological manifestations of this disorder may include stridor, chronic aspiration, and Pierre Robin sequence, among others. Prior reports of vocal fold immobility associated with arthrogryposis have attributed it to recurrent laryngeal nerve paralysis, rather than to cricoarytenoid joint restriction. The objective of this study was to determine whether children with arthrogryposis and vocal fold immobility demonstrated laryngeal electromyography (L-EMG) findings consistent with recurrent laryngeal nerve paralysis or with cricoarytenoid joint restriction. METHODS: A retrospective, institutional chart review of children with otolaryngological manifestations of arthrogryposis was performed; 6 children were identified. Three patients had vocal fold immobility documented by flexible laryngoscopy. These 3 children were prospectively evaluated with direct laryngoscopy and intraoperative L-EMG. RESULTS: The 3 children with arthrogryposis and vocal fold dysfunction had laryngoscopy-confirmed vocal fold immobility or significant restriction of motion. The intraoperative L-EMG tracings obtained from all 3 patients demonstrated motor unit action potentials without evidence of denervation. CONCLUSIONS: This series, albeit small, suggests that the vocal fold dysfunction related to arthrogryposis may be attributable to cricoarytenoid joint restriction or poor laryngeal coordination, rather than to nerve paralysis, as originally postulated.

Effect of cricoid force on airway calibre in children: a bronchoscopic assessment.

BACKGROUND: Cricoid pressure or to be more exact cricoid force (CF) can cause airway obstruction and subsequent difficulty with airway management during an emergency induction. METHODS: We studied 30 children with an age range of 3 months to 15 yr who presented for routine bronchoscopy or other surgical procedures requiring tracheal intubation. We looked at the effect of CF on the calibre of the subglottic airway and objectively measured the force which caused 50% or greater distortion/compression of the subglottic airway. RESULTS: There was a linear relationship between both age and weight and CF. No patient suffered any adverse effects. Overall, the mean force required to compress the airway was 10.5 N. However, this force could be as low as 5 N in children <1 yr of age, and up to between 15 and 25 N in teenagers. CONCLUSIONS: Forces well below the recommended value of 30 N will cause significant compression/distortion of the airway in a child.

Endoscopic CO2 laser cricopharyngeal myotomy.

OBJECTIVES: Over the past 10 years, endoscopic cricopharyngeal myotomy laser surgery has been proposed as an alternative to transcervical cricopharyngeal myotomy. We will describe the technique and review the literature so that it may gain credence as a viable option for the treatment of cricopharyngeal achalasia. METHODS: A literature review of endoscopic and transcervical cricopharyngeal myotomy will be performed. The technical aspects of endoscopic cricopharyngeal myotomy will be presented and accompanied by intraoperative photographs, illustrations, and an online video demonstration. RESULTS: Endoscopic cricopharyngeal myotomy is a well-tolerated procedure with low morbidity and good outcomes. It can be performed by surgeons who are comfortable with transoral laryngopharyngeal laser surgery. CONCLUSIONS: Endoscopic cricopharyngeal myotomy is a viable alternative to classic transcervical cricopharyngeal myotomy with equivalent outcomes and comparable if not less morbidity.

On the development of idiopathic subglottic stenosis.

Idiopathic subglottic stenosis is a fibrotic narrowing of the airway at the level of the cricoid cartilage, which can result in severe dyspnea. There is an overwhelming female preponderance, and treatment usually involves dilation, tracheostomy or resection with reconstruction of the involved portion of the airway. The exact mechanism of action is unknown. Estrogen has been thought to play a role in the pathogenesis of this disease, but estrogen receptors have not been found in tissue specimens taken from afflicted individuals. A careful history taken from the patient often reveals a severe episode of coughing prior to the development of symptoms, and intraoperative examination can reveal impaction of the first tracheal ring within the lumen of the cricoid cartilage. Based on these observations, we surmise that an intermittent telescoping effect of the first tracheal ring within the lumen of the cricoid cartilage can lead to disruption of the local blood supply and trauma to the cricoid mucosa, with consequent mucosal edema, ischemia, and ultimately fibrosis. While estrogen has been shown to play a beneficial role in wound healing, abnormal wound healing may be potentiated by variations in estrogen receptor expression, and could also explain the female preponderance seen in this disease.

Effect of vascular endothelial growth factor on laryngeal wound healing in rabbits.

OBJECTIVE: Study the effects of vascular endothelial growth factor (VEGF) on laryngeal wound healing in a rabbit model. STUDY DESIGN: Prospective, randomized, blinded. METHODS: The anterior cricoid cartilage of 10 rabbits was split and a VEGF-soaked collagen sponge was sewn between the cut edges. In 10 control animals, the collagen sponge was soaked with phosphate-buffered saline solution. The larynx was harvested on day 10. The degree of epithelial closure, the degree of soft tissue closure, and the presence of inflammatory cells was graded. RESULTS: There was complete epithelial closure in the control group. There was a slightly higher, but not statistically significant, grade of soft tissue closure in the experimental group. The experimental group had a lower but not statistically significant acute inflammatory response score. CONCLUSIONS: The topical application of VEGF through an implanted collagen sponge to an anterior, subglottic incision in a rabbit has no significant effect on tracheal luminal epithelial closure, acute inflammatory response, or soft tissue repair at postsurgical day 10.

Age-related changes in human laryngeal nerves.

OBJECTIVES: We sought to perform a morphometric analysis of myelinated fibers from laryngeal nerves with the aim of verifying quantitative changes due to the aging process. METHODS: A 1-cm fragment was collected from the superior laryngeal nerves and recurrent laryngeal nerves from 12 cadavers during autopsy. The sample was divided in two groups: an adult group (aged <60 years) and an elderly group (aged > or =60 years). RESULTS: The total number of myelinated fibers from the superior laryngeal nerves was similar in both groups (adult group = 9017 +/- 1692, elderly group = 7918 +/- 1624; P = 0.79). The adult group had a higher total number of myelinated fibers in the recurrent laryngeal nerves than that of the elderly group (adult group = 3276 +/- 383, elderly group = 2381 +/- 669; P = 0.005), as well as a higher total number of fibers in the laryngeal nerves (both superior and recurrent) than the elderly group (P = 0.02). CONCLUSIONS: The adult group has a higher total number of myelinated fibers in the laryngeal nerves than the elderly group.

Cricopharyngeal myotomy normalizes the opening size of the upper esophageal sphincter in cricopharyngeal dysfunction.

OBJECTIVE: The development of a cricopharyngeal dysfunction is associated with a hypertonic cricopharyngeus (CP) muscle. Therefore, CP myotomy has been advocated by some authors to be an essential part of repair of this condition. However, little objective data exists to show that there is improvement in the upper esophageal sphincter (UES) after CP myotomy. This study assesses the impact of CP myotomy on UES opening. STUDY DESIGN: Prospective. METHODS: Twenty patients treated at a university tertiary care center for cricopharyngeal dysfunction between 1998 and 2003 were identified. All patients underwent CP myotomy with or without Zenker's diverticulectomy. These patients had videofluoroscopic swallow studies before and after repair. The values of UES opening for 3 mL boluses from pre- and postrepair studies were compared with each other as well as with normal controls. Sixty percent (12/20) of the patients had a Zenker's diverticulum. Of these 12 patients, 5 had undergone previous attempts at surgical correction. Cricopharyngeal myotomy by way of an external approach, with or without Zenker's diverticulectomy, was performed in all patients by the senior author. RESULTS: Before Zenker's diverticulectomy and CP myotomy, the mean UES opening (n = 20) for a 3 mL bolus was 0.30 cm +/- 0.17, which was 57% of the mean of 60 normal controls (0.52 cm +/- 0.15) (P < .001). After repair, the mean UES opening for the same bolus size improved to 0.51 cm +/- 0.16 (P < .0001). The UES opening size in patients who have undergone repair is comparable with that of the normal controls (P > .05). CONCLUSIONS: UES opening size in patients with cricopharyngeal dysfunction is 57% of the size in normal controls. CP myotomy helps to normalize the UES opening in cricopharyngeal dysfunction repair.

Structural characteristics of repair tissue of cricoid cartilage defects treated with recombinant human bone morphogenetic protein-2.

We examined the structural characteristics of repair tissue induced by recombinant human bone morphogenetic protein-2 in a rabbit model of laryngotracheal reconstruction. Twenty-four New Zealand White rabbits were randomly divided into four groups of six rabbits. Two groups were treated with recombinant human bone morphogenetic protein-2 delivered on an absorbable collagen sponge, while two groups were used as controls. Rabbits were euthanized at 1 and 4 weeks after surgery. The larynx was removed, fixed, and sectioned. The sections were stained with hematoxylin-eosin, safranine O/fast green, and immunostained with an antibody for tissue inhibitor of metalloproteinases-1. In rabbits treated with bone morphogenetic protein-2, the defects were filled with new cartilage and bone at 4 weeks after surgery. There were no discontinuities or gaps at the margins of the cartilage defects. Proteoglycans were synthesized in new cartilage in rabbits treated with bone morphogenetic protein-2, and were present 4 weeks after surgery. The general aspects of the vascular pattern and the pattern of tissue inhibitor of metalloproteinases-1 expression were similar in control and treated rabbits, both 1 week and 4 weeks after surgery. The repair tissue induced by recombinant human bone morphogenetic protein-2 consisted of new cartilage and bone perfectly integrated with host tissue at the site of the cricoid cartilage defects. This new cartilage was able to mature and produce proteoglycans.

Endoscopic CO2 laser-assisted surgery for cricopharyngeal dysfunction.

Endoscopic cricopharyngeal myotomy was performed on 29 patients with dysphagia from failed relaxation of the cricopharyngeal muscle. The patient outcome was retrospectively evaluated. The average age at the time of treatment was 62 years (range: 38-81 years), and the mean follow-up was 18 months (range:1-36 months). The procedure was the first to be performed in all except four of the patients. Preoperative and postoperative assessments included videofluoroscopic and flexible endoscopic evaluations of the swallow as well as patients' subjective ratings for dysphagia and aspiration. These investigations and self-assessments were rated from 0 (poor or abnormal) to 4 (good or normal). Surgical procedures were performed under general anesthesia. Using the diverticuloscope, the posterior portion of the cricopharyngeal muscle was exposed and CO2 laser sectioned. The wound was then covered with fibrin glue. Patients were parenterally fed for 72 h. Postoperative videofluoroscopy showed the absence of leakage, and all patients resumed oral intake on day 2. The median self-rating score improved from 1 to 4 for dysphagia and from 3 to 4 for aspiration. The outcome of the flexible endoscopic evaluation of swallow improved from 2 to 4 and videofluoroscopy improved from 2 to 4. No surgical complication occurred. Endoscopic CO2 laser-assisted surgery is an effective and safe alternative for the treatment of cricopharyngeal dysmotility.

Botulinum toxin in the treatment of cricopharyngeal dysphagia.

Dysphagia is a common symptom in various neurological disorders affecting pharyngeal functions. Cricopharyngeal dysfunction is one of the major findings in these patients. The most effective treatment for restoring normal swallowing function in persistent cricopharyngeal dysfunction is cricopharyngeal myotomy, especially when mechanical obstruction or a well-localized neuromuscular dysfunction, such as a cricopharyngeal muscle spasm, is present. However, when there is a more diffuse neurological disorder present the results of surgery are more disappointing. In unclear cases, or in patients with temporary problems, no good method other than swallowing training, bougienage, and tube feeding are available. During the past decade, botulinum toxin has been found to be of therapeutic value in the treatment of a variety of neurological disorders associated with inappropriate muscular contractions such as torticollis and spasmodic dysphonia. Recently, injections of botulinum toxin in patients with cricopharyngeal muscle dysfunction have been reported to result in marked relief of dysphagia. In this article we describe our experiences with botulinum toxin injections to treat four patients suffering from deglutition problems and cricopharyngeal dysphagia of different origins. Botulinum toxin was injected into the cricopharyngeus muscle that was identified by endoscopy under general anesthesia. In this study, no major side effects were observed. Three patients obtained a significant improvement of esophageal symptoms after the first injection. The treatment had limited effect in one patient who had reflux disease and only slight cricopharyngeus dysfunction.