Esophageal Dysphagia

TITLE: Esophagea <= span class=3DSpellE>Dysphagia
SOURCE: Grand Rounds Presentation, UTMB, Dept. of Otolaryngology
DATE: February 6, 2008
RESIDENT PHYSICIAN: John P. Font,= M.D.
FACULTY PHYSICIAN: Michael Underbrink, M.D., M.B.A.
SERIES EDITORS: Francis B. Quinn, Jr., MD

"This material was prepared by resident physicians in partial fulfillment of educational requirements established for the Postgraduate Training Program = of the UTMB Department of Otolaryngology/Head and Neck Surgery and was not intended for clinical use in its present form. It was prepared for the purp= ose of stimulating group discussion in a conference setting. No warranties, eit= her express or implied, are made with respect to its accuracy, completeness, or timeliness. The material does not necessarily reflect the current or past opinions of members of the UTMB faculty and should not be used for purposes= of diagnosis or treatment without consulting appropriate literature sources and informed professional opinion."

Anatomy

The esophagus starts at the junction of the infe= rior pharyngeal constrictor and cricopharyngeus. The= esophagus is about 18 to 26 cm in length ending at the at the distal margin of the lo= wer esophageal sphincter (LES). The UES is form by inferior pharyngeal constric= tor and the cricopharyngeus. The LES is a thickened seg= ment of circular smooth muscle that lies within the diaphragmatic hiatus. Struct= ures extrinsic to the esophagus make indentations which are noted during endoscopy. These include the anterior body of C7 (worsen by osteophytes), tr= achea anteriorly, the arch of the aorta, the left mainstem bronchus, and the diaphragmatic hiatus.

The esophageal wall is composed of four layers: = mucosa, submucosa, muscularis propria, and outermost adventitia. The esophagus has = no serosa. The esophageal mucosa is lined by a nonkeratinized stratified squamo= us epithelium. The stomach is lined with columnar epithelium. This junction of the squamous epithelium and columnar epithelium (squamocolumnar junction) is called the Z-line. The abnormal cephalad<= /span> movement of this junction is referred to as Barrett’s esophagus.

The submucosa contai= ns blood vessels, lymphatic channels, neurons of Meissner's plexus, and esophageal glands. These glands produce and secrete lubricant, mucus, and factors such as bicarbonate and epidermal growth factor that are important for epithelial defense and repair. The muscu= laris propria consists of both skeletal and smooth mu= scle. The proximal one third is skeletal muscle, the middle third is mixed, and t= he distal portion is smooth muscle. The muscles are arranged into inner circular and outer longitudinal layers.

The esophageal wall is innervated by both parasympathetic and sympathetic nerves. The parasympat= hetics regulate peristalsis through the vagus nerve. N= eural innervation of the esophagus is from the myenteric (Auerbach's ple= xus) located between the two muscle layers and from Meissne= r's plexus located in the submucosa. The myenteric plexus is responsible for esophageal perist= alsis. The Meissner's plexus is the site of afferent s= ensory input. Excitatory stimulation from acetylcholine mediates contraction of bo= th the longitudinal and circular muscle layers. Inhibitory neurons predominant= ly affect the circular muscle layer via nitric oxide. Excitatory stimulation f= rom acetylcholine has its largest effect proximally, whereas inhibitory effect = of nitric oxide is seen distally. Pain sensation arising from the esophagus overlaps with those of the heart and respiratory system, in clinical practi= ce it may be difficult to discern the organ of origin for some chest pain syndromes.

The arterial and venous blood supply to the esop= hagus is segmental. The upper esophagus is supplied by branches of the superior a= nd inferior thyroid arteries. The mid-esophagus is supplied by branches of the bronchial and right intercostal arteries and descending aorta. The distal esophagus by branches of the left gastric, left inferior phrenic, and sple= nic arteries. The venous drainage of the upper esophagus is through the superior vena cava, the mid-esophagus through the azygous veins, and the distal esophagus through the portal vein by means of the left and short gastric veins.

The lymphatic system of the esophagus is also segmental; the upper esophagus drains to the deep cervical nodes, the mid-esophagus to the mediastinal nodes, and the distal esophagus to the celiac and gastric nodes. These lymphatic systems a= re also interconnected by numerous channels, accounting for the spread of most esophageal cancers beyond the region at the time of their discovery.

Functionally, the esophagus c= an be divided into three zones: the UES, the esophageal body and the LES. The esophageal phase of swallowing starts with the transfer of the food bolus through the UES. As the UES closes, a progressive circular contracti= on begins in the upper esophagus and proceeds distally along the esophageal bo= dy. The LES relaxes as the UES closes allowing the unopposed force of the esophageal body peristalsis to propel the bolus into the gastric bed. The pressures may vary with the consistency of the bolus itself. The LES subsequently closes with a prolonged contraction, preventing movement back = into the esophagus.

Secondary peristalsis is a progressive contracti= on in the esophageal body that is induced by stimulation of sensory receptors activated by residual food bolus or the refluxed gastric contents. This beg= ins approximately at or abo= ve the level of the stimulus and resembles primary peristalsis. Its function is to clear the esophagus from food contents poorly cleared by the primary peristalsis and to push refluxed gastric contents back into the stomach.

Dysphagia

Dysphagia refers to = the sensation that food is hindered in its passage from the mouth to the stomac= h. Most patients complain that food “sticks,” “hangs up,R= 21; or “stops,” or they feel that the food “just won't go down right.” It may be anatomically classified into two separate clinical categories: oropharyngeal and esophageal. Psych= iatric disorders can amplify this symptom.

As part of the history it is important to clarif= y the origin of symptoms of esophageal dysphagia. Thr= ee questions are crucial:

(1) What types of food or liquid cause sympt= oms?
(2) Is the dysphagia intermittent or progressiv= e?
(3) Does the patient have heartburn?

Patients with primarily solid food dysphagia typically have a structural lesion, such as a peptic stricture, ring, or malignancy. Esophageal rings tend to cause intermittent solid food dysphagia whereas strictures and cancer cause progres= sive dysphagia. Those with both solid and liquid dysphagia are more likely to have a motility disorder= like achalasia or scleroderma. The site at which a patient localized dysphagia is of limited value. Weight= loss in a patient with dysphagia is an indicator of = the significance and duration of the disease.&= nbsp; Dietary changes in response to the dysphagia give insight into the nature and severity of disease.

Dysphagia must be distinguished from odynophagia, which refers to= pain caused by swallowing. This important symptom is clearly indicative of a pharyngeal or esophageal problem. Most often this is an inflammatory condit= ion of the esophagus such as erosive esophagitis, pill-induced esophagitis, or infectious esophagitis.

Endoscopy is the tec= hnique of choice for the evaluation of the mucosa of the esophagus and detection of structural abnormalities. Rigid esophagoscopy h= as long been an established method for evaluation and treatment of esophageal disorders commonly used by otolaryngologists. This procedure requires general anesthesia and provides a means to examine the full extent of the esophagus, however the view is not magnified, the esophagus is not distended, and the procedure caries both the risks of general anesthesia and the rigid esophagoscopy. Conventional flexible esophagoscopy pass= ed transorally has used scopes with diameters approachin= g 1cm which provide a magnified view, suction, irrigation, and biopsy ports. The = use of these scopes usually requires intravenous sedation. In the past decade manufacturers h= ave produced flexible esophagoscopes with diameters around 5mm with digital video chip technology. These scopes provide a quality ima= ge and include the ability to suction, irrigate and biopsy. The smaller size allows their pass= age through the nasal cavity and the use of topical anesthesia. Without the need for intravenous sedation transforming this method into a easily performed clinic procedure = and the patient can returned to work after the appointment. Another benefit of flexible esophagoscopy is that it allows the insufflation of air to distend the esophagus and more easily see all of the mucosa.

The transnasal-esophagoscop= e procedure starts with the application of topical anesthesia to both the nas= al and oral cavity. The scope was advanced through the nose into the oropharynx. Velopharyngeal closure, anatomy of the base of the to= ngue and hypopharynx, vocal cord motion, status of t= he pharyngeal musculature, and patient’s ability to manage their own secretions was noted. With the scope above the cricopharyngeus the patient was= asked to burp or swallow to allow passage of the scope. The scope was then advanced to the= gastroesophageal junction taking care to note any abnormalities. The squamocolumnar junction (SCM= ) can be recognized by the irregular Z line, demarcating the interface bet= ween the light pink esophageal squamous mucosa and t= he red columnar gastric mucosa. The GEJ is defined by the proximal margin of the gastric folds. Although the SCM and GEJ are normally located at the same le= vel, the two are not synonymous. In patients with Barrett's esophagus, the SCM is more proximal in the esophagus than the GEJ. Endoscopy can also be used= to diagnose the presence of hiatal hernia.

Aviv et al in 2001 reported their experience wit= h transnasal esophagoscopy.= They performed exams on 14 consecutive patients with dyspha= gia. Patients were asked to avoid aspir= in, aspirin-like compounds, and vitamin E for two weeks prior to the procedure = in case biopsies were necessary. The exams were performed in the otolaryngologist’s office with the patien= t in a standard examining chair. A= 4.9mm outer diameter endoscope was used. Biopsies were then performed if necessary. They had patients rate the discomf= ort of the exam on a scale from one to ten (with one being no discomfort). Overall tolerance was rated as a 2= by the patients. All patients st= ated they would be willing to repeat transnasal esophagoscopy if recommended by their physician. Auth= ors from the Department of Otolaryngology at Wake Forest University have pub= lished several articles on their experience with transnasal esophagoscopy. = Postma et al in 2005 published their review of 711 consecutive patients examined with transnasal <= span class=3DSpellE>esophagoscopy. They used a spray combination of 0.05%= oxymetazoline and 4% lidocaine in the nasal cavity. If biopsy or a longer procedure is required, one Tessalon Perle is used. Seventeen of 711 procedures (3%) w= ere terminated due to a tight nasal vault and 2 due to a self-limited vasovagal response. 100 of the patients were included= in a prior report. Of the 592 comp= leted exams in the newest series of patients, there was a 50% incidence of significant findings.

Esophageal manometry= is a diagnostic test that measures intraluminal pres= sures and coordination of the pressure activity of the three functional regions of the esophagus: the LES, esophageal body, and the UES. Manometry uses a catheter that measures pressures at various intervals along the length of= the esophagus. With each swallow,= data on strength, timing, and sequencing of pressure events are obtained. The advantage of the study is that= it is an actual test of pressure wave physiology. The disadvantages of the study are= that it is not widely available, cannot diagnose visible lesions, is unpleasant,= and is a technically demanding study to perform. For these reasons this study is ra= rely used except in cases where elevated intraluminal pre= ssures must be followed (e.g. achalasia). The study may be indicated for pat= ients who need recurrent intraluminal pressure assess= ment for achalasia or diffuse esophageal spasm.

The barium esophagram involves the use of a cup of liquid barium that is swallowed, then followed fluoroscopically to the stomach. Because the study is documented only on plain film, it is not consid= ered a dynamic swallow study. The = air contrast esophagram uses effervescent granules followed by administration of barium to provide better anatomic detail. The advantages of the study are th= at it is widely available, and with air contrast it provides better anatomic deta= il. The disadvantages are that the stu= dy involves radiation exposure, the logistics are difficult in bedridden patie= nts, and the study is not a dynamic one so it cannot adequately detect dynamic dysfunction. The study is ind= icated in patients in whom structural disorders are suspected (e.g. dysphagia to solid foods and not to liquids) because = of its relatively good level of anatomic detail.

Videofluoroesophagography is the procedure of choice as it allows a frame-by-frame evaluation of the rap= id sequence of events involved in transfer of the bolus from the mouth to the esophagus. Endoscopic examination is considered mandatory in all patients w= ith esophageal dysphagia. However, contrast esophagography may also be helpful; it can provide guidance for endoscopy that is anticipa= ted to be difficult (e.g., a patient with a complex stricture), suggest a disturbance in motility, and occasionally detect subtle stenoses that are not appreciated on endoscopy (the scope diameter is typically 10 m= m or less, whereas some symptomatic strictures can be considerably wider).

Dysphagia evaluation algorithm

Cummings: Otolaryngology: Head & Neck Surgery, 4th ed

Achalasia

Achalasia is a esoph= ageal motility disorder cause by loss of postganglionic inhibitory neurons of the= myenteric plexus leading to insufficient LES relaxati= on and loss of esophageal peristalsis. The symptoms of achala= sia include dysphagia for solids and liquid, regurgitation, and chest pain.

If achalasia is susp= ected, a barium esophagram with fluoroscopy is the best initial diagnostic study. This test will reveal a dilation of the proximal esophagus with loss of primary peristalsis in the distal two thirds of the esophagus. There is a smooth tapering of the lower esophagus leading to the closed LES, resembling a bird's beak. Esophageal manom= etry will confirm increased intraluminal pressure al= ong the LES with loss of peristaltic wave along the distal esophagus. About 70%= to 80% of patients have incomplete LES relaxation with swallows. Endoscopy sho= uld be performed to rule out a distal malignant esophageal stricture. The two m= ost effective treatments are graded pneumatic dilation and surgical myotomy. All patients considered for pneumatic dilati= on should be surgical candidates because the procedure is associated with a 2%= to 5% risk of perforation. Studies to date indicate good-to-excellent relief of symptoms in 50% to 93% of patients using the graded dilators. Myotomies are increasingly being performed by laparos= copy with a good-to-excellent response rate of 80% to 94%. For patients who are = at high risk for pneumatic dilation or surgery, endoscopic injection of the LES with botulinum toxin (Botox) or pharmacologic treatment with nitrates or calcium-channel blockers may be acceptable alternatives.

Diffuse esophageal spasm (DES)

Diffuse esophageal spasm (DES) is characterized = by simultaneous and repetitive contractions in the esophageal body on = manometric studies. LES relaxation is also normal in DES. The classic finding on esophagogram is the "corkscrew" esophagus. = Patients with DES may present with chest pain or dysphagia. The treatment of DES consists of medications that relax the esophagus, such= as nitrates and calcium-channel blockers, but is usually not completely effect= ive. Secondary motility disorders are commonly a result of systemic conditions. = The most common condition affecting esophageal motility is scleroderma.

Strictures

An esophageal stricture is defined as any loss of lumen area within the esophagus. The normal esophagus measures 20 mm in diameter. The predominant clinical symptom of strictures is dysphagia, which is usually most prevalent when the lumen diameter is less than 15 mm.= The most common cause of strictures is acid/peptic cause accounting for the majority of cases (60%–70%). The treatment of benign stricture diseas= e is esophageal dilation. Tight or complex strictures such as those less than 10= mm in diameter or greater than 2 cm in length are best managed with wire-guide= d dilation under fluoroscopic and endoscopic control. Simple strictures can be dilated with Maloney dilators that are passed orally. Esophageal dilation is perfor= med progressively over weeks to months with a gradual increase in the diameters= of the dilators. Most patients have relief of dysphagia after dilation to a diameter of 40 to 54 French or 13 to 17 mm with no requirement for maintenance dilations. Those with radiation-induced or malignant strictures are at higher risk of perforation. To minimize the ris= k of perforation, the "rule of threes" applies. That is, no more than three sequential dilators should be performed per session. Refractory strictures can be treated endoscopically with injection of triamcinolone into the stricture i= n all four quadrants prior to dilation. More recently, endos= copically placed temporary nonmetallic expandable stents (Polyfl= ex) were effective in the treatment of refractory benign strictures.

RINGS AND WEBS

Esophageal rings and webs are common findings on= upper endoscopy, and many are asymptomatic. Symptoms can include intermittent sol= id food dysphagia, aspiration, and regurgitation. = Rings are circumferential, can consist of mucosa or muscle, and most commonly occ= ur in the distal esophagus. Esophageal webs occupy only part of the esophageal lumen, are always mucosal, and are usually located in the proximal esophagu= s. Barium radiography is the most sensitive test to diagnose esophageal webs. = Endoscopic dilation is usually effective in the management of these patients. Cervical webs are associated with carcinoma and warrant endoscopic evaluation and biopsy. Schatzki's ring occurs at the GEJ at the distal margin of the LES and is the most common cause of intermittent solid food dysphagia and food impaction. Some authors believe the rings are congenital lesions, whereas others suspect a role for GERD.

Dysphagia lusoria

Dysphagia lusoria is the term given for symptoms arising from vascular compression of the esophagus by an aberrant right subclavian artery. The right subclavian artery in this circumstance arises from the left side of the aortic arch and courses from = the lower left to the upper right side posterior to the esophagus. Typically, t= he diagnosis is established by barium esophagogram, which shows the characteristic pencil-like indentation at the level of the third and fourth thoracic vertebrae. Confirmation is by CT, MRI, arteriography, or EUS. During endoscopy the right rad= ial pulse may diminish or disappear from instrumental compression of the right = subclavian artery. Symptoms usually respond to simple modification of the diet to meals of soft consistency and small size. =

= Gastroesophageal Reflux Disease= <= /span>

GERD is recognized in about 10-15% of the population. The disease does not typically cau= se dysphagia, so other causes should be explored. The cause of GERD is related to incompetence of the lower esophageal sphincter. Regurgitation of stomach contents = may cause sensation of subxyphoid pressure. Severe disease may lead to strictu= re formation, Barrett's esophagus, and increased risk of esophageal cancer. Radiography shows evidence of lower esophageal sphincter incompetence or sliding hiatal hernia in 1/3 of patients. In= direct laryngoscopy may show inte= rarytenoid erythema or edema. Manometry shows decreased lower esophageal sphincter tone. The gold stan= dard for diagnosis is the 24 hour pH probe.&nbs= p; Treatment is with anti-reflux medications such as H₂ bloc= kers and proton pump inhibitors along with life-style modifications.

Ambulatory 24-hour esophageal pH monitoring is an important tool in the diagnosis and management of GERD. Esophageal pH monitoring can detect and quantify gastroesophageal reflux and correlate symptoms temporally with reflux. The Bravo pH p= robe is a catheter-free monitoring system in which a pH monitoring probe approximately the size of a medication capsule is placed endoscopically.

Endoscopy is the tec= hnique of choice to evaluate the mucosa in patients with symptoms of GERD. Reflux = esophagitis is present when erosions or ulcerations a= re present at the SCM. There are many grading systems to characterize the severity of = esophagitis, the most common of which is the Los Angeles classi= fication.

The goals of treatment in GERD are to relieve symptoms, heal esophagitis, prevent recurrence = of symptoms, and prevent complications. A variety of lifestyle modifications a= re recommended in the treatment of GERD. These include avoidance of precipitat= ing foods (fatty foods, alcohol, caffeine), avoidance of r= ecumbency for 3 hours postprandially, elevation of the he= ad of the bed, smoking cessation, and weight loss. The cornerstone of GERD therap= y is the administration of agents that decrease gastric acid secretion, such as = H₂ blockers and proton pump inhibitors, thereby decreasing esophageal acid exp= osure. Treatment is with anti-reflux medications along with life-style modificatio= ns.

Barrett's esophagus is a potentially serious complication of long-standing GERD. Barrett's esophagus is present when the normal stratified squamous epithelium of the di= stal esophagus is replaced by intestinal columnar metaplasi= a. It is the most significant outcome of chronic GERD and predisposes patients= to the development of esophageal adenocarcinoma.

Malignant Stricture

Approximately 12,000 cases of esophageal carcino= ma occur in the United = States each year. Squamous cell carcinoma (SCC) is typ= ically a disease of black males and is associated with alcohol and tobacco abuse. Persons with a past history of caustic esophageal injury are also clearly at increased risk. Other conditions including achalasia, Plummer-Vinson syndrome, ptyalosis, and a history of head and = neck SCC may also confer increased risk. Esophageal dysplasia and SCC have also = been associated with human papillomavirus. On the ot= her hand, adenocarcinoma is predominantly a disease= of white males and has a well-documented association with GERD and Barrett's esophagus. Malignant obstruction because of esophageal carcinoma is a late presentation and carries a poor prognosis. Dysphagia is rapidly progressive. Tissue diagnosis can be made by endoscopy with muco= sal biopsy. Evaluation includes staging of the disease with computed tomography= and endoscopic ultrasound.

Cricopharyngeal Achalasia

A prominent cricopharyngeus= can cause dysphagia by failure of adequate open= ing of the pharyngoesophageal segment. This failure to open occurs second= ary to failure of pharyngeal and laryngeal elevation during swallowing, abnormal <= span class=3DSpellE>cricopharyngeal contraction, or inflammatory (e.g. gastroesophageal reflux disease, GERD) or neoplastic process.&= nbsp; Symptoms range from a "globus" sensation to significant dysphagia with pooling= of secretions and aspiration. Me= dical therapy includes treatment of GERD and Botox injection into the cricopharyngeus for temporary relief. If Botox works to correct dysphagia, cricopharyngeal myotomy may provide more permanent relief. In this somewhat controversial procedure, a careful releasing scalpel incision is made in the cricopharyngeal muscle avoiding mucosal damage. In properly chosen patients, this = procedure has a high success rate. Pati= ents with clear signs of cricopharyngeal spasm/hyper= trophy on radiology and manometry are most likely to benefit.

Zenker's Diverticulum

The Zenker's diverticulum is an acquired mucosal herniation through a posterior portion of the cricopharyngeus in an area of congenital weakness in the muscle known as Killian's dehiscence. Symptoms caused b= y the diverticulum include coughing up undigested food, aspiration, and chronic mucus production. Small diverticula can be treated by cr= icopharyngeal myotomy alone.= Larger diverticula require dissection of= f of the rest of the esophagus and transection with = the defect sutured in layers. Diverticulopexy, or suspension of the diverticulum vertically in pre-vertebral fascia is used to shorten the procedure and red= uce risk in high risk elderly patients. Endoscopic techniques use a variation of the Van Overbeek's diverticuloscope and the CO₂ laser to perform the diverticulotomy. The GIA stapler can also be used to divide and secure the pouch endoscopically.

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