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level: Esophagus

Questions and Answers List

level questions: Esophagus

QuestionAnswer
How is anatomy of esophagus?• Is a hollow tube of muscle 25 -30 cm • Begins at C6 and ends at T11 • Is divided into 4 segments : - Pharyngoesophageal - Cervical - Thoracic - Abdominal • Has 3 distinct area of narrowing (Cervical 14mm, bronchoaortic 16mm, diaphragmatic 18mm)
How is histology of esophagus?• Mucosa: consists of squamous epithelium except for the distal 1–2 cm, which is columnar epithelium. • Submucosa (mucous gland, blood vessels, Meissner neural plexus, extensive lymphatic network). • Muscularis propria: inner circular layer and outer longitudinal layer with septal connective tissue in between (Auerbach plexus). upper 1/3 is striated muscle whereas the lower 2/3 is smooth muscle. • Loose fibroalveolar adventitia (instead of a serosal layer, which is absent in the esophagus).
How is esophagus vasculature?• I. Arteries : - Cervical esophagus: supplied by inferior thyroid artery - Thoracic esophagus: supplied by bronchial artery, direct esophageal branches from the aorta - abdominal esophagus: supplied by left gastric and inferior phrenic arteries. •II. Veins : - Cervical esophagus veins drain into the inferior thyroid veins - thoracic esophagus veins drain into azygos and hemiazygos veins - abdominal esophagus veins drain into the left gastric veins. •III. Lymphatic drainage(to the nearest lymph nodes ): Upper esophageal lymphatics drain into the cervical or mediastinal nodes, whereas distal esophageal drainage is often to the celiac nodes.
How is esophagus innervation?• I. Sympathetic and parasympathetic systems : The esophagus is supplied by the pharyngeal plexus, vagus, upper and lower cervical sympathetic, and splanchnic nerves. • II. Auerbach (myenteric) and Meissner (submucosal) plexuses : influence esophageal motility
How is physiology of esophagus UES?• I. Upper esophageal sphincter (UES): This 3–5 cm high-pressure zone at the esophageal upper border is composed primarily of the cricopharyngeus muscle and relaxes during swallowing to allow food bolus passage. • II. Peristalsis : These wavelike movements in the central portion of the esophagus pass down the body of the esophagus and become stronger toward the lower portion. ➢Primary peristalsis: propels food down the esophagus ➢Secondary peristalsis: If a food bolus fails to progress, local stretch receptors trigger secondary peristalsis to move it.
How is physiology of esophagus LES?• III. Lower esophageal sphincter (LES): This 3–5-cm high-pressure zone at the esophageal lower portion functions to prevent gastroesophageal reflux (GER). No distinct sphincter muscle exists in this area, but manometry readily demonstrates the physiologic high-pressure zone. LES pressure is influenced by several actors and substances. • LES pressure increase: occurs with a protein meal, stomach alkalinization, gastrin, vasopressin, and cholinergic drugs • LES pressure decrease: occurs with secretin, nitroglycerine, glucagon, chocolate, fatty meals, and gastric acidification
How is general physiology of esophagus?1. Swallowing: initiated voluntarily continued reflexively 2. Pressure rises in hypopharynx (60mm) 3. A primary peristaltic wave follows 4. Secondary waves if retained food 5. LES: Relaxation within 2 sec. Then post-deglutition contraction This process takes some 9 sec
How is dx approach to esophageal diseases?• Upper gastrointestinal serries • Upper endoscopy • Endoscopic ultrasound • Ct scan • Esophageal manometry • Ambulatory 24-hour pH monitoring • Laparoscopy/thoracoscopy
What are esophageal motility disorders?• Achalasia • Diffuse esophageal spasm (DES) • Nutcracker esophagus • Esophageal diverticula ❖Zenker’s diverticulum ❖Epiphrenic diverticulum
What is achalasia?I. Pathophysiology: A. Absence of relaxation of the LES upon swallowing B. Simultaneous peristalsis in the esophageal body C. The intraluminal pressure increase and the body of the esophagus becomes dilated This due to neurogenic degeneration (autoimmune,genetic, infectious such as chagas disease caused by Trypanosoma cruzi) II. Symptoms : Dysphagia, regurgitation and weight loss. Respiratory symptoms caused by aspiration may be present. III. Diagnosis: A. Radiographic studies: typically reveal a dilated mid-esophagus with a “bird’s beak” appearance of the lower esophagus. B. Esophageal manometry: shows absence of peristalsis C. Esophagoscopy: Required to rule out cancer and to document the extent of esophagitis. Retained food is commonly found at endoscopy, and the LES may be difficult to traverse.
How is tx of achalasia?Non surgical (medications [CCB, Nitrates], hydrostatic dilatation [balloon dilates lower esophagus 60% relief, 10% second dilation, good long term results], Botulinum toxin [lower esophagus relaxation]) Surgical (Heller myotomy [relieves dysphagia 80-90%], Esophagectomy [if megaesophagus, failure of myotomy, reflux stricture undilated)
What is esophagocardiomyotomy?The esophagocardiomyotomy involves a complete incision of the circular muscle layer down to the mucosa, over a 7- 10 cm length distal to the left pulmonary vein usually combined with an anterior Dor fundoplication or a partial posterior Toupet fundoplication to ameliorate postoperative reflux
What is diffuse esophageal spasm?I. Pathophysiology: A. Characterized by strong nonperistaltic contractions B. Normal sphincteric relaxation and may be associated with GER II. Symptoms : may be spontaneous or may be induced by cold or hot liquids, stress, or carbonated beverages A. Chest pain: may be confused with angina pectoris B. Dysphagia: to liquids and solids
How is dx and tx of diffuse esophageal spasm?III. Diagnosis: A. Manometry: reveals high-amplitude simultaneous, multiphasic contractions with a normal sphincteric response to swallowing B. Contrast esophagram: may show a corkscrew appearance of the esophagus IV. Treatment: • Less satisfactory than in achalasia • Avoidance of “trigger” foods and drinks • Medical therapy: calcium channel blockers and smooth muscle relaxants (nitrates) • Endoscopic therapy: Botulinum toxin injected into the spastic segment may provide relief .
How is surgical tx of diffuse esophageal spasm?Surgical treatment • Thoracic esophagomyotomy including all circular muscle fibers from GE junction to above arch of Ao. • Inclusion of LES is controversial +/- antireflux • Success rate 50-60% • Indications: • Incapacitating DES (severe dysphagia, chest pain..) • Pulsion diverticulum Left lateral thoracotomy (between 6th and 7th ribs) Resection of an epiphrenic diverticulum and concomitant thoracic esophagomyotomy on the opposite wall. Secured under water seal to check for mucosal injury
What is nutcraker esophagus?• High-amplitude and duration peristaltic waves • Normal peristaltic sequence • Pressure in distal esophagus > 180 mmHg • Normal barium swallow (may be epiphrenic diverticulum) Treatment • Medical treatment: decreases strength of contractions only • Surgical treatment (myotomy): ❖Disappointing for chest pain ❖Relieves dysphagia (80%)
What is Zenckers diverticulum?• False diverticula consist only of mucosa rather than the entire esophageal wall. Arising above the UES (weak area ) Symptoms: dysphagia, halitosis, undigested food regurgitation, nocturnal aspiration, and recurrent aspiration pneumonia Diagnosis: • History and physical examination: raise the suspicion for Zenker diverticulum • Esophagram: Using water-soluble contrast can provide the diagnosis Treatment: • Cricopharyngeal myotomy: through a neck incision • Endoscopic stapler: This alternative to open surgery divides the diverticulum wall. • Diverticulopexy: Large diverticula may require myotomy combined with suspension of the diverticulum to prevent foodstuff from entering the residual sac
What is GERD?I. Etiology: Common—may affect up to 80% of the population to varying degrees. The normal barrier against reflux is provided by multiple actors. A. LES: normally provides a high-pressure zone B. Esophagogastric junction: normally rests within the abdominal cavity, and the positive intraabdominal pressure adds tone to the LES C. Angle of His (acute angle created between the junction of the lower esophagus and the cardia of the stomach): When the angle is disrupted, as with a hiatal hernia , gastric contents more easily traverse the LES. D. Esophageal motility: Some reflux is physiologic, but a normally functioning esophagus clears the refluxate. In cases of esophageal dysmotility, peristalsis is not adequate to clear the refluxed secretions.
What are sx and dx of GERD?• II. Symptoms : Substernal pain, heartburn, and regurgitation.Extraesophageal symptoms include sore throat, hoarse voice,halitosis, and dental caries. • III. Diagnosis: - History and physical - sophagoscopy: may reveal varying degrees of esophagitis - 24-hour pH probes: placed in the lower esophageal area to measure exposure of the esophagus to acid - Intraesophageal impedance monitoring: detects nonacid reflux
How is tx of GERD?IV. Treatment: A. Lifestyle modifications: weight loss, head-of-the-bed elevation B. Medical management 1. Acid-suppressing medications: include proton pump inhibitors and histamine receptor blockers 2. Baclofen (gamma-aminobutyric acid receptor agonist): may diminish transient LES relaxation and reduce symptoms in patients with refractory reflux
What are surgical tx of GERD?1. Indications (Evidence of severe esophageal injury (ulcer, strictures, Barrett’s..), Incomplete resolution while on medical treatment, Relapse while on medical treatment, Long duration of symptoms, Younger patients with persistent symptoms) 2. Antireflux operations: designed to mechanically restore the barrier to reflux and involve wrapping the lower esophagus with gastric fundus and restoring the distal esophagus to its original intra-abdominal position with the GEJ below the diaphragm. The following are most common. a. Nissen undoplication (360-degree wrap of the gastric fundus around the distal esophagus): usually performed laparoscopically with favorable results b. Belsey Mark IV operation (270-degree wrap): performed through a left thoracotomy c. Hill posterior gastropexy (includes a posterior 180-degree fundoplication, which is then anchored to the arcuate ligament of the diaphragm): emphasizes restoration of the LES to the intra-abdominal position
What are GERD complications?.
What is Barett's esophagus?• I. Definition: A. Intestinal metaplasia: occurs in the distal esophagus B. Columnar intestinal mucosa: replaces the normal squamous mucosa • II. Etiology: A. Caused by exposure of the lower esophagus to acid or nonacid reflux B. Occurs in 5%–20% o patients with gastroesophageal reflux disease (GERD) C. Approximately 0.5% of patients per year will develop cancer. • III. Diagnosis : Detected at endoscopy by its characteristic tongues of salmoncolored mucosa in the lower esophagus. When suspected, multiple biopsies are recommended to assess for dysplasia or malignancy
How is management of barett's esophagus?A. Barrett without dysplasia: surveilled with endoscopy and biopsy every 3 years B. Low-grade dysplasia - Can be surveilled annually or progression to high-grade dysplasia - Endoscopic radiofrequency ablation (RFA) or fundoplication: may cause dysplasia to regress but there has been an inconsistent response C. High-grade dysplasia - Esophagectomy: common management method due to risk of progression to cancer - Endoscopic mucosal resection and RFA: aggressive, but these therapies are in their nascent stages
How is 360-degree wrap?• Laparoscopic Nissen fundoplication • The procedure of choice for the majority of patients • This approach provides a direct and early view of the short gastric vessels and spleen • Early mobilisation of the fundus • Right crural dissection is then performed by opening the lesser omentum. • Dissection of the right crus reveals the dissected left crus • Care must be taken to preserve the vagi which will be contained by the wrap • A Penrose drain is placed around the esophagus to facilitate more proximal dissection and to assist in creating a wrap • The crura are approximated posteriorly using interrupted nonabsorbable stitches to allow the passage of a 52-Fr. bougie
What is partial fundoplication? When esophageal motility is poor, partial fundoplication may be considered to prevent obstruction to bolus propagation in the esophagus  Recent studies have shown that a total fundoplication can be performed in most patients with impaired esophageal motility  These partial wraps may be performed either anterior or posterior to the esophagus
What is anterior partial fondoplication?• No need to dissect the posterior attachments of the esophagus • The gastric fundus is folded over the anterior aspect of the distal esophagus • Usually performed in patients with achalasia after an anterior myotomy is performed
What is partial posterior fondoplication?• Posterior esophageal attachments are dissected as with the 360-degree wrap • The crura are approximated • The fundus is sutured along the anterolateral aspects creating a 220 to 250-degree wrap
What are outcomes of GERD operations?• Symptom response to the operative treatment of GERD is excellent (90-94%) • The laparoscopic technique was introduced in 1990’s, so no long-term follow-up results are available, yet early reports are comparable to the open approach • Treatment failures associated with surgical therapy are far less common than with medical therapy
What are GERD operation complications?• Reported in up to 3-10% of patients • General vs. specific to operation • Identified at the time of operation vs. post-operative Operative: • Pneumothorax is one of the most common intraoperative complications (5-8%), This CO2 pneumothorax does not need to be evacuated because it is rapidly absorbed, Approach: O2 therapy and CXR within 2 hour • Gastric and esophageal injuries in1% of cases • Result from overaggressive tissue manipulation or passage of the bougie • If unidentified during the procedure, a second operation may be needed to repair the visceral injury • Splenic injury (2.3%) yet is < 0.1% in high-volume centers • Liver injury decreased with the use of a fixed retractor
How is GERD operation failure?• Persistence of symptoms and physiologic evidence of continued acid exposure • Incidence 5% • An esophagogram should be performed: 1. No anatomic abnormality: acid suppression 2. Anatomic abnormality (herniation, failing wrap..): reoperation is indicated