Motility Disorders and Achalasia - الأهلية

• Lecture focuses on motility disorders and achalasia related to surgery

Introduction

• Patients with motility disorders may present with dysphagia
• Barium swallow may not show a stricture but demonstrate poor emptying
• Motility testing is positive
• Motility testing is not always positive
• Pain with or without difficulty swallowing is a common symptom
• Extensive hospital investigations often precedes diagnosis of esophagus issues
• Symptoms include chest pain, dysphagia and regurgitation and are intermittent
• Correlation between symptoms and test abnormalities can be poor
• Esophageal dysmotility is a feature of a general disturbance in GI function

Classification of Motility Disorders

• UES disorders include Cricopharyngeal spasm, Zenker's diverticulum, and Plummer Vinson syndrome
• Body disorders are Diffuse esophageal spasm, Nutcraker esophagus, Non-specific motility disorders
• LES primary disorder is Achalasia
• LES secondary disorders are Hypertensive LES, Hypotensive LES, Cerebrovascular disorders, DM, Scleroderma, Collagen disease, Chagas' disease, Myasthenia gravis, and Presbyesophagus

Incidence

• Motility disorders are uncommon
• Diagnosis is not straightforward
• Symptoms may be attributed to other organs like the heart
• Cardiac workups are common because of chest pain

Achalasia

• It is a primary esophageal motility disorder
• Characterized by the absence of esophageal peristalsis and failure of the lower esophageal sphincter to relax
• Achalasia is a Greek term means failure or lack of relaxation
• Achalasia is rare
• Incidence is 1 per 100,000
• Onset is usually in middle to late adulthood between ages 30 to 70
• Cause is unknown, but may be from degenerative disease of neurons or infection of neurons by herpes zoster virus or Treponozomi cruzi

Pathogenesis

• Degeneration of the ganglion cells of myenteric plexus of Auerbach are the main cause
• There is selective degeneration of postganglionic inhibitory neurons (mediate LES relaxation)
• In the smooth muscle layers of the esophagus, propagation of peristaltic waves in response to swallowing is absent; instead, there are simultaneous contractions
• No peristalsis occurs
• Postganglionic cholinergic neurons are spared leads to unopposed cholinergic stimulation cause increased LES resting pressure and failure of LES relaxation

Pathophysiological Changes

• Esophagus remains normal caliber with contractile activity early
• Esophagus dilates, contractions disappear over time
• Esophagus empties primarily by hydrostatic pressure and is often incomplete
• Megaesophagus is a markedly dilated tortuous esophagus with persistent esophagitis.

Complications

• Esophagitis
• Aspiration of retained undigested food leads to pneumonia
• Epiphrenic diverticulum
• Esophageal cancer, specifically squamous cell carcinoma
• Adenocarcinoma in patients who develop gastroesophageal reflux, after pneumatic dilatation or myotomy

Clinical Presentation

• Usually presents in middle age, with equal incidence in men and women
• Dysphagia is the most common symptom
• Dysphagia is often with both solids and liquids
• Regurgitation of undigested food at 60%
• Heartburn 40% from of stasis and fermentation of undigested food in the distal esophagus
• Chest pain 40% with meals
• Aspiration pneumonia and malignant dysphagia can occur

Vomiting, Regurgitation, and Reflux

• Vomiting requires effort
• Regurgitation and reflux are often used synonymously
• It is helpful to differentiate between them
• Regurgitation refers to esophageal contents returning from above a functional or mechanical obstruction from above
• Reflux is the passive return of of gastroduodenal contents to the mouth and a symptom of GERD

Investigations

• Barium swallow is the first test performed when evaluating dysphagia
• Upon barium swallow, barium will will hold up in the distal esophagus with smooth narrowing at the level of the GEJ creating a bird beak appearance
• Dilated or sigmoid esophagus can appear in long-standing achalasia
• Absent air bubble in the stomach
• Simultaneous contractions may be noticed
• The classic manometric findings are absence of esophageal peristalsis and the LES that relaxes only partially upon swallowing; can be hypertensive in 50% of cases
• HRM (High Resolution Manometry)
• Endoscopy is performed to rule out a tumor of the gastroesophageal junction
• Endoscopy may show a dilated esophagus with food residue and a spastic cardia that shows resistance to the endoscope, complications

Manometry Diagnosis

• The diagnosis is based on the manometry criteria
• Complete absence of progressive primary peristaltic contractions
• Incompletely relaxing LES which will not be hypertensive, normotensive or hypotensive.

Classification

• The Chicago classification scheme separates achalasia into types I, II, III:
  • Type I is with complete absence of esophageal contractions and no pressurization
  • Type II is with simultaneous pressurization
  • Type III is with high-pressure non-peristaltic body contractions
• Chicago classification correlates with treatment outcome
• Different success rates can be expected in the treatment of disease

Differential Diagnosis

• Benign strictures due to gastroesophageal reflux
• Esophageal carcinoma

Establish the Diagnosis

• Endoscopy
• Endoscopic ultrasound
• CT scan
• Infiltrating tumor of the gastroesophageal junction can mimic achalasia
• The clinical presentation and manometric profile can be secondary

Treatment

• Suspect if patient is older than 60 with recent dysphagia symptoms less than 6 months and weight loss
• Therapy is palliative
• Treat by decreasing the lower esophageal sphincter resistance
• Peristalsis is absent, so emptying uses gravity
• Surgical treatment is by Laparoscopic Heller myotomy with partial fundoplication or procedure of choice

Surgical technique

• Myotomy is of the lower esophagus, 6 cm and proximal stomach, 2 cm
• Procedure is Followed by an anterior or posterior partial fundoplication to prevent reflux
• Success Rate is 90% with Postoperative reflux at 15%
• Esophagectomy can be reserved if patients have severe dysphagia who have failed both dilatation and myotomy

Endoscopic Procedures

• Intrasphincteric injection of botulinum toxin blocks the release of acetylcholine at the LES
• It is temporary and has to be repeated after a few months with restricted use in elderly patients with other comorbidities
• Pneumatic dilatation can be the main modality of treatment
• Postdilatation reflux is about 25-35%
• These patients who fail pneumatic dilatation get Heller myotomy
• POEM, per oral endoscopic myotomy is an advanced endoscopic technique, gaining acceptance as a new main modality of treatment
• Greater than 90% relief after short-term with greater than 80% relief after long-term follow-up

POEM Complications

• The incidence of iatrogenic GERD ranges from no reflux to an incidence of almost 50%

Medical treatment

• Calcium-channel blockers decrease LES pressure
• Benefits only 10%
• Used only if patients have contraindications to pneumatic dilatation or surgery

Other Motility Disorders

• Diffuse Esophageal Spasm happens in the body of the esophagus
• Patients complain of dysphagia with chest pain due to incoordinate contractions
• Spastic pressures may reach 400-500 mmHg
• Barium swallow will show a "corkscrew esophagus”
• There is no proven pharmacological or endoscopic treatment

Zenker's Diverticulum

• Zenker's diverticulum is in the upper esophageal sphincter and is a pharyngeal pouch
• It protrudes posteriorly above the cricopharyngeal sphincter through a weak point which is the dehiscence of Killian
• It involves loss of the coordination between pharyngeal contraction and opening of the upper sphincter
• It is small with pharyngeal dysphagia
• It tends to fill with food on eating and enlarges
• Halitosis and esophageal dysphagia occurs as the pouch enlarges and descends into the mediastinum
• Pt will present with a lateral neck swelling, which causes regurgitation caused by compression
• Treatment by division of the septum of the diverticulum and esophagus endoscopically creating a diverticulo-esophagostomy and open surgery

Plummer-Vinson Syndrome

• Plummer-Vinson syndrome is a kind of Paterson-Kelly syndrome or sideropenic syndrome
• Presents with dysphagia and iron deficiency anemia leading to glossitis and koilonychia
• Dysphagia occurs from a post-cricoid web in the upper and middle esophagus
• Diagnosed coincidentally by contrast radiology
• Symptomatic webs may rupture during endoscopy
• The patient requires formal endoscopic dilatation