Oesophageal Motility Disorders Flashcards
What are OMDs?
A group of conditions characterised by abnormalities in oesophageal peristalsis.
Epidemiology
Less common than mechanical and inflammatory diseases of oesophagus
Typically manifest with dysphagia of solids and liquids together.
What are the two major causes of oesophageal dysmotility?
Achalasia
Diffuse oesophageal spasm
Explain the oesophageal anatomy
25cm divided into thirds:
Upper third = skeletal muscle
Middle third = transition zone of both skeletal and smooth muscle
Lower third = composed of just smooth muscle
What is the upper oesophageal sphincter comprised of?
Skeletal msucle to prevent air from entering the GI tract
What is the LOS comprised of?
Smooth muscle to prevent reflux from the stomach
Explain the peristaltic waves
Controlled by oesophageal myenteric neurones.
They propel ingested food downwards.
Primary wave = is under control of the swallowing centre
Secondary wave = activated in response to distention
Dx of OMD
GORD
Oesophageal malignancy
Angina pectories
What is achalasia?
A primary motility disorder of the oesophagus.
Failure of relaxation of the LOS and progressive failure of contraction of the oesophageal smooth muscle
Epidemiology of achalasia
Quite rare
1 per 100000
Mean age of diagnosis at 50 yo
Histological feature of achalasia
Progressive destruction of ganglion cells in the myenteric plexus
Explain pathophysiology
High resting tone and failure of relaxation of LOS -> food gets stuck and can’t reach the stomach.
It also causes further dysfunction of the more proximal oesophagus.
Clinical features of achalasia
Progressive dysphagia when ingesting both solids and liquids
Vomiting and chest discomfort
Regurgitation of food
Coughing (especially at night)
Chest pain
Weight loss
Examination findings
Usually null
Might see visible weight loss in longstanding or severe cases
Ix
Oesophageal cancer always need to be excluded -> Urgent endoscopy
Gold standard for diagnosis = Oesophageal manometry
Endoscopy findings of achalasia
Should be normal but a tight LOS might be seen.
Explain oesophageal manometry.
A pressure sensitive probe is inserted into the oesophagus
It measures the pressure of the sphincter and the surrounding muscle
Three key features of achalasia on manometry.
Absence of oesophageal peristalsis
Failure of relaxation of the LOS
High resting LOS tone
When is barium swallows done in achalasia?
Rarely performed anymore.
They may show proximal dilation of the oesophagus with a characteristic bird’s beak appearance distally.
Conservative management of achalasia
Sleeping with many pillows to minimise regurgitation
Eating slowly and chew thoroughly
Plenty of fluids with meals
CCBs or nitrates can give temporary relief but action is typically short-lived.
Botox injections into LOS by endoscopy can help for a few months.
Types of surgical management of achalasia
Endoscopic balloon dilatation
Laparoscopic Heller myotomy
Explain endoscopic balloon dilatation
Insertion of a balloon in the LOS which is then dilated to stretch the muscle fibres.
Complications of endoscopic balloon dilatation
Good response in 75% of patients
Carriers the risk of perforation
Explain laparoscopic heller myotomy
Division of the specific fibres of the LOS which fail to relax.
A long-term improvement in swallowing is seen in 85% of patients
Less side-effects than endoscopic treatment.
Prognosis of achalasia
Long standing have an 8-16x increased risk of oesophageal cancer
What is diffuse oesophageal spasm DOS?
Characterised by multi-focal high amplitude contractions of the oesophagus (spasms)
Cause of DOS
Dysfunction of oesophageal inhibitory nerves
DOS can progress to achalasia
Clinical features of DOS
Severe dysphagia to both solids and liquids
Central chest pain (exacerbated by foods)
Pain from DOS can respond to nitrates (making it hard to distinguish from stable angina)
Examination is normal
Ix of DOS
Needs urgent endoscopy to rule out malignancy
Definitive diagnosis is the same as achalasia by manometry.
Barium swallow is rarely performed but cahn show a corkscrew appearance
Endoscopy findings in DOS
Usually normal
Manometry in DOS
Repetitive, simultaneous and ineffective contractions of oesophagus.
May also be dysfunction of LOS
Management of DOS
Nitrates or CCBs are first line to relax oesophageal smooth muscle.
DOS + hypertension may benefit from pneumatic dilatation.
Myotomy can be done in the most severe cases.
Myotomy in DOS
Incision involving the entire spasmodic segment and the LOS
Other causes of oesophageal dysmotility.
Autoimmune and connective tissue disorders like systemic sclerosis, polymyositis and dermatomyositis.
