Sabiston Esophagus Flashcards
Esophagus Coarse
-The cervical esophagus begins as a midline deviates slightly to the left of the trachea as it passes through the neck into the thoracic inlet
-At the level of the carina, it deviates to the right to accommodate the arch of the aorta.
-It then winds its way back under the left mainstem bronchus and remains slightly deviated to the left
Killian triangle
-The inferior pharyngeal constrictor muscle is composed of two consecutive muscle beds—the thyropharyngeus and cricopharyngeus muscles—
-The transition between the oblique fibers of the thyropharyngeus muscle and the horizontal fibers of the cricopharyngeus muscle creates a point of potential weakness
The circular muscles are an extension of the
cricopharyngeus muscle
Then they become the middle circular muscles of the lesser curvature of the stomach
The collar of Helvetius
the transition of the circular muscles of the esophagus to oblique muscles of the stomach at the incisura (cardiac notch)
Three distinct areas of narrowing that contribute to its shape.
1-cricopharyngeus muscle is the narrowest point of the gastrointestinal tract
2-bronchoaortic constriction at the level of the fourth thoracic vertebra
3-the diaphragmatic constriction
The UES corresponds reliably to the
to the cricopharyngeus muscle
There are two anatomic considerations that may be used to identify the GEJ
1-The squamocolumnar epithelial junction (Z-line)
2-The transition from the smooth esophageal lining to the rugal folds of the stomach may also identify the GEJ
Externally
1-the collar of Helvetius (or loop of Willis), where the circular muscular fibers of the esophagus join the oblique fibers of the stomach
2-the gastroesophageal fat pad
Blood Supply to Esophagus
-The cervical esophagus > inferior thyroid arteries > branch off of the thyrocervical trunk on the left and the subclavian artery on the right
-The cricopharyngeus muscle, marks the inlet of the esophagus > superior thyroid artery.
-The thoracic esophagus four to six esophageal arteries coming off the aorta + branches off the right and left bronchial arteries + descending branches off the inferior thyroid arteries, intercostal arteries, and ascending branches of the paired inferior phrenic arteries.
-The abdominal esophagus > the left gastric artery and paired inferior phrenic arteries.
Venous Drainage of Esophagus
-submucosal venous plexus is the first basin for venous drainage
-cervical esophagus > the submucosal venous plexus drains into the inferior thyroid veins
-The thoracic esophagus > submucosal venous plexus joins with the more superficial esophageal venous plexus and the venae comitantes > drains into the azygos(RT) and hemiazygos(LT) veins
-The intercostal veins > drain into the azygos venous system.
-The abdominal esophagus > systemic and portal venous systems through the left and right phrenic veins and left gastric (coronary) vein and short gastric veins
The superior laryngeal nerve
external : motor innervation to the inferior pharyngeal constrictor muscle and cricothyroid muscle
internal : sensory innervation to the larynx
recurrent laryngeal nerves
right : loop underneath the right subclavian
left : loop underneath the aortic arch
then travel upward in the tracheoesophageal groove to enter the larynx laterally underneath the inferior pharyngeal constrictor muscle.
innervate the cervical esophagus, including the cricopharyngeus muscle
three types of esophageal contractions
-Primary peristaltic contractions : progressive and move down the esophagus at a rate of 2 to 4 cm/sec
-Secondary : also progressive but are generated from distention or irritation of the esophagus rather than voluntary swallowing.
-Tertiary contractions : nonprogressive, nonperistaltic, monophasic or multiphasic
esophageal motility disorders have been classified into primary and secondary causes
Primary : achalasia, diffuse esophageal spasm (DES), nutcracker (jackhammer) esophagus, hypertensive LES, and ineffective esophageal motility (IEM).
Secondary : from progressive damage induced by an underlying collagen vascular or neuromuscular disorder;
scleroderma, dermatomyositis, polymyositis, lupus erythematosus, Chagas disease, and myasthenia gravis
Diffuse(Distal) Esophageal Spasm
-Manifested in a similar fashion to achalasia
-Motor abnormality of the esophageal body
- Muscular hypertrophy and degeneration of the branches of the vagus nerve
-Contractions are repetitive, simultaneous, and of high amplitude.
- Regurgitation of esophageal contents and saliva is common
-acid reflux can aggravate the symptoms.
-gallstones, peptic ulcer disease, and pancreatitis, all trigger DES
-corkscrew esophagus or pseudodiverticulosis on an esophagram
-A distal bird beak narrowing of the esophagus
Nutcracker Esophagus
-characterized by excessive contractility
-is the most common of all esophageal hypermotility disorders
-most painful of all esophageal motility disorders.
-An esophagram may or may not reveal any abnormalities
EGJ outflow obstruction (Hypertensive Lower Esophageal Sphincter)
-evidence of effective peristalsis that is not present in achalasia
-diagnosis by manometry with a hypertensive, poorly relaxing sphincter
-esophagram may show narrowing at the GEJ with delayed emptying and abnormalities of esophageal contraction
progressive Achalasia leads to
aspiration
Pneumonia
lung abscess
bronchiectasis
Achalasia is also known to be a premalignant condition
Squamous cell carcinoma (SCC) is the most common type
Feature of Achalasia on Esophagogram or xray
-Lack of a gastric air bubble is a common finding
advanced stage of disease > massive esophageal dilatation, tortuosity, and sigmoidal esophagus (megaesophagus)
Esophagectomy is considered in Achalasia
in any symptomatic patient with a tortuous dilated esophagus (megaesophagus)
sigmoid esophagus
failure of more than one myotomy
or reflux stricture that is not amenable to dilatation
megaesophagus Sx
total esophagectomy incorporating a transthoracic dissection may be safest
Use of POEM
may obviate the need for esophagectomy in this malnourished, often high-risk, patient population.
Diverticular Disorders
The three most common sites of occurrence are
pharyngoesophageal (Zenker)
parabronchial (midesophageal)
epiphrenic (supradiaphragmatic)
false pulsion diverticula
Zenker diverticulum and an epiphrenic diverticulum
Traction, or true, diverticula
-from external inflammatory mediastinal lymph nodes pulling the esophagus
-more common in the midesophageal region around the carinal lymph nodes
The most serious complication from an untreated Zenker diverticulum
is aspiration pneumonia or lung abscess.
Dx of Zenker
Lateral views are critical because this is usually a posterior structure.
small diverticulum (<2 cm)
myotomy alone is often sufficient
patients with good tissue or a large sac (>5 cm), excision of the sac is indicated
Midesophageal Diverticula
-inflamed mediastinal lymph nodes tuberculosis accounted for most cases
-histoplasmosis and resultant fibrosing mediastinitis have now become more common
Midesophageal diverticula Approach
-barium esophagram > typically are on the right
-CT scan > identify any mediastinal lymphadenopathy
-Endoscopy > rule out mucosal abnormalities identifying a fistula.
-Manometric studies > identify a primary motor disorder.
Treatment is guided by the results of the manometric findings
midesophageal diverticula Tx
-treatment of the underlying cause is the management of choice.
-diverticulum smaller than 2 cm can be observed.
-If patients progress to become symptomatic or diverticulum 2 cm or larger, surgical intervention is indicated
Epiphrenic Diverticula
-in the distal third of the esophagus, within 10 cm of the GEJ.
-related to thickened distal esophageal musculature or increased intraluminal pressure
-associated with DES, achalasia, or hypertensive LES disorders.
-If no motility abnormality > congenital (Ehlers-Danlos syndrome) or traumatic cause is considered.
-As with midesophageal diverticula, epiphrenic diverticula are more common on the right side
epiphrenic diverticulum Tx
Small (<2 cm) diverticula can also be suspended from the vertebral fascia and need not be excised.
If a diverticulopexy is performed, a myotomy is begun at the neck of the diverticulum and extended onto the LES.
If a diverticulectomy is pursued, a vertical stapling device is placed across the neck and the diverticulum is excised
basic tenets of antireflux surgery
(1) preserve natural tissue planes and linings
(2) identify and preserve both vagus nerves
(3) identify the true EGJ for placement of the wrap
(4) have sufficient length of intraabdominal esophagus
(5) reestablish the angle of His
in Gerd Sx A consideration for patients with bile or gastric reflux, morbid obesity, diabetes, or esophageal dysmotility
is Roux-en-Y reconstruction
Caustic Ingestion
1-examination findings of upper airway
2-bronchoscopic guidance for ETT and preparation to perform cricothyroidotomy
3- CT scan of chest and abdomen with intravenous and oral administration of contrast followed by a barium swallow study
4-endoscopic evaluation > done early in the hospital course as the risk of perforation increases after 48 hours. Pediatric endoscopes are useful
should not proceed past an area of circumferential injury
endoscopic findings
see
Schatzki ring
-Nonmalignant, fibrous thickening and narrowing of the GEJ
-Concomitant finding of hiatal hernia
-Tx dilatation (bougie or balloon)
-Bx to rule out malignancy.
-Repeated dilatation often necessary
-Persistent strictures suspicion for malignant disease
Benign Tumors of the Esophagus
-Granular cell tumors :
from Schwann cells
mucosa or submucosa
distal third of the esophagus
Tunneled biopsies : eosinophilic granules
stain positive for S100,
Atypical features on EUS, large (>2 cm), symptomatic > reasonable indications for excision
Fibrovascular polyps
-cervical esophagus at or near the cricopharyngeus
-heterogeneous group of soft tissue tumors
-cylindrical or elongated, with a stalk
Squamous papillomas
-exophytic projections, wart-like
-crossing vessel on the surface
-link with (HPV)
-excision is warranted to rule out carcinoma
Benign submucosal tumors
lipomas, hemangiomas, and neural tumors.
Lipomas: homogeneous, hyperechoic, smooth appearance on EUS.
Resection is seldom warranted.
Hemangiomas :purple or reddish nodule. EUS > smooth, hypoechoic, submucosal mass
Neural tumors including neurofibromas and schwannomas are rare
Leiomyomas
-MC benign tumors of the esophagus.
-usually asymptomatic
-large tumors may cause dysphagia
-arise in the muscularis propria
-found in the mid to distal esophagus.
-EUS > hypoechoic, regular borders, arise from the fourth endosonographic layer.
-should not be biopsied > complicate subsequent attempts at enucleation.
-Small, asymptomatic > safely observed without biopsy.
-Symptomatic lesions > enucleated,
-large lesions > removed with a VATS approach/Endoscopic
Rare Malignant Tumors of the Esophagus
-Primary melanoma of the esophagus
-Sarcomas and GISTs of the esophagus
-leiomyosarcomas
leiomyosarcomas differentiation from Leiomyoma
erode through the mucosa, appearing as an ulcerated or exophytic mass on endoscopy
GIST vs leiomyomas
-distinguished histologically by CD117 (c-kit) and CD34 stain positivity
-tend to be larger, with uptake of IV contrast on CT, and significant (PET) avidity.
-enucleated If negative margins can be obtained.
-Otherwise formal esophagectomy
-Imatinib > considered for any GIST larger than 3 cm or with other high-risk features.
-Imatinib > considered in the neoadjuvant setting for locally advanced tumors.
SCC associated disorders
-Plummer-Vinson syndrome
-achalasia
-tylosis
-Fanconi anemia
Tumor location by Endoscopy
-cervical esophagus begins at the hypopharynx and extends to the thoracic inlet, which is the level of the sternal notch.
-On endoscopy > 15 to 20 cm from the incisors.
-The upper thoracic esophagus begins at the thoracic inlet and extends to the azygos vein.
20 to 25 cm from the incisors.
-Midthoracic tumors from the lower border of the azygos vein to the inferior pulmonary vein.
25 to 30 cm from the incisors.
-Lower tumors arise distal to the lower border of the inferior pulmonary vein to the GEJ.
more than 30 cm from the incisors.
When to Do Bronchoscopy for Esophageal CA
performed for proximal and middle third esophageal tumors to assess for direct tracheal invasion
When is EMR better than EUS
superficial tumors (T1a–T2)
the accuracy of EUS is significantly diminished and EMR provides the most accurate staging information
American College of Gastroenterology guidelines for low-grade dysplasia and HGD
-all patients with low-grade dysplasia undergo endoscopic eradication therapy
-yearly endoscopic surveillance being an acceptable alternative.
All patients with high-grade dysplasia should undergo endoscopic therapy if medically able to tolerate the procedure.
One advantage of cryotherapy compared with RFA
cryotherapy does not require a probe to be in contact with the tissue
Patient with failed RFA
cryotherapy has been used as salvage therapy
when to repeat endoscopy after ablative therapy
HGD > three months after ablative therapy
LGD > 6 months after their Barrett esophagus/dysplasia is completely eradicated
What is buried glands
Barrett epithelium could be hidden beneath areas of the new squamous epithelium ( after Ablative therapy )
Endoscopic Resection Vs Ablative
limitation of ablative therapies :
-limited depth of penetration
-lack of definitive pathologic analysis.
patients with nodular or raised Barrett esophagus or other abnormalities suggestive of superficial invasive cancer should undergo EMR rather than ablation
NCCN guidelines for Tis,T1a and T1b
-EMR ± ablation in patients with Tis and T1a
-Superficial T1b (SM1) patients with adenocarcinomas and low-risk features, endoscopic eradication is a reasonable alternative to surgery.
Candidates for Esophagectomy
-High-risk T1a lesions
(larger tumors or lesions with lymphovascular invasion)
-Extensive, multifocal lesions and ulcerated tumors may also be difficult to eradicate endoscopically
Who might benefit from induction therapy for T2N0
long tumors (>3 cm)
presence of lymphovascular invasion
and high-grade as clinical factors
What can affect patient survival
nodal location, such as celiac axis or upper mediastinum, may significantly affect survival
Regional LN for SCC and Adenocarcinoma
-adenocarcinoma located in the distal esophagus or GEJ
LN > celiac axis up to the paratracheal region
-SCC, in mid or proximal esophagus
LN > periesophageal cervical lymphadenopathy is still considered a regional disease
Main cause of Death
Distant recurrence or metastatic disease
The synergistic effect of chemoradiation combined with surgical resection
maximizes the chances of effectively treating both locoregional disease and potential undetectable metastases
