The document provides an overview of the anatomy, embryology, imaging, and physiology of the esophagus. It discusses the esophagus' layers, blood supply, lymphatic drainage and innervation. Imaging modalities like barium swallow, endoscopic ultrasound, CT and MRI are described. Barium swallow is useful for evaluating disorders while endoscopic ultrasound is best for T-staging cancer. CT is optimal for assessing extraesophageal disease and lymph nodes. The esophagus acts as a conduit between the pharynx and stomach during swallowing.

1. EVERYONE

2. IMAGING ANATOMY OF
OESOPHAGUS
DR.Sateesh kumar
Primary D.N.B
KMIO

3. Introduction
Embryology
Gross Anatomy
Blood, Nervous supply
 lymphatic drainage
Physiology of
swallowing(oesophageal
phase)
Imaging Modalities
Conclusion

4. Introduction:
The esophagus serves as a
conduit between the
pharynx and the stomach .
 It begins at the
cricopharyngeus (c5-C6)
 passes through the
diaphragm to join the
cardia of stomach (D10)
 Length 23-37 cms
correlates with
individual's height and it is
usually longer in men than
in women.

5. Normal wall Thickness:
adequately distended: 3mm
incompletely distended:5mm
A-P diameter <16mm
Lateral diameter <24mm
New born :
length: 8-10cms
starts at c4-c5 up to T9

6. Anatomically divided
into three parts
Cervical(jn to notch)
4-5cms
Thoracic(notch to
hiatus)
abdominal
Functionally divided
into
upper esophageal
sphincter
esophageal body
lower esophageal
sphincter

7. UES
3 cm long zone of increased pressure at upper end
of esophagus
Relaxes with swallowing – normally remains
closed (prevents swallowing of air with
inspiration)
Located at the C5-C6 level
same as criopharyngeus muscle

8. LES (functional sphincter)
3-5 cm zone of increased pressure at lower end of
esophagus
Relaxes with swallowing
Contracts thereafter in sequence with transmitted
pressure increases – prevents reflux
Sphincter tone provided by intrinsic myogenic
activity
Sphincter relaxation due to neural activity

9. Esophagogastric Junction Definitions
The mucosal junction is marked by irregular
interdigitations, hence the term ‘Z line’. (ora serrata
or Z line) – most clinically practical
Point at which tubular esophagus joins gastric pouch
Junction of esophageal circular muscle layer with
oblique sling fibers of stomach (loop of Willis or
collar of Helvetius)
The gastro-oesophageal junction is found
constantly 40 cm distance from the incisor teeth.

10. Embryology:
Foregut
Intraembryonic part of
yolksac
10th
week single
esophageal lumen with
a superficial layer of
ciliated epithelial cells
4th month - stratified
squamous
epithelium except
upper n lower ends

11.  primitive foregut endoderm is the origin for both the
future esophageal epithelium and submucosal glands.
smooth muscle ,- mesenchyme of the somites
surrounding the foregut.
 striated muscle-mesenchyme of the branchial arches
4, 5, and 6. vagus 5th
RLN 6th
.

12. Histology:
The wall of the oesophagus comprises four layers
1. The outer fibrous coat(Adventitia)
2. Muscle layer with outer longitudinal and inner circular
fibers
3. Sub mucosa
4. Mucosa.
The mucosal lining of the oesophagus is stratified
squamous epithelium throughout its length, changing to
columnar epithelium only at the gastro-oesophageal
junction
Unlike the remainder of the GI tract, the esophagus does
not have a serosal layer, thus permitting rapid
dissemination of infection and tumor

13. Striated muscle predominates in the upper
esophagus, with smooth muscle in the lower two
thirds of the esophagus.
 The transition from striated to smooth muscle varies
but usually occurs at the level of the aortic arch.

16. Course & Relations:
Cervical oesophagus:
Anteriorly: trachea
Posteriorly: vertebral
column
Laterally: carotid sheath
Thyroid

17. Course & Relations
At the thoracic inlet,- it
lies slightly to the left of
midline
At the mid chest -
closely apposes the left
mainstem bronchus and
the pericardium of the
left atrium
Distally lies anterior to
the descending aorta to
the left of midline as it
enters its diaphragmatic
hiatus.

18. Course & Relations
 The esophagus abuts the pleura on the right but is
relatively protected from the left pleural space by the
intervening aorta.
As a result, processes involving the mid-thoracic
esophagus tend to spread into the right pleural space.
On CT, there may be small collections of air in the
esophageal lumen, but the presence of fluid or a
luminal caliber greater than 10 mm is abnormal and
suggests obstruction or a motility disorder

19. Oesophageal impressions: (constrictions)
Cervical : cricoid
Thoracic : Arch of aorta, left main bronchus,left
atrium.
Abdominal: oesophageal hiatus

20. Anatomy – Blood Supply
Cervical – inferior thyroid
arteries
Thoracic – 4-6 aortic
esophageal arteries and
branches of left bronchial
arteries
Abdominal – left gastric
artery and inferior phrenic
artery
Rich interconnecting
submucosal arterial plexus
– runs longitudinally

21. Venous Drainage
Subepithelial channels
Periesophageal plexus
Cervical drainage –
inferior thyroid veins
Thoracic drainage –
azygos/hemiazygos
veins
Abdominal drainage –
left gastric vein

22. Anatomy – Lymphatic Drainage
Vessels run
longitudinally, then
penetrate wall to enter
regional nodes
Cervical – lt
supraclavicular
Thoracic – tracheal,
tracheobronchial,
posterior mediastinal,
diaphragmatic
Abdominal – celiac axis

23. Esophagus Innervation
. A rich network of intrinsic neurons capable of
producing secondary peristalsis is found in the
submucosa and between the circular and
longitudinal muscle layers.
 This network communicates to the central
nervous system via the vagi(parasympathetic) and
sympathetic
 Cervical: from superior and inferior cervical
sympathetic ganglia
Thorax: from upper thoracic and splanchnic
nerves
Abdominal: from celiac ganglion

24. Physiology of Swallowing
Primary peristalsis – progressive, triggered by
voluntary swallowing
Secondary peristalsis – progressive, generated by
distention or irritation usually from bolus not
traversing through the esophagus.propels
remaining bolus distally.
Tertiary peristalsis – nonprogressive
(simultaneous) and uncoordinated, after
voluntary or spontaneously between swallows –
responsible for “corkscrew” appearance of spasm
of Barium Swallow

25. Imaging modalities
Plain radiography
Contrast Swallow
USG
CT
MRI
PET CT
Radionuclide scan

26. Plain Radiography:
 Per se plain chest xray
is not modality for
imaging Normal
oesophagus
 A chest radiograph
may give clue regarding
perforation ,foreign
bodies, achalasia etc.

27. Contrast swallow
Contrast medium::
Single contrast
1. Barium sulphate 80% suspension
2. Gastrografin
3. Gastromiro (Iopamidol) non ionic water
soluble
Gastrografin should NOT be used for the investigation of a tracheo-
oesophageal fistula or when aspiration is a possibility.
Barium should NOT be used if perforation is suspected.

28. Double contrast study: 200-250% high density , low
viscocity 15-20ml . Effervescent powder(or NG Tube)
is given with another mouth full of barium.
Erect>prone>supine
Medications: Buscopan or glucagon for hypotonia for
longer retention (not for assessment of motility
disorders)
Positions: RAO ,LAO, Frontal,Lateral in erect
Motility disorders(prone swallow)
Severe dysphagia?? 5ml diluted barium initially further filming n
contrast based on abnormality observed

29. Barium has superior contrast qualities and unless
there are specific contraindications, its use (rather
than water-soluble agents) is preferred.
Rapid serial radiography (2 frames per s) or video
recording may be required for assessment of the
laryngopharynx and upper oesophagus during
deglutition

30. The patient is in the erect RAO position to throw the
oesophagus clear of the spine.
 An ample mouthful of barium is swallowed, and spot
films of the upper and lower oesophagus are taken.
.
If rapid serial radiography is required, it may be
performed in the right lateral, RAO and PA positions

31. AP or PA Projection
Pt. supine or prone
Center midsagittal
plane to cassette
Bottom of cassette
should be placed just
below tip of xyphoid
Pt. drinks contrast
before exposure and
continues drinking
during exposure

32. Structures Shown/Film Evaluation
Entire barium filled
esophagus from lower
neck to stomach
Barium should be
sufficiently penetrated
Surrounding structures
should be visible, not
overpenetrated
No rotation on AP, PA, or
lateral projections
Esophagus should be
displayed between heart
and spine on oblique
projections

33. Lateral Projection
Place pt in lateral
position
Center midcoronal
plane to cassette
Bottom of cassette
below xyphoid process
Pt must drink
continuously before
and during exposure

34. RPO VIEW
LATERAL VIEW

35. Tertiary peristalisis
Primary follows

37. Bulbous distention of
the distal esophagus is
called the vestibule and
corresponds to the
manometrically-defined
lower esophageal
sphincter.

This distention is best
demonstrated by breath
holding in inspiration or
a Valsalva maneuver.
Do not mistake this for a
hiatal hernia.

38. USG:
Cervical esophagus –
can be seen posterior to
Left lobe of thyroid in
routine usg neck
Linear probe : 7.5-
10MHz

39. USG:
GE-JUNCTION can be
visualised in trans-
abdominal sonography
Curvilinear probe:
3-5Mhz

40. Endoscopic USG:
Evolved as the imaging
modality of choice for
entire oesophagus.
Helps in visualising wall
layers of oesophagus
thus in perfect T-
staging( superior to CT)
Helps in taking needle
biopsy of suspected
growth and suspicious
surrounding
lymphnodes.

41. EUSG PROBES:
Standard EUS(S-EUS)
Probes combine
endoscopy with usg
7.5-12 MHz
Radial , linear based on
plane of scanning

43. E-Usg probes
Catheter USG (C-Usg
probes)
High resolution
15-30MHz
Advantages:
Technically ease
Short imaging time
Lack of compression
effect on small tumors A-MINI-PROBE
B.MINIPROBE WITH BALLOON SHEATH
C.BLIND ESOPHAGOPROBE

44. Using conventional
imaging frequencies,
the gastrointestinal
wall is displayed as 5
layers of alternating
black and white echo-
layers by endoscopic
ultrasound

45. S-EUS- 5layered wall
Inner(1)-outer(5)
 1st layer -bright (hyper-echoic)
- superficial mucosa.
 2nd (dark, hypoechoic)- deep
mucosa.
 3r d (hyperechoic)-
submucosa and the acoustic
interface between the
submucosa and the muscularis
propria.
 4th (hypoechoic) – muscularis
propria
 5th layer corresponds to the
adventitia

46. C-EUSG-9 Layered wall
 Layers 1-4 represent the
mucosa.
1,2 – epithelium
3- lamina propria,
4- muscularis mucosa.
5-submucosa.
6-8proper muscle layers
6- circular muscle
 7- connective tissue and
interface,
8-longitudinal muscle.
9- adventitia

48. CT-Protocol
Patient position: supine with arms elevated above
level of head
Topogram position: AP 1 inch below chin to
umbilicus
Mode : Helical CT with single breath hold, thus
reducing breathing and cardiac artifact
Scan orientation: caudocranial.
starting point: Imaginary line joining both cp angles
end point: 1cm above apex of lung
 High-density or positive oral contrast material
swallowed directly before CT is helpful in delineating
the esophageal lumen.

49. Scanning is performed during the portal venous
phase and intravenous contrast administered at a rate
of 2 to 4 mL/sec.
 Slice thickness should be no more than 5 mm
throughout the chest.
In patients with suspected esophageal varices, water
is used as a negative contrast agent combined with
intravenous contrast.

50. A positive oral contrast agent combined with
intravenous contrast can obscure submucosal
vascular structures.
Multiplanar reformatted images may also be helpful,
particularly in the staging of esophageal cancer.
CT has advantage over mri in detecting lymohnodes
with more accuracy

57. MRI
The advent of fast, breath-hold MR sequences has
increased the utility of MR in evaluation of the GI
tract.
 But there is still role for MR imaging in evaluation of
the esophagus is limited.
 Cardiac gating must be incorporated, and coverage of
the entire esophagus in a single breath-hold sequence
remains problematic .

59. T1 post GAD

62. PET-CT: For picking metastasis and extent of spread
of malignancy with in the esophagus
Nuclear medicine: Prime role for assessing
oesophageal motility disorders and reflux disease
especially in young children.
Endoscopy : Is now the investigation of choice for
evaluating as well as obtaining biopsy at the same
setting. However lack of spatial resolution and in
ability to look out side the lumen are the limitations.

64. conclusion
Chest xray - no/limited role in evaluating oesophagus.
Ba. Swallow is most useful modality in evaluating
oesophageal disorders
 Normal variants in barium swallow should not
be misinterpreted
Endoscopic Usg is imaging modality of choice for T-
staging of oesophageal cancer and to check
extraluminal contiguous extension
CT scan is THE imaging modality for evaluating
extraluminal disease and nodal disease in carcinoma.
MRI has limited role in evaluating oesophageal
disease
Radionucleotide scans are useful in motility disorders

65. Thank You