The document summarizes the anatomy and physiology of the pharynx and esophagus. It describes the pharynx as a funnel-shaped passageway divided into three regions (nasopharynx, oropharynx, laryngopharynx) with two layers of skeletal muscle. It then discusses the esophagus, describing it as a muscular tube that connects the pharynx to the stomach and passes through the diaphragm. Key details about the parts, constrictions, histology, blood supply, innervation and physiology of swallowing for both the pharynx and esophagus are provided.

1. Esophagus
QAP20704
Dr. Mohanad

2.  Pharynx is an incomplete
striated muscular tube.
 It is a funnel-shaped
passageway leading from
the oral and nasal cavities in
the head to the esophagus
and larynx.
 The pharynx chamber serves
both respiratory and
digestive functions.
Pharynx

3.  The pharynx is divided into
three regions.The
nasopharynx, oropharynx,
and the laryngopharynx.
 The mucosa is composed of
stratified squamous
epithelium which is supplied
with mucus producing
glands.
Pharynx

4. Pharynx

5.  The muscles of the
pharynx consist of 2
skeletal muscle layers.
 The inner longitudinal
layer.
 The outer circular layer.
Muscle of Pharynx

6. Circular layer
1. Superiorpharyngeal
Constrictors Muscle
2. Middlepharyngeal
Constrictors Muscle
3. Inferior Pharyngeal
Constrictors Muscle
Innervation =Vagus
nerve [X]
Muscle of Pharynx

7. 3 longitudinal muscles :
 Stylopharyngeus
Muscle
 Salpingopharyngeus
Muscle
 Palatopharyngeus
Muscle
Muscle of Pharynx

8. Blood is supplied to
pharynx by:
1. Ascending pharyngeal,
2. Tonsillar branches of
3. Facial arteries
4. Branches of maxillary
and lingual arteries .
Blood supply of Pharynx

9.  Motor: Pharyngeal
branch of the Vagus
nerve
 Sensory:
 Nasal pharynx:The
maxillary nerve (V2)
 Oral pharynx:The
glossopharyngeal nerve
 Laryngeal pharynx:The
internal laryngeal branch
of the Vagus nerve
Nerve supply of Pharynx

10.  The esophagus is a muscular
tube that connects the
pharynx to the stomach.
 Its about ten inches (25 cm).
 It passes into the abdomen
through an opening in the
diaphragm called the
oesophageal hiatus and
joins the stomach.
Esophagus

11. o The esophagus lies posterior to the
larynx, trachea and the heart In
front of the vertebral column.
o It begins in the neck at the lower
border of the cricoid cartilage,
opposite the sixth cervical vertebra
(C6)
o Descends along the front of the
vertebral column, through the
superior then posterior mediastina,
passes through the diaphragm, and,
entering the abdomen, ends at the
cardiac orifice of the stomach,
opposite the eleventh thoracic
vertebra (T11).
Esophagus

12. 1) Cervical part
2) Thoracic part
3) Abdominal part
Esophagus Parts

13.  The esophagus has
three distinct areas of
naturally occurring
anatomic narrowing
 Cervical constriction
 Bronchoaortic
constriction
 Diaphragmatic
constriction
Esophagus constrictions

14. LES (functional sphincter)
 3-5 cm zone of increased pressure at lower
end ofesophagus
 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

15. Diaphragm muscles relax,
opening the passageway.
Longitudinal muscle
Esophagus muscles relax,
opening the passageway.
Esophagus
Esophagus muscles contract,
squeezing on the inside.
Diaphragm muscles contract,
squeezing on the outside.
When the circular muscles of a sphincter contract, the
passage closes; when they relax, the passage opens.
Circular muscle
Stomach

16. Esophagus Histology
Secretes mucous, transports food – no enzymes produced, no
absorption
Mucosa: Stratified squamous epithelium; protection against wear
and tear
lamina propria:
Submucosa: moderately dense CT with blood, nerve, lymph
vessels & lymphoid follicles; rich in elastic fibers
Muscularis divided in thirds
 Superior 1/3 skeletal muscle
 Middle 1/3 skeletal and smooth muscle
 Inferior 1/3 smooth muscle
 2 Sphincters – upper esophageal sphincter (UES) regulates
movement into esophagus, lower esophageal sphincter (LES)
regulates movement into stomach
Adventitia: Consist of loose C.T no serosa – attaches to
surroundings

17. copyright (your organization) 2003 17

18.  Cervical part
:Bronchial artery.
 Thoracic part
:Thoracic aorta.
 Abdominal part
:Left gastric artery
and Left inferior
phrenic artery.
Blood Supply

19.  Cervical part: into the
inferior thyroid vein.
 Thorax part : into the
azygous system of
vein and hemiazygos
vein.
 Abdominal part :into
the left gastric vein
which empties into the
portal vein.
Venous Drainage

20.  Cervical part: drains into
paratracheal and
internal jugular nodes.
 The thorax part : drains
to mediastinal nodes.
 Abdominal part: drains
to nodes around aorta
and celiac axis
Lymphatic Drainage

21.  Upper third:
Innervated by
Recurrent Laryngeal
Nerve from the vagus
nerves.
 Lower two-thirds:
Innervated by Vagus
and Sympathetic
Chain.
Innervation

22. Physiology of
Swallowing
 Primary peristalsis –
progressive, triggeredby
voluntary swallowing.
 Secondary
peristalsis: progressive,
generatedby distention
or irritation usually from
bolus not traversing
through the esophagus.
 Tertiary peristalsis –
Tertiary waves are
defined as contractions
which occur
simultaneously at
different levels of the
oesophagus

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