The document describes the anatomy of the neck spaces. It is divided into three sections: spaces involving the entire length of the neck, spaces limited to above the hyoid bone, and spaces limited to below the hyoid bone. The key spaces described include the retropharyngeal space, danger space, parapharyngeal space, submandibular space, and anterior visceral space. Various structures form the boundaries of each space and contents are noted.

2. The anterior triangle of the neck
• It lies in front of the sternomastoid muscle .
• It is bounded by :
• 1- anterior border of sternomastoid muscle
.(behind)
• 2- anterior midline of the neck ( in front )
• 3- lower border of the mandible (base )
• It is subdivided into 4 triangles by means of the
superior belly of omohyoid muscle , the anterior
and posterior bellies of digastric muscle as
follows :

3. • 1- Digastric triangle
• 2- carotid triangle
• 3- Muscular triangle
• 4- Submental triangle

4. Anterior belly of
digastric muscle
Posterior
belly of
digastric
Stylohyoid
Sternohyoid
muscle

5. Digastric triangle Or submandibular
triangle
• Outlines :
• Above : the lower border of the mandible
• Below & infront : the anterior belly of Digastric
muscle
• Below & behind : the posterior belly of Digastric
and stylohyoid muscles .
• Floor :
• Anteriorly : the mylohyoid muscle
• Posteriorly : part of hyoglossus muscle

6. Contents of the Digastric triangle
• 1- submandibular salivary gland
• 2- the submandibular lymph nodes lie on the
surface of the gland
• 3- facial artery deep to posterior end of
submandibular salivary gland
• 4- facial vein lies superficial to submandibular
salivary gland
• 5- hypoglossal nerve
• 6- nerve to mylohyoid muscle

7. • d
Digastric triangle
Carotid triangle
Muscular triangle
Anterior belly
of digastric
Posterior belly
of digastric
Mylohyoid
muscle
forms the
floor of
the mouth

8. Carotid triangle
• Outlines :
• Behind : the sternomastoid muscle
• Infront and above : the posterior belly of digastric
muscle
• Infront and below : the superior belly of omohyoid
muscle
• Floor : infont : the hyoglossus muscle ( above ) and the
thyrohyoid muscle (below)
• Behind: the middle constrictor muscle of the pharynx
(above ) and the inferior constrictor muscle of the
pharynx (below )

9. External carotid
artery
Common carotid artery
Internal
carotid
artery

10. Contents of the Carotid triangle
• 1- The carotid sheath and its contents :
• - common carotid artery : in the lower part of
the triangle .
• - internal carotid artery : in the upper part of
the triangle .
• Internal jugular vein : lateral
• Vagus nerve : between the artery and the vein
but in a more posterior plane .

11. • 2- the external carotid artery : gives most of its
branches in the carotid triangle ( superior thyroid
artery ,lingual artery ,facial artery , ascending
pharyngeal artery and occipital artery )
• 3- hypoglossal nerve
• 4- Descendes cervicalis (C2,3) anterior to carotid
sheath.
• 5- sympathetic trunk adherent to the posterior
wall of carotid sheath

12. Muscular triangle
• Outlines :
• Infront : midline of the neck
• Behind and above :superior belly of omohyoid
muscle
• Behind and below : the sternomastoid muscle
It contains the infrahyoid muscle contain
toss ,,,thyrohyoid
,,omohyoid,sternohyoid,sternothyroid

13. Submental triangle
• Outlines :
• Infront : symphysis menti of the mandible
• On each side : the anterior belly of digastric
muscle
• Behind ( base ) : the hyoid bone
• Floor : parts of the mylohyoid muscles as they
meet each other in the median plane
• Contains …………………………
• 1- submental lymph nodes
• 2- beginning of the anterior jugular vein

14. Deep Neck Space Anatomy
• Space Involving Entire Length Of Neck
• Space Limited To Above The Hyoid Bone
• Space limited To Below The Hyoid Bone

15. Space Involving Entire Length Of Neck
1. Retropharyngeal Space
2. Danger Space
(Prevertebral Space)
3. Paravertebral Space
4. Carotid Sheath Space

16. Retropharyngeal Space
• Between visceral division
of middle layer and alar
division of deep layer
• Extend from skull base to
T2 level
• Midline raphae
• More commom in children
due to presence of
retropharyngeal node

17. Danger Space
• Between alar division and
prevetebral division of deep
layer (locate posterior to
retropharyngeal space)
• Extend from skull base to
diaphram
• No midline raphae
• Infection spread from neck
to posterior mediastinum
easily

18. Paravertebral Space
• Between prevertebral division
of deep layer and vertebral
bodies
• Extend from skull base to
coccyx
• Infection in this space is rare
and spread slowly due to
compact connective tissue

19. Carotid sheath Space
• Made up from all deep
cervical fascia
• Infection from any deep
fascia can spread to this
space (lincoln High
way)

20. Space Limit To Above The Hyoid Bone
1. Parapharyngeal Space
2. Submandibular Space
3. Masticator Space
4. Temporal Space
5. Parotid Space

21. Parapharyngeal Space
(Lateral phryngeal Space)
(Pharyngomaxillaly Space)
Boundary
• Superiorly : Skull base
• Inferiorly : Hyoid bone
• Laterally : Medial pterygoid m.
• Medially :Buccopharyngeal fascia
• Anteriorly : Submandibular space
• Posteromedialy : Prevertebral fascia &
retrophryngeal space

22. Submandibular Space
Divided into 2 spaces by
mylohyoid m.
1. Sublingual space (above
mylohyoid m.)
2. Submaxillaly space (below
mylohyiod m.)
• These 2 spaces can
communicate each other by
mylohyoid cleft

23. Masticator Space
• Between masticator m. and
superficial layer of deep
cervical fascia
(Masticator m. = massestor
m.,medial and lateral
pterygoid m. and
temporalis muscle)
• Locate anterior and lateral
to parapharyngeal space

24. Parotid Space
• Between parotid gl. and
superficial layer of deep
cervical fascia
• Infection can spread easily
to parapharyngeal space
due to incompleted encircle
at upper inner surface of
parotid gl.

25. Space Limit To Below The Hyoid Bone
Anterior Viseral Space
(Pretracheal Space)
• Between trachea,
esophagus and middle
layer of deep cervical fascia
• Extend from hyoid bone to
superior mediastinum