ct and mri of head and neck

2. Five Bones:
• Ethmoid - CP
• Sphenoid-
GW+LW
• Occipital
• Temporal- paired
• Frontal-paired

3. • Anterior
• Middle
• Posterior

4. •
•
Anterior
• Frontal bone: frontal
sinus,supra-orbital
foramen
Posterior
• Post. edge of lesser
wing sphenoid and its
ant. Clinoid processes
–
–

5. • Anterior
• Posterior edge of lesser
wing of sphenoid
• Posterior
• Post-sup edge of
petrous temporal bone

6. •
•
Anteriorly
– Post-sup edge of petrous
temporal bone
Posteriorly
– it is enclosed by the
occipital bone.
• Laterally
– portions of the squamous
temporal and mastoid part
of the temporal bone form
its walls.
• It contains the brainstem
and cerebellum.

7. Temporal Bone
Temporal bone- petrous
portion
Sphenoid Bone
Occipital Bone
Key Fissures
• Petro-sphenoidal fissure
•Petro-occipital fissure
Key Sutures
• Sphenosquamous Suture
• Occipitomastoid Suture

9. FORAMEN OVALE
FORAMEN SPINOSUM

10. CAROTID CANAL
JUGULAR FORAMEN

11. IAC
INTERNAL AUDITORY CANAL
CAROTID CANAL
OSSICLES
MALLEUS
INCUS

13. Foramen rotundum-
higher level
Pterygopalatine
fossa
Foramen ovale
Foramen spinosum
Sphenoid spine-
lower level
Petro-occipital
fissure
Pterygoid
canal
f. lacerum

14. Foramen Spinosum
• Middle meningeal artery/vein
• CV V3, recurrent branch
• Lesser superficial petrosal nerve
Foramen Ovale
• CN V3
• Lesser petrosal nerve
• Accessory meningeal artery
• Emissary veins

15. Foramen Lacerum
•Ascending pharyngeal
artery- meningeal branch
• Nerve of pterygoid canal
Vidian Canal
• aka pterygoid canal
•Pterygopalatine fossa - foramen
lacerum
• Vidian nerve
• Vidian artery

16. Foramen rotundum
• CN V2
• Artery of foramen rotundum
• Emissary veins

17. *
Foramen magnum
• Medulla oblongata
• Vertebral arteries
• Anterior/Posterior spinal
arteries
Hypoglossal canal
• CN XII
• Hypoglossal artery
*

18. Jugular Foramen
•Pars nervosa: CN IX, inferior
petrosal sinus
•Pars vascularis: CN X, XI,
jugular bulb
*
* Carotid canal

19. Pterygopalatine Fossa
• Pterygopalatine ganglia V2
• Pterygopalatine plexus
• Communicates with:
Inferior orbital fissure
Orbital apex
Sphenopalatine foramen
Pterygomaxilary fissure
Foramen rotundum
Vidian canal
Greater/lesser palatine canals and foramina

20. Receives:
Drains via:
Superior opthalmic vein
Inferior opthalmic vein
Sphenoparietal sinus
Petrosal sinuses
Basilar plexus
Connection:
Contains:
Pterygoid plexus
Circular sinus
CN III, IV, V1, V2, VI
Cavernous Sinus
Meckel’s Cave
• Posterior aspect of cavernous sinus
• Gasserian ganglion (sensory root ganglion of CN V)

21. Superior Orbital Fissure
• CN III, IV, V1, VI
• Middle meningeal artery- orbital branch
• Recurrent meningeal artery
• Superior opthalmic vein
Inferior Orbital Fissure
• Infraorbital artery, vein, and nerve (V2 branch)
Optic Canal
• Optic nerve
• Opthalmic artery

27. Described in relation to the hyoid bone.
▶ Suprahyoid Spaces.
▶ Infrahyoid Spaces.
▶ Spaces extending up to the entire length of
the neck.

28. ▶ Carotid Space.
▶ Retropharyngeal Space.
▶ Danger space.
▶ Peri-vertebral Space (prevertebral component & para-
spinal component) .

30. ▶ Sublingual Space.
▶ Submandibular Space.
▶ Buccal Space.
▶ Masticator Space.
▶ Parotid Space.
▶ Pharyngeal mucosal Space.
▶ Parapharyngeal Space

33. ▶ Visceral Space.
▶ Anterior cervical
Space.
▶ Posterior
cervical Space.

35. ▶ Paired tubular structure
traversing SHN and IHN
▶ Skull base to superior
mediastinum
▶ Lateral to RPS
▶ Enveloped by carotid sheath : all
3 layers of DCf
▶ Contents : SHN – ICA IJV ,
CN9-12,
:IHN - CCA, IJV ,
CN10 trunk ( vagus)

37. ▶ Extent : Skull base to T4 level
▶ 2 parts
▶ Ant : True RPS
▶ Post : Danger space
▶ Contents :
▶ SHN : LN and fat
▶ IHN : Fat
▶ pathway for spread of
infections / tumors into the
mediastinum from the neck.

38. Relations
▶ The retropharyngeal space is:
 anterior to the danger space
 posterior to the pharyngeal
mucosal space
 anteromedial to the carotid space
 posteromedial to the
parapharyngeal space

40. ▶ Extends from the skull base up to the diaphragm
▶ Posterior to the RPS.
▶ Bounded by theAlar fascia anteriorly and Prevertebral fascia posteriorly.
▶ Content : loose areolar tissue which provides easy pathway for the spread of infections.
▶ In healthy patients, it is indistinguishable from the retropharyngeal space. It is only
visible when distended by fluid or pus, below the level of T1-T6, since the
retropharyngeal space variably ends at this level.

42. ▶ Posterior midline space
of SHN and IHN
▶ Enclosed by deep layer
of DCF
▶ Extent : base of skull to
level of coccyx
▶ 2 compartments :
Prevertebral and
Paraspinal

44. Extent : Above the mylohyoid
muscle
Contents : Sublingual
and their
hypoglossal
ducts
muscle
gland
, LNs,
, lingual
artery and vein ,hypoglossal N
and deeper portion of
submandibular gland.

46. ▶ Extend : Mylohoid superiorly & hyoid
bone inferiorly.
▶ Communicates freely with sublingual
space.
▶ Contents : superficial portions of the
Submandibular gland,submental and
submandibular LNs, facial artery and
vein, fat and ant belly of digastric.

47. ▶ Extent :
Medially - Buccinator and
maxillary alveolar ridge
Post Laterally : Masticator space
▶ Contents: Buccal fat pad

49. ⚫ Formed by splitting of the
SLDCF.
⚫ Extends from skull base to
the inferior edge of the
mandible.
⚫ Contents: mandible, muscles
of mastication, and
mandibular division of the Vth
nerve.

50. ▶ Boundary : Investing fascia(SLDCF) splitting at the angle of mandible.
▶ Extends : Superiorly external acoustic meatus
Inferiorly up to the mandible.
▶ Contents: Parotid Gland, proximal part of the parotid duct, intraparotid
lymph nodes and vessels.
▶ Parotid gland is divided by facial nerve into superficial and deep.

51. 1-POST STYLOID PARAPHARYNGEAL
SPACE
2-MASTICATOR SPACE
3-CAROTID SPACE
4-PAROTID SPACE
5-PRE STYLOID PARAPHARYNGEAL SPACE
6& 7-RETROPHARYNGEAL AND DANGER
SPACE

54. ▶ The visceral space extends from the hyoid bone to the superior
mediastinum (level of aortic arch / T4), and is surrounded by the
middle layers of the deep cervical fascia.
▶ Contents
• thyroid gland
• parathyroid gland
• oesophagus
• larynx
• hypopharynx
• trachea
• recurrent laryngeal nerve
• lymph nodes (level VI)

57. Superiorly-Base of skull including posterior part of body of sphenoid and
the basilar part of the occipital bone.
Inferiorly-pharynx continues with oesophagus at the level of 6th cervical
vertebra/ lower border of cricoid cartilage.
Posteriorly-Prevertebral fascia separating it from cervical spine
Anteriorly-Communication with Nasal cavity, Oral cavity, and Larynx.

58. ▶ The nasal part – NASOPHARYNX/ EPIPHARYNX
(extends from base of skull to soft palate)
▶ The oral part – OROPHARYNX
(extends from lower border of soft palate to upper
border of epiglottis)
▶ The laryngeal part – LARYNGOPHARYNX/
HYPOPHARYNX
(extends from upper border of epiglottis to lower
border of cricoid cartilage)

60. Roof- Basisphenoid and Basiocciput.
Posterior wall- Arch of Atlas vertebrae covered by prevertebral muscles and
fascia.
Anterior wall- Posterior nasal apertures (Choanae).
Lateral wall on both sides
- Opening of Eustachian Tube
-Tubal opening bounded by Tubal elevation/Torus tubarius
-Fossa of Rosenmuller or Lateral/Pharyngeal Recess
Inferiorly- It communicates with oropharynx

64. ▶ Above- communicates with nasopharynx through nasopharyngeal isthmus.
▶ Below- opens into laryngopharynx.
▶ Anterior wall-
upper part- oropharynx communicates with oral cavity through oropharyngeal
isthmus/ Isthmus of Fauces.
lower part- base of tongue
- lingual tonsils
- valleculae
▶ Posterior wall- Third cervical vertebrae.
▶ Lateral wall- Palatine/Faucial tonsil
- Anterior pillar (Palatoglossus muscle)
- Posterior pillar (Palatopharyngeus muscle)

71. Lower part of pharynx situated behind and partly on sides
of the larynx.
Hypopharynx lies opposite to 3rd, 4th, 5th, 6th cervical
vertebrae.
Clinically it is divided into 3 regions-
1. Pyriform Sinus (fossa)
2. Post-cricoid region
3. Posterior Pharyngeal wall

75. ▶

77.  The supraglottic division:
From the superior-most tip of the epiglottis -to
vestibular folds
 The glottis:
Space between vestibular folds and vocal
folds
 The subglottic region
From vocal folds -to the inferior portion of the
cricoid cartilage.

79. Supraglottic level
▶ The larynx is anterior to the piriform sinuses, separated from them by
the aryepiglottic folds.
82

81. SG 85

82. 86

83. ▶ A complete ring of cartilage is seen at this level –thyroid
cartilage anteriorly & lamina of the cricoid &arytenoid
cartilages posteriorly.
▶ The anterior fusion of the vocal cords is known as the
anterior commissure and is very thin when the cords are
abducted. Similarly, the posterior commissure, which is
seen between the arytenoids
▶ The larynx is elliptical in shape at the level of the true
cords and triangular at the level of the false cords, which
are at a slightly higher level.
89

85. G 92

86. ▶ Just below the cords the
larynx
lamina
is elliptical. The
of the cricoid is
with the
membrane
posterior,
cricothyroid
anterior.
▶ At a lower level the larynx is
more circular and the cricoid
forms a complete ring. Part
of the lobes of the thyroid
gland may be seen laterally,
93

88. 95

89. 97

90. 98

91. 99

92. 10
0

93. 10
1

94. 10
2

95. 10
3