Orbit and nasal cavity Flashcards

1
Q

Superior oblique muscle

A

Extra- ocular muscle responsible for:

  • Depression
  • Abduction

Innervated by Trochlear nerve

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Superior rectus

A

Extra- ocular muscle responsible for:

  • Elevation
  • Abduction

Innervated by CN3

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Inferior oblique

A

Extra- ocular muscle responsible for:
- Elevation

Innervated by CN3

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

Inferior rectus

A

Extra- ocular muscle responsible for:

  • Depression
  • Adduction

Innervated by CN3

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

Medial rectus

A

Extra- ocular muscle responsible for:
- Adduction

Innervated by CN3

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Lateral rectus

A

Extra- ocular muscle responsible for:
- Abduction

Innervated by CN6- abducens

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Levator palpebrae

A

Muscle responsible for the elevation and retraction of the eyelid.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

Orbits of the eye

A

Vertical
- Abduction and adduction

Transverse

  • Elevation
  • Depression

Anteroposterior
- Intorsion and extorsion

The natural orbit always leans outwards

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Bones of the nose

A

Frontal

2x nasal

2x maxilla

Septum

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Cartilage of the nose

A

Lateral

Major and minor alar

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Internal projections of the nasal cavity

A

Superior, middle and inferior conchae

  • directs flow of air
  • warms the air

Lined with epithelium

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Olfaction

A

‘Smelling’

Mechanism:

  • Odiferous gases in the air are dissolved in mucosal fluid secreted by epithelium
  • Conchae help to direct air
  • Odiferous gases are sensed by receptors connected to CN1.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Nervous supply to the nose

A
  • Olfactory, CN1
  • CN V1, ophthalmic
  • CN V2, maxillary
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Blood supply to nose

A

Supplied by branches from:

  • Ophthalmic
  • Maxillary
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Frontal paranasal sinus

  • Drainage
  • Innervation
A

Located on the frontal bone
- Drains into the frontonasal duct–> middle nasal meatus

Innervation
- Supraorbital nerve [from frontal nerve, CN V1]

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Ethmoidal air cells

  • Drainage
  • Innervation
A

Located within the ethmoidal bone

Drainage:
- Anterior and middle ethmoidal sinus—-> drains into middle meatus

  • Posterior—> into superior meatus

Innervation
- Nasocillary nerve [CN V1]

17
Q

Sphenoid paranasal sinus

  • Drainage
  • Innervation
A

Located within the sphenoid bone

  • Drains into the spheno-ethmoidal recess–> above the superior concha

Innervation
- Branch of nasocillary nerve [posterior ethmoidal], CN V1

18
Q

Maxilla paranasal sinus

  • Drainage
  • Innervation
A

Located within the maxilla bone
- Drains into middle meatus

Innervation

  • Superior alveolar nerve [CN V2]
  • Infraorbital nerve [CN V2]
19
Q

CN II

  • Type
  • Exit
  • Innervation
A

Optic nerve
- Sensory

Exits- Optic canal

Innervates:
- Vision [transmits visual information from the retina]

20
Q

Eye anatomy

A

Outer layer

  • Sclera [eye white]
  • Cornea [avascular]

Middle:

  • Vascular layer
  • Iris

Inner:
Retina

Posterior chamber: Below lens
Anterior chamber: Above lens

21
Q

Bones of the orbit

A
Nasal
Lacrimal
Ethmoidal
Frontal
Sphenoid
Temporal-Zygomatic
Maxilla
22
Q

CN III

  • Type
  • Exit
  • Innervation
A

Oculomotor
- Somatic motor

Exit: Superior orbital fissure

Innervation: Extra-ocular muscles

  • Superior rectus
  • Medial rectus
  • Inferior rectus
  • Inferior oblique

Ciliary body and sphincter pupillae
- Via parasympathetic ciliary nerve.

23
Q

CN IV

  • Type
  • Exit
  • Innervation
A

Trochlear nerve
- Somatic motor

Exits superior orbital fissure

Innervates superior oblique muscle [Depression + abduction]

24
Q

CN VI

  • Type
  • Exit
  • Innervation
A

Abducens nerve
- Somatic motor—-> Lateral rectus [abduction]

Exits superior orbital fissure

25
Q

Anosmia

A

Loss of the sense of smell\

Can be temporary [Mucus
filled from a cold] or permanent [Trauma, Parkinson’s abscess].

26
Q

Blood supply to the eye [3]

A

Ophthalmic [From Internal carotid]

Infra-orbital [From maxillary]

Central retina [From ophthalmic]

27
Q

Inability of specific eye movements- clinical consideration

A

Depression= Problem with CN 3/ CN 4

Elevation= CN3

Abduction= CN 3/6

Adduction = CN3

28
Q

Pupil dilation [blown pupil]- clinical consideration

A

Indicates impairment of CN3

- CN3 supplies sphincter pupillae via parasympathetic fibres

29
Q

Ptosis

A

Drooping eyelid

Indicates impairment of CN3
- CN3 innervates levator palpebrae [which opens eyelids]

30
Q

Aneursym in cerebral artery affects CN…

A

3

31
Q

An orbital fracture can impair CN…

A

4

32
Q

Cavernous sinus lesion can impair CN…

A

6

33
Q

Lacrimal apparatus

A

Enables crying.

  1. Lacrimal gland secretes lacrimal fluid.
  2. Lacrimal fluid flows into lacrimal papilla
  3. Fluid enters lacrimal sac than inferior meatus via naso-lacrimal duct.
34
Q

Nervous supply to lacrimal apparatus

A

Secremotor
- Parasympathetic—-> follows CN VII

Vasconstrictive
- Sympathetic—-> follows interal carotid from superior cervial ganglion

35
Q

Parasympathetic supply to lacrimal gland

A

Facial nerve at internal acoustic meatus travels
- Joins with lacrimal nerve [CN V1] into gland

CN VII—-> Greater petrosal nerve—-> Deep petrosal nerve [from internal carotid plexus]—–> Nerve of pterygoid canal synapses at ganglion