Anatomy Week 6 Flashcards
(97 cards)
1
Q
Name the components of the eye
A
- Bony orbit
- Eyelids and lacrimal apparatus
- Eye ball
- Six extraocular muscles
2
Q
What are orbits
A
Bilateral bony cavities in the facial skeleton shaped like hollow quadrangular pyramids
3
Q
How are the medial and lateral walls situated in the orbits bases
A
- Medial walls are parallel and lateral walls are at 90 degree
4
Q
What is the function of eyelids
A
Bound the orbits and control exposure of the eyeball
5
Q
What is the function of extrocular muscles in the orbital region
A
Position the eyeballs and raise the superior eyelids
6
Q
What does the orbital fascia surround
A
The eyeballs and muscles
7
Q
What is Conjunctiva in the orbital region
A
A mucous membrane that lines the eyelids and anterior eyeballs
8
Q
What is the function of Lacrimal apparatus
A
Lubricates the eye
9
Q
What is the remaining space in the orbits filed with
A
Orbital fat
10
Q
What is the shape/structure of orbits
A
- Hollow quadrangular pyramids with a base , four walls and an apex
11
Q
What is the base if the orbit outlined by
A
Orbital margin
12
Q
Name the 4 walls orbits contain
A
- superior wall
- Medial wall
Inferior wall
Lateral wall
13
Q
What is the superior wall(roof) of the orbit formed by
A
- Formed by mainly the orbital part of the frontal lobe
+ the lesser wing of the sphenoid
14
Q
What does the superior wall of the orbits contain
A
Lacrimal fossa
15
Q
What is the medial wall formed by
A
- Orbital plate of the ethmoid bone along with contributions from the frontal process of the maxilla, lacrimal and sphenoid bones
16
Q
What is the inferior wall of the orbit formed by
A
Maxilla and partly the zygomatic and palatine bones
17
Q
Explain the structure of the medial wall of the orbits
A
- Paper thin
18
Q
Explain the structure of the lateral wall of the orbits
A
- The strongest and thickest wall
19
Q
What is the lateral wall of the orbits formed by
A
Formed by the frontal process of the zygomatic bone and the greater wing of the sphenoid
20
Q
Where is the Apex located
A
At the optic canal in the lesser wing of the sphenoid
21
Q
What is the periorbita
A
- Periosteum of the orbit
22
Q
What are the bones forming the orbit lined with
A
Periorbita
23
Q
What is the periorbita continous with(5)
A
-Periosteal layer of dura mater
-The periosteum covering the cranium
-The orbital septa
-The fascial sheaths of the extraocular muscles
-The orbital fascia
24
Q
What is the function of the eyelids and lacrimal fluid
A
-Protect the cornea and eyeballs from injury and irritation
25
Explain the structure of the upper and lower eyelids
- They are movable folds of skin
26
What is the eyelids externally covered by + internally
Externally covered by skin and internally by the palpebral conjunctiva
27
What are Tarsal plates
- Dense connective tissues that provide suppot to the eyelids
28
What do Tarsal plates contain + function of contents
- Tarsal glands, that lubricate the eyelid edges
29
What is the function of the Orbicularis oculi muscle in the eye
- Closes the eye
30
Name the muscle that closes the eye
Orbicularis oculi
31
What is the function of the Levator palpebrae superioris muscle
Lifts the upper eyelid
32
What is the function of the orbital septum
- Connect the tarsal plates to the margins of the orbit + holds orbital fat in place
33
Where are eyelashes located
On the margins of the eyelids
34
What are palpebral commissures
Junctions of the superior and inferior eyelids
35
What is the function of the medial palpebral ligament
-What does it connect
Conects the tarsi to the medial orbit , providing attachment for the orbicularis oculi
36
What is teh function of the lateral palpebral ligament
-What it attaches
IT attches the tarsi to the lateral margin of the orbit
37
Where is the lacrimal Gland located
It is located in the lacrimal fossa of the orbit
38
What does the lacrimal gland produce
Tears
39
What stimulates tear production
Secretomotor parasympathetic fibers from the facial nerve
40
What drains tears into the nasal cavity
Nasolacrimal duct
41
Name the 2 palpebral ligaments
Medial palpebral ligament
Lateral palpebral ligament
42
What is the Lacrimal fluid secreted through
- 8-12 Excretory ducts into the superior conjunctival fornix
43
What does blinking do to the lacrimal fluid
- It spreads the fluid over the cornea, pushing debris like dust towards the medial angle of the eye
44
Where does the lacrimal fluid drain through + what action moves it
- Capillary action moves the fluid into the lacrimal canaliculi via the lacrimal puncta
45
What constricts blood vessels
- sympathetic fibers
46
What causes blood shot eyes
When the conjunctiva appears colourless until its vessles dilate due to irritation
47
What can hyperemia( increase in blood flow) result from
Irritation
48
Inflammation and swelling can occur in the eyelid glands due to what?
Infection or duct obstruction
49
What does obstruction of the ciliary glands cause
- causes a painful red swelling
50
What does obstruction of sebaceous glands form
- Obstruction of the sebaceous glands form chalazia (cyst)
51
In the Middle ear what is the tympanic cavity
Air filled space in the temporal bone
52
In the middle ear what does the auditory tube connect + why
Connecs the middle ear to the pharynx , equalizing air pressure
53
What does the auditory ossicles transmit
- Vibrations from the tympanic membrane to the internal ear W
54
In the middle ear what do the muscles protect the inner ear from
Loud sounds
55
Name the layers of the eye
-Outer fibrous layer
-Middle vascular layer
-Inner neural Lyer
56
What does the outer fibrous layer include
sclera and cornea
57
Explain the structure of the sclera + function
- White part of the eye
-provides shape,structure and site for muscle attachment
58
Explain the structure of the cornea
Transparent anterior part
59
What dose the middle vascular layer contain
- Choroud, ciliary body and iris
60
Give a characteristic of the choroid + what does it norusih
- Highy vasculr
-Nourishes the retina
61
What does the ciliarybody connect
- choroid to the iris
62
What does the ciliary body contain + what does it secrete
- Contains ciliary muscle
-Secrets aqueous humor
63
What is the iris
Coulored part of the eye
64
What does the iris contain
-The pupil
65
Name the muscles in the middle vascular layer+ their functions
sphincter pupillae- constricts pupil
dilator pupillae, dilates pupil
66
What does the inner layer contain
retina
67
Name the 2 parts the inner neural layer
optic part
non optic part
68
Which of the 2 parts in the neural layer is light sensitive
optic part
69
What is the center of the fovea + what does it lack
foveola,lacks capillaries
70
Name the path of light to Retina
-Cornea
-Aqueous humor
-Lens
-Vitrous body
71
What doe rods function in
Dim light and nigth vison
72
What do cones function in
colour vison and for high visual acuity
73
What happens in presbyopia + what it leads to
-The lends become thicker and less elastic+ thicker
-Leads to dificuly focusing on near objects`
74
What are cataracts
When the pens become cloudy due to opacities
75
How is cataracts treated
- Cataract extraction and introcular lens implant
76
What does extrascapular cataract extraction involve
- Removal of the lens but leaving the capsule
77
What does intrasccapular cataract extraction involve
The lens and capsule both being removed and placing an anterior lens in the anterior chamber
78
Name the 2 different types of cataract extraction
Extracapsular
intracapsular
79
What is Glaucome caused by
Blocked aqueous humor outflow
80
What does glaucome lead to
Increased intraocular pressure
81
What is the main artery for the orbit + what it branches intoc+ the function of that
- Opthalmic artery branches into
- Central retinal artery , which supply the retina
82
Name the veins in the orbit
Supeior and inferior opthalmic veins
83
Where do the veins in the orbit drain into
- cavernous sinus
84
Name the 6 cranial nerves in the orbit + NUMBERS+ function
- Optic nerve-1-vision
-Oculomotor-2-pupil constriction
-Trochlear-4-supeiror oblique
-Opthalamic-V1-sensory
-Abducent-6
-Facial- 7- lacrimal gland secretion
function:
85
What is the function of the sympathetic nerve from cartoid plexus in relation to the eye - what it dilates+ innervates
-Dilutes pupil + innervates ciliary body
86
What is the function of the parasympathetic from cranial nerve 3
Constricts pupil and accomodation of ciliary body
87
Explain the function of the parasympathetic from cranial nerve 7
- Tear secretion
88
What is horner syndrome
-Distrubition of sympatehtic pathway in thr neck
89
What are symptoms of horners syndrome
-drooping eyelid
-sunken eye
-pupil constriction
90
What are the effects of an oculomotor nerve injury
- The eye deviates down and out +
- pupil dilates
91
What is the optic nerve formed by
Axons of ganglion cells in the retina
92
What is the optic nerve myelinated by
Oligodendoryctes
93
What does the optic nerve exit the orbit via
Via the optic canal
94
Where is the optic chiasma located
Near the anterior wall of the the 3rd ventricle
95
Name 2 fibers the optic chiasma contains
- Nasal retinak
-Temporal retinel
96
What does the optic tract continue from
Optic chiasma
97
What is the lateral Geniculate body part of
Thalamus
