Brainscape's Knowledge GenomeTM


Top Flashcards (Certified)
All Flashcards

Sensory > Ophthalmology > Flashcards

Ophthalmology Flashcards

1
Q

Sclera

A

Hard, inflexible white of the eye made of collagen

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

Uvea

A

Inner vascular layer containing the iris, ciliary body and choroid

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

Retina

A

Further inner layer that converts information into images

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

Lens

A

Causes image to be inverted

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

What type of vision does a visual acuity test check?

A

Central vision

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

Visual field

A

The portion of the external environment of the observer wherein the steadily fixating eye can detect visual stimuli

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

Size of monocular visual field

A

Vertical axis: 135˚ –60˚ superior field (limited because of brow) and 75˚ inferior field
Horizontal axis: 160˚ – 60˚ nasal field (limited because of nose) and 100˚ temporal field

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

Size of binocular visual field

A

180˚ in total with 120˚ overlap between right and left eye, allowing depth perception

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

Fovea

A

Centre of macula (1.5 mm diameter)

Peak in number of cones, therefore responsible for visual acuity

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

Macula

A

5 mm ring around fovea in the temporal retina

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

Foveola

A

Centre of fovea

0.2 mm diameter

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

Vertical meridian

A

Imaginary line that goes through the fovea

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Nasal and temporal retina

A

Nasal retina is medial, temporal retina is lateral
The left temporal retina and the right nasal retina pick up the left nasal and right temporal visual fields and project to the left hemisphere
The right temporal retina and the left nasal retina pick up the right nasal and left temporal visual fields and project to the right hemisphere

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Where is the defect in a patient with central scotoma?

A

In the temporal retina of the affected eye

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

Where is the defect in a patient with bitemporal hemianopia?

A

At the optic chiasm where the optic nerves meet, affecting both nasal retina tracts and inhibiting the temporal visual field in both eyes

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

Where is the defect in a patient with homonymous hemianopia?

A

Anywhere in the optic tract downstream of the optic chiasm, causing visual field loss on same side of both eyes
E.g., if a lesion in the left optic tract occurred, both eyes would lose the left visual field (nasal retina affected in the right eye affecting the temporal visual field and temporal retina affected in the left eye affecting the nasal visualfiel)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

Extra-ocular muscles

A

Superior, inferior, lateral and medial rectus

Super and inferior oblique

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

Nerves that supply extra-ocular muscles

A

All by oculomotor nerve, except:
Lateral rectus, which is supplied by abducent nerve
Superior oblique, which is supplied by trochlear nerve

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

7 bones that make up the orbit

A 
Frontal
Sphenoid
Lacrimal
Ethmoid
Maxillary
Zygomatic
Palatine
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

Obicularis oculi

A

Muscle that closes eyelid

Controlled by facial nerve

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

Levator palpebrae

A

Muscle that opens eyelid

Controlled by oculomotor nerve

22
Q

Assembly of the eye

A

Cornea: Contains ganglion cells attached to processing and connecting cells and further in these are connected to photoreceptor rods and cones
Rods at a higher concentration in the peripheral retina and cones at a higher concentration near the fovea
Rods and cones attach to the retinal pigment epithelium at the back of the eye

23
Q

Physiological blind spot

A

The optic nerve sits in the nasal retina but has no ability to detect light. This creates a blind spot normally filled in by the temporal retina of the other eye

24
Q

Tear film

A

About 10 mincrons think on front of eye
Consists of oil from tarsal gland (stops evaporation of fluid from eye surface), an aqueous component from the lacrimal gland and mucin

25
Ptosis
Dysfunction of levator papebrae superiosus | Can be due to a multitude of reasons including congenital, mechanical, traumatic, neurogenic, etc.
26
Oculomotor nerve palsy
Supplies LPS, therefore upper lid ptosis Pupil dilated Eye looks to left because only muscles working are now superior oblique and lateral rectus
27
Horner's syndrome
Damage to sympathetic nerves in the face causes ptosis, pupil constriction and anhydrosis
28
Function of tears
Lubrication Oxygen transmission Vision clarity
29
Function of conjunctiva
Oxygen transmission Tear production Defence and protection
30
Function of eyelids
Protection Tear film production and distribution Tear flow and drainage
31
Function of cornea
Refractive surface of fixed power Oxygen transmission Potection
32
Function of sclera
Protection Ocular rigidity Attachment of extra-ocular muscles
33
Function of lens
Refractive surface of variable power
34
Function of iris/pupil
Restriction of light to retina | Reduction of light scatter
35
Function of ciliary body
Attachment of lens | Production of aqeuous humour
36
Aqueous humour
Transparent, watery fluid similar to plasma, but containing low protein concentrations Secreted from ciliary epithelium in the eye for nutrient supply to lens and cornea
37
Choroid
Provides oxygen and nutrition to outer retina
38
Vitreous chamber
Storage of vitreous humour which maintains ocular shape and protects ocular structures during trauma
39
Function of retina
Provides visual sensation and converts light images into nerve impulses
40
Function of optic nerve
Transmits electrical signals to the brain via the optic nerve
41
Pathway of visual signal
Light filtered by iris/pupil and image inverted by lens Retina converts light image into a nerve impulse which travels through: Optic nerve Optic chiasm Optic radiation Lateral geniculate nucleus Ending up at the occipital cortex
42
Rods
Process signals within visual images seen at low light levels Found more in the peripheral retina and are responsible for the detection of peripheral movement
43
Cones
Responsible for the detection of colour and fine details, particularly in high levels of light More concentrated in the central visual field
44
Form/spatial vision
Clinically measured by visual acuity which varies with contrast, brightness, eccentricity and the testing procedure Reflects rod/cone distribution
45
Colour vision
Hue, saturation, brightness and colour interactions indicative of cone function and associated processing of visual signal May be useful in early detection of disease
46
Curvature of the cornea
Focuses light Formed from collagen lamellae that run parallel to surface of eye and underneath collagen formed orthogonally to each other for strength Needs to be kept in a state of relative dehydration because hyaluronic acid is hydrophilic
47
Keratoconus
A physiological difference where the curvature of the eye looks more oblong Can be genetic or environmental e.g. eye rubbing
48
Types of cells in the retina
``` Photoreceptors Horizontal cells Bipolar cells Amacrine cells Ganglion cells Mueller cells ```
49
Retinal blood supply
Consists of a dual supply: Choroidal to the outer retina and central retinal artery to the inner retina No blood vessels around the fovea because they disturb visual acuity
50
Accommodation
Focusing on something closer, which requires more refraction. Gets worse as we get older, causing presbyopia, a type of long-sightedness
51
Cataracts
Lens clouding Decreased visual acuity Diagnosis by ophthalmoscope and slit lamp

Sensory (9 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2025 Bold Learning Solutions. Terms and Conditions