Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

x 2nd Year Medicine > Opthamology > Flashcards

Opthamology Flashcards

1
Q

What are the rods of the eye responsible for?

A

Night/peripheral vision

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

What are the cones of the eye responsible for?

A

Detailed/colour vision

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

What cranial nerves are involved in some way with the eye?

A

2-7

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

As a general rule in ophthalmology if a bacteria shows on gram stain to be a gram +ve cocci, what is it?

A

Strep/Staph

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

As a general rule in ophthalmology if a bacteria shows on gram stain to be a gram -ve cocci, what is it?

A

neisseria

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

As a general rule in ophthalmology if a bacteria shows on gram stain to be a gram -ve cocci-bacilli, what is it?

A

H.influenzae

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

As a general rule in ophthalmology if a bacteria shows on gram stain to be a gram -ve bacilli, what is it?

A

pseudomonas

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

What are the common causes for bacterial conjunctivitis in neonates?

A 
Staph aureus
Neisseria gonnorrhoea (from mother)
Chlamydia trachomatis (from mother)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What should be done for all cases of neonatal bacterial conjunctivitis?

A

Refer immediately to ophthalmology

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

In all ages except from neonates, what are the commonest causes of bacterial conjunctivitis?

A

Staph aureus
Strep pneumoniae
H.influenzae (esp. in children)

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

What is the treatment for bacterial conjunctivitis?

A

Swab and culture for sensitivity

Topical antibiotic = chloramphenicol qds

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

When should chloramphenicol be avoided?

A

In a patient with a history of allergy, or aplastic anaemia

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

Treatment bottles for bacterial conjunctivitis can be easily contaminated, what is a common contaminent?

A

Pseudomonas aeruginosa

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

What other bacterial causes should be considered in a bacterial conjunctivitis in contact lens users?

A

Pseudomonas aeruginosa

Acanthamoeba

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

What viruses commonly affect the conjunctiva?

A

Adenovirus
Herpes simplex
Herpes zoster

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

How would an adenovirus conjunctivitis present?

A

Red, swollen conjunctiva and watery eyes

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

How would a conjunctivitis caused by Herpes simplex present?

A

Small pustules in the lateral corner of the skin around the eye

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

How would a conjunctivitis caused by Herpes zoster present?

A

Eye involved in a shingles pattern (if tip of nose is affected then this indicated more serious eye involvement)

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

When should a chlamydial conjunctivitis be suspected?

A

More chronic history
Unresponsiveness to classical treatments
Bilateral
May of may not have genital symptoms

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

How would a chlamydial conjunctivitis present?

A

Watery, slightly red conjunctiva and sclera
Follicular nodules on the underside of the upper and lower eyelids (subtarsal)
If untreated may lead to subtarsal scarring which makes blinking painful and scratchy

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

How would a bacterial keratitis present?

A

A yellow, pussy nodule +/- white cells collecting at the bottom of the sclera (hypopyon)
If lies over pupil then may affect vision

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

How is bacterial keratitis treated?

A

Hospital admission for hourly eye drops

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

How would a herpetic keratitis present?

A

Dendritic ulcer which shows up on fluorescein studies
Eye is slightly watery
May be very painful and may recurr (less painful with each recurrence)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

What treatment should NEVER be given in herpetic keratitis and why?

A

Steroids - may cause corneal melt and perforation

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

How is herpetic keratitis treated?

A

Aciclovir

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

How would an adenoviral keratitis present?

A

Subepithelial infiltrates on the underside of the cornea which may blurred vision
Bilateral - usually following an URTI
Very contagious

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

How is an adenoviral keratitis treated?

A

Topical antibiotics to prevent secondary infection (if likely)
Steroids (if becomes chronic)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
28
Q

How would a fungal keratitis present?

A

Similar to bacterial but with a more gradual history

Usually after some form of trauma from vegetation

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
29
Q

How does orbital cellulitis present?

A 
Painful moving eyes
Proptosis
Often associated with paranasal sinuses
Pyrexia
Sight-threatening
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
30
Q

What investigation needs to be done in a patient presenting with orbital cellulitis?

A

CT - identification of orbital abscesses

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
31
Q

What are the common causative organisms of orbital cellulitis?

A 
Staph
Strep
Coliforms
H.influenzae
anaerobes
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
32
Q

How is orbital cellulitis treated?

A

Broad spectrum antibiotics and close monitoring

Abscess may require drainage if present

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
33
Q

What is endophthalmitis?

A

A devastating infection involving the entire globe

Endogenous or post surgery

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
34
Q

How does endophthalmitis present?

A

v. rapid onset and v. painful
v. red eye
decreased vision which may be permanent

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
35
Q

What organisms are responsible for endophthalmitis?

A

Often conjunctival commensals

Staph epidermidis is most common

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
36
Q

How is endophthalmitis treated?

A

Intravitreal amikacin
Vancomycin
Topical antibiotics

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
37
Q

What is chorioretinitis?

A

Inflammation of the choroid and retina

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
38
Q

What can cause chorioretinitis?

A

Cytomegalovirus (CMV)

Toxoplasma gondii

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
39
Q

How does a CMV chorioretinitis present?

A

Retinal haemorrhage

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
40
Q

How does a toxoplasma gondii chorioretinitis present?

A

Protozoan infection causing a mild flu-like illness
May cause problems in immunocompromised patients
Causes cysts to form in the retina which may be sight threatening (if true then systemic therapy needed)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
41
Q

How are eye infections diagnosed?

A 
Swabs - bacterial, chlamydial, viral
Corneal scrapes - bacterial keratitis
Aqueous/vitreous collection for culture - endophthalmitis
Microscopy/culture - acanthamoeba
Serology - Toxoplasma gondii
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
42
Q

What treatments are used for bacterial conjunctivitis?

A

Chloramphenicol - all except pseudomonas aeruginosa
Fusidic acid - Staph aureus
Gentamicin - gram -ves (coliforms and pseudomonas aeruginosa)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
43
Q

How is chlamydial conjunctivitis treated?

A

Topical oxytetracycline

Adults may also need azithromycin for genital disease

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
44
Q

How is herpetic conjunctivitis treated?

A

Topical +/- oral antivirals (aciclovir)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
45
Q

How is bacterial keratitis treated?

A

Ofloxacin - most gram -ves (not strep. pneumoniae)

Gentamicin + cefuroxime - most gram -ves and +ves

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
46
Q

What is dacrocystitis?

A

A blockage in the lacrimal sac which has become infected and inflammed

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
47
Q

How is dacrocystitis treated?

A

Systemic antibiotics, then open duct

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
48
Q

Where is the choroid plexus found in the human adult brain?

A

3rd and 4th ventricles

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
49
Q

What makes up the blood brain barrier?

A

Endothelial cells in brain capillaries

  • capillary endothelium
  • basal membrane
  • perivascular astrocytes
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
50
Q

What is the function of the blood brain barrier?

A

Protection of the brain from common bacterial infections and toxins

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
51
Q

What is routinely measured in CSF samples?

A 
Proteins
Albumin
Immunoglobulin
Glucose
Lactate
Cellular changes
Specific antigen and antibody testing for infectious agents
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
52
Q

What is a colloid cyst?

A

A rare glioma often found at the interventricular foramen

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
53
Q

What is a pinealoma?

A

A tumour arising from the pineal gland in the midbrain - can often compress the cerebral aqueduct

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
54
Q

What are ependyomas?

A

5% of all gliomas, arising from ependymal cells lining the ventricles
Children under 5 are mostly affected by this

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
55
Q

Who do choroid plexus tumours usually affect?

A

Children under 10

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
56
Q

What is a ventricular haemorrhage?

A

Accumulation of blood in the ventricles from either haemorrhage in the brain with secondary rupture into the ventricles, rupture of an intracranial aneurysm, or other vascular malformations

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
57
Q

What is hydrocephalus?

A

Accumulation of CSF in the ventricular system, or around the brain.
Subsequent enlargement of 1 or more ventricles or increased CSF pressure

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
58
Q

What are the symptoms of hydrocephalus?

A

Headache, N+V, visual disturbances, lethargy and potentially coma

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
59
Q

How would normal pressure hydrocephalus present?

A

Triad of:
Dementia
Incontinence
Gait Disturbances

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
60
Q

How would normal pressure hydrocephalus present?

A

Triad of:
Dementia
Incontinence
Gait Disturbances

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
61
Q

What is idiopathic intracranial hypertension?

A

A mysterious condition mostly seen in obese females of child bearing age

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
62
Q

How does idiopathic intracranial hypertension present clinically?

A

Headache
Visual disturbances due to papilloedema
Increased CSF pressure but no signs of hydrocephalus

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
63
Q

How is idiopathic intracranial hypertension managed?

A

Weight loss, medications and potentially a VP shunt.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
64
Q

What is papilloedema?

A

A swelling of the optic disc due to increased ICP transmitter to the sub arachnoid space surrounding the optic nerve

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
65
Q

How may papilloedema present?

A

Enlarged blind spot
Blurriness
Visual obscurations
Loss of vision

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
66
Q

What is the aqueous humour?

A

A specialised fluid that bathes structures within the eye providing oxygen, metabololites and bicarbonate

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
67
Q

What is the function of the bicarbonate present in the aqueous humour?

A

buffers the H+ produced in the cornea and lens by anaerobic glycolysis

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
68
Q

How is aqueous humour produced?

A

By an energy dependent process in the epithelial layer of the cilliary body into the posterior chamber of the eye

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
69
Q

What is the route through which the aqueous humour flows?

A

Anterior chamber -> scleral venous sinus -> trabecular meshwork -> canal of Schlemm (situated in the angle between the iris and cornea iridocorneal angle

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
70
Q

What covers the ciliary body and posterior surface of the iris?

A

2 juxtaposed layers of epithelial cells:

  • a forward continuation of the pigment epithelium of the retina (PR)
  • an inner non-pigmented epithelial layer on top (NPE)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
71
Q

What covers the ciliary body and posterior surface of the iris?

A

2 juxtaposed layers of epithelial cells:

  • a forward continuation of the pigment epithelium of the retina (PR)
  • an inner non-pigmented epithelial layer on top (NPE)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
72
Q

What is formed in the epithelial cells covering the cilliary body, from the hydration of CO2 catalysed by Carbonic Anhyrase?

A

HCO3- and H+

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
73
Q

What happens to the HCO3- and H+ which are formed in the epithelial cells?

A

Transported across the basolateral membranes of PE cells in exchange for Cl- and Na+

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
74
Q

What is the result of the ionic exchange done in the epithelial cells?

A

Aqueous humour movement is accompanied by water movement

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
75
Q

How much aqueous humour is secreted per minute into the anterior chamber of the eye?

A

1-3ml

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
76
Q

How much aqueous humour in total lies in the posterior chamber?

A

60ml (completely replaced every 30 mins)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
77
Q

How much aqueous humour in total lies in the anterior chamber?

A

250ml (completely replaced every 120 mins)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
78
Q

Secretion and drainage of aqueous humour maintains the intra-ocular pressure at what level?

A

~17mmHg above the atmospheric level

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
79
Q

What caused raised IOP in glaucoma?

A

Increased secretion of aqueous humour compared to removal

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
80
Q

What drugs work to lower the IOP in glaucoma?

A

Carbonic anhydrase inhibitors (slow aqueous humour production)

  • Dorzolamide eye drops
  • Acetazolomide - oral (may cause acidosis)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
81
Q

What drugs work to lower the IOP in glaucoma?

A

Carbonic anhydrase inhibitors (slow aqueous humour production)

  • Dorzolamide eye drops
  • Acetazolomide - oral (may cause acidosis)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
82
Q

What type of glaucoma is most common?

A

Open-angle (symptomless) Slowly progresses and may cause permanent congestion and blindness

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
83
Q

What is open angle glaucoma caused by?

A

An obstruction to the aqueous outflow across the trabecular network

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
84
Q

What 4 things must happen in order for us to see an object?

A
  1. Pattern of object must fall on the vision receptors
  2. Amount of light entering the eye must be regulated
  3. Energy waves from photons must be transduced into electrical signals
  4. Brain must receive and interpret the signals
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
85
Q

What is the role of horizontal cells within the retina?

A

Receive input from photoreceptors and project this info to other photoreceptors and bipolar cells

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
86
Q

What is the role of amacrine cells in the retina?

A

Receive input from bipolar cells and project this info to ganglion cells, bipolar cells and other amacrine cells

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
87
Q

What is the role of photoreceptors?

A

Conversion of electromagnetic radiation to neural signals

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
88
Q

What type of resting membrane potential (Vm) do photoreceptors have?

A

Depolarised (+ve)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
89
Q

What happens to Vm when exposed to light?

A

Hyperpolarises

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
90
Q

Why is the Vm for photoreceptors +ve?

A

Due to the dark current - A cGMP-gated Na+ channel that is open in the dark and closed in the light

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
91
Q

A change in what ion with light allows the brain to perceive objects in the visual fields?

A

Na+

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
92
Q

What are the visual pigment molecules?

A

Rhodopsin (for rods) are present in the membrane folds

Rhodopsin = retinal (Vit A alternative) + Opsin (GPCR)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
93
Q

What does light do involving retinal (orange pigment)?

A

Converts II-cis-Retinal to all-trans-Retinal (activated form)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
94
Q

What does all-trans-Retinal do?

A

Activates transducin which down a molecular cascade leads to decreased cGMP, closing the cGMP channel

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
95
Q

What does closure of the cGMP channel in the eye do?

A

Reduces Na+ entry to the cells and causes hyperpolarisation

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
96
Q

What does closure of the cGMP channel in the eye do?

A

Reduces Na+ entry to the cells and causes hyperpolarisation

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
97
Q

What is the basic function of the Dark Current Channel?

A

Opens in the dark and closes in response to light
Opened by cGMP
Permeable to Na+
Keeps the photoreceptor Vm more +ve than most neurons
Gives a steady release of neurotransmitter

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
98
Q

What is visual acuity?

A

The ability to distinguish 2 nearby points

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
99
Q

What is visual acuity determined by?

A

Largely by photoreceptor spacing and refractive power

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
100
Q

Do rods or cones offer better acuity?

A

Cones

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
101
Q

Do rods or cones offer better sensitivity?

A

Rods

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
102
Q

What type of cones pick up blue light?

A

Short wave

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
103
Q

What type of cones pick up green light?

A

Middle wave

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
104
Q

What type of cones pick up red light?

A

Long wave

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
105
Q

What is the receptive field?

A

The part of the retina that needs to be stimulated to elicit APs from a ganglion cell

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
106
Q

What are the 2 halves of the retina called?

A

Nasal and Temporal hemiretinas

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
107
Q

Nerves from which hemiretina cross the optic chiasm?

A

Nasal

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
108
Q

What should be done in an asessment of a patient with ocular trauma?

A

Good history
Visual acuities
Examine eye(s)
Use fluoroscein drops to identify any areas of epithelial loss

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
109
Q

What should be done in an asessment of a patient with ocular trauma?

A

Good history
Visual acuities
Examine eye(s)
Use fluoroscein drops to identify any areas of epithelial loss

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
110
Q

What is a hyphaema?

A

A collection of blood in the anterior chamber of the eye

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
111
Q

What is sympathetic ophthalmia?

A

Where a penetrating injury is delivered to one eye but both eyes have an AI reaction to this and both eyes swell. May lead to bilateral blindness although this condition is rare!

112
Q

What are the usual intra-ocular foreign bodies found?

A

fast moving particles e.g. hammer and chisel injuries (usually sterile at entry)

113
Q

What investigation should always be done when suspicious of inta-ocular foreign bodies?

A

X-ray

114
Q

What would an alkaline chemical burn do to the eye?

A

Easy, rapid penetration
Cicatrising (scarring) changes to the conjunctiva and cornea
Penetrates the intra-ocular structures

115
Q

What would an acidic chemical burn do to the eye?

A

Coagulates proteins but shows little penetration

116
Q

What should be done immediately when a chemical burn presents?

A

Wash it out - reduces damage

117
Q

What eye movement defects may present with other systemic diseases?

A

Double vision (diplopia)

118
Q

What visual defects may present with other systemic diseases?

A

Decreased visual acuity

Field loss

119
Q

What diseases of the CNS may also present with eye symptoms?

A 
Tumours
Trauma
Demyelination
Inflammation/infection
Congenital abnormalities
120
Q

What diseases of the CNS may also present with eye symptoms?

A 
Tumours
Trauma
Demyelination
Inflammation/infection
Congenital abnormalities
121
Q

How would a CNVI palsy present?

A

Right lateral rectus palsy (responsible for adduction of eye)
If patient is asked to look to the right, the eye will more or less stay in the midline

122
Q

What are the potential causes of a CNVI palsy?

A

Microvascular
Raised ICP
Tumour
Congenital

123
Q

What other presentations may a CNVI palsy have when ICP is raised?

A

Papilloedema

May get caught on petrous tip of bone (another cause)

124
Q

How would a CNIV palsy present?

A

Right superior oblique (intorsion, depression in adduction and abduction)
Abnormal eye movements occur when looking straight ahead and when adducting
May expirience diplopia on looking down
Head tilted away from affected side to attempt to compensate for diplopa

125
Q

How may a patient with bilateral CNIV palsy present?

A

Chin depression and patient looking out of the tops of their visual fields (to avoid diplopa)

126
Q

What can cause bilateral CNIV palsy?

A

Blunt head trauma

127
Q

What the causes of CNIV palsy (unilateraly)?

A

Congenital decompensated
Mincrovascular
Tumour

128
Q

What the causes of CNIV palsy (unilateraly)?

A

Congenital decompensated
Mincrovascular
Tumour

129
Q

How would a CNIII palsy present?

A

Medial rectus, Inferior rectus, superior rectur , inferior oblique, sphincter pupillae and levator palpebra superioris
Occular position is down and out - lid is also down
Only eye movements which are unaffected are lateral and superiolateral ones

130
Q

What can cause a CNIII palsy?

A 
Microvascular
Tumour
Congenital
Aneurysm (esp. if painful!)
MS
131
Q

How would a inter-nuclear ophthamoplegia present?

A

Impaired horizontal eye movements with weak adduction of affected eyeand abduction nystagmus of contralateral eye

132
Q

What causes inter-nuclear ophthamoplegia?

A

a lesion in the medial longitudinal fasciculis (MLF) in the dorsomedial brainstem
MS
Vascular problems

133
Q

What is the order in the optic pathway?

A 
Optic nerve
Optic chiasm
Optic tracts
Optic radiations
Cortex
134
Q

What things can cause visual field defects?

A

Vascular disease
SOLs
Demyelination
Trauma

135
Q

What are the common pathologies of the optic nerve?

A

Ischaemia optic neuropathy
Optic neuritis
Tumours (rare)

136
Q

What symptoms would an optic neuritis present with?

A 
Progressive unilateral visual loss
Pain behind eye (esp.on movement)
Colour desaturation
Central scotoma - area of depressed vision corresponding with the fixation point
Gradual recovery over weeks-months
137
Q

What symptoms would an optic neuritis present with?

A 
Progressive unilateral visual loss
Pain behind eye (esp.on movement)
Colour desaturation
Central scotoma - area of depressed vision corresponding with the fixation point
Gradual recovery over weeks-months
138
Q

What visual field defect presents with a pathology of the optic nerve?

A

Either complete loss on one side
OR
Loss of vision of upper or lower segments

139
Q

What pathologies can affect the optic chiasm?

A

Pituitary tumours
Craniopharyngioma
Meningioma

140
Q

What visual field defect presents with a pathology affecting the optic chiasm?

A

Bi-temporal visual loss

141
Q

What pathologies can affect the optic tracts and radiations?

A

Tumours
Demyelination
Vascular anomalies

142
Q

What visual field defects may occur with pathologies affecting the optic tracts and radiations?

A

Either both lefts or both rights of the visual fields are involved
Quadrantanopia may also occur (always upper!)
Macula is not spared

143
Q

What pathologies affect the occipital cortex?

A

Vascular disease

Demyelination

144
Q

What visual field deformities arise from pathologies affecting the occipital cortex?

A

Either both lefts or both rights of the visual fields are involved
Macula IS spared

145
Q

What visual field deformities arise from pathologies affecting the occipital cortex?

A

Either both lefts or both rights of the visual fields are involved
Macula IS spared

146
Q

How is the cornea layered?

A

Lipid:Water:Lipid
Epithelium:stroma:epithelium

147
Q

What corneal layer are hydrophilic drugs limited by?

A

Epithelium

148
Q

What corneal layer are hydrophobic drugs limited by?

A

Stroma

149
Q

Chemical modifications may be needed to alter steroids characteristics; what makes a steroid more hydrophobic?

A

Alcohol or acetate

150
Q

Chemical modifications may be needed to alter steroids characteristics; what makes a steroid more hydrophilic?

A

Phosphate

151
Q

Describe the characteristics of prednisolone acetate.

A

Acetone dissolves in lipid
Hydrophobic
Good penetration in an uninflammed cornea

152
Q

What is prednisolone acetate used to treat?

A

Post-op for cataracts

153
Q

Describe the properties of prednisolone phosphate.

A

Hydrophilic

Poor penetration in an uninflammed cornea

154
Q

What is prednisolone phosphate used to treat?

A

Surface corneal disease

155
Q

Other than the corneal layers, what can be a barrier to drug penetration?

A

Tear film lipid layer

156
Q

What drug can disrupt the lipid layer of the tear film?

A

Benzalkonium

157
Q

What drugs can be used to lower IOP in glaucoma?

A

Bimatoprost (may cause pigmentations on eyes)

158
Q

How can drugs given topically for the eye gain systemic access?

A

Through the puncta leading to the nasopharynx

159
Q

How can drugs given topically for the eye gain systemic access?

A

Through the puncta leading to the nasopharynx

160
Q

In what way does chloramphenicol affect bacteria?

A

inhibits peptidyl transferase enzyme - stops bacterial protein being made

161
Q

What microorganisms is chloramphenicol affective against?

A

Strep. and Haemophilus (bacteriocidal)

Staph. (bacteriostatic)

162
Q

What are the side effects of chloramphenicol?

A

allergy
aplastic anaemia (rare!)
grey baby syndrome

163
Q

When should chloramphenicol NOT be used?

A

corneal ulcer treatment

164
Q

What antibiotics inhibit nucleic acid synthesis?

A

Quinolones (Ofloxacin) inhibit DNA gyrase - leads to cell death

165
Q

What antibiotics should be used for orbital and periorbital cellulitis?

A

systemic antibiotics e.g. flucloxacillin

166
Q

What antibiotics inhibit bacterial cell wall synthesis?

A

Penicillins and Cephalosporins

167
Q

What antivirals are used in the treatments of ophthalmological conditions?

A

Zovirax (aciclovir) - dendritic ulcers

168
Q

What are the main anti-inflammatory agents used in ophthalmology?

A

Steroids
Topical NSAIDs
Anti-histamines
Mast cell stabilisers

169
Q

What eye pathologies can topical steroids be used in?

A

Uveitis
After cataract surgery
Prevention of corneal graft rejection

170
Q

What is the most commonly used topical steroid in ophthalmology?

A

Prednisolone acetate

171
Q

What is the most commonly used topical steroid in ophthalmology?

A

Prednisolone acetate

172
Q

What are the local side effects of steroid use?

A

Cataract
Glaucoma
Exacerbation of viral infection

173
Q

What are the systemic side effects of steroid use?

A 
Gastric ulceration
Immunosppression
Osteoporosis
Weight gain
Diabetes
Neuropsychotic effects
174
Q

When are antihistamines and mast cell stabilisers used in eye disease?

A

Hayfever/allergic conjunctivitis

175
Q

When are NSAIDs used in eye disease?

A

For pain relief (post refractive laser)

176
Q

When are intravitreal drugs used?

A

Antibiotic administration in endophthalmitis
Intra-ocular steroids
Anti-VEGF

177
Q

When is local anaesthetic used in eye disease?

A

FB removal
Tonometry (IOP measurement)
Corneal scraping
Comfort from pain

178
Q

What can fluorescein be used for?

A

Showing corneal abrasion
Tonometry
Diagnosing lasolacrimal duct obstruction
Angiography

179
Q

What do mydriatics do?

A

(Tropicamide, cyclopentolate)

Cause pupil dilation by blocking parasympathetic supply to iris

180
Q

What are the side effects of mydriatics?

A

Blurring

Acute angle closure glaucoma

181
Q

What do sympathomimetics do?

A

(phenylephrine, atropine)

Act on the sympathetic system to dilate the pupil

182
Q

What is an ocular side effect of vigabatrin?

A

Field constriction

183
Q

What is an ocular side effect of steroids?

A

Cataract

184
Q

What is an ocular side effect of ethanbutal?

A

optic neuropathy

185
Q

What is an ocular side effect of chloroquine?

A

maculopathy

186
Q

What is an ocular side effect of chloroquine?

A

maculopathy

187
Q

What are the causes of sudden visual loss?

A 
Vessel occlusion
Mass haemorrhage
Retinal tear/detachment
ARMD - wet type
Close angle glaucoma
Optic neuritis
CVA
188
Q

What are the symptoms of central retinal artery occlusion (CRAO)?

A

sudden, painless visual loss
counting fingers or less vision wise
(CRA is an end artery)

189
Q

What signs are present in CRAO?

A

relative afferent pupil defect

pale, oedematous retina with thread-like retinal vessels

190
Q

What can cause CRAO?

A

Carotid artery disease

Emboli from heart (unusual)

191
Q

How is CRAO managed?

A

If less than 24h history then ocular massage can be performed to attempt to turn it into a branch occlusion
Establish source of embolus
Assess and manage risk factors

192
Q

What is Amaurosis fugax?

A

Transient CRAO

193
Q

What are the symptoms and signs of Amaurosis fugax?

A

Transient painless visual loss
Lasts 5 minutes with a full recovery
Usually nothing abnormal is seen on examination

194
Q

How is Amaurosis fugax managed?

A

Immediate referral to TIA clinic (risk v. high)

Aspirin

195
Q

How would a central retinal vein occlusion (CRVO) present?

A 
Sudden moderate-severe visual loss
Retinal haemorrhages
Dilated tortuous veins
Disc and macular swelling
Cotton wool spots on retina
196
Q

What systemic diseases can cause CRVO?

A

Atherosclerosis
Hypertension
Hyperviscosity

197
Q

What ocular disease can cause CRVO?

A

Increased IOP - venous stasis

198
Q

How would a CRVO be treated?

A

Treatment of systemic or ocular causes
Monitor fundus for neovascularisation
anti-VEGFFs (vascular epithelial growth factor)

199
Q

How would a CRVO be treated?

A

Treatment of systemic or ocular causes
Monitor fundus for neovascularisation
anti-VEGFFs (vascular epithelial growth factor)

200
Q

What happens in ischaemic optic neuropathy?

A

posterior cilliary arteries (PCA) become occluded, resulting in infarction of the optic nerve head

201
Q

What are the 2 types of ischaemic optic neuropathy?

A

Arteritic - GCA (50%)

Non-arteritic - atherosclerosis (50%)

202
Q

How does ischaemic optic neuropathy present?

A

Sudden, profound visual loss with a swollen disc
GCA = irreversible blindness
Pale, swollen disc

203
Q

What symptoms are associated with GCA?

A 
Headache
Jaw claudication
scalp tenderness
amaurosis fugax
malaise
v.high inflammatory markers
204
Q

How is GCA treated?

A

Prevention of visual loss in other eye

  • prompt recognition
  • immediate high dose systemic steroid
  • refer urgently!!!
205
Q

What is vitreous haemorrhage associated with?

A

Retinal ischaemia and new vessel formation

206
Q

What is retinal haemorrhage associated with?

A

Retinal tear

207
Q

What are the signs and symptoms associated with vitreous haemorrhage?

A

LOV
Floaters
Loss of red reflex

208
Q

How is vitreous haemorrhage treated?

A

Cause is identified

Vitrectomy for non-resolving cases

209
Q

What are the symtoms of retinal detachment?

A

painless LOV
Sudden onset of flashes/floaters
tear may be visible on ophthalmoscopy

210
Q

How are retinal tears usually managed?

A

Surgery

211
Q

What are the symtoms of retinal detachment?

A

painless LOV
Sudden onset of flashes/floaters
tear may be visible on ophthalmoscopy
may have relative afferent pupillary defect (RAPD)

212
Q

How are retinal tears usually managed?

A

Surgery

213
Q

What are the 2 types of age related macular degeneration (ARMD) and how do they differ?

A

Dry - gradual LOV

Wet - sudden LOV

214
Q

What happens in wet ARMD?

A

New blood vessels grow under the retina - leakage causes build up of fluid/blood and eventual scarring

215
Q

What are the signs and symptoms of wet ARMD?

A

rapid central visual loss
visual distortion
haemorrage/exudate on fundus

216
Q

How is wet ARMD treated?

A

anti-VEGF injected into vitreous cavity

217
Q

What are the causes of gradual visual loss?

A 
CARDIGAN
C = cataract
A = ARMD dry
R = refractive error
D = diabetic retinopathy
I = inherited disease (retinitis pigmentosa)
G = glaucome
A = access (to eye clinic) N = non-urgant
218
Q

What can cause cataract?

A 
Age
Congenital - intrauterine infection
trauma
metabolic (diabetes)
drugs (steroids)
219
Q

What are the different types of cataract?

A

nuclear
posterior subcapsular
polychomatic
congenital

220
Q

How is cataract managed?

A

Surgical removal with intra-ocular lens implant

221
Q

What are the signs and symptoms of dry ARMD?

A

central vision gradually becomes ‘missing’
Drunsen - build-up of waste products below RPE
RPE changes - atrophy/hyperplasia

222
Q

What are the signs and symptoms of dry ARMD?

A

central vision gradually becomes ‘missing’
Drunsen - build-up of waste products below RPE
RPE changes - atrophy/hyperplasia

223
Q

How is dry ARMD treated?

A

No cure - supportive with low vision aids e.g. magnifying glass

224
Q

How is dry ARMD treated?

A

No cure - supportive with low vision aids e.g. magnifying glass

225
Q

What is myopia?

A

Short sightedness

226
Q

What is hypermetropia?

A

Long sightedness

227
Q

What is astigmatism?

A

An irregular corneal curvature (rugby ball shaped)

228
Q

What is presbyopia?

A

Loss of lens accomodation with aging

229
Q

What happens in open angle glaucoma?

A

IOP rises gradually
Retinal nerve fibres are damaged
Visual field contracts

230
Q

What symptoms and signs appear with open angle glaucoma?

A

often non symptoms are described
raised IOP
cupped disc
Visual field defect

231
Q

How is open angle glaucoma treated?

A

Pressure lowering eye drops
occasionally surgery
regular monitoring

232
Q

What is papilloedema?

A

Swollen optic discs secondary to raised ICP

233
Q

In patients with bilateral papilloedema what should be suspected until proven otherwise?

A

Raised ICP due to a SOL

234
Q

What are the processes behind papilloedema?

A

Subarachnoid space arund the optic nerve is continuous with the subarachnoid space surrounding the brain
When ICP rises, this is transmitted to the space around the optic nerve
This causes interruption of axoplasmic flow and venous congestion

235
Q

What 3 components add together to create the ICP?

A

Brain (80%)
Blood (10%)
CSF (10%)

236
Q

What happens if ICP increases?

A

Brain is squeezed through foramen magnum, the brainstem is compressed, causes breathing issues and possibly death.

237
Q

What happens if ICP increases?

A

Brain is squeezed through foramen magnum, the brainstem is compressed, causes breathing issues and possibly death.

238
Q

What are the functions of CSF?

A 
Maintains a stable extracellular environment for brain
Buoyancy
Waste removal
Mechanical protection
Nutrition
239
Q

What is the choroid plexus?

A

A network of capillaries which filter blood to form CSF

240
Q

What causes ICP to increase?

A

Obstruction to CSF circulation
Overproduction of CSF
Inadequate absorption

241
Q

What are the signs of chronic disc swelling?

A

Disc becomes atrophic and pale

Loss of visual function and blindness

242
Q

What can cause anterior blepharitis?

A

Seborrhoeic (squamous) scles on the lashes
Staph infection involving the lash follicle
Lid margin is redder than the deeper part of the lid

243
Q

What can cause posterior blepharitis?

A

Meibomian gland dysfunction
Redness in deeper part of the lid
Lid margin is often quite normal looking

244
Q

What symptoms and signs does blepharitis show?

A

Similar to conjunctivitis
Gritty eyes
Foreign body sensation
mild discharge

245
Q

How does a seborrhoeic blepharitis present?

A

Red lid margin
Lots of scales
Dundruff

246
Q

How does a staphylococcal blepharitis present?

A

Red lid margin
Lashes distorted, loss of lashes, ingrowing lashes
Styes - ulcers of lid margin
Corneal staining and marginal ulcers

247
Q

How does a staphylococcal blepharitis present?

A

Red lid margin
Lashes distorted, loss of lashes, ingrowing lashes
Styes - ulcers of lid margin
Corneal staining and marginal ulcers

248
Q

How does Meibomian gland disease present?

A 
Lid margin skin and lashes are unaffected
MG openings are pouting and swollen
Dried secretion at gland openings
Meibomian cysts (chalazia)
Associated with acne rosacea (50% cases)
249
Q

How is blepharitis treated?

A

Lid hygiene - daily bathing/warm compresses
Supplementary tear drops
Oral doxycycline for 2-3 months
V. difficult to completely eradicate

250
Q

What can cause a follicular conjunctivitis?

A

Viral (adeno, HS, HZ)
Chlamydial
Drug-induced e.g. propine and trusopt
Secondary to molluscum contagiosum

251
Q

What can cause a follicular conjunctivitis?

A

Viral (adeno, HS, HZ)
Chlamydial
Drug-induced e.g. propine and trusopt
Secondary to molluscum contagiosum

252
Q

What are the signs and symptoms of corneal ulcers?

A 
Needle-like pain
Photophobia
Profuse lacrimation
Vision may be decreased
Red eye
Abnormal red reflex
Corneal opacity
Hypopyon
Stains with fluorescein
253
Q

What are the treatments for corneal ulcers?

A

Identify the cause
Ofloxacin hourly if bacterial in cause
Aciclovir 5x/day if viral
Steroids for inflammation

254
Q

What are the causes of anterior uveitis?

A

AI - Reiters, UC, ankylosing spondylitis, sarcoidosis
Malignancy - Leukemia
Infective - TB, syphilis, HS, HZ
Others - idiopathic, traumatic, secondary to other eye disease

255
Q

What are the symptoms of anterior uveitis?

A

Pain
Vision possibly decreased
Photophobia
Red eye

256
Q

What are the signs of anterior uveitis?

A

Ciliary injection
Cells and flare in the anterior chamber
keratic precipitates
hypopyon

257
Q

How is anterior uveitis managed?

A

Topical steroids
Mydriatics - cyclopentolate
Investigations for systemic associations if recurrent or chronic

258
Q

What is episcleritis?

A

relatively common - associated with gout

Recurrent - nodules may occur

259
Q

How is episcleritis treated?

A

Self-limiting

Lubricants/topical NSAIDs/mild steroids

260
Q

How is episcleritis treated?

A

Self-limiting

Lubricants/topical NSAIDs/mild steroids

261
Q

What is scleritis?

A

Association with serious systemic vasculitides
Very painful
Injection of the deep vascular plexus
Commonly associated with uveitis

262
Q

How is scleritis treated?

A

Oral NSAIDs
Oral steroids
Steroid sparing agents

263
Q

How does acute closed angle glaucoma?

A 
a rare condition
IOP is acutely raised due to the drainageangle being closed
Most likely to occur in a hypermetropic elderly person with thick glasses
Sever pain and nausea
Circumcorneal injection
Cornea is cloudy
Pupil-mid dilated
Eye is stony hard
264
Q

What is the pathogenesis of diabetic retinopathy?

A

Chronic hyperglycaemia
glycosylation of protein/basement
loss of pericytes
microaneurysm

265
Q

What signs are present in non-proliferative retinopathy?

A

Micro-aneurysms
Hard exidate
Cotton wool patches
Intra-retinal microvascular abnormalities

266
Q

What is new vessel growth on the iris know as?

A

Rubeosis iridis

267
Q

What causes diabetic patients to lose their vision?

A

Retinal oedema affecting the fovea
Vitreous haemorrhage
scarring/fractional retinal detachment

268
Q

Hos is diabetic retinopathy managed?

A

Optimise management of diabetes
Laser therapy
Surgery

269
Q

What signs appear on the retina of an individual with hypertension?

A

Attenuated blood vessels
Cotton wool spots and hard exudates
Retinal haemorrhage and optic disc oedema

270
Q

Is CRAO painful?

A

Yes

271
Q

Is CRVO painful?

A

No

272
Q

How can thyroid disease affect the eye?

A 
Proptosis
Lid retraction/oedema/lag/pigmentation
Restrictive myopathy
Chemosis, injection, exposure, glaucoma
Chorodial folds, optic nerve swelling
273
Q

How is thyroid eye disease managed?

A

Control of thyroid dysfunction
Lubricants
Surgical decompression

274
Q

How can SLE affect the eyes?

A

Ocular inflammtion

275
Q

How can RA affect the eyes?

A

Dry eyes
Scleritis
Corneal melt

276
Q

How can erythema multiforme affect the eyes?

A

Occulsion of lacrimal glands
Corneal ulcers
Symblepharon (adhesion of conjunctiva to eyeball)

x 2nd Year Medicine (10 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions