Ophthalmology notes Flashcards
1
Q
Name 4 ocular adnexa
A
Eyelids
Lacrimal glands
Naso-lacrimal duct
Lacrimal sac
2
Q
What is emmetropia
A
Normal vision
3
Q
What is the medical term for long sightedness
A
Hypermetropia
4
Q
What is presbyopia and what causes it
A
Long-sightedness due to loss of elasticity of lens over time
5
Q
Name a gram positive and gram negative coccus species
A
Gram + -> Staph/Strep
Gram - -> Neisseria
6
Q
What is keratitis
A
Inflammation of the cornea
7
Q
What is orbital cellulitis
A
Inflammation behind orbital septum
8
Q
What is the most common cause of bacterial conjunctivitis
A
Staph Aureus
9
Q
What investigation and treatment is done for suspected bacterial conjunctivitis
A
Swab -> topical chloramphenicol
10
Q
When should chloramphenicol not be given
A
History of aplastic anaemia or allergy
11
Q
What are 3 common causes of viral conjunctivitis
A
Herpes zoster
Adenovirus
Herpes Simplex
12
Q
What kind of conjunctivitis shows sub tarsal scarring and follicle development
A
Chlamydial Conjunctivitis
13
Q
What kind of keratitis can present with hypopyon
A
Bacterial
14
Q
What kind of keratitis can present with a dendritic ulcer
A
Herpetic keratitis
15
Q
Which steroid is given as treatment for herpetic keratitis
A
DONT GIVE STEROIDS
can cause corneal melt
16
Q
What kind of keratitis presents with bilateral sub-epithelial infiltrates
A
Adenoviral Keratitis
17
Q
Name 2 common causes of fungal keratitis
A
Pseudomonas
Acanthamoeba
18
Q
Who tends to get fungal keratitis
A
Contact lens wearers
19
Q
Which ENT pathology can lead to orbital cellulitis
A
Sinusitis
20
Q
Which scan must be done in suspected orbital cellulitis
A
CT scan
21
Q
What is CMV chorioretinitis
A
CMV infection of choroid and retina
Seen in HIV patients
22
Q
Investigation for Bacterial Keratitis
A
Corneal scrape
23
Q
Investigation for endophthalmitis
A
Aqueous/Vitreous culture
24
Q
Mechanism of action of Chloramphenicol
A
Inhibits protein synthesis
25
Mechanism of action of Penicillin & Cephalosporin
Inhibit cell wall synthesis
26
Mechanism of action of Quinolones
Inhibits nucleic acid synthesis
27
What specifically does Chloramphenicol inhibit
Peptidyl Transferase
28
Name some side effects of Chloramphenicol
Irreversible aplastic anaemia
| Grey-baby syndrome
29
Mechanism of action of Aciclovir
Base Analogue (mimics guanine)
30
Treatment for Chlamydial conjunctivitis
Topical oxytetracycline
31
Treatment for genital chlamydia
Oral Azithromycin
32
Treatment for bacterial keratitis
Gentamicin + Cefuroxime
33
Which ventricles contain the choroid plexus
3rd and 4th
34
Compare the chemical makeup of CSF to water with regards to NaCl, K+, Glucose & proteins
CSF has higher concentrations of NaCl
| Water has higher concentrations of K+, glucose & protein
35
How does CSF return to venous blood
Via Arachnoid granulations in the Superior Sagittal Sinus
36
Where does CSF predominantly circulate
Subarachnoid space
| Between pia and dura mater
37
What is pseudotumour cerebri
Idiopathic inter-cranial hypertension
38
Where does aqueous humour drain
To the scleral venous sinus via the trabecular meshwork and the canal of Schlemm
39
Which cells are responsible for lateral connections in the retina
Amacrine cells
| Horizontal cells
40
What is the resting membrane potential in photoreceptor cells and why
-20mV due to a constant influx of Na+ in the dark
41
What is the dark current
cGMP gated Na+ channel open in the dark but closed in light
42
Which chemical conversion modulates the dark current
The conversion of 11-cis-retinal to all-trans-retinal
43
What are the three main immune cells in the eye
Mast cells
Macrophages
Neutrophils
44
What is the only part of the eye with lymphatic drainage
Conjunctiva
45
Are there Langerhans cells in the cornea or sclera
Langerhans cells are in the peripheral cornea
46
What is ACAID (Anterior Chamber Associated Immune Deviation)
Peripheral tolerance to ocular antigens
47
What can be described as bilateral granulomatous uveitis
Sympathetic Ophthalmia
48
Which eye is the exciting eye in Sympathetic Ophthalmia
The injured eye
| the fellow eye is the sympathising eye
49
What is a Dalen-Fuchs nodule
An epithelial cell cluster in the retinal layers
50
Give an example of a Type 1 hypersensitivity of the eye
Acute allergic conjunctivitis
51
Give an example of a Type 2 hypersensitivity of the eye
Ocular cicatricial pemphigoid
52
Give an example of a Type 3 hypersensitivity of the eye
Autoimmune corneal melting
53
Give an example of a Type 4 hypersensitivity of the eye
Corneal graft rejection
54
What is the sensory supply to the Dura Mater
CN V
55
Which meningeal layer are the dural venous sinuses in
Dura Mater
56
Which meningeal layer are the arachnoid granulations in
Arachnoid mater
57
Where does the subarachnoid space stop with regards to the spinal cord
S2
58
Where is the 3rd ventricle
In midline with the diencephalon
59
Where is the 4th ventricle
Between the cerebellum and pons
60
What will the eye look like in a patient with 3rd nerve palsy
```
Ptosis (loss of eyelid muscle)
Dilated pupil (loss of sphincter of the pupil)
Eye down and out (LR & SO functioning)
```
61
When will a patient with 4th nerve palsy get diplopia
When looking down
| eye can't move inferomedially
62
What should you always do for suspected Intra-Ocular-Foreign-Body
X-ray orbits
63
Is an alkali or acid burn worse and why
Alkali is worse because it easily and rapidly penetrates
| Acid coagulases protein so has little penetration
64
What does intracameral mean
Into the anterior chamber of the eye
65
What is the structure of the cornea in terms of lipid and water
lipid: water: lipid
epithelium: stroma: endothelium
66
What can be added to drugs to make them more hydrophobic
Alcohol or Acetate
67
What can be added to drugs to make them more hydrophilic
Phosphate
68
What kind of disease would Prednisolone Phosphate be used for and why
```
Corneal disease
(phosphate makes it more hydrophilic so the drug does not penetrate and remains on cornea)
```
69
Name a preservative that is used and how it enhances corneal penetration
Benzalkonium
| disrupts lipid layer of tear film
70
When is the intra-vitreal mode of administration used
To administer antibiotics in endophthalmitis
| To administer anti-VEGF
71
What is the mechanism of action of anaesthetics used in tonometry/ corneal scrape
Block Na+ channels
| impede nerve conduction
72
How do mydriatic drugs work
Cause pupil dilation by blocking parasympathetic supply to the iris
73
What visual field side effect can Vigabatrin have
Constriction of the visual field
74
What visual field side effect can Ethambutol have
Optic neuropathy
75
What visual field side effect can Chloroquine have
Maculopathy
76
What is the pathogenesis of diabetic retinopathy
Glycosylation of basement membranes
| leads to loss of basement pericytes
77
What are the 3 classifications of new vessel growth in the eye
Growth on disc (NVD)
Growth in the periphery (NVE)
Growth on iris (Rubeosis iridis)
78
The central retinal artery supplies the inner 2/3rd's of the retina, what supplies the outer 1/3rd
Choroid
79
Management of Central Retinal Artery Occlusion
If in 24 hours - Ocular massage to try and convert it to BRAO
80
Management of Central Retinal Vein Occlusion
Anti-VEGF
81
Which arteries, that supply the optic nerve head, become occluded in Ischaemic Optic Neuropathy
Posterior Ciliary Arteries
82
Ischaemic Optic Neuropathy can be arteritic or non-arteritic - Name a cause of each type
Arteritic - Giant Cell Arteritis
| Non- Arteritic - Atherosclerosis
83
What could a loss of the red reflex suggest
Retinoblastoma
Vitreous haemorrhage
Retinal detachment
Cataract
84
What do flashes and floaters suggest
Retinal Detachment
85
What do haloes around lights suggest
Acute Angle Closure Glaucoma
86
Treatment of dry ARMD
Low vision aids (magnifiers)
87
What kind of visual field defect does open-angle glaucoma cause
Arcuate field defect
88
What should you assume is causing bilateral papilloedema until proven otherwise
Space-occupying lesion in the brain
89
What is the Monroe-Kellie hypothesis
States that if one component of inter-cranial pressure changes, the others must also change to compensate
90
What are the two causes of anterior blepharitis
Seborrhoeic (on eyelashes)
| Staphylococcal (on hair follicle)
91
What is usually the cause of posterior blepharitis
Meibomian gland dysfunction
92
What derm condition is posterior blepharitis associated with
Acne Rosacea
93
Which derm condition can follicular conjunctivitis be secondary to
Molluscum Contagisoum
94
How can you differentiate between infective and autoimmune corneal ulcers
Infective ulcers tend to be central
| Autoimmune ulcers tend to be peripheral
95
Treatment for bacterial corneal ulcers
Ofloxacin hourly
96
Which MSK pathologies are Episcleritis and Scleritis associated with
Episcleritis - Gout
| Scleritis - Rheumatoid Arthritis
97
Which test is done for Scleritis
Phenylephrine test
98
What kind of vision puts you at a higher risk of retinal detachment
Myopia
| short-sighted
99
What kind of vision puts you at a higher risk of Acute Angle Closure Glaucoma
Hypermetropia
| long-sighted
100
What disease are Brushfield spots seen in
Down Syndrome
101
What disease are Kayser Fleischer rings seen in
Wilson's disease
102
What disease are blue sclera seen in
Osteogenesis Imperfecta
103
CRVO can present with a relative afferent pupillary defect true or false
True
104
What is the normal range of intraocular pressure
10-21mmHg
105
Name a risk factor for ARMD
Smoking
106
If a patient presents complaining that straight lines are appearing wavy/curvy, what should you think of
ARMD
107
Which endocrine disease can cause vitreous haemorrhages
Diabetes
108
Flashes and Floaters suggest what pathology
Retinal detachment
109
When can contact lenses be worn in a patient with conjunctivitis
Should not be worn
110
What is the next course of action in a patient with ARMD and neovascularization
Fluorescein angiography
111
What is another name for a Marcus-Gunn pupil and what are the two possible causes
RAPD
| Damage to optic nerve/ retina
112
What is a retinal cause of a relative afferent pupillary defect
Retinal detachment
113
What is an optic nerve cause of a relative afferent pupillary defect
Optic neuritis
114
Which biochemical abnormality can predispose to cataract formation
Hypocalcaemia
115
60 year old asthmatic presents with symptoms consistent with open-angle glaucoma. Tonometry confirms this with an intraocular pressure of 29mmHg. What is the management
Latanoprost (prostaglandin analogue)
| b-blocker contraindicated due to asthma
116
A fractured zygoma tends to rotate in which direction and what can this disrupt
Medially
| can disrupt suspensory eye ligament
117
Which tendon is attached to the superior tarsus
Levator Palpebrae Superioris
118
What is another name for Muller's muscle
Superior tarsal muscle
119
What is the innervation of the lacrimal gland
CN VII (parasympathetic)
120
Where do all rectus muscles originate
Common Tendinous ring
121
Which nerve is responsible for conduction of afferent action potentials from the cornea in the blink reflex
CN V1 (long ciliary branch)
122
Which three things are being tested in the accommodation reflex and which structures are involved
Bilateral pupillary constriction (Spinchter pupillae)
Bilateral midline convergence (Medial rectus)
Bilateral lens relaxation (Ciliary muscle constriction)
123
Bilateral conjunctivitis in young adults can indicate what
Chlamydial Conjunctivitis
124
What kind of eye disease can result in sub tarsal scarring
Chlamydial Conjunctivitis
125
What is the most common cause of endophthalmitis and what is the treatment
Staph Epidermidis
| Ceftazidime/ Vancomycin/ Intra-vitreal Amikacin
126
What do quinolones inhibit
DNA gyrase
| thus inhibiting nucleic acid synthesis
127
What enzyme does chloramphenicol inhibit
Peptidyl transferase
128
Where on the cornea are Langerhan's cells NOT found
Absent from central 1/3rd
129
Which two eye structures are known as the tough collagen coat and have no lymphatics or vasculature
Cornea + Sclera
130
Describe an Epidural Haematoma
Arterial bleed between skull and dura mater
131
Describe a Subdural Haematoma
Venous bleed between dura mater and arachnoid mater
132
What are the lateral and medial apertures of the 4th ventricle also known as and what space do they open to
Subarachnoid space
Lateral -> Foramen of Luschka
Medial -> Foramen of Magendie
133
What is the foramen of Monro
Connects 3rd and lateral ventricles
134
Define visual acuity
The ability to distinguish between 2 points
135
What colour of light do short medium and long wavelength cones allow us to see
Short -> Blue
Medium -> Green
Long -> Red
