Ophthalmology Flashcards
What is the most common cause of unilateral proptosis?
A ) Cavernous haemangioma of the orbit
B ) Intracranial space-occupying lesion
C ) Lymphoma
D ) Optic nerve sheath meningioma
E ) Orbital cellulitis
F ) Thyroid eye disease
Answer: Thyroid eye disease
Unilateral proptosis is most commonly due to thyroid eye disease. This is the commonest cause for unilateral or bilateral axial proptosis in adults (more common in females). It is further confirmed by the fact that intraocular pressure rises on up gaze due to the involvement of inferior rectus muscle.
A ) Central retinal artery occlusion
B ) Central retinal vein occlusion
C ) Glaucoma
D ) Macular degeneration
E ) Non-proliferative retinopathy
F ) Proliferative retinopathy
Answer: Central retinal artery occlusion
A ) Central retinal artery occlusion
B ) Central retinal vein occlusion
C ) Glaucoma
D ) Macular degeneration
E ) Non-proliferative retinopathy
F ) Proliferative retinopathy
Answer: Proliferative retinopathy
Explanation: Diabetic retinopathy represents microvascular end-organ damage as a result of diabetes. Vascular endothelial growth factor (VEGF) is secreted by the ischemic retina. VEGF leads to increased vascular permeability resulting in retinal swelling/edema and angiogenesis or new blood vessel formation.
Causes of a small pupil include which of the following?
A ) Carbon monoxide poisoning
B ) Ethylene glycol poisoning
C ) Holmes-Adie pupil
D ) Pontine haemorrhage
E ) Third nerve palsy
Answer: Pontine haemorrhage
A ) Central retinal vein occlusion
B ) Diabetic retinopathy
C ) Hypertensive retinopathy
D ) Raised intracranial pressure
E ) Retinal detachment
Answer: Hypertensive retinopathy
A ) Central facial nerve palsy
B ) Fourth nerve palsy
C ) Internuclear ophthalmoplegia (INO)
D ) Peripheral facial nerve palsy
E ) Sixth nerve palsy
F ) Third nerve palsy
= C) Internuclear ophthalmoplegia (INO)
Internuclear ophthalmoplegia is a disconnection syndrome characterised by impaired horizontal gaze. It occurs as a result of interruption to the medial longitudinal fasciculus (MLF), commonly due to multiple sclerosis or haemorrhage. Affected individuals have slowed or limited adduction in the eye ipsilateral to the lesion, with associated abducting nystagmus in the contralateral eye. In the diagram below, the right eye is not able to fully adduct (look toward the left side) while the left eye can fully adduct.
Which ocular pathology is NOT associated with type II diabetes?
A ) Anterior uveitis
B ) Cataracts
C ) Diabetic retinopathy
D ) Extraocular muscle palsy
E ) Glaucoma.
= A) Anterior uveitis
Explanation: Diabetes is associated with retinopathy, cataract (a rare ‘snowflake’ cataract in youth and a greater frequency and earlier onset of age related cataract), glaucoma (but the association of chronic open angle glaucoma is disputed), and extraocular muscle palsy due to microvascular disease of the third, fourth, or sixth cranial nerves
Answer: Maxilla bone
Answer: 10-21mmHg
Glaucoma is a group of eye diseases that cause intraocular pressure (IOP) to rise, in some cases as high as 70mmHg. In primary open-angle glaucoma (POAG), the most common form, there is a reduced outflow of aqueous humour through the trabecular meshwork.
Answer: Zygomatic bone
Which of the following is a cause of sudden visual loss?
A ) Cataracts
B ) Chronic glaucoma
C ) Optic atrophy
D ) Optic neuritis
E ) Tobacco amblyopia
Answer: Optic neuritis
What is the most common cause of orbital cellulitis?
A ) Adenovirus
B ) Chlamydia trachomatis
C ) Pseudomonas aeruginosa
D ) Staphylococcus and streptococcus species
E ) Varicella zoster virus
Answer: Staphylococcus and streptococcus species
Answer: Non-proliferative diabetic retinopathy
In non-proliferative diabetic retinopathy, chronic hyperglycaemia causes damage to retinal capillaries, weakening capillary walls. These microaneurysms can rupture in a dot-like appearance referred to as “dot-and-blot” haemorrhages. Fluid from the leaky vessels can recede, leaving behind lipid byproducts which appear as “hard exudates”.
Answer: Episcleritis
Answer: Separation of the iris (Iridodialysis)
You are performing fundoscopy on a patient with hypertensive retinopathy when you are asked to describe your
findings. What does “copper and silver wiring” refer to?
A ) Abnormal colouring of the arterioles
B ) An enlarged retinal arteriole that crosses a vein and can press down and cause swelling distal to the crossing
C ) Capillary occlusion ischaemia and degeneration of the vascular smooth muscle
D ) Degeneration of retinal blood vessels to the point where they leak plasma and bleed onto the retina
E ) Small areas of yellow-white discolouration on the retina
Answer: Abnormal colouring of the arterioles
Answer: Iritis (anterior uveitis)
How does acute iritis present?
Presentation of acute iritis
- Painful inflammation of the iris
- Uncommon in children – can be acute, chronic or relapsing
- May be associated with other conditions, such as rheumatoid arthritis, Behçet’s disease, malignancy, trauma to eye, infection.
How does viral conjunctivitis present?
Presentation of viral conjunctivitis
- Common condition (more common than bacterial form)
- Presents with pink conjunctiva and dilated blood vessels
- Not usually associated with pain, photophobia or visual disturbance
- Discharge unusual, although the eye may water excessively
- Often associated with a viral URTI
Which of the following ocular emergencies is also life threatening?
A ) Acute glaucoma
B ) Acute iritis
C ) Corneal ulcer
D ) Leukocoria (white reflex)
E ) Lid/globe lacerations
Answer: Leukocoria (white reflex)
A ) Infective endocarditis
B ) Myeloma
C ) Syphilis
D ) Systemic lupus erythematosus
E ) Tay-Sachs disease
Answer: Infective endocarditis
The presence of white-centred haemorrhages (Roth spots) should prompt the consideration of possible infective endocarditis. This patient’s diagnosis was confirmed with echocardiography and blood cultures.
Answer: Optic canal
Answer: Corneal foreign body
Answer: Retinal detachment
Answer: Subconjunctival haemorrhage
Answer: Acute angle-closure glaucoma
Answer: Infraorbital groove
Which of the following ophthalmic conditions can occur in HLA-B27 associated diseases (e.g. ankylosing spondylitis, inflammatory bowel disease, and reactive arthritis)?
A ) Acute anterior uveitis
B ) Conjunctivitis
C ) Herpes keratitis
D ) Open angle glaucoma
E ) Posterior vitreous detachment
Answer: Acute anterior uveitis
Answer: Frontal bone
Answer: Marginal keratitis
You have been referred a case of primary open-angle glaucoma. Which of the following findings would be important in diagnosing the case?
A ) Corneal ulcer
B ) Injected conjunctiva
C ) Narrow drainage angle between the cornea and iris
D ) Optic disc cupping
E ) Refractive error
Answer: Optic disc cupping
In opthalmological terms, backward displacement of the globe is known as __________.
A ) Enophthalmos
B ) Exophthalmos
C ) Midbrain pupil
D ) Preseptal cellulitis
E ) Proptosis
Answer: Enophthalmos
Explanation: Enophthalmos is backward displacement of the globe. This may be seen following an orbital fracture when orbital contents are displaced into an adjacent sinus. It is also said to occur in Horner’s syndrome but this is really a pseudo-enophthalmos due to narrowing of the palpebral fissure.
Answer: Herpes simplex keratitis
The hallmark of HSV keratitis is the presence of multiple small branching epithelial dendrites on the surface of the cornea, although often times it first presents as a coarse, punctuate epithelial keratitis, which may be mistaken for a viral keratitis.
Answer: Retinal detachment
Which of the following is a triangular, fleshy wing of conjunctiva that encroaches on the cornea?
A ) Chalazion
B ) Entropion
C ) Hyphaema
D ) Pterygium
E ) Strabismus
Answer: Pterygium
Answer: Herpes simplex keratitis
48 hours following cataract surgery, a patient complains of ocular pain and visual loss. On examination, their eye appears red with ciliary injection, corneal oedema, and an absent red reflex. The first suspicion must be:
A ) Acute conjunctivitis
B ) Anterior uveitis
C ) Bacterial endophthalmitis
D ) Corneal ulcer
E ) Secondary glaucoma
Answer: Bacterial endophthalmitis
Answer: Central retinal vein occlusion
Causes of mydriasis include which of the following?
A ) Argyll Robertson pupil
B ) Horner’s syndrome
C ) Old age
D ) Opiates
E ) Third nerve palsy
Answer: Third nerve palsy
Answer: Branch retinal artery occlusion
Answer: Amaurosis fugax
Answer: Cotton wool spots
Cotton wool spots are white spots on the retinal surface caused by microinfarction. They are mainly associated with hypertension and diabetes, but can be seen with HIV, lupus, thrombocytopaenia, hypercoagulable states, connective tissue disorders, and other conditions.
Answer: sympathetic : dilation
A patient blinks both eyes when the right cornea is touched and does not blink at all when the left cornea is touched. Where is the problem?
A ) Left facial nerve
B ) Left ophthalmic nerve (branch of trigeminal nerve)
C ) Right facial nerve
D ) Right ophthalmic nerve (branch of trigeminal nerve)
E ) Both facial and ophthalmic nerve
Answer: Left ophthalmic nerve (branch of trigeminal nerve)
Answer: Central retinal artery occlusion
Answer: Inferior orbital fissure
Answer: Marginal keratitis
With aging, the elasticity of the lens and the strength of the ciliary muscle decrease, resulting in the loss of accommodation. In this condition, light from nearby objects falls behind the retina, causing blurred vision.
What is the name of this condition?
A ) Emmetropia
B ) Hyperopia
C ) Myopia
D ) Neurotropia
E ) Presbyopia
Answer: Presbyopia
What structure produces aqueous humor?
A ) Ciliary processes
B ) Cornea
C ) Iris
D ) Lense
E ) Retina
= A) Ciliary processes
Answer: Pupillary constriction and an increase in the refractive power of the lens
Answer: parasympathetic : constriction
Posterior cerebral artery (PCA) infarction causes which of the following visual lesions?
A ) Bitemporal heteronymous hemianopsia
B ) Contralateral homonymous hemianopsia
C ) Contralateral homonymous hemianopsia with macular sparing
D ) Contralateral upper homonymous quadrantanopsia
E ) Ipsilateral blindness
= C ) Contralateral homonymous hemianopsia with macular sparing
Angiogenesis contributes to the cause of what visual defect in diabetes?
A ) Cataracts
B ) Glaucoma
C ) Hyperopia
D ) Myopia
E ) Rubeosis iridis
= E ) Rubeosis iridis
Which of the following most accurately describes the pupillary light reflex?
A ) Its afferent nerve is the optic (CN II) and its efferent nerve is the oculomotor (CN III)
B ) Its afferent nerve is the optic (CN III) and its efferent nerve is the oculomotor (CN II)
C ) Its afferent nerve is the trigeminal (CN V) and its efferent nerve is the facial (VII)
D ) Its efferent nerve is the optic (CN II) and its afferent nerve is the oculomotor (CN III)
E ) Its efferent nerve is the optic (CN III) and its afferent nerve is the oculomotor (CN II)
= A) Its afferent nerve is the optic (CN II) and its efferent nerve is the oculomotor (CN III)
Answer: Central retinal vein occlusion
Lesion of which part of the visual pathway is shown by the following visual defect?
= Answer: Meyer’s loop