Ophthalmology 1 Flashcards
What proportion of patients with rheumatoid arthritis have eye problems?
25%
What eye problems are associated with rheumatoid arthritis?
Ocular manifestations
- keratoconjunctivitis sicca (most common)
- episcleritis (erythema)
- scleritis (erythema and pain)
- corneal ulceration
- keratitis
Iatrogenic
- steroid-induced cataracts
- chloroquine retinopathy
What’s the most common ocular manifestation of rheumatoid arthritis?
keratoconjunctivitis
What’s the diagnosis? Rheumatoid arthritis, erythema and pain
scleritis
What’s the diagnosis? Rheumatoid arthritis and erythema
episcleritis
What does AACG stand for?
Acute angle closure glaucoma
What are risk factors in developing AACG?
- hypermetropia (long-sightedness)
- pupillary dilatation
- lens growth associated with age
What’s the word for long-sightedness?
Hypermetropia
What are the features of AACG?
- severe pain: may be ocular or headache
- decreased visual acuity
- symptoms worse with mydriasis (e.g. watching TV in a dark room)
- hard, red eye
- haloes around lights
- semi-dilated non-reacting pupil
- corneal oedema results in dull or hazy cornea
- systemic upset may be seen, such as nausea and vomiting and even abdominal pain
What’s the management for AACG?
- urgent referral to an ophthalmologist
- management options include reducing aqueous secretions with acetazolamide and inducing pupillary constriction with topical pilocarpine
What type of drug is acetazolomide?
Carbonic anhydrase inhibitor
How does pilocarpine work?
It is a cholinergic agonist. It acts on a subtype of muscarinic receptor (M3) found on the iris sphincter muscle, causing the muscle to contract -resulting in pupil constriction (miosis). Pilocarpine also acts on the ciliary muscle and causes it to contract. When the ciliary muscle contracts, it opens the trabecular meshwork through increased tension on the scleral spur. This action facilitates the rate that aqueous humor leaves the eye to decrease intraocular pressure.
How does herpes simplex keratitis normally present?
With a dendritic corneal ulcer
What is acantholysis?
The loss of intercellular connections, such as desmosomes, resulting in loss of cohesion between cells.
What are the symptoms of herpes simplex keratitis?
- red, painful eye
- photophobia
- epiphora
- visual acuity may be decreased
- fluorescein staining may show an epithelial ulcer
What does a dendritic corneal ulcer look like?
- the boarders are slightly raised, greyish and stain with rose bengal (fluorescein) as they consist of infected cells that have undergone acantholysis.
What can be left once a dendritic scar has healed?
A dendritic shaped scar called a ghost dentrite can remain in the superficial stroma.
How do you manage herpes simplex keratitis?
- immediate referral to an ophthalmologist
- topical aciclovir
What are the features of anterior uveitis?
- acute onset
- ocular discomfort & pain (may increase with use)
- pupil may be irregular and small
- photophobia (often intense)
- blurred vision
- red eyes
- lacrimation
- ciliary flush
- hypopyon
- visual acuity initially normal → impaired
What is hypopyon?
Describes pus and inflammatory cells in the anterior chamber, often resulting in a visible fluid level.
Which conditions are associated with anterior uveitis?
- ankylosing spondylitis
- reactive arthritis
- ulcerative colitis, Crohn’s disease
- Behcet’s disease
What’s the management for anterior uveitis?
- urgent review by ophthalmology
- cycloplegics (dilates the pupil which helps to relieve pain and photophobia) e.g. Atropine, cyclopentolate
- steroid eye drops
Cyclopentolate is a muscarinic antagonist. It is commonly used as an eye drop during pediatric eye examinations to dilate the eye (mydriatic) and prevent the eye from focusing/accommodating (cycloplegic).
What are cycloplegics and give examples?
Drugs that dilate the pupil which helps to relieve pain and photophobia associated with anterior uveitis
e.g. Atropine, cyclopentolate
What’s the term for excessive watering of the eye?
Epiphora
What are the most common causes of a sudden painless loss of vision?
- ischaemic optic neuropathy (e.g. temporal arteritis or atherosclerosis)
- occlusion of central retinal vein
- occlusion of central retinal artery
- vitreous haemorrhage
- retinal detachment
What are altitudinal visual field defects?
This term describes a visual field defect in which either the upper or lower half of the visual field is selectively affected.
What can cause ischaemic optic neuropathy?
- may be due to arteritis (e.g. temporal arteritis) or atherosclerosis (e.g. hypertensive, diabetic older patient)
- due to occlusion of the short posterior ciliary arteries, causing damage to the optic nerve
What vision loss can occur in ischaemic optic neuropathy?
Altitudinal field defects
What’s the word for a keyhole eye?
coloboma
What steps do you take when examining the eye?
- WIPER
- ask about if they use glasses and if they are long/short sighted
- ask if they have had any eye drops (to dilate the pupil) and turn the light to dim
- ask them to focus on a distant point
- use the same hand/eye as they eye you’re viewing
- hold the brow
- warn them that you will be close to them
- approach from 15 degrees
What causes central retinal vein occlusion?
- glaucoma
- polycythaemia
- hypertension
- incidence increases with age
What do floaters or flashing lights suggest?
- vitreous detachment
- vitreous haemorrhage
- retinal detachment
What do vertical visual defects suggest?
Neuro-ophthalmic abnormality at or posterior to the optic chiasm.
Jaw claudication and headache. Diagnosis?
Giant cell arteritis
What is the most common cause of acute onset floaters in an older person?
Posterior vitreous detachment
In posterior vitreous detachment what is indicative that the retina is being pulled?
Floaters (posterior vitreous detachment) and flashes
How would acuity and visual fields be affected in posterior vitreous detachment?
The visual acuity is characteristically normal, and there should be no loss of visual field.
How would you manage a patient with posterior vitreous detachment?
Patients with an acute posterior vitreous detachment should have an urgent (same day) ophthalmic assessment, so that any retinal breaks or detachment can be identified and treated at an early stage.
The patient may require a further visit one to two months later to exclude subsequent development of a retinal hole.
What’s the name for the corneal scleral junction?
Limbus
What are the features of a vitreous haemorrhage?
History
- sudden onset floaters or blobs in vision
- visual acuity reduced if bleed severe
- flashing lights indicated retinal traction and are dangerous
Examination
- acuity decreased depending on size of bleed
- projection of light is usually accurate unless haemorrhage is extremely dense
- Ophthalmoscopy: shows the red reflex to be reduced; there may be clots of blood that move with the vitreous.
How does the bleeding occur in vitreous haemorrhage?
- spontaneous rupture of vessels
- avulsion (tearing off) of vessels during retinal traction
- bleeding from abnormal new vessels (diabetes)
When is retinal detachment during a vitreous haemorrhage more likely?
If the person is short sighted.
How would you manage a patient with a vitreous haemorrhage?
- The patient should be referred to an ophthalmologist to exclude a retinal detachment (B scan; type of ultrasound).
- Ultrasound examination of the eye may be useful, particularly if the haemorrhage precludes a view of the retina.
- Underlying causes such as diabetes must also be excluded.
- If a vitreous haemorrhage fails to clear spontaneously the patient may benefit from having the vitreous removed (vitrectomy).
What are the features of posterior vitreous detachment?
- Flashes of light (photopsia) - in the peripheral field of vision
- Floaters, often on the temporal side of the central vision
What are the features of a retinal detachment?
History
- Dense shadow that starts peripherally progresses towards the central vision
- A veil or curtain over the field of vision
- Straight lines appear curved
- Central visual loss
- features of vitreous detachment, which may precede retinal detachment, include flashes of light or floaters
Examination
- Visual acuity is normal if the macula is still attached, but the acuity is reduced to counting fingers or hand movements if the macula is detached.
- Field loss (not complete in the early stages) is dependent on the size and location of the detachment.
- Direct ophthalmoscopy will not detect the abnormality if the detachment is small; detached retinal folds may be seen in larger detachments.
What are the risk factors for retinal detachment?
- if the retina is thin (in the shortsighted patient)
- damaged (by trauma)
- if the ocular dynamics have been disturbed (by a previous cataract operation).
- Traction from a contracting membrane after vitreous haemorrhage in a patient with diabetes.
What’s the term for shortsightedness?
Myopia
What’s the name for surgery to remove a section of the eyelid?
blepharoplasty
What’s the term for the eyelids turning in and the lashes rubbing on the cornea?
Entropian
How would you manage a patient with retinal detachment?
- The patient should be referred urgently.
- Only small retinal holes with no associated fluid under the retina can be treated with a laser, which causes an inflammatory reaction that seals the hole.
- True detachments usually require an operation to seal any holes, reduce vitreous traction, and if necessary drain fluid from beneath the neuroretina.
- A vitrectomy may be required, which is carried out using fine microsurgical cutting instruments inserted into the eye with fibreoptic illumination. This may be combined with the use of special intraocular gases (for example, sulphur hexafluoride) or silicone oil to keep the retina flat. If gas is used the patient may have to posture face down for several weeks after surgery in cases of retinal detachment, and must not travel by air (the intraocular gas expands at altitude) until most of the gas in the eye has been absorbed.
- Cryotherapy is used to treat the retinal hole causing the retinal detachment. Cryotherapy is applied to the sclera overlying the retinal tear. It causes scarring which seals the retinal hole.
- Belting.
What causes central retinal artery occlusion? What are the features?
Due to thromboembolism (from atherosclerosis) or arteritis (e.g. temporal arteritis).
Features include:
- sudden onset visual disturbance (‘greyout’ or curtain descending)
- afferent pupillary defect
- ‘cherry red’ spot on a pale retina (this is caused by oedema and seeing the choroid vessels underneath)
What’s the term for a temporary loss of vision like a curtain coming down?
Amaurosis fugax
What can cause arterial occlusion?
- atherosclerosis
- emboli
- thrombosis
What causes cherry red spots
The retina infarcts and becomes odematous and masks the blood of the choroid. The macula is thinner so you can still see it at this point.
What’s the vascular supply to the retina?
Retinal artery and branches: inner 2/3 of neuroretina
Choroid: outer 1/3
What are the layers of the sclera?
- episclera
- stroma
- lamina fusca
- endothelium
What’s it called when VZV is in the eye?
Herpes zoster ophthalmicus
What are the features of herpes zoster ophthalmicus?
- vesicular rash around the eye, which may or may not involve the actual eye itself
- Hutchinson’s sign: rash on the tip or side of the nose. Indicates nasociliary involvement and is a strong risk factor for ocular involvement
How do you manage herpes zoster ophthalmicus?
- oral antiviral treatment for 7-10 days, ideally started within 72 hours. Topical antiviral treatment is not given in HZO
- oral corticosteroids may reduce the duration of pain but do not reduce the incidence of post-herpetic neuralgia
- ocular involvement requires urgent ophthalmology review
What are the complications of herpes zoster ophthalmicus?
- ocular: conjunctivitis, keratitis, episcleritis, anterior uveitis
- ptosis
- post-herpetic neuralgia
What’s the most common cause of blindness in adults aged 35-65?
Diabetic retinopathy
What’s the mechanism of diabetic retinopathy?
- hyperglycaemia is thought to increase the retinal blood flow and abnormal metabolism in the retinal vessel walls
- this causes damage to endothelial cells and pericytes
- endothelial dysfucntion leads to increased vascular permeability which causes the characteristic exudates
- pericyte dysfunction perdisposes to the formation of microaneurysms
- neovascularization is thought to be caused by the production of growth factors in response to retinal ischaemia
What are the characteristic features of the different stages of diabetic retinopathy?
Traditional classification
Background retinopathy
- microaneurysms (dots)
- blot haemorrhages (<=3)
- hard exudates
Pre-proliferative retinopathy
- cotton wool spots (soft exudates; ischaemic nerve fibres)
- > 3 blot haemorrhages
- venous beading/looping
- deep/dark cluster haemorrhages
- more common in Type I DM, treat with laser photocoagulation
New classification
Mild NPDR
- 1 or more microaneurysm
Moderate NPDR
- microaneurysms
- blot haemorrhages
- hard exudates
- cotton wool spots, venous beading/looping and intraretinal microvascular abnormalities (IRMA) less severe than in severe NPDR
Severe NPDR
- blot haemorrhages and microaneurysms in 4 quadrants
- venous beading in at least 2 quadrants
- IRMA in at least 1 quadrant
What does NPDR stand for?
Non-proliferative diabetic retinopathy
What’s the difference between proliferative retinopathy and maculopathy?
Proliferative retinopathy
- retinal neovascularisation - may lead to vitrous haemorrhage
- fibrous tissue forming anterior to retinal disc
- more common in Type I DM, 50% blind in 5 years
Maculopathy
- based on location rather than severity, anything is potentially serious
- hard exudates and other ‘background’ changes on macula
- check visual acuity
- more common in Type II DM
What is blepharitis?
Inflammation of the eyelid margins.
What causes blepharitis?
- meibomian gland dysfunction (common, posterior blepharitis)
- seborrhoeic dermatitis/staphylococcal infection (less common, anterior blepharitis).
What are the layers of the tear film and which glands produce the fluid?
- an oil (lipid) layer (meibomian glands)
- a water (aqueous) layer (lacrimal glands)
- a mucin layer (goblet cells)
Which condition is more common in patients with rosacea?
Blepharitis
What are the features of blepharitis?
- symptoms are usually bilateral
- grittiness and discomfort, particularly around the eyelid margins
- eyes may be sticky in the morning
- eyelid margins may be red. Swollen eyelids may be seen in staphylococcal blepharitis
- styes and chalazions are more common in patients with blepharitis
- secondary conjunctivitis may occur
What’s the medical name for a stye?
Hordeolum
What are hordeola?
Acute, infected, and painful lesions at the rim of the eyelid. Infection of the glands of the eyelids.
What are chalazia?
Subacute or chronic, noninfected, and generally less painful lesions on the conjunctival side of the eyelid.
Caused by blockage of meibomian glands
What’s the management for blepheritis?
- softening of the lid margin using hot compresses twice a day
- mechanical removal of the debris from lid margins - cotton wool buds dipped in a mixture of cooled boiled water and baby shampoo is often used*
- artificial tears may be given for symptom relief in people with dry eyes or an abnormal tear film
*an alternative is sodium bicarbonate, a teaspoonful in a cup of cooled water that has recently been boiled
A 71-year-old man presents with severe pain around his right eye and vomiting. On examination the right eye is red and decreased visual acuity is noted. Which one of the following options is the most appropriate initial management?
Acute glaucoma? - admit immediately
What is glaucoma?
A group of diseases characterised by optic neuropathy
A 68-year-old man with a history of type 2 diabetes mellitus presents with worsening eye sight. Mydriatic drops are applied and fundoscopy reveals pre-proliferative diabetic retinopathy. A referral to ophthalmology is made. Later in the evening whilst driving home he develops pain in his left eye associated with decreased visual acuity. What is the most likely diagnosis?
Mydriatic drops are a known precipitant of acute angle closure glaucoma. This scenario is more common in exams than clinical practice.
A 35-year-old man presents with visual problems. He has had very poor vision in the dark for a long time but is now worried as he is developing ‘tunnel vision’. He states his grandfather had a similar problem and was registered blind in his 50’s. What is the most likely diagnosis?
Retinitis pigmentosa - night blindness + tunnel vision
Which part of the retina is affected in retinitis pigmentosa and what does it result in?
Peripheral retina, tunnel vision
What are the features of retinitis pigmentosa?
- night blindness is often the initial sign
- tunnel vision
- Fundoscopy:
1. black bone spicule-shaped pigmentation in the peripheral retina
2. pale atrophic optic disc
3. attenuation of arterioles
Which conditions is retinitis pigmentosa associated with?
- Refsum disease: cerebellar ataxia, peripheral neuropathy, deafness, ichthyosis
- Usher syndrome
- abetalipoproteinemia
- Lawrence-Moon-Biedl syndrome
- Kearns-Sayre syndrome
- Alport’s syndrome
How do you differentiate between orbital cellulitis and preorbital cellulitis?
presence of the following in orbital cellulitis:
- reduced visual acuity
- proptosis
- pain with eye movements
Which disease is the most common cause of nephrotic syndrome which would cause bilateral periorbital oedema?
Minimal change disease
What is orbital cellulitis?
The result of an infection affecting the fat and muscles posterior to the orbital septum, within the orbit but not involving the globe.
What usually causes orbital cellulitis?
spreading upper respiratory tract infection from the sinuses
What is periorbital (preseptal) cellulitis?
Periorbital (preseptal) cellulitis is a less serious superficial infection anterior to the orbital septum, resulting from a superficial tissue injury (chalazion, insect bite etc…). Periorbital cellulitis can progress to orbital cellulitis.
What are the risk factors for orbital cellulitis?
- Childhood
- Previous sinus infection
- Lack of Haemophilus influenzae type b (Hib) vaccination
- Recent eyelid infection/ insect bite on eyelid (Peri-orbital cellulitis)
- Ear or facial infection
What are the presenting features of orbital cellulitis?
- Redness and swelling around the eye
- Severe ocular pain
- Visual disturbance
- Proptosis
- Ophthalmoplegia
- Eyelid oedema and ptosis
- Drowsiness +/- Nausea/vomiting in meningeal involvement (Rare)
What investigations would you do for orbital cellulitis?
- Full blood count – WBC elevated, raised inflammatory markers.
- Clinical examination involving complete ophthalmological assessment – Decreased vision, afferent pupillary defect, proptosis, dysmotility, oedema, erythema.
- CT with contrast – Inflammation of the orbital tissues deep to the septum, sinusitis.
- Blood culture and microbiological swab to determine the organism. Most common bacterial causes – Streptococcus, Staphylococcus aureus, Haemophilus influenzae B.
What are the most common bacterial causes of orbital cellulitis?
- Streptococcus
- Staphylococcus aureus
- Haemophilus influenzae B
What’s the term for eyelids turning out?
Ectropion
What can happen if an entropion is left untreated?
Can develop a corneal ulcer
How do you manage an entropion?
Surgery but eye lubricants and tape (to pull they eyelid outwards) can be helpful whilst awaiting surgery.
Is a chalazion painful?
No
What are the different types of stye? How do you treat them?
- external (hordeolum externum): infection (usually staphylococcal) of the glands of Zeis (sebum producing) or glands of Moll (sweat glands).
- internal (hordeolum internum): infection of the Meibomian glands. May leave a residual chalazion (Meibomian cyst)
- management includes hot compresses and analgesia. CKS only recommend topical antibiotics if there is an associated conjunctivitis
What’s a pinguecula?
A yellowish, slightly raised thickening of the conjunctiva on the white part of the eye (sclera), close to the edge of the cornea.
A 70-year-old female presents to her general practitioner with a vesicular rash affecting the right-side of her face and tip of her nose. She is diagnosed with herpes zoster ophthalmicus (HZO).
Which of the following is the most likely complication in this lady?
Anterior uveitis - given that she has vesicles on her nose, it is likely she has ocular involvement therefore she is at risk of anterior uveitis.
What’s are the features of an Argyll-Robertson pupil?
small, irregular pupils
no response to light but there is a response to accommodate.
What can cause an Argyll-Robertson pupil?
diabetes mellitus
syphilis
What’s an Adie pupil?
- Tonically dilated pupil
- Slowly reactive to light with more definite accommodation response
- Caused by damage to the parasympathetic innervation of the eye due to viral or bacterial infection.
- Commonly seen in females, accompanied by absent knee or ankle jerks.
What’s a Marcus-Gunn pupil?
- Relative afferent pupillary defect, seen during the swinging light examination of pupil response
- The pupils constrict less and therefore appear to dilate when a light is swung from unaffected to the affected eye.
- Most commonly caused by damage to the optic nerve or severe retinal disease.
What’s Horner’s syndrome?
- miosis (pupillary constriction)
- ptosis (droopy eyelid)
- apparent enophthalmos (inset eyeball)
- with or without anhidrosis (decreased sweating) occurring on one side
- Caused by damage to the sympathetic trunk on the same side as the symptoms, due to trauma, compression, infection
What’s a Hutchinson’s pupil?
- Unilaterally dilated pupil which is unresponsive to light.
- A result of compression of the oculomotor nerve of the same side, by an intracranial mass (e.g. tumour, haematoma)
