Opthalmology Flashcards
Define blepharitis
Inflammation of the eyelid margins
Features of blepharitis
- bilateral
- grittiness and discomfort, particularly around the eyelid margins
- eyes may be sticky in the morning
- eyelid margins may be red. 5. Swollen eyelids may be seen in staphylococcal blepharitis
- styes and chalazions
- secondary conjunctivitis
Diagnosis of blepharitis
Clinical diagnosis
Define conjuctivitis
Inflammation of the conjunctiva due to allergic or immunological reactions, infection (viral, bacterial or parasitic), mechanical irritation, neoplasia, or contact with toxic substances
Symptoms of infective conjunctivitis
- Sore – grittiness, burning sensation
- red eyes
- sticky discharge
Symptoms of allergic conjunctivitis
- Bilateral symptoms conjunctival erythema, conjunctival swelling (chemosis)
- Itch is prominent
- the eyelids may also be swollen
- Discharge
Ix for infective conjunctivitis
Infective conjunctivitis:
- Swabs taken if referral not required
What is corneal abrasion?
Corneal abrasions are defects in the epithelial surface of the cornea
Symptoms for corneal abrasion
- Eye pain
- Tearing
- Photophobia
- Blurred vision
- Ciliary flush - A ring of red or violet around the cornea.
Ix for corneal abrasion
Fluorescein staining
Define keratitis
Inflammation of the cornea.
Microbial kearatitis - Potentially sight threatening
Features of keratitis
- red eye: pain and erythema
- photophobia
- foreign body, gritty sensation
- hypopyon ( yellowish exudate in lower part of anterior chamber of eye)
Ix for keratitis
Diagnostic: slit-lamp
Referral for keratitis
- assessing contact lens wearers who present with a painful red eye is difficult
- an accurate diagnosis can only usually be made with a slit-lamp, meaning same-day referral to an eye specialist is usually required to rule out microbial keratitis
What is pterygium?
A pterygium is a raised, triangular or wedge-shaped, benign growth of conjunctiva tissue.
Symptoms of pterygium
Mild irritation (redness, dryness, foreign body sensation),, tearing
What is Chalazion?
Meibomian cyst (Chalazion)
Symptoms of Chalazion
Firm painless lump in the eyelid
Localized eyelid swelling that has developed slowly over several weeks.
Investigation of Chalazion
Invert the eyelid a discrete immobile granuloma nodule should be seen.
What is orbital cellulitis?
Result of an infection affecting the fat and muscles posterior to the orbital septum.
MEDICAL EMERGENCY
Features of orbital cellulitis
- Redness and swelling around the eye
- Severe ocular pain
- Visual disturbance
- Proptosis
- Ophthalmoplegia/pain with eye movements
- Eyelid oedema and ptosis
- Drowsiness +/- Nausea/vomiting in meningeal involvement (RARE)
Ix for orbital cellulitis
- FBC – 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 is Dacryoadenitis?
inflammation of the lacrimal gland and may be unilateral or bilateral.
What is strabismus?
Squint (strabismus) is characterised by misalignment of the visual axes.
Ix for strabismus
- Detection of a squint may be made by the corneal light reflection test - holding a light source 30cm from the child’s face to see if the light reflects symmetrically on the pupils
- The cover test is used to identify the nature of the squint
Define cataract
lens of the eye gradually opacifies i.e. becomes cloudy.
Features of cataract
- Reduced vision
- Faded colour vision: making it more difficult to distinguish different colours
- Glare: lights appear brighter than usual
- Halos around lights
- Signs: defect in red reflex
Ix for cataract
- Ophthalmoscopy: done after pupil dilation
- Findings: normal fundus and optic nerve - Slit-lamp examination
- Findings: visible cataract
In age related macular degenration (ARMD), which part of the eye is affected?
Degeneration of the central retina (macula) is the key feature with changes usually bilateral
Features of ARMD
Patients typically present with a subacute onset of visual loss with:
- a reduction in visual acuity, particularly for near field objects
- difficulties in dark adaptation with an overall deterioration in vision at night
- fluctuations in visual disturbance which may vary significantly from day to day
- they may also suffer from photopsia, (a perception of flickering or flashing lights), and glare around objects
Signs of ARMD
- distortion of line perception may be noted on Amsler grid testing
- fundoscopy = drusen, yellow areas of pigment deposition in the macular area, which may become confluent in late disease to form a macular scar.
- in wet ARMD well demarcated red patches may be seen which represent intra-retinal or sub-retinal fluid leakage or haemorrhage.
Ix for ARMD
- slit-lamp microscopy is the initial investigation of choice, to identify any pigmentary, exudative or haemorrhagic changes affecting the retina which may identify the presence of ARMD.
- Next: colour fundus photography to provide a baseline against which changes can be identified over time.
- fluorescein angiography is utilised if neovascular ARMD is suspected, as this can guide intervention with anti-VEGF therapy.
- Next: indocyanine green angiography to visualise any changes in the choroidal circulation.
- ocular coherence tomography is used to visualise the retina in three dimensions, because it can reveal areas of disease which aren’t visible using microscopy alone.
What is ectropion?
out-turning of the eyelids
What is entropion?
in-turning of the eyelids
What is diabetic retinopathy?
Hyperglycaemia is thought to cause increased retinal blood flow and abnormal metabolism in the retinal vessel walls.
-This precipitates damage to endothelial cells and pericytes
Features of diabetic retinopathy
- microaneurysms
- blot haemorrhages
- hard exudates
- cotton wool spots, venous beading/looping and intraretinal microvascular abnormalities (IRMA) less severe than in severe NPDR
Features of retinal detachment
- Retinal detachment: dense shadow 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
What is retinal vascular occlusion due to?
Due to thromboembolism (from atherosclerosis) or arteritis (e.g. temporal arteritis)
Features of retinal vascular occlusion
- Sudden painless loss of vision
- features include afferent pupillary defect, ‘cherry red’ spot on a pale retina
- Fundoscopy: Retinal haemorrhages
What is retinoblastoma?
most common ocular malignancy found in children
Features of retinoblastoma
- absence of red-reflex, replaced by a white pupil (leukocoria) - the most common presenting symptom
- strabismus
- visual problems
What is raised intracranial pressure?
As the brain and ventricles are enclosed by a rigid skull, they have a limited ability to accommodate additional volume.
- Additional volume (e.g. haematoma, tumour, excessive CSF) will therefore lead to a rise in intracranial pressure (ICP).
Features of raised ICP
- headache
- vomiting
- reduced levels of consciousness
- papilloedema
- Cushing’s triad
o widening pulse pressure
o bradycardia
o irregular breathing
Ix for raised ICP
- Neuroimaging – CT/MRI
2. Invasive ICP monitoring
Features of Optic Neuritis
- unilateral decrease in visual acuity over hours or days
- poor discrimination of colours, ‘red desaturation’
- pain worse on eye movement
- relative afferent pupillary defect
- central scotoma
What is thyroid eye disease associated with?
Graves’ disease.
Features of thyroid eye disease
- the patient may be eu-, hypo- or hyperthyroid at the time of presentation
- exophthalmos
- conjunctival oedema
- optic disc swelling
- ophthalmoplegia
- inability to close the eyelids may lead to sore, dry eyes. If severe and untreated patients can be at risk of exposure keratopathy
Features of horner’s syndrome
- miosis (small pupil)
- ptosis
- enophthalmos* (sunken eye)
- anhidrosis (loss of sweating one side)
Features of 3rd Nerve palsy
- eye is deviated ‘down and out’
- ptosis
- pupil may be dilated (sometimes called a ‘surgical’ third nerve palsy)
What is Holmes-Adie Pupil ?
Holmes-Adie pupil is a benign condition most commonly seen in women. It is one of the differentials of a dilated pupil
Features of Holmes-Adie Pupil
- unilateral in 80% of cases
- dilated pupil
- once the pupil has constricted it remains small for an abnormally long time
- slowly reactive to accommodation but very poorly (if at all) to light
- association of Holmes-Adie pupil with absent ankle/knee reflexes
What is glaucoma?
Glaucomas are optic neuropathies associated with raised intraocular pressure (IOP)
Features of primary open angle glaucoma
POAG may present insidiously and for this reason is often detected during routine optometry appointments.
- peripheral visual field loss - nasal scotomas progressing to ‘tunnel vision’
- decreased visual acuity
- optic disc cupping
Difference between Primary Open – Angle Glaucoma & Acute Angle-Closure Glaucoma
Open-angle = chronic condition with few symptoms,
Closed-angle = an acute condition with sudden symptoms.
Ix for Primary Open – Angle Glaucoma
- Fundoscopy: optic disc cupping, optic disc pallor, bayonetting of vessels, disc haemorrhages
- Slit lamp examination with pupil dilation
- Applanation to measure IOP
What is Acute Angle-Closure Glaucoma?
In acute angle-closure glaucoma (AACG) there is a rise in IOP secondary to an impairment of aqueous outflow. Factors predisposing to AACG include:
- hypermetropia (long-sightedness)
- pupillary dilatation
- lens growth associated with age
Features of Acute Angle-Closure Glaucoma
- 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
