Ophth! Flashcards
What is conjunctivitis?
Inflammation of the conjunctiva.
May be bacterial, viral or allergic
Presentation of conjunctivitis
-red, bloodshot eye
-itchy or gritty sensation
-discharge
Presentation of bacterial conjunctivitis vs viral conjunctivitis
Bacterial:
-purulent discharge, eyes stuck together in morning
-usually starts in one eye
-highly contagious
Viral:
-clear discharge
-viral symptoms- dry cough, sore throat and blocked nose
-may be tender pre-auricular lymph nodes
-contagious
Name causes of acute painful red eye
-acute angle- closure glaucoma
-anterior uveitis
-scleritis
-corneal abrasions or ulceration
-keratitis
-foreign body
-traumatic or chemical injury
Name causes of acute painless red eye
-conjunctivitis
-episcleritis
-subconjunctival haemorrhage
What causes neonatal conjunctivitis?
Gonococcal infection
-can cause serious complications e.g., permanent vision loss
Management for conjunctivitis?
-usually resolves within 1-2 weeks without needing treatment
-hygiene measures to reduce spreading
-cleaning the eyes with cooled boiled water and cotton wool to help with discharge
-Chloramphenicol or fusidic acid eye drops are options for bacterial conjunctivitis if necessary
What is allergic conjunctivitis and what can help with symptoms?
-caused by contact with allergens
-causes swelling of the conjunctival sac and eyelid with itchy and a watery discharge
-antihistamines can help with symptoms
-topical mast-cell stabilisers can help with chronic seasonal symptoms-they work by preventing mast cells from releasing histamine and require several weeks of use before they show benefit
Describe blepharitis
-inflammation of the eyelid margins
-it causes a gritty, itchy, dry sensation in the eyes
-it can be associated with dysfunction of the Meibomian glands, which are responsible for secreting meibum (oil) onto the surface of the eye
-it can lead to styes and chalazions
Describe styes
-a style causes a tender red lump along the eyelid that may contain pus
Hordeolum externum is an infection of the glands of Zeis or glands Moll. <- name for external eye stye
Hordeolum internum is infection of the Meibomian glands. They are deeper, tend to be more painful and may point inwards towards the eyeball underneath the eyelid.
-Styes are treated with hot compresses and analgesia.
Topical antibiotics (e.g., chloramphenicol) may be considered if it is associated with conjunctivitis or if symptoms are persistent.
What is Chalazion?
-A chalazion occurs when a Meibomian gland becomes blocked and swells.
-AKA Meibomian cyst
-Presents with a swelling in the eyelid that is typically not tender
-Treatment is with warm compress and gentle massage towards the eyelashes (to encourage drainage). Rarely, surgical drainage may be required.
What is Entropion?
Entropion refers to when the eyelid turns inwards with the lashes pressed against the eye.
This causes pain and can result in corneal damage and ulceration.
Initial management is by taping the eyelid down to prevent it from turning inwards.
Definitive management is surgical.
Same day referral to ophthalmology as there is a risk to sight!
Eye drops to prevent eyes from drying out.
What is Ectropion?
Ectropion refers to when the eyelid turns outwards, exposing the inner aspect.
-usually affects bottom lid
-can result in exposure keratopathy
-regular lubricating drops
What is Trichiasis?
-Trichiasis refers to inward growth of the eyelashes.
-It results in pain and can cause corneal damage and ulceration.
-Management involves removing the affected eyelashes.
-Recurrent cases may require electrolysis, cryotherapy or laser treatment to prevent them from regrowing.
What is periorbital cellulitis?
-AKA preseptal cellulitis
-an eyelid and skin infection in front of the orbital septum.
-presents with swollen, red, hot skin around the eyelid and eye.
-treatment is with systemic antibiotics (oral or IV)
-it can develop into orbital cellulitis which is a sight and life-threatening emergency
-a CT scan can be used to distinguish between periorbital and orbital cellulitis
What is orbital cellulits?
Orbital cellulitis is an infection around the eyeball involving the tissues behind the orbital septum.
Symptoms= pain with eye movement, reduced eye movements, vision changes, abnormal pupil reactions, and proptosis
Emergency admission under ophthalmology and intravenous antibiotics. Surgical drainage may be needed if an abscess forms.
What are the most common causes of a sudden painless loss of vision?
-ischaemic/vascular -> thrombosis, embolism, temporal arteritis, occlusion of central retinal vein and artery
-vitreous haemorrhage
-retinal detachment
-retinal migraine
What are drusen?
Extracellular deposits that from beneath the retina
What is the most common cause of blindness in adults aged 35-65 years-old?
Diabetic retinopathy
What is an acute angle closure galucoma?
When the iris bulges forward and seals off the trabecular meshwork from the anterior chamber, preventing aqueous humour from draining and leading to a continual increase in intraocular pressure. This pressure builds in the posterior chamber, pushing the iris forward and exacerbating the angle closure.
It is an ophthalmological emergency requiring rapid treatment to prevent permanent vision loss.
Risk factors for acute angle-closure glaucoma
-increasing age
-FH
-female
-Chinese and East Asian ethnic origin
-shallow anterior chamber
Presentation of acute angle-closure glaucoma
-severely painful red eye
-blurred vision
-halos around lights
-associated headache, nausea and vomiting
Signs on examination in acute angle-closure glaucoma
-red eye
-hazy cornea
-decreased visual acuity
-mid-dilated pupil
-fixed-size pupil
-hard eyeball on gentle palpation
Management of acute angle-closure glaucoma
Initial management:
-lying the patient on their back without a pillow
-Pilocarpine eye drops
-Acetazolamide
-analgesia and an antiemetic, if required
What is usually required for definitive treatment?
Laser iridotomy- makes a hole in the iris which allows the aqueous humour to directly from the posterior chamber to the anterior chamber. This relieves the pressure pushing the iris forward against the cornea and opens the pathway for the aqueous humour to drain.
What is a glaucoma?
-Glaucoma refers to the optic nerve damage caused by a rise in intraocular pressure. Raised intraocular pressure is caused by a blockage in aqueous trying to escape the eye.
There are 2 types of glaucoma:
-open-angle glaucoma
-acute angle-closure glaucoma
What is retinal detachment?
Retinal detachment involves the neurosensory layer of the retina (containing photoreceptors and nerves) separating from the retinal pigment epithelium (the base layer attached to the choroid). This is usually due to a retinal tear, allowing vitreous fluid to get under the neurosensory retina and fill the space between the layers.
The neurosensory retina relies on the blood vessels of the choroid for its blood supply. Therefore, retinal detachment can disrupt the blood supply and cause permanent damage to the photoreceptors, making it sight-threatening.
What are the risk factors for retinal detachment?
-lattice degeneration (thinning of the retina)
-posterior vitreous detachment
-trauma
-diabetic retinopathy
-retinal malignancy
-family history
Presentation of retinal detachment
-peripheral vision loss (often sudden and described as a shadow coming across the vision)
-blurred or distorted vision
-flashes and floaters
Management of retinal tears
-laser therapy
-cryotherapy
Management of retinal detachment
-aims to reattach the retina and reduce any traction or pressure that may cause it to detach again
-options are vitrectomy, scleral buckle or pneumatic retinopexy
Patients presenting with … should have a detailed assessment to detect retinal tears and retinal detachment
painless flashes and floaters
What does myopia mean?
Short-sightedness
What is epiphoria?
Excess tears / watery eyes
What are drusen and what are they associated with?
Drusen are associated with dry macular degeneration (the most common type of macular degeneration); these are small yellowish deposits of lipids that accumulate under the retina.
What is the definitive treatment for acute angle-closed glaucoma?
Laser peripheral iridotomy is the definitive treatment for acute angle-closure glaucoma
-it involves creating a small hole in the peripheral iris, which allows aqueous humour to flow freely and relieves the blockage causing the angle closure
What does scotoma mean?
Scotoma is the medical term for a visual field abnormality, or a blind spot
What are cataracts?
Cataracts describe a progressively opaque eye lens, which reduces the light entering the eye and visual acuity.
-cloudy lens!
What is the role of the lens? What is it held in place by?
To focus light on the retina.
It is held in place by suspensory ligaments attached to the ciliary body.
The lens has no blood supply and is nourished by the aqueous humour.
What is the role of the ciliary body?
The ciliary body contracts and relaxes to change the shape of the lens. When the ciliary body contracts, it releases tension of the suspensory ligaments, and the lens thickens. When the ciliary body relaxes, the suspensory ligaments tension and the lens narrow.
How are congenital cataracts screened for?
The red reflex is tested during the neonatal exammination
Risk factors for cataracts
-increasing age
-smoking
-alcohol
-diabetes
-steroids
-hypocalcaemia
Cataracts presentation
-symptoms are usually asymmetrical
-slow reduction in visual acuity
-progressive blurring of vision
-colours become more faded, brown or yellow
-starbursts can appear around lights, particularly at night
-loss of the red reflex
-lens can appear grey or white using an ophthalmoscope
Management of cataracts
-no intervention may be necessary if the symptoms are manageable
-cataract surgery- artificial lens
Why may patients still have reduced visual acuity after cataract surgery?
Cataracts can prevent the detection of other pathology, such as macular degeneration or diabetic retinopathy, which can become apparent after surgery.
What is endophthalmitis?
Endophthalmitis describes inflammation of the inner contents of the eye, usually caused by infections, and is a rare but serious complication of cataract surgery. It can lead to vision loss. It is treated with intravitreal antibiotics.
Where is the anterior chamber of the eye?
Between the cornea and iris