Eye problems and stuff Flashcards
Age-related macular degeneration (ARMD)
- Describes degeneration of photoreceptors in the central retina (macula) that leads to the formation of drusen, which are visible on slit-lamp biomicroscopy
Lecturer says:
- Cause unknown, multifactotrial (risk factors = increasing age, smoking, positive fam history, poor nutrition etc)
- Leading cause of blindness in the UK
- Patients present with subacute loss of and/or distortion of the central visual field
- Subtypes: dry (most common - gradual), wet (sudden vision loss)
Dry ARMD
Symptoms:
- Gradual vision loss
- Central vision ‘missing’ (Scotoma)
Signs:
– Drusen = Dry (build up of waste products below RPE)
- Atrophic patch of retina (retinal cells die off aka macular thinning)
Treatment:
- No cure => Supportive
- Low vision aids e.g. magnifiers
- Visual impairment registration
- Social support
Wet ARMD
- Neovascularisation - new blood vessels grow under retina => leakage => build up of fluid/blood => scarring
- rapid progression over months, poor prognosis
Symptoms:
- Rapid central vision loss
- Distortion (metamorphsia)
Signs:
- Haemorrhage/exudate
Cataracts
Opacity/cloudiness of the lens
Cause:
- Denaturation of lens proteins (ctystallins) => loss of transparecy
- Primarily prevalent among the elderly, cataracts can also be congenital, metabolic, drug-induced (steroids) and trauma
- Many diff types e.g. nuclear cataract. posterior subcapsular cataract, Christmas tree cataract (aka polychromatic cataract), Mature cataract
- No. 1 cause of blindness worldwide
Symptoms/signs:
- Gradual visual loss (‘hazy’/’blurred’)
- Glare
- Loss of red reflex
Management:
- Surgical removal (phacoemulsification) with intra-ocular lens implant if patient symptomatic
Conjunctivitis
- Also known as ““pink eye”
- common condition that involves inflammation or infection of the conjunctiva, the transparent membrane that lines the eyelid and covers the white part of the eye
- Can be either infectious (caused by bacteria or viruses) or noninfectious (due to allergies or other irritants).
Allergic conjunctivitis
Type I hypersensitivity reaction to allergens in the environment. Common triggers include pollen, dust mites, and pet dander.
Viral conjunctivitis
Most often caused by adenoviruses but can also be caused by herpes simplex virus. It is highly contagious and often associated with upper respiratory tract infections or colds.
second most common subtype
Bacterial conjunctivitis
Common pathogens include Staphylococcus aureus, Streptococcus pneumoniae, Haemophilus influenzae, and Moraxella catarrhalis.
Sexually transmitted infections like gonorrhea or chlamydia can also cause bacterial conjunctivitis.
A common presenting complaint is that of the eyelids being ‘stuck’ together in the morning.
Bell’s palsy
- Idiopathic syndrome that causes damage to the facial nerve.
- Unilateral, lower motor neuron facial weakness, without sparing the extraocular muscles and muscles of mastication.
- Presents with mild-moderate postauricular otalgia, hyperacusis (rare), and nervus intermedius symptoms such as altered taste and dry eyes/mouth.
3 key questions when assessing red eye
- Is acuinity affected? (how sharp things appear/clarity)
- Is the eye painful?
- Are pupil reflexes affected?
Hypopyon
An accumulation of pus cells in anterior chamber, with a visible fluid level.
Differences between Episcleritis and Scleritis
In episcleritis pain is often mild, severe pain should raise the suspicion of scleritis. Also, scleral vessels do not move or blanch whereas episcleral vessels do when pressed with a cotton bud.
Scleritis = sight-threatening
Episcleritis = non-sight threatening
Scleritis
- A severe inflammation of the sclera
- May be associated with systemic illnesses such as rheumatoid arthritis or granulomatosis with polyangiitis
- Red eye
- Severe pain in the orbit
- Pain on eye movement
- Bluish tinge to the white of the eye in severe or necrotising scleritis
- Systemic symptoms in ~50% of patients
Episcleritis
- An inflammation of the episclera, the layer underneath the conjunctiva
- Sectoral redness
- Tenderness over the inflamed area
- Milder pain compared to scleritis
- Episcleral vessels move or blanch when pressed with a cotton bud
Bacterial Keratisis
- Opthalmic emergency
- Bacterial infection of the cornea
- Typically in contact lens users with Pseudomonas aeruginosa
Signs/Symptoms
- Severe eye pain, decreased vision, light sensitivity, and discharge
- sensation of something in the eye
- Administer intensive topical quinolone (and sometimes oral) antibiotics.
- Sometimes cyclopentolate is used for pain relief.
Horner’s syndrome
- A collection of signs and symptoms that result from an impairment to the sympathetic nerve supply to the eye.
- Key signs and symptoms include ptosis (drooping of the upper eyelid), miosis (constriction of the pupil), and anhidrosis (lack of sweating) on the affected side
- Treat underlying cause e.g. pancoast tumour or carotid artery dissection
-Can be categorised into pre-ganglionic, post-ganglionic, and central causes, depending on the location of the sympathetic nerve interruption.
Herpes simplex keratitddies
- Severe eye infection caused by reactivation of the herpes simplex virus type 1 in the trigeminal ganglion
- Primarily affects the cornea, leading to discomfort, visual distortion, and in severe cases, blindness
Signs/Symptoms
- Acute pain
- Photophobia (sensitivity to light)
- Epiphora (excessive tearing) Under slit lamp examination with fluorescein staining, pathognomonic DENDRITIC ulcers might be observed.
Treatment
- Topical anti-viral e.g. acyclovir - try control infection and prevent corneal scarring (can lead to blindness)
Fungal keratitis
Signs/Symptoms
- eye pain, redness, blurred vision, discharge, and decreased vision.
Acanthamoeba keratitis
- More common if history of submergence in contaminated water (swimming/lakes/hot tubs) or eye exposure to soil and contact lens use
Signs/Symptoms
- Eye pain, red eye, blurred vision, light sensitivity, and a feeling of something in the eye.
Basal Cell Carcinoma (BCC) of the eyelid
- Skin cancer that commonly effects the lower eyelid - doesnt metastasise but complications are through local invasion
- accounts for about 90% of eyelid malignancies
Endophthalmitis
- Severe inflammation in the inside of the eye, commonly resulting from an infection = sight-threatening
- Primarily occurs post-surgery, although rare endogenous infections can also seed to the eye
- Most common cause is gram-positive (Particularly staphylococcus) bacteria = Intravitreal Vancomycin
Key signs/symptoms:
- Red eye
- Eye pain
- Decreased visual acuity
- Photophobia
- Floaters
- Hypopyon (pus collection in anterior chamber)
Retinitis pigmentosa (RP)
A group of inherited disorders that cause degeneration of the rod photoreceptor cells in the retina => progressive peripheral vision loss and night blindness due to the
Main features:
- Tunnel vision (loss of central vison in later stages)
- Reduced visual acuity in dim light
- Young age at presentation
Symptoms include:
- floaters, blurred vision, and progressive loss of peripheral vision
Uveitis
Uveitis is an umbrella term for conditions causing inflammation of the uveal tract, including the iris, ciliary body, and choroid, along with associated structures in the eye.
Four types: anterior uveitis, intermediate uveitis, posterior uveitis, and panuveitis, based on the anatomical location of inflammation.
Anterior uveitis is the most prevalent type
Typical presentation:
- Red eye, pain, blurred vision and photophobia.
- The pupil may be irregular due to adhesions between the lens and iris (termed synechiae).
Uveitis results from various underlying disease processes, including:
- Autoimmune diseases
- Infection e.g. herpes, TB, syphilis, HIV
- Trauma
- Iatrogenic
- Ischaemic conditions
Pterygium
The pathological overgrowth of the conjunctiva, a clear membrane covering the white part of the eye, onto the cornea’s surface, the clear front surface of the eye, often presenting as a white fibrous opacity.
Common symptoms include:
- reduced visual acuity and eye irritation.
When someone presents with eye pain what 4 diagnoses must be ruled out?
- Acute angle-closure glaucoma
- Anterior uveitis
- Scleritis
- Corneal ulcer
Acute angle-closure glaucoma/Primary angle closure glaucoma (PACG) - this is a biggy
Medical Emergency - refer urgently to opthalmology as it is sight-threatening
Normal aqueous flow through pupil is disrupted => increase in pressure gradient causes periphera; iris to bow forward, obstructing the trabecular meshwork - pressure increases abruptly
aka a Blockage or narrowing of the drainage angle formed by the cornea and the iris, resulting in a sudden increase in intraocular pressure => damage to optic nerve
Risk factors:
- Older Age
- Asian or Inuit populations (female??)
- Long-sightedness (Hyperopia)
Symptoms:
- Painful eye
- Headache
- Blurred vision –> sudden vision loss
-Haloes – patients will often describe coloured haloes around lights - Nausea and vomiting
Signs:
- Red eye – ciliary flush
- Cloudy cornea
- Mid-dilated or fixed pupil
- Closed iridocorneal angles on gonioscopy
- Corneal oedema
- Raised IOP (defined as >21 mmHg) – the eye may feel hard on palpation
Management:
- Lower IOP with drops, oral/IV mediation & laser to prevent irreversible blindness
Cluster headache
Classically involves daily episodes of pain around one eye that occur in clusters of 1-3 months. Associated symptoms are red eye, lacrimation and swelling. In some, the pupil is in a fixed constricted position.
Corneal abrasion
- Damage to the corneal epithelium, as opposed to a corneal ulcer which refers to a deeper breach. -
- Patients present with pain, photophobia and possibly reduced visual acuity.
- Often they mention obvious trauma/injury to the eye, or they may belong to a profession that puts them at risk – such as sheet metal working
Thyroid eye disease (TED)
A complication of Grave’s disease, which is an autoimmune hyperthyroidism.
An inflammatory process results in swelling of the extraocular muscles and orbital fat, which leads to multiple ocular complications.
It manifests with a range of ocular symptoms, including eyelid retraction, proptosis, double vision, and ocular discomfort
Kayser-Fleischer rings
Copper coloured rings around the periphery of the cornea. They are due to copper deposition in the cornea and are associated with a number of conditions e.g. Wilsons disease, cholestasis, primary biliary cirrhosis
Chronic open angle glaucoma
A form of optic neuropathy characterized by the death of optic nerve fibres, either with or without raised intraocular pressure (IOP).
Over time, glaucoma can lead to characteristic changes in the visual field.
Pathophysiology:
- Impaired aqueous humor drainage through the trabecular meshwork, causing elevated intraocular pressure (IOP).
- This pressure gradually damages the optic nerve and leads to peripheral visual field loss.
- Unlike acute closed-angle glaucoma, where the drainage angle is suddenly blocked, open-angle glaucoma has a slower, insidious onset, allowing for a more gradual increase in IOP.
Risk factors:
- Raised IOP – key modifiable risk factor
- Hypertension
- Diabetes mellitus
- Corticosteroids
Symptoms:
- Often NONE
- Nay be discovered by optician
Signs:
- May/May not have high IOP
- Cupped disc (= loss of retinal ganglion cells aka a large optic cup, the paler part is larger, outside less ‘meaty’ which is the part with the ganglions)
- Visual filed defect (i.e. a thin inferior rim corresponds to superior field loss)
Patient may be asymptomatic because:
- Gradual onset
- Visual field loss is often peripheral
- Disease may be asymmetric: if one eye is badly effected, the other ‘better’ eye can compensate as our visual fields overlap
Glaucoma
Glaucoma = optic nerve damage due to pressure/fluid build up in the eye
Either open or closed Glaucoma - both sight-threatening
Open: Slower progressing
Closed: Acute, medical emergency
Chemosis
swelling of the conjunctiva
Orbital cellulitis
A sight- and life-threatening emergency
Infection of the structures behind the orbital septum.
The orbital septum is a membranous sheet that forms the anterior border of the orbit, extending from the orbital rims (superior and inferior) and into the eyelids
Important findings that suggest preseptal cellulitis, rather than orbital cellulitis, are:
- No proptosis
- Normal eye movements
- No chemosis
- Normal optic nerve function
