Acute Anterior Eye Conditions Flashcards
What is an emergency in eyecare?
CoO: “no legal definition of emergency – may include: red eye, recent loss of vision, recent onset of ocular pain, symptoms which strongly suggest a recent retinal tear or detachment, or giant cell (temporal) arteritis (GCA)”
What does CoO say to do if emergency presents?
- “You must assess the patient and decide on the best course of action. The specific action will depend on the situation and you must use your professional judgement to decide what is in the best interests of the patient.
- If you conduct an emergency examination of a patient who presents with an acute condition, you should make it clear to the patient that it is not a statutory sight test or full eye examination and that you are only addressing the presenting symptoms. You should:
o record all findings and any advice you give the patient
o make it clear that the patient should return to their usual optometrist for a routine eye examination when it is due, and
o refer the patient to an appropriate healthcare professional if applicable. - If you decide not to conduct an emergency examination of a patient who presents with an acute condition you should: direct the patient to an appropriate healthcare professional, and indicate the degree of urgency”
Many health boards advocate the use of triage form by practice staff.
Optometrists then use their clinical judgement to determine any action needed, and urgency of this action
How does a chemical injury present? Give examples of alkalis, acids and solvents that could cause it?
- Presentation - Most commonly following household cleaning/DIY or industrial/manual work
- Common causative agents
- Alkalis, such as:
o ammonia compounds (household cleaners, fertiliser)
o sodium hydroxide (drain and oven cleaners)
o calcium hydroxide -lime (cement, plaster) - Alkaline agents are particularly damaging as they have both hydrophilic and lipophilic properties, which allow them to rapidly penetrate cell membranes and enter the anterior chamber. Alkali damage results from interaction of the hydroxyl ions causing saponification of cell membranes and cell death along with disruption of the extracellular matrix
- Acids, such as:
o sulphuric (car batteries)
o hydrofluoric (glass etching)
o hydrochloric (>25% is corrosive)
o glacial acetic (wart, verruca treatment - rarely)
o citric (limescale removal) - Acids tend to cause less damage than alkalis as many corneal proteins bind acid and act as a chemical buffer. In addition, coagulated tissue acts as a barrier to further penetration of acid. Acid binds to collagen and causes fibril shrinkage.
- Also Detergents, such as:
o free chlorine liberating compounds including sodium hypochlorite (bleach) - Solvents, such as:
o paint thinners
o petrol
o nail varnish remover
o Fixatives, such as:
o formaldehyde
o glutaraldehyde
What are the signs of chemical injury?
- Burns to eyelids and surrounding skin
- Particulate matter under lid (evert to examine)
- Conjunctival chemosis and hyperaemia
- Limbal and conjunctival blanching (cessation of blood flow in superficial vessels; may indicate poor prognosis) – key sign to look for – irrigate v thoroughly if this is the case
- Corneal epithelial defects ranging from superficial punctate keratitis through focal epithelial loss to sloughing of the entire epithelium
- Corneal oedema and opacification in severe cases (may prevent view of anterior chamber, iris, lens or beyond) – specifically if been there for a few hours/days
- Raised IOP
- Various chemical trauma classification systems exist, e.g. those of Roper-Hall and Dua and the ILSI classification. Each of these establishes limbal ischaemia as dividing mild from more severe trauma
What is the treatment for chemical injury and why do you refer? What are the red flags?
- Evert lids to remove any particulate matter
- Irrigate, irrigate, irrigate
- ASAP and for at least 15-30min
- Sterile saline, if not tap water
Trying to neutralise the pH of the eye as quickly as possible - So eye can be irrigated until reaches pH 7
- And to repair any damage
- Indicators of poor prognosis
o Limbal blanching of more than 270 degrees
o loss of corneal, limbal and conjunctival epithelium
Describe blunt trauma and the symptoms/signs?
Accidental (e.g. RTA, industrial, domestic, sports) or non-accidental (e.g. fist)
Presentation can be v variable symptoms are variable depending on severity of blunt trauma
* Blow to the eye – deliberate/accidental – in children there may be little bruising
* Signs indicating urgent referral needed
o infraorbital nerve anaesthesia (can’t feel lower lid, cheek, side of nose, upper lip, teeth), enophthalmos (sunken eye), diplopia in up or downgaze may indicate orbital fracture
Ask px if any areas that feel numb?
Do motility to check movement full or if there is infraorbital floor fracture
o nasal bleeding (direct trauma, or could indicate skull fracture)
o relative afferent pupillary defect (indicates traumatic optic neuropathy)
* Symptoms:
o Pain varies from mild to severe
o Epiphora
o Visual loss (variable)
o Photophobia
o Possible diplopia
What are the red flags that may suggest urgent referral?
- Signs indicating urgent referral needed
o corneal oedema or laceration
o AC: hyphaema, uveitis – look for flare and cells
o traumatic mydriasis – likely uniocular, may see tears in iris sphincter muscle which can be seen on retro illumination, Iridodialysis
o lens: evidence of subluxation, cataract, capsule damage – any damage to zonules
o IOP increase or decrease
o vitreous haemorrhage
o commotio retinae, retinal detachment or dialysis
o traumatic macular hole
Check health of anterior chamber and then if safe to do so check health of posterior pole to see if there are any signs of serious damage
What is the management of blunt trauma?
- Appropriate and thorough history and thorough investigations to rule out anterior and posterior complications including pupils (see if RAPD), motility, cover test, dilation
- Record mechanism and time of any injury that has occurred
- Management dependent on severity
o Mild cases:
alleviation or palliation; referral unnecessary – review px as necessary – see back in few days to make sure healing
if lots of lid oedema & bruising but don’t see any damage to eye itself then advise cold compresses to ease swelling & advise px to use systemic analgesia e.g. paracetamol or ibuprofen (bear in mind cautions/contraindications) – can keep px more comfortable
o Severe cases:
First aid measures and emergency (same day) referral to A&E
What are the key features, sources and predisposing factors of photokeratitis?
- Key Features
o Exposure to UVB or UVC
o Delayed onset of symptoms
o Pain/photophobia/blepharospasm/lacrimation/blurred vision
o Punctate staining of epithelium
o Associated skin burns from UV exposure
Sources: welding arcs, sun (including reflection from snow or water – skiiers especially at risk), tanning lamps e.g. tanning beds, therapeutic high intensity UV (for skin conditions or seasonal affective disorder), germicidal UV lamps, other sources of UVB or UVC
Absorption of radiation by corneal epithelium causing punctate erosions
Predisposing factors: Lack of suitable eye protection
What are the symptoms and signs of photokeratitis?
Symptoms:
* Delay of 6-12 hours between exposure and onset of symptoms is usual; however, latency varies inversely with exposure dose and can be as short as 1 hour
* Mild cases:
o irritation and foreign body sensation
* Severe cases:
o pain
o redness
o photophobia
o blepharospasm
o lacrimation
o blurring of vision
Signs:
* Bilateral (if unilateral, suspect corneal or subtarsal foreign body)
* Lid chemosis and redness
* Conjunctival hyperaemia
* Epiphora
* Punctate staining of corneal epithelium with fluorescein (may be coalescent)
* Mild transitory visual loss
* Associated skin burns from UV exposure
* Image: LHS: some coalescent staining and some punctate staining – px will have some discomfort as result. RHS: more extensive punctate staining over cornea – probably why eye is not fully open in this image
What is the management of photokeratitis?
- Non-pharmacological:
o Patient counselling - rest with eyes closed as much as possible until resolution, sunglasses, cold compresses, future eye protection - Pharmacological:
o Local anaesthetic only to aid examination, tear supplements (preferably unpreserved), un-medicated ointment, oral analgesic for pain relief
MUST not give anaesthetic for use outside of practice
o In more severe cases
If infection risk high may consider prophylactic antibiotic
If significant corneal epithelial defect may consider cycloplegia to alleviate ciliary spasm
What should you ask in history and what should you check in corneal foreign body?
History:
* Onset (acute / gradual), Duration, Nature of symptoms.
o (What happened in Pxs own words.)
* Nature of foreign body if known; metallic, mascara, organic.
o Organic FB has higher risk of fungal infection
* Pain; severity, nature (dull or sharp) worsening or improving, worse on blinking, constant, deep, throbbing etc. (use 10-point scale).
* Photophobia.
* Blepharospasm
* Lacrimation.
* Discharge/stickiness: (Nature watery, purulent, colour etc).
Check:
* VA before and after FB removal
* globe and adnexae for signs of penetration
* where there is any suspicion of a penetrating injury, carry out dilated fundus examination
* AC for flare or cells
What are the red flags of corneal foreign body?
- High velocity object strong suspicion of penetration of the globe – e.g. if drilling/grinding metal
- Note any signs such as lid laceration or anterior segment damage – does lens look intact?
- Any signs of penetrating injury then dilate and check for cells/flare
- Siderosis - from intraocular steel foreign body – deposition of iron on anterior capsule of lens, tends to be radially distributed reddish/brown deposits on lens & can get reddish staining of iris resulting in heterochromia
o Can get pigmentary retinopathy followed by atrophy of RP and retina as result of metal entering and being retained in the eye - Vegetative foreign body more likely to lead to fungal infection – can have more dire consequences and is more difficult to treat so treat in secondary care
SUPERFICIAL OR PENETRATING? Use Seidel’s Test – high conc NaFl to see if any leakage from AC
Consider double lid eversion to rule out secondary FBs in the superior fornix
What is the management of corneal foreign body?
- Non-pharmacological:
o Rule out multiple particles – cornea, conjunctiva (bulbar, fornix, palpebral): double evert lids
o Loose foreign body can be irrigated away with normal saline
o Foreign body on conjunctiva can be removed with a sterile cotton bud
o Corneal foreign body may require removal with a hypodermic needle or other disposable instrument.
To reduce the risk of corneal penetration, ensure that the needle approaches the cornea tangentially
o After removal, assess size of remaining epithelial defect so that healing can be monitored
And determine if prophylactic antibiotics are required - Removing a foreign body:
o MUST check VA before and after corneal FB removal
Get comfortable removing peripheral FBs before trying FBs on visual axis
o Check for signs of penetration – do Seidel’s test & check depth of lesion
If FB in epithelium then can proceed to try and remove refer if deeper
o Needle tangential to cornea
o Needle sharp edge slid under the edge of foreign body and scrape out and away from central cornea
o Alger burr to remove any residual rust – should limit chance of any siderosis taking hold - Pharmacological:
o Remove foreign body under topical anaesthesia
Consider use of ointment (unmedicated or medicated) following removal (as ocular lubrication) – to aid epithelium healing
o If there is a likelihood of infection, consider topical antibiotic prophylaxis (e.g. gutt. chloramphenicol 0.5% qds for 5 days)
o For large epithelial defects, cycloplegia to prevent pupil spasm (e.g. gutt cyclopentolate 1% twice daily until healed)
What should you remember in corneal abrasion?
- Ensure you evert lids to check for retained subtarsal FB especially important where may suspect multiple FBs from history
- Pay attention to edges of the lesion if rolled edges between epithelial defect and healthy epithelium then indicator of poorer healing – look for ideally defined edges at edge of lesion
- Ocular lubricants to improve comfort & can aid healing process
- Large abrasions or abrasions with associated iritis consider cycloplegia greater than 1/3 size of the cornea then consider or any signs of associated iritis or inflammation within anterior chamber
