Ophthalmology Flashcards
Conjunctivitis
- aetiology: define, types, risk factors, stages
- clinical features
- investigations
- management
- prognosis + complication
Inflam of conjunctiva (mucous membrane lining eyelids and sclera)
Causes:
- Bacterial : staph.aureus, haemophilius influenzae, pneumococcus and moraxella catarrhalis
- Virsu: adenovirus, herpes simplex, epstein-barr, varicaella zoster, molluscum contagiosum, coxsackie, enteroviruses
- allergic reactions
- mechanical irritation
- meds
CLINICAL FEATURES
- Red eye due to ocular hyperemia
- Discharge (purulent if bacterial or watery if viral or mucoid/ropy if allergy) and crust formation
- Itching (most intense in seasonal allergic conjunctivitis)
- Eyelid swelling
- Photophobia
- Eyelids stuck together in morning
- pre-auricular (common in viral)
Bacterial conjunctivitus:
- Unilateral, thick purulent discharge (yellow crusting)
- Eyes may be stuck together in morning
Viral conjunctivitus:
- bilateral (begins unilateral), clear watery discharge
- Recent URTI
Allergic:
- Clear watery discharge
- Itchiness
- May be seasonal or due to specific allergen (patient will have history of atopy- eczema, asthma etc)
INVESTIGATIONS
- Rapid adenovirus immunoassay (positive in viral)
- Cell culture & gram stain
MANAGEMENT
Viral:
- Topical antivirals
- Antihistamine drops: epinastine ophthalmic, azelastine ophthalmic, naphazoline/pheniramine ophthalmic
- Supportive care
Bacterial:
- topical broad spectrum antibiotics- such as erythromycin, azithromycin, or polymyxin/trimethoprim
??? chloramphenicol or topical fusidic acid for pregnant women????
- Topical fluoroquinolone (ciprofloxacin/levofloxacin)
Allergics
- Topical antihistamines:e.g., epinastine, azelastine, pheniramine, alcaftadine)
- Avoid allergen
- Cold compress
General advice:
- dont wear contact lense
- dont share towels
COMPLICATIONS
- Dry eyes
- Keratitis
- Subepithelial corneal infiltrates
Optic neuritis
- aetiology: define, types, risk factors, stages
- clinical features
- investigations
- management
- prognosis + complication
Inflammation of the optic nerve
Most common in MS
affects women 30-50 years old the most
CLINICAL FEATURES
- Vision loss- relatively quick, over hours to days
- Decrease in visual acuity over days-weeks with scotoma (like seeing through fog)
- Peri-orbital pain exacerbated by eye movements
- Colour desaturation- colours not as bright as before
- RAPD (relative afferent pupillary defect) on swinging light test- both pupils dilate when bright light swung from unaffected eye to affected eye. This happens because when light shining on unaffected eye both pupils constrict coz afferent path working but when we shift to affected eye, optic nerve (afferent path) injured so both pupils dilate instead of constricting
- Optic disk swelling (papillitis)
- MS symptoms
INVESTIGATIONS
Gadolinium enhanced MRI of orbit and brain
See enlarged optic nerve and helps to diangose MS
Swinging light test
MANAGEMENT
High dose corticosteroids (prednisolone), takes 4-6 weeks
If has inflam disease: CCS but also immunosuppression (azathioprine, cyclophosphamide)
COMPLICATIONS
- MS development
- recurrent optic neuritis
- chronically reduced visual acuity
Periorbital and orbital cellulitis
- aetiology: define, types, risk factors, stages
- clinical features
- investigations
- management
- prognosis + complication
Periorobital cellulitis: inflam and infection of superficial eyelid which may lead to orbital cellultis. Infection comes from a superficial site of inoculation like insect bite
Orbital cellulitis is infection within orbital soft tissues- its more serious and requires admission. Often due to URTI spread especially sinusitis, or orbital injury
Common in males and twice as common in children
Causative organisms:
- Staph aureus
- Staph epidermidis
- Strep species
- Anaerobes
RF:
- Previous sinus infection (sinusitis)
- Lack of H influenza type b vaccination
- Insect bite on eyelid (periorbital)
CLINICAL FEATURES
Periorbital cellulitis:
- Red, swollen, painful eye of acute onset
- Eyelid oedema and erythema
- Insect bite on eyelid
- Stye
Orbital Cellulitis: (first three are distiguishing)
- Visual disturbance
- Pain with eye movements (ophthalmoplegia)
- Proptosis (eye bulging)
- Redness and swelling around eye
- Severe ocular pain
- Eyelid oedema
INVESTIGATIONS
if suspect orbital cellulitis: CT sinus and orbits with contrast - will see inflam of periorbital or orbital tissue to differentiate between both. Must assess for posterior spread of infection
Bloods: high WBC
Blood culture and swab to detect organism
MANAGEMENT
Orbital: Hospital admission and ENT review. IV ABx (vacomycin + cefotaxime+ clindamycin if MRSA resistant, cefo or clind if not), do before the CT
Periorbital: dont need amission but same ABx as orbital
periorbital: Oral co-amoxiclav (co-amoxicalv can cause erythema multiforme and cholestasis) and secondary care referral
Prognosis:
periorbital better in 1-2 days
Orbital- after ABX for 2 days will then see improvement, if no response in 1-2 days dont worry, if no response or have new signs like decreased vision or RAPD, redo CT and suspect absess or resistant organism
COMPLICATIONS
- Cavernous sinus thrombosis
- Orbital abscess
- Blindness
- Brain abscess
Scleritis
- aetiology: define, types, risk factors, stages
- clinical features
- investigations
- management
- prognosis + complication
Transmural inflammation of sclera
Females 40-60
May have underlying systemic disorder or infection
- Commonly RA
- SLE
- sarcoid
- IBD
- gout
Episcleritis: IBS, RA
CLINICAL FEATURES
- Deep, aching, boring eye pain exacerbated by eye movement and palpation, may radiate to rest of face
- Red eye
- Photophobia
- Lacrimation
Episcleritis is PAINLESS red eye
INVESTIGATIONS
Phenylephrine drops - if eye redness improves then episcleritis not scleritis
US scan to look for posterior scleritis
Orbital CT/MRI to differentiate between orbital lesions
Systemic diseases like RA and ANA
MANAGEMENT
Urgent/same day referral to opthalmologist (threat to sight)
1st line NSAIDs
2nd Systemic glucocorticoids
3rd Systemic immunosuppressive therapy (azathioprine, methotrexate)
Episcleritis: conservative
COMPLICATIONS
perforation of the globe
Thyroid eye disease
- aetiology: define, types, risk factors, stages
- clinical features
- investigations
- management
- prognosis + complication
Graves (hyperthyroid), 25-50% of graves pts will get, usually female.
Risk Factor: smoking
Autoimmune response against TSH receptor leads to retro-orbital inflammation
Autoantibodies target extraocular muscles causing swelling behind eye resulting in eye proptosis
Inflammation results in glycosaminoglycan and collagen deposition in muscles
CLINICAL FEATURES
- Patients may be eu, hypo or hyperthyroid
- Exophthalmos
- Lid lag- upper eyelid is higher than normal with globe in downgaze
- Conjunctival oedema
- Optic disc swelling
- Ophthalmoplegia- paralysis of muscles surrounding eye
- cant close eyelids so : dry-eyes which can cause Exposure keratopathy (damage to cornea)
INVESTIGATIONS
Low TSH, high T3/4
High TSH receptor antibodies
MANAGEMENT
Urgent review by ophthalmologist
Smoking- can worsen it
Inflammation:
- topical lubricants to prevent corneal inflammation caused by exposure
- High dose IV steroids (prednisolone)
Hyperthyroidism treatment: Thionamides, radiotherapy, surgery
Uveitis
- aetiology: define, types, risk factors, stages
- clinical features
- investigations
- management
- prognosis + complication
Inflammation of 1 or all parts of uvea (middle vascular layer of eye between retina and sclera)
Anterior uveitis: iris (iritis) and ciliary body usually affected. Associated with HLA-B27 gene. Idiotpathic or non-infectious causes (autoimmune: RA, ankylosing spondylitis, MS, IBS, sarcoidosis)
Posterior uveitis: Choroid, retina and retinal vasculature usually affected. Caused by HSV, Varicella zoster, HIV, lyme disease, TB
Intermediate uveitis: Posterior ciliary body and pars plana
Panuveitis: Inflammation in all 3 segments
RF:
- Inflammatory diseases
- HLA-B27 positivity
- Ocular trauma
- Immunosuppression
CLINICAL FEATURES
Anterior uveitis:
- Acute progressive dull pain in orbital region
- Red eye with no discharge
- Synechiae (iris stuck to cornea or lens)
- Photophobia
- Decreased visual acuity (blurred)
- Increased lacrimation
- Hypopyon (pus accumulation in anterior chamber resulting in visible fluid level)
- Constricted & fixed, non reactive oval pupil
- No pain on eye movement as with scleritis, orbital cellulitis and optic neuritis
- No discharge
Posterior uveitis:
- Painless visual disturbances
- Floaters
- Decreased visual acuity (blurred)
INVESTIGATIONS
Clinical diagnosis
MANAGEMENT
1st
- Corticosteroid eye drops (prednisolone) to reduce inflammation
- Urgent review by ophthalmologist
Photophobia and pain- cyclopegic eye drops (atropine) to dilate pupil
Infection- ABx or antiviral
COMPLICATIONS
- Cataract
- Macular oedema
- Glaucoma
- Band keratopathy
- Synechiae
PROGNOSIS: risk of blindness unilateral/bilateral or visual loss. Depends on severity, location ect
