Ophthalmology Flashcards
Blepharitis:
- common associations?
- features? (6)
- management? (3)
Anterior: seborrhoeic dermatitis, rosacea, staph infection
Posterior: meibomian gland dysfunction
Usually unilateral
Grittiness and discomfort
Sticky eyes in morning
Eyelid may be red, usually swollen in staph infection
Styes and chalazions more common with blepharitis
Secondary conjunctivitis may occur
Rx:
- Hot compress twice a day on lid margin
- Remove debris with cotton wool dipped in cooled boiled water with baby shampoo OR flush eyes with cooled boiled water with sodium bicarb
- Artificial tears for symptomatic dry eyes
Commonest cause of blindness in UK?
RF?
Types?
ARMD - degeneration of central photoreceptors with formation of drusen
- Age
- Smoking
- FHx
Dry:
- Atrophic, drusen around Bruch’s membrane
Wet:
- exudative
- choroidal neovascularisation which can leak, worse prognosis
- The new vessels are typically intra- or sub-retinal
Symptoms of ARMD?
Signs?
Ix?
- reduced acuity for near objects
- dark vision deterioration
- vision may vary day to day
- May see flashing lights and glare around objects
Signs:
- Amsler test grid - distortion of lines
- Macular drusen if dry, can fuse to form a macular scar in late disease
- Demarcared red patches in wet
Ix:
1st line - slit lamp
2nd line - fluorescein angiography if wet suspected
Management of ARMD?
Monitoring?
Zinc and Vits A, C and E (anti-oxidants) - slow progression by 1/3
anti-VEFF if wet - 4 weekly injections
Laser photocoagulation can also be used for wet, but increased risk of acute visual loss
Monitoring:
Amsler grid to measure line distortion perception
Where does nasoplacrimal duct open into?
Muscles of the iris?
Cones and Rods?
Inferior meatus
Sphinctor pupillae (parasympathetic - constricts) Dilator pupillae (sympathetic - dilates)
Cones - coloured vision (coloured)
Rods - dim vision, black & white (peripheral)
Extra-ocular muscles?
LR 6
SO 4
AO 3
IO pulls it up and in
SO pulls it down and in
(obliques move in adducted plane, rectus muscles move in abducted)
LPS 3 + sympathetic (mullers muscle)
Afferent and efferent limbs:
- corneal reflex?
- pupillary light reflex?
- lacrimation?
- accommodation?
Corneal:
- afferent CNV1
- efferent CNVII
Pupillary light:
- afferent CN II
- efferent CNIII
Lacrimation
- afferent CNV1
- efferent CNVII
Accommodation:
- afferent CNII
- efferent CNIII
Nerves containing:
- preganglionic parasympathetic?
- parasympathetic nucleus?
- sympathetic?
Modalities of:
- short ciliary nerve?
- long ciliary nerve?
- CNIII
- Edinger Westphal nucleus in midbrain
- Sympathetic chain
Short: sensory + sympathetic
Long: sympathetic, parasympathetic, sensory
Accommodation reflex what happens when looking close?
When looking far away?
3 things it tests?
Afferent CNII Efferent CNIII (para)
Focusing up close, makes lens round:
- increased parasympathetic to ciliary body (long nerve)
- contraction of ciliary body moves it closer to lens
- Suspensory ligaments relax, allowing lens to become round
Focusing far away, makes lens flat:
- Decreased parasympathetic output
- Relaxation of ciliary body, moves it further away from lens
- Suspensory ligaments tighten, making lens lens flat
Tests 3 things:
- pupil constriction
- lens accommodation
- convergence
Most common cause of viral conjunctivitis?
What points towards viral?
Adenovirus
4 things:
- bilateral from offset (instead of unilateral then bi)
- watery discharge
- Follicular inflammation (instead of papillary)
- pre-auricular lymph nodes
Management of conjunctivitis?
Usually self resolves in 1-2 weeks, abx are quicker if bacterial
Chloramphenicol 1st line
Fusidic acid if pregnant/young
What points towards allergic conjunctivitis?
Management?
Seasonal
Itch
Swollen papillae w cobblestone appearance of conjunctivae (cheimosis)
What causes cotton wool spots?
Areas of infarction due to pre-capillary arteriolar occlusion
Causes of papilloedema?
SOL - neoplastic/vascular Malignant hypertension Idiopathic intracranial hypertension Hydrocephalus Hypercapnia (induced hyperventilation a treatment for raised ICP) low Ca Hypoparathyroidism VitA toxicity
Causes of vitreous haemorrhage?
Prognosis?
Diabetic/hypertensive retinopathy causing unstable vasculature
Anti-coagulant use
Trauma
Resolves with time
Treatment of herpes zoster ophthalmicus?
What eye complications can it have?
Aciclovir for 7-10 days ideally within 72 hours (IV if immunocompromised)
Topical steroids if any eye inflammation -> urgent ophthalmology review
Comps:
- conjunctivitis, keratitis, episcleritis, anterior uveitis
- post-herpetic neuralgia
Ix orbital cellulitis?
Management?
CT contrast
Admit for IV abx
4 grades of hypertensive retinopathy?
SAFE
- Silver wiring, tortuosity
2, AV nipping - Flame haemorrhages and cotton wool spots
- papilloEdema
Argyll-Robertson pupil?
Causes?
Bilateral small pupils that constrict to accommodate but don’t react to bright light
Diabetes
Neurosyphilis
Holmes-Adie pupil?
Causes?
Dilated pupil, usually unilateral
Once it constricts it stays small for a long time
Slowly constricts to accommodation but very poor/no reaction to light
Causes:
- Can be idiopathic in females, assoc w missing knee and ankle reflexes
- Can be caused by damaged parasympathetic innervation from viral/bacterial infection
Marcus-Gunn pupil?
RAPD
Most commonly in optic neuritis or severe retinal disease
Hutchison’s pupil?
Causes?
Unilateral dilated pupil unresponsive to light
Due to ipsilateral compression of CNIII by tumour/haematoma
open angle glaucoma
1st line - Prostaglandin analogues +/- B blockers
2nd line - CAI, alpha agonists (sympathomimetics)
Horner’s syndrome and ipsilateral facial pain?
Carotid artery dissection
