Ophthalmology Flashcards
Sudden visual loss (unilateral, painless)
Decreased visual acuity
Dilated pupil (non-reactive)
Pale retina
Cherry-red spot
Diagnosis?
Central Retinal Arterial Occlusion (CRAO)
Tx of CRAO
Lower IOP
- IV Acetazolamide
- Anterior chamber paracentesis
- Digital ocular massage
Vasodilation
- Re-breathe into paper bag (increase CO2)
Emergency referral to Ophthal
Sudden visual loss (unilateral, painless)
Decreased visual acuity
Pale retina
Branch retinal arterial occlusion
How to tell which eye on fundoscopy?
Optic disc is always nasal!
Hold the picture up against their face!
Sudden visual loss (unilateral, painless)
Decreased visual acuity
Retinal haemorrhages (all quadrants)
+/- Neovascularisation
Complete retinal vein occlusion
Sudden visual loss (unilateral, painless)
Decreased visual acuity
Retinal haemorrhages confined to one area
+/- Neovascularisation
Branch retinal vein occlusion
Tx of CRVO
Monitoring for neovascularisation
+/- Laser pan-retinal photocoagulation
Optic pathway
Retina
Optic nerve
Optic chiasm
Optic tracts
Lateral Geniculate Nucleus
Optic radiations (Meyer’s loop and Baum’s loop)
Primary visual cortex
Extra-straiate cortex
Suprior quadrantanopia
Inferior quadrantopia
Lesion?
Tip: PITS (Parietal-Inferior, Temporal-Superior) for Pie in the Sky (PITS) = i.e. quadrantanopia
Superior quadrantanopia ==> Lesion of Temporal lobe
Inferior quadrantanopia ==> Lesion of Parietal lobe
Upper bitemporal hemianopia
vs Lower bitemporal hemianopia
Upper quadrant defect (> Lower) ==> Pituitary adenoma
Lower quadrant defect (> Upper) ==> Craniopharyngioma
Visual field defects
Monocular blindness
Lesion?
Proximal to optic chiasm
Homonymous hemianopia
Lesion?
Contralateral to visual defect (optic tract)
Homonymous hemianopia with macular sparing
Occipital cortex
Pupillary reflex pathway
AFFERENT
- Rod/Cone photoreceptors –> Bipolar cells –> Retinal Ganglion cells
- –> Exit the Optic Tract (BEFORE the Lateral Geniculate Nucleus)
- –> Dorsal Brain Stem
- Afferent pathway from each eye synapses on Edinger-Westphal nuclei on both sides of the brainstem
- ∴ Light shone into either eye will elicit pupillary constriction for BOTH pupils to constrict
EFFERENT
- Edinger-Westphal nuclei
- –> Oculomotor nerve
- –> Ciliary ganglion
- –> Short posterior ciliary nerve
- –> Pupillary sphincter
Pupillary reflex
R sided afferent defect
R sided efferent defect
R sided RAPD
Near response triad
Accommodation (ciliary muscle contracts –> reduce tension –> incr Len’s refractive power)
Miosis
Convergence
Washed out colours
Dimmed vision
Myopia
Loss of red reflex
Nuclear sclerosis cataracts (central)
Glares and Halos
Worsening visual acuity
Loss of red reflex
Cortical cataract (periphery)
Gradual loss of visual acuity
Washed out colour vision
Glare and Halos (worse at night)
Loss of red reflex / White pupil
DIagnosis? Treatment?
Conservative
- Change in glasses prescription
Surgical
- Extracapsular lens extraction
-
Manual extraction and phacoemulsification
- with intraocular lens implant
-
Manual extraction and phacoemulsification
- Post-operative
- Topical ABx
- Topical steroids
Treatment for posterior capsule opacification
(“secondary cataract”)
YAG laser (make a hole in the capsule)
↑ intra-ocular pressure
Optic disc cupping
Notching of optic disc cup (diagnostic)
Visual field changes
Scotoma (early)
Peripheral field loss (late)
Diagnosis? Ix?
Open angle glaucoma
- Ix:
- Fundoscopy: optic disc cupping
- Goldann tonometry: IOP > 21 mmHg (not required for diagnosis)
Tx for open angle glaucoma
(1) Topical eye drops (ABCpD)
- Topical α2-blockers (Apraclonidine, Brimonidine)
- Topical β-blocker (Timolol, Carteolol, Metipranolol, Betaxolol)
- Topical carbonic anhydrase inhibitors (Brinzolamide, Dorzolamide)
- Topical Prostaglandin analogue (Latanoprost, Travoprost, Bimatoprost)
If refractory –> Surgery
- (2) Laser trabeculoplasty
- (3) Trabeculectomy or Drainage tube or Sclerostomy or Viscocanalostomy
Acute, painful red eye
Blurred vision
Halos
Headache
Fixed dilated pupil
Diagnosis? Ix?
Acute closed-angle glaucoma
Ix: Gonioscopy (closed angle)
Tx for acute closed-angle gluaoma
Acute
- (1) IV Acetazolamide
-
or Topical agents (ABC)
- α2 blockers (Apraclonidine)
- β blockers (Timolol)
- Carbonic anhydrase inhibitors (Acetazolamide)
- (2) IV Mannitol (20%)
- (3) Anterior chamber paracentesis
Once stable
- (1) Laser peripheral iridotomy (in both eyes)
- (2) Surgical iridectomy
- (3) Lens extraction
DDx Haloes around lights
Cataracts
Closed-angle glaucoma
Acute vs Closed angle glaucoma
PMHx of Diabetes (proliferative diabetic retinopathy)
Sudden, painless visual loss
New-onset floaters
Diagnosis? Treatment?
Vitreous haemorrhage
Management
- Watchful waiting (resolves within weeks)
- Once stable –> Laser photocoagulation
Acute onset, painless loss of central vision
Age-related macular degeneration
Characteristic changes in Dry and Wet AMD
Dry AMD (most common - 90%)
- Drusen (yellow spots) = hall mark of age-related change
Wet AMD
- Choroidal neovascularisation
- Haemorrhage
Tx of AMD
Dry ADM and early Wet AMD
- Conservative (modify risk factors - stop smoking…etc)
Advanced wet AMD
- Laser photocoagulation
- Intravitreal injections of Anti-VEGF
End stage AMD
- Implantable lens (focus light to functional part of remaining retina)
Diagnosis?
Background diabetic retinopathy
Microaneurysms (dots)
Blot haemorrhages (blots)
Hard exudates
Diagnosis?
Pre-proliferative diabetic retinopathy
Cotton wool spots (sign of ischaemia)
Diagnosis?
Proliferative diabetic retinopathy
Neovascularisation
Diagnosis?
Maculopathy
Hard exudates at macula
SAME as background diabetic retinopathy
But changes at the macula
Stages + Tx of diabetic retinopathy
Stages of hypertensive retinopathy
Diagnosis?
Grade 1 hypertensive retionpathy
Silvery wiring
Diagnosis?
Grade 2 hypertensive retinopathy
AV nipping
Diagnosis?
Grade 3 hypertensive retinopathy
Flame haemorrhages
Cotton wool exudate
Floaters
Flashing lights
Weiss ring (shadow of floaters on retina)
No visual field loss
Diagnosis? Complications?
Posterior vitreous detachment
Complications = Retinal detachment (15%)
Floaters
Flashing lights
Sudden onset, painless, visual field loss
Diagnosis? Ix? Tx?
Retinal detachment
Ix: Slit-lamp examination (diagnostic)
Tx:
- Surgical reattachment
- or laser photocoagulation
- or cryotherapy
Most common cause of inherited blindness
Gradual onset
Decreased visual acuity
Decreased periphearl vision
Fundoscopy = Black spindly lesions across retina
Diagnosis?
Retinitis pigmentosa
Changes in papilloedema
Symptoms
- Blurred vision
Signs
- Venous engorgement
- Loss of venous pulsation
- Blurring of optic disc margins
- “Doughnut” shaped opacity
Causes of RAFD
MS (Optic neuritis) - most common
Severe glaucoma
Trauma
Tumour
Medical CN3 palsy
vs Surgical CN3 palsy
Medical CN3 palsy
- Causes = Diabetes, (Hypertension, Vasculitis, MS)
- Down and Out pupil
- Normal pupil size (pupil sparing)
Surgical CN3 palsy
- Causes
- PICA aneurysm (para NS fibres on outside affected first),
- Tumour
- Cavernous sinus thrombosis (3, 4, V1, V2, 6)
- Down and Out pupil
- Fixed, dilated pupil
Complete vs Partial CN3 palsy
Complete CN3 palsy
- Down and Out
- Ptosis
- Dilated pupil
Partial CN3 palsy
- Dilated pupil
CN4 nerve palsy
Cause? Sx?
Cause = Trauma (longest intracranial course), Ischaemic, MS, SOL
-
Vertical diplopia
- Bielchowsky +ve (worse when tilting to same side)
- Compensatory head tilt (to OPPOSITE head of lesion)
- Affected eye
- Deviates upwards and rotated outwards
- Unable to move down
- Unable to move to opposite direction in horizontal plane (R or L)
- Right 4th nerve palsy –> inability to look Down and Left
CN6 palsy
Cause? Sx?
Cause = rasied ICP (nerve is anchored so prone to stretch)
-
Horizontal diplopia
- Worse on abduction to affected side
e.g. R sided CN6 palsy
Look Left
- Left lateral rectus + Right medial rectus working
- Both eyes look in same direction ∴ no double vision
Look Right
- Left medial rectus working (looks left)
- Right lateral rectus NOT working (unable to abduct)
- Eyes looking in different directions –> double vision
Internuclear ophthalmoplegia - Cause, Sx
Cause = MS ==> affecting Medial Longitudinal Fasciculus
- Horizontal diplopia
- Failure of adduction of ipsilateral (affected) eye
- Abducting nystagmus of contralateral (normal) eye
Painful, red eye
↓ visual acuity
Photophobia
Hypopyon
Diagnosis? Ix?
Keratitis (infection of cornea)
Ix: Corneal scrapping –> MC&S
Acute onset, unilateral, swelling of conjunctiva and eyelids
Periorbital oedema
Pain/Tenderness around eye
Fever
Diagnosis? Ix? Tx?
Periorbital cellulitis
Ix: CT (Sinus, Orbit) with contrast
IV Antibiotics
+/- Incision and Drainage of Abscess
Painful red eye
Photophobia
Synechiae
Flare
Ciliary flush
Hypopyon
Keratic precipiates
Diagnosis?
Anterior uveitis
Painless ↓ vision acuity
Floaters
Changes in colour vision
Retinal exudates and haemorrhages
NO PAIN
Diagnosis?
Posterior uveitis
Bacterial and Viral conjunctivitis
Most common causes
Presentation
Tx
Bacterial conjunctivitis (Neisseria gonorrhoea, Chlamydia)
-
Purulent discharge
- Unilateral
- Eyelids stuck together in morning
Viral conjunctivitis (adenovirus)
- Watery discharge
- Bilateral (highly infectious)
- Eyelids stuck together in morning
Tx
- Artificial tears
- Bacterial
- Topical Abx
- Viral
- Topical anti-histamines
- +/- Topical corticosteroids
- +/- Topical ganciclovir
