Opthalmology Flashcards
Glaucoma vs Uveitis for Acute Painful Red Eye
How to differentiate ?
Glaucoma -
Dilated, Haloes
Uveitis -
Constricted Oval Pupil
Horners Syndrome
- Central Lesions
- Pre-Ganglionic
- Post-Ganglionic
- Anhydrosis of Face Arms Trunk
Stroke
Syringomyelia
Multiple sclerosis
Tumour
Encephalitis
- Anhydrosis of Face
Pancoast Tumour
Thyroidectomy
Trauma
- Post Ganglionic - No Anhydrosis
Carotid artery dissection
Carotid aneurysm
Cavernous sinus thrombosis
Cluster headache
What drug is used for Dilating Pupils in Horner’s Syndrome ?
Apraclonidine drops (an alpha-adrenergic agonist)
causes pupillary dilation in Horner’s syndrome due to denervation supersensitivity but produces mild pupillary constriction in the normal pupil by down-regulating the norepinephrine release at the synaptic cleft
Keith-Wagener’s Classification
Grade 1 – Silver wiring
Grade 2 – + AV nicking
Grade 3 – + flamed shape, dot and blot haemorrhages and cotton wool exudates
Grade 4 – + papilloedema
How to differentiate 1st/2nd order from 3rd order in Horner’s Syndrome ?
Apraclonidine drops 1st which will cause ipsilateral dilation and contralateral constriction = Confirming Horner
Then Hydroxyamphetamine drops will dilate pupils for 1st/2nd order
Glaucoma Pharmacology !!!
Watch Medicosis Video if needed
Alpha 1 Agonist –> Vasoconstriction so less Plasma filtered to make Aqueous Humor
Beta Blocker —> Prevent formation of Aqueous Humor by Panacinar Cells
OR Alpha 2 (Anti-sympathetic) which causes Less Noradrenaline release which will inturn not stimulate Beta Receptors so technically Beta Blockade
Alpha 2 agonist (Primary MOA)
OR PGF2 alpha (-prost) —> Dilate the Eye and Increase the Angle
Carbonic Anhydrase acts on PCT reduced water absorption and reduce plasma formation
Parasympathomimetic (Pilocarpine) which is a Muscarinic Agonist (M3) –> Increases the Angle and Promotes Drainage
- Any inhibitor / blocker –> reduce production
- Any agonist
–> Increase outflow
Brimonidine (alpha 2 agonist) does both
Side Effects of Prostaglandin Analogues
Long Eye Lashes
Brown Iris Pigmentation
When not to give Alpha 2 Agonist ?
MOAI and TCA co-use
Diabetic Retinopathy Classification
NPDR
PDR
Maculopathy
- Mild NPDR
1 or more microaneurysm
- Moderate NPDR
microaneurysms
blot hemorrhages
hard exudates
cotton wool spots (‘soft exudates’ - represent areas of retinal infarction)
venous beading/looping
intraretinal microvascular abnormalities (IRMA) less severe than in severe NPDR
- Severe NPDR
blot haemorrhages and microaneurysms in 4 quadrants
venous beading in at least 2 quadrants
IRMA in at least 1 quadrant
- PDR
Neovascularization
Common in T1 DM
- Maculopathy
Macular oedema
Common in T2 DM
Treatment for NPDR PDR and Maculopathy
PDR
Neovascularization - Laser photocoagulation
a. 50% experience reduction in Peripheral Vision
b. Decrease in NIGHT VISION)
Maculopathy
intravitreal VEGF inhibitors
Drugs that Precipitate Glaucoma
Anti-Cholinergic and TCA
Flashes in Which Conditions ?
Flashes in
Vitreous detachment (Flashes often on Temporal Side & Diabetics) + Weiss Ring
Retinal detachment (Peripheral to Central Shutdown)
Cataract
Holmes-Adie pupil
Dilated
Absent Knee Reflexes
Absent Eye Reflex
Marcus Gunn Pupil-Relative afferent pupillary defect-
defect is found by the ‘swinging light test’. It is caused by a lesion anterior to the optic chiasm i.e. optic nerve or retina, lesion btw optic chiasma & LGB is congruous defect and lesion posterior to LGB & occipital area is incongruous defect.
Finding: the affected and normal eye appears to dilated rather constricting when light is throw on the affected & constrict when light throw into the healthy eye.
Causes: retina: detachment, optic nerve: optic neuritis e.g. MS
Pathway of pupillary light reflex:
afferent: retina → optic nerve → lateral geniculate body(LGB) → midbrain
efferent: Edinger-Westphal nucleus (midbrain) → oculomotor nerve
Does Viral URTI associate with Blepharitis ?
Nope !!!
Pupils Dilated in which conditions ?
HoT COP ATTACK with a GUN
Holmes Adie
Traumatic Iridoplegia
Congenital
Oculomotor nerve palsy
Pheochromocytoma
Atropine
Tropicamide
TCA
Amphetamine
Cocaine
Marcus gun/RAPD
Dacryocystitis Treatment
Systemic Abx –> IV if Periorbital Cellulitis
Pinguecula ?
What does it Progress into ?
Benign yellow-white thickening which is usually bilateral and caused by ultraviolet (UV) exposure.
Progresses into Pterygium Surfers Eye - raised, fleshy, triangular-shaped growth that starts in the corner of your eye
What’s a Chalazion ?
Meibomian cyst - Painless
Most Common Ocular Manifestation in RA ?
Keratoconjunctivitis Sicca
Herpes Simplex Keratitis Investigation ?
Fluorescein Staining –> Dendritic Ulcers
1st line for Chronic Open Angle Glaucoma ?
Lantanoprost
Prostaglandin Analogues !!!!!!!
vs Open Angle if Acute
IV Carbonic Anhydrase and Timolol
Treatment of ARMD ?
Investigations ?
If Dry - Watch and Wait
If Wet - Anti VEGF
Slit Lamp is the Investigation of Choice +/- Colour fundus photography
Once Wet ARMD suspected –> fluorescein angiography +/- indocyanine green angiography
Optical coherence tomography - To show 3D Retina
Hypermetria or Myopia
Risk Factor for Acute vs Chronic Open Angle Glaucoma ?
Acute - Asians / Hypermetria / Anti Cholinergic or Antidepressants / 55-70
Chronic - Africans / Myopia / >40
Strongest Risk Factor for ARMD ?
Smoking !!!
Retinitis Pigmentosa
Night Blindness + Tunnel Vision
Fundoscopy - black bone spicule-shaped pigmentation in the peripheral retina, mottling of the retinal pigment epithelium
Associated diseases
Refsum disease: cerebellar ataxia, peripheral neuropathy, deafness, ichthyosis
Usher syndrome
abetalipoproteinemia
Lawrence-Moon-Biedl syndrome
Kearns-Sayre syndrome
Alport’s syndrome
Optic Neuritis
- Features
- Investigation of Choice
- Treatment
Red Saturation + Central Scotoma + Ophthalmoplegia + RAPD
NO VISION LOSS !!!!!
MRI with Gadolinium Contrast
Steroids
What pathologies cause Tunnel Vision (CHOP P GR)
Choroidoretinitis
Hysteria
Optic Atrophy 2ry to tabes dorsalis
Papilloedema
Glaucoma
Retinitis pigmentosa
Pathologies about Angloid Retinal Streaks
SPACE
sickle-cell anaemia
Paget’s disease
pseudoxanthoma elasticum
acromegaly
calcification and breaks in Bruch’s membrane
Ehler-Danlos syndrome
CRVO vs CRAO Fundocopy Changes
CRVO - Stormy Sunset - Multiple Hemorrhages
CRAO - Cherry Red Spot
Orbital Cellulitis Tx
- IV antibiotics –> risk of cavernous sinus thrombosis and intracranial spread
Orbital Cellulitis Risk Factors
Risk Factor
- Lack of Hemophilus influenzae type b (Hib) vaccination
Preseptal vs Orbital Cellulitis
Reduced visual acuity, proptosis, ophthalmoplegia/pain with eye movements
in Orbital Cellulitis
Angloid Retinal Streaks on Fundoscopy
Irregular dark red lines radiating from the optic nerve.
Vitamin AC and E are given in ARMD.
So when is it contraindicated to give this ?
In SMOKERS but its not ACE its only Beta-Carotene
Herpes Zoster Opthamicus
- Treatment
- Predictor of Ocular Involvement
- Oral Acyclovir
- Hutchinson’s Sign
Optic Atrophy
Acquired
MS
papilloedema (longstanding)
raised intraocular pressure (e.g. glaucoma, tumour)
retinal damage (e.g. choroiditis, retinitis pigmentosa)
ischaemia
toxins: tobacco amblyopia, quinine, methanol, arsenic, lead
nutritional: vitamin B1, B2, B6 and B12 deficiency
Congenital causes
Friedreich’s ataxia
mitochondrial disorders e.g. Leber’s optic atrophy
DIDMOAD - the association of cranial Diabetes Insipidus, Diabetes Mellitus, Optic Atrophy and Deafness (also known as Wolfram’s syndrome)
