glaucoma clinical Flashcards
what is glaucoma
- Irreversible, progressive disease of the optic nerve, if left untreated, will progress to tunnel vision and blindness
how does glaucoma progress
○ Blurring at peripheral parts of the eye
○ Dims and constricts outer vision
○ Eventually peripheral vision disappears
what is the optic nerve
- Made up of cells in the retina - carrying information to the brain from the retina
- Ciliary body produces aqueous fluid and passes over the eye before leaving in one or two ways
what is the optic nerve head
○ Where the optic nerve (and blood vessels) exits the eye via the laminar cribosa
○ Blind spot
what are the 3 types of glaucoma
congenital vs acquired
primary vs secondary
open vs closed angle
what is primary angle closure glaucoma
○ Classically affects small hypermetropic eyes - long sighted
○ Irido-corneal angle occlusion
what are the symptoms of acute primary closed angle glaucoma
§ Pupil block
§ Painful red eye
§ Blurred vision
§ N&V due to pain
§ Mid-dilated pupil
§ Cloudy cornea
§ Shallow anterior chamber
§ Elevated intra-ocular pressure
§ Closed angle at gonioscopy
§ Glaukomflecken
§ Possible cataract
how is primary angle closure treated - acute an chronic
laser iridotomy
cataract surgery
medicine to lower IOP
which classes of drugs can induce primary angle closure glaucoma
topical mydriatic drugs
nebulised drugs
oral/iv drugs
which topical mydriatic drugs can induce primary angle closure glaucoma
Tropicamide, cyclopentolate, phenylephrine, atropine
which nebulised drugs can cause primary angle closure glaucoma
Ipratropium, salbutamol, ephedrine
which oral/IV drugs can cause primary angle closure glaucoma
TCAs
SSRIs
anticholinergic - oxybutynin/atropine
which other drugs can cause primary angle closure glaucoma
§ Topiramate
§ Hydrochlorothiazide
§ Acetazolamide
§ Quinine
§ Tetracyclines
§ Pilocarpine
OTC flu remedies
what is primary open angle glaucoma
- Most common type in the UK
- Initially asymptomatic
Usually slow and progressive
- Initially asymptomatic
what are the causes of POAG
- Not understood
- Raised IOP
- Mechanical
- Movement of laminar cribosa causing damage
- Ischaemic
- At optic nerve head
what are the risk factors for POAG
- IOP
- Age
- Genetics
- Family history
- Myopia - short sightedness
- Type of optic nerve head
- Vascular or haematological
- Neurogenic
what screening options are there for POAG
- Optic nerve imaging
- Visual field testing
- Risk factor assessment
- IOP
- Family history
- Other risk factors
- Slit-lamp examination and gonioscopy
what are the treatment options for POAG
- Various drops can be used
○ Reduce aqueous production
○ Increased outflow of aqueous- Laser
○ Selective laser trabeculoplasty improves drainage
○ Cyclodiode laser therapy reduces aqueous production
§ Last resort - Surgery
○ Lots of options
○ Trabeculectomy is gold standard
- Laser
what are prostaglandin analogues
- Latanoprost, Travoprost, Bimatoprost
OD ON - increase uveoscleral road
s/e of prostaglandin analogues
- Systemic s/e are rare
- Ocular s/e
- Lash growth
- Iris pigmentation
- Periocular skin darkening
- Conjunctivitis
- Post-op cystoid macular oedema
what beta blockers are used for glaucoma
- Non-selective and cardio selective available
- Timolol
- Reduce aqueous production
- BD or OD (if OD mane best)
s/e of beta blockers used for glaucoma
- Breathlessness
- Bradycardia
- Tiredness
- Depression
- Erectile dysfunction
- Hypotension
- Angina
how are carbonic anhydrase inhibitors used for glaucoma
- Reduced perfusion of aqueous
- Least potent - TDS
- C/I in sulfonamide sensitivity
- Brinzolamide and dorzolamide
which 3 alpha agonists are used in glaucoma
- brimonidine
- High allergy rate
- Taste perversion
- CNS s/e - nightmares
- Apraclonidine
- Short term - pre surgery
- Avoid MAOIs or TCAs
