Glaucoma Flashcards
What is the pathophysiology of glaucoma?
Eye condition that causes progressive degeneration of the optic nerve
- Loss of nerve tissue –> gradual, irreversible vision loss –> blindness
What are the 4 types of glaucoma we talked about?
- Primary Open-Angle Glaucoma
- Angle-Closure Glaucoma
- Secondary Glaucoma
- Normal-pressure glaucoma
What is secondary glaucoma?
Occurs as a result of an injury, infection, or tumor, in or around the eye that causes increased fluid pressure
What is normal-pressure glaucoma? (2)
Optic nerve becomes damaged despite normal eye
pressures
– Unclear why this happens ?sensitive optic nerve or
insufficient blood supply (e.g. atherosclerosis)
What is primary open-angle glaucoma? (3)
- Increased production or ↓ drainage of aqueous fluid within
the eye -> ↑ intraocular pressure -> damage to optic
nerve - Develops gradually and painlessly – in early stages,
can only be diagnosed by eye exam
– By the time vision is impaired, damage is irreversible - Accounts for > 90% of glaucoma cases
What are some risk factors for open-angle glaucoma? (11, no need to know all)
- Elevated intraocular pressure (> 21 mmHg in at least one eye)
– Only modifiable risk factor for glaucoma development and progression! - Older age
- Family history
- African descent
- Myopia
- Hypertension
- Diabetes
- Migraines
- Previous intraocular surgery
- Blunt or penetrating eye trauma
- Corticosteroids
– Systemic > ophthalmic > inhaled or intranasal
True or False? Angle-closure glaucoma is a medical emergency
True
What is angle-closure glaucoma?
Occurs when the iris bulges forward to block the drainage angle formed by the cornea and iris
- Aq fluid cannot drain –> acute, severe increased IOP –> optic nerve damage
How is angle-closure glaucoma treated? (2)
- Eye drops/oral medications acutely to lower intraocular pressure
- ASAP - laser surgery to widen the drainage angle
What are some signs and symptoms of angle-closure glaucoma? (5)
- Severe eye pain
- Eye redness
- Blurred vision, halos around lights
- Nausea and vomiting
- Headache
Refer to ER or ophthalmologist for urgent care!
What are some risk factors for angle-closure glaucoma? (7)
- Older age
- Female
- Positive personal or family history
- Asian or Inuit descent
- Hyperopia
- Proliferative diabetic retinopathy
- Topiramate use
Many anticholinergic medications carry warnings to avoid in individuals with “glaucoma.” Who does that really refer to?
Only important for patients with acute angle-closure glaucoma.
Not relevant with open-angle glaucoma OR those with surgically treated angle-closure glaucoma
What are the goals of therapy for glaucoma? (4)
- Prevent, halt or slow vision loss
- Preserve the structure and function of the
optic nerve - Improve or maintain functional vision
- [Acute angle closure: Eliminate pain and other
associated symptoms]
What are the (general) treatment options for open-angle glaucoma? (3)
- Eye drops
- Laser surgery
- Eye surgery
In open-angle glaucoma treatment, the target IOP is determined based on? (4)
- The extent of glaucomatous damage
- Amount of disc cupping
- Vision loss - The estimated IOPs associated with that damage
- The burden of therapy to achieve the desired IOP
- Target IOP further reduced if damage to optic disc or visual field progresses
List the groups of topical agents used to treat open-angle glaucoma (5)
- Prostaglandin analogues
- Beta-blockers
- Alpha-2 adrenergic agonists
- Carbonic anhydrase inhibitors
- Cholinergic agonists
List the topical prostaglandin analogues (3)
- Latanoprost
- Travoprost
- Bimatoprost
What is the MOA of prostaglandin analogues?
Prostaglandin F2-analgoues which increase aqueous humor outflow
What are the 2 groups of first-line topical meds to treat open-angle glaucoma?
- Prostaglandin analogues
- Beta-blockers
What are the 2 groups of second-line topical meds to treat open-angle glaucoma?
- Alpha-2 adrenergic agonist
- Carbonic anhydrase inhibitors
What is the last-line topical agent used to treat open-angle glaucoma
Cholinergic agonists
ADEs of topical prostaglandin analogues include? (3)
- Mild conjunctival hyperemia
- Thicker eyelashes
- Possible iris darkening (rare)
True or False? If one topical prostaglandin analogue is tried for open-angle glaucoma and it doesn’t work then it’s not worth trying agents from the same class?
False - if one is not effective or tolerated try another within this class
What are three topical beta-blockers used for POAG treatment
- Betaxolol
- Levobunolol
- Timolol
What is the MOA of topical beta-blockers for treatment of POAG?
Decreased production of aq humor
Topical beta-blockers should be avoided in patients with ________ or ___________
syncope; bradycardia
Topical beta-blockers should be used with caution in pts with?
Asthma/COPD
- Avoid in severe disease
- Monitor for worsening of these conditions
- Betaxolol is cardio (B1) selective
Name the topical alpha-2 adrenergic agonist drug
Brimonidine
What is the MOA of brimonidine?
Decreases production of aq humor and increases outflow
Alpha-2 adrenergic agonists are primary used as __________ therapy for POAG. Why?
adjunctive;
- Higher rate of conjunctival hyperemia and ocular allergy than prostaglandins or beta-blockers
Name the 2 topical carbonic anhydrase inhibitors
- Dorzolamide
- Brinzolamide
What is the MOA of topical carbonic anhydrase inhibitors?
Inhibition of carbonic anhydrase decreases production of aq humor.
Topical vs. Oral carbonic anhydrase inhibitors. Which is better at decreasing IOP?
Oral (but very poorly tolerated so not used much long-term)
Name the topical cholinergic agonist
Pilocarpine
What is the MOA of pilocarpine?
Stimulate muscarinic receptors –> constricts the ciliary muscle –> increases aq humor outflow
Pilocarpine tolerability is poor. What are the ADEs? (4)
- Miosis -> ↓ night vision
- Nearsightedness
- Ciliary spasm
- Rare: Retinal detachment
Combo products to lower IOP. Yay or nay
Yay.
Mostly gonna be timolol combined with something else
What are some notes about administration of eye drops (specifically for glaucoma ig)? (3)
- Topical glaucoma medications are highly
concentrated to ↑ intraocular penetration
– To ↓ systemic absorption, occlude the nasolacrimal
drainage system or close eyes for 1-3 minutes after
instilling drops - Allow 5 minutes between administering different
types of eye drops - Wait 15 minutes after instilling eye drops before
applying contact lenses
____________ ________ is the most common preservative in eye drops
Benzalkonium chloride
Up to 6% of people are allergic to benzalkonium chloride preservatives. What alternatives are there for those people? (2)
- Alternative preservatives
- Available for travaprost and brimonidine - Some drops are available in preservative-free, single dose units
Describe the role of the pharmacist in glaucoma management (4)
- Proper eye drop administration technique
– Encourage discarding eye drops as recommended - Assess tolerability
- Adherence!!
- Encourage regular follow-ups with eye care
professional
