Term
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Definition
| group of ocular disorders involving optic neuropathy characterized by changes in the optic disk, and a loss of visual sensitivity and field |
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Term
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Definition
outer layer of eyeball;
thin, tough, leathery protective sheath |
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Definition
anterior section of shell;
clear tissue through which light rays enter eye |
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Definition
mucuous membrane lining back of eyelids;
functions to protect the eye |
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Definition
colored portion of eye that separates anterior & posterior chambers;
muscular activity controls size of pupil, regulating amount of light entering eye |
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Definition
blackened area in center of iris;
dilates or constricts depending on amount of light present |
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Definition
| increased light causes pupillary constriction |
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Term
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Definition
| decreased light causes pupillary dilation |
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Definition
behind the iris;
adjusts shape & density to focus light image on retina |
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Definition
posterior section of eye;
receives light through pupil and delivers image to brain via optic nerve |
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Definition
anterior & posterior chambers are filled with aqueous humor;
vitreous cavity (interior) is filled with vitreous fluid |
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Term
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Definition
clear, watery fluid formed in ciliary body that nourishes cornea & lens w/ O2 and vital nutrients;
provides necessary intraocular pressure to maintain shape of the eye;
outflow occurs through trabecular meshwork |
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Term
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Definition
majority of aqueous humor in anterior chamber leaves eye by this route;
outflow occurs through this to Schlemm's canal (conventional outflow) |
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Definition
| small, spongy tissue serving as pressure dependent "drainage site" of eye situated in angle where iris & cornea meet |
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Definition
aqueous humor in anterior chamber can also leave eye by this route;
it flows through ciliary body & suprachoroidal space (unconventional outflow) |
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Definition
| etiology is unknown; increased intraocular pressure (IOP) is not sole cause of damage: optic nerve ischemia, reduced blood flow to retina, excitotoxicity, autoimmune rxns |
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Term
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Definition
mechanical blockage of trabecular meshwork;
partial & complete blockage occurs intermittently |
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Term
| Risk Factors for Glaucoma |
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Definition
increased age;
family history;
Race: African or Hispanic Americans, Asian Americans & Inuit;
Disease states: DM, HTN, myopia, chronci corticosteroid use, elevated IOP |
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Term
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Definition
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Term
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Definition
| occurs as a complication of a variety of other conditions, such as injury, inflammation, vascular dx, and DM |
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Term
| Primary Open-Angle Glaucoma (POAG) |
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Definition
chronic, slowly progressing disease;
pts >50 yrs old;
bilateral dx;
most common version of dx;
Signs: disk changes, visual field loss, IOP is normal or elevated (>21 mmHg); |
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Term
| Primary Closed-Angle Glaucoma (CAG) |
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Definition
associated w/ symptomatic acute episodes;
results from mechanical blockage, produced from a narrow angle between cornea & iris or tight contact between iris & lens;
Signs: IOP is intermittently very high (>40 mmHg), cloudy cornea, blockage of aqueous fluid;
Symptoms: blurred vision, halos around lights, HAs, ocular pain or discomfort, N/V, abdominal pain, diaphoresis |
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Term
| Drug-Induced (Secondary) Glaucoma |
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Definition
Anticholinergic meds: increases IOP, angle closure --> TCAs, antihistamines, atropine;
polarizing neuromuscular blockers: increase IOP --> succinylcholine;
Topical, Inhaled, and Systemic Corticosteroids: reduces aqueous humor outflow, increase IOP --> prednisone, betamethasone |
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Term
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Definition
10-20 mmHg;
determined by relative production & elimination of aqueous humor |
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Term
| Factors that increase IOP |
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Definition
increased BP;
increased HR;
coughing;
neck compression |
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Term
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Definition
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Term
| Damaged Cup to Disk Ratio |
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Definition
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Term
| Visual Changes in Glaucoma |
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Definition
| loss of visual field & color vision |
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Term
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Definition
used to measure IOP;
GOLD STANDARD --> most accurate;
Eye is anesthetized & pt sits at slit lamp & a plastic prism is lightly pressed against eye to measure IOP |
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Term
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Definition
used to measure IOP;
puff of air is sent onto cornea to measure IOP; no direct contact;
used most often clinically |
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Term
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Definition
used to visualize optic nerve;
color & appearance of optic nerve is examined by looking directly through pupil |
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Term
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Definition
| microscopic exam of anterior chamber of eye to classify open-angle vs closed-angle glaucoma |
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Term
| Visual Field Examination (Perimetry) |
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Definition
| determines extent of damage to optic nerve & loss of visual field |
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Term
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Definition
decrease elevated IOP;
prevent further visual loss |
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Term
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Definition
| rapid reduction of IOP to preserve vision |
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Term
| Pharm agents that suppress aqueous production |
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Definition
topical beta-blockers (timolol, levobunolol, betaxolol, carteolol, metipranolol);
alpha-2 adrenergic agonists (brimonidine, apraclonidine);
carbonic anhydrase inhibitors (dorzolamide, brinzolamide, acetazolamide) |
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Term
| Pharm agents that facilitate aqueous outflow |
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Definition
miotics/parasympathomimetics (pilocarpine, carbachol);
sympathomimetics (epinephrine, phenylephrine, hydroxyamphetamine);
prostaglandin F2-alpha analogs (latanoprost, travoprost, bimatoprost) |
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Term
| Topical Beta-Blockers - timolol (Timoptic, XE), levobunolol (Betagan), betaxolol (Betoptic-S), carteolol (Ocupress), metipranolol (OptiPranolol) |
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Definition
MoA: blocks beta-receptors in ciliary epithelium, decreasing aqueous humor production;
1st line agent;
Decreases IOP by 20-30%;
Side Effects:
Local - dry eyes, transient burning/stinging, blurred vision;
Systemic: bradycardia, hypotension, negative inotropy, bronchospasm, CNS effects, alteration of serum lipids, blocks symtoms of hypoglycemia;
Relative C/Is: asthma, sinus bradycardia, 2nd-3rd AV block, atherosclerosis, DM, myasthenia gravis, oral beta-blockers; |
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Term
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Definition
| topical beta-blocker that lowers IOP less than timolol or levobunolol |
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Term
| Alpha-2 Adrenergic Agonists - bromnidine (Alphagan P), apraclonidine (Iodipine) |
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Definition
MoA: stimulates alpha-2 receptors to decrease aqueous humor production, increases uveoscleral outflow;
Alternative to beta-blockers as 1st line or adjunctive therapy;
Reduce IOP by 18-27% (2-5 hrs), 10% (8-12 hrs);
Side Effects:
Local - ALLERGIC rxns (lid edema, eye discomfort, foreign object sensations, itching, hyperemia;
Systemic - dizziness, somnolence, dry mouth, slight decrease in BP/pulse, fatigue;
Relative C/Is: CVD, cerebrovascular dx, renal compromise, DM, pts on antihypertensives, MOA-Is, TCAs;
Shorter duration of action --> BID-TID dosing;
Nasolacrimal occlusion improves response & allows for q12 hr dosing;
Do NOT use in infants!!! |
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Term
| Carbonic Anhydrous Inhibitors - dorzolomide (Trusopt), brinzolamide (Azopt), acetazolamide (Diamox), methazolamide |
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Definition
MoA: decrease ciliary body aqueous humor secretion by blocking active secretion of Na & HCO3 ions;
Topical: Alternative 1st line or adjunctive therapy;
Oral: 3rd line agents;
Reduces IOP 15-26% (topical), 25-40% (oral);
Side Effects:
Local - transient burning/stinging/blurred vision, tearing, ocular discomfort;
Systemic: rare;
Relative C/Is: SULFA allergy, sickle cell dx, respiratory acidosis, pulmonary disorders, renal calculi, electrolyte imbalance, kidney or liver impairment, DM, Addison's dx;
Avoid/caution in pts w/ sulfa allergy;
Do NOT use oral & topical in combo;
Oral agent are poorly tolerated; |
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Term
| Miotics/Parasympathomimetics - pilocarpine, carbachol |
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Definition
MoA: increase aqueous outflow by physically pulling open trabecular meshwork 2ndary to ciliary muscle contraction, reduces resistance to outflow & reduces IOP;
P: 3rd line agent;
C: last line agent;
Reduces IOP by 20-30%;
SIDE EFFECTS:
Local - miosis (decreases night vision), frontal HAs, periorbital pain, brow aches, eyelid twitching, conjunctival irritation;
Systemic - diaphoresis, N/V, diarrhea, cramping, urinary frequency, bronchospasm, heart block;
Relative Contraindications: cataracts;
Pts w/ darly pigmented eyes require higher conc. of P than pts w/ ligher pigmented eyes;
C is longer acting than P |
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Term
| Sympathomimetics - epinephrine, phenylephrine, hydroxyamphetamine |
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Definition
MoA: not fully understood;
3rd line agent for mild-moderate IOP elevation, 2nd line adjunctive therapy;
Reduces IOP by 20%;
Side Effects:
Local - tearing, burning, ocular pain, brow ache, blurred vision, deposition of pigment in conjunctiva & cornea;
Systemic: HA, increased BP, tachycardia, tremor, anxiety, increased perspiration, arrhythmias;
Relative C/Is: cardiovascular disorders, DM, hyperthyroidism, angle-closure glaucoma; |
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Term
| Prostaglandin F2-alpha analogs - latanoprost (Xalatan), travoprost (Travatan Z), bimatoprost (Lumigan) |
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Definition
MoA: reduces IOP by increasing uveoscleral outflow & trabecular outflow of aqueous humor;
1st line or alternative agent;
Reduces IOP by 25-35%;
Side Effects:
Local - corneal erosions, conjunctival hyperemia, altered iris/eyelid/skin pigmentation, transient burning & stinging, dry eyes, itching, hypertrichosis, increased eyelash pigmentation;
Systemic: migraine HAs;
Relative C/Is: pts w/ ocular inflammation issues;
Once daily administration at bedtime;
Can be used in combo w/ other antiglaucoma agents or as monotherapy; |
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Term
| Monitoring Parameters for Tx of Glaucoma |
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Definition
IOP: q2-4 wks initially, 4-6 wks after starting a med, q3-4 months when stable;
Visual Field Test & Visualization of Optic Disk: annually, earlier if unstable;
Safety/Adherence/Administration Technique (NLO): every visit |
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Term
| Non-pharmacological Therapy |
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Definition
Argon Laser Trabeculoplasty (ALT);
Iridectomy;
Surgical Trabeculectomy; |
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Term
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Definition
| beta-blockers or latanoprost (Xalatan) |
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Term
| Alternative 1st line agents for POAG |
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Definition
| bimatoprost, travoprost, brimonidine, topical CAIs |
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Term
| Second line agents for POAG |
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Definition
unoprostone;
apraclonidine |
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Term
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Definition
| oral CAIs, pilocarpine, dipivefrin |
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Term
| Last line agents fot Tx of POAG |
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Definition
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Term
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Definition
Pilocarpine 1-2% 1 gtt q5 min for 2-3 doses then q4-6 hrs;
Osmotic agents: oral glycerin 1-2 g/kg, if not tolerated, then IV mannitol 1-2 g/kg;
Secretory Inhibitors - beta-blockers, topical/oral CAIs, alpha-2 agonists, or prostaglandin F2-alpha analog |
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