Anterior Chamber Disorders Flashcards
What device do we use to help diagnose glaucoma?
tonopens
Types of glaucoma?
3
- Open-angle glaucoma
- Angle-closure glaucoma (sudden closure)
- Acute angle-closure glaucoma
What is happening in open angle glaucoma?
Optic neuropathy results in progressive loss of retinal ganglion cell axons
-first lose your visual fields then central vision as it progresses to blindness
Risk factors for open angle glaucoma?
7
- Age: 1%
What is being damaged in glaucoma?
What causes this damage?
slow progressive damage to the optic nerve
Increased internal ocular pressure
Symtpoms of primary open angle glaucoma?
symptoms are rarely experienced until central vision is affected. Once vision is lost it cannot be recovered
How do we diagnose primary open angle glaucoma?
funduscopic exam and visual acuity with the presence of elevated intraocular pressure
What in a funduscopic exam would indicate open angle glaucoma?
presence of cupping
–A cup that is greater than 50 percent of the vertical disc diameter is a useful threshold for suspicion of glaucoma.
What is the cup and what is the disc?
the cup is the optic nerve and the disc is the impression made by the nerves
Whats the normal cup to disc ratio?
1/3
How does glaucoma affect the cup size?
What will the rim of the nerve on the temporal side tell us?
makes it larger in a vertical oval type pattern
If it is very thin or sloped it will be more likely to have glaucoma
What is primary angle closure glaucoma characterized by?
What does this cause?
by narrowing or closure of the anterior chamber angle
This narrows or closes the normal drainage pathway of the aqueous humor which then builds up leading to elevated IOP
= damage of optic nerve
Risk factors for primary angle closure glaucoma?
6
- Family history
- Age older than 40 or 50 years
- Female
- Hyperopia (farsightedness)
- Medications—decongestants, antipsychotics, antidepressants
- Race—Inuit and Asian populations
Pathophysiology of chronic glaucoma?
3
- abnormal internal pressure resulting from aqueous fluid blockage
- clogged trabecular meshwork leading to drainage canal
- optic nerve endings slowly deteriorate under abnormal pressure
Symptoms of chronic glaucoma?
usually asymptomatic
How would we diagnose chronic glaucoma?
5
- Glaucomatous optic nerve damage (thinning, cupping or notching of the disc rim)
- AND the presence of characteristic abnormalities in the visual field in the absence of other causes for a field defect
- Adult onset
- Open, normal appearing anterior chamber angles
- Absence of known (secondary) causes of glaucoma
Do all patients with open angle glaucoma have elevated IOP?
no. most do but some don’t
A IOP of what would make us call an emergency referral?
over 40mmHg
An IOP of what would make us call an urgent referral?
And what is the time frame for an urgent referral?
30-40 mmHg
Within 24 hrs, if no symtpoms suggesting acute glaucoma
If pressure is at 25-29mmHg what would we do?
evaulate again in a week
If pressure is t 23-24mmHg what should we do?
repeat the measurement to confirm and or referral for a comprehensive eye exam
Whats a normal IOP?
12-20mmHg
The American Academy of Ophtho recommends screening for glaucoma as part of the comprehesive adult eye exam. What procedures does this include? 3
- measuring IOP,
2. evaluating the optic nerve and 3. testing for visual field defects
When should we be tested for glaucoma wihout any risk factors from ages 40-60?
With risk factors?
every 3-5 years
1-2 years
What are the three types of treatment options for glaucoma
medications (eyedrops)
laser surgery
incisional surgery
What procedures would help with drainage in patients with glaucoma?
3
Argon laser trabeculoplasty (ALT) Improves drainage of fluid out of the eye Trabeculectomy (75% success rate) can be repeated up to 3 times or more Drainage implant tubes
Acute angle- closure glaucoma occurs only with what?
with closure of a preexisting narrow anterior chamber angle
Predisposing factors for acute angle-closure glaucoma?
4
Elderly
Hyperopes
Inuits
Asians
What can acute angle closure glaucoma be precipitated by?
pupillary dilation
- -sitting in a dark theater and having the lights from the screen flash on abruptly
- -times of stress
- -pharmcological mydriasis
What drugs could cause acute angle closure glaucoma?
two categories of meds
five specific examples
- Anticholinergics or
- sympathomimetics
Nebulized bronchodilators, atropine as pre-op medication, antidepressants,
nasal decongestants,
tocolytics.
Secondary acute angle glaucoma may be observed with what issues?
2
anterior uveitis
dislocation of the lens
Symptoms of acute closed angle glaucoma?
5
- Rapid onset
- Severe eye pain and HA
- Profound visual loss with “halos around lights”
- May have photophobia
- Nausea and vomiting
***These patients are in distress, usually covering their eye or clutching their frontal region. Often the headache is accompanied with nausea and vomiting.
Signs of acute closed angle glaucoma?
4
- Conjunctival redness (red eye)
- Cornea edema or cloudiness
- Shallow anterior chamber
- Mid-dilated pupil that reacts poorly to light
Pathphysiology behind acute angle glaucoma?
3
- obstructed trabecular network
- the angle b/w the iris and the cornea narrows or closes
- Iris pushes forward towards the cornea
How serious is acute angle closure glaucoma?
Angle closure glaucoma is an emergency!!
Treatment for acute closed angle glaucoma for primary care?
Emergent referral to an ophthalmologist
If it will be greater than 1 hour before the patient can be seen than start treatment: 2 250 mg tablets of acetazolamide (can also be given IV—can use mannitol , glyercol or isosorbide IV)
How does acetazolamide work?
Decreases the pressure in the eye and used with other medicines to reduce edema (excess water retention).
- carbonic anhydrase inhibitor
- decreases secretion of aqueous humor
What is the definitive therapy for acute closed angle glaucoma?
laser or surgical peripheral iridotomy in both eyes
Once we get them to the Ophthalmologist what is the treatment? (for acute clsoed angle glaucoma)
3
One regimen: 1 drop of each, one minute apart:
0.5% timolol (Timoptic)
1% apraclonidine (lopidine)
2% pilocarpine (Isopto, Carpine)
What is the prognosis for acute closed angle glaucoma?
Good if treated; severe and permanent vision loss if untreated in 3-5 days
What is intraocular inflammation called?
Uveitis
What are the causes for Uveitis and what is the most common?
immunilogic is most common but can be infection
Nongranulomatous anterior uveitis is most often associated with what kind of conditions?
HLA-B27
What are HLA-B27 conditions?
6
- Ankylosing spondylitis (bamboo spin- pulls everything tight and together)
- Reactive arthritis (writer’s syndrome) Cant see, cant pee, cant climb a tree(swollen joint) and dont sleep with me-they get blurring vision
- Psoriasis
- Ulcerative colitis
- Crohn’s disease
- Behçet’s syndrome causes anterior uveitis with recurrent hypopyon, no pain, and posterior uveitis with branch retinal vein occlusions (presents as herpes) inital presenation uveitis
Whats another name for uveitis?
iritis
What is often the inital presentation of HLA-B27 diseases?
uveitis
What does uveitis look and feel like?
2
bright red aorund iris/ciliary flush
pain of about 8/10
Infectious etiologies of uveitis?
5
CMV Toxoplasmosis Syphilis Cat Scratch disease HSV and HZV
Syphilis can present as uveitis and what two other eye ailments?
chorioretinitis or retinal vasculitis
What is cat scratch disease associated with?
optic nerve edema
HSV and HZV causes what kind of uveitis?
cause keratouveitis: an inflammation of the cornea w/ uveitis
Whats the pathophysiology behind keratouveitis caused by HSV and HZV?
3
- Caused vesicles on the cornea and reduces sensation
- Can elevate IOP
- May also cause acute retinal necrosis
Symptoms of anterior uveitis or iritis?
eye pain
redness
may have visual loss
What kind of uveitis is the most common?
anterior. 4 times more common
Signs and symptoms of posterior uveitis?
6
- Cells seen in the vitreous
- Inflammatory lesions may be seen on retina or choroid
- Fresh lesions are yellow while older lesions are pigmented
- Usually presents with gradual vision loss
- Bilateral involvement is common
- Usually painless unless anterior involvement
How do we treat uveitis due to infection?
3
Antiviral agent + topical glucocorticoids
Appropriate antibiotics for bacterial infections
How do we treat noninfectious uveitis?
anterior 2 and posterior 2 treat differently
Anterior—topical glucocorticoids + dilating drop (scopalamine or cyclopentolate)
Posterior—periocular injection of triamcinolone and if resistant inflammation systemic corticosteroids
pupil will often times be mishapen/pretty terrible pain
What symptom is associated with CMV?
owl eye
What can you do in primary care with uveitis?
After discussion with the ophthalmologist initiate cycloplegic agent such as topicamide or cyclopentolate to help relieve pain and help prevent synechiae AVOID atropine (effects persist too long)
Complications associated with uveitis?
6
Cataracts Calcifications in the cornea Glaucoma Uveitis Permanent vision imipairment Blindness
Whats synechiae?
adhesion of the iris to the lens
or cornea
What parts of the eye does anterior uveitis include? 2
ciliary body and iris
What parts of the eye does intermediate uveitis include? 2
vitreous and peripheral retina
What parts of the eye does posterior uveitis include?
choroid and possibly the retina, optic nerve
What is the leadng cause of blindness in the world?
cataracts
What are the benfits for surgery for cataracts?
3
- Improves quality of life of older adults
- Studies have shown older adults who have had cataract surgery have fewer falls & broken hips
- Studies have also shown older adults who have had cataract surgery have fewer MVA
Whats the pathophysiology behind cataracts?
3
- Lifelong growth of the lens produces stratified epithelia with a high content of cytoplasmic protein
- The lens does not shed these epithelial cells and with age they can become opaque
- Experimental evidence suggests photo-oxidative insult potentiated by toxic or sensitizing substances
What is cataracts?
Opacity of the lens of the eye that causes partial or total blindness.
Causes of cataracts?
11
Genetic predisposition/FHx
Age
Smoking (20% of the cataracts in U.S. caused by smoking)
Sunlight exposure
Steroids (including long term use of inhaled corticosteroids)
Diabetes mellitus
Metabolic syndrome
Trauma
Alcohol consumption
Low education
Poor lifestyle habits—including malnutrition & physical inactivity
Presentation of cataracts?
4
- Painless,
- progressive cataract formation that is typically
- bilateral and may be
- asymmetric
Patients complain of what with cataracts?
3
Problems w/ night driving
Reading road signs
Difficulty reading fine print
What will you see on the optic exam in these patients?
3
Darkening of the red reflex
Difficulty visualizing the retina
Frank opacity of the lens
When is catarct surgery done?
when it interferes with the patients quiality of life
or in rare cases when its causing glaucoma
How is the patient sedated in cataract surgery?
IV sedation with local anesthetic
What is the patient put on after cataract surgery?
Patient is put on glucocorticoid and NSAID topical eyedrops after surgery
How long is the eye patched for after cataract surgery?
24 hours
When is the follow up appointments for cataract surgery?
1 day, 1 week, 1 month
Is cataracts an emergent referral?
nope
Describe the process of cataract surgery?
phacoemulsification
- use ultrasound and vacuum to remove lens
- lens implant (plastic or silacone)
When is the second eye done after the first eye in cataract surgery?
1-2 week after