Eye Flashcards
Flow of Aqueous Humor
Ciliary body->Post Chamber->Ant Chamber->Canal of Schlemm
Sensory Innervation of the Eyes
CN II, II, IV, VI
Blepharitis
-Inflammation of the eyelid (Meibomian gland)
-Leads to: excess tears, flaking, crusting, redness
-Most often occurs in people with rosacea, seborrheic dermatitis…
A patient with blepharitis often awakens with:
Crusty, dried mucus in the corner of their eyes
Treatment of blepharitis
Moisten a washcloth or cotton-tipped applicator and gently clean lids and lashes
Ectropion
Lower eyelid turns outward, and doesn’t completely touch/cover the eye
-Mostly in the elderly or secondary to scars
Ectropion treatment
If mild, artificial tears or lubricating ointment will work
-If worse, surgery to reposition lower eyelid
Entropion
Eyelid and eyelashed turn inward towards eye, causing the lashes to rub against cornea and conjunctiva
Entropion treatment
Soothing eyedrops/artificial tears
-Tape applied to eyelid to pull it down towards the cheek underneath
-Surgery to tighten up the lid
Stye
Painful, tender, red, pus-filled infection of the glands
-Often secondary to blepharitis
-Looks like a pimple or boil pointing on lid margin
Stye Treatment
Don’t squeeze the stye
-As soon as the stye begins to form, apply clean, warm washcloth compress several times/day until the stye opens
Chalazion
Swelling in the eyelid caused by blockage of one of the glands that lubricate the eye
-Larger and less painful than styes
Chalazion: Treatment
Small ones go away on their own
-Can speed up process by applying warm water compress 2-4x/day for 5-20 minutes
-If large, or it fails to go away: antibiotics
Xanthelasmas
Slightly raised, yellowish, well-circumscribed plaques on the nasal portion of both eyelids
-May accompany lipid disorders as well as diabetes and obesity
-No Treatment necessary
Xanthelasma Treatment
None, unless for cosmetic reasons through surgery
Papillomas and Cysts
-Papillomas: Slow-growing, fleshy, non-cancerous bumps that are pink or skin-colored
-Cysts: Fluid-filled, almost always non-cancerous, often indistinguishable from chalazion or stye
Ptosis of the eyelid
Drooping of the upper eyelid
Trichiasis
Inward growth of eye lashes
Trichinosis
Roundworm infection that can cause chronic lid edema
Exophthalamos
Forward bulging of the eyeballs
-Eye feels dry, gritty due to air exposure
MC cause of Exopthalamos
Hyperthyroidism (Grave’s Disease)
Lid lag sign
When patient looks down after looking up, lid is slow to move down
Treatment of Exopthalamos
Depends on cause:
-Grave’s Disease: Radioactive iodine kills thyroid
-Eyelid surgery
Conjunctivitis
Inflammation of the conjunctiva (pink eye)
-Produces yellow or green discharge
How is conjunctivitie commonly caused
Bacterial infection (highly contagious)
-Can also be caused by viral infection (highly contagious)
-Can also be caused by allergies (itching)
Treatment of Conjunctivitis
-Bacterial: Clean eyelids, antibiotic drops, launder washcloths, keep hands away from eyes
-Viral: Warm compress
-Allergic: Avoid allergens
Subconjunctival Hemorrhage
-Leakage of blood b/w conjunctiva and sclera
-Alarming bight red patch in eye-like a “puddle of blood”
-Rarely serious
-Very common: Coughing, sneezing
-See opthamologist if there is pain
Corneal Abrasions, cuts, ulcers
-Can blur vision
-May not see without special dye (fluorescein)
Foreign Bodies in Cornea may be difficult to see w/o:
Fluorescein dye
How to remove foreign bodies in cornea
- Removal by irrigation
- Hypodermic needle
- Surgery
Treatment of Corneal Abrasions, Cuts, and Ulcers
-Small Abrasions: Avoid rubbing, they will heal on their own
-Large abrasions: Leave in place; Refer to opthamologist
Scleritis & Episcleritis
-Scleritis: Inflammation of sclera (uncommon/30-60 years of age), may cause aching pain, blurred vision
-Episcleritis: Mild inflammation of the episclera (young adults), is rarely harmful
-BOTH: Violet red-patch or small bump on the white of the eye
Blocked nasolacrimal duct is called:
Dacryostenosis
Dacryocystitis
Infection of the lacrimal sac
Dry eyes is also known as:
Ketatoconjunctivitis sicca
What is the most significant cause of dry eyes
Aging
Dry eyes, mouth and mucus membranes + RA
Sjogren’s syndrome
Treatment of Dry Eyes
Tear conservation: Punctal plugs
-Anti-Inflammatory medications: Restasis
Pinguecula
Pinguecula
-A raised yellowish white mass on the bulbar conjunctiva
-Adjacent to the cornea at 3 and or 9-o’clock position
-Does NOT need to be removed
-Used eye protection to prevent pinguecula from progressing to pterygium
Pterygium
Fleshy, triangular growth of bulbar conjunctiva onto cornea at 3 or 9’o clock
-May spread across and distort cornea, causing astigmatism and blurring
-Surgical removal may be necessary
Internal Eye Conditions
MC cause of blurred vision
Refraction (Focusing) Problems
The _____ does most of the refraction of incoming light
Cornea
The _____ fine-tunes focus by changing in thickness
Lens
Perfect vision depends on:
- Perfect eyeball length: Cornea to retina
- Cornea bends light coming into the eye
- Lens tweaks the focus of the light
Myopia
“Nearsightedness”
-Objects in the distance are blurred
-Due to the eyeball being too long: front to back
-Tends to be familial
Treatment of Myopia
-Corrective lenses
-Bates Exercises
-Orthokeratology (“Ortho-K”)
-Refractive surgery
Non-surgical treatments for refraction problems
Bates method, glasses, contact lenses, Ortho-K
Surgical treatment for refraction problems
-RK, PRK, LASIK
-Intrasorneal rings
-Implantable Intra-Ocular lenses
-Clear Lens Replacement (CLR)
Bates method
Uses eye focussing exercises to attempt correction
Orthokeratology
Short-term corneal re-shaping using contacts worn at night
-Effects last for a day or two
-Especially helpful in sports
Radial Keratotomy (RK)
-A tiny knife makes multiple cuts into the cornea
-The worse the nearsightedness, the more cuts are needed
Complications of RK
-Fluctuating vision (over first few months), -Unpredictable hearing
-Weakened cornea more prone to rupture if hit correctly
-Difficulty fitting/wearing contact lenses
-Glare or haze around lights
Photorefractive Keratectomy (PRK)
Uses a laser beam to reshape the curve of the cornea
LASIK
-A more recent version of PRK
-Cornea is sliced from the side; laser beam then reshapes the tissue of the inner layer of the cornea
Hyperopia
“Farsightedness”
-Far objects are seen more clearly
-Eyeball is shorter than normal front to back
-Eye strain or headache may occur when reading for a long time
People with hyperopia are at a greater risk of:
Closed-angle glaucoma
Astigmatism
Blurred or distorted vision due to irregularities in shape of cornea or lens (9/10 times its the cornea)
Presbyopia
Caused by age-relating stiffening of the lens
-Starts in early 40s and eventually affects everyone
-Main symptom is farsightedness
Earliest sign of presbyopia
Need to hold reading material at arm’s length
Treatment of presbyopia
People w/ perfect vision/far-sighted: Reading glasses
-Near-sighted: Bifocals/trifocals, take glasses off when reading, can’t read with contacts well
Normal cup: disc ratio
<.5 the size
-Disc should always be bigger than the cup
A large optic cup can be a possible sign of:
Increased pressure, such as in glaucoma
A crescent is typically:
No big deal
Cataracts
Gradual clouding of the normal transparent lens, usually due to aging
-Proteins in the lens begin to clump together
Cataracts can be accelerated by:
Certain medications, DM, Alchoholism, smoking, long-term exposure to sun, Deficiency in anti-oxidants
Cataracts are caused by cancer
False
Inspection of Cataracts
-Opthalamoscopic exam: Notice decreased red reflex
-Direct inspection: See a cloudy whiteness when you look through the pupil
Diagnosis of Cataracts (History)
-Decreased vision
-Blurring
-Bothered by glare when light is bright (snow)
-Difficulty driving at night
Diagnosis of Cataracts (Exam)
Evaluate visual acuity with Snellen Eye Chart
-Opthalmascope: Check for whiteness in pupil area and/or interrupted red reflex
(Eye doctor would make final diagnosis)
Treatment of Cataracts
Surgical extraction is the only effective cure
-Lens is removed, replaced with plastic lens implant
-If both eyes have cataracts, the worse one is done first
Doctor may recommend cataract removal earlier if patient has:
Diabetes mellitus or retinal detachment
Recent research indicated that _____may decrease risk of cataract
Daily multivitamin
Treatment of cataracts: Process
-Incision made near the edge of the cornea
-Phacoemulsification: High frequency ultrasound waves are used to emulsify lens to be vacuumed out
-Insertion of new lens
Diabetic Retinopathy
Deterioration of blood vessels of retina in people w/ DM
-Can progress to advanced stage without symptoms
(Requires regular fundus exam)
-Chiropractors can screen for vision problems: Check visual acuity and central vision fields
Diabetic Retinopathy: Proliferative vs. Non-proliferative
-Non-proliferative form: BV are narrow, blocked, deteriorating, sometimes hemorraging/ Tiny yellow exudates form on the retina
-Proliferative form: Fragile new vessels form and grow over retina; Scar tissue may be generated pulling on the retina
Treatment of Diabetic Retinopathy
-Focus: Controlling diabetes-encourage exercise, weight loss, stress reduction, healthy diet, antioxidant supplements
-Control blood pressure
-Laser surgery (photocoagulation)
-Cryotherapy (freezing): To shrink new vessels
Amblyopia
Partial or complete loss of vision
What is the most common cause of monocular blindness
Amblyopia
Causes of amblyopia
- Strabismus: crossed eyes or wall-eye (Lazy eye)
-Weak muscles in one eye/brain only pays attention to strong eye - *Anisometropia: Eyes have unequal refractive power
-Poorer vision in one eye
Diagnosis of Strabismus/Lazy Eye
-Check for asymmetry of visual acuity (anisometropia)
-Check eye alignment: Shining pen light and looking to see if pupils are asymmetrical
-Cover/Uncover Test: Cover one eye and see if the patient can follow finger with uncovered eye
Treatment of Lazy Eye
-Eyeglasses that make the weaker eye work harder
-Patching the stronger eye to make weaker eye work harder
-Surgical correction
-All treatments are most effective if done when the child is very young
Strabismus vs. Amblyopia
-Strabismus/lazy eye: What you see looking at patient
-Amblyopia: What the patient sees, with loss of vision due to untreated strabismus or anisometropia
Papilledema
Increased intracranial pressure can push the optic disc out and blur margins
-Almost always bilateral
-Refer for MRI or CT to start determining cause
Corneal Arcus (Arcus Senilis)
A light colored ring seen at the periphery of the cornea due to lipid infiltration
-Normal in older patients, but should be evaluated in young people
Anisocoria
Unequal Pupil Size
Assessment of Anisocoria
PERRLA
> 1mm Anisocoria could indicate:
Horner’s syndrome, closed glaucoma, Adie’s syndrome, aneurysm, MS, drugs
2nd most common cause of blindness in the US
Glaucoma
Glaucoma can be caused by blocked outflow of:
Aqueous humor; increases internal eye pressure
Types of glaucoma
Open angle (chronic): 80%
Closed angle (acute): 20%
Responsibilities of the aqueous humor
-Continuously produced by ciliary body
-Circulates between anterior/posterior chambers
-Nourishes the lens and cornea
-Maintains appropriate pressure within the eyeball
-Drains into the angle in the front of the iris, though trabecular meshwork (reticulum) and then through the Canal of Schlemm
Retinal changes in glaucoma
Physiologic cup gets bigger, deeper
-Cup to disc ratio >0.5
Open-angle glaucoma
60-90% of cases (mostly older population)
-Gets worse over time, but with few or no symptoms
Open angle glaucoma: Diagnosis
-MC type of glaucoma
-No symptoms in most patients
-Screen for pressure: Tonometry is done by eye doctor (normal pressure: <20mm Hg)
-Opthalmoscopy revels cup; disc ratio > 0.5
-Exam reveals loss of peripheral vision
Treatment of Open-angle Glaucoma
-Topical medications: eye drops
-Oral medications
-Surgery: Laser trabeculoplasty
-Trabeculectomy may be required
Closed Angle Glaucoma
AKA Acute or Narrow-angle glaucoma
-Develops quickly
-Pressure causes pain, blurred vision, rainbow halos around lights, headache
-An emergency!
Closed-angle Treatment
Iridectomy
Leading cause of vision loss in people >60
Macular degeneration
Macular degeneration
Gradual development of blurred central vision, difficulty reading, and blind spots in central area of vision (peripheral vision is retained)
Risk factors of macular degeneration
-AGE: greatest risk factor
-Family history
-Cardiovascular risk
-Exposure to UV light
-Light-colored eyes/lighter skin
Dry Macular Degeneration
-MC Type
-Tissues of retina thicken and cells decay
-Yellow deposits (drusen) form on retina
Wet Macular Degeneration
-Less common but more severe
-Progresses faster
-Abnormal new blood vessels that leak blood and fluids
-Distorted vision: Straight lines appear wavy, shapes look deformed
Diagnosis of Macular Degeneration
-Snellen Chart: Decreased visual acuity
-Amsler grid: Blurred or wavy lines
-Color testing: Decreased color vision
-Fundoscopic exam: Drusen bodies, hemorrhage in the macular area
-Visual field exam: Central field defects
Managing Macular Degeneration
-Nutrition: Vitamin C, Vitamin E, Betacarotene, Zinc, Copper, Lutein
-Diet: Dark leafy green vegetables, fish, red grapes, oranges, cantaloupe, peppers, almonds
-Lifestyle: Exercise, stop smoking, lose weight, control hypertension
TX of MD (Dry/Wet)
Dry MD: None; nutrition may help slow symptoms
Wet MD: Laser surgery, photodynamic therapy, injections (VEGF)
All patients: Stop smoking, eat right, manage BP
Retinal Detachment: Signs/Symptoms
-Sensation of flashing lights
-Many floaters in field of vision
-Blurred vision
-Shadow or part of field of vision
In RD, the Retina detaches from the ______
Choroid
Rhegmatogenous (Primary) Retinal Detachment
-MC type of retinal detachment
-Almost always leads to blindness unless it is surgically repaired
Risks of primary retinal detachment
Being near sighted, family history of retinal detachment, previous eye injury, serious eye injury, age
Secondary types of retinal detachment
-Exudates/fluid accomodates behind retina without a tear or hole
-Inflammatory disease in posterior eye
-Tumor in posterior eye
Treatment of Retinal Tear or hole
-Photocoagulation: Laser beam is directed around the defect, forming a scar that holds retina to choroid
-Cryopexy: Uses intense cold to freeze the area around defect, causing a scar that holds retina to choroid
Treatment of Retinal Detachment
- Laser and cryopexy photocoagulation
- Pneumatic retinopexy: After freezing, injects bubble of gas into vitreous cavity, reattaches
- Scleral buckling: Use cryopexy first then a piece of silicone is sutured to the sclera
- Vitrectomy: Bloody or cloudy vitreous is removed
Shingles
Herpes Zoster in Opthalamic Branch of CN 5
-Refer to doctor immediately!
