General
What are rods and cones?
Rods: detecting movement in peripheral fields (vision in dim light)
Cones: central vision (vision in good light)
need stimulation with colors as a kid so our rods and cones will develop
What is cataracts?
Opacity of the lens that increases with age
How do we treat glaucoma?
Eye drops that are alpha agonists/beta blockers
What test do we use to diagnose macular degeneration?
Amsler grid (lines will appear wavy if they have wet macular degeneration)
What is the difference between conductive and sensorineural hearing loss?
Conductive: sounds faint, but clear (usually from cerumen, otitis media, otosclerosis, and trauma)
Sensorineural: sound analyzed improperly (usually from degenerative, meniere's, vascular accidents, infections, toxic drugs, and auditory nerve injury)
What is retinopathy?
It is caused by damage to the blood vessels of the light-sensitive tissue at the back of the eye (retina) and can be diagnosed by fluorescein angiography, retinal photography, and ultrasound (common in diabetics)
cloudy/blurred vision, dull colors, painless, pupil discoloration, poor night vision, diplopia
tearing, blinking, corneal clouding, eyelid spasma, progressive enlargement of the eye, photophobia
What is the patho of macular degeneration/who is at risk?
-hardening of the arteries around the eye
-higher risk in caucasians, females, smokers, diabetics
What is the difference between air vs bone conduction?
Air: airflow through external and middle ear
Bone: inner ear stimulated
Symptoms of a retinal detachment and treatment
Symptoms: retina begins to detach, floating spots, sensation of veil-like coating coming up or down, flashes of light, no pain, and vision loss
Treatment: scleral buckle, laser photocoagulation, vitrectomy, pneumatic retinopexy (gas bubble In the eye)
How do we diagnose cataracts?
-Snellen visual acuity (numerator is distance from eye chart in feet and denominator is distance an eye with "normal" vision can read the line ex: 20/20)
-Dilated eye exam to see retina
What is the patho of glaucoma?
Ocular disease manifested by IOP, angle between iris and cornea narrows and trabecular meshwork not working so the increases IOP pushed optic disc back and changes peripheral vision
Wet: neovascularization (new blood vessels form), straight lines appear wavy or bent, loss of central vision
Describe the Weber test
Weber: unilateral hearing loss
-conductive loss: sounds louder in affected ear
-senorineural: sounds louder in unaffected ear
What is a retinoblastoma, and how do we diagnose/treat it?
Treatment: remove the tumor (most likely removing the eye and having a glass eye in place)
Treatment options for cataracts
-phacoemulsification (ultrasonic probe is used to break up and remove the clouded natural lens)
-intraocular lens replacement (remove lens and put new lens implant in)
How do we diagnose glaucoma?
-Tonometry (inner eye pressure)
-Ophthalmoscopy (shape and color of optic nerve)
-Perimetry (visual fields)
-Gonioscopy (angle in the eye where iris meets cornea)
What is dry macular degeneration s/s?
Dry: no pain, blurred vision is the most common early sign, but goes away with brighter light
Describe the Rinne test
Rinne: compare both air and bone conduction
-conductive: bone>air
-sensorineural: air>bone
How does light travel through the eye?
Cornea, anterior chamber, pupil, lens, vitrous body, retina, optic nerve
Post-op care for cataract surgery
little discomfort, eye drops (antibiotic/anti-infammatory), do not drive for 24 hours or after seen by MD, try not to bend/stoop or lift heavy objects
Acute: ophthalmic emergency (can lose vision if not treated in 24 hours), pain (nausea/vomiting), halos, vision cloudy, dilated pupils, eyes look congested
Chronic: insidious, mild discomfort, halos, difficulty adjusting to light and dark, usually both eyes, tired eyes
How do we treat macular degeneration?
photodynamic therapy, nutrition (collagen/keratin in green leafy veggies), quit smoking (main reason eldery lose their license)
How does sound travel through the ear?
auricle, ear canal, ear drum, incus, malleus, stapes, cochlea, auditory nerve