Opthamology II Flashcards
Refractive errors
near-sightedness, far-sightedness, astigmatism, and presbyopia
Near-sightedness
when the optical power of the eye is too large and causes light to focus in front of the retina
Far-sightedness
when the optical power of the eye is too small and causes light to focus behind the retina
Astigmatism
describes the shape of the cornea and causes light to focus in front or behind the retina.
Presbyopia
form of refractive error that results when the eye progressively losses its ability to focus on near objects. It is a symptom caused by natural aging as the lens becomes less flexible
Components of an eye exam
Visual Acuity (eye chart)
Visual Fields (Have patient look at your nose and cover one eye. Hold fingers in periphery at ask how many fingers present. Then repeat for other eye.)
Ocular Motility (track finger)
Pupils (Round, Reactive to light, Equal, Afferent pupil defect)
External Exam (eyelids, conjunctiva, cornea)
Fundoscopic Exam (red reflex, disc, retina with opthalmascope)
Unilateral causes of red eye
Conjunctivitis Iritis Corneal Abrasion Corneal Ulcer Herpes Simplex Herpes Zoster Ophthalmicus Subconjunctival Hemorrhage
Conjunctivitis
Inflammation of the conjunctiva caused by viral or bacterial infection
Complain of eye pain, discharge, blurred vision, mattering of eyelids in the morning.
Often after URI
Adenovirus
Most go away on own but can use steroids or cool compresses and artificial tears
Can use antibiotics with bacterial
Iritis
Inflammation of iris
Acute onset
Ocular or periorbital pain, photophobia, blurred or cloudy vision
May have irregularly shaped pupil
Treatment: Topical Steroid Eye Drops, Dilating Eye Drops
If recurrent infections, suspicious for: Ankylosing Spondylitis, Rheumatoid Arthritis, Behcet’s Disease, Crohn’s Disease, Ulcerative Colitis Lupus, Sarcoidosis, Syphilis, TB
Corneal Abrasion
Painful scratch involving cornea
Fluorescein stain can be used with a blue light to highlight defect
Treat mild abrasions with frequent artificial tears and topical antibiotic.
Large abrasions may require antibiotic ointment and patching of eye
Heal quickly for the most part
Corneal ulcer
Infection of corneal stroma
Bacterial, fungal
If sleep in contacts, at greater risk
Acute onset with severe pain, redness, decrease in vision, eyelid swelling
White infiltrate seen in cornea
Treatment: for small topical antibiotics; for large, culture the ulcer and put on fortified antibiotics (vanco, etc)
Slow healing, can leave scar and have permanent vision loss
Corneal Foreign Body
If removed quickly, usually no long term problems
Causes of bilateral red eye
Dry Eyes
Allergic conjunctivitis
Dry eyes
30% of population
Worse towards end of day
Reading and computer can make it worse
2 classes: body not producing enough tears (meds or systemic conditions), or tears evaporating too quickly (computer, reading, ceiling fan, etc)
Allergic conjunctivitis
when an allergen irritates the conjunctiva (bilateral and seasonal)
Symptoms include itching, eyelid swelling, redness, watery discharge
Treatment: Avoid allergen, topical antihistamines, topical mast cell stabilizers, topical steroids
Herpes Simplex
Herpetic keratitis is a common viral infection that affects the corneal epithelium primarily the HSV1
One of the most frequent causes of permanent vision loss
Present with unilateral eye redness (can be bilateral), pain, photophobia, decreased vision, and tearing.
Fluorescein on the ocular surface shows dendritic epithelial ulcer in branching pattern with terminal bulbs.
Most cases resolve spontaneously
Give topical trifluridine, oral acyclovir
Pts can have corneal scar after healed
Herpes Zoster
Prodromal period of fatigue, low-grade fever, unilateral rash on forehead, upper eyelid and nose.
unilateral eye pain, redness, decreased vision, photophobia.
Fluorescein applied to corneal surface can reveal multiple swollen lesions with staining around them.
Treatment:
Oral Acyclovir 800mg 5x/day for 10 days
Oral Valacyclovir 1g 3x/day for 10 days
Pterygium
Benign fibrocascular tumor, UV induced
Often becomes inflammed
Treatment: Artificial tears, Sunglasses, Vasoconstrictors (short-term).
Conjunctival Autograft with Tissel glue.
Subconjunctival hemorrhage
ruptured blood vessel under the conjunctiva
Usually asymptomatic but patients seek care because of the appearance
No treatment necessary
Angle closure glaucoma
Risk factors include ethnicity (Asian population), age (6th-7th decade) and hyperopia (far-sighted).
Symptoms include unilateral severe eye pain, nausea, redness, blurred vision and halos around lights.
Examination may show sluggish, mid-dilated pupil, conjunctival injection, hazy cornea and shallow anterior chamber. When palpating the eye it may feel hard.
Definitive treatment is a laser peripheral iridotomy.
More of a medical emergency!
Open angle glaucoma
Progressive disease of the optic nerve that is often associated with elevated intraocular pressure.
Other risk factors include age, ethnicity, myopia and family history.
Patients usually do not experience any symptoms as it slowly causes damage to their peripheral vision.
With elevated intraocular eye pressure, stress is placed on the optic nerve leading to nerve cell damage and consequently enlargement of the optic nerve
Cataracts
A gradual clouding of the eye’s natural lens
May cause progressive decline in vision as it obstructs light from entering the eye.
Patients may notice their vision is as they are looking through a dirty window, color de-saturation, night-time glare and halos.
Develop with age as lens proteins breakdown
Causes in younger patients may include:
Diabetes (with with poorly controlled sugars)
Steroids (used to treat rheumatoid arthritis, emphysema)
Trauma
Radiation
Treatment if severe: Cataract is replaced with an artificial lens and is necessary to allow for functional vision post-operatively.
