Flashcards in Corneal Disorders Deck (75):
Red flags for corneal disorders?
1. Reduction of visual acuity
2. Severe deep eye pain (NOT just an irritation)
3. Ciliary flush: A pattern of injection in which the redness is MOST pronounced in a ring at the limbus (the limbus is the transition zone between the cornea and the sclera)
5. Severe foreign body sensation that prevents the patient from keeping the eye open
6. Corneal opacity
7. Fixed pupil
8. Severe headache with nausea
Cloudy greyness of the cornea indicates what?
How do we treat Subconjunctival Hemorrhage?
we don't. its just a popped blood vessel (not injection of conjunctiva which is stringy looking)
How do we diagnose a Subconjunctival Hemorrhage?
Normal visual acuity
Absence of discharge
Absence of photophobia
Absence of foreign body sensation
What is keratoconus?
A degenerative disorder of the eye in which structural changes within the cornea cause it to thin and change to a more conical shape than its normal gradual curve.
What is the presentation of the keratoconus?
1. Substantial distortion of vision
3. Typically diagnosed in the patient's adolescent years.
4. If both eyes, patients may have difficulty with driving or reading.
How do we treat keratoconus?
usually with corrective lenses
Further progression of the disease may need surgery. what kinds?
1. intrastromal corneal ring segments
3. mini asymmetric radial keratotomy
4. in 25% of cases, corneal transplantation
What is term most often applied to any defect in the corneal surface epithelium?
What are the different classifications of corneal abrasions?
2. Foreign-body related
3. Contact lens related
4. Spontaneous (also known as recurrent erosions-dont know what caused it)
How is traumatic corneal abrasion identified?
mechanical trauma to the eye which results in defect in epithelial surface
- usually patient can tell you how it was injured
How is foreign body related corneal abrasions identified?
Defects in corneal epithelium that are left behind after removal or spontaneous dislodging of a corneal foreign body
How do contact lens abrasions occur?
defects in corneal epithelium that are left behind after
1. removal of over-worn, improperly fitting or improperly cleaned contact lens
2. Caused by physical contact with the lens or poor handling of the lens during insertion or removal
How are recurrent (spontaneous) corneal abrasions characteristized?
a disturbance at the level of the corneal epithelial basement membrane, resulting in defective adhesions and recurrent breakdowns of the epithelium
How does a corneal abrasion present?
1. Usually a lot of eye pain (Remember… the cornea is richly innervated with sensory pain fibers)
2. Inability to open eye due to foreign body sensation
4. Patients are often too uncomfortable to work, drive, or read
Any patient who complains of eye pain with foreign body sensation preventing opening of the eye is presumed to have what until proven otherwise?
After we believe that the patient has a corneal abrasion what do we have to rule out?
1. Rule out penetrating trauma (make sure there isnt anything sticking in the eye)
2. Rule out infectious infiltrate (is it infectious or not-just a scratch)
How does the pupil usually respond in a corneal abrasion?
pupil is usually small from a reactive mitosis (pupillary constriction may be difficult to detect in light of this fact)
What should you suspect if you have a large nonreactive or irregular pupil?
injury to pupillary sphincter from penetrating trauma or blunt trauma… need to call the ophthalmologist (blown pupil)
What should you suspect when hyphema or hypopyon is present?
penetrating trauma. send straight to the ophthalmologist
What is the first thing we do when someone's chief complaint is eye pain?
ALWAYS DO A VISUAL acuity test
If you cannot disclude penetrating trauma what should you do?
discontinue the exam, shiel the eye and call the ophthomologist
In a corneal abrasion how will the vision be impaired?
It depends if its in the visual axis. If its not then the vision is normal.
If its in the visual axis then vision will be abnormal
What will be apparent on the eye after a corneal abrasion as long as its over an hour or two old?
Will there be discharge if the diagnosis is a corneal abrasion?
WIll there be corneal opacity is the diagnosis is corneal abrasion?
When should a fluoroscien stain be done?
If corneal abrasion is suspected and there is a lack of signs of other disorders
Keys to a fluoroscien stain?
1. make sure the fluoroscein strip doesnt touch any part of the eye
2. Use the magnifying glass on a head lamo or the wood's lamp
3. foreign bodies and abrasions can be very small and can easily be missed
If there is abrasions on the upper portion of the eye (linear epithelial defects) what should we look for?
suggestive of a foreign body under the lid
In the absense of contact lens what do we want to prescribe our patient for traumatic and foreign bosy abrasions?
Erythromycin and sulfacetamide OINTMENT are excellent choices.
(ointment functions as a lubricant)
Usually give every 4-6 hours.
What should we avoid with treatment in a corneal abrasion?
2. Steriods- slow epithelial healing and increase risk of infection
3. Aminoglycosides- can be toxic to epithelium
What can we prescribe for pain control for a corneal abrasion patient? 2
What do we never prescribe?
1. Cycloplegic agents (Topicamide or Cyclopentolate (Cyclogyl)
topical anesthetics = delay corneal epitheilal healing
What do cycloplegic agents do to help with eye pain?
inhibit pupil constriction to light (helps with pain
-will not usually help in foreign body injuries
Why is contact lens related abrasion treated differently?
susceptibility to infectious keratitis (inflammation of the cornea)
Whats the most common cause of infectious keratitis in the US?
contact lens wear
What are the causes of contact related infectious keratitis?
1. Pathogens will adhere to the ocular surface differently due to the presence of the contact.
2. Adhesion of pathogens to the contact lens itself
3. Colonization of solutions and lens cases
4. Warmer and more humid environment created by the lens
Patients shoould never ever be pacthed due to the risk of what infection?
What can this infection result in?
Infectious pseudomonas keratitis
corneal melting and perforation within 24 hours of infection
In a Contact Lens Related Abrasion if no infiltrate is seen what will our treatment be?
How about for pain relief? 2
topical antibiotic that is effective against Pseudomonas such as fluoroquinolone drops (ofloxacin (Ocuflox) or ciprofloxacin (Ciloxan).
Opioids as necessary
Why would you not use Erythromycin or sulfacetamide in contact related abrasion?
does not provide adequate pseudomonas coverage
For all corneal abrasions when do we follow up with the patient?
Follow up every 24 hours for subsequent evaluation until abrasion is fully healed and give careful ER instructions!!
For a foreign body injury what will our presenting symptoms be?
1. Eye pain and
2. An inability to open the eye because of foreign body sensation.
Severity ranges from a mild foreign body sensation in cases of small abrasions to excruciating pain in large abrasion.
3. Excessive tearing may occur,
4. conjunctival injection and
5. eyelid swelling may be present
If you see fluid (not tears) coming out of the eye what should you do?
Its a penetrating injury and you need to immediatly get them to ophtho
What is our treatment of foreign body injuries?
1. Inspect the eye thoroughly to identify and use fluroscein staining if necessary
2. Swab and rinse
3. Morgen lens if you have one
4. Can send patient out with a shield but not a patch
If rinse and swabbing dont work then what should we do?
Refer to someone who is trained to remove foreign bodies and treat with topical antibiotic ointment in the meantime (erythromycin)
What are corneal ulcers most likely due to?
Non-infectious causes of corneal ulcers may be complicated by infection. What are these non-infectious kinds?
Exposure keratitis (UV kerititis)
Severe dry eyes
Severe allergic eye disease (because its so irriated)
What is inflammation of the cornea called?
Presenting signs and symptoms of corneal ulcers?
3. Reduced vision
4. Red eye
5. Ciliary flush
6. Purulent or watery discharge
7. Corneal appearance is variable depending on the cause and duration of condition
What are precipitating factors for bacterial keratitis?
1. contact wear- especially overnight wear
What are the most common pathogens for bacterial keratitis?
How does the cornea look in bacterial keratitis?
hazy with central ulcer and stromal abscess
Hypopyon is often present
What can be done to identify the kind of bacteria in the eye?
gram stain or culture
How is bacterial keratitis treated?
round-the-clock high-concentration topical antibiotic
-Fluoroquinolones are preferred agents (Ciprofloxacin, ofloxacin, or norfloxacin)
The ability of herpes simplex to colonize what nerve leads to recurrent clinical problems?
What symptoms are most characteristic of herpes simplex keratitis?
Dendritic, branching ulcer
Inappropriate treatment of the ulcer caused by herpes simplex keratitis can lead to what?
-not the ulcer itself
How can herpes simplex be treated?
But what will you do as a primary care provider?
debridement and patching; +/- topical antivirals
What does stromal Herpes Simplex keratitis produce?
How do we treat this?
severe corneal opacity
(gets worse with each reoccurrence)
opical antivirals, oral antivirals, and topical steroids (BUT THIS IS DONE IN OPHTHO, NOT YOU)
When does fungal keratitis occur mostly?
After injury from plant material or agricultural setting
What patients are at higher risk of fungal infection?
chronic ocular surface disease and more commonly in contact lens wearers
How do we diagnose and treat fungal keratitis?
need stromal scrapings for culture and treatment is usually difficult
-corneal grafting may be required
Fungal keratitis is slower growing. What complications can arise from this?
because its not acute we dont notice it early and the infection often goes deeper/intraocular
Why should we never rinse contacts in tap water?
-these amoeba often cannot completely be filtered out of the tap and will infect the eye
Characteristics of Acanthamoeba Keratitis?
1. SEVERE PAIN
2. Perineural and ring infiltrates in the corneal stroma are characteristic
How can we differentiate Acanthamoeba Keratitis from ulcers?
If they are wearing SOFT contacts they dont usually cause ulcers
What kind of treatment would we have to use on a patient with Acanthamoeba Keratitis?
corneal grafting- treatment is difficult because organisms encysts in the eye
What nerve does Herpes Zoster often affect?
ophthalmic division of the trigeminal nerve
Signs and Symptoms of herpes zoster?
periorbital burning and itching
(malaise, fever, headache)
How can we predict eye involvement with herpes zoster Ophthalmicus?
rash on the tip of the nose
Ocular signs of herpes zoster Ophthalmicus? 4
2. episcleritis (inflammation of a thin layer of tissue b/w the conjunctiva and sclera)
3. anterior uveitis (inflammation of the middle layer of the eye including the iris), and often
4. increased intraocular pressure
What are possible nervous symptoms in acute stages of herpes zoster Ophthalmicus?
1. optic neuropthy
2. cranial nerve palsy
Can have chronic nerve pain in the eye
What is the treatment of herpes zoster Ophthalmicus?
oral vancycylovir (1 gram TID) started within 72 hours of rash
What does anterior uveitis require for treatment?
topical steroids and cycloplegia, so referral to Ophthalmology is recommended
If Herpes Zoster Ophthalmicus affects the retina what can it cause?