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Flashcards in ophthalmology II Deck (38)
1

What is near-sightedness due to

Near-sightedness occurs when the optical power of the eye is too large and causes light to focus in front of the retina

2

what is far sightedness due to

Far-sightedness occurs when the optical power of the eye is too small and causes light to focus behind the retina

3

what is astigmatism

Astigmatism describes the shape of the cornea and causes light to focus in front or behind the retina.

4

presbyopia

another form of refractive error however it 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. Usually first occurs around 40-50 yrs. The ability to focus on near objects continues to decline throughout our lives

5

how is visual acuity tested

Standard Snellen Eye chart. Stand 20 ft away and measure one eye at a time, with glasses (or pinhole)

6

How are visual fields measured

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.

7

how is ocular motility measured

follow finger left, right, up and down

8

how are pupils tested

Are they round, reactive to light, equal,

9

how is external eye exam performed

use pen light to observe eyelids, conjunctiva, cornea and anterior chamber

10

What is the fundoscopic exam

using hand held ophthalmoscope, check red reflex, optic nerve and retina

11

causes of unilateral red eye

Viral or Bacterial Conjunctivitis, Iritis, Corneal Abrasion, Corneal Ulcer, Herpes Simplex, Herpes Zoster Ophthalmicus, Subconjunctival Hemorrhage

12

causes of bilateral red eye

dry eyes or allergic conjunctivitis

13

most common viral cause of conjunctivitis

adenovirus- or after respiratory tract infection

14

most common cause of bacterial conjunctivitis

staph aureus and strep peumoniae.

15

compare presentation of bacterial vs viral conjunctivitis

bacterial has more inflammation of conjunctiva. Viral appears more red. Bacterial will have thick, purulent discharge and eyelid can appear more swollen and almost closed

16

treatment of bacterial conjunctivits

eyedrops- Preferably 3rd or 4th generation fluoroquinolone (Ciloxan, Ocuflox, Zymaxid or Vigamox), Sulfacetamide or Tobramycin. Gentamicin drops can be toxic and cause irritation with prolonged use.

17

symptoms of iritis

ocular or periorbital eye pain, photophobia, blurred or cloudy vision, redness (near limbus), irregular shaped pupil

18

Iritis treatment

Topical Steroid Eye Drops (Pred-Forte), Dilating Eye Drops (help prevent synechiae within the eye and with pain), Occasionally Topical Glaucoma Drops

19

Causes of recurrent iritis

Ankylosing Spondylitis, Rheumatoid Arthritis, Behcet’s Disease, Crohn’s Disease, Ulcerative Colitis Lupus, Sarcoidosis, Syphilis, TB

20

Corneal abrasion - symptoms and diagnosis

severe eye pain or foreign body sensation with acute onset, tearing, blurred vision and redness. Can use fluorescein stain with blue light to see epithelial defect

21

corneal abrasions- treatment

milde: artificial tears and topical antibiotic. Large: antibiotic ointment and patching of eye, or contact lens. NO topical anesthetic eye drops b/c they delay healing

22

corneal ulcer- what is it, what causes it

Corneal ulcer is an infection of the corneal stroma.
Causes include bacterial (Staph aureus, Pseudomonas), fungal (Fusarium) and protozoa (Acanthamoeba). Caused by trauma with vegetative matter (fungal), contact lens wear (bacterial or protozoa) and risk 10 x higher for extended wear, dry eye, facial nerve paralysis.Corneal ulcer is an infection of the corneal stroma.
Causes include bacterial (Staph aureus, Pseudomonas), fungal (Fusarium) and protozoa (Acanthamoeba). Caused by trauma with vegetative matter (fungal), contact lens wear (bacterial or protozoa) and risk 10 x higher for extended wear, dry eye, facial nerve paralysis.

23

Corneal ulcer- symptoms

Acute onset with severe pain, redness, decrease in vision, eyelid swelling. White infiltrate in cornea, thinning of cornea at infiltrate, hypopyon inside anterior chamber.

24

corneal ulcer treatment

small: hourly trtmt with 4th generation fluoroquinolone. Large: require culture to determine the organism. Done with a calgi swab and placed on blood agar, Chocolate and Sabouraud’s plates. Also require fortified antibiotics including vancomycin and tobramycin. Slow healing and can leave scar with vision loss. Corneal transplant if risk of perforation
small: hourly trtmt with 4th generation fluoroquinolone. Large: require culture to determine the organism. Done with a calgi swab and placed on blood agar, Chocolate and Sabouraud’s plates. Also require fortified antibiotics including vancomycin and tobramycin. Slow healing and can leave scar with vision loss. Corneal transplant if risk of perforation

25

how are corneal foreign bodies removed

A majority of the time if the object has been present for a couple days a rust ring may develop. Needs to be removed with a diamond burr.

26

What is dry eye -symptoms

Dry eyes is a common disorder of the tear film. Symptoms include foreign body sensation, blurred vision, reflex tearing. Condition worsens towards end of the day and activities that require attention – reading, computer work. Environmental influences

27

Causes of dry eye

Systemic Conditions: rheumatoid arthritis, lupus, Grave’s disease. Medications: anti-histamines, pain medication, anti-depressants. Environmental

28

Dry eye diagnosis and treatment

Schirmers test and corneal staining patter. Artificial tears, Flax seed oil, Omega-3 vitamins. Medicated eye drops to help improve tear production (restasis). Modification of oral medications, treatment of any underlying systemic disease, Punctal plugs

29

allergic conjunctivitis treatment

v Avoidance of the offending allergen
Topical antihistamines (Zaditor, Naphcon-A)
Topical mast cell stabilizers/antihistamines (Patanol, Bepreve, Elestat)
Topical steroids (FML, Pred-Forte)
v Avoidance of the offending allergen
Topical antihistamines (Zaditor, Naphcon-A)
Topical mast cell stabilizers/antihistamines (Patanol, Bepreve, Elestat)
Topical steroids (FML, Pred-Forte)

30

How does herpes simplex affect eye

Herpetic keratitis- red eye. Primarily from HSV-1 infection of corneal epithelium. unilateral eye redness (can be bilateral), pain, photophobia, decreased vision, and tearing

31

Herpetic keratitis- diagnosis and treatment

Fluorescein on the ocular surface shows dendritic epithelial ulcer in branching pattern with terminal bulbs. Most cases will resolve spontaneously within three weeks. Medication can shorten the duration.
Topical trifluridine Q2H. Oral acyclovir 400mg 5x/day or valacyclovir 1g TID. May develop scar after healing causing blurred vision
Fluorescein on the ocular surface shows dendritic epithelial ulcer in branching pattern with terminal bulbs. Most cases will resolve spontaneously within three weeks. Medication can shorten the duration.
Topical trifluridine Q2H. Oral acyclovir 400mg 5x/day or valacyclovir 1g TID. May develop scar after healing causing blurred vision

32

Herpes zoster ophthalmicus- cuase, symptoms

reactivation of VZV. Dermatological involvement of V1 distribution. Symptoms include prodromal period of fatigue, low-grade fever, unilateral rash on forehead, upper eyelid and nose. Ocular manifestations more likely if Hutchnison sign (lesion on nose) b/c both are innervated by nasociliary nerve.

33

Herpes zoster ophthalmicus- treatment

oral acyclovir, oral valacyclovir. May develop chronic dry eye and infections

34

What is pterygium

Benign fibrocascular tumor, UV induced. Often becomes inflammed. Treatment: Artificial tears, Sunglasses, Vasoconstrictors (short-term). Conjunctival Autograft with Tissel glue.

35

angle closure glaucoma- symptoms, exam, treatment

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. treatment: laseral peripheral iridotomy

36

open angle glaucoma- cause, risk factors, symptoms

Progressive disease of the optic nerve that is often associated with elevated intraocular pressure. Leads to nerve damage and enlarged optic nerve.
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.

37

cataracts- what are they, symptoms

Gradual clouding of the eye’s natural lens. progressive decline in vision as it obstructs light from entering the eye. Color desaturation, night time glare and halos. Develop with age, diabetes, steroids, trauma, radiation

38

cataract treatment

remove lens and replace with artificial lens