Exam 2: [ENT & Eyes] Flashcards
What are Tears composed of?
Water, Oil & Mucus
What is the Center of the Fiel of VIsion?
Fovea Centralis
Innervation of the Eye Muscles
Superior Oblique: CN 4
Lateral Rectus: CN 6
Inferior Oblique, Medial Rectus, Superior Rectus, Inferior Rectus: CN 3
Presbyopia Definition
Farsightedness caused by loss of elasticity of the lens of the eye
SNellen Chart
[Distance Vision]
- has to get more than 1/2 letters correct
- stands 20 feet away
- 20/70 = what pt reads from 20, normal eye can read from 70.
What reading on the SNellen chart is legally blind?
20/200 or worse
Rosenbaum Chart
[Near Vision]
- 14 inches from face
Ishihara Plates
[Color blindness]
- stands 75cm from plates
- must read within 3 seconds
- less than or equal to 9 correct = deficient color vision
Blind spot is where?
15 degrees temporal to the line of gaze
Anopsia Definition
[Visual Field Defect]
-hemianopia
- quadrantic defect
- mononuclear defect
Sparing of the Macula is seen when?
In Infarction of Occipital lobes due to PCA occlusion.
May be caused by collateral vascular supply to the macular region
If the Posterior cerebral artery is occulted…
Contralateral homonymous hemianopia with macular sparing
What types of light to use for Cornea & Lens, Iris & Corneal Reflection
Cornea & Lens: Oblique light
Iris: Tangenital light
Corneal Reflection: direct light
One eye vs both eyes protruding
One Eye: Cancerous growth in the eye
Both Eyes: abnormality of the thyroid
Strabismus definition
Eyes will not look straight ahead together
Lateral sparseness of the eyebrows indicates:
Hypothyroidism
Scaliness of the eyebrows indicates
Seborrheic dermatitis (dandruff)
Ptosis of the eyelids
[upper eye lid droop] (lazy eye)
NORMAL MAD = 4-4.5MM
- Upper eye lid should not cover the pupil
Myasthenia Gravis: CN III
Horner Syndrome: Congenital
Entropion of Eyelid
[Inward turning of lid margin]
- irritates conjunctiva & sclera
- MC in elderly
Ectropion of eyelid
[Outward turning of lid margin]
- If punctum turns outward, eye cant drain well
- MC in elderly
Lid Lag vs. Von Grafe’s Sign
Lid Lag: Static situation (lid higher than normal in downgaze)
Von Grafe’s: Dynamic sign (lid descends during downgaze)
Blepharitis
Chronic inflammation of eyelids at the base of the hair follicles
- S. Aureus
- Seborrheic dermatitis
- clogged sebaceous gland
- rosacea
Lesions of the Eye: Stye vs. Chalazion
Stye: Infection of margin, Ext = lash, Int = Obstructed Meibomian gland
Chalazion: Painless Obstructed Meibomian gland
Xanthelasma
Raised, yellowish cholesterol plaque on nasal portion of eyelid
- Hyperlipidemia
- Primary Biliary Cirrhosis
Pinguecula
[harmless yellow nodule in the bulbar conjunctiva]
- deposition of protein, fat or calcium
- nasal then temporal
Corneal Arcus (Arcus senilis)
- Gray/white arc around cornea
- usually benign
Kayser-Fleischer Ring
Red/brown ring shading to green or blue from Copper deposition in cornea
-Genetic OR Copper accumulation in Liver
Keratoconus
[assymetric thinning results in cone-shaped cornea]
- weakening of central cornea
Keratoconus Results In:
Myopia & Astigmatism
What CN Opens & Closes the Eye Lid?
Opens: CN 3
Closes: CN 7
Can’t close the eyes -> suspect what?
Hyperthyroidism
Bells Palsy
Loss of Conscoiusness
Corneal Injury or Infection Causes
Abrasion
Viral
Bacterial
Acute Iritis Causes
Herpes
TB
Autoimmune
Acute Angle Glaucoma Causes
Increased introcular pressure
Hyphema
[polling of blood in anterior chamber of eye]
- Results from: trauma, hemophilia
What do you inspect to cornea and lens for?
Cataracts (lens opacity)
Corneal Scars (superficial grayish white opacity of cornea)
Pterygium
Pterygium
Triangular thickening of bulbar conjunctiva that grows across the cornea
Increased introcular pressure results in a
Bulging Iris (shadow on medial iris w/ tangential lighting)