CONTINUATION

• The eye


  • Transmits visual stimuli to the brain for interpretation
  • Functions as the organ of vision
• Eye orbit


  A round, bony hollow formed by several different bones of the skull
• In the orbit, a cushion of fat surrounds the eye
• The bony orbit and fat cushion protect the eyeball
• Evaluating vision


  1. Test distant visual acuity

  2. Test near visual acuity

  3. Test visual field for gross peripheral vision

  4. Perform corneal light test

  5. Perform cover test

  6. Perform the position test
• Distant visual acuity


  20/20 with or without corrective lenses. This means that the client can distinguish what the person with normal vision can distinguish from 20 feet away.
• Myopia (impaired far vision)

  Present when the second number in the test result is larger than the first (20/40). The higher the second number, the poorer the vision.
• Legal blindness


  Vision in the better eye with corrective lenses is 20/200 or less
• Near visual acuity


  14/14 (with or without corrective lenses). This means that the client can read what the normal eye can read from a distance of 14 inches.
• Presbyopia (impaired near vision)

  Indicated when the client moves the chart away from the eyes to focus on the print. It is caused by decreased accommodation.
• Normal peripheral vision


  The client should see the examiner's finger at the same time the examiner sees it.
• Reduced peripheral vision


  A delayed or absent perception of the examiner's finger indicates reduced peripheral vision.
• Corneal light reflex


  Assesses parallel alignment of the eyes.
• Corneal light reflex abnormalities

  • Pseudotrabismus
  • Strabismus or tropia
  • Esotropia (eye turns inward)
  • Exotropia (eye turns outward)
• Cover test


  Detects deviation in alignment or strength and slight deviations in eye movement by interrupting the fusion reflex that normally keeps the eyes parallel.
• Position test


  Assesses eye muscle strength and cranial nerve function.
• Cover test abnormalities


  • Paralytic strabismus
  • 3rd nerve paralysis (looks straight ahead)
  • 4th nerve paralysis (looks down and to the right)
  • 6th nerve paralysis (right eye moves left, left eye cannot move left)
• External eye structure assessment

  • Inspect the eyelids and eyelashes
  • Assess the ability of the eyelids to close
  • Note the position of the eyelids in comparison with the eyeball
  • Observe for redness, swelling, discharge, or lesions
  • Observe the position and alignment of the eyeball in the eye socket
  • Inspect the bulbar conjunctiva and sclera
• Normal eyelid position


  The upper lid margin should be between the upper margin of the iris and the upper margin of the pupil. The lower lid margin rests on the lower border of the iris. No white sclera is seen above or below the iris.
• Ptosis


  Drooping of the upper lid, may be attributed to oculomotor nerve damage, myasthenia gravis, weakened muscle or tissue, or a congenital disorder.
• Retracted lid margins


  Suggest hyperthyroidism.
• Normal eyelid closure


  The upper and lower lids close easily and meet completely when closed.
• Entropion


  An inverted lower lid, may cause pain and injure the cornea as the eyelash brushes against the conjunctiva and cornea.
• Ectropion


  An everted lower eyelid, results in exposure and drying of the conjunctiva.
• Normal bulbar conjunctiva and sclera

  Bulbar conjunctiva is clear, moist, and smooth. Underlying structures are clearly visible. Sclera is white.
• Conjunctivitis


  Generalized redness of the conjunctiva.
• Episcleritis


  A local, noninfectious inflammation of the sclera, usually characterized by either a nodular appearance or by redness with dilated vessels.
• Metrically aligned in sockets

  Without protruding or sinking
• Exophthalmos


  Protrusion of the eyeballs accompanied by retracted eyelid margins, characteristic of Graves' disease (a type of hyperthyroidism)
• Sunken appearance of the eyes

  May be seen with severe dehydration or chronic wasting illnesses
• Inspect the bulbar conjunctiva and sclera


  1. Have the client keep the head straight while looking from side to side then up toward the ceiling

  2. Observe clarity, color, and texture
• Normal bulbar conjunctiva


  Clear, moist, and smooth. Underlying structures are clearly visible. Sclera is white
• Deviation from normal bulbar conjunctiva


  Generalized redness suggests conjunctivitis (pink eye). Areas of dryness are associated with allergies or trauma. Episcleritis is a local, noninfectious inflammation of the sclera, usually characterized by either a nodular appearance or by redness with dilated vessels
• Inspect the palpebral conjunctiva


  1. Instruct client to look down with their eyes slightly open

  2. Grasp the client's upper eyelashes and pull the lid downward

  3. Place a cotton-tipped applicator approximately 1 cm above eyelid margin and push down with the applicator while still holding the eyelashes
• Normal palpebral conjunctiva


  The lower and upper palpebral conjunctivae are clear and free of swelling or lesions
• Deviation from normal palpebral conjunctiva

  Cyanosis of the lower lid suggests a heart or lung disorder. A foreign body or lesion may cause irritation, burning, pain and/or swelling of the upper eyelid
• Inspect the lacrimal apparatus


  Assess the areas over the lacrimal glands (lateral aspect of upper eyelid) and the puncta (medial aspect of lower eyelid)
• Normal lacrimal apparatus


  No swelling or redness should appear over areas of the lacrimal gland. The puncta is visible without swelling or redness and is turned slightly toward the eye
• Deviation from normal lacrimal apparatus

  Swelling of the lacrimal gland may be visible in the lateral aspect of the upper eyelid, caused by blockage, infection, or an inflammatory condition. Redness or swelling around the puncta may indicate an infectious or inflammatory condition. Excessive tearing may indicate a nasolacrimal sac obstruction
• Palpate the lacrimal apparatus

  1. Put on disposable gloves to palpate the nasolacrimal duct to assess for blockage

  2. Use one finger and palpate just inside the lower orbital rim