assessment of eyes for nurses and other health education

Assessment of eyes

1. Presented by: Hafsa Bibi Nursing Lecturer GCON and AHS DG.KHAN

2. Learning Objectives At the end of this lecture, students will be able to: Review the anatomy and physiology of eye and related structures. Describe the components of health history that should be elicited during the assessment of eyes. Identify the structural landmark of eye. Describe the specific assessment skills to be made during the physical examination of eye .

3. Continue: The eye transmits visual stimuli to the brain for interpretation and, in doing so, functions as the organ of vision. The eyeball is located in the eye orbit, a round, bony hollow structure 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.

4. EXTERNAL STRUCTURES OF THE EYE The eyelids (upper and lower) are two movable structures composed of skin and two types of muscle: striated and smooth. Their purpose is to protect the eye from foreign bodies and limit the amount of light entering the eye. In addition, they serve to distribute tears that lubricate the surface of the eye. The upper eyelid is larger, more mobile, and contains tarsal plates made up of connective tissue. These plates contain the meibomian glands, which secrete an oily substance that lubricates the eyelid.

5. The eyelids join at two points: the lateral (outer) canthus and medial (inner) canthus. The medial canthus contains the puncta, two small openings that allow drainage of tears into the lacrimal system, and the caruncle, a small, fleshy mass that contains sebaceous glands. The white space between open eyelids is called the palpebral fissure. When closed, the eyelids should touch. When open, the upper lid position should be between the upper margin of the iris and the upper margin of the pupil. The lower lid should rest on the lower border of the iris. No sclera should be seen above or below the limbus (the point where the sclera meets the cornea).

6. Eyelashes Eyelashes are projections of stiff hair curving outward along the margins of the eyelids that filter dust and dirt from air entering the eye.

7. The conjunctiva The conjunctiva is a thin, transparent, continuous membrane that is divided into two portions: a palpebral and a bulbar portion. The palpebral conjunctiva lines the inside of the eyelids, and the bulbar conjunctiva covers most of the anterior eye, merging with the cornea at the limbus. The point at which the palpebral and bulbar conjunctivae meet creates a folded recess that allows movement of the eyeball. This transparent membrane allows for inspection of underlying tissue and protects the eye from foreign bodies.

8. Conti … Lacrimal apparatus: This consists of gland and ducts that lubricate eye. Glands located in upper outer corner of orbital cavity. As the lid blinks tears wash across the eye then drain into puncta which is visible on upper and lower lids at inner canthus. Tears empty into lacrimal canal and are channeled into nasolacrimal sac through nasolacrimal duct , they drain into nasal meatus.

9. Conti.. Extraocular muscles : There are six muscles attached to outer surface of each eyeball, theses muscle control eye movement in six directions. 4 rectus muscles responsible for straight movement and 2 oblique muscles for diagonal movement Innervation of these muscles are supplied by three cranial nerves : the oculomotor (lll), trochlear (IV) and abducens (VI).

10. INTERNAL STRUCTURES OF THE EYE The eyeball is composed of three separate coats or layers : The external layer : Consists of the sclera and cornea. The sclera is a dense, protective, white covering that physically supports the internal structures of the eye. It is continuous anteriorly with the transparent cornea (the “window of the eye”). The cornea permits the entrance of light, which passes through the lens to the retina. It is well supplied with nerve -endings, making it responsive to pain and touch.

11. Conti.. The middle layer: Contains both an anterior portion, which includes the iris and the cilliary body, and a posterior layer, which includes the choroid. The cilliary body consists of muscle tissue that controls the thickness of the lens, which must be adapted to focus on objects near and far away.

12. The iris is a circular disc of muscle containing pigments that determine eye color. The central aperture of the iris is called the pupil. Muscles in the iris adjust to control the pupil’s size, which controls the amount of light entering the eye. The muscle fibers of the iris also decrease the size of the pupil to accommodate for near vision and dilate the pupil when far vision is needed.

13. Conti… The lens is a biconvex, transparent, avascular, encapsulated structure located immediately posterior to the iris. Suspensory ligaments attached to the ciliary body support the position of the lens. The lens functions to refract (bend) light rays onto the retina. Adjustments must be made in refraction depending on the distance of the object being viewed. Refractive ability of the lens can be changed by a change in shape of the lens (which is controlled by the ciliary body). The lens bulges to focus on close objects and flattens to focus on far objects.

14. Continue : The choroid layer contains the vascularity necessary to provide nourishment to the inner aspect of the eye and prevents light from reflecting internally. Anteriorly, it is continuous with the ciliary body and the iris.

15. Continue 3. The innermost layer: The retina, extends only to the ciliary body anteriorly. It receives visual stimuli and sends it to the brain. The retina consists of numerous layers of nerve cells, including the cells commonly called rods and cones. These specialized nerve cells are often referred to as “photoreceptors” because they are responsive to light. The rods are highly sensitive to light, regulate black-and-white vision, and function in dim light. The cones function in bright light and are sensitive to color.

16. Conti… The optic disc : It is circular area located in retina of eye toward medial side. Optic nerve enters to eyeball through this, this can be seen with ophthalmoscope is normally round and oval in shape with distinct physiologic cup. This area seen lighter / whiter than disc border. The retinal vessels: 4 sets of arterioles and venules travels through optic disc, and then bifurcate.

17. Conti… The retinal depression : Also called fovea centralis is located adjacent to optic disc, the area is surrounded by macula , which appear darker than rest of fundus. The fovea centralis and macula are highly concentrated with cons and form area of highest visual resolution and color vision.

18. Anatomy of Eye

19. The eyeball contains several chambers that maintain structure, protect against injury, and transmit light rays. 1 . The anterior chamber is located between the cornea and iris; 2. The posterior chamber is the area between the iris and the lens. These chambers are filled with aqueous humor, a clear liquid substance produced by the ciliary body. Aqueous humor helps to cleanse and nourish the cornea and lens as well as maintain intraocular pressure. The aqueous humor filters out of the eye from the posterior to the anterior chamber then into the canal of Schlemm through a filtering site called the trabecular meshwork. 3. Another chamber, the vitreous chamber, is located in the area behind the lens to the retina. It is the largest of the chambers and is filled with a vitreous humor that is clear and gelatinous.

20. VISION Visual Fields and Visual Pathways A visual field: Refers to what a person sees with one eye. The visual field of each eye can be divided into four quadrants: upper temporal, lower temporal, upper nasal, and lower nasal . The temporal quadrants: These of each visual field extend farther than the nasal quadrants. Thus, each eye sees a slightly different view but their visual fields overlap quite a bit. As a result of this, humans have binocular vision (“two-eyed” vision) in which the visual cortex fuses the two slightly different images and provides depth perception, or three-dimensional vision.

21. Continue Visual perception: Occurs as light rays strike the retina, where they are transformed into nerve impulses, conducted to the brain through the optic nerve, and interpreted. In the eye, light must pass through transparent media (cornea, aqueous humor, lens, and vitreous body) before reaching the retina. The cornea and lens are the main eye components that refract (bend) light rays on the retina. The image projected on the retina is upside down and reversed right to left from the actual image. For example, an image from the lower temporal visual field strikes the upper temporal quadrant of the retina. At the point where the optic nerves from each eyeball cross.

22. Conti… Optic chiasma The nerve fibers from the nasal quadrant of each retina (from both temporal visual fields) cross over to the opposite side. At this point, the right optic tract contains only nerve fibers from the right side of the retina and the left optic tract contains only nerve fibers from the left side of the retina. Therefore, the left side of the brain views the right side of the world.

23. Visual Reflexes The pupillary light reflex : Causes pupils immediately to constrict when exposed to bright light. This can be seen as a direct reflex, in which constriction occurs in the eye exposed to the light, or as an indirect or consensual reflex, in which exposure to light in one eye results in constriction of the pupil in the opposite eye .These protective reflexes, mediated by the oculomotor nerve, prevent damage to the delicate photoreceptors by excessive light.

24. Continue Accommodation: Is a functional reflex allowing the eyes to focus on near objects. This is accomplished through movement of the ciliary muscles, causing an increase in the curvature of the lens. This change in shape of the lens is not visible. However, convergence of the eyes and constriction of the pupils occur simultaneously and can be seen.

25. Health History Headache Change in vision , loss of vision, floaters , flashing lights Eye pain Redness , tearing Double vision ( diplopia)

26. Continue Describe any past treatments like medications , surgery, laser treatment, corrective lenses. Were these successful? Were you satisfied? Do you perform the test for macular degeneration? Do you have prescription for corrective lenses ( glasses )? Do you wear them regularly? Have you ever been tested for glaucoma , what were the results?

27. Heath History

28. Heath History

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30. Physical Assessment of Eye

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35. COLLECTING OBJECTIVE DATA: PHYSICAL EXAMINATION Preparing the Client Explain each vision test thoroughly to guarantee accurate results. For the eye examination, position the client to be seated comfortably. During examination of the internal eye with the ophthalmoscope, you will move very close to the client’s face to view the retina and internal structures. Explain to the client that this may be slightly uncomfortable. To ease any client anxiety, explain in detail what you will be doing and answer any questions the client may have. Equipment • Snellen or E chart • Hand-held Snellen card or near-vision screener • Penlight • Opaque cards • Ophthalmoscope Disposable gloves (wear as needed to prevent spreading infection or coming in contact with exudate.

36. Physical Assessment Before performing eye examination, review and recognize structures and functions of the eyes. While performing the examination, remember these key points: • Administer vision tests competently and record the results. • Use the ophthalmoscope correctly and confidently. • Recognize and distinguish normal variations from abnormal finding.

37. Hold the eyelashes against the upper ridge of the bony orbit just below the eyebrow, to maintain the averted position of the eyelid. Examine the palpebral conjunctiva for swelling, foreign bodies, or trauma. Return the eyelid to normal by moving the lashes forward and asking the client to look up and blink. The eyelid should return to normal.

38. Assessing Eye Trauma

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40. Assessing Visual Acuity

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42. Assessing Direction of Eye Movement

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44. Extraocular Muscle Movement

45. Visual Field By Confrontation Confrontation testing of visual field is a valuable screening technique for detection of lesions in anterior and posterior pathways. Combining tests to achieve best results. 1)The static finger wiggle test. 2)Kinetic red target test.

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47. Static Finger Wiggle Test

48. Kinetic Red Target Test Facing the patient move a 5mm red topped pin inward from beyond the boundary of each quadrant along a line bisecting the horizontal and vertical meridians. Ask the patient to tell when the pin first appear to b red.

49. Position And Alignment Of Eyes Stand in front of patient and survey the eyes for position and alignment , if one or both eyes seem to protrude, assess them from above. Eyebrows and Eyelids : Inspect eyebrows , noting fullness, hair distribution and scaliness. Note the position of lids , inspect width of palpebral fissure, edema, color, lesions, condition and direction, adequacy of eyelid closure.

50. Continue Lacrimal apparatus: Inspect lacrimal gland and sac for swelling, excessive tearing , dryness. Conjunctiva and sclera: Inspect sclera and conjunctiva by depressing lower lids for vascularity, nodules, swelling, obtain a fuller view of eye and ask patient to look each side and down. Cornea and Lens: With oblique light inspect any opacities in lens.

51. Pupillary Reaction To Light

52. Swinging Flashlight Test

53. The Near Reaction If reaction to light is impaired test the near reaction in both dim and normal light. Test one eye at one time. Hold finger or pencil about 10cm from patient’s eye, ask patient to look alternately at it and into distance directly behind it. Watch for pupillary constriction with near effort and convergence of eyes.

54. Ophthalmoscope Examination

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56. Continue Inspect the retinal vessels Note color, diameter and number of set of arterioles and venules Look at the AV crossings Inspect the retinal background notice its color and presence of any lesions Inspect the fovea( sharpest area of vision) and macula Inspect the anterior chamber.

57. Ophthalmoscopy:

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59. Examination Findings

60. Blepharitis

61. Chalazion

62. Stye

63. Ptosis

64. Nystagmus

65. Subconjunctival Hemorrhage

66. Hyphema

67. Anisocoria

68. Hypopyon

69. Entropion

70. Ectropion

71. Chemosis

72. Pterygium

73. Reference Bickley , L.S. ( 2009). Bate’s Guide to Physical Examination and History Taking . ( 12 th edi ). Philadelphia : Lippincott. Dooley MC, Foroozan R . Optic neuritis . J ophthalmic Vis Res. 2010; 5 : 182. Balcer LJ. Optic neuritis . N Engl J Med. 2006;354:1273.