Lesson 7.2 Eye Assessment and Health Promotion PDF

External Anatomy The eye is protected by the bony orbital cavity, surrounded by a cushion of fat. The eyelids protect the eye from injury, strong light and dust. There is an upper more mobile eyelid, and a lower eyelid. The eyelashes are located on the upper and lower eyelids an...

External Anatomy The eye is protected by the bony orbital cavity, surrounded by a cushion of fat. The eyelids protect the eye from injury, strong light and dust. There is an upper more mobile eyelid, and a lower eyelid. The eyelashes are located on the upper and lower eyelids and filter out dust and dirt. They are everted on the top and inverted on the bottom. The palpebral fissure is the open space between the eyelids. The canthus is the corner of the eye, the angle where the lids meet. There is a lateral canthus and a medial canthus. The caruncle is a small fleshy mass at the inner canthus which contains sebaceous glands. The sclera is the white outer fibrous layer of the eye. The iris is part of the middle layer of the eye that can be various colors. Its muscle fibers contract the pupil in bright light and accommodate for near vision and dilate the pupil in dim light and accommodate for far vision. The pupil is also part of the middle layer and is round, regular and black and as mentioned before can contract and dilate. Internal Anatomy When inspecting the internal eye structures, we must use an ophthalmoscope to enlarge your view of the eye. To examine the client, the room should be darkened to help dilate the pupils. You want to have the client focus on a faraway object when looking at their eyes. The ophthalmoscope should function as an appendage of your own eye, which takes practice to use. You want to put the ophthalmoscope on the same eye that you are examining on the client so that you do not bump noses. For example, if you are examining the client’s right eye, you will want to hold the ophthalmoscope up to your own right eye. When beginning your exam with the ophthalmoscope, you will want to start about 10 inches away from the client at an angle of about 15 degrees lateral from the person's line of vision. As you move closer and start to look at the eye, you will notice a red glow filling the person’s pupil, which is known as the red reflex. The red color is caused by the reflection of the ophthalmoscope light off the inner retina. Keep sight of the red reflex and move closer to the eye, if the reflex goes away, the light has wandered off the pupil and you need to adjust your angle to find it again. As you get closer to the client, adjust the lens, look for any opacities that may be cataracts. Normally none are present. Using an Ophthalmoscope to View the Internal Eye This diagram portrays the structures in the ocular fundus that you will want to inspect when using the ophthalmoscope. Follow these steps when you are checking a client’s internal eye. 1. You will first start with the optic disc. It is located on the nasal side of the retina. You will look at the color which should be creamy yellow-orange to pink, the shape which should be round or oval, the margins which should be distinct, and the cup disc ratio, which when visible, is a brighter yellow white than the rest of the disc and is not more than one half the width of the disc diameter. 2. You will then move to the retinal vessels. The eye is the only place in the body where you can view blood vessels directly. You want to see a bright red artery paired with a darker vein. The arteries will be smaller than the veins and the two may cross paths. They will show a regular decrease in caliber as they extend to the periphery. 3. You should then inspect the general background of the fundus. The color varies from light red to dark brown-red, generally corresponding with the person’s hair color. The fundus should be clear with no lesions. 4. The last area to inspect is the macula, which is located about 1-2 disc diameters away from the optic disc. It should be done last because bright light on this area can cause watering eyes and some discomfort. You want to note that the color is even and homogenous and is somewhat darker than the rest of the fundus. Subjective Data Ask the following questions when assessing a client to gather subjective data. Any difficulty seeing or blurred vision? Any blind spots? Has this come on suddenly or progressed slowly over time? In one eye or both? Do objectives appear out of focus or cloudy? Do you have a “grayness” of vision? Do you have any spots in front of your eyes? Any halos or rainbows around objects? Or do you see rings around lights? Any loss of peripheral vision? Any night blindness? Any eye pain? Describe? Did it come on suddenly? Sudden onset of eye symptoms such as pain, floaters (shade or cobwebs) blind spot or loss of peripheral vision requires emergency referral. Strabismus is the deviation in the axis of the eye. You want to ask the client if they have any history of crossed eyes now or in the past and if it occurs with eye fatigue. Diplopia is the perception of two images of a single object. You want to ask the client if they ever see double? Is it constant or does it come and go? Does it go away if you close one eye or the other? Any redness or swelling in the eyes? Any infections now or in the past? When do these occur? Is it a particular time of year? One of the things redness can occur with is conjunctivitis, more commonly known as pink eye. Any watering or excessive tearing? Any discharge? Is it hard to open your eyes in the morning? What color is the discharge and how do you remove it? Any history of eye problems such as injury or surgery? Have you ever been tested for glaucoma or have any family history of glaucoma? Glaucoma is an optic nerve neuropathy characterized by a loss of peripheral vision caused by increased intraocular pressure. Age is the primary risk factor. Do you wear glasses or contact lenses? When did you have your prescription checked? If they wear contacts, do they have any problems with them such as pain or swelling? How do you care for your contacts and how often do you change them? When was your last professional eye exam? Have you ever been tested for color blindness? Any environmental conditions at work that may affect your eyes such as metal bits, smoke? Any eye medications? Do you smoke? Objective Assessment The objective assessment consists principally of inspection. - Begin by looking for first more subtle, nonverbal signs of visual loss. - For example, a client may cock their head to one side with visual loss if they have lost some of the central vision. - Those who have lost vision on one side tend to ignore that area. - As you converse with a client, note the responses to your questions and see if the client can follow you from one side of the bed to the other side. - Does the client have to move their head, or can they follow you with just their eyes? - Look out especially for squinting or craning forward. - Look at the eyebrows for symmetry. - Normal eyebrows are present bilaterally and move symmetrically as facial expression changes and have no scaling or lesions. - The upper eyelid overlaps the superior part of the iris and approximates completely with the lower lid when closed. The skin should be intact and free of redness, swelling, discharge or lesions. The eyelashes should be evenly distributed along the lid margin and are everted at the top and inverted at the bottom. - To inspect the conjunctiva and sclera ask the person to look up. Using your thumbs, slide the lower lids down along the bony orbital rim. Do not push against the eyeball. - Inspecting the area, the eyeball looks moist and glossy. There will be numerous small blood vessels on the transparent conjunctiva and it will appear pink and should be free of exudate or lesions. The sclera should be china white. - In African American clients occasionally the sclera may have a gray-blue color and there may be small brown macules on the sclera which appear like freckles and should not be confused with foreign bodies. They also may have yellowish fatty deposits beneath the lids away from the cornea which should not be confused with the overall sclera yellowing that accompanies jaundice. - Finally inspect the cornea and the lens. Snellen Chart A Snellen chart is the most commonly used and accurate measurement of visual acuity. It has lines of the alphabet arranged in decreasing size. The chart should be positioned at eye level and the client should be standing 20 feet away. One eye should be shielded to test each eye separately. If the client wears contact lenses or glasses they should be left on, except for reading glasses because these blur distance vision. Ask the client to read the chart to the smallest line of letters they can. Record the result of the last successful line read. Indicate whether the client missed any letters or if corrective lenses were worn. Normal vision is 20/20. The top number or the numerator indicates the distance the person is standing from the chart and it will always be 20. The bottom number or the denominator gives the distance at which a person with normal vision could have read that line. For example, 20/200 means that the client could read at 20 feet what the person with normal vision could read at 200 feet, indicating that they have severe visual deficits. For people over 40 or people who report increased difficulty reading, test near vision with a handheld vision screener of various sized prints. Have them hold the card about 14 inches or 35 cm away from the eye and test each eye separately. Additional Eye Assessments The 6 extraocular eye muscles attach the eyeball to its orbit. They give the eye both straight and rotary movement. Each muscle is coordinated with one in the other eye which ensures that when the two eyes move, their axes always remain parallel. This is important because the human brain can only tolerate seeing one image. To assess the EOM function there are a few tests we want to perform. Corneal Light Reflex Test (Hirschberg Test) - The corneal light reflex test (also called the Hirschberg Test) assesses the parallel alignment of the eyes. - To begin, shine a light towards the person's eyes and have them stare straight ahead and you hold the light about 12 inches away. - You want to note the reflection of the light on the corneas, it should be in the same spot in both eyes. - The asymmetry of the light reflex indicated deviation in alignment from eye muscle weakness or paralysis. If you see this, we must perform the cover/uncover test. Cover/Uncover Test - Begin by having the client stare straight ahead at your nose. Cover one of the client’s eyes with an opaque card and watch the uncovered eye. There should be a steady, fixed gaze. If the eye jumps to fixate on the designated point, it is out of alignment. - Now uncover the eye and observe that eye, it should still be staring straight ahead, but if it jumps to re-establish fixation, eye muscle weakness exists. Repeat with the opposite eye. Diagnostic Positions Test (Six Cardinal Fields of Gaze) - Begin by instructing the client to hold their head steady and follow the movement of your finger with only their eyes. - Hold the target (your finger) back about 12 inches from their face and move it to each of the six positions pictured on this slide, hold it momentarily, and then back to center. - A normal response is that both eyes move parallel with the tes. - If eye movement is not parallel and the person is not able to move their eyes without moving their head, this indicates weakness of the EOM or dysfunction of the cranial nerve that innervates it. Confrontation Test - The confrontation test screens for loss of peripheral vision. It compares the client’s peripheral vision with the examiners, assuming that the examiner’s peripheral vision is normal. - To begin, position yourself at the client’s eye level about 2 feet away. The client will look straight at you and cover one of their eyes with an opaque card as you cover the opposite eye. You are testing the client’s uncovered eye. - Hold a wiggling finger as a target midline between you and the client and slowly advance it in from the periphery in several directions. Ask the client to say now as they first see the target, which should be the same time you first see the target. - Estimate the angle where the object is first seen. Normal results are 50 degrees upward, 90 degrees temporally, 70 degrees inferiorly and 60 degrees nasally. - If the client is unable to see the object as the examiner does, the test suggests peripheral field loss, and further tests will need to be done to confirm. In older adults, this is a screening for glaucoma. Aging Considerations and Health Promotion The loss of depth perception or central vision may occur in older adults, so we want to assess their abilities to do things such as climb stairs and drive. It is recommended for adults ages 60-65 to get annual screening exams for vision changes and age-related eye diseases such as glaucoma and cataracts. Decreased tear production may occur with aging, so we need to assess if this is happening and what they use it for. If the person has a disease that requires eye drops, it is important to assess their ability to administer their eye drops. We also need to assess if any vision changes are impairing their ability to do activities. Health Promotion Encourage the client to get regular eye exams. These are especially helpful in the eye since some conditions have no warning signs or symptoms until the disease has progressed. Make sure that the client is aware of any family history of eye disease or visual acuity problems. A healthy diet helps to promote eye health as well as a healthy weight. Clients playing sports or who have jobs where particles may get in the eyes should wear protective eyewear. Encourage clients to quit smoking or never start. Encourage wearing sunglasses that block UV rays. Remind clients to take regular breaks for the eyes, especially when looking at screens such as computers and TV’s. Remind clients to clean hands when handling contact lenses and disinfect per the manufacturer’s recommendation. They should also be sure to change or replace them per the recommendation. Encourage clients to get into the habit of cleaning hands before touching the eyes. Eye infections such as pink eye and styes are very contagious which is why we never want to share items like makeup. Remind clients that tears are an excellent way to prevent eye irritation and infection and help to keep the eyes moist and wash out dust and other foreign objects that enter the eye.