A cataract is a clouding of the eye's natural lens, which lies behind the iris and the pupil. The lens works much like a camera lens, focusing light onto the retina at the back of the eye. The lens also adjusts the eye's focus, letting us see things clearly both up close and far away.
The lens is mostly made of water and protein. The protein is arranged in a precise way that keeps the lens clear and lets light pass through it.
But as we age, some of the protein may clump together and start to cloud a small area of the lens. This is a cataract, and over time, it may grow larger and cloud more of the lens, making it harder to see.
Researchers are gaining additional insights about what causes these specific types of proteins (crystallins) to cluster in abnormal ways to cause lens cloudiness and cataracts. One recent finding suggests that fragmented versions of these proteins bind with normal proteins, disrupting normal function.
Cataracts are classified as one of three types :
- A subcapsular cataract begins at the back of the lens. People with diabetes, high farsightedness or retinitis pigmentosa, or those taking high doses of steroids, may develop a subcapsular cataract.
- A nuclear cataract is most commonly seen as it forms. This cataract forms in the nucleus, the center of the lens, and is due to natural aging changes.
- A cortical cataract, which forms in the lens cortex, gradually extends its spokes from the outside of the lens to the center. Many diabetics develop cortical cataracts.
The lens is made mostly of water and protein. Specific proteins within the lens are responsible for maintaining its clarity. Over many years, the structures of these lens proteins are altered, ultimately leading to a gradual clouding of the lens. Rarely, cataracts can present at birth or in early childhood as a result of hereditary enzyme defects, and severe trauma to the eye, eye surgery, or intraocular inflammation can also cause cataracts to occur earlier in life. Other factors that may lead to development of cataracts at an earlier age include excessive ultraviolet-light exposure, diabetes, smoking, or the use of certain medications, such as oral, topical, or inhaled steroids. Other medications that are more weakly associated with cataracts include the long-term use of statins and phenothiazines.
Signs and symptoms
As a cataract becomes more opaque, clear vision is compromised. A loss of visual acuity is noted. Contrast sensitivity is also lost, so that contours, shadows and color vision are less vivid. Veiling glare can be a problem as light is scattered by the cataract into the eye. The affected eye will have an absent red reflex. A contrast sensitivity test should be performed and if a loss in contrast sensitivity is demonstrated an eye specialist consultation is recommended.
In the developed world, particularly in high-risk groups such as diabetics, it may be advisable to seek medical opinion if a 'halo' is observed around street lights at night, especially if this phenomenon appears to be confined to one eye only.
The symptoms of cataracts are very similar to the symptoms of ocular citrosis.
Nursing Care Plan for Cataract
- Activity / Rest: The change from the usual activities / hobbies in connection with visual impairment.
- Neurosensory: Impaired vision blurred / not clear, bright light causes glare with a gradual loss of peripheral vision, difficulty focusing work with closely or feel the dark room. Vision cloudy / blurry, looking halo / rainbow around the beam, changes eyeglasses, medication does not improve vision, photophobia (acute glaucoma).
Signs: Looks brownish or milky white in the pupil (cataract), the pupil narrows and red / hard eye and a cloudy cornea (glaucoma emergency, increased tears)
- Pain / Leisure: Discomfort light / watery eyes. Sudden pain / heavy persist or pressure on or around the eyes, headaches.
Nursing Diagnosis and Nursing Interventions
- High risk of injury related to loss of vitreous, intraocular hemorrhage, increased IOP
Marked by :
- Any signs of cataract decreased visual acuity
- Blurred vision, etc.
Expressing understanding of the factors involved in the possibility of injury.
Expected Results :
- Indicates changes in behavior, lifestyle to reduce risk factors and to protect themselves from injury.
- Changing the environment as an indication to increase security.
Nursing Intervention :
- Discuss what happens on the condition of post-surgery, pain, limitation of activity, performance, bandage the eye.
- Give the patient the position back, head high, or tilted to the side that is not ill, according to patient preference.
- Limit activities such as moving heads suddenly, scratched eyes, bent over.
- Ambulation with assistance: give special bathroom when recovering from anesthesia.
- Encourage deep breathing, coughing to maintain a healthy lung.
- Encourage use stress management techniques.
- Maintain eye protection as indicated.
- Ask the client to distinguish between discomfort and a sudden sharp pain, Investigate anxiety, disorientation, impaired bandage.
- Provide appropriate indication of antiemetic drugs, Asetolamid, analgesics.
- Impaired sensory perception: the perceptual vision, related to impaired sensory reception / status of sensory organs, a therapeutic environment is limited.
Marked by :
- Reduced visual acuity
- Changes in response to the stimuli normally.
Improved visual acuity within the limits of individual situations, recognize sensory disturbance and compensated against changes.
Expected Results :
- Know the sensory disturbances and compensated against changes.
- Identify / fix potential hazards in the environment.
Nursing Intervention :
- Determine visual acuity, note whether one or two eyes involved.
- Orient clients to the environment
- Observation signs of disorientation.
- Approach from the side that was operated on, talk to touch.
- Note about dim or blurred vision and eye irritation, which can occur when using eye drops.
- Remind clients use of cataract glasses whose purpose enlarge approximately 25 percent, loss of peripheral vision and blind spot may exist.
- Put the items required / position call bell within reach.
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