CATARACT

DEFINITION:

👉Cataract is a disorder that causes the lens or its capsules to lose its transparency or become opaque.

Note: Cataract are made from a protein that has altered from its natural state,distorting and eventually prohibiting required light from entering into the retina(the part of the eye that receives light). 

Often cataracts cause no problems for many years but as the cataracts mature the cloudiness increases on the lens, the light reaching the retina decreases and significant sight loss and perhaps blindness can result.

TYPES:

✔Cataracts affecting the center of the lens (nuclear cataracts). A nuclear cataract may at first cause more nearsightedness or even a temporary improvement in your reading vision. But with time, the lens gradually turns more densely yellow and further clouds your vision.

✔Cataracts that affect the edges of the lens (cortical cataracts). A cortical cataract begins as whitish, wedge-shaped opacities or streaks on the outer edge of the lens cortex. As it slowly progresses, the streaks extend to the center and interfere with light passing through the center of the lens.

✔Cataracts that affect the back of the lens (posterior subcapsular cataracts). A posterior subcapsular cataract starts as a small, opaque area that usually forms near the back of the lens, right in the path of light. A posterior subcapsular cataract often interferes with your reading vision, reduces your vision in bright light, and causes glare or halos around lights at night.

✔Cataracts you’re born with (congenital cataracts). Some people are born with cataracts or develop them during childhood. These cataracts may be genetic, or associated with an intrauterine infection or trauma.

CAUSES:

✔Aging

✔Diabetes

✔Certain medications(.e.g steroid)

✔Trauma

✔Surgical procedure 

✔Frequent X-Ray or Radiation Transmission. 

✔Lifelong exposure to sunlight 

✔Tobacco smoking

✔Malnutrition(Diets lacking antioxidant vitamins).

Risk factors

Besides aging, other cataract risk factors include:

🌹Having parents, brothers, sisters, or other family members who have cataracts

🌹Having certain medical problems, such as diabetes

🌹Having had an eye injury, eye surgery, or radiation treatments on your upper body

🌹Having spent a lot of time in the sun, especially without sunglasses that protect your eyes from damaging ultraviolet (UV) rays

🌹People who have had the vitreous gel removed from their eye (vitrectomy) have an increased risk of cataracts.

PATHOPHYSIOLOGY:

✔Usually,the lens is made mostly of water (intraocular fluid)and protein fibres........REFER TO ANATOMY OF THE LENS.

✔Due to any of the causes(.e.g. Aging),there is chemical modification of the lens and this leads to thickening and hardening of the lens(OPACITY)

✔This change leads to clumping of the lens protein(crystallin).

✔Opacity of d lens leads to inability of the lens to refract light waves,this results in REDUCED VISUAL ACUITY with all its manifestations(list them).

Note:✏✏The ultimate clinical characteristics of cataract is REDUCED VISION/REDUCED VISUAL ACUITY...All other signs and symptoms r a manifestation of reduced vision

Clinical Manifestation:

✔Clouded, blurred or dim vision

✔Increasing difficulty with vision at night

✔Sensitivity to light and glare

✔Need for brighter light for reading and other activities

✔Seeing “halos” around lights

✔Frequent changes in eyeglass or contact lens prescription

✔Fading or yellowing of colors

✔Double vision in a single eye

DIAGNOSTIC TEST.

✔Slit-lamp examination(confirms the diagnosis of lens opacity)

✔Visual acuity testing(confirms the degree of vision loss)

✔Retinal examination(to assess the back of the eye after the pupils are dilated).

MEDICAL MGT:

✔Surgical

Note:✏Treatment for cataract is surgical removal of the lens,indicated when significant vision loss has occured.

Surgical procedures are

👉Intracapsular Cataract Extraction– The removal of the entire lens from the intact capsule. This procedure is seldom performed

👉Extracapsular Cataract Extraction- The anterior lens capsule and cortex are removed.This procedure is commonly used in patients of all ages.

✔Medications:

👉Lanosterol (To dissolve clumped protein and improve vision)

👉Nepafenac Ophthalmic(An NSAID to relieve pain,redness and swelling).

NURSING MGT:

Pre-operative care

🐒Prepare patient for cataract surgery as appropriate.

🐒Approach patient with a decreased field of vision on the side where visual perception is intact.

🐒Teach patient to turn and look in the direction in the defective visual field to compensate for the loss.

🐒Provide comfort measures and Establish a therapeutic relationship with the patient.

🐒Allow patient to express his fears and anxieties about his visual loss.

👉Patient Teaching:(Post-operative)

✏Tell the patient to avoid activities that increase intraocular preassure such as straining.

✏Urge the patient to prxotect the eye from accidental injury at night by wearing a plastic or metal shield with perforations,a shield or glasses should be worn for protection during the day.

✏Advise the patient to watch for and immediately report complication such as sharp pain in the eye that’s uncontrolled by analgesics this can be caused by hyphema(a clouding in the anterior chamber) and may herald an infection.

NURSING DIAGNOSES:

1. Disturbed sensory perception (visual) related to Changes in sensory reception/sense organ of vision status eb inability to view objects during the day (u can choose any of the symptoms).

2. Anxiety related to changes in health status eb restlessness.

3. Lack of knowledge rt unfamiliar sources of information eb pt asking too many questions. 

4. Situational Low self esteem rt Impaired self-image eb social withdrawal/inability to relate with others.

COMPLICATIONS:

⚠Eye infection 

⚠Retinal detachment 

⚠Swelling of d retina

⚠Bleeding in d eye

⚠Ongoing swelling of any part of the eye

⚠Unresolving Pain

⚠Vision loss

⚠Damage to other parts of the eye.

⚠Dislocation of the IOL implant.

PREVENTION:

NOTE: There is no proven way to prevent cataracts. But certain lifestyle habits may help slow cataract development. These include:

👉Not smoking.

👉Wearing a hat or sunglasses when you are in the sun.

👉Avoiding sunlamps and tanning booths.

👉Eating healthy foods.

👉Avoiding the use of steroid medicines when possible.

👉Keeping diabetes under control.