Cataract

Cataract content for B.SC nursing third year students

1. C A T AR A C T Ms.Towar Shilshi Asst. Prof GSON

2. INTRODUCTION Cataract is the major cause of blindness in the world. Most cataracts occur in people over 60, but it can develop at any age and babies may be born with congenital cataracts. Cataracts can also be cause by eye injury, diabetes certain medications (steroid) ultraviolet light etc.

3. DEFINITION A cataract is a lens opacity or cloudiness. Cataracts can develop in one or both eyes and at any age.

4. RISK FACTORS Increasing age (protein break in lens) Diabetes Excessive exposure to sunlight Smoking Obesity High blood pressure Previous eye injury or inflammation Previous eye surgery Prolonged use of corticosteroid medications Drinking excessive amounts of alcohol ultraviolet radiation Trauma Nutritional deficiency – vitamin - c

5. ETIOLOGICAL FACTORS Ageing factors Systemic disorders. Diabetes mellitus Down’s syndrome Ocular and systemic and congenital disorders. Trauma radiation Exposure to infrared light. Excessive use of corticosteroids. Infections (German measles, mumps, hepatitis, chickenpox)

6. Any physical or chemical cause ↓ Disturbs the intracellular and extracellular equilbrium of water and electrolytes ↓ Deranges the colloid system in lens fibres ↓ Aberrant fibres are formed from germinal epithelium of lens ↓ Epithelial cell necrosis ↓ Focal opacification of lens epithelium (glaucomflecken) ↓ Opacification of lens PATHO PHYSIOLOGY

7. Opacification of lens takeplace by 3 biochemical changes. 1. Hydration 2.Denaturation of 3.Slow lens protein sclerosis Abnormalities of lens proteins & Disorganisation of lens fibres Loss of transparency of lens Cataract

8. TYP E S It is the Most commonly occurred. Classified according to:  Morphological Classification 1. Nuclear 2. Cortical 3. Subcapsular  Maturity classification 1. Immature Cataract 2. Mature Cataract 3. Hypermature Cataract

9. CLASSIFICATION ACCORDING TO MORPHOLOGY

10. 1. Nuclear cataract Most common type Occur in the center zone of the lens (nucleus). In its early stages, as the lens changes the way it focuses light, patient may become more nearsighted or even experience a temporary improvement in reading vision. Some people actually stop needing their glasses. Unfortunately, this so-called 2 nd sight disappears as the lens gradually turns more densely yellow & further clouds vision. As the cataract progresses , the lens may even turn brown. Advanced discoloration can lead to difficulty distinguishing between shades of blue & purple.

11. 2. Cortical cataract Occur on the outer edge of the lens (cortex). Begins as whitish , wedge-shaped opacities or streaks . It slowly progresses , the streaks extend to the center and interfere with light passing through the center of the lens. Problems with glare are common with this type of cataract.

12. 3. Subcapsular cataract • • • • • • Occur just under the capsule of the lens. Starts as a small, opaque area It usually forms near the back of the lens, right in the path of light on its way to the retina. It’s interferes with reading vision Reduces vision in bright light Causes glare or halos around lights at night.

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14. CLASSIFICATION ACCORDING TO MATURITY

15. 1. Immature Cataract Lens is partially opaque Two morphological forms are seen: 1.Cuneiform Cataract: – – Wedge shaped opacities in the peripheral cortex and progress towards the nucleus. Vision is worse in low ambient light when the pupil is dilated . 1.Cupuliform Cataract: – – A disc or saucer shaped opacities beneath the posterior capsule. Vision is worse in bright ambient light when the pupil is constricted . Lens appears grayish white in color. Iris shadow can be seen on the opacity .

16. 2. Mature Cataract Lens is completely opaque . Vision reduced to just perception of light Iris shadow is not seen Lens appears pearly white Right eye mature cataract, with obvious white opacity at the centre of pupil

17. 3. Hypermature Cataract Shrunken and wrinkled anterior capsule due to leakage of water out of the lense. This may take any of two forms : 1.Liquefactive /Morgagnian Type 2.Sclerotic Cataract

18. Liquefactive/Morgagnian Type Cortex undergoes auto-lytic liquefaction and turns uniformly milky white. The nucleus loses support and settles to the bottom.

19. Sclerotic Cataract • • • The fluid from the cortex gets absorbed and the lens becomes shrunken. There may be deposition of calcific material on the lens capsule.

20. S y m p t o m s A cataract usually develops slowly , so: Causes no pain. Cloudiness may affect only a small part of the lens People may be unaware of any vision loss. Over time, however, as the cataract grows larger, it: Clouds more the lens Distorts the light passing through the lens. Impairs vision Reduced visual acuity (near and distant object) Glare in sunshine or with street/car lights. Distortion of lines. Monocular diplopia . Altered colours ( white objects appear yellowish) Not associated with pain, discharge or redness of the eye

21. S i g n s Reduced acuity . An abnormally dim red reflex is seen when the eye is viewed with an ophthalmoscope. Reduced contrast sensitivity can be measured by the ophthalmologist. Only sever dense cataracts causing severely impaired vision cause a white pupil .

22. DIAGNOSTIC STUDIES History collection and physical examination Snellen visual acuity test. Ophthalmoscopy. Slit-lamp biomicroscopic examination. Tonometry Scan ultrasound.

23. Treatment Glasses : Cataract alters the refractive power of the natural lens so glasses may allow good vision to be maintained. Surgical removal : when visual acuity can't be improved with glasses. Surgical techniques Phacoemulsification method. Extracapsular method. Intracapsular method

24. Pre-op assesments General health evaluation including blood pressure check Assessment of patients’ ability to co-operate with the procedure and lie reasonably flat during surgery Instruction on eye drop instillation The eyes should have a normal pressure, or any pre-existing glaucoma should be adequately controlled on medications. An operating microscope is needed, in order to reach the lens, a small corneal incision is made close to the limbus for the phaco-probe. It is important to appreciate anterior chamber depth and to keep all instruments away from the corneal endothelium in the plane of the iris.

25. Phacoemulsification in cataract surgery involves insertion of a tiny, hollowed tip that uses high frequency (ultrasonic) vibrations to "break up" the eye's cloudy lens (cataract). The same tip is used to suction out the lens .

26. Intra-capsular Cataract Extraction Intracapsular Cataract Extraction. From the late 1800s until the 1970s, the technique of choice for cataract extraction was intracapsular cataract extraction ( I C C E) . Th e e n t i r e le n s (ie , n u c l eu s , c o r t ex , and t h e capsule) is removed either by emulsification in place or cutting it out and artificial intraocular lens is implanted , and fine sutures close i n c i s i o n .

27. Extra-capsular Cataract Extraction (ECCE)

28. Postoperative care after cataract surgery Steroid drops (inflammation) Eg : prednisolone Antibiotic drops (infection) Eg : neomycin Avoid Very strenuous exertion (rise the pressure in the eyeball) Ocular trauma.

29. Complications of cataract surgery Infective endophthalmitis Rare but can cause permanent severe reduction of vision. Most cases within two weeks of surgery. Typically patients present with a short history of a reduction in their vision and a red painful eye. This is an ophthalmic emergency . • to serious and Suprachoroidal haemorrhage. – Severe intraoperative bleeding can lead permanent reduction in vision .

30. Uveitis Ocular perforation. Posterior capsular rupture Retinal detachment . Cystoid macular oedema G la u coma

31. NURSING MANAGEMENT

32. Provide patient verbal and written instructions about how to protect the eye, administer medications, recognize signs of complications, and obtain emergency care. Explains that there should be minimal discomfort after surgery, and instruct the patient to take a mild analgesic agent, such as acetaminophen, as needed. Antibiotic, anti-inflammatory, and corticosteroid eye drops or ointments are prescribed postoperatively