AGE RELATED CATARCT.pptx

ALL ABOUT AGE RELATED CATARACT

1. AGE RELATED CATARACT BIPIN KOIRALA HIMALAYA EYE INSTITUTE MASTER’S OF OPTOMETRY 1

2. TOPIC LAYOUT INTRODUCTION PATHOPHYSILOLOGY TYPES AND GRADING TREATMENT SUMMARY 2

3. definition The crystalline lens is a transparent structure. Its transparency may be disturbed due to degenerative process leading to opacification of lens fibers. Development of an opacity in the lens is known as cataract. 3

4. EPIDEMIOLOGY In 2020, worldwide an estimated 15.2 million (12.7-17.9) people aged 50+ years were blind, A further 78.8 million (67.2-91.4) had Severe Visual Impairment, due to cataract . In N epal cataract occupies 65 percent of total burden of blindness 4 Cataract-related blindness and vision impairment in 2020 and trends over time in relation to VISION 2020: the Right to Sight: an analysis for the Global Burden of Disease Study. Konrad Pesudovs ;  Van C Lansingh ;  John H Kempen ;  Jaimie D Steinmetz ;  Paul S Briant ;  Rohit Varma ;  Ningli Wang ;  Jost Jonas ;  Serge Resnikoff ;  Hugh R Taylor ;  Tasanee Braithwaite ;  Maria Vittoria Cicinelli ;  Theo Vos ;  Rupert R A Bourne

5. Morphological classification 5

6. Also called as ‘SENILE CATARACT ’ This is the commonest type of acquired cataract Affecting equally persons of either sex usually above the age of 50 years. By the age of 70 years, over 90% of the individuals develop senile cataract. The condition is usually bilateral, but almost always one eye is affected earlier than the other. 6

7. Classification of senile cataract 7

8. Prevalence It is very common to find nuclear and cortical senile cataracts co-existing in the same eye In general, the predominant form can be given as Cuneiform (70 %) Nuclear (25 %) Cupuliform (5 %) 8

9. Etiology / risk factors Senile cataract is essentially an ageing process. Though its precise etiopathogenesis is not clear, 9

10. Heredity. It plays a considerable role in the incidence, age of onset and maturation of senile cataract Ultraviolet irradiations. More exposure to UV irradiation from sunlight have been implicated for early onset and maturation of senile cataract 10

11. Dietary factors. Diet deficient in certain proteins, amino acids, vitamins (Riboflavin, vitamin E,C), and essential elements have also been blamed for early onset and maturation of senile cataract. Dehydrational crisis . Severe dehydrational crisis (due to diarrhoea , cholera etc.) 11

12. Smoking has also been reported to have some effect on the age of onset of senile cataract. Smoking causes accumulation of pigmented molecules—3 hydroxykynurinine and chromophores , which lead to yellowing. Cyanates in smoke causes carbamylation and protein denaturation causing opacified fibers production 12

13. Pre senile cataract???? When ??? What are the causes??? 13

14. Pre-senile cataract Pre senile cataract is the cataractous changes similar to senile cataract occur before 50 years of age. Myotonic dystrophy Diabetes Atopic dermatitis Genetic / family history 14

15. Mechanism of loss of transparency Cortical Senile Cataract. Its main biochemical features are decreased levels of total proteins, amino acids and potassium Associated with increased concentration of sodium and marked hydration of the lens Followed by coagulation of proteins. 15

16. Mechanism of cortical cataract development 16

17. Mechanism of loss of transparency Nuclear Senile Cataract. In occurs due to usual degenerative changes and agerelated nuclear sclerosis associated with dehydration and compaction of the nucleus There is significant increase in water insoluble proteins. 17

18. The total protein content and distribution of cations remain normal. May or may not be associated deposition of pigment urochrome and/or melanin derived from the amino acids in the lens 18

19. Maturation of the cortical type of senile cataract Stage of lamellar separation. Stage of incipient cataract Immature senile cataract (ISC). Mature senile cataract (MSC) Hypermature senile cataract (HMSC) 19

20. Stage of lamellar separation The earliest senile change is demarcation of cortical fibres owing to their separation by fluid. This phenomenon of lamellar separation can be demonstrated by slit-lamp examination only. These changes are reversible 20

21. Stage of incipient cataract. In this stage early detectable opacities with clear areas between them are seen Two distinct types of senile cortical cataracts can be recognized at this stage: Cuneiform senile cataract Cupuliform senile cataract 21

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23. Cupuliform cataract lies right in the pathway of the axial rays and thus causes an early loss of visual acuity 23

24. Immature senile cataract (ISC) In this stage, opacification progresses further. The cuneiform or cupuliform patterns can be well recognised . Lens appears greyish white but clear cortex is still present and so iris shadow is visible. 24

25. Lens may become swollen due to continued hydration. This condition is called ‘ intumescent cataract'. Due to swollen lens anterior chamber becomes shallow. 25

26. Mature senile cataract (MSC) In this stage, opacification becomes complete, i.e., whole of the cortex is involved. Lens becomes pearly white in colour . Such a cataract is also labelled as ‘ripe cataract’ 26

27. Hypermature senile cataract (HMSC) When the mature cataract is left in situ, the stage of hypermaturity is seen and can be of 2 types: Morgagian cataract Sclerotic type hypermature cataract 27

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29. Maturation of nuclear senile cataract The lens becomes inelastic and hard, with decrease in its ability to accommodate and obstructs the light rays. The nucleus may become diffusely cloudy ( greyish ) or tinted (yellow to black) due to deposition of pigments. In practice, the commonly observed pigmented nuclear cataracts are either amber, brown ( cataracta brunescens ) or black ( cataracta nigra ) 29

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31. 31 Brown Cataract Black Cataract

32. Clinical features Symptoms Glare Uniocular polyopia Coloured halos Black spots in front of eyes. Image blur, distortion of images Loss of vision. 32

33. Day blindness Second sight with nuclear sclerosis 33

34. Signs Visual acuity testing. Oblique illumination examination (reveals colour and appearance of the lens in pupillary area) Test for iris shadow Distant direct ophthalmoscopic examination Slit-lamp examination 34

35. Signs comparison of various cataract 35

36. Grading of nuclear cataract 36

37. cortical cataract grading (Wilmer system) 37

38. Way to estimate involved areas 38

39. Pscc grading Based on extension especiallly in vertical diameter 39

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41. Difference between NUCLEAR SCLEROSIS AND imsc 41

42. Difference between LEUCOCORIA AND msc 42

43. SOME CLINICAL PICTURES 43

44. Complications Phacoanaphylactic Uveitis . A hyper mature cataract may leak lens proteins into anterior chamber. These proteins may act as antigens and induce antigenantibody reaction leading to uveitis . 44

45. Lens-induced glaucoma It may occur by different mechanisms: Due to intumescent lens ( phacomorphic glaucoma) leakage of proteins into the anterior chamber from a hypermature cataract ( phacolytic glaucoma). 45

46. Subluxation or dislocation of lens It may occur due to degeneration of zonules in hypermature stage 46

47. MANAGEMENT OF CATARACT IN ADULTS Non-surgical measures Potassium iodide Drop Glass to avoid photophobia Mild pupillary dilator for PSCC Surgical management 47

48. Preoperative evaluation General medical examination diabetes mellitus; hypertension and cardiac problems, septic gums Ocular examination. slit-lamp biomicroscopy is desirable in all cases. 48

49. Retinal function tests Light perception (PL)/ Projection of rays (PR ) RAPD examination to rule out ON anomalies Two-light discrimination test . Maddox rod test. Colour perception. Entoptic visualisation . Laser interferometry Visiometry 49

50. Rule out infections like conjunctival infections, meibomitis , blepharitis and lacrimal sac infection. Lacrimal syringing should be carried out in each patient with history of watering from the eyes. Anterior segment evaluation by slit-lamp examination. Evaluate status of endothelium Intraocular pressure (IOP) measurement. 50

51. Indications of various surgery techniques 51

52. SICS 52

53. Phaco emulsification 53

54. Summary/ take home message 54