Retinopathy Of Prematurity

1. Retinopathy Of Prematurity Dr Rajesh 03/12/08

2. 03/12/2008 Dr Rajesh Kumar MD, DM ( Neonatology)

3. 03/12/2008 Dr Rajesh Kumar MD, DM ( Neonatology) Cryo-ROP 10 yrs follow up The study’s 10-year follow-up report confirmed these lasting benefits: unfavorable structural outcomes were reduced from 48% to 27%, unfavorable visual outcomes (ie, best corrected visual acuity worse than 20/200) were reduced from 62% to 44%.

4. 03/12/2008 Dr Rajesh Kumar MD, DM ( Neonatology) Risk Factors Prematurity Intrauterine growth restriction Male gender Hyperoxia. Note that although the initial epidemic of ROP in the mid 20th century was due to excessive oxygen administration, this is rarely the sole cause in the modern era of saturation monitoring. Erythropoietin (in high cumulative doses), sepsis, blood transfusions, postnatal dexamethasone use and GM-IVH have been implicated as associations, but may reflect extreme prematurity and severity of illness rather than causation.

5. 03/12/2008 Dr Rajesh Kumar MD, DM ( Neonatology) Retinopathy of Prematurity Originally described as “retrolental fibroplasia” in the early 1940s, owing to (overly?) aggressive oxygen use. Nearly disappeared between 1954-1970, when oxygen use severely restricted. But now, has returned, secondary to improved neonatal practice of VLBW infants.

6. 03/12/2008 Dr Rajesh Kumar MD, DM ( Neonatology)

7. 03/12/2008 Dr Rajesh Kumar MD, DM ( Neonatology) ROP: Incidence <1000 grams: 80% <1250 grams: 60%

8. 03/12/2008 Dr Rajesh Kumar MD, DM ( Neonatology) An uncontrolled neovascular process in which retinal endothelial cells stop developing and die, then later, proliferate, migrate, organize, scar and cause a detachment of the retina ROP - What is it ?

9. 03/12/2008 Dr Rajesh Kumar MD, DM ( Neonatology) ROP - What is it ? Found in premature infants with immature retinal vasculature who have received supplemental oxygen. It is the most common cause of permanent blindness in children it lasts a lifetime

10. 03/12/2008 Dr Rajesh Kumar MD, DM ( Neonatology)

11. 03/12/2008 Dr Rajesh Kumar MD, DM ( Neonatology) ROP - Pathogenesis ROP can occur when the retinal vessels have not yet completed their centrifugal growth from the optic disc to the ora serratia. Primitive endothelial cells (“spindle cells”) form cords that canulize into capillaries and further differentiate into arterioles and venules.

12. 03/12/2008 Dr Rajesh Kumar MD, DM ( Neonatology) ROP - Pathogenesis 16 weeks of gestation - primitive spindle cells gradually grow out over the surface of the retina. 29 weeks -reached ora serrata. At this time these spindle cells start to form blood vessels. The vessels reach the anterior edge of the retina and stop their progression at about the time of birth.

13. 03/12/2008 Dr Rajesh Kumar MD, DM ( Neonatology) ROP - Pathogenesis During vasculogenesis if the retina is exposed to toxic substance or other insult normal (e.g., hypoxia, increased oxygen, shock, preterm delivery) vasculogenesis is interrupted. A sharp demarcation line appears between inner vascular and outer avascular zone. After the “injury,” vessel growth can resume normally (no ROP), or (for unknown reasons), the primitive vessels pile-up within the retina, growing without forward progress and forming a ridge of tissue.

14. 03/12/2008 Dr Rajesh Kumar MD, DM ( Neonatology) ROP - Pathogenesis The retina anterior to this line does not have an adequate oxygen supply, and probably exudes chemical signals that stimulate new vessel growth. As more new vessels grow in response to the chemical signals, they form arterio-venous shunts at the location of the barrier on the surface of the retina. This shunt gradually enlarges, becoming thicker and more elevated. The new vessels are accompanied by fibroblasts, which produce fibrous scar tissue. When this scar tissue contracts, it pulls on the retina and produces a traction retinal detachment.

15. 03/12/2008 Dr Rajesh Kumar MD, DM ( Neonatology) ROP - Pathogenesis Until completely vascularized, vasculogenesis is highly vulnerable to any sort of insult or stress, including medications, high levels of oxygen, and variations in light and temperature.

16. 03/12/2008 Dr Rajesh Kumar MD, DM ( Neonatology)

17. 03/12/2008 Dr Rajesh Kumar MD, DM ( Neonatology) ROP – Geography (Zones)

18. 03/12/2008 Dr Rajesh Kumar MD, DM ( Neonatology)

19. 03/12/2008 Dr Rajesh Kumar MD, DM ( Neonatology)

20. 03/12/2008 Dr Rajesh Kumar MD, DM ( Neonatology) ROP - Classification Stage 2 - ridge (R) of scar tissue and new vessels in place of the demarcation line. The white line now has width and height, and occupies some volume. Small tufts of new vessels ("popcorn vessels") may appear posterior to the ridge (arrowhead).

21. 03/12/2008 Dr Rajesh Kumar MD, DM ( Neonatology) ROP - Classification Stage 3 - Increased size of the vascular ridge (between the arrowheads), with growth of fibrovascular tissue on the ridge and extending out into the vitreous. Fibrous scar tissue is beginning to form in this stage, with attachments between the vitreous gel and the ridge.

22. 03/12/2008 Dr Rajesh Kumar MD, DM ( Neonatology) ROP - Classification Stage 4 - Partial retinal detachment. Stage 4A - detachment does not include the macula, and the vision may be good. In Stage 4B - macula is detached, and the visual potential is markedly decreased. Stage 5 - Complete retinal detachment.

23. 03/12/2008 Dr Rajesh Kumar MD, DM ( Neonatology) ROP - Classification Plus disease - engorgement and tortuosity of the blood vessels near the optic nerve. Also includes growth and dilation of abnormal blood vessels on the surface of the iris, rigidity of the iris, and vitreous haze (exudate along the retinal vessels). Can accompany any stage, but indicates greater likelihood of progression to Stage 3 (or greater).

24. 03/12/2008 Dr Rajesh Kumar MD, DM ( Neonatology)

25. 03/12/2008 Dr Rajesh Kumar MD, DM ( Neonatology)

26. 03/12/2008 Dr Rajesh Kumar MD, DM ( Neonatology)

27. 03/12/2008 Dr Rajesh Kumar MD, DM ( Neonatology) Screening: AAP Infants with a birth weight of less than 1500 g or gestational age of 32 weeks or less (as defined by the attending neonatologist) Selected infants with a birth weight between 1500 and 2000 g or gestational age of more than 32 weeks with an unstable clinical course, including those requiring cardiorespiratory support Who are believed by their attending pediatrician or neonatologist to be at high risk,

28. 03/12/2008 Dr Rajesh Kumar MD, DM ( Neonatology) UK Retinopathy of Prematurity Guideline: 2007 Treatment for ROP should be undertaken if any of the following indications are reached: Zone I, any ROP with plus disease, Zone I, stage 3 without plus disease, Zone II; stage 3 with plus disease. Treatment for ROP should be seriously considered if the following indication is reached: Zone II, stage 2 with plus disease

29. 03/12/2008 Dr Rajesh Kumar MD, DM ( Neonatology)

30. 03/12/2008 Dr Rajesh Kumar MD, DM ( Neonatology) Follow-up examinations week or less follow-up stage 1 or 2 ROP: zone I stage 3 ROP: zone II 1- to 2-week follow-up immature vascularization: zone I—no ROP stage 2 ROP: zone II regressing ROP: zone I 2-week follow-up stage 1 ROP: zone II regressing ROP: zone II 2- to 3-week follow-up immature vascularization: zone II—no ROP stage 1 or 2 ROP: zone III regressing ROP: zone III

31. 03/12/2008 Dr Rajesh Kumar MD, DM ( Neonatology) UK Retinopathy of Prematurity Guideline: 2007 All babies <32 weeks gestational age or birth weight <1501g should have their first ROP screening examination prior to discharge.

32. 03/12/2008 Dr Rajesh Kumar MD, DM ( Neonatology) Developing country criteria (LVPrasad) If United Kingdom screening criteria (birth weight 1500 g or gestational age 32 weeks, or both)2 are applied, 112 of 120 babies with severe retinopathy of prematurity would be detected and eight missed. Using United States criteria (birth weight 1500 g or gestational age 29 weeks, or both),3 we would detect 104 of 120 cases and 16 would be missed. Criteria that combine gestational age of 34 weeks and birth weight of 1750 g would identify all 120 babies, possibly missing only one (baby 41), if birth weight was a few grams higher.

33. 03/12/2008 Dr Rajesh Kumar MD, DM ( Neonatology)

34. 03/12/2008 Dr Rajesh Kumar MD, DM ( Neonatology) ROP - Management Screening: In our NICU, all infants <34 wks gestational age AND <1800 g birthweight are screened between 4-6 weeks of age.

35. 03/12/2008 Dr Rajesh Kumar MD, DM ( Neonatology)

36. 03/12/2008 Dr Rajesh Kumar MD, DM ( Neonatology) ROP - Management PREVENTION - Prevent preterm labor. (Optimal) minimum use of oxygen. Prevention of complications.

37. 03/12/2008 Dr Rajesh Kumar MD, DM ( Neonatology)

38. 03/12/2008 Dr Rajesh Kumar MD, DM ( Neonatology)

39. 03/12/2008 Dr Rajesh Kumar MD, DM ( Neonatology) ROP - Management CRYOTHERAPY For threshold ROP (stage 3 in at least 5 clock hours with plus disease) Freezing the sclera with cold probe. Multiple applications are done to the entire avascular area anterior to the neovascular ridge. Treatment of the ridge itself is avoided, since the ridge tends to bleed and cause vitreous hemorrhage if frozen. Procedure is painful and done under general anesthesia. Complications: anesthesia problems; eyelid and conjunctivae edema

40. 03/12/2008 Dr Rajesh Kumar MD, DM ( Neonatology) ROP - Management LASER PHOTOCOAGULATION Laser treatment for ROP is similar to cryotherapy. The laser spot size is smaller than a spot of cryotherapy. Usually 600-1000 spots of laser as compared to 30-50 spots of cryotherapy needed. Laser is a direct treatment of the retina and its underlying tissue instead of the entire thickness of the eye wall like in cryotherapy. Most ophthalmologists treating ROP are now using laser.

41. 03/12/2008 Dr Rajesh Kumar MD, DM ( Neonatology)

42. 03/12/2008 Dr Rajesh Kumar MD, DM ( Neonatology)

43. 03/12/2008 Dr Rajesh Kumar MD, DM ( Neonatology)

44. 03/12/2008 Dr Rajesh Kumar MD, DM ( Neonatology) UK Retinopathy of Prematurity Guideline: 2007 The unavailability of diode laser equipment or the inability to transfer to another centre should not prevent or delay the treatment of ROP. In these situations, treatment with cryotherapy or argon laser may be completed by an ophthalmologist experienced in these techniques.

45. 03/12/2008 Dr Rajesh Kumar MD, DM ( Neonatology) ROP - Management SCLERAL BUCKLEFor shallow retinal detachment - placing a silicone band around the equator of the eye to relieves the traction of the vitreous gel. VITRECTOMYFor complete retinal detachment -several small incisions into the eye with removal and replacement of the vitreous gel with a saline solution. After the vitreous has been removed, the scar tissue on the retina can be peeled or cut away, allowing the retina to relax and lay back down against the eye wall and to re-attached. The success rate ranges from 25% to 50% of patients undergoing surgery. The functional success rate is significantly lower.

46. 03/12/2008 Dr Rajesh Kumar MD, DM ( Neonatology) ROP - Scleral Buckle Silicone band (2.5mm wide) placed circumferentially around the globe Produces indentation of sclera Helps re-attach detached retina Moves sclera (and retina) towards vitreous Changes geometry of tractional forces on retina “External” approach

47. 03/12/2008 Dr Rajesh Kumar MD, DM ( Neonatology) Scleral Buckle

48. 03/12/2008 Dr Rajesh Kumar MD, DM ( Neonatology) ROP - Complications RETINAL DRAGGING AND FOLDS -Neovascular tissue may heal, but a high risk that it will contract and form a scar (“cicatrix”) that pulls and distorts the retina. The traction may drag the retina over the inside wall of the eye. May result in markedly decreased vision.

49. 03/12/2008 Dr Rajesh Kumar MD, DM ( Neonatology) ROP - Complications Dragging - yellow/white optic nerve head in the center. The retinal vessels coming from the optic nerve are dragged in the direction of the arrow by scar tissue (out of picture on the right side). The macula, which should be off the left edge of this photograph, is visible as a subtle dark area about one disc diameter to the left of the disc.

50. 03/12/2008 Dr Rajesh Kumar MD, DM ( Neonatology) ROP - Complications GLAUCOMAInfants with stage 5 ROP develop glaucoma in ~30% of cases. LATE-ONSET RETINAL DETACHMENTRetinal detachments may occur in patients with regressed ROP in the mid-teens or early adulthood as a result of increase in eye size. Late-onset retinal detachments are easier to repair and carry better prognosis. Any person with a history of ROP should have yearly retinal examinations during adolescence and early adulthood. MYOPIA - nearsightedness. STRABISMUS - crossed eyes. AMBLYOPIA - lazy eye. 

51. 03/12/2008 Dr Rajesh Kumar MD, DM ( Neonatology)

52. 03/12/2008 Dr Rajesh Kumar MD, DM ( Neonatology) ROP - Late Sequelae Myopia - 45% of patients after laser 75% of patients after scleral buckle Cataract - 5 % of patients Late retinal detachment - 4% of patients Glaucoma - 2% of patients “Dragging” of the retina and optic disc

53. 03/12/2008 Dr Rajesh Kumar MD, DM ( Neonatology)

54. 03/12/2008 Dr Rajesh Kumar MD, DM ( Neonatology) ROP - Laser Technique Laser Fill avascular retina at single sitting

55. 03/12/2008 Dr Rajesh Kumar MD, DM ( Neonatology) RetCam 120 Hand-held contact digital camera Wide-field (120 deg) 24 bit colour Robust data (quantifiable, stored images) Paramedical staff use “Telemedicine-ready”

56. 03/12/2008 Dr Rajesh Kumar MD, DM ( Neonatology) Switch from Complex assessment of entire retinal appearance to One-shot screen of disc region either for a Diagnostic examination Referral-warranted ROP One-Shot Screen

57. 03/12/2008 Dr Rajesh Kumar MD, DM ( Neonatology) Model Network

58. 03/12/2008 Dr Rajesh Kumar MD, DM ( Neonatology) ROP - What is it? An uncontrolled neovascular process in which retinal vessels proliferate, organize, migrate, scar and cause a detachment of the retina ROP is a BIOLOGIC process which we currently treat MECHANICALLY

59. 03/12/2008 Dr Rajesh Kumar MD, DM ( Neonatology)

60. 03/12/2008 Dr Rajesh Kumar MD, DM ( Neonatology) Ablative therapy indications: AAP ET ROP influence zone I ROP: any stage with plus disease zone I ROP: stage 3—no plus disease zone II: stage 2 or 3 with plus disease

61. 03/12/2008 Dr Rajesh Kumar MD, DM ( Neonatology) Treatment: AAP Treatment should generally be accomplished, when possible, within 72 hours of determination of treatable disease to minimize the risk of retinal detachment.