Posterior segment manifestations of penetrating ocular trauma

2. Posterior segment manifestations of penetrating ocular trauma Ghanbari MD 87:11:30 Posterior segment manifestations of ocular trauma

3. A standard classification of ocular trauma. Ophthalmology 1996; 103:240-243.

4. Ocular traumais a major cause of ocular morbidity and the leading cause of monocular visual loss.

5. Open globe rupture : occurs following blunt eye injury at the site of greatest structural weakness.

6. The initial of injury to the macula or optic nerve is critical for determining visual prognosis.

8. Ocular trauma: Initial injuries Secondary complications Wound healing Endophthalmitis Sympathetic ophthalmia

9. Primary damages: Vitreous Retina Macula Optic nerve Vesseles

10. Vitreous incarceration

12. (a) Postoperative colour fundus photo showing a laceration of the vessels at the superior aspect of the optic disc. (b) Close-up of the superior arcade showing retinal pallor, cotton wool spots and dot/blot haemorrhages.

13. (a) Colour fundus photo 6 months post-injury showing scarring and retinal striae extending across papillomacular bundle. (b) Close-up of the optic disc showing fibrotic scarring.

14. Gunshot wound

15. Giant retinal tear with retinal vessels crossing the tear. View through a superfield

16. Retinal incarceration in the posterior impact site (arrow) and the subretinal blood (curved arrow). A localized choroidal hemorrhage is seen in the foreground on the left

18. 10 Traumatic endophthalmitis (Streptococcus faecalis) at presentation after penetrating trauma. Note the marked anterior chamber fibrin, early ring infiltrate of the cornea, peripheral hypopyon, and purulent material in the area of corneal laceration

19. Factors associated with Endophthalmitis Open globe laceration. Retained IOFB. Injury by organic material. Disruption of the lens. Delay in primary closure.

20. Endophthalmitis: • 2 to 7 percent for all open globe injures. • This rate is as high as 13 percent in patients with open globe lacerations complicated by IOFBs

21. Bacillus species and coagulase-negative Staphylococcus account forup to 50 percent of endophthalmitisafter open globe injury based on intraoperative cultures.

22. Wound healing Infiltration Proliferation Scar formation

23. Subsequent wound healing TRD Intraocular proliferation, and post-traumatic PVR.

24. Among 327 patients who had an open-globe injury, PVR occurred in 64 patients (20% of eyes), with the highest frequency following perforating injury (43%).

25. Prognosis • Severity of the initial penetrating injury. • Initial visual acuity.    • RAPD.   • Injuries associated with blunt trauma.   • Large corneoscleral laceration.    • Presence of infection. • Lens damage.

26. OPEN-GLOBE INJURIES • Preoperative evaluation • VA. • RAPD. • IOP. • VEP,ERG. • Ultrasonography. • CT Scan. • MRI.

27. An open globe often has low IOP, but normal or elevated IOP does not rule out the possibility of a rupture.

28. Diffuse chemosis or subconjunctival hemorrhage suggests the presence of occult scleral rupture.

29. Repair • Running shoelace monofilament nylon sutures distribute stress evenly, are elastic and well tolerated, and may be rapidly placed. • Silk sutures are inelastic and lead to wound leaks during the vitrectomy • Absorbable sutures are inelastic and not permanent.

30. PATHOBIOLOGY OF WOUND HEALING • Open-globe injury, resulting: • Intraocular blood. • Inflammatory cell infiltration. • Blood-retina barrier breakdown.

31. PATHOBIOLOGY OF WOUND HEALING • Chemokines • Cytokines • Growth factors • Effects on the RPE. Fibroblasts. Glial cells.

32. PATHOBIOLOGY OF WOUND HEALING • Some cells develop Contractile Elements; then organized and TRD occurs.

33. Factors highly associated with RD • Blood in vitreous. • Injuries involve ora serrata.

35. Management

37. Creation of posterior vitreous detachment by a vitreoretinal pick

38. Retinal dialysis caused by traction of shrinking membrane. Location of scleral laceration (A). Vitreous membrane (B). Dialysis at vitreous base border (C).

40. Role of Vitrectomy • Vitrectomy is indicated: • Traumatic open-globe injuries with RD on presentation. • Double-penetrating injuries. • Vitreous incarceration. • Vitreous hemorrhage. • IOFBs. • Endophthalmitis.

41. MAGNETIC INTRAOCULAR FOREIGN BODIES External magnet may have a place in the management of IOFBs that are • Well visualized. • Small. • Intravitreal in location.

42. vitrectomy If signs of tissue incarceration and or fibrous encapsulation of the IOFB are present.

43. Removal of encapsulated intraocular foreign body

44. Timing of vitrectomy • Most surgeons will agree that immediate vitrectomy is indicated for • posttraumatic endophthalmitis or • IOFB with high risk of infection, but timing of surgery with other scenarios is less clear.

45. Timing of vitrectomy • Cleary and Ryan compared vitrectomy at 1, 14, and 70 days after a standardized injury with intravitreal autologous blood injection known to cause a reproducible tractional retinal detachment.

46. By day 70, most eyes already had a RD, but prevention of retinal detachment was documented with vitrectomy at both 1 and 14 days post-injury.

47. Whereas there was no significant difference between vitrectomy at 1 and 14 days with regard to its ability to prevent retinal detachment, it was noted that surgery at 1 day was technically more difficult.

48. By day 14, a posterior vitreous detachment had occurred in many cases and the vitreous was generally easier to cut.

49. Timing of Vitrectomy • Vitrectomy should be performed between 7 and 14 days after injury. • unless Angle closure from lens swelling. Endophthalmitis. • Ultrasonic evidence of RD does not necessarily indicate early vitrectomy.

50. Timing of Vitrectomy Delay for 7 to 14 days permits • PVD to occur. • Decreases choroidal swelling. • Decreases bleeding. • Better corneal clarity. • Less wound leakage. • liquefaction of the clot.