Ps

Removal of the Flieringa ring

Alternatively, this may precede the closure of the sclerotomies

PS or AS

7 In which the IOP must be very closely monitored during the first few postoperative days

8 If air is left in the AC in an aphakic eye with silicone oil implantation, the patient should not be in a face-down position for a few days to prevent silicone oil prolapse.

2.15.3.1.3 Outcomes

With regard to outcome:

• In the vast majority of the cases, the donor cornea is not rejected and remains clear. In one large study with long-term follow-up, the graft remained clear at 1 year in 65% of eyes [7]. Another large study with an average follow-up of 25 months showed that the retina was attached and the graft remained clear in 73% of eyes.

• Postoperative graft failure may or may not be caused by the fact that the transplantation was done on an acutely injured eye, but the potential risk of graft failure must not serve as a justification for not performing timely TKP vitrectomy.

• Risks for graft failure include silicone oil implantation, multiple surgeries, and retinal detachment [7]. The TKP vitrectomy offers reasonable hope to achieve functional improvement for eyes with NLP vision [4, 12] or endophthalmitis [9].

2.15.3.1.4 Eyes with Irreparable Anterior segment Damage

The TKP is useful in eyes with combined anterior- and posterior segment trauma to allow vitreoretinal surgery to be performed in a timely manner. If the cornea does not to remain clear because of major anterior segment ischemia, a permanent keratoprosthesis can be implanted instead of repeated PK procedures.6

Permanent keratoprostheses (see Chap. 3.1) are well tolerated long term, offering vision in otherwise hopeless situations; the device even allows carrying out subsequent vitrectomy procedures [2, 6, 11]. It is crucial, however, to perform the initial TKP vitrectomy early, before the retina suffers irreversible damage.

6 Careful anterior segment reconstruction, however, may alleviate the need for PK or the permanent keratoprosthesis (Fig. 2.5.4).

• carefully consider whether EAV or TKP vitrectomy is more beneficial for eyes with severe combined anterior and posterior segment trauma; if the corneal opacity is not likely to resolve within a few weeks or months, perform TKP vitrectomy

• do meticulous surgery based on a well-designed plan; this is especially important if two surgeons operate and it is questionable which surgeon should perform which maneuvers and at what time during the operation

• try to accomplish all surgical goals in a single operation; conditions may be unfavorable for another major procedure in the next few days or weeks

• delay vitrectomy or perform suboptimal vitrectomy because of reduced corneal clarity; the window of opportunity to address a serious retinal condition is very narrow

• use too small a graft; if regrafting is necessary, the new button should be smaller than the previous one

Summary

Severe posterior segment trauma and a coexisting corneal injury incompatible with intraoperative visualization of the retina should not serve as justification for abandoning the eye. Both EAV and TKP vitrectomy offer surgery without dangerous compromise on timing or completeness. The TKP allows virtually instantaneous visual rehabilitation due to corneal grafting.

References

[1] Eckardt C (1987) A new temporary keratoprosthesis for pars plana vitrectomy. Retina 7: 34-37

[2] Jahne MG (2000) 25 years Cardona keratoprosthesis after severe chemical eye burns: long-term outcome of 4 eyes. Klin Monatsbl Augenheilkd 216: 191-196

[3] Langefeld S, Kompa S, Redbrake C, Brenman K, Kirchhof B, Schrage NF (2000) Aachen keratoprosthesis as temporary implant for combined vitreoretinal surgery and keratoplasty: report on 10 clinical applications. Graefe's Arch Clin Exp Oph-thalmol 238: 722-726

[4] Morris R, Kuhn F, Witherspoon CD (1998) Management of the recently injured eye with no light perception vision. In: Alfaro V, Liggett P (eds) Vitrectomy in the management of the injured globe. Lippincott Raven, Philadelphia, pp 113-125

[5] Park S, Marcus D, Duker J, Pesavento R, Topping P, Frederick A, D'Amico D (1995) Posterior segment complications after vitrectomy for macular hole. Ophthalmology 102: 775-781

[6] Ray S, Khan BF, Dohlman CH, D'Amico DJ (2002) Management of vitreoretinal complications in eyes with permanent keratoprosthesis. Arch Ophthalmol 120:

Was this article helpful?

0 0

Post a comment