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[Penetrating re-keratoplasty a chaud using healon 5 for stabilizing the anterior chamber].

BACKGROUND
Penetrating keratoplasty in cases of perforated corneal ulcers is a technical challenge. The loss of anterior chamber volume during trephination causes irregularities of surgical margins and carries the risk of trauma to iris and crystalline lens. The highly viscous substance Healon 5 allows a deep anterior chamber to be maintained even in cases of rather large perforations.


CASE REPORT
A 34-year-old man presented with acutely perforated ulcer on the transplant-host interface. Perforating minikeratoplasty (diameter 4.5 mm) including the corneal limbus had been performed 3 years previously because of a perforated ulcer after pterygium surgery. Corneal melting extending to the visual axis required a large-diameter transplant (8.0 mm), partially including the former transplant. Before trephination the anterior chamber was restored with Healon 5. Despite the fairly large perforation site we did not note any anterior chamber shallowing during trephination. Hardly any bleeding occurred perioperatively, although deep and superficial neovascularizations in the former transplant were cut. The postoperative course was uneventful with no rise in intraocular pressure. After 4 weeks, postoperative pinhole visual acuity with the preoperative correction (1.5 dpt. cyl.) was 0.7, with a topographic astigmatism of 6.5 dpt.


CONCLUSION
In the case presented here, a regular recipient wound bed as a prerequisite for a relatively low postoperative astigmatism was created by the use of Healon 5 for anterior chamber stabilization during trephination.