Femtolaser Assisted Surgery of the First Stage of Keratoprosthesis. Results of the First Clinical Cases

Purpose: to evaluate the anatomical and clinical results of using femtosecond laser for cutting out an intrastromal pocket in a vascular leucoma during the first stage of keratoprosthesis.
Patients and methods. This article is a retrospective analysis of 3 patients who underwent the first stage of keratoprosthesis the implantation of a keratoprosthesis supporting plate into an intrastromal pocket formed using femtosecond laser in the thickness of a vascular leucoma. After applanation of the laser handle to the patient’s cornea and previously known data on the thickness of the cornea, the intrastromal pocket was positioned at a depth of 2/3 of the vascular leucoma, then the femtosecond laser was activated and the intrastromal pocket was formed. After the laser work was completed, the intrastromal pocket was revised and the supporting plate was implanted.
Results. When biomicroscopy and optical coherence tomography data measured the thickness of the cornea in the area above and below the supporting plate of the keratoprosthesis in the long-term postoperative period at a period of 6 months, in all three cases, we observe the stable position of keratoprosthesis supporting plate without any signs of protrusion and displacement. This fact made it possible to successfully perform the second stage of keratoprosthesis — installation of an optical cylinder.
Conclusions. The use of a femtosecond laser at the first stage of keratoprosthesis is a possible, safe and faster method in keratoprosthetics of vascular leucoma in patients whom optical corneal transplantation or limbal stem cell transplantation are not indicated. This technology makes it possible to form an intrastromal pocket uniformly in the thickness of the vascular leucoma of the patient’s cornea without the need for transplantation of the keratoprosthetic complex, reducing the risks of protrusion of the keratoprosthetic supporting plate in the long-term postoperative period, which ultimately allows achieving a high functional result. In addition, the use of a femtosecond laser at the first stage of keratoprosthesis reduces the overall operation time and makes this technology available for widespread use in the clinic.

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