ESCRS - FP60 - OUR METHOD TO PREVENT DEVELOPING OF POSTKERATOPLASTIC AMETROPIA AND SECONDARY ECTASIA DURING PENETRATING KERATOPLASTY

OUR METHOD TO PREVENT DEVELOPING OF POSTKERATOPLASTIC AMETROPIA AND SECONDARY ECTASIA DURING PENETRATING KERATOPLASTY

Published 2024 - 28th ESCRS Winter Meeting

Reference: FP60 | Type: Submission | DOI: 10.82333/y4az-7s21

Authors: Svetlana Izmailova 1 , Valeriia Suchkova* 1 , Artem Tsyganov 1 , Lucy Astoyan 1 , Lana Arutyunyan 1

1The Department of Anterior Segment Transplant and Optical Reconstructive Surgery, S. Fyodorov Eye Microsurgery Federal State Institution,Moscow,Russian Federation

Purpose

To develop a new algorithm of a femtosecond laser work for penetrating keratoplasty, which would allow reliable placement of a polymer device and reduce the likelihood of developing postkeratoplastic ametropia and secondary ectasia.

Setting

The study was carried out on the basis of S. Fyodorov Eye Microsurgery Federal State Institution using a femtosecond laser. We used a polymer device (intrastromal ring) manufactured at our Institution. 21 patients (22 eyes) were operated. The maximum follow-up period is 5 years. Surgery is performed under the control of intraoperative OCT.

Methods

We have developed a technique according to which the femtosecond laser create pattern "mushroom" with the formation of a "step" with an angle of 90 degrees. The diameter of the upper cut is 1 mm larger than the diameter of the lower cut. At the same time with trepanation of the stepped bed, a lamellar cut is formed, which is a continuation of the "step" to the limbus, in the form of a ring concentric to the limbus, the inner diameter is equal to the diameter of the upper cut, and the outer one exceeds it by 1 mm. The diameter of the recipient's cornea bed is 0.2 mm smaller than the corneal transplantat. The diameter of the intrastromal ring is 0.5 mm less than the diameter of the lamellar pocket. The ring is placed in the formed lamellar pocket, then the corneal transplantat is fixed to the recipient's cornea with a uninterrupted blanket suture.

Results

The femtosecond laser program developed by us makes it possible to vary the size of the pattern depending on size of patient’s cornea. We obtained a higher correctable visual acuity in patients already on 7th day after operation in the comparisson with patiens who were operated by using standard penetrating keratoplasty technology. In the late postoperative period after the removal of sutures, the patients had a shift towards hypermetropic refraction, pentacam showed us better condition of anterior and posterior corneal surface. The histology of intraoperative material in cases with re-keratoplasty showed that the process starts from periphery (recipient’s cornea).

Conclusion

With the help of femtosecond technologies, the intrastromal polymer ring places the correct position around the entire circumference and remains fixed by the surrounding tissues in its lamellar pocket, which eliminates the need for extra suturing. Even after removal of sutures, we did not face ring’s dislocation. Careful observation in the late postoperative period showed a decrease in the development of ametropia. Implantation of the ring into residual cornea prevent secondary ectasia.