This article is more than 5 years old. Information may no longer be current.
Publication Exclusive: Intrastromal corneal ring segment helps correct high astigmatism after DALK
Click Here to Manage Email Alerts
Corneal transplantation has progressed significantly from full-thickness penetrating keratoplasty to selective corneal transplantation in which only the diseased portions of corneal tissue are replaced surgically with similar healthy donor tissue. This has revolutionized corneal transplantation because the healthy parts of the patient’s cornea are retained. When the endothelium is untouched surgically, this eliminates the possibility of endothelial graft rejection. The diseased portion of the cornea needs to be localized to the anterior regions of the patient’s cornea, such as in keratoconus, while the endothelium remains healthy.
When the corneal stroma is replaced almost fully or totally, as in deep anterior lamellar keratoplasty or total anterior lamellar keratoplasty, this requires corneal sutures to retain the donor corneal disc in place. The circular corneal wound along with the corneal sutures can introduce corneal astigmatism that can significantly alter the quality of postoperative vision in these procedures.
In this column, Drs. Grandin, Lotfi, Cruz Fourcade and Gordillo describe their surgical approach in reducing corneal astigmatism and improving quality of vision by using an intrastromal corneal ring segment and femtosecond laser following DALK. While this elegant surgical technique appears promising in the management of corneal astigmatism following DALK, larger patient numbers and longer follow-up are necessary to evaluate the overall long-term efficacy and reproducibility of this procedure.
Thomas “TJ” John, MD
OSN Surgical Maneuvers Editor
The purpose of this study is to describe the surgical technique and first outcomes of Intraseg intrastromal corneal ring segment (ICR) implantation, assisted with IntraLase (Abbott Medical Optics), for reducing high astigmatism in patients with previous deep anterior lamellar keratoplasty. Ametropia due to high spherical or astigmatic error is the leading cause of low vision in patients with corneal grafts. After topography-guided, selective suture removal in DALK, there are many surgical options to correct a high degree of astigmatism. They include relaxing procedures such as transverse or arcuate keratotomy, wedge resection, repeat keratoplasty, phakic IOL implantation and excimer laser photoablation techniques. Several studies have reported the use of an ICR after penetrating keratoplasty. We are using the Intraseg ICR (Gamma Vision) to treat postoperative astigmatism after DALK, assisted with femtosecond laser. We will evaluate the improvement in uncorrected distance visual acuity, corrected distance visual acuity, refractive astigmatism and topographic changes.
Patients and methods
We included our first 22 patients who underwent ICR implantation assisted with IntraLase for reducing high astigmatism after DALK with 18 months of follow-up. Complete ophthalmological examination, corneal topography and anterior segment OCT were performed preoperatively and postoperatively at 1 day, 3 days, and 1, 3, 6, 12 and 18 months.
Click here to read the full publication exclusive, Surgical Maneuvers, published in Ocular Surgery News U.S. Edition, September 25, 2016.