Офтальмохирургия (Apr 2020)
Femtosecond laser VisuMax application for corneal collagen crosslinking
Abstract
Introduction. Corneal collagen crosslinking is a treatment method of advanced keratoconus, improving a «compaction» thickness or increasing a strength of corneal stroma. The high functional results and the shortened postoperative periods in patients during crosslinking using a femtosecond laser determine the prospects for a further study of this trend.Purpose. To study the conditions and to apply the femtocrosslinking method based on the standard flap formation options using the VisuMax femtolaser device. Material and methods. There were 20 patients under our observation with progressive keratoconus (20 eyes) who underwent femto cross-linking of corneal collagen using a VisuMax femto-laser. All patients were examined using the standard preoperative ophthalmologic methods (visometry, tonometry, keratorefractometry, pachymetry, keratotopography). The fact of progression of keratoconus was established on the basis of dynamic fellow-up for at least 6 months. Results. Features of the method of femto-cross-linking of corneal collagen using the VisuMax are: 1) extension of the flap leg in the operating settings (the angular size of the bridge increased to 320°); 2) formation of the circular corneal pocket parallel to the front surface via the femto-laser and one arcuate corneal incision depth of 140–160 µm, and the diameter of the pocket and the arcuate cut – 7.9–8.7 mm.All patients (20 eyes, 100%) were achieved the stabilization of ecstatic process within the follow-up period of 6 and 12 months.Conclusion. The conditions for the use of a laser installation VisuMax (Carl Zeiss) using the «FLAP» program in the operation of corneal collagen femtocroslinking have been determined. The advantage of this method is to simplify the classical way of doing cross-linking and increase its effectiveness. Promising is the further study of technology, dynamic control over patients and long-term results.
Keywords
