Author:
Pedrotti Emilio,Bonacci Erika,Fasolo Adriano,Longo Rosa,Pastore Giovanlorenzo,Vinciguerra Riccardo,Vinciguerra Paolo,Marchini Giorgio
Abstract
Purpose:
To evaluate corneal biomechanical changes after meniscus-shaped stromal lenticule addition keratoplasty (MS-SLAK) performed for the treatment of keratoconus.
Methods:
This interventional study included patients affected by advanced keratoconus (stage III and IV) who underwent examination with a dynamic Scheimpflug analyzer and non-contact tonometer (Corvis ST; Oculus Optikgeräte GmbH) at baseline and 12 months after MS-SLAK. The biomechanical parameters evaluated in this study were integrated inverse radius (1/R), deformation amplitude ratio (DA ratio), stiffness parameter at first applanation (SP-A1), biomechanical intraocular pressure (bIOP), central corneal thickness (CCT), and stress-strain index (SSI).
Results:
Sixteen patients were enrolled in the study. The analysis was ultimately conducted on 15 patients. Comparative analyses showed an increase in corneal stiffness as demonstrated by a rise in SSI (
P
< .0001) and SP-A1 (
P
< .0001) and a decrease in DA ratio (
P
< .0001) and 1/R (
P
= .01). A significant increase in CCT was found (
P
< .0001). No statistically significant modification was found for bIOP (
P
= .43).
Conclusions:
The corneal biomechanical analyses evaluated by the Corvis ST showed that MS-SLAK for advanced keratoconus is able to increase corneal overall stiffness. This result is explained by the significant increase in thickness induced by MS-SLAK.
[
J Refract Surg
. 2023;39(7):499–504.]