Posters

Vector analysis of corneal astigmatic changes occurring after accelerated transepithelial corneal collagen cross-linking in corneal ectasia

Poster Details

First Author: D.Piñero SPAIN

Co Author(s):    A. Guillon   A. Artola   P. Ruiz-Fortes   R. Perez-Cambrodi   R. Soto-Negro        

Abstract Details

Purpose:

To evaluate by means of vector analysis the corneal astigmatic changes occurring after transepithelial crosslinking treatment with the KXL system from Avedro in corneal ectasia during a 24-month postoperative period

Setting:

Department of Ophthalmology (OFTALMAR), Vithas Medimar International Hospital, Alicante, Spain

Methods:

A total of 34 eyes of 23 patients with ages ranging from 26 to 69 years old were included. All cases were diagnosed with corneal ectasia (31 keratoconus, 3 post-LASIK ectasia) and showed signs of progression. In all cases, transepithelial crosslinking surgery was performed using the KXL system from Avedro. Total irradiated energy was 7.2 J/cm2, ultraviolet power was 45 mW/cm2 and the treatment cycle was 2 seconds ON / 1 second OFF. Visual, refractive and corneal topographic and aberrometric changes occurring during a 24-month follow-up were evaluated. Likewise, Alpins vector analysis was used to evaluate the corneal astigmatic changes

Results:

Mean spherical equivalent was reduced from -1.6�Â�±2.3 to -1.1�Â�±1.8 D (p=0.02), with no significant changes afterwards (p=0.97). Mean corrected distance visual acuity (CDVA) improved significantly from 0.2�Â�±0.3 to 0.1�Â�±0.2 logMAR (p=0.01), with no significant changes afterwards (p=0.47). Mean ocular residual astigmatism (ORA) changed from a mean preoperative value of 2.9�Â�±1.2 D to 4.0�Â�±0.6 D at 24 months postoperatively (p=0.057). Mean difference vector was 0.5�Â�±0.4 and 0.9�Â�±0.9 D at 1 and 24 months after surgery, respectively. A significant correlation was found among the magnitude of torque and posterior corneal astigmatism (r=0.684, p=0.002).

Conclusions:

Accelerated transepithelial corneal collagen crosslinking is an effective technique for the management of progressive corneal ectasia. It induces significant changes in corneal astigmatism but without providing a predictable correction. Changes in posterior corneal astigmatism are related to misalignments of the astigmatic effect and an increase in ocular residual astigmatism

Financial Disclosure:

NONE