Posters

Extreme corneal flattening following sequential intracorneal ring implantation and corneal cross-linking

Poster Details

First Author: R.Nosé BRAZIL

Co Author(s):    E. Torres-Netto   B. Fontes                 

Abstract Details

Purpose:

To report a refractive surgery complication with associated unexpected extreme corneal flattening, thinning, opacity and hyperopic shift, four months after sequential intracorneal rings segments implantation and corneal crosslinking, in a patient with progressive and asymmetric keratoconus.

Setting:

Federal University of São Paulo, São Paulo, Brazil Centro de Microcirugia Ocular, Rio Janeiro, Brazil

Methods:

This is a case report of a 31-year-old male patient presenting progressive and markedly asymmetric keratoconus treated with sequential intracorneal rings followed by accelerated corneal collagen crosslinking (CXL). Intrastromal tunnels for implantation of ICRs were performed using a femtosecond laser. Two identical segments of ICRs, each with 200 µm of thickness and 140º arc length, were implanted opposite each other following the manufacturer’s nomogram, without any complications. Three months after the ICRs segment implantation, epithelium-off accelerated CXL treatment was performed using a UV-light source. A standard 0.1% riboflavin solution without dextran and 1.1 % hydroxypropyl methyl cellulose was used.

Results:

Four months follow-up after the last procedure, the patient returned complaining of worsening of the visual acuity. Dynamic refraction revealed a high hyperopic shift (+4.50sph -3.00cyl at 110˚), with a BCVA of 20/40, associated with central corneal opacity and an unexpected massive flattening of up to 20.3D. The central flattening attributed to the individual effect of CXL was 19.1D. The unusual combination of extreme corneal flattening, thinning and opacification observed in our patient might also represent a clinical manifestation of central toxic keratopathy (CTK).

Conclusions:

This case report an intense corneal remodeling after the combined sequential procedure of intraestromal rings implantation and CXL. Both ICR and CXL procedures are expected to cause variable degrees of corneal flattening. Not only for reporting the largest corneal flattening already described, to our knowledge this case is the first CTK-like syndrome reported after treatment with CXL. Although CTK’s pathophysiology is still unclear, the possible toxicity of the combined procedures may have triggered this condition.

Financial Disclosure:

None