Persistence of the Cone on the Posterior Corneal Surface Affecting Corneal Aberration Changes After Intracorneal Ring Segment Implantation in Patients With Keratoconus

Purpose:
To analyze the changes in anterior and posterior corneal surfaces and aberrations in patients who underwent intracorneal ring segment (ICRS) implantation for the treatment of keratoconus.
Methods:
Eighty-nine eyes of 59 patients with keratoconus who underwent ICRS implantation were analyzed. All eyes were evaluated using a tomography system combining a Placido disc and Scheimpflug photography before and at least 6 months after surgery. Total, anterior, and posterior corneal aberrations, anterior and posterior sagittal and tangential anterior and posterior curve analysis, keratometry (K), minimum corneal thickness, and anterior chamber depth were analyzed before and after surgery.
Results:
Flattening with a decrease in the cone shape on the anterior corneal surface and steepening in the paracentral area with persistence of cone appearance on the posterior corneal surface were noted in all cases after ICRS implantation. The total corneal higher-order aberrations (HOAs) significantly decreased from 1.09 ± 0.43 to 0.71 ± 0.32 μm, and anterior corneal HOAs significantly decreased from 0.98 ± 0.46 to 0.81 ± 0.37 μm, whereas the posterior corneal HOAs increased from 0.53 ± 0.29 to 0.66 ± 0.25 μm after ICRS implantation (P

Source: Cornea - February 7, 2018 Category: Opthalmology Tags: Clinical Science Source Type: research