Endothelial analysis in patients having corneal intrastromal surgery with Cornealring for correction of Keratoconus.

PURPOSE Evaluate corneal endothelium by means of specular microscopy exam in patients with Keratoconus, before and after Cornealring® corneal intrastromal ring surgery. METHODS One hundred and two eyes of 67 patients, aged between 12 and 45, with the average age of 27.31 ± 8.15 years, 30 females and 37 males, were selected to be submitted to the implant of Cornealring® corneal ring segments in pre- and post-surgery (six months after the procedure) in the External Diseases and Cornea Ward of the Instituto Panamericano da Visão. RESULTS Of the 102 eyes treated, only those that received two rings of equal thickness up to 250 µ showed statistical significance between the initial and final mean number of endothelial cells (P = 0.008), a decrease of 10.1% in the mean coefficient of variation (P = 0.003), and a 9.75% decrease in initial and final hexagonal cell counts. The other eyes receiving rings of other thicknesses showed no statistically significant differences between the mean initial and final SM examinations. CONCLUSION A longer segment is necessary for the confirmation or not of the alterations found in this study, particularly regarding the thickness of the ring used, because with the new technologies and the improvement in the result of deep lamellar transplantation, the decrease in the cell count might represent a problem in the indication of this procedure following thick corneal ring implants.