Pentacam findings after implantation of intrastromal corneal rings in keratoconus

Abstract

Introduction Intrastromal corneal ring segment implantation is a minimally invasive procedure. Its main goals are to flatten and regularize the cornea, to improve uncorrected and corrected visual acuity, and to delay or even prevent a keratoplasty. ICRSs effect correlates directly to its thickness and inversely to its distance to the visual axis. Patients and methods A retrospective observational study involving 44 eyes of 44 patients was initiated. The files and pentacam printouts of 44 patients were retrospectively extracted and evaluated. The preoperative and postoperative ocular findings and pentacam parameters of anterior and posterior corneal surfaces, in addition to the pachymetry data, were recorded and analyzed. Results Forty-four patients with keratoconus were evaluated in this study. Evaluation of anterior corneal surface showed significant flattening of all keratometry readings (P < 0.001) with significant improvement of corneal astigmatism (P = 0.03), corneal asphercity (P < 0.001), the inferior-superior asymmetry (P = 0.019) and the front elevation (P = 0.005) The posterior corneal surface showed significant improvement in back elevation (P < 0.001), and the back surface asphercity showed significant prolate shift (P = 0.01). The thinnest location was significantly upward displaced towards the corneal apex. kera 355° showed a significant flattening of all keratometry readings with significant improvement of corneal astigmatism and corneal asphercity of the anterior corneal surface and the back surface asphercity showed significant prolate shift (P = 0.001). The ICRS showed a significant flattening of km (P = 0.030) and corneal asphercity of the anterior corneal surface (P = 0.046). Conclusion The intracorneal ring implantation led to improvement of the tomographic corneal parameters which was more significant at the anterior corneal surface.