Sandoval-Sánchez AH, Velasco-Ramos R, Baca-Lozada O, Viggiano-Austria D, Babayán-Sosa A

Language: Spanish
References: 15
Page: 241-245
PDF size: 437.49 Kb.

ABSTRACT

Purpose: To determine the effects of intrastromal corneal ring segments implantation on contrast sensitivity (CS).
Methods: This prospective, comparative and longitudinal study included 18 eyes of 13 patients with keratoconus, who underwent implantation of intrastromal corneal ring segments. Postoperative evaluations were programmed at 1 week, and 1 and 3 months after surgery. The preoperative evaluation included uncorrected visual acuity, best-corrected visual acuity and spherical equivalent. Additionally, far and near contrast sensitivities were measured at 1.5, 3, 6, 12 ad 18 cycles per degree (c/g).
Results: When compared with preoperative measurements, far CS decreased 1 week postoperatively only at the low spatial frequencies of 1.5 and 3 c/d but improved for 1 and 3 months in all spatial frequencies. One week after surgery, near CS decreased at the intermediate and high frequencies. By the 3-month visit, all eyes showed an improvement of SC near, although the changes were not significant (p›0.05). Conclusion: Implantation of intrastromal corneal ring segments improves the contrast sensitivity and the quality of vision in eyes with keratoconus.

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