Pablo Peña-García1, Jorge L Alió2, Alfredo Vega-Estrada1, Rafael I Barraquer1. 1. From the Division of Ophthalmology (Peña-García, Alió), Universidad Miguel Hernández, and the Keratoconus Unit (Alió, Vega-Estrada), Vissum Instituto Oftalmologico de Alicante, Alicante, and Centro de Oftalmología Barraquer (Barraquer), Barcelona, Spain. 2. From the Division of Ophthalmology (Peña-García, Alió), Universidad Miguel Hernández, and the Keratoconus Unit (Alió, Vega-Estrada), Vissum Instituto Oftalmologico de Alicante, Alicante, and Centro de Oftalmología Barraquer (Barraquer), Barcelona, Spain. Electronic address: jlalio@vissum.com.
Abstract
PURPOSE: To improve the predictability of the visual and refractive outcomes of intrastromal corneal ring segment (ICRS) implantation in keratoconus patients and highlight the importance of internal astigmatism and its relationship to corneal and refractive astigmatism as prognostic factors. SETTING: Vissum Corporación, Alicante, and Centro de Oftalmología Barrquer, Barcelona, Spain. DESIGN: Retrospective case series. METHODS: Visual, refractive, topographic, and aberrometric variables were evaluated in eyes having ICRS implantation. The eyes were divided into 2 groups according to the relative position of the keratometric axis and refractive axis; that is, coincident axis (0 degree ± 15 [SD]) or uncoincident axis. Internal astigmatism was calculated by vectorial analysis. The relationship between topographic astigmatism and refractive astigmatism was evaluated. The follow-up was 6 months. RESULTS: Of the 127 eyes evaluated, 79 had grade II keratoconus and 48 had grade I keratoconus. Statistically significant differences were found in the relative position of the refractive axis and keratometric axis (P=.017). Internal astigmatism had a significant correlation with the gain in visual acuity in patients with grade II keratoconus (r = -0.455, P=.0001). This relationship was less significant in patients with grade I keratoconus (r = -0.391, P=.021). CONCLUSION: The predictability of visual and refractive outcomes can be significantly increased in grade II keratoconus patients when the relative position of the keratometric and refractive axes; the internal, corneal, and refractive astigmatism; and their combinations are used as prognostic factors. FINANCIAL DISCLOSURE: No author has a financial or proprietary interest in any material or method mentioned.
PURPOSE: To improve the predictability of the visual and refractive outcomes of intrastromal corneal ring segment (ICRS) implantation in keratoconus patients and highlight the importance of internal astigmatism and its relationship to corneal and refractive astigmatism as prognostic factors. SETTING: Vissum Corporación, Alicante, and Centro de Oftalmología Barrquer, Barcelona, Spain. DESIGN: Retrospective case series. METHODS: Visual, refractive, topographic, and aberrometric variables were evaluated in eyes having ICRS implantation. The eyes were divided into 2 groups according to the relative position of the keratometric axis and refractive axis; that is, coincident axis (0 degree ± 15 [SD]) or uncoincident axis. Internal astigmatism was calculated by vectorial analysis. The relationship between topographic astigmatism and refractive astigmatism was evaluated. The follow-up was 6 months. RESULTS: Of the 127 eyes evaluated, 79 had grade II keratoconus and 48 had grade I keratoconus. Statistically significant differences were found in the relative position of the refractive axis and keratometric axis (P=.017). Internal astigmatism had a significant correlation with the gain in visual acuity in patients with grade II keratoconus (r = -0.455, P=.0001). This relationship was less significant in patients with grade I keratoconus (r = -0.391, P=.021). CONCLUSION: The predictability of visual and refractive outcomes can be significantly increased in grade II keratoconus patients when the relative position of the keratometric and refractive axes; the internal, corneal, and refractive astigmatism; and their combinations are used as prognostic factors. FINANCIAL DISCLOSURE: No author has a financial or proprietary interest in any material or method mentioned.
Authors: Luis Fernández-Vega Cueto; Carlos Lisa; David Madrid-Costa; Jesús Merayo-Lloves; José F Alfonso Journal: J Ophthalmol Date: 2017-08-29 Impact factor: 1.909
Authors: Hussain F Al-Habboubi; Hernan Martinez-Osorio; Azza M Y Maktabi; Abdulrahman H Badawi; Faisal N Aldosari; Rajiv Khandekar; Samar A Al-Swailem Journal: Saudi J Ophthalmol Date: 2022-07-11