Purchase this article with an account.
Margarita Montano, Vicente Correa-Gomez, Alejandro Navas, Arturo J. Ramirez-Miranda, Alberto Haber, Ricardo Vargas, Tito Ramírez- Luquín, Enrique O. Graue; Intracorneal Rings For Keratectasia: Is There A Real Difference Between Them?. Invest. Ophthalmol. Vis. Sci. 2012;53(14):4052.
Download citation file:
© ARVO (1962-2015); The Authors (2016-present)
To analyze the effect of age, intracorneal ring type and keratoconus degree on the outcomes of intracorneal ring implantation in patients with corneal ectasia.
Patients with clinical and topographic (Oculus Pentacam) diagnosis of keratoconus or post-LASIK ectasia treated with intrastromal ring segments from 2007 to September 2011. Keratometric values , sphere, cylinder, spherical equivalent, uncorrected and best corrected visual acuity preop and postoperatively were recorded. Non parametric variables were analyzed with Wilcoxon rank test and a linear regression analysis was performed to evaluate the effect of age, ring type and kerataconus degree using STATA v. 10
71 consecutive eyes of 49 patients. Keratoconus as graded with Amsler-Krumeich classification were distributed as follow : type 1 39.4 % ( n= 26 ), type 2 45.5 % (n=30), type 3 12.1% (n=8) and type 4 3% (n=2). Before surgery mean uncorrected visual acuity was logMAR 1.3 0 ± 0.46, mean best spectacle corrected visual acuity was logMAR 0.36± 0.2 and mean astigmatism of 5.02± 2.24 D. Postoperatively uncorrected visual acuity was logMAR 0.62 ± 0.3, best spectacle corrected visual acuity was logMAR 0.29 ± 0.17 and astigmatism 4.32 ± 1.7D. These differences were all statistically significant with p=0.001, p=0.009 and p=0.013, respectively. Multiple linear regression analysis revealed that when adjusting for age, ring segment type and keratoconus degree only the later contributed significantly to the outcome p=0.028
When implanting intracorneal ring segments to improve vision in keratectasia , the most influential and important variable to consider is the keratoconus degree at the time of surgery rather than the type of device being used.
This PDF is available to Subscribers Only