Description Module
The Description Module contains narrative descriptions of the clinical trial, including a brief summary and detailed description. These descriptions provide important information about the study's purpose, methodology, and key details in language accessible to both researchers and the general public.
Description Module path is as follows:
Study -> Protocol Section -> Description Module
Description Module
Ignite Creation Date:
2025-12-25 @ 2:24 AM
Ignite Modification Date:
2025-12-25 @ 2:24 AM
NCT ID:
NCT01432834
Brief Summary:
The purpose of the study was to assess the efficacy of the Allegretto Wave excimer laser and the wavefront optimized ablation profile in correcting primarily non-anterior astigmatism faults, following laser in-situ keratomileusis (LASIK) and photorefractive keratectomy (PRK).
Detailed Description:
Different optical components of the eye contribute to the total astigmatism error.In specific, the anterior corneal surface is responsible for the anterior component of astigmatism fault (anterior astigmatism), while the posterior corneal surface and the lens are responsible for the posterior one (posterior astigmatism).
Regarding our study, 74 refractive surgery candidates were recruited. Only one eye from each candidate was randomly enrolled in the study. Of them, 40 eyes underwent LASIK treatment (LG group), while 34 eyes underwent PRK treatment (PG group). The Allegretto Wave excimer laser (software version: 2.020 / WaveLight AG, Erlangen, Germany) was used for the ablation in all groups. Preoperatively, the ocular residual astigmatism (ORA) was calculated for each eye, according to which each astigmatism fault was characterized as primarily anterior or non-anterior.ORA is the vectorial value of astigmatism arising from non-anterior sources. Its amount on total astigmatism (R) is determined by the magnitude ratio ORA/R. Ratios below 1 indicate primarily anterior astigmatism, while ratios above 1 indicate primarily non-anterior astigmatism. 20 LG eyes and 16 PG eyes presented primarily anterior astigmatism (LG-A and PG-A subgroups, respectively), while 20 LG eyes and 18 PG eyes demonstrated primarily non-anterior astigmatism (LG-NA and PG-NA subgroups, respectively). Postoperatively, vector analysis of astigmatism correction was conducted; The following indexes were calculated: a) Correction index (CI), b) Difference vector (DV) and c) Index of Success (IOS).
Study:
NCT01432834
Study Brief:
Protocol Section:
NCT01432834