AIM To construct patient-specific solid models of human cornea from ocular topographer data, to increase the accuracy of the biomechanical and optical estimate of the changes in refractive power and stress caused by photorefractive keratectomy (PRK). METHOD Corneal elevation maps of five human eyes were taken with a rotating Scheimpflug camera combined with a Placido disk before and after ref...

Corneal collagen cross-linking (CXL) is a safe and effective technique for the management of corneal ecstatic disorders. It has been proven that CXL is effectual in stopping the progression of keratoconus quasi ‘freezing’ the cornea and in many cases avoiding corneal transplantation. Nevertheless, patients’ basic problem, which is the deterioration of their vision due to irregular astigmatism, ...

PURPOSE To compare central corneal thickness measurements made using two different methods, optical coherence tomography (OCT) and ultrasound pachymetry, applied both in normal eyes and in eyes on which photorefractive keratectomy (PRK) had been performed. A second objective was to assess the intrasession variability of OCT measurements. METHODS In this prospective study, central corneal thic...

PURPOSE To report the effect of wavefront-guided photorefractive keratectomy and corneal collagen cross-linking (CXL) on visual problems after Ferrara ring segment placement. MATERIALS AND METHODS A 32-year-old male patient was treated with a Ferrara ring segment for keratoconus. One year later, the ring was removed due to severe glare complaints. After 6 months, wavefront-guided photorefract...

PURPOSE To determine predictive factors for intra-operative cyclotorsion in photorefractive keratectomy (PRK). METHODS A retrospective statistical analysis of medical records pertaining to 3,996 eyes undergoing PRK was conducted. Outcome measures of this study were the likely existence of statistically significant relations between diverse and potentially influential factors and the occurrenc...

AIMS/BACKGROUND Since wound healing processes are known to be more rapid in those who are young, it was decided to examine the effect of patient age on refractive outcome of photorefractive keratectomy (PRK). METHODS The records of 599 eyes that had undergone PRK were studied retrospectively. The eyes were categorised by baseline myopia and patient age. Spherical equivalent and corneal haze w...

BACKGROUND To compare the changes in anterior and posterior corneal elevations after combined transepithelial photorefractive keratectomy (PRK) and accelerated corneal collagen cross-linking (CXL) and after PRK. METHODS Medical records of 82 eyes of 44 patients undergoing either combined transepithelial PRK and CXL (PRK-CXL group) or transepithelial PRK (PRK group) were examined retrospective...

This study describes a case of nodular epithelial hyperplasia and stromal alterations in a patient with keratoconus who was submitted to topography-guided photorefractive keratectomy (PRK) followed by corneal collagen cross-linking. Debridement of the epithelial nodule was performed. After a 2-year followup, a new topography-guided PRK was indicated.