Publications by authors named "Juan Alvarez De Toledo"
To build a representative 3D finite element model (FEM) for intracorneal ring segment (ICRS) implantation and to investigate localized optical changes induced by different ICRS geometries, a hyperelastic shell FEM was developed to compare the effect of symmetric and progressive asymmetric ICRS designs in a generic healthy and asymmetric keratoconic (KC) cornea. The resulting deformed geometry was assessed in terms of average curvature via a biconic fit, sagittal curvature (K), and optical aberrations via Zernike polynomials. The sagittal curvature map showed a locally restricted flattening interior to the ring (Kmax -11 to -25 dpt) and, in the KC cornea, an additional local steepening on the opposite half of the cornea (Kmax up to +1.
View Article and Find Full Text PDFBackground: Corneal epithelium remodeling in response to changes in the anterior corneal surface (keratoconus, corneal refractive surgery) is well-documented in the literature. However, several conditions may induce a different behavior of the epithelium, in which focal areas of epithelial thickening induce irregular astigmatism. This case report presents a highly unusual case of irregular astigmatism induced by an epithelial hyperplasia of unknown etiology, which was treated by the mechanical removal of only the epithelium.
View Article and Find Full Text PDFPurpose: To analyze visual and refractive results after wedge resection to correct high astigmatism after penetrating keratoplasty (PK) for keratoconus.
Setting: Cornea Unit of the Centro de Oftalmología Barraquer Barcelona, Spain.
Design: A retrospective quasi-experimental, before and after study.
Purpose: To analyze the anatomical and functional results of Boston type I keratoprosthesis (B1-KPro) as a primary corneal procedure in high-risk (HR) cases and non-high-risk (NHR) cases.
Methods: In this retrospective interventional case series, all patients who underwent B1-KPro at a single center between January 2006 and March 2021 were reviewed and identified. Cases were classified according to the primary diagnosis.
Purpose: To evaluate recurrence and visual outcomes of phototherapeutic keratectomy (PTK) in lattice corneal dystrophy.
Methods: Kaplan-Meier survival analyses were retrospectively performed. Recurrence was defined as central biomicroscopic findings of recurrence with decreased visual acuity: loss of at least two lines or visual acuity ≤ 20/40) at any time during the follow-up.
Purpose: To analyze the clinical outcomes obtained with asymmetric intracorneal corneal ring segments (ICRS) of variable thickness and width in patients with keratoconus, identifying predictive parameters of the final visual outcome.
Methods: This prospective, longitudinal, non-comparative clinical trial enrolled 35 eyes of 27 patients with keratoconus with a significant difference among corneal topographic and comatic axes. All eyes underwent implantation of AJL-pro+ ICRS (AJL Ophthalmic).
To analyze the long-term anatomical survival, functional survival, and complications of Boston type 1 keratoprosthesis (KPro) in the eyes with congenital aniridia-associated keratopathy (AAK). A retrospective review of 12 eyes with congenital aniridia that underwent a Boston type 1 KPro surgery was conducted. A Kaplan-Meier analysis was performed.
View Article and Find Full Text PDFPurpose: To evaluate the local geometric effects of a unilateral intrastromal ring segment with a combined variation of ring thickness and base width in a finite element simulation, and to compare it against the isolated effect of thickness or base width variation alone.
Methods: A two-dimensional finite-element model of a transversely isotropic cornea was created assuming either axisymmetric stress or plane strain condition. The model geometry was composed of a three-layered corneal tissue (epithelium, anterior and posterior stroma) fixed at the limbus.
Purpose: To evaluate the short-term clinical outcomes obtained with a new model of asymmetric intracorneal ring segments (ICRS) with variable thickness and base width in keratoconus.
Setting: Four ophthalmologic centers in Spain.
Design: Prospective multicenter longitudinal noncomparative clinical trial.
Background: To evaluate the anatomical and functional outcomes of autologous contralateral penetrating keratoplasty (autokeratoplasty).
Methods: Kaplan-Meier survival analyses were retrospectively performed. Anatomical failure was defined as regraft or graft permanently cloudy at any time during follow-up.
Purpose: Purpose: To evaluate the long-term stability of scleral-sutured intraocular lenses (IOLs) and analyse the possible causes of suture breakage.
Setting: Barraquer Institute in Barcelona, Spain.
Design: Retrospective study of consecutive cases.
Purpose: To report the diagnosis, histological findings, and treatment of a patient who developed epithelial ingrowth after Descemet membrane endothelial keratoplasty (DMEK).
Methods: We present the case of a type 2 diabetic 60-year-old man who underwent DMEK for Fuchs dystrophy. Two months after surgery, an epithelial ingrowth in the graft-host interface was suspected.
Purpose: To compare anatomical and functional results between three types of keratoprosthesis (KPro) in chemical injury and autoimmune disease.
Methods: 70 clinically comparable cases were included as follows: Boston KPro Type 1 25 eyes, osteo-odonto-keratoprosthesis (OOKP) 23 eyes, Tibial bone KPro 22 eyes. Survival times for anatomical and functional success were evaluated with Kaplan-Meier estimations and Log-rank tests.
Purpose: To present a new technique for treating Lisch epithelial corneal dystrophy (LECD) in cases of recurrence of the disease.
Methods: We present a single case report of a 41-year-old man who presented to the cornea clinic with progressive loss of vision in the right eye. Slit-lamp examination showed a large white-gray whorl-like epithelial opacity connected to the limbus, which spread over the visual axis, affecting visual acuity.
Introduction: The purpose of this study was to report the first case of acute bacterial keratitis produced by methicillin-resistant Staphylococcus aureus after the implantation of two intracorneal ring segments during an uneventful procedure for treating keratoconus in a 13-year-old child.
Case Report: A patient with grade III keratoconus underwent an implantation of intracorneal ring segments with no complications during the procedure. Three days later, a whitish corneal infiltrate appeared in between the union of both corneal rings.
Purpose: To compare ocular surface characteristics in eyes after femtosecond laser-assisted laser in situ keratomileusis (LASIK) or photorefractive keratectomy (PRK).
Setting: Centro de Oftalmologia Barraquer, Barcelona, Spain.
Design: Prospective comparative observational study.
Purpose: To evaluate the corneal button of primary penetrating keratoplasty of patients diagnosed with congenital aniridia. The study took place at the Instituto Universitario Barraquer and the Centro de Oftalmología Barraquer.
Methods: A retrospective analysis of cases diagnosed with congenital aniridia was carried out.
Purpose: The etiology of keratoconus (KC) and the factors governing its progression are not well understood. It has been suggested that this disease might be caused by biochemical alterations in the cornea; changes in the expression profiles of human aqueous humor (hAH) proteins have been observed in some diseases. To gain a new insight into the molecular mechanisms of KC pathology, we examined the hAH proteomes of those in the advanced stages of this disease.
View Article and Find Full Text PDFPurpose: To evaluate the in vivo biocompatibility of grafts composed of sheets of decellularized human corneal stroma with or without the recellularization of human adipose derived adult stem cells (h-ADASC) into the rabbit cornea.
Methods: Sheets of human corneal stroma of 90 μm thickness were decellularized, and their lack of cytotoxicity was assayed. The recellularization was achieved by the injection of 2 × 10(5) labeled h-ADASC in the graft followed by five days of cell culture.
Purpose: To analyse how primary diagnosis and complications affect the evolution of post-operative visual acuity (VA).
Methods: We performed retrospective chart analysis on 59 eyes in 57 patients with various diagnoses, most of which were non-standard indications for Boston type 1 keratoprosthesis (Kpro) implantation. The follow-up period was at least 3 months.
Purpose: To describe the outcome of patients with Boston type 1 keratoprosthesis, with regard to anatomical and visual success.
Methods: Retrospective case series of patients who underwent Boston type I keratoprosthesis surgery at the Centro de Oftalmología Barraquer in Barcelona and at the University Eye Clinic in Salzburg between May 2006 and December 2011. Sixty-seven eyes were included.
Purpose: To report the long-term functional and anatomic outcomes of osteo-odonto-keratoprosthesis and tibial bone keratoprosthesis; to analyze the influence of clinical factors, such as surgical technique, primary diagnosis, age, and postoperative complications, on the final outcome.
Design: Retrospective cohort study.
Methods: setting: Centro de Oftalmología Barraquer, between 1974 and 2005.
Purpose: To determine the main causes of intrastromal corneal ring segment (ICRS) explantation and the relationship with the microscopic findings on the ICRS surface.
Setting: Vissum Corporation-Instituto Oftalmológico de Alicante, Alicante, Spain.
Methods: This study evaluated ICRS that were explanted in centers in Spain from 2000 to 2008.