Natural history and predictors for progression in pediatric keratoconus.

We studied the demographic and clinical predictors associated with keratoconus progression in a pediatric population. Retrospective cohort study. We evaluated 305 eyes without previous surgeries from 168 patients, 9 to < 18 years old, and with a minimum 36-month follow-up in a hospital corneal ambulatory.

Ultraviolet radiation and the human eye.

This work is a critical review of the current understanding of the effect of ultraviolet radiation on the eye. It deals with the classification of this radiation, environmental level, and the factors that determine it, along with penetration into the human eye, toxicity to ocular structures, associated morbidities, events that may increase the vulnerability of the eye, and artificial eye filters.

Prescription for astigmatic ametropia revisited.

The approach to any refractive condition of the eye with regular astigmatism is more complicated than that for myopia or hyperopia alone. It requires familiarity with the complex images collectively identified as Sturm's conoid. Fortunately, only three of those play a critical role in the interpretation of ametropia with astigmatism.

Correlation between pathogenic species and clinical findings, disease severity, and visual outcome in patients with fungal keratitis.

Purpose: To determine whether a correlation exists between pathogenic species and clinical findings, disease severity, and visual outcome in patients with keratitis and fungal growth in microbiological culture.

Methods: A retrospective study of patients with fungal growth in the microbiological culture of corneal scrapings. Patients were treated at an ophthalmologic reference center in Southeastern Brazil from January 1992 to October 2015.

Eye bank procedures: donor selection criteria.

Eye banks use sterile procedures to manipulate the eye, antiseptic measures for ocular surface decontamination, and rigorous criteria for donor selection to minimize the possibility of disease transmission due to corneal grafting. Donor selection focuses on analysis of medical records and specific post-mortem serological tests. To guide and standardize procedures, eye bank associations and government agencies provide lists of absolute and relative contraindications for use of the tissue based on donor health history.

In vivo ultrathin Descemet stripping automated endothelial keratoplasty with a low-energy and high-frequency femtosecond laser.

This case report describes the production of an ultrathin endothelial donor corneal lamella using a femtosecond laser with low energy and a high frequency. In addition, we report its use in vivo in an eye with pseudophakic bullous keratopathy. The outcomes were observed 3 months after surgery in terms of the change in endothelial donor lamella and full cornea thickness (including pachymetric mapping), visual acuity, and endothelial cell count.

Autoradiographic study on the regenerative capability of the epithelium lining the center of the cornea after multiple debridements of its peripheral region.

Background: The epithelium lining the center of the cornea is assumed to lack stem cells.The purpose is to investigate by autoradiography the regenerative capability of the epithelium lining the central region of the rabbit cornea following seven scrapings of its peripheral lining, during several months.

Methods: After marking the center of the cornea with a 6 mm-diameter trephine, the epithelium outside this area was scraped until reaching the corneoscleral zone.

Regeneration of the corneal epithelium after debridement of its central region: an autoradiographic study on rabbits.

Purpose: To investigate the proliferative behavior of the corneal and limbal epithelia after debridement on the central region of the rabbit cornea.

Methods: After scraping a circular epithelial area, 5 mm in diameter, in the center of the cornea, ([3]) H-thymidine ( ([3]) H-TdR) was injected intravitreally, and the rabbits killed from 1 to 49 days afterward. The cornea, together with the adjacent conjunctiva, was processed for autoradiography.

Epidemiologic aspects and clinical outcome of fungal keratitis in southeastern Brazil.

Purpose: Fungal keratitis (FK) is a sight-threatening disease, more prevalent in developing regions. The present retrospective study was conducted in order to evaluate the epidemiologic and clinical aspects and the progression of FK in patients treated at two ophthalmologic reference centers in Southeast Brazil.

Methods: The charts of patients with infectious keratitis treated between 2000 and 2004 were reviewed.

Bilateral Acanthamoeba ulcer in a user of disposable soft contact lenses: a tragic incident or a consequence of the aggressive policy of soft contact lens trading?

This is the report of a case of bilateral Acanthamoeba keratitis in a 19-year-old woman who bought a pair of disposable soft contact lenses in a boutique. She wore this same pair of lenses for 3 months daily without the appropriate care. This led to bilateral corneal transplantation with cataract extraction and also trabeculectomy in the right eye.

Proliferation of the vascular endothelium of the iris following total debridement of the corneal epithelium and limbal excision of rabbits.

Background: Damage to the corneal epithelium causes not only a reaction for its repair but also affects other parts of the cornea as well as different components of the anterior segment of the eye. The purpose of this investigation was to analyze the consequences, following epithelial and limbal damage, to the iris of rabbits (Oryctolagus cuniculus).

Methods: The corneal epithelium was thoroughly scraped followed by surgical excision of the limbus.

Morphological and autoradiographic studies on the corneal and limbal epithelium of rabbits.

The investigation was centered on the morphological features of the conjunctiva-cornea transition (limbus) of the rabbit eye and the proliferative behavior of its epithelium. The eyes were processed for examination with light and electron microscopy, as well as for autoradiography after intravitreal injection of [(3)H]thymidine ([(3)H]TdR). At the sites of extraocular muscle insertion, the vascularization of the stroma extended to the peripheral cornea, and the limbal epithelium was thin with its basal stratum made up by clear cuboidal cells.

Optical projection mires for measurements of the radii of curvature of the cornea in biomicroscopes.

Keratometry is currently achieved by projecting a circular mire onto the patient's cornea and analyzing the size and shape of its reflected image. The projection mires are decisive for the precision of the measurement. We have previously developed a keratometric module for slit lamps, and the development of four projection mires are presented.

Corneal transplantation in a developing country: problems associated with technology transfer from rich to poor societies.

Purpose: To evaluate the results of penetrating corneal transplantation at a university hospital in Brazil.

Methods: A prospective cohort study was conducted on 146 patients who underwent penetrating keratoplasty at the University Hospital, Faculty of Medicine of Ribeirão Preto, University of São Paulo, Brazil. The participants were followed postoperatively for 36 months or until graft failure.

[MALKS: specifications and development].

Purpose: To describe the characteristics of a new artificial anterior chamber (MALKS, Loktal, São Paulo, Brazil).

Methods: Characteristics analysis and description of a new artificial anterior chamber MALKS (Micro automated lamellar keratoplasty system).

Results: MALKS is composed of eight parts: a) artificial chamber; b) cornea's fix ring; c) nut to join the cornea's fix ring; d) rail and adjuster of lamellar diameter; e) flatteners, to pre-determine lamellar diameter; f) infusion system, that allows the digital objective peroperative control of the intracameral pressure; g) automated microkeratome, and h) marker.