ABSTRACT The accuracy of the intraocular lens calculation is not perfect, and postoperative refractive errors are common, especially in patients who have undergone previous refractive surgery or in presence of asymmetric corneas. Corneal power after refractive surgery can be more accurately measured using the total optical power map in the 4-mm central zone, by means of Orbscan II or equivalent keratometric reading map available on pentacam, with central measurements of 1.0, 2.0, 3.0 and 4.5 mm. The purpose of this […]

ABSTRACT Objective: To assess sensitivity of corneal volume, corneal asphericity, and D index in early diagnosis of keratoconus. Methods: A cross-sectional analytical study, carried out between December 2018 and October 2020, which analyzed the medical records of 39 patients (78 eyes) diagnosed as keratoconus by a single corneal specialist, using the criteria of Belin-Ambrosio Enhanced Ectasia Display. The collected data were anterior asphericity, posterior asphericity, D index and its parameters (Da, Db, Dt, Dp and Df). The data were entered […]

Abstract Objective: To Perform a review on the diagnosis of keratoconus, focusing on the available propaedeutic methods. Methods: A search was performed in the PubMed database using the key words: Keratoconus, diagnosis, topography and tomography. As it is a review, there was no restriction regarding the publication period of the selected articles. Furthermore, both the preferred practice pattern(PPP) manual of the American Academy of Ophthalmology, as well as the website “eyewiki.aao.org” were used as reference. The project was submitted to […]

Objective: In the presence of an irregular cornea, like in keratoconus, the corneal epithelium has a different profile “masking” the irregular corneal stroma surface. Topographical analysis without considering the epithelium effect can result in an incorrect assessment, affecting the accuracy of any topography guided treatment. The aim of this study was to evaluate the “masking” effect of the corneal epithelium on corneal curvature in patients with keratoconus, comparing topographical findings before and after removal of the epithelium during Crosslinking (CXL). […]

Pellucid marginal corneal degeneration (PMCD) is a rare bilateral noninflammatory ectatic peripheral corneal disorder, usually involving the inferior portion of the cornea, separated from limbus by an area of normal corneal thickness. There is protrusion of the cornea above the thinning area, resulting in high irregular astigmatism. Corneal Topography shows the characteristic, but not pathognomonic, image of a “butterfly wing”. A patient with superior PMCD – an atypical presentation of the disease – is presented, highlighting the importance of the […]

A degeneração marginal pelúcida (DMP) é uma ectasia corneana de difícil manejo em casos moderados e avançados. O transplante de córnea penetrante nesses pacientes deve ser evitado ao máximo tendo em vista que a descentração necessária do botão aumenta o risco de vascularização e consequentemente rejeição, além das dificuldades técnicas e possibilidade de deiscência de sutura devido ao afinamento corneano pronunciado característico desta ectasia. Nós relatamos o caso de uma paciente de 30 anos com DMP com queixa de baixa […]

Introduction: Pterygium is a centripetal proliferation of fibrovascular tissue, which proceeds from the bulbar conjunctiva towards the center of the cornea. Excision of the pterygium may cause visual acuity improvement and surgical excision aims to achieve a topographically regular ocular surface. The improvement of the visual acuity results from the alteration of the refractive corneal power, that is measured in the topography as alteration of the topographic astigmatism. The objective of this study was to evaluate the variation of the […]

Pellucid marginal degeneration (PMD) treatment can be challenging in moderate to advanced cases and penetrating keratoplasty should be avoided due to high risk of complications, such as graft rejection. We report a case of a 30-year-old female patient with PMD that was referred to our service with bilateral low visual acuity, worse in her right eye and contact lenses intolerance. We performed a corneal crescentic lamellar wedge resection that resulted in good useful vision and postponed the keratoplasty for eighteen […]