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Ellen Sy M.,University of California at Los Angeles | Ramirez-Miranda A.,Institute Oftalmologia | Zarei-Ghanavati S.,Mashad University of Medical science | Engle J.,Aurora University | And 2 more authors.
Journal of Refractive Surgery | Year: 2013

PURPOSE: To compare the maximum posterior elevation (MPE) measurements before and after LASIK using a dual rotating Scheimpflug (DRS) imaging system (Galilei, Ziemer Ophthalmic Systems, Port, Switzerland) and a scanning slit-beam (SSB) imaging system (Orbscan IIz, Bausch & Lomb, Rochester, NY). METHODS: This retrospective study included 78 eyes from 78 patients who underwent myopic LASIK. Preoperative and postoperative data collected included anterior and posterior best-fit sphere radius and axial curvature readings, posterior central elevation (PCE), and MPE relative to a best-fit sphere using a 7.8-mm region of interest. Data were compared using paired t test analysis. RESULTS: Mean preoperative PCE (5.06 ± 2.29 μm with the DRS system and 12.78 ± 6.90 μm with the SSB system) and MPE (4.87 ± 4 μm with the DRS system and 15.44 ± 9.78 μm with the SSB system) were statistically different (P < .001). Mean postoperative PCE (4.55 ± 2.34 μm with the DRS system and 20.59 ± 8.11 μm with the SSB system) and MPE (4.90 ± 3.35 μm with the DRS system and 24.95 ± 10.15 μm with the SSB system) were statistically different (P < .001). The difference between preoperative and postoperative MPE measurements by DRS was not statistically significant (P = .953), whereas the difference measured by SSB was statistically significant (P < .001). CONCLUSIONS: The consistency of DRS measurements suggests that the posterior surface of the cornea does not change appreciably after keratorefractive surgery and is imaged more accurately using DRS compared with SSB. The DRS system affords confidence in interpreting data that are useful for discerning morphologic abnormalities of the cornea, both before and after keratorefractive surgery. Copyright © SLACK Incorporated. Source

Palacio C.,Fundacion Hospital Nuestra Senora de la Luz | De Ortega L.F.,Asociacion Para Evitar la Ceguera en Mexico | Bustos F.R.,Antiguo Hospital Civil de Guadalajara Fray Antonio Alcalde | Chavez E.,Institute Oftalmologia | And 2 more authors.
Clinical Ophthalmology | Year: 2016

Purpose: The purpose of this study was to evaluate the aqueous humor bioavailability and clinical efficacy of bromfenac 0.09% vs nepafenac on the presence of cystoid macular edema (CME) after phacoemulsification. Material and methods: A Phase II, double-blind, masked, active-controlled, multicenter, clinical trial of 139 subjects, randomized to either a bromfenac 0.09% ophthalmic solution (n=69) or nepafenac 0.1% (n=70). Subjects instilled a drop three times a day for a period of 30 days. Follow-up visits were on days 2, 7, 15, 30, and 60. Biomicroscopy, clinical ocular signs, and assessment of posterior segment were performed. The primary efficacy endpoints included the presence of CME evaluated by optical coherence tomography. Safety evaluation included intraocular pressure, transaminase enzymes, lissamine green, and fluorescein stain. Results: The demographic and efficacy variables were similar between groups at baseline. The presence of pain, photophobia, conjunctival hyperemia, chemosis, cellularity, and corneal edema disappeared by day 30 in both groups. The central retinal thickness did not show sig­nificant changes after treatment when compared to baseline as follows: in the bromfenac group (247.2±32.9 vs 252.0±24.9 μm; P=0.958) and in nepafenac group (250.8±34 vs 264.0±34.1 μm; P=0.137), respectively. A statistically significant difference was observed between bromfenac and nepafenac group: (252.0±24.9 vs 264.0±34.1 μm; P=0.022), at day 30, respectively; even though there was no clinical relevance in the presentation of CME. There were no significant alterations in intraocular pressure, either lissamine green or fluorescein stains. The adverse events were not related to the interventions. Conclusion: Bromfenac 0.09% ophthalmic solution showed similar clinical efficacy to reduce the presentation of CME after phacoemulsification compared to nepafenac 0.01%. © 2016 Palacio et al. Source

Cardenas J.M.,National Autonomous University of Mexico | Martinez-Perez M.E.,National Autonomous University of Mexico | March F.,Institute Oftalmologia | Hevia-Montiel N.,National Autonomous University of Mexico
Advances in Intelligent Systems and Computing | Year: 2013

Exudates are one of the principal lesion present in the normal development of Diabetic Retinopathy (DR), its detection is an important step in (DR) screening and classification. This paper presents an automated method for bright lesions detection in retinal images by means of the mean shift filtering. Due to uneven illumination of retinal images it is necessary to perform a preprocessing step consisting of a shade correction technique finding non-structures pixels and adjusting a third order polynomial to be substracted from the original image. The mean shift filtering is applied to enhance bright areas and to uniform background non-structures regions. A region growing algorithm is performed from local maxima regions taken as seeds to get the final results. A set of 20 retinal images selected and manually tagged by a retinal specialist ophthalmologist were used for the evaluation. Results present a true positive rate (TPR) of 0.627 and a specificity SPC of 0.979. It is demonstrated that Mean shift filtering is a promising method for exudates detection. © 2013 Springer-Verlag. Source

Tischfield M.A.,Childrens Hospital Boston | Tischfield M.A.,Kirby Neurobiology Center | Tischfield M.A.,The Manton Center for Orphan Disease Research | Tischfield M.A.,Harvard University | And 71 more authors.
Cell | Year: 2010

We report that eight heterozygous missense mutations in TUBB3, encoding the neuron-specific β-tubulin isotype III, result in a spectrum of human nervous system disorders that we now call the TUBB3 syndromes. Each mutation causes the ocular motility disorder CFEOM3, whereas some also result in intellectual and behavioral impairments, facial paralysis, and/or later-onset axonal sensorimotor polyneuropathy. Neuroimaging reveals a spectrum of abnormalities including hypoplasia of oculomotor nerves and dysgenesis of the corpus callosum, anterior commissure, and corticospinal tracts. A knock-in disease mouse model reveals axon guidance defects without evidence of cortical cell migration abnormalities. We show that the disease-associated mutations can impair tubulin heterodimer formation in vitro, although folded mutant heterodimers can still polymerize into microtubules. Modeling each mutation in yeast tubulin demonstrates that all alter dynamic instability whereas a subset disrupts the interaction of microtubules with kinesin motors. These findings demonstrate that normal TUBB3 is required for axon guidance and maintenance in mammals. © 2010 Elsevier Inc. All rights reserved. Source

Hernandez-Bogantes E.,Institute Oftalmologia | Amescua G.,University of Miami | Navas A.,Institute Oftalmologia | Garfias Y.,Institute Oftalmologia | And 4 more authors.
British Journal of Ophthalmology | Year: 2015

We describe a novel surgical technique for pterygium removal taking advantage of the properties of amniotic membrane and limbal epithelial stem cells. A total of 10 eyes underwent pterygium excision with amniotic membrane coverage of the bare sclera and placement of pieces of limbal epithelium in a linear fashion in the affected limbal area covered by a second amniotic membrane using fibrin glue. After up to 8 months of follow-up, there were no signs of early recurrence or sight-threatening complications. The minor ipsilateral simple limbal epithelial transplantation technique for the treatment of pterygium requires less tissue than the conventional conjunctival autograft, leaving healthy conjunctiva if needed for another procedure in the future and offers the advantages of epithelial stem cells, which in the long term may reduce the rate of recurrence significantly. Source

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