Search results for "Intraocular"

Endothelial cells loss to the hyperopic pacients during phacoemulsification

2018

Introduction The phacoemulsification cataract surgery is the most frequently performed surgery and it generally improves vision in over 90% of the patients. Hyperopic patients are a challenge during phacoemulsification especially because of their short eyeball and shallow anterior chamber. A shallow anterior chamber is associated with overall reduction of the safe zone, which may lead to difficulty in creating the corneal incisions, harder capsulorhexis performing, or endothelial complications. Purpose The aim of the study was to present the endothelial cells loss after the phacoemulsification procedure in the hyperopic patients. Material and methods A number of 1775 patients operated in th…

Optical solutions for the human eye with progressive loss of accommodation. Effect of the pupil.

2016

La presbicia se define como una reducción lenta, natural, irreversible, y relacionada con la edad de la máxima amplitud de acomodación, suficiente como para causar síntomas de borrosidad y astenopia en visión próxima. Afortunadamente, se han desarrollado varios sistemas ópticos que mejoran esta sintomatología y ayudan a recuperar las capacidades visuales para trabajar en visión próxima. Por otro lado, el análisis in-vitro permite obtener resultados objetivos de los sistemas ópticos y así ampliar el conocimiento del rendimiento óptico de estos sistemas. La presente tesis doctoral estudia la calidad óptica in-vitro de lentes de contacto e intraoculares. Se utilizaron dos sistemas in-vitro par…

Does the renin-angiotensin system also regulate intra-ocular pressure?

2009

The renin-angiotensin-aldosterone system is known to play an essential role in controlling sodium balance and body fluid volumes, and thus blood pressure. In addition to the circulating system which regulates urgent cardiovascular responses, a tissue-localized renin-angiotensin system (RAS) regulates long-term changes in various organs. Many recognized RAS components have also been identified in the human eye. The highly vasoconstrictive angiotensin II (Ang II) is considered the key peptide in the circulatory RAS. However, the ultimate effect of RAS activation at tissue level is more complex, being based not only on the biological activity of Ang II but also on the activities of other produ…

Determining postoperative anterior chamber depth

2003

Abstract Purpose: To compare measured and calculated postoperative anterior chamber depths (ACDs). Setting: Department of Ophthalmology and Institute of Medical Physics, University of Vienna, Vienna, Austria, and Department of Ophthalmology, University of Mainz, Mainz, Germany. Methods: The postoperative ACD was measured in 189 pseudophakic eyes using a laboratory prototype of partial coherence interferometry (PCI). In 6 intraocular lens (IOL) groups, the mean ACD was calculated by ray tracing based on the best-known A-constants of the SRK formulas. In addition, for each IOL type, each measured ACD was compared with a value calculated using the individual spherical equivalent of the postope…

Comparison of biometric measurements using partial coherence interferometry and applanation ultrasound

2003

Abstract Purpose To compare and contrast axial length (AL) measurements assessed by ultrasound biometry and optical biometry. Setting Department of Ophthalmology, Johannes Gutenberg-University, Mainz, Germany. Methods Optical biometry and ultrasound biometry were performed in 360 eyes to measure AL. Results In eyes with a clear-appearing crystalline lens, there was a statistically significant median difference in AL measurements between the 2 methods in eyes with a normal or long length. In eyes with cataract, there was a statistically significant median difference in AL measurements in eyes with a normal or short length. In these cases, optical biometry produced larger readings than ultras…

Bacterial Contamination of Anterior Chamber Fluid Following Non-complicated Cataract Surgery

1993

Objective: To study the anterior chamber contamination during non-complicated cataract surgery and its relationship with normal conjuctival organisms. Setting: Ophthalmology Department, La Fe Hospital, University of Valencia. Patients: Forty patients who had undergone cataract extraction using either ECCE, phacoemulsification or nucleus fracture methods. Results: Positive cultures of aqueous humour were obtained in 32.5% of cases. The most commonly isolated organism was Staphylococcus coagulase-negative. Only in 7.7% of cases was the microorganism found in the conjunctiva the same as that found in the anterior chamber. The inoculum size ranged between 20 and 160 colonies/ml. One of the case…

Implantable collamer lens with central hole: 3-year follow-up.

2018

Luis Fernández-Vega-Cueto,1 Carlos Lisa,1 José J Esteve-Taboada,2 Robert Montés-Micó,2 José F Alfonso1,3 1Department of Surgery, Fernández-Vega Ophthalmological Institute, Oviedo, Spain; 2Department of Optics and Optometry and Visual Sciences, University of Valencia, Valencia, Spain; 3School of Medicine, University of Oviedo, Oviedo, Spain Purpose: To evaluate the long-term predictability, stability, safety, and efficacy of the V4c Visian implantable collamer lens (ICL) with central hole to correct myopia.Patients and methods: One hundred and eighty-four eyes of 92 patients were evaluated during 3 years after implantation of …

2017

Purpose To compare two surgical approaches for treating encapsulated blebs after trabeculectomy with mitomycin C, in terms of the development of intraocular pressure and progression of glaucoma in a long-term follow up: 1. bleb needling alone vs. 2. a combined approach of needling with additional transconjunctival scleral flap sutures, to prevent early ocular hypotony. Methods Forty-six patients with failing blebs after trabeculectomy with mitomycin C were enrolled in this study. Patients received either needling revision alone (group 1; n = 23) or a combined needling with additional transconjuctival flap sutures, if intraoperatively the intraocular pressure was estimated to be low (group 2…

Histopathologic Findings in Early Encapsulated Blebs of Young Patients Treated With the Ahmed Glaucoma Valve

2010

Objective/aim Uncontrolled glaucoma presents a challenge for the ophthalmic surgeon especially in children and juvenile patients. For many patients who have undergone failed surgical procedures before, episcleral implants remain the last choice. Encapsulated blebs forming over antiglaucoma devices present a complication leading to malfunctioning or even failure with reincrease in intraocular pressure. We report our histopathologic findings of such blebs developing around the Ahmed glaucoma valve (AGV) after a short time period in young patients. Materials and methods Nine young patients (2 to 17 y of age) with otherwise uncontrollable glaucoma were treated with AGV (models FP-7 and FP-8, si…

Assessment of environmental AMD risk factors in a population of patients suffering from stroke and myocardial infarction

2010

International audience; Purpose: Stroke and myocardial infarction are common diseases occurring in patients suffering from Age Macular Degeneration (AMD). We assessed the rate of AMD and AMD risk factors in patients suffering from recent stroke or myocardial infarction. Methods: Patients suffering from a recent stroke or myocardial infarction (less than 1 month) benefited from a thorough ophthalmic examination with the following measurements and evaluations: visual acuity, intraocular pressure, fundus photography, Raman spectroscopy and macular OCT. In the same time a food questionnaire was dispensed. Finally, blood samples to measure fatty acids and lutein were performed. Results: 74 patie…