Evolution of Indications for Presbyopia- Correcting Iols
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WSPOS Worldwide Webinar 16: Amblyopia - How and When
Answers to Audience Questions - WSPOS Worldwide Webinar 16: Amblyopia - How and When WWW 16 Panellists Anna Horwood Celeste Mansilla David Granet Krista Kelly Lionel Kowal Susan Cotter Yair Morad Anna Horwood (AH), Celeste Mansilla (CM), Krista Kelly (KK), Lionel Kowal (LK), Susan Cotter (SC), Yair Morad (YM) 1. How do you maintain attained iso visual acuity after successful amblyopia treatment? AH: Intermittent monitoring. If they have regressed previously, I might carry on very intermittent occlusion (an hour or two a week) until I was sure it was stable. CM: With gradual and controlled reduction of the treatment, for example: if the patient had 1 hour of patch per day, I leave it with 1 hour 3 times a week during a month. I do a check and if the visual acuity was maintained, I lower patches to 2 times a week. I keep checking and going down like this until I suspend the treatment. If at any time I detect worsening visual acuity, I return to the previous treatment. SC: Best way is attainment of normal binocular vision. I do not worry about ansiometropic amblyopes who have random dot stereopsis post-treatment. If have constant unilateral strabismus, I can do some limited part-time patching, decreasing patching dosage over time given no regression of VA. YM: repeat examination every 6 months. If I see regression, I will prescribe patching for 30 min a day. 2. How do you plan for very dense amblyopes? AH: I very rarely see them because, with screening, they are picked up early and usually do well. -
Hyperopia Hyperopia
Hyperopia Hyperopia hyperopia hyperopia • Farsightedness, or hyperopia, • Farsightedness occurs if your eyeball is too as it is medically termed, is a short or the cornea has too little curvature, so vision condition in which distant objects are usually light entering your eye is not focused correctly. seen clearly, but close ones do • Its effect varies greatly, depending on the not come into proper focus. magnitude of hyperopia, the age of the individual, • Approximately 25% of the the status of the accommodative and general population is hyperopic (a person having hyperopia). convergence system, and the demands placed on the visual system. By Judith Lee and Gretchyn Bailey; reviewed by Dr. Vance Thompson; Flash illustration by Stephen Bagi 1. Cornea is too flap. hyperopia • In theory, hyperopia is the inability to focus and see the close objects clearly, but in practice many young hyperopics can compensate the weakness of their focusing ability by excessive use of the accommodation functions of their eyes. Hyperopia is a refractive error in • But older hyperopics are not as lucky as them. By which parallel rays of light aging, accommodation range diminishes and for 2. Axial is too short. entering the eye reach a focal older hyperopics seeing close objects becomes point behind the plane of the retina, while accommodation an impossible mission. is maintained in a state of relaxation. 1 Amplitude of Accommodation hyperopia Maximum Amplitude= 25-0.4(age) • An emmetropic eye for reading and other near Probable Amplitude= 18.5-.3(age) work, at distance of 16 in (40cm), the required amount of acc. -
Strabismus, Amblyopia & Leukocoria
Strabismus, Amblyopia & Leukocoria [ Color index: Important | Notes: F1, F2 | Extra ] EDITING FILE Objectives: ➢ Not given. Done by: Jwaher Alharbi, Farrah Mendoza. Revised by: Rawan Aldhuwayhi Resources: Slides + Notes + 434 team. NOTE: F1& F2 doctors are different, the doctor who gave F2 said she is in the exam committee so focus on her notes Amblyopia ● Definition Decrease in visual acuity of one eye without the presence of an organic cause that explains that decrease in visual acuity. He never complaints of anything and his family never noticed any abnormalities ● Incidence The most common cause of visual loss under 20 years of life (2-4% of the general population) ● How? Cortical ignorance of one eye. This will end up having a lazy eye ● binocular vision It is achieved by the use of the two eyes together so that separate and slightly dissimilar images arising in each eye are appreciated as a single image by the process of fusion. It’s importance 1. Stereopsis 2. Larger field If there is no coordination between the two eyes the person will have double vision and confusion so as a compensatory mechanism for double vision the brain will cause suppression. The visual pathway is a plastic system that continues to develop during childhood until around 6-9 years of age. During this time, the wiring between the retina and visual cortex is still developing. Any visual problem during this critical period, such as a refractive error or strabismus can mess up this developmental wiring, resulting in permanent visual loss that can't be fixed by any corrective means when they are older Why fusion may fail ? 1. -
Defining Emmetropia and Ametropia As a Function of Ocular Biometry II
SyntEyes: a Higher Order Statistical Eye Model for Healthy Eyes Jos J. Rozema,*† MSc PhD, Pablo Rodriguez,‡ MSc PhD, Rafael Navarro,‡ MSc PhD, Marie-José Tassignon*†, MD PhD *Dept. of Ophthalmology, Antwerp University Hospital, Edegem, Belgium † Dept. of Medicine and Health Sciences, Antwerp University, Wilrijk, Belgium ‡ICMA, Consejo Superior de Investigaciones Científicas-Universidad de Zaragoza, Facultad de Ciencias, Zaragoza, Spain Abstract Purpose: To present a stochastic eye model that simulates the higher order shape parameters of the eye, as well as their variability and mutual correlations. Methods: The biometry of 312 right eyes of 312 subjects were measured with an autorefractometer, a Scheimpflug camera, an optical biometer and a ray tracing aberrometer. The corneal shape parameters were exported as Zernike coefficients, which were converted into eigenvectors in order to reduce the dimensionality of the model. These remaining 18 parameters were modeled by fitting a sum of two multivariate Gaussians. Based on this fit an unlimited number of synthetic data sets (‘SyntEyes’) can be generated with the same distribution as the original data. After converting the eigenvectors back to the Zernike coefficients, the data may be introduced into ray tracing software. Results: The mean values of nearly all SyntEyes parameters was statistically equal to those of the original data (two one-side t test). The variability of the SyntEyes parameters was the same as for the original data for the most important shape parameters and intraocular distances, but showed significantly lower variability for the higher order shape parameters (F test) due to the eigenvector compression. The same was seen for the correlations between higher order shape parameters. -
PRESBYOND Laser Blended Vision Practical Guide
PRESBYOND Laser Blended Vision Practical Guide Disclaimer: This practical guide was produced independently by Dan Z Reinstein, MD MA(Cantab) FRCSC DABO FRCOphth FEBO1, 2, 3, 4 Glenn I Carp, MBBCh, FC Ophth (SA)1 Timothy J Archer, MA(Oxon), DipCompSci(Cantab)1, 4 Sharon Ritchie, BSc (Hons), MCOptom1 1 London Vision Clinic, London, UK 2 Department of Ophthalmology, Columbia University Medical Center, NY, USA 3 Centre Hospitalier National d’Ophtalmologie, Paris, France 4 Biomedical Science Research Institute, University of Ulster, Coleraine, Northern Ireland Financial Disclosure: Dr Reinstein is a consultant for Carl Zeiss Meditec (Carl Zeiss Meditec AG, Jena, Germany) and has a proprietary interest in the Artemis technology (ArcScan Inc, Golden, Colorado) through patents administered by the Center for Technology Licensing at Cornell University (CTL), Ithaca, New York. Dr Carp receives travel expenses from Carl Zeiss Meditec. The remaining authors have no proprietary or financial interest in the materials presented herein. Preoperative 1. Pre-operative testing protocol 2. Manifest refraction 3. Dominance testing 4. Laser Blended Vision tolerance assessment 5. What myopic target to expect 6. Laser Blended Vision explanation and patient counselling Postoperative 7. Postoperative evaluation 8. Postoperative visual course 9. Cross-blur management at final outcome 10. Appendix A – Preoperative tolerance test examples 11. Appendix B – Postoperative cross-blur and enhancement examples 2 1. Pre-operative testing protocol Highlighted topics are particularly relevant for PRESBYOND • History. Motivation for surgery, previous ocular • Cirrus OCT corneal and epithelial pachymetry. history (including detailed history of contact lens wear, • Undilated WASCA aberrometry. period of wear, type of lens, wear modality, last worn, • Ocular Response Analyser. -
Posterior Vitreous Detachment As Observed by Wide-Angle OCT Imaging
Posterior Vitreous Detachment as Observed by Wide-Angle OCT Imaging Mayuka Tsukahara, OD,1,* Keiko Mori, MD,1 Peter L. Gehlbach, MD, PhD,2 Keisuke Mori, MD, PhD1,3,4,* Purpose: Posterior vitreous detachment (PVD) plays an important role in vitreoretinal interface disorders. Historically, observations of PVD using OCT have been limited to the macular region. The purpose of this study is to image the wide-angle vitreoretinal interface after PVD in normal subjects using montaged OCT images. Design: An observational cross-sectional study. Participants: A total of 144 healthy eyes of 98 normal subjects aged 21 to 95 years (51.4Æ22.0 [mean Æ standard deviation]). Methods: Montaged images of horizontal and vertical OCT scans through the fovea were obtained in each subject. Main Outcome Measures: Montaged OCT images. Results: By using wide-angle OCT, we imaged the vitreoretinal interface from the macula to the periphery. PVD was classified into 5 stages: stage 0, no PVD (2 eyes, both aged 21 years); stage 1, peripheral PVD limited to paramacular to peripheral zones (88 eyes, mean age 38.9Æ16.2 years, mean Æ standard deviation); stage 2, perifoveal PVD extending to the periphery (12 eyes, mean age 67.9Æ8.4 years); stage 3, peripapillary PVD with persistent vitreopapillary adhesion alone (7 eyes, mean age 70.9Æ11.9 years); stage 4, complete PVD (35 eyes, mean age 75.1Æ10.1 years). All stage 1 PVDs (100%) were observed in the paramacular to peripheral region where the vitreous gel adheres directly to the cortical vitreous and retinal surface. After progression to stage 2 PVD, the area of PVD extends posteriorly to the perifovea and anteriorly to the periphery. -
Amblyopia HANDOUT ACES
AMBLYOPIA CORNEA PUPIL CATARACT IRIS LENS RETINA MACULA OPTIC NERVE The eye on the right is at risk for all three types of AMBLYOPIA. Rays of light enter the normal eye on the left, are bent by the cornea and the lens and are focused one the most precise part of the retina called the macula. Light entering the right eye is disrupted by a congenital cataract (deprivational amblyopia). Since the right eye is shorter than the left, light doesn't focus on the retina due to unequal far-sightedness(refractive amblyopia). Since the left eye is crossed (esotropia-type strabismus), incoming light fails to align on the macula (strabismic amblyopia). ye doctors and orthoptists want each child to grow frequently suppresses or "turns off" the brain image from up with the healthiest visual system possible. the non-dominant eye. Strabismic amblyopia can be E This goal requires the close cooperation of treated by combinations of drops, glasses, patching parents, pediatricians, primary doctors, optometrists, and/or eye muscle surgery. school nurses and health aids and the professionals who DETECTION: Within the first days after birth, deal with visually impaired babies. part of each baby's first physical exam is the "red reflex" an abnormality of which could indicate cataract or tumor. At birth, a normal infant has relatively poor vision in the range A part of routine pre-school pediatric check-ups is of 20/2000! Under normal conditions, the visual system improves so that observations of red reflex by photoscreen and Brückner 20/20 vision might be attained by school age and retained after age 10 years. -
Clinical Findings and Management of Posterior Vitreous Detachment
American Academy of Optometry: Case Report 5 Clinical Findings and Management of Posterior Vitreous Detachment Candidate’s Name, O.D. Candidate’s Address Candidate’s Phone number Candidate’s email Abstract: A posterior vitreous detachment is a degenerative process associated with aging that affects the vitreous when the posterior vitreous cortex separates from the internal limiting membrane of the retina. The composition of the vitreous gel can degenerate two collective ways, including synchysis or liquefaction, and syneresis or shrinking. Commonly, this process of separation occurs with the posterior hyaloid resulting in a Weiss ring overlying the optic nerve. Complications of a posterior vitreous detachment may include retinal breaks or detachments, retinal or vitreous hemorrhages, or vitreomacular traction. This case presentation summarizes the etiology of this ocular condition as well as treatment and management approaches. Key Words: Posterior Vitreous Detachment, Weiss Ring, Vitreous Degeneration, Scleral Depression, Nd:YAG Laser 1 Introduction The vitreous humor encompasses the posterior segment of the eye and fills approximately three quarters of the ocular space.1 The vitreous is a transparent, hydrophilic, “gel-like” substance that is described as a dilute solution of collagen, and hyaluronic acid.2,3,4 It is composed of 98% to 99.7% water.4 As the eye matures, changes may occur regarding the structure and composition of the vitreous. The vitreous functions to provide support to the retina against the choroid, to store nutrients and metabolites for the retina and lens, to protect the retinal tissue by acting as a “shock absorber,” to transmit and refract light, and to help regulate eye growth during fetal development.3,4 Case Report Initial Visit (03/23/2018) A 59-year-old Asian female presented as a new patient for examination with a complaint of a new onset of floaters and flashes of light in her right eye. -
Refractive Errors a Closer Look
2011-2012 refractive errors a closer look WHAT ARE REFRACTIVE ERRORS? WHAT ARE THE DIFFERENT TYPES OF REFRACTIVE ERRORS? In order for our eyes to be able to see, light rays must be bent or refracted by the cornea and the lens MYOPIA (NEARSIGHTEDNESS) so they can focus on the retina, the layer of light- sensitive cells lining the back of the eye. A myopic eye is longer than normal or has a cornea that is too steep. As a result, light rays focus in front of The retina receives the picture formed by these light the retina instead of on it. Close objects look clear but rays and sends the image to the brain through the distant objects appear blurred. optic nerve. Myopia is inherited and is often discovered in children A refractive error means that due to its shape, your when they are between ages eight and 12 years old. eye doesn’t refract the light properly, so the image you During the teenage years, when the body grows see is blurred. Although refractive errors are called rapidly, myopia may become worse. Between the eye disorders, they are not diseases. ages of 20 and 40, there is usually little change. If the myopia is mild, it is called low myopia. Severe myopia is known as high myopia. Lens Retina Cornea Lens Retina Cornea Light rays Light is focused onto the retina Light rays Light is focused In a normal eye, the cornea and lens focus light rays on in front of the retina the retina. In myopia, the eye is too long or the cornea is too steep. -
Perspectives on Presbyopia
PERSPECTIVES ON PRESBYOPIA EXTRA CONTENT FOUR PATIENTS AVAILABLE FIVE EXPERTS BY MARY WADE, CONTRIBUTING WRITER ew presbyopia treatments, such as the corneal inlays Kamra and Raindrop, are slowly wending their way through the U.S. Food and Drug Administration approval process. Entirely new approaches to intraocular lenses (IOLs) are in development internationally. Meanwhile,N patients arrive in your office daily, seeking better vision without reading glasses. What are the best treatments to offer them right now? EyeNet asked five leading refractive surgeons to review four hypothetical patients with pres- byopia or pre-presbyopia. The differing recommendations made by these clinicians illustrate the range of valid approaches. The surgeons emphasize that, in all cases, it’s critical to conduct a thorough assessment, talk with patients about their vision priorities, discuss the pros and cons of various approaches, and mention the option of “watchful waiting”—that is, forgoing treatment for the time being. When patients are considering corrective surgery, one of the surgeon’s most important tasks is to help them form realistic expectations regarding visual outcomes and possible complications. (See “Counseling Caveats.”) For those patients who choose to pursue vision correction surgery, the perspectives presented by these refractive experts can help to guide treatment choices with today’s technologies. BONNIE A. HENDERSON, MD KEVIN M. MILLER, MD J. BRADLEY RANDLEMAN, MD STEVEN I. ROSENFELD, MD, FACS SONIA H. YOO, MD ALFRED T. KAMAJIAN T. ALFRED eyenet 37 eventually need cataract surgery, prior refractive surgery may make accurate refraction difficult and constrain lens choices. It makes sense to leave the corneas pristine in older patients. -
Human Amblyopia
Human Amblyopia • “Lazy Eye” • Relatively common developmental visual disorder (~2%) • Reduced visual acuity in an otherwise healthy and properly corrected eye • Associated with interruption of normal early visual experience • Most common cause of vision loss in children • Well characterized behaviorally, not neurologically • Treated by patching in children Visual Deficits in Amblyopia • Reduced monoc. visual acuity - defining feature – Usually 20/30 - 20/60 • Impaired contrast sensitivity – Prominent at high spatial frequencies Contrast Sensitivity Sensitivity Contrast – Central visual field is generally most affected Spatial Frequency • Moderate deficits in object segmentation/recognition and spatial localization • Severe deficits in binocular interactions Subtypes of Amblyopia • Anisometropic – Unequal refractive error between the two eyes • Strabismic – Deviated eye that may or may not have unbalanced refraction • Deprivation – Congenital cataract; corneal opacity; eyelid masses Mechanisms of Amblyopia 1. Form deprivation . Sharp image is not formed at the retina 2. Abnormal binocular vision . Binocularity is often changed or lost in amblyopia Models of Amblyopia • Competition hypothesis originated with experiments in kittens in the 1960s by Hubel and Wiesel • Monocular deprivation of retinal input during ‘critical’ developmental periods leads to striking abnormalities in the physiology of visual cortical neurons • Binocular deprivation actually leads to less severe abnormalities • Amblyopia may be a form of activity-dependent deprivation, -
Review of the Impact of Presbyopia on Quality of Life in the Developing and Developed World
Acta Ophthalmologica 2014 Review Article Review of the impact of presbyopia on quality of life in the developing and developed world Ariana D. Goertz,1 William C. Stewart,2 William R. Burns,3 Jeanette A. Stewart2 and Lindsay A. Nelson2 1University of Nevada, Las Vegas, Nevada, USA 2PRN Pharmaceutical Research Network, LLC, Cheyenne, Wyoming, USA 3Encore Vision, Inc., Fort Worth, Texas, USA ABSTRACT. (Barbero 2013). Everyone eventually Purpose: To examine the public health impact of presbyopia regarding its effect develops presbyopia but symptoms on quality of life (QoL) and society in both the developed and developing worlds. may vary. The major risk factor for Methods: A database was created from articles found on PubMed, the Cochrane presbyopia is age although the condi- Library and Science Direct using the following search terms: presbyopia, QoL, tion may be affected by other factors accommodation, impact, cost, prevention, treatment and public health. Articles including disease, trauma and medica- were accepted into the database if they addressed presbyopia and public health. tions (American Optometric Associa- Results: This study showed in the developed world presbyopic subjects treated tion 2010). with reading glasses suffered a reduction in QoL parameters compared with Presbyopia is classically believed to those who were younger and emmetropic. A small minority of subjects were result from hardening of the lens although other causes have been assessed to be a candidate for additional non-spectacle treatment measures. In described as well such as changes in undeveloped areas, the manifestations of presbyopia were similar to the tissue elasticity and the ciliary body developed world in symptoms, age and reduced QoL.