DOCSLIB.ORG

Vision Problems in MULTIPLE SCLEROSIS

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
Vision Problems in MULTIPLE SCLEROSIS Vision Problems IN MULTIPLE SCLEROSIS LIZ DIAGNOSED IN 2002 A vision problem is the first symptom of adapt. Some have even turned vision MS for many people. The sudden onset of problems into advantages. Flo Fox, a double vision, eye pain or blurring can be photographer living with MS in New York terrifying, and the knowledge that vision City, says that her adaptations helped her may be compromised makes people with to become a better photographer, and MS anxious about the future. Fortunately, she has taught other people with vision the prognosis is good for recovery from problems how to use various types of many vision problems associated with MS. cameras adjusted to their abilities. Blindness can occur, but is very rare. This document discusses the main MS- More people are faced with the need related eye problems, but people with MS to accommodate to persistent vision may have other eye problems, just like changes. If vision problems do persist, anyone else. Regular eye care and periodic resulting in permanent low vision, there examinations are important for everyone. are resources and tools to help people Vision Problems | 1 people recover within a month, others MS-Related Vision need up to a year. Most people regain Problems normal or close-to-normal sight. However, the quality of their vision, including Optic neuritis, an inflammation of color or depth perception and contrast the optic nerve, is the most common sensitivity, may be reduced after an episode visual disorder associated with MS. of optic neuritis. Symptoms of optic neuritis include blurred vision, dimming of colors, pain Temporary worsening of vision may also when the eye is moved, blind spots occur after recovery from optic neuritis. and lessening of ability to see contrast Hot showers or baths, exercise, a bout (contrast sensitivity). Double vision of flu, or a fever may all trigger dimmed (diplopia) and involuntary movement of color, blurred vision, and other problems. the eyes (nystagmus) are other common Nerve fibers that are demyelinated problems, both linked to inflammation of (have lost their myelin insulation) or are brain stem areas that control movements remyelinating (under repair) are very of the eye. Diplopia disturbs vision sensitive to higher temperatures. These by producing double images. Because heat- related symptoms resolve when the seeing double can affect a person’s person cools off, be it from ice packs, over- sense of orientation in space, diplopia the-counter fever reducers, cool drinks, may interfere with balance. Nystagmus air conditioning or a soak in a cool tub reduces vision in a number of ways, of water. “The symptoms mean the optic including oscillopsia: an experience of nerve is not conducting information as the world “wiggling.” The wiggling may well as it should,” said Dr. Gregory P. be horizontal or vertical, and may occur Van Stavern, a neuroophthalmologist in one eye, or both. It typically causes at Washington University in St. Louis. impaired vision and, often, loss of balance. “This doesn’t mean a person is having a These three disorders are not linked to new attack of MS. If symptoms persist each other and usually occur separately. for more than a day or so after the body temperature has returned to normal, then Optic Neuritis contact a physician.” Treatment Optic neuritis is a type of MS relapse that affects one or both optic nerves. The In the Optic Neuritis Treatment Trial symptoms of eye pain and blurred vision (ONTT), high-dose intravenous steroids may worsen over the first few days to two were shown to accelerate recovery weeks, and then gradually improve. Some from visual symptoms and to delay Vision Problems | 2 development of MS. Dr. Roy W. Beck, of Texas, Southwestern Medical Center executive director of the Jaeb Center in Dallas, recommends IVIG for people for Health Research in Tampa, Florida, with MS who have diabetes, are manic- who was principal investigator, said depressive, or cannot tolerate steroids for “Intravenous corticosteroids at the time other reasons. of a first episode of acute optic neuritis There is little information on the appear to have a short-term beneficial effectiveness of complementary therapies effect… delaying the time to the for vision problems, but some people development of a second demyelinating report relief from vitamin B-12 shots event, and therefore a diagnosis of during an optic neuritis episode. “We definite MS. However, there did not know optic nerve function depends appear to be a long-term benefit from a on vitamin B-12 and folate,” said Dr. single course of IV steroid treatment.” Thomas R. Hedges, III, professor of The ONTT also found that people ophthalmology and neurology at Tufts treated with oral steroids did not do University School of Medicine and as well as those that had intravenous the director of neuroophthalmology at treatment or were not treated at all. the New England Medical Center. “I Oral steroids apparently increased encourage people to take multivitamins.” the risk of recurrence. According to Dr. Frohman, anyone If the initial symptoms of optic neuritis coming in for a vision problem should are mild, a doctor may decide to allow be screened for vitamin B-12 levels, as a the disorder to resolve on its own. And deficiency can mimic symptoms of MS. the same is true for subsequent episodes Some people with progressive forms of optic neuritis; mild symptoms can be of MS develop persistent optic nerve left untreated while symptoms that are problems, even without having had severe enough to interfere with everyday attacks of optic neuritis. Over the years, activities are generally treated with high- vision may worsen in these individuals, in dose steroids. spite of MS treatment. Intravenous immunoglobulin (IVIG) may be an option for people who are Low-Vision Specialists unable to take steroid medications. While the prospect for recovery from Although a study at the Mayo Clinic had optic neuritis is generally good, there inconclusive results as to the efficacy of are times when vision problems persist. IVIG as a treatment, Dr. Elliot Frohman, Poor vision caused by optic neuritis associate professor of neurology and cannot be helped with eye glasses director of the MS Program at University because the problems are caused by poor Vision Problems | 3 nerve conduction. If problematic vision loss continues, a low-vision specialist Diplopia (Double can analyze your visual function and Vision) and Nystagmus recommend aids and strategies to help you make the most of the vision you have. Double vision may lead to impaired depth Low-vision specialists are licensed doctors perception, imbalance, and difficulty of ophthalmology or optometry. The reading, walking and driving. If double specialist will assess how your eyesight vision occurs as part of an MS relapse, functions in day-to-day living — not just it is likely to resolve spontaneously and how well you do on an eye chart exam. completely. Some people are left with He or she may ask questions about glare, longstanding, permanent double vision contrast, sensitivity to light, and color after incomplete recovery from a relapse. perception. In addition, special charts Progressive MS may also cause persistent may be used to measure other aspects of double vision. your vision. A typical session with a low- When people have nystagmus, they may vision specialist lasts two to three times feel dizzy and unsteady. They may feel longer than a standard eye exam. that the world is moving (oscillopsia) or The low-vision specialist will want as that they are moving abnormally (vertigo). much information as possible — not Nystagmus may occur as a relapse only about your medical and vision symptom or as a chronic symptom of MS history, but your individual needs. If you if recovery from a relapse is incomplete. have an occupational need, a hobby or a It may be a part of progressive MS favorite activity, explain it during your particularly in individuals examination. Your low-vision specialist with poor vision. may be able to prescribe or recommend an optical device, such as microscopic or Treatment telescopic eyewear, a magnifier, a filter Anyone with double vision or nystagmus or a closed circuit television (CCTV) must be evaluated by an ophthalmologist, system, that fits your specific needs. neurologist, or neuro-ophthalmologist, to determine the cause of the double vision. If the double vision or nystagmusare due to a relapse of MS, the relapse may be treated with steroids in order to shorten its duration. Vision Problems | 4 Persistent diplopia may be treated with spectacles with temporary press-on Living with Low Vision (Fresnel) prisms. If the temporary prism If your vision has become permanently is effective for an extended period of impaired, changes in your home and work time, the prism can then be ground in to place can make you more comfortable a new pair of spectacles. and productive. “If there’s misdirection, sometimes we can ∫ Organize your possessions so that they are adjust the muscles surgically to realign easier to find. the eyes. If all else fails, patching — or ∫ Increase your lighting levels, and make sure just applying frosted tape to the inside that important areas, such as your desk, of one eyeglass lens can reduce double dressing area, and stove, are well lit. The vision,” Dr. Hedges said. He emphasizes type of lighting can also make a difference that people with double vision don’t need — experiment to find out what works best for you. to alternate the patch from eye to eye. “Patching an eye will not affect the vision ∫ Eliminate glare by moving mirrors and in any way and will not delay recovery to shiny objects. any significant degree. The brain always ∫ Heighten contrasts using paint or colored tells both eyes to move at once,” he said.
Load more

Recommended publications
  • Hereditary Nystagmus in Early Childhood
    J Med Genet: first published as 10.1136/jmg.7.3.253 on 1 September 1970. Downloaded from Journal of Medical Genetics (1970). 7, 253. Hereditary Nystagmus in Early Childhood BRIAN HARCOURT* Nystagmus is defined as a rhythmic involuntary clinical characteristics of various types of hereditary movement of the eyes, and as an acquired pheno- nystagmus and the techniques which are available menon arising in later childhood or in adult life is to differentiate between 'idiopathic' nystagmus and usually a symptom of serious neurological or laby- nystagmus as a symptom of an occult disorder of the rinthine disease; in such cases the movements of the visual apparatus in early childhood, some descrip- eyes commonly produce subjective symptoms of tion of the modes of inheritance and of the long- objects moving in the visual panorama (oscillopsia). term visual prognosis are given in the various Nystagmus may also be 'congenital', or, more categories of infantile nystagmus which can be so accurately, may first be observed within a few weeks defined. of birth when the infant begins to attempt to fix and to follow visually stimulating targets by means of Character of Nystagmus conjugate movements of the eyes. In such cases, Though it is not usually possible to arrive at the nystagmus may persist throughout life, but even an exact diagnosis of the cause of nystagmus by ob- at a later stage there is always a complete absence of servation of the eye movements alone, a great deal of the symptom of oscillopsia. Nystagmus which useful information can be obtained by such a study.
    [Show full text]
  • Treacher Collins Prize Essay the Significance of Nystagmus
    Eye (1989) 3, 816--832 Treacher Collins Prize Essay The Significance of Nystagmus NICHOLAS EVANS Norwich Introduction combined. The range of forms it takes, and Ophthalmology found the term v!to"[<xy!too, the circumstances in which it occurs, must be like many others, in classical Greece, where it compared and contrasted in order to under­ described the head-nodding of the wined and stand the relationships between nystagmus of somnolent. It first acquired a neuro-ophthal­ different aetiologies. An approach which is mological sense in 1822, when it was used by synthetic as well as analytic identifies those Goodl to describe 'habitual squinting'. Since features which are common to different types then its meaning has been refined, and much and those that are distinctive, and helps has been learned about the circumstances in describe the relationship between eye move­ which the eye oscillates, the components of ment and vision in nystagmus. nystagmus, and its neurophysiological, Nystagmus is not properly a disorder of eye neuroanatomic and neuropathological corre­ movement, but one of steady fixation, in lates. It occurs physiologically and pathologi­ which the relationship between eye and field cally, alone or in conjunction with visual or is unstable. The essential significance of all central nervous system pathology. It takes a types of nystagmus is the disturbance in this variety of different forms, the eyes moving relationship between the sensory and motor about one or more axis, and may be conjugate ends of the visual-oculomotor axis. Optimal or dysjugate. It can be modified to a variable visual performance requires stability of the degree by external (visual, gravitational and image on the retina, and vision is inevitably rotational) and internal (level of awareness affected by nystagmus.
    [Show full text]
  • Macular Dystrophies Mimicking Age-Related Macular Degeneration
    Progress in Retinal and Eye Research 39 (2014) 23e57 Contents lists available at ScienceDirect Progress in Retinal and Eye Research journal homepage: www.elsevier.com/locate/prer Macular dystrophies mimicking age-related macular degeneration Nicole T.M. Saksens a,1,2,7, Monika Fleckenstein b,1,3,7, Steffen Schmitz-Valckenberg b,4,7, Frank G. Holz b,3,7, Anneke I. den Hollander a,5,7, Jan E.E. Keunen a,5,7, Camiel J.F. Boon a,c,d,5,6,7, Carel B. Hoyng a,*,7 a Department of Ophthalmology, Radboud University Medical Centre, Philips van Leydenlaan 15, 6525 EX Nijmegen, The Netherlands b Department of Ophthalmology, University of Bonn, Ernst-Abbe-Str. 2, Bonn, Germany c Oxford Eye Hospital and Nuffield Laboratory of Ophthalmology, John Radcliffe Hospital, University of Oxford, West Wing, Headley Way, Oxford OX3 9DU, United Kingdom d Department of Ophthalmology, Leiden University Medical Centre, Albinusdreef 2, 2333 ZA Leiden, The Netherlands article info abstract Article history: Age-related macular degeneration (AMD) is the leading cause of irreversible blindness in the elderly Available online 28 November 2013 population in the Western world. AMD is a clinically heterogeneous disease presenting with drusen, pigmentary changes, geographic atrophy and/or choroidal neovascularization. Due to its heterogeneous Keywords: presentation, it can be challenging to distinguish AMD from several macular diseases that can mimic the Age-related macular degeneration features of AMD. This clinical overlap may potentially lead to misdiagnosis. In this review, we discuss the AMD characteristics of AMD and the macular dystrophies that can mimic AMD. The appropriate use of clinical Macular dystrophy and genetic analysis can aid the clinician to establish the correct diagnosis, and to provide the patient Differential diagnosis Retina with the appropriate prognostic information.
    [Show full text]
  • Eyelid and Orbital Infections
    27 Eyelid and Orbital Infections Ayub Hakim Department of Ophthalmology, Western Galilee - Nahariya Medical Center, Nahariya, Israel 1. Introduction The major infections of the ocular adnexal and orbital tissues are preseptal cellulitis and orbital cellulitis. They occur more frequently in children than in adults. In Schramm's series of 303 cases of orbital cellulitis, 68% of the patients were younger than 9 years old and only 17% were older than 15 years old. Orbital cellulitis is less common, but more serious than preseptal. Both conditions happen more commonly in the winter months when the incidence of paranasal sinus infections is increased. There are specific causes for each of these types of cellulitis, and each may be associated with serious complications, including vision loss, intracranial infection and death. Studies of orbital cellulitis and its complication report mortality in 1- 2% and vision loss in 3-11%. In contrast, mortality and vision loss are extremely rare in preseptal cellulitis. 1.1 Definitions Preseptal and orbital cellulites are the most common causes of acute orbital inflammation. Preseptal cellulitis is an infection of the soft tissue of the eyelids and periocular region that is localized anterior to the orbital septum outside the bony orbit. Orbital cellulitis ( 3.5 per 100,00 ) is an infection of the soft tissues of the orbit that is localized posterior to the orbital septum and involves the fat and muscles contained within the bony orbit. Both types are normally distinguished clinically by anatomic location. 1.2 Pathophysiology The soft tissues of the eyelids, adnexa and orbit are sterile. Infection usually originates from adjacent non-sterile sites but may also expand hematogenously from distant infected sites when septicemia occurs.
    [Show full text]
  • Understanding Corneal Blindness
    Understanding Corneal Blindness The cornea copes very well with minor injuries or abrasions. If the highly sensitive cornea is scratched, healthy cells slide over quickly and patch the injury before infection occurs and vision is affected. If the scratch penetrates the cornea more deeply, however, the healing process will take longer, at times resulting in greater pain, blurred vision, tearing, redness, and extreme sensitivity to light. These symptoms require professional treatment. Deeper scratches can also cause corneal scarring, resulting in a haze on the cornea that can greatly impair vision. In this case, a corneal transplant may be needed. Corneal Diseases and Disorders that May Require a Transplant Corneal Infections. Sometimes the cornea is damaged after a foreign object has penetrated the tissue, such as from a poke in the eye. At other times, bacteria or fungi from a contaminated contact lens can pass into the cornea. Situations like these can cause painful inflammation and corneal infections called keratitis. These infections can reduce visual clarity, produce corneal discharges, and perhaps erode the cornea. Corneal infections can also lead to corneal scarring, which can impair vision and may require a corneal transplant. Fuchs' Dystrophy. Fuchs' Dystrophy occurs when endothelial cells gradually deteriorate without any apparent reason. As more endothelial cells are lost over the years, the endothelium becomes less efficient at pumping water out of the stroma (the middle layers of the cornea). This causes the cornea to swell and distort vision. Eventually, the epithelium also takes on water, resulting in pain and severe visual impairment. Epithelial swelling damages vision by changing the cornea's normal curvature, and causing a sightimpairing haze to appear in the tissue.
    [Show full text]
  • Department of Ophthalmology Medical Faculty of Padjadjaran University Cicendo Eye Hospital, the National Eye Center Bandung
    1 DEPARTMENT OF OPHTHALMOLOGY MEDICAL FACULTY OF PADJADJARAN UNIVERSITY CICENDO EYE HOSPITAL, THE NATIONAL EYE CENTER BANDUNG Case report : Clinical features and Diagnosis of Neuromyelitis Optica Spectrum Disorder (NMOSD) Presenter : Lucy Nofrida Siburian Supervisor : DR. Bambang Setiohaji, dr., SpM(K)., MH.Kes Has been reviewed and approved by supervisor of neuro-ophthalmology unit DR. Bambang Setiohaji, dr., SpM(K)., MH.Kes Friday, August 04, 2017 07.00 am 2 Abstract Introduction : Neuromyelitis optica spectrum disorder (NMOSD), previously known as Devic’s disease, is an inflammatory CNS syndrome distinct from multiple sclerosis (MS). It is characterized by severe, immune-mediated demyelination and axonal damage predominantly targeting the optic nerves and spinal cord though rarely the brain is also involved. Most patients with NMO and many with NMOSD have autoantibodies against the water channel aquaporin-4(AQP4-Ab), which are thought to be pathogenic. However, some patients are seronegative for AQP4-Abs and the lack of a biomarker makes diagnosis and management of these patients difficult. Aim : To present an NMO case and to know the current diagnosis criteria of NMOSD Case report : A woman, 42 years old, came to neuro-ophthalmology unit of Cicendo eye hospital on March 14, 2017 with sudden blurred vision on the right eye (RE) two days before admission without eye movement pain. Physical examination and body weight were normal. Visual acuity (VA) of the right eye (RE) was 1/300 and the best corrected VA on the left eye was 1.0. Anterior segment on the RE showed relative afferent pupillary defect grade 3 (RAPD), others were normal and so is on the LE.
    [Show full text]
  • Cranial Nerve Palsy
    Cranial Nerve Palsy What is a cranial nerve? Cranial nerves are nerves that lead directly from the brain to parts of our head, face, and trunk. There are 12 pairs of cranial nerves and some are involved in special senses (sight, smell, hearing, taste, feeling) while others control muscles and glands. Which cranial nerves pertain to the eyes? The second cranial nerve is called the optic nerve. It sends visual information from the eye to the brain. The third cranial nerve is called the oculomotor nerve. It is involved with eye movement, eyelid movement, and the function of the pupil and lens inside the eye. The fourth cranial nerve is called the trochlear nerve and the sixth cranial nerve is called the abducens nerve. They each innervate an eye muscle involved in eye movement. The fifth cranial nerve is called the trigeminal nerve. It provides facial touch sensation (including sensation on the eye). What is a cranial nerve palsy? A palsy is a lack of function of a nerve. A cranial nerve palsy may cause a complete or partial weakness or paralysis of the areas served by the affected nerve. In the case of a cranial nerve that has multiple functions (such as the oculomotor nerve), it is possible for a palsy to affect all of the various functions or only some of the functions of that nerve. What are some causes of a cranial nerve palsy? A cranial nerve palsy can occur due to a variety of causes. It can be congenital (present at birth), traumatic, or due to blood vessel disease (hypertension, diabetes, strokes, aneurysms, etc).
    [Show full text]
  • 39Th Annual Meeting
    North American Neuro-Ophthalmology Society 39th Annual Meeting February 9–14, 2013 Snowbird Ski Resort • Snowbird, Utah POSTER PRESENTATIONS Tuesday, February 12, 2013 • 6:00 p.m. – 9:30 p.m. Authors will be standing by their posters during the following hours: Odd-Numbered Posters: 6:45 p.m. – 7:30 p.m. Even-Numbered Posters: 7:30 p.m. – 8:15 p.m. The Tour of Posters has been replaced with Distinguished Posters. The top-rated posters this year are marked with a “*” in the Syllabus and will have a ribbon on their poster board. Poster # Title Presenting Author 1* Redefining Wolfram Syndrome in the Molecular Era Patrick Yu-Wai-Man Management and Outcomes of Idiopathic Intracranial Hypertension with Moderate-Severe 2* Rudrani Banik Visual Field Loss: Pilot Data for the Surgical Idiopathic Intracranial Hypertension Treatment Trial Correlation Between Clinical Parameters And Diffusion-Weighted Magnetic Resonance 3* David M. Salvay Imaging In Idiopathic Intracranial Hypertension 4* Contrast Sensitivity Visual Acuity Defects in the Earliest Stages of Parkinsonism Juliana Matthews 5* Visual Function and Freedom from Disease Activity in a Phase 3 Trial for Relapsing Multiple Sclerosis Laura J. Balcer Dimensions of the Optic Nerve Head Neural Canal Using Enhanced Depth Imaging Optical 6* Kevin Rosenberg Coherence Tomography in Non-Arteritic Ischemic Optic Neuropathy Compared to Normal Subjects Eye Movement Perimetry: Evaluation of Saccadic Latency, Saccadic Amplitude, and Visual 7* Matthew J. Thurtell Threshold to Peripheral Visual Stimuli in Young Compared With Older Adults 9* Advanced MRI of Optic Nerve Drusen: Preliminary Findings Seth A. Smith 10* Clinical Features of OPA1-Related Optic Neuropathy: A Retrospective Case Series Philip M.
    [Show full text]
  • The Pharmacological Treatment of Nystagmus: a Review
    Review The pharmacological treatment of nystagmus: a review Rebecca Jane McLean & Irene Gottlob† Ophthalmology Group, University of Leicester, UK 1. Introduction 2. Acquired nystagmus Nystagmus is an involuntary, to-and-fro movement of the eyes that can result in a reduction in visual acuity and oscillopsia. Mechanisms that cause 3. Infantile nystagmus nystagmus are better understood in some forms, such as acquired periodic 4. Other treatments used in alternating nystagmus, than in others, for example acquired pendular nystagmus nystagmus, for which there is limited knowledge. Effective pharmacological 5. Conclusion treatment exists to reduce nystagmus, particularly in acquired nystagmus 6. Expert opinion and, more recently, infantile nystagmus. However, as there are very few randomized controlled trials in the area, most pharmacological treatment options in nystagmus remain empirical. Keywords: 3,4-diaminopyridine, acquired nystagmus, acquired pendular nystagmus, baclofen, downbeat nystagmus, gabapentin, infantile nystagmus, memantine, multiple sclerosis, periodic alternating nystagmus, upbeat nystagmus Expert Opin. Pharmacother. (2009) 10(11):1805-1816 1. Introduction The involuntary, to-and-fro oscillation of the eyes in pathological nystagmus can occur in the horizontal, vertical and/or torsional plane and be further classified into a jerk or pendular waveform [1]. Nystagmus leads to reduced visual acuity due to the excessive motion of images on the retina, and also the movement of images away from the fovea [2]. As the desired target falls further from the centre of the fovea, receptor density decreases and therefore the ability to perceive detail is reduced [3]. Visual acuity also declines the faster the target moves across the fovea [4]. Three main mechanisms stabilize the line of sight (to static targets) so that the image we see is fixed and clear.
    [Show full text]
  • Orthoptic Department Information Sheet
    Are there any complications? Keratoconus is a rare condition where the cornea becomes thinner and cone shaped. This results in increasingly large amounts of astigmatism resulting in poor vision which is not fully corrected by glasses. Contact numbers Keratoconus usually requires contact lenses Orthoptist: for clear vision, and may eventually result in needing surgery on the cornea. St Richard’s A Keratometer is an instrument sometimes 01243 831499 used to measure the curvature of the cornea. By focusing a circle of light on the Southlands cornea and measuring its reflection, it is 01273 446077 possible to tell the exact curvature of the cornea’s surface. A more sophisticated procedure called corneal topography may be done in some cases to get an even more detailed idea of Orthoptic Department the shape of the cornea. Information Sheet We are committed to making our publications as accessible as possible. If you need this document in an alternative format, for example, large print, Braille or a language other than Astigmatism English, please contact the Communications Office by email: [email protected] St Richard’s Hospital or speak to a member of the department. Spitalfield Lane Chichester West Sussex PO19 6SE www.westernsussexhospitals.nhs.uk Southlands Hospital Department: Orthoptics Upper Shoreham Road Issue date: March 2018 Shoreham-by-Sea Review date: March 2020 West Sussex BN43 6TQ Leaflet Ref: ORT03 This leaflet is intended to answer some of What are the signs and symptoms? These eye drops stop the eyes from the questions of patients or carers of Children are good at adapting to blurred focussing for a few hours so that the patients diagnosed with astigmatism under vision and will often not show any signs of Optometrist can get an accurate reading.
    [Show full text]
  • Contrast Sensitivity Function in Graves' Ophthalmopathy and Dysthyroid Optic Neuropathy Br J Ophthalmol: First Published As 10.1136/Bjo.77.11.709 on 1 November 1993
    Britishjournal ofOphthalmology 1993; 77: 709-712 709 Contrast sensitivity function in Graves' ophthalmopathy and dysthyroid optic neuropathy Br J Ophthalmol: first published as 10.1136/bjo.77.11.709 on 1 November 1993. Downloaded from Maria S A Suttorp-Schulten, Rob Tijssen, Maarten Ph Mourits, Patricia Apkarian Abstract defocus greatly facilitates the process of subjec- Contrast sensitivity function was measured by tive refraction correction, but reduced contrast a computer automated method on 38 eyes with sensitivity at low spatial frequencies may present dysthyroid optic neuropathy and 34 eyes with with normal Snellen acuity. As there are various Graves' ophthalmopathy only. The results degrees ofvisual loss within the group ofpatients were compared with 74 healthy control eyes. with dysthyroid neuropathy, assessment of Disturbances of contrast sensitivity functions spatial vision across the frequency and contrast were found in both groups when compared with spectrum may reveal visual impairment not controls. The eyes affected with dysthyroid readily detected by standard visual acuity optic neuropathy showed pronounced loss of measures. contrast sensitivity in the low frequency range, The contrast sensitivity function has proved a which facilitates differentiation between the useful tool for detecting visual disturbances two groups. when Snellen acuity fails to show comparable (BrJ Ophthalmol 1993; 77: 709-712) dysfunction - for example, in glaucoma,'4 retinal disease,'516 and pterygia." The clinical potential for contrast sensitivity functions has also been Graves' ophthalmopathy is related to thyroid demonstrated in patients with optic neuro- disease and is characterised by oedema and pathies, " 2"02' including dysthyroid optic neuro- infiltration ofthe extraocular muscles and orbital pathy."22 This study compares the contrast tissue.
    [Show full text]
  • Astigmatism Astigmatism Is One of the Most Common Vision Problems, But
    Astigmatism Astigmatism is one of the most common vision problems, but most people don't know what it is. Many people are relieved to learn that astigmatism is not an eye disease. Like nearsightedness and farsightedness, astigmatism is a type of refractive error – a condition related to the shape and size of the eye that causes blurred vision. In addition to blurred vision, uncorrected astigmatism can cause headaches, eyestrain and make objects at all distances appear distorted. Astigmatism signs and symptoms If you have only a small amount of astigmatism, you may not notice it at all, or you may have only mildly blurred or distorted vision. But even small amounts of uncorrected astigmatism can cause headaches, fatigue and eyestrain over time. Astigmatism usually develops in childhood. A study at the Ohio State University School of Optometry found that more than 28% of schoolchildren have astigmatism. Children may be even more unaware of the condition than adults, and they may also be less likely to complain of blurred or distorted vision. But astigmatism can cause problems that interfere with learning, so it's important to have your child’s eyes examined at regular intervals during their school years. What causes astigmatism? Usually, astigmatism is caused by an irregular­shaped cornea, the clear front surface of the eye. In astigmatism, the cornea isn’t perfectly round, but instead is more football­ or egg­shaped. In some cases, astigmatism may be caused by an irregular­shaped lens inside the eye. In most astigmatic eyes, the irregular shape of the cornea or lens causes light rays to form two distorted images in the back of the eye, rather than a single clear one.
    [Show full text]