Ocular Causes of Visual Distortions
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12 Retina Gabriele K
299 12 Retina Gabriele K. Lang and Gerhard K. Lang 12.1 Basic Knowledge The retina is the innermost of three successive layers of the globe. It comprises two parts: ❖ A photoreceptive part (pars optica retinae), comprising the first nine of the 10 layers listed below. ❖ A nonreceptive part (pars caeca retinae) forming the epithelium of the cil- iary body and iris. The pars optica retinae merges with the pars ceca retinae at the ora serrata. Embryology: The retina develops from a diverticulum of the forebrain (proen- cephalon). Optic vesicles develop which then invaginate to form a double- walled bowl, the optic cup. The outer wall becomes the pigment epithelium, and the inner wall later differentiates into the nine layers of the retina. The retina remains linked to the forebrain throughout life through a structure known as the retinohypothalamic tract. Thickness of the retina (Fig. 12.1) Layers of the retina: Moving inward along the path of incident light, the individual layers of the retina are as follows (Fig. 12.2): 1. Inner limiting membrane (glial cell fibers separating the retina from the vitreous body). 2. Layer of optic nerve fibers (axons of the third neuron). 3. Layer of ganglion cells (cell nuclei of the multipolar ganglion cells of the third neuron; “data acquisition system”). 4. Inner plexiform layer (synapses between the axons of the second neuron and dendrites of the third neuron). 5. Inner nuclear layer (cell nuclei of the bipolar nerve cells of the second neuron, horizontal cells, and amacrine cells). 6. Outer plexiform layer (synapses between the axons of the first neuron and dendrites of the second neuron). -
Localisation of Visual Hallucinations
BRITISH MEDICAL JOURNAL 16 JULY 1977 147 of hypothermia; the duration of cardiac arrest; and the disturbances of sleep or consciousness.4 Hallucinations may be promptness and correctness of treatment. Peterson's pessi- evoked by sensory deprivation, but other factors are usually mistic report from California,8 in which all 15 near-drowned present; thus the "black-patch" delirium that may follow children who had fits, fixed dilated pupils, flaccidity, and loss cataract extraction in the elderly probably results from sensory Br Med J: first published as 10.1136/bmj.2.6080.147 on 16 July 1977. Downloaded from of pain sensation suffered severe anoxic encephalopathy, deprivation and mild senile brain changes and is more frequent may be explained by the high water temperatures there. In when hearing is also impaired.5 warm water the protective effect of hypothermia against brain Hallucinations may be due to focal lesions. Past experiences, damage would be missing. In contrast was the case described the quality of eidetic imagery, and psychodynamic "actors in Trondheim, Norway,9 in which a 5-year-old fell through influence the content of organic hallucinosis,6 and it would be ice in fresh water with an outside temperature of 10° below unwise to lean too heavily on the occurrence and nature of zero centigrade. He was in the water for 22 minutes and was hallucinosis in localising intracranial lesions. Visual hallucina- brought out apparently dead, with widely dilated pupils and tions are a relatively infrequent accompaniment oflesions ofthe bluish white skin. He was warmed up (the method was not calcarine cortex (Brodmann's area 17), which has few thalamo- described) and-despite the risks noted above-was given cortical connections; yet they may occur as a false-localising external cardiac massage without suffering ventricular symptom of frontal or subtentorial lesions. -
Visual Perception in Migraine: a Narrative Review
vision Review Visual Perception in Migraine: A Narrative Review Nouchine Hadjikhani 1,2,* and Maurice Vincent 3 1 Martinos Center for Biomedical Imaging, Massachusetts General Hospital, Harvard Medical School, Boston, MA 02129, USA 2 Gillberg Neuropsychiatry Centre, Sahlgrenska Academy, University of Gothenburg, 41119 Gothenburg, Sweden 3 Eli Lilly and Company, Indianapolis, IN 46285, USA; [email protected] * Correspondence: [email protected]; Tel.: +1-617-724-5625 Abstract: Migraine, the most frequent neurological ailment, affects visual processing during and between attacks. Most visual disturbances associated with migraine can be explained by increased neural hyperexcitability, as suggested by clinical, physiological and neuroimaging evidence. Here, we review how simple (e.g., patterns, color) visual functions can be affected in patients with migraine, describe the different complex manifestations of the so-called Alice in Wonderland Syndrome, and discuss how visual stimuli can trigger migraine attacks. We also reinforce the importance of a thorough, proactive examination of visual function in people with migraine. Keywords: migraine aura; vision; Alice in Wonderland Syndrome 1. Introduction Vision consumes a substantial portion of brain processing in humans. Migraine, the most frequent neurological ailment, affects vision more than any other cerebral function, both during and between attacks. Visual experiences in patients with migraine vary vastly in nature, extent and intensity, suggesting that migraine affects the central nervous system (CNS) anatomically and functionally in many different ways, thereby disrupting Citation: Hadjikhani, N.; Vincent, M. several components of visual processing. Migraine visual symptoms are simple (positive or Visual Perception in Migraine: A Narrative Review. Vision 2021, 5, 20. negative), or complex, which involve larger and more elaborate vision disturbances, such https://doi.org/10.3390/vision5020020 as the perception of fortification spectra and other illusions [1]. -
Transient Monocular Visual Loss
Transient Monocular Visual Loss VALÉRIE BIOUSSE, MD AND JONATHAN D. TROBE, MD ● PURPOSE: To provide a practical update on the diagno- when most episodes of TMVL do not cause total loss of sis and management of transient monocular visual loss vision.2 (TMVL). The most important step in evaluating a patient with ● DESIGN: Perspective. visual loss is to establish whether the visual loss is ● METHODS: Review of the literature. monocular or binocular.2,5 Monocular visual loss always ● RESULTS: TMVL is an important clinical symptom. It results from lesions anterior to the chiasm (the eye or the has numerous causes but most often results from tran- optic nerve), whereas binocular visual loss results from sient retinal ischemia. It may herald permanent visual lesions of both eyes or optic nerves, or, more likely, of the loss or a devastating stroke, and patients with TMVL chiasm or retrochiasmal visual pathway. should be evaluated urgently. A practical approach to the Deciding whether an episode of abrupt visual loss evaluation of the patient with TMVL must be based on occurred in one eye or both is not always easy. Very few the patient’s age and the suspected underlying etiology. patients realize that binocular hemifield (homonymous) In the older patient, tests should be performed to inves- visual field loss affects the fields of both eyes. They will tigate giant cell arteritis, atherosclerotic large vessel usually localize it to the eye that lost its temporal field. The disease, and cardiac abnormalities. In the younger pa- best clues to the fact that visual loss was actually binocular tient, TMVL is usually benign and the evaluation should are reading impairment (monocular visual loss does not be tailored to the particular clinical setting. -
Approved and Unapproved Abbreviations and Symbols For
Facility: Illinois College of Optometry and Illinois Eye Institute Policy: Approved And Unapproved Abbreviations and Symbols for Medical Records Manual: Information Management Effective: January 1999 Revised: March 2009 (M.Butz) Review Dates: March 2003 (V.Conrad) March 2008 (M.Butz) APPROVED AND UNAPPROVED ABBREVIATIONS AND SYMBOLS FOR MEDICAL RECORDS PURPOSE: To establish a database of acceptable ocular and medical abbreviations for patient medical records. To list the abbreviations that are NOT approved for use in patient medical records. POLICY: Following is the list of abbreviations that are NOT approved – never to be used – for use in patient medical records, all orders, and all medication-related documentation that is either hand-written (including free-text computer entry) or pre-printed: DO NOT USE POTENTIAL PROBLEM USE INSTEAD U (unit) Mistaken for “0” (zero), the Write “unit” number “4”, or “cc” IU (international unit) Mistaken for “IV” (intravenous) Write “international unit” or the number 10 (ten). Q.D., QD, q.d., qd (daily) Mistaken for each other Write “daily” Q.O.D., QOD, q.o.d., qod Period after the Q mistaken for Write (“every other day”) (every other day) “I” and the “O” mistaken for “I” Trailing zero (X.0 mg) ** Decimal point is missed. Write X mg Lack of leading zero (.X mg) Decimal point is missed. Write 0.X mg MS Can mean morphine sulfate or Write “morphine sulfate” or magnesium sulfate “magnesium sulfate” MSO4 and MgSO4 Confused for one another Write “morphine sulfate” or “magnesium sulfate” ** Exception: A trailing zero may be used only where required to demonstrate the level of precision of the value being reported, such as for laboratory results, imaging studies that report size of lesions, or catheter/tube sizes. -
Bilateral Rhegmatogenous Retinal Detachment in an Asymptomatic Patient Julie L
Bilateral Rhegmatogenous Retinal Detachment in an Asymptomatic Patient Julie L. Marsh, OD; Heather R. Miller, OD; Renae E. Welke, OD; Andrew Gurwood, OD Retinal detachments occur in approximately 2.8% of patients who have lattice degeneration with holes.1,2 We present a case of bilateral asymptomatic rhegmatogenous retinal detachments successfully repaired with a silicone exoplant encircling buckle, cryotherapy, and barrier laser. I. Case history A 44-year-old African-American male presented with no visual or ocular complaints for an ocular examination to update their spectacle and contact lens prescriptions. The patient denied history of trauma, flashes, floaters, or decreased vision. The patient’s ocular and medical histories were unremarkable. II. Pertinent findings Best-corrected visual acuities measured 20/20 OD and 20/70 OS. Pupils were equal, round, and responsive to light with an afferent pupillary defect noted OS. Brightness and red cap testing were negative. Versions were smooth and full in all positions of gaze. Confrontation visual fields were full to finger counting OD. Confrontation visual field testing OS revealed an 8- degree superior nasal defect, which was confirmed with an Amsler grid. Refractive error was measured with negligible changes at -5.50 – 2.50 X 180 OD and - 7.50 – 3.00 X 180 OS. Slit lamp examination was unremarkable in both eyes. Intraocular pressures measured 14 mmHg OU by Goldmann applanation tonometry. Dilated fundus examination of both eyes revealed lattice degeneration with holes in all quadrants. The left eye demonstrated an inferior temporal retinal tear infiltrated with subretinal fluid creating a rhegmatogenous retinal detachment, extending into the macula. -
Root Eye Dictionary a "Layman's Explanation" of the Eye and Common Eye Problems
Welcome! This is the free PDF version of this book. Feel free to share and e-mail it to your friends. If you find this book useful, please support this project by buying the printed version at Amazon.com. Here is the link: http://www.rooteyedictionary.com/printversion Timothy Root, M.D. Root Eye Dictionary A "Layman's Explanation" of the eye and common eye problems Written and Illustrated by Timothy Root, M.D. www.RootEyeDictionary.com 1 Contents: Introduction The Dictionary, A-Z Extra Stuff - Abbreviations - Other Books by Dr. Root 2 Intro 3 INTRODUCTION Greetings and welcome to the Root Eye Dictionary. Inside these pages you will find an alphabetical listing of common eye diseases and visual problems I treat on a day-to-day basis. Ophthalmology is a field riddled with confusing concepts and nomenclature, so I figured a layman's dictionary might help you "decode" the medical jargon. Hopefully, this explanatory approach helps remove some of the mystery behind eye disease. With this book, you should be able to: 1. Look up any eye "diagnosis" you or your family has been given 2. Know why you are getting eye "tests" 3. Look up the ingredients of your eye drops. As you read any particular topic, you will see that some words are underlined. An underlined word means that I've written another entry for that particular topic. You can flip to that section if you'd like further explanation, though I've attempted to make each entry understandable on its own merit. I'm hoping this approach allows you to learn more about the eye without getting bogged down with minutia .. -
Eleventh Edition
SUPPLEMENT TO April 15, 2009 A JOBSON PUBLICATION www.revoptom.com Eleventh Edition Joseph W. Sowka, O.D., FAAO, Dipl. Andrew S. Gurwood, O.D., FAAO, Dipl. Alan G. Kabat, O.D., FAAO Supported by an unrestricted grant from Alcon, Inc. 001_ro0409_handbook 4/2/09 9:42 AM Page 4 TABLE OF CONTENTS Eyelids & Adnexa Conjunctiva & Sclera Cornea Uvea & Glaucoma Viitreous & Retiina Neuro-Ophthalmic Disease Oculosystemic Disease EYELIDS & ADNEXA VITREOUS & RETINA Blow-Out Fracture................................................ 6 Asteroid Hyalosis ................................................33 Acquired Ptosis ................................................... 7 Retinal Arterial Macroaneurysm............................34 Acquired Entropion ............................................. 9 Retinal Emboli.....................................................36 Verruca & Papilloma............................................11 Hypertensive Retinopathy.....................................37 Idiopathic Juxtafoveal Retinal Telangiectasia...........39 CONJUNCTIVA & SCLERA Ocular Ischemic Syndrome...................................40 Scleral Melt ........................................................13 Retinal Artery Occlusion ......................................42 Giant Papillary Conjunctivitis................................14 Conjunctival Lymphoma .......................................15 NEURO-OPHTHALMIC DISEASE Blue Sclera .........................................................17 Dorsal Midbrain Syndrome ..................................45 -
Internuclear Ophthalmoplegia and Horner's Syndrome Due To
362 Journal of the Royal Society of Medicine Volume 86 June 1993 Internuclear ophthalmoplegia and Her erythrocyte sedimentation rate (ESR) was 105 in the Horner's syndrome due to presumed first hour, the white blood cell count was 11.1 x109/l, giant cell arteritis platelets 475x 109/1, the blood film showed some target cells and ++ rouleaux. Her alkaline phosphatase was 226 and her 7y-glutamine transferase 102. A computerized tomography scan reported atrophic changes in the cerebral hemispheres, and an old infarct was noted in the left temporal lobe. Within Ayman Askari MRCP1 0 M P Jolobe FRCP2 6 days of starting treatment the headache improved remarkably, and in the following 2 months the patient D I Shepherd FRCP2 'Princess Royal Hospital; maintained her progress with no change in the neurological Telford, Shropshire and 2Tameside General Hospital signs. The ESR was 47 within 8 days of admission and 3 by Ashton-under-Lyne, Lancashire day 38 of starting treatment. Keywords: giant cell arteritis; ophthalmoplegia; Horner's syndrome; Discussion ataxic nystagmus Our aim is to draw attention to the association between neuro-ophthalmic signs and presumed GCA. Leukocytosis, abnormal latex fixation test and fever are in keeping with cell arteritis is an inflammatory, the diagnosis. It is likely that many patients with GCA have Giant (GCA) occlusive ophthalmoplegia in the course of their illness and failure arteriopathy of unknown aetiology. It is common in the to detect it may be due to the transient nature of this elderly, with an incidence of 17.4 per 100 000 ofthe popula- manifestation3. -
Adjusting to a Sudden “Aging” of the Lens
Research Article Vol. 33, No. 3 / March 2016 / Journal of the Optical Society of America A A129 Adjusting to a sudden “aging” of the lens 1, 2 1 KATHERINE E. M. TREGILLUS, *JOHN S. WERNER, AND MICHAEL A. WEBSTER 1University of Nevada, Department of Psychology, 1664 N. Virginia Street, Reno, Nevada 89557, USA 2University of California, Department of Ophthalmology & Vision Science, Davis, California 95616, USA *Corresponding author: [email protected] Received 9 October 2015; revised 13 December 2015; accepted 20 December 2015; posted 21 December 2015 (Doc. ID 251656); published 3 February 2016 Color perception is known to remain largely stable across the lifespan despite the pronounced changes in sensi- tivity from factors such as the progressive brunescence of the lens. However, the mechanisms and timescales controlling these compensatory adjustments are still poorly understood. In a series of experiments, we tracked adaptation in observers after introducing a sudden change in lens density by having observers wear glasses with yellow filters that approximated the average spectral transmittance of a 70-year-old lens. Individuals were young adults and wore the glasses for 5 days for 8 h per day while engaged in their normal activities. Achromatic settings were measured on a CRT before and after each daily exposure with the lenses on and off, and were preceded by 5 min of dark adaptation to control for short-term chromatic adaptation. During each day, there was a large shift in the white settings consistent with a partial compensation for the added lens density. However, there was little to no evidence of an afterimage at the end of each daily session, and participants’ perceptual nulls were roughly aligned with the nulls for short-term chromatic adaptation, suggesting a rapid renormalization when the lenses were removed. -
Myopic Macular Degeneration Myopic Macular Degeneration Can Occur in People Who Are Severely Short-Sighted Due to Extreme Elongation of the Eyeball
Myopic Macular Degeneration Myopic macular degeneration can occur in people who are severely short-sighted due to extreme elongation of the eyeball. The stretching of the retina can result in tears in the macula and bleeding beneath the retina. How the eye works Light passes through the cornea at the front of your eye, and is focused by the lens onto your retina. The retina is a delicate tissue that lines the inside of your eye. The retina converts the light into electrical signals that travel along the optic nerve to your brain. The brain interprets these signals to “see” the world around you. Light from the object you are looking at directly is focused onto a tiny area of the retina called the macula at the back of the eye. The macula is about 4mm across and is responsible for detailed central vision and most colour vision. It provides the vision you need to read, recognise faces, drive a car, see colours clearly, and any other activity that requires detailed, fine vision. The rest of the retina gives you side vision (peripheral vision). What is myopia? Myopia, often known as “being short-sighted”, causes vision to be blurry in the distance but clearer when looking at things up close. It is a very common condition of the eyes and, for most people, it can easily be dealt with using contact lenses or glasses which will make vision clear and crisp. Most people have myopia because their eyeball has grown too long or their cornea (the clear window at the front of the eye) is more steeply curved than usual. -
Cranial Nerve Palsies in Spontaneous Carotid Artery Dissection
J7ournal ofNeurology, Neurosurgery, and Psychiatry 1993;56:1191-1199 1 191 J Neurol Neurosurg Psychiatry: first published as 10.1136/jnnp.56.11.1191 on 1 November 1993. Downloaded from Cranial nerve palsies in spontaneous carotid artery dissection Matthias Sturzenegger, P Huber Abstract the reported "idiopathic" jugular foramen Two patients had isolated unilateral cra- (Vernet) and similar syndromes (Villaret, nial nerve palsies due to spontaneous Collet Siccard) in the older literature might internal carotid artery (ICA) dissection well have been caused by spontaneous- carotid without ischaemic cerebral involvement. dissection.5 In those times ICA dissection as a One had acute glossopharyngeal and cause of cranial nerve palsy was poorly vagal, the other isolated hypoglossal known, angiography quite risky, and ultra- nerve palsy. Reviewing all reported cases sound and MRI not available. Out of 31 con- of angiographically confirmed ICA dis- secutive patients with ICA dissection section in the literature, 36 additional diagnosed at our department within four cases with unequivocal ipsilateral cranial years, two presented with cranial nerve palsies nerve palsies were analysed. While an without cerebral involvement. isolated palsy ofthe IXth and Xth has not been reported previously, palsies of the XIIth nerve or the IXth to XIIth nerves Case reports were most frequently found. In these PATEENT 1 patients, lower cranial nerve palsies are A 42-year-old man had been in excellent probably the result of compression by an health. He had no vascular risk factors. After enlarging ICA due to mural haematoma. strenuous activity (cutting wood) in military Symptoms and signs indicative of carotid service he suddenly felt pain in the right dissection were concurrently present upper jaw which later extended to the ear and only in some reported cases.