Flight of Colours' in Lesions of the Visual System'
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Cory Newman Thesis 5-2021 Signed.Pdf (1.303Mb)
DocuSign Envelope ID: 4851A328-CF63-4770-A833-B4246E7E5D23 Simulating Homonymous Hemianopsia for the Care Team by Cory Newman May 2021 Presented to the Division of Science, Information Arts, and Technologies University of Baltimore In Partial Fulfillment of the Requirements for the Degree of Master of Science 5/25/2021 Approved by: ________________________________ [name, Thesis Advisor] ________________________________5/25/2021 [name, Committee Member] i DocuSign Envelope ID: 4851A328-CF63-4770-A833-B4246E7E5D23 Abstract Homonymous hemianopsia is a visual impairment that involves the bilateral loss of a complete visual field. While research has been done to ascertain the details of cause and prognosis of homonymous hemianopsia, an obvious disparity arose in the research on how to educate the supporting care team of a person with homonymous hemianopsia to maximize the creation of educational and rehabilitation plans. This research presents two studies focused on closing that gap by providing an alternative method of understanding. In the initial study 16 participants with a confirmed caregiver relationship to one or more persons with homonymous hemianopsia were surveyed on their personal knowledge of the visual impairment. These participants were asked to express any visual obstacles they have encountered, and to ascertain the availability of a device or program that could provide an interactive interpretation of how their homonymous hemianopsia patient views their surroundings. Survey results confirmed the need for a program that could easily simulate homonymous hemianopsia for the care provider. An additional usability study was completed by eight of the 16 previous participants on a mobile homonymous hemianopsia simulation application prototype. User tests showed that participants gained a significant increase in understanding of how those with a homonymous hemianopsia visual impairment view the environment. -
URGENT/EMERGENT When to Refer Financial Disclosure
URGENT/EMERGENT When to Refer Financial Disclosure Speaker, Amy Eston, M.D. has a financial interest/agreement or affiliation with Lansing Ophthalmology, where she is employed as a ophthalmologist. 58 yr old WF with 6 month history of decreased vision left eye. Ache behind the left eye for 2-3 months. Using husband’s contact lens solution made it feel better. Seen by two eye care professionals. Given glasses & told eye exam was normal. No past ocular history Medical history of depression Takes only aspirin and vitamins 20/20 OD 20/30 OS Eye Pressure 15 OD 16 OS – normal Dilated fundus exam & slit lamp were normal Pupillary exam was normal Extraocular movements were full Confrontation visual fields were full No red desaturation Color vision was slightly decreased but the same in both eyes Amsler grid testing was normal OCT disc – OD normal OS slight decreased RNFL OCT of the macula was normal Most common diagnoses: Dry Eye Optic Neuritis Treatment - copious amount of artificial tears. Return to recheck refraction Visual field testing Visual Field testing - Small defect in the right eye Large nasal defect in the left eye Visual Field - Right Hemianopsia. MRI which showed a subacute parietal and occipital lobe infarct. ANISOCORIA Size of the Pupil Constrictor muscles innervated by the Parasympathetic system & Dilating muscles innervated by the Sympathetic system The Sympathetic System Begins in the hypothalamus, travels through the brainstem. Then through the upper chest, up through the neck and to the eye. The Sympathetic System innervates Mueller’s muscle which helps to elevate the upper eyelid. -
Homonymous Hemianopsia
Source: CLEVELAND CLINIC OHIO USA FACTSHEET Homonymous Hemianopsia Homonymous hemianopsia is a condition in which a person sees only one side - right or left of the visual world of each eye; results from a problem in brain function rather than a disorder of the eyes themselves. This can happen after a head or brain injury. What is homonymous hemianopsia? Homonymous hemianopsia is a condition in which a person sees only one side―right or left―of the visual world of each eye. The person may not be aware that the vision loss is happening in both eyes, not just one. Under normal circumstances, the left half of the brain processes visual information from both eyes about the right side of the world. The right side of the brain processes visual information from both eyes about the left side of the world. A visual world of someone with normal vision A visual world of someone with homonymous hemianopsia In homonymous hemianopsia, an injury to the left part of the brain results in the loss of the right half of the visual world of each eye. An injury to the right part of the brain produces loss of the left side of the visual world of each eye. This condition is created by a problem in brain function rather than a disorder of the eyes themselves. What causes homonymous hemianopsia? The most common cause of this type of vision loss is stroke. However, any disorder that affects the brain—including tumours, inflammation, and injuries--can be a cause. Source: CLEVELAND CLINIC OHIO USA It is estimated that 70% of the injuries leading to hemianopsias are due to an obstruction (blockage) of the blood supply (stroke). -
Oct Institute
Low Vision, Visual Dysfunction and TBI – Treatment, Considerations, Adaptations Andrea Hubbard, OTD, OTR/L, LDE Objectives • In this course, participants will: 1. Learn about interventions involving specialized equipment to adapt an environment for clients with low vision. 2. Learn about the most typical low vision presentations/conditions. 3. Gain increased knowledge of eye anatomy and the visual pathway. Overview of TBI Reference: Centers for Disease Control and Prevention Overview of TBI Risk Factors for TBI Among non-fatal TBI-related injuries for 2006–2010: • Men had higher rates of TBI hospitalizations and ED visits than women. • Hospitalization rates were highest among persons aged 65 years and older. • Rates of ED visits were highest for children aged 0-4 years. • Falls were the leading cause of TBI-related ED visits for all but one age group. – Assaults were the leading cause of TBI-related ED visits for persons 15 to 24 years of age. • The leading cause of TBI-related hospitalizations varied by age: – Falls were the leading cause among children ages 0-14 and adults 45 years and older. – Motor vehicle crashes were the leading cause of hospitalizations for adolescents and persons ages 15-44 years. Reference: Centers for Disease Control and Prevention Overview of TBI Risk Factors for TBI Among TBI-related deaths in 2006–2010: • Men were nearly three times as likely to die as women. • Rates were highest for persons 65 years and older. • The leading cause of TBI-related death varied by age. – Falls were the leading cause of death for persons 65 years or older. -
Neuroanatomy Crash Course
Neuroanatomy Crash Course Jens Vikse ∙ Bendik Myhre ∙ Danielle Mellis Nilsson ∙ Karoline Hanevik Illustrated by: Peder Olai Skjeflo Holman Second edition October 2015 The autonomic nervous system ● Division of the autonomic nervous system …………....……………………………..………….…………... 2 ● Effects of parasympathetic and sympathetic stimulation…………………………...……...……………….. 2 ● Parasympathetic ganglia ……………………………………………………………...…………....………….. 4 Cranial nerves ● Cranial nerve reflexes ………………………………………………………………….…………..…………... 7 ● Olfactory nerve (CN I) ………………………………………………………………….…………..…………... 7 ● Optic nerve (CN II) ……………………………………………………………………..…………...………….. 7 ● Pupillary light reflex …………………………………………………………………….…………...………….. 7 ● Visual field defects ……………………………………………...................................…………..………….. 8 ● Eye dynamics …………………………………………………………………………...…………...………….. 8 ● Oculomotor nerve (CN III) ……………………………………………………………...…………..………….. 9 ● Trochlear nerve (CN IV) ………………………………………………………………..…………..………….. 9 ● Trigeminal nerve (CN V) ……………………………………………………................…………..………….. 9 ● Abducens nerve (CN VI) ………………………………………………………………..…………..………….. 9 ● Facial nerve (CN VII) …………………………………………………………………...…………..………….. 10 ● Vestibulocochlear nerve (CN VIII) …………………………………………………….…………...…………. 10 ● Glossopharyngeal nerve (CN IX) …………………………………………….……….…………...………….. 10 ● Vagus nerve (CN X) …………………………………………………………..………..…………...………….. 10 ● Accessory nerve (CN XI) ……………………………………………………...………..…………..………….. 11 ● Hypoglossal nerve (CN XII) …………………………………………………..………..…………...…………. -
Visual Dysfunction in Optic Chiasm Syndrome an Atomy
1 4/12/2019 Optic chiasm, most important Arrangement of visual fibers Characteristic of visual field VISUAL DYSFUNCTION Bitemporal defects: IN OPTIC CHIASM SYNDROME Superior Inferior Complete Peripheral, central M.HIDAYAT FACULTY OF MEDICINE, A N DALAS UNIVERSITY /M .DJAMIL HOSPITAL PADANG AN ATOMY OF CHIASM OPTIC CHIASM Width : 12 mm 53% fiber from nasal retina crossed to opposite — Length : 8 mmfantero posterior) contra lateral. ■ Inclined : 45 0 Inferior nasal fibers cross anterior loop in to contra lateral (Willbrand's knee) Location : anterior hypothalamus & anterior third Macular fiber cross posterosuperior ventricle 10 mm above sella Vascular supply: Anterior communicating artery Anterior cerebri artery Circle of Willis ANTERIOR ANGLE OF CHIASM Compression to anterior angle of chiasm Small lesion damages the crossing fibers of ipsilaferal eye -> field defect: monocular and temporal Damage of macular crossed fibers: monocular, temporal defects and parasentral scotoma Damage fiber from nasal contralateral, anterior extension : central ipsilateral scotoma and contralateral upper temporal quadrant {"Willbrand’s Knee") 1 4/12/2019 Chiasmal compression from below defects stereotyped pattern : bitemporal defect Example: pituitary adenoma Peripheral fiber damage, defects begin from superior quadrants of both eyes Can be not similar Similar defects causes from tubercullum sellae, meningioma, craniopharyngiomas, aneurysm t Sella or supra sella lesion : damage superior fiber defect bitemporal inferior Bitemporal Hemianopsia Example: angioma -
Structural Brain Abnormalities in Patients with Primary Open-Angle Glaucoma: a Study with 3T MR Imaging
Glaucoma Structural Brain Abnormalities in Patients with Primary Open-Angle Glaucoma: A Study with 3T MR Imaging Wei W. Chen,1–3 Ningli Wang,1,3 Suping Cai,3,4 Zhijia Fang,5 Man Yu,2 Qizhu Wu,5 Li Tang,2 Bo Guo,2 Yuliang Feng,2 Jost B. Jonas,6 Xiaoming Chen,2 Xuyang Liu,3,4 and Qiyong Gong5 PURPOSE. We examined changes of the central nervous system CONCLUSIONS. In patients with POAG, three-dimensional MRI in patients with advanced primary open-angle glaucoma revealed widespread abnormalities in the central nervous (POAG). system beyond the visual cortex. (Invest Ophthalmol Vis Sci. 2013;54:545–554) DOI:10.1167/iovs.12-9893 METHODS. The clinical observational study included 15 patients with bilateral advanced POAG and 15 healthy normal control subjects, matched for age and sex with the study group. Retinal rimary open angle glaucoma (POAG) has been defined nerve fiber layer (RNFL) thickness was measured by optical formerly by intraocular morphologic changes, such as coherence tomography (OCT). Using a 3-dimensional magne- P progressive retinal ganglion cell loss and defects in the retinal tization-prepared rapid gradient-echo sequence (3D–MP-RAGE) nerve fiber layer (RNFL), and by corresponding psychophysical of magnetic resonance imaging (MRI) and optimized voxel- abnormalities, such as visual field loss.1 Recent studies by based morphometry (VBM), we measured the cross-sectional various researchers, however, have suggested that the entire area of the optic nerve and optic chiasm, and the gray matter visual pathway may be involved in glaucoma.2–23 Findings from volume of the brain. -
Central Serous Choroidopathy
Br J Ophthalmol: first published as 10.1136/bjo.66.4.240 on 1 April 1982. Downloaded from British Journal ofOphthalmology, 1982, 66, 240-241 Visual disturbances during pregnancy caused by central serous choroidopathy J. R. M. CRUYSBERG AND A. F. DEUTMAN From the Institute of Ophthalmology, University of Nijmegen, Nijmegen, The Netherlands SUMMARY Three patients had during pregnancy visual disturbances caused by central serous choroidopathy. One of them had a central scotoma in her first and second pregnancy. The 2 other patients had a central scotoma in their first pregnancy. Symptoms disappeared spontaneously after delivery. Except for the ocular abnormalities the pregnancies were without complications. The complaints can be misinterpreted as pregnancy-related optic neuritis or compressive optic neuropathy, but careful biomicroscopy of the ocular fundus should avoid superfluous diagnostic and therapeutic measures. Central serous choroidopathy (previously called lamp biomicroscopy of the fundus with a Goldmann central serous retinopathy) is a spontaneous serous contact lens showed a serous detachment of the detachment of the sensory retina due to focal leakage neurosensory retina in the macular region of the from the choriocapillaris, causing serous fluid affected left eye. Fluorescein angiography was not accumulation between the retina and pigment performed because of pregnancy. In her first epithelium. This benign disorder occurs in healthy pregnancy the patient had consulted an ophthal- adults between 20 and 45 years of age, who present mologist on 13 June 1977 for exactly the same with symptoms of diminished visual acuity, relative symptoms, which had disappeared spontaneously http://bjo.bmj.com/ central scotoma, metamorphopsia, and micropsia. after delivery. -
Asymmetries of Dark and Bright Negative Afterimages Are Paralleled by Subcortical on and OFF Poststimulus Responses
1984 • The Journal of Neuroscience, February 22, 2017 • 37(8):1984–1996 Systems/Circuits Asymmetries of Dark and Bright Negative Afterimages Are Paralleled by Subcortical ON and OFF Poststimulus Responses X Hui Li,1,2 X Xu Liu,1,2 X Ian M. Andolina,1 Xiaohong Li,1 Yiliang Lu,1 Lothar Spillmann,3 and Wei Wang1 1Institute of Neuroscience, State Key Laboratory of Neuroscience, Key Laboratory of Primate Neurobiology, Center for Excellence in Brain Science and Intelligence Technology, Chinese Academy of Sciences, Shanghai 200031, China, 2University of Chinese Academy of Sciences, Shanghai 200031, China, and 3Department of Neurology, University of Freiburg, 79085 Freiburg, Germany Humans are more sensitive to luminance decrements than increments, as evidenced by lower thresholds and shorter latencies for dark stimuli. This asymmetry is consistent with results of neurophysiological recordings in dorsal lateral geniculate nucleus (dLGN) and primary visual cortex (V1) of cat and monkey. Specifically, V1 population responses demonstrate that darks elicit higher levels of activation than brights, and the latency of OFF responses in dLGN and V1 is shorter than that of ON responses. The removal of a dark or bright disc often generates the perception of a negative afterimage, and here we ask whether there also exist asymmetries for negative afterimages elicited by dark and bright discs. If so, do the poststimulus responses of subcortical ON and OFF cells parallel such afterimage asymmetries? To test these hypotheses, we performed psychophysical experiments in humans and single-cell/S-potential recordings in cat dLGN. Psychophysically, we found that bright afterimages elicited by luminance decrements are stronger and last longer than dark afterimages elicited by luminance increments of equal sizes. -
Embryology, Anatomy, and Physiology of the Afferent Visual Pathway
CHAPTER 1 Embryology, Anatomy, and Physiology of the Afferent Visual Pathway Joseph F. Rizzo III RETINA Physiology Embryology of the Eye and Retina Blood Supply Basic Anatomy and Physiology POSTGENICULATE VISUAL SENSORY PATHWAYS Overview of Retinal Outflow: Parallel Pathways Embryology OPTIC NERVE Anatomy of the Optic Radiations Embryology Blood Supply General Anatomy CORTICAL VISUAL AREAS Optic Nerve Blood Supply Cortical Area V1 Optic Nerve Sheaths Cortical Area V2 Optic Nerve Axons Cortical Areas V3 and V3A OPTIC CHIASM Dorsal and Ventral Visual Streams Embryology Cortical Area V5 Gross Anatomy of the Chiasm and Perichiasmal Region Cortical Area V4 Organization of Nerve Fibers within the Optic Chiasm Area TE Blood Supply Cortical Area V6 OPTIC TRACT OTHER CEREBRAL AREASCONTRIBUTING TO VISUAL LATERAL GENICULATE NUCLEUSPERCEPTION Anatomic and Functional Organization The brain devotes more cells and connections to vision lular, magnocellular, and koniocellular pathways—each of than any other sense or motor function. This chapter presents which contributes to visual processing at the primary visual an overview of the development, anatomy, and physiology cortex. Beyond the primary visual cortex, two streams of of this extremely complex but fascinating system. Of neces- information flow develop: the dorsal stream, primarily for sity, the subject matter is greatly abridged, although special detection of where objects are and for motion perception, attention is given to principles that relate to clinical neuro- and the ventral stream, primarily for detection of what ophthalmology. objects are (including their color, depth, and form). At Light initiates a cascade of cellular responses in the retina every level of the visual system, however, information that begins as a slow, graded response of the photoreceptors among these ‘‘parallel’’ pathways is shared by intercellular, and transforms into a volley of coordinated action potentials thalamic-cortical, and intercortical connections. -
Eye Essentials 5
continuing education 33 Eye essentials 5 Successful participation in each Classification and localisation module of this approved series counts as one credit towards the GOC CET scheme administered by Vantage and of visual field defects one towards the AOI’s scheme. In the last of our features based on the Eye Essential textbooks, Dr Robert Cubbidge describes the visual pathway and its relationship with the visual field. CET module C2354 This article has been adapted and abridged from Visual Fields by Dr THE DIMENSION of the blind spot Robert Cubbidge, is approximately 7.5º high and 5.5º wide part of the new and represents the temporal visual field Eye Essentials projection of the optic nerve, found series. For further approximately 1.5º below and 15º horizon- information, tally from fixation. When interpreting including ordering, please click on visual field defects, knowledge of the the Bookstore link arrangement of nerve fibres in the visual at www.optician pathway is essential. online.net Depending on the site of damage in the visual pathway, characteristic visual field defects are produced (Figure 1). course to the optic nerve as they are not Anatomically, the visual pathway hindered by the papillomacular bundle begins at the photoreceptors which lie in (Figure 2). The nerve fibres from the nasal the outer retina. Here, photons of light are retina do not cross those of the temporal absorbed by the photopigments, which are retina and thereby form a theoretical sensitive to specific regions of the visible vertical line of demarcation which passes electromagnetic spectrum. Light energy through the centre of the fovea. -
Tissue-Engineered Models for Glaucoma Research
micromachines Review Tissue-Engineered Models for Glaucoma Research Renhao Lu 1 , Paul A. Soden 2 and Esak Lee 1,* 1 Nancy E. and Peter C. Meinig School of Biomedical Engineering, Cornell University, Ithaca, NY 14853, USA; [email protected] 2 College of Human Ecology, Cornell University, Ithaca, NY 14853, USA; [email protected] * Correspondence: [email protected]; Tel.: +1-607-255-8491 Received: 5 June 2020; Accepted: 22 June 2020; Published: 24 June 2020 Abstract: Glaucoma is a group of optic neuropathies characterized by the progressive degeneration of retinal ganglion cells (RGCs). Patients with glaucoma generally experience elevations in intraocular pressure (IOP), followed by RGC death, peripheral vision loss and eventually blindness. However, despite the substantial economic and health-related impact of glaucoma-related morbidity worldwide, the surgical and pharmacological management of glaucoma is still limited to maintaining IOP within a normal range. This is in large part because the underlying molecular and biophysical mechanisms by which glaucomatous changes occur are still unclear. In the present review article, we describe current tissue-engineered models of the intraocular space that aim to advance the state of glaucoma research. Specifically, we critically evaluate and compare both 2D and 3D-culture models of the trabecular meshwork and nerve fiber layer, both of which are key players in glaucoma pathophysiology. Finally, we point out the need for novel organ-on-a-chip models of glaucoma that functionally integrate currently available 3D models of the retina and the trabecular outflow pathway. Keywords: glaucoma; tissue engineering; trabecular meshwork; Schlemm’s canal; retinal ganglion cell; intraocular pressure; optic nerve head; electrospinning; soft lithography; 3D scaffold; 3D bioprinting 1.