City Research Online City, University of London Institutional Repository Citation: Vemala, R. (2018). Loss of chromatic sensitivity in patients with age-related maculopathy - correlation with structural changes in the retina. (Unpublished Doctoral thesis, City, University of London) This is the accepted version of the paper. This version of the publication may differ from the final published version. Permanent repository link: https://openaccess.city.ac.uk/id/eprint/26212/ Link to published version: Copyright: City Research Online aims to make research outputs of City, University of London available to a wider audience. Copyright and Moral Rights remain with the author(s) and/or copyright holders. URLs from City Research Online may be freely distributed and linked to. Reuse: Copies of full items can be used for personal research or study, educational, or not-for-profit purposes without prior permission or charge. 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City Research Online: http://openaccess.city.ac.uk/ [email protected] Loss of chromatic sensitivity in patients with age-related maculopathy - correlation with structural changes in the retina Mrs Roopa Vemala Doctor of Philosophy Applied Vision Research Centre School of Health Sciences City, University of London January 2018 CONTENTS Table of Contents TABLE OF FIGURES: ................................................................................................................................. 7 List of Tables ......................................................................................................................................... 12 Acknowlegements: ................................................................................................................................ 14 Declaration: ........................................................................................................................................... 15 Symbols and Abbreviations: ................................................................................................................. 16 Abstract ................................................................................................................................................. 18 Introduction: ......................................................................................................................................... 21 Aims of the study: ................................................................................................................................. 24 1. Anatomy and physiology of the eye with special relevance to AMD: .............................................. 25 The Human Eye: ................................................................................................................................ 25 1.1 Bruch’s Membrane: .................................................................................................................... 26 1.1.1a Lipid Accumulation in Bruch's membrane: ........................................................................ 27 1.1.2 Relevance to Age- related macular degeneration: .............................................................. 28 1.1.2a Drusen: ............................................................................................................................... 29 1.1.2b Basal Linear deposit (BlinD) and Basal Laminar deposit (BlamD): ..................................... 30 1.1.2c Reticular Drusen: ................................................................................................................ 30 1.1.2d Thick basal laminar deposits in adult-onset autosomal dominant inherited disorders: ... 33 1.1.2e Response to retention hypothesis of AMD: ....................................................................... 34 1.1.2f Neovascular AMD: .............................................................................................................. 34 1.2 Choroid: ....................................................................................................................................... 35 1.2.1 Choriocapillaris:.................................................................................................................... 36 1.2.2 Choroid vascular layers and the suprachoroid: ................................................................... 37 1.2.3 Choroid Blood flow: Nourishment of the retina: ................................................................. 37 1.2.4 Age-related maculopathy/AMD relevance: ......................................................................... 38 1.3 Retina: ......................................................................................................................................... 39 1.3 .1 The Macula: ......................................................................................................................... 42 1.3 .2 Peripheral retina: ................................................................................................................ 43 1.3.3 Retinal Pigment Epithelium: ................................................................................................ 44 2 CONTENTS 1.3.3a Functions of the RPE: ......................................................................................................... 44 1.3.3b Age-related maculopathy/ AMD relevance: ...................................................................... 46 1.3.4: Photoreceptors: .................................................................................................................. 47 1.3.4 a Different types of cone photoreceptors: .......................................................................... 50 1.3.4 b The density of Rods and Cones in the human retina: ....................................................... 51 1.3.4 c Age-related maculopathy and AMD relevance: ................................................................ 53 1.3.5 Ganglion cells: ...................................................................................................................... 53 1.3.5 a Aging and Age-related maculopathy/AMD relevance: ..................................................... 54 2. Age-related macular degeneration: ................................................................................................. 56 2.1 Introduction to AMD: .................................................................................................................. 56 2.2 Epidemiology, risk factors, and natural history: ..................................................................... 57 2.2a Risk factors: ........................................................................................................................... 57 2.2 b Genetic Factors: ................................................................................................................... 58 2.3 Normal Aging: ............................................................................................................................. 59 2. 4 Early and intermediate AMD: .................................................................................................... 60 2.4 a Drusen: ................................................................................................................................. 61 2.4 b Changes in RPE: .................................................................................................................... 62 2.4 c Histology: .............................................................................................................................. 63 2.5: Reticular Pseudo drusen (RPD): ............................................................................................. 63 2.5a Genetic and environmental factors: ..................................................................................... 66 2.5 b Path physiology: ................................................................................................................... 66 2.5 c Histology: .............................................................................................................................. 67 2.6. Late or advanced Age-Related Macular Degeneration: ............................................................. 69 2.6.1. Dry AMD: ............................................................................................................................. 69 2.6.2 Wet AMD:............................................................................................................................. 72 2.6.2aa Wet AMD Characteristics: ................................................................................................ 73 1. RPE detachment/Pigment epithelial detachment (PED): ......................................................... 73 2. Choroidal neovascular membrane: ........................................................................................... 74 3. Disciform Scar ........................................................................................................................... 75 2.7 Imaging Modalities in AMD ......................................................................................................... 77 2.7.1. Grading of ARM /AMD on Fundus photographs: .................................................................... 77 2.7.2 Optical coherence tomography (OCT): ...............................................................................