Ocular Discomfort Upon Tear Drying

.............................................................................................................................. iii Acknowledgements............................................................................................................. iv Dedication ............................................................................................................................ v TABLE OF CONTENTS........................................................................................................ vi LIST OF FIGURES ............................................................................................................... xii LIST OF TABLES................................................................................................................ xiv LITERATURE REVIEW: ....................................................................................................... 1 1. Dry Eye and the Sensation of Ocular Dryness: .............................................................. 1 Cutaneous Dryness: What do we mean by the term Dry Skin?...................................... 2 Neural Mechanisms of Dry Skin Perception: .............................................................. 3 Peripheral Afferents of Mechanoreception and their Psychophysical Channels: .... 4 Relation of Intensity of Stimulus to Magnitude of Sensation:................................. 7 A Note about the evolution of the mucous surface to reduce the drag force:................. 8 2. Neural coding mechanisms of roughness in skin:........................................................... 9 Perception of Moving Stimuli in the Skin: ................................................................ 10 Molecular mechanisms of mechanosensation and its relevance to the ocular surface: .................................................................................................................................... 11 3. Epidemiology of Dry Eye, Dry Skin and Dry Mouth:.................................................. 15 Epidemiology of Dry Skin:........................................................................................... 15 Oral Dryness – What do we mean by the term Dry Mouth? ........................................ 16 Ocular Drying: What do we mean by the term Dry eye? ............................................. 18 The Epidemiology of Dry Mouth and Dry Eye (ICD-9 #375.15): ............................ 18