Author : Deborah Awisi-Gyau
Publisher :
ISBN 13 :
Total Pages : 205 pages
Book Rating : 4.6/5 (624 download)
Book Synopsis Characterization of Tear Breakup and Its Sensory Responses by : Deborah Awisi-Gyau
Download or read book Characterization of Tear Breakup and Its Sensory Responses written by Deborah Awisi-Gyau and published by . This book was released on 2020 with total page 205 pages. Available in PDF, EPUB and Kindle. Book excerpt: Dry eye disease (DED) affects millions of people in the United States and worldwide. Tear film instability (TFI) and hyperosmolarity have been implicated in the etiology of DED, which is characterized by a loss of homeostasis of the tear film. Theoretically, tear film evaporation is the main factor leading to TFI, resulting in an increased tear film osmolarity and possible "dry spots" when tear film disruption or breakup (TBU) occurs. These adverse conditions in the tear film may damage the ocular surface and stimulate underlying corneal sensory nerves, leading to the symptoms of ocular irritation characteristic of DED. However, the link between the symptoms of DED and TFI remains poorly understood because many highly symptomatic DED patients show little or no ocular surface damage to account for their symptoms. In this thesis, I address this gap in our knowledge by investigating the connection between TFI and the sensory response of the ocular surface epithelium. In the series of experiments described in this thesis, we use a human based method developed in our lab to stimulate TBU and study the formation and progression of TBU. Further, we develop methods to obtain known concentrations of fluorescein and lissamine green, characterize TBU patterns and its impact on corneal sensory thresholds. We hypothesize that TFI can alter the epithelial surface environment by chemical, thermal, and mechanical changes in the tear film, which can stimulate underlying sensory nerves, without clinically observable surface damage. Further, we theorize that repeated TFI and, thus, recurring stimulation of ocular surface sensory neurons leads to altered sensory thresholds and persistent discomfort.