رسالة جامعية

Automatic detection of fluorescein tear breakup sequence

التفاصيل البيبلوغرافية
العنوان: Automatic detection of fluorescein tear breakup sequence
المؤلفون: Yedidya, Tamir
سنة النشر: 2018
المجموعة: Australian National University: ANU Digital Collections
مصطلحات موضوعية: RE216.D78 Y43 2010, Dry eye syndromes Diagnosis, Diagnostic Techniques, Ophthalmological, Algorithms
الوصف: Dry Eye Syndrome is a common disease in the western world, with effects from uncomfortable itchiness to permanent damage to the ocular surface. Almost 5 million Americans over 50 years old suffer from dry eye. A conservative estimate shows that approximately 17 million Americans have contact lens related dry eye -one of the main factors to contact lens discontinuation. In addition, the incidence of the disease is on the rise. Nevertheless, there is still no gold standard test that can reliably detect dry eye. One of the most commonly used tests by clinicians to detect dry eye is the Fluorescein Break Up Time (FBUT). However, results vary a lot between clinicians. Other tests such as observing the tear meniscus height are also performed regularly by the clinicians but not necessarily in conjunction with the FBUT test. Therefore there is a real need for a reliable, robust and operator-dependent method to evaluate dry eye. To our knowledge, no previous research has been conducted on automatic evaluation of dry eye in fluorescein images. In this thesis, we present new algorithms to automatically detect various dryness signs and make a number of original contributions. The first problem we address is how to detect the dry areas in fluorescein videos of the anterior of the eye, which are captured using a portable camera. We present a new multi-step algorithm which first locates the iris in each image in the video, then aligns the images according to the location of the iris and finally analyzes the aligned video to find the regions of dryness. We produce a novel segmentation result called dryness image, which depicts the various degrees of tear film thinning over the corneal surface. Then, we demonstrate through experiments that there is a large variation in the estimated Break Up Time (BUT) between clinicians and no ground-truth can be defined. To overcome that, we define a new value based on the clinical definitions of the BUT. These definitions are converted to image processing properties and an estimate of the BUT ...
نوع الوثيقة: doctoral or postdoctoral thesis
وصف الملف: xii, 216 p.
اللغة: English
العلاقة: b2520226; http://hdl.handle.net/1885/150184Test; https://openresearch-repository.anu.edu.au/bitstream/1885/150184/5/b25202261_Yedidya_T.pdf.jpgTest
DOI: 10.25911/5d6119bf78284
الإتاحة: https://doi.org/10.25911/5d6119bf78284Test
http://hdl.handle.net/1885/150184Test
https://openresearch-repository.anu.edu.au/bitstream/1885/150184/5/b25202261_Yedidya_T.pdf.jpgTest
حقوق: Author retains copyright
رقم الانضمام: edsbas.65ED886A
قاعدة البيانات: BASE