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Development and validation of a digital quantitative orthoptics workstation

Mohamad Shahimin, Mizhanim 2012. Development and validation of a digital quantitative orthoptics workstation. PhD Thesis, Cardiff University.
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The objective of the research is to provide the clinician with a simple system for making quantitative measurements that is comparable to the services of a skilled orthoptist. As many optometrists do not possess the necessary equipment for making such assessments, this technology would significantly enhance their referral capabilities. Reviews of the tests involved and instruments available are detailed in Chapter II and III. Chapter IV presents the various validation experiments carried out on the Tobii X120 eye tracker, concentrating on technical specifications such as, linearity range, optimum measurement distance and setup (with and without chin rest). We also investigated the effect of wearing different types of lens materials and pupil size measurements on the eye tracker system. We established the inter-examiner agreement of cover test measurements on groups of non-strabismic and strabismic subjects. This study, as detailed in Chapter V, involved collaboration with two clinical orthoptists. We found a good inter-examiner agreement for both the non-strabismic and strabismic cover tests. We further investigated the use of the eye tracker in providing more reliable findings for cover test measurements as compared to the conventional cover test (Chapter VI). Finally we extended the investigation to a number of different clinical subjects attending the Bristol Eye Hospital (Chapter VII) in order to evaluate our purpose-developed monocular calibration routine. Performing quantitative eye movement analysis will provide valuable additional information in any clinical investigation of patients with ophthalmological and/or neurological disorders, leading to greater precision in diagnosis. Traditional methods for the evaluation of oculomotor disorders rely on the diagnostic and therapeutic judgements by the examining clinicians and subjective responses from the patient. However, the use of currently available eye movement recording system will provide valuable alternatives for obtaining more objective and quantitative measurements.

Item Type: Thesis (PhD)
Date Type: Completion
Status: Unpublished
Schools: Optometry and Vision Sciences
Subjects: R Medicine > RE Ophthalmology
Uncontrolled Keywords: cover test ; phoria ; infrared eye tracker
Date of First Compliant Deposit: 30 March 2016
Last Modified: 19 Aug 2021 13:06

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