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Introduction
Published in Arwa Ahmed Gasm Elseid, Alnazier Osman Mohammed Hamza, Computer-Aided Glaucoma Diagnosis System, 2020
Arwa Ahmed Gasm Elseid, Alnazier Osman Mohammed Hamza
In the cases of glaucoma in which the visual field test result and IOP assessment are not reliable, e.g., for advanced AMD disease (Age-related Macular Degeneration), the visual field measurement is usually carried out using a static perimeter, which is difficult for different diseases and it needs patient cooperation to follow the instructions. In this case, the IOP is not sensitive because in some kinds of glaucoma the pressure is normal, which is called normal tension glaucoma, and the best ways to detect glaucoma via ONH and imaging modality (OCT, HRT) are expensive. It is then necessary to search for other methods which will enable a determination of the glaucoma disease. One such method is the analysis of digital fundus images of the eye fundus taken via a fundus camera device.
Neuro-Ophthalmology
Published in Anthony N. Nicholson, The Neurosciences and the Practice of Aviation Medicine, 2017
It is not necessarily the case that these are the appropriate weightings for occupational decisions or for driving and aviation safety. Nonetheless, the Esterman binocular visual field test (now carried out as a built-in paradigm using the Humphrey automated perimeter) has become the gold standard for the United Kingdom Department of Transport in assessing fitness to drive. It has the advantages that it is quick and universally available, and, although it might be possible to design a test with theoretically more appropriate weightings for visual requirements of driving, there is very little scientific evidence on which to base the judgements. Binocular visual field testing is problematic because, particularly with the viewing distance of 50 centimetres, it is necessary for the subject to make a vergence effort to fix on the target, which can lead to inconsistencies in performance.
Visual changes with aging
Published in Pablo Artal, Handbook of Visual Optics, 2017
Visual fields are widely believed to be important for safe driving and are included in driver licensing standards in many countries, although the exact field requirements vary between states and countries. Visual field tests commonly used for assessing fitness to drive include the binocular Esterman visual field test (EVFT) and Medmont driving test, both of which extend beyond the central 30° and involve suprathreshold targets. Merging two monocular threshold fields, known as the integrated visual field (IVF), may be as useful as the EVFT in assessing fitness to drive in patients with a range of field loss (Crabb et al. 2004, Chisholm et al. 2008), particularly given that monocular fields are routinely assessed in patients with ocular disease; however, the link between IVF and crash risk has yet to be determined.
Glaucoma Detection Using Optical Coherence Tomography Images: A Systematic Review of Clinical and Automated Studies
Published in IETE Journal of Research, 2022
Hina Raja, Muhammad Usman Akram, Taimur Hassan, Aneeqa Ramzan, Amtual Aziz, Hira Raja
The study [26] presented the investigation to find the functional and structural relationship between peripapillary NFL thickness, macular thickness, and automated visual field through OCT imaging. About 150 eyes of 101 subjects were under investigation with the OCT scan of peripapillary NFL thickness, visual field test, and orthogonal OCT of macula region. The area under ROC curves used to measure the relationship between the visual field findings, peripapillary NFL thickness, macular retinal thickness, and visual defect are restricted to only one hemifield. The correlation of peripapillary NFL thickness with macular retinal thickness for quadrants ranged from 0.27 to 0.54, hemiretina 0.44–0.55, and for mean, it was 0.52. Macular thickness had higher AROCs in areas with visual defects and was capable of detecting the damage caused by glaucoma. However, the peripapillary nerve fiber layer had high areas under the ROC than macular retinal thickness for the detection of visual field abnormalities. Ojima et al. [27] signify that macular volume and retinal nerve fiber layer thickness decreased in glaucoma; furthermore, RNFL thickness had a higher diagnostic accuracy than the macular volume.
Performance-based visual field testing for drivers with glaucoma: A pilot study
Published in Traffic Injury Prevention, 2018
Hannes Devos, Maud Ranchet, Kathryn Bollinger, Amber Conn, Abiodun E. Akinwuntan
In conclusion, we have developed a performance-based visual field test to detect visual field impairments while driving in glaucoma. The test has acceptable test–retest reliability and construct validity. Yet, caution with the interpretation is warranted because the study’s sample size was small and only included drivers with mild glaucoma. The current results should therefore be considered as exploratory and be confirmed in studies with larger sample sizes. Future research should also include older individuals with diverse visual field defects and more severe driving impairments to establish concurrent and predictive validity against on-road testing and MVCs.
Out with the old, in with the new: how changes in cricket helmet regulations affect the vision of batters
Published in Journal of Sports Sciences, 2019
Luke Wilkins, David Mann, Stephen Dain, Thomas Hayward, Peter Allen
Data were analysed using SPSS Statistics version 23. Paired samples t-tests were used to investigate the difference in the number of points seen on the visual field test between the old and new helmet. Further paired-samples t-tests were conducted for each individual visual field point in order to identify the location of any potential differences in visual field visibility between the two helmets. An alpha level of p = .05 was used to indicate significance.