Optik und Mechatronik
Refine
Document Type
- Master's Thesis (19) (remove)
Has Fulltext
- yes (19) (remove)
Is part of the Bibliography
- no (19)
Keywords
- Myopia (2)
- Abschlussarbeit (1)
- Auditive und taktile Stimulation (1)
- Augenoptik-Branche (1)
- Augenoptikmarkt (1)
- Belastungsstörungen (1)
- Choroidal thickness (1)
- Comparison metrics (1)
- Defocus (1)
- Diffusion (1)
Institute
Purpose: Usually, a theory of attention upon gazed-at locations is applied. More parameters than gaze location can be derived to improve the theory of attention allocation. The aim of this study was to identify parameters related to eye tracking, that are suitable indicators of attention.
Methods: Binocular eye tracking data was collected with the Eye Tribe tracking system (The Eye Tribe Aps, Copenhagen, Denmark) for the task of visual exploration of the painting “Unexpected Visitors” by Ilya Repin. 20 subjects (valid data: 19/20) had to look at this painting for about two and a half minutes in order to generate fatigue and inattention. In a second step, suitable parameters of attention were transferred to a data set (8 subjects, valid data: 6/8) on a perimetric task executed with the OCTOPUS 900 perimeter (Haag-Streit, Köniz, Switzerland). Monocular parameters could be applied on the perimetric task, the error rate (false positive and false negative catch trials, 5 % each) were taken as additional parameter.
Results: For the image viewing task, the only parameter showing significance was the average level (a10) of fatigue waves (p = 0.00024, ANOVA, ∆ = -0.8316 px). Blink duration (∆ =-270.4 ms), pupil variability (∆ = -0.17868), saccade length (∆ =-0.3135 px) and fixation duration (∆ = 186.5 ms) did not change significantly, but showed relevant trends by differences ∆ of their median between the first and last tenth of the recording time. Blink rate and the Index of Cognitive Activity (ICA) did neither show significant changes nor relevant trends. Vergence accuracy failed to indicate fatigue due to variability between subjects and comparatively small effect size. For the perimetric data, in 3 of 6 subjects fatigue waves over a limited time window could be observed. Only for one subject, a relevant increase in false negative responses to catch trials (50 percentage points) could be observed.
Conclusion: Pupil diameter variability, saccade length, fixation duration and fatigue waves were the parameters indicating fatigue. Only the latter parameter has the potential to be applied to perimetric data.
This research project is of particular importance since there is a lack of adequate data on pediatric eye and vision disorders in Russia, particularly in the Volga region. In the present study, we estimate the prevalence of vision disorders among school-aged children who participated in a vision screening program in Samara, Russia. The relationship between learning-related visual dysfunctions is explored in depth, such to illustrate the connection between vision and learning. Hence, a key feature in this study is the inclusion of binocular vision disorders among the conditions tested.
In Branchen wie Luftfahrt, Hotellerie oder Autovermietungen gehört «Revenue-Marketing» (kurz: RM) in Form von dynamischer Preisgestaltung schon lange zum angewendeten Standard. Ziel dieser Studie ist herauszufinden, wie die Haltung der schweizerischen Augenoptikerbranche gegenüber «Revenue-Marketing» ist. Es wird analysiert, wie viele Augenoptikfachgeschäfte in der Schweiz dynamische Preise anwenden und wie viele diese nicht anwenden. Es wird analysiert, wie die dynamischen Preise gesteuert werden und welche Produkte betroffen sind. Werden noch keine dynamischen Preise verwendet, wird nachgefragt, ob eine mögliche Einführung geplant ist. Sofern keine Einführung geplant ist, werden die Ablehnungsgründe analysiert. Zudem wird geforscht, ob die Firmengrösse einen Einflussfaktor auf die Verwendung von «Revenue-Marketing» hat.
Purpose: Recent studies found a reduction of myopia progression with multifocal contact lenses, however, with yet unclear mechanism. This raises the hypothesis that the addition zones of the multifocal contact lenses induce myopic defocus on the retina, which consequentially leads to choroidal thickening and therefore inhibited eye growth. We tested the effect of the optical design of multifocal contact lenses on choroidal thickness.
Methods: 18 myopic students wore four different contact lenses ((1) single-vision lens corrected for distance, (2) single-vision lens with +2.50 D full-field defocus, (3) “Multifocal center-distance” design, addition +2.50 D, (4) “Multifocal center-near” design, addition +2.50 D) for each 30 minutes on their right eye. Automated analysis of the macular choroidal thickness, vitreous chamber depth and eccentric photorefraction were performed before and after each contact lens.
Results: Choroidal thickness and vitreous chamber depth showed no significant differences to baseline with none of the contact lenses. Choroidal thickness increased the most with the “Multifocal center-distance” and the full-field defocus lens, followed by the “Multifocal center-near” and the single-vision contact lens (+2.1 ± 11.1 μm, +2.0 ± 11.1 μm, +1.6 ± 11.3 μm, +0.9 ± 11.2 μm, respectively). The “Multifocal center-distance” design showed an overall more myopic refractive profile than the other lenses. Changes of vitreous chamber depth occurred in anti-phase to these of choroidal thickness.
Conclusion: Multifocal contact lenses have no significant influence on choroidal thickness and after short-term wear. Therefore, it is assumed that it is not the main contributor to the protective effect of multifocal contact lenses in myopia control.
Purpose: The aim is to be able to advise patients on the choice of sports and exercises regarding the effects on the intraocular pressure.
Methods: The search engines Google Scholar and PubMed were used to search for suitable studies. The studies were summarized, and the most important data were collected in one table for each study. The effect on the IOP was extracted or, if not given in the article, calculated by the difference of means of the IOP after or during exercise, and the baseline IOP before, whenever these values were available.
Findings: A total of 47 studies out of the years 1990 to 2020 that investigated the influence on the IOP of the most popular sports actively practiced in Germany were reviewed and summarized: twelve for running, sixteen for fitness/ weight training, one for swimming/diving, twelve for cycling, four for hiking, and two for yoga.
Conclusions: Throughout all studies and sports it was seen that physical fitness stabilized the IOP. Higher
intensity of exercise led to higher fluctuations of the IOP. Moderate endurance training keeps the IOP fluctuations low and may lead to a lower baseline IOP if practiced on a regular base. Fitness and weight training lead to fluctuations of the IOP in a pronounced manner when performed at moderate and high intensity. Therefore, only a moderate training can be recommended if there is need to keep the IOP stable. Isometric exercise is not recommended as it provokes a rise of the IOP even when performed with light loads. The Valsalva Maneuver should always be avoided as it leads to additional fluctuations of the IOP. Also, the IOP behaved more stable during resistance training when higher fitness was present.
The direct ophthalmoscope is a retinal screening tool that has been in existence and development for more than 150 years, yet, the rapid influence of technological evolution in screening tools, has left the direct ophthalmoscope untouched. The main purpose of this master thesis is to determine if the direct ophthalmoscope has reached its maximum potential of development and, additionally, to determine if a further development, including a more electronic input, would be feasible.
Demographische Veränderungen durch eine zunehmende Alterung der Gesellschaft und eine Zunahme an Erkrankungen wie der AMD, des Glaukoms und der diabetischen Retinopathie stellen ophthalmologische Versorgungs- und Vorsorgemaßnahmen in Deutschland vor immer größere Herausforderungen. Einen wesentlichen Beitrag zur Sicherung der Vorsorgemaßnahmen können in der Zukunft Optometristen leisten. Mit Hilfe modernster Technologien, wie dem Ultra-Widefield-cSLO (Optos Daytona, können auch bei kleinen Pupillendurchmessern 200° Aufnahmen vom Augenhintergrund erstellt werden.
Das trockene Auge ist eine komplexe Erkrankung des vorderen Augenabschnitts. Es gibt eine Vielzahl von Ursachen, sowie eine Vielzahl an Therapiemöglichkeiten. Diese Arbeit befasst sich mit Benetzungsmitteln als Therapieform. Es existieren verschiedene Benetzungsmittel, die sowohl von Augenärzten, als auch von Optometristen und Optikern verabreicht werden. Es wird eine Übersicht über alle Benetzungsmittel erstellt, die in der Schweiz von Optometristen verabreicht werden können und ein Schema zur Anwendung je nach Diagnose entwickelt.