28/10/2016

Author: Alejandra Consejo, Wroclaw University of Technology

Accommodation process (the ability of the eye to focus on close objects) has been widely studied. From a topographical point of view it is known that there is no change in the central corneal shape during the accommodation phase. However, little is known about how this process affects the entire anterior surface of the eye. Today it is possible to study the elevation of the whole anterior eye including cornea, corneo-scleral region and sclera. The work ‘Scleral changes with accommodation’, conducted in collaboration with The University of Manchester, was presented in the Visual and Physiological Optics (VPO) 2016 conference, held in Antwerp (Belgium). This study represents an analysis of how the shape of the anterior eye is affected by accommodation. We found that sclera undergoes changes during accommodation process and that this phenomenon is more pronounce in myopes than in emmetropes. This work was awarded with both the prize to the best student poster, sponsored by the Optical Society of America (OSA) and the prize to the best presentation design.

27/10/2016 

Author: Aikaterini Moulakaki, University of Valencia

19th October 2016. Sciences Library Hall, Burjassot Campus, University of Valencia

 

Conference organized by the University of Valencia related to the World Sight Day of the World Health Organization and the International Agency for the Prevention of Blindness. Open-door conference to all public that try to raise awareness about the importance of the Vision and their problems in the world. Marie Curie fellows of Ageye have explained their current projects, related to the Aging Eye, and their recent outcomes they have found. PI, Robert Montés-Micó introduced the Ageye ITN funded by the EU and other speakers have talked about their research and application to vision and cooperation in developing countries and visual health. Students and staff of the University of Valencia, and general public attended to the conference. 

 

Aikaterini Moulakaki in her presentation

 

Eleni Papadatou in her presentation

 

Georgios Zoulinakis in his presentation

 

Some of the speakers at the Conference, from left to right: Georgios Zoulinakis (AGEYE Marie Curie ESR), Daniel Monsálvez-Romín (FPU Predoc Researcher Ministerio de Educación), Edouard Lafosse (EDEN Marie Curie ESR), Aikaterini Moulakaki (AGEYE Marie Curie ESR), Eleni Papadatou AGEYE Marie Curie ESR), Antonio del Águila-Carrasco (ERC Predoc Researcher). 

26/10/2016

Author: Grzegorz Labuz, Rotterdam Ophthalmic Institute

The European Society of Cataract and Refractive Surgeons (ESCRS) is leading training and networking platform in Ophthalmology and Vision Science. The congress of the ESCRS takes place annually and attracts nearly 8000 delegates from almost 100 countries worldwide. This year, the meeting was organized in Copenhagen.

Sonia Gholami and Grzegorz Łabuz, two Early Stage Researchers from the Rotterdam Ophthalmic Institute, presented their scientific results at the ESCRS 2016 congress:

S. Gholami “Test of visual Strehl ratio metric to predict visual performance in healthy and cataract eyes

G. Łabuz “Straylight from explanted intraocular lenses

G. Łabuz “In-vitro evaluation of straylight from intraocular lenses with laboratory-induced glistenings

 The presentations were followed by a discussion with fellow researchers

26/10/2016

Author: Sonia Gholami, Rotterdam Ophthalmic Institute

Congenital cataract [1] is prevalent with 1 to 6 cases per 10,000 births which can occur in different morphological configurations. Young adults with this type of cataract usually have a very good visual acuity and since they are exposed to this issue since birth, their vision might be compromised. However the resultant visual malfunction are sometimes inevitable and becomes especially crucial for young adults with careers which require optimal visual performance. Congenital cataract in adults may cause issues such as lack of depth perception or poor retinal development due to stimulus deprivation amblyopia [2].

In a new study we want to investigate the angular-dependency of the forward light scattering in congenital cataract eyes (known as straylight) [3][4]. Straylight is the skirt of the point spread function (PSF) and covers the outer part (θ > 1°) of it. It was reported that straylight intensity decreases greatly with θ. The same study showed that straylight parameter changes from 2.5° to 25.4° with a parabolic behavior with a minimum value around 7° in normal eyes without cataract. Recently, in one pulverulent congenital cataract subject, we observed an atypical behavior of straylight compared to what is common in age-related cataract at large angle (28°) [4][5]. Straylight decreased, whereas the small-angle behavior was normal. However it appeared that the on-set cataract had no impact on the subject’s visual acuity. We expect high level of independency between straylight and visual acuity in congenital cataract eyes. Further, we are interested to know whether the unordinary features are results of a peculiar morphology. We will evaluate the relevant optical and visual measures including intraocular straylight as well as visual acuity, contrast sensitivity and wavefront aberration (visual Strehl ratio). We also survey the morphology of the cataract using retro-illumination images. 

 

Figure. A ring-shape pulverulent congenital cataract observed in one subject

[1] Reddy M., Francis P., Berry V., Bhattacharya S., and Moore A (2004). Molecular Genetic Basis of Inherited Cataract and Associated Phenotype. Survey of Ophthalmology, 49(3):300-15. [2] Antonio-Santos A., Vedula S., Hatt S., and Powell C (2014). Occlusion for stimulus deprivation amblyopia. Cochrane Database of Systematic Reviews 2014, Issue 2. Art. No.: CD005136. DOI: 10.1002/14651858.CD005136.pub3. [3] Van den Berg T., Franssen L., and Coppens JE (2009). Straylight in the human eye: testing objectivity and optical character of the psychophysical measurement. Ophthalmic Physiological Optics, 29(3):345-50.[4] Vos J., and van den Berg T. (1999). Report on disability glare. CIE Collection, 135:1-9. [5] Uspeert J., de Waard P., van den Berg T., and de Jong P. (1990). The intraocular straylight function in 129 healthy volunteers; dependence on angle, age and pigmentation. Vision Research, 30(5):699-707.

25/10/2016

Author: Juan F. Zapata-Díaz. The University of Manchester.

 

There is an increasing interest in the role of higher-order aberrations  (HOA) might play on depth-of-field (DoFi) of the eye. This knowledge could be of particular interest to enhance the devices (intraocular lenses, contact lenses…) used to mitigate the effects of presbyopia. Two of the partners of the Ageye consortium, The University of Manchester and The University of Murcia, have performed an original study in which an adaptive optics system was used to measure, correct and simulate the optical error (wavefront aberrations) of several participants. This allowed measuring depth-of-field of participants under 3 conditions: 1) with their own HOA; 2) after correction of their HOA; and, 3) under simulation of other participants’ HOA. This approach allowed participants to experience how other people see, as they would do with their own eyes. The results showed that the impact of optical factors on DoFi is approximately 20%, in average, of the DoFi total extent. Furthermore, the same HOA pattern had different effect on DoFi of different participants, showing an important role of factors outside the pure optical system of eye, as the neural processing of the retinal image.These results suggest that approaches that induce HOA to extend DoFi and mitigate the effects of presbyopia would benefit if they were done on a case-by-case basis. Furthermore, this study might offer a new method to measure the suitability of each patient to this kind of corrections to avoid post-treatment disappointment.

 

Top left: Adaptive Optics system used in the study (CiViUM lab, The University of Murcia). Top right: results of the impact of higher-order aberrations on depth-of-field extent. Bottom: ESR#5 presenting the study at ARVO annual meeting (Seattle, WA, USA).