PhD Study : Barriers to clear vision: does the shape of the eye’s optics affect our focus?

Summary

The eye has two main optical components, the cornea and the crystalline lens, which under optimum conditions should deliver focussed light to the retina, the photosensitive neural tissue at the back of the eye. Accommodation (focussing) is an important optical regulation that enables the eye to focus on objects at different distances.  This process requires adjustment of the crystalline lens shape by the action of the intra-ocular ciliary muscle.

Visual problems are common in Down syndrome (DS), including reduced vision, refractive errors, cataract and keratoconus. The structure of the DS eye is known to differ, with thinner crystalline lenses and steeper corneae. The atypical structure of the optics of the DS eye may be an underpinning reason for poorer vision, and may also contribute to hypo-accommodation, which our group have established are frequent findings in DS.

Our group have also reported that the DS eye has an increased magnitude of whole-eye higher order aberrations.

With technological advances (faster acquisition, higher resolution), it is now feasible to capture images of the crystalline lens in DS.  Our recent study successfully employed ocular coherence tomography (OCT) and bespoke slit-lamp photographic imaging to grade and quantify cataract in this group of patients. The next important step in understanding the impact the characteristic DS eye shape makes to vision and accommodation is through computational modelling of the eye and crystalline lens in DS.

Ocular structure lends itself to computational modelling, and holds significant promise as a method by which to understand the impact of genetic and age-related changes on the optical quality of the eye. Two studies have recently used finite element modelling to describe the forces and flex of the lens during accommodation and these studies move research forward in building a whole-eye model of accommodation, but also highlight the remaining uncertainties with assumptions about the refractive index and make-up of the lens. This study will analyse lens images, utilise information on the parameters of the optical components of the eye, and establish a computational model of the DS eye.   Using the model, the impact of changes in lens shape, the availability of blur cues and spherical aberration will be investigated, and compared to a typical ‘control’ model. These investigations will primarily address the question of whether the structure of the eye in DS is not conducive to exhibiting accurate accommodation.

This study extends our group’s long-standing investigations relating to vision in DS and also broadens our focus beyond DS, to accommodative function in general. Decline in accommodative ability affects every human in the fourth and fifth decades of life, yet our understanding of the exact mechanism underlying accommodation remains limited.  It would be desirable for the PhD Researcher engaged in this study to have an optometric or clinical background, or to have experience in computational modelling/image analysis.

Essential criteria

Applicants should hold, or expect to obtain, a First or Upper Second Class Honours Degree in a subject relevant to the proposed area of study.

We may also consider applications from those who hold equivalent qualifications, for example, a Lower Second Class Honours Degree plus a Master’s Degree with Distinction.

In exceptional circumstances, the University may consider a portfolio of evidence from applicants who have appropriate professional experience which is equivalent to the learning outcomes of an Honours degree in lieu of academic qualifications.

• Sound understanding of subject area as evidenced by a comprehensive research proposal
• A comprehensive and articulate personal statement

Desirable Criteria

If the University receives a large number of applicants for the project, the following desirable criteria may be applied to shortlist applicants for interview.

• First Class Honours (1st) Degree
• Masters at 65%
• Completion of Masters at a level equivalent to commendation or distinction at Ulster
• Research project completion within taught Masters degree or MRES
• Experience using research methods or other approaches relevant to the subject domain
• Work experience relevant to the proposed project
• Publications - peer-reviewed
• Experience of presentation of research findings

Funding and eligibility

The University offers the following levels of support:

Vice Chancellors Research Studentship (VCRS)

The following scholarship options are available to applicants worldwide:

• Full Award: (full-time tuition fees + £19,000 (tbc))
• Part Award: (full-time tuition fees + £9,500)
• Fees Only Award: (full-time tuition fees)

These scholarships will cover full-time PhD tuition fees for three years (subject to satisfactory academic performance) and will provide a £900 per annum research training support grant (RTSG) to help support the PhD researcher.

Applicants who already hold a doctoral degree or who have been registered on a programme of research leading to the award of a doctoral degree on a full-time basis for more than one year (or part-time equivalent) are NOT eligible to apply for an award.

Please note: you will automatically be entered into the competition for the Full Award, unless you state otherwise in your application.

Department for the Economy (DFE)

The scholarship will cover tuition fees at the Home rate and a maintenance allowance of £19,000 (tbc) per annum for three years (subject to satisfactory academic performance).

This scholarship also comes with £900 per annum for three years as a research training support grant (RTSG) allocation to help support the PhD researcher.

• Candidates with pre-settled or settled status under the EU Settlement Scheme, who also satisfy a three year residency requirement in the UK prior to the start of the course for which a Studentship is held MAY receive a Studentship covering fees and maintenance.
• Republic of Ireland (ROI) nationals who satisfy three years’ residency in the UK prior to the start of the course MAY receive a Studentship covering fees and maintenance (ROI nationals don’t need to have pre-settled or settled status under the EU Settlement Scheme to qualify).
• Other non-ROI EU applicants are ‘International’ are not eligible for this source of funding.
• Applicants who already hold a doctoral degree or who have been registered on a programme of research leading to the award of a doctoral degree on a full-time basis for more than one year (or part-time equivalent) are NOT eligible to apply for an award.

Due consideration should be given to financing your studies. Further information on cost of living