PhD Study : ​Towards seeing clearly: does the shape of the eye’s optics affect our focus? ​

Summary

Visual problems are common in Down syndrome (DS), including reduced vision, refractive errors, cataract and keratoconus (Haugen et al. 2001, Little et al. 2007, 2009, Ljubic et al. 2011). Life expectancy in DS has increased substantially in recent years; thus the focus of medical care in Down syndrome has shifted to quality of life and management of treatable illnesses (Lott et al. 2010, Bittles et al. 2007).  Consequently, maximising vision in this population should be a priority to positively impact on visual, intellectual and social development.

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 change focus on objects at different distances (Dubbelman & Van der Heijde 2001).  This occurs through adjustment of the crystalline lens shape by the action of the intra-ocular ciliary muscle. The structure of the DS eye is known to differ, with thinner crystalline lenses and steeper corneae (Haugen et al. 2001, Little et al. 2009). 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 is a frequent finding in DS.

Our group have also reported that the DS eye has an increased magnitude of whole-eye higher order aberrations (McCullough et al. 2013). With advances in faster acquisition and higher resolution, it is now feasible to capture images of the lens of the eye in DS, as shown by our recent study which has successfully employed ocular coherence tomography (OCT) and bespoke slit-lamp photographic imaging of the eye in DS to examine cataract (Little et al. 2020).

The next important step in understanding the impact of the difference eye shape may make to vision and accommodation is investigation of the shape of the lens through computational modelling of the eye in DS.  The eye is a system by which computational modelling is strongly promising to help us understand the genetic and age-related changes that occur. There are a few studies which have recently used finite element modelling to try to understand the forces and flex of the lens during accommodation and these both move research forward in building a whole-eye model of accommodation, but also highlight the remaining uncertainties with assumptions about the refractive index and makeup 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, changes in lens shape and the impact of blur cues and spherical aberration will be investigated and compared to a typical ‘control’ model. This study will address the question of whether the structure of the eye in DS is not conducive to exhibiting accurate accommodation. This project extends the long-standing research

Please note: Applications for more than one PhD studentships are welcome, however if you apply for more than one PhD project within Biomedical Sciences, your first application on the system will be deemed your first-choice preference and further applications will be ordered based on the sequential time of submission. If you are successfully shortlisted, you will be interviewed only on your first-choice application and ranked accordingly. Those ranked highest will be offered a PhD studentship. In the situation where you are ranked highly and your first-choice project is already allocated to someone who was ranked higher than you, you may be offered your 2nd or 3rd choice project depending on the availability of this project.

AccessNI clearance required

Please note, the successful candidate will be required to obtain AccessNI clearance prior to registration due to the nature of the project.

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
• Clearly defined research proposal detailing background, research questions, aims and methodology

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.

• Completion of Masters at a level equivalent to commendation or distinction at Ulster
• Experience using research methods or other approaches relevant to the subject domain
• Sound understanding of subject area as evidenced by a comprehensive research proposal
• Work experience relevant to the proposed project
• Publications record appropriate to career stage
• Experience of presentation of research findings
• A comprehensive and articulate personal statement
• Relevant professional qualification and/or a Degree in a Health or Health related area

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