Varsha Kadaba's bursary placement

Varsha Kadaba from Howell’s School, Llandaff in Cardiff spent 6 weeks in the School of Medicine at Cardiff University working in the Department of Opthalmology. Her project investigated the use of digital imaging in the early diagnosis of glaucoma.

The aims of the project
There were three aims of this project. Firstly, to determine the correlation and agreement between Heidelburg Retinal Tonnograph (HRTII) and Optical Coherence Tomograph (Status OCT) derived measurements of the retinal nerve fibre layer thickness, neuro-retinal rimarea, optic cuparea and optic disc area.

Secondly, to look at the repeatability of both techniques. Finally, this project studied the diagnostic precision of each testing technique for the early detection of glaucoma.

How the project was carried out
The data collected by the Heidelberg Retinal Tomograph (HRTII) and the Optical Coherence Tomograph (Stratus OCT) was analysed and compared to each other using statistical methods. To calculate the precision of the techniques, stereo photographs of optic nerve heads were used and graded by an ophthalmologist so that they could be compared to the diagnoses made by the two systems. The sensitivity and specificity were worked out for each technique.

The conclusions reached at the end of the project
The research found that the two systems did not correlate when measuring RNFL thickness but that this was due to other explainable factors. It also discovered that the OCT system is highly repeatable compared to the HRT system. The OCT system is more specific than HRT, although HRT is more sensitive than OCT.

The most valuable thing about the bursary experience
Being able to work alongside ‘real’ scientists and take part in a research project that had not been undertaken before. It was new and exciting.