Optic nerve microstructure: a significant indicator of disease severity

Glaucoma is the second most common cause of irreversible blindness and in 50% of cases is undetected. Primary open-angle glaucoma results in retinal cell and axon death leading to bilateral blindness in 4-6.3% of patients.

This research aims to characterise microstructural features within optic nerve heads that can be used to identify those optic nerves that are at risk of either development of the disease or of rapid progression. Early detection of disease onset of glaucoma is critical to prevent irreversible axon and vision loss.

This study will be achieved using a novel imaging device called optical coherence tomography. Our device uses a longer wavelength of light than many commercial devices, which enables us to visualise the structures within the retina and optic nerve. There is now substantial evidence that changes in the lamina cribrosa, a supportive structure to axons within the optic nerve as it leaves the eye on its journey to the brain, initiates retinal ganglion cell (RGC) death in glaucoma. Thus the principal outcome measure of this study is anticipated to be the characterisation of the lamina cribrosa configuration at different stages of disease, in relation to cell and axon loss in the eye blinding disease, glaucoma. In addition, as there is variation in eyes in the normal population, a number of other ocular features will be taken into account when evaluating statistical significance to remove any biase with respect to influencers such as ocular size and age.

The outcomes of this study will be of great importance for the discrimination of patients who are at risk of developing glaucoma (e.g. ocular hypertensive patients) or glaucomatous disease progression. In turn, this will enable earlier intervention, prior to irreversible vision loss.