Researcher Dr Zhichao Wu

Using OCT to better identify patients at risk

Researcher Associate Professor Zhichao Wu from the Centre for Eye Research Australia, was awarded $240,000 from the 2019 MDFA Research Grants Program. A/Prof Wu aimed to investigate new imaging techniques to improve the identification of who is at high risk of progressing to sight threatening late-stage (neovascular, wet or atrophic, dry) age-related macular degeneration (AMD).

Detecting and predicting who will progress from early or intermediate AMD to late AMD is challenging. Delays in detecting progression to the treatable wet AMD can lead to irreversible vision loss. A way of identifying high-risk individuals would improve the vision outcomes of many Australians.

A/Prof Wu’s project was called Predictive Imaging in the Early Stages of Age-Related Macular Degeneration (PRIME) study. He explains more about the inspiration and details of the study in this interview with MDFA volunteer, Clare Ashen.

A/Prof Wu says the imaging technique optical coherence tomography (OCT) shows promise as a powerful tool for identifying new indicators, or biomarkers of someone’s likelihood of developing late AMD. OCT imaging allows the back of the eye to be viewed 3-dimensionally, with each image holding a wealth of information on the light sensitive cells and supporting layers of the retina.

The study originally planned to perform OCT imaging with a newer-generation device to also detect changes in blood flow at the back of the eye, recruiting 200 people with intermediate AMD and following them over the course of the three-year project. Unfortunately, recruitment for the study commenced just as the Covid-19 pandemic struck, and lock downs and ongoing restrictions meant the research team had to re-focus the entire project.

A/Prof Wu and his team overcame this challenge by undertaking an extensive investigation into OCT and other imaging data from a previous study into the early stages of AMD. A/Prof Wu’s team scrutinised and analysed this imaging data to look for new predictive features of progression to late AMD. The researchers found that one of the strongest predictors of AMD progression were distinctive features on OCT images showing degeneration of the light-sensitive cells in the retina.

The findings from this study have been published in several high-profile scientific peer reviewed journals. A/Prof Wu and his colleagues have presented this work at numerous industry conferences. A/Prof Wu is using the knowledge gained from this study to contribute to clinical guidelines for optometrists on managing AMD. His research is ongoing to examine how using newer imaging techniques and artificial intelligence can be used to further improve our prediction of who is at risk of progression to late AMD.

Posted: 21 February 2024

This study has the potential to provide findings that can be used immediately in clinical practice.