Discovering an Invisible Layer in Retina and Its Ties to AMD

To develop a retinal imaging device called volumetric directional Optical Coherence Tomography (VD-OCT), which will allow us to visualize a normally invisible retinal layer and study its role in age-related macular degeneration (AMD).

Aim 1: Develop an advanced retinal imaging device for measuring the true thickness of the outer nuclear layer (ONL) in the entire macular region, by: 1. Improving imaging speed, 2. Developing novel scanning patterns, 3. Training artificial intelligence to fully automate the imaging acquisition. Aim 2: Pilot imaging studies using the VD-OCT prototypes. First step: a pilot validation study on normal subjects. The second step is a short-term prospective observational study to measure the thickness of ONL in intermediate-stage dry-AMD patients and healthy age-matched control subjects.

Our proposed volumetric directional optical coherence tomography (OCT) can visualize a retinal layer (Henle’s fiber layer) that is invisible in the current OCT retinal imaging devices. This discovery leads to the precise measurement of the true outer nuclear layer thickness, which is an important biomarker for photoreceptor health. We will also leverage the recent development in laser technology to significantly increase imaging speed and artificial intelligence to automate the imaging procedure which could significantly improve the clinical utility.

Our VD-OCT will provide an accurate measurement of ONL thickness. An improved understanding of photoreceptor cell loss around the drusen and in the wider macula will allow new insight into AMD progression and provide precise imaging biomarkers for AMD clinical trials. In this study, OCT biomarkers reflecting photoreceptor degeneration will allow earlier identification and quantification of progression to advanced AMD. Finally, in the context of current and future gene- and cell-based therapies, precise measurements of the ONL may prove to be an important quantitative imaging biomarker of regeneration.