Abstract
Purpose :
To apply a non-invasive optical coherence tomography (OCT) based technique to quantitatively assess the pulsatile displacement of the optic nerve head (ONH) tissue in glaucoma patients before and after treatment (intraocular pressure (IOP) lowering)
Methods :
Participants with a diagnosis of primary open-angle glaucoma (POAG), treated with medical or surgical treatment, with a minimum IOP drop of 4 mmHg, were imaged with an OCT using a video modality. After rigid registration, a previously published and validated algorithm based on non-rigid registration was applied to measure maps of local pulsatile displacement in the ONH based on high-frequency OCT imaging. Displacement was measured in a cohort of 18 participants before and after IOP lowering treatment (both medical and surgical intervention). Intraocular pressure was measured by dynamic contour tonometry (Pascal). Treatment selection was not part of the study design as it was part of the standard medical care.
Results :
A total of 18 participants with POAG diagnosis (6 moderate and 12 advanced), were imaged before and after intervention. Mean age was 67±4years. Mean IOP drop was 11.1mmHg. Before intervention there was a median pulsatile displacement of 9.12±2μm compared to a displacement of 7.7±1μm after IOP decrease (p<0.01). Therefore, there was a mean 15% decrease in pulsatile displacement after intervention compared to baseline. Multivariate analysis showed no significant correlation with age, sex, disease stage or absolute IOP change.
Conclusions :
Our non-invasive method demonstrates decrease in the ONH tissue pulsatile deformation after IOP lowering. This could lead to possible biomechanical understanding of the therapeutic response in glaucoma patients. Further research is required to replicate the results but the clinical applications of our novel method show great translational value.
This abstract was presented at the 2023 ARVO Annual Meeting, held in New Orleans, LA, April 23-27, 2023.