Abstract
Purpose :
Retinal vein occlusion (RVO) is a leading cause of vision loss and blindness in older patients. We perform multimodal imaging with integrated photoacoustic microscopy (PAM) and spectral-domain optical coherence tomography (SD-OCT) to improve the efficiency for visualizing RVO and retinal neovascularization (RNV) in living rabbits using a Rose Bengal RVO model.
Methods :
The Rose Bengal laser-induced RVO model was performed on 8 New Zealand rabbit eyes. A custom-made, multimodal imaging system with a wavelength tunable pulsed laser (3-6 ns pulse duration, 1 kHz repetition rate, Ekspla NT-242, Lithuania), a scan lens, an ocular lens, and an ultrasonic transducer was integrated and coaxially aligned with a Thorlabs Ganymede-II-HR OCT. Retinal vascular dynamic changes were monitored and evaluated at 4, 28, 35, 42, and 84 days following laser-induced RVO, using the multimodal PAM and OCT imaging along with conventional color fundus photography and fluorescein angiography (FA).
Results :
In vivo experiments demonstrates that RNV developed in the rabbit RVO model at day 28 after photocoagulation, and the RNV was stable from 1 to 3 months (Figure 2). SD-OCT can identify the cross-sectional structure of RVO. PAM imaging characterized the location and the margins of the occluded vasculature as well as the morphology of individual RNV with high contrast and high resolution.
Conclusions :
The multimodality PAM-OCT system can precisely help visualize and distinguish individual retinal microvessels, their depth, and the surrounding anatomy. Thus, the proposed multimodal ocular imaging system may provide a potential imaging platform for improved visualization and characterization of retinal neovascularization diseases in a safe and efficient manner in future.
This abstract was presented at the 2019 ARVO Imaging in the Eye Conference, held in Vancouver, Canada, April 26-27, 2019.