Choroidal vascular circulation is critical to maintaining a healthy physiological environment to support normal vision. Dysfunctions in the choroidal vascular system contribute to several significant blinding diseases including macular degeneration. Noninvasive imaging can provide insight into the onset and progression of choroidal vascular dysfunctions and may lead to better understanding and treatment of macular degeneration. However, none of the existing retinal imaging technologies, including SD-OCT, SLO, autofluorescnece imaging, and fundus photography, can provide high-quality images of choroidal vascular system. We plan to test the feasibility of developing an indocyanine green (ICG) assisted photoacoustic ophthalmoscopy (PAOM) for high-resolution, three-dimensional imaging of choroidal vessels. In our proposed technology, short-pulsed near-infrared laser light will be absorbed by the ICG circulating in choroidal vessels. The choroidal vessels will then go through a temperature rise and a transient mechanical vibration to generate detectable ultrasonic wave. We will detect such ultrasonic waves to form a volumetric image of the choroidial vascular system. Compared with the existing ICG angiography, our proposed method requires lower ICG dosage due to stronger optical absorption of ICG than fluorescence and our proposed method will have higher resolution because ultrasonic is much less attenuated by the retinal pigmented epithelium and retinal neural fiber layer the fluorescent light. We already developed two PAOM systems in our lab. The requested fund from ISPB will provide support for animal experiments to collect preliminary data for an NIH grant application.
|Effective start/end date||7/1/12 → 6/30/13|
- Illinois Society for the Prevention of Blindness (Award Letter 7/24/12)