Image-Guided Retinal Therapy MIT Artificial Intelligence Lab, Brigham and Women's Hospital, and Scheie Eye Institute Retinal Image Registration We designed and implemented the registration algorithm for an ophthalmic augmented-reality prototype. The retinal-image on the left is a video image and the one on the right is an angiogram (showing blood-flow). Leaky blood vessels in the fovia are visible in the angiogram, but not in the microscope image. Augmented Reality Visualization Laser therapy is commonly used to treat leaky blood vessels. However, the surgeon cannot clearly see the affected regions directly through the microscope. The edges from the angiogram (shown in green) are exactly registered and overlaid on top of the video image. The augmented-reality display is visualized through a Zeiss slit-lamp biomicroscope. Retinal Image Montaging An a priori retinal image mosaic is constructed to form the vessel model. Multiple images are acquired and registered to form one coherent montage (left). The edges are found to highlight the vessels which will be included in the augmented-reality visualization (right). Patent "Technique for creating an ophthalmic augmented reality environment."         Jeffrey Berger, Michael Leventon, Ron Kikinis.         Patent # US-5912720