Panretinal Laser Photocoagulation (PRP) using the slit-lamp is a widely used treatment for sight-threatening retina diseases. It is a challenging procedure, therefore a number of mapping techniques have been proposed to provide surgeons with reliable intra-operative navigation assistance and mapping. However, available methods are limited by tracking errors, caused by lens distortions, illumination variations and abrupt patient movement. To handle these issues, we propose a strategy for non-rigid fine adjustment of retina maps acquired using the slit-lamp. We describe a novel direct framework for alignment of multiple overlapping images via a Thin-Plate Spline model. Our method is able to cope with illumination variations between overlapping images and does not require a priori geometrical information. Experiments conducted on maps acquired from several human patients attest the method's ability to correct ghosts and blurring, improving the consistency and accuracy of the maps.
['Rodrigo T. F. Linhares', 'Rogério Richa', 'Ricardo de Moraes', 'Antonio Carlos Sobieranski', 'Aldo von Wangenheim']
Non-rigid Fine Adjustment of Retina Maps Acquired Using a Slit-Lamp