gms | German Medical Science

Purpose: To develop and investigate a navigating laser photo-coagulator for retinal disease. This device tracks retinal movement in patients and allows precise visualization of targeted laser treatment positions, allowing laser targeting and laser stabilization to the retina in a moving eye.

Methods: A novel digital ophthalmoscope provides continuous high-resolution color or infrared imaging and provides fluorescein angiography (FA). Real-time eye tracking can compensate eye motion for the integrated 532nm laser. A diagnostic image can be visualized on top of real-time imaging. An automated block out zone can be defined by the physician and shuts off laser photocoagulation if entering the zone. The system was tested using model eyes and using image sequences from human eyes with test subjects. Outcomes included accuracy and reproducibility of eye tracking and investigating the shut-off function. Initial patient experience in eyes with diabetic macular edema was evaluated.

Results: More than 95% of all images analyzed were tracked with an accuracy of better than 100 µm. The reliability of blocking the treatment laser in case of tracking failure could be verified. Results from clinical work in eyes during laser treatment with diabetic macular edema will be reported.

Conclusions: The NAVILAS device allowed imaging, registration to diagnostic imaging (such as FA), and precise delivery of laser photocoagulation with eye tracking. Such a device will be useful for more accurate and safer ETDRS type treatment in macular edema and will also allow precise localization and treatment in other retinal disease.