Purchase this article with an account.
W. R. Freeman, A. S. Neubauer, U. Weber, B. Liesfeld; Retinal Navigated Laser Photocoagulation Using Eye Tracking and Registered Diagnostic Imaging With a Scanning Slit Ophthalmoscope (NAVILAS). Invest. Ophthalmol. Vis. Sci. 2009;50(13):2079.
Download citation file:
© ARVO (1962-2015); The Authors (2016-present)
To develop a navigating laser photo-coagulator for retinal disease. This device tracks retinal movement in patients and allows precise visualization of targeted laser treatment positions identified by angiography or fundus photography in a patient, allowing laser targeting and laser stabilization to the retina in a moving eye.
A digital ophthalmoscope, based on scanning slit technology was developed to provide continuous high-resolution digital imaging in color using white light illumination, infrared imaging and providing fluorescein angiography. A photocoagulation laser is integrated into the device emitting at 532 nm. Utilizing eye tracking from real-time imaging the position of the treatment laser can be adjusted to compensate eye motion. The diagnostic image can be registered and visualized on top of the real-time image. A software interface was designed to allow the clinician to view a fluorescein angiogram or color retinal image, identify lesions such as microaneurysms and enable a stabilized laser beam to track and photocoagulate selected lesions using eye tracking. An automated shut-off for the laser stops photocoagulation if the aiming beam enters a clinician defined block out zone (i.e. optic nerve head or foveal avascular zone). The system was tested using image sequences from human eyes with test subjects. Outcomes include the accuracy and the reproducibility of eye tracking and no treatment area shut off was tested. Initial patient experience in eyes with diabetic macular edema was evaluated.
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 was verified. Results from clinical work in eyes during laser treatment with diabetic macular edema will be reported.
The NAVILAS device allowed accurate imaging, registration to diagnostic imaging, particularly fluorescein angiography, and precise positioning and delivery laser photocoagulation burns in a navigable manner with eye tracking. Such a device will be useful for more accurate and safer ETDRS type treatment of diabetic macular edema and will also allow precise localization and treatment of non perfused peripheral retina in neovascular retinopathies which can be performed without significant visual loss.
This PDF is available to Subscribers Only