Clinical evaluation and treatment accuracy in diabetic macular edema using navigated laser photocoagulator NAVILAS.
OBJECTIVE
To evaluate the clinical use and accuracy of a new retinal navigating laser technology that integrates a scanning slit fundus camera system with fluorescein angiography (FA), color, red-free, and infrared imaging capabilities with a computer steerable therapeutic 532-nm laser.


METHODS
Interventional case series.


METHODS
Eighty-six eyes of 61 patients with diabetic retinopathy and macular edema treated by NAVILAS.


METHODS
The imaging included digital color fundus photographs and FA. The planning included graphically marking future treatment sites (microaneurysms for single-spot focal treatment and areas of diffuse leakage for grid pattern photocoagulation) on the acquired images. The preplanned treatment was visible and overlaid on the live fundus image during the actual photocoagulation. The NAVILAS automatically advances the aiming beam location from one planned treatment site to the next after each photocoagulation spot until all sites are treated. Aiming beam stabilization compensated for patient's eye movements. The pretreatment FA with the treatment plan was overlaid on top of the posttreatment color fundus images with the actual laser burns. This allowed treatment accuracy to be calculated. Independent observers evaluated the images to determine if the retinal opacification after treatment overlapped the targeted microaneurysm.


METHODS
Safety and accuracy of laser photocoagulation.


RESULTS
The images were of very good quality compared with standard fundus cameras, allowing careful delineation of target areas on FA. Toggling from infrared, to monochromatic, to color view allowed evaluation and adjustment of burn intensity during treatment. There were no complications during or after photocoagulation treatment. An analysis of accuracy of 400 random focal targeted spots found that the NAVILAS achieved a microaneurysm hit rate of 92% when the placement of the treatment circle was centered by the operating surgeon on the microaneurysm. The accuracy for the control group analyzing 100 focal spots was significantly lower at 72% (P<0.01).


CONCLUSIONS
Laser photocoagulation using the NAVILAS system is safe and achieves a higher rate of accuracy in photocoagulation treatments of diabetic retinopathy lesions than standard manual-technique laser treatment. Precise manual preplanning and positioning of the treatment sites by the surgeon is possible, allowing accurate and predictable photocoagulation of these lesions.


BACKGROUND
Proprietary or commercial disclosure may be found after the references.
Jacobs Retina Center, Department of Ophthalmology, University of California, San Diego, La Jolla, California 92037, USA.
Igor
I
Kozak
Stephen F
SF
Oster
Marco A
MA
Cortes
Dennis
D
Dowell
Kathrin
K
Hartmann
Jae Suk
JS
Kim
William R
WR
Freeman
D003930:Diabetic Retinopathy / Q000150:complications / Q000175:diagnosis / Q000601:surgery*; D004867:Equipment Design; D005260:Female; D005451:Fluorescein Angiography; D005654:Fundus Oculi; D006801:Humans; D017075:Laser Coagulation / Q000295:instrumentation*; D008266:Macula Lutea / Q000187:drug effects / Q000473:pathology*; D008269:Macular Edema / Q000175:diagnosis / Q000209:etiology / Q000601:surgery*; D008297:Male; D015203:Reproducibility of Results; D016896:Treatment Outcome