Elsevier

Ophthalmology

Volume 118, Issue 6, June 2011, Pages 1119-1124
Ophthalmology

Original article
Clinical Evaluation and Treatment Accuracy in Diabetic Macular Edema Using Navigated Laser Photocoagulator NAVILAS

Presented in part at: American Academy of Ophthalmology Annual Meeting, 2009, San Francisco, California.
https://doi.org/10.1016/j.ophtha.2010.10.007Get rights and content

Purpose

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.

Design

Interventional case series.

Participants

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.

Main Outcome Measures

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.

Financial Disclosure(s)

Proprietary or commercial disclosure may be found after the references.

Section snippets

Patients

This was an interventional case series of 86 eyes of 61 patients (32 women, 25 bilateral treatments) with diabetic retinopathy treated with the NAVILAS. The patients were enrolled and treated at the following institutions: Jacobs Retina Center at the University of California, San Diego, in La Jolla, California, and Instituto de Sub-Especialidades Oftalmologicas A.C. in Tijuana, Baja California, Mexico. Institutional review board approval was obtained at both sites. Four eyes of 4 patients

Results

This was a consecutive case series of eyes treated with the NAVILAS system. The diagnoses for which laser photocoagulation was used included clinically significant DME and extramacular diabetic retinopathy (86 eyes). The visual acuity of enrolled eyes ranged between 20/40 and 20/400.

Discussion

Retinal laser photocoagulation as a standard of care has been performed manually using a slit lamp. For precise photocoagulation, a contact lens system with anesthesia is necessary, and laser treatment is performed under bright white light illumination. Precision treatment of microaneurysms such as that prescribed by the ETDRS protocol is difficult and requires projecting a good-quality angiographic image and having the retina specialist attempt to locate each aneurysm seen on the angiogram on

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Cited by (0)

Manuscript no. 2010-864.

Financial Disclosure(s): The author(s) have made the following disclosure(s): William R. Freeman - Consultant - OD-OS GmbH. Dennis Dowell - Employee - OD-OS GmbH.

Supported in part by the University of California San Diego, La Jolla, California; and by an unrestricted grant from Research to Prevent Blindness, Inc., New York, New York.

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