Intraoperative Fluorescein Angiography Can Efficiently Identify Biomarkers and Guide Surgical Decision-Making

We sought to develop an efficient method for fluorescein angiography (FA) during digitally assisted vitreoretinal surgery (DAVS).

A 485-nm bandpass filter was placed into the filter holder of the accessory light sources of the Constellation Vision System with steel modified washers to produce an exciter source. A barrier filter was placed into the blank slot of a switchable laser filter with a 535-nm bandpass filter and another washer or created digitally with a specific color channel using NGENUITY software version 1.4. Fluorescein, 250 to 500 mg, was then injected intravenously during retinal surgery.

These fluorescence patterns accurately detect many fluorescein angiography biomarkers, such as determination of vascular filling times, ischemia, neovascularization, shunt vessels, microaneurysms, and leakage into the vitreous. This enhanced surgical visualization permitted intervention in real time such as laser or diathermy to residual microvascular abnormalities after delamination of retinal neovascularization as well as heavier panretinal laser placement in areas of retinal capillary dropout to relatively preserve areas of more intact retinal microcirculation.

The authors of this study are the first to report an efficient method that permits high-resolution detection of many classic FA biomarkers such as during DAVS to enhance surgical visualization and intervention in real time.