Motion Signal Detected in Cystic Spaces on Optical Coherence Tomography Angiography

Abstract

Purpose : To detect decorrelation signal within cystic spaces on optical coherence tomography (OCT) angiography.

Methods : Macular scans of participants with diabetic macular edema (DME) and neovascular aged related macular diseases (AMD) were taken using a spectral OCT system (RTVue-XR). The split-spectrum amplitude-decorrelation angiography (SSADA) algorithm was applied to detect flow. Semi-automated segmentation was used to identify the outer retina. The maximum flow projection in this slab was used for grading the decorrelation signal within cysts.

Results : 64 eyes of 37 patient with diabetic retinopathy and 57 eyes of 57 patients with neovascular AMD were analyzed. Of these, 5 eyes of 4 patients with diabetes had decorrelation signal within intraretinal cysts and no eyes with AMD. Patients with decorrelation signal had a mean central macular thickness of 341± 74.5 microns. Two patients had been treated with focal laser and anti-VEGF therapy. These cysts were sometimes associated with adjacent lipid and were most commonly in the parafoveal region. The decorrelation was noted in smaller cysts and not in large cystic spaces.

Conclusions : We present the first report of decorrelation signal within cysts. Previously all decorrelation signals had been attributed to flow within vessel or artifacts. The decorrelation signals within cysts likely originate from moving particles. These particles could be lipid or protein exudates, or cells. They tend to be present in smaller cysts in diabetic retinal edema, and not in fluids associated with choroidal neovascularization.

This is an abstract that was submitted for the 2016 ARVO Annual Meeting, held in Seattle, Wash., May 1-5, 2016.

 

(A) En face OCT angiogram with cystic motion (B) Quantification of cystic spaces with detected decorrelation (C) Cross sectional angiogram showing intravascular flow in purple and cystic motion in blue.