A pilot study to compartmentalize small melanocytic choroidal tumors and choroidal vessels with speckle-noise free 1050nm swept source optical coherence tomography (OCT choroidal "tumoropsy").

Abstract

The purpose was to illustrate small melanocytic choroidal tumors with speckle-noise free swept-source optical coherence tomography (SSOCT). Twenty-five small melanocytic choroidal tumors in 24 eyes underwent 1050nm OCT. All tumors were measured manually with the built-in caliper tool and compared to data derived from a semiautomated algorithm that removed speckle noise but preserved the structure of the tumors from the SSOCT data. The average manual measurements for the horizontal, vertical, and axial diameters were 1535.28μm (range, 547-2807μm), 1713.8μm (range, 574-3921μm), and 227.28μm (range, 115-489μm), respectively. The measured average volumes of the tumors were 835,248,212μm(3) (range, 48,818,700 to 4,567,401,810μm(3)) and 228,588,535μm(3) (range, 22,879,641 to 787,668,886μm(3)) for caliper measurements, respectively, for the extracted volumes. The average volume variation between the two methods was 66.16% (range, 46.5% to 82.75%). The average ratio between the caliper and extracted volumes was 3.402 (range, 1.346-8.198, SD 1.681), 2.367 (range, 1.346-3.258, SD 0.618), 2.321 (range, 1.346-3.258, SD 0.611), 2.402 (range, 1.518-3.258, SD 0.591), and 1.749 (range, 1.518-1.733, SD 0.239) for all tumors, all tumors with the exclusion of extreme parameters, tumor <3mm, tumor <2mm, and tumor <1mm, respectively. The average ratio (tumor index) between the tumor volume and the choroidal vessel volume was 12.539 (range, 0.489-73.701). Speckle-noise free swept-source OCT may be an illustrative OCT imaging technology. OCT may be useful for describing and monitoring small melanocytic choroidal tumors and the choroidal vessels.