A pilot study to image the vascular network of small melanocytic choroidal tumors with speckle noise-free 1050-nm swept source optical coherence tomography (OCT choroidal angiography)

To visualize and measure the vascular network of melanocytic choroidal tumors with speckle noise-free swept source optical coherence tomography (SS-OCT choroidal angiography).

Melanocytic choroidal tumors from 24 eyes were imaged with 1050-nm optical coherence tomography (Topcon DRI OCT-1 Atlantis). A semi-automated algorithm was developed to remove speckle noise and to extract and measure the volume of the choroidal vessels from the obtained OCT data.

In all cases, analysis of the choroidal vessels could be performed with SS-OCT without the need for pupillary dilation. The proposed method allows speckle noise-free, structure-guided visualization and measurement of the larger choroidal vessels in three dimensions. The obtained data suggest that speckle noise-free OCT may be more effective at identifying choroidal structures than traditional OCT methods. The measured volume of the extracted choroidal vessels of Haller’s layer and Sattler’s layer in the examined tumorous eyes was on average 0.982463955 mm³ /982463956 μm³ (range of 0.209764406 mm³ /209764405.9 μm³to 1.78105544 mm³ /1781055440 μm³). Full thickness obstruction of the choroidal vasculature by the tumor was found in 18 cases (72 %). In seven cases (18 %), choroidal vessel architecture did not show pronounced morphological abnormalities (18 %).

Speckle noise-free OCT may serve as a new illustrative imaging technology and enhance visualization of the choroidal vessels without the need for dye injection. OCT can be used to identify and evaluate the choroidal vessels of melanocytic choroidal tumors, and may represent a potentially useful tool for imaging and monitoring of choroidal nevi and melanoma.