Optical coherence tomography enhanced depth imaging of choroidal tumors

To describe the spectral-domain optical coherence tomography (SD-OCT) features of choroidal tumors imaged using enhanced depth imaging (EDI) technique.

Prospective observational case series.

One tumor each from 23 eyes of 23 patients was included. All the patients underwent clinical fundus photography, ultrasonography, and EDI SD-OCT. Qualitative characteristics (tumor outline, reflectivity and/or shadowing of choroidal layers, and detection of inner sclera) and quantitative characteristics (measurement of maximum tumor thickness and the largest tumor diameter) were assessed.

Patients (male=12) were categorized as: amelanotic choroidal nevus (4), melanotic choroidal nevus (9), choroidal melanoma (3), circumscribed choroidal hemangioma (3), and choroidal metastasis (4). In all cases, EDI SD-OCT was able to identify the tumor distinctly from the surrounding normal choroid. Qualitative analysis revealed: amelanotic nevi, homogenous and medium reflective band with visible choroidal vessels; melanotic nevi and choroidal melanomas, high reflective band in the anterior choroid with shadowing, and nonvisualization of choroidal vessels and inner sclera; choroidal hemangiomas, medium/low reflective band without shadowing; and choroidal metastasis, low reflective band in the deep choroid with enlargement of the suprachoroidal space. Maximum tumor diameter and thickness was measurable by EDI SD-OCT only in 10 cases that were <9.0 mm in diameter and <1.0 mm in thickness (undetectable by ultrasonography).

It is possible to obtain cross-sectional views of a variety of choroidal tumors using EDI SD-OCT. Small choroidal tumors nondetectable by ultrasonography can be objectively measured by this technique.