Anterior segment optical coherence tomography of conjunctival nevus

To evaluate conjunctival nevi using anterior segment optical coherence tomography (AS-OCT).

Retrospective interventional case series.

There were 22 eyes of 21 patients with conjunctival nevus imaged with AS-OCT for evaluation and detection of cysts within conjunctival nevi.

Anterior segment OCT.

Evaluation and detection of intralesional cysts.

All margins of the nevus, including the deep margin, could be visualized on AS-OCT with high resolution of the anterior margin in 100% of cases, posterior margin in 82% of cases, and lateral margin in 86% of cases. The nevus was optically dense with homogeneous pattern in all cases. Some degree of deep optical shadowing, mostly from pigmented nevi, was noted in 86%. Intrinsic cysts within the nevus were detected by slit-lamp biomicroscopy in 18 cases (82%) and by AS-OCT in 17 cases (77%). In comparison with histopathologic findings, AS-OCT detected intrinsic cysts with a sensitivity of 80%, specificity of 100%, positive predictive value (PPV) of 100%, and negative predictive value (NPV) of 60%. Slit-lamp biomicroscopy (by experienced observers) compared with histopathology revealed detection of cysts with a sensitivity of 100%, a specificity of 100%, a PPV of 100%, and an NPV of 100%.

Anterior segment OCT provides high-resolution imaging of conjunctival nevi with the ability to demonstrate all margins and to provide information on the presence of intralesional cysts, which are important in the diagnosis. The main drawback is optical shadowing of deeper structures from pigment within nevi.