Optical coherence tomography angiography characteristics of optic disc melanocytoma

Abstract

Background Optic disc melanocytoma (ODMC) was a benign pigmented intraocular tumor with the rare potential malignant transformation. This study was designed to evaluate tumor vasculature with optical coherence tomography angiography (OCTA) in ODMC. Methods Eyes of healthy individuals in a control group and of patients with ODMC were imaged by OCTA systems operating at 840 nm wavelengths and examined. The main outcome measures were OCTA images, qualitative evaluation of optic disc and tumor vasculature, quantitative vascular density (VD) and perfusion density (PD). Results One eye of ten normal volunteers and ten patients with ODMC were imaged. Eyes affected by ODMC as compared to the eyes of the control group (all P < 0.05). The healthy optic disc had radially-oriented vessels within the retina on OCTA. Optic disc melanocytoma was characterized by globular, demonstrated tortuous blood vessels, uneven thickness, and relatively disorganized intratumoral vasculature. The VD and PD within ODMC were significantly higher (12.360% ± 4.175, 0.316% ± 0.119%, P < 0.0001) than in normal optic discs (4.160% ± 2.290, 0.102% ± 0.0, 56%, P < 0.0001). No significant differences were established of the VD and PD in each single measurement zone (P > 0.05) between the ODMC and the control eyes. At 840 nm, OCTA could provide sufficient visualization of the tumor vasculature and better penetration through thicker tumors. The full thickness was visualized even in thicker tumors and highly pigmented lesions (> 2 mm). Interpretable OCTA images were obtained in 96% of the participants in whom imaging was attempted. Conclusions OCTA may provide a noninvasive, safe, and efficient technique for evaluating a variety of neoplasms including the growth and vascularity in ODMC. OCTA could facilitate the evaluation of the vascular abnormalities of tumors and the effect of melanin on the penetration of the OCTA beam was not significant.

Evaluation of blood vessel network formation and visual field defect in optic disc melanocytoma

“… 31 According to one previous study, OCTA operating at 840 nm wavelength could visualise the full thickness of pigmented ODM in the range of 0.72–2.13 mm. 32 However, all of the tumours in this study were evaluated with OCTA operating at 870 nm wavelength and showed thickness within the above range except for only one case, which showed a thickness of 2.21 mm. Therefore, most of the tumour vasculature included in this study was well visualised by OCTA.…”

Melanocytoma of the Optic Nerve- A Case Report

“…Optic Nerve Melanocytoma (ONM) is a rare benign pigmented tumor and could be progressive and malignant in about 1-2% of cases 1,2 . Intraocular pigmented lesions can occur from melanocytes in the uvea or pigmented epithelium in the retina, ciliary body, and iris 3 .Sometimes it is difficult to distinguish ONM from malignant melanoma, however, most patients are asymptomatic with no vision loss 1,3 . Although ONM has a very low chance of malignancy, it has been previously reported that patients with intraocular melanocytic lesions have been enucleated based on suspicion of melanoma 5 .…”