Abstract
Purpose :
To identify the diagnostic features of optic nerve head (ONH) melanocytoma on spectral domain optical coherence tomography (SD OCT) and OCT angiography (OCT-A) and to differentiate from similar pigmented choroidal lesions.
Methods :
Eleven consecutive patients clinically diagnosed ONH melanocytoma were analysed for their demographic (age, sex) and clinical details (size, colour, extent). All patients received multimodal imaging- fundus autofluorescence, SD OCT and OCT-A. Imaging features of choroidal melanoma and choroidal nevus reported in the literature were used for comparison.
Results :
The average age of patients was 52.8 +10.9 (range: 35-69) years, and there were 4 males. These tumors occupied 3-tissue spaces- optic disc (n=2), into retinal layer (n=5) and into retina-choroid layers (n=4). SD OCT (n=11) showed elevated hyper-reflective disorganized retinal layers with posterior shadowing (9 eyes), hyper-reflective dots within the tumor (all eyes) and in vitreous cavity (5 eyes). OCT-A (n= 8) showed abnormal tumor vasculature in the radial peripapillary capillary slab (7 eyes); intrinsic vascularity and increased flow rates in choriodal slab (all eyes). In nevus, the SD OCT showed intact outer retinal layers with a highly reflective choroidal layer underneath; OCT-A in choriocapillaries layer showed hypo-reflective areas with abnormal vascularity at boundary. In melanoma, SD OCT showed a high reflective choroidal layer with overlying photoreceptor irregularity; OCT-A showed abnormal vascularity both within and surrounding the lesion.
Conclusions :
SD OCT and OCT-A features help better understand structural and micro vascular changes in the ONH melanocytoma. They serve as valuable biomarkers to differentiate ONH melanocytoma from clinically similar looking entities like choroidal nevus and melanoma.
This is a 2020 ARVO Annual Meeting abstract.