Clinical and ultrasound findings suggest a choroidal nevus that has remained stable over a decade of follow-up. Annual rate of malignant transformation 1 in 8845. Rate increases with age, and risk reaches 0.78% by 80 years old.
Risk factors for malignancy on ultrasound include:
- >2 mm in thickness
- subretinal fluid
- margin within 3mm of optic disc
- sonographic hollowness (rather than solid/fat)
- no drusen
Risk factors for malignancy on clinical examination:
- symptomatic
- orange pigment present
- absence of halo of depigmentation around lesion
- absence of drusen
Suspect uveal melanoma if:
- >2 mm thick and largest basal diameter >7 mm
- posterior acoustic shadowing
- spontaneous vascular pulsations