No, it is not the samething as a freckle or mole on the eye though I am not sure what he meant by pigment clusters on the optic nerve. He probably was referrring to choroidal sclerosis or myopic crescent around the optic nerve. You do not need to worry about these 2 things though. However, you should see an ophthalmologist for a dilated eye examination to ensure that this is what he meant. Thanks and best wishes.
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