If the dust particle is moving even after stoppage of eye movements that means it is floater means vitreous opacities moving here and there on eye movement. It is normal phenomenon but if it is happening with flashes of light then you must consult retinal surgeon urgently otherwise just relax.normal floater is not harmful.when it obstructs your vision then just move your eyes,it will move aside.
Answered2016-06-30 15:55:32
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