This pug has been brought to you as the owner is worried about his eyes – what can you see – and perhaps more importantly for animal and owner what can he see?!
A closer view shows superficial pigment at the medial canthus with a white halo of inflammatory cells. The Schirmer tear test reading here is 16mm/minute so the problem is not related to a deficiency in tear production, but the dog only blinks once every minute or so, and tear film evaporation, together with some medial entropion is probably the cause of the pigment migration.
Just about every pug one sees over the age of three or four has this sort of pigment migration, sometimes quite substantial as shown below.
In such cases as this vision will be compromised when the pupil is miotic, but a superficial keratectomy will most likely result in yet more pigment. An early canthoplasty surgery to reduce the width of the palpebral aperture is probably what is needed prophylactically before the pigment develops.