It may be associated with exophthalmos and lagophthalmos common in these dogs. (ackcsc.org)
Figure 2: This side - on (lateral) view of a dog's eye shows obvious protrusion of the eyeball or exophthalmos due to inflammation of the extraocular muscles (extraocular myositis). (vetmed.ucdavis.edu)
Although the extent of exophthalmos provides some clues as to the size and position of the orbital mass, an accurate assessment of where and how large the mass is requires advanced imaging techniques. (vetmed.ucdavis.edu)