Notice the large, thinned posterior right globe, centered away from the optic disc.

Answer: Right globe staphyloma

This is commonly confused with a coloboma, which is a small, focal defect/lack of fusion of the choroidal fissure, ie at or near the optic disc

References

staphyloma: http://radiopaedia.org/articles/staphyloma

coloboma: http://radiopaedia.org/articles/coloboma