Goniodysgenesis is a condition cause by the abnormal development of the eye which can result in excessive pressure buildup, eventually causing permanent damage to the optic nerve, resulting in blindness. Most forms of glaucoma can be placed into two categories, primary and secondary. The term primary glaucoma is used to describe those types of glaucoma caused by an inherited physical or physiological trait that an animal has been predisposed to. (Secondary glaucoma is a term referred to when the disease is triggered by something other than genetics.) Many dogs affected by glaucoma will become blind in the affected eye within the first year. Symptoms of glaucoma include: severe pain, sensitivity to light, winking spasms, sunken eyes, raised third eyebrow, dog winces when you touch the head, watery eyes, pain-related behavioral change (hiding, refusal to eat), red eye, and dilated pupils.