Black specks in your dog's eyes can either be normal and not harmful, cause problems later down the road for your dog or indicate a disease such as cancer. There are certain things to observe that will help you determine whether you need to immediately bring your dog to a veterinarian ophthalmologist or if you can wait until the next checkup. Even benign tumors and cysts may need to be removed if they causes pain and vision loss.
Healthy eyes on a dog are shiny and bright, without any inflammation, swelling or discharge. Watery tears and mucus is normal if it is clear and minimal. It is normal to sometimes see your dog's third eyelid, a light membrane at the inside corner of the eyes, when it comes up to cover the eye when your dog goes to sleep. The whites of the eyeball should not have any coloring, especially yellow coloring.
Some eye pigmentation is normal. There are several things to look out for to help determine if the black specks are normal. If your dog has always had the black specks, it may just be a genetic trait. Normal pigmentation is confined to the iris, the colored part of the eye surrounding the pupil. If the black specks are a recent development, changes in size, location or shape, and if they have undefined edges, they may be an indication of a disease that requires urgent care by a veterinarian ophthalmologist. A veterinarian ophthalmologist's examination should also be immediately done if your dog shows other irregular symptoms or seems to be in pain. Even if the pigmentation looks normal, getting a veterinarian opthamologist's opinion is always best for your dog.
Melanoma or Melanocytoma
In some cases, black pigmentation in a dog's eye means the early stages of melanoma or melanocytoma. Melanocytes are cells that produce pigment called melanin. Melanocytes are found in many pigmented parts of the dog, including the eye. Sometimes, melanocytes develop abnormally and cause tumors. The tumor can be non-spreading (benign) or spreading (malignant). Benign tumors are clinically referred to as melanocytoma while malignant tumors are clinically known as melanoma, malignant melanoma or melanosarcoma. The most common tumors begin in the iris and are benign. While melanocytoma is in itself not harmful, it may cause pain and obstruct the dog's vision. Melanoma is rare. Only a veterinarian ophthalmologist can accurately diagnose your dog.
Black specks in the eye may also be iridal cysts. These small cysts are filled with fluid and are most common in Boston terriers, golden retrievers and Labrador retrievers. Some iridal cysts are attached to the iris or to the tissue behind the iris. Others are free-floating rather than fixed to a spot. Free-floating iridal cysts will always move to the bottom of your dog's eye. These cysts are not harmful and medical intervention is required only if they block your dog's vision. Fixed cysts should be seen by a veterinarian ophthalmologist immediately as they may actually be symptoms of melanoma.