The lens of the eye is held in place by ligaments of a sort, called zonules (bands that attach the lens to the retina) and vitreous (fine fibers that hold the lens in place). When lens displacement takes place, the condition can cause pain or sometimes have no physical impact at all. However, the vision of your dog will always be affected. Lens luxation must always be addressed because of the risk of serious complications like glaucoma, or because the lens luxation could be the result of an underlying condition such as a tumor. A dislocated lens is often recognized as an inherited condition in the Terrier breed (Smooth, Wire Hair Fox, Jack Russell, Miniature Bull, Sealyham, Skye, Tibetan, Manchester, Scottish, and Welsh), and in Shar-Peis, Welsh and Cardigan Corgis, Collies, and the Brittany Spaniel.

Some canines may not show any symptoms of lens luxation; this can depend on the location of the dislocated lens. If you see that your dog is sticking closer to you and appearing to be looking for guidance or support, or if he is displaying any of the signs below a visit to the veterinary clinic is imperative.

In some instances, lens luxation is found only during a routine check up where the eye is examined (typically a posterior luxation as described below). It should be noted that lens luxation can occur in both eyes concurrently.

If a case of dislocated eye lens is left untreated, blindness can result. As well, your pet could be experiencing a fair amount of pain that you are not aware of. This is a condition  that must be dealt with as soon as possible in order to obtain the best possible outcome for retaining vision or avoiding further damage to the eye.

The veterinarian may be able to see that your canine family member has a dislocated eye lens by the clinical signs present upon first view; she will also take into consideration the breed disposition to lens mobility, the age of your dog and whether he has ocular problems already. 

Diagnostic tools that will give the veterinarian a closer look are the ophthalmoscope (viewing the back of the eye), the gonioscope (to look at the chamber between the iris and the cornea) and the tonometer (measures intraocular pressure). She may see the degeneration of vitreous strands and changes of symmetry within the eye chamber. The veterinarian will analyze the urgency of the situation (and it is most often urgent) due to complications like obstruction of fluid flow in the eye and retinal tears.

Treatment depends on whether the dislocated lens has moved to an anterior or a posterior position.

In the case of lens removal, a hospital stay is necessary. After the ophthalmologist feels that your pet can go home, he will be released with instructions to rest and stay quiet for several weeks. This means leash walks only and no running or jumping. Vision may be improved after the surgery, but the potential complication of retinal detachment or glaucoma is a reality.