Horses that have undergone cataract surgery to remove the damaged intraocular (inside the eye) lens now have more appropriate replacement lens options.

After cataract surgery horses are still able to see, but without inserting a replacement lens, they have abnormal vision. These aphakic (no lens) horses are unable to properly focus light on the retina, making images appear larger and less focused.

Brian Gilger, DVM, MS, Dipl. ACVO, a professor in the department of clinical sciences at North Carolina State University’s College of Veterinary Medicine, and colleagues surgically implanted 25-diopter (D) lenses into the four adult horses undergoing cataract surgery. The researchers then used retinoscopy and ocular ultrasonography to assess the lenses.

"We found that the 25-D lenses were too strong and overcorrected the eyes," noted Gilger. "Our data indicate that 18-D intraocular implants are more appropriate; however, more studies are needed to confirm this hypothesis