A canthoplasty is a specific type of plastic surgery procedure used to tighten a patient's lower eyelid. It falls under the general category of blepharoplasty, which is any surgical modification of the eyelids. This procedure, also known as inferior retinacular suspension, usually permanently alters the shape of the eye.
Performing a canthoplasty begins with severing the lower canthal tendon, which holds the lower eyelid in place. The tendon is then divided in two, and a new, tighter tendon is created and reattached to the orbital bone. This pulls the lower eyelid up and into the outer canthus, which is where the corners of the upper and lower eyelids meet.
This procedure is often sought after by patients looking for a more youthful shape to their eyes. People who suffer from drooping eyelids as a result of stroke or other other trauma also request this surgery. A canthoplasty can be performed for purely cosmetic reasons, and, done properly, can give the eyes a cat-like appearance. Often, canthoplasties are done at the same time as other facial cosmetic surgeries, such as an face or eyebrow lift.
Another common type of blepharoplasty is the canthopexy. This is similar to a canthoplasty and is often used as a synonym. A canthopexy, however, does not involve cutting the lower canthal tendon, but merely tightening it. The shape of the eye does not change when a canthopexy is performed.
Typically, a canthoplasty surgery takes between one and two hours to complete. Only local anesthetic is required, however, sedation or general anesthetic are also options. During the operation, a small incision is made in the outer corner of the eyelids so that the surgeon can access the tendon. When complete, any scarring should be concealed by the natural crease created by the canthus.
While the procedure has a low possibility of any serious side effects — such as blood clots, scarring, or infection — care must be taken to select an experienced and skilled surgeon. If performed incorrectly, a canthoplasty can result in deformation or retraction of the eyelids in the area of the canthus. This can present either immediately after surgery or several years in the future.
Also, patients must be clear about the realistic outcomes for the surgery. Canthoplasty can occasionally result in the opposite of the intended effect, meaning it can cause the eyelids to droop downward. In addition, if this procedure is performed on an individual with deep-set eyes and the tendon is over-tightened, it can result in an unnatural upward slant.