Canthus (kan’thus) refers to the inner & outer corners of the eye where the upper & lower eyelids meet. In cosmetic surgery canthoplasty involves placing a suture between the outside internal edge of the lower eyelid (canthal ligament) & the outside rim of bone surrounding the eyeball. This tightens the lower eyelid which becomes lax as part of the aging process. It is commonly performed together with cosmetic surgery of the lower eyelids & midfacelifts. When the laxity is very severe the ligament is divided & some portion of the lower eyelid is removed before placing the suture, a canthopexy.