The eye shape is born to be what it is like. Generally, the shape will not change in essence with time flying. Sometimes people think their eyes look different than before because there are some factors of alteration. First, even the shape will no change, the size will change. The size of eyes refers to the size of palpebral fissure, which means the distance between upper and lower eyelids. When people grow old, their faces grow too. Thus, palpebral fissure becomes bigger. Meanwhile, the location of eyes in a face is also different. For infants, their eyes are almost in the middle of face, but for adults, there eyes are at about one third of face. So, eyes look different. Additionally, there will be some trace of age leave around your eyes, such as extra fat and wrinkles. They may bring you eye bags or black circles. They may squeeze your eyes and make them look smaller. All in all, this is no natural way to change the shape of eyes, it comes from gene. If you have to, plastic surgery is an option.
