High more defined cheekbones are possible if one has the right type of face for it. You would have to submit pictures of your face to get answer as to what may be possible for you.
Cheek implants are placed for patients who have a flat maxilla and flat cheek profile. Cheek implants are manufactured in a variety of sizes and shapes, are composed of Silastic, and are inserted through intr-oral approach under a brief general anesthetic as an outpatient surgical procedure. For many examples and more information, please see the link and the video below