A mammary implant and method of making are provided herein. The implant includes an outer shell configured to retain fluid therein, an injection element coupled to the outer shell and adapted to receive therethrough an injection device for injecting fluid into the outer shell, and an injection marker zone made of a material having ultrasonically detectable markers incorporated therein. The markers are a plurality of microcavities that are located relative to the injection element so that, when ultrasonically detected, such detection indicates a location of the injection element.