603887 A tissue retaining device includes a flexible suture thread having a surface microtexture and/or nanotexture. The height of the features is between 500nm and 10um. The surface microtexture and/or nanotexture filament is directional in that the resulting suture thread has a lower resistance to moving through tissue in the direction of intended deployment than in the reverse direction. A variety of alternative asymmetric textural elements and/or distributions of textural elements are disclosed. Methods for manufacturing the surface microtexture and/or nanotexture are also described.
