Patent ID: 8874234

Claim:
An implantable device comprising: a structure made of a material selected from silicone, polyurethane and combinations thereof and having a surface facing surrounding tissue when the implantable device is implanted in a subject body; wherein at least a portion of the surface of the structure has a semi-random pattern of extending micropillars where the coordinates of a micropillar number i on the surface are defined as (x i , y i )=(x i 0 +α i +ζ×s, y i 0 ×β i ζ×S) wherein α i , β i are random numbers within a range of 0 to 1, S denotes an average interpillar spacing in the semi-pattern of micropillars, ζ is within a range of 0.5 to 0.7 and (x i 0 , y i 0 ) indicates the coordinates of the micropillar number i in a perfectly ordered array of extending micropillars with interpillar spacings equal to S.