| abstract |
The self-sealing tissue expander includes inner and outer layers of relatively nonflowable material and a median layer of flowable material, The median layer of flowable material which can include one or more sublayers of flowable material is under a predetermined compression imposed by the inner and outer layers due to a prestressing of the tissue expander shell during formation of the tissue expander. The self-sealing shell seals an opening in the shell wall following removal of an infusion needle. In all embodiments of the invention a needle stop member is provided to prevent the needle that accesses the fluid chamber from passing outwardly of the tissue expander. The need for a septum, a fluid conduit or a special fluid entry opening in the tissue expander shell is thus optional. The shell can also be made relatively more stretchable in some areas than in other areas. |