waved asymmetric and irregular an injector assembly for injecting a microballoon into a subcutaneous pocket can include an injector having an elongated delivery portion with a delivery chamber where the delivery chamber has an outlet at least one microballoon is positioned in the injector structure can be provided for driving the microballoon through the outlet of the delivery chamber into the subcutaneous pocket in one embodiment an injector can be used to hold at least one microballoon 70 in a compressed position with a first compressed dimension and to release the microballoon when in the breast to permit the microballoon to expand to a second larger dimension in the subcutaneous pocket in this manner the microballoon 70 can be inserted into the subcutaneous pocket through a smaller incision one such injector 90 is shown in fig4 5 the structure for holding the microballoon 70 in a first compressed dimension can be any suitable structure but in one aspect is a compression chamber 94 into which the microballoon 70 is inserted the microballoon 70 when inserted in the compression chamber 94 assumes an elongated deformed shape indicated by phantom lines 70 a in fig4 the extent of compression can vary in the case of spherical microballoon 70 it is preferable that the microballoon be compressed to 1.