Method and system for in situ tissue expansion

Abstract

Tissue expansion system includes a pump, a controller, and inflatable bladder, and a pressure sensor. The pump is adapted for substantially continuous operation in response to a pressure within a subcutaneously implanted inflatable bladder. The pump is thus able to deliver inflation medium to the bladder when the pressure within the bladder is below a predetermined lower threshold while stopping delivery of the fluid when the pressure rises above a higher threshold or reaches a predetermined maximum volume.

What is claimed is: 
     
         1 . A system for expanding tissue, said system comprising:
 an expandable bladder adapted to be located beneath a region of skin to be expanded;   a pump adapted to be connected to a source of inflation medium and to deliver said inflation medium to the expandable bladder;   a pressure sensor adapted to monitor pressure within the expandable bladder on a substantially continuous basis;   a controller which receives pressure data from the pressure sensor and controls the pump to deliver inflation medium to the bladder when the pressure falls below a lower threshold value; and   a portable carrier which holds the pump, pressure sensor, and controller, wherein the portable carrier is adapted to be worn by a patient.   
     
     
         2 . A system as in  claim 1 , wherein the portable carrier comprises a vest, a backpack, or a belt. 
     
     
         3 . A system as in  claim 1 , wherein the controller is programmed to deliver inflation medium until the pressure reaches an upper threshold value. 
     
     
         4 . A system as in  claim 3 , wherein the upper threshold level is in the range from 5 mmHg to 35 mmHg. 
     
     
         5 . A system as in  claim 1 , wherein the controller is programmed to stop delivering inflation medium after a target total volume of inflation medium has been delivered to the patient. 
     
     
         6 . A system as in  claim 5 , wherein the target total volume of inflation medium is in the range from 150 cc to 800 cc. 
     
     
         7 . A system as in  claim 6 , wherein the target total volume of inflation medium is in the range from 200 cc to 600 cc. 
     
     
         8 . A system as in  claim 1 , wherein the expandable bladder is configured to be placed in a subpectoral pocket of the patient following a mastectomy. 
     
     
         9 . A system as in  claim 8 , wherein the expandable bladder is initially inflated with a volume of saline in the range from 50 cc to 100 cc. 
     
     
         10 . A system as in  claim 1 , wherein the controller is programmable. 
     
     
         11 . A system as in  claim 1 , wherein the controller is configured to control the pump to deliver the inflation medium, terminate delivery of the inflation medium, and resume delivery of the inflation medium after a predetermined interval. 
     
     
         12 . A system as in  claim 11 , wherein the predetermined interval is at least one hour. 
     
     
         13 . A system as in  claim 1 , wherein the inflation medium comprises saline.