Abstract: XPAND Australia: A Multi-Center Evaluation of the Aeroform Patient Controlled Tissue Expander for Breast Reconstruction

Abstract

OBJECTIVE: A multi-center, prospective evaluation of the AeroForm Tissue Expander was performed to validate bench testing results following a device modification made to decrease the permeation and gradual loss of volume observed in earlier versions of the device. BACKGROUND: Previously reported results for the AeroForm Tissue Expander have demonstrated that the device can be used as effectively and safely as saline expanders to prepare the surgical pocket for breast implant placement following mastectomy. Modifications made to the device include a new material to form the inner liner which is designed to contain CO2 gas inside the expander. The permeation rate for the current device is improved to 0.3-0.4cc/day compared to previous versions which had a permeation rate of 2-4cc/day. The higher permeation rate in the previous version was observed clinically as a gradual loss of volume over time, particularly when implanted for > 6-months. These measurements were obtained via bench testing and this post-marketing study was undertaken to validate the results in-vivo. METHODS: Thirty (30) women were implanted with 50 AeroForm expanders; 20 bilateral, 10 unilateral reconstructions. Patients were followed prospectively from the time of implant, during the expansion process through the first post-operative visit after the exchange procedure. Success was measured based upon successful exchange to implant, days to complete the expansion process and the total length of time the expanders were implanted. Secondary endpoints measured were patient and physician satisfaction with the expansion process and the results of expansion. RESULTS: Twenty-six (26/30) patients completed their exchange with 4 patients awaiting an exchange date. Data is analyzed by breast with the primary endpoint defined as successful exchange to standard breast implant, precluding non-device related failures (100%). The median number of implant days is 93 with a range of 56–274 days. There have been no reports of gradual loss of volume over time or deflation. CONCLUSION: Results of the XPAND Australia post-marketing study confirm bench testing results which demonstrated an improved permeation rate of 0.4cc per day. The expander is labeled as a temporary implant (< 6-month implantation) but can be used successfully in patients undergoing chemotherapy and/or radiation who require longer implantation.