Tissue expansion has long had a critical role for patients considering options for breast reconstruction following mastectomy. In recent years, many of the most popular tissue expanders have resembled full or moderate height permanent implants with an anatomic shape. The more recent introduction of low height variable projection tissue expanders in many ways represents a return to the earliest tissue expander designs having a crescent shape. This study seeks to report a large experience of consecutive patients who underwent tissue expansion following mastectomy using low height variable projection tissue expanders, with emphasis on the ability of these devices to help control shape in breast reconstruction.

METHODS: 172 consecutive patients underwent placement of 246 tissue expanders. All expanders used were McGhan Style 133LV (Inamed Corporation) low height variable projection or Mentor Low Height Contour Profile (Mentor Corporation) devices. 105 patients underwent unilateral reconstruction. 67 patients underwent bilateral expander placement. All expanders were placed in a submuscular pocket, with the base of the device in a subcutaneous plane in the area of the inframammary fold. The devices were routinely placed with no fluid added at the time of mastectomy, with the base of the device closely conforming to the inframammary fold shape. Expansion was started routinely 4-6 weeks following device placement and was repeated every other week until adequate device capacity was reached. All patients included in the study had either completed their course of expansion with permanent implant placement, or had a complication requiring expander replacement or removal.

RESULTS/COMPLICATIONS: Overall, complications were seen in 18 patients (10%). Complications occurred as follows: Malposition 6 (3.5%) Infection 7 (4%) Rupture 3 (1.8%) Extrusion (traumatic) 1 (0.6%) Capsular contracture 1 (0.6%).

The patients with malposition, rupture, and capsular contracture each underwent replacement with another device of the same type. Four of the seven patients with infection required device removal, one of whom underwent delayed device replacement. The patient with traumatic extrusion underwent expander removal with no replacement.

CONCLUSIONS: Shape control using low height tissue expanders results from a design that allows for the expansion process to be targeted to the lower pole of the breast, where projection is needed most for optimal aesthetic outcome. This allows for minimal expansion in the middle and upper areas of the breast that can preserve tissue thickness to lessen the chance for permanent implant folds and flaws to become apparent. Placement of the device with no fluid, with the base of the device closely conforming to the curve of the inframammary fold, allows for increased control of inframammary fold shape. Low height tissue expanders have low fill capacities that can allow for fewer injections during the expansion process and more appealing shape that can make the expansion process more easily tolerated in breast cancer patients.