Abstract P2-13-06: Acellular dermal allograft fenestrations decrease outpatient expander fills and increase direct to implant incidence in implant-based immediate breast reconstruction
Authors: Daar DA , Bourgeois JM , Mowlds DS , Wirth GA , Paydar KZ 
Published: May 2016

Abstract
Introduction: The innovation of fenestrated allograft (acellular dermal matrix, ADM) has improved patient outcomes in two-stage tissue expander/implant breast reconstruction. This technical alteration utilizes optimal fenestration overlap and has enhanced the efficiency of the reconstructive experience. We present a follow-up study of one- and two-stage breast reconstruction with a more refined, standardized method of surgeon-designed fenestration of ADM.
Methods: We conducted a retrospective review of 52 patients (91 breasts) having undergone one- and two-stage breast reconstruction using fenestrated ADM at our institution from 2013 to 2014.
Results: Mean intra-operative fill volume (IOFV) measured 402cc (SD=118cc), and IOFV as a percent of tissue expander size averaged 79.1% (SD=16.7%). Ten breasts were expanded to 100% and completed reconstruction in one stage with implant placement. IOFV as a percentage of total fill volume at completion of expansion averaged 73.6% (SD=16.6%).
Two-stage reconstruction patients underwent 1.8 post-operative expansions on average (range 0-4) and averaged 81.2cc (SD=29.3cc) per in-office expansion. Days to full expansion averaged 45.1 days, while days to exchange averaged 137.8 days (Table 1). Mean days to exchange between our first 24 breasts to complete reconstruction vs. our last 23 breasts to complete reconstruction differed significantly, with 205 ± 43.8 days vs. 137.7 ± 138.1 days, respectively (p=0.03).
Table 1. Fill volume characteristics for 91 breasts after immediate reconstruction with fenestrated ADM. Data on tissue expander size was excluded.CharacteristicMinimumMaximumMeanSDTE size300700512.6108.3Intra-op fill (cc)150650402.1118Intra-op/TE size (%)44.1108.379.116.7Total fill (cc)31082537.6120.3Intra-op/Total fill (%)34.110073.616.6Total fill/TE size (%)76.9141.310813.2# of post-op expansions041.81.1Office fill per expansion (cc)31.322581.229.3Days to full expansion020445.141.8Days to exchange0554142117.9Implant size (cc)335800547.3126.9
The major complication rate requiring re-operation within 30 days post-operatively was 11.0%. Four breasts experienced partial mastectomy flap necrosis requiring re-operation with implant salvage (4.4%). Six breasts (6.6%) underwent explantation due to: infection (three), flap necrosis (two), and patient preference (one) (Table 2).
Table 2. Complication rates in 91 breasts after immediate reconstruction with fenestrated ADM.Complicationsn%Minor 30-day complication22.2Major 30-day complication1011.030-Day take back for necrosis with salvage44.430-Day explant66.6Explant due to infection33.2Explant due to necrosis22.2Explant due to patient preference11.1Total 30-day complication1213.2
Conclusion: Our fenestrated technique is demonstrated to increase intra-operative fill volume, decrease number of post-operative expansions and time to full expansion, and improve expansion rate with subjectively less pain. We believe our patients benefited from improved cosmetic outcomes with better shape, maintenance of breast footprint, and enhanced comfort due to the decreased number of intra-office fills and increased intra-operative expansion.
Citation Format: Daar DA, Bourgeois JM, Mowlds DS, Wirth GA, Paydar KZ. Acellular dermal allograft fenestrations decrease outpatient expander fills and increase direct to implant incidence in implant-based immediate breast reconstruction. [abstract]. In: Proceedings of the Thirty-Eighth Annual CTRC-AACR San Antonio Breast Cancer Symposium: 2015 Dec 8-12; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2016;76(4 Suppl):Abstract nr P2-13-06.