Background
The advantages of dual plane, partially submuscular breast implants are well documented.  These advantages include decreased rates of capsular contracture, improved upper pole fullness, decreased palpability and visibility of implants and improved breast aesthetics in cases where the soft tissue envelope is inadequate to support subglandular implants.  Standard conversion techniques to dual-plane positioning utilize marionette sutures and internal capsulorrhaphy sutures from the lower edge of the pectoralis major muscle to the anterior capsule or breast fascia within the subglandular plane.  These techniques are limited by high rates of post-operative implant malposition and technical limitations that make combined mastopexy procedures difficult to perform.  We describe a simple technique familiar to most plastic surgeons accustomed to placing tissue expanders for use in breast reconstruction using Alloderm® as a sling beneath the pectoralis major muscle to the chest wall.
Methods
We retrospectively studied 25 women who underwent breast augmentation revision from subglandular to the dual plane position by performing a 9-year retrospective review from 1999-2007 of two surgeons’ experience.  We identified 10 women for whom Alloderm®, sutured from the lower edge of the pectoralis major muscle to the chest wall was used to create a composite pectoralis-Alloderm® pocket for partial-submuscular transfer of implants, and identified 15 matched case-controls who underwent pocket conversion using standard capsulorrhaphy and marionette suture techniques.  Dependent variables analyzed included post-op capsular contracture, pain, infection, and requirement of revision.  Statistical analyses were performed using STATA Software (College Station, TX).  Data analyzed included patient age, size and type of implants, duration from previous surgery, palpability, capsular contracture, seroma, implant pocket-displacement, pain, IMF discrepancy, need for mastopexy, OR time, and duration of follow up.  Fisher’s Exact Test was used for comparisons of contingency tables.  T-test was used to compare mean OR times. 
Results
The average patient age was 42 (29-56) years, the average implant size was 323 cc (range 200 cc - 500 cc) and 74% of pocket-change patients also sought a size-change.  For the size change, 61% sought an increase and 39% sought a decrease in size.  Indications for seeking revision were palpability (48%), capsular contracture (70%), and rupture (26%), which were not related to silicone or saline implants (Fisher’s Exact test, p=0.4).  The principal outcome variable of at least one complication was 73.3% without Alloderm® resulting in a 40% need for revision surgery vs. 0% with Alloderm® (Fisher’s Exact test, p<0.05).  There were no seromas and only 1 superficial infection in the non-Alloderm® group.
Conclusions
            The standard techniques available for conversion of subglandular breast implants to the dual-position plane using capsulorrhaphy and marionette sutures are limited by a high complication rate for the reliable positioning of implants into a stable dual-plane pocket during implant exchange.  A commonly utilized technique in reconstructive breast surgery using Alloderm® is described to reliably convert subglandular implants to the dual plane position.