Back-to-Front Flipping of Implants Following Augmentation Mammoplasty and the Role of Physical Characteristics in a Round Cohesive Gel Silicone Breast Implant: Retrospective Analysis of 3458 Breast Implants by a Single Surgeon

Abstract

Augmentation mammoplasty is one of the most commonly performed procedures today by plastic surgeons. Results and outcomes of the procedure depend on appropriate prosthesis selection, pocket selection, and pocket dissection. Available pockets are subglandular [1], partial submuscular [2], dual plane [3], subfascial plane [4], and muscle-splitting biplane [5]. On the other hand, implant selection is not easy due to the multitude of available implant shapes, sizes, texturing, gel-fill ratios, and profiles. The choice may run into thousands when all of the available products of various manufacturers are added. Fewer available pockets and familiarity with them makes it easier to select a pocket; however, the battle to select and find an ideal implant is far from over. Comparative parity between the breast width and the implant dimension is of paramount importance regardless of the physical characteristics of an implant or pocket. However, the fine details of the result are in the interaction between breast envelopes, physical characteristics of the implant, and a carefully dissected pocket. The two most commonly used implant fillers are saline and silicone. These implants may have a smooth, microtextured, or textured surface and are available in an anatomical shape, with low, moderate, high, and extra high profiles with different gel-fill ratios. As opposed to the subpectoral plane used for saline implants, silicone implants can be placed in either subglandular or subpectoral pockets, depending on the soft tissue characteristics of the breast envelope. The criterion of envelope adequacy usually is measured by a pinch test [3], although the longterm reliability of the pinch test needs to be carefully assessed [6]. The malposition of the implant is one of the known and common complications seen following mammoplasty. Asymmetries secondary to malpositioning are generally attributed to overdissection of the pocket or displacement of the implant. The presentations and mechanisms behind these deformities are many, but the preservation of anteroposterior orientation of the prosthesis is almost always undisturbed [7]. The deformity due to a change in the anteroposterior orientation of a round cohesive gel implant is a complication that depends on the presence or absence of texturing, the shape/profile of the implant, and its gel-fill ratio. The severity and degree of the deformity associated with malorientation can be more noticeable with anatomical implants than with round, soft, cohesive gel silicone implants; this is due to the permanent three-dimensional shape of the anatomical implant [8]. Since the introduction of silicone implants with polyurethane foam texturing [9], texturing of implants has continued to be popular because of the resistance to capsular formation that it provides [10]. Texturing of an implant is in the form of depressions or nodules. The physical characteristics and effectiveness of these nodules and depressions depend on pore diameter, depth, and density, which allow the fibrous capsule to grow into the pores on the shell. In reality, the pore sizes and texturing appear as a mirror image on the interface of the capsule when seen under the electron microscope [11]. The proper fit of a textured implant into its surrounding pocket and ingrowth of fibrous tissue into the pores prevent micromovement, whereas a smooth or microtexture-surfaced implant may not be able to adhere to the capsule, allowing for micromovements and resulting in synovial metaplasia [12, 13]. Synovial metaplasia contributes to the instability U. D. Khan (&) Re-shape House, 2-4 High Street, Westmalling, Kent ME19 6QR, UK e-mail: Mrumarkhan@aol.com