In the treatment of cancers, it is mainly 3 modalities that play important roles – surgery, radiotherapy and chemotherapy. While surgery in certain areas [like removal of part of the stomach or colon etc] do not need reconstruction, large defects following removal of tumors elsewhere, particularly in the region of the head and neck, will need reconstruction. This is particularly important to preserve important functions like speech, chewing and swallowing etc.
The need for reconstruction is based on an assessment of the likely functional and structural loss after major excisional surgery, which could be very mutilating and disabling without reconstruction. For example, in a person with a tumor of the tongue, a large excision may be needed, sometimes even including half the mandible [jaw bone]. Such a resection will inevitably leave a major disability in speech and swallowing unless a good reconstruction is done.
Reconstructive techniques have dramatically improved in the last 3 to 4 decades, thanks to a vastly improved understanding of anatomy and physiology as well as a quantum leap in operative techniques like microvascular surgery. Earlier, plastic surgeons were restricted in their repertoire by the availability of tissues in the vicinity of the excised defect, which was quite often inadequate or of poor quality, or both. However, all this has changed, thanks to “microvascular tissue transfer”. Essentially, this consists of safely and precisely removing tissues from elsewhere along with their blood supply, shaping and contouring them as required, transferring them to the defect and connecting the artery and vein to new blood vessels near the defect, thus providing a healthy and viable reconstruction immediately following the resection. Even complex and extensive resections can be and is commonly safely performed and reconstructed by such techniques with success rates of over 95 %. The donor sites [from where the tissues are taken] are chosen in such a way as to minimize the discomfort and morbidity that can arise from removal of tissues.
Tissue expansion, as a technique in plastic surgery, was a relatively new concept 4 decades ago, but is now fairly firmly established.
In essence, it is a technique that grew out of simple observation of a common event like pregnancy and practical application of the principle that all living things respond in a dynamic fashion to the mechanical stresses placed upon them!
In the medical world it was CG Neuman, in 1957, who was the first to expand skin by using an inflatable balloon. Radovan, after 2 decades, successfully expanded an arm flap using a temporary tissue expander. He used this to cover an adjacent defect after removal of a lesion.
Till then, the options for providing skin to cover defects were either to use skin grafts or flaps. Grafts are basically tissues, which are transferred from one part of the body to another.
Flaps, on the other hand, are tissues, which are transferred to neighboring skin regions while retaining some attachment to their parent area of origin.
While tremendous advances have been made in the understanding of anatomy and considerable sophistication has been achieved in the techniques for flap transfer, nevertheless the basic disadvantage of depriving one part of the body to provide for another part remains. In addition, there are issues pertaining to color and thickness mismatch, poor sensation and viability of the transferred skin. Tissue expansion, on the other hand, utilizes extra tissue generated by expanding normal skin, uses adjacent skin which most closely resembles the lost skin, and retains most of the sensation.
Essentially, the concept as well as the technique is fairly simple. When an expected skin defect [say, after removing a burn scar, birthmark or tattoo] cannot be adequately closed by suturing the adjacent margins together, a silastic bag of an appropriate size is buried in the plane below the adjacent normal skin in a surgical procedure. This is connected by a short piece of tubing to a small silastic dome called port, which is also usually buried under the skin a short distance from the bag. Once the surgical wound has healed, in about 2 weeks, the bag is inflated by injecting saline through the port at regular intervals, usually once or twice a week. The enlarging balloon slowly expands the normal skin and although some amount of thinning takes place, a considerable portion of the expanded skin is newly generated by the stress imposed on it. When the surgeon feels that enough skin has been generated, the bag and the port are removed, the lesion [scar, birthmark or tattoo as the case may be] is excised and the extra skin is advanced to close the wound.
Several expanders can be placed at the same time [this author has placed 5 at a time] in different areas so that time can be saved on the overall reconstructive procedure. Two types of expansion are recognized and used clinically today: prolonged tissue expansion (PTE), in which expansion occurs over 1-6 weeks, and rapid intraoperative tissue expansion (RITE), in which the expansion is performed cyclically in the operating room. Prolonged tissue expansion allows resurfacing of even wider defects with neighboring skin similar in color, texture, sensation, and retained adnexal structures like sweat glands and hair follicles. The uses of such a simple technique are obvious – the coverage of skin defects following excision of tumours, scar etc with good quality skin especially where there is need for specialized skin like the hair bearing scalp or for coverage of newly reconstructed organs like the ear etc. It is no surprise that the technique has found ready acceptance among reconstructive surgeons around the world.