Second generation self-inflating tissue expanders: a two-year experience

The Use of Self-Inflating Hygroscopic Tissue Expanders to Facilitate Osteosarcoma Removal in a Massasauga Rattlesnake (Sistrurus catenatus)

A 0.34 kg adult female Massasauga rattlesnake (Sistrurus catenatus) was presented for evaluation of a subcutaneous mass affecting the ventral scales. The mass was diagnosed as a sarcoma via punch biopsy with no evidence of metastasis on diagnostic imaging. Surgical margins of 1-2 cm were planned to achieve complete excision of the neoplasm. A technique for tissue expansion was employed due to concerns regarding the ability to close the surgical site without excess tension or dehiscence. Two 27 mm diameter × 5 mm hygroscopic self-inflating tissue expanders were placed subcutaneously under the lateral scales adjacent to the mass. Maximum skin expansion occurred over a four-week period, and no direct negative effects were noted. Excision of the primary mass was performed routinely five weeks after implant placement. Primary closure of the defect was achieved with minimal tension by incorporating the expanded skin. While the surgery was successful with no evidence of metastasis, the snake died of sepsis two weeks postoperatively. This is the first report of the use of self-inflating hygroscopic tissue expanders to help close a surgical defect in a reptile.

Hydrogel Tissue Expanders for Stomatology. Part II. Poly(styrene-maleic anhydride) Hydrogels

Self-inflating soft tissue expanders represent a valuable modality in reconstructive surgery. For this purpose, particularly synthetic hydrogels that increase their volume by swelling in aqueous environment are used. The current challenge in the field is to deliver a material with a suitable protracted swelling response, ideally with an induction period (for sutured wound healing) followed by a linear increase in volume lasting several days for required tissue reconstruction. Here, we report on synthesis, swelling, thermal, mechanical and biological properties of novel hydrogel tissue expanders based on poly(styrene-alt-maleic anhydride) copolymers covalently crosslinked with p-divinylbenzene. The hydrogels exerted hydrolysis-driven swelling response with induction period over the first two days with minimal volume change and gradual volume growth within 30 days in buffered saline solution. Their final swollen volume reached more than 14 times the dry volume with little dependence on the crosslinker content. The mechanical coherence of samples during swelling and in their fully swollen state was excellent, the compression modulus of elasticity being between 750 and 850 kPa. In vitro cell culture experiments and in vivo evaluation in mice models showed excellent biocompatibility and suitable swelling responses meeting thus the application requirements as soft tissue expanders.

Tissue expansion reconstruction of head and neck burn injuries in paediatric patients - A systematic review

Tissue expansion reconstruction in clinical practice has existed for over half a century. The technique was initially used for breast reconstruction but later found its use in reconstruction of excisional defects resulting from a variety of causes including surgery for post-burn/post-traumatic deformities, congenital giant naevi, skin cancer, etc. It offers an improved matching of skin colour and texture, and avoids the high infrastructure requirements of microsurgery for free flap transfers. We present a systematic literature review of 35 worldwide English language articles with representative cases of paediatric tissue expansion reconstruction of burn injuries of the head and neck. The review identified 68 children of an average age of 11.3 years. The most common burn aetiology was flame burn injury. The average area to be reconstructed was of 206 cm2 and patients went through expansion processes for an average of 99.7 days. Three articles included cases in which patients had more than one expansion session. Supportive techniques provide examples of developments in the area of tissue expansion reconstruction such as self-inflating expanders and endoscopic approaches. Further studies focussing on particular indications, age groups and anatomical locations of tissues to be expanded are required in order to improve the understanding of this technique's limitations and continue its development.

Giant Congenital Melonocytic Nevi of Face-Primary Excision with Reconstruction Using Self-Filling Osmotic Expanders

Congenital hairy nevi or giant congenital melanocytic nevi (GCMN) especially that of the face pose a great challenge to reconstructive surgeons. These unsightly lesions can be psychologically damaging to both parent and child. A variety of treatment options exist for the management of such cases. In this review article, we present two children who had a GCMN of their face managed with self-inflatable tissue expanders (osmotic tissue expanders [OTEs]) for single stage excision, and reconstruction is presented. The uses of self-inflating tissue expanders are now a regular choice for tissue cover in wide areas and in children.