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One-stage breast reconstruction using McGhan Style 150 biodimensional expanders: a review of 107 implants with six years experience.

Permanent expanders have revolutionised breast reconstructive surgery, allowing one-stage procedures and the development of increasingly sophisticated implants (textured, anatomically shaped) has played an important role in enhancing the aesthetic outcomes. It is important to evaluate the tolerability of the implant. The aim of this present study was to evaluate the survival curves for McGhan Style 150 permanent expanders, in a consecutive series of breast reconstructions. Complications rates were also examined. Between April 1997 and May 2003, 107 McGhan Style 150 expanders (either full height or short height depending on patients' requirements) were used in 97 consecutive patients for a variety of breast reconstructive procedures. Overall, 46 devices were used for immediate reconstruction, 15 for delayed reconstruction and 46 for implant exchange, respectively. The mean age at implantation was 48 years (min: 26; max: 71). The mean follow-up was 60 months (min: 12; max: 72). Explantation was considered the most objective outcome variable, therefore this parameter was carefully monitored and then analysed using the Kaplan-Meier method of survival analysis. Different curves were compared using the log-rank test. Long term complications were also recorded. Among complications the most frequent finding was Baker 3-4 capsular contracture, occurring in 26% of immediate reconstructions at six years. Explantations increased in an almost linear fashion, with an overall rate of 25%, with a statistically significant difference among immediate reconstruction group and the implant exchange group. The rate of explantations was high, if compared with other series, because the sample included patients undergoing strong adjuvant therapies, particularly in the immediate group (locally advanced disease). The overall rate of explantations and of capsular contracture was found to be significantly lower in the delayed and substitution groups, than the immediate group (p<0.05). In our hands, the McGhan Style 150 anatomically shaped permanent expanders were associated with acceptable results, especially when used as 'permanent prostheses' for second stage procedures.

Adult↗

Which is the best position for the remote injection dome using the adjustable expander/prosthesis in breast reconstruction? A comparative study.

Breast reconstruction using mammary implants is a routinely performed surgical procedure that gives good aesthetic results with a relatively simple operation for the patients. When an adjustable expander/prosthesis with remote dome is used for reconstruction, the device is filled through an injection dome connected to the implant through a filling tube. The injection dome is usually inserted into a subcutaneous pocket, either in the axillary area or, most frequently, in the lower lateral thoracic area. Sometimes, this location is not well tolerated by the patient because of pain or discomfort in the breast-thoracic area and can give problems related to the distance, which causes kinking of the filling tube. To avoid this inconvenience and because of frequent patient complaints, the authors decided 3 years ago to place the injection dome in a parasternal position and compare this location with the previously used lower lateral thoracic location. Two hundred sixty patients were divided into two groups (130 patients in each group) and evaluated. All patients underwent mammary reconstruction in the authors' department using Becker adjustable implants. In all patients, the injection microdome was used. In group A, the injection microdome was positioned in the lower lateral thoracic area; in group B, the injection microdome was positioned in a parasternal area. Both groups were compared, considering different features such as pain, discomfort, ease of injection, pain during puncture, aesthetic appearance, risk of kinking, and risk of upside-down rotation of the dome. Average follow-up was 1.6 years. Statistical analysis was performed using Pearson's chi-square test regarding the differences in frequency of two features-aesthetic appearance and pain during puncture-between the two groups. The comparisons regarding both aesthetic appearance and pain during puncture did show a significant difference between the two groups, with a value of p < 0.05 in both cases. In the present study, the results showed how the patients had less pain during puncture and a better aesthetic appearance when the microdome was located in the parasternal position instead of the lower lateral thoracic area. Advantages and disadvantages of the locations used are discussed in this article.

Adult↗

Facial reconstruction for radiation-induced skin cancer.

Radiation-induced skin cancers can be difficult to diagnose and treat. Typically, a patient who has received orthovoltage radiotherapy for disorders such as acne, eczema, tinea capitis, skin tuberculosis, and skin cancer can expect that aggressive skin cancers and chronic radiodermatitis may develop subsequently. Cryptic facial cancers can lead to metastases and death. Prophylactic widefield excision of previously irradiated facial skin that has been subject to multiple recurrent skin cancers is suggested as a method of deterring future cutaneous malignancy and metastases. The use of tissue expanders and full-thickness skin grafts offers an expedient and successful method of subsequent reconstruction.

Acne Vulgaris↗

Tissue expansion of the head and neck. Indications, technique, and complications.

Tissue expansion is indicated in the reconstruction of various defects of the head and neck in instances where there is inadequate adjacent tissue to allow either primary closure of the defect or repair with a local flap. It may also be indicated in instances where repair of a defect by an alternative method such as a local, regional, or distant flap will result in an unacceptable donor or recipient site deformity. Although tissue expansion is simplistic in concept, it does require judgment and indepth preoperative planning to ensure optimal results. The complication rate is high for tissue expansion in the head and neck, particularly in the cheek and neck area. Despite the frequency of complications, in the vast majority of cases the intended reconstruction is successful.

Dermatologic Surgical Procedures↗

Rapid intraoperative tissue expansion in reconstruction of the head and neck.

A prolonged tissue expansion has the advantage of creating large amounts of additional skin for reconstructing cutaneous defects that might not be possible without the use of multiple, regional, distant, or microsurgical flaps. In spite of this, there are disadvantages, many of which can be circumvented by the use of rapid intraoperative tissue expansion instead. Although rapid expansion does not increase skin surface area as much as prolonged expansion, it may be helpful in assisting with closure of defects that might otherwise be problematic.

Face↗

Rapid intraoperative tissue expansion for closure of facial defects.

Rapid intraoperative tissue expansion (RITE) has been shown to have definite applicability to reconstruction in the head and neck. However, widespread use of this modality has yet to be adopted by the otolaryngologic community. Believing that RITE might offer some advantages in the reconstruction of soft-tissue facial defects following Mohs micrographic surgery for cutaneous malignant neoplasms, we evaluated 30 consecutive patients referred for cosmetic reconstruction after Mohs micrographic surgery for the use of RITE. Eight patients were selected and underwent reconstruction using a total of 10 tissue expanders. Herein, we describe our experience with this initial series as well as some background and future applications of RITE.

Adult↗

Versatile use of skin expanders in facial plastic surgery.

Large soft-tissue resection defects of the face and scalp present an arduous technical problem for the facial plastic surgeon. Successfully matching tissue coverage with similar skin color and texture is usually limited by the amount of available local skin. Also, the need to limit distortion of fixed anatomic sites when harvesting local skin must be addressed. With the advent and utilization of soft-tissue expanders, the availability of local skin is increased and anatomic distortions are limited. This article describes the versatile use of skin expansion in facial plastic and reconstructive surgery. Expansion techniques include long-term expansion for scalp and cervicofacial defects. Acute intraoperative expansion techniques address repair of perioral, labial, and nasal mucosal lining defects. The success, limitations, and complications of these techniques are reviewed.

Adolescent↗

Long-term nasal mucosal tissue expansion use in repair of large nasoseptal perforations.

Reperforation rates of large, surgically closed nasoseptal perforations remain unacceptably high (30% to 70%). With the advent of newer surgical techniques, including external decortication rhinoplasty and midface degloving, excellent exposure of the intranasal anatomy is afforded. The limiting factor of these approaches is the deficiency of local intranasal mucosal lining, which is used to close large septal perforations. The paucity of nasal mucosal lining results in excessive tension on the perforation closure suture line that leads to distal flap ischemia, anastomosis breakdown and, ultimately, reperforation of the septum. Alternatively, using intraoral mucosal flaps of sufficient length and width to close large perforations results in significant and unacceptable donor-site morbidity. We present our technique of harvesting additional local endonasal mucosa using long-term soft-tissue expanders. Long-term nasal mucosal expansion was used in the closure of large septal perforations in five patients. Complications included one case of expander exposure and the morbidity of prefacial expander injections. Total closure of all five septal perforations was documented at the 1-year postsurgical visit. Histologic and electron-microscopic examinations of the expanded nasal floor mucosa are presented.

Collagen↗

Impact of tissue expansion on flap prefabrication: an experimental study in rabbits.

This study was designed to determine whether tissue expansion after vascular pedicle implantation would increase the survival area of prefabricated skin flaps. In 20 New Zealand white rabbits, the vascular pedicle consisting of the central artery and vein of the left ear was implanted into the neck. At the time of pedicle implantation a subcutaneous pocket was created measuring 5 x 14 cm beneath the implantation site. Tissue expanders of three different sizes and volumes were implanted in the rabbits of three treatment groups. No tissue expander was implanted in the animals of the control group. All flaps were transposed after 3 weeks to the contralateral ear, and flap survival was assessed 1 week later. The increased area of the flap survival was statistically significant in all three treatment groups compared to the nonexpanded flaps (P = 0.003, P = 0.004, P < 0.0001, respectively). In addition there was a statistically significant larger area of survival using a 100-cc expander measuring 5 x 14 cm (the same size as the elevated flap) compared to 40-cc (3 x 5 cm) or to 60-cc (4 x 8 cm) expanders (P < 0.001, P = 0.004, respectively). The one-way analysis of variance and the t-test were used to show statistical differences. We conclude that the time necessary for neovascularisation of the skin flap could be used to expand the tissue, not only increasing the amount of available tissue, but also enhancing the vascularity.

Analysis of Variance↗

Biomaterial properties and biocompatibility in cell culture of a novel self-inflating hydrogel tissue expander.

The aim of this study was to investigate the swelling properties and the biocompatibility of a novel tissue expander material. The self-inflating material is a hydrogel consisting of a modified copolymer of methylmethacrylate and N-vinyl-2-pyrrolidone, which takes up water by osmosis. To increase the swelling volume, the primarily neutral gel material was modified by converting it into an ionized gel. To study the swelling and pressure behavior of the material, the anhydrous gel cylinders were equilibrated in distilled water, saline, and sugar solutions. The biocompatibility was investigated in cell culture. We tested the hydrogel eluate after swelling for cytotoxicity and mutagenicity using the cell lines MRC-5 and P3X63 Ag8 653 (Ag8). Furthermore, particles of the material were added to cell cultures to induce foreign body reactions and to verify its influence on monocyte differentiation. The material has a swelling capacity (Q = maximum swelling volume/anhydrous volume) of 5 to 50 depending on the degree of ionization of the polymer network. In this study, two polymer modifications with a swelling equilibrium of Q = 11.1 and 30 in water were tested. The swelling ratio also depends on concentration and ion content of the equilibration medium. The highest swelling capacity was found in water, the lowest in Ringer's solution. The swelling of the anhydrous material with the swelling capacity of Q = 11.1 fits best the average purpose of material properties for tissue expansion and generates a maximal hydrostatic pressure of approximately 235 mmHg. Effects on cell proliferation were detected only at the highest eluate concentration tested (i.e., eluate: culture medium = 1:1), which was far beyond physiological values, whereas mutagenicity was absent. Monocytes neither migrated nor tightly attached to the hydrogel. They neither phagocytose the material nor did they show any sign of a foreign body reaction, e.g., formation of multinucleated giant cells or monocyte proliferation. In the presence of hydrogel material, the differentiation processes of monocytes to macrophages or dendritic cells, respectively, were found to be undisturbed. From these results, we conclude that there is a high biocompatibility of the expander material, which may be a favorable and interesting candidate for further clinical applications.

Animals↗

Kinetic study of release of silicon compounds from polysiloxane tissue expanders.

The release behavior of typical commercial tissue expanders has been examined by carrying out two kinds of experiments: 1) Determination of chemical nature and its modification after in vivo use by X-ray photoelectron spectroscopy for chemical analysis. This study has been paralleled by scanning electron microscopy with associated energy dispersive X-ray analysis of surface, as well as by silicon compounds analysis of tissues around implants. 2) Kinetic examination of silicon compounds released by the biomaterial in physiologic solution at 36 +/- 0.3 degrees C. Results of these investigations have shown independently that the starting material was not a filler-free, pure polymer, but a composite, reinforced elastomer, with the reinforcing agent most seemingly represented by silicon dioxide. Release of latter, with a relatively fast kinetics, is compatible with data of the simulating laboratory runs in the physiologic solution. All these facts seem to rule out any hypothesis of a prevailing siloxane oligomer migration. The correlation of kinetic and physicochemical tests with the in vivo behavior is discussed.

Chemical Phenomena↗

Ex vivo evaluation of ferromagnetism, heating, and artifacts of breast tissue expanders exposed to a 1.5-T MR system.

Three breast tissue expanders were evaluated for compatibility with MR imaging (1.5 Tesla). The metallic components of the breast tissue expanders were shown to be nonferromagnetic, heating < or = .2 degrees C and the artifacts varied. These results indicate that MR procedures may be performed safely in patients with these implants; however, artifacts may obscure implant leaks or breast lesions if located near and metal portion of the breast tissue expanders.

Artifacts↗

Breast reconstruction with alloplastic implants.

This article reviews immediate and delayed breast reconstruction with prosthetic implants, and the effect of irradiation therapy. Despite widespread use of breast conserving surgery for early breast cancer, many breast cancer patients still undergo mastectomy. Some of these patients choose breast reconstruction. Over the last 30 years, techniques for breast reconstruction have evolved significantly with new alternative techniques and improved surgical devises. Immediate or delayed breast reconstruction with silicone prosthesis can be an excellent option. Implant reconstruction may be single or two stage procedures. Traditionally, small breasts with minimal ptosis are suited for single-stage reconstruction. Large breasts or inadequate skin require expanders followed by implants. Minimal excision mastectomy and biological spacers are allowing larger breast single stage reconstruction and improved aesthetics for two stage procedures. With recent studies suggesting survival advantage of post-mastectomy irradiation, many candidates for breast reconstruction are receiving radiotherapy, which complicates healing after breast reconstruction.

Breast Implants↗

Total scalp replantation based on one artery and one vein.

A successful replantation of a totally avulsed scalp, including both eyebrows, with only one arterial and one venous anastomosis to the superficial temporal vessels is described. Apart from a small partial skin necrosis of the right eyebrow, the entire transplant survived. Subsequently, the patient required only minor additional skin grafting, correction of scars with a skin expander, and reconstruction of the eyebrow with hair micrografts. Replantation of the total scalp based on two or more vessels has previously been recommended and reported elsewhere. In the present case, complete survival of the scalp on only one artery and one vein was demonstrated, indicating that replantation should be considered even if available vessels for anastomosis are minimal.

Adult↗

Elongation of wallerian degenerating nerve with a tissue expander: a functional, morphometrical, and immunohistochemical study.

The purpose of this experimental study was to investigate the usefulness and mechanism of the expansion of wallerian degenerating nerve. The study consisted of two experiments: Experiment I, functional and morphometrical analysis, and Experiment II, immunohistochemical analysis. In Experiment I, the rat nerve crush model was used to assess the effects of mechanical expansion of wallerian degenerating nerves on axonal regeneration. In Experiment II, the rat sciatic nerve cut model was used to investigate the effects of nerve expansion on Schwann cell events in wallerian degenerating nerves. In both experiments, nerve expansion was carried out between days 5 and 9 after nerve injury, using a rubber tissue expander placed beneath the sciatic nerve. In Experiment I, rats were divided into the following three groups according to the volume of saline injected: control group (nerves were crushed, without saline injection); 8-ml injection group; and 11-ml injection group. Functional recovery was assessed using the sciatic functional index until 54 days after nerve injury. Rats in all three groups showed good functional recovery, and the morphometrical analysis revealed no significant differences among the three groups. In Experiment II, anti-S-100 protein polyclonal antibody and anti-proliferating cell nuclear antigen monoclonal antibody were used to identify proliferating Schwann cells. Rats were divided into two groups: control group (nerves were cut, without expansion) and nerve expansion group. In the control group, proliferating Schwann cells were observed only between days 3 and 7. By contrast, these cells continued to be seen in the expanded nerves until day 16. These results suggest that the expansion of wallerian degenerating nerve does not have a deleterious effect on the axon-promoting property of Schwann cell tubes and that the expansion is dependent not only on the viscoelasticity of the nerves but also on enhanced proliferation of Schwann cells.

Animals↗

Maximum intraoperative elongation of the rat sciatic nerve with tissue expander: functional, neurophysiological, and histological assessment.

The purpose of this study was to assess the maximum rapid intraoperative elongation of the rat sciatic nerve with the use of tissue expander, and its possible functional recovery. One hundred and eight rats were divided into five groups, and their right sciatic nerves were expanded with a 10-cc, 12-cc, 14-cc, 16-cc, and 18-cc expander, respectively, for 1 h. The functional recovery of the nerve was assessed at intervals up to 3 months, using the sciatic function index (SFI), neurophysiological indices, and histology. The maximum intraoperative elongation was observed in group IV (16-cc volume of tissue expander), at about 23.83%. SFI decreased between the first and seventh postoperative days, but gradually recovered, reaching preoperative values in all groups according to the formulas of De Medinaceli et al. (Exp. Neurol. 77:634-643, 1982) and Bain et al. (Plast. Reconstr. Surg. 83:129-136, 1989). Latency and motor conduction velocity demonstrated deterioration after expansion, which peaked after surgery. Recovery was gradually completed by the end of the experiment. The histological findings indicated minor aberrations immediately after expansion and maximal demyelination with axonal disruption on day 15. The reparative process started by day 30 and continued until day 90, when almost no histological changes were observed. In conclusion, intraoperative nerve expansion successfully elongates the rat sciatic nerve up to 23.83%. But it causes functional and morphological abnormalities, which are of moderate to severe degree, are of short duration, and are reversible. Intraoperative nerve expansion might be a valuable solution in the treatment of short nerve gaps, but its clinical application still needs to be evaluated.

Animals↗

The creation of a small bowel pouch by tissue expansion--an experimental study in pigs.

Tissue expanders (inflatable silicone balloons) were implanted into a bypassed ileum segment of seven pigs and consecutively filled over 8 to 12 weeks. The mean increase of the volume of the small bowel loops was 12 fold with a maximum of 22.8 times the original volume. The final volume 9 weeks after expander removal still presented an increase of 500%. Histologically there was an increase of the thickness of all layers of the bowel wall, especially in the tunica muscularis. The mucosa showed a value above normal in mean in vitro 14C-resorption capacity per surface area in the reintegrated bowel. Possible clinical applications of the augmentation of the gut by expansion as a rectum substitute after proctocolectomy, as a urinary bladder or stomach substitute, and for the treatment of short bowel syndrome are discussed.

Animals↗