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Reconstruction of postburn scar contracture of the neck by expanded skin flaps.

Flexion contracture of the neck after burns can produce severe functional deformity. Excision and split or full thickness skin grafts, local or distant flaps, and free flaps have been used for reconstruction. Recently, tissue expansion has been introduced as an additional reconstructive procedure. We have used tissue expansion for reconstruction of postburn neck contractures. Twelve patients with ages that ranged from 9 to 34 years were treated with expanded fasciocutaneous supraclavicular and shoulder flaps. No flap necrosis has been seen. In two patients, reconstracture occurred between the expanded flap and uninvolved skin. To date we have not seen any problems with nerve neuropraxia and impression on blood vessels.

Adolescent↗

Creep vs. stretch: a review of the viscoelastic properties of skin.

Possessing viscous and elastic rheological properties, skin is viscoelastic. Mechanical creep, defined as the elongation of skin with a constant load over time beyond intrinsic extensibility, has been described as the vehicle harnessed for wound closure with presuturing, intraoperative tissue expansion, skin-stretching devices, and skin retraction with undermining. Resulting from the generation of new tissue due to a chronic stretching force, biological creep plays a role in conventional tissue expansion.

Biomechanical Phenomena↗

Temporary abdominal closure followed by definitive abdominal wall reconstruction of the open abdomen.

BACKGROUND: Inability to close the abdominal wall after laparotomy for trauma may occur as a result of visceral edema, retroperitoneal hematoma, use of packing, and traumatic loss of tissue. Often life-saving, decompressive laparotomy and temporary abdominal closure require later restoration of anatomic continuity of the abdominal wall. METHODS: The trauma registry, open abdomen database, and patient medical records at a level 1 university-based trauma center were reviewed from January 1988 to December 2001. RESULTS: During the study period, more than 15,000 trauma patients were admitted, with 88 patients (0.6%) requiring temporary abdominal closure (TAC). Patients ages ranged from 12 to 75 years with a mean injury severity score (ISS) of 28 (range 5 to 54). Forty-five patients (51%) suffered penetrating injuries, and 43 (49%) were victims of blunt trauma. Indications for TAC included visceral edema in 61 patients (70%), abdominal compartment syndrome in 10 patients (11%), traumatic tissue loss in 9 patients (10%), and wound sepsis and fascial necrosis in 8 patients (9%). Fifty-six patients (64%) underwent TAC at admission laparotomy, whereas 32 patients (36%) required TAC at reexploration. Seventy-one patients (81%) survived and 17 (19%) died. Of the survivors, 24 patients (34%) underwent same-admission direct fascial closure, and 47 patients (66%) required visceral skin grafting and readmission closure. Reconstructive procedures in the patients requiring skin graft excision included direct fascial repair (20 patients, 44%), components separation closure with or without subfascial tissue expansion (18 patients, 40%), pedicled or free-tissue flaps (4 patients, 8%), and mesh repair (4 patients, 8%). One patient refused closure. The mean follow-up was 48 months (range 6 to 144), with an overall recurrence rate of 15% (range 10% to 50%), highest in the mesh repair group. CONCLUSIONS: Silicone sheeting TAC provides a safe and reliable temporary abdominal closure allowing for later definitive reconstruction. Direct fascial repair or components separation closure with or without tissue expansion can be utilized in the majority of patients for definitive reconstruction with low recurrence rate.

Abdominal Injuries↗

Monitoring the formation of thermal lesions with heat-induced echo-strain imaging: a feasibility study.

We investigated the feasibility of using echo-strain images to visualize the extent of high-intensity ultrasound (US)-induced thermal lesions during their formation. Echo-strain, defined as the relative deformation of the backscattered ultrasonic signal, is due to tissue expansion and to changes in the speed of sound during heating. First, a theoretical framework was developed to predict the influence of these effects on the echo signal. Then, a simulation tool was developed to create simulated echo-strain images in thermal lesions. Finally, experimental echo-strain images were acquired in 10 porcine liver samples in vitro for various exposure durations and ultrasonic intensities (resulting in lesions that extended 3 to 8 mm deep from the surface). For this purpose, radiofrequency (RF) frames were acquired at 8 frames per s while heating. For each consecutive pair of RF frames, an echo-strain image was calculated using standard elastographic processing. The echo-strain images were cumulated and displayed. The experimental echo-strain images were compared with gross pathology. The (isoechoic) lesions were visible both in simulated and in experimental cumulated echo-strain images as apparent expansion areas (tensile echo-strain), whereas surrounding tissues exhibited apparent compression. The tensile echo-strain area underestimated the lesion in simulations, but was representative of the lesion in experiments. High correspondence was found between the lesion depth measured from experimental cumulative echo-strain images (y) and from gross pathology (x) (Pearson's correlation = 0.90, linear regression y = x-0.1 mm, residual error = 0 +/- 0.9 mm). We hypothesized that significant tissue expansion made the thermal lesions highly visible in the experimental echo-strain images. In two cases, the ultrasonic intensity was too low to induce a lesion, and the corresponding experimental echo-strain images showed no visible lesion. We conclude that cumulative echo-strain images have the potential to monitor the formation of high-intensity US-induced thermal lesions.

Algorithms↗

Tissue-expanded radial forearm free flap in neck burn contracture.

Neck contracture after burn injury can result in severe functional as well as aesthetic deformities. Contracture can recur even after wide and complete release and full-thickness skin grafting. Recurrence is partly due to the inherent difficulties in both early postoperative immobilization and the required long-term splinting. When adjacent tissues are also burned, adequate local tissue for reconstruction may not be available; therefore, free-tissue transfer may be necessary. The large surface area that is required after adequate release may be provided by tissue expansion before free-tissue transfer. In the case presented the use of tissue-expanded radial forearm free flap for the reconstruction of a recurrent neck contracture is described.

Adult↗

[Progress in the use of tissue expanders for defect closure of the body surface--clinical aspects].

The time-honored principle of tissue expansion has only gained clinical relevance in the past 10 years. Its advantages are that sound tissue of equal texture, color, and quality adjacent to a defect or scarred area can be transposed to treat defects without producing further scars. Especially in the hair covered part of the head, but also in reconstruction of the female breast after mastectomy, in large scars from burns, or in large pigmented nevi, tissue expansion has to be reliable. Only when used in extremities does a higher rate of complication demand a certain restriction.

Adolescent↗

Radiotherapy: effects on expanded skin.

Although the combination of radiation and tissue expansion has been associated with a significant rate of complications, the specific pathophysiology has yet to be clearly elucidated. The objective of this study was to develop a model to identify and examine specific histologic changes associated with tissue expansion and irradiation. Rectangular 50-cc silicone tissue expanders were placed subcutaneously over the midline dorsum of 18 adult New Zealand white rabbits. Preoperative radiographic dosimetry demonstrated that the radiation portal was away from vital intraabdominal structures. The expanders were inflated with 10 cc of saline every other day for a total of 80 cc. Expanders were left in place for 2 to 3 weeks to allow fibrovascular capsule formation. The rabbits were then divided into three groups (six rabbits per group), each receiving one of three nonfractionated doses of radiation (20, 25, or 35 Gy). Half of the expanded skin was irradiated using a single dose, and the other half served as a nonirradiated control. Capsules and skin were harvested 6 weeks after the delivery of radiation, allowing the beginning of chronic radiation changes to occur. Using hematoxylin and eosin staining, histomorphometric analysis was performed. The data were analyzed using Student's test. Although irradiation did not affect dermal thickness, it did cause a statistically significant increase in epidermal thickness. At 20, 25, and 35 Gy the increase in epidermal thickness was 43, 90, and 130 percent, respectively. Although significant epidermal changes could be identified, capsular and dermal alterations were not evident. Further studies evaluating the long-term effects of alterations in capsular formation caused by radiation may be required.

Animals↗

Reconstruction by expansion in the patient with cancer of the head and neck.

Soft-tissue expansion has undergone wide application in reconstructive surgery. The technique has been used about the head and neck, for breast reconstruction, and for reconstruction in the extremities. Scalp reconstruction, total nasal reconstruction, and the movement of flaps of bearded skin using soft-tissue expansion offer selected patients improved results as compared with what could be achieved by using other methods.

Female↗

Increased hair growth and density following controlled expansion of guinea pig skin and soft tissue.

The goal of this study was to investigate the effect of controlled tissue expansion on hair growth and density using the guinea pig model. Thirty white guinea pigs were randomly divided into three groups: a group to undergo expansion (EXP), an operated control group (OC), and a nonoperated control group (NOC). All groups were shaved to create a 1 cm X 2 cm tuft of dorsal hair, which was subsequently dyed. Only the EXP and OC group members underwent construction of a pocket beneath the tuft. Only the EXP group was implanted and expanded over four weeks. The EXP group revealed a significant increase (p less than 0.005) over the controls in both the number of new white hairs produced (W) and density proportion (W/A). The OC group exhibited a significant increase (p less than 0.005) over the NOC group in both W and W/A. Mechanisms to explain the results are postulated. These include the possible roles of increased follicular mitotic activity (hair follicle transformation and cycle dynamics) and improved perifollicular vascularity (capsule formation and the delay phenomenon of skin pocket construction). Clinical implications are discussed.

Animals↗

[Scalp surgery in children: principles and therapeutic aspects].

Surgical treatment of the lesions of the scalp in children has specific objectives: excision of an extensive lesion using minimum operative procedures, hiding scar in the hair, correcting a wide and ungraceful scar. We reviewed our experience of 450 cases (1990-2000), and found that most common lesions in childhood were: sebaceous hamartoma, pigmentary naevus, post traumatic alopecia, aplasia cutis congenita and complicated hemangiomas. Different surgical procedures are discussed: excision, tissue expansion, hair grafts. Large excision can be performed before three months of life because of the good laxity of the scalp. Tissue expansion is particularly suited to the scalp. Aplasia cutis congenita is a special condition, with local vascular abnormalities: local flaps are prohibited. Hemangiomas may require early surgical treatment in the event of complications.

Adolescent↗

A new technique of scarless expanded forehead flap for reconstructive surgery.

The forehead flap is an ideal flap for reconstructive surgery, especially for that involving reconstruction of the face and neck. However, it is usually limited to use in nasal reconstruction, even when performed in conjunction with tissue expansion, because of the severe visible morbidity of the donor site. In this article, the author discusses his development of a new technique of forehead flap, performed in conjunction with tissue expansion, for reconstructive surgery without visible scarring at the donor site. The technique involved positioning a tissue expander in the forehead pocket under the occipitofrontal muscle and serially inflating the expander over a period of approximately 4 to 6 weeks. Thereafter, an expanded forehead flap was created from the frontal hairline area on the basis of the location of the superficial temporal vessels and transferred into 16 recipient sites in 13 patients as an island flap (n = 8), a free flap (n = 1), or a local random flap (n = 7). The donor site was closed directly into the frontal hairline, without any visible scar. With the author's experience in the use of the island flap for nasal, facial, and neck reconstruction and of the free flap for reconstruction in the extremities, the flap could be as large as 8 x 18 cm without inducing flap necrosis or problems with donor-site closure. All patients (n = 13) had acceptable donor-site aesthetic results, without visible scarring. The results indicate that the flap could be a safe, ample, and color-matched flap for reconstruction of the face and neck and could also diminish donor-site morbidity to a minimum, without an unsightly visible scar. Furthermore, the flap could be formed into a customized free flap, with the above-mentioned advantages, to be transferred to any part of the body.

Adolescent↗

Long-term follow-up of a modified Anton-Hartrampf nipple reconstruction.

This study was performed to determine the degree of shrinkage over time in nipple projection after reconstruction. Nipple-areolar reconstruction was performed using the modified Anton-Hartrampf technique, and pigmentation was achieved with tattooing. This study looked at 28 consecutive patients with nipple reconstruction performed at The Milton S. Hershey Medical Center of the Penn State Geisinger Health Systems between September 1989 and November 1993. Two patients were lost to follow-up and 3 patients died of breast cancer. Thus, 23 patients and a total of 32 nipples were investigated. Initial measurements of nipple projection were taken 2 weeks postoperatively. Patients were followed an average of 38.7 months (range, 11-66 months). Ten patients (18 nipples) had tissue expansion and implantation for breast mound reconstruction. Thirteen patients (14 nipples) had autologous breast mound reconstruction. The mean decrease in projection of the tissue expansion and implantation group was 76.7+/-9.7%. The mean decrease in projection of the autologous reconstruction group was 64.3+/-12.1%. The mean decrease in projection for the entire group was 71.3+/-21.9%. Comparison between the two groups using a two-sample t-test showed p = 0.0047. The authors concluded that there is a significant reduction in nipple projection over time using the modified Anton-Hartrampf technique regardless of the type of breast mound reconstruction. In addition, their results also indicated that nipple projection on the breast mound reconstructed with an autologous musculocutaneous flap technique achieved a better long-term outcome. This study is potentially helpful in planning the initial size of the reconstructed nipple papule to match the opposite normal nipple. Additional studies need to be performed on other types of nipple-areolar reconstruction.

Breast Implants↗

Aplasia cutis congenita. Case report.

The authors report the use of intraoperative tissue expansion in the treatment of a neonate with aplasia cutis congenita, a congenital defect of the scalp and skull. The case for immediate surgical intervention is presented, and intraoperative tissue expansion and cranioplasty are recommended as components of an effective surgical approach.

Adult↗

[Expanded pedicled forearm flap for reconstruction of multiple finger amputations].

Soft-tissue injuries of the hand frequently require flap coverage to preserve structures damaged at the time of injury or to facilitate later reconstruction. The radial forearm flap makes local tissue readily available and offers a simple method of reconstruction. Secondary augmentation of the skin flap by means of tissue expansion appears to be a useful alternative to improve the possibilities of reconstruction. This case report describes a primary reconstruction of a hand with multiple finger amputations using both techniques: Forearm flap and tissue expansion.

Adult↗

Versatility of expanded forehead flaps for facial reconstruction. Case report.

Forehead flaps, sometimes with tissue expansion, are usually used for nasal reconstruction because of the severe aesthetic morbidity of the donor area. In this paper we describe six patients who had facial soft-tissue defects that were repaired by versatile design of the expanded forehead flaps and minimal donor morbidity. The results indicate that forehead tissue expansion can provide ample, thin, well-vascularised, and colour-matched flaps for facial reconstruction. Versatile design of the expanded forehead flap can reduce the donor morbidity to a minimum without a visible unsightly scar.

Adolescent↗

A self-inflating tissue expander.

Tissue expansion is a means of mechanically creating an excess of soft tissue, contiguous to a defect, for use in reconstruction. To accomplish this, a self-inflating implant has been designed, tested, and used clinically. It offers potential advantages over similar percutaneously inflated devices, but has also presented new problems. Histologically, tissue expansion in the guinea pig is relatively innocuous, utilizing this implant; clinical results were similarly encouraging. Further clinical studies and applications await the identification of a more permeable membrane.

Adolescent↗

Full-load expansion technique and preliminary clinical application.

For accelerating the inflation process of soft-tissue expansion, a continuous inflation protocol regarding pain as the criterion of overinflation, the full-load expansion technique, has been introduced. It is carried out by restricting persistently the pressure in the expander near the pain threshold in a state of dynamic equilibrium between the infusing rate and the skin expansion velocity with a simple and practical device. This inflation is neither at a uniform infusion rate nor at a constant filling pressure. Nineteen expanders in 13 patients were inflated following this protocol. Their inflations were fulfilled in 5 to 20 days, depending individually on their anatomic regions, total volumes of infusion, areas of the overlying skin, and patient susceptibilities.

Adult↗