Proliferation rate of human osteoblast-like cells on alloplastic biomaterials and their clinical application for the transnasal duraplasty procedure

The possibility of transmission of slow virus infection (HIV) and Creutzfeld-Jakob disease by cadaveric dura implants makes it necessary to find synthetic, absorbable materials for the reconstruction of the dura mater. Various procedures with autologous or alloplastic material are described. Four commercially available biomaterials were choosen to study the proliferation rate and the biocompatibility of human osteoblast-like cells (HOB-like cells) on 2- dimensional material by biochemical analysis. With a proliferation assay, the viability and the proliferation capacity of osteoblast-like cells were evaluated. A clinical trial was added to study resorbable fleece as one of the previously tested biomaterial in a small patient group (8 patients) to close anterior cranial fossa dura defects. The results of the proliferation assay showed the highest proliferation rate of HOB-like cells on resorbable fleece. All patients in our clinical trial with anterior cranial fossa dura defects were successfully treated with resorbable fleece. There was no evidence for persisting cerebrospinal fluid rhinorrhea or foreign body reaction after the period of wound healing. The present study demonstrated an excellent biocompatibility of resorbable fleece. The vicryl fleece is an alternative alloplastic material for endonasal closure of defined substantial defects of the dura with cerebrospinal fluid.     

Poland's syndrome: correction of thoracic anomaly through minimal incisions

A method that minimizes residual scarring following Poland's syndrome correction by latissimus dorsi muscle transposition and placement of a submuscular breast implant is described. In order to reduce any resulting unsightly scarring and, in particular, eliminate the anterior thoracic scar, both a dorsal S-shape and an axillary incision were made and the muscle flap was raised. A prosthesis was then inserted and the muscle flap sutured to the anterior chest wall through an anterior incision symmetrical to the inferior border of the contralateral areola. The latter is a previously undescribed approach that produces good cosmetic results.     

The extended vertical rectus abdominis myocutaneous flap for breast reconstruction

The extended vertical rectus abdominis myocutaneous flap has been used in 34 patients for breast reconstruction after radical mastectomy. This flap can reconstruct a large ptotic breast mound and fill the infraclavicular and axillary areas. The operative technique and a discussion of the method are presented. There are several advantages to the extended vertical rectus abdominis myocutaneous flap. First, the main advantage of this flap is its reliable vascular supply, which can reach to the infraclavicular and axillary areas. Second, the large volume of this flap can reconstruct the large ptotic breast, fill the infraclavicular hollow, and create an axillary fold. Third, no lower abdominal wall hernias have developed, and use of alloplastic abdominal wall reinforcement is not necessary. Finally, the simultaneous beneficial effect of horizontal abdominoplasty, which further enhances the patient's body image by narrowing the waist, is unique to this vertical abdominal flap. The disadvantages of this flap include (1) the midline abdominal scar, (2) an umbilical scar on the reconstructed breast, and (3) in principle, inappropriateness for the patient who desires pregnancy postoperatively.     

Hypertrophic scarring and keloids: pathomechanisms and current and emerging treatment strategies

Excessive scars form as a result of aberrations of physiologic wound healing and may arise following any insult to the deep dermis. By causing pain, pruritus and contractures, excessive scarring significantly affects the patient's quality of life, both physically and psychologically. Multiple studies on hypertrophic scar and keloid formation have been conducted for decades and have led to a plethora of therapeutic strategies to prevent or attenuate excessive scar formation. However, most therapeutic approaches remain clinically unsatisfactory, most likely owing to poor understanding of the complex mechanisms underlying the processes of scarring and wound contraction. In this review we summarize the current understanding of the pathophysiology underlying keloid and hypertrophic scar formation and discuss established treatments and novel therapeutic strategies.     

Blindness as a complication of subcutaneous nasal steroid injection

Blindness as a result of steroid injection into areas adjacent to the eyes, namely the interior of the nose and eyelids, has been described in the otolaryngologic and ophthalmologic literature but at no time in the plastic surgery literature. We describe a case of permanent visual loss at the time of injection of a long-acting steroid to the dorsum of the nose for postrhinoplasty scarring. We suggest that before steroid injection for elective procedures, the patient be informed of all possible consequences of complications even if their occurrence is very rare.     

Selenium determination in biological fluids using Zeeman background correction electrothermal atomic absorption spectrometry

Procedures for the direct determination of total selenium in urine, serum, and blood using electrothermal atomic absorption spectrometry are presented. In the selected experimental conditions, Zeeman correction is mandatory to compensate for the high background signals. The sample diluted and containing 0.1% (w/v) Triton X-100 is introduced directly into the electrothermal atomizer. A solution containing 15% (w/v) hydrogen peroxide, 0.65% (w/v) nitric acid, and 0.5% (w/v) nickel is injected separately into the atomizer. Calibration is carried out using the standard additions method. The detection limit is 30 pg selenium. If palladium, instead of nickel, is used as the chemical modifier, calibration can be carried out against aqueous standards, and the detection limit is 45 pg. In this case, three separate injections are required to prevent precipitation problems in the automatic injector. The reliability of the procedures is checked by analyzing three certified reference materials and by recovery studies. Mean recoveries are 99.7% for serum, 99.4% for urine, and 100.8% for blood samples. Relative standard deviation values are +/-4.0% for serum, +/-3.9% for urine, and +/-4.5% for blood.     

Procedure for laryngotracheal separation in the goat: development of a new animal model for analysis of craniofacial growth

Most animal models used to study the process of postnatal craniofacial growth require direct manipulation of the craniofacial area, a growth period, then evaluation of the area. However, the scar tissue associated with direct manipulation of the craniofacial structures can produce growth abnormalities that are unrelated to the manipulation itself. To avoid this confounding variable in the study of craniofacial growth, we developed an animal model that involves laryngotracheal separation in a young animal. Our procedure completely separates the trachea from the upper aerodigestive tract and removes the site of scar tissue formation from the region of investigation. The tracheal stomas of the goats we describe were maintained for as long as 9 months. Unlike human patients, goats with laryngotracheal separation require laryngectomy tubes to prevent life-threatening stenosis of the tracheal stoma. Here we describe the operative procedure and post-operative care required for this new animal model.     

Endoscopic correction of pectus excavatum

Endoscopic surgery is minimally invasive and can be used to achieve superior cosmetic results. Conventional correction of pectus excavatum results in a long scar. Correction by use of endoscopic surgery involves a smaller skin incision. In this study, endoscopic correction of pectus excavatum was performed in 20 cases. A small transverse skin incision was made above the xyphoid process. A wide area beneath the pectoralis major muscle was dissected under endoscopic visualization. Subperichondrial resection was performed under direct visualization when possible. Subperichondrial resection of the third or fourth rib was performed under endoscopic visualization. Ravitch's chondrotomy of the second or third rib was performed under endoscopic visualization. Endoscopy was also useful for sternal elevation, with minimal risk of pleural perforation. Kirschner wire was inserted percutaneously under the sternum to prevent postoperative paradoxical respiration. In all cases, the postoperative course was uneventful. The advantages of endoscopic pectus excavatum correction are a short scar, control of bleeding, safe dissection of the pleura from the sternum without the risk of pleural perforation, and ease of sternal elevation without injury to the intramammary vessels. However, the endoscopic operation is long and is not useful in adults because subperichondrial resection in adults is difficult to perform.     

Free-fat injections for the correction of hemifacial atrophy

Three adult patients with long-standing hemifacial atrophy were treated with repeated free-fat injections at 4- to 8-week intervals. The longest follow-up study to date is 18 months, and following the expected postoperative resorption, no further loss of bulk of injected fat has been observed. On palpation, the feel of the fat is normal, and facial expression is also good. The relative ease of this procedure, which does not entail any scarring, appears to justify more widespread use of free-fat injections to restore facial soft-tissue depressions.     

CD44-dependent inflammation,fibrogenesis, and collagenolysis regulates extracellular matrix remodeling and tensile strength during cutaneous wound healing

Cutaneous wound healing consists of three main phases: inflammation, re-epithelialization, and tissue remodeling. During normal wound healing, these processes are tightly regulated to allow restoration of skin function and biomechanics. In many instances, healing leads to an excess accumulation of fibrillar collagen (the principal protein found in the extracellular matrix - ECM), and the formation of scar tissue, which has compromised biomechanics, tested using ramp to failure tests, compared to normal skin (Corr and Hart, 2013 [1]). Alterations in collagen accumulation and architecture have been attributed to the reduced tensile strength found in scar tissue (Brenda et al., 1999; Eleswarapu et al., 2011). Defining mechanisms that govern cellular functionality and ECM remodeling are vital to understanding normal versus pathological healing and developing approaches to prevent scarring. CD44 is a cell surface adhesion receptor expressed on nearly all cell types present in dermis. Although CD44 has been implicated in an array of inflammatory and fibrotic processes such as leukocyte recruitment, T-cell extravasation, and hyaluronic acid (the principal glycosaminoglycan found in the ECM) metabolism, the role of CD44 in cutaneous wound healing and scarring remains unknown. We demonstrate that in an excisional biopsy punch wound healing model, CD44-null mice have increased inflammatory and reduced fibrogenic responses during early phases of wound healing. At wound closure, CD44-null mice exhibit reduced collagen degradation leading to increased accumulation of fibrillar collagen, which persists after wound closure leading to reduced tensile strength resulting in a more severe scarring phenotype compared to WT mice. These data indicate that CD44 plays a previously unknown role in fibrillar collagen accumulation and wound healing during the injury response.     

Scarless fetal wound healing: a basic science review

SUMMARY: Scar formation is a major medical problem that can have devastating consequences for patients. The adverse physiological and psychological effects of scars are broad, and there are currently no reliable treatments to prevent scarring. In contrast to adult wounds, early gestation fetal skin wounds repair rapidly and in the absence of scar formation. Despite extensive investigation, the exact mechanisms of scarless fetal wound healing remain largely unknown. For some time, it has been known that significant differences exist among the extracellular matrix, inflammatory response, cellular mediators, and gene expression profiles of fetal and postnatal wounds. These differences may have important implications in scarless wound repair.     

MicroRNA 181b Regulates Decorin Production by Dermal Fibroblasts and May Be a Potential Therapy for Hypertrophic Scar

Hypertrophic scarring is a frequent fibroproliferative complication following deep dermal burns leading to impaired function and lifelong disfigurement. Decorin reduces fibrosis and induces regeneration in many tissues, and is significantly downregulated in hypertrophic scar and normal deep dermal fibroblasts. It was hypothesized that microRNAs in these fibroblasts downregulate decorin and blocking them would increase decorin and may prevent hypertrophic scarring. Lower decorin levels were found in hypertrophic scar as compared to normal skin, and in deep as compared to superficial dermis. A decorin 3’ un-translated region reporter assay demonstrated microRNA decreased decorin in deep dermal fibroblasts, and microRNA screening predicted miR- 24, 181b, 421, 526b, or 543 as candidates. After finding increased levels of mir-181b in deep dermal fibroblasts, it was demonstrated that TGF-β₁ stimulation decreased miR-24 but increased miR-181b and that hypertrophic scar and deep dermis contained increased levels of miR-181b. By blocking miR-181b with an antagomiR, it was possible to increase decorin protein expression in dermal fibroblasts. This suggests miR-181b is involved in the differential expression of decorin in skin and wound healing. Furthermore, blocking miR-181b reversed TGF-β₁ induced decorin downregulation and myofibroblast differentiation in hypertrophic scar fibroblasts, suggesting a potential therapy for hypertrophic scar.     

Treatment of extensive sternum keloid scar with surgical removal and immediate reconstruction with skin flaps from a combined mammaplasty

We report the case of a 47-year-old woman with a large keloid scar on the sternum who was submitted to a simultaneous scar removal with bilateral breast-reduction mammaplasty. Breast reduction was performed to reduce local skin tension and to provide a skin flap for the full reconstruction of the scar-removal site. The association of these surgical procedures stands as a viable alternative for the reconstruction of the sternum region, producing less keloid scarring.     

Reducing complications in cervicofacial rhytidectomy by tumescent infiltration: a comparative trial evaluating 678 consecutive face lifts

Tumescent infiltration has been widely used in body-contouring surgery to facilitate dissection and reduce blood loss. Although its use in facial surgery has been suggested, there are presently no comparative studies of its efficacy. The aim of this study was to investigate the long-term outcome in a large series of consecutive face lifts performed with and without tumescence. During a 6-year period, 678 consecutive face lifts were performed: 449 without tumescence and 229 with tumescent infiltration using 200 ml on each side of the face. The spectrum of techniques included the extended superficial musculoaponeurotic system (SMAS) procedure, the lateral SMASectomy, the extended supraplatysmal plane lift, and the cutaneous face lift. Complications, such as hematoma, skin necrosis, alopecia, and scar quality, were compared between groups using Fisher's exact test. The use of tumescent infiltration facilitated dissection, particularly in the neck. Postoperative swelling and bruising were reduced in the tumescent group. In comparisons of major complications between groups, no difference was seen in hematoma rate (p > 0.5), although the incidence of other complications was significantly reduced by tumescent infiltration. Significant reduction was observed in the rate of skin necrosis (p = 0.03), alopecia (p = 0.006), hypertrophic scarring (p = 0.001), stretched scarring (p = 0.003), and scar revision (p < 0.001). This is the first comparative study of tumescent infiltration in facial rejuvenation surgery. Tumescence made dissection easier and significantly reduced the incidence of troublesome complications. The surgical technique and aesthetic implications for rejuvenation surgery are discussed.     

Transconjunctival lateral canthopexy in Down's syndrome patients: a nonstigmatizing approach

In Down's syndrome patients, surgical correction of the palpebral fissure obliquity through an external approach may produce a red, slightly hypertrophic scar. A transconjunctival approach for this repair was used for 15 Down's syndrome patients aged 3 to 17 years (mean 8.7 years), and the results were compared with those in two boys aged 6 and 17 years who underwent correction by the external approach. Palpebral fissure inclinations were recorded using anthropometric measurements preoperatively and 6 months postoperatively. Inclinations were reduced significantly by either technique; however, often the precise degree of the improvement was clear only from the measurements rather than from photographs. Complications of the transconjunctival approach were few, and there were no problems with wound healing and no ocular injury. Transconjunctival lateral canthopexy is a safe, effective method that avoids a potentially stigmatizing external scar.     

Periareolar approach for the correction of congenital symmastia

This report elucidates the continued and relatively rare problem of congenital symmastia and its surgical repair without concomitant bilateral breast reduction. This case highlights the use of suction-assisted lipectomy techniques to address the excess fat in the presternal web and a periareolar approach for access to the intermammary space. The periareolar incision allows for the use of a concealed approach and the avoidance of a central scar that could result in hypertrophy or keloid formation, especially in this patient who is more prone to hypertrophic scarring. Furthermore, plication of the central web dermis to the sternal periosteum in a more superior position serves to not only correct the symmastia but also redrape the excess skin and restore the blunted inframammary folds.     

Effect of Mederma on hypertrophic scarring in the rabbit ear model

Currently accepted conservative treatments of hypertrophic scars are limited to steroid injections, radiation therapy, and silicone occlusive therapy. However, the use of Mederma for these problematic lesions has become quite prevalent in the clinical setting. Little scientific evidence exists to support the efficacy of this product in reducing hypertrophic scars. The aim of this study was to study the effects of Mederma on hypertrophic scars in the rabbit hypertrophic scar model, allowing the histologic quantification of scar elevation, dermal collagen organization, vascularity, and inflammation and the gross examination of scar erythema. Full-thickness wounds down to cartilage, four per ear, were created in four New Zealand White rabbits, for a total of 32 scars. Twenty-eight days after the initial wounding, the hypertrophic scars were photographed, and treatment of half of the scars on each ear was begun with Mederma three times per day for a total of 4 weeks. The untreated scars served as control scars and were left exposed to air. After 4 weeks of treatment, the scars were once again photographed. The rabbits were then killed, and the scars were analyzed histologically. The pretreatment and posttreatment photographs were compared by using computer quantification of magenta, yellow, and cyan expression within the scars.Histologic analysis demonstrated no significant reduction in scar hypertrophy or scar elevation index. However, a significant improvement in dermal collagen organization was noted on comparing Mederma-treated scars with untreated control scars (p < 0.05). No significant difference in dermal vascularity or inflammation was noted. Computer analysis of the scar photographs demonstrated no significant reduction in scar erythema with Mederma treatment. The active product in Mederma, allium cepa, has as its derivative quercetin, a bioflavonoid noted for its antiproliferative effects on both normal and malignant cells, and its antihistamine release effects. These properties could theoretically prove beneficial in reversing the inflammatory and proliferative responses noted in hypertrophic scars. Despite the authors' inability to demonstrate a reduction in scar hypertrophy, the improvement in collagen organization noted in the Mederma-treated scars suggests it may have an effect on the pathophysiology of hypertrophic scar formation.