Keloids and hypertrophic scars

Age-dependent biomechanical properties of the skin

The skin fulfills one of its most important functions, that is protection from mechanical injuries, due to the mechanism of reversible deformation of the structure. Human skin is a complex living material but in biomechanical tests it reveals its homogeneous nature. Biomechanical skin parameters change with time. Results of thickness measurements, where the skin was subjected to pressure, revealed that the Young's modulus increased linearly with age. The process of ageing is the reason why the skin becomes thinner, stiffer, less tense and less flexible. Skin tension measured during in vivo uniaxial load and the elasticity modulus are higher in children than in elderly adults. Furthermore, mean ultimate skin deformation before bursting is 75% for newborns and 60% for the elderly. Several types of the main lines were distinguished on the skin. The static lines, described by Langer, correspond to the lines of maximum tension, the Kraissl's lines correspond to the movements of the skin during muscle work, whereas the Borges lines are the relaxed skin tension lines. Biomechanical tests of the human skin help to quantify the effectiveness of dermatological products, detect skin diseases, schedule and plan surgical and dermatological interventions and treatments.

Treatment of refractory keloids with pulsed dye laser alone and with rotational pulsed dye laser and intralesional corticosteroids: A retrospective case series

BACKGROUND AND AIMS

The limited available effective treatments make the management of keloids challenging. Intralesional triamcinolone and pulsed dye laser have been used for the treatment of keloids. We sought to assess the efficacy of a treatment regime using rotational intralesional triamcinolone and pulsed dye laser in the management of keloids. Materials (Subjects) and Methods: Case notes and photographic records of 99 patients with keloids treated with pulsed dye laser (PDL) alone or rotational PDL and intralesional triamcinolone (ILT) at our centre between 2005 and 2010 were reviewed. Patients with raised, erythematous and/or symptomatic keloids unresponsive to ILT alone (usually 6 treatments) are referred for consideration of PDL. Patients are offered repeated rotational treatments of three PDL (4-15 J/cm(2), 7 mm spot, 1.5 msec pulse duration, 595 nm wavelength, DCD, 30 msec spray: 20 msec delay; spaced at 6-8 weeks intervals) followed by one ILT (10 mg or 40 mg/dl). ILT-treated flat but erythematous and/or symptomatic keloids are treated with PDL alone at 6-8 week intervals. Response after each laser treatment is documented as a percentage improvement from baseline. Based on the improvement in redness, thickness and pruritus the operator classified the response to treatment as mild (0-49%), moderate (50-75%) or excellent (>75%). Patients are reviewed at 6 months following last treatment. A patient satisfaction questionnaire was also sent out to all patients who received treatments between 2005 and 2010 and this was compared with the information gathered from the notes.

RESULTS

Of the 99 patients, 58 were women and 41 were men and most were Caucasian (n=84). A total of 755 keloids were treated. The average number of PDL treatments to achieve a moderate-excellent result was 14 in male and 12 in females. Moderate-excellent improvement was seen in 76% patients. The average number of ILT required to achieve a moderate-excellent result was 5 in males and 4 in females. All patients were sent a satisfaction questionnaire and 33 responses were received wherein patients reported an average of 70% improvement in the redness and thickness of the keloids. Localised cutaneous atrophy, self-limiting erythema and injection site discomfort were noted in 3 female patients whilst no side-effects noted in the male cohort.

CONCLUSIONS

Pulsed dye laser with or without intralesional triamcinolone is a moderately effective treatment of keloid scars with a very good side-effect profile and high patient satisfaction.

The severity of Osteogenesis imperfecta and type I collagen pattern in human skin as determined by nonlinear microscopy: proof of principle of a diagnostic method

BACKGROUND

The confirmatory diagnosis of Osteogenesis Imperfecta (OI) requires invasive, commonly bone biopsy, time consuming and destructive methods. This paper proposes an alternative method using a combination of two-photon excitation fluorescence (TPEF) and second-harmonic generation (SHG) microscopies from easily obtained human skin biopsies. We show that this method can distinguish subtypes of human OI.

METHODOLOGY/PRINCIPAL FINDINGS

Different aspects of collagen microstructure of skin fresh biopsies and standard H&E-stained sections of normal and OI patients (mild and severe forms) were distinguished by TPEF and SHG images. Moreover, important differences between subtypes of OI were identified using different methods of quantification such as collagen density, ratio between collagen and elastic tissue, and gray-level co-occurrence matrix (GLCM) image-pattern analysis. Collagen density was lower in OI dermis, while the SHG/autofluorescence index of the dermis was significantly higher in OI as compared to that of the normal skin. We also showed that the energy value of GLCM texture analysis is useful to discriminate mild from severe OI and from normal skin.

CONCLUSIONS/SIGNIFICANCE

This work demonstrated that nonlinear microscopy techniques in combination with image-analysis approaches represent a powerful tool to investigate the collagen organization in skin dermis in patients with OI and has the potential to distinguish the different types of OI. The procedure outlined in this paper requires a skin biopsy, which is almost painless as compared to the bone biopsy commonly used in conventional methods. The data presented here complement existing clinical diagnostic techniques and can be used as a diagnostic procedure to confirm the disease, evaluate its severity and treatment efficacy.

Intralesional cryosurgery and intralesional steroid injection: a good combination therapy for treatment of keloids and hypertrophic scars

Hypertrophic scars and keloids exhibit high recurrence rates following surgical excision. Intralesional cryosurgery (ILC) can achieve a higher degree of effectiveness than the surface cryotherapy. The aim of this study is to assess the clinical efficacy of ILC using Weshahy cryoneedles followed by IL steroid in a trial of getting rid of the fibrous mass by destruction, not by surgery to avoid being under tension of the new scar. This study included 22 patients. Evaluation of the volume reduction of the lesions was done after a single ILC session followed by IL steroid injections. There was a significant decrease in the volume of the lesions after 4 months (P < 0.01), with a volume reduction of 93.5%. By using ILC at the base of keloids or hypertrophic scars, we can change the old fibrous tissue into a recent scar or granulation tissue which will respond more successfully to IL steroid injection.

Clinical characteristics of auricular keloids treated with surgical excision

Background and Objectives

Differences in morphology of auricular keloids possibly contribute to distinct results of treatment. The aim of this study was to evaluate clinical characteristics of the auricular keloids according to the modified Chang-Park classification and to compare the results of treatment including recurrence rate between the subgroups.

Subjects and Methods

Clinical data of 15 patients of auricular keloids were retrospectively reviewed. The keloids were classified according to modified Chang-Park classification. Clinical characteristics, the presence of recurrence, and the duration required for the recurrence were compared.

Results

Eight out of 15 patients (53.3%) were single sessile type (type II), followed by 4 patients of pedunculated type, 1 patient of multiple sessile type, 1 patient of buried type, and 1 patient of mixed type, respectively. Recurrent keloids after previous surgeries were noted in 7 out of 15 patients and most of them (6 of 7, 85.7%) were sessile type. Three patients who underwent surgery at our department showed recurrence.

Conclusions

The classification of auricular keloids according to morphologic patterns can assist surgeons in choosing the appropriate management.

Is There an Association between Keloids and Blood Groups?

Objective. The aim of the study is to investigate the possible associations between the blood groups ABO and Rhesus systems and the presence of keloids in patients with black skin. Method. This case-control study was conducted between September 2007 and August 2011 comparing dermatologic outpatients with keloids to matched controls recruited in preanesthetic consultation at Tokoin Teaching Hospital of Lomé (Togo). Results. The distribution of different ABO blood groups and Rhesus blood groups in both groups (cases versus controls) was not significantly different. This distribution of different blood groups was superimposed on the general population of blood donors at the National Blood Transfusion Center of Lomé. Univariate analysis between each blood group and the presence of keloid does not yield any statistically significant association between blood groups and presence of keloids in the subjects. Conclusion. The study shows no significant association between blood groups and the presence of keloids in our patients. Further investigation needs to be conducted to elucidate this hypothesis further by conducting multicenter studies of several ethnic groups.

Management of acne scarring, part II: a comparative review of non-laser-based, minimally invasive approaches

Acne scarring is a commonly encountered yet extremely challenging problem to treat for the dermatologist. As acne scarring can lead to significant psychological distress and low self-esteem, it is of utmost importance to have effective and satisfying treatments in the physician's armamentarium. However, many treatments are unsatisfying, leading to patient disappointment and frustration. Although early treatment of acne lesions and inflammation with isotretinoin is beneficial in preventing acne scarring, many patients still present with troubling noticeable scars. Despite the advances in pharmacology and technology, scar treatment still remains suboptimal and is tainted with several adverse effects. However, some treatments can provide benefits. This review article exhaustively discusses and analyzes the various minimally invasive approaches to the treatment of acne scarring with an emphasis on pharmacologic agents, such as isotretinoin for atrophic acne scars and corticosteroids and chemotherapeutic drugs for hypertrophic scars. Intralesional injections of corticosteroids are efficacious in reducing keloid scar formation in addition to preventing recurrence following surgical excision. In-office and minimally invasive procedural management, including chemical peels, dermabrasion, tissue augmentation, and punch excision is also discussed. Superficial chemical peels are efficacious in treating atrophic scars with relatively few adverse effects and complications. Although dermabrasion is used less often with the advent of laser resurfacing, this technique remains as a viable option for those with atrophic scars. Post-inflammatory hyperpigmentation can be managed successfully with topical agents such as azelaic acid and hydroquinone. The efficacy of various treatment modalities is highlighted with a focus on choosing the correct modalities for specific scar types.

Effectiveness of onion extract gel on surgical scars in asians

Background. Onion extracts have been shown in vitro to accelerate wound healing. Results from clinical studies on surgical scars in Caucasians were disappointing. The aim of this study is to evaluate the effectiveness of onion extract gel in improving the cosmetic and symptoms of surgical scars in Asians. Patients/Methods. Twenty Asians who had new Pfannenstiel's cesarean section scars were recruited in this prospective double-blinded, split-scar study. Each side was randomly assigned treatment with onion extract gel or placebo at 7 days after surgery. The product was applied three times daily for 12 weeks. Subjects were evaluated at baseline and 4th and 12th weeks. Scar redness was assessed by calorimeter, scar height and pliability were assessed by blinded investigators, and scar symptoms and overall cosmetic improvement were assessed by subjects. Results. Sixteen subjects completed the study. A statistically significant difference between two sides of scar in terms of scar height and scar symptoms was found. There was no statistically significant difference in scar redness, scar pliability, and overall cosmetic appearance between two sides. Conclusions. The early use of topical 12% onion extract gel on Pfannenstiel's cesarean section scar in Asians resulted in the improvement of scar height and scar symptoms.

FK506 inhibits the enhancing effects of transforming growth factor (TGF)-β1 on collagen expression and TGF-β/Smad signalling in keloid fibroblasts: implication for new therapeutic approach

BACKGROUND

  Keloid is a unique proliferative disorder of fibroblasts resulting from derailment of the typical wound healing process. Due to lack of animal models for therapeutic testing, treatment of keloids remains a clinical challenge. Transforming growth factor (TGF)-β1-related signalling plays a key role in keloid formation. As tacrolimus (FK506) has been reported to inhibit the effects of TGF-β1 on cultured fibroblasts, we hypothesized that FK506 may be useful in treating keloids.

OBJECTIVES

To explore the effects of FK506 on TGF-β1-stimulated keloid fibroblasts (KFs) in terms of proliferation, migration and collagen production and to investigate the regulatory pathways involved.

METHODS

Fibroblasts derived from keloids were treated with TGF-β1 with or without FK506. Relevant assays including 5-bromo-2'-deoxyuridine incorporation assay, in vitro scratch assay, reverse transcription-polymerase chain reaction (PCR), quantitative PCR and Western blotting were performed.

RESULTS

The proliferation and migration of KFs were significantly higher than those of normal fibroblasts. FK506 markedly inhibited KF proliferation, migration and collagen production enhanced by TGF-β1. The increase in TGF-β receptor I and II expression in TGF-β1-treated KFs was suppressed by FK506 treatment. TGF-β1 increased the phosphorylation of Smad2/3 and Smad4 in KFs, and this enhancing effect was abrogated by FK506. In addition, FK506 significantly increased the expression of Smad7 which was suppressed by TGF-β1 treatment.

CONCLUSIONS

Our results demonstrate that FK506 effectively blocks the TGF-β/Smad signalling pathway in KFs by downregulation of TGF-β receptors and suggest that FK506 may be included in the armamentarium for treating keloids.

Culture medium and cell density impact gene expression in normal skin and abnormal scar-derived fibroblasts

Fibroblasts, the main cell type of the dermis, are responsible for production and remodeling of extracellular matrix during wound healing. Disruption of either production or degradation of extracellular matrix can lead to abnormal scarring, resulting in hypertrophic scar or keloid scar. Aberrations in proliferation and gene expression have been observed in fibroblasts isolated from abnormal scars, but differences observed may be related to biologic responses to growth conditions and media formulations. This study examined gene expression in primary human fibroblasts from normal skin or abnormal scar in two culture media formulations and three relative cell densities. In general, higher expression of collagen type 1 alpha-1 (COL1A1) and alpha-2 (COL1A2) and matrix metalloproteinase 3 (MMP3) and lower levels of MMP1 were observed in all cell strains cultured in standard medium containing 10% fetal bovine serum compared with cells cultured in medium optimized for proliferation. Normal and scar-derived fibroblasts exhibited differences in gene expression in specific response to media formulations and cell density. COL1A1 and COL1A2 were increased, and MMP1 and MMP3 were decreased, in keloid cells compared with normal fibroblasts under most conditions analyzed. However, expression of plasminogen activator inhibitor 1 in keloid fibroblasts, which was significantly different than in normal fibroblasts, was either increased or decreased in response to the medium formulation and relative cell density. A related gene, plasminogen activator inhibitor 2, was shown for the first time to be significantly increased in keloid fibroblasts compared with normal fibroblasts, in both media formulations and at all three cell densities. The results emphasize the critical role of culture conditions in interpretation of cell behavior and expression data and for comparison of cells representing normal and fibrotic phenotypes.

Insights gained from the reverse engineering of gene networks in keloid fibroblasts

Background

Keloids are protrusive claw-like scars that have a propensity to recur even after surgery, and its molecular etiology remains elusive. The goal of reverse engineering is to infer gene networks from observational data, thus providing insight into the inner workings of a cell. However, most attempts at modeling biological networks have been done using simulated data. This study aims to highlight some of the issues involved in working with experimental data, and at the same time gain some insights into the transcriptional regulatory mechanism present in keloid fibroblasts.

Methods

Microarray data from our previous study was combined with microarray data obtained from the literature as well as new microarray data generated by our group. For the physical approach, we used the fREDUCE algorithm for correlating expression values to binding motifs. For the influence approach, we compared the Bayesian algorithm BANJO with the information theoretic method ARACNE in terms of performance in recovering known influence networks obtained from the KEGG database. In addition, we also compared the performance of different normalization methods as well as different types of gene networks.

Results

Using the physical approach, we found consensus sequences that were active in the keloid condition, as well as some sequences that were responsive to steroids, a commonly used treatment for keloids. From the influence approach, we found that BANJO was better at recovering the gene networks compared to ARACNE and that transcriptional networks were better suited for network recovery compared to cytokine-receptor interaction networks and intracellular signaling networks. We also found that the NFKB transcriptional network that was inferred from normal fibroblast data was more accurate compared to that inferred from keloid data, suggesting a more robust network in the keloid condition.

Conclusions

Consensus sequences that were found from this study are possible transcription factor binding sites and could be explored for developing future keloid treatments or for improving the efficacy of current steroid treatments. We also found that the combination of the Bayesian algorithm, RMA normalization and transcriptional networks gave the best reconstruction results and this could serve as a guide for future influence approaches dealing with experimental data.

Treatment of hypertrophic scars and keloids with a fractional CO2 laser: a personal experience

Keloids and hypertrophic scars are both abnormal wound responses in predisposed individuals but they differ in that keloids extend beyond the original wound and almost never regress, while hypertrophic scars remain within the original wound and tend to regress. How keloids grow is not totally clear because there is no animal model; in fact, keloids affect only humans. Different injuries can result in keloids, including burns, surgery, ear piercing, lacerations, abrasions, tattooing, vaccinations, injections, insect bites and any process causing skin inflammation (chicken pox, acne, folliculitis, zoster). Skin or wound tension is considered a critical factor in the formation of keloids and hypertrophic scars. This study is based on eight consecutive patients (four females and four males, F:M = 1:1) with a total of 12 keloids. All of whom were treated monthly with a MiXto SX CO(2) laser, using 13 W of power, 8 SX of index and 40% coverage (density) in combination with Same Plast Gel(®) twice a day. Each scar required 12 treatments, and all the patients, followed up for 1 year after the last treatment, had optimum results and no recurrence.

Scar tissue

PURPOSE OF REVIEW

To examine the place of surgery and other modes of treating scar tissue given the plethora of measures that are advocated on the internet.

RECENT FINDINGS

There is good evidence to support the use of silicone sheets, pulsed dye laser (PDL), intralesional triamcinolone and dermabrasion in reducing hypertrophic scars, but each needs qualifying in terms of their timing and the type of scar tissue that they are used for.

SUMMARY

The surgical revision of scars should be delayed for at least 12 months unless there is webbing when redistributing skin tension forces with a Z-plasty or multiple Z-plasties or other local flaps negates the need to wait for the scar to mature. In a posttraumatic 'horse shoe' shaped, or a very oblique, cut an irregular contour is likely to occur. Under these circumstances a triamcinolone injection into any raised area can help and this needs to be re-evaluated after 6 weeks. With a less irregular contour dermabrasion can help if used 8 weeks after surgery. With hypertrophic scarring both silicone gel sheeting and PDL may help reduce the prominence of the scar. Most of all time helps scars to settle and fade and typical scar maturation takes 18-24 months. The role of stem cells, particularly from adipose tissue, warrants further study.

Acne scars: pathogenesis, classification and treatment

Acne has a prevalence of over 90% among adolescents and persists into adulthood in approximately 12%-14% of cases with psychological and social implications. Possible outcomes of the inflammatory acne lesions are acne scars which, although they can be treated in a number of ways, may have a negative psychological impact on social life and relationships. The main types of acne scars are atrophic and hypertrophic scars. The pathogenesis of acne scarring is still not fully understood, but several hypotheses have been proposed. There are numerous treatments: chemical peels, dermabrasion/microdermabrasion, laser treatment, punch techniques, dermal grafting, needling and combined therapies for atrophic scars: silicone gels, intralesional steroid therapy, cryotherapy, and surgery for hypertrophic and keloidal lesions. This paper summarizes acne scar pathogenesis, classification and treatment options.

Effects of low-level laser therapy on pain and scar formation after inguinal herniation surgery: a randomized controlled single-blind study

OBJECTIVE

The aim of this study was to investigate the efficacy of an infrared GaAlAs laser operating with a wavelength of 830 nm in the postsurgical scarring process after inguinal-hernia surgery.

BACKGROUND

Low-level laser therapy (LLLT) has been shown to be beneficial in the tissue-repair process, as previously demonstrated in tissue culture and animal experiments. However, there is lack of studies on the effects of LLLT on postsurgical scarring of incisions in humans using an infrared 830-nm GaAlAs laser.

METHOD

Twenty-eight patients who underwent surgery for inguinal hernias were randomly divided into an experimental group (G1) and a control group (G2). G1 received LLLT, with the first application performed 24 h after surgery and then on days 3, 5, and 7. The incisions were irradiated with an 830-nm diode laser operating with a continuous power output of 40 mW, a spot-size aperture of 0.08 cm(2) for 26 s, energy per point of 1.04 J, and an energy density of 13 J/cm(2). Ten points per scar were irradiated. Six months after surgery, both groups were reevaluated using the Vancouver Scar Scale (VSS), the Visual Analog Scale, and measurement of the scar thickness.

RESULTS

G1 showed significantly better results in the VSS totals (2.14 +/- 1.51) compared with G2 (4.85 +/- 1.87); in the thickness measurements (0.11 cm) compared with G2 (0.19 cm); and in the malleability (0.14) compared with G2 (1.07). The pain score was also around 50% higher in G2.

CONCLUSION

Infra-red LLLT (830 nm) applied after inguinal-hernia surgery was effective in preventing the formation of keloids. In addition, LLLT resulted in better scar appearance and quality 6 mo postsurgery.

Silicone-based scar therapy: a review of the literature

Hypertrophic and keloid scars still are among the banes of plastic surgery. In the treatment arsenal at the disposal of the plastic surgeon, topical silicone therapy usually is considered the first line of treatment or as an adjuvant to other treatment methods. Yet, knowledge concerning its mechanisms of action, clinical efficacy, and possible adverse effects is rather obscure and sometimes conflicting. This review briefly summarizes the existing literature regarding the silicone elastomer's mechanism of action on scars, the clinical trials regarding its efficacy, a description of some controversial points and contradicting evidence, and possible adverse effects of this treatment method. Topical silicone therapy probably will continue to be the preferred first-line treatment for hypertrophic scars due to its availability, price, ease of application, lack of serious adverse effects, and relative efficacy. Hopefully, future randomized clinical trials will help to clarify its exact clinical efficacy and appropriate treatment protocols to optimize treatment results.

Effect of a calcium-channel blocker (verapamil) on the morphology, cytoskeleton and collagenase activity of human skin fibroblasts

The effects of verapamil modulating collagen biosynthesis have prompted us to study the role of this drug in cultured fibroblasts. In this article, we describe the effects of verapamil on fibroblast behaviour, with special emphasis to phenotypic modifications, reorganisation of actin filaments and secretion of MMP1. Human dermal fibroblasts treated with 50-μM verapamil changed their normal spindle-shaped morphology to stellate. Treated cells showed discrete reorganisation of actin filaments, as revealed by fluorescein isothiocyanate (FITC)-phalloidin staining and confocal microscopy. We hypothesised that these effects would be associated to lower levels of cytosolic Ca(2+). Indeed, short time loading with calcium green confirmed that verapamil-treated fibroblasts exhibited lower intracellular calcium levels compared to controls. We also observed that verapamil increases the secretion of MMP1 in cultured fibroblasts, as demonstrated by zymography, specific substrate assays and immunoblot. The morphological alterations induced by verapamil are neither cytotoxic nor associated with other dramatic cytoskeleton alterations. Thus we may conclude that this drug enhances collagenase secretion and does not disrupt the major tracks necessary to deliver these enzymes in the extracellular space. The present results suggested that verapamil could be used at physiological levels to enhance collagen I breakdown, and may be considered a potential candidate for intralesional therapy of wound healing and fibrocontractive diseases.

The emerging role of antineoplastic agents in the treatment of keloids and hypertrophic scars: a review

The management of keloids and hypertrophic scars continues to challenge health-care providers. Though both forms of pathologic scarring are distinct entities at the macro and microscopic level, their etiologies and treatment are often similar. Potential treatment approaches are progressing, and combinations of treatment options have been proposed in the literature with promising outcomes. The treatment evolution has reached a level where molecular therapeutic modalities are being investigated. Currently, no gold standard treatment exists. Overall success rates and patient satisfaction seem to be slowly climbing, but additional investigational studies must continue to be performed. Several studies have investigated antineoplastic agents, and there seems to be a marked improvement in rates of recurrence, patient satisfaction, and overall quality of scar when these agents are used. Intralesional injection and/or wound irrigation with interferon-a2b, interferon-g, mitomycin-C, bleomycin, or 5-fluorouracil seems to have a positive effect on the reduction of pathologic scars. There is mounting evidence that these drugs used alone or in combination therapy, have the potential to be an integral part of the treatment paradigm for hypertrophic scars and keloids.

595-nm long pulsed dye laser and 1450-nm diode laser in combination with intralesional triamcinolone/5-fluorouracil for hypertrophic scarring following a phenol peel

Hypertrophic scars and keloids are a therapeutic challenge because of the low response to treatment and recurrences after treatment. A variety of treatment regimens have been used with different degrees of success, with no universally accepted treatment protocol resulting in their complete and permanent resolution. We offer this case to demonstrate a combination approach for the treatment of hypertrophic scarring. A 75-year-old woman (with Fitzpatrick skin type II) presented with a 4-month history of scarring, which had developed following a phenol peel for perioral rhytides. The patient underwent 10 treatment sessions with the 595-nm long-pulsed dye laser followed immediately by the 1450-nm diode laser in combination with intralesional triamcinolone and 5-fluorouracil. After the fifth treatment session, about 90% improvement was noted; at the last treatment session, greater than 95% overall improvement was noted. Two and a half years after the last treatment session, the patient and treating physician noted no regression. A limitation of this therapy is that the combination approach makes it difficult to determine what individual contributions each treatment modality had on the final result. We have illustrated a successful multifaceted treatment regimen for hypertrophic scars and keloids using a combination approach.

Hypertrophic versus non hypertrophic scars compared by immunohistochemistry and laser confocal microscopy: type I and III collagens

Although dermal collagens appear increased in hypertrophic scars, this has not been tested in tissue samples using objective methods. We compared the expression of types I and III collagen in hypertrophic and non hypertrophic scars at 6-12 and 18-24 months after burn using a quantitative method. Among 17 patients with extensive burns, 3 patients had acute scars, 8 had hypertrophic or non hypertrophic scars at 6-12 months after burn and 6 had hypertrophic or non hypertrophic scars at 18-24 months after burn. After clinical assessment of scars using the Vancouver scale, immunohistochemistry for types I and III collagens was performed. Images were captured with a laser scanning confocal microscope and the relative amounts of types I and III collagens were determined in superficial and deep dermis. The effects of time and scar type were assessed using two-way analysis of variance (ANOVA) and Tukey's test. Collagen III scar/normal ratios were higher in hypertrophic scars at both time points (P = 0.05). There were no differences in collagen I scar/normal ratios. Large variation was observed in scars during the acute phase regarding the expression of collagens. Easily accessed by immunohistochemistry and confocal microscopy, type III collagen deposition may help in determining scar phenotype, differentiating hypertrophic and non hypertrophic scars.

CBL is frequently altered in lung cancers: its relationship to mutations in MET and EGFR tyrosine kinases

The mechanisms of hypertrophic scar formation are not fully understood. We previously screened the differentially expressed genes of human hypertrophic scar tissue and identified P311 gene as upregulated. As the activities of P311 in human fibroblast function are unknown, we examined the distribution of it and the effects of forced expression or silencing of expression of P311. P311 expression was detected in fibroblast-like cells from the hypertrophic scar of burn injury patients but not in peripheral blood mononuclear cells, bone marrow mesenchymal stem cells, epidermal cells or normal skin dermal cells. Transfection of fibroblasts with P311 gene stimulated the expression of alpha-smooth muscle actin (α-SMA), TGF-β1 and α1(I) collagen (COL1A1), and enhanced the contraction of fibroblast populated collagen lattices (FPCL). In contrast, interference of fibroblast P311 gene expression decreased the TGF-β1 mRNA expression and reduced the contraction of fibroblasts in FPCL. These results suggest that P311 may be involved in the pathogenesis of hypertrophic scar via induction of a myofibroblastic phenotype and of functions such as TGF-β1 expression. P311 could be a novel target for the control of hypertrophic scar development.

Scoring of collagen organization in healthy and diseased human dermis by multiphoton microscopy

We have used nonlinear imaging to evaluate collagen organization in connective tissue ex-vivo samples. Image analysis methods were tested on healthy dermis, normal scars, and keloids. The evaluation of the second harmonic to autofluorescence aging index of dermis (SAAID) has allowed a first characterization of tissues by scoring the collagen/elastin content. Further analyses on collagen morphology in healthy dermis and keloids were performed by image-pattern analysis of SHG images. The gray-level co-occurrence matrix (GLCM) analysis method has allowed classification of different tissues based on the evaluation of geometrical arrangement of collagen fibrillar bundles, whereas a pattern analysis of the FFT images has allowed the discrimination of different tissues based on the anisotropy of collagen fibers distribution. This multiple scoring method represents a promising tool to be extended to other collagen disorders, as well as to be used in in-vivo skin-imaging applications.

Molecular dissection of abnormal wound healing processes resulting in keloid disease

Keloids are locally aggressive scars that typically invade into healthy surrounding skin and cause both physical and psychosocial distress to the patient. These pathological scars occur following minimal skin trauma after a variety of causes including burns and trauma. Although the pathogenesis of keloid disease is not well understood, it is considered to be the end product of an abnormal healing process. The aim of this review was to investigate the molecular and cellular pathobiology of keloid disease in relation to the normal wound healing process. The molecular aberrances in keloids that correlate with the molecular mechanisms in normal wound healing can be categorized into three groups: (1) extracellular matrix proteins and their degradation, (2) cytokines and growth factors, and (3) apoptotic pathways. With respect to cellular involvements, fibroblasts are the most well-studied cell population. However, it is unclear whether the fibroblast is the causative cell; they are modulated by other cell populations in wound repair, such as keratinocytes and macrophages. This review presents a detailed account of individual phases of the healing process and how they may potentially be implicated in aberrant raised scar formation, which may help in clarifying the mechanisms involved in keloid disease pathogenesis.

Safety and effectiveness of hyaluronic acid fillers in skin of color

OBJECTIVES

To assess the safety and effectiveness of hyaluronic acid (HA) fillers in skin of color.

METHODS

Two prospective studies followed up subjects with Fitzpatrick skin phototypes of IV, V, or VI for 24 weeks after dermal filler injections. In a double-blind, randomized study, subjects were injected with one of three high concentration (24 mg/mL) HA fillers (Juvéderm Ultra, Ultra Plus, and 30) in one nasolabial fold and Zyplast collagen in the other. In an open-label, randomized study, subjects received one of three low concentration (5.5 mg/mL) HA fillers (Hylaform, Hylaform Plus, and Captique) in both nasolabial folds.

RESULTS

A total of 160 subjects (a subset of 439 study subjects) were randomized and treated with one of the three high concentration fillers, and 119 subjects were randomized and treated with one of the three low concentration fillers. For subjects treated with the high concentration fillers there were no occurrences of hypersensitivity or hypertrophic scarring, and no increased incidence of hyperpigmentation or hypopigmentation in non-Caucasian vs. Caucasian subjects. For subjects treated with the low concentration fillers there were no occurrences of keloid formation, hypertrophic scarring, hypopigmentation, hypersensitivity, and three instances of mild hyperpigmentation. For all of the fillers the majority of subjects maintained >/=1 point improvement in nasolabial fold severity scores through 24 weeks.

CONCLUSIONS

All of the HA fillers were well tolerated in individuals with skin of color and demonstrated effectiveness throughout the 24 week period. Furthermore, the fillers provided smooth, natural-looking wrinkle correction in darker skin types.

Matrix metalloproteinase-2 and -9 activities in human keloids, hypertrophic and atrophic scars: a pilot study

Proteolytic degradation of extracellular matrix is one of the principal features of cutaneous wound healing but little is known about the activities of gelatinases; matrix metalloproteinase-2 (MMP-2) and matrix metalloproteinase-9 (MMP-9) on abnormal scar formation. The aim of this study is to determine collagen levels and the gelatinase activities in tissue from hypertrophic scars, atrophic scars, keloids and donor skin in 36 patients and 14 donors. Gelatinase levels (proenzyme + active enzyme) were determined by ELISA and their activities by gelatin zymography. MMP-9 activity was undetectable in gelatin zymography analysis. Pro-MMP-2 levels (median) were highest in normal skin group 53.58 (36.40-75.11) OD microg(-1) protein, while active MMP-2 levels were highest in keloid group 52.53 (42.47-61.51) OD microg(-1) protein. The active/pro ratio was the highest in keloid group 0.97 followed by hypertrophic scar, normal skin and atrophic scar groups 0.69 > 0.54 > 0.48, respectively. According to results of our study, the two-phase theory of the duration of hypertrophic scar and keloid formation can be supported by the data of tissue collagen and gelatinase analysis. This study is the first to relate scar formation relationship in regard to gelatinase activation ratio in a keloid, hypertrophic and atrophic scar patient group which is chosen appropriate in age and sex.

Hypertrophic scars and keloids--a review of their pathophysiology, risk factors, and therapeutic management

BACKGROUND

Hypertrophic scars and keloids result from an abnormal fibrous wound healing process in which tissue repair and regeneration-regulating mechanism control is lost. These abnormal fibrous growths present a major therapeutic dilemma and challenge to the plastic surgeon because they are disfiguring and frequently recur.

OBJECTIVE

To provide updated clinical and experimental information on hypertrophic scars and keloids so that physicians can better understand and properly treat such lesions.

METHODS

A Medline literature search was performed for relevant publications and for diverse strategies for management of hypertrophic scars and keloids.

CONCLUSION

The growing understanding of the molecular processes of normal and abnormal wound healing is promising for discovery of novel approaches for the management of hypertrophic scars and keloids. Although optimal treatment of these lesions remains undefined, successful healing can be achieved only with combined multidisciplinary therapeutic regimens.

Prevention and management of hypertrophic scars and keloids after burns in children

Hypertrophic scars and keloids are challenging to manage, particularly as sequelae of burns in children in whom the psychologic burden and skin characteristics differ substantially from adults. Prevention of hypertrophic scars and keloids after burns is currently the best strategy in their management to avoid permanent functional and aesthetical alterations. Several actions can be taken to prevent their occurrence, including parental and children education regarding handling sources of fire and flammable materials, among others. Combination of therapies is the mainstay of current burn scar management, including surgical reconstruction, pressure therapy, silicon gels and sheets, and temporary garments. Other adjuvant therapies such as topical imiquimod, tacrolimus, and retinoids, as well as intralesional corticosteroids, 5-fluorouracil, interferons, and bleomycin, have been used with relative success. Cryosurgery and lasers have also been reported as alternatives. Newer treatments aimed at molecular targets such as cytokines, growth factors, and gene therapy, currently in developing stages, are considered the future of the treatment of postburn hypertrophic scars and keloids in children.

Safe and effective treatment of problem scars with the purely thermal non-ablative Er:YAG laser scar mode

INTRODUCTION

Traumatic events as well as surgery can cause a large variety of scars, which are often a major psychological concern to patients. Moreover, patients often report itching or burning sensations as well as pain. We investigated the efficacy of purely non-ablative laser therapy in order to improve the appearance and quality of these scars.

METHODS

A total of 62 patients with problem scars were enrolled in the study. The purely thermal, non-ablative scar mode of an Er:YAG laser (BURANE XL; Wavelight AG, Erlangen, Germany) was used. One to six treatment sessions were performed. The improvement of scar redness, scar flatness, scar quality, itching and burning sensations as well as pain and patient satisfaction were evaluated.

RESULTS

The overall scar quality improved in 93% of patients. Similarly, the flatness improved in 89% of scars, itching sensation in 79% and burning sensation in 86% of patients. In 91% of scars a decrease of scar redness was seen and all painful scars showed a pain reduction. Average patient satisfaction was 7.4 on a 10-point scale. Sixty-one patients would recommend the therapy to another person. Side effects were limited to transient erythema and oedema.

CONCLUSION

The high success rate combined with the low side-effects resulted in high patient satisfaction. Post-traumatic or post-surgical scars can safely and effectively be treated by the thermal scar mode of the Er:YAG laser used.

[Therapy of keloids]

Keloids are benign fibrous growths that appear after surgery, trauma or "spontaneously" as a consequence of microtrauma in predisposed patients. Keloids are distinguished from hypertrophic scars in that keloids extend beyond the margins of the original wound and do not tend to regress spontaneously. Keloids are often associated with pruritus and pain and can lead to functional and cosmetic deformities. Keloids are a therapeutic challenge for the dermatologist; although multiple treatment options are available, a reliably effective approach with few side effects remains elusive. High quality research in evaluating keloid therapy is also lacking. This article summarizes the methods used for the treatment of keloids showing their advantages and disadvantages.

Adjuvant radiation of bilateral postauricular keloids: an illustration of technique

Treatment of keloids can be diverse and, frequently, in cases of recurrence, patients are referred for postoperative radiation therapy. Some sites known for keloid formation, such as the postauricular surface, can create a technical challenge. Because of the need for treatment so soon after surgery, physical manipulation of the freshly operated area to accommodate exposure for electron (or other) therapy is difficult. We were recently asked to evaluate a patient requiring treatment of both postauricular spaces. Literature describing techniques for such a case is scant, and we felt it would be helpful to describe and depict our setup and treatment course.