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Background: Research into the treatment of hypertrophic burn scar is hampered by the variability and subjectivity of existing outcome measures. This study aims to measure the inter- and intra-rater reliability of a panel of subjective and objective burn scar measurement tools., Methods: Three independent assessors evaluated 55 scar and normal skin sites using subjective (modified Vancouver Scar Scale [mVSS] & Patient and Observer Scar Assessment Scale [POSAS]) and objective tools. The intra-class correlation coefficient was utilised to measure reliability (acceptable when >0.70). Patient satisfaction with the different tools and scar parameter importance were assessed via questionnaires., Results: The inter-rater reliabilities of the mVSS and POSAS were below the acceptable limit. For erythema and pigmentation, all of the Scanoskin and DSM II measures (except the b* value) had acceptable to excellent intra and inter-rater reliability. The Dermascan ultrasound (dermal thickness, intensity) had excellent intra- and inter-rater reliability (>0.90). The Cutometer R0 (firmness) had acceptable reliability but not R2 (gross elasticity). All objective measurement tools had good overall satisfaction scores. Patients rated scar related pain and itch as more important compared to appearance although this finding was not sustained when corrected for multiple comparisons., Conclusion: The objective scar measures demonstrated acceptable to excellent intra- and inter-rater reliability and performed better than the subjective scar scales., (Copyright © 2019 The Authors. Published by Elsevier Ltd.. All rights reserved.)

Purpose: This cross-sectional study aimed to investigate whether adipose tissue loss and reduced vitamin D levels following severe burn injury are associated with pathologic scar formation and biomechanical scar properties., Methods: A total of 492 male subjects with hypertrophic burn scars were enrolled from January 2014 to July 2018 and analyzed. Body fat content was measured using dual-energy X-ray absorptiometry. Values of melanin, erythema, and trans-epidermal water loss (TEWL) and the distensibility and elasticity of hypertrophic scars were examined using pigment- and TEWL-measuring devices and a suction skin elasticity meter., Results: Burn patients with higher fat percentage tended to have higher 25(OH) vitamin D levels (P < 0.001). As body fat percentage increased, hypertrophic scars showed higher mean value of Uf (distensibility, P < 0.001) and lower mean value of Uv/Ue (viscoelasticity or interstitial fluid shifting, P < 0.001). Burn patients with higher 25(OH) vitamin D levels tended to have higher mean values of Uf (P < 0.001) and Ua/Uf (gross elasticity, P = 0.013) and lower mean value of Uv/Ue (P = 0.008)., Conclusion: Adipose tissue loss and decreased 25(OH) vitamin D levels following burn injury were related to scar rigidity and slow interstitial fluid shifting in hypertrophic scars., (Copyright © 2019 Elsevier Ltd and ISBI. All rights reserved.)

Hypertrophic scars are dermal fibrosis diseases that protrude from the surface of the skin and irregularly extend to the periphery, seriously affecting the appearance and limb function of the patient. In this study, we found that microRNA-130a (miR-130a) was increased in hypertrophic scar tissues and derived primary fibroblasts, accompanied by up-regulation of collagen1/3 and α-SMA. Inhibition of miR-130a in hypertrophic scars fibroblasts suppressed the expression of collagen1/3 and α-SMA as well as the cell proliferation. Bioinformatics analysis combined with luciferase reporter gene assay results indicated that CYLD was a target gene of miR-130a, and the miR-130a mimic could reduce the level of CYLD. In contrast to miR-130a, the expression of CYLD was downregulated in hypertrophic scars and their derived fibroblasts. Overexpressing CYLD inhibited the expression of collagen 1/3 and α-SMA, slowed cell proliferation, and inhibited Akt activity. As expected, further study showed that the overexpression of CYLD could prevent the pro-fibroproliferative effects of miR-130a. Consistent with the in vitro results, the inhibitor of miR-130a effectively ameliorated excessive collagen deposition in bleomycin-induced skin fibrosis mouse model. Taken together, our results indicate that miR-130a promotes collagen secretion, myofibroblast transformation and cell proliferation by targeting CYLD and enhancing Akt activity. Therefore, the miR-130a/CYLD/Akt pathway may serve as a novel entry point for future skin fibrosis research., (Copyright © 2019 Elsevier Inc. All rights reserved.)

After similar extent of injury there is considerable variability in scarring between individuals, in part due to genetic factors. This study aimed to identify genetic variants associated with scar height and pliability after burn injury. An exome-wide array association study and gene pathway analysis were performed on a prospective cohort of 665 patients treated for burn injury. Outcomes were scar height (SH) and scar pliability (SP) sub-scores of the modified Vancouver Scar Scale (mVSS). DNA was genotyped using the Infinium ® HumanCoreExome-24 BeadChip. Associations between genetic variants (single nucleotide polymorphisms) and SH and SP were estimated using an additive genetic model adjusting for age, sex, number of surgical procedures and % total body surface area of burn in subjects of European ancestry. No individual genetic variants achieved the cut-off threshold of significance. Gene regions were analysed for spatially correlated single nucleotide polymorphisms and significant regions identified using comb-p software. This gene list was subject to gene pathway analysis to find which biological process terms were over-represented. Using this approach biological processes related to the nervous system and cell adhesion were the predominant gene pathways associated with both SH and SP. This study suggests genes associated with innervation may be important in scar fibrosis. Further studies using similar and larger datasets will be essential to validate these findings., (Copyright © 2018 Elsevier Ltd and ISBI. All rights reserved.)

Background: One objective of massage therapy applied to hypertrophic scar (HSc), is to improve the structural properties so skin possesses the strength and elasticity required for normal mobility. However, research supporting this effect is lacking. The objective of this study was to characterize the changes in scar elasticity, erythema, melanin, and thickness immediately after a massage therapy session and after a 12-week course of treatment compared to intra-individual matched control scars., Methods: We conducted a prospective, randomized, single-blinded, pragmatic, controlled, clinical trial evaluating the impact of a 12-week course of massage therapy. Seventy burn survivors consented to participate and 60 completed the study. Two homogeneous, intra-individual scars were randomized to usual care control or massage therapy plus usual care. Massage, occupational or physical therapists provided massage treatment 3x/week for 12 weeks. Scar site characteristics were evaluated weekly immediately before and after massage treatment including elasticity (Cutometer), erythema and melanin (Mexameter), and thickness (high-frequency ultrasound). Analysis of covariance (ANCOVAs) were performed to test for immediate and long-term treatment effects. A mixed-model approach was used to account for the intra-individual scars., Results: Scar evaluation immediately before and after massage therapy at each time point revealed changes for all scar characteristics, but the group differences were predominantly present during the early weeks of treatment. The within group long-term analysis revealed a significant increase in elasticity, and a reduction in thickness, during the 12-week treatment period for both the control scar (CS) and massage scar (MS). The increase in elasticity reached significance at week 8 for the MS and week 10 for the CS and the reduction in thickness at week 5 for the CS and week 7 for the MS. There was no significant within group long-term differences for either erythema or melanin. There were group differences in erythema at week 8 and 11 where the CS was less erythematous than the MS., Conclusions: The immediate impact of forces applied during massage therapy may lead patients and therapists to believe that there are long-term changes in elasticity, erythema, and pigmentation, however, once baseline measures, the control scar, and time were incorporated in the analysis there was no evidence of long-term benefit. Massage therapy applied with the objective of increasing scar elasticity or reducing erythema or thickness over the long-term should be reconsidered., (Copyright © 2018 Elsevier Ltd and ISBI. All rights reserved.)

A large-scale online survey was designed to both inform and direct the development of an online community healthcare hub for people living with scarring. Focussed areas of questioning were generated to gather information on psychological symptoms, scar support and knowledge of wounds and healing. Simple statistical data was produced on the severity, aetiology and location of scarring. A secondary data analysis of the survey responses was conducted on more focussed themes. This survey was completed by 1034 people living with scars, 119 of which had burn scarring. The results highlight that patients with burn scars have higher levels of pre-existing psychological difficulties, carry a greater number of scars and experience more symptoms. A lack of support is identified for patients with scars once they have been discharged by their healthcare provider. The most popular forms of support were chosen as face-to-face interaction or online support. Key areas of support were found to be psychology particularly for help with acceptance or coping methods, wound care advice and meeting with other patients with scars. For these patients, key themes in the psychological impact of scarring include appearance-related concerns, social anxiety, acceptance and coping, experience of symptoms, skin viability and survivorship., (Crown Copyright © 2018. Published by Elsevier Ltd. All rights reserved.)

Background: This study aimed to evaluate cross-cultural adaptation, validation, and reliability of Patient and Observer Scar Assessment Scale (POSAS) for its Turkish use., Method: This study included 50 burn patients with hypertrophic scars who were aged 18-65 years (mean, 37.5±1.4years) and were admitted to Wound and Burn Treatment Center from February 2014 to April 2014. With regard to the cultural adaptation of POSAS from English to Turkish, the scale was translated by two people who worked in different health fields. POSAS was administered to the patients with a 1-week interval to evaluate the validity and reliability of the scale. Internal consistency of the scale was tested using the Cronbach alphamethod., Results: The Cronbach alpha value for the observer measurements was found to be 0.93 (excellent), and that for patient measurements was found to be 0.77 (good). Accordingly, the internal consistency of the scale was established., Conclusion: The Turkish version of POSAS is a valid, reliable and culturally appropriate survey for evaluating hypertrophic scars. We believe that the Turkish version of POSAS will be an important clinical/scientific tool in the field of burn physiotherapy in Turkey, which will lead to new researches in this field., (Copyright © 2018 Elsevier Ltd and ISBI. All rights reserved.)

Background: In hypertrophic scar assessment, laser Doppler imaging (LDI), colorimetry and subjective assessment (POSAS) can be used to evaluate blood flow, erythema and redness, respectively. In addition, the microvasculature (i.e. presence of microvessels) can be determined by immunohistochemistry. These measurement techniques are frequently used in clinical practice and/or in research to evaluate treatment response and monitor scar development. However, until now it has not been tested to what extent the outcomes of these techniques are associated, whilst the outcome terms are frequently used interchangeably or replaced by the umbrella term 'vascularization'. This is confusing, as every technique seems to measure a specific feature. Therefore, we evaluated the correlations of the four measurement techniques., Methods: We included 32 consecutive patients, aged ≥18 years, who underwent elective resection of a hypertrophic scar. Pre-operatively, we performed LDI (measuring blood flow), colorimetry (measuring erythema) and the POSAS (subjective redness) within the predefined scar area of interest (∼1.5cm). Subsequently, the scar was excised and the area of interest was sent for immunohistochemistry, to determine the presence of microvessels., Results: Only a statistically significant correlation was found between erythema values (colorimetry) and subjective redness assessment (POSAS) (r=0.403, p=0.030). We found no correlations between the outcomes of LDI, immunohistochemistry and colorimetry., Conclusions: Blood flow, the presence of microvessels and erythema appear to be different hypertrophic scar features because they show an absence of correlation. Therefore, in the field of scar assessment, these outcome terms cannot be used interchangeably. In addition, we conclude that the term 'vascularization' does not seem appropriate to serve as an umbrella term. The use of precise definitions in research as well as in clinical practice is recommended., (Copyright © 2017 Elsevier Ltd and ISBI. All rights reserved.)

Improvements in acute burn care have enabled patients to survive massive burns that would have once been fatal. Now up to 70% of patients develop hypertrophic scars after burns. The functional and psychosocial sequelae remain a major rehabilitative challenge, decreasing quality of life and delaying reintegration into society. Approaches to optimise healing potential of burn wounds use targeted wound care and surgery to minimise the development of hypertrophic scarring. Such approaches often fail, and modulation of the established scar is continued although the optimal indication, timing, and combination of therapies have yet to be established. The need for novel treatments is paramount, and future efforts to improve outcomes and quality of life should include optimisation of wound healing to attenuate or prevent hypertrophic scarring, well-designed trials to confirm treatment efficacy, and further elucidation of molecular mechanisms to allow development of new preventive and therapeutic strategies., (Copyright © 2016 Elsevier Ltd. All rights reserved.)

Children have specific characteristics of wound healing. The aim of this study was to describe the specific clinical characteristics of wounds healing in children and to present the current knowledge on the specific mechanisms with regard to infant age. The tissue insult or injury in fetus can heal without scar, mainly due to reduced granulation tissue associated to diminished or even no inflammatory phase, modified extracellular matrix such as the concentration of hyaluronic acid in amniotic liquid, expression and arrangement of collagen and tenascin. Thickness of children skin is a serious negative factor in case of trauma, whereas poor co-morbidities and efficient growth tissue mechanisms are beneficial to good evolution, even in cases of extensive damage and loss of tissue. The subsequent tissue mechanical forces, wound healing during childhood, spanning from the age of 2 until the end of puberty, is associated with more hypertrophic scars, both in duration and in intensity. Consequently, unnecessary surgery has to be avoided during this period when possible, and children with abnormal or pathologic wound healing should benefit from complementary treatments (hydration, massage, brace, silicone, hydrotherapy…), which represent efficient factors to minimize tissue scarring. After wound healing, the growth body rate can be responsible for specific complications, such as contractures, alopecia, and scar intussusceptions. Its evolutionary character implies the need of an attentive follow-up until adult age. Psychologic repercussions, as a consequence of pathologic scars, must be prevented and investigated by the surgeon., (Copyright © 2016 Elsevier Masson SAS. All rights reserved.)

Animal models are crucial for the study of fibrosis. Keloids represent a unique type of fibrotic scarring that occurs only in humans, thus presenting a challenge for those studying the pathogenesis of this disease and its therapeutic options. Here, several animal models of fibrosis currently in use are described, emphasizing recent progress and highlighting encouraging challenges., (Copyright © 2016 International Society of Matrix Biology. Published by Elsevier B.V. All rights reserved.)

The cutaneous wound-healing process can lead to hypertrophic scar formation, during which exaggerated inflammation has been demonstrated to have an important role. Therefore, an exploration of strategies designed to regulate this inflammatory process is warranted. Mesenchymal stem cells (MSCs) have recently been demonstrated to regulate inflammation in various diseases. In this regard, using a rabbit model, we locally injected human mesenchymal stem cells (hMSCs) derived from bone marrow to treat hypertrophic scar formation, and explored their underlying mechanisms. We found that hMSC therapy efficiently regulated inflammation and prevented scar formation. We attributed the therapeutic effects of hMSCs to their secretion of an anti-inflammatory protein, TNF-alpha-stimulated gene/protein 6 (TSG-6). Unexpectedly, after injection, the number of surviving hMSCs decreased markedly and the hMSCs underwent extensive apoptosis, which was demonstrated to promote their secretion of TSG-6, partially through the activation of caspase-3. Moreover, H2O2-induced apoptotic hMSCs showed higher inflammatory regulatory abilities. The inhibition of caspase-3 decreased the inflammatory regulatory abilities of hMSCs and attenuated their therapeutic effects. Our results demonstrate that hMSCs can efficiently prevent hypertrophic scar formation via inflammatory regulation. In addition, we found that apoptosis has an important role in the activation of the inflammatory regulatory abilities of hMSCs.

Despite the worldwide use of silicones in scar management, its exact working mechanism based on a balanced occlusion and hydration, is still not completely elucidated. Moreover, it seems peculiar that silicones with completely different occlusive and hydrating properties still could provide a similar therapeutic effect. The objective of the first part of this study was to compare the occlusive and hydrating properties of three fluid silicone gels and a hydrating gel-cream. In a second part of the study these results were compared with those of silicone gel sheets. Tape stripped skin was used as a standardized scar like model on both forearms of 40 healthy volunteers. At specific times, trans epidermal water loss (TEWL) and the hydration state of the stratum corneum were measured and compared with intact skin and a scar-like control over a 3-4h period. Our study clearly demonstrated that fluid silicone gels and a hydrating gel-cream have comparable occlusive and hydrating properties while silicone gel sheets are much more occlusive, reducing TEWL values far below those of normal skin. A well-balanced, hydrating gel-cream can provide the same occlusive and hydrating properties as fluid silicone gels, suggesting that it could eventually replace silicones in scar treatment., (Copyright © 2013 Elsevier Ltd and ISBI. All rights reserved.)

Objective: After burn injuries, scarred skin lacks elasticity, especially in hypertrophic scars. Topical treatment with tretinoin can improve the appearance and quality of the skin (i.e., texture, distensibility, color, and hydration). The objective of this prospective study was to examine the effects of treatment with 0.05% tretinoin for one year on the biomechanical behavior and histological changes undergone by facial skin with post-burn scarring., Setting: Tertiary, Institutional., Method: Fifteen female patients who had suffered partial thickness burns with more than two years of evolution were selected. Skin biopsies were obtained initially and after one year of treatment. The resistance and elastance of these skin biopsies were measured using a mechanical oscillation analysis system. The density of collagen fibers, elastic fibers, and versican were determined using immunohistochemical analysis., Results: Tretinoin treatment significantly lowered skin resistance and elastance, which is a result that indicates higher distensibility of the skin. However, tretinoin treatment did not significantly affect the density of collagen fibers, elastic fibers, or versican., Conclusion: Topical tretinoin treatment alters the mechanical behavior of post-burn scarred skin by improving its distensibility and thus leads to improved quality of life for patients.

Introduction: Pressure monitoring is crucial for effective pressure therapy. Precise and reliable interface pressure measurement system, however, remains unavailable in current practice., Methodology: This is a validation study on the application of a recently developed device, the Pliance X System, for static interface pressure measurement. Sensor properties were evaluated through series of laboratory tests in the first phase of the study. Phase II was a clinical study using the Pliance X system to differentiate the loading generated on the patients' scars through additional inserts and pressure garment., Results: Results showed high test-retest and inter-rater reliability (ICC > or = 0.995) with good linearity (adjusted R-square=0.997) by measuring standard weights. The maximum deviation between the measurement generated by the sensor and the sphygmomanometer cuff was +/-1.451 mmHg. Results in the clinical trial revealed its discriminant ability in distinguishing different levels of pressure loading on patients with scars (p<0.01)., Conclusion: The commercially available pressure measurement system was found to be a reliable tool for measurement of low interface pressure under static condition.

Anterior chest burns in young females frequently result in complicated problems such as scar contracture, damage to the nipple-areolar complex and breast tissue. Furthermore, an absent breast mound, hypoplasia or disfigurement of developed breasts can result in breast asymmetry and psychological problems. So we presented an alternative procedure that combines burn scar reconstruction and augmentation mammaplasty performed during one operative session. We believe patients who have either smaller natural breasts or burned breast with anterior chest scar contracture can earn both functional and aesthetic benefits via this simultaneous operation.

Following injury, fibroblasts migrate into wounds and differentiate into alpha smooth muscle cell actin (SMCA)-positive cells, termed myofibroblasts, that assemble and remodel the scar. Cultured myofibroblasts assemble larger focal adhesions than do normal dermal fibroblasts and these focal adhesions attach to alpha SMCA-rich stress fibers. Following severe traumatic or thermal injury to the dermis, hypertrophic scars (HTSs) often develop and these scar fibroblasts (HTSFs) express alpha SMCA persistently. We now report that HTSFs stably display large focal adhesions as a consequence of both the autocrine production and activation of transforming growth factor beta1 (TGF-beta1). We also observe that myofibroblasts elaborating larger focal adhesions adhere more tightly to fibronectin. Conditioned medium from HTSFs induces focal adhesion growth in normal fibroblasts and this is blocked by pre-incubation with a soluble TGF-beta1 receptor mimetic. Human foreskin fibroblasts transduced with a retrovirus encoding active TGF-beta1 elaborate large focal adhesions, whereas fibroblasts overexpressing normal, latent TGF-beta1 do not. We conclude that the large focal adhesions found in pathogenic myofibroblasts arise through an autocrine loop involving the production and activation of TGF-beta1; these adhesions likely mediate both tighter adhesion to wound matrix and the exuberant wound contraction observed in pathogenic scars.

Unlabelled: Laser Doppler perfusion imaging (LDI) is an established technique for early assessment of burn depth to help determine a course of treatment. Laser speckle perfusion imaging (LSPI) is an alternative laser based, non-invasive perfusion monitoring technique that offers rapid and high resolution images of tissue. We have evaluated the ability of the LSPI instrument in determining and monitoring burn scar perfusion over time and compared it with the LDI instrument as a standard., Methods: Ten patients with hypertrophic burn scars (time since injury: 1-8 months) were recruited. Burn scars were scanned with both instruments (LSPI and LDI) monthly over a period of 11 months. Clinical grading of the burn scars was assessed on every scan date using the Vancouver burn scar scale., Results: Comparison of the perfusion values determined by each instrument shows a strong positive correlation, r2=0.86 (n=63). Each instrument's output also correlated significantly with the clinical grading of the scar, indicating the expected decrease in perfusion as the clinical condition of the scars improved with time., Significance: The new LSPI instrument compared favorably with the established LDI instrument, yielding similar results. The considerably faster scan time and higher resolution of the LSPI method provides a distinct clinical advantage, both in terms of patient comfort and for reliably matching perfusion characteristics to their associated anatomical features. The fast temporal response of the LSPI instrument could be used to monitor near real-time responses to mechanical or pharmacological interventions to study dynamic vascular changes to burn damaged tissues.

The pathogenesis and progression of wound-healing involve intricate pathways and numerous chemical mediators. This remains an area of intense study as undesirable results of this process, such as hypertrophic scars and keloids, can result in significant morbidity. These lesions are distinct in their characteristics, although they are similar in their distribution in patients with darker skin colors. There is a robust inflammatory mechanism behind the formation of hypertrophic scars and keloids. Furthermore, their development may be intimately related to vitamin D-3, which has been shown to be a powerful anti-inflammatory agent. This chemical is made in the skin, whose production is influenced by various factors of which the amount of melanin is a crucial one. More specifically, an increase in pigmentation has been shown to decrease the amount of vitamin D-3 synthesis in the skin. Thus, this paper proposes the hypothesis linking the propensity of inflammation and subsequent scarring in darker-skinned individuals to the reduced levels of vitamin D-3 production in their skin.

Unlabelled: Various methods are available for evaluating the elasticity of scars. However, the reliability and validity of these methods have been sparsely examined. The aim of this study was to examine the reliability of the subjective evaluation of scar pliability, while at the same time testing the reliability of the measurements of a non-invasive suction device (Cutometer Skin Elasticity Meter 575) on scars. Four observers assessed 49 scar areas of 20 patients with a subjective assessment of pliability. Subsequently, each observer measured the scar areas with the Cutometer. The intraclass correlation coefficients (ICC) of the elasticity (Ue) and extension (Uf) parameters of the Cutometer were acceptable (r = 0.76 and 0.74, respectively) when a single observer carried out the measurements. The subjective assessment of pliability needs to be completed by two or more observers to make the evaluation reliable (r = 0.79). The concurrent validities between the subjective pliability-assessment and each of the Cutometer parameters were statistically significant and ranged from r = 0.29-0.53. The correlations between each of the Cutometer parameters were high and statistically significant (r > or = 0.71)., Conclusion: A single observer can reliably use the Cutometer for the elasticity measurements of scars. Furthermore, either Ue or Uf, instead of all five elasticity values provided by the Cutometer, can be adequately used for the elasticity measurements of scars. The subjective assessment of pliability of scars can only be assessed reliably when completed by two or more observers. The concurrent validity showed that all Cutometer parameters, except for visco-elasticity (Uv), and the subjective assessment of pliability measured the same characteristic of a scar.

Today, wound management to avoid excessive scar formation is increasingly important, especially in populations with Fitzpatrick 3 or higher skin pigmentation. Medical science and industrial development are devoting more effort toward understanding and offering better therapy to control scars. However, advances in scar management have been hampered by the confusing or ambiguous terminology. There is no consensus on what amount of post-traumatic skin scar formation is "normal" and what should be considered "hypertrophic". In the World Health Organization's ICD-9, there is no diagnostic code for hypertrophic scar--only keloid is listed. Yet, the medical and scientific literature distinguishes them as different conditions. Our experience suggests that the diagnosis of keloid disease is greatly over-rendered. For black patients, an elevated scar seems, by default, diagnosed as keloid by most. This confusion results in inappropriate management of scar formation, and occasionally contributes to decision making related to elective or cosmetic surgery. Given that patients are expecting better outcomes from wound care today than in the past, this review article attempts to capture the essential biological factors related to wound scar production and discusses treatment options and indications used by the authors.

Unlabelled: Laser Doppler perfusion imaging (LDI) is a useful tool for the early clinical assessment of burn depth and prognostic evaluation of injuries that may require skin grafting. We have evaluated two commercially available laser Doppler imagers for the perfusion measurement of normal and burn scar tissue., Methods: A single wavelength (635 nm), step-wise scanning LDI and a dual wavelength (633 and 780 nm), continuous scanning LDI were used. Twenty patients with hypertrophic burn scars (time since injury: 1 month-8 years) were recruited and the color and elevation of the scar was clinically assessed using a modified Vancouver Burn Scar Scale. Perfusion of each scar region was measured using both imagers. A symmetric contralateral region of unburned skin was also imaged to record baseline perfusion., Results: Comparisons of wavelength and scanning technique were made using perfusion values obtained from 22 burn scars. Highly significant positive correlation was observed in all comparisons. In addition, output from both instruments was strongly and significantly correlated with the clinical grading of the scar., Significance: Both LDI scanners perform similar perfusion measurements. The results also indicate that red and near-infrared (NIR) wavelength photons provide similar blood flow information. The faster, continuous scanning method provides a clinical advantage without a significant loss of blood flow information. However, a critical evaluation of both instruments suggests that caution must be exercised when using these optical diagnostic techniques and that some knowledge of light-tissue interaction is required for the proper analysis and interpretation of clinical data.

Both transepidermal water loss (TEWL) and skin surface high-frequency conductance are functions of the skin barrier. Systemic sclerosis (SSc) and hypertrophic scar (HS)/keloid are characterized by abnormal fibrotic changes in the dermis. Since the close interrelationship between the epidermis and the dermis has been well established, we analyzed the stratum corneum functions of forearm skin in 39 SSc patients after assessing the degree of the skin thickening and compared those functions with 10 age-matched normal controls. We also analyzed the stratum corneum functions of HS or keloid lesions in seven patients using the same methods, and compared those functions to adjacent or contralateral normal skin in identical patients. Neither the TEWL, nor high-frequency conductance of forearm skin in SSc patients were significantly different from those in normal controls. There was no correlation between the levels of TEWL or high-frequency conductance and the degree of skin thickening in SSc. In HS or keloid conditions, high-frequency conductance was significantly elevated (42.5+/-8.9 vs. 26.4+/-5.7, P<0.001). Although TEWL was elevated, there was no statistical significance (48.6+/-39.7 vs. 25.1+/-10.1). Our results revealed that stratum corneum functions are distinct between SSc and HS or keloid. This may reflect the various natures of dermal changes, which in turn differentiate the functions of the stratum corneum in the diseases.

Unlabelled: Increasing data suggest that the skin nerve system is involved in wound healing. The objective of this study was to investigate the outgrowth of nerve fibers during the burn wound remodeling process and to analyze possible differences between normotrophic and hypertrophic burn wounds. In a prospective study, biopsies were taken from 22 patients with spontaneously healed partial-thickness burns at 1, 4 and 7-month post-burn. Nerve outgrowth and the expression of the neuropeptides substance P, neurokinin A, calcitonin gene-related peptide, vasoactive intestinal peptide and neuropeptide Y was monitored using immunohistochemistry. Our results showed that the number of nerve fibers gradually increased in both the dermis and the epidermis, but that they did not reach the levels of expression present in matched unburned skin of the same patient. A significantly higher number of nerve fibers were observed in normotrophic scars compared with hypertrophic scars. The number of neuropeptides-containing nerves in normotrophic and hypertrophic scars were similar., In Conclusion: 7 months after wound closure, burn wound scars contain less nerve fibers than unburned skin. The significantly higher number of nerve fibers in normotrophic, compared with hypertrophic scars suggests a regulatory role for the skin nerve system in the outcome of burn wound healing.

Blood-flow measurements of microcirculation were used as a quantitative indicator for scar assessment and healing. A laser doppler flowmeter (LDF), giving an integrated instantaneous flux value through a measured volume of skin, was used for the measurements. It has been postulated that the degree of hypertrophy after thermal injury correlates with the degree of microvascular regeneration. This study looked quantitatively at microcirculation in normal and scarred skin of different clinical grading and investigated the comparative responses to changes in local temperature stimuli. An attempt is made to define microcirculation using the parameters of Vasodilation Index (Dli) and Vasomotion Intensity (% Vsm) as respective responses to a rise in local temperature of the skin from 36 degrees C to 44 degrees C. The improvements in both Dli and % Vsm with healing of scar relate to the degree of microvascular regeneration, which in turn correlates with the clinical assessment.

The non-linear viscoelastic properties of skin tissue were characterized by modulus of elasticity E, which represents stiffness, and percentage extension (strain, xi) at load intensities of 20, 40 and 100 gm. The latter property is a measure of the extensibility for both normal skin and hypertrophic scar. A quasi-static extensometer applies a standard rate of extension to the skin and its mechanical properties were obtained from 15 Chinese patients with burn injuries of superficial to full skin thickness burns. Clinical evaluation of hypertrophic scar is qualitative and depends on colour, thickness and hardness or firmness. Using mechanical properties assists in the characterization by providing a quantitative indicator. Higher scar grading is synonymous with increased stiffness and decreased extensibility. Correlation with clinical assessment was achieved with these in vivo viscoelastic properties.

The alteration of normal dermal fibroblast function that leads to the development of hypertrophic scar after thermal injury is unknown. To determine functional differences that might explain this process, fibroblasts were cultured from biopsies of post-thermal injury mature hypertrophic scars and patient-matched normal skin. The mitogenic responses of scar cells to fetal bovine serum, epidermal growth factor (EGF), platelet-derived growth factor (PDGF), and tumor necrosis factor alpha (TNF alpha) were determined and compared to normal skin cells. Collagen synthetic rate was also compared in the presence and absence of transforming growth factor beta 1 (TGF beta 1). Whereas both scar and normal cells responded with increased thymidine uptake to serum and cytokines, the stimulation to EGF and serum was significantly lower in scar cells. In contrast, synthesis of collagen, but not of non-collagenous proteins, was increased in scar relative to normal cells, both basally and when stimulated with low doses of TGF beta 1. Additionally, the fraction of protein synthesized as collagen was significantly higher in scar fibroblasts. These results suggest that fibroblasts from hypertrophic scars demonstrate stable phenotypic differences in cytokine responsiveness in comparison to cells from unaffected skin. The increased rate of collagen synthesis and decreased responsiveness to mitogens are consistent with the increased extracellular matrix content and decreased cellularity of hypertrophic scars.