In a clinimetric analysis, 3D stereophotogrammetry was found to be reliable and valid for measuring scar volume in clinical research.

OBJECTIVES: Volume is an important feature in the evaluation of hypertrophic scars and keloids. Three-dimensional (3D) stereophotogrammetry is a noninvasive technique for the measurement of scar volume. This study evaluated the reliability and validity of 3D stereophotogrammetry for measuring scar volume. STUDY DESIGN AND SETTING: To evaluate reliability, 51 scars were photographed by two observers. Interobserver reliability was assessed by the intraclass correlation coefficient (ICC), and the measurement error was expressed as limits of agreement (LoA). To assess validity, 60 simulated (clay) scars were measured by 3D stereophotogrammetry and subsequently weighed (gold standard). The correlation of volumes obtained by both measures was calculated by a concordance correlation coefficient (CCC), and the measurement error was expressed as a 95% prediction interval. RESULTS: The ICC was 0.99, corresponding to a high correlation of measurements between two observers, although the LoA were relatively wide. The correlation between 3D stereophotogrammetry and the gold standard was also high, with a CCC of 0.97. Again, the plot of the differences and LoA showed moderate agreement for the validity. CONCLUSION: Three-dimensional stereophotogrammetry is suitable for the use in clinical research but not for the follow-up of the individual patient.

Intralesional cryotherapy for treatment of keloid scars: a prospective study.

BACKGROUND: Intralesional cryotherapy is a novel treatment for keloid scars in which the scar is frozen from inside. Published results are promising, but the treatment has only been tested in a Caucasian patient population. Therefore, the authors evaluated intralesional cryotherapy in a patient population including different Fitzpatrick skin types (I through VI). METHODS: This prospective multicenter study with a 1-year follow-up included 27 patients with 29 keloid scars. Intralesional cryotherapy was administered with a disposable liquid nitrogen-based device called CryoShape. Scar assessment was performed using the Patient and Observer Scar Assessment Scale and four objective devices to determine scar color, scar elasticity, scar volume, and patient skin type. RESULTS: Keloid scars showed an average volume decrease of 63 percent (range, 16 to 100 percent) after 12 months, compared with baseline (p < 0.01). Recurrence was seen in seven keloids (24 percent) and hypopigmentation recovered in 69 percent of all keloid scars within 12 months. Scar assessment with the Patient and Observer Scar Assessment Scale showed an overall improvement according to both doctors and patients. In addition, complaints of pain and itching were reduced. When analyzing the results per Fitzpatrick skin type, African American patients showed a higher incidence of persistent hypopigmentation (p = 0.02). CONCLUSIONS: Intralesional cryotherapy for the treatment of keloid scars shows favorable results in terms of reduction of volume and complaints of pain and pruritus. However, no complete eradication was obtained in some cases and recurring scars were seen. In addition, persistent hypopigmentation proved a problem in non-Caucasian patients. CLINICAL QUESTION/LEVEL OF EVIDENCE: Therapeutic, IV.

The hand held Doppler device for the detection of perforators in reconstructive surgery: what you hear is not always what you get.

BACKGROUND: Perforator-based flaps have become indispensable in the treatment of burn scars. Pre-operative perforator mapping is often performed by use of the hand held Doppler device, partly due to its convenience and the low costs. We expected to find sufficient evidence in literature to support the use of the device, however available literature showed a distinct lack of clinimetric studies that adequately tested the reliability. METHODS: To assess reliability, perforator locations were mapped independently by two clinicians using an 8MHz Doppler device. In healthy volunteers the elbow region or the peri-umbilical region were randomly chosen to be the measurement areas of predefined squares (7cm×7cm). Subsequently, the perforators within the area were mapped with Duplex to establish the validity by means of the positive predictive value. RESULTS: 20 volunteers were included. The hand held Doppler technique showed moderate reliability with a mean Dice coefficient of 0.56. Also, poor validity was found expressed by a mean positive predictive value of 55%. CONCLUSIONS: Surprisingly, this study has shown that performance of the hand held Doppler device was moderate. The Doppler should not be used alone for the detection of perforators.

Skin stretching for primary closure of acute burn wounds.

BACKGROUND: In burn care, a well-acknowledged problem is the suboptimal scar outcome from skin grafted burn wounds. With the aim of improving this, we focused on a new technique: excision of the burn wound followed by primary closure, thereby using a skin-stretching device to stretch the adjacent healthy skin. The short- and long-term effect of Skin Stretch was compared to split skin grafting (SSG) in a randomized controlled trial. METHODS: Patients with burn wounds were randomized for SSG or primary wound closure using Skin Stretch. Follow-up was performed at 3 and 12 months postoperatively. The scar surface area was calculated and the scar quality was assessed, using subjective and objective measurement methods. RESULTS: No significant differences between the SSG and the Skin Stretch group were found for scar surface area. In the Skin Stretch group, a significant reduction of the surface area from 65.4cm(2) (13.6-129.1) to 13.4cm(2) (3.0-36.6) was found at 3 months (p=0.028) and at 12 months postoperatively (65.4cm(2) (13.6-129.1) to 33.0cm(2) (8.9-63.7), p=0.046, Wilcoxon signed ranks test). CONCLUSIONS: Skin Stretch for primary closure of acute burn wounds is a suitable technique and can be considered for specific circumscript full-thickness burn wounds. However, future research should be performed to provide additional scientific evidence.

Differential item functioning in the Observer Scale of the POSAS for different scar types.

PURPOSE: To investigate whether the Observer Scale of the Patient and Observer Scar Assessment Scale (POSAS) can serve as a generic measure for scar quality across different scar types. METHODS: A collection of POSAS scores derived from several clinical trials on burn (n = 404), linear (n = 384), and keloidal scars (n = 282) was analyzed using the partial credit model of the Rasch analysis package RUMM2030. RESULTS: Differential item functioning (DIF) was observed for the Observer Scale of the POSAS between the three scar types for the items pliability, thickness, and surface area, which could be solved by item splitting. The items pigmentation and thickness showed disordered thresholds, considerable misfit, and unpredictability. CONCLUSION: Users of the Observer Scale of the POSAS must be aware that the raw scores obtained from burn, linear, and keloidal scars cannot be compared without the scar-specific DIF adjustment of the items pliability, thickness, and surface area.

Three-dimensional digital stereophotogrammetry: a reliable and valid technique for measuring scar surface area.

BACKGROUND: The surface area of scars is an important outcome parameter in scar assessment. It is often used to quantify the extent of scar features, such as pigmentation disturbances, hypertrophy, and contracture. Currently available techniques for measuring the surface area are known to be cumbersome or do not meet the basic clinimetric criteria (i.e., reliability and validity). Three-dimensional stereophotogrammetry is a technique that may improve the quality of surface area measurements. The aim of this study was to investigate the reliability and validity of three-dimensional stereophotogrammetry for measuring scar surface area. METHODS: In a cross-sectional study, two independent clinicians photographed and measured 50 scar areas of 32 patients using a handheld stereographic camera, to assess reliability. Subsequently, using planimetry, the scar surface was traced on a transparent sheet (considered the accepted standard) to assess validity. RESULTS: Three-dimensional stereophotogrammetry showed good reliability, with an intraclass correlation coefficient of 0.99 and a coefficient of variation of 6.8 percent. To visualize the differences between the two observers, data were plotted and the limits of agreement were calculated at 0 ± 0.19 × mean surface area. Also, excellent validity was found, with a concordance correlation coefficient of 0.99. CONCLUSION: This study showed that three-dimensional stereophotogrammetry is a reliable and valid tool for research purposes in the field of scar surface area measurements. CLINICAL QUESTION/LEVEL OF EVIDENCE: Diagnostic, I.

Clinical effectiveness of dermal substitution in burns by topical negative pressure: a multicenter randomized controlled trial.

Previous research has shown clinical effectiveness of dermal substitution; however, in burn wounds, only limited effect has been shown. A problem in burn wounds is the reduced take of the autograft, when the substitute and graft are applied in one procedure. Recently, application of topical negative pressure (TNP) was shown to improve graft take. The aim of this study was to investigate if application of a dermal substitute in combination with TNP improves scar quality after burns. In a four-armed multicenter randomized controlled trial, a split-skin graft with or without a dermal substitute and with or without TNP was compared in patients with deep dermal or full-thickness burns requiring skin transplantation. Graft take and rate of wound epithelialization were evaluated. Three and 12 months postoperatively, scar parameters were measured. The results of 86 patients showed that graft take and epithelialization did not reveal significant differences. Significantly fewer wounds in the TNP group showed postoperative contamination, compared to other groups. Highest elasticity was measured in scars treated with the substitute and TNP, which was significantly better compared to scars treated with the substitute alone. Concluding, this randomized controlled trial shows the effectiveness of dermal substitution combined with TNP in burns, based on extensive wound and scar measurements.

Outcome after burns: an observational study on burn scar maturation and predictors for severe scarring.

Long-term outcome of burn scars as well as the relation with clinically relevant parameters has not been studied quantitatively. Therefore, we conducted a detailed analysis on the clinical changes of burn scars in a longitudinal setup. In addition, we focused on the differences in scar quality in relation to the depth, etiology of the burn wound and age of the patient. Burn scars of 474 patients were subjected to a scar assessment protocol 3, 6, and 12 months postburn. Three different age groups were defined (≤5, 5-18, and ≥18 years). The observer part of the patient and observer scar assessment scale revealed a significant (p < 0.001) improvement in scar quality at 12 months compared with the 3- and 6-month data. Predictors for severe scarring are depth of the wound (p < 0.001) and total body surface area burned (p < 0.001). Etiology (p = 0.753) and age (p > 0.230) have no significant influence on scar quality when corrected for sex, total body surface area burned, time, and age or etiology, respectively.

Rasch analysis of the Patient and Observer Scar Assessment Scale (POSAS) in burn scars.

PURPOSE: The Patient and Observer Scar Assessment Scale (POSAS) is a questionnaire that was developed to assess scar quality. It consists of two separate six-item scales (Observer Scale and Patient Scale), both of which are scored on a 10-point rating scale. After many years of experience with this scale in burn scar assessment, it is appropriate to examine its psychometric properties using Rasch analysis. METHODS: Cross-sectional data collection from seven clinical trials resulted in a data set of 1,629 observer scores and 1,427 patient scores of burn scars. We examined the person-item map, item fit statistics, reliability, response category ordering, and dimensionality of the POSAS. RESULTS: The POSAS showed an adequate fit to the Rasch model, except for the item surface area. Person reliability of the Observer Scale and Patient Scale was 0.82 and 0.77, respectively. Dimensionality analysis revealed that the unexplained variance by the first contrast of both scales was 1.7 units. Spearman correlation between the Observer Scale Rasch measure and the overall opinion of the clinician was 0.75. CONCLUSION: The Rasch model demonstrated that the POSAS is a reliable and valid scale that measures the single-construct scar quality.

Sustainable effect of skin stretching for burn scar excision: long-term results of a multicenter randomized controlled trial.

PURPOSE: Primary wound closure of large defects after burn scar excision may be facilitated by intraoperative stretching of the adjacent skin. In a randomized controlled trial (RCT), the effect of skin stretching for wound closure after scar excision (SS) was compared to scar excision without additional techniques (SE). Short-term results already showed that in the SS group larger scars could be excised in a one-step procedure. In this paper, the long-term scar outcome using reliable and valid measurement tools was evaluated. BASIC PROCEDURES: The percentage of total remaining scar area (i.e. remaining scar compared to preoperative scar), the percentage of linear scarring (i.e. surface area of linear scar compared to excised scar) and scar hypertrophy was measured at 3 and 12 months postoperatively. MAIN FINDINGS: At 12 months postoperatively, the percentage of total remaining scar area was significantly lower in the SS group (26%) compared to the SE group (43%). The percentage of linear scarring (SS: 21%, SE: 25%) and the incidence of hypertrophy (SS: 29%, SE: 40%) were not significantly different between the treatment groups. CONCLUSIONS: This RCT demonstrates the long-term beneficial and sustainable effect skin stretching for wound closure after scar excision without leading to wider linear scars or more scar hypertrophy.

Objective scar assessment tools: a clinimetric appraisal.

BACKGROUND: Scars may lead to an array of cosmetic, psychological, and functional problems. Different scar features can be distinguished (i.e., color, thickness, relief, pliability, and surface area) that are clinically relevant and contribute to the quality and judgment of a scar. Today, objective evaluation of these scar features is indispensable for practicing evidence-based medicine (e.g., to evaluate the outcome of clinical trials). In this review, an overview and update are given on the most relevant noninvasive objective measurement tools for scar evaluation. METHODS: A PubMed literature search was performed. Articles evaluating the clinimetric properties of noninvasive scar assessment tools were included. The selected objective measurement tools were then critically reviewed with respect to the clinimetric properties of reliability, validity, and feasibility. RESULTS: In total, 75 articles were selected and 23 different noninvasive measurement methods were evaluated. CONCLUSION: Based on the scar features color, thickness, relief, pliability, and surface area, the best measurement tools that are currently available were recommended.

A cadaver study of the vascular territories of dominant and nondominant internal mammary artery perforators.

The perfusion territory of the pedicled internal mammary artery perforator flap has been described, but the number of perforators to be included in the flap's pedicle is controversial. We studied the vascular territory of the dominant perforator and the contribution of additional nondominant perforators to it. Therefore, the dominant perforators in 9 fresh cadavers and the nondominant perforators in 4 of these, were injected with water-based ink. The dominant perforator vascularized a territory extending from the superior border of the clavicle to the xiphoid, and from midsternal to the anterior axial fold, with a mean craniocaudal length of 19.4 cm (range, 17.0-24.0) and a mean mediolateral width of 18.6 cm (range, 16.0-22.5). Additional injection of nondominant perforators did not lead to any substantial enlargement of this territory. One single dominant perforator vascularizes a large part of the hemithorax, allowing for various flap designs. Nondominant perforators do not have to be included in the vascular pedicle of the internal mammary artery perforator flap, which leads to less donor-site morbidity.

An objective device for measuring surface roughness of skin and scars.

BACKGROUND: Scar formation remains a major clinical problem; therefore, various therapies have been developed to improve scar quality. To evaluate the effectiveness of these therapies, objective measurement tools are necessary. An appropriate, objective measuring instrument for assessment of surface roughness is not yet available in a clinical setting. The Phaseshift Rapid In Vivo Measurement of the Skin (PRIMOS) (GFMesstechnik GmbH, Teltow, Germany) could be such an instrument. This device noninvasively produces a 3-dimensional image of the skin microtopography and measures surface roughness. OBJECTIVE: The aim of this study was to investigate the reliability and validity of the PRIMOS for objective and quantitative measurement of surface roughness of skin and scars. METHODS: Three observers assessed skin and burn scars in 60 patients using the PRIMOS and a subjective scale, the Patient and Observer Scar Assessment Scale. Reliability was tested using the intraclass correlation of intraobserver and interobserver measurements. An intraclass correlation coefficient of 0.7 or greater was required for reliable results. To test validity, scores of the PRIMOS were compared with scores of the subjective scale (Pearson correlation). A Pearson correlation coefficient greater than 0.6 was considered a strong positive correlation. RESULTS: All 3 surface roughness parameters of the PRIMOS showed good intraobserver and interobserver reliability for skin and scars (intraclass correlation coefficient arithmetic mean of surface roughness > 0.85, mean of 5 highest peaks and 5 deepest valleys from entire measuring field > 0.88, peak count > 0.86). The parameter arithmetic mean of surface roughness showed a strong correlation with the subjective score (Pearson arithmetic mean of surface roughness 0.70; mean of 5 highest peaks and 5 deepest valleys from entire measuring field 0.53; peak count 0.54). LIMITATIONS: The reliability and validity of the PRIMOS were only tested on skin and burn scars, not in other dermatologic diseases. CONCLUSIONS: The PRIMOS is a valid and reliable tool for objective noninvasive evaluation of surface roughness of both skin and burn scars.

Anatomy of the vascular pedicle of the internal mammary artery perforator (IMAP) flap as applied for head and neck reconstruction.

INTRODUCTION: The vascular pedicle of the internal mammary artery perforator (IMAP) flap and its enhancement by inclusion of the internal mammary vessels up to the level of the first rib have not been systematically assessed anatomically, to date. This study assesses these features of this pedicle in light of the flap's application in head and neck reconstruction. MATERIAL AND METHODS: The length of the dominant perforator and the enhanced vascular pedicle of the IMAP flap were measured in 27 fresh cadaveric hemi-thoraxes. RESULTS: In 18 out of 27 cadaveric cases (0.67) the second perforator was dominant. The mean length of the 27 dominant perforators was 47 mm (range: 30-66 mm). By enhancement up to the level of the first rib, the mean length of the vascular pedicle could be doubled to 92 mm when based on the second perforator (0.67). In the five cases (0.19), where the third perforator was dominant, the mean length of the enhanced pedicle was 104 mm, whereas it was 61 mm in the four cases (0.15) where the first perforator was dominant. CONCLUSION: This is the first study that assessed the enhanced length of the vascular pedicle of the IMAP flap. Our results show that the mean length of the dominant second perforator may be doubled by such enhancement and that the arc of rotation to the head and neck region may, then, be doubled again. Hereby, even high-located defects in the head and neck region can be reached. This provides a better understanding of the feasibility of the pedicled IMAP flap in head and neck reconstruction.

Topical silicone gel versus placebo in promoting the maturation of burn scars: a randomized controlled trial.

BACKGROUND: Silicone sheets are widely used in the treatment of hypertrophic scars, although application around joints may cause limited adherence and reduced movement. To approach these problems, a topical silicone gel was developed that can be applied easily in a thin layer, and that is nonrestrictive and less apparent. The objective of this study was to investigate the effectiveness of topical silicone gel in promoting the maturation of burn scars. METHODS: Forty-six scars on 23 patients were included in a randomized, placebo-controlled, within-subject comparative, double-blinded, clinical trial and followed for 1 year. The mean age of the scars at inclusion was 4 months. Effectiveness on scar quality was evaluated using the Patient and Observer Scar Assessment Scale and the DermaSpectrometer. Significance was tested using repeated measures analyses and Wilcoxon paired-sample signed rank tests. RESULTS: Over all visits, the benefit on surface roughness was statistically significant (p = 0.012). At individual time points, the surface of the topical silicone gel-treated scars showed significantly less roughness (p = 0.014) at 3 months after start of the treatment, and the topical silicone gel-treated scars were significantly less itchy (p = 0.018 and p = 0.013, respectively) at 3 and 6 months. CONCLUSION: Topical silicone gel significantly improves the surface roughness of burn scars, and patients experience significantly less itching in the first half year after application.

Biological background of dermal substitutes.

Dermal substitutes are of major importance in treating full thickness skin defects, both in acute and chronic wounds. In this review we will outline specific requirements of three classes of dermal substitutes: Biological and clinical requirements will be translated to composition, physical structure, immunological properties and cell-matrix interactions of the various materials. Important properties like pore size, cell adhesion sites (e.g. RGD sequences), crosslinking, degradability and the presence of a basement membrane will be discussed for each of the different classes of materials.