Basic fibroblast growth factor accelerates and improves second‐degree burn wound healing

Second‐degree burns are sometimes a concern for shortening patient suffering time as well as the therapeutic choice. Thus, adult second‐degree burn patients (average 57.8 ± 13.9 years old), mainly with deep dermal burns, were included. Patients receiving topical basic fibroblast growth factor (bFGF) or no bFGF were compared for clinical scar extent, passive scar hardness and elasticity using a Cutometer, direct scar hardness using a durometer, and moisture analysis of the stratum corneum at 1 year after complete wound healing. There was significantly faster wound healing with bFGF, as early as 2.2 ± 0.9 days from the burn injury, compared with non‐bFGF use (12.0 ± 2.2 vs. 15.0 ± 2.7 days, p<0.01). Clinical evaluation of Vancouver scale scores showed significant differences between bFGF‐treated and non‐bFGF–treated scars (p<0.01). Both maximal scar extension and the ratio of scar retraction to maximal scar extension, elasticity, by Cutometer were significantly greater in bFGF‐treated scars than non‐bFGF–treated scars (0.23 ± 0.10 vs. 0.14 ± 0.06 mm, 0.59 ± 0.20 vs. 0.49 ± 0.15 mm: scar extension, scar elasticity, bFGF vs. non‐bFGF, p<0.01). The durometer reading was significantly lower in bFGF‐treated scars than in non‐bFGF–treated scars (16.2 ± 3.8 vs. 29.3 ± 5.1, p<0.01). Transepidermal water loss, water content, and corneal thickness were significantly less in bFGF‐treated than in non‐bFGF–treated scars (p<0.01).     

The evaluation of a clinical scar scale for porcine burn scars

This study describes the evaluation of a clinical scar scale for our porcine burn scars, which includes scar cosmetic outcome, colour, height and hair, supplemented with reference porcine scar photographs representing each scar outcome and scar colour scores. A total of 72 porcine burn scars at week 6 after burn were rated in vivo and/or on photographs. Good agreements were achieved for both intra-rater reliability (correlation is 0.86–0.98) and inter-rater reliability (ICC = 80–85%). The results showed statistically significant correlations for each pair in this clinical scar scale (p < 0.01), with the best correlation found between scar cosmetic outcome and scar colour. A multivariate principle components analysis revealed that this clinical scar assessment was highly correlated with scar histology, wound size, and re-epithelialisation data (p < 0.001). More severe scars are clinically characterised by darker purple colouration, more elevation, no presence of hair, histologically by thicker scar tissue, thinner remaining normal dermis, are more likely to have worse contraction, and slower re-epithelialisation. This study demonstrates that our clinical scar scale is a reliable, independent and valuable tool for assessing porcine burn outcome and truthfully reflects scar appearance and function. To our knowledge, this is the first study demonstrating a high correlation between clinical scar assessment and scar histology, wound contraction and re-epithelialisation data on porcine burn scars. We believe that the successful use of porcine scar scales is invaluable for assessing potential human burn treatments.     

The correlation of in vivo burn scar contraction with the level of α-smooth muscle actin expression

This study describes the direct association of in vivo burn scar contraction with the level of α-smooth muscle actin (α-SMA) in scar tissue, in a porcine burn model. The expression of α-SMA was investigated in 100 biopsies from 44 6-week old burn scars and in 85 biopsies from 16 2-week old burn wounds. Statistical analysis showed that the levels of α-SMA in 6-week old scars were significantly negatively correlated to scar size (r = −0.68) and the higher levels of α-SMA were observed in smaller scars. Moreover, α-SMA was also found to be significantly positively correlated to re-epithelialisation time (r = 0.57) and scar thickness (r = 0.58) and higher levels of α-SMA were detected in thicker scars with delayed wound closure. Further statistical analysis revealed that scar contraction can be explained best by the level of α-SMA expression and partially by scar thickness. Other variables, such as different dressings and individual pig, may also partly contribute to scar contraction. At week 2 after-burn, the level of α-SMA expression in 16 burn wounds was significantly related to the depth of burns and wound healing outcome. To our knowledge, this is the first study to provide in vivo evidence of the association of α-SMA expression with scar contraction, scar thickness, re-epithelialisation time and the depth of burn in a large animal burn model with scars similar to human hypertrophic scar.     

Preference for donor site scar orientation in pedicled latissimus dorsi breast reconstruction

A survey was carried out to ascertain the preference for donor site scar orientation in patients undergoing pedicled latissimus dorsi breast reconstruction and their views on breast reconstruction in general. One hundred twelve women (59 Chinese, 53 Western) completed the questionnaire. Participants were asked to state their preferred scar orientation (i.e., oblique, horizontal, or vertical) based on photographs showing the position of the scars. Demographic information and views on issues surrounding breast reconstruction in general were also collected. Data was analyzed non-parametrically with chi-square test and t test. The mean age of participants was 39.5 years (20–73 years). Seventy-seven percent of the participants would opt for an immediate breast reconstruction if offered (p < 0.001). Eighty-six percent would have objection to the use of silicone implant as a whole or part of a reconstruction (p < 0.001). Vertical and horizontal scars were the preferred orientation, with no women choosing the oblique orientation as their first choice (p < 0.001). The non-Chinese of 40 years or older, as well as Chinese women from all age groups, preferred the horizontal scar (p < 0.05). We demonstrated that both culture and age impact on the preferred scar orientation in breast reconstruction. Women in the age group we commonly reconstruct favored the horizontal scar. However, the younger women of non-Chinese origin tended to favor the vertical scar.     

Crosstalk among adipose tissue,vitamin D level,and biomechanical properties of hypertrophic burn scars

PurposeThis 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.MethodsA 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.ResultsBurn 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).ConclusionAdipose 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.     

Early postoperative treatment of thyroidectomy scars using botulinum toxin: A split‐scar,double‐blind randomized controlled trial

Operational scars, especially those located on the exposed parts of the body, can be distressing. Despite high demand for an early intervention to minimize surgical scars, there is yet no universal consensus on optimal treatment. A split‐scar, double‐blind randomized controlled trial was held to assess the safety and efficacy of early postoperative botulinum toxin type A (BTA) injection in surgical scars. A single session of treatment was performed where BTA was allocated to one half of the scar and 0.9% saline to the control half. Scars were assessed using the modified Stony Brook Scar Evaluation Scale (SBSES) with standardized photographs. Fifteen patients completed the study, and their data were analyzed. At 6 months' follow‐up, a significant improvement in SBSES score was noted for the BTA‐treated halves of the scars (p < 0.001), with minimal change on the saline‐treated side (p = 0.785). The mean calculated difference in SBSES scores (final/initial) between the BTA‐treated side and the saline‐treated side was also significant (p < 0.001). Early postoperative BTA injection was safe and effective in modulating thyroidectomy scars and may be a promising option for scar prevention.     

Validation of the burn intervention score in a National Burn Centre

The Linköping burn score has been used for two decades to calculate the cost to the hospital of each burned patient. Our aim was to validate the Burn Score in a dedicated Burn Centre by analysing the associations with burn-specific factors: percentage of total body surface area burned (TBSA%), cause of injury, patients referred from other (non-specialist) centres, and survival, to find out which of these factors resulted in higher scores. Our second aim was to analyse the variation in scores of each category of care (surveillance, respiration, circulation, wound care, mobilisation, laboratory tests, infusions, and operation).We made a retrospective analysis of all burned patients admitted during the period 2000–15. Multivariable regression models were used to analyse predictive factors for an increased daily burn score, the cumulative burn score (the sum of the daily burn scores for each patient) and the total burn score (total sum of burn scores for the whole group throughout the study period) in addition to sub-analysis of the different categories of care that make up the burn score.We retrieved 22 301 daily recordings for inpatients. Mobilisation and care of the wound accounted for more than half of the total burn score during the study. Increased TBSA% and age over 45 years were associated with increased cumulative (model R² 0.43, p < 0.001) and daily (model R² 0.61, p < 0.001) burn scores. Patients who died had higher daily burn scores, while the cumulative burn score decreased with shorter duration of hospital stay (p < 0.001).To our knowledge this is the first long term analysis and validation of a system for scoring burn interventions in patients with burns that explores its association with the factors important for outcome. Calculations of costs are based on the score, and it provides an indicator of the nurses’ workload. It also gives important information about the different dimensions of the care provided from thorough investigation of the scores for each category.     

Patient-reported scar quality of donor-sites following split-skin grafting in burn patients: Long-term results of a prospective cohort study

BackgroundSkin grafting is the current gold standard for treatment of deeper burns. How patients appraise the donor-site scar is poorly investigated. The aim of this study was to evaluate long-term patient-reported quality of donor-site scars after split skin grafting and identify possible predictors.MethodsA prospective cohort study was conducted. Patients were included in a Dutch burn centre during one year. Patient-reported quality of donor-site scars and their worst burn scar was assessed at 12 months using the Patient and Observer Scar Assessment Scale (POSAS). Mixed model analyses were used to identify predictors of scar quality.ResultsThis study included 115 donor-site scars of 72 patients with a mean TBSA burned of 11.2%. The vast majority of the donor-site scars (84.4%) were rated as having at least minor differences with normal skin (POSAS item score ≥2) on one or more scar characteristics and the overall opinion on 80.9% of the donor-site scars was that they deviated from normal skin 12 months after surgery. The overall opinion on the donor-site scar was 3.2 ± 2.1 vs. 5.1 ± 2.4 on the burn scar. A younger age, female gender, a darker skin type, and location on the lower leg were predictors of reduced donor-site scar quality. In addition, time to re-epithelization was associated with scar quality.ConclusionThis study provided new insights in long-term scar quality of donor-sites. Donor-site scars differed from normal skin in a large part of the population 12 months after surgery. Results of this study can be used to inform patients on the long-term outcomes of their scars and to tailor preventive or therapeutic treatment options.     

Children's post-burn scars in Mongolia

This study aimed to identify some risk factors for post-burn scarring in children aged 0–18 years. One hundred and eighty two participants were involved in this cohort study. Under the age of 18 who were admitted to the Department of Burn Reconstructive Surgery with a diagnosis of upper and lower extremity burns were followed for 6 months. A total of 182 participants (62.1% male, and 37.9% female participants) enrolled in this study. Age ranged from 1 to 17 and the average age was 3.95 ± 3.35. The degree of burn and the anatomical location of the burn had a statistically significant effect on the development of hypertrophic scars. The length of the patient's hospitalisation days and the area of ​​the burn were statistically correlated with wound healing (P = 000, P = .074). For example, the average length of hospitalisation days was 8 ± 5 days in the hypertrophic scars group of patients, and in the group with normal scars, average bed days were 6 ± 3 days (P = .000). Grade IIIb burns increased the risk of hypertrophic scar development by 4.9 times and grade IV burns increased it by 2.5 times. In addition, when the area of burns was 11% or more, the risk of hypertrophic scar development was increased by 58.8%. In the case of wound swab infection, the risk of hypertrophic scar development was 12.4% higher (B = 1.124, 95 EI = 0.55; 2.28, P = .748). Participants' age, burn area and degree of burn are statistically significant risk factors for post-burn scarring in children aged 0–18 years.     

Flaminal® versus Flamazine® in the treatment of partial thickness burns: A randomized controlled trial on clinical effectiveness and scar quality (FLAM study)

Although partial thickness burns are the most frequently reported burn injuries, there is no consensus on the optimal treatment. The objective of this study was to compare the clinical effectiveness and scar quality of Flaminal® Forte to silver sulfadiazine (Flamazine®) in the treatment of partial thickness burns. In this two‐arm open label multicenter randomized controlled trial, adult patients with acute partial thickness burns and an affected total body surface area of less than 30% were randomized between Flaminal® Forte and Flamazine® and followed for 12 months. Dressing changes in the Flamazine® group were performed daily, and in the Flaminal® group during the first 3 days post burn and thereafter every other day until complete wound healing or surgery. Forty‐one patients were randomly allocated to Flaminal® Forte and 48 patients to Flamazine®. The primary outcome was time to wound healing, which did not differ between the groups: median 18 days with Flaminal® Forte (range 8–49 days) versus 16 days with Flamazine® (range 7–48 days; p = 0.24). Regarding the secondary outcomes during hospital admission, there were no statistically significant differences between the groups concerning need for surgery, pain scores, pruritus, or pain‐related and anticipatory anxiety. More patients in the Flaminal® group developed wound colonization (78% versus 32%, p < 0.001), but the treatment groups did not differ regarding the incidence of local infections and use of systemic antibiotics. In terms of scar quality, no statistically significant differences between both treatment groups were found regarding subjective scar assessment (Patient and Observer Scar Assessment Scale (POSAS)), scar melanin and pigmentation (DermaSpectrometer®), and scar elasticity and maximal extension (Cutometer®) during 12 month postburn. In conclusion, time to wound healing did not differ, but the use of Flaminal® Forte seemed favorable because less dressing changes are needed which lowers the burden of wound care.     

In vitro burn model illustrating heat conduction patterns using compressed thermal papers

To date, heat conduction from heat sources to tissue has been estimated by complex mathematical modeling. In the present study, we developed an intuitive in vitro skin burn model that illustrates heat conduction patterns inside the skin. This was composed of tightly compressed thermal papers with compression frames. Heat flow through the model left a trace by changing the color of thermal papers. These were digitized and three‐dimensionally reconstituted to reproduce the heat conduction patterns in the skin. For standardization, we validated K91HG‐CE thermal paper using a printout test and bivariate correlation analysis. We measured the papers' physical properties and calculated the estimated depth of heat conduction using Fourier's equation. Through contact burns of 5, 10, 15, 20, and 30 seconds on porcine skin and our burn model using a heated brass comb, and comparing the burn wound and heat conduction trace, we validated our model. The heat conduction pattern correlation analysis (intraclass correlation coefficient: 0.846, p < 0.001) and the heat conduction depth correlation analysis (intraclass correlation coefficient: 0.93, p < 0.001) showed statistically significant high correlations between the porcine burn wound and our model. Our model showed good correlation with porcine skin burn injury and replicated its heat conduction patterns.     

Course of scar quality of donor sites following split skin graft harvesting: Comparison between patients and observers

There exists little to no data on the development of donor‐site scars that remain after split skin graft harvesting. The objectives of this study were to (a) examine changes in characteristics of donor‐site scar quality over time and (b) assess the agreement between patient‐reported and observer‐reported donor‐site scar quality in a burn population. A prospective cohort study was conducted including patients who underwent split skin grafting for their burn injury. Patients and observers completed the Patient and Observer Scar Assessment Scale (POSAS) for the first harvested donor site at 3 and 12 months post‐surgery. This study included 80 patients with a median age of 34 years. At 3 months post‐surgery, the patients scored the POSAS items itch and color as most deviant from normal skin, both improved between 3 and 12 months (3.1 vs 1.5 and 5.0 vs 3.5, respectively [P < .001]). Other scar characteristics did not show significant change over time. The patients' overall opinion score improved from 3.9 to 3.2 (P < .001). Observers rated the items vascularization and pigmentation most severe, only vascularization improved significantly between both time points. Their overall opinion score decreased from 2.7 to 2.3 (P < .001). The inter‐observer agreement between patients and observers was considered poor (ICC < 0.4) at both time points. Results of current study indicate that observers underestimate the impact of donor‐site scars. This has to be kept in mind while guiding therapy and expectations. LEVEL OF EVIDENCE: II, prospective cohort study.     

Combination treatment utilizing fractional ablative and continuous wave CO2 lasers for hypertrophic burn scars

BackgroundHypertrophic scars are devastating outcomes of severe burn injuries, producing physical and mental burdens. Adequate treatment is of benefit to relieve these burdens. Laser therapy has shown scar reducing effects. In this study, we compared outcomes after combination of two different lasers or single laser treatment to treat severe hypertrophic burn scars.MethodsForty patients with hypertrophic burn scars were included in one of two therapeutic groups: continuous wave CO₂ laser and fractional ablative CO₂ laser group (group 1, n = 20) or fractional ablative CO₂ laser alone group (group 2, n = 20). Hypertrophic scars were evaluated by the observer-rated Vancouver Scar Scale (VSS) before and after treatment and by patient-completed questionnaires after treatment. Comparative analyses were performed before and after treatment, and time-dependent improvement was also analyzed.ResultsForty patients (54 hypertrophic scars) completed the laser treatment protocols. Group 1 exhibited significantly more improvement in VSS vascularity, pliability, and height indices than group 2 (p < 0.05). Time-dependent analysis of total VSS scores suggested that group 1 experienced more improvement during a shorter treatment period (p < 0.05). For patient-reported outcomes, group 1 noted better grades than group 2 in four indices, namely scar appearance, scar thickness, pain, and pruritus (p < 0.05).ConclusionEffective scar reduction was achieved using combination laser treatment, with significant improvement in multiple observer- and patient-reported outcomes. The shorter treatment period of the combination method can be a merit, as prolonged hypertrophic scars may increase morbidity. Nonetheless, cautious treatment protocols are necessary to avoid undesirable sequelae related to laser application.     

Can prompt treatment of childhood UTI prevent kidney scarring?

The aim of the study reported here was to determine whether kidney scarring after urinary tract infections (UTI) in children can be prevented and to identify the risk factors for developing scars. We identified children in the Northern health region of the UK who had been seen to develop scars, identified as new defects on dimercapto-succinic acid (DMSA) scanning. Risk factors were sought by reviewing case-notes and interviews with parents. Twenty girls were identified whose new scarring was strongly associated with having both vesicoureteric reflux (VUR) and a UTI (p = 0.0001); 19/23 (83%) of kidneys exposed to both of these factors developed scars. Children were much more likely to be febrile (94 vs. 30%, p < 0.0001) or unwell (82 vs. 10%, p < 0.0001) during their earlier UTIs when they were of median age 2.8 years (range 0.3–5.0 years) and did not scar, compared to their later UTIs at age 7.3 years (1.2–12.5 years), when they did scar. However, most patients were treated within 1 day of their symptoms for their early UTIs, compared to a wait ≥7 days for later UTIs (p = 0.001). Being febrile or unwell during a UTI does not predict the development of scars, but prompt treatment appears to prevent scarring in children with VUR.     

Long term sensory function after minor partial thickness burn: A pilot study to determine if recovery is complete or incomplete

BackgroundAcute burn damages skin architecture, including nerve endings, altering sensation and influencing recovery of quality of life and participation. It is established that sensation is reduced in scars after deep burn. However, it is unclear if sensory deficits exist in mild scars. The aim of this trial was to determine if sensory deficits persist in mature scars after minor partial thickness burn.MethodsThis observational pilot involved 30 patients with ‘good quality’ scars (defined as VSS ≤5 at ≥6 months post-burn). Sensory function was compared in scars and site matched uninjured skin using von Frey filaments and two-point discrimination (2-PD). Multivariable regression was used to predict the influence of burn and confounders on sensory outcomes.ResultsBoth pressure and 2-PD distance were significantly greater in scar compared to uninjured sites, indicating reduced sensory function. For von Frey filaments, the median was 3.84 (IQR = 1) in scars and 3.22 (IQR = 1) for uninjured (p = 0.001). For 2-PD, the median was 3.9 cm (IQR = 1.8) for scars and 2.6 cm (IQR = 1.6) for control sites (p = 0.001).ConclusionMeasureable sensory deficits persist in mature, good quality burn scars. These deficits may influence long-term recovery after minor partial thickness burn.     

Comparison of wound closure techniques in median sternotomy scars in children: subcuticular suture versus Steri-Strip™ S

Objectives: The aim of this retrospective study was to compare subcuticular sutures and Steri-Strip? S in closing median sternotomy incisions in children with regard to wound healing and scar formation.

Methods: Fifty-three children and adolescents were enrolled in this study who all underwent a median sternotomy at age 0–18?years and had their presternal cutaneous wounds closed with either a running subcuticular suture (Group 1) or Steri-Strip? S (Group 2). Their scars were assessed using the Patient and Observer Scar Assessment Scale (POSAS). Secondary outcome measures were the scar measurements and the incidence of wound problems post-surgery.

Results: A significant difference was found between both groups in median POSAS observer scale scores for the items thickness (p?=?.027), pliability (p?=?.045), surface area (p?=?.045) and the total score (p?=?.048). All in favor of the subcuticular suture group. There were no significant differences concerning the POSAS patient scale scores. Middle parts of scars of patients in Group 2 were significantly broader (p?=?.001) than scars of patients in Group 1. No significant differences concerning wound problems were found.

Conclusions: There are, according to our results, no significant differences in wound healing of median sternotomy incisions in children closed with either a subcuticular suture or Steri-Strip? S. Significant differences do exist regarding scar formation and final cosmetic results of the scars, in favor of subcuticular closure.     

Risk factors for hypertrophic surgical scar development after thyroidectomy

Postoperative neck scarring is a major concern for patients who undergo thyroid surgery; however, the treatments for hypertrophic scars are generally considered by patients to provide unsatisfactory outcomes. Therefore, risk factors should be identified and prevention of these factors is considered to be critical in management. We reviewed the medical records of 96 thyroidectomy patients who were divided into two groups based on scar type: patients with hypertrophic (n = 61) and linear flat scars (n = 35). Multivariable logistic regression model was developed to identify risk factors for developing hypertrophic scar. There was no significant difference between the two groups in terms of age, gender ratio, tumor type, and type of operation. Multivariable analysis showed that hypertrophic scar development was associated with scars located within 1 cm above the sternal notch (odds ratio [OR] = 5.94, p = 0.01), prominent sternocleidomastoid muscles (OR = 12.03, p < 0.01), and a high body mass index (OR = 1.33, p = 0.01). The area under the receiver operating characteristic curve for risk factors was 0.85. Development of hypertrophic scar after thyroidectomy was found to be associated with specific preoperative factors such as incision site near the sternal notch, prominent sternocleidomastoid muscles, and high body mass index.     

No-Vertical-Scar Technique Versus Inverted T-Scar Technique in Reduction Mammoplasty: A Two-Center Comparative Study

Currently, a reverse T-shaped scar remains in the infraareolar area after most of the frequently used techniques for reduction mammoplasty. A two-center study was performed for an understanding of the effects from the amount of scars on the aesthetic satisfaction of patients. Long-term follow-up results for 24 patients who underwent the McKissock (inverted T-scar) technique (group 1) in a university hospital were compared with the results for 29 patients who underwent a “no-vertical-scar technique” (group 2) at another hospital in terms of aesthetic results. With this aim, a questionnaire was designed to assess the patients’ degree of aesthetic satisfaction with different aspects. Additionally, the most current photos of each patient were evaluated for aesthetic results by four physicians and four medical students. Areola-fold and nipple-notch distances were measured as an objective evaluation. The significance of the results was tested using dependent or independent sample t tests. Notch-nipple and areola-fold distances both were greater in group 2 than in group 1, both preoperatively and postoperatively (p < 0.001). The personal satisfaction questionnaire showed that the group 2 patients rated scar satisfaction and postoperative activity levels higher (p < 0.001) than the group 1 patients (p < 0.05), but that group 1 rated nipple position higher (p < 0.05). There was no significant difference between the two groups in terms of general aesthetic satisfaction. Physicians who evaluated patient photos ranked the scars of group 2 as significantly superior to those of group 1 (p < 0.01), whereas they did not rate other features as significantly different. However students could not determine any superiority of any feature between the two groups. The no-vertical-scar technique gives the impression of a breast that has not undergone surgery because it leaves no scars in the infraareolar area and invisible scars in other areas. This situation improves the degree of satisfaction for patients in the postoperative period. When the general aesthetic success and the ratio of complications were evaluated, the no-vertical-scar technique was found to be just as successful as the T- scar technique, which is practiced widely.     

Comparative study of wound healing in rat skin following incision with a novel picosecond infrared laser (PIRL) and different surgical modalities

Background and Objective

As a result of wound healing the original tissue is replaced by dysfunctional scar tissue. Reduced tissue damage during surgical procedures beneficially affects the size of the resulting scar and overall healing time. Thus the choice of a particular surgical instrument can have a significant influence on the postoperative wound healing. To overcome these problems of wound healing we applied a novel picosecond infrared laser (PIRL) system to surgical incisions. Previous studies indicated that negligible thermal, acoustic, or ionization stress effects to the surrounding tissue results in a superior wound healing.

Study Design/Materials and Methods

Using the PIRL system as a surgical scalpel, we performed a prospective wound healing study on rat skin and assessed its final impact on scar formation compared to the electrosurgical device and cold steel. As for the incisions, 6 full‐thickness, 1‐cm long‐linear skin wounds were created on the dorsum of four rats using the PIRL, an electrosurgical device, and a conventional surgical scalpel, respectively. Rats were euthanized after 21 days of wound healing. The thickness of the subepithelial fibrosis, the depth and the transverse section of the total scar area of each wound were analyzed histologically.

Results

After 21 days of wound healing the incisions made by PIRL showed minor scar tissue formation as compared to the electrosurgical device and the scalpel. Highly significant differences (P < 0.001) were noted by comparing the electrosurgical device with PIRL and scalpel. The transverse section of the scar area also showed significant differences (P = 0.043) when comparing PIRL (mean: 141.46 mm²; 95%CI: 105.8–189.0 mm²) with scalpel incisions (mean: 206.82 mm²; 95%CI: 154.8–276.32 mm²). The subepithelial width of the scars that resulted from using the scalpel were 1.3 times larger than those obtained by using the PIRL (95%CI: 1.0–1.6) though the difference was not significant (P < 0.083).

Conclusions

The hypothesis that PIRL results in minimal scar formation with improved cosmetic outcomes was positively verified. In particular the resection of skin tumors or pathological scars, such as hypertrophic scars or keloids, are promising future fields of PIRL application. Lasers Surg. Med. 48:385–391, 2016. © 2016 The Authors. Lasers in Surgery and Medicine Published by Wiley Periodicals, Inc.