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We demonstrate the use of the near-infrared attenuation coefficient, measured using optical coherence tomography (OCT), in longitudinal assessment of hypertrophic burn scars undergoing fractional laser treatment. The measurement method incorporates blood vessel detection by speckle decorrelation and masking, and a robust regression estimator to produce 2D en face parametric images of the attenuation coefficient of the dermis. Through reliable co-location of the field of view across pre- and post-treatment imaging sessions, the study was able to quantify changes in the attenuation coefficient of the dermis over a period of ~20 weeks in seven patients. Minimal variation was observed in the mean attenuation coefficient of normal skin and control (untreated) mature scars, as expected. However, a significant decrease (13 ± 5%, mean ± standard deviation) was observed in the treated mature scars, resulting in a greater distinction from normal skin in response to localized damage from the laser treatment. By contrast, we observed an increase in the mean attenuation coefficient of treated (31 ± 27%) and control (27 ± 20%) immature scars, with numerical values incrementally approaching normal skin as the healing progressed. This pilot study supports conducting a more extensive investigation of OCT attenuation imaging for quantitative longitudinal monitoring of scars. (Figure presented.) En face 2D OCT attenuation coefficient map of a treated immature scar derived from the pre-treatment (top) and the post-treatment (bottom) scans. (Vasculature (black) is masked out.) The scale bars are 0.5 mm.

This study presents the first in vivo longitudinal assessment of scar vasculature in ablative fractional laser treatment using optical coherence tomography (OCT). A method based on OCT speckle decorrelation was developed to visualize and quantify the scar vasculature over the treatment period. Through reliable co-location of the imaging field of view across multiple imaging sessions, and compensation for motion artifact, the study was able to track the same scar tissue over a period of several months, and quantify changes in the vasculature area density. The results show incidences of occlusion of individual vessels 3 days after the first treatment. The subsequent responses ˜20 weeks after the initial treatment show differences between immature and mature scars. Image analysis showed a distinct decrease (25 ± 13%, mean ± standard deviation) and increase (19 ± 5%) of vasculature area density for the immature and mature scars, respectively. This study establishes the feasibility of OCT imaging for quantitative longitudinal monitoring of vasculature in scar treatment. En face optical coherence tomography vasculature images pre-treatment (top) and ˜20 weeks after the first laser treatment (bottom) of a mature burn scar. Arrows mark the same vessel pattern.

Burn injury can lead to abnormal sensory function at both the injury and at distant uninjured sites. Here, we used a mouse model to investigate return of nociceptive function and reinnervation of the skin at the wound and uninjured distant sites following a 3% total burn surface area full-thickness burn injury. We have previously shown that topical application of zinc-metallothionein-IIA (Zn 7 -MT-IIA) accelerates healing following burn injury, and here, we investigated the potential of Zn 7 -MT-IIA to enhance reinnervation and sensory recovery. In all burn-injured animals, there was a significant reduction in nociceptive responses (Semmes-Weinstein filaments) at locations near and distant to the wound up to 8 weeks following injury. Cutaneous nerve reinnervation (assessed using protein gene product 9.5 immunohistochemistry) of the wound center was slow in the epidermis but rapid in the dermis. In the dermis, nerves subsequently degenerated both at the wound center and in distant uninjured areas. In contrast, epidermal nerve densities in the distant uninjured areas returned to normal, uninjured levels. Zn 7 -MT-IIA did not influence return of nociceptive function nor reinnervation. We conclude that burn injury compromises nociceptive function and nerve regeneration both at the injury site and systemically; thus, therapies in addition to Zn 7 -MT-IIA should be explored to return normal sensory function.

Aim: To estimate temporal trends in burn injury hospitalisations, mortality and hospital stay, for older adults with a burn-related hospitalisation. Methods: De-identified data of all incident burn hospitalisations for adults 60 years and older in Western Australia from 1983-2008 were analysed. Poisson regression analyses were used to estimate temporal trends in hospital admissions and mortality. Zero truncated negative binomial regression analysis was used to identify factors associated with hospital stay. Results: Between 1983 and 2008, hospitalisation rates increased for scalds (incident rate ratio (IRR) 1.01, 95% CI: 1.00-1.02) and contact burns (IRR 1.05, 95% CI: 1.03-1.07) while a significant reduction in flame hospitalisation rates (IRR 0.93, 95% CI: 0.92-0.94) was estimated. No significant changes in length of stay or burn-related mortality were estimated. Conclusions: Burn safety and prevention strategies that include first aid education need to be developed that target older adults living in their homes, to decrease their risk of sustaining burn injuries. Language: en

Severe injury to the epidermal barrier often results in scarring and life-long functional deficits, the outcome worsening with a number of factors including time taken to heal. We have investigated the potential of exogenous metallothionein IIA (Zn7-MT-IIA), a naturally occurring small cysteine-rich protein, to accelerate healing of burn wounds in a mouse model. Endogenous MT-I/II expression increased in basal keratinocytes concurrent with reepithelialization after a burn injury, indicating a role for MT-I/II in wound healing. In vitro assays of a human keratinocyte cell line indicated that, compared with saline controls, exogenous Zn7-MT-IIA significantly increased cell viability by up to 30% (p 0.05). Topical administration of exogenous Zn7-MT-IIA (2 μg/mL) in vivo, immediately postburn accelerated healing, promoted faster reepithelialization (3 days: phosphate-buffered saline (PBS), 8.9±0.3 mm diameter vs. MT-I/II, 7.1±0.7 mm; 7 days: PBS 5.8±0.98 mm vs. MT-I/II, 3.6±1.0 mm, p