Wound healing in radiated skin: pathophysiology and treatment options

Pharyngeal Mucosal Margin Vessel Counts Predict Pharyngocutaneous Fistula in Salvage Laryngectomy

OBJECTIVE

We evaluated vessel counts in the pharyngeal mucosal margins of patients who underwent salvage laryngectomy to establish whether mucosal vascularity might predict fistula risk.

STUDY DESIGN

Retrospective cohort.

SETTING

Tertiary Medical Center.

METHODS

Patients who underwent salvage total laryngectomy at our institution between 1999 and 2015 were identified. Pharyngeal mucosal margins from laryngectomy specimens were evaluated histologically for each patient, and vessel counts were performed on 5 ×10 images. The primary outcome measure was fistula within 30 days of surgery and mean vessel counts were assessed as the principle explanatory variable.

RESULTS

Seventy patients were included and 40% developed a postoperative fistula. There was a large difference in the mean vessel count in patients who did develop fistula (48.6 vessels/×10 field) compared to those who did not (34.7 vessels/×10 field). A receiver operative characteristic curve found that a cutoff value of 33.9 vessels/×10 field provided a sensitivity of 75% and specificity of 62% to predict the likelihood of fistula occurrence (area under the curve = 0.71, 95% confidence interval [CI]: 0.59-0.83). In a binary logistic regression, patients with vessel counts greater than 33.9 had a 5-fold increased risk of developing fistula (95% CI: 1.8-16.45). Histologically, vessels in the pharyngeal mucosa of patients who developed fistulas were more disorganized.

CONCLUSION

After salvage laryngectomy, patients with higher mean mucosal margin vessel counts are at increased risk of fistula. The mechanism is unknown, but the disorganization of the vasculature may contribute to poor wound healing. Vessel counting may allow for fistula risk stratification and guide postoperative care.

Cutaneous Radiation Injuries: REAC/TS Clinical Experience

The Radiation Emergency Assistance Center/Training Site (REAC/TS) is one of the US Department of Energy (DOE)/National Nuclear Security Administration (NNSA) Nuclear Emergency Response Team (NEST) assets and has been responding to radiological incidents since 1976. REAC/TS is in the Oak Ridge Institute for Science and Education (ORISE). A critical part of the REAC/TS mission is to provide emergency response, advice, and consultation on injuries and illnesses caused from ionizing radiation. Fortunately, radiation injuries are not frequent, but when they occur, they are more likely to be cutaneous radiation injuries (CRI) or internal contamination. In this paper, we will review selected cases from the REAC/TS experience in order to illustrate cutaneous patterns of injury and treatment options.

Predicted factors of surgical site infection in glioblastoma patients: A meta-analysis

Surgical site infection (SSI) is one of the common postoperative complications after craniotomy for glioblastoma patients. Previous studies have investigated the risk factors for SSI in patients with glioblastoma. Whereas big differences in research results exist, and the correlation coefficients of different research results are quite different. A meta-analysis was conducted to examine the risk factors related to surgical site infection in patients with glioblastoma. We searched English databases to collect case-control studies or cohort studies published before 15 October 2023 including PubMed, Web of Science, Embase. The risk of bias of the included studies was assessed via Newcastle-Ottawa Scale. The analysis was performed using RevMan 5.4.1 tool. A total of 4 articles (n = 2222) were selected in this meta-analysis. The following risk factors were presented to be correlated with SSI in glioblastoma: irradiation (OR = 1.88, 95% CI [0.46, 7.60]), more than 3 surgeries (OR = 2.99, 95% CI [1.47, 6.08]). Occurrence of SSI is influenced by a variety of factors. Thus, we should pay close attention to high-risk subjects and take crucial targeted interventions to lower the SSI risk following craniotomy. Owing to the limited quality and quantity of the included studies, more rigorous studies with adequate sample sizes are needed to verify the conclusion.

The Influence of Different Irradiation Regimens on Inflammation and Vascularization in a Random-Pattern Flap Model

BACKGROUND

Irradiation plays an important role in the oncological treatment of various tumor entities. The aim of the study was to investigate the influence of different irradiation regimens on random-pattern flaps at the molecular and histopathological levels.

METHODS

Twenty-five rats underwent harvesting of bilateral random-pattern fasciocutaneous flaps. The right flaps received irradiation, while the left flaps served as non-irradiated intraindividual controls. Five rats served as a non-irradiated control group. Four different irradiation regimens with give rats each were tested: 20 Gy postoperatively, 3 × 12 Gy postoperatively, 20 Gy preoperatively, and 3 × 12 Gy preoperatively. Two weeks after surgery, HE staining and immunohistochemical staining for CD68 and ERG, as well as PCR analysis to detect Interleukin 6, HIF-1α, and VEGF, were performed.

RESULTS

A postoperative cumulative higher dose of irradiation appeared to result in an increase in necrosis, especially in the superficial layers of the flap compared to preoperative or single-stage irradiation. In addition, we observed increased expression of VEGF and HIF-1α in all irradiation groups.

CONCLUSION

Even though no statistically significant differences were found between the different groups, there was a tendency for fractional postoperative irradiation with a higher total dose to have a more harmful effect compared to preoperative or single-dose irradiation.

Risk factors and prognostic significance of infection of totally implantable vascular access port in solid tumor patients: A prospective cohort study

OBJECTIVES

Totally implantable venous access ports (TIVAP) are devices mainly used to deliver antineoplastic chemotherapies, of which the insertion may be complicated by TIVAP-related infection (TIVAP-RI). This study aims to provide data on the risk factors for TIVAP-RI and its influence on patient prognosis.

PATIENTS AND METHODS

Prospective observational study including adult patients with solid tumors, in whom a TIVAP was inserted to deliver antineoplastic chemotherapy between January 2018 and October 2019. Factors associated with TIVAP-RI and one-year mortality were determined using multiple logistic regressions.

RESULTS

More than a thousand (1014) patients were included, among whom 48 (4.7%) presented with TIVAP-RI. Gram-positive cocci and Gram-negative bacilli represented 51% and 41% of the pathogens isolated, respectively. Young age (odds ratio [OR] 0.67; 95% Confidence Interval [0.53-0.83] per 10-year increase), WHO performance status ≥ 1 (OR 3.24 [1.52-7.79]), chemotherapy administration in the month before TIVAP placement (OR 2.26 [1.17-4.26]), and radiation therapy of the homolateral chest wall (OR 3.28 [1.51-6.67]) were independently associated with TIVAP-RI occurrence. During the year following TIVAP insertion, 287 (28%) patients died. TIVAP-RI was not associated with one-year mortality (OR 1.56 [0.75-3.19]).

CONCLUSION

TIVAP insertion in adult patients with solid tumors is associated with a low infection rate, which did not influence one-year mortality. In addition to young age and impaired health status, TIVAP insertion in the month following initiation of the antineoplastic chemotherapy and TIVAP insertion in an irradiated area are two newly reported preventable TIVAP-RI risk factors.

Effects of negative pressure wound therapy on surgical site wound infections after cardiac surgery: A meta-analysis

We conducted a comprehensive analysis to evaluate the benefits of negative pressure wound therapy (NPWT) versus traditional dressings in preventing surgical site infections in patients undergoing cardiac surgery. We thoroughly examined several databases, including PubMed, EMBASE, Cochrane Library, China National Knowledge Infrastructure (CNKI), VIP, Chinese Biomedical Literature Database (CBM) and Wanfang, from inception until July 2023. Two independent researchers were responsible for the literature screening, data extraction and quality assessment; analyses were performed using RevMan 5.4 software. Thirteen studies comprising 8495 patients were deemed relevant. A total of 2685 patients were treated with NPWT, whereas 5810 received conventional dressings. The findings revealed that NPWT was more effective in reducing surgical site infections after cardiac surgery than conventional dressings (4.88% vs. 5.87%, odds ratio [OR]: 0.50, 95% confidence intervals [CIs]: 0.40-0.63, p < 0.001). Additionally, NPWT was more effective in reducing deep wound infections (1.48% vs. 4.15%, OR: 0.36, 95% CI: 0.23-0.56, p < 0.001) and resulted in shorter hospital stays (SMD: -0.33, 95% CIs: -0.54 to -0.13, p = 0.001). However, the rate of superficial wound infections was not significantly affected by the method of wound care (3.72% vs. 5.51%, OR: 0.63, 95% CI: 0.32-1.23, p = 0.180). In conclusion, NPWT was shown to be advantageous in preventing postoperative infections and reducing hospital stay durations in patients undergoing cardiac surgery. Nonetheless, given the limitations in the number and quality of the included studies, further research is recommended to validate these findings.

Orchestration of Mesenchymal Stem/Stromal Cells and Inflammation During Wound Healing

Wound healing is a complex process and encompasses a number of overlapping phases, during which coordinated inflammatory responses following tissue injury play dominant roles in triggering evolutionarily highly conserved principals governing tissue repair and regeneration. Among all nonimmune cells involved in the process, mesenchymal stem/stromal cells (MSCs) are most intensely investigated and have been shown to play fundamental roles in orchestrating wound healing and regeneration through interaction with the ordered inflammatory processes. Despite recent progress and encouraging results, an informed view of the scope of this evolutionarily conserved biological process requires a clear understanding of the dynamic interplay between MSCs and the immune systems in the process of wound healing. In this review, we outline current insights into the ways in which MSCs sense and modulate inflammation undergoing the process of wound healing, highlighting the central role of neutrophils, macrophages, and T cells during the interaction. We also draw attention to the specific effects of MSC-based therapy on different pathological wound healing. Finally, we discuss how ongoing scientific advances in MSCs could be efficiently translated into clinical strategies, focusing on the current limitations and gaps that remain to be overcome for achieving preferred functional tissue regeneration.

Evaluation of the Effects of Radiation Therapy on Muscle Contractibility and Skin Healing: An Experimental Study of the Cancer Treatment Implications

BACKGROUND

Radiotherapy can affect healthy cells, resulting in side effects. This study aimed to assess the impact of radiotherapy on soft tissue in surgical wounds in rats.

METHODS

The animals were divided into four groups: control (S) group without irradiation, immediate irradiation (S-IIr) group receiving irradiation right after surgery, late irradiation (S-LIr) group receiving irradiation four weeks after surgery, and early irradiation (Ir-S) group receiving irradiation before surgery. The irradiated groups underwent two fractional stages of 15 Gy. Muscle contractibility (EMG) was evaluated at two different time points, and after 2 and 7 weeks, the animals were euthanized for histological analysis of the muscles and skin.

RESULTS

There was no significant difference between the EMG1 and EMG2 values of the S and S-LIr groups, but both S-IIr and Ir-S groups exhibited a statistically significant difference. The S group demonstrated a larger diameter of muscle fiber compared to other groups, showing a significant difference. In terms of skin analysis, the S-IIr group had the least inflammatory infiltrate and the highest amount of red fibers, differing significantly from the other groups.

CONCLUSIONS

Regardless of the duration, radiotherapy was found to have effects on the surrounding soft tissues, as concluded by this study.

Relationship between characteristics of glioma treatment and surgical site infections

PURPOSE

Surgical site infections (SSIs) after neurosurgery are common in daily practice. Although numerous reports have described SSIs in neurosurgery, reports specific to gliomas are limited. This study aimed to investigate the relationship between SSIs and glioma treatment characteristics, such as reoperations, radiation therapy, and chemotherapy.

METHODS

We examined 1012 consecutive patients who underwent craniotomy for glioma between November 2013 and March 2022. SSIs were defined as infections requiring reoperation during the observation period, regardless of their location. We retrospectively analyzed SSIs and patient factors.

RESULTS

During the observation period, SSIs occurred in 3.1% (31/1012). In the univariate analysis, three or more surgeries (P = 0.007) and radiation therapy (P = 0.03) were associated with SSIs, whereas intraoperative magnetic resonance imaging (MRI) was not significantly associated (P = 0.35). Three or more surgeries and radiation therapy were significantly correlated with each other (P < .0001); therefore, they were analyzed separately in the multivariate analysis. Three or more surgeries were an independent factor triggering SSIs (P = 0.02); in contrast, radiation therapy was not an independent factor for SSIs (P = 0.07). Several SSIs localized in the skin occurred more than 1 year after surgery.

CONCLUSIONS

Undergoing three or more surgeries for glioma is an independent risk factor for SSIs. Glioma SSIs can occur long after surgery. These results are considered characteristic of gliomas. We recommend careful long-term observation of patients at a high risk of SSIs.

A Chitosan-Coated Chamomile Microparticles Formulation to Prevent Radiodermatitis in Breast: A Double-blinded, Controlled, Randomized, Phase II Clinical Trial

PURPOSE

The aim was to evaluate the effect of a topical formulation containing chitosan-coated Chamomilla recutita (L.) rauschert microparticles regarding the incidence, grade, and days for the appearance of radiodermatitis (RD) in women with breast cancer.

METHODS

A double-blinded, controlled, randomized, phase II clinical trial developed with women diagnosed with breast cancer who will receive radiation therapy. The participants were randomly divided into 2 groups: control and treatment. They were followed up until the end of the treatment or the appearance of grade III RD.

RESULTS

Fifty-four women were included in the study. There is no significant difference between the groups in the incidence (88.9% vs. 88.9%, P=1.0) or time to develop any grade of RD (3 days of difference, P=0.300). A significant reduction was observed in the incidence (P=0.03) and in the time to appearance (7 d of difference, P=0.01) grade 2 or >RD. In the follow-up evaluation (15 d after the end of treatment), the Chamomile group presented a superior skin recovery than the control group (P=0.0343). High-intensity local symptoms as pain, and pruritus were significantly reduced in the Chamomile group.

CONCLUSIONS

Although no effect was observed with chamomile to reduce any grade of RD, it was effective to reduce grade 2 or >toxicity, to improve skin recovery and to diminish high-intensity local symptoms.

TRIAL REGISTRATION

Brazilian Registry of Clinical Trials (ReBEC): RBR-9hnftg, April 29, 2019.

The senescence-associated secretory phenotype: Fueling a wound that never heals

Wound healing is impaired with advanced age and certain chronic conditions, such as diabetes and obesity. Moreover, common cancer treatments, including chemotherapy and radiation, can cause unintended tissue damage and impair wound healing. Available wound care treatments are not always effective, as some wounds fail to heal or recur after treatment. Hence, a more thorough understanding of the pathophysiology of chronic, nonhealing wounds may offer new ideas for the development of effective wound care treatments. Cancers are sometimes referred to as wounds that never heal, sharing mechanisms similar to wound healing. We describe in this review how cellular senescence and the senescence-associated secretory phenotype (SASP) contribute to chronic wounds versus cancer.

Radiation ulcer treatment with hyperbaric oxygen therapy and haemoglobin spray: case report and literature review

OBJECTIVE

To explore the effectiveness of a combination of hyperbaric oxygen therapy and haemoglobin spray in radiation ulcer treatment.

METHOD

We reviewed the available literature and present a case report in which radiation ulcer was treated with a combination of hyperbaric oxygen therapy and haemoglobin spray.

RESULTS

After 30 sessions of hyperbaric oxygen therapy (2.4 ATA; 90 minutes each session) and administration of haemoglobin spray, the wounds showed gradual progress towards healing and a good granulating base was achieved. The wounds were closed after two months using a small split thickness skin graft.

CONCLUSION

A combination of hyperbaric oxygen therapy and haemoglobin spray was effective as a short course of treatment for radiation ulcers.

Exosomes derived from plasma: promising immunomodulatory agents for promoting angiogenesis to treat radiation-induced vascular dysfunction

Ionizing radiation (IR)-induced vascular disorders slow down tissue regeneration. Exosomes derived from plasma exhibit potential to promote angiogenesis; meanwhile, the immune microenvironment plays a significant role in the process. This study aimed to test the hypothesis that plasma exosomes promote angiogenesis in irradiated tissue by mediating the immune microenvironment. First, we explored the impact of IR on macrophages. We found that cell viability and capacity for promoting angiogenesis were decreased in irradiated macrophages compared to control macrophages. Then, we isolated and characterized rat plasma-derived exosomes (RP-Exos) which were defined as 40-160 nm extracellular vesicles extracted from rat plasma. Afterward, we evaluated the effects of RP-Exos on the behaviors of irradiated macrophages. Our results show that RP-Exos promoted cell proliferation. More importantly, we found that RP-Exos stimulated the immune microenvironment in a manner that improved the angiogenesis-related genes and proteins of irradiated macrophages. The supernatant of macrophage cell cultures was used as conditioned medium to treat human primary umbilical vein endothelial cells, further confirming the pro-angiogenic ability of macrophages receiving RP-Exo intervention. RP-Exos were used in vivo to treat irradiated skin or calvarial defects in irradiated Sprague-Dawley male rats. The results indicated the ability of RP-Exos to enhance angiogenesis and promote tissue regeneration. Our research suggested the potential of plasma exosomes to be used as immunomodulatory agents with angiogenic capacity to treat radiation-associated vascular disorders and facilitate tissue repair.

Reduction mammoplasty and mastopexy in the previously irradiated breast - a systematic review and meta-analysis

Breast cancer is the most common cancer diagnosed in women, and early stages are treated with lumpectomy and irradiation. Irradiation, however, leads to reduced vascularization and fibrosis, which may influence the cosmetic outcome unfavourably and increase complications after subsequent surgery on irradiated breasts. Patients with significant asymmetry after treatment may desire corrective reduction mammoplasty or mastopexy, but this may be associated with increased complication rates. This systematic review and meta-analysis aimed to investigate postoperative complication rates after bilateral reduction mammoplasty or mastopexy in women who had undergone unilateral lumpectomy and irradiation. PubMed, Medline, EMBASE and Cochrane databases were searched for eligible studies. After screening titles and abstracts, 14 full text studies were reviewed, and 7 of these were included in the analysis. The meta-analysis showed a significantly higher complication rate in the irradiated breast compared to the non-irradiated breast, rate ratio 4.82 (95% CI: 1.58, 14.70), p = 0.006. The complication rate was 54% in the irradiated breast (58/107) compared to 8% (9/107) in the non-irradiated breast (p = 0.034). This study suggests that reduction mammoplasty or mastopexy in the previously irradiated breast is associated with a significantly increased risk of complications. Careful patient selection and information are paramount in the treatment of this patient group.

Cryogel/hydrogel biomaterials and acupuncture combined to promote diabetic skin wound healing through immunomodulation

Unhealed chronic wounds often deteriorate into multiple infection with several kinds of bacteria and excessive proteolytic wound exudate and remains one of the common healthcare issues. Here, the functional and antimicrobial hydrogel and cryogel biomaterials were prepared from glycol chitosan and a novel biodegradable Schiff base crosslinker difunctional polyurethane (DF-PU). The cryogel exhibited ~2730 ± 400% of water absorption with abundant macropores and 86.5 ± 1.6% of porosity formed by ice crystal as well as ~240% cell proliferation effect; while the hydrogel demonstrated considerable antimicrobial activity and biodegradability. As an optimized procedure to treat the diabetic skin wound in a rat model, the combined application of adipose stem cell-seeded cryogel/hydrogel biomaterials on the wound and acupuncture surrounding the wound may attain 90.34 ± 2.3% of wound closure and secure the formation of granulation tissue with sufficient microvessels and complete re-epithelialization in 8 days. The average increases in the superficial temperature of wounded animals after acupuncture were about 1-2 °C. Through the activation of C3a and C5a, the increased secretion of cytokines SDF-1 and TGFβ-1, as well as the down-regulation of proinflammatory cytokines TNF-α and IL-1β, the combined treatment of stem cell-seeded cryogel/hydrogel biomaterials and acupuncture on wounds produced synergistic immunomodulatory effects. The strategy using the combined treatment of biomaterials, stem cells, and acupuncture reveals a perspective new approach to accelerate the tissue regeneration.

Dermatologic Sequelae Associated with Radiation Therapy

Radiation therapy is a mainstay for the treatment of primary malignancies and metastatic disease and is associated with several dermatological adverse events that are underreported in the literature. The objective of this paper was to review the literature regarding cutaneous manifestations associated with radiation therapy in order to promote awareness of the cutaneous radiation therapy-associated adverse effects. This extensive literature review was performed using the Pubmed and Embase databases. Studies were reviewed for relevance and critical evidence pertaining to cutaneous manifestations of radiation therapy. The most commonly reported cutaneous sequelae associated with radiation therapy include radiation dermatitis, non-melanoma skin cancer, radiation-associated angiosarcoma, morphea, bullous pemphigoid, lymphangioma circumscriptum, and pseudosclerodermatous panniculitis. For many of these conditions, only case reports or case series exist and there is an absence of large-scale cohort studies. Despite these limitations, this review describes the wide range of dermatological adverse events associated with radiation therapy.

Mesenchymal Stem Cells for Chronic Wound Healing: Current Status of Preclinical and Clinical Studies

Healing skin wounds with anatomic and functional integrity, especially under chronic pathological conditions, remain an enormous challenge. Due to their outstanding regenerative potential, mesenchymal stem cells (MSCs) have been explored in many studies to determine the healing ability for difficult-to-treat diseases. In this article, we review current animal studies and clinical trials of MSC-based therapy for chronic wounds, and discuss major challenges that confront future clinical applications. We found that a wealth of animal studies have revealed the versatile roles and the benefits of MSCs for chronic wound healing. MSC treatment results in enhanced angiogenesis, facilitated reepithelialization, improved granulation, and accelerated wound closure. There are some evidences of the transdifferentiation of MSCs into skin cells. However, the healing effect of MSCs depends primarily on their paracrine actions, which alleviate the harsh microenvironment of chronic wounds and regulate local cellular responses. Consistent with the findings of preclinical studies, some clinical trials have shown improved wound healing after transplantation of MSCs in chronic wounds, mainly lower extremity ulcers, pressure sores, and radiation burns. However, there are some limitations in these clinical trials, especially a small number of patients and imperfect methodology. Therefore, to better define the safety and efficiency of MSC-based wound therapy, large-scale controlled multicenter trials are needed in the future. In addition, to build a robust pool of clinical evidence, standardized protocols, especially the cultivation and quality control of MSCs, are recommended. Altogether, based on current data, MSC-based therapy represents a promising treatment option for chronic wounds. Impact statement Chronic wounds persist as a significant health care problem, particularly with increasing number of patients and the lack of efficient treatments. The main goal of this article is to provide an overview of current status of mesenchymal stem cell (MSC)-based therapy for chronic wounds. The roles of MSCs in skin wound healing, as revealed in a large number of animal studies, are detailed. A critical view is made on the clinical application of MSCs for lower extremity ulcers, pressure sores, and radiation burns. Main challenges that confront future clinical applications are discussed, which hopefully contribute to innovations in MSC-based wound treatment.

Vesico-urethral anastomotic stenosis following radical prostatectomy: a multi-institutional outcome analysis with a focus on endoscopic approach, surgical sequence, and the impact of radiation therapy

OBJECTIVES

To investigate the predictors of recurrence and of de novo incontinence in patients treated by transurethral incision or resection for vesico-urethral anastomotic stenosis (VUAS) after radical prostatectomy.

MATERIAL AND METHODS

All patients undergoing endoscopic treatment for VUAS between March 2009 and October 2016 were identified in our multi-institutional database. Digital chart reviews were performed and patients contacted for follow-up. Recurrence was defined as any need for further instrumentation or surgery, and de-novo-incontinence as patient-reported outcome.

RESULTS

Of 103 patients undergoing endoscopic VUAS treatment, 67 (65%) underwent transurethral resection (TR) and 36 (35%) transurethral incision (TI). TI was performed more frequently as primary treatment compared to TR (58% vs. 37%; p = 0.041). Primary and repeated treatment was performed in 46 (45%) and 57 patients (55%), respectively. Overall, 38 patients (37%) had a history of radiation therapy. There was no difference in time to recurrence for primary vs repeat VUAS treatment, previous vs no radiation, TR compared to TI (all p > 0.08). Regarding treatment success, no difference was found for primary vs. repeat VUAS treatment (50% vs. 37%), previous radiation vs. no radiation (42% vs. 43%), and TR vs. TI (37% vs. 53%; all p ≥ 0.1). Postoperative de novo incontinence was more common after TI vs. TR (31% vs. 12%; p = 0.032), no difference was observed for previous radiation therapy vs. no radiation therapy (18% vs. 18%; p > 0.9) or primary vs. repeat VUAS treatment (22% vs. 16%; p = 0.5).

CONCLUSION

VUAS recurrence after endoscopic treatment is not predictable. Endoscopic treatment with TI showed a higher risk for de novo incontinence than TR, and previous irradiation and the number of treatments do not influence incontinence.

Design and evaluation of mesenchymal stem cells seeded chitosan/glycosaminoglycans quaternary hydrogel scaffolds for wound healing applications

The main goal of this study was the design, development and characterization of a chitosan based scaffolding substrate including three glycosaminoglycans and collagen to provide an optimal microenvironment for human mesemchymal stem cells isolated from adipose tissue (hMSCs). Chitosan scaffolds provide a moist wound environment which promotes healing and epidermal regeneration. Furthermore, the importance of extracellular molecules such as glycosaminoglycans in wound healing makes them essential ingredients in these types of formulations. The physical properties of hydrogels scaffolds and stability were investigated. The scaffolds were evaluated by structural and microscopic assays, as well as cell culture analyses. The hydrogel with best suitable properties was selected as candidate scaffold for hMSCs encapsulation. The viability of hMSCs remained above 75%, indicating good cell viability. The number of living hMSCs in the scaffold reached a steady state up to ~100% at days 5 and 7. Scanning electron microscopy showed irregular compartments with the presence of the hMSCs. These findings indicated that our hydrogel scaffold provided a suitable niche for cell viability which could be considered a promising candidate for further in vivo studies.

Effect of preoperative immunonutrition on complications after salvage surgery in head and neck cancer

Background

Patients undergoing salvage surgery for recurrent head and neck squamous cell carcinoma are at high risk of postoperative complications due to the adverse effects of radiotherapy on wound healing. Malnutrition is an additional risk factor and we tested the hypothesis that preoperative administration of immunonutrition would decrease complications in this high risk population.

Methods

This single armed study with historical control included consecutive patients undergoing salvage surgery for recurrent head and neck squamous cell carcinoma. We compared outcomes before and after implementation of preoperative immunonutrition and adjusted the regression analysis for gender, age, body mass index, Nutritional Risk Screening (NRS 2002), tobacco and alcohol consumption, tumor localization, tumor stage, and type of surgery. The primary endpoint was overall complications from surgery within a follow-up of 30 days.

Results

Ninety-six patients were included (intervention group: 51, control group: 45). Use of preoperative immunonutrition was associated with a significant reduction in overall complications (35% vs. 58%, fully-adjusted odds ratio 0.30 (95%CI 0.10–0.91, p = 0.034). Length of hospital stay was also significantly reduced (17 days vs. 6 days, p = < 0.001). No differences in mortality and hospital readmission were found. These results remained robust in multivariate analysis.

Conclusions

In patients undergoing salvage surgery for recurrent head and neck squamous cell carcinoma, preoperative immunonutrition exhibited favorable effects on the complication rate and consequently reduced the length of hospital stay. By improving both tissue regeneration and immune response, immunonutrition may help to improve surgical outcomes in this high-risk population.

Fat Chance: The Rejuvenation of Irradiated Skin

Radiotherapy (RT) helps cure and palliate thousands of patients with a range of malignant diseases. A major drawback, however, is the collateral damage done to tissues surrounding the tumor in the radiation field. The skin and subcutaneous tissue are among the most severely affected regions. Immediately following RT, the skin may be inflamed, hyperemic, and can form ulcers. With time, the dermis becomes progressively indurated. These acute and chronic changes cause substantial patient morbidity, yet there are few effective treatment modalities able to reduce radiodermatitis. Fat grafting is increasingly recognized as a tool able to reverse the fibrotic skin changes and rejuvenate the irradiated skin. This review outlines the current progress toward describing and understanding the cellular and molecular effects of fat grafting in irradiated skin. Identification of the key factors involved in the pathophysiology of fibrosis following RT will inform therapeutic interventions to enhance its beneficial effects.

Therapeutic Effects of Human Adipose-Derived Products on Impaired Wound Healing in Irradiated Tissue

BACKGROUND

Clinical sequelae of irradiation result in tissue devitalization (e.g., ischemia, fibrosis, and atrophy) where wound healing capacity is impaired. Fat-derived products may work to treat such pathology.

METHODS

Nonlethal irradiation at various doses (5, 10, and 15 Gy) and frequencies (one to three times on sequential days) was delivered to dorsal skin of nude mice, and subsequent gross and microscopic changes were evaluated for up to 4 weeks. Cutaneous punch wounds were then created to compare wound healing in irradiated and nonirradiated states. Wounds were also locally injected with vehicle, cultured adipose-derived stem cells, centrifuged fat tissue, or micronized cellular adipose matrix, and the therapeutic impact was monitored for up to 15 days.

RESULTS

Nude mice given total doses greater than 15 Gy spontaneously developed skin ulcers, and radiation damage was dose-dependent; however, a fractionated irradiation protocol was able to reduce the damage. Histologic assessment revealed dose-dependent dermal fibrosis/thickening and subcutaneous atrophy. Dose-dependent (5 to 15 Gy) impairment of wound healing was also evident. At the highest dosage (15 Gy three times), open wounds persisted on day 15. However, wounds injected with cultured adipose-derived stem cells were nearly healed on day 12, and those treated with injection of centrifuged fat or micronized tissue healed faster than untreated controls (p < 0.05). There was no significant differences between treated groups.

CONCLUSIONS

Tissue devitalization by irradiation was dose-dependent, although fractionated protocols helped to reduce it. Adipose-derived stem cells and other fat-derived products harboring adipose-derived stem cells successfully revitalized irradiated tissues and accelerated wound healing.

Plasma-based biomaterials for the treatment of cutaneous radiation injury

Cutaneous wounds caused by an exposure to high doses of ionizing radiation remain a therapeutic challenge. While new experimental strategies for treatment are being developed, there are currently no off‐the‐shelf therapies for the treatment of cutaneous radiation injury that have been proven to promote repair of the damaged tissues. Plasma‐based biomaterials are biologically active biomaterials made from platelet enriched plasma, which can be made into both solid and semi‐solid forms, are inexpensive, and are available as off‐the‐shelf, nonrefrigerated products. In this study, the use of plasma‐based biomaterials for the mitigation of acute and late toxicity for cutaneous radiation injury was investigated using a mouse model. A 2‐cm diameter circle of the dorsal skin was irradiated with a single dose of 35 Gy followed by topical treatment with plasma‐based biomaterial or vehicle once daily for 5 weeks postirradiation. Weekly imaging demonstrated more complete wound resolution in the plasma‐based biomaterial vs. vehicle group which became statistically significant (p < 0.05) at weeks 12, 13, and 14 postmaximum wound area. Despite more complete wound healing, at 9 and 17 weeks postirradiation, there was no statistically significant difference in collagen deposition or skin thickness between the plasma‐based biomaterial and vehicle groups based on Masson trichrome staining nor was there a statistically significant difference in inflammatory or fibrosis‐related gene expression between the groups. Although significant improvement was not observed for late toxicity, plasma‐based biomaterials were effective at promoting wound closure, thus helping to mitigate acute toxicity.

Clotrimazole multiple W/O/W emulsion as anticandidal agent: Characterization and evaluation on skin and mucosae

Clotrimazole (CLT) was formulated in a multiple W/O/W emulsion (ME) with the aim of evaluating its potential as topical anticandidal agent and comparing with marketed products. A previously evaluated CLT-ME was selected and physicochemically characterized. The in vitro release behavior and the ex vivo permeation profiles were assessed using Franz diffusion cells using three different types of biological membranes: human skin and porcine buccal, sublingual and vaginal mucosae. The antifungal activity against Candida strains was also tested. Results showed CLT-MEs sizes of 29.206 and 47.678 μm with skin compatible pH values of 6.47 and 6.42 exhibiting high zeta potential values of -55.13 and -55.59 mV with dependence on the pH variation. The physicochemical stability was kept for a period of 180 days of storage at room temperature. CLT-MEs exhibited pseudoplastic behavior with hysteresis areas and viscosities of 286 and 331 mPa⋅s showing higher spreadability properties than commercial counterparts. An improved CLT release pattern was supplied by the ME system following a hyperbolic model. Likewise, ME system gave higher skin permeation flux of CLT than commercial reference. CLT amounts retained in the skin and mucosae were also higher than commercial references, which coupled with the higher antimycotic efficacy make CLT-MEs a great tool for clinical investigation of topical candidiasis treatments.

Biopharmaceutical profile of a clotrimazole nanoemulsion: Evaluation on skin and mucosae as anticandidal agent

Clotrimazole (CLT) was formulated in a nanoemulsion (NE) for the topical treatment of candidiasis consisting of 10% labrafac^® lipophile, 60% labrasol^®:capryol^® 90 mixture (ratio 4:1) and 30% propylene glycol. Physicochemical properties, stability, rheology, in vitro drug release, ex vivo drug permeation through human skin and porcine buccal, sublingual and vaginal mucosae, antifungal efficacy, as well as in vivo skin tolerance were evaluated. 1% CLT-NE (CLT-NE1) and 2% CLT-NE (CLT-NE2) exhibited 153 ± 17.25 and 186 ± 15.38 nm droplet sizes, low polydispersity indexes, negative zeta potentials and biocompatible pH values. The CLT-NEs exhibited typical Newtonian profiles with viscosities of 42.14 ± 0.037 mPa·s and 41.35 ± 0.041 mPa·s, respectively and higher extensibility properties than commercial counterparts retaining their physicochemical properties for 180 days. NEs provided a sustained release of drug according to the first order model. Similar skin permeation properties were observed between CLT-NE1 and commercial reference. However, significant higher CLT amounts retained in mucosae were provided by CLT-NE2 when compared with references. Antifungal efficacies were also higher than commercial references, and the in vivo tolerance study confirmed the suitability for topical application, making CLT-NEs a great tool for clinical investigation of topical candidiasis treatments.

Influence of Backscatter Radiation on Cranial Bone Fixation Devices

Postoperative radiation can cause ulcer formation, leading to the denudation of skin over alloplastic materials. The influence of backscatter radiation from fixation devices has not been investigated. The aim of this study is to evaluate backscatter dose variations for different cranial bone fixation devices in an experimental model designed to simulate postoperative radiotherapy. The authors assessed the radiation backscatter doses associated with resorbable (PLLA-PGA) and titanium plates. The samples were irradiated with 6 and 10 MV photon beams from a linear accelerator. Measurements were obtained using an ionization chamber and radiochromic films cut from the same batch. As a result, the backscatter radiation of water and PLLA-PGA proportionally decreased as the depth increased. However, the backscatter radiation of the titanium plate increased just above the plate. This depth lies in the region of the scalp. Each material showed a dose of radioactivity that was higher at 10 MV than that at 6 MV. These devices showed a significant difference, which suggested that these materials amplified the dose compared with water at 6 MV. In conclusion, it is supposed that PLLA-PGA should be used to fix the cranium to decrease the potential for radiation ulcers.

An injectable non-cross-linked hyaluronic-acid gel containing therapeutic spheroids of human adipose-derived stem cells

For chronic wounds, the delivery of stem cells in spheroidal structures can enhance graft survival and stem cell potency. We describe an easy method for the 3D culture of adipose-derived stem/stromal cells (ASCs) to prepare a ready-to-use injectable. We transferred suspensions of monolayer-cultured ASCs to a syringe containing hyaluronic acid (HA) gel, and then incubated the syringe as a 3D culture vessel. Spheroids of cells formed after 12 h. We found that 6 × 10⁶ ASCs/ml in 3% HA gel achieved the highest spheroid density with appropriate spheroid sizes (20-100 µm). Immunocytology revealed that the stem cell markers, NANOG, OCT3/4, SOX-2, and SSEA-3 were up-regulated in the ASC spheroids compared with those in nonadherent-dish spheroids or in monolayer cultured ASCs. In delayed wound healing mice models, diabetic ulcers treated with ASC spheroids demonstrated faster wound epithelialization with thicker dermis than those treated with vehicle alone or monolayer cultured ASCs. In irradiated skin ulcers in immunodeficient mice, ASC spheroids exhibited faster healing and outstanding angiogenic potential partly by direct differentiation into α-SMA+ pericytes. Our method of 3D in-syringe HA gel culture produced clinically relevant amounts of ready-to-inject human ASC microspheroids that exhibited superior stemness in vitro and therapeutic efficacy in pathological wound repair in vivo.

Influence of backscatter radiation on cranial reconstruction implants

OBJECTIVE

We aimed to evaluate backscatter dose variations in different cranial bone implant materials in an experimental model designed to simulate post-operative radiotherapy.

METHODS

We assessed the radiation backscatter doses associated with sheet- and mesh-type titanium plates and hydroxyapatite (HAP) samples (porosity: 35%, 50% and 85%). The samples were irradiated with 6- and 10-MV photon beams from a linear accelerator. Measurements were obtained using an ionization chamber and radiochromic films cut from the same batch.

RESULTS

At 6 MV, the titanium sheet showed the highest peak for backscattered radiation, followed by (in decreasing order) HAP30%, HAP50%, titanium mesh and HAP85%. At 10 MV, HAP30% showed the highest peak, followed by HAP50%, titanium sheet, titanium mesh and HAP85%. The peaks were at different depths in the titanium and HAP samples. The thickness of the human scalp is approximately 7 mm; therefore, measurements were obtained 0-7 mm above the implants to assess the likely dose on the scalp. A comparison of the maximum dose on the scalp showed the titanium sheet had the highest dose at both 6 and 10 MV.

CONCLUSION

The backscatter dose differed with the density of the material and the backscatter depth was different for each material. Advances in knowledge: Ulcer formation due to radiotherapy after brain tumour depends on not only radiation but also the implant material. Therefore, the density and type of implant material should be considered when planning radiotherapy and selecting bone reconstruction materials.

Hyperbaric oxygen therapy for a refractory skin ulcer after radical mastectomy and radiation therapy: a case report

Background

Radiation therapy is performed as an adjuvant therapy when indicated following surgical resection of malignant tumors. However, radiation exposure induces acute or chronic dermatitis, depending on the radiation dose, interval, tissue volume, or irradiated area of the body. Radiation-induced skin ulcers and osteomyelitis of the underlying bone are intractable late-stage complications of radiation therapy, and often require reconstructive surgery to cover exposed tissue. Hyperbaric oxygen therapy has been suggested as a treatment for delayed radiation injury with soft tissue and bony necrosis.

Case presentation

A 74-year-old Japanese female underwent left radical mastectomy for breast cancer (T3N3M0, stage IIIB) in 1987. Radiation therapy was initiated 6 weeks after the surgery. She received telecobalt-60 in a total dose of 50 Gy with 25 fractions to the left supraclavicular, parasternal and left axillary regions, and electron treatment (9 MeV) in a total dose of 50 Gy in 25 fractions to the left chest wall. After irradiation, her skin became thinner and more fragile on the left chest wall, but no severe infections were observed. She noticed a small ulcer that repeatedly healed and recurred in 2000. She visited the hospital where she received radiation therapy and was treated for a skin ulcer on the left chest wall in December 2012. A fistula developed and then pus was discharged in January 2013. She was referred to the hyperbaric medical center in February 2013, and the fistula (1.5 × 3 cm) with pus discharge was observed. She was diagnosed with a late-onset radiation-induced skin ulcer that developed 25 years after radical mastectomy. HBO₂ (2.5 atmospheres absolute with 100% oxygen for 60 minutes) was indicated for the refractory ulcer and osteomyelitis of the ribs. The patient was treated with HBO₂ a total of 101 times over the course of 1 year and completely recovered.

Conclusions

Hyperbaric oxygen therapy can be performed safely for even more than 100 sessions in patients with radiation-induced skin ulcers and osteomyelitis. Hyperbaric oxygen therapy can be considered as an alternative, conservative treatment when surgical resection for late-onset, radiation-induced skin ulcers is not indicated because of fragile skin in the irradiated areas.

Patterns of major wound complications following multidisciplinary therapy for lower extremity soft tissue sarcoma

BACKGROUND AND OBJECTIVES

The purpose of this study was to determine the pattern and timing of major wound complications (MWCs) in patients at our institution who received multimodality treatment for lower extremity soft tissue sarcoma (LE-STS) and to evaluate the impact of MWCs on tumor control and patient outcomes.

METHODS

The medical records of 102 LE-STS patients treated with limb-sparing surgery and radiation therapy were reviewed. MWCs were defined as secondary operations with anesthesia, seroma/hematoma aspiration, admission for IV antibiotics, or persistent deep packing.

RESULTS

MWCs occurred in 22% of patients, with 45% of events occurring >120 days after resection. On multivariate analysis, preoperative external beam radiation therapy (EBRT) (OR 4.29, 95% CI 1.06-17.40, P = 0.042) and skin graft placement (OR 6.39, 95% CI 1.37-29.84, P = 0.018) were found to be independent predictors of MWCs. MWC occurrence did not predict for chronic toxicity and did not impact tumor control or survival.

CONCLUSIONS

A considerable proportion of MWCs occur >120 days from surgical resection with preoperative EBRT and skin graft placement independent predictors for MWCs. While an additional source of morbidity, MWC occurrence did not impact tumor control, nor did it predict for chronic toxicity. J. Surg. Oncol. 2016;114:385-391. © 2016 Wiley Periodicals, Inc.

Pioneering technique using Acellular Dermal Matrix in the rescue of a radiation ulcer

BACKGROUND

Radiotherapy as an adjuvant to mastectomy is integral to the treatment of breast cancer, but can result in skin ulceration. Skin ulceration following radiotherapy is traditionally managed by removing the implant and allowing the skin to heal by secondary intention.

CASE REPORT

A 42-year-old woman underwent radiotherapy following a breast reconstruction. She developed a 2 x 3cm radiation ulcer. The ulcer was managed by removing the implant and performing capsulectomy. A Beckers 50 expander was placed and reinforced with acellular dermal matrix inferolaterally. At follow-up the patient had a good cosmetic outcome.

CONCLUSION

Post-radiation skin ulcers present a challenge to treat with no current standardised management. The use of acellular dermal matrix may present a new technique to promote healing in these testing cases.

A pilot study using the Chinese herbal paste Liu-He-Dan to manage radiodermatitis associated with breast cancer radiotherapy

BACKGROUND

During radiotherapy for breast cancer, patients are greatly affected by pain, infection, and delayed healing of wounds caused by radiodermatitis. In the present study, we aimed to determine the efficacy of Liu-He-Dan in treating radiodermatitis.

METHODS

In 26 breast cancer patients who experienced moist decrustation while receiving radiotherapy, 5 g Liu-He-Dan was applied externally once daily after the wound surface had been cleaned and dried. The healing time was recorded, and a Kaplan-Meier survival curve was applied to analyze the treatment course. Meanwhile, a pain assessment using the Numeric Rating Scale (nrs) recorded the pain level experienced by patients after application of the Liu-He-Dan.

RESULTS

After application of Liu-He-Dan, the average healing time for the surface of the moist decrustation wounds was 14.17 ± 2.03 days (range: 5-22 days). Inflammatory seepage decreased significantly and exudation almost disappeared in 3 days. The pain trend line indicated that the average nrs score declined with treatment in all patients. The average nrs scores at days 1, 4, and 7 were 6.13, 3.62, and 2.58 respectively. After 3 days of treatment, pain was remarkably alleviated in 80.76% of patients. After treatment for 1 week, the pain remission rate was 96.15%, without any obvious adverse reactions.

CONCLUSIONS

Liu-He-Dan was efficacious in treating radiation skin injury with little toxicity and few side effects; the economic efficiency of the treatment was also favourable. The Liu-He-Dan was generally well tolerated by patients. In future, randomized control trials will be established for further observation of the value of Liu-He-Dan in treating radiodermatitis in breast cancer.

Successful use of a topical mixture with ozolipoile in the treatment of actinic ulcers

Purpose

Post-radiation skin damage is the result of alterations produced in the irradiated zone. There are different studies aimed at verifying the effectiveness of several kinds of molecules in the treatment of radiation-induced skin damage. The purpose of this study is to test a mixture with a formulation containing several natural active ingredients on actinic ulcers in patients receiving radiation therapies.

Patients and methods

The authors recruited 13 patients, and randomly divided them into a test group (T₁) and a control group (T₂). The patients in both groups were undergoing radiotherapy. The T₁ group was treated with a mixture called ozolipoile, whereas the T₂ group was administered hyaluronic acid gel followed by non-ablative laser therapy. We evaluated the obtained results, the time of clinical healing, the reduction of pain, and each side effect, comparing all data between the T₁ and T₂ groups.

Results

The average Visual Analog Scale results showed decrease in pain in both groups; however, while the T₁ group showed a significant decrease in the values, the T₂ group reported a more gradual reduction in the values, without ever reaching the minimum values obtained with the treatment with ozolipoile.

Conclusion

Treatment of actinic ulcers with ozolipoile mixture leads to faster control of pain and to better healing of small-size ulcers.

Reconstruction plates used in the surgery for mandibular discontinuity defect

OBJECTIVES

The purpose of this study was to analyze the survival rate of reconstruction plates that were used to correct mandibular discontinuity defects.

MATERIALS AND METHODS

We analyzed clinical and radiological data of 36 patients. Only discontinuous mandibular defect cases were included in the study. Reconstruction plate survival rate was analyzed according to age, gender, location of defect, defect size, and whether the patient underwent a bone graft procedure, coronoidectomy, and/or postoperative radiation therapy (RT).

RESULTS

Plate-related complications developed in 8 patients, 7 of which underwent plate removal. No significant differences were found in plate survival rate according to age, gender, location of defect, defect size, or whether a bone graft procedure was performed. However, there were differences in the plate survival rate that depended on whether the patient underwent coronoidectomy or postoperative RT. In the early stages (9.25±5.10 months), plate fracture was the most common complication, but in the later stages (35.75±17.00 months), screw loosening was the most common complication.

CONCLUSION

It is important to establish the time-related risk of complications such as plate fracture or screw loosening. Coronoidectomy should be considered in most cases to prevent complications. Postoperative RT can affect the survival rate and hazard rate after a reconstruction plate is fitted.

The Effects of Adiantum capillus-veneris on Wound Healing: An Experimental In Vitro Evaluation

BACKGROUND

A lot of remedies, mostly plant based, were mentioned in the Persian old pharmacopoeias for promoting of burn and wound healing and tissue repairing. The efficacy of most of these old remedies is unexplored till now. Adiantum capillus-veneris from Adiantaceae family is one of them that was used to treating of some kinds of chronic wounds.

METHODS

Methanol extract was fractionated to four different partitions that is, hexane, ethyl acetate, n-butanol, and aqueous. The potential of A. capillus-veneris fractions in wound healing or prevention of chronic wounds were evaluated through angiogenesis and fibroblast proliferation, in addition to in vitro tests for protection against damage to fibroblasts by oxygen free radicals.

RESULTS

The aqueous part of A. capillus-veneris promoted significant angiogenesis (P < 0.05) through both capillary-like tubular formations and proliferation of endothelial cells in vitro. In addition, in the tests for protection against damage to fibroblasts by oxygen free radicals, aqueous and butanol fractions showed significant protective effects in the concentrations 50, and 500 μg/ml (P < 0.05) in comparison with a control group. In the toxicity testing, it showed weak irritation in the Hen's egg test chorioallantoic membrane (CAM) bioassay at the vascular level on the CAM of the chicken and no significant cytotoxicity in the MTT assays on normal human dermal fibroblasts.

CONCLUSIONS

Angiogenic effects and protective effects against oxygen free radicals suggested aqueous partition of A. capillus-veneris local application for prevention of late-radiation-induced injuries after radiation therapy and healing of external wounds similar to bedsores and burns.

The safety and efficacy of EGF-based cream for the prevention of radiotherapy-induced skin injury: results from a multicenter observational study

Purpose

This study was designed to evaluate the efficacy and safety of topically applied recombinant human epidermal growth factor (rhEGF) for the prevention of radiation-induced dermatitis in cancer patients.

Materials and Methods

From December 2010 to April 2012, a total of 1,172 cancer patients who received radiotherapy (RT) of more than 50 Gy were prospectively enrolled and treated with EGF-based cream. An acute skin reaction classified according to the Radiation Therapy Oncology Group 6-point rating scale was the primary end point and we also assessed the occurrence of edema, dry skin, or pruritus.

Results

The percentage of radiation dermatitis with maximum grade 0 and grade 1 was 19% and 58% at the time of 50 Gy, and it became 29% and 47% after completion of planned RT. This increment was observed only in breast cancer patients (from 18%/62% to 32%/49%). Adverse events related to the EGF-based cream developed in 49 patients (4%) with mild erythema the most common. Skin toxicity grade >2 was observed in 5% of the patients. Edema, dry skin, and pruritus grade ≥3 developed in 9%, 9%, and 1% of the patients, respectively.

Conclusion

Prophylactic use of an EGF-based cream is effective in preventing radiation dermatitis with tolerable toxicity. Further studies comparing EGF cream with other topical agents may be necessary.

Finger injury from over-exposure to an industrial gamma radiation source

The aim of this paper was to report a rare cause of radionecrosis and its long-term results. Iridium-192 ((192)Ir) is commonly used for radiography as a gamma ray source to locate flaws in welds and metal components in gas and oil industry. A 38-year-old man was subjected to radiation unintentionally. One month after the exposure wounds were appeared on the second and third fingers, and they were treated by conventional wound care and hyperbaric oxygen therapy. However wounds were relapsed one year later that brought the patient to us. The wounds were treated by wound care and hyperbaric oxygen therapy. When the patient was brought to us one year later the result was interesting. The third finger's pulp (there was not any wound one year before) was contracted and one third of the distal phalanx was exposed.

Can tissue spectrophotometry and laser Doppler flowmetry help to identify patients at risk for wound healing disorders after neck dissection?

OBJECTIVE

Microcirculation and oxygen supply in cervical skin were measured with an optical, noninvasive method in patients with or without radiotherapy before neck dissection. The course of wound healing was monitored after the surgical procedure to identify predictive factors for postoperative wound healing disorders.

STUDY DESIGN

Tissue spectrophotometry and laser Doppler flowmetry were used to determine capillary oxygen saturation, hemoglobin concentration, blood flow, and blood velocity at 2-mm and 8-mm depths in the cervical skin of 91 patients before neck dissection in a maxillofacial unit of a university hospital in Munich, Germany. Parameters were evaluated for differences between patients with irradiation (24) and without (67) and patients with wound healing disorders (25) and without (66) (univariate or multivariate statistical analyses).

RESULTS

Velocity at 2 mm was lower in irradiated skin (P = .016). Flow at 2 mm was higher in patients with wound healing disorders (P = .018).

CONCLUSIONS

High flow values could help to identify patients at risk for cervical wound healing disorders.

Promotion of wound healing using adipose-derived stem cells in radiation ulcer of a rat model

Background

Wound healing is a complex biologic process that involves the integration of inflammation, mitosis, angiogenesis, synthesis, and remodeling of the extracellular matrix. However, some wounds fail to heal properly and become chronic. Although some simulated chronic wound models have been established, an efficient approach to treat chronic wounds in animal models has not been determined. The aim of this study was to develop a modified rat model simulating the chronic wounds caused by clinical radiation ulcers and examine the treatment of chronic wounds with adipose-derived stem cells.

Results

Sprague–Dawley rats were irradiated with an electron beam, and wounds were created. The rats received treatment with adipose-derived stem cells (ASCs), and a wound-healing assay was performed. The wound sizes after ASC treatment for 3 weeks were significantly smaller compared with the control condition (p < 0.01). Histological observations of the wound edge and immunoblot analysis of the re-epithelialization region both indicated that the treatment with ASCs was associated with the development of new blood vessels. Cell-tracking experiments showed that ASCs were colocalized with endothelial cell markers in ulcerated tissues.

Conclusions

We established a modified rat model of radiation-induced wounds and demonstrated that ASCs accelerate wound-healing.