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1.
J Craniofac Surg ; 2024 Sep 13.
Article de Anglais | MEDLINE | ID: mdl-39265187

RÉSUMÉ

Positional plagiocephaly is a craniofacial condition resulting from infant positioning that applies pressure consistently to a part of the skull. This study analyzed the prevalence of, and costs associated with orthotic helmet treatment for positional plagiocephaly and assessed inequities in treatment between medically underserved areas (MUAs) and non-MUAs using health insurance claims data from the Center for Health Information and Analysis (CHIA) in Massachusetts for the years 2016-2021. The mean percentage of patients receiving orthotic helmet therapy was 4.3% (SD=0.49, 95% CI=3.88-4.91, P=0.44). MUAs contained 37.2% of patients with positional plagiocephaly and 2.9% of MUA patients were treated with helmets compared with 5.2% of non-MUA patients (P<0.01). There was a significant decline in the percentage of patients prescribed helmeting therapy over the course of the study (P<0.01). The average copay amount for public insurance was $0.00, and for private insurance, it was $559.8 (SD=160.7, 95% CI=529.1-590.5, P<0.01). Of 3295 claims for orthotic helmet treatment, 92 were fully denied (2.8%). Private insurers issued more fully denied claims (3.8%) than public insurance (1.1%) (P<0.01). We found that public insurance is favorable for patients seeking treatment due to a lower likelihood of full denial and lower copayments. In addition, we found that there is a significant disparity in the prevalence of helmet treatment in MUAs, and the percentage of patients treated with helmeting therapy has declined over time.

2.
Ann Plast Surg ; 92(4S Suppl 2): S204-S206, 2024 Apr 01.
Article de Anglais | MEDLINE | ID: mdl-38556674

RÉSUMÉ

INTRODUCTION: The American Academy of Pediatrics Back-to-Sleep Campaign significantly reduced infant mortality from sudden infant death syndrome. As a result of prolonged supine positioning, the incidence of deformational plagiocephaly has also risen 5-fold since its adoption. We aimed to improve the current educational paradigm for new parents with the goal of reducing the incidence of plagiocephaly within the confines of the Back-to-Sleep Campaign. We hypothesized that the early addition of plagiocephaly focused education for parents would reduce cephalic index, the ratio of head width to length, used as an easily measured objective proxy for positional plagiocephaly. METHODS: Children were screened at their newborn visit. Premature newborns and those diagnosed with craniofacial disorders were excluded. For those enrolled, biparietal and anteroposterior measurements of the head were obtained using manual calipers to obtain cephalic index. Subjects randomly assigned to the intervention group were shown a 2-minute video and given an educational pamphlet on methods to prevent plagiocephaly. Unpaired 2-sample t tests comparing mean differences in intervention and control were performed. RESULTS: Thirty-nine subjects were enrolled as of November 2023 with variable lengths of follow-up completed. The average baseline cephalic index for subjects in the control group was 82.7 and 83.8 for intervention group. Unpaired 2-sample t tests were performed at 2-, 4-, and 6-month time points to analyze the difference between groups. At 4 months, average cephalic index for subjects in the control and treatment group, respectively, was 90.6 and 83.4 (P = 0.02). SIGNIFICANCE: Parental education at the newborn visit led to decreases in cephalic index, a proxy for positional plagiocephaly, compared with control patients. This simple intervention has the potential to reduce parental stress and healthcare costs associated with the evaluation and treatment of plagiocephaly.


Sujet(s)
Plagiocéphalie positionnelle , Plagiocéphalie , Nourrisson , Humains , Nouveau-né , Enfant , Plagiocéphalie positionnelle/prévention et contrôle , Plagiocéphalie positionnelle/diagnostic , Décubitus dorsal , Plagiocéphalie/prévention et contrôle , Plagiocéphalie/complications , Parents , Sommeil
3.
Ann Plast Surg ; 92(4S Suppl 2): S123-S128, 2024 Apr 01.
Article de Anglais | MEDLINE | ID: mdl-38319984

RÉSUMÉ

BACKGROUND: Burns traditionally require frequent, painful dressing changes to minimize infection risk and promote wound healing. To improve care for our pediatric population, our institution adapted a skin graft donor site dressing into a "stick-down" burn dressing consisting of a one-time application of bacitracin and 3% bismuth tribromophenate/vaseline impregnated gauze (Xeroform) that adheres to the burn and peels off as new epithelialized skin forms. The goal of which is to minimize dressing change frequency and patient discomfort in a cost-effective, widely available manner. This study aimed to compare clinical outcomes of the stick-down versus traditional topical dressings. METHODS: A retrospective cohort study of pediatric patients (age <18 year) with partial-thickness burns treated at a level I pediatric trauma center for 4 years was conducted. One hundred eleven patients were included: 74 patients treated with daily silver sulfadiazene (Silvadene) dressings matched to 37 patients treated with the Xeroform stick-down dressing using 2:1 propensity score matching. Univariate analyses used Wilcoxon rank sum and Fisher exact tests. RESULTS: The cohorts had similar demographics and burn characteristics. Both groups had similar hospitalization rates (31.1% Silvadene, 32.4% Xeroform), most commonly for pain control (54.5% Silvadene, 58.3% Xeroform), with similar average daily narcotic usage (7.7 ± 12.1 morphine milliequivalents Silvadene, 5.1 ± 9.5 Xeroform; P = 0.91). The Xeroform cohort had a shorter but statistically similar hospital stay (median, 1 vs 2 days). In addition, the Xeroform cohort required significantly less dressing changes with a median of 0.5 changes compared with 12 for the Silvadene cohort ( P < 0.0001). There was no difference in time to burn reepithelialization (median, 13.0 days for Silvadene and 12.0 days for Xeroform; P = 0.20) or wound healing complications (12.5% Silvadene, 2.7% Xeroform; P = 0.15). CONCLUSIONS: The Xeroform stick-down dressing has equivalent clinical outcomes to that of standard Silvadene dressings for the treatment of pediatric partial-thickness burns with the major advantages of decreasing dressing change frequency, minimizing patient distress and pain, and streamlining clinical care.


Sujet(s)
Brûlures , Phénols , Traumatismes des tissus mous , Humains , Enfant , Adolescent , Sulfadiazine d'argent , Études rétrospectives , Bandages , Infection de plaie opératoire , Brûlures/thérapie , Douleur
4.
Plast Reconstr Surg ; 147(6): 1369-1376, 2021 Jun 01.
Article de Anglais | MEDLINE | ID: mdl-33973960

RÉSUMÉ

BACKGROUND: Cephalic index, the ratio of head width to length, is one normative indicator used by insurers to derive criteria for plagiocephaly helmet authorization. Current norms were established by a small sample of white children in the 1987 Farkas and Munro data set. This study establishes updated cephalic index values for infants and children in a large, diverse patient population. METHODS: Children aged 0 to 3 months, 3 to 6 months, 9 to 12 months, 2 to 3 years, and 12 to 14 years were recruited at their well-child appointment. Cephalic index was calculated for each age group and compared to previously established norms. RESULTS: Eight hundred seventy patients met inclusion criteria. The means for boys and girls between 0 and 6 months were 83.5 (n = 155, SD 6.01) and 83.5 (n = 191, SD 5.80), respectively. Established means for boys and girls between 0 and 6 months were 74.4 (n = 38, SD 5.2) and 74.3 (n = 49, SD 6.1), respectively. The difference between norms is highly statistically significant (p < 0.0001). For this age range, insurance criteria for a helmet is >83.7 for boys and >82.7 for girls. Using previous norms, 74 boys (44.6 percent) and 104 girls (54.5 percent) would meet criteria for a helmet under current guidelines. CONCLUSIONS: The mean cephalic index of children has changed. The reasons could include diversifying populations in the United States and the introduction of the Back to Sleep campaign. Over 50 percent of children may inappropriately meet criteria for a helmet based on prior norms. Updating norms could change the definition of plagiocephaly for a helmet orthosis.


Sujet(s)
Poids et mesures du corps/méthodes , Dispositifs de protection de la tête , Tête/anatomie et histologie , Orthèses , Plagiocéphalie/physiopathologie , Plagiocéphalie/thérapie , Adolescent , Enfant , Enfant d'âge préscolaire , Études transversales , Femelle , Volontaires sains , Humains , Nourrisson , Nouveau-né , Mâle , Normes de référence
5.
J Burn Care Res ; 42(4): 825-828, 2021 08 04.
Article de Anglais | MEDLINE | ID: mdl-33914874

RÉSUMÉ

Burn depth is a critical factor in determining the healing potential of a burn as the extent of injury ultimately guides overall treatment. Visible-Light Hyperspectral Imaging is an FDA-approved, noninvasive, and noncontrast imaging technology that uses light waves within the visible spectrum to evaluate skin and superficial soft tissue perfusion. In this case report, visible-light hyperspectral imaging was used to evaluate a 37-year-old male who presented to the Emergency Department with a thermal burn of the trunk, back, and right upper extremity. Images were taken at initial evaluation, 6 hours postinjury, and again during daily dressing changes until hospital day 5 when the patient underwent surgical debridement. In this patient, operative treatment was postponed until 89.7 hours postinjury, at which point the clinical examination showed clear visual demarcation in regions of irreversible damage. Comparatively, visible-light hyperspectral imaging analysis of the permanently injured tissue demonstrated acute but varying changes in both oxygenated hemoglobin and deoxygenated hemoglobin at the time of initial evaluation. The most dramatic change in tissue oxygenation occurred between 6.5 and 39.3 hours, demonstrating visible-light hyperspectral imaging's ability to detect significant differences in oxygenation values between areas of second-degree superficial burns and areas of second-degree deep and third-degree burns in the acute period. The data suggest that the utilization of visible-light hyperspectral imaging in this 6.5- to 39.3-hour window may help predict final burn depth before clinical assessment, potentially allowing for surgical intervention within the first 48 hours following injury.


Sujet(s)
Brûlures/imagerie diagnostique , Brûlures/anatomopathologie , Imagerie hyperspectrale/méthodes , Peau/vascularisation , Adulte , Brûlures/physiopathologie , Humains , Mâle , Cicatrisation de plaie
7.
Plast Reconstr Surg ; 145(1): 103-112, 2020 01.
Article de Anglais | MEDLINE | ID: mdl-31577660

RÉSUMÉ

BACKGROUND: Fat grafting is an adjuvant that may improve the quality of radiation-damaged tissue. However, fat grafting for volume restoration in irradiated sites may be less effective because of a poorly vascularized fibrotic recipient bed. External volume expansion has emerged as a potential technique to prepare the recipient sites for improved survival of grafted fat. The authors previously demonstrated increased vasculature with external volume expansion stimulation of irradiated tissues. The authors now hypothesize that external volume expansion's improvements in recipient-site vascularity will increase the volume retention and quality of fat grafts in fibrotic irradiated sites. METHODS: Athymic mice were irradiated until development of chronic radiation injury. Then, the irradiated site was stimulated by external volume expansion (external volume expansion group), followed by subcutaneous fat grafting. Grafts in an irradiated site without external volume expansion stimulation (irradiated control group) and grafts in a healthy nonirradiated (nonirradiated control group) site were used as controls. All grafts were monitored for 8 weeks and evaluated both histologically and by micro-computed tomography for analysis of volume retention. RESULTS: Hyperspectral imaging confirmed a 25 percent decrease in vascularity of irradiated tissue (irradiated control group) compared with nonirradiated tissue (nonirradiated control group). Grafts in the irradiated control group retained 11 percent less volume than grafts in the nonirradiated control group. The experimental external volume expansion group achieved a 20 percent (p = 0.01) increase in retained graft volume compared with the irradiated control group. CONCLUSIONS: External volume expansion stimulation can mitigate the effects of irradiation at the recipient site and in turn help preserve fat graft volume retention. Possible mechanisms include increased vascularity, adipogenic conversion, and increased compliance of a fibrotic recipient site.


Sujet(s)
Lésions radiques expérimentales/chirurgie , Graisse sous-cutanée/transplantation , Expansion tissulaire/méthodes , Animaux , Modèles animaux de maladie humaine , Souris , Microtomographie aux rayons X
8.
Tissue Eng Part A ; 25(11-12): 842-854, 2019 06.
Article de Anglais | MEDLINE | ID: mdl-30306830

RÉSUMÉ

IMPACT STATEMENT: This research describes the use of human mesenchymal progenitor cells for generating functional adipose tissue in vivo in a nude mouse model. Further preclinical development of the methods and insights described in this article can lead to therapeutic use of these cells in regenerative and reconstructive medicine.


Sujet(s)
Adipocytes/métabolisme , Tissu adipeux/métabolisme , Différenciation cellulaire , Transplantation de cellules souches mésenchymateuses , Cellules souches mésenchymateuses/métabolisme , Adipocytes/cytologie , Tissu adipeux/cytologie , Animaux , Hétérogreffes , Humains , Mâle , Cellules souches mésenchymateuses/cytologie , Souris , Souris nude
9.
Arch Plast Surg ; 44(5): 361-369, 2017 Sep.
Article de Anglais | MEDLINE | ID: mdl-28946716

RÉSUMÉ

As the popularity of fat grafting research increases, animal models are being used as the source of pre-clinical experimental information for discovery and to enhance techniques. To date, animal models used in this research have not been compared to provide a standardized model. We analyzed publications from 1968-2015 to compare published accounts of animal models in fat grafting research. Data collected included: species used, graft characteristics (donor tissue, recipient area, amount injected, injection technique), time of sacrifice and quantification methods. Mice were most commonly used (56% of studies), with the "athymic nude" strain utilized most frequently (44%). Autologous fat was the most common source of grafted tissue (52%). Subcutaneous dorsum was the most common recipient site (51%). On average, 0.80±0.60 mL of fat was grafted. A single bolus technique was used in 57% of studies. Fat volume assessment was typically completed at the end of the study, occurring at less than 1 week to one year. Graft volume was quantified by weight (63%), usually in conjunction with another analysis. The results demonstrate the current heterogeneity of animal models in this research. We propose that the research community reach a consensus to allow better comparison of techniques and results. One example is the model used in our laboratory and others; this model is described in detail. Eventually, larger animal models may better translate to the human condition but, given increased financial costs and animal facility capability, should be explored when data obtained from small animal studies is exhausted or inconclusive.

10.
Plast Reconstr Surg ; 139(6): 1285e-1290e, 2017 Jun.
Article de Anglais | MEDLINE | ID: mdl-28538567

RÉSUMÉ

BACKGROUND: Necrosis remains a significant complication in cutaneous flap procedures. Monitoring, and ideally prediction, of vascular compromise in the early postoperative period may allow surgeons to limit the impact of complications by prompt intervention. Hyperspectral imaging could be a reliable, effective, and noninvasive method for predicting flap survival postoperatively. In this preclinical study, the authors demonstrate that hyperspectral imaging is able to correlate early skin perfusion changes and ultimate flap survival in a preclinical model. METHODS: Thirty-one hairless, immunocompetent, adult male mice were used. Random pattern dorsal skin flaps were elevated and sutured back into place with a silicone barrier. Hyperspectral imaging and digital images were obtained 30 minutes, 24 hours, or 72 hours after flap elevation and before sacrifice on postoperative day 7. RESULTS: Areas of high deoxygenated hemoglobin change (124; 95 percent CI, 118 to 129) seen at 30 minutes after surgery were associated with greater than 50 percent flap necrosis at postoperative day 7. Areas demarcated by high deoxygenated hemoglobin at 30 minutes postoperatively had a statistically significant correlation with areas of macroscopic necrosis on postoperative day 7. Analysis of images obtained at 24 and 72 hours did not show similar changes. CONCLUSIONS: These findings suggest that early changes in deoxygenated hemoglobin seen with hyperspectral imaging may predict the region and extent of flap necrosis. Further clinical studies are needed to determine whether hyperspectral imaging is applicable to the clinical setting.


Sujet(s)
Imagerie diagnostique/méthodes , Rejet du greffon/anatomopathologie , Transplantation de peau/méthodes , Lambeaux chirurgicaux/anatomopathologie , Lambeaux chirurgicaux/transplantation , Animaux , Modèles animaux de maladie humaine , Rejet du greffon/épidémiologie , Survie du greffon , Mâle , Souris , Souris hairless , Nécrose/imagerie diagnostique , Nécrose/anatomopathologie , Valeur prédictive des tests , Répartition aléatoire , Appréciation des risques , Transplantation de peau/effets indésirables , Transillumination
11.
Cleft Palate Craniofac J ; 54(5): 535-539, 2017 09.
Article de Anglais | MEDLINE | ID: mdl-27427933

RÉSUMÉ

OBJECTIVE: Reconstructive surgical care can play a vital role in the resource-poor settings of low- and middle-income countries. Telemedicine platforms can improve the efficiency and effectiveness of surgical care. The purpose of this study is to determine whether remote digital video evaluations are reliable in the context of a short-term plastic surgical intervention. SETTING: The setting for this study was a district hospital located in Latacunga, Ecuador. PATIENTS: Participants were 27 consecutive patients who presented for operative repair of cleft lip and palate. MAIN OUTCOME MEASURES: We calculated kappa coefficients for reliability between in-person and remote digital video assessments for the classification of cleft lip and palate between two separate craniofacial surgeons. We hypothesized that the technology would be a reliable method of preoperative assessment for cleft disease. RESULTS: Of the 27 (81.4%) participants, 22 received operative treatment for their cleft disorder. Mean age was 11.1 ± 8.3 years. Patients presented with a spectrum of disorders, including cleft lip (24 of 27, 88.9%), cleft palate (19 of 27, 70.4%), and alveolar cleft (19 of 27, 70.4%). We found a 95.7% agreement between observers for cleft lip with substantial reliability (κ = .78, P < .01). There was an 82.6% agreement between observers for cleft palate, with a moderate interrater reliability (κ = .55, P = .01). We found only a 47.8% agreement between observers for alveolar cleft with a nonsignificant, weak kappa agreement (κ = .06, P = .74). CONCLUSIONS: Remote digital assessments are a reliable way to preoperatively diagnose cleft lip and palate in the context of short-term plastic surgical interventions in low- and middle-income countries. Future work will evaluate the potential for real-time, telemedicine assessments to reduce cost and improve clinical effectiveness in global plastic surgery.


Sujet(s)
Bec-de-lièvre/chirurgie , Fente palatine/chirurgie , /méthodes , Consultation à distance/méthodes , Adolescent , Adulte , Enfant , Enfant d'âge préscolaire , Équateur , Femelle , Humains , Nourrisson , Mâle , Études rétrospectives , Résultat thérapeutique
13.
Clin Transl Radiat Oncol ; 4: 15-23, 2017 Jun.
Article de Anglais | MEDLINE | ID: mdl-29594203

RÉSUMÉ

INTRODUCTION: Radiation therapy is crucial to effective cancer treatment. Modern treatment strategies have reduced possible skin injury, but few clinical studies have addressed the dose relationship between radiation exposure and skin reaction. This prospective clinical study analyzes skin oxygenation/perfusion in patients undergoing fractionated breast conserving therapy via hyperspectral imaging (HSI). METHODS: Forty-three women undergoing breast conserving therapy were enrolled in this study. Optically stimulated luminescent dosimeters (OSLDs) measured radiation exposure in four sites: treatment breast, lumpectomy scar, medial tattoo and the control breast. The oxygenation/perfusion states of these sites were prospectively imaged before and after each treatment fraction with HSI. Visual skin reactions were classified according to the RTOG system. RESULTS: 2753 observations were obtained and indicated a dose-response relationship between radiation exposure and oxygenated hemoglobin (OxyHb) after a 600 cGy cumulative dose threshold. There was a relatively weak association between DeoxyHb and radiation exposure. Results suggest strong correlations between changes in mean OxyHb and skin reaction as well as between radiation exposure and changes in skin reaction. CONCLUSION: HSI demonstrates promise in the assessment of skin dose as well as an objective measure of skin reaction. The ability to easily identify adverse skin reactions and to modify the treatment plan may circumvent the need for detrimental treatment breaks.

16.
Plast Reconstr Surg ; 137(5): 799e-807e, 2016 May.
Article de Anglais | MEDLINE | ID: mdl-27119942

RÉSUMÉ

BACKGROUND: External volume expansion prepares recipient sites to improve outcomes of fat grafting. For patients receiving radiotherapy after mastectomy, results with external volume expansion vary, and the relationship between radiotherapy and expansion remains unexplored. Thus, the authors developed a new translational model to investigate the effects in chronic skin fibrosis after radiation exposure. METHODS: Twenty-four SKH1-E mice received 50 Gy of ß-radiation to each flank and were monitored until fibrosis developed (8 weeks). External volume expansion was then applied at -25 mmHg to one side for 6 hours for 5 days. The opposite side served as the control. Perfusion changes were assessed with hyperspectral imaging. Mice were euthanized at 5 (n = 12) and 15 days (n = 12) after the last expansion application. Tissue samples were analyzed with immunohistochemistry for CD31 and Ki67, Masson trichrome for skin thickness, and picrosirius red to analyze collagen composition. RESULTS: All animals developed skin fibrosis 8 weeks after radiotherapy and became hypoperfused based on hyperspectral imaging. Expansion induced edema on treated sides after stimulation. Perfusion was decreased by 13 percent on the expansion side (p < 0.001) compared with the control side for 5 days after stimulation. Perfusion returned to control-side levels by day 15. Dermal vasculature increased 38 percent by day 15 (p < 0.01) in expansion versus control. No difference was found in collagen composition. CONCLUSIONS: External volume expansion temporarily reduces perfusion, likely because of transient ischemia or edema. Together with mechanotransduction, these effects encourage a proangiogenic and proliferative environment in fibrotic tissue after radiotherapy in the authors' mouse model. Further studies are needed to assess these changes in fat graft retention.


Sujet(s)
Particules bêta/effets indésirables , Modèles animaux de maladie humaine , Lésions radiques expérimentales/thérapie , Radiodermite/thérapie , Expansion tissulaire , Tissu adipeux/transplantation , Animaux , Collagène/analyse , Oedème/étiologie , Oedème/thérapie , Femelle , Fibrose , Humains , Mammoplastie , Souris , Souris hairless , Traitement des plaies par pression négative , Néovascularisation physiologique , Oxygène/sang , Peau/vascularisation , Peau/composition chimique , Peau/effets des radiations , Ulcère cutané/étiologie , Ulcère cutané/thérapie , Expansion tissulaire/méthodes , Expanseurs tissulaires
17.
Plast Reconstr Surg ; 137(1): 122-131, 2016 Jan.
Article de Anglais | MEDLINE | ID: mdl-26710016

RÉSUMÉ

BACKGROUND: External volume expansion by suction is used to prepare the recipient site for fat grafting by increasing its compliance and vascularity. The authors previously developed a mouse model for external volume expansion and demonstrated its pro-proliferative and angiogenic effects. Increased thickness of the subcutaneous tissue was also observed. This study was thus designed to assess the adipogenic potential of external volume expansion stimulation. METHODS: A miniaturized external volume expansion device consisting of a rubber dome connected to a -25 mmHg suction source was applied to the dorsum of mice for a single 2-hour stimulation or for 2 hours daily for 5 days. Tissues were harvested up to 48 hours after the last stimulation and analyzed for edema, inflammation, and adipocyte content by staining for hematoxylin and eosin, CD45, and perilipin-A. Expression of peroxisome proliferator-activated receptor-γ (proadipogenic factor) and preadipocyte factor 1 (preadipocyte marker) was evaluated by Western blot analysis. RESULTS: Both a 2-hour stimulation and cyclical 2-hour stimulation for 5 days induced 1.5- and 1.9-fold increases in the number of adipocytes per millimeter. Edema was present in the immediate poststimulation period, and inflammation was seen 2 days later. Peroxisome proliferator-activated receptor-γ was increased at the end of stimulation. CONCLUSIONS: Stretch is known to stimulate proliferation, whereas edema and inflammation are both emerging proadipogenic factors. Their combination in external volume expansion seems to produce proadipogenic effects, seen even after a single 2-hour stimulation.


Sujet(s)
Adipocytes/cytologie , Adipogenèse/physiologie , Expanseurs tissulaires , Expansion tissulaire/méthodes , Adipocytes/physiologie , Animaux , Technique de Western , Prolifération cellulaire/physiologie , Mâle , Souris , Souris hairless , Modèles animaux , Répartition aléatoire , Sensibilité et spécificité , Graisse sous-cutanée/métabolisme , Expansion tissulaire/instrumentation
18.
Front Oncol ; 5: 232, 2015.
Article de Anglais | MEDLINE | ID: mdl-26579490

RÉSUMÉ

BACKGROUND: Radiation exposure can lead to detrimental effects in skin microcirculation. The precise relationship between radiation dose received and its effect on cutaneous perfusion still remains controversial. Previously, we have shown that hyperspectral imaging (HSI) is able to demonstrate long-term reductions in cutaneous perfusion secondary to chronic microvascular injury. This study characterizes the changes in skin microcirculation in response to varying doses of ionizing radiation and investigates these microcirculatory changes as a possible early non-invasive biomarker that may correlate with the extent of long-term microvascular damage. METHODS: Immunocompetent hairless mice (n = 66) were exposed to single fractions of superficial beta-irradiation in doses of 0, 5, 10, 20, 35, or 50 Gy. A HSI device was utilized to measure deoxygenated hemoglobin levels in irradiated and control areas. HSI measurements were performed at baseline before radiation exposure and for the first 3 days post-irradiation. Maximum macroscopic skin reactions were graded, and histological assessment of cutaneous microvascular densities at 4 weeks post-irradiation was performed in harvested tissue by CD31 immunohistochemistry. RESULTS: CD31 immunohistochemistry demonstrated a significant correlation (r = 0.90, p < 0.0001) between dose and vessel density reduction at 4 weeks. Using HSI analysis, early changes in deoxygenated hemoglobin levels were observed during the first 3 days post-irradiation in all groups. These deoxygenated hemoglobin changes varied proportionally with dose (r = 0.98, p < 0.0001) and skin reactions (r = 0.98, p < 0.0001). There was a highly significant correlation (r = 0.91, p < 0.0001) between these early changes in deoxygenated hemoglobin and late vascular injury severity assessed at the end of 4 weeks. CONCLUSION: Radiation dose is directly correlated with cutaneous microvascular injury severity at 4 weeks in our model. Early post-exposure measurement of cutaneous deoxygenated hemoglobin levels may be a useful biomarker for radiation dose reconstruction and predictor for chronic microvascular injury.

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