Background: As a fibrotic disease with a high incidence, the pathogenesis of hypertrophic scarring is still not fully understood, and the treatment of this disease is also challenging. In recent years, human adipose-derived mesenchymal stem cells (AD-MSCs) have been considered an effective treatment for hypertrophic scars. This study mainly explored whether the therapeutic effect of AD-MSCs on hypertrophic scars is associated with oxidative-stress-related proteins. Methods: AD-MSCs were isolated from adipose tissues and characterized through flow cytometry and a differentiation test. Afterwards, coculture, cell proliferation, apoptosis, and migration were detected. Western blotting and a quantitative real-time polymerase chain reaction (qRT–PCR) were used to detect oxidative stress-related genes and protein expression in hypertrophic scar fibroblasts (HSFs). Flow cytometry was used to detect reactive oxygen species (ROS). A nude mouse animal model was established; the effect of AD-MSCs on hypertrophic scars was observed; and hematoxylin and eosin staining, Masson’s staining, and immunofluorescence staining were performed. Furthermore, the content of oxidative-stress-related proteins, including nuclear factor erythroid-2-related factor 2 (Nrf2), heme oxygenase 1 (HO-1), B-cell lymphoma 2(Bcl2), Bcl2-associated X(BAX) and caspase 3, was detected. Results: Our results showed that AD-MSCs inhibited HSFs’ proliferation and migration and promoted apoptosis. Moreover, after coculture, the expression of antioxidant enzymes, including HO-1, in HSFs decreased; the content of reactive oxygen species increased; and the expression of Nrf2 decreased significantly. In animal experiments, we found that, at 14 days after injection of AD-MSCs into human hypertrophic scar tissue blocks that were transplanted onto the dorsum of nude mice, the weight of the tissue blocks decreased significantly. Hematoxylin and eosin staining and Masson’s staining demonstrated a rearrangement of collagen fibers. We also found that Nrf2 and antioxidant enzymes decreased significantly, while apoptotic cells increased after AD-MSC treatment. Conclusions: Our results demonstrated that AD-MSCs efficiently cured hypertrophic scars by promoting the apoptosis of HSFs and by inhibiting their proliferation and migration, which may be related to the inhibition of Nrf2 expression in HSFs, suggesting that AD-MSCs may provide an alternative therapeutic approach for the treatment of hypertrophic scars.

Background: An ideal 3D cartilage framework and accurate anatomical location are the most important factors to carry out a satisfactory reconstruction of the ear. To streamline this process, we developed an augmented reality assistance system, HoloLens Ear Image Guidance, which is based on computed tomography (CT) data, tailor-made navigation kits to guide reconstruction, data processing software, and HoloLens hardware. The objective of this study is to verify its feasibility in a clinical setting. Methods: This study first validated our system in healthy controls and then extrapolated data to test on patients with microtia. First, three healthy volunteers were recruited, and reconstructive navigation kits were made using 3D printing. CT data were collected for the head and neck and imported into the HoloLens Ear Image Guidance Application to generate a personalized 3D virtual ear image. Volunteers then wore the navigation kits while researchers observed them through the HoloLens to check accuracy, track delay, and view the ear image guide. Ten patients with unilateral microtia were recruited and CT data were collected, and reconstructive navigation kits were made to assist with surgery. The procedure was monitored to record the surgeon's experience wearing the HoloLens, the patients' complications associated with wearing navigation kit, and to measure the symmetry between the reconstructed ear and the reference counterpart. Results: In control patients, the deviation between the virtual image and the real ear was less than 2.4% (±0.22%); the tracking delay was less than 1.26 s (±0.09 s), the display effect was good, and surgeons did not report discomfort or dizziness while wearing the HoloLens. Volunteers did not report any pain from holding the navigation reference in their mouth during the test. Following validation, the HoloLens-assisted procedures were not associated with surgeon discomfort or dizziness. No complications were noted in patients including injury to the oral mucosa. Symmetry between the reconstructed ear and the contralateral ear was noted to be satisfactory in HoloLens-assisted surgery. Conclusions: The HoloLens Ear Image Guidance initially met clinical demands in registration accuracy, tracking speed, and subjective user experience, which can be used as the basis for continual software improvements and clinical application.

Postburn auricular reconstruction presents significant challenges due to scar contracture and compromised vascularity of the surrounding tissue. This study introduces and evaluates a specialized 3-stage surgical protocol that integrates expanded scarred skin with residual cartilage and a custom-shaped autologous costal cartilage framework. A retrospective case series was conducted on 21 patients with postburn ear defects treated between January 2021 and 2024. The surgical approach involved 3 stages: (1) subcutaneous implantation of a tissue expander to release scar contractures and expand residual tissue; (2) formation of a composite flap using the expanded scarred skin and mobilized residual cartilage to envelop a custom-sculpted framework carved from selected costal cartilages; and (3) refinement of anatomic subunits. Aesthetic outcomes were assessed by independent plastic surgeons using a 4-point Likert scale, and patient-reported satisfaction and quality of life were evaluated with the EAR-Q questionnaire. The mean follow-up duration was 21.93±16.01 months. Aesthetic evaluations yielded high satisfaction, with most cases rated as “Excellent” (n=7, 33.3%) or “Good” (n=13, 61.9%). Patient-reported outcomes through the EAR-Q demonstrated high mean scores in the “Psychological” (63.00, IQR=55.50–89.00) and “Social” (64.00, IQR=6.00–85.50) domains. A strong positive correlation was observed between psychological adjustment and social functioning (τ=0.670, P <0.001). No patients reported dissatisfaction or major complications. By integrating residual cartilage into the expanded flap, this technique effectively addresses the challenges of compromised vascularity and scar contracture, resulting in improved auricular symmetry and projection, as well as significant psychosocial benefits for patients.