Chronic Pain Following Breast Reconstruction: A Scoping Review.

BACKGROUND: Breast cancer survival rates have increased significantly, underscoring the importance of enhancing long-term health-related quality of life. Breast reconstruction following mastectomy has emerged as a common approach that contributes to improved health-related quality of life. Nonetheless, chronic pain following breast reconstruction is a prevalent issue that has a negative impact on overall well-being. METHODS: To examine recent findings on chronic pain after breast reconstruction and progress in pain management, we performed a review of the literature through independent searches using the MEDLINE database within NIH National Library of Medicine PubMed. RESULTS: The review suggested that autologous reconstruction causes chronic postsurgical pain, especially at specific donor sites, whereas implant-based reconstruction does not seem to increase the risk of chronic pain. Moreover, certain operational and patient factors are also associated with chronic pain. Appropriate pain management can reduce chronic pain and prevent the transition from acute to chronic pain. CONCLUSION: This scoping review evaluated the characteristics of long-term chronic pain after breast reconstruction. The findings provide patients with important treatment information and will assist with their decision on their preferred treatment.

[Multidirectional Cranial Distraction Osteogenesis for Craniosynostosis].

In this article we explain in detail the Multidirectional Cranial Distraction Osteogenesis(MCDO)procedure for treating craniosynostosis, in which the multiple cranial bone flaps are pulled up in different directions by the external distractor with the helmet-type frame. MCDO has several advantages over conventional procedures such as unilateral cranial distraction osteogenesis(UCDO). First, the design of the osteotomy in MCDO is flexible depending on the deformities. Each bone flap can be moved to the desired direction in MCDO, while being moved only in one direction along the axis of the distractor in UCDO. This enables remodeling of the deformed cranium to the desired shape. Second, compared with UCDO, the distance between each bone flap after distraction is narrower in MCDO, allowing earlier bone formation and fusion, and thus a shorter consolidation period. Third, the expansion efficacy of MCDO is greater than that of UCDO. The maximum defects of MCDO were the large amount of osteotomy and the resulting heavy bleeding. Therefore, we have recently attempted to improve the design and procedure of osteotomy. The MCDO method allows all phenotypes of skull deformity to be reshaped by distraction osteogenesis.

Transcription factor scleraxis vitally contributes to progenitor lineage direction in wound healing of adult tendon in mice.

Tendon is a dense connective tissue that transmits high mechanical forces from skeletal muscle to bone. The transcription factor scleraxis (Scx) is a highly specific marker of both precursor and mature tendon cells (tenocytes). Mice lacking scx exhibit a specific and virtually complete loss of tendons during development. However, the functional contribution of Scx to wound healing in adult tendon has not yet been fully characterized. Here, using ScxGFP-tracking and loss-of-function systems, we show in an adult mouse model of Achilles tendon injury that paratenon cells, representing a stem cell antigen-1 (Sca-1)-positive and Scx-negative progenitor subpopulation, display Scx induction, migrate to the wound site, and produce extracellular matrix (ECM) to bridge the defect, whereas resident tenocytes exhibit a delayed response. Scx induction in the progenitors is initiated by transforming growth factor ß (TGF-ß) signaling. scx-deficient mice had migration of Sca-1-positive progenitor cell to the lesion site but impaired ECM assembly to bridge the defect. Mechanistically, scx-null progenitors displayed higher chondrogenic potential with up-regulation of SRY-box 9 (Sox9) coactivator PPAR-γ coactivator-1α (PGC-1α) in vitro, and knock-in analysis revealed that forced expression of full-length scx significantly inhibited Sox9 expression. Accordingly, scx-null wounds formed cartilage-like tissues that developed ectopic ossification. Our findings indicate a critical role of Scx in a progenitor-cell lineage in wound healing of adult mouse tendon. These progenitor cells could represent targets in strategies to facilitate tendon repair. We propose that this lineage-regulatory mechanism in tissue progenitors could apply to a broader set of tissues or biological systems in the body.

Development of Multidirectional Cranial Distraction Osteogenesis for the Treatment of Craniosynostosis.

BACKGROUND: Previously, the authors developed a new method of distraction osteogenesis for the treatment of craniosynostosis, multidirectional cranial distraction osteogenesis (MCDO). The purpose of this study is to review the authors' experience of MCDO for remodeling of the anterior cranium in the patients of craniosynostosis. METHODS: Forty-five patients with craniosynostosis underwent MCDO for anterior cranial remodeling from 2003 to 2017. The ages of the patients ranged from 8 to 72 months (mean: 23.9 months, median: 13 months). The involved sutures included the bicoronal suture in 14 patients, unicoronal suture in 4 patients, sagittal suture in 14 patients, metopic suture in 2 patient, and multiple sutures in 10 patients. RESULTS: An improvement of in cranial shape was achieved in 40 patients. In 1 patient, intraoperative massive bleeding forced us finishing the procedure before completing the planned osteotomy. Transient cerebrospinal fluid leakage occurred in 3 patients during the activation phase but recovered with conservative therapy. The mean blood transfusion was 25.5 mL/kg. The phase of activation ranged from 7 to 17 days (mean, 10.6 days) and the consolidation period ranged from 16 to 67 days (mean, 32.4 days). Loosening of traction pins occurred in 7 patients, resulting in undercorrection in 2 patients, and loosening of anchor pins occurred in 19 patients, resulting in acceleration of removal of the devices in 7 patients. CONCLUSIONS: Multidirectional cranial distraction osteogenesis was effective and has several advantages over the conventional procedures. Therefore, the authors conclude that MCDO will be a useful alternative for all phenotypes of craniosynostosis.

Mandibular Reconstruction Based on the Concept of Double Arc Reconstruction.

The natural mandible has 2 arcs, the marginal arc and the occlusal arc. The marginal arc is situated along the lower margin of the mandible and affects the contour of the lower third of the face. The occlusal arc is situated along the dental arc and affects the stability of prosthodontics. The gap between these 2 arcs widens in the molar area. Our developed concept of "double arc reconstruction" involves making these 2 arcs for the reconstructed mandible. For the double-barrel fibula reconstruction, 2 bone segments are used to make both arcs. For reconstructions using the iliac crest, the double arc is made by inclination of the top of the bone graft toward the lingual side. Ten patients underwent double arc reconstruction: 2 underwent reconstruction with the double-barrel fibula, and 8 underwent reconstruction with the iliac crest. Four patients had a removable denture prosthesis, 1 had an osseointegrated dental implant, and 5 did not require further prosthodontic treatment. The shape of the reconstructed mandible after double arc reconstruction resembles the native mandible, and masticatory function is good with the use of a dental implant or removable denture prosthesis, or even without prosthodontics.

Shaping of the Unaffected Breast with Brava-Assisted Autologous Fat Grafting to Obtain Symmetry after Breast Reconstruction.

BACKGROUND: In breast reconstruction, symmetry is a vital issue. However, when the original breast is unusually shaped or the patient desires augmentation at the time of reconstruction, obtaining symmetrical breasts becomes difficult. OBJECTIVES: The authors performed shaping of unaffected breasts by Brava-assisted autologous fat grafting to enhance breast symmetry, and evaluated the clinical results to validate this new approach. METHODS: Brava-assisted autologous fat grafting was performed to the unaffected breasts of 12 patients who had undergone unilateral breast reconstruction. The procedure was used for augmentation in six patients and to correct ptosis, volume, and tuberous breast deformity in three, two, and one patient, respectively. Clinical outcomes were assessed in all 12 patients. RESULTS: All patients could complete fat grafting within two sessions (one session in nine patients and two sessions in three patients). The mean volume of grafted fat per session was 211 cc in all patients. The mean retention rate of grafted fat was 58.9% in the 10 patients for whom the retention rate could be calculated using preoperative and postoperative magnetic resonance imaging (MRI). Postoperative MRI revealed small benign foci in two patients (16.7%), which were not palpable and did not become a clinical problem. A postoperative mammography revealed a small agglutinate calcification in one patient, which was determined to be benign through biopsy. CONCLUSIONS: Shaping the unaffected breast by autologous fat grafting combined with Brava is predictable, effective, and feasible as an aesthetic adjunct to unilateral breast reconstruction to achieve breast symmetry. LEVEL OF EVIDENCE: 4 Therapeutic.

A novel surgical correction using a combination of wave-like incision and Z-axis Z-plasty for congenital constriction band syndrome.

BACKGROUND: A congenital constriction band (CCB) is a relatively common anomaly among limb malformations. However, the number of cases treated at a given center is limited and differences in techniques used by surgeons at each facility have a significant impact on the treatment outcomes. Several surgical methods have been reported, but a standard technique that yields consistent satisfactory results is still needed. Here, we introduce a novel technique for the treatment of CCB syndrome that uses a combination of wave-like skin incision and Z-axis Z-plasty. PATIENTS AND METHODS: A wave-like incision was used for skin incision with the goals of achieving an accordion effect and a less noticeable post-operative scar. After the fibrous constriction band was completely excised, a Z-plasty of sufficient size in the Z-axis direction was performed on the dermis-inclusive adipose tissue. For over 10 years, this technique was applied to 11 sites in 6 patients. A retrospective study of the characteristics of these cases was performed, including age at surgery, gender, type of deformity, degree of constriction, types of examination, number of surgeries, and post-operative outcomes. RESULTS: In all patients, a normal contour of the limbs was achieved and the hourglass-like deformity caused by the constriction band was satisfactorily improved. No additional corrective surgeries were needed, there was no abnormal growth of the treated limbs, and scarring was aesthetically acceptable in all cases. CONCLUSION: The novel technique described here uses deep subcutaneous fat to correct the hourglass-like deformity and restores a normal limb contour, while the wave-like skin incision minimizes post-operative scarring.

Micronized cellular adipose matrix purified with a bladed connector contains abundant functional adipose stem cells.

INTRODUCTION: A specialized device equipped with a sharp blade filter has been developed to enable more efficient purification of a micronized cellular adipose matrix (MCAM) containing stem cells. The aim of this study is to compare the characteristics and functions of the population of stromal cells (mSVF) and cultured cells (mASCs) purified using this device with those of cSVF and cASCs obtained through conventional enzymatic purification. METHODS: Cell viability, proliferation capacity and yield were assessed. Characterization of stem cell potency was performed by analyzing cell surface markers including CD34, a marker of activated adipose-derived stem cells. The trilineage differentiation potential was evaluated using RT-PCR and histology. RESULTS: The yield rate of mSVF obtained from MCAM was significantly higher than that with the conventional method, although use of the device resulted in a slight decrease in cell viability. After culture, mASCs exhibited a remarkable clonogenic potential and significantly higher cell proliferation potential than cASCs. The mASCs also displayed a distinct pattern of ASC cell surface markers, increased expression of genes related to CD34, high pluripotency, and a high trilineage differentiation ability. CONCLUSION: The specialized device enhanced the yield of SVF and produced cells with high proliferation rates and characteristics that include expression of stem cell markers.

An Effective Approach to Collecting Lymph Vessels Using a Small Diameter Wire for Lymphaticovenous Anastomosis in Upper Limb Lymphedema.

Lymphaticovenous anastomosis (LVA), which involves connecting lymphatic vessels to veins under a microscope, is widely performed around the world as a surgical treatment for lymphedema due to its relatively low patient burden and consistent efficacy. One of the crucial points of LVA is identifying suitable lymphatic vessels from among many lymphatic vessels and connecting them at the most effective site, but in practice, this is not easy to do. To overcome this issue, we have been able to effectively drain lymph by connecting lymphatic vessels to veins just before the occluded site using a lymphatic wire that was just recently developed in Japan. The device guides the subcutaneous deep collecting lymphatic vessels from the peripheral relatively superficial lymphatic vessels. While this special wire is typically adapted in the lower limbs, we have confirmed its effectiveness in upper limb lymphedema as well. Overall, this approach shows promise for improving the accuracy and success rates of LVA procedures, which can have significant benefits for patients with upper limb lymphedema. In this article, we share our experience using lymphatic wire for upper limb lymphedema cases.

Irradiation affects adipose-derived stem cells and wound healing depending on radiation dose and frequency.

BACKGROUND: Radiation therapies are often associated with permanent devitalization in the surrounding tissue. We hypothesized that stem cells are damaged depending on each irradiation dose and frequency of fractionated radiotherapies, which results in impaired tissue function including wound healing capacity. METHODS: To test the hypothesis, susceptibility of human adipose-derived stem cells (ASCs) to a single irradiation (0-10 Gy) was assessed in vitro. In vivo chronic radiation effects were also assessed on the mouse dorsal skin (N=4-5) for 6 months after a total of 40 Gy irradiation (0 Gy as control) using one of three fractionated protocols (2 Gy daily for 20 days, 10 Gy weekly for 4 weeks, or 10 Gy monthly for 4 months). Oxygen partial pressure, oxygen saturation of hemoglobin, and dorsal skin viscoelasticity were periodically measured, and wound healing and tissue immunohistology were compared at 6 months. RESULTS: A single irradiation of cultured human ASCs resulted in a dose-dependent increase in cell death up to 2 Gy but with no further increases between 2 and 10 Gy. Most of the apoptotic ASCs were in the proliferation phase. Among the three in vivo irradiation protocols, the 2 Gy×20 group had the most severe chronic tissue damage (i.e., skin dysfunction, subcutaneous atrophy, and depletion of CD34+ stem cells) 6 months after the irradiation. Wound healing was also impaired most significantly in the 2 Gy×20 group. CONCLUSIONS: These results have important clinical implications for surgeons and radiotherapists such as the timing of surgical interventions and the optimization of fractionation protocols.Clinical Relevance Statement: Irradiation damages stem cells depending on the radiation dose and frequency. Using the ultimately optimized protocol, we can minimize the long-term functional deficits of radiated tissue without losing anti-cancer efficacy of radiation therapy.

Asystole Due to Oculocardiac Reflex during Surgical Repair of an Orbital Blowout Fracture.

Bradycardia and asystole due to oculocardiac reflex (OCR) are potential intraoperative complications of periocular surgery. We report a case of asystole due to OCR that occurred during surgical repair performed 40 hours after an orbital blowout fracture. The patient had vomiting, bradycardia, and ocular motility disorder before the operation. During the operation, asystole occurred when the entrapped tissue was grasped with forceps. After administration of anticholinergic drugs, the heart promptly resumed beating, and no sequelae due to asystole were observed after surgery. Before and during periocular surgery, it is important for the surgeon to maintain a protective surgical procedure and communicate appropriately with the anesthesiologist, including discussion of risks and emergency measures. In addition, prolonged entrapment of the extraocular muscles is likely to cause irreversible damage, so it is important to make a diagnosis and perform surgery as soon as possible.

Multi-directional Cranial Distraction Osteogenesis for Treating Sagittal Synostosis with Frontometaphyseal Dysplasia: A Case Report.

Frontometaphyseal dysplasia (FMD), also known as Gorlin-Cohen syndrome, is a rare genetic syndrome. This syndrome affects the skeletal system and connective tissue, and causes a wide spectrum of manifestations of the skull, tubular bones, cardiovascular system, urinary system, and/or gastrointestinal system. Craniofacial findings of FMD are characterized by protruding supraorbital ridge, broad nasal bridge, hypertelorism, down-slanting palpebral fissures, and/or micrognathia. We describe a case of a 2-year-old girl diagnosed with sagittal synostosis accompanied with FMD. She presents anterior sagittal synostosis cranial form, compressed cerebrospinal fluid space (which suggested increased intracranial pressure), and the supraorbital hyperostosis. She underwent multi-directional cranial distraction osteogenesis in the calvaria and shaving of the supraorbital ridges. Despite concerns about bone fragility associated with FMD, the surgery was accomplished as usual. The patient had no intra- and postoperative complications. After 6 months of follow-up, the cranial shape has improved and the cerebrospinal fluid space has widened, but the supraorbital ridge has protruded again. Re-protrusion of the supraorbital ridge appears to be due to age-appropriate vigorous osteogenesis. The multi-directional cranial distraction osteogenesis procedure has been useful for treating sagittal synostosis even concomitant with FMD.

The Effects of Ischemia and Hyperoxygenation on Hair Growth and Cycle.

Alopecia has several causes, but its relationship with ischemia/hypoxia has not yet been investigated in detail. In this study, we studied the changes of hair follicles induced by ischemia and potential effects of normobaric hyperoxygenation (NBO) on the hair cycle and growth. We found that skin ischemia reduced hair growth rate, hair shaft size, and its pigmentation in the anagen phase of mice, which may reflect an aspect of pathophysiology of hair loss (alopecia) and depigmentation (gray/white hairs). Hyperoxygenation increased hair growth rate in organ culture of both human and murine hair follicles. Systemic NBO promoted hair growth in early anagen and mid-anagen, and delayed catagen onset in mice. However, telogen-to-anagen transition was not affected by NBO as far as non-ischemic skin is concerned. The results of this study indicated that the hair follicle is very sensitive to oxygen tension and oxygen tension affects the regulation of hair growth and cycle in vitro and in vivo. It was suggested that systemic NBO can be safely applied for a long period and can be a noninvasive therapeutic approach to alter hair growth and cycle by manipulating the microenvironment of hair follicles.

Hair Regeneration Potential of Human Dermal Sheath Cells Cultured Under Physiological Oxygen.

We investigated the effect of oxygen tension on the proliferation and hair-inductive capacity of human dermal papilla cells (DPCs) and dermal sheath cells (DSCs). DPCs and DSCs were separately obtained from human hair follicles and each cultured under atmospheric/hyperoxic (20% O2), physiological/normoxic (6% O2), or hypoxic (1% O2) conditions. Proliferation of DPCs and DSCs was highest under normoxia. Compared with hyperoxia, hypoxia inhibited proliferation of DPCs, but enhanced that of DSCs. In DPCs, hypoxia downregulated the expression of hair-inductive capacity-related genes, including BMP4, LEF1, SOX2, and VCAN. In DSCs, both normoxia and hypoxia upregulated SOX2 expression, whereas hypoxia downregulated BMP4 expression. Microarray analysis revealed that normoxia increased the expression of pluripotency-related genes, including SPRY, NR0B1, MSX2, IFITM1, and DAZL, compared with hyperoxia. In an in vivo hair follicle reconstitution assay, cultured DPCs and DSCs were transplanted with newborn mouse epidermal keratinocytes into nude mice using a chamber method. In this experiment, normoxia resulted in the most efficient induction of DPC hair follicles, whereas hypoxia caused the most efficient induction and maturation of DSC hair follicles. These results suggest that application of physiological/hypoxic oxygen tension to cultured human DSCs enhances proliferation and maintenance of hair inductivity for skin engineering and clinical applications. Impact statement Dermal sheath cells (DSCs) and dermal papilla cells (DPCs) are useful cell sources for cell-based regenerative therapy. This is the first report to describe that low-oxygen conditions are better for DSCs. Normoxic and hypoxic culture of DSCs is beneficial for expanding these hair follicular cells and advancing development of cell-based therapy for both wound healing and hair regeneration. The current study supports that optimized oxygen tension can be applied to use expanded human DPCs and DSCs for skin engineering and clinical applications.

Multidirectional cranial distraction osteogenesis technique for treating bicoronal synostosis.

Fronto-orbital advancement by distraction osteogenesis is a useful means of surgically correcting bicoronal synostosis. However, the scope for morphological revision is limited. To address this issue, we developed a multidirectional cranial distraction osteogenesis (MCDO) technique that we quantitatively assessed in patients with bicoronal synostosis. In this case series, five patients with bicoronal synostosis were treated with MCDO at a mean age of 13.4 months (range 9-22 months). Distraction started 5 days after surgery and the activation period was 11.2 days (range 10-14 days). The distraction devices were removed 47.2 days (range 33-67 days) after completing distraction. Improved cranial shape was confirmed by CT data. Mean preoperative CI, APL, and ICV readings of 102.1%, 13.5 cm, and 1179.4 ml, respectively, had reached 94.0%, 14.9 cm, and 1323.9 ml, respectively, upon device removal. These values were well preserved at 1 year (90.4%, 15.8 cm, and 1461.3 ml, respectively). In conclusion, MCDO successfully enables both cranial expansion and correction of a flat forehead, constituting a valid treatment alternative for patients with bicoronal synostosis.

Contact Dermatitis Caused by Dermabond Advanced Use.

BACKGROUND: Dermabond Advanced (DBA) has been widely used globally; however, severe contact dermatitis (CD) can be a serious adverse effect of DBA use. In this study, we investigated the characterization and incidence rate of CD after using DBA and the safe use of DBA. METHODS: One hundred consecutive patients who underwent skin closure with DBA were investigated. All patients were women undergoing breast reconstruction. DBA was applied to their trunk and limbs following reconstruction. RESULTS: Seven patients (7%) presented with CD. Of these, 4 patients exhibited CD after the second DBA use; sensitization influence by the first DBA use was considered. One of 3 patients presenting with CD after the first DBA use was allergic to cosmetic glue, and the influence of immunological cross-reaction of acrylates was suggested. CONCLUSION: We consider that DBA use is inadequate for wounds with an improper margin and in dry and low-skin barrier areas such as the trunk and limbs because it may induce irritant CD and sensitization of DBA and subsequent allergic CD. Frequent use can also induce sensitization. If patients have a history of acrylate allergies, DBA use should be avoided because immunological cross-reaction from acetylates could result.

Tumoral Calcinosis: A Giant Tumoral Mass in the Shoulder Joint of a Dialysis Patient.

Tumoral calcinosis is a rare condition in which a calcified mass grows around a large joint, and can occur in patients undergoing renal dialysis. Here, we report the case of a 64-year-old man with a long history of dialysis who presented with a giant, painless mass in his right shoulder joint. A near-complete surgical resection is performed without muscle function loss and with no sign of recurrence after 1 year.

Biological Properties and Therapeutic Value of Cryopreserved Fat Tissue.

BACKGROUND: Fat grafting frequently requires multiple treatments and thus repeated liposuction to achieve treatment goals. The purpose of this study was to evaluate whether cryopreservation of adipose tissue may facilitate future fat grafting. METHODS: Lipoaspirates were harvested from six women and preserved using two cryopreservation methods: (1) simple cooling to -80°C (cryo-1); or (2) programmed cooling to -196°C (cryo-2). Fresh fat, cryo-1 fat, and cryo-2 fat were analyzed both in vitro and in vivo. RESULTS: Immunohistochemistry of both types of cryopreserved adipose tissue revealed that most adipocytes were necrotic. The cell number and viability of stromal vascular fraction cells were significantly decreased in cryo-1 fat (1.7 × 10 cells, 42.6 percent viable) and cryo-2 fat (2.0 × 10 cells, 55.4 percent viable), compared with fresh fat (3.9 × 10 cells, 90.6 percent viable). Although adipose-derived stem cells were cultured successfully from all fats, functional adipose-derived stem cells from cryopreserved fats were much fewer, with comparable multilineage differentiating capacity. In vivo studies using human fat grafted into immunocompromised mice revealed that, 3 months after transplantation, all of the cryopreserved fats maintained their volume to some extent; however, the cryopreserved fats were mostly filled with dead tissue and produced significantly lower engraftment scores than fresh fat. CONCLUSIONS: Most adipocytes were killed in the process of cryopreservation and thawing. Adipose-derived stem cells were isolated from cryopreserved fat, but the number of functional adipose-derived stem cells was very limited in both cryopreservation methods. After grafting, cryopreserved fat was retained as dead and fibrous tissue, suggesting a risk of clinical complications such as oil cysts.

Therapeutic effects of a recombinant human collagen peptide bioscaffold with human adipose-derived stem cells on impaired wound healing after radiotherapy.

Chronic changes following radiotherapy include alterations in tissue-resident stem cells and vasculatures, which can lead to impaired wound healing. In this study, novel recombinant human collagen peptide (rhCP) scaffolds were evaluated as a biomaterial carrier for cellular regenerative therapy. Human adipose-derived stem cells (hASCs) were successfully cultured on rhCP scaffolds. By hASC culture on rhCP, microarray assay indicated that expression of genes related to cell proliferation and extracellular matrix production was upregulated. Pathway analyses revealed that signaling pathways related to inflammatory suppression and cell growth promotion were activated as well as signaling pathways consistent with some growth factors including vascular endothelial growth factor, hepatocyte growth factor, and transforming growth factor beta, although gene expression of these growth factors was not upregulated. These findings suggest the rhCP scaffold showed similar biological actions to cytokines regulating cell growth and immunity. In subsequent impaired wound healing experiments using a locally irradiated (20 Gray) mouse, wound treatment with rhCP sponges combined with cultured hASCs and human umbilical vein endothelial cells accelerated wound closure compared with wounds treated with rhCP with hASCs alone, rhCP only, and control (dressing alone), with better healing observed according to this order. These results indicating the therapeutic value of rhCP scaffolds as a topical biomaterial dressing and a biocarrier of stem cells and vascular endothelial cells for regenerating therapies. The combination of rhCP and functional cells was suggested to be a potential tool for revitalizing stem cell-depleted conditions such as radiation tissue damage.

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.