RESUMO
Nipple sparing mastectomy (NSM) has become an accepted approach in selected cases of breast cancer and prophylactic mastectomy. Various surgical techniques have been described and nipple ischemia has been a common complication. Potential risk factors for nipple ischemia after NSM are examined. To examine predisposing factors for nipple ischemia after NSM. Prospective evaluation of 71 consecutive NSM in 45 patients from 2009 to 2011 was performed. There were 40 mastectomies for cancer (56.3%), and 31 (43.7%) prophylactic mastectomies. In cases of cancer, the ducts were excised from the undersurface of the nipple. Reconstructive methods included: expander 58, latissimus flap/expander 2, implant 10, and free TRAM flap 1. Various patient and technical factors were examined for impact on nipple ischemia. Partial nipple necrosis occurred in 20 cases (28.2%). Nineteen cases healed uneventfully and one required secondary nipple reconstruction. Operations for cancer (OR 10.54, CI 1.88-59.04, p = 0.007) and periareolar incisions (OR 9.69, CI 1.57-59.77, p = 0.014) predisposed to nipple ischemia. Periareolar incisions and dissection of the nipple ducts for cancer have a higher risk of nipple necrosis after NSM.
Assuntos
Neoplasias da Mama/cirurgia , Isquemia/etiologia , Mastectomia Subcutânea/efeitos adversos , Mastectomia Subcutânea/métodos , Mamilos/irrigação sanguínea , Adulto , Carcinoma Intraductal não Infiltrante/cirurgia , Estudos de Coortes , Feminino , Humanos , Mamoplastia/métodos , Pessoa de Meia-Idade , Estudos Prospectivos , Retalhos Cirúrgicos , Resultado do TratamentoRESUMO
BACKGROUND: Autologous fat transfer is a common procedure; however, results are variable and unpredictable. OBJECTIVES: Stem cell responses to hypoxic environments need to be elucidated to determine which cell types contribute to graft survival. METHODS: Acellular dermal matrix (ADM) envelopes were implanted in the subcutaneous tissues of 4 swine. In each swine, 2 envelopes were inserted as controls (ADM group), and 2 were placed and injected with 5 mL of autologous fat (ADM/fat group). Two additional envelopes were inserted and filled with 5 mL of fat and an omental pedicle (A/F/O group). Animals were sacrificed and the envelopes excised at 1, 2, 4, and 16 weeks. Specimens were analyzed histologically and/or with flow cytometry. RESULTS: Fat was retained in ADM envelopes with and without a pedicle blood supply, although the percentage of volume retention was greater in the pedicled group. The peak number of mesenchymal progenitor cells within the ADM/fat group was significantly greater than the peak in the A/F/O group (P =.044), whereas endothelial progenitor cells in the ADM/fat group showed a prolonged increase through 4 weeks (P =.015 vs the A/F/O group at week 4). At 16 weeks, the interior surface of the matrix in the ADM/fat group had significantly more blood vessels than that of the ADM or A/F/O group (P = .0021 and .0036, respectively). CONCLUSIONS: Injecting fat into hypoxic environments significantly increases the mesenchymal and endothelial progenitor cell responses and enhances the formation of blood vessels.
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Derme Acelular , Tecido Adiposo/transplante , Microambiente Celular , Técnicas Cosméticas , Células Progenitoras Endoteliais/transplante , Transplante de Células-Tronco Mesenquimais , Tecido Adiposo/citologia , Tecido Adiposo/metabolismo , Animais , Hipóxia Celular , Linhagem da Célula , Células Progenitoras Endoteliais/metabolismo , Feminino , Células-Tronco Mesenquimais/metabolismo , Neovascularização Fisiológica , Sus scrofa , Fatores de Tempo , Transplante AutólogoRESUMO
Background: Two-stage tissue expander to implant surgery remains the predominant technique for breast reconstruction. Unfortunately, there is a high incidence of reconstruction failure which portends a financial and emotional burden. Most failures are related to postmastectomy skin flap necrosis and infection. Recently, a dual-port tissue expander was introduced to the market, and the authors hypothesize that early cultures from the peri-implant fluid will guide antibiotic treatment and decrease reconstruction failure. Methods: This is a cohort study of 50 consecutive patients treated for breast cancer or genetic susceptibility via a two-stage, prepectoral technique. The first 25 patients (46 breasts) were treated with a variety of tissue expanders, and the subsequent 25 patients (47 breasts) received a dual-port expander. Routine cultures from the drain port were taken from the dual-port group at the second postoperative visit, and cultures were taken in the control group only when signs of infection were present. All other procedures and interventions were similar. Results: Fifty patients, totaling 93 breasts, completed the study with a mean follow-up of 145 days. There were no statistically significant demographic or pathologic differences between groups. Fifteen tissue expanders were explanted in the control group and five in the dual-port cohort (32.6% versus 10.6%, P = 0.012). All bacteria in the control group failures were either methicillin-resistant Staphylococcus aureus or Staphylococcus epidermidis, whereas failures in the dual-port group varied. Conclusion: Treatment of routine, early cultures from a dual-port expander led to a statistically significant decrease in tissue expander explantation.
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INTRODUCTION: Nipple-sparing mastectomy (NSM) is increasingly used to improve the results of immediate breast reconstruction. Technical aspects and aesthetic outcomes of this procedure are examined. METHODS: A study of a prospective institutional database of all cases of NSM between 2009 and 2010 was performed. Aesthetic outcomes (symmetry, inframammary fold, volume, contour, and nipple) are compared with patients undergoing skin-sparing mastectomy and immediate breast reconstruction by grading postoperative photographs. Technical refinements in incision types and nipple positioning are described. RESULTS: Twenty-six patients underwent 40 NSMs during the study period. Partial nipple necrosis occurred in 15 breasts (37.5%); of them, 14 healed uneventfully with local wound care, and 1 patient required delayed nipple reconstruction. Nipple necrosis by incision type was radial/circumareolar in 6 of 8 (75%) patients; radial, 3 of 9 (33.3%); inframammary fold, 6 of 22 (27.3%); and vertical, 0 of 1 (0%). The nipple aesthetic outcome was significantly better for NSM compared with nipple reconstruction after skin-sparing mastectomy (P = 0.01). CONCLUSIONS: The incidence of partial nipple necrosis was high and was related to circumareolar incisions. Most cases of nipple necrosis are superficial and heal uneventfully. Preservation of the nipple improves the aesthetic outcome of immediate breast reconstruction.
Assuntos
Neoplasias da Mama/cirurgia , Mastectomia Subcutânea/métodos , Mamilos/cirurgia , Adulto , Estética , Feminino , Humanos , Pessoa de Meia-Idade , Necrose/epidemiologia , Necrose/etiologia , Mamilos/patologia , Variações Dependentes do Observador , Complicações Pós-Operatórias/epidemiologia , Estudos Retrospectivos , Resultado do TratamentoRESUMO
BACKGROUND: Overt infection and biofilm formation resulting from breast augmentation are rare but serious problems that can lead to contracture and a need for revision surgery. The Keller Funnel is a medical device composed of a rip-stop nylon sleeve with a hydrophilic inner coating. One claim of the funnel is that it facilitates a "no touch" technique, thereby limiting contamination. To date, there are no data to support this claim. OBJECTIVES: The authors evaluate skin and breast parenchyma contamination with standard implantation techniques and the Keller funnel. METHODS: Insertion techniques were tested in two fresh cadavers. Smooth, round, moderate-plus silicone gel implants were placed for each experiment. To quantify the amount of skin contamination, a 2% w/v fluorescein paste was painted onto the cadaver thorax. After implantation, the implants were soaked in 250 mL of sterile water, and the fluorescence emission of the resulting solution was measured with an ultraviolet-visible spectrophotometer. To qualify the potential contamination from breast parenchyma, the cadaver breast tissue was swabbed with methicillin-sensitive Staphylococcus aureus, and the implant surfaces were cultured postimplantation. RESULTS: The funnel resulted in a 27-fold decrease in skin contact for all smooth gel implants (P = .00059). The amount of skin contact and potential contamination increased incrementally with increasing implant volume when either the funnel or digital implantation techniques were used. Bacterial contamination from breast parenchyma was two times more likely with the standard digital insertion technique (P = .06). CONCLUSIONS: The Keller funnel appears to significantly reduce the amount of skin contact and potential parenchyma contamination.
Assuntos
Implante Mamário/efeitos adversos , Implante Mamário/métodos , Implantes de Mama/efeitos adversos , Mama/cirurgia , Procedimentos Cirúrgicos Dermatológicos , Infecções Relacionadas à Prótese/prevenção & controle , Géis de Silicone , Mama/microbiologia , Implante Mamário/instrumentação , Implantes de Mama/microbiologia , Cadáver , Desenho de Equipamento , Feminino , Humanos , Teste de Materiais , Staphylococcus aureus Resistente à Meticilina/isolamento & purificação , Desenho de Prótese , Infecções Relacionadas à Prótese/microbiologia , Pele/microbiologia , Espectrofotometria Ultravioleta , Equipamentos CirúrgicosRESUMO
UNLABELLED:  Background. Outcomes following burn injury have improved considerably in recent years due to early excision and skin grafting. Despite a reduction in late burn complications, up to 70% of patients experience long-term pain at both the injured area and the skin-grafted scar. Current therapies do not ameliorate these symptoms for a majority of these patients. This report presents initial results of a new technique using a bilayer dermal substitute (Integra™, [Integra LifeSciences, Plainsboro, NJ]) for revision of painful scars. METHODS: This is a prospective cohort of six patients treated at Grady Memorial Hospital Burn Center (Atlanta, GA) from 2008 to 2009. Burn patients undergoing multi-modality pain therapy for chronic, painful burns were identified and consented for intervention. All patients underwent operative excision of the painful scar and placement of a bilayer dermal matrix (Integra). After 3 weeks the silicone mesh was removed, excessive granulation tissue was debrided, and a new split-thickness skin graft was placed on the wound. Prescription history and a patient questionnaire were used to collect data. RESULTS: All patients noticed improvement of symptoms post-operatively. Two patients (33%) experienced complete reduction of scar pain and three (50%) discontinued consumption of pain medications. At a mean follow up of 13 months, the average amount of narcotic-based pain medications decreased from 63.3 MED ([morphine equivalent per day], range: 30-135) before treatment to 7.5 MED (range: 0-20) postoperatively (P < 0.05). CONCLUSION: Scar excision, interval placement of a bilayer dermal matrix, and subsequent skin grafting is a new technique that can improve, and in some cases ameliorate, burn scar related pain. .
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BACKGROUND: Autologous fat is the ideal soft-tissue filler; however, its widespread application is limited because of variable clinical results and poor survival. Engineered fillers have the potential to maximize survival. Alginate is a hydrogel copolymer that can be engineered into spheres of <200 µm, thus facilitating mass transfer, allowing for subcutaneous injection, and protecting cells from shearing forces. METHODS: Alginate powder was dissolved in saline, and adipose-derived stem cells (ADSCs) were encapsulated (1 million cells/mL) in alginate using an electrostatic bead generator. To assess effects of injection on cell viability, microspheres containing ADSCs were separated into 2 groups: the control group was decanted into culture wells and the injection group was mixed with basal media and injected through a 21-gauge needle into culture wells. Microbeads were cultured for 3 weeks, and cell number and viability were measured weekly using electron and confocal microscopy. To assess effects of percutaneous injection in vivo, twenty-four male nude mice were randomly separated into 2 groups and injected with either empty microcapsules or ADSC-laden microcapsules. Mice were harvested at 1 and 3 months, and the implants were examined microscopically to assess bead and cell viability. RESULTS: A flow rate of 5 mL/h and an electrostatic potential of 7 kV produced viable ADSC-laden microbeads of <200 µm. There were no differences in bead morphology and ADSC viability between microcapsules placed versus injected into tissue culture plates for up to 3 weeks. Microspheres implanted in a nude mouse model show durability up to 3 months with a host response around each individual sphere. ADSCs remained viable and showed signs of mitosis. CONCLUSIONS: ADSCs can be readily cultured, encapsulated, and injected in alginate microspheres. Stem cells suspended in alginate microspheres survive in vivo and are seen to replicate in vitro.
Assuntos
Alginatos/farmacologia , Composição de Medicamentos/métodos , Próteses e Implantes , Transplante de Células-Tronco/métodos , Engenharia Tecidual/métodos , Tecido Adiposo/transplante , Adolescente , Animais , Sobrevivência Celular , Criança , Pré-Escolar , Estudos de Coortes , Modelos Animais de Doenças , Feminino , Seguimentos , Ácido Glucurônico/farmacologia , Ácidos Hexurônicos/farmacologia , Humanos , Implantes Experimentais , Injeções Subcutâneas , Masculino , Camundongos , Camundongos Nus , MicroesferasRESUMO
BACKGROUND: Acellular dermal matrices (ADMs) are an integral component of breast reconstruction. The ideal matrix would be relatively immuno-inert, allow rapid vascularization, and be affordable. The purpose of this study was to histologically compare 2 commonly used ADM products. METHODS: This is a prospective histological study of 17 patients (20 breasts) following prosthetic-based breast reconstruction with ADM: Alloderm (LifeCell Corp, Branchburg, N.J.) or Cortiva (RTI Surgical, Alachua Fla.). Biopsies were taken from the dermal matrix and natural capsules surrounding the expander/implant during secondary surgery [Range, 72-694 days (mean, 217 days)]. Biopsy specimens were prepared via hematoxylin and eosin, Masson's trichrome, elastin, and transforming growth factor (TGF)-1 stains. Quantitative analysis of staining was performed with ImageJ software. The clinical outcome of each patient is analyzed in relation to capsule architecture and ADM performance. RESULTS: There were 7 breasts in the Alloderm group and 13 in the Cortiva group. Both groups had similar demographic, aesthetic results, and complication profiles. The TGF-1 staining demonstrated significantly lower levels in the Cortiva capsules (P = 0.0139). The percentage of elastin and collagen are similar in the Cortiva, Alloderm, and natural peri-implant capsules. The native capsules show a significantly greater number of blood vessels when compared with Cortiva and Alloderm (P = 0.0371 and P = 0.0347, respectively); however, there is no difference in vascular pattern between the 2 dermal matrices. DISCUSSION: Postoperatively, Cortiva demonstrates equal vascularity with less TGF-1 activation compared with Alloderm. The clinical success and complication profile were similar between the Alloderm and Cortiva patients.
RESUMO
BACKGROUND: The authors compared clinical outcomes to determine whether acellular dermal matrix altered the capsular tissue architecture in irradiated and nonirradiated breasts following matrix-assisted expander reconstruction. METHODS: Part I included all 27 patients who underwent bilateral tissue expander reconstruction with acellular dermal matrix between 2007 and 2012 and subsequent unilateral radiation therapy. Part II included a subset of patients with capsular biopsy specimens taken at the time of implant exchange for histologic analysis. Specimens included irradiated and nonirradiated acellular dermal matrix and irradiated and nonirradiated native capsule. Clinical outcomes were analyzed in relation to capsule architecture and acellular dermal matrix performance. RESULTS: In part I, mean follow-up was 28 months. Grade III/IV contractures were identified in nine patients (all on the irradiated side), and 12 developed noncontracture complications (75 percent on the irradiated side). Nine patients were unable to continue with implant reconstruction and required salvage with autologous tissue. In part II, postirradiation biopsy specimens were taken of the peri-implant capsule in six patients at the time of secondary surgery. Elastin content and the total cellular infiltrate were significantly greater in the irradiated versus nonirradiated native capsules (p = 0.0015). Conversely, the irradiated matrix capsule was composed of similar amounts of cellular infiltrate and collagen as the nonirradiated matrix capsules and nonirradiated native capsules. Irradiated acellular dermal matrix showed the least amount of alpha-smooth actin staining but a similar number of blood vessels. CONCLUSION: Acellular dermal matrix appears to limit the elastosis and chronic inflammation seen in irradiated implant reconstructions and is potentially beneficial in these patients. CLINICAL QUESTION/LEVEL OF EVIDENCE: Therapeutic, III.
Assuntos
Derme Acelular/efeitos da radiação , Contratura Capsular em Implantes/etiologia , Mamoplastia/métodos , Radioterapia/efeitos adversos , Expansão de Tecido , Adulto , Feminino , Humanos , Contratura Capsular em Implantes/patologia , Pessoa de Meia-Idade , Resultado do TratamentoRESUMO
BACKGROUND: Preservation of breast skin during mastectomy has improved the cosmetic results of breast reconstruction. Unfortunately, the incidence of mastectomy skin flap necrosis remains high using conventional evaluation methods; therefore, accurate prediction of flap viability is an important component of postmastectomy reconstruction. METHODS: The authors studied a prospective cohort of women who underwent skin-sparing mastectomy and breast reconstruction over a 2-year period at Emory University. Mastectomy skin flap perfusion was measured intraoperatively using indocyanine green angiography. Once necrosis matured postoperatively, digital images were taken and superimposed over the intraoperative scan. Perfusion percentages were measured in healthy and nonviable skin. RESULTS: One hundred eighteen patients were included, and 14 patients (15 breasts) with postoperative skin necrosis and sufficient image data were analyzed. The average woman's age was 49.7 years (range, 28 to 73 years) and the average body mass index was 27.7 (range, 21.2 to 42.2). Skin with 25 percent or less perfusion (perfusion score, ≤ 25) was not viable 90 percent of the time, and areas with greater than or equal to 45 percent perfusion survived 98 percent of the time. A 33 percent perfusion score had a positive predictive value of removing nonviable skin of 88 percent and a negative predictive value of removing healthy skin of 16 percent. CONCLUSIONS: Indocyanine green angiography is a useful adjunct to assess mastectomy skin flap viability. A gray zone exists between 25 and 45 percent of maximal skin perfusion in which the ultimate viability remains in question. By designating the cutoff perfusion score of 33 percent, the surgeon can expect to more accurately remove nonviable skin. CLINICAL QUESTION/LEVEL OF EVIDENCE: Diagnostic, III.
Assuntos
Angiografia , Mama/irrigação sanguínea , Mastectomia , Pele/irrigação sanguínea , Pele/diagnóstico por imagem , Retalhos Cirúrgicos/irrigação sanguínea , Adulto , Idoso , Mama/patologia , Mama/cirurgia , Corantes , Procedimentos Cirúrgicos Dermatológicos , Feminino , Humanos , Verde de Indocianina , Mamoplastia , Pessoa de Meia-Idade , Necrose , Complicações Pós-Operatórias , Valor Preditivo dos Testes , Pele/patologia , Retalhos Cirúrgicos/patologia , Sobrevivência de TecidosRESUMO
Capsular contracture is one of the most common complications following breast surgery with implants and is a common cause for reoperation. Many techniques have been described to treat or prevent recurrent capsular contracture with varying success. Acellular dermal matrix (ADM), in combination with periprosthetic capsulectomy, is a powerful tool to delay or prevent recurrent contracture. Excellent results have been obtained when this approach has been used in patients with capsular contracture, but at increased cost.
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Implante Mamário/métodos , Mama , Colágeno , Contratura/cirurgia , Mamoplastia/métodos , Adulto , Idoso , Neoplasias da Mama/cirurgia , Contratura/etiologia , Feminino , Seguimentos , Humanos , Mastectomia , Pessoa de Meia-Idade , Pele ArtificialRESUMO
BACKGROUND: Capsular contracture has multiple causes, all of which lead to increased inflammation and scarring. There have been five generations of silicone breast implants; the most recent are filled with a highly cohesive gel thought to reduce capsular contracture. No independent data exist to support this claim. METHODS: Eight Göttingen swine were each implanted with eight 50-cc custom gel implants. In phase 1 of the study, the implant shells were photochemically altered to produce a low-bleed shell or a high-bleed shell to simulate a second-generation implant. In phase 2, both the third/fourth generation and the newest, fifth generation (highly cohesive gel) devices were implanted. Half the implants were punctured with a 3-ml punch biopsy to simulate a ruptured implant. Capsule and implant specimens were harvested at 1 and 3 months and analyzed with a Bose strain gauge. Intracapsular fluid was tested for silicon levels with atomic emission spectrometry. Histologic analysis was prepared with hematoxylin and eosin, Masson trichrome, and α-smooth muscle actin immunohistochemistry stains. RESULTS: Gel bleed correlated with capsule stiffness in a dose-dependent manner (p < 0.05). High-bleed second-generation implants had the stiffest capsules, and nonruptured third- and fourth-generation implants had the softest. Histologic examination revealed an intermediate layer of spindle-like cells staining positive for α-smooth actin in the most contracted capsules. CONCLUSIONS: There is a dose-dependant relationship between silicone gel bleed and capsule compliance that is independent of the cohesivity of the silicone. Capsule thickness and a fibrotic, α-smooth muscle actin-positive layer are present within the most contracted capsules.
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Implante Mamário/efeitos adversos , Implantes de Mama/efeitos adversos , Falha de Prótese , Géis de Silicone/efeitos adversos , Animais , Implante Mamário/métodos , Contratura/etiologia , Contratura/fisiopatologia , Modelos Animais de Doenças , Feminino , Desenho de Prótese , Distribuição Aleatória , Fatores de Risco , Ruptura Espontânea/etiologia , Ruptura Espontânea/fisiopatologia , Sensibilidade e Especificidade , Géis de Silicone/farmacologia , Sus scrofa , SuínosRESUMO
Capsular contracture remains a challenging complication of implant-based aesthetic breast surgery despite improvements in implant design. The lowering of capsular contracture rates noted with the past use of polyurethane foam-covered implants has increased awareness of the importance of the biologic response at the interface between the implant surface and breast tissue. Emerging evidence indicates that much like the polyurethane foam, acellular dermal matrices alter the biologic response at the surface interface, resulting in a more vascular and less constrictive pattern of collagen deposition. This study reports on the authors' clinical experience using Strattice Reconstructive Tissue Matrix (LifeCell Corporation, Branchburg, N.J.) for the treatment of capsular contracture in patients with established capsules and for prevention in patients undergoing primary augmentation or augmentation/mastopexy. Of 80 patients (154 breasts) in whom Strattice was used, clinically significant contracture (Baker grade III/IV) occurred in three breasts (3.75 percent), all of which were in the treatment of previous contracture group. In addition, the authors noted two seromas requiring implant removal (both patients developed capsules, as mentioned above) and two hematomas requiring revision, for an overall failure rate of 6.25 percent for Strattice-assisted surgery. The data confirm that the use of Strattice significantly lowers the incidence of capsular contracture in the first 3.5 years after implant placement.
Assuntos
Derme Acelular , Implante Mamário/métodos , Colágeno/uso terapêutico , Contratura Capsular em Implantes/prevenção & controle , Mamoplastia/métodos , Implantes de Mama , Materiais Revestidos Biocompatíveis , Colágeno/administração & dosagem , Remoção de Dispositivo , Desenho de Equipamento , Estética , Feminino , Reação a Corpo Estranho/etiologia , Reação a Corpo Estranho/patologia , Reação a Corpo Estranho/prevenção & controle , Hematoma/etiologia , Hematoma/cirurgia , Humanos , Contratura Capsular em Implantes/epidemiologia , Contratura Capsular em Implantes/patologia , Contratura Capsular em Implantes/cirurgia , Músculos Peitorais/cirurgia , Poliuretanos , Complicações Pós-Operatórias/etiologia , Complicações Pós-Operatórias/prevenção & controle , Complicações Pós-Operatórias/cirurgia , Estudos Retrospectivos , Seroma/etiologia , Seroma/cirurgia , Técnicas de Sutura , Dispositivos para Expansão de Tecidos , Falha de TratamentoRESUMO
The aim of this study was to establish a critical-sized nonjoint chondral defect animal model and to evaluate its feasibility for testing cartilage regeneration strategies. Dermal biopsy punches 1-4 mm in diameter were used to create cylindrical full-thickness defects in the center of athymic rat xiphoids. The 3 and 4 mm defects remained unhealed 35 days postsurgery, with a large area in the center that had low proteoglycan content based on contrast-enhanced microCT (EPIC-microCT), radiographic, and histological analyses. In a second step, tissue-engineered cartilage was synthesized by culturing primary bovine articular chondrocytes on poly-L-lactic acid (PLA) scaffolds in a perfusion-shear bioreactor for 28 days. These chondrocyte/PLA constructs or primary bovine chondrocytes were implanted into 3-mm-diameter defects. Empty defects and defects implanted with empty PLA scaffolds were used as controls. Xiphoids were harvested 28 days after surgery and examined with faxitron, microCT, and histology using hematoxylin and eosin and safranin-O staining. Both chondrocyte/PLA constructs and chondrocytes alone formed neocartilage. The results indicate that a 3 mm cylindrical defect in a rat xiphoid is an economic, feasible, and reproductive model to evaluate the potential of various constructs for nonjoint cartilage repair.
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Cartilagem Articular/fisiologia , Modelos Animais , Regeneração , Cicatrização , Processo Xifoide/patologia , Animais , Cartilagem Articular/diagnóstico por imagem , Cartilagem Articular/patologia , Cartilagem Articular/cirurgia , Bovinos , Glicosaminoglicanos/metabolismo , Masculino , Ratos , Microtomografia por Raio-X , Processo Xifoide/diagnóstico por imagem , Processo Xifoide/cirurgiaRESUMO
Alginate calcification has been previously reported clinically and during animal implantation; however no study has investigated the mechanism, extensively characterized the mineral, or evaluated multiple methods to regulate or eliminate mineralization. In the present study, alginate calcification was first studied in vitro: calcium-crosslinked alginate beads sequestered surrounding phosphate while forming traces of hydroxyapatite. Calcification in vivo was then examined in nude mice using alginate microbeads with and without adipose stem cells (ASCs). Variables included the delivery method, site of delivery, sex of the animal, time in vivo, crosslinking solution, and method of storage prior to delivery. Calcium-crosslinked alginate microbeads mineralized when injected subcutaneously or implanted intramuscularly after 1-6 months. More extensive analysis with histology, microCT, FTIR, XRD, and EDS showed calcium phosphate deposits throughout the microbeads with surface mineralization that closely matched hydroxyapatite found in bone. Incorporating 25 mm bisphosphonate reduced alginate calcification whereas using barium chloride eliminated mineralization. Buffering the crosslinking solution with HEPES at pH 7.3 while washing and storing samples in basal media prior to implantation also eliminated calcification in vivo. This study shows that alginate processing prior to implantation can significantly influence bulk hydroxyapatite formation and presents a method to regulate alginate calcification.
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Alginatos/metabolismo , Calcificação Fisiológica , Tecido Adiposo/citologia , Adolescente , Alginatos/química , Animais , Cálcio/metabolismo , Sobrevivência Celular , Células Cultivadas , Durapatita/metabolismo , Feminino , Ácido Glucurônico/química , Ácido Glucurônico/metabolismo , Ácidos Hexurônicos/química , Ácidos Hexurônicos/metabolismo , Humanos , Implantes Experimentais , Masculino , Camundongos , Camundongos Nus , Células-Tronco/citologia , Engenharia TecidualRESUMO
PURPOSE: To discuss the role of hyperthermia in optimizing the response to regional therapy for cancer. METHODS: A review of the current literature discussing mechanism of action, experimental models and prospective, randomized trials was performed. RESULTS: The mechanism of action of hyperthermia in combination with radiation and cytotoxic chemotherapy at the cellular and tissue levels is described. Data supporting the benefit of hyperthermia in conjunction with both regional, infusional chemotherapy, and locoregional radiation therapy is demonstrated. Several different histologic tumor types are covered, all with prospective evidence supporting the benefit of hyperthermia. CONCLUSIONS: Although delivery methods for hyperthermia can be complex and difficult to implement, the data support its benefit and further endeavors to include hyperthermia as a component of regional therapy should be encouraged.
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Quimioterapia do Câncer por Perfusão Regional/métodos , Hipertermia Induzida , Neoplasias/terapia , Animais , Ensaios Clínicos como Assunto , Terapia Combinada/métodos , Modelos Animais de Doenças , Humanos , Neoplasias/irrigação sanguínea , Radioterapia/métodosRESUMO
BACKGROUND: Breast conservation therapy is proved as efficacious as modified radical mastectomy in the treatment of early-stage breast cancer. Although cosmesis is widely considered an advantage to this approach, objective evaluations of esthetic results are sparse. STUDY DESIGN: Twenty-three patients were subjected to three-dimensional, digital imaging of their breasts using a 3dMD camera (3Q Corporation). Differences in volume and surface area were assigned an asymmetry score based on software calculations. Additional variables were queried, and results were compared with a control group of 35 age-matched patients. RESULTS: Mean asymmetry score for the control population was 3.02 and for the breast conservation therapy population was 4.59 (p = 0.001). There was a positive correlation between percentage of breast parenchyma excised and asymmetry (p = 0.036). The location of the cancer, age of the patient, and need for multiple operations did not influence cosmetic results. CONCLUSIONS: Breast conservation therapy appears to affect breast symmetry when evaluated objectively using three-dimensional imaging. In this series, the degree of asymmetry is related to the amount of tissue resected in relation to the breast volume but not on the location of the tumor, age of the patient, or need for reoperation.
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Neoplasias da Mama/cirurgia , Estética , Processamento de Imagem Assistida por Computador/instrumentação , Imageamento Tridimensional/instrumentação , Mastectomia Segmentar , Fotografação/instrumentação , Complicações Pós-Operatórias/diagnóstico , Adulto , Idoso , Idoso de 80 Anos ou mais , Neoplasias da Mama/patologia , Feminino , Seguimentos , Humanos , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Distribuição Normal , SoftwareRESUMO
BACKGROUND: The incidence of prosthetic graft infection is 1 to 6 percent, and the mortality rate of infected aortoiliac or aortofemoral bypass is 25 to 75 percent. The goal of this study was to report the use of muscle flaps in the management of patients presenting with infected vascular grafts. METHODS: A total of 22 patients required 26 muscle flaps to cover 24 infected vascular grafts. Muscle flaps were used for local wound control in all patients regardless of the fate of the graft. The vascular surgeons elected for graft salvage in eight of the 24 grafts. All of the muscle flaps survived. RESULTS: The average time interval between the bypass and infection was 371 days. One-month follow-up revealed an 88 percent salvage rate, but this decreased to 50 percent during the mean follow-up of 23 months. None of the patients originally managed with a salvaged graft lost a limb, and overall, 14 of 22 limbs in this series remained viable (64.0 percent). The mortality rate during the index hospitalization was 9 percent. In this series, suprainguinal grafts had a higher mortality rate. In addition, infection occurring more than 1 month postoperatively, culture-positive Pseudomonas and methicillin-resistant species, and exposure of the arterial-graft anastomosis were poor prognostic indicators of graft preservation. CONCLUSIONS: Management of infected vascular grafts remains a challenging problem. Muscle flap coverage should have a high priority, as the chance of a good outcome is highly favorable in early infections.
Assuntos
Prótese Vascular/efeitos adversos , Infecções Relacionadas à Prótese/cirurgia , Retalhos Cirúrgicos , Adulto , Idoso , Comorbidade , Feminino , Humanos , Tempo de Internação , Masculino , Pessoa de Meia-Idade , Prognóstico , Infecções Relacionadas à Prótese/epidemiologia , Infecções Relacionadas à Prótese/microbiologia , Estudos Retrospectivos , CicatrizaçãoRESUMO
BACKGROUND: The concept of natural breast asymmetry is well known; however, actual documentation in the literature is limited. New technology is currently available which provides 3-dimensional surface images of the breast and the ability to qualitatively determine differences in breast size, shape, and contour. The purpose of this report is to objectively determine the extent to which this natural breast asymmetry exists. METHODS: Eighty-seven women without a history of breast cancer or previous breast surgery were included. Images were obtained using 3dMD technology. Data points queried included age, parity, body mass index (BMI), ethnicity, and bra size. Left/right images were superimposed and the distance between the 2 surfaces, and contour was calculated. The degree of asymmetry was determined and comparisons were made. Similar differences in nipple-to-notch measurements were calculated and compared. Subjective evaluations were included for clinical relevance. RESULTS: The average age was 49.6 years (range: 19-77), with an average BMI of 25 (range: 18.5-36.7). The average nipple to notch on the left was 24.3 cm and 23.8 cm on the right. The nipple-to-notch asymmetry was on average 3.2%, with the left breast measurement being greater the majority of the time (62%). The mean distance between each breast demonstrated consistent breast asymmetry, with an average measurement of +0.5 mm (left breast being larger than the right). The degree of breast asymmetry was documented by a root mean square value (RMS) of 5.93 mm. This was not related to age, parity, or ethnicity; however, it was significantly higher in those patients with larger BMI, cup size, and chest-wall circumference. Only 10% of women were found to have severe breast asymmetry on subjective evaluation, which correlated objectively with the RMS in that group being significantly higher at 9.8 mm (P < 0.05). There were no predictable patterns of asymmetry; however, the most common pattern was larger laterally and smaller medially, found in 32% of the women. CONCLUSION: Natural breast asymmetry does exist, demonstrated objectively using 3-dimensional surfaces images. The left breast is on average larger than the right, with differences in size and shape being consistent but fairly unpredictable. It is important that we know baseline differences in breast symmetry prior to objectively analyzing results following esthetic and reconstructive breast surgery.