Total Surface Area of a Through-and-Through Oromandibular Defect Is Associated With Thromboembolic Events for Reconstruction With a Single Fibula Free Flap.

BACKGROUND: Reconstruction of through-and-through composite oromandibular defects (COMDs) has been a challenge to plastic surgeons for decades. When using a free osteoseptocutaneous fibular flap, the skin paddle is restricted by the orientation of the peroneal vessels and the inset of bone segment(s). Although the combination of double flaps for extensive COMDs is viable and reliable, the decision of single- or double-flap reconstruction is still debated, and the risk factors leading to complications and flap failure of single-flap reconstruction are less discussed. AIM AND OBJECTIVES: The aim of this study was to determine objectively predictive factors for postoperative vascular complications in through-and-through COMDs reconstructed with a single fibula flap. METHODS: This was a retrospective cohort study in patients who underwent single free fibular flap reconstruction for through-and-through COMDs in a tertiary medical center from 2011 to 2020. The enrolled patients' characteristics, surgical methods, thromboembolic event, flap outcomes, intensive care unit care, and total hospital length of stay were analyzed. RESULTS: A total of 43 consecutive patients were included in this study. Patients were categorized into a group without thromboembolic events (n = 35) and a group with thromboembolic events (n = 8). The 8 subjects with thromboembolic events were failed to be salvaged. There was no significant difference in age, body mass index, smoking, hypertension, diabetes mellitus, and history of radiotherapy. The length of bony defect (6.70 ± 1.95 vs 9.04 ± 2.96, P = 0.004) and the total surface area (105.99 ± 60.33 vs 169.38 ± 41.21, P = 0.004) were the 2 factors that showed a significant difference between the groups. Total surface area was the only significant factor in univariate logistic regression for thromboembolic event (P = 0.020; odds ratio, 1.02; 95% confidence interval [CI], 1.003-1.033) and also in multivariate logistic regression analysis after adjusting confounding factors (P = 0.033; odds ratio, 1.026; 95% CI, 1.002-1.051).The cutoff level of total surface area in determining thromboembolic event development was 159 cm2 (P = 0.005; sensitivity of 75% and specificity of 82.9%; 95% CI, 0.684-0.952). CONCLUSIONS: Free fibula flap has its advantages and drawbacks on mandible restoration. Because there is a lack of indicators before, a large total surface area may be an objective reference for single-flap reconstruction of through-and-through COMDs due to an elevated risk of thromboembolic event.

Arcade Suture Upper Blepharoplasty Combined With the Forceps Technique.

BACKGROUND: Double-eyelid blepharoplasty is the most popular cosmetic surgery in Taiwan. The creation of a small palpebral fold along with reduction of eyelid fullness makes the eye look slightly larger, thereby leading to an appearance of youthfulness, alertness, and vitality. Herein, we propose a method of combining the techniques of arcade buried suture and forceps, which is designed to create a more physiologically natural double eyelid. MATERIALS AND METHODS: We conducted a retrospective review of 45 patients who underwent double-eyelid surgery between December 2015 and December 2019. The procedures were performed by one senior surgeon using arcade suture upper blepharoplasty combined with the forceps technique. The patients' age ranged from 18 to 38 years (mean, 28 years). Ninety-one percent of the patients were women and were undergoing surgery for cosmetic reasons. RESULTS: Of the 45 patients who underwent arcade suture upper blepharoplasty with the forceps technique, no patients developed stitch abscess or granuloma, obvious asymmetry, disappearance of line, chemosis, and corneal injury. The follow-up period ranged from 3 months to 4 years (mean, 32 months). Patient satisfaction was very high. CONCLUSIONS: The arcade suture upper blepharoplasty combined with the forceps technique is a simple method for establishing a durable double eyelid without serious complication and providing excellent results.

Perioperative Myocardial Infarction in Free Flap for Head and Neck Reconstruction.

INTRODUCTION: Acute myocardial infarction (AMI) is a postoperative complication of major surgical procedures, including free flap surgery. It is the most common cause of postoperative morbidity and mortality. Moreover, patients receiving free flap reconstruction for the head and neck have significant risk factors such as coexisting coronary artery disease (CAD). Our primary aim was to ascertain predictors of perioperative AMI to enable early detection and consequently early treatment of perioperative AMI. Our secondary aim was to determine the group of patients who would be at a high risk for perioperative AMI after free flap surgery. MATERIALS AND METHODS: This retrospective study enrolled patients who underwent free flap reconstruction surgery at the Division of Plastic and Reconstructive Surgery of Taipei Veterans General Hospital between 2013-01 and 2017-12. RESULTS: This study included 444 patients and 481 free flap head and neck reconstruction surgeries. Fifteen (3.1%) patients were diagnosed with perioperative AMI. Statistical analysis of the variables revealed that patients with underlying CAD or cerebrovascular accident (CVA) were at a high risk of developing perioperative AMI (odds ratio: 6.89 and 11.11, respectively). The flap failure rate was also higher in patients with perioperative AMI compared with those without perioperative AMI (P = 0.015). CONCLUSIONS: Patients with underlying diseases, such as CAD or CVA, constituted high-risk groups for perioperative AMI.

Frozen Fat Grafts Maintain Vascular Endothelial Growth Factor Expression and Mediate Angiogenesis During Adipose-Derived Stem Cell Enrichment for Soft Tissue Augmentation.

BACKGROUND: Fresh fat grafts are commonly used in both esthetic and reconstructive surgeries, but the graft resorption rate varies. Cryopreservation of unused fat for later touch-up is one option to resolve this variation. In our previous studies, we found that fat cryopreservation may be a practical strategy for storing fat tissue. To explore the cryopreservation method, we evaluated the role of vascular endothelial growth factor (VEGF) in human frozen fat grafts. METHODS: The concentration of VEGF in human frozen fat grafts subjected to different preservation times was determined using Western blotting and enzyme-linked immunosorbent assay. The angiogenic effect of frozen fat grafts was evaluated using a chorioallantoic membrane assay. Furthermore, the impact of adding human adipose-derived stem cells (hADSCs) or different concentrations of avastin (bevacizumab) to frozen fat grafts on angiogenesis was assessed. The viability of frozen fat grafts with or without hADSCs was evaluated using a nude mouse implantation study. Explanted fat tissues were examined on days 1, 4, 7, 14, 28, and 90, and morphological and histological analyses, immunohistochemistry, and enzyme-linked immunosorbent assay (VEGF concentration) were carried out. RESULTS: No significant difference in VEGF concentration between fresh and frozen fat was observed with respect to preservation duration. In the chorioallantoic membrane assay, frozen fat grafts with hADSCs displayed significantly enhanced angiogenesis. Avastin was found to decrease angiogenesis in frozen fat grafts. However, in the nude mouse implantation study, frozen fat grafts displayed VEGF maintenance, with the highest concentration observed on day 7. Adding hADSCs to the graft further increased the VEGF concentration and CD31 expression. Fat graft viability was found to be higher in the frozen fat grafts containing hADSCs than in grafts without hADSCs. CONCLUSIONS: Human fat grafts can maintain VEGF expression under frozen conditions for at least 12 months. The addition of hADSCs to the frozen fat graft could further enhance angiogenesis, VEGF expression, and fat cell viability.

Accuracy of the Application of 3-Dimensional Printing Models in Orbital Blowout Fractures-A Preliminary Study.

BACKGROUND: Application of 3-dimensional (3D) printing technology has grown in the medical field over the past 2 decades. In managing orbital blowout fractures, 3D printed models can be used as intraoperative navigators and could shorten the operational time by facilitating prebending or shaping of the mesh preoperatively. However, a comparison of the accuracy of computed tomography (CT) images and printed 3D models is lacking. MATERIAL AND METHODS: This is a single-center retrospective study. Patients with unilateral orbital blowout fracture and signed up for customized 3D printing model were included. Reference points for the 2D distance were defined (intersupraorbital notch distance, transverse horizontal, sagittal vertical, and anteroposterior axes for orbital cavity) and measured directly on 3D printing models and on corresponding CT images. The difference and correlation analysis were conducted. RESULTS: In total, 9 patients were reviewed from June 2017 to December 2020. The mean difference in the intersupraorbital notch measurement between the 2 modules was -0.14 mm (P = 0.67). The mean difference in the distance measured from the modules in the horizontal, vertical, and anteroposterior axes of the traumatic orbits was 0.06 mm (P = 0.85), -0.23 mm (P = 0.47), and 0.51 mm (P = 0.32), whereas that of the unaffected orbits was 0.16 mm (P = 0.44), 0.34 mm (P = 0.24), and 0.1 mm (P = 0.88), respectively. Although 2D parameter differences (<1 mm) between 3D printing models and CT images were discovered, they were not statistically significant. CONCLUSIONS: Three-dimensional printing models showed high identity and correlation to CT image. Therefore, personalized models might be a reliable tool of virtual surgery or as a guide in realistic surgical scenarios for orbital blowout fractures.

Long-Term Complications and Patient-Reported Outcomes After Alloplastic Breast Reconstruction.

BACKGROUND: The most widely used method for breast reconstruction in Taiwan is alloplastic breast reconstruction, and traditionally, it can be categorized into immediate or delayed, single-stage or 2-stage procedures. We evaluated clinical outcomes and analyzed patients' self-reported satisfaction and quality of life after alloplastic breast reconstruction based on a previous preliminary study. PATIENT AND METHODS: The patients who underwent primary alloplastic breast reconstruction after mastectomy were recruited in 2006 to 2020 at a single institute in Taiwan. The assessment of clinical outcomes was conducted by retrospective chart review and risk analysis. The patients also completed the BREAST-Q, a condition-specific patient-reported outcome measure, at least 6 months after treatment. RESULTS: A total of 237 patients with 247 reconstructed breasts were enrolled in this study. The demographics showed that 205 (83%) were reconstructed using a 2-stage tissue expander-based procedure and 42 (17%) were 1-stage direct-to-implant reconstructions. The mean follow-up time was 79.5 months. The clinical assessment revealed that the overall complication rate was 34%, with infection being the most common (21 patients; 8%). According to risk analysis, smoking (odds ratio, 7.626; 95% confidence interval, 1.56-37.30; P = 0.012), and nipple-sparing mastectomy (odds ratio, 3.281; 95% confidence interval, 1.54-6.99; P = 0.002) were significant risk factors for overall complications. The questionnaire response rate was 38% (94 of 247), at least 6 months after treatment. The total mean score was 69.78. CONCLUSIONS: At a single institute in Taiwan from 2006 to 2020, alloplastic breast reconstruction, either single- or 2-stage, have acceptable complication rate and good postoperative satisfaction based on patient-reported outcomes. Both patient- and surgery-related factors presented as significant risk factors. Precise patient selection and comprehensive discussion between the patient and physician may play the important role to achieve optimal aesthetic outcomes.

The Effect of Biological Scaffold (Biodesign) in Postmastectomy Direct-to-Implant Breast Reconstruction: A 5-Year Single-Institution Experience.

BACKGROUND: Direct-to-implant (DTI) breast reconstruction is one of the immediate implant-based breast reconstruction methods. If the amount of soft tissue (eg, muscle or fascia) is insufficient to completely cover the implant, biological scaffold or acellular dermal matrix can be safely used for implant coverage. In this study, we used an acellular porcine small intestinal submucosa (SIS) mesh (Biodesign; Cook Medical Inc, Bloomington, IN) for DTI reconstruction to explore the impact of its use on breast reconstruction results. METHODS: We retrospectively assessed cases involving DTI reconstruction at Taipei Veterans General Hospital from 2015 to 2019. Women, 18 years or older, who underwent immediate DTI reconstruction after mastectomy were included in the study. Mastectomy may have been performed because of therapeutic or prophylactic reasons. Patients who did and did not use SIS mesh for reconstruction were studied separately, and the 2 groups were compared in terms of clinical outcomes and complications. The validated, self-administered BREAST-Q Reconstruction Module version 2.0 survey was used to evaluate health-related quality of life and satisfaction among patients who underwent breast reconstruction. RESULTS: A total of 30 DTI breast reconstructions were enrolled. The mean age was 49.2 years, and the mean body mass index was 22.3 kg/m2. The mean postoperative follow-up duration was 17.1 months. Nipple-sparing mastectomy was performed for 26 cases (86.7%), and DTI breast reconstructions using SIS mesh for implant coverage were done in 14 cases (46.7%). The overall complication rate was 53.3% in 30 reconstructions, with nipple complications being the most common complication. The non-SIS and SIS-using groups had a similar overall complication rate postoperatively. As for the quality-of-life assessment, the SIS group obtained a higher score on BREAST-Q than those for whom SIS was not used. CONCLUSIONS: Porcine SIS mesh might be a safe and effective alternative to biological scaffolds in immediate 1-stage implant-based breast reconstruction to improve the quality of life after surgery.

Postoperative Sedation Duration as an Independent Risk Factor for Postoperative Pneumonia in Head and Neck Cancer Patients Undergoing Free Flap Reconstruction.

OBJECTIVE: Patients who had reconstruction for head and neck cancer usually have long duration of postoperative sedation and intensive care. This is due to the complex nature of large-area soft tissue defect surgeries and upper respiratory tract infections associated with them. Postoperative pulmonary complications are common in these patients. In this study, we analyzed the risk factors and the relationship between postoperative complications and the duration of sedation to improve the patients' recovery process after free flap reconstruction for head and neck surgery. MATERIALS AND METHODS: This was a retrospective study that included 188 patients who had head and neck surgery with free flap reconstruction in 2011 (traditional recovery group) and 2018 (early recovery group). Postoperative recovery events were compared between the 2 groups. Complications such as pneumonia, wound infection, vascular thrombosis, and bleeding were also analyzed. RESULTS: The results showed that the early recovery group had a shorter duration of sedation (P < 0.001), shorter duration of intensive care unit stay (P = 0.05), more rapid ventilator weaning (P < 0.001), and fewer pneumonia events (8.8% vs 39.1%) than the traditional recovery group. Wound- and vessel-related complications were not affected by the duration of sedation. CONCLUSIONS: Our study demonstrated that shortening the duration of postoperative sedation can effectively decrease the length of intensive care unit stay and reduce postoperative incidence of pneumonia without increasing wound- and vessel-related complications.

Survival analysis of extramammary Paget's disease (EMPD) in a tertiary hospital in Taiwan.

BACKGROUND: This study aimed to investigate the survival analysis of extramammary Paget's disease (EMPD) in a Taiwanese population and to provide data for comparison with other studies in various locations and racial populations. METHODS: We retrospectively analyzed the medical records of 63 patients with EMPD who were surgically treated from 2002 to 2019 at a single institution. The primary endpoint was the 5-year overall survival rate of EMPD, and the secondary endpoint was recurrence-free 5-year survival. Independent variables included patients' demographic data, concurrent malignancy (i.e., non-EMPD-related cancers), tumor size, distant metastasis, and surgery and/or radiation. RESULTS: Of all the 63 patients, 8 cases were excluded. A total of 43 patients (78.18%) were male, and 12 were female, with a mean age of 72.67 years (range 44-89 years). The most common affected anatomic site was the penoscrotal region (22 patients, 40.00%), followed by the perianal and perineal regions (17 patients, 30.91%). Among the 55 patients, 41 patients (74.55%) were diagnosed with at least one underlying disease, whereas the most common underlying disease was cardiovascular disease (30 patients, 54.55%). The overall survival rate was 80.00% at 36 months and 65.45% at the end of follow-up. EMPD with deep dermal invasion was a significant poor prognostic factor of overall survival in cause-specific hazard model (sub-hazard ratio (HR) 5.167, p = 0.0015, 95% confidence interval (CI) 1.876-14.230). Patients with regional metastasis or distant metastasis had poorer prognosis of 5-year survival (sub-HR 4.513, p = 0.0028, CI 1.683-12.103). The limitations of this study include its retrospective nature and sample size. CONCLUSIONS: In our series, EMPD with metastasis and deep dermal invasion was the significant harmful factors in both overall 5-year survival and 5-year recurrence-free survival. The surgical excision is not associated with a low risk of local recurrence or overall survival, and long-term follow-up is still needed.

Using Various Skin Graft Techniques in Major Burn Reconstruction: A Lesson Learned From a Taiwanese Cornstarch Explosion.

PURPOSE: Four hundred and ninety-nine patients had burn injuries in an explosion in Taiwan on June 27, 2015, 24 were admitted to the intensive care units of Taipei Veterans General Hospital. This study details our experience with surgical management of these patients, focusing primarily on various skin graft techniques. MATERIALS AND METHODS: This single-center retrospective study included patients who underwent at least one of the previously mentioned skin graft techniques because of extensive skin defects. The demography, burn diagram, treatment modalities, postoperative outcome, and costs were all analyzed, and a comparison with traditional mesh skin grafts was performed. The literature was also reviewed. RESULTS: Fourteen patients underwent the Meek skin graft technique. Only 3 received ReCell and 1 cultured epithelial autograft (CEA) at separate time point. Overall, the autologous skin grafts, including Meek/ReCell/CEA were completed within 6 months. The average skin graft success rate was approximately 72.9%, 79.2%, and 38% in Meek, ReCell, and CEA, respectively. The infection rate was approximately 35.7%, 25%, and 100% in Meek, ReCell, and CEA, respectively. The average surgical cost and total medical cost were significantly higher in patients who underwent Meek/ReCell/CEA treatments. CONCLUSIONS: In our experience, Meek and ReCell treatments had acceptable success rates, but CEA treatment not. ReCell and CEA treatments are useful in the event of extremely limited donor sites, and they are fragile, easily infected, and technically challenging. These techniques also require longer hospitalization and tend to be more expensive, all factors that should be considered when assessing treatment options.

MMP-9 Deletion Attenuates Arteriovenous Fistula Neointima through Reduced Perioperative Vascular Inflammation.

Matrix metalloproteinase 9 (MMP-9) expression is upregulated in vascular inflammation and participates in vascular remodeling, including aneurysm dilatation and arterial neointima development. Neointima at the arteriovenous (AV) fistula anastomosis site primarily causes AV fistula stenosis and failure; however, the effects of MMP-9 on perioperative AV fistula remodeling remain unknown. Therefore, we created AV fistulas (end-to-side anastomosis) in wild-type (WT) and MMP-9 knockout mice with chronic kidney disease to further clarify this. Neointima progressively developed in the AV fistula venous segment of WT mice during the four-week postoperative course, and MMP-9 knockout increased the lumen area and attenuated neointima size by reducing smooth muscle cell and collagen components. Early perioperative AV fistula mRNA sequencing data revealed that inflammation-related gene sets were negatively enriched in AV fistula of MMP-9 knockout mice compared to that in WT mice. qPCR results also showed that inflammatory genes, including tumor necrosis factor-α (TNF-α), monocyte chemoattractant protein-1 (MCP-1), interleukin-6 (IL-6), intercellular adhesion molecule-1 (ICAM-1), and vascular cell adhesion molecule-1 (VCAM-1), were downregulated. In addition, Western blot results showed that MMP-9 knockout reduced CD44 and RAC-alpha serine/threonine-protein kinase (Akt) and extracellular signal-regulated kinases (ERK) phosphorylation. In vitro, MMP-9 addition enhanced IL-6 and MCP-1 expression in vascular smooth muscle cells, as well as cell migration, which was reversed by an MMP-9 inhibitor. In conclusion, MMP-9 knockout attenuated AV fistula stenosis by reducing perioperative vascular inflammation.

Review of preclinical and clinical studies of using cell-based therapy for secondary lymphedema.

Secondary lymphedema is associated with impaired lymph fluid drainage and remains incurable. Alternatively, cell-based therapy may pave the way for lymphedema treatment. We found 11 animal and seven human studies had been conducted from 2008 to 2018. Most studies showed great potential for this treatment modality. Emerging studies have focused on novel techniques, such as coupling cell therapy with lymph node transfer, or adding growth factors to cell therapy.

Salivary Gland Tumors: A Clinicopathologic Analysis From Taipei Veterans General Hospital.

BACKGROUND: The aim of this study was to investigate the epidemiological and clinical characteristics of salivary gland tumors (SGTs) in a Taiwanese population and to provide data for comparison with other studies in various locations and racial populations. METHODS: We retrospectively analyzed the medical records of 559 patients with tumors of the salivary glands who were surgically treated from 2002 to 2017 at a single institution. RESULTS: There were 430 benign and 129 malignant tumors with a mean age of 53.5 years (range, 1-91 years). The mean age of patients with benign SGTs was 52.6 years, and the mean age of patients with malignant SGTs was 55.8 years. Most findings were similar to those reported in literature, with some variations. The salivary tumors slightly predominated in males. There were no differences in age and incidence of benign or malignant major SGTs between males and females. The frequency was 76.9% for benign tumors (430 patients) and 23.1% for malignant tumors (129 patients). The majority of the tumors occurred in the parotid gland (351 cases), followed by the submandibular gland (152 cases), the minor salivary glands (46 cases), and, lastly, the sublingual gland (10 cases). Minor SGTs occurred most frequently on the palate, with pleomorphic adenoma, the most frequent benign tumor type, and adenoid cystic carcinoma and mucoepidermoid carcinoma, the commonest malignant tumor types. Tumors of the sublingual gland were rare, but 80% were malignant. CONCLUSIONS: In our series, SGTs were uncommon neoplasms that typically arose in the parotid gland. Benign tumors were far more common than malignant tumors. Pleomorphic adenoma was the most common benign tumors. Adenoid cystic carcinoma and mucoepidermoid carcinoma constituted the most common malignancies. Almost 60% of the tumors arising from minor salivary glands were malignant; thus, special care must be taken when these glands are affected.

Primary Merkel Cell Carcinoma: The Clinical Experience of Taipei Veterans General Hospital Revisited.

BACKGROUND: Merkel cell carcinoma (MCC) is rare among Asians. To evaluate the presence and characteristics of MCC in Taiwan, we described the characteristics, treatment, and prognostic findings of MCC in our institution. METHODS: We revisited and carried out a retrospective chart review of 16 consecutive patients with MCC treated from 1995 to 2018. Patient demographic data, tumor size, location, previous treatment, and follow-up data about presence of locoregional recurrence and metastasis were evaluated. RESULTS: There were 14 male and 2 female patients (mean age = 75.1 years; range = 26-91 years). Clinical follow-up revealed local recurrences in 5 patients 1 to 4 months after surgical excision. Lymph node metastasis was observed in 3 patients. We reviewed previously published articles and analyzed the clinical findings, pathologic examinations, and treatments. CONCLUSIONS: Surgical wide excision of the primary tumor remains the mainstay of treatment for patients with local/regional MCC. Additional management strategies, such as lymphadenectomy, radiotherapy, chemotherapy, and targeted therapy, depend on the presence or absence of clinically detectable lymph node disease. The prognosis for MCC is variable. Our findings highlight the importance of maintaining a high clinical suspicion for this malignancy in the appropriate clinical context to avoid delays in diagnosis and management.

Prognostic Factors and Clinical Outcomes of Clinical Node-Negative Cutaneous Malignant Melanoma Patients: An Asian Single Institute Study.

INTRODUCTION: Cutaneous malignant melanoma is notorious for its aggressive behavior and relatively poor outcome compared with other common skin malignancies. Acral lentiginous melanoma (ALM) accounts for at least 50% of melanoma in the Asian population and has a significantly lower survival rate. However, previous studies of the prognostic factors of melanoma-specific survival were all conducted from Western institutions. Here, we performed a retrospective analysis to investigate this issue. METHODS: Fifty patients diagnosed as having clinical node-negative cutaneous malignant melanoma who underwent sentinel lymph node (SLN) biopsy at Taipei Veterans General Hospital between January 2007 and December 2018 were enrolled. Patient demographics, tumor characteristics, and lymph node characteristics were evaluated by chart review. RESULTS: Eighty-two percent of the melanoma in the sample population was ALM. Twelve patients (24.0%) presented at least 1 metastatic sentinel node, and the average number of retrieved SLNs was 3. Of the patients with positive SLNs who proceeded to completion lymph node dissection, only 2 (16.7%) had metastatic nonsentinel nodes (NSNs). The average follow-up time for all patients was 45 months. Recurrence and melanoma-specific death occurred in 21 patients (42.0%) and 15 patients (30.0%), respectively. Melanoma-specific survival was significantly lower in patients with ulcerative lesions (P = 0.005) and more metastatic SLNs (P = 0.036). The overall morbidity rate of completion lymph node dissection was 66.7%. CONCLUSIONS: The presence of ulcerations and number of metastatic SLNs were the most important prognostic factors in this ALM-dominant Asian cohort. Among patients with clinically negative nodes but positive SLNs, less than one-fourth of patients harbored metastatic NSNs. Completion lymph node dissection carries a relatively high risk of morbidity; therefore, further research regarding predictors of positive NSNs in the Asian population is necessary.

Determinants of Free Fasciocutaneous Flap Outcomes in Partial Hypopharyngeal Defects.

BACKGROUND: Most of the patients with hypopharyngeal cancer are still diagnosed with advanced stage, and total or partial pharyngectomy with free flap reconstruction is the mainstay of treatment. The aim of this study was to find out the possible risk factors related to surgical complications after free fasciocutaneous flap reconstruction for partial pharyngeal defect and its sequelae in the follow-up. PATIENTS AND METHODS: We retrospectively reviewed the charts of patients with advanced hypopharyngeal cancer who received free fasciocutaneous flaps for partial pharyngeal defects reconstruction. From 2005 to 2015, 79 free fasciocutaneous flaps (59 free fasciocutaneous flaps and 20 anterolateral thigh flaps) were performed in our department. The risk factors for free flap outcome and complications were evaluated with multivariant linear regression model. RESULTS: The mean age of patients was 60.8 years with male predominance. The mean follow-up duration was 39.6 months. Most of the cases (97.5%) were in stage III or IV. Patients with comorbidities showed significant correlation to flap failure (95% confidence interval [CI] = 0.038 to 0.264, P = 0.10). Anastomosis style (end-to-side vs end-to-end) was the only operation-related factors significantly related to flap failure rate (18.8% vs 3.2%, 95% CI = 0.031 to 0.32, P = 0.18). Flap size was significantly associated with fistula formation (95% CI = -0.005 to 0.000, P = 0.38). CONCLUSIONS: In our experience, patients with comorbidities and end-to-side anastomosis illustrate significantly higher flap failure rate in free fasciocutaneous flap reconstruction of partial hypopharyngeal defect. Reconstruction with smaller flap size had higher possibility of fistula formation.

The Antithrombotic Function of Sphingosine-1-Phosphate on Human Adipose-Stem-Cell-Recellularized Tissue Engineered Vascular Graft In Vitro.

Adipose stem cells (ASCs) show potential in the recellularization of tissue engineerined vascular grafts (TEVGs). However, whether sphingosine-1-phosphate (S1P) could further enhance the adhesion, proliferation, and antithrombosis of ASCs on decellularized vascular scaffolds is unknown. This study investigated the effect of S1P on the recellularization of TEVGs with ASCs. Human ASCs were derived from lipoaspirate. Scaffolds were derived from human umbilical arteries (HUAs) with treatment of 0.1% sodium dodecyl sulfate (SDS) for 48 h (decellularized HUAs; DHUAs). The adhesion, proliferation, and antithrombotic functions (kinetic clotting time and platelet adhesion) of ASCs on DHUAs with S1P or without S1P were evaluated. The histology and DNA examination revealed a preserved structure and the elimination of the nuclear component more than 95% in HUAs after decellularizaiton. Human ASCs (hASCs) showed CD29(+), CD73(+), CD90(+), CD105(+), CD31(-), CD34(-), CD44(-), HLA-DR(-), and CD146(-) while S1P-treated ASCs showed marker shifting to CD31(+). In contrast to human umbilical vein endothelial cells (HUVECs), S1P didn't significantly increase proliferation of ASCs on DHUAs. However, the kinetic clotting test revealed prolonged blood clotting in S1P-treated ASC-recellularized DHUAs. S1P also decreased platelet adhesion on ASC-recellularized DHUAs. In addition, S1P treatment increased the syndecan-1 expression of ASCs. TEVG reconstituted with S1P and ASC-recellularized DHUAs showed an antithrombotic effect in vitro. The preliminary results showed that ASCs could adhere to DHUAs and S1P could increase the antithrombotic effect on ASC-recellularized DHUAs. The antithrombotic effect is related to ASCs exhibiting an endothelial-cell-like function and preventing of syndecan-1 shedding. A future animal study is warranted to prove this novel method.

Sphingosine-1-phosphate in Endothelial Cell Recellularization Improves Patency and Endothelialization of Decellularized Vascular Grafts In Vivo.

BACKGROUND: S1P has been shown to improve the endothelialization of decellularized vascular grafts in vitro. Here, we evaluated the potential of tissue-engineered vascular grafts (TEVGs) constructed by ECs and S1P on decellularized vascular scaffolds in a rat model. METHODS: Rat aorta was decellularized mainly by 0.1% SDS and characterized by histology. Rat ECs, were seeded onto decellularized scaffolds, and the viability of the ECs was evaluated by biochemical assays. Then, we investigated the in vivo patency rate and endothelialization for five groups of decellularized vascular grafts (each n = 6) in a rat abdominal aorta model for 14 days. The five groups included (1) rat allogenic aorta (RAA); (2) decellularized RAA (DRAA); (3) DRAA with S1P (DRAA/S1P); (4) DRAA with EC recellularization (DRAA/EC); and (5) DRAA with S1P and EC recellularization (DRAA/EC/S1P). RESULTS: In vitro, ECs were identified by the uptake of Dil-Ac-LDL. S1P enhanced the expression of syndecan-1 on ECs and supported the proliferation of ECs on decellularized vascular grafts. In vivo, RAA and DRAA/EC/S1P both had 100% patency without thrombus formation within 14 days. Better endothelialization, more wall structure maintenance and less inflammation were noted in the DRAA/EC/S1P group. In contrast, there was thrombus formation in the DRAA, DRAA/S1P and DRAA/EC groups. CONCLUSION: S1P could inhibit thrombus formation to improve the patency rate of EC-covered decellularized vascular grafts in vivo and may play an important role in the construction of TEVGs.

Detection of free flap pedicle thrombosis by infrared surface temperature imaging.

BACKGROUND: Reliable detection of any circulatory issue threatening flap viability after free flap surgery is essential for prompt flap salvage. Currently, the gold standard of flap monitoring is clinical monitoring. However, this method presents logistical challenges to insufficient trained personnel. Auxiliary methods are becoming increasingly vital. MATERIALS AND METHODS: Twelve swine pedicle myocutaneous flaps were harvested and monitored using infrared cameras to investigate the developed monitoring parameters and vascular thrombosis in the free flap model. RESULTS: The mean flap surface temperature after vein or artery occlusion decreased significantly, but the differences were relatively small. As a result, the difference between recorded (flap surface temperature [Ts]) and predicted (estimated surface temperature [Tes]) flap surface temperature (ΔT = Ts- Tes) was used as the parameter for pedicle thrombosis. A ΔT of <0.86°C was used as a vascular occlusion criterion; the sensitivity and specificity of this parameter were 90% and 81%, respectively. The standard deviation of the surface temperature (SDT) was another indicator of vascular occlusion; the estimated sensitivity and specificity for vessel occlusion of SDT < 0.48°C were 84% and 73%, respectively. CONCLUSIONS: Infrared thermal imaging has the advantages of being noninvasive, contact-free, continuous, and able to detect the whole flap surface area. Two indicators, ΔT and SDT, can be used with high sensitivity and specificity for early prediction of flap pedicle thrombosis. Further human studies are necessary to validate clinical application of infrared thermal imaging.

Fractional CO2 laser contributes to the treatment of non-segmental vitiligo as an adjunct therapy: a systemic review and meta-analysis.

The treatment of stable non-segmental vitiligo is often challenging, which new therapies are being searched. Multiple clinical trials have proposed the benefits and safety of using fractional carbon dioxide (CO2) laser as an adjunct therapy to conventional treatments. This study aimed to evaluate the safety and efficacy of fractional carbon dioxide laser as a combination therapy to conventional treatments in patients with stable non-segmental vitiligo. A literature search using PubMed, EMBASE, and the Cochrane Library was performed for comparative studies among vitiligo patients treated with additional fractional CO2 laser. Clinical outcomes in the selected studies were compared, and a meta-analysis was performed via Review Manager version 5.3, according to the PRISMA guidelines. Six studies with a total of 184 patches/patients were included in the present meta-analysis. The combination therapy group had significantly superior results than that of the control group (≥ 75% re-pigmentation, risk ratio [RR] 2.80, 95% confidence interval [CI] 1.29-6.07; ≥ 50% re-pigmentation, RR 2.26, 95% CI 1.23-5.9; < 25% re-pigmentation, RR 0.57, 95% CI 0.43-0.75). Limitations of the study included the small number of studies and sample size, inadequate blinding of participants, and variation between therapy protocols. Meta-analysis revealed that using fractional CO2 laser in combination with conventional treatments is efficient and safe, and may be considered as an adjunct therapeutic option for patients with refractive non-segmental vitiligo.