Corona virus disease 2019 (COVID-19) is an acute respiratory infectious disease with strong contagiousness, strong variability, and long incubation period. The probability of misdiagnosis and missed diagnosis can be significantly decreased with the use of automatic segmentation of COVID-19 lesions based on computed tomography images, which helps doctors in rapid diagnosis and precise treatment. This paper introduced the level set generalized Dice loss function (LGDL) in conjunction with the level set segmentation method based on COVID-19 lesion segmentation network and proposed a dual-path COVID-19 lesion segmentation network (Dual-SAUNet++) to address the pain points such as the complex symptoms of COVID-19 and the blurred boundaries that are challenging to segment. LGDL is an adaptive weight joint loss obtained by combining the generalized Dice loss of the mask path and the mean square error of the level set path. On the test set, the model achieved Dice similarity coefficient of (87.81 ± 10.86)%, intersection over union of (79.20 ± 14.58)%, sensitivity of (94.18 ± 13.56)%, specificity of (99.83 ± 0.43)% and Hausdorff distance of 18.29 ± 31.48 mm. Studies indicated that Dual-SAUNet++ has a great anti-noise capability and it can segment multi-scale lesions while simultaneously focusing on their area and border information. The method proposed in this paper assists doctors in judging the severity of COVID-19 infection by accurately segmenting the lesion, and provides a reliable basis for subsequent clinical treatment.
Humans ; COVID-19/diagnostic imaging* ; Respiratory Rate ; Tomography, X-Ray Computed

Objective:To analyze survival in patients with advanced oral cancer from prospective clinical trials. Methods:From 2008 to 2010, 256 patients with oral cancer at clinical stage III/IVA were randomly categorized into two groups. Patients in the experi-mental group received neo-adjuvant chemotherapy, surgery, and post-operative radiation, and patients in the control group underwent surgery and post-operative radiation. All patients were routinely followed-up after treatments. Survival was analyzed using Kaplan–Meier method and log-rank test, and differences were considered statistically significant at P value lower than 0.05. Results: Each group was composed of 128 patients. With the median follow-up period of 60 months, the 5-year overall survival rate was 61.7%and the disease-free survival rate was 53.9%. The overall survival rate (P=0.350) and the disease-free survival rate (P=0.160) were not sig-nificantly different between the experimental and control groups. Patients with positive pathological response to neo-adjuvant chemo-therapy exhibited significantly improved overall survival (P＜0.05). Conclusion:Radical surgery should be emphasized to improve the prognosis of oral cancer. Functional reconstruction could also improve the quality of life and survival of patients. Despite that neo-adju-vant chemotherapy could not improve the survival of patients with advanced oral cancer in entirety, it could benefit patients exhibiting positive treatment responses.

Objective:To analyze the clinical manifestations, radiographic features, and pathological classification of the juvenile ossifying fibroma (JOF) of the jaws and discuss its clinical management and prognosis. Methods: From January 2005 to December 2014, 15 patients with JOF who underwent surgery were retrospectively investigated with regard to clinical and radiologic data. On the basis of the standards of the World Health Organization in 2005, JOF was divided into juvenile psammomatoid ossifying fibroma (JPOF) and juvenile trabecular ossifying fibroma (JTOF). Results:Among the 15 patients, 10 were female and 5 were male. Patient age ranged from 7 years old to 18 years old with a mean of 10.93 years old. Nine cases were located in the mandible and 6 in the maxilla. The clinical manifestation was painless swelling of the jaw, but 20%of the cases showed jaw swelling with pain. Various JOF radiolog-ic appearances, such as radiolucent, mixed radiopaque-radiolucent, or ground-glass pattern, were observed. Ten of the 15 patients were JTOF and 5 were JPOF With regard to treatment, 4 patients underwent conservative surgery, 3 patients lived with tumors, and 11 pa-tients underwent radical surgery during the follow-up period; no lesion recurrence occurred. Nine patients underwent reconstruction, that is, 5 cases with fibula flap graft, 3 cases with free iliac graft, and 1 case with costal cartilage graft. Conclusion:JOF is a rare form of benign fibro-osseous lesions and occurs in adolescents. Mandible and maxilla are two of the most common locations. Early diagnosis and treatment and strict clinical and radiological follow-up is important in the clinic because of the aggressiveness and high recurrence rate of JOF. Operation time and treatment options should be selected according to the patients' specific situation.

Objective:To assess the effectiveness of free vascularized bone flap transfer for treatment of advanced osteoradionecrosis of the mandible (ORNM). Methods:We reviewed 53 patients who were treated for ORNM by radical resection and reconstruction with free vascularized bone flaps in our institute between January 2003 and January 2015. Results:Among the 53 vascularized bone flap patients, 48 (90.57%) had fibula osteocutaneous and 5 (9.43%) had deep circumflex iliac artery (DCIA). Postoperative complications occurred in 5 (10.42%) of the 48 fibula osteocutaneous patients (4 cases of vein thrombosis and 1 case of arterial crisis). In three of these patients, flap was salvaged back to normal in a timely manner by vascular exploratory surgery. However, pectoralis major myocutaneous flap was conducted as a second procedure for the other two patients. Meanwhile, complications occurred in 2 (40%) of the 5 DCIA transfer patients (1 case of vein thrombosis and 1 case of arterial crisis). None of these two flaps was salvaged back. Necrosis transfer bone was finally removed. No obvious donor site complications were noted. The mean follow-up time was 28 months. Our results showed that 88.57%of the patients with ORNM were stable, 85.71%of the patients can open their mouth at 2-3 figures, 85.72%of the patients can eat soft or semi-liquid food, and 80%patients can speak clearly and can be understood by others around them. No significant difference was found in mouth opening and face type of the patients with or without the intact condyle. However, the temporomandibular joint area discomfort of the patients with intact condyle was obviously less than that of patients with removed condyle. Conclusion:Radical resection, followed by vascularized bone flaps, especially fibula osteocutaneous, is still the best way to treat ORNM, as long as the indications are chosen appropriately, intraoperative work is conducted properly, and postoperative complications are controlled.

Objective:To review our patients who underwent cranio-maxillofacial resection in the recent 10 years and explore the indication of the operation. Methods:From 2003 to 2013, 116 patients underwent cranio-maxillofacial resection in our department for the treatment of tumors involving the skull base. Tumors that involved the skull base were divided into 3 types according to skull base invasions shown in the coronal planes of CT and MRI scans. Type 1 tumor was adjacent to the skull base with free bone (n=45), type 2 tumor involved the skull base with intact dura (n=30), and type 3 tumor involved dura with free brain (n=41). All patients underwent cranio-maxillofacial resection by oral and maxillofacial surgeons and neurosurgeons. The defects after cranio-maxillofacial resection were reconstructed immediately with adjacent local or regional flaps (n=62) and free vascularized flap (n=54) according to different de-fects, respectively. Results:Cranio-maxillofacial resection was successfully performed in all patients. No intraoperative complication was found. The overall success rate of soft tissue flaps and free flaps was 98.3%and 96.4%, respectively. Three patients with intracrani-al infection (n=2) and bleeding in the internal carotid artery were dead postoperatively even though they underwent salvage surgery. The overall rate of complications was 14.7%, and the dead rate was 2.6%. Recurrence or distant metastasis was found in 36 patients dur-ing the follow-up period. Conclusion: For the indication of cranio-maxillofacial resection, the balance between tumor resection and postoperative function, survival rate, and quality of life should always be considered. This technique includes the balance between func-tion and form, survival and quality of life, donor and recipient sites, and primary and secondary functions.

Objective To review our patients who underwent reconstruction of the defect after combined cranio-maxillo-facial resection in recent years.Methods From January,2005 to January,2011,88 patients underwent reconstruction of the defect after combined cranio-maxillo-facial resection.Different reconstructive techniques were used according to the defect classifications in dura,skull base bone,and facial tissues.For dural defects,no repair (37 cases),primary closure (25 cases),and dural repair (26 cases) were performed,respectively.Dural repair materials included thigh fascia lata (2 cases),temporalis fascia (2 cases),pericranium (1 case) and artificial dural patch (21 cases).Bone reconstruction of the skull base were performed in 61 patients with titanium mesh (57 cases),free iliac bone graft (1 case),free cranial bone graft (2 cases) and Medpor (1 case),respectively.Limited facial soft and hard tissue defects in 44 patients were reconstructed with temporalis system of flaps (36 cases),sternocleidomastoid myocutaneous flap (6 cases),and pterygoid muscle flap (2 cases),respectively.Extensive facial soft and hard tissue defects in 44 patients were reconstructed with free latissimus dorsi myocutaneous flap (26 cases),free pectoralis major myocutaneous flap (12 cases),free anterolateral thigh perforator flap (5 cases cases) and free anteromedial thigh perforator flap (1 case),respectively.Results The overall success rate of 88 flaps was 100％.Cerebrospinal fluid leak was found in 4 patients,wound infection was found in 2 patients,intracranial infection was found in 2 patients,respectively.Six patients with cerebrospinal fluid leak or wound infection were cured by conservative treatment.Two patients with intracranial infection were dead although they underwent salvage surgery.Overall rate of complications was 9.1％,dead rate was 2.3％.Conclusion Successful reconstruction of the defect after combined cranio-maxillo-facial resection can be achieved by watertight dural repair,bone reconstruction of the skull base and well-vascularized tissue covered.Regional flap and free tissue transfer are both preferred reconstructive technique depending on the anatomic site and the extent of the defect.

OBJECTIVEThis retrospective study is to analyze the outcomes of cN0 stage tongue squamous cell carcinoma and to discuss a reasonable neck management for these cases.

METHODSTotally 132 cases of cN0 stage tongue squamous cell carcinomas were included. Seventy-one cases were performed neck dissection(group ND), 61 cases were under wait-and-see (group WS). The clinical, pathological and follow up data of two groups were analyzed.

RESULTSThe cumulative three-year-survival between group ND and group WS were 87.3% and 83.4% respectively. In group ND, the survival of T1 and T2 cases were 89.3% and 83.3% respectively, while 89.6% and 58.3% in WS. For T2b cases which the size was larger than 3.0 cm, the survival of group WS was greatly lower than that of group ND. Both in ND and WS groups. The pathologically poor differentiation cases got poor survival than middle and well cases.

CONCLUSIONThe wait-and-see policy is recommanded for T1 stage cN0 tongue squamous cell carcinoma. For T2 cases that the tumor size is smaller than 3.0 cm, the wait-and-see is also reasonable, while the neck dissection should be considered in cases of poor differentiation. For large T2 cases, the selective neck dissection should be performed.

Adult ; Aged ; Carcinoma, Squamous Cell ; Female ; Humans ; Lymphatic Metastasis ; Male ; Middle Aged ; Neck ; Neck Dissection ; Retrospective Studies ; Survival Rate ; Tongue Neoplasms

BACKGROUND: There have been no effective means for clinical treatment of large regions of bone defects.Nano-hydroxyapatite/collagen(nHAC)composite would provide a new pathway for repair of bone defects owing to its similar structure to natural skeleton and better biocompatibility.OBJECTIVE: To investigate the role of nHAC composite co-cultured with bone marrow-derived mesenchymal stem cells(BMSCs)in repair of bone defects.METHODS: Following isolation and culture,human BMSCs were co-cultured with nHAC composite.Gross observation,histological analysis,and electron microscope observation were performed to analyze osteogenesis for repair of bone defects in the clinic.RESULTS AND CONCLUSION: Human nHAC could greatly proliferate in vitro.X-ray photography revealed that bone defects well healed after implantation of nHAC/BMSCs composite.These findings indicate that BMSCs exhibit osteogenic potential and nHAC is a satisfactory scaffold material for construction of tissue-engineered bone.

BACKGROUND:Several studies have demonstrated that stem cells can differentiate into vascular endothelial cells, and then further differentiate and form blood capillary. Based on this principle, autologous bone marrow mesenchyrnal stem cell (BMSC) transplantation promotes angiogenesis to treat ischemia in lower limb.OBJECTIVE: To evaluate the angiogenesis in rabbit ischemic limbs following autologous BMSC transplantation using high-frequency two-dimensional ultrasound detection in conjunction with Doppler color-flow imaging examination. DESIGN, TIME AND SEI-FING: A randomized, controlled, animal experiment was performed in the Third People's Hospital of Wuxi between March 2007 and April 2008.MATERIALS: Twenty-four New Zealand rabbits were randomized to a control group and a cell transplantation group, with 12 rabbits in each.METHODS: Ischemia in lower limbs was induced in all rabbits. One week following ischemia induction, the cell transplantation group was injected with 0.5 mL cell suspension, comprising 2×106 BrdU-labeled autologous BMSCs cultured in vitro, through multiple sites in the region of gastrocnemius muscle. Simultaneously, the control group received the same amount of physical saline in the same region.MAIN OUTCOME MEASURES: The initial segment of rabbit femoral artery and superficial femoral artery was subjected to high-frequency two-dimensional ultrasound and Doppler color-flow imaging examinations to measure femoral artery vascular internal diameter, blood flow peak velocity, and blood flow acceleration time. Ischemic muscular tissue was taken for immunohistochemical staining to detect transplanted cell distribution and for pathological examination of angiogenesis. RESULTS: Two weeks following autologous BMSC transplantation, high-frequency ultrasound results revealed that femoral artery internal diameter and blood flow peak velocity were greater, but blood flow acceleration time was shorter, in the cell transplantation group than in the control group (P<0.01). Immunohistochemical staining results demonstrated the presence of BrdU-positive cells. Pathological sections displayed that vascular density was significantly higher in the cell transplantation group than ih the control group. CONCLUSION: Autologous BMSC transplantation is a promising, simple, and effective method of treating ischemia in lower limbs owing to its promotion of angiogenesis. Meanwhile, high-frequency ultrasound detection of femoral artery is an effective, practical method to evaluate the clinical outcomes of autologous BMSC transplantation.

BACKGROUND: Longterm therapeutic effects of routine drug treatment, intervention or vascular bypass transplantation on lower extremity arterial occlusion are not ideal. During recent years, angiogenesis of stem cells possibly becones a new method to repair or rebuild an effective collateral circulation at infarct regions.OBJECTIVE: To verify the effect of autologous bone marrow mesenchymal stem cell transplantation on promoting angiogenesis in rabbit ischemic hind limbs.DESIGN, TIME AND SETTING: A randomized controlled animal study was performed in Jiangsu Institute of Schistosomiasis Control between August 2005 and November 2006. MATERIALS: Eight rabbits were used to prepare ischemic models of hind limbs, and then they were randomly divided into experimental group (n=4) and control group (n=4).METHODS: Bone marrow mesenchymal stem cells were isolated and cultured from New Zealand rabbits in the experimental group, and they were then marked 5-bromo-2-deoxyuridine (Brdu). Suspension of bone marrow mesenchymal stem cells was injected into the ischemic hind limbs in the experimental group, while the same volume of saline was injected into the controls. MAIN OUTCOME MEASURES: After two weeks, two-dimensional and color Doppler ultrasound detection was used on rabbit femoral artery to measure inner diameter of blood vessel, peak velocity and acceleration time of blood flow before and after transplantation. Muscle tissues were obtained from ischemic regions to observe distribution of transplant cells and state of angiogenesis using immunofluorescence staining and hematoxylin-eosin (HE) staining. RESULTS: Two weeks after transplantation, the inner diameter of femoral artery and the peak velocity of blood flow in the experimental group were higher than those in the control group (P < 0.01), but the acceleration time of blood flow was shorter than that in the control group (P < 0.01). Lmmunofluorescence staining showed that anti-Brdu-staining positive cells were found out in transplant part in the experimental group; while HE staining indicated that vessel density of ischemic region in the experimental group was higher than that in the control group. CONCLUSION: Bone marrow mesenchymal stem cells can promote angiogenesis, while autologous bone marrow mesenchymai stem cell transplantation will become a simple and effective method to treat lower limb ischemia.