Objective:To evaluate the effect of mixed reality (MR) in the standardized resident training on oral and maxillofacial-head and neck tumor surgery.Methods:Twenty resident doctors, who received standardized training in the department of maxillofacial oncology of our hospital, were randomly divided into experimental group and control group. The MR teaching method was used in the experimental group, while the traditional teaching method was used in the control group. The teaching effect was evaluated by theoretical and operational tests and a questionnaire survey. Statistical analysis was performed with the SPSS 24.0 software. Statistical comparisons were performed by the Students' t-test or the Wilcoxon rank correlation test. Results:The theoretical test results showed that the scores of the experimental group were significantly higher than those of the control group (85.30±3.59 vs. 80.20±5.63, t = 2.41, P = 0.027). The operational test results showed that the scores of the experimental group were significantly higher than those of the control group (89.20±5.07 vs. 82.30±6.36, t = 2.68, P = 0.015). The questionnaire survey results showed that the MR teaching helped to easily acquire the knowledge of head and neck anatomy and operation skills. Besides, the doctors in the experimental group were more active and glad to communicate with others than those in the control group. In addition, the MR teaching method improved the learning interest of doctors. The doctors in the experimental group were more satisfied with the teaching effect than those in the control group, and they recommended that the MR teaching method be used in clinical training and teaching on oral and maxillofacial-head and neck tumor surgery. Conclusion:MR teaching can help doctors understand and master the knowledge of head and neck anatomy and operation skills and improve their learning interest, achieving a good teaching effect, so it has important application value in the standardized resident training on oral and maxillofacial-head and neck tumor surgery.

Objective:To explore the clinical efficacy and adverse reactions of albumin-bound paclitaxel (Nab-P) and conventional paclitaxel combined with cisplatin and concurrent radiotherapy for the treatment of patients with locally advanced esophageal squamous cell carcinoma.Methods:Forty-nine patients with locally advanced esophageal squamous cell carcinoma admitted to the First People's Hospital of Suqian from November 2016 to May 2020 were included. Of the 49 patients, 23 cases were treated with Nab-P combined with cisplatin and concurrent radiotherapy (NP group), 26 cases were treated with conventional paclitaxel combined with cisplatin and concurrent radiotherapy (TP group). All patients received 2 cycles of chemotherapy. The curative efficacy was evaluated one month after the end of radiotherapy, and the curative effect and adverse reactions of the two treatment regimens were compared.Results:The objective remission rate in NP group was 78.3% (18/23), and the disease control rate was 100.0% (23/23). The objective response rate in TP group was 61.5% (16/26), and the disease control rate was 92.3% (24/26). The objective response rate and disease control rate in NP group were higher than those in TP group, but the differences were not statistically significant (both P > 0.05). The common adverse reactions were mainly hair loss, loss of appetite, bone marrow suppression, radiation esophagitis, radiation pneumonia, malaise and myalgia. The incidence rate of grade 3-4 acute bone marrow suppression in NP group (8.7%, 2/23) was lower than that in TP group (38.5%, 10/26), and the difference was statistically significant ( χ2 = 4.35, P = 0.037). The incidence rate of myalgia in NP group (26.1%, 6/23) was lower than that in TP group (61.5%, 16/26), and the difference was statistically significant ( χ2 = 4.85, P = 0.028). Conclusions:Nab-P combined with cisplatin and concurrent radiotherapy has good efficacy in the treatment of patients with locally advanced esophageal squamous cell carcinoma, and the incidence rate of adverse reactions is lower than that of conventional paclitaxel combined with cisplatin and concurrent radiotherapy, so that the regimen is safe.

Objective:To compare the effect of three-dimensional CT angiography (CTA) and color Doppler ultrasound (CDU) in reconstruction of soft tissue defects after oral cancer surgery with anterolateral thigh flap (ALTF).Methods:Patients who underwent reconstruction of postoperative defects with ALTF in Department of Oral and Maxillofacial Surgery, the Affiliated Stomatological Hospital of Southwest Medical University from January 2013 to January 2020 were retrospectively reviewed. According to the imaging method used for examining perforating artery, all patients were divided into two groups. In group A, CTA and three-dimensional vascular reconstruction were used to locate the lateral femoral circumflex artery and its perforating vessels, and the individualized ALTF was designed. In group B, the lateral circumflex femoral artery and its perforating vessels were located by CDU. The clinical features, operation time, flap survival rate, postoperative complication rate, image quality of angiography, difference of superficial skin points of perforating vessels before and during operation, and diameter of perforators were compared between the two groups. The measurement data were expressed by Mean±SD, and the differences between the two groups were compared by independent sample t-test; paired sample t-test was used to compare the intra-group differences; patients’ clinical features and other enumeration data were expressed in the number of cases (%), and analyzed by chi-square test; reliability analysis was adopted for the image quality score of two doctors at different times, taking Cronbach’s α value; correlations between body mass index (BMI) and flap survival rate were tested by Pearson correlation, whereas the correlation between flap survival rate and underlying diseases, drug combination, bad smoking and drinking habits, and surgical complications were tested by Spearman correlation, which were all performed using SPSS version 20.0 at significance level P<0.05. Results:A total of 50 patients with oral cancer were collected, 25 patients in each group. There were no significant differences between the two groups in clinical features such as sex distribution, age, TNM stage, BMI, underlying diseases, drug combination, bad smoking and drinking habits, tumor location and so on ( P>0.05). The mean operation time of group A was significantly shorter than that of group B[(67.64±5.94) min vs. (70.88±4.88) min, P<0.05]. All flaps in group A survived; one case in group B had complete flap necrosis. There was no significant difference in flap survival rate between the two groups(100% vs. 96%, P>0.05). One case in group A and two cases in group B had complications such as effusion of donor site wound, and there was no significant difference ( P>0.05). Compared with the image quality of the two groups, the angiographic quality score of group A was significantly higher than that of group B, the difference was statistically significant [(3.08±0.64) scores vs. (2.56±0.65) scores, P<0.05]. In group A, the distance difference between the position of the skin superficial point of perforator vessel positioned before operation and during operation was significantly shorter than that in group B, and the difference was statistically significant [(1.32±0.50) mm vs. (1.75±0.84) mm, P<0.05]. In group A, the diameter of perforating artery measured by imaging before operation was (1.68±0.17) mm, which had no significant difference with the actual value[(1.70±0.18) mm] ( P>0.05); whereas, in group B, the diameter of perforating artery measured by imaging before operation was (1.77±0.14) mm. The actual measured value during operation was (1.66±0.15) mm, the difference was statistically significant ( P<0.05). A significant correlation emerged between surgical complications and flap survival rate ( r=0.57, P<0.001), however, there were no significant correlations between BMI, combined with basic diseases, combined medication, bad smoking and drinking habits and flap survival ( P>0.05). Conclusions:Compared with CDU, CTA combined with three-dimensional vascular reconstruction is a feasible and reliable method for preoperative evaluation, flap design. The flap preparation time is shorter. Therefore, it is a good method of preoperative vascular localization.

Objective:To compare the effect of three-dimensional CT angiography (CTA) and color Doppler ultrasound (CDU) in reconstruction of soft tissue defects after oral cancer surgery with anterolateral thigh flap (ALTF).Methods:Patients who underwent reconstruction of postoperative defects with ALTF in Department of Oral and Maxillofacial Surgery, the Affiliated Stomatological Hospital of Southwest Medical University from January 2013 to January 2020 were retrospectively reviewed. According to the imaging method used for examining perforating artery, all patients were divided into two groups. In group A, CTA and three-dimensional vascular reconstruction were used to locate the lateral femoral circumflex artery and its perforating vessels, and the individualized ALTF was designed. In group B, the lateral circumflex femoral artery and its perforating vessels were located by CDU. The clinical features, operation time, flap survival rate, postoperative complication rate, image quality of angiography, difference of superficial skin points of perforating vessels before and during operation, and diameter of perforators were compared between the two groups. The measurement data were expressed by Mean±SD, and the differences between the two groups were compared by independent sample t-test; paired sample t-test was used to compare the intra-group differences; patients’ clinical features and other enumeration data were expressed in the number of cases (%), and analyzed by chi-square test; reliability analysis was adopted for the image quality score of two doctors at different times, taking Cronbach’s α value; correlations between body mass index (BMI) and flap survival rate were tested by Pearson correlation, whereas the correlation between flap survival rate and underlying diseases, drug combination, bad smoking and drinking habits, and surgical complications were tested by Spearman correlation, which were all performed using SPSS version 20.0 at significance level P<0.05. Results:A total of 50 patients with oral cancer were collected, 25 patients in each group. There were no significant differences between the two groups in clinical features such as sex distribution, age, TNM stage, BMI, underlying diseases, drug combination, bad smoking and drinking habits, tumor location and so on ( P>0.05). The mean operation time of group A was significantly shorter than that of group B[(67.64±5.94) min vs. (70.88±4.88) min, P<0.05]. All flaps in group A survived; one case in group B had complete flap necrosis. There was no significant difference in flap survival rate between the two groups(100% vs. 96%, P>0.05). One case in group A and two cases in group B had complications such as effusion of donor site wound, and there was no significant difference ( P>0.05). Compared with the image quality of the two groups, the angiographic quality score of group A was significantly higher than that of group B, the difference was statistically significant [(3.08±0.64) scores vs. (2.56±0.65) scores, P<0.05]. In group A, the distance difference between the position of the skin superficial point of perforator vessel positioned before operation and during operation was significantly shorter than that in group B, and the difference was statistically significant [(1.32±0.50) mm vs. (1.75±0.84) mm, P<0.05]. In group A, the diameter of perforating artery measured by imaging before operation was (1.68±0.17) mm, which had no significant difference with the actual value[(1.70±0.18) mm] ( P>0.05); whereas, in group B, the diameter of perforating artery measured by imaging before operation was (1.77±0.14) mm. The actual measured value during operation was (1.66±0.15) mm, the difference was statistically significant ( P<0.05). A significant correlation emerged between surgical complications and flap survival rate ( r=0.57, P<0.001), however, there were no significant correlations between BMI, combined with basic diseases, combined medication, bad smoking and drinking habits and flap survival ( P>0.05). Conclusions:Compared with CDU, CTA combined with three-dimensional vascular reconstruction is a feasible and reliable method for preoperative evaluation, flap design. The flap preparation time is shorter. Therefore, it is a good method of preoperative vascular localization.

Objective:To explore the effect of the application of mixed reality (MR) technology in clinical teaching of fibular flap preparation.Methods:Twenty residents from the Department of Oral and Maxillofacial Surgery in School of Stomatology, the Fourth Military Medical University in 2018 and 2019 participated in the present study. They were randomly divided into two groups according to the method of random drawing. The teaching content of the two groups was fibular flap preparation. The MR group was taught by using the new teaching mode which was mainly based on MR, while the conventional teaching group was educated by conventional teaching method. At the end of the training, the theoretical knowledge and operational skills of the residents were statistically analyzed to evaluate the learning effect. Questionnaire survey was also conducted. Each item in the questionnaire was scored between 0 and 5, representing poor to excellent.Results:The theoretical scores of MR group (91.4±4.4) were higher than that of the conventional teaching group (83.3±3.2) ( P<0.01). The durations of preoperative marking and simulated osteotomy in MR group [(5.7±1.2) and (20.9±2.28) min, respectively] were shorter than those in the conventional teaching group [(7.2±1.7) and (26.1±3.6) min, respectively] ( P<0.05). The results of the questionnaire showed that MR group had a significant improvement in the scores of classroom atmosphere, satisfaction, three-dimensional construction, theoretical knowledge and problem-solving ability ( P<0.01). However, there was no statistically significant difference in scores of learning concentration between the two groups ( P>0.05). Conclusions:The application of MR technology achieved a better teaching effect, which could help residents to deeply understand the methods of fibular flap preparation, and showed a broad application prospect.

Objective To evaluate the clinical value of holographic image navigation in urological laparoscopic and robotic surgery.Methods The data of patients were reviewed retrospectively for whom accepted holographic image navigation laparoscopic and robotic surgery from Jan.2019 to Dec.2019 in Beijing United Family Hospital and other 18 medical centers,including 78 cases of renal tumor,2 cases of bladder cancer,2 cases of adrenal gland tumor,1 cases of renal cyst,1 case of prostate cancer,1 case of sweat gland carcinoma with lymph node metastasis,1 case of pelvic metastasis after radical cystectomy.All the patients underwent operations.In the laparoscopic surgery group,there were 27 cases of partial nephrectomy,1 case of radical prostatectomy,2 cases of radical cystectomy and 2 cases of adrenalectomy.In the da Vinci robotic surgery group of 54 cases,there were 51 cases of partial nephrectomy,1 case of retroperitoneal lymph node dissection,1 case of retroperitoneal bilateral renal cyst deroofing and 1 case of resection of pelvic metastasis.There were 41 partial nephrectomy patients with available clinical data for statistic,with a median age of 53.5 years (range 24-76),including 26 males and 15 females.The median R.E.N.A.L score was 7.8 (range 4-11).Before the operation,the engineers established the holographic image based on the contrast CT images and reports.The surgeon applied the holographic image for preoperative planning.During the operation,the navigation was achieved by real time fusing holographic images with the laparoscopic surgery images in the screen.Results All the procedures had been complete uneventfully.The holographic images helped surgeon in understanding the visual three-dimension structure and relation of vessels supplying tumor or resection tissue,lymph nodes and nerves.By manipulating the holographic images extracorporeally,the fused image guide surgeons about location vessel,lymph node and other important structure and then facilitate the delicate dissection.For the 41 cases with available clinical data including 23 cases of robotic-assisted partial nephrectomy and 18 cases of laparoscopic nephrectomy,the median operation time was 140 (range 50-225) min,the median warm ischemia time was 23 (range 14-60) min,the median blood loss was 80(range 5-1 200) ml.In the robotic surgery group,the median operation time was 140 (range 50-215)min,the median warm i schemia time was 21 (range 17-40)min,the median blood loss was 150(range 30-1 200)ml.In the laparoscopic surgery group,the median operation time was 160(range 80-225)min,the median warm ischemia time was 25 (range 14-60)min,the median blood loss was 50 (range 5-1 200) ml.All the patients had no adjacent organ injury during operation.There were 2 cases with Clavien Ⅱ complications.One required transfusion and the other one suffered hematoma post-operation.However,the tumors were located in the renal hilus for these 2 cases and the R.E.N.A.L scores were both 11.Conclusions Holographic image navigation can help location and recognize important anatomic structures during the surgical procedures..This technique will reduce the tissue injury,decrease the complications and improve the success rate of surgery.

Objective To evaluate the clinical application and effect of computerized digital sur -gical assisted design and manufacture for reconstruction of mandibular defect with vascularied iliac crest flap graft .Methods CT was used to scan the craniofacial and maxillofacial region of mandibular ameloblastoma patient ,and then the 3D model of the maxillofacial skeleton was reconstructed using the computerized digital surgical aid design to simulate the focal resection and the mandibular defect reconstruction with the iliac crest flap .Surgical guides were prepared by 3D printing to assist focal re-section and bone reshaping .Postoperatively ,clinical and CT examinations were performed to observe the restoration of the patient's facial appearance and occlusal relationship ,as well as wound healing and graft survival .Results Postoperative review results showed that the bone graft survived well ,and the anastomosed bone was formed .The wound in the surgery area healed .No recurrence of the tumor was found after clinical and CT examination .The maxillofacial appearance was well restored ,and the re-sidual occlusal relationship recovered well .Conclusions The use of computerized digital surgical aided design combined with 3D printing technology can effectively simplify the mandibular segmental defect repair and reconstruction and optimize the postoperative repair effect .

Objective To explore the role of computer-aided design and manufacturing technology (CAD/CAM technology) in the repair of mandibular defects using the fibular osteomyocutaneous free flap.Methods Eight patients with a portion of mandible defect due to various reasons were subjected to preoperative CT scan,obtaining CT data of the mandible and the fibular bone to be transplanted.The original and the reconstructed skull model,as well as the mandible and fibula osteotomy guide plates,was printed using CAD/CAM technology.The titanium plates were preformed using the reconstructed skull model,and the operation was performed with the help of guide plates and a preformed titanium plate.The patients were followed up for 6 to 24 months to evaluate the operation effect.Results Two in 8 cases had flap necrosis caused by immune rejection of the implant,and one case had flap necrosis due to poor postoperative blood glucose control.The other 5 patients healed at the primary site and the fibular myocutaneous flap survived well.There were no serious complications in the donor and recepient site.The patients' satisfaction was high.Conclusions The reconstruction of mandible with the aid of CAD/CAM technique has the advantages of accelerating the operation process,shortening the operation time,improving the accuracy of mandibular amputation and fibular shaping,promotlng postoperative function and morphology recovery.

We summarized the epidemiological investigation results of the first case of human infection with avian influenza A(H9N2) virus in Chengdu,China,in order to provide references for dealing with similar diseases scientifically in the future.The methods of field epidemiology and laboratory testing were used to collect the H9N2 case's clinical and epidemiological data,as well as collect and test the samples of the H9N2 case and the relevant environment,so that the possible sources of infection,the epidemiological characteristics and clinical features could be analyzed.Results showed that the H9N2 case contacted with poultry within 10 days before the onset of illness and the H9N2 virus nucleic acid was detected in the patient's specimen by PCR.This case suffered from several chronic diseases for a long time,although active treatments were taken this time,she died soon after onset.Her living environment,the chicken leftovers from cooking,and surrounding poultry markets were polluted by H9 avian influenza virus.Through the investigation,we could deduce that the infection source of this case was the chicken infecting H9N2 viruses from surrounding poultry markets.This would be the first fatality associated with influenza A (H9N2) virus infections in humans.And though avian influenza A(H9N2) virus was low pathogenic,infection could cause severe symptoms or death in people with severe underlying diseases.

Objective To investigate the clinicalmanifestations,imaging features,diagnosis and differential diagnosis,treatment and prognosis of renal malignant solitary fibrous tumor(SFT).Methods The clinical data in 1 case of rare renal malignant SFT were retrospectively analyzed.Referring to related literatures,the histological origin,pathological features,differential diagnosis,treatment and follow-up of renal malignant SFT were analyzed.Results The patient was preoperatively diagnosed as right renal clear cell carcinoma.Postoperative pathological examination diagnosed as low grade malignant SFT of right kidney.And immunohistochemistry indicated CD34+,BCL-2 +,CD68+,CD99+,vimentin,Ki-67 5％ +,SMA focal weakly positive.No recurrence or metastasis occurred after 4-month follow-up period.Conclusion Malignant SFT of the kidney is very rare,its diagnosis and differential diagnosis depend on postoperative pathological and immunohistochemical examination.Radical nephrectomy is the main option for malignant SFT of the kidney with good prognosis.