Analysis of three-dimensional visualization imaging of severe portal vein stenosis after liver transplantation and clinical efficacy of portal vein stent implantation / 器官移植

Objective To analyze three-dimensional imaging characteristics and advantages for severe portal vein stenosis after liver transplantation, and to evaluate clinical efficacy of portal vein stent implantation. Methods Clinical data of 10 patients who received portal vein stent implantation for severe portal vein stenosis after liver transplantation were retrospectively analyzed. Imaging characteristics of severe portal vein stenosis, and advantages of three-dimensional reconstruction imaging and interventional treatment efficacy for severe portal vein stenosis were analyzed. Results Among 10 patients, 3 cases were diagnosed with centripetal stenosis, tortuosity angulation-induced stenosis in 2 cases, compression-induced stenosis in 2 cases, long-segment stenosis and/or vascular occlusion in 3 cases. Three-dimensional reconstruction images possessed advantages in accurate identification of stenosis, identification of stenosis types and measurement of stenosis length. All patients were successfully implanted with portal vein stents. After stent implantation, the diameter of the minimum diameter of portal vein was increased [(6.2±0.9) mm vs. (2.6±1.7) mm, P<0.05], the flow velocity at anastomotic site was decreased [(57±19) cm/s vs. (128±27) cm/s, P<0.05], and the flow velocity at the portal vein adjacent to the liver was increased [(41±6) cm/s vs. (18±6) cm/s, P<0.05]. One patient suffered from intrahepatic hematoma caused by interventional puncture, which was mitigated after conservative observation and treatment. The remaining patients did not experience relevant complications. Conclusions Three-dimensional visualization technique may visually display the location, characteristics and severity of stenosis, which is beneficial for clinicians to make treatment decisions and assist interventional procedures. Timely implantation of portal vein stent may effectively reverse pathological process and improve portal vein blood flow.

Self-expanding Metal Stents in Malignant Obstruction of the Esophagus: A 25-Year Multicentric Study

Background: Self-expanding metal prostheses improve dysphagia in patients with incurable esophageal cancer (EC). New stents have been introduced, and chemoradiotherapy has been implemented for EC, changing patients' risk profiles. It is unknown whether this has affected palliation with stents. Patients and methods: Retrospective study in three centers in Medellín-Colombia; patients undergoing placement of palliative esophageal prostheses for malignant dysphagia (1997-2022). Major and minor complications after implantation, the influence of oncological therapies, and survival were evaluated for 1997-2009 (n = 289) and 2010-2022 (n = 318). Results: 607 patients underwent esophageal prostheses; 296 (48.8%) became complicated. It was higher in the second period (52.5% vs. 48.1%), as were major complications (20.8% vs. 14.2%, p = 0.033), with no differences in minor complications (33.9% vs 31.8%, p = 0.765). Also, 190 (31.3%) patients presented with recurrent dysphagia, stable in both periods. Migration increased over time (from 13.1% to 18.2%, p = 0.09). The most common minor adverse event was pain, increasing over time (from 24.9% to 33.95%, p < 0.01), and associated factors were chemoradiotherapy, absence of fistula, and squamous cell carcinoma. Acid reflux decreased in the second group (p = 0.038). Twelve percent of patients required another intervention for feeding. Survival was not impacted by time and use of stents. Conclusions: Stents are an alternative in non-surgical malignant dysphagia, although recurrent dysphagia has not decreased over time. Minor stent-related complications are increasing in association with the implementation of chemoradiotherapy.

Antecedentes: Las prótesis metálicas autoexpandibles mejoran la disfagia en pacientes con cáncer esofágico (CE) incurable. En las últimas décadas se han introducido nuevos tipos de stents y se ha implementado la quimiorradioterapia para el CE, generando cambios en los perfiles de riesgo de los pacientes. Se desconoce si estos cambios han afectado la paliación con stents. Pacientes y métodos: Estudio retrospectivo en tres centros de Medellín-Colombia; pacientes sometidos a colocación de prótesis esofágicas paliativas para disfagia maligna (1997-2022). Se evaluaron en dos períodos: 1997-2009 (n = 289) y 2010-2022 (n = 318), complicaciones mayores y menores después del implante, la influencia de las terapias oncológicas y la sobrevida. Resultados: Se evaluaron 607 pacientes sometidos a prótesis esofágicas. 296 (48,8%) se complicaron, y fue mayor en el segundo periodo (52,5% frente a 48,1%), al igual que las complicaciones mayores (20,8% frente a 14,2%, p = 0,033), sin diferencias en complicaciones menores (33,9% frente a 31,8%, p = 0,765). 190 (31,3%) pacientes presentaron disfagia recurrente, estable en ambos períodos. La migración aumentó con el tiempo (de 13,1% a 18,2%, p = 0,09). El evento adverso menor más frecuente fue dolor, que aumentó con el tiempo (de 24,9% a 33,95%, p < 0,01), y los factores asociados fueron quimiorradioterapia, ausencia de fístula y carcinoma de células escamosas. El reflujo ácido disminuyó en el segundo grupo (p = 0,038). El 12% de pacientes requirieron otra intervención para alimentarse. No se impactó la sobrevida con el tiempo y uso de stents. Conclusiones: Los stents son una alternativa en la disfagia maligna no quirúrgica, aunque la disfagia recurrente no ha disminuido con el tiempo. Las complicaciones menores relacionadas con el stent van en aumento, asociadas a la implementación de la quimiorradioterapia.

Drainage of Pancreatic Pseudocysts Using Lumen-apposing Metal Stents (LAMS): Experience in Two Referral Centers in Colombia

Introduction: Endoscopic ultrasound (EUS)-guided drainage and luminal-apposing metal stents (LAMS) are the options for managing symptomatic pancreatic pseudocysts. Aim: To evaluate the effectiveness and safety of LAMS for EUS-guided drainage of symptomatic pancreatic pseudocysts in two referral centers in Colombia. Materials and methods: A multicenter prospective cohort study between June 2019 and December 2021 included 13 patients diagnosed with symptomatic pancreatic pseudocysts who underwent EUS-guided drainage with LAMS. Technical success, clinical success, and successful stent removal were evaluated as outcomes. Safety outcomes included stent-related adverse events and general adverse events. Follow-up was carried out for eight weeks, collecting data on stent removal. Results: The average age was 53.4 years; 8/13 were men. The mean size of the pseudocyst was 9.56 ± 2.3 cm. Technical success was 100%, and clinical success was 92.3%. The stents were removed on average after 8 ± 2 weeks. The mean procedural time from puncture to stent deployment was 3.2 ± 2.4 minutes. In the imaging check-up, the collections had adequate drainage in all cases. There was a low frequency of complications; bleeding was documented in one case requiring surgery. Conclusions: LAMS is safe and effective in managing symptomatic pancreatic pseudocysts, reducing hospital stay and cost overruns. Clinical symptomatology prevails in the surgery decision.

Introducción: el drenaje guiado por ultrasonido endoscópico (USE) y el uso de stent metálico luminal de aposición (LAMS) son de elección en el manejo de los pseudoquistes pancreáticos sintomáticos. Objetivo: evaluar la efectividad y seguridad del LAMS para el drenaje por USE de pseudoquistes pancreáticos sintomáticos en dos centros de referencia en Colombia. Materiales y métodos: estudio de cohorte prospectivo multicéntrico entre junio de 2019 y diciembre de 2021, se incluyeron a 13 pacientes con diagnóstico de pseudoquistes pancreáticos sintomáticos sometidos a drenaje por USE con LAMS. Se evaluaron como desenlaces el éxito técnico, el éxito clínico y la extracción exitosa del stent. Y los desenlaces de seguridad incluyeron eventos adversos relacionados con el stent y los eventos adversos generales. Se realizó seguimiento a 8 semanas, en las que se recopilaron datos relacionados con el retiro del stent. Resultados: la edad promedio fue 53,4 años, 8/13 fueron hombres. El tamaño medio del pseudoquiste fue de 9,56 ± 2,3 cm. El éxito técnico fue del 100% y el éxito clínico fue 92,3%. Los stents fueron retirados en promedio a las 8 ± 2 semanas. El tiempo medio del procedimiento desde la punción hasta el despliegue del stent fue 3,2 ± 2,4 minutos. En el control imagenológico hubo un adecuado drenaje de las colecciones en todos los casos. Hubo baja frecuencia de complicaciones, se documentó sangrado en 1 caso con requerimiento quirúrgico. Conclusiones: el uso de LAMS es seguro y efectivo en el manejo de pseudoquistes pancreáticos sintomáticos, disminuye la estancia hospitalaria y sobrecostos. La sintomatología clínica prima en la decisión de intervención.

PREDICTIVE FACTORS OF THE OUTCOME OF EXTRACORPOREAL SHOCKWAVE LITHOTRIPSY FOR UPPER TRACT UROLITHIASIS

Extracorporeal Shock Wave Lithotripsy (ESWL) is one of the treatment options for renal and upper ureteric calculus; however, the outcome depends on multiple factors. Our study aims to evaluate the factors that may inuence ESWL outcomes in Indian patients with upper urinary tract calculi. Between 2018 and 2020, a total of 300 adult patients who underwent ESWL for renal and upper ureteral calculus sizing 5 to 20 mm were included in the study program. Patients with

Non-traumatic esophageal perforation: A case report on Boerhaave’s syndrome

Boerhaave’s syndrome is a potentially fatal condition characterized by spontaneous perforation of a previously healthy esophagus, due to severe vomiting or straining. It often presents with non-specific symptoms such as fever, pain, and vomiting and hence may go undiagnosed. The Makler’s triad, consisting of vomiting, chest pain, and subcutaneous emphysema, may be seen in only 50% of cases. Delayed diagnosis may result in complications such as sepsis, mediastinitis, pneumothorax, and multi-organ dysfunction. In general, patients presenting later than 48 h are conservatively managed with esophageal stenting. Surgical repair is usually reserved for those patients who present within 24 h, or are managed conservatively and develop complications. Mortality rises from 0% if treated within 24 h to about 29% if delayed more than 48 h. We present a case of Boerhaave’s syndrome in a 35-year-old male who presented with spontaneous respiratory distress and hemodynamic instability, about 36 h after the onset of vigorous vomiting. The case was managed initially with endoscopic insertion of a self-expanding metallic stent, followed later by surgical closure of the esophageal perforation. The patient, however, developed post-operative septic complications and died after a week

Effect of pancreatic duct stenting in the treatment of severe acute pancreatitis: a retrospective study in a single center / 中华肝胆外科杂志

Objective:To evaluate the effect of pancreatic duct stenting in the treatment of severe acute pancreatitis (SAP).Methods:The clinical data of 68 patients with SAP admitted to the Department of Hepatobiliary Surgery, General Hospital of Ningxia Medical University from January, 2019 to July, 2020 were retrospectively analyzed, including 38 males and 30 females, aged (44.85±8.51) years old. The patients were divided into two groups according to the treatment modality: the conservative group ( n=41) which received the conservative management, and the stent group ( n=27) which underwent pancreatic duct stent implantation and conservative management. The basic information, parenteral nutrition support time, fasting days, and other clinical data of patients were collected. Serum amylase, white blood cell count, acute physiology and chronic health (APACHE) II score and CT score were compared between the two groups at admission and 48 hours after treatment. Results:The serum amylase, white blood cell count, APACHE II score and CT score of the two groups were significantly lower after treatment (all P<0.05). Compared with the conservative group, the APACHE II score [(5.52±2.15) vs. (8.76±2.50)] and CT score [(4.85±1.96) vs. (6.18±1.07)] of patients were lower in the stent group after treatment (both P<0.05). Pancreatic duct stents were successfully implanted in all 27 patients of the stent group. Intubation to the main pancreatic duct failed in one patient, while the accessory pancreatic duct was alternatively intubated through the accessory nipple. No severe complications such as iatrogenic pancreatitis, bleeding, and perforation occurred after endoscopic retrograde cholangiopancreatography. The incidence of postoperative local complications was lower [18.52%(5/27) vs. 41.46%(17/41)], the proportion of antibiotic use>3 types [29.63%(8/27) vs. 56.10%(23/41)] decreased, and the analgesic episodes decreased [2(1, 3) vs. 4(3, 6)] in the stent group. The antibiotic usage duration [8(3, 11) d vs. 13(10, 19) d], the parenteral nutrition time [7(4, 15)d vs. 15(8, 18)d], the fasting time [5(3, 11) d vs. 11(6, 13)d] and the hospital stay [10(5, 16) d vs. 15(13, 23)d] were all shortened (all P<0.05). Conclusion:Both conservative management and pancreatic duct stenting can alleviate the clinical symptoms of SAP, and pancreatic duct stenting could help reduce local complications, relieve symptoms, and shorten hospital stay.

Analysis of influencing factors on post-treatment in-stent stenosis of intracranial aneurysm using Pipeline embolization device / 中华放射学杂志

Objective:To evaluate the incidence, clinical significance and influencing factors on in-stent stenosis(ISS) after treatment of intracranial aneurysms by Pipeline embolization device(PED).Methods:A retrospective analysis was conducted on the clinical data of 161 patients with intracranial aneurysms treated with PED at the Department of Interventional Radiology of the First Affiliated Hospital of Zhengzhou University from April 2015 to July 2021. PED was implanted into the parent artery through the femoral artery approach after general anesthesia. The first DSA follow-up duration time and imaging data were collected, and the patients were divided into ISS group and non-ISS group accordingly. The degree of aneurysm occlusion was evaluated by O′Kelly-Marotta(OKM) grading scale. Univariate and multivariate logistic regression analysis were applied to identify the factors related to ISS.Results:A total of 179 PED were employed in 161 patients with 168 aneurysms. Eighty-eight (52.38%) aneurysms were treated by PED only, and 80 (47.62%) aneurysms by PED combined with coiling. After a median follow-up of 6 (5, 7) months, 31(18.45%) aneurysms had ISS within the PED, of which 16(9.52%) cases were with mild stenosis (<50%), 13 (7.74%) were with moderate stenosis (50%-75%), and 2(1.19%) were with severe stenosis (>75%). All patients with ISS showed no relevant clinical symptoms. One (0.60%) patient with ISS underwent balloon angioplasty. Univariate analysis showed that the stent diameter, aneurysm location, triglyceride level, the diameter of distal parent artery, and the diameter of proximal parent artery were associated to ISS. Further multivariate logistic regression analysis showed the stent diameter (OR=0.332, 95%CI 0.191-0.578, P<0.001) and triglyceride level (OR=1.641, 95%CI 1.034-2.605, P=0.036) were independent factors of ISS. Conclusions:ISS is a common benign complication after PED treatment. The current results suggest that small stent diameter and high triglyceride level are independent factors of ISS.

Analysis of the status and risk factors of in stent restenosis in patients with acute myocardial infarction and diabetes mellitus one year after percutaneous coronary intervention / 中国医师杂志

Objective:To analyze the status of in stent restenosis (ISR) in patients with acute myocardial infarction (AMI) and diabetes mellitus (DM) one year after percutaneous coronary intervention (PCI), and explore the risk factors.Methods:From December 2019 to December 2020, 158 patients with AMI and DM who were treated by PCI in Qionghai Hospital of Traditional Chinese Medicine and the First Affiliated Hospital of Hainan Medical College were selected. They were followed up for one year after surgery to calculate the incidence of ISR. The patients were divided into ISR group and non ISR group according to whether ISR occurred. The difference of clinical data between the two groups was compared. Logistic regression was used to analyze the risk factors for the occurrence of ISR in AMI patients with DM 1 year after PCI.Results:55 patients were followed up for 1 year, and the incidence of ISR was 34.81% (55/158). There were significant difference between ISR group and non ISR group in hypertension history, old myocardial infarction history, smoking, exercise ratio, preoperative low density lipoprotein cholesterol (LDL-C), total bilirubin (TBIL), blood uric acid (UA), plasma fibrinogen (FIB), glycosylated hemoglobin (HbA 1c) levels, coronary artery lesion number, stenosis degree, stent length, stent diameter (all P<0.05). Multivariate logistic regression analysis showed that hypertension history, smoking, LDL-C, FIB, HbA 1c and stent length were independent risk factors for ISR in AMI patients with DM after PCI, and exercise and appropriate increase of stent diameter were protective factors (all P<0.05). Conclusions:The incidence of ISR in AMI patients with DM at 1 year after PCI is relatively high, and its occurrence is related to many factors. In order to reduce the risk of ISR after PCI, we should encourage smoking cessation, exercise, strengthen the monitoring of biochemical indicators, and appropriately increase the diameter of stent during PCI.

Application of ureteral stent in kidney transplantation / 器官移植

Ureteral stricture, urine leakage and other urinary complications are likely to occur after kidney transplantation, which severely affect the function of renal allograft and even lead to renal allograft loss. Ureteral stent plays a critical role in kidney transplantation, which could promote the urine flow from kidney to bladder after kidney transplantation, lower the pressure within the ureter and reduce the risk of early urinary complications. However, it may also cause urinary tract infection, stent-related complications and BK virus infection, etc. Therefore, clinicians should flexibly grasp the indications for ureteral stent removal. In this article, the application, potential adverse reactions and the timing of removal of ureteral stent in the field of kidney transplantation were reviewed, aiming to provide reference for clinical decision-making related to ureteral stent after kidney transplantation.

Research progress on anhepatic phase in rat liver transplantation / 器官移植

With persistent advancement of surgical instruments, methods and techniques, clinical efficacy of liver transplantation has been steadily enhanced. However, the length of anhepatic phase is still an important factor affecting the efficacy of liver transplantation. Rat is one of the major animal models for liver transplantation-related basic research. In this article, multiple approaches for prolonging the anhepatic phase and shortening the operation time during anhepatic phase in rat liver transplantation were reviewed, which consisted of sevoflurane inhalation anesthesia, intravenous infusion via jugular vein indwelling needle, clamping of the abdominal aorta before anhepatic phase, injection of normal saline into portal vein before anhepatic phase, subcutaneous transposition of the spleen, electrocoagulation of hepatic esophageal artery, magnetic ring anastomosis of the superior and inferior hepatic vena cava, cannula anastomosis of the superior and inferior hepatic vena cava, stent anastomosis of the superior and inferior hepatic vena cava, rapid connection device and cannula of portal vein, and ring-shaped cannula of hepatic tissue-preserving inferior hepatic vena cava, aiming to add evidence for prolonging the duration of anhepatic phase, improving the operation efficiency during anhepatic phase and elevating the success rate of rat liver transplantation.

Predictive value of controlled nutritional status score for overt hepatic encephalopathy after transjugular intrahepatic portosystemic stent-shunt of Budd-Chiari syndrome / 中华消化外科杂志

Objective:To investigate the predictive value of controlled nutritional status (CONUT) score for overt hepatic encephalopathy (OHE) after transjugular intrahepatic portosys-temic stent-shunt (TIPSS) in Budd-Chiari syndrome patients.Method:The retrospective case-control study was conducted. The clinicopathological data of 48 Budd-Chiari syndrome patients who underwent TIPSS in the First Affiliated Hospital of Zhengzhou University from August 2014 to March 2021 were collected. There were 26 males and 22 females, aged (46±13)years. Observation indicators: (1) surgical situations and follow-up; (2) analysis of influencing factors of OHE after TIPSS; (3) predic-tion of OHE after TIPSS. Measurement data with normal distribution were represented as Mean± SD, and comparison between groups was performed using the t test. Measurement data with skewed distribution were represented by M( Q1, Q3), and comparison between groups was performed using the Mann-Whitney U test. Count data were expressed as absolute numbers or percentages, and comparison between groups was performed using the chi-square test or Fisher exact probability. Multivariate analysis was performed using the Logistic regression model with forward method. The receiver operating characteristic (ROC) curve was drawn and the area under the curve (AUC) was calculated to evaluate the efficacy. Comparison among AUC was performed using the Delong test. Results:(1) Surgical situations and follow-up. All 48 patients underwent TIPSS successfully, and the operation time of the 48 patients was (131±29)minutes. All patients were implanted with 8 mm covered stent. All 48 patients were followed up for 46(25,71)months, and there were 14 cases with OHE and 34 cases without OHE after TIPSS. Of the 14 cases with OHE, 12 cases were evaluated as West-Haven Ⅱ grade and 2 cases were evaluated as West-Haven Ⅲ grade. (2) Analysis of influencing factors of OHE after TIPSS. Results of multivariate analysis showed that history of hepatic encephalo-pathy and CONUT score were independent factors influencing the incidence of OHE of Budd-Chiari syndrome patients who underwent TIPSS ( odds ratio=8.36, 1.74, 95% confidence interval as 1.02?68.75, 1.12?2.69, P<0.05). (3) Prediction of OHE after TIPSS. Results of ROC curve showed that the AUC of the CONUT score, the Child-Pugh score of liver function and the integrated model of end-stage liver disease (iMELD) score in predicting the incidence of OHE after TIPSS was 0.77(95% confidence interval as 0.64?0.91, P<0.05), 0.71(95% confidence interval as 0.56?0.87, P<0.05) and 0.71(95% confidence interval as 0.53?0.88, P<0.05), respectively, and there was no significant difference between the AUC of the CONUT score and the Child-Pugh score of liver function or the iMELD score ( Z=0.84, 0.59, P>0.05). The optimal cutoff value of CONUT score in predicting the incidence of OHE after TIPSS was 7, with the sensitivity, specificity and Yodon index as 78.6%, 61.8% and 0.40, respectively. Conclusion:The CONUT score can be used to predict the incidence of OHE in Budd-Chiari syndrome patients who underwent TIPSS, and the discrimination of CONUT score is equivalent to the Child-Pugh score of liver function and the iMELD score.

Observation on the efficacy of different stents in the treatment of patients with advanced esophageal cancer / 国际肿瘤学杂志

Objective:To explore the efficacy and safety of treating advanced esophageal cancer by implanting the common stent and the radioactive 125I particle stent with endoscope. Methods:The clinical data of patients with advanced esophageal cancer admitted to Jingbian County People's Hospital of Shaanxi Province, the First Affiliated Hospital of Xi'an Medical University, Xijing Hospital of Digestive Diseases of Air Force Medical University and the First Hospital of Yulin of Shaanxi Province from December 2014 to December 2020 were retrospectively analyzed. Patients were divided into common stent group ( n=66) and radioactive particle stent group ( n=34) according to different stent types. The postoperative complications, Karnofsky performance status (KPS) score, dysphagia score, restenosis rate and quality of life were compared between the two groups. Results:The incidences of postoperative retrosternal pain in the common stent group and the radioactive particle stent group were 65.2% (43/66) and 47.1% (16/34) respectively. The incidences of pharyngeal pain and hoarseness were 12.1% (8/66) and 5.9% (2/34) . The incidences of abdominal pain were 9.1% (6/66) and 2.9% (1/34) . The incidences of errhysis were 3.0% (2/66) and 2.9% (1/34) . The incidences of vomiting and nausea were 7.6% (5/66) and 5.9% (2/34) respectively. There were no statistically significant differences between the two groups ( χ2=3.04, P=0.081; χ2=0.40, P=0.527; χ2=0.53, P=0.467; χ2<0.01, P>0.999; χ2<0.01, P>0.999) . In the two groups, KPS scores in the first, second, third and sixth month after operation were higher than those before operation (all P<0.05) . KPS scores of the radioactive particle stent group in the second, third and sixth month were significantly higher than those of the common stent group [ (89.73±7.84) points vs. (82.37±7.42) points, t=4.62, P<0.001; (93.63±8.13) points vs. (88.33±7.28) points, t=3.74, P<0.001; (92.78±6.26) points vs. (87.28±8.73) points, t=3.77, P<0.001]. The dysphagia scores of patients in the two groups in the first, second, third and sixth month were lower than those before operation (all P<0.05) . The dysphagia scores of the radioactive particle stent group in the third and sixth month after operation were significantly lower than those of the common stent group [ (0.68±0.12) points vs. (2.33±0.32) points, t=26.20, P<0.001; (0.82±0.22) points vs. (2.67±0.24) points, t=36.92, P<0.001]. In the third month after operation, the restenosis rate of the radioactive particle stent group was significantly lower than that of the common stent group [5.88% (2/34) vs. 42.4% (28/66) , χ2 =14.27, P<0.001]. The scores of QLQ-C30 and OES-18 scales in the first, second, third and sixth month after operation were lower than those before operation (all P<0.05) . The scores of QLQ-30 scale in the radioactive particle stent group in the second, third and sixth month were significantly lower than those in the common stent group [ (19.12±3.02) points vs. (21.22±2.87) points, t=3.39, P=0.001; (15.04±1.68) points vs. (20.43±2.23) points, t=12.39, P<0.001; (14.38±2.18) points vs. (19.77±3.67) points, t=9.20, P<0.001]. The scores of OES-18 scale in the radioactive particle stent group were also significantly lower than those in the common stent group [ (17.13±2.07) points vs. (20.64±2.11) points, t=7.95, P<0.001; (15.22±1.88) points vs. (19.24±1.76) points, t=10.62, P<0.001; (14.74±2.36) points vs. (18.53±3.27) points, t=6.01, P<0.001]. Conclusion:The radioactive particle stent can improve the quality of life of patients with advanced esophageal cancer with esophageal stenosis, so as to improve dysphagia and reduce the restenosis rate after operation. However, whether it is obviously superior to common stent in prolonging survival time and reducing complications needs to be further confirmed by a multicenter, prospective, large-sample randomized controlled study.

Effect of Quercus Salicina Extract Capsules on preventing adherent stones on ureteral stent tube after percutaneous nephrolithotomy / 国际外科学杂志

Objective:To explore the effect of Quercus Salicina Extract Capsulese on preventing the formation of adherent stones on ureteral stent tube after percutaneous nephrolithotomy (PCNL).Methods:The clinical data of 186 patients who underwent PCNL due to unilateral renal stone in the Affiliated Hospital of Xuzhou Medical University from October 2018 to April 2020 were retrospectively analyzed. All of the patients were indwelling 6 F ureteral stent tube during operation. After postoperative reexamination of kidneys, ureters and bladder, it was confirmed that the postoperative residual stones were clinically meaningless stones (maximum diameter ≤ 4 mm). According to postoperative medication, they were divided into drug group ( n=62) and control group ( n=124). Patients in the drug group were given oral Quercus Salicina Extract Capsules, while patients in the control group did not take the drug. Both groups received the same health education and dietary guidance after operation. The formation of adherent stones on ureteral stent tube was observed when the ureteral stent tube was removed 6 weeks after PCNL. Meanwhile, the adverse reaction, complication and treatment satisfaction of the patients were recorded during the period of taking the drug. Measurement data were expressed as mean ± standard deviation ( ± s), and t-test was used for comparison between groups; the Chi-square test was used to compare the count data between groups. Results:When the ureteral stent tube was removed 6 weeks after PCNL, the weight of adherent stones on ureteral stent tube in the drug group was (334.20±26.65) mg for male, and (336.00±25.64) mg for female. In the control group, the weight of adherent stones on ureteral stent tube was (374.11±42.28) mg for male, (374.42±42.44) mg for female. The weight of adherent stones on ureteral stent tube in the drug group was significantly lighter than that in the control group, and the difference was statistically significant ( P<0.01). The drug group had no obvious serious adverse reaction during the period of taking the drug. At the same time, the complications of the drug group during the intubation period were significantly less than the control group, and the difference was statistically significant ( P=0.040). The satisfaction of patients in the drug group was 93.5%, and that in the control group was 82.3%. The difference was statistically significant between the two groups ( P=0.036). Conclusion:Quercus Salicina Extract Capsules can effectively prevent the occurrence of adherent stones on ureteral stent tube after PCNL, and there are no serious adverse reaction, which is worthy of clinical promotion.

Mechanical Behavior of Radial Support of a Novel Balloon Expandable Tapered Stent / 医用生物力学

Objective To explore influences of the taper and connecting rib form on supporting performance of the stent, and provide an important scientific basis for structural design and clinical selection of the tapered stent. Methods A nonlinear finite element model for radial support performance of a novel balloon-expandable tapered stent was constructed, and the radial stiffness (RS) and stress distributions of the stent at different tapers (0°, 0.565°and 1.13°) and with different structural forms of stent linker (V-shape, I-shape, C-shape, S-shape, M-shape) were analyzed by plane compression. The relationship between structural design of the vascular stent and its radial support performance was studied. Results The RS of 0°stent, 0.565°stent, 1.13° stent was 2.51, 1.61, 0.85 N/mm, respectively. The RS of 0.565°stent and 1.13° stent was 35.86% and 66.14% lower than that of 0°stent (round straight stent), respectively. Except that the RS of C-shape linker stent was 1.48 N/mm, the RS of I, M, S and V-shape linker stents was not significantly different, which was 2.51, 2.61, 2.41, 2.52 N/mm, respectively, indicating that radial compression resistance of these four linker stents was almost the same. Conclusions Compared with traditional round straight stents, the RS of tapered stents will decrease, and the RS of stents will gradually decrease with the the taper increasing. Among all stent types in this study, except C-shape linker stents, the RS of other linker shapes has little effect on the RS of stents. The radial support performance of the stent can be improved by reducing the taper of the tapered stent, without changing the form of stent connecting ribs.

Finite Element Simulation of Double-Stent Parallel Thrombectomy at Y-Shaped Bifurcation of Internal Carotid Artery / 医用生物力学

Objective To study the process of single stent and double-stent thrombectomy at the Y-shaped bifurcation of the ideal internal carotid artery by finite element simulation, analyze the stent-thrombus-vessel interaction during the thrombectomy process based on the simulation results, and provide guidance for improving the effect of stent thrombectomy at the bifurcation. Methods The CAD software was used to build the model and the finite element analysis software was used to simulate the process of single stent and double-stent thrombectomy. Results Thrombectomy was unsuccessful in single stent model and successful in double-stent model, and the maximum stress of thrombus during embolus retrieval was twice that of single stent, the maximum strain was 1.12 times that of single stent, and the maximum contact pressure on the surface of vessel was approximately twice that of single stent. Conclusions Double Solitaire stents can effectively prevent thrombus displacement at the bifurcation and successfully retrieve the thrombus, but there is a risk of fracture due to the high stress level in the middle section of the thrombus. The contact pressure of the vessel on the anterior artery side is higher during thrombectomy, and the risk of vessel damage is greater. Therefore, it is necessary to optimize the design of the stent-retriever to improve its flexibility.

Progress in self-expanding metallic ureteral stent in the treatment of ureteral stricture in renal allografts / 器官移植

Ureteral stricture in renal allografts is one of the common postoperative complications in kidney transplant recipients. Due to short ureter in renal allografts, endovascular treatment should be adopted before reconstruction surgery to avoid irreversible injury. Alleviating renal allograft injury, easing obstruction or establishing drainage channel are the key measures to treat ureteral stricture. In endovascular treatment, balloon dilatation and internal incision yield high recurrence rate, and long-term indwelling of self-expanding metallic ureteral stents may be a better option. Compared with traditional stents, metallic stents may maintain urinary tract patency for a long time and mitigate the irritation of lower urinary tract symptoms,with different indications and efficacy. Although all metallic stents may be displaced and occluded, it still plays a positive role in the treatment of ureteral stricture in renal allografts. In this article, the application of self-expanding metallic ureteral stent in ureteral stricture of renal allografts was mainly illustrated, aiming to provide reference for optimizing the treatment of ureteral stricture in renal allografts.

A Case of Innominate Artery Transection after the Covered Stent Placement for the Recurrent Tracheo-Innominate Artery Fistula / 日本心臓血管外科学会雑誌

Tracheo-Innominate artery fistula is a rare but devastating complication after tracheostomy. We report a 17-year old man who underwent the transection of the innominate artery and tracheal patch closure (under partial sternotomy) after the endovascular covered stent placement for the recurrent tracheo-innominate artery fistula. Fortunately, his postoperative course was uneventful without any new neurological, bleeding, or infective complication 34 months after the surgery.

A Case of Effective Zone 0 TEVAR Using Squid-Capture Assisted in situ Stent-Graft Fenestration, for Endoleak from the Fenestration of Najuta / 日本心臓血管外科学会雑誌

We report the case of a 76-year-old man who developed type IA endoleak through the fenestration after 1-debranch TEVAR using a Najuta endograft. The patient was admitted with expansion of the aneurysm after TEVAR, for additional therapy. Type IA endoleak through a fenestration has remained a significant clinical concern and its treatment is challenging. We performed Zone 0 TEVAR using the “Squid-Capture” technique assisted in situ stent-graft fenestration. Cerebral vessels were perfused by a percutaneous cardiopulmonary support system during in situ stent-graft fenestration, and the cerebral branch was clamped at the proximal site. It is difficult to operate the catheter inside the endoskeleton structure of a Najuta endograft, but several innovations were effective. Test dilation of the balloon catheter was performed to ensure that the wire did not interfere with the endoskeleton. Avoiding interference with the endoskeleton is important. The Squid-Capture technique allows safe and secure puncture of the graft. The operation was completed successfully. After this procedure, the endoleak disappeared. It is considered to be a useful method for treatment of endoleak through the fenestration.

Efficacy of glucocorticoid stent implantation in ethmoid sinus after endoscopic sinus surgery for chronic rhinosinusitis with nasal polyps / 临床耳鼻咽喉头颈外科杂志

Objective:To evaluate the efficacy of glucocorticoid sinus stents implanted 2 weeks after functional endoscopic sinus surgery（FESS） for the treatment of chronic rhinosinusitis with nasal polyps（CRSwNP）. Methods:CRSwNP patients with similar bilateral lesions were randomly divided into two groups, with a stent group of 25 patients and a control group of 24 patients. Patients in the stent group had glucocorticoid sinus stents implanted into the bilateral ethmoid sinuses 2 weeks after FESS, while the control group underwent postoperative debridement only. Follow-up assessments occurred at postoperative weeks 2, 4, 8, and 12. Patients were asked to assess their sensation of nasal symptoms using a 10-point visual analog scale. Efficacy was assessed by endoscopic evaluations. Sinus obstruction, crusting/coagulation, polyp formation, middle turbinate position, adhesions, mucosa epithelialization, and postoperative intervention were assessed as efficacy outcomes. GraphPad Prism 9 was applied for statistical analysis. Results:At 4 and 8 weeks postoperatively, the stent group showed significant improvement in VAS scores of nasal congestion and runny nose compared with the control group（P<0.05）. No significant difference was observed in the VAS scores of head and facial stuffiness, loss of smell, or nasal dryness/crusting between the two groups（P>0.05）. Compared with the control group, the stent group had a lower rate of polypoid formation at 4, 8, and 12 weeks postoperatively. At postoperative week 12, the rate of mucosal epithelialization in the ethmoid cavity was significantly higher in the stent group. During the follow-up, the frequency of postoperative intervention was significantly lower in the stent group than in the control group（P<0.05）. Besides, a lower incidence of middle turbinate lateralization was found in the stent group at 8 and 12 weeks postoperatively. At 8 weeks postoperatively, the stent group had a percentage of adhesion lower than that of the control group（all P<0.05）. Conclusion:Implantation of glucocorticoid sinus stents after FESS can maintain sinus cavity patency, improve the inflammatory status of the operative cavity, reduce postoperative interventions, and promote benign regression of the operative cavity.

Three-dimensional printed 316L stainless steel cardiovascular stent's electrolytic polishing and its mechanical properties / 生物医学工程学杂志

The interventional therapy of vascular stent implantation is a popular treatment method for cardiovascular stenosis and blockage. However, traditional stent manufacturing methods such as laser cutting are complex and cannot easily manufacture complex structures such as bifurcated stents, while three-dimensional (3D) printing technology provides a new method for manufacturing stents with complex structure and personalized designs. In this paper, a cardiovascular stent was designed, and printed using selective laser melting technology and 316L stainless steel powder of 0-10 µm size. Electrolytic polishing was performed to improve the surface quality of the printed vascular stent, and the expansion behavior of the polished stent was assessed by balloon inflation. The results showed that the newly designed cardiovascular stent could be manufactured by 3D printing technology. Electrolytic polishing removed the attached powder and reduced the surface roughness Ra from 1.36 µm to 0.82 µm. The axial shortening rate of the polished bracket was 4.23% when the outside diameter was expanded from 2.42 mm to 3.63 mm under the pressure of the balloon, and the radial rebound rate was 2.48% after unloading. The radial force of polished stent was 8.32 N. The 3D printed vascular stent can remove the surface powder through electrolytic polishing to improve the surface quality, and show good dilatation performance and radial support performance, which provides a reference for the practical application of 3D printed vascular stent.