ObjectiveTo investigate the clinical features of patients with acute-on-chronic liver failure （ACLF） and bacterial infection and early warning indicators associated with multidrug-resistant infections. MethodsA retrospective analysis was performed for 130 patients with ACLF and bacterial infection who attended The Second Affiliated Hospital of Air Force Medical University from January 1， 2010 to December 31， 2021， and according to the drug susceptibility results， the patients were divided into multidrug-resistant （MDR） bacterial infection group with 80 patients and non-MDR bacterial infection group with 50 patients. General information and laboratory examination results were compared between the two groups to screen for the early warning indicators associated with MDR bacterial infection. The Student’s t-test was used for comparison of normally distributed continuous data with homogeneity of variance between two groups， and the Mann-Whitney U test was used for comparison of non-normally distributed continuous data or continuous data with heterogeneity of variance between two groups； the chi-square test or the Fisher’s exact test was used for comparison of categorical data between two groups. The binary logistic regression analysis and the receiver operating characteristic （ROC） curve were used to assess the predictive value of early warning indicators. ResultsAmong the 130 patients with ACLF and bacterial infection， sputum （27.7%） was the most common specimen for detection， followed by blood （24.6%）， urine （18.5%）， and ascites （17.7%）. Bacterial infections were dominated by Gram-negative bacteria （58.5%）. Of all bacteria， Escherichia coli （18.5%）， Klebsiella pneumoniae （14.6%）， and Enterococcus faecium （13.8%） were the most common pathogens. Gram-positive bacteria had a high resistance rate to the antibacterial drugs such as erythromycin （72.2%）， penicillin （57.4%）， ampicillin （55.6%）， and ciprofloxacin （53.7%）， while Gram-negative bacteria had a high resistance rate to the antibacterial drugs such as ampicillin （73.3%）， cefazolin （50.0%）， and cefepime （47.4%）. The patients with ACLF and bacterial infection had a relatively high rate of MDR bacterial infection （61.5%）. Comparison of clinical data between the two groups showed that compared with the patients with non-MDR bacterial infection， the patients with MDR bacterial infection had significantly higher levels of alanine aminotransferase （Z=2.089， P=0.037）， aspartate aminotransferase （Z=2.063， P=0.039）， white blood cell count （Z=2.207， P=0.027）， and monocyte count （Z=4.413， P<0.001）. The binary logistic regression analysis showed that monocyte count was an independent risk factor for MDR bacterial infection （odds ratio=7.120， 95% confidence interval ［CI］： 2.478‍ ‍—‍ ‍20.456，P<0.001） and had an area under the ROC curve of 0.686 （95%CI： 0.597‍ ‍—‍ ‍0.776） in predicting ACLF with MDR bacterial infection（P<0.001）， with the optimal cut-off value of 0.50×10⁹/L， a sensitivity of 0.725， and a specificity of 0.400. ConclusionACLF combined with bacterial infections is mainly caused by Gram-negative bacteria， with the common pathogens of Escherichia coli and Klebsiella pneumoniae and a relatively high MDR rate in clinical practice. An increase in monocyte count can be used as an early warning indicator to distinguish MDR bacterial infection from non-MDR bacterial infection.

Objective To compare the safety and efficacy of direct thrombectomy versus bridging thrombectomy in the treatment of acute anterior circulation large vessel occlusion stroke under different collateral circulation statuses.Methods Totally 93 patients with acute anterior circulation ischemic stroke admitted to the First Affiliated Hospital of Xinxiang Medical University from September 2020 to March 2023 were selected as the research subjects.Patients were divided into direct throm-bectomy group(n=47)and bridging thrombectomy group(n=46)based on the type of thrombectomy.Patients in the direct thrombectomy group received direct intravascular thrombectomy,while patients in the bridging thrombectomy group received intravenous thrombolysis with alteplase combined with mechanical thrombectomy.According computed tomography angiography,the collateral circulation Tan classification was applied to divide the patients into good collateral circulation sub-group and poor collateral circulation sub-group.The modified thrombolysis in cerebral infarction grading(mTICI)was used to evaluate vessel recanalization.Head computed tomography plain scan was performed at 24-48 hours postoperatively to assess if there was hemorrhagic transformation,and modified Rankin Scale score was performed at 90 days postoperatively.Information such as imaging examination time,femoral artery puncture time,vessel recanalization time after thrombectomy,prognosis and spontaneous non-traumatic symptomatic intracerebral hemorrhage(SICH)were collected.Results The age,gender,baseline Alberta stroke program early computed tomography score,baseline national institutes of health stroke scale score,proportions of hypertension,diabetes and atrial fibrillation,baseline systolic pressure,creatinine,baseline blood glucose,platelet count,occlusion site,stroke etiologies and collateral circulation status of patients in the two groups were not statistically significantly different(P＞0.05).There were no significant differences in the post-admission imaging examination time,femoral artery puncture time,vessel recanalization time after thrombectomy,successful vascular reperfusion rate,good prognosis rate,mortality rate,and SICH incidence between the two groups(P＞0.05).The hemorrhagic transformation rate of patients in the direct thrombectomy group was significantly lower than that in the bridging thrombectomy group(P＜0.05).There were no significant differences in the post-admission imaging examination time,femoral artery puncture time,vessel recanalization time after thrombectomy,successful vascular reperfusion rate,good prognosis rate,mortality rate,and SICH incidence between patients with good collateral circulation and patients with poor collateral circulation in the two groups(P＞0.05).The hemorrhagic transformation rate of patients with good and poor collateral circulation in the direct thrombectomy group was significantly lower than that in the bridging thrombectomy group(P＜0.05).Conclusion Under different collateral circulation conditions,the safety and efficacy of direct thrombectomy and bridging thrombectomy in the treatment of acute anterior circulation large vessel occlusion stroke are similar,but bridging thrombectomy is more likely to result in cerebral hemorrhage transformation compared with direct thrombectomy.

Objective To explore the relationship between collateral circulation and the prognosis of acute ischemic stroke(AIS)patients with successful recanalization after mechanical thrombectomy.Methods A total of 75 AIS patients who received mechanical thrombectomy at the First Affiliated Hospital of Xinxiang Medical University from September 2020 to May 2022 were selected as the research subjects.The clinical data of the patients were collected.According to the modified Rankin scale(mRS)score at 90 days after operation,the patients were divided into the good prognosis group(mRS score≤2)and the poor prognosis group(mRS score ≥3).Univariate and multivariate logistic regression were used to analyze the factors affecting the prognosis of AIS patients with successful recanalization after mechanical thrombectomy.There were three types of collateral circulation:symmetrical collateral circulation,malignant collateral circulation,and other collateral circulation.The National Institutes of Health Stroke Scale(NIHSS)score at admission,the NIHSS score at discharge and changes of the NIHSS score of patients with different collateral circulations were compared.Results Among the 75 patients,43 had a good prognosis,and 32 had a poor prognosis.The incidence of poor prognosis was 42.67％.Univariate analysis showed that history of diabetes,time from onset to puncture(OPT),collateral circulation and NIHSS score were the factors effecting the prognosis of AIS patients with successful recanalization after mechanical thrombectomy(P＜0.05).Age,sex,history of atrial fibrillation,history of hypertension,history of smoking,history of stroke,thrombolytic therapy and modified thrombolysis in cerebral infarction grade were not related to the prognosis of AIS patients with successful recanalization after mechanical thrombectomy(P＞0.05).Multivariate logistic regression analysis showed that symmetrical collateral circulation,malignant collateral circulation,history of diabetes and OPT were independent influencing factors for the prognosis of AIS patients with successful recanalization after mechanical thrombectomy(P＜0.05).There was no significant difference in the admission NIHSS score among the patients with different collateral circulations(P＞0.05).The discharge NIHSS score of patients with symmetrical collateral circulation was significantly lower than that of patients with malignant collateral circulation,and the change in the NIHSS score was more significant than that of patients with malignant collateral circulation(P＜0.05).There was no significant difference in the discharge NIHSS score and change in the NIHSS score between patients with symmetrical collateral circulation and patients with other collateral circulation(P＞0.05),and between patients with malignant collateral circulation and patients with other collateral circulation(P＞0.05).Conclusion Symmetrical collateral circulation,malignant collateral circulation are independent factor affecting the prognosis of AIS patients with successful recanalization after mechanical thrombectomy.Symmetrical collateral circulation may help improve the neurological function of patients after mechanical thrombectomy,and malignant collateral circulation may lead to deterioration of neurological function in patients undergoing mechanical thrombectomy.

ObjectiveTo determine the mechanism of Yitangkang in correcting excessive apoptosis of skeletal muscle cells to improve insulin resistance （IR） by inhibiting the advanced glycation end product （AGE）/receptor for the advanced glycation end product （RAGE） signaling pathway. Method① In vitro experiments. Yitangkang-medicated serum was prepared. C2C12 cells were divided into a blank group， a model group， high-， medium-， and low-dose Yitangkang-medicated serum groups （40， 20， and 10 g·kg^-1）， and a RAGE inhibitor group. The IR model was induced by palmitic acid in C2C12 cells except for those in the blank group. After the corresponding intervention methods were conducted，the cell viability and glucose consumption level of each group were determined. In addition，the apoptosis rate was determined using flow cytometry. The mRNA and protein expression levels of the important apoptotic proteins ［B-cell lymphoma 2 （Bcl-2）， Bcl-2-associated X protein （Bax）， p53， cysteinyl aspartate-specific protease-3 （Caspase-3）， and cysteinyl aspartate-specific protease-9 （Caspase-9）］ were determined using Real-time fluorescence quantitative polymerase chain reaction （Real-time PCR） and Western blot. ② In vivo experiments. Ninety-six eligible Wistar rats were divided into a blank group， a model group， high-，medium-，and low-dose Yitangkang groups （40， 20， and 10 g·kg^-1）， and a western medicine group （pioglitazone hydrochloride，1.35 mg·kg^-1）. The IR model was induced using high-glucose and high-fat feed for diabetes combined with intraperitoneal injection of low-dose streptozotocin （STZ） in animals and verified by the hyperinsulinemic-euglycemic clamp （HEC） test. After the model was determined successfully， the rats in each group were given intragastric administration of drugs as required. Terminal deoxynucleotidyl transferase dUTP nick end labeling （TUNEL） assay was performed to determine the number of positive apoptotic cells in the skeletal muscle tissues of rats in each group，while Real-time polymerase chain reaction（Real-time PCR） and Western blot were performed to determine the mRNA and protein expression levels of the important apoptotic proteins Bcl-2， Bax， p53， Caspase-3， and Caspase-9. Result① In vitro experiments. compared with the blank group， the model groups showed increased apoptosis rate of C2C12 cells and decreased cell viability and glucose consumption （P<0.01）. Compared with the model group， the Yitangkang-medicated serum groups and the RAGE inhibitor group showed decreased apoptosis rate of C2C12 cells and increased cell viability and glucose consumption （P<0.01）. Compared with the blank group， the model group showed decreased expression levels of Bcl-2 mRNA and protein in C2C12 cells and increased mRNA and protein expression levels of Bax， p53， Caspase-3， and Caspase-9 （P<0.01）. Compared with the model group， the Yitangkang-medicated serum groups and the RAGE inhibitor group showed increased expression levels of Bcl-2 mRNA and protein in C2C12 cells （P<0.01） and decreased mRNA and protein expression levels of Bax， p53， Caspase-3， and Caspase-9 （P<0.05， P<0.01）. ② In vivo experiments. The number of positive apoptotic cells in the skeletal muscle tissues of rats in the model group significantly increased as compared with that in the blank group （P<0.01）. The number of positive apoptotic cells in the skeletal muscle tissues of rats in the Yitangkang groups and the western medicine group decreased as compared with that in the model group （P<0.01）. Compared with the blank group， the model group showed decreased expression levels of Bcl-2 mRNA and protein in skeletal muscle tissues of rats and increased mRNA and protein expression levels of Bax， p53， Caspase-3， and Caspase-9 （P<0.01）. Compared with the model group， the Yitangkang groups and the western medicine group showed increased expression levels of Bcl-2 mRNA and protein in skeletal muscle tissues of rats （P<0.01） and decreased mRNA and protein expression levels of Bax， p53， Caspase-3， and Caspase-9 （P<0.05， P<0.01）. The medium-dose Yitangkang showed a similar effect as RAGE inhibitor， and the effect was equivalent to that of pioglitazone hydrochloride. ConclusionYitangkang can inhibit skeletal muscle cell apoptosis by inhibiting the AGE/RAGE signaling pathway.

Hepatocellular carcinoma (HCC) is the most common liver malignancy, where HCC segmentation and prediction of the degree of pathological differentiation are two important tasks in surgical treatment and prognosis evaluation. Existing methods usually solve these two problems independently without considering the correlation of the two tasks. In this paper, we propose a multi-task learning model that aims to accomplish the segmentation task and classification task simultaneously. The model consists of a segmentation subnet and a classification subnet. A multi-scale feature fusion method is proposed in the classification subnet to improve the classification accuracy, and a boundary-aware attention is designed in the segmentation subnet to solve the problem of tumor over-segmentation. A dynamic weighted average multi-task loss is used to make the model achieve optimal performance in both tasks simultaneously. The experimental results of this method on 295 HCC patients are superior to other multi-task learning methods, with a Dice similarity coefficient (Dice) of (83.9 ± 0.88)% on the segmentation task, while the average recall is (86.08 ± 0.83)% and an F1 score is (80.05 ± 1.7)% on the classification task. The results show that the multi-task learning method proposed in this paper can perform the classification task and segmentation task well at the same time, which can provide theoretical reference for clinical diagnosis and treatment of HCC patients.
Humans ; Carcinoma, Hepatocellular ; Liver Neoplasms ; Learning

OBJECTIVE: To study the anatomical characteristics of blood vessels in the lateral segment of the vertebral body through the surgical approach of oblique lumbar interbody fusion (OLIF) using MRI imaging, and evaluate its potential vascular safety zone. METHODS: The lumbar MRI data of 107 patients with low back and leg pain who met the selection criteria between October 2019 and November 2022 were retrospectively analyzed. The vascular emanation angles, vascular travel angles, and the length of vessels in the lateral segments of the left vertebral body of L ₁-L ₅, as well as the distance between the segmental vessels in different Moro junctions of the vertebral body and their distances from the edges of the vertebrae in the same sequence (bottom marked as I, top as S) were measured. The gap between the large abdominal vessels and the lateral vessels of the vertebral body was set as the lateral vascular safe zones of the lumbar spine, and the extent of the safe zones (namely the area between the vessels) was measured. The anterior 1/3 of the lumbar intervertebral disc was taken as the simulated puncture center, and the area with a diameter of 22 mm around it as the simulated channel area. The proportion of vessels in the channel was further counted. In addition, the proportions of segmental vessels at L ₅ without a clear travel and with an emanation angel less than 90° were calculated. RESULTS: Except for the differences in the vascular emanation angles between L ₄ and L ₅, the vascular travel angles between L ₁, L ₂ and L ₄, L ₅, and the length of vessels in the lateral segments of the vertebral body among L ₁-L ₄ were not significant ( P>0.05), the differences in the vascular emanation angles, vascular travel angles, and the length of vessels between the rest segments were all significant ( P<0.05). There was no significant difference in the distance between vessels of L ₁, L ₂ and L ₂, L ₃ at Moro Ⅰ-Ⅳ junctions ( P>0.05), in L ₃, L ₄ and L ₄, L ₅ at Ⅱ and Ⅲ junction ( P>0.05). There was no significant difference in the vascular distance of L ₂, L ₃ between Ⅱ, Ⅲ junction and Ⅲ, Ⅳ junction, and the vascular distance of L ₃, L ₄ between Ⅰ, Ⅱ junction and Ⅲ, Ⅳ junction ( P>0.05). The vascular distance of the other adjacent vertebral bodies was significant different between different Moro junctions ( P<0.05). Except that there was no significant difference in the distance between L ₂I and L ₃S at Ⅰ, Ⅱ junction, L ₃I and L ₄S at Ⅱ, Ⅲ junction, and L ₂I and L ₃S at Ⅲ, Ⅳ junction ( P>0.05), there was significant difference of the vascular distance between the bottom of one segment and the top of the next in the other segments ( P<0.05). Comparison between junctions: Except for the L ₃S between Ⅰ, Ⅱ junction and Ⅱ, Ⅲ junction, and L ₅S between Ⅰ, Ⅱ junction and Ⅱ, Ⅲ and Ⅲ, Ⅳ junctions had no significant difference ( P>0.05), there were significant differences in the distance between the other segmental vessels and the vertebral edge of the same sequence in different Moro junctions ( P<0.05). The overall proportion of vessels in the simulated channels was 40.19% (43/107), and the proportion of vessels in L ₁ (41.12%, 44/107) and L ₅ (18.69%, 20/107) was higher than that in the other segments. The proportion of vessels in the channel of Moro zone Ⅰ (46.73%, 50/107) and zone Ⅱ (32.71%, 35/107) was higher than that in the zone Ⅲ, while no segmental vessels in L ₁ and L ₂ were found in the channel of zone Ⅲ ( χ ²=74.950, P<0.001). Moreover, 26.17% (28/107) of the segmental vessels of lateral L ₅ showed no movement, and 27.10% (29/107) vascular emanation angles of lateral L ₅ were less than 90°. CONCLUSION L ₁ and L ₅ segmental vessels are most likely to be injured in Moro zones Ⅰ and Ⅱ, and the placement of OLIF channels in L _{4, 5} at Ⅲ, Ⅳ junction should be avoided. It is usually safe to place fixation pins at the vertebral body edge on the cephalic side of the intervertebral space, but it is safer to place them on the caudal side in L _{1, 2} (Ⅰ, Ⅱ junction), L _{3, 4} (Ⅲ, Ⅳ junction), and L _{4, 5} (Ⅱ, Ⅲ, Ⅳ junctions).
Humans ; Retrospective Studies ; Spinal Puncture ; Magnetic Resonance Imaging ; Anticoagulants ; Bone Nails

Objective:To explore the effects of general anesthesia and combined spinal and epidural anesthesia on inflammatory factors and pain in patients with osteoarthritis after total knee arthroplasty.Methods:A total of 84 patients with osteoarthritis who underwent unilateral total knee arthroplasty in Hulunbuir People's Hospital from January 2020 to May 2021 were selected as the research subjects. They were randomly divided into general anesthesia group (40 cases) and combined spinal and epidural anesthesia group (44 cases). Venous blood samples of 5 ml were collected before operation and 6, 24, 48 hours after operation, and the contents of inflammatory factors [tumor necrosis factor-α (TNF-α), interleukin (IL)-1β, IL-6] in serum were determined by enzyme-linked immunosorbent assay (ELISA). The visual analogue pain scale (VAS) of the two groups at 30 min, 6, 24 and 48 hours after operation was compared.Results:At 6 and 24 hours after operation, TNF-α, IL-1β and IL-6 levels in the combined spinal and epidural anesthesia group were lower than those in the general anesthesia group ( t = 4.17, 3.85, 8.95, 10.98, 10.04, 9.87, P < 0.05). There were significant differences in the levels of TNF-α, IL-1β and IL-6 at different time points between the general anesthesia group and combined spinal and epidural anesthesia group ( F = 271.67, 149.26, 81.70, 189.36, 102.44, 157.32, P < 0.001). At 6 and 24 hours after operation, the VAS scores of patients in the combined spinal and epidural anesthesia group were significantly lower than those in the general anesthesia group ( t = 6.60, 3.66, P < 0.05). There were statistically significant differences in VSA scores between the two groups at different time points ( F = 67.47, 52.37, P < 0.05). Conclusion:The effect of combined spinal and epidural anesthesia is significantly higher than general anesthesia in inhibiting the expression of TNF-α, IL-1β and IL-6 in patients with osteoarthritis after operation, and the effect of analgesia is obvious.

Objective:To explore the feasibility and safty of robot assisted trans-diaphragmatic intropericardial inferior vena cava occlusion and thrombectomy in treatment of Ⅳa grade tumor thrombus without cardiopulmonary bypass and thoracotomy.Methods:The clinical data of 4 patients with renal cell carcinoma and Ⅳa grade tumor thrombus by robot assisted trans-diaphragmatic intropericardial inferior vena cava occlusion and thrombectomy from January 2013 to June 2019 were retrospectively analyzed. The median age was 53.5 (53-70) years. The average body mass index was 23.25 (20.7-26.3) kg/m 2. The tumors were located on the right side in 2 cases. The average maximum diameter of the tumor was 8.1 (3.6-11.2) cm.Preoperative tumor thrombus of all patients was classified as Ⅳa. The average preoperative length of tumor thrombus in vena cava was 12.3 (11.8-18.0) cm. All the operations were performed under multidisciplinary cooperation of urology, hepatobiliary, cardiovascular, ultrasound and anesthesiologist team. Surgical procedure: Robot assisted liver mobilization was used to expose the inferior vena cava. Under the guidance of intraoperative ultrasound, the central tendon and pericardium of diaphragm were dissected until the inferior vena cava and right atrium in the superior pericardium were exposed. The first porta hepatis and inferior vena cava were blocked in turn.The vena cava thrombectomy and inferior vena cava reconstruction were performed. Results:All the operations were completed without conversion. The median operation time was 553.5 (338-642) minutes, and the median time of the first porta hepatis occlusion was 18.1 (14-32)minutes. The median blood loss was 1 900(1 000-2 600)ml. All patients were transferred to ICU after operation. The median length of stay in ICU was 7(4-8) days, and the median time of indwelling drainage tube was 8(4-12) days. The average postoperative hospital stay was 13(11-20) days. There were 1 case of grade Ⅱ and 3 cases of grade Ⅲ complications (Clavien classification). One case had paroxysmal supraventricular tachycardia, one case had lymphatic fistula, one case had pleural effusion with atelectasis, and one case had hepatic and renal insufficiency and lymphatic fistula. The complications were improved after treatment. There was no perioperative death.Conclusions:Robot assisted trans-diaphragmatic intropericardial inferior vena cava occlusion and thrombectomy is an alternative method for the treatment of Ⅳa grade inferior vena cava tumor thrombus. Using this method, Ⅳa grade tumor thrombus can be treated without cardiopulmonary bypass and thoracotomy, with controllable complications and zero perioperative mortality.

Purpose: We aimed to investigate whether obtaining a higher level of education was causally associated with lower breast cancer risk and to identify the causal mechanism linking them. Methods: The main data analysis used publicly available summary-level data from 2 large genome-wide association study consortia. Mendelian randomization (MR) analysis used 65 genetic variants derived from the Social Science Genetic Association Consortium as instrumental variables for years of schooling. The outcomes from the Breast Cancer Association Consortium (BCAC) were the overall breast cancer risk (122,977 cases/105,974 controls in women) and the two subtypes: estrogen receptor (ER)-positive breast cancer and ER-negative breast cancer. Fixed and random effects inverse variance weighted methods were used to estimate the causal effects, along with other additional MR methods for sensitivity analyses. Results: Results showed that each additional standard deviation of 4.2 years of education was causally associated with a 27% lower risk of ER-negative breast cancer (odds ratio, 0.73; 95% confidence interval, 0.64–0.84; p-value < 0.001). This finding was consistent with the results of the sensitivity analyses. Physical activities can help improve the protective effect of education against breast cancer, with relatively large mediation proportions. Education increases the risk of ER-positive breast cancer due to alterations in high-density lipoprotein level, triglyceride level, height, waist-to-hip ratio, body mass index, and smoking status, with relative medium mediation proportions. Other mediators including low-density lipoprotein, hip circumference, number of cigarettes smoked per day, time spent performing light physical activity, and performing vigorous physical activity for > 10 minutes explain a small part of the causal effect of education on the risk of developing breast cancer, and their mediation proportion is approximately 1%. Conclusion A low level of education is a causal risk factor in the development of breast cancer as it is associated with poor lipid profile, obesity, smoking, and types of physical activity.

Objective:To clarify the anatomical characteristics and adjacent relationship of the superior segment of the inferior vena cava during laparoscopic surgery.Methods:In December 2018, two frozen and two fresh adult cadavers were dissected. The chest of the frozen cadavers was opened along the bilateral midline of the clavicle, the anterior pericardial wall was opened, and the superior vena cava and the inferior vena cava was dissected. The abdominal cavity was opened along the midline of the abdomen, the left and right hepatic lobes were turned over, the inferior vena cava and the second hilum of the posterior segment of the liver were exposed, and the hiatus of the inferior vena cava was opened and entered the pericardium.The anatomical characteristics and adjacent relationship of the superior segment of the inferior vena cava were observed, and the length of the superior segment of the inferior vena cava was measured. The fresh frozen cadaver patients underwent laparoscopic surgery.Five 12 mm trocars were placed at the side of umbilicus, right rectus abdominis about 4 cm from umbilicus, midline of abdomen about 6 cm above umbilicus, right axillary front about 2 cm below inferior edge of liver, left midline of clavicle about 2 cm below inferior edge of liver. Laparoscopic-assisted turning of the left and right hepatic lobes, exposing the posterior inferior vena cava and the second hilum of the liver, opening of the vena cava hiatus into the pericardium.The anatomical characteristics and adjacent relationship of the upper diaphragmatic segment of the inferior vena cava were observed.Results:In two autopsies, the inferior vena cava entered the chest through the cava sulcus of the liver and the phrenic foramen cava, and then through the fibrous pericardium into the right atrium. The length from the diaphragm of inferior vena cava to the right atrium was 1.67 cm, 2.57 cm. In laparoscopic operation, the diaphragm entrance of the posterior segment of the liver inferior vena cava, the second hepatic portal and the inferior vena cava could be well exposed.The diaphragm could be opened along the hole of the vena cava with a relatively non vascular anatomical layer of adipose tissue.There was a large anatomical gap between the pericardium and the right atrium, and the inferior vena cava, the superior vena cava and the right atrium could be well exposed, and the whole diaphragm could be completely and continuously exposed from the bottom to the inferior vena cava at the entrance segment of the right atrium.Conclusions:There was a relatively avascular anatomical layer beside the inferior vena cava. During laparoscopic operation, opening the diaphragm through the abdominal cavity could safely enter the pericardium and expose the inferior vena cava, the superior vena cava and the right atrium, which provides a possibility for the removal of Mayo Ⅳ grade inferior vena cava tumor thrombus through this approach.