Objective: To characterize perioperative dynamic changes in immune-cell phenotypes and inflammatory cytokines in patients undergoing CPB (cardiopulmonary bypass) cardiac surgery, and to explore their associations with postoperative outcomes. Methods: In this prospective cohort study, 120 adult patients who underwent elective cardiac surgery under CPB at West China Hospital from May 2022 to March 2023 were enrolled. Perioperative immune-cell phenotypes and concentrations of 40 inflammation-related cytokines were measured. The primary outcomes were the sequential organ failure assessment (SOFA) score at 24 h after surgery and ΔSOFA (the peak SOFA score within 48 h after surgery minus the preoperative SOFA score). Secondary outcomes included major adverse cardiovascular events (MACE), acute kidney injury (AKI), respiratory failure, severe liver injury, and infection. Results: The mean age of enrolled patients was 57±10 years. Of these, 52% (62/120) were male and 90% (108/120) underwent valve surgery. During the rewarming to the end of CPB, neutrophil counts rapidly increased (7.39×10 /L vs preoperative 3.07×10 /L, P<0.001), with significant upregulation of CD11b (7.30×10 /L vs preoperative 3.05×10 /L, P<0.001) and CD54 (7.15×10 /L vs preoperative 2.99×10 /L, P<0.001). Lymphocyte counts increased at the end of CPB (1.75×10 /L vs preoperative 1.12×10 /L, P<0.001) but decreased significantly at 24 h after surgery (0.59×10 /L vs preoperative 1.12×10 /L, P<0.001). Plasma analysis showed that multiple pro-inflammatory cytokines increased during CPB and remained elevated up to 24 h after surgery; five chemokines and the anti-inflammatory cytokine IL-10 peaked at the end of CPB. The SOFA score increased from 1 (1, 2) preoperatively to 7 (5, 10) at 24 h after surgery, with a ΔSOFA of 6 (4, 8). Within 30 days after surgery, 48 patients (40.0%) developed AKI, 17 (14.2%) developed infection, 4 (3.3%) developed severe liver injury, 3 (2.5%) developed respiratory failure, and 3 (2.5%) experienced MACE. During the 2-year follow-up, 8 patients (6.7%) experienced MACE and 5 (4.2%) died. Conclusion: Multi-organ dysfunction is common after cardiac surgery under CPB (median ΔSOFA, 6), accompanied by perioperative activation of multiple immune-cell subsets and upregulation of pro-inflammatory, anti-inflammatory, and chemotactic mediators. This study provides data-driven evidence and research clues for further investigation of the associations between CPB-related immune perturbations and postoperative organ dysfunction and clinical outcomes.

Objective To determine the knee joint cartilage thickness using different methods and explore the feasibility of mathematical statistical models of dataset for the prediction of cartilage thickness.Methods A total of 304 patients diagnosed as knee osteoarthritis(OA)combined with varus deformity and undergoing unilateral total knee arthroplasty at the Second Affiliated Hospital of Army Medical University from March 2023 to March 2024 were selected for the study.All patients had complete preoperative and postoperative clinical data.The healthy cartilage at four anatomical sites of patients,including the distal femur lateral condyle,lateral tibial plateau,posterior medial femoral condyle,and posterior lateral femoral condyle were selected,and the knee joint cartilage thickness was determined based on preoperative MRI analysis,robotic navigation system tracing,tissue section of surgical specimen and digital vernier caliper.The baseline indicators of demographics,disease and imaging ffor patients were collected to construct a dataset,and four models of linear regression analysis,principal component analysis,Least Absolute Shrinkage and Selection Operator(LASSO)regression analysis,and K-nearest neighbors(KNN)analysis were established for predicting the accuracy,determination coefficient(R2)and root mean square error(RMSE),and the regression equation for predicting cartilage thickness was established.Results The knee joint cartilage thicknesses determined by preoperative MRI analysis,robotic navigation system tracing,tissue section of surgical specimen had no statistically significant difference with that by digital vernier caliper(P>0.05).The predictive efficiencies of models of linear regression analysis,principal component analysis,and LASSO regression analysis for the knee joint cartilage thickness all failed to meet the expectations(R2<0.3,RMSE>0.03).The predictive effect of KNN model on the cartilage thickness of the distal femur lateral condyle and lateral tibial plateau was not ideal(R2=0.23,RMSE=0.29),while it had potential predictive value(accuracy=0.21,accuracy=0.15).Conclusion The prediction model of knee joint cartilage thickness based on individual parameters has certain scientificity,and the feasibility of KNN model is relatively high.However,due to insufficient sample size and unclear individual parameter weight,the efficiencies of the four established prediction models are not ideal,which fails to provide definite prediction equations.Therefore,the construction scheme of the prediction model still needs to be further optimized.

Objective:To explore the dosimetric characteristics of intensity modulated proton therapy (IMPT), intensity modulated radiation therapy (IMRT) and tomotherapy (TOMO) techniques applied in the irradiation of pediatric whole central nervous system tumors.Methods:Taking the target area of a 14-year-old pediatric patient clinically diagnosed with atypical teratoid/rhabdomyoid tumor, meningeal metastasis by Shandong Cancer Hospital and Institute, and undergoing craniospinal irradiation (CSI) as an example, IMPT, IMRT and TOMO plans were designed respectively based on the clinical prescription of the target area and the limit requirements of organs at risk (OARs). The conformal index (CI), homogeneity index (HI) and gradient index (GI) of each planning target volume, as well as the dose volume index of normal tissues, were evaluated to compare the dosimetric characteristics of the three types of plans.Results:The CI (0.71), HI (0.05) and GI (3.13) of the IMPT plan were comparable to those of IMRT plan (0.80, 0.08, 3.14). The HI (0.03) and GI (2.54) of the TOMO plan were excellent, which were all within the clinically acceptable range. The irradiation dose to parallel organs in the IMPT plan was lower than that in the IMRT and TOMO plan. In the IMPT plan, V 5 of lungs was 2.9%, IMRT plan was 37.6%, and TOMO plan was 43.5%. The D mean of liver in the IMPT plan was 0.01 Gy (RBE), IMRT plan was 6.12 Gy, and TOMO plan was 6.39 Gy. In the IMPT plan, none of the bladder, rectum, and femoral head received the dose, while there was low-dose radiation in both IMRT and TOMO plan. For serial organs adjacent to and within the target area, the D max of spinal cord and brainstem in IMPT plan was 39.89 and 39.88 Gy (RBE), respectively; in IMRT plan, they were 39.43 and 38.59 Gy, respectively; and in TOMO plan, they were 38.41 and 37.69 Gy, respectively. The low-dose area in the IMPT plan was significantly better than the photon radiotherapy plans. Among them, the absolute volume IMPT plan occupied by 10% of the prescribed dose area in the patient's body was reduced by 70.10% compared with IMRT plan and 76.96% compared with TOMO plan; the 30% prescribed dose volume IMPT plan was reduced by 53.49% compared with IMRT plan and 62.51% compared with TOMO plan; the 50% prescribed dose volume IMPT plan was reduced by 39.06% compared with IMRT plan and 42.23% compared with TOMO plan. Conclusions:The IMPT plan demonstrated significantly reduced low-dose exposure and lower doses to parallel OARs compared to both IMRT and TOMO plans in pediatric CSI. The CI, HI and GI of the three plans can all meet the clinical requirements. However, for serial organs adjacent to and within the target area, the D max of the IMPT plan may be higher than that of IMRT and TOMO plans.

Objective:To investigate the dosimetric characteristics of intensity modulated proton therapy (IMPT) and photon volumetric modulated arc therapy (VMAT) in typical head and neck malignant tumors.Methods:Three types of typical head and neck tumors (nasopharyngeal carcinoma, parotid gland carcinoma, laryngeal carcinoma) treated at Shandong Cancer Hospital and Institute from December 2023 to December 2024 were taken as research subjects. IMPT and VMAT radiotherapy plans were created according to clinical prescription requirements of target and organs at risk limits respectively. The conformity index (CI), homogeneity index (HI) and gradient index (GI) for target coverage of two radiotherapy plans were evaluated for 3 patients, as well as the dosimetric indicators of organs at risk.Results:The CI of IMPT for nasopharyngeal carcinoma, parotid gland carcinoma and laryngeal carcinoma were 0.70, 0.72 and 0.67, respectively. The HI were 0.11, 0.08 and 0.08, respectively. The GI were 3.08, 2.49 and 3.75, respectively. The CI of VMAT plans were 0.77, 0.82 and 0.91, respectively. The HI were 0.12, 0.10 and 0.04, respectively. The GI were 3.67, 2.63 and 3.45, respectively. The results showed that CI of IMPT plan was slightly lower than that of VMAT plan, and HI of IMPT plan was comparable to that of VMAT plan, the GI of the IMPT plan for patients with nasopharyngeal carcinoma and parotid gland carcinoma was lower than that of the VMAT plan, and the GI of the IMPT plan for patient with laryngeal carcinoma was higher than that of the VMAT plan, and all were within the clinically acceptable range. The IMPT plan has demonstrated significant dose advantages in the treatment of nasopharyngeal carcinoma, parotid gland carcinoma and laryngeal carcinoma. For patient with nasopharyngeal carcinoma, the IMPT plan reduced the D max of the left and right crystals by 54.1% and 50.4%, respectively, compared to VMAT plan, and reduced the D mean of the oral and laryngeal tissues by 40.5% and 49.6%, respectively. For patient with parotid gland carcinoma, IMPT plan reduced the D max of the brainstem and spinal cord by 66.2% and 40.5%, respectively, compared to VMAT plan. For patient with laryngeal carcinoma, IMPT reduced spinal cord D max by 77.0%, while thyroid cartilage D mean increased by 8.0% compared to VMAT plan. For the additional dose in the patients' body, taking the absolute volumes occupied by the prescribed dose areas of 10%, 30%, and 50% in the patients' body as examples, IMPT plan of nasopharyngeal carcinoma patient decreased by 29.7%, 29.6%, and 34.9% compared to VMAT plan, respectively. IMPT plan of parotid gland carcinoma patient decreased by 61.0%, 39.7%, and 17.4% compared to VMAT plan, respectively. IMPT plan of laryngeal carcinoma patient decreased by 63.9%, 31.7%, and 4.1% compared to VMAT plan, respectively. Conclusions:Compared with VMAT plan, IMPT plan can effectively reduce the irradiation dose of most organs at risk near the target of head and neck tumors, but the dose of string organs close to the target area may be higher, which needs attention.

Objective:To evaluate the radiological and functional outcomes of moderate to severe hallux valgus patients with enlarged distal metatarsal articular angle (DMAA) underwent modified Chevron osteotomy.Methods:The clinical data of patients with moderate and severe hallux valgus with increased distal metatarsal joint angle who accepted surgery operation in the Department of Foot and Ankle Surgery of Yantaishan Hospital from October 2020 to December 2022 were retrospectively analyzed. All patients underwent modified Chevron osteotomy. Taking the proximal end of the metatarsal head centre as the osteotomy apex, the vertical arm osteotomy line in the sagittal plane made an angle of ≤80° with the metatarsal stem, the horizontal plane was inclined to the lateral distal end of the metatarsal head by about 10°, and the sagittal plane metatarsal arm osteotomy line made an angle of ≥90° with the vertical arm osteotomy line; at the proximal osteotomy surface, another cuneiform bone with its base on the medial and its apex on the lateral was resected. The deformity correction was insufficient and Akin osteotomy was performed in combination. Weil osteotomy was performed in combination with metatarsalgia. Radiological assessment including the hallux valgus angle (HVA), intermetatarsal angle (IMA), DMAA, the joint congruity angle (JCA), forefoot bone width and soft tissue width was performed preoperatively and at last follow-up postoperatively. American Orthopedic Foot and Ankle Society/hallux metatarsophalangeal-interphalangeal scale (AOFAS/HMIS) was used for clinical and functional evaluation, total score from 0 to 100, with higher scores indicating better function.Visual analogue scale (VAS) was used for pain valuation, total score from 0 to 10, with higher scores indicating more pain. A questionnaire survey on patient satisfaction was conducted at the last follow-up. Shapiro-Wilk test was used for normal distribution test, and measurement data following normal distribution were represented as Mean±SD. Paired t-test was used for comparison before and after operation. Other indicators conformed to non-normal distribution were denoted by M( Q1, Q3) and were tested by Wilcoxon signed-rank test. P<0.05 was considered statistically significant. Results:Fifty-two feet of 48 patients (5 males, 43 females; mean age (52.4±14.9) years; range, 24 to 78 years) were enrolled. Before the operation, 8 feet combined with metatarsalgia, among them, 7 feet underwent modified Chevron+ Akin+ Weil osteotomy, and 1 foot underwent modified Chevron+ Weil osteotomy. Among the 44 feet without metatarsalgia, 11 feet underwent modified Chevron osteotomy and 33 feet underwent modified Chevron+ Akin osteotomy. The mean follow-up time was 17.8 months (12-24 months). The HVA angle decreased from 38.30°±7.59° before surgery to 10.00°±5.73° at the last follow-up; the IMA angle decreased from 16.08°(12.89°, 18.24°) to 4.81°(3.62°, 7.57°); the DMAA angle decreased from 18.35°(13.03°, 27.47°) to 4.52°(2.68°, 7.09°); JCA decreased significantly from 15.93°(10.25°, 23.06°) to 3.56°(1.71°, 6.98°); forefoot bone width decreased from (90.05±6.12) mm to (82.75±5.01) mm; forefoot soft tissue width decrease from 102.25(96.77, 107.15) mm to 98.08(91.01, 100.60) mm; the VAS decreased from 6(5.5, 7) points to 0(0, 0) points; the score according to the AOFAS/HMIS forefoot was increased from 49(42, 52.5) points to 90(83.5, 95) points; which were statistically significant compared with that before the operation (all P<0.01). There was no statistically significant difference in the first metatarsal length before the operation and at the last follow-up [54.60(52.86, 56.42) mm vs. 54.29(51.85, 56.35) mm, P>0.05]. In the post-operative period, there were 8 feet had limited metatarsophalangeal joint movement, 3 feet had limited interphalangeal joint movement, 5 feet had limited movement in both joints, which did not affect walking and function; 3 feet of partial recurrence of hallux valgus, 2 feet of screw irritation pain, 1 foot of cystic degeneration of the first metatarsal head, and no complications such as metastatic metatarsalgia. The satisfaction survey showed that the satisfaction rate of patients with the orthopedic effect was 90.4% (47/52). Conclusion:The modified Chevron osteotomy is effective in the treatment of moderate to severe hallux valgus with enlarged DMAA. Careful intraoperative operation and standardized postoperative rehabilitation training can reduce complications.

AIM:This study aimed to investigate the effect of ischemic post-conditioning(I-post-C)on lung ischemia-reperfusion injury(LIRI)in rats and relationship between I-post-C and zinc homeostasis.METHODS:SPF SD rats(6～8 weeks old)were randomly divided into four groups,with eight rats in each group:control group,ischemia/reper-fusion(I/R)group,I-post-C group and I-post-C+zinc ion chelator TPEN group.Inductively coupled plasma mass spec-trometry(ICP-MS)was used to measure the concentration of zinc ions in lung tissues.HE staining,lung wet/dry weight ra-tio(W/D),total lung water content(TLW),and index of quantitative assessment(IQA)of lung injury were used to detect the degree of lung tissue injury in each group.Mitochondrial membrane potential was measured using extraction and JC-1 mitochondrial membrane potential detection kits.TUNEL assay was used to detect the level of apoptosis in lung tissues.Western blot was used to detect the protein expression levels of caspase-3,solute carrier family 39 member 8(SLC39A8/ZIP8),solute carrier family 30 member 9(SLC30A9/ZNT9),and PI3K/AKT/GSK-3β in lung tissues of each group.RT-qPCR was used to detect ZIP8 and ZNT9.RESULTS:Compared to the control group,the I/R group showed significantly aggravated lung tissue injury(P<0.01),decreased zinc ion levels(P<0.01),enhanced cell apoptosis(P<0.05),re-duced mitochondrial membrane potential(P<0.01),decreased PI3K/AKT/GSK-3β phosphorylation levels(P<0.05,P<0.01),increased cleaved caspase-3/pro-caspase-3 ratio(P<0.01),and reduced ZIP8 expression(P<0.05).Compared to the I/R group,the I-post-C group exhibited alleviated injury(P<0.05 or P<0.01),increased zinc ion levels(P<0.01),reduced apoptosis(P<0.01),restored mitochondrial membrane potential(P<0.01),elevated PI3K/AKT/GSK-3β phosphorylation levels(P<0.05,P<0.01),decreased cleaved caspase-3/pro-caspase-3 ratio(P<0.05),and in-creased ZIP8 expression(P<0.05).Compared to the I-post-C group,the I-post-C+TPEN group demonstrated aggravated injury(P<0.01),decreased zinc ion levels(P<0.01),enhanced apoptosis(P<0.01),reduced mitochondrial membrane potential(P<0.05),decreased PI3K/AKT/GSK-3β phosphorylation levels(P<0.05,P<0.01),increased cleaved cas-pase-3/pro-caspase-3 ratio(P<0.05),and reduced ZIP8 expression(P<0.05).ZNT9 expression showed no significant differences among the groups(P>0.05).CONCLUSION:Ischemic postconditioning can improve LIRI by regulating zinc homeostasis,activating PI3K/AKT signaling pathway,inactivating glycogen synthase kinase 3β,inhibiting the de-cline of mitochondrial membrane potential,and antagonizing cell apoptosis in rats.

Objective:To investigate the differences in prosthesis implantation accuracy, biomechanical indicators, and 2-year postoperative clinical outcomes between robotic-assisted traditional posterior approach (RA-PLA) and robotic-assisted direct anterior approach (RA-DAA) in total hip arthroplasty (THA).Methods:This study is a prospective randomized controlled trial. Patients with unilateral femoral head ischemic necrosis or primary hip osteoarthritis who meet the inclusion and exclusion criteria and were admitted to the Department of Orthopedics,Xinqiao Hospital, Army Medical University from May to September 2022. Divided into RA-PLA group and RA-DAA group through central randomization. Use cumulative and fitting methods to analyze the learning curve of robotic surgery and eliminate cases before the inflection point of the learning curve. Compare the abduction angle and anteversion angle of acetabular cup implantation between two groups of patients, as well as the rate of falling into the safe zone, the difference in length between the two lower limbs, hip joint eccentricity, rotation center height, the complete accuracy of prosthesis planning (the number of cases in which acetabular cup prosthesis, femoral stem prosthesis specifications, and neck shaft angle were completely consistent with surgical planning during surgery/total cases×100%), patient reported outcome indicators (including Harris hip score (HHS), Western Ontario and McMaster Universities Osteoarthritis Index(WOMAC), and 12 item Short Form Health Survey (SF-12) score) and clinical outcomes. Data comparison was conducted using independent sample t-test, Wilcoxon rank sum test, chi square test, Fisher′s exact probability method, or repeated measures analysis of variance. Results:A total of 98 patients were included in this study, with 48 in the RA-PLA group and 50 in the RA-DAA group. After excluding cases before the inflection point of the learning curve, 30 patients were included in each group. There was no statistically significant difference in baseline data between the two groups before surgery (all P>0.05). There was no significant difference in the values of the anterior tilt angle and abduction angle between the two groups of acetabular cups compared to preoperative planning (all P>0.05). The proportion of patients who fell into the Lewinnek and Callanan safe zones was 90.0% (27/30) and 96.7% (29/30), respectively ( χ2=0.268, P=0.605). There was no significant difference in postoperative lower limb length, hip joint eccentricity, and rotation center height deviation and grading between the two groups (all P>0.05). The complete accuracy of prosthesis planning in the RA-DAA group was higher than that in the RA-PLA group (86.7% (26/30) compared to 63.3% (19/30), χ2=4.356, P=0.037).All patients were followed up for more than 2 years. In terms of postoperative HHS, WOMAC, and SF-12 score, there was no statistically significant difference in the inter group effect comparison (all P>0.05), but there was a significant statistical significance in the time effect (all P<0.05). There was no significant difference in the incidence of perioperative complications and adverse events between the RA-DAA group and the RA-PLA group (20.0% (6/30) vs. 13.3% (4/30), χ2=0.480, P=0.488). Conclusions:RA-DAA and RA-PLA techniques can achieve similar clinical efficacy after two years of surgery, and both can achieve similar reconstruction accuracy in terms of acetabular cup implantation angle, lower limb length, hip joint eccentricity, and rotation center height. The accuracy of prosthesis planning in RA-DAA is higher.

AIM:This study aimed to confirm the glycolytic inhibitory activity of 3-bromopyruvic acid(3BP)and to assess whether this inhibition could ameliorate hypoxia-induced pulmonary hypertension in rats.METHODS:PAH model rats were generated from normal SD rats via exposure to normal pressure and hypoxia.Intervention groups I and II(6 rats per group)were then intraperitoneally injected with 3BP(15 mg/kg),and the normal and hypoxia groups(6 rats per group)were given the same amount of normal saline for a total of 21 d.The average pulmonary artery pressure of the rats in each group was measured via right heart catheterisation,and hilar tissue measurements.The right ventricle(RV),left ventricle,and interventricular septum(LV+S)were weighed,and the ratio of RV/(LV+S)was calculated as an index of right ventricular hypertrophy.Right lower lung tissues were fixed in 4%paraformaldehyde-PBS buffer,sec-tioned in conventional paraffin(5 μm thick),stained with HE and Masson,photographed under a microscope.Then the thickness ratio of the tunica media and the area ratio of collagen fibres were calculated.The expression of pyruvate kinase isozyme type M2(PKM2),nucleotide-binding oligomerization domain-like receptor protein 3(NLRP3),and pyruvate de-hydrogenase(PDH)proteins in the hilar tissues of each group were detected by western blot,whereas interleukin-1β(IL-1β)and IL-18 contents were detected using ELISA,and lactic acid content was detected using a lactic acid kit.RE-SULTS:The results showed that 3-brpa effectively inhibited glycolysis and significantly improved hypoxia-induced pulmo-nary hypertension in rats.Compared with the hypoxia group,in intervention group II,PKM2 expression was decreased(P<0.05),PDH expression increased significantly(P<0.01),and NLRP3 expression was decreased(P<0.05).The IL-18 and IL-1β contents decreased(P<0.05 or P<0.01,respectively).Pulmonary hemodynamic indexes showed that the pro-portion of the right ventricle and the mean pressure of the pulmonary artery decreased(P<0.05 or P<0.01,respectively).The HE and Masson staining results showed that the thickness ratio of the tunica media and the area ratio of collagen fibres decreased significantly(P<0.01).Lactic acid content was significantly decreased(P<0.01).CONCLUSION:This study showed that 3BP can inhibit glycolysis and alleviate hypoxia-induced pulmonary hypertension in rats.

Background:To compare the efficacy and safety of monthly administrations of gonadotropin releasing hormone (GnRH) agonists LY01005 and Zoladex ? in Chinese patients with premenopausal breast cancer. Methods:From October 2020 to November 2021, 188 premenopausal breast cancer patients were enrolled in 34 hospitals and randomized 1:1 to receive either LY01005 or Zoladex ? every 28 days for a total of three injections. All patients concomitantly received oral tamoxifen (TAM). The primary efficacy endpoint was cumulative probability of maintaining menopausal level [oestradiol (E2) ≤30 pg/ml] from day 29 to day 85. The second efficacy endpoint included changes in E2, luteinizing hormone (LH), and follicle-stimulating hormone (FSH) compared with the baseline. Pharmacokinetics (PK), pharmacodynamics (PD), and safety were analyzed. The study also evaluated the pharmacokinetic and pharmacodynamic characteristics of LY01005. Results:A total of 188 patients were randomised and 187 patients received either LY01005 or Zoladex ?. Cumulative probabilities of maintaining menopausal level (E2≤30 pg/ml) from day 29 to day 85 were 93.1% for LY01005 and 86.3% for Zoladex ?. The between-group difference was 6.8% (95% CI: -2.3%, 15.9%) and primary efficacy in the LY01005 group was not inferior to that in the Zoladex ? group. Changes in E2, LH, and FSH levels compared with the baseline were equivalent between the two groups (E2: 89.34% to 90.23% vs. 82.11% to 85.02%; LH: 88.89% to 95.52% vs. 89.70% to 97.02%; FSH: 75.36% to 80.85% vs.73.07% to 80.24%, respectively). After three consecutive doses of LY01005, the LH and FSH levels of the subjects showed a transient increase after the first dose, reached a peak on the second day and then started to decrease. The LH and FSH reached a lower level and remained at or below that level until the 85th day. Both treatments were well-tolerated. Conclusion:LY01005 is as effective as Zoladex ? in suppressing E2 to menopausal levels in Chinese patients with premenopausal breast cancer, with a similar safety profile.

Objective:To investigate the clinical features and multi-slice spiral computed tomography(CT)imaging features of acute appendicitis in soldiers who have been living in plateau for a long time.Methods:The clinical features and imaging data of 56 cases of acute appendicitis in soldiers who have been living in plateau for a long time confirmed by surgery from February 2022 to August 2024 were retrospectively analyzed.Results:In 56 cases with acute appendicitis in soldiers who have been living in plateau for a long time,the appendectomy position results showed:anterior ileum 4 cases(7.14％),lower ileum 10 cases(17.86％),posterior cecum 16 cases(28.57％),lower cecum 9 cases(16.07％),lateral cecum 2 cases(3.58％),posterior ileum 6 cases(10.71％),high(subhepatic)9 cases(16.07％),and left lower abdominal 0 cases,retroperitoneal appendicitis 0 cases,which was suggested that the anatomical position variation of appendicitis in soldiers with acute appendicitis who have been living at high altitude for a long time was relatively large.The direct manifestations of multi-slice spiral CT showed:appendectomy enlarged diameter＞6 mm in 49 cases(87.50％),appendicular wall thickening＞2 mm in 42 cases(75.00％),ppendiceal dilation lumen and effusion in 29 cases(51.79％),appendix indistinctness in 3 cases(5.36％),lppendix fecalith:27 cases(48.21％),gas in the appendix in 16 cases(28.57％).Indirect findings of multi-slice spiral CT showed that,periappendiceal exudation with shadow in 32 cases(57.14％),appendiceal cellulitis with peripheral abscess in 9 cases(16.07％),peritonitis and ascites in 13 cases(23.21％),ileocecal intestinal wall thickening in 22 cases(39.29％),mesenteric lymph node enlargement in 16 cases(28.57％),reflexive intestinal stasis in ileocecal region was observed in 19 cases(33.93％).Conclusion:In the officers and soldiers with acute appendicitis who lived at high altitude for a long time,multi-slice spiral CT showed the direct manifestations of appendiceal thickening,tube wall thickening,lumen dilatation,fluid accumulation,etc.,and the indirect manifestations were periappendiceal exudation with shadow,appendiceal cellulitis with peripheral abscess,ileocecal intestinal wall thickening,reflexes of small intestine and mesenteric lymph node enlargement.Multi-slice spiral CT has the advantages of clear and intuitive,high safety,high resolution and simple operation in the diagnosis of acute appendicitis.