Background:Acute pancreatitis(AP)is a common disease of the digestive system,among which severe acute pancreatitis(SAP)has a high mortality rate.Finding more accurate and convenient methods for early recognition of SAP is one of the major challenges in clinical treatment.Aims:To explore the application value of the controlled attenuation parameter(CAP)of ultrasound elastography in predicting SAP.Methods:A retrospective cohort study was conducted involving 135 AP patients admitted to Jiading Branch of Shanghai General Hospital from February to October 2024.Patients were categorized into non-SAP and SAP groups according to the severity of the disease.Clinical data,local complications,laboratory indicators,and CAP were compared between the two groups.Univariate and multivariate Logistic regression analyses were used to identify independent risk factors for SAP.A SAP prediction model based on CAP was constructed according to the identified risk factors and the minimum Akaike information criterion(AIC).ROC curve and Bootstrap method were used to evaluate the efficacy of the prediction model and conduct internal validation,respectively.Results:There were statistically significant differences between the non-SAP group and SAP group in body mass index(BMI),incidence of hyperlipidemia,etiological composition,incidence of pleural and ascitic fluid,length of hospital stay,incidence of peripancreatic effusion,incidence of pancreatic necrosis,white blood cell count(WBC),D-dimer(D-D)level,blood glucose,triglyceride(TG),C-reactive protein(CRP),neutrophil count,procalcitonin(PCT),interleukin-6(IL-6),free triiodothyronine(FT3),and CAP(all P<0.05).Multivariate Logistic regression analysis showed that pancreatic necrosis(OR=13.39,95%CI:3.10-57.94,P<0.001)and CAP(OR=1.01,95%CI:1.01-1.02,P=0.038)were independent risk factors for SAP.The SAP prediction model based on CAP was formulated as:Logit(P)=-5.884+0.010×CAP+2.839×pancreatic necrosis+0.169×D-D+0.132×blood glucose+0.006×CRP.The model showed an area under the curve(AUC)of 0.834 for predicting SAP,which was superior to CAP alone(P<0.05).Internal validation indicated that the prediction model had high stability and accuracy(C-index=0.808).Conclusions:The prediction model constructed based on CAP has good clinical value for predicting SAP,providing a new perspective and tool for early identification and prognostic assessment of AP.

Background:Acute pancreatitis(AP)is a common disease of the digestive system,among which severe acute pancreatitis(SAP)has a high mortality rate.Finding more accurate and convenient methods for early recognition of SAP is one of the major challenges in clinical treatment.Aims:To explore the application value of the controlled attenuation parameter(CAP)of ultrasound elastography in predicting SAP.Methods:A retrospective cohort study was conducted involving 135 AP patients admitted to Jiading Branch of Shanghai General Hospital from February to October 2024.Patients were categorized into non-SAP and SAP groups according to the severity of the disease.Clinical data,local complications,laboratory indicators,and CAP were compared between the two groups.Univariate and multivariate Logistic regression analyses were used to identify independent risk factors for SAP.A SAP prediction model based on CAP was constructed according to the identified risk factors and the minimum Akaike information criterion(AIC).ROC curve and Bootstrap method were used to evaluate the efficacy of the prediction model and conduct internal validation,respectively.Results:There were statistically significant differences between the non-SAP group and SAP group in body mass index(BMI),incidence of hyperlipidemia,etiological composition,incidence of pleural and ascitic fluid,length of hospital stay,incidence of peripancreatic effusion,incidence of pancreatic necrosis,white blood cell count(WBC),D-dimer(D-D)level,blood glucose,triglyceride(TG),C-reactive protein(CRP),neutrophil count,procalcitonin(PCT),interleukin-6(IL-6),free triiodothyronine(FT3),and CAP(all P<0.05).Multivariate Logistic regression analysis showed that pancreatic necrosis(OR=13.39,95%CI:3.10-57.94,P<0.001)and CAP(OR=1.01,95%CI:1.01-1.02,P=0.038)were independent risk factors for SAP.The SAP prediction model based on CAP was formulated as:Logit(P)=-5.884+0.010×CAP+2.839×pancreatic necrosis+0.169×D-D+0.132×blood glucose+0.006×CRP.The model showed an area under the curve(AUC)of 0.834 for predicting SAP,which was superior to CAP alone(P<0.05).Internal validation indicated that the prediction model had high stability and accuracy(C-index=0.808).Conclusions:The prediction model constructed based on CAP has good clinical value for predicting SAP,providing a new perspective and tool for early identification and prognostic assessment of AP.

Preterm birth (PTB), predominantly induced by intraamniotic inflammation, stands as the foremost contributor to neonatal morbidity and mortality globally. Fetal inflammatory response syndrome, stemming from the activation of the innate immune system, signifies the occurrence of funisitis or chorionic vasculitis. Maternal-fetal complications associated with infection-related PTB encompass maternal sepsis, fetal demise, neonatal sepsis, neonatal neurological impairment, and chronic lung disease. The inflammatory cascade is initiated when Toll-like receptors present on immune cells within the fetal membranes and the female reproductive tract encounter pathogen-associated molecular patterns derived from infectious agents. Subsequently, the nuclear factor kappa-light-chain-enhancer of activated B cells facilitates the transcription of cytokines. The accumulation of neutrophils compromises the tissue integrity of the fetal membranes, leading to membrane rupture via the secretion of matrix metalloproteinases. Elevated prostaglandin levels prompt uterine contractions and cervical remodeling, resulting in progressive cervical effacement and dilation, ultimately culminating in fetal delivery. The diagnosis of PTB should encompass three pivotal criteria: gestational age, uterine activity, and the consequences of that uterine activity. The diagnosis of chorioamnionitis is established through a combination of clinical manifestations, laboratory findings, identification of infectious microorganisms, and placental pathology. Fetal monitoring involves antenatal ultrasonography and non-stress testing. The management of infection-related PTB involves controlling and treating the infection, timing delivery to coincide with optimal fetal lung maturity, and optimizing outcomes for both the mother and neonate. Current preventive strategies for PTB primarily focus on inhibiting myometrial contractions that arise from the inflammatory cascade initiating PTB. An understanding of these pathways serves as the cornerstone for the development of therapeutic interventions aimed at preventing PTB.

Objective:To explore the effects and possible mechanism of intestinal microbiota on lung injury in mice with acute necrotizing pancreatitis (ANP).Methods:The experimental mice were randomly assigned to normal control group (CON group), ANP model group (ANP group) and intestinal germ-free group (ABX group), with 6 mice in each group. The ANP mouse model was constructed by intraperitoneal injection of caerulein (100 μg/kg, for 10 times) at an interval of 1 hour each time, followed by 10 mg/kg lipopolysaccharide injection. Mice in ABX group were treated by Abx solution (0.5 g/L vancomycin, 1 g/L neomycin, 1 g/L metronidazole, and 1 g/L ampicillin), 1 ml/100 g gavage for 28 days before preparation of the ANP model. The CON group was injected intraperitoneally with an equal volume of PBS. Histopathologic examination of the pancreas, lungs, and terminal ileum was routinely performed. Serum amylase levels were measured using enzymatic kinetic chemistry, and serum diamine oxidase (DAO) and lung tissue myeloperoxidase (MPO) activities were measured using ELISA assay. Expression of inflammatory factors, pyroptosis-related molecules in lung tissue and intestinal epithelial tight junction proteins was detected by fluorescence quantitative PCR. Western blotting was used to detect the expression of the pyroptosis molecules caspase-1 and GSDMD in lung tissue, and intestinal epithelial tight junction proteins. Changes of bacterial distribution in lung tissue were measured by fluorescence in situ hybridization. Results:The pathological scores of pancreatic tissue of CON, ANP, and ABX group were (0.67±0.26), (7.33±0.82), and (5.67±0.81); the pathological scores of lung tissue were (1.67±0.41), (5.67±0.41), and (3.58±0.58); the pathological scores of ileal tissue were (0.58±0.52), (3.83±0.75), and (4.33±0.82); the serum amylase levels were (403.95±93.11), (1037.24±126.77), and (647.32±145.90)U/L; the MPO levels in lung tissue were (0.23±0.03), (0.63±0.09), and (0.48±0.05)U/g. ABX group had significantly lower scores in pancreatic and lung tissues, serum amylase levels, and MPO levels in lung tissue compared to ANP group, and all the differences were statistically significant (all P value <0.05). The expression level in pancreatis tissue from CON, ANP and ABX group of IL-1β mRNA was 1.84±0.90, 36.26±5.56 and 16.65±6.43, IL-6 mRNA was 1.07±0.15, 2.90±0.42 and 1.34±0.62, TNF-α mRNA was 0.47±0.11, 0.76±0.11 and 0.46±0.07, HMGB1 mRNA was 0.38±0.02, 0.72±0.22 and 0.44±0.08, caspase-1 mRNA was 1.07±0.18, 2.04±0.31 and 0.85±0.54, ASC mRNA was 1.24±0.19, 5.68±0.41 and 3.89±1.47, GSDMD mRNA was 0.79±0.17, 0.94±0.14 and 0.61±0.08, IL-18 mRNA was 0.83±0.27, 4.17±0.79 and 3.57±0.03, respectively. The expression of IL-1β, IL-6, TNF-α, HMGB1, caspase-1, ASC, and IL-18 mRNA in lung tissue was significantly increased in ANP group compared to the CON group; conversely, ABX group showed a significant decrease in the expression of these markers compared to ANP group; and all the differences were statistically significant (all P values <0.05). The protein level of caspase-1 in lung tissue of CON, ANP and ABX group was 1.59±0.51, 2.28±0.13, 1.38±0.47, and that of GSDMD was 1.90±0.09, 2.20±0.07 and 1.76±0.27, respectively, which in ANP group were significantly higher than in CON group, but in ABX group was significantly lower than in ANP group, and all the differences were statistically significant (all P values <0.05). The serum DAO levels of CON, ANP, and ABX group were (0.06±0.15), (0.52±0.11) and (0.58±0.11) ng/ml; the expression level of ileum tissue of claudin1 mRNA and protein was 0.98±0.26, 0.42±0.18, 0.32±0.24 and 1.05±0.08, 0.82±0.09, 0.19±0.04; occludin mRNA and protein was 0.91±0.07, 0.31±0.05, 0.32±0.14 and 1.03±0.07, 0.61±0.04, 0.64±0.11; ZO-1 mRNA and protein was 1.01±0.08, 0.80±0.28, 0.60±0.28, and 0.86±0.10, 0.99±0.30, 0.62±0.30. The serum DAO level was significantly elevated in both ANP and ABX groups compared to the CON group. The mRNA and protein expression of claudin-1 and occludin in both ANP and ABX groups were significantly lower than those in CON group; the expression of claudin-1 in ABX group was significantly downregulated compared to ANP group; and all the differences were statistically significant (all P values <0.05). The relative fluorescence intensities of lung tissue in CON, ANP, and ABX groups were 0.03±0.01, 0.06±0.01, and 0.04±0.01, respectively, which in ANP group was significantly higher compared to CON group, but in ABX group was significantly lower than ANP group; all the differences were statistically significant (all P values <0.05). Conclusions:Intestinal microbiota may attenuate acute pancreatitis-associated acute lung injury by inhibiting the pyroptosis pathway in lung tissue.

Preterm birth (PTB), predominantly induced by intraamniotic inflammation, stands as the foremost contributor to neonatal morbidity and mortality globally. Fetal inflammatory response syndrome, stemming from the activation of the innate immune system, signifies the occurrence of funisitis or chorionic vasculitis. Maternal-fetal complications associated with infection-related PTB encompass maternal sepsis, fetal demise, neonatal sepsis, neonatal neurological impairment, and chronic lung disease. The inflammatory cascade is initiated when Toll-like receptors present on immune cells within the fetal membranes and the female reproductive tract encounter pathogen-associated molecular patterns derived from infectious agents. Subsequently, the nuclear factor kappa-light-chain-enhancer of activated B cells facilitates the transcription of cytokines. The accumulation of neutrophils compromises the tissue integrity of the fetal membranes, leading to membrane rupture via the secretion of matrix metalloproteinases. Elevated prostaglandin levels prompt uterine contractions and cervical remodeling, resulting in progressive cervical effacement and dilation, ultimately culminating in fetal delivery. The diagnosis of PTB should encompass three pivotal criteria: gestational age, uterine activity, and the consequences of that uterine activity. The diagnosis of chorioamnionitis is established through a combination of clinical manifestations, laboratory findings, identification of infectious microorganisms, and placental pathology. Fetal monitoring involves antenatal ultrasonography and non-stress testing. The management of infection-related PTB involves controlling and treating the infection, timing delivery to coincide with optimal fetal lung maturity, and optimizing outcomes for both the mother and neonate. Current preventive strategies for PTB primarily focus on inhibiting myometrial contractions that arise from the inflammatory cascade initiating PTB. An understanding of these pathways serves as the cornerstone for the development of therapeutic interventions aimed at preventing PTB.

Objective:To explore the effects and possible mechanism of intestinal microbiota on lung injury in mice with acute necrotizing pancreatitis (ANP).Methods:The experimental mice were randomly assigned to normal control group (CON group), ANP model group (ANP group) and intestinal germ-free group (ABX group), with 6 mice in each group. The ANP mouse model was constructed by intraperitoneal injection of caerulein (100 μg/kg, for 10 times) at an interval of 1 hour each time, followed by 10 mg/kg lipopolysaccharide injection. Mice in ABX group were treated by Abx solution (0.5 g/L vancomycin, 1 g/L neomycin, 1 g/L metronidazole, and 1 g/L ampicillin), 1 ml/100 g gavage for 28 days before preparation of the ANP model. The CON group was injected intraperitoneally with an equal volume of PBS. Histopathologic examination of the pancreas, lungs, and terminal ileum was routinely performed. Serum amylase levels were measured using enzymatic kinetic chemistry, and serum diamine oxidase (DAO) and lung tissue myeloperoxidase (MPO) activities were measured using ELISA assay. Expression of inflammatory factors, pyroptosis-related molecules in lung tissue and intestinal epithelial tight junction proteins was detected by fluorescence quantitative PCR. Western blotting was used to detect the expression of the pyroptosis molecules caspase-1 and GSDMD in lung tissue, and intestinal epithelial tight junction proteins. Changes of bacterial distribution in lung tissue were measured by fluorescence in situ hybridization. Results:The pathological scores of pancreatic tissue of CON, ANP, and ABX group were (0.67±0.26), (7.33±0.82), and (5.67±0.81); the pathological scores of lung tissue were (1.67±0.41), (5.67±0.41), and (3.58±0.58); the pathological scores of ileal tissue were (0.58±0.52), (3.83±0.75), and (4.33±0.82); the serum amylase levels were (403.95±93.11), (1037.24±126.77), and (647.32±145.90)U/L; the MPO levels in lung tissue were (0.23±0.03), (0.63±0.09), and (0.48±0.05)U/g. ABX group had significantly lower scores in pancreatic and lung tissues, serum amylase levels, and MPO levels in lung tissue compared to ANP group, and all the differences were statistically significant (all P value <0.05). The expression level in pancreatis tissue from CON, ANP and ABX group of IL-1β mRNA was 1.84±0.90, 36.26±5.56 and 16.65±6.43, IL-6 mRNA was 1.07±0.15, 2.90±0.42 and 1.34±0.62, TNF-α mRNA was 0.47±0.11, 0.76±0.11 and 0.46±0.07, HMGB1 mRNA was 0.38±0.02, 0.72±0.22 and 0.44±0.08, caspase-1 mRNA was 1.07±0.18, 2.04±0.31 and 0.85±0.54, ASC mRNA was 1.24±0.19, 5.68±0.41 and 3.89±1.47, GSDMD mRNA was 0.79±0.17, 0.94±0.14 and 0.61±0.08, IL-18 mRNA was 0.83±0.27, 4.17±0.79 and 3.57±0.03, respectively. The expression of IL-1β, IL-6, TNF-α, HMGB1, caspase-1, ASC, and IL-18 mRNA in lung tissue was significantly increased in ANP group compared to the CON group; conversely, ABX group showed a significant decrease in the expression of these markers compared to ANP group; and all the differences were statistically significant (all P values <0.05). The protein level of caspase-1 in lung tissue of CON, ANP and ABX group was 1.59±0.51, 2.28±0.13, 1.38±0.47, and that of GSDMD was 1.90±0.09, 2.20±0.07 and 1.76±0.27, respectively, which in ANP group were significantly higher than in CON group, but in ABX group was significantly lower than in ANP group, and all the differences were statistically significant (all P values <0.05). The serum DAO levels of CON, ANP, and ABX group were (0.06±0.15), (0.52±0.11) and (0.58±0.11) ng/ml; the expression level of ileum tissue of claudin1 mRNA and protein was 0.98±0.26, 0.42±0.18, 0.32±0.24 and 1.05±0.08, 0.82±0.09, 0.19±0.04; occludin mRNA and protein was 0.91±0.07, 0.31±0.05, 0.32±0.14 and 1.03±0.07, 0.61±0.04, 0.64±0.11; ZO-1 mRNA and protein was 1.01±0.08, 0.80±0.28, 0.60±0.28, and 0.86±0.10, 0.99±0.30, 0.62±0.30. The serum DAO level was significantly elevated in both ANP and ABX groups compared to the CON group. The mRNA and protein expression of claudin-1 and occludin in both ANP and ABX groups were significantly lower than those in CON group; the expression of claudin-1 in ABX group was significantly downregulated compared to ANP group; and all the differences were statistically significant (all P values <0.05). The relative fluorescence intensities of lung tissue in CON, ANP, and ABX groups were 0.03±0.01, 0.06±0.01, and 0.04±0.01, respectively, which in ANP group was significantly higher compared to CON group, but in ABX group was significantly lower than ANP group; all the differences were statistically significant (all P values <0.05). Conclusions:Intestinal microbiota may attenuate acute pancreatitis-associated acute lung injury by inhibiting the pyroptosis pathway in lung tissue.

Objective:To observe and evaluate the clinical efficacy and safety of albumin-bound paclitaxel as first-line treatment for patients with advanced pancreatic cancer in China, and to explore the prognosis-related molecules in pancreatic cancer based on next-generation sequencing (NGS) of tumor tissues.Methods:From December 2018 to December 2020, patients with locally advanced or metastatic pancreatic cancer were recruited to accept albumin-bound paclitaxel as first-line treatment in the oncology departments of 24 hospitals in East China. The primary endpoints were overall survival (OS) and treatment related adverse events, and the secondary endpoint was progression-free survival (PFS). Adverse effects were graded using Common Terminology Criteria for Adverse Events 5.0 (CTCAE 5.0). NGS sequencing on the primary or metastatic tissue samples of pancreatic cancer obtained through surgical resection or biopsy was performed.Results:This study recruited 229 patients, including 70 patients with locally advanced pancreatic cancer (LAPC) and 159 patients with metastatic pancreatic cancer (mPC). The disease control rate was 79.9% and the objective response rate is 36.3%.The common adverse effects during treatment were anaemia (159 cases), leucopenia (170 cases), neutropenia (169 cases), increased aminotransferases (110 cases), and thrombocytopenia (95 cases), and the incidence of grade 3-4 neutropenia is 12.2% (28/229). The median follow-up time was 21.2 months (95% CI: 18.5-23.1 months). The median PFS (mPFS) was 5.3 months (95% CI: 4.37-4.07 months) and the median OS (mOS) was 11.2 months (95% CI: 9.5-12.9 months). The mPFS of patients with LAPC was 7.4 months (95% CI: 6.6-11.2 months), and their mOS was 15.5 months (95% CI: 12.6-NA months). The mPFS of patients with mPC was 3.9 months (95% CI: 3.4-5.1 months), and their mOS was 9.3 months (95% CI: 8.0-10.8 months). Multivariate Cox regression analysis showed that clinical stage ( HR=1.47, 95% CI: 1.06-2.04), primary tumor site ( HR=0.64, 95% CI: 0.48-0.86), Eastern Cooperative Oncology Group Performance Status (ECOG PS) score ( HR=2.66, 95% CI: 1.53-4.65), and whether to combine radiotherapy ( HR=0.65, 95% CI: 0.42-1.00) were independent influencing factors for the PFS of these patients. The primary tumor site ( HR=0.68, 95% CI: 0.48-0.95), ECOG score ( HR=5.82, 95% CI: 3.14-10.82), and whether to combine radiotherapy ( HR=0.58, 95% CI: 0.35-0.96) were independent influencing factors of the OS of these patients. The most frequent gene mutations in these advanced stage pancreatic patients were KRAS (89.66%), TP53 (77.01%), CDKN2A (32.18%), and SMAD4 (21.84%) by NGS of tumor tissues from 87 pancreatic cancer patients with sufficient specimens. Further analysis revealed that mutations in CDKN2B, PTEN, FGF6, and RBBP8 genes were significantly associated with an increased risk of death ( P＜0.05). Conclusion:Albumin-bound paclitaxel as first-line treatment demonstrated feasible anti-tumor efficacy and manageable safety for patients with advanced pancreatic cancer in China.

Objective:To observe and evaluate the clinical efficacy and safety of albumin-bound paclitaxel as first-line treatment for patients with advanced pancreatic cancer in China, and to explore the prognosis-related molecules in pancreatic cancer based on next-generation sequencing (NGS) of tumor tissues.Methods:From December 2018 to December 2020, patients with locally advanced or metastatic pancreatic cancer were recruited to accept albumin-bound paclitaxel as first-line treatment in the oncology departments of 24 hospitals in East China. The primary endpoints were overall survival (OS) and treatment related adverse events, and the secondary endpoint was progression-free survival (PFS). Adverse effects were graded using Common Terminology Criteria for Adverse Events 5.0 (CTCAE 5.0). NGS sequencing on the primary or metastatic tissue samples of pancreatic cancer obtained through surgical resection or biopsy was performed.Results:This study recruited 229 patients, including 70 patients with locally advanced pancreatic cancer (LAPC) and 159 patients with metastatic pancreatic cancer (mPC). The disease control rate was 79.9% and the objective response rate is 36.3%.The common adverse effects during treatment were anaemia (159 cases), leucopenia (170 cases), neutropenia (169 cases), increased aminotransferases (110 cases), and thrombocytopenia (95 cases), and the incidence of grade 3-4 neutropenia is 12.2% (28/229). The median follow-up time was 21.2 months (95% CI: 18.5-23.1 months). The median PFS (mPFS) was 5.3 months (95% CI: 4.37-4.07 months) and the median OS (mOS) was 11.2 months (95% CI: 9.5-12.9 months). The mPFS of patients with LAPC was 7.4 months (95% CI: 6.6-11.2 months), and their mOS was 15.5 months (95% CI: 12.6-NA months). The mPFS of patients with mPC was 3.9 months (95% CI: 3.4-5.1 months), and their mOS was 9.3 months (95% CI: 8.0-10.8 months). Multivariate Cox regression analysis showed that clinical stage ( HR=1.47, 95% CI: 1.06-2.04), primary tumor site ( HR=0.64, 95% CI: 0.48-0.86), Eastern Cooperative Oncology Group Performance Status (ECOG PS) score ( HR=2.66, 95% CI: 1.53-4.65), and whether to combine radiotherapy ( HR=0.65, 95% CI: 0.42-1.00) were independent influencing factors for the PFS of these patients. The primary tumor site ( HR=0.68, 95% CI: 0.48-0.95), ECOG score ( HR=5.82, 95% CI: 3.14-10.82), and whether to combine radiotherapy ( HR=0.58, 95% CI: 0.35-0.96) were independent influencing factors of the OS of these patients. The most frequent gene mutations in these advanced stage pancreatic patients were KRAS (89.66%), TP53 (77.01%), CDKN2A (32.18%), and SMAD4 (21.84%) by NGS of tumor tissues from 87 pancreatic cancer patients with sufficient specimens. Further analysis revealed that mutations in CDKN2B, PTEN, FGF6, and RBBP8 genes were significantly associated with an increased risk of death ( P＜0.05). Conclusion:Albumin-bound paclitaxel as first-line treatment demonstrated feasible anti-tumor efficacy and manageable safety for patients with advanced pancreatic cancer in China.

Objective:To investigate the clinical application of three-point wiring localization in mandibular angle osteotomy.Methods:A total of 180 patients with mandibular angle long curve osteotomy were selected in Sichuan Friendship Hospital from July 2021 to April 2022, aged 19-45 (mean age 26.0±10.0) years, including 30 males and 150 females. Preoperative bilateral mandible was symmetry as CT showed, and all of them undergo operation of mandibular angle long curve osteotomy by using three-point wiring localization method under tracheal intubation general anesthesia.Results:Bilateral osteotomy bone of mandibular angle was basically symmetrical in all patients, the arc of osteotomy was good, and there were no obvious complications after surgery. The postoperative follow-up was 3-12 months, and all cases had good postoperative face contour and bilateral symmetry.Conclusions:Using three-point wiring localization method at operation of long curve mandibular angle osteotomy can ensure bilateral symmetry, accuracy and safety of the osteotomy.

Objective:To investigate the application of internal fixation technique using Z-shaped titanium plate during operation of reduction malarplasty.Methods:A retrospective analysis was performed for the clinical data of patients who underwent reduction malarplasty in Sichuan Friendship Hospital from June 2021 to March 2022. The intraoral maxillary vestibular groove mucosal incision and a small incision at the sideburns were used, and according to the height of the zygomatic body to be lowered before surgery, the zygomatic body was inverted F-shaped osteotomy, so that the zygomatic complex anterior was completely loosened. Zygomatic arch anterior to the temporomandibular joint was osteotomy using reciprocating saws and then push inward. The 3-hole titanium plate was bent into a Z-shape, the length of the middle arm of the Z-shaped titanium plate was the distance that the zygomatic arch needs to push inward, for the asymmetry of the zygomatic arch width on both sides, the length of the middle arm of the Z-shaped titanium plate on both sides can be adjusted and fixed with 2 titanium nails. Adjust the anterior zygomatic body so that the osteotomy line was well aligned and fixed with an L-shaped titanium plate. Selected 20 cases with complete three-dimensional(3D) CT data before and 3 months after surgery by random number table, and measured the vertical distance from the outermost point of the zygomatic arch to the median line based on the 3D CT head up position, and the surgical effect was evaluated. SPSS 25.0 software was used to statistically analyze the data, and the quantitative data conforming to the normal distribution were represented by Mean±SD, and the vertical distance from the outermost point of the zygomatic arch to the median line was compared by paired-sample t-test, P<0.05 indicates that the difference is statistically significant. Results:A total of 78 zygomatic plastic surgery patients were enrolled, including 18 males and 60 females, aged 19-37 years old, with an average age of 26 years. All patients’ incision had no complications after surgery, followed up for 3-12 months, the width of the zygomatic arch on both sides was significantly reduced, CT showed that the unilateral zygomatic arch was reduced by 3-8 mm, the transition between the zygomatic and temporal regions was smooth, and the zygomatic arch width on both sides was symmetrical. The difference of the vertical distance from the outermost point of the zygomatic arch to the median line was statistically significant between preoperative and postoperative, on the left side of the patient [(66.5±5.2) mm vs. (61.9±3.2) mm] and [(67.4±4.7) mm vs. (62.1±2.7) mm] ( P<0.05) for the right side. There was no significant difference between the left and right sides after surgery ( P>0.05). Conclusion:The Z-shaped titanium plate internal fixation technique can better control the zygomatic arch internal push distance in reduction malarplasty, and a symmetrical and gentle facial morphology can be obtained after surgery.