Objective To evaluate the clinical efficacy of robot-assisted navigation with percutaneous lag screw treatment for Hangman's fracture.Methods We retrospectively analyzed the clinical data of 5 patients treated with robot-assisted C2 percutaneous lag screw for Hangman's fracture in our hospital from September 2021 to August 2023.Patients were positioned with moderate head-neck flexion in a Mayfield head clamp.After closed reduction with manual traction under general anesthesia,the C2 percutaneous lag screws were implanted under TINAVI orthopedic surgical robot assistance.Postoperative cervical CT scans were used to assess screw placement accuracy and fracture healing quality.Clinical efficacy was evaluated by the Odom grading system.Results All the 5 patients were operated successfully without vertebral artery injury or neurological complications.A total of 10 screws were implanted.According to the Gertzbein-Robbins standard,9 screws belonged to the grade A,and 1 belonged to the grade B,with an accuracy of 90％(9/10)and an excellent rate of 100％(10/10).The neck incision length ranged 20-30 mm(mean,27 mm).The operation time was 86-160 min(mean,112.8 min).The intraoperative blood loss was 10-50 ml(mean,30 ml).The postoperative hospitalization was5-18 d(mean,8 d).The patients were followed up for 12-34 months(mean,23.6 months).All fractures healed without screw breakage or loosening.According to the Odom grading,4 cases were excellent,and 1 case was good.Conclusion Robot-assisted navigation C2 percutaneous lag screw treatment for Hangman's fracture is accurate and minimally invasive,safe and effective.

Objective:To investigate the associations between MRI texture features and genetic mutations in clear cell renal cell carcinoma (ccRCC) and non-ccRCC (n-ccRCC).Methods:This was a cross-section study. A retrospective review was performed on 31 patients (ccRCC group 19 cases and n-ccRCC group 12 cases) diagnosed with renal cell carcinomas and underwent targeted sequencing between April 2011 and December 2021 in the Third Affiliated Hospital of Soochow University. All the patients underwent MRI examinations within two weeks before partial or radical nephrectomy. Texture features were extracted from T 1WI, T 2WI, Dixon-MRI, cortical-medulla phase (CMP), nephrographic phase (NGP), and delayed phase (DEP) images. MRI texture features with the highest value for distinguishing ccRCC from n-ccRCC were selected for subsequent analysis. The next-generation high-throughput sequencing technology was employed to analyze gene mutations in renal tumors. The correlation between mutation genes and texture features in ccRCC and n-ccRCC was analyzed using Spearman correlation coefficient. Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway annotation analysis was performed. Results:A total of 8 MRI texture features were selected. In the ccRCC group, PTEN mutation was correlated with DEP_InverseDifferenceMoment_angle0_offset7 ( r=-0.58, P=0.009). In the non-ccRCC group, SETD2 mutation was correlated with CM_Phase_InverseDifferenceMoment_AllDirection_offset1 and Dixon_W_InverseDifferenceMoment_AllDirection_offset7 ( r=0.58, 0.63, P=0.048, 0.027), PBRM1 mutation was correlated with DE_Phase_InverseDifferenceMoment_angle0_offset7 and DE_Phase_HaraVariance ( r=0.61, -0.60, P=0.034, 0.039), and FAT1 mutation was correlated with DE_Phase_HaraVariance and NG_Phase_Inertia_angle135_offset4 ( r=0.58, 0.58, P=0.047, 0.047). The KEGG pathway annotation analysis showed that the mechanisms of the mutation genes that correlated with MRI texture features in the ccRCC group were related to the p53 signaling pathway, inositol phosphate metabolism, central carbon metabolism in cancer, EGFR tyrosine kinase inhibitor resistance, PD-L1 expression and PD-1 checkpoint pathway in cancer, and phosphatidylinositol signaling system. The mutation genes correlated with MRI texture features in the non-ccRCC group were mainly associated with lysine degradation. Conclusion:The associations are found between MRI texture features and underlying genetic mutations of ccRCC and n-ccRCC. These mutation genes have completely different enrichment pathways.

Objective:To explore the value of four-dimensional flow (4D Flow) MRI in evaluating hemodynamic changes of transplant renal artery stenosis (TRAS).Methods:The study was a cross-sectional study. A retrospective analysis of 67 patients after renal transplantation was performed in Third Affiliated Hospital of Soochow University from January 2021 to October 2022. All patients were examined with non-contrast enhanced magnetic resonance angiography (NCE-MRA) and 4D Flow MRI. After NCE-MRA assessment, the patients were divided into a non stenosis group (39 cases), non-obvious stenosis group (stenosis degree<50%, 13 cases) and obvious stenosis group (stenosis degree≥50%, 15 cases). The 4D Flow MRI data were analyzed using the post-processing software CVI42 (Canada) to measure hemodynamic parameters of the transplanted renal artery in the non-stenosis group, as well as the proximal, central, and distal regions of the stenosis in the non-obvious stenosis group and obvious stenosis group. The parameters included net flow rate, maximum flow rate, average velocity, peak velocity, average wall shear stress, and maximum wall shear stress. One way analysis of variance and least significant difference (LSD) were used to test the differences of hemodynamic parameters among the three groups and between the proximal, central and distal regions of the stenosis. Pearson correlation coefficient was used to evaluate the correlation between hemodynamic parameters of transplant renal artery and estimated glomerular filtration rate (eGFR).Results:The net flow, maximum flow and average velocity at the proximal region of stenosis in the group with obvious stenosis of transplanted renal artery were significantly lower than those in the non-stenosis group and the non-obvious stenosis group (all P<0.05). The net flow and maximum flow at the distal region of stenosis in both obvious stenosis group and non-obvious stenosis group were lower than those in non-stenosis group, and the differences were statistically significant (both P<0.001). The mean velocity and peak velocity at the distal region of stenosis in the obvious stenosis group were higher than those in the non-stenosis group, and the differences were statistically significant (both P<0.05). The maximum and average wall shear stress at the distal region of stenosis in the obvious stenosis group were lower than those in the non-stenosis group and the non-obvious stenosis group, and the differences were statistically significant (both P<0.05). The net flow and maximum flow in the center region of stenosis were lower than those in the proximal region of stenosis, and the differences were statistically significant (both P<0.05). The peak velocity in the center region and distal region of stenosis was higher than those in the proximal region of stenosis, and the difference was statistically significant (both P<0.05). There was a positive correlation between the net flow and eGFR at the TRAS patients proximal, center, and distal stenosis ( r=0.270, 0.260, 0.320, respectively, P=0.044, 0.041, 0.036, respectively). There was a positive correlation between the maximum flow and eGFR at the TRAS patients proximal, center, and distal stenosis ( r=0.306, 0.276, 0.269, respectively, P=0.037, 0.041, 0.043, respectively). Conclusion:After TRAS, there is a significant change in blood flow status. The 4D Flow MRI can provide quantitative hemodynamic parameters to reflect the hemodynamic changes of TRAS.

Objective To evaluate the clinical efficacy of robot-assisted navigation with percutaneous lag screw treatment for Hangman's fracture.Methods We retrospectively analyzed the clinical data of 5 patients treated with robot-assisted C2 percutaneous lag screw for Hangman's fracture in our hospital from September 2021 to August 2023.Patients were positioned with moderate head-neck flexion in a Mayfield head clamp.After closed reduction with manual traction under general anesthesia,the C2 percutaneous lag screws were implanted under TINAVI orthopedic surgical robot assistance.Postoperative cervical CT scans were used to assess screw placement accuracy and fracture healing quality.Clinical efficacy was evaluated by the Odom grading system.Results All the 5 patients were operated successfully without vertebral artery injury or neurological complications.A total of 10 screws were implanted.According to the Gertzbein-Robbins standard,9 screws belonged to the grade A,and 1 belonged to the grade B,with an accuracy of 90％(9/10)and an excellent rate of 100％(10/10).The neck incision length ranged 20-30 mm(mean,27 mm).The operation time was 86-160 min(mean,112.8 min).The intraoperative blood loss was 10-50 ml(mean,30 ml).The postoperative hospitalization was5-18 d(mean,8 d).The patients were followed up for 12-34 months(mean,23.6 months).All fractures healed without screw breakage or loosening.According to the Odom grading,4 cases were excellent,and 1 case was good.Conclusion Robot-assisted navigation C2 percutaneous lag screw treatment for Hangman's fracture is accurate and minimally invasive,safe and effective.

Objective:To investigate the associations between MRI texture features and genetic mutations in clear cell renal cell carcinoma (ccRCC) and non-ccRCC (n-ccRCC).Methods:This was a cross-section study. A retrospective review was performed on 31 patients (ccRCC group 19 cases and n-ccRCC group 12 cases) diagnosed with renal cell carcinomas and underwent targeted sequencing between April 2011 and December 2021 in the Third Affiliated Hospital of Soochow University. All the patients underwent MRI examinations within two weeks before partial or radical nephrectomy. Texture features were extracted from T 1WI, T 2WI, Dixon-MRI, cortical-medulla phase (CMP), nephrographic phase (NGP), and delayed phase (DEP) images. MRI texture features with the highest value for distinguishing ccRCC from n-ccRCC were selected for subsequent analysis. The next-generation high-throughput sequencing technology was employed to analyze gene mutations in renal tumors. The correlation between mutation genes and texture features in ccRCC and n-ccRCC was analyzed using Spearman correlation coefficient. Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway annotation analysis was performed. Results:A total of 8 MRI texture features were selected. In the ccRCC group, PTEN mutation was correlated with DEP_InverseDifferenceMoment_angle0_offset7 ( r=-0.58, P=0.009). In the non-ccRCC group, SETD2 mutation was correlated with CM_Phase_InverseDifferenceMoment_AllDirection_offset1 and Dixon_W_InverseDifferenceMoment_AllDirection_offset7 ( r=0.58, 0.63, P=0.048, 0.027), PBRM1 mutation was correlated with DE_Phase_InverseDifferenceMoment_angle0_offset7 and DE_Phase_HaraVariance ( r=0.61, -0.60, P=0.034, 0.039), and FAT1 mutation was correlated with DE_Phase_HaraVariance and NG_Phase_Inertia_angle135_offset4 ( r=0.58, 0.58, P=0.047, 0.047). The KEGG pathway annotation analysis showed that the mechanisms of the mutation genes that correlated with MRI texture features in the ccRCC group were related to the p53 signaling pathway, inositol phosphate metabolism, central carbon metabolism in cancer, EGFR tyrosine kinase inhibitor resistance, PD-L1 expression and PD-1 checkpoint pathway in cancer, and phosphatidylinositol signaling system. The mutation genes correlated with MRI texture features in the non-ccRCC group were mainly associated with lysine degradation. Conclusion:The associations are found between MRI texture features and underlying genetic mutations of ccRCC and n-ccRCC. These mutation genes have completely different enrichment pathways.

Objective:To explore the value of four-dimensional flow (4D Flow) MRI in evaluating hemodynamic changes of transplant renal artery stenosis (TRAS).Methods:The study was a cross-sectional study. A retrospective analysis of 67 patients after renal transplantation was performed in Third Affiliated Hospital of Soochow University from January 2021 to October 2022. All patients were examined with non-contrast enhanced magnetic resonance angiography (NCE-MRA) and 4D Flow MRI. After NCE-MRA assessment, the patients were divided into a non stenosis group (39 cases), non-obvious stenosis group (stenosis degree<50%, 13 cases) and obvious stenosis group (stenosis degree≥50%, 15 cases). The 4D Flow MRI data were analyzed using the post-processing software CVI42 (Canada) to measure hemodynamic parameters of the transplanted renal artery in the non-stenosis group, as well as the proximal, central, and distal regions of the stenosis in the non-obvious stenosis group and obvious stenosis group. The parameters included net flow rate, maximum flow rate, average velocity, peak velocity, average wall shear stress, and maximum wall shear stress. One way analysis of variance and least significant difference (LSD) were used to test the differences of hemodynamic parameters among the three groups and between the proximal, central and distal regions of the stenosis. Pearson correlation coefficient was used to evaluate the correlation between hemodynamic parameters of transplant renal artery and estimated glomerular filtration rate (eGFR).Results:The net flow, maximum flow and average velocity at the proximal region of stenosis in the group with obvious stenosis of transplanted renal artery were significantly lower than those in the non-stenosis group and the non-obvious stenosis group (all P<0.05). The net flow and maximum flow at the distal region of stenosis in both obvious stenosis group and non-obvious stenosis group were lower than those in non-stenosis group, and the differences were statistically significant (both P<0.001). The mean velocity and peak velocity at the distal region of stenosis in the obvious stenosis group were higher than those in the non-stenosis group, and the differences were statistically significant (both P<0.05). The maximum and average wall shear stress at the distal region of stenosis in the obvious stenosis group were lower than those in the non-stenosis group and the non-obvious stenosis group, and the differences were statistically significant (both P<0.05). The net flow and maximum flow in the center region of stenosis were lower than those in the proximal region of stenosis, and the differences were statistically significant (both P<0.05). The peak velocity in the center region and distal region of stenosis was higher than those in the proximal region of stenosis, and the difference was statistically significant (both P<0.05). There was a positive correlation between the net flow and eGFR at the TRAS patients proximal, center, and distal stenosis ( r=0.270, 0.260, 0.320, respectively, P=0.044, 0.041, 0.036, respectively). There was a positive correlation between the maximum flow and eGFR at the TRAS patients proximal, center, and distal stenosis ( r=0.306, 0.276, 0.269, respectively, P=0.037, 0.041, 0.043, respectively). Conclusion:After TRAS, there is a significant change in blood flow status. The 4D Flow MRI can provide quantitative hemodynamic parameters to reflect the hemodynamic changes of TRAS.

Objective:To explore the feasibility of chemical exchange saturation transfer (CEST) imaging at 3.0 T MRI in quantifying renal redox metabolism in vitro models and experimental animals.Methods:Redox metabolites in vitro models with physiological concentrations were prepared, including reduced metabolites (glutamate, alanine, glutathione) and oxidized metabolites (2-ketoglutarate, pyruvate, glutathione disulfide, ammonium hydroxide). CEST examinations were performed at 3.0 T MRI. The imaging parameters were as follows: CEST images with different saturation pulse intensity (B 1) (1, 2, 3, 4 μT) and a fixed radio frequency (RF) duration of 2 000 ms; CEST images with different RF durations (1 500 and 2 000 ms) were acquired with a fixed B 1 value of 2 μT to obtain the optimal scanning parameters. CEST examinations with optimized parameters were performed on the left kidneys of seven healthy rabbits, and the differences in magnetic resonance ratio asymmetry (MTR asym) between rabbit renal cortex and outer medulla were measured. A paired t-test was used to compare the differences. Results:The optimal B 1 for CEST examination of redox metabolites was 2 μT, and the optimal RF duration was 2 000 ms. The MTR asym peaks of glutathione disulfide, glutathione, glutamic acid, and alanine were at 3.75, 3.5, 3, and 1.5 ppm, respectively. The MTR asym peaks of pyruvate, 2-ketoglutarate, and ammonium hydroxide were at 1 ppm. The MTR asym peak values of reduced metabolites were higher than those of oxidized metabolites. When the B 1 value was 2 μT and the RF duration was 2 000 ms, the MTR asym signal of the renal cortex was (2.60±1.10) %, (2.86±1.32) %, (3.04±1.06) %, and (2.98±0.91) % at 1, 3, 3.5, and 3.75 ppm, respectively. The MTR asym signal of the outer medulla was (1.00±0.56) %, (2.43±0.94) %, (2.29±0.88) % and (1.98±0.58) %, respectively. The MTR asym signal of the renal cortex was higher than that of the outer medulla, and the differences were statistically significant ( t=3.04, P=0.023; t=2.56, P=0.043; t=3.50, P=0.013; t=3.45, P=0.014). Conclusion:CEST imaging at 3.0 T MRI can be used to quantitatively evaluate redox metabolism of healthy rabbit kidneys in vitro model and normal experimental rabbits.

Objective:To investigate the feasibility of 3.0 T glutamate chemical exchange saturation transfer (GluCEST) imaging in evaluating renal redox metabolism in renal ischemia-reperfusion injury (IRI).Methods:Rabbits in the IRI group ( n=56) underwent surgery by clamping the left renal artery for 45 min and then releasing to establish IRI. Rabbits in the sham group ( n=8) underwent the same operation without clamping the left renal artery. GluCEST MRI was performed before and at 1 h, 12 h, 1 day, 3 days, 7 days, and 14 days after the operations, with eight rabbits in the IRI group sacrificed immediately after each scanning and eight in the sham group sacrificed at 14 days after scanning. The left kidneys were removed for histopathological examination and reactive oxygen species (ROS) fluorescence staining. Differences in the magnetic resonance ratio asymmetry (MTR asym) of the renal cortex and outer medulla among different groups were compared. Correlations between the MTR asym and ROS were analyzed. Results:The MTR asym of the renal cortex in the sham and IRI subgroups were higher than that of the outer medulla ( t=8.16, P<0.001; t=4.78, P=0.002; t=4.94, P=0.002; t=5.76, P=0.001, t=6.68, P<0.001; t=6.40, P<0.001; t=5.16, P=0.001; t=3.30, P=0.013). The MTR asym of the renal cortex and outer medulla in the IRI-1h, IRI-12h, IRI-1d, IRI-3d, IRI-7d, and IRI-14d groups were lower than in the sham and IRI-pre groups (all P<0.05). The MTR asym of the renal cortex and outer medulla in the IRI-1h group were lower than in the IRI-12h, IRI-1d, IRI-3d, IRI-7d, and IRI-14d groups (all P<0.05). The MTR asym of the renal cortex in the IRI-12h group was lower than in the IRI-7d and IRI-14d groups (1.84%±0.09% vs.2.42%±0.19%, 2.41%±0.31%, all P<0.05). The MTR asym of the renal cortex in the IRI-1d group was lower than in the IRI-7d group (1.99%±0.17% vs. 2.42%±0.19%, P=0.008). The MTR asym of the outer medulla in the IRI-12h group was lower than in the IRI-3d, IRI-7d, and IRI-14d groups (1.32%±0.27% vs. 1.79%±0.31%, 1.98%±0.18%, 1.66%±0.40%, respectively, all P<0.05]. The MTR asym of the outer medulla in the IRI-7d group was higher than in the IRI-1d and IRI-14d groups (1.98%±0.18% vs. 1.52%±0.31%, 1.66%±0.40%, all P<0.05). The MTR asym of the renal cortex and outer medulla had a strong negative correlation with the mean fluorescence intensity of ROS ( ρ=-0.889, P<0.001; ρ=-0.784, P<0.001). Conclusion:3.0 T GluCEST imaging can indirectly reflect the changes of renal redox metabolism in renal IRI.

Objective:A nationwide multi-center and large sample survey was conducted to compare the validity of the Mini International Neuropsychiatric Interview (Hypo-) Manic Episode with Mixed Features-DSM-5 Module (MINI-M) questionnaire and the Clinically Useful Depression Outcome Scale Supplemented with Questions for the DSM-5 Mixed Features Specifier (CUDOS-M) depression subscale in identifying mixed features in patients experiencing (hypo-) manic episodes.Methods:Using a convenience sampling method, 366 patients with bipolar disorder experiencing acute (hypo-) manic episodes who met the inclusion and exclusion criteria were recruited. The diagnosis of "with mixed features" was based on the DSM-5 criteria for mixed features. The predictive validity of the MINI-M questionnaire and the CUDOS-M depression subscale to screen mixed features was analyzed using the receiver operating characteristic (ROC) curve. Additionally, the difference in area under the ROC curve (AUC) between the two instruments was compared.Results:The AUC for the MINI-M questionnaire and the CUDOS-M depression subscale in screening mixed features were 0.79 (95 %CI=0.75-0.84) and 0.81 (95 %CI=0.77-0.86), respectively. There was no statistically significant difference in AUC between the two measurements ( Z=-1.19, P>0.05). Among patients with acute (hypo-) manic episodes, 45.9% (168/366) presented with mixed features according to the DSM-5 criteria, while the corresponding figures were 43.7% (160/366) using the MINI-M questionnaire (total score≥3) and 42.1% (154/366) using the CUDOS-M depression subscale (total score≥20). Screening results were comparable among the three measures. Conclusion:Mixed features are common among patients experiencing acute (hypo-) manic episodes. The MINI-M questionnaire and the CUDOS-M depression subscale demonstrate equivalent validity in identifying mixed features.

Objective:A nationwide multi-center and large sample survey was conducted to compare the validity of the Mini International Neuropsychiatric Interview (Hypo-) Manic Episode with Mixed Features-DSM-5 Module (MINI-M) questionnaire and the Clinically Useful Depression Outcome Scale Supplemented with Questions for the DSM-5 Mixed Features Specifier (CUDOS-M) depression subscale in identifying mixed features in patients experiencing (hypo-) manic episodes.Methods:Using a convenience sampling method, 366 patients with bipolar disorder experiencing acute (hypo-) manic episodes who met the inclusion and exclusion criteria were recruited. The diagnosis of "with mixed features" was based on the DSM-5 criteria for mixed features. The predictive validity of the MINI-M questionnaire and the CUDOS-M depression subscale to screen mixed features was analyzed using the receiver operating characteristic (ROC) curve. Additionally, the difference in area under the ROC curve (AUC) between the two instruments was compared.Results:The AUC for the MINI-M questionnaire and the CUDOS-M depression subscale in screening mixed features were 0.79 (95 %CI=0.75-0.84) and 0.81 (95 %CI=0.77-0.86), respectively. There was no statistically significant difference in AUC between the two measurements ( Z=-1.19, P>0.05). Among patients with acute (hypo-) manic episodes, 45.9% (168/366) presented with mixed features according to the DSM-5 criteria, while the corresponding figures were 43.7% (160/366) using the MINI-M questionnaire (total score≥3) and 42.1% (154/366) using the CUDOS-M depression subscale (total score≥20). Screening results were comparable among the three measures. Conclusion:Mixed features are common among patients experiencing acute (hypo-) manic episodes. The MINI-M questionnaire and the CUDOS-M depression subscale demonstrate equivalent validity in identifying mixed features.