Objective:To investigate the value of biparametric-MRI (bpMRI) based peritumoral radiomics for preoperative prediction of extraprostatic extension (EPE) in prostate cancer (PCa).Methods:In this cross-sectional study, consecutive bpMRI of patients undergoing prostatectomy for PCa were retrospectively collected from the First Medical Center (center 1) and the Third Medical Center (center 2) of Chinese PLA General Hospital. A total of 274 patients were finally enrolled. Patients at center 1 from January 2020 to December 2022 were randomly divided into a training set (149 cases) and an internal validation set (63 cases) by stratified random sampling. Patients at center 2 from January 2023 to March 2024 were assigned to the external test set (62 cases). Patients were categorized into EPE-positive group and EPE-negative group according to pathological assessment postoperatively. In the training set, there were 49 cases in EPE-positive group and 100 cases in EPE-negative group. In the internal validation set, there were 26 cases in EPE-positive group and 37 cases in EPE-negative group. In the external test set, there were 22 cases in EPE-positive group and 40 cases in EPE-negative group. Axial T 2WI and apparent diffusion coefficient (ADC) images were manually annotated to obtain index lesion regions of interest (ROIs), with the peritumoral ROIs subsequently delineated by semi-automatic segmentation technique. Radiomics features were extracted from intra-tumoral, peri-tumoral, and intra-tumoral plus peri-tumoral ROIs. The training set data was employed to select and optimize features to build the radiomics models. The logistic regression analysis was used to develop radiomics, clinical, and integrated models. The predictive performance was assessed by the area under the receiver operating characteristic curve (AUC) in the external test set, and compared by the DeLong test. The sensitivity and specificity were compared by the exact McNemar test. Results:In the external test set, the peri-tumoral radiomics model based on bpMRI showed the highest performance in evaluating EPE, with an AUC of 0.739 (95% CI 0.611-0.842), which was identified as the optimal radiomics model. EPE grade ( OR=6.151, 95% CI 3.371-11.226, P<0.001) was incorporated into the clinical model, with an AUC of 0.780 (95% CI 0.657-0.875) in the external test set. The integrated model had an AUC of 0.817 (95% CI 0.698-0.904) in the external test set. There was no statistically significant difference in comparisons of AUCs among the three models (all P>0.05). The sensitivity of the integrated model (68.2%) showed no significant difference from those of the clinical model and the optimal radiomics model (77.3% and 86.4%, respectively; P=0.500 and P=0.289). However, the specificity of the integrated model (85.0%) was significantly higher than those of the clinical model (67.5%, P=0.016) and the optimal radiomics model (50.0%, P<0.001). Conclusion:A bpMRI-based peritumoral radiomics integrating clinical model demonstrates high performance for preoperative prediction of EPE in PCa.

Objective:To evaluate the efficacy of preoperative prediction of regional lymph node (RLN) metastasis in renal cell carcinoma (RCC) using a machine learning model based on habitat imaging radiomics from renal MRI.Methods:This cross-sectional study retrospectively analyzed 220 patients with RCC who underwent nephrectomy and RLN dissection at four medical centers of Chinese PLA General Hospital from January 2010 to August 2023. The cohort included 65 patients with RLN metastasis and 155 without. A stratified random sampling method was used to divide 175 patients from the first medical center into a training set ( n=140) and an internal test set ( n=35) in an 8∶2 ratio, while 45 patients from the third, fourth, and fifth medical centers constituted the external test set. The primary RCC lesions were categorized into 15 habitat subregions based on corticomedullary-phase enhancement and T 2WI signal intensity on MRI, and the volume fractions of different subregions were analyzed. In the training cohort, radiomics features derived from the habitat subregions were used to construct a radiomics model employing various machine learning algorithms, including extremely random trees (ET), gradient boosting decision trees (GBDT), random forest (RF), and support vector machine (SVM). The optimal model was selected and combined with RLN short-axis diameter to develop a combined model. The efficacy of each model in predicting RLN metastasis was evaluated using the receiver operating characteristic (ROC) curve. Results:The volume fraction of hyper-enhanced hyper-intense regions in the non-metastatic group was significantly higher than that in the metastatic group (0.05±0.09 vs. 0.02±0.03; t=3.00, P=0.003). Among the machine learning models constructed using 15 optimal habitat radiomics features, the SVM model demonstrated the best performance, with area under the ROC curve (AUC) values of 0.85 (95% CI 0.72-0.98) in the internal test set and 0.82 (95% CI 0.67-0.98) in the external test set, surpassing those of the ET, GBDT, and RF models. The combined model, integrating the SVM model with RLN short-axis diameter, achieved AUC values of 0.94 (95% CI 0.85-1.00) in the internal test set and 0.89 (95% CI 0.78-1.00) in the external test set, with RLN short-axis diameter contributing AUC values of 0.81 (95% CI 0.66-0.96) and 0.81 (95% CI 0.68-0.94), respectively. The diagnostic sensitivity of the combined model was 91.7% in the internal test set and 85.7% in the external test set, with specificities of 78.3% and 67.7%, respectively. Conclusion:The combined model based on MRI habitat imaging radiomics and RLN short-axis diameter demonstrates excellent preoperative assessment capability for RLN metastasis in RCC.

Objective To investigate the application value of conventional MRI combined with diffusion tensor imaging(DTI)in evaluating the correlation between the texture composition of benign prostatic hyperplasia(BPH)and the International Prostate Symptom Score(IPSS).Methods Seventy patients with BPH confirmed by pathology were retrospectively analyzed and all patients underwent conventional MRI,DTI and IPSS before surgery.Evaluation metrics included:the mean signal intensity of T2WI(mean-SI-T2WI),apparent diffusion coefficient(ADC)and fractional anisotropy(FA)values.Independent samples t-test,partial correlation analysis,and receiver operating characteristic(ROC)curve were used to assess the correlation between the texture parameters of the prostate transition zone and IPSS.Results The mean-SI-T2WI was significantly negatively correlated with IPSS(r=-0.683,P<0.001);the average ADC value was slightly negatively correlated with IPSS(r=-0.467,P<0.001);and the average FA value was slightly positively correlated with IPSS(r=0.419,P<0.001).The predictive value of MRI texture parameters for IPSS in BPH patients,ranked from high to low,mean-SI-T2WI[area under the curve(AUC)=0.734],average ADC value(AUC=0.673),and average FA value(AUC=0.635);However,the combination of mean-SI-T2WI+ADC+FA(AUC=0.791)did not significantly improve the diagnostic efficacy by DeLong's test(P>0.05).Conclusion Mean-SI-T2WI,DWI and DTI can be used to evaluate the composition of the prostate,among which mean-SI-T2WI is the best,and the com-bination of them can not improve the diagnostic efficacy.

Objective:To explore the efficacy of the fifth metatarsal perforator flap of the lateral plantar artery in repairing the wounds on the anterolateral side of the foot.Methods:This study was a retrospective observational study. Eight patients with skin and soft tissue defects on the anterolateral side of the foot and conformed to the inclusion criteria were admitted to the Department of Plastic Surgery of Hanzhong Central Hospital from July 2020 to July 2023. There were 6 males and 2 females, aged 22 to 72 years. Among the patients, there were three patients with electrical burns, four patients with trauma, and one patient with plantar wart. Preoperatively, a Doppler blood flow detector was used to clarify the number and location of the fifth metatarsal perforating vessels. The area of the wounds measured during the operation ranged from 4.0 cm×3.0 cm to 7.0 cm×5.0 cm, and the fifth metatarsal perforator flaps of the lateral plantar artery with area of 4.0 cm×4.0 cm to 9.0 cm×6.0 cm were designed and harvested to repair the wounds. The wounds in the flap donor sites were repaired with medium-thickness skin grafts from lower limb on the same side. The duration of surgery and intraoperative blood loss volume were recorded. The survivals of the transplanted flap and skin graft were observed after surgery. At the last follow-up, the appearance of the flap and the occurrence of complication were observed, the two-point discrimination distance of the flap was measured, and the shape of the flap donor site as well as the sensation and other functions of the affected foot were observed.Results:The duration of surgery ranged from 70 to 100 min, with an average of 84.6 min. The intraoperative blood loss volume ranged from 30 to 80 mL, with an average of 53.5 mL. After surgery, all flaps survived completely; only one patient developed partial necrosis of the skin graft in the wound in flap donor site, and the wound healed completely after dressing change and re-grafting medium-thickness skin graft from lower limb on the same side. Postoperative follow-up was conducted for 6 to 24 months, with an average of 13.8 months. At the last follow-up, none of the patients developed bloated and deformed flaps or pressure ulcers, and the two-point discrimination distance of the flap ranged from 5 to 13 mm. No tendon adhesion or scar hyperplasia was observed in the flap donor sites, and the sensation, weight-bearing, and walking functions of the affected feet were normal.Conclusions:The use of the fifth metatarsal perforator flap of the lateral plantar artery for repairing the wounds on the anterolateral side of the foot has the advantages of flexible flap design, minimal damage to the flap donor site, simple and feasible surgical operation, and good postoperative foot appearance and function, which is worthy of clinical application and promotion.

Objective:To investigate the value of biparametric-MRI (bpMRI) based peritumoral radiomics for preoperative prediction of extraprostatic extension (EPE) in prostate cancer (PCa).Methods:In this cross-sectional study, consecutive bpMRI of patients undergoing prostatectomy for PCa were retrospectively collected from the First Medical Center (center 1) and the Third Medical Center (center 2) of Chinese PLA General Hospital. A total of 274 patients were finally enrolled. Patients at center 1 from January 2020 to December 2022 were randomly divided into a training set (149 cases) and an internal validation set (63 cases) by stratified random sampling. Patients at center 2 from January 2023 to March 2024 were assigned to the external test set (62 cases). Patients were categorized into EPE-positive group and EPE-negative group according to pathological assessment postoperatively. In the training set, there were 49 cases in EPE-positive group and 100 cases in EPE-negative group. In the internal validation set, there were 26 cases in EPE-positive group and 37 cases in EPE-negative group. In the external test set, there were 22 cases in EPE-positive group and 40 cases in EPE-negative group. Axial T 2WI and apparent diffusion coefficient (ADC) images were manually annotated to obtain index lesion regions of interest (ROIs), with the peritumoral ROIs subsequently delineated by semi-automatic segmentation technique. Radiomics features were extracted from intra-tumoral, peri-tumoral, and intra-tumoral plus peri-tumoral ROIs. The training set data was employed to select and optimize features to build the radiomics models. The logistic regression analysis was used to develop radiomics, clinical, and integrated models. The predictive performance was assessed by the area under the receiver operating characteristic curve (AUC) in the external test set, and compared by the DeLong test. The sensitivity and specificity were compared by the exact McNemar test. Results:In the external test set, the peri-tumoral radiomics model based on bpMRI showed the highest performance in evaluating EPE, with an AUC of 0.739 (95% CI 0.611-0.842), which was identified as the optimal radiomics model. EPE grade ( OR=6.151, 95% CI 3.371-11.226, P<0.001) was incorporated into the clinical model, with an AUC of 0.780 (95% CI 0.657-0.875) in the external test set. The integrated model had an AUC of 0.817 (95% CI 0.698-0.904) in the external test set. There was no statistically significant difference in comparisons of AUCs among the three models (all P>0.05). The sensitivity of the integrated model (68.2%) showed no significant difference from those of the clinical model and the optimal radiomics model (77.3% and 86.4%, respectively; P=0.500 and P=0.289). However, the specificity of the integrated model (85.0%) was significantly higher than those of the clinical model (67.5%, P=0.016) and the optimal radiomics model (50.0%, P<0.001). Conclusion:A bpMRI-based peritumoral radiomics integrating clinical model demonstrates high performance for preoperative prediction of EPE in PCa.

Objective To investigate the application value of conventional MRI combined with diffusion tensor imaging(DTI)in evaluating the correlation between the texture composition of benign prostatic hyperplasia(BPH)and the International Prostate Symptom Score(IPSS).Methods Seventy patients with BPH confirmed by pathology were retrospectively analyzed and all patients underwent conventional MRI,DTI and IPSS before surgery.Evaluation metrics included:the mean signal intensity of T2WI(mean-SI-T2WI),apparent diffusion coefficient(ADC)and fractional anisotropy(FA)values.Independent samples t-test,partial correlation analysis,and receiver operating characteristic(ROC)curve were used to assess the correlation between the texture parameters of the prostate transition zone and IPSS.Results The mean-SI-T2WI was significantly negatively correlated with IPSS(r=-0.683,P<0.001);the average ADC value was slightly negatively correlated with IPSS(r=-0.467,P<0.001);and the average FA value was slightly positively correlated with IPSS(r=0.419,P<0.001).The predictive value of MRI texture parameters for IPSS in BPH patients,ranked from high to low,mean-SI-T2WI[area under the curve(AUC)=0.734],average ADC value(AUC=0.673),and average FA value(AUC=0.635);However,the combination of mean-SI-T2WI+ADC+FA(AUC=0.791)did not significantly improve the diagnostic efficacy by DeLong's test(P>0.05).Conclusion Mean-SI-T2WI,DWI and DTI can be used to evaluate the composition of the prostate,among which mean-SI-T2WI is the best,and the com-bination of them can not improve the diagnostic efficacy.

Objective:To explore the efficacy of the fifth metatarsal perforator flap of the lateral plantar artery in repairing the wounds on the anterolateral side of the foot.Methods:This study was a retrospective observational study. Eight patients with skin and soft tissue defects on the anterolateral side of the foot and conformed to the inclusion criteria were admitted to the Department of Plastic Surgery of Hanzhong Central Hospital from July 2020 to July 2023. There were 6 males and 2 females, aged 22 to 72 years. Among the patients, there were three patients with electrical burns, four patients with trauma, and one patient with plantar wart. Preoperatively, a Doppler blood flow detector was used to clarify the number and location of the fifth metatarsal perforating vessels. The area of the wounds measured during the operation ranged from 4.0 cm×3.0 cm to 7.0 cm×5.0 cm, and the fifth metatarsal perforator flaps of the lateral plantar artery with area of 4.0 cm×4.0 cm to 9.0 cm×6.0 cm were designed and harvested to repair the wounds. The wounds in the flap donor sites were repaired with medium-thickness skin grafts from lower limb on the same side. The duration of surgery and intraoperative blood loss volume were recorded. The survivals of the transplanted flap and skin graft were observed after surgery. At the last follow-up, the appearance of the flap and the occurrence of complication were observed, the two-point discrimination distance of the flap was measured, and the shape of the flap donor site as well as the sensation and other functions of the affected foot were observed.Results:The duration of surgery ranged from 70 to 100 min, with an average of 84.6 min. The intraoperative blood loss volume ranged from 30 to 80 mL, with an average of 53.5 mL. After surgery, all flaps survived completely; only one patient developed partial necrosis of the skin graft in the wound in flap donor site, and the wound healed completely after dressing change and re-grafting medium-thickness skin graft from lower limb on the same side. Postoperative follow-up was conducted for 6 to 24 months, with an average of 13.8 months. At the last follow-up, none of the patients developed bloated and deformed flaps or pressure ulcers, and the two-point discrimination distance of the flap ranged from 5 to 13 mm. No tendon adhesion or scar hyperplasia was observed in the flap donor sites, and the sensation, weight-bearing, and walking functions of the affected feet were normal.Conclusions:The use of the fifth metatarsal perforator flap of the lateral plantar artery for repairing the wounds on the anterolateral side of the foot has the advantages of flexible flap design, minimal damage to the flap donor site, simple and feasible surgical operation, and good postoperative foot appearance and function, which is worthy of clinical application and promotion.

Objective:To evaluate the efficacy of preoperative prediction of regional lymph node (RLN) metastasis in renal cell carcinoma (RCC) using a machine learning model based on habitat imaging radiomics from renal MRI.Methods:This cross-sectional study retrospectively analyzed 220 patients with RCC who underwent nephrectomy and RLN dissection at four medical centers of Chinese PLA General Hospital from January 2010 to August 2023. The cohort included 65 patients with RLN metastasis and 155 without. A stratified random sampling method was used to divide 175 patients from the first medical center into a training set ( n=140) and an internal test set ( n=35) in an 8∶2 ratio, while 45 patients from the third, fourth, and fifth medical centers constituted the external test set. The primary RCC lesions were categorized into 15 habitat subregions based on corticomedullary-phase enhancement and T 2WI signal intensity on MRI, and the volume fractions of different subregions were analyzed. In the training cohort, radiomics features derived from the habitat subregions were used to construct a radiomics model employing various machine learning algorithms, including extremely random trees (ET), gradient boosting decision trees (GBDT), random forest (RF), and support vector machine (SVM). The optimal model was selected and combined with RLN short-axis diameter to develop a combined model. The efficacy of each model in predicting RLN metastasis was evaluated using the receiver operating characteristic (ROC) curve. Results:The volume fraction of hyper-enhanced hyper-intense regions in the non-metastatic group was significantly higher than that in the metastatic group (0.05±0.09 vs. 0.02±0.03; t=3.00, P=0.003). Among the machine learning models constructed using 15 optimal habitat radiomics features, the SVM model demonstrated the best performance, with area under the ROC curve (AUC) values of 0.85 (95% CI 0.72-0.98) in the internal test set and 0.82 (95% CI 0.67-0.98) in the external test set, surpassing those of the ET, GBDT, and RF models. The combined model, integrating the SVM model with RLN short-axis diameter, achieved AUC values of 0.94 (95% CI 0.85-1.00) in the internal test set and 0.89 (95% CI 0.78-1.00) in the external test set, with RLN short-axis diameter contributing AUC values of 0.81 (95% CI 0.66-0.96) and 0.81 (95% CI 0.68-0.94), respectively. The diagnostic sensitivity of the combined model was 91.7% in the internal test set and 85.7% in the external test set, with specificities of 78.3% and 67.7%, respectively. Conclusion:The combined model based on MRI habitat imaging radiomics and RLN short-axis diameter demonstrates excellent preoperative assessment capability for RLN metastasis in RCC.

To investigate the value of MRI for the diagnosis of achilles tendon closed rupture. 1.5T Maestro Class MRI scanner was used for the conventional scanning of 15 patients confirmed with achilles tendon closed ruptures by operation, and then the findings by imaging were compared with those by operation. The 15 patients proved with achilles tendon closed rupture, including 4 cases of incomplete rupture and 11 cases of complete rupture. MRI could display clearly the changes in morphology and signal of incomplete or complete closed ruptures of Achilles tendon, and the results were consistent with those by operation. MRI can make an accurate display of the lo-cation and extent of achilles tendon rupture.

Objective To explore the advantages of Argus method by comparing the accuracy and timeliness of Argus and artificial methods for measuring femoral head necrosis area in MRI scanning.Methods Totally 17 patients (31 hips) were measured with Argus and artificial methods respectively for the necrosis area, and then the measuring results and time were compared, and the correlation was investigated between the results and the patients' pain degree, along with that between the results and the extent of femoral head collapse.Results The necrosis area ratios determined by Argus and artificial methods were (33.5±4.08)%and (34.6±4.06)%respectively, with no statistical difference between the ratios (P>0.05). The time consumed by artificial method was (21.3 ±3.62)min, significantly longer than (7.89 ±1.03)min by Argus method, with P<0.001. Regression analysis proved that the necrosis areas were positively correlated with the patients' pain degree, and the correlation coefficient by Argus method was 0.807 8, more than 0.740 9 by artificial method. The femoral heads of 11 cases(16 hips) collapsed in the follow-up period, the necrosis areas were positively correlated with the patients collapse level, but the correlation coefficient by Argus method was 0.783 8, more than 0.726 7 by artificial method.Conclusion Argus method gains high accuracy and timeliness when used in MRI scanning of femoral head necrosis area, and thus is worth popularizing clinically.