Objective To address the need for rapid review of automated organ-at-risk (OAR) contouring for head-and-neck cancer in online adaptive radiotherapy, this study used dosimetric indices as the reference standard to evaluate the suitability of geometric similarity metrics and to develop a rapid screening model that balances the risk of missed errors with review efficiency. Methods This retrospective study included 29 patients with head-and-neck radiotherapy, yielding 243 pairs of OAR contours (auto-generated vs. manual). Geometric similarity metrics, including the Dice similarity coefficient (Dice), the 95th percentile Hausdorff distance (HD95), and the maximum Hausdorff distance (HD100), were computed between the two contour sets. Using the dose distributions from clinical treatment plans, dosimetric differences between the two contour sets were calculated for key indices, including mean dose (D_mean) and maximum dose (D_max). Correlations between geometric metrics and dosimetric differences were analyzed. Dosimetric discrepancy events were defined as Y_3Gy using a threshold of 3 Gy. Within a univariable logistic regression triage framework, each geometric metric was used as an independent variable to estimate the probability of Y_3Gy. Discriminative performance was assessed using receiver operating characteristic (ROC) curves and precision-recall (PR) curves, with the area under the curve (AUC) including ROC-AUC and PR-AUC. Practical operating thresholds were determined via threshold sweeping. Results Geometric similarity metrics showed weak-to-moderate correlations with dosimetric differences; compared with maximum dose, correlations with mean dose differences were more consistent. Among the evaluated metrics, HD95 achieved the best classification performance for Y_3Gy. Threshold sweeping suggested that an HD95 threshold in the range of 4-9 mm can balance the risk of missed discrepancies with the efficiency of automated contour quality assurance (QA). Conclusion Several geometric similarity metrics demonstrated only weak-to-moderate associations with dosimetric differences. For head-and-neck OAR contour QA in this study, HD95 provided the best discriminative performance and can support rapid triage of automated contours, with a practical operating threshold range of 4-9 mm, potentially improving the efficiency of adaptive radiotherapy workflows.

Objective To address the need for rapid review of automated organ-at-risk (OAR) contouring for head-and-neck cancer in online adaptive radiotherapy, this study used dosimetric indices as the reference standard to evaluate the suitability of geometric similarity metrics and to develop a rapid screening model that balances the risk of missed errors with review efficiency. Methods This retrospective study included 29 patients with head-and-neck radiotherapy, yielding 243 pairs of OAR contours (auto-generated vs. manual). Geometric similarity metrics, including the Dice similarity coefficient (Dice), the 95th percentile Hausdorff distance (HD95), and the maximum Hausdorff distance (HD100), were computed between the two contour sets. Using the dose distributions from clinical treatment plans, dosimetric differences between the two contour sets were calculated for key indices, including mean dose (D_mean) and maximum dose (D_max). Correlations between geometric metrics and dosimetric differences were analyzed. Dosimetric discrepancy events were defined as Y_3Gy using a threshold of 3 Gy. Within a univariable logistic regression triage framework, each geometric metric was used as an independent variable to estimate the probability of Y_3Gy. Discriminative performance was assessed using receiver operating characteristic (ROC) curves and precision-recall (PR) curves, with the area under the curve (AUC) including ROC-AUC and PR-AUC. Practical operating thresholds were determined via threshold sweeping. Results Geometric similarity metrics showed weak-to-moderate correlations with dosimetric differences; compared with maximum dose, correlations with mean dose differences were more consistent. Among the evaluated metrics, HD95 achieved the best classification performance for Y_3Gy. Threshold sweeping suggested that an HD95 threshold in the range of 4-9 mm can balance the risk of missed discrepancies with the efficiency of automated contour quality assurance (QA). Conclusion Several geometric similarity metrics demonstrated only weak-to-moderate associations with dosimetric differences. For head-and-neck OAR contour QA in this study, HD95 provided the best discriminative performance and can support rapid triage of automated contours, with a practical operating threshold range of 4-9 mm, potentially improving the efficiency of adaptive radiotherapy workflows.

Objective To address the need for rapid review of automated organ-at-risk (OAR) contouring for head-and-neck cancer in online adaptive radiotherapy, this study used dosimetric indices as the reference standard to evaluate the suitability of geometric similarity metrics and to develop a rapid screening model that balances the risk of missed errors with review efficiency. Methods This retrospective study included 29 patients with head-and-neck radiotherapy, yielding 243 pairs of OAR contours (auto-generated vs. manual). Geometric similarity metrics, including the Dice similarity coefficient (Dice), the 95th percentile Hausdorff distance (HD95), and the maximum Hausdorff distance (HD100), were computed between the two contour sets. Using the dose distributions from clinical treatment plans, dosimetric differences between the two contour sets were calculated for key indices, including mean dose (D_mean) and maximum dose (D_max). Correlations between geometric metrics and dosimetric differences were analyzed. Dosimetric discrepancy events were defined as Y_3Gy using a threshold of 3 Gy. Within a univariable logistic regression triage framework, each geometric metric was used as an independent variable to estimate the probability of Y_3Gy. Discriminative performance was assessed using receiver operating characteristic (ROC) curves and precision-recall (PR) curves, with the area under the curve (AUC) including ROC-AUC and PR-AUC. Practical operating thresholds were determined via threshold sweeping. Results Geometric similarity metrics showed weak-to-moderate correlations with dosimetric differences; compared with maximum dose, correlations with mean dose differences were more consistent. Among the evaluated metrics, HD95 achieved the best classification performance for Y_3Gy. Threshold sweeping suggested that an HD95 threshold in the range of 4-9 mm can balance the risk of missed discrepancies with the efficiency of automated contour quality assurance (QA). Conclusion Several geometric similarity metrics demonstrated only weak-to-moderate associations with dosimetric differences. For head-and-neck OAR contour QA in this study, HD95 provided the best discriminative performance and can support rapid triage of automated contours, with a practical operating threshold range of 4-9 mm, potentially improving the efficiency of adaptive radiotherapy workflows.

Objective To explore the technical process and clinical application of laparoscopic combined upper midline incision minimally invasive liver transplantation. Methods A retrospective analysis was conducted on 30 cases of laparoscopic combined upper midline incision minimally invasive liver transplantation. The cases were divided into cirrhosis group (15 cases) and liver failure group (15 cases) based on the primary disease. The surgical and postoperative conditions of the two groups were compared. Results All patients successfully underwent laparoscopic "clockwise" liver resection, with no cases of passive conversion to open surgery or intolerance to pneumoperitoneum. In 6 cases, the right lobe was relatively large, and the right hepatic ligaments could not be completely mobilized. One case required an additional reverse "L" incision during open surgery. All patients successfully completed the liver transplantation, with no major intraoperative bleeding, cardiovascular events, or other occurrences in the 30 patients. The model for end-stage liver disease (MELD) score in the cirrhosis group was lower than that in the liver failure group (P<0.001). There were no statistically significant differences between the two groups in terms of age, surgical time, blood loss, anhepatic phase, or cold ischemia time (all P>0.05). During the perioperative period, there was 1 case of hepatic artery embolism, 1 case of portal vein anastomotic stenosis, no complications of hepatic vein and inferior vena cava, and 3 cases of biliary anastomotic stenosis, all of which occurred in the liver failure group. Conclusions In strictly selected cases, the minimally invasive liver transplantation technique combining laparoscopic hepatectomy with upper midline incision for graft implantation has the advantages of smaller incisions, less bleeding, relatively easier operation, and faster postoperative recovery, which is worthy of clinical promotion and application.

Objective To explore the feasibility and clinical experience of the middle hepatic vein splitting-reconstruction technique in split liver transplantation from low-age donor livers. Methods A retrospective analysis was conducted on the cases of two low-age donor livers that underwent middle hepatic vein splitting-reconstruction, which were transplanted into four child recipients at the Liver Transplantation Center of the Third Affiliated Hospital of Sun Yat-sen University from January 2017 to July 2023. The surgical and postoperative conditions were summarized and analyzed. Results Donor 1 was a 6-year-old and 4-month-old girl with a body weight of 21 kg, and the obtained donor liver weighed 496 g. After splitting, the left and right liver weights were 201 g and 280 g, and transplanted into a 9-month-old boy weighing 6.5 kg and a 9-month-old boy weighing 7.5 kg, respectively. The graft to recipient weight ratio (GRWR) was 3.09% and 3.73%, respectively. Donor 2 was a 5-year-old and 8-month-old boy with a body weight of 19 kg, and the donor liver weighed 673 g. After splitting, the left and right liver weights were 230 g and 400 g, and transplanted into a 13-month-old girl weighing 9.5 kg and a 15-month-old boy weighing 12 kg. The GRWR was 2.42% and 3.33%, respectively. Both donor livers were split ex vivo, with the middle hepatic vein being completely split in the middle and reconstructed using allogeneic iliac vein and iliac artery vascular patches. According to GRWR, none of the 4 transplant livers were reduced in volume. Among the 4 recipients, one died due to postoperative portal vein thrombosis and non-function of the transplant liver, while the other three cases recovered smoothly without early or late complications. Regular follow-up was conducted until July 31, 2023, and liver function recovered well. Conclusions Under the premise of detailed assessment of the donor liver and meticulous intraoperative operation, as well as matching with suitable child recipients, low-age donor livers may be selected for splitting. The complete splitting and reconstruction of the middle hepatic vein in the middle may effectively ensure the adequate venous return of the left and right liver and provide sufficient functional liver volume.

Objective To quantitatively compare the dosimetric differences among 4 volumetric modulated arc therapy(VMAT)plans by analyzing the number of arcs and collimator angle settings,aiming to establish a standardized planning template for hippocampal-sparing prophylactic cranial irradiation(HS-PCI)in clinic and improve both planning quality and clinical efficiency.Methods Twenty HS-PCI patients were enrolled,with 4 VMAT plans(V2c,V2p,V3,and V4)for each patient.The differences in target dose,organs-at-risk dose,and monitor units were compared.Results V4 plan had the highest PTV D98%and V95%,and the differences of PTV D98%in V2c vs V2p,V2c vs V4,and PTV V95%in V2c vs V4 were statistically significant(P<0.05).Meanwhile,V4 plan had the lowest PTV Dmax and Dmin doses.Specifically,statistically significant differences were observed in PTV Dmax in V4 vs V2c,V4 vs V2p,V4 vs V3,as well as PTV Dmin in V2c vs V2p,V2c vs V3,V2c vs V4,V2p vs V4(P<0.05).The PTV Dmean was the highest in V2p plan,with statistically significant differences observed in V2c vs V2p,V2c vs V4,V2p vs V3,and V3 vs V4(P<0.05).The highest PTV D2%dose was observed in V2p plan,and the differences in V2c vs V2p,V2c vs V4,V2p vs V3,V3 vs V4 were statistically significant(P<0.05).The homogeneity index and conformity index were close in 4 plans(P=0.946,P=0.380).V4 plan had the lowest Dmax,Dmean,and Dmin of the hippocampus,with significant differences in hippocampal Dmax in V4 vs V2c,V4 vs V2p,hippocampal Dmean in V4 vs V2c,V4 vs V2p,V3 vs V2c,and hippocampal Dmin in V2c vs V2p/V3/V4,and V4 vs V2p(P<0.05).V3 plan had the lowest Dmax for bilateral lenses,and V4 plan showed the lowest Dmax for lenses with a 3 mm expansion,with significant differences between V2c and V2p/V3/V4(P<0.05).V4 plan had the lowest dose for the right optic nerve,with significant differences in V4 vs V2p,and V4 vs V3(P<0.05).No significant differences were observed for the left optic nerve and optic chiasm.The monitor units in V2p plan was the lowest.Conclusion When differences in organs-at-risk doses and plan quality parameters are insignificant,V2p plan is recommended as it can ensure treatment quality while reducing delivery time.

Objective To evaluate the accuracy of multiparametric imaging on the dual-source CT through acceptance and commissioning testing, and to provide a reference for standardized clinical application. Methods Both the adult and pediatric dual-source CT scanning modes were used to scan the electron density phantom, and identical multiparametric image reconstruction tasks were performed, including the conventional CT images, the mixed CT images, the virtual monoenergetic images, the iodine images, the electron density images, and the effective atomic number images. Results In the adult scanning mode, the virtual monoenergetic CT numbers showed the greatest difference for the cortical bone (1722 HU at 40 keV vs. 30 HU at 80 keV), with smaller differences observed for other materials as their atomic numbers decreased. The pediatric scanning mode exhibited a similar trend, with the largest difference occurring at 40 keV (1393 HU). In the adult scanning mode, the deviations between the theoretical and measured iodine concentration values were all within 5%, whereas in the pediatric scanning mode, the largest deviation was 15% for an iodine concentration of 2.0 mg/mL. For the electron density, the largest deviation between the theoretical and measured values occurred in the LN450 lung (9.18% in the adult scanning mode and 8.96% in the pediatric scanning mode); the deviations for the LN300 lung were all below 7.2%, for aluminum below 6.3%, and for other tissues within 3%. For the effective atomic number, the deviations between the theoretical and measured values were all within 5% in both scanning modes. Conclusion To ensure the accuracy and reproducibility of the dual-source CT applications, a comprehensive acceptance testing protocol should be established to guarantee the safety and precision of the CT localization process.

Objective To quantitatively compare the dosimetric differences among 4 volumetric modulated arc therapy(VMAT)plans by analyzing the number of arcs and collimator angle settings,aiming to establish a standardized planning template for hippocampal-sparing prophylactic cranial irradiation(HS-PCI)in clinic and improve both planning quality and clinical efficiency.Methods Twenty HS-PCI patients were enrolled,with 4 VMAT plans(V2c,V2p,V3,and V4)for each patient.The differences in target dose,organs-at-risk dose,and monitor units were compared.Results V4 plan had the highest PTV D98%and V95%,and the differences of PTV D98%in V2c vs V2p,V2c vs V4,and PTV V95%in V2c vs V4 were statistically significant(P<0.05).Meanwhile,V4 plan had the lowest PTV Dmax and Dmin doses.Specifically,statistically significant differences were observed in PTV Dmax in V4 vs V2c,V4 vs V2p,V4 vs V3,as well as PTV Dmin in V2c vs V2p,V2c vs V3,V2c vs V4,V2p vs V4(P<0.05).The PTV Dmean was the highest in V2p plan,with statistically significant differences observed in V2c vs V2p,V2c vs V4,V2p vs V3,and V3 vs V4(P<0.05).The highest PTV D2%dose was observed in V2p plan,and the differences in V2c vs V2p,V2c vs V4,V2p vs V3,V3 vs V4 were statistically significant(P<0.05).The homogeneity index and conformity index were close in 4 plans(P=0.946,P=0.380).V4 plan had the lowest Dmax,Dmean,and Dmin of the hippocampus,with significant differences in hippocampal Dmax in V4 vs V2c,V4 vs V2p,hippocampal Dmean in V4 vs V2c,V4 vs V2p,V3 vs V2c,and hippocampal Dmin in V2c vs V2p/V3/V4,and V4 vs V2p(P<0.05).V3 plan had the lowest Dmax for bilateral lenses,and V4 plan showed the lowest Dmax for lenses with a 3 mm expansion,with significant differences between V2c and V2p/V3/V4(P<0.05).V4 plan had the lowest dose for the right optic nerve,with significant differences in V4 vs V2p,and V4 vs V3(P<0.05).No significant differences were observed for the left optic nerve and optic chiasm.The monitor units in V2p plan was the lowest.Conclusion When differences in organs-at-risk doses and plan quality parameters are insignificant,V2p plan is recommended as it can ensure treatment quality while reducing delivery time.

Objective To investigate the diagnosis and treatment strategy of the portal vein complications in children undergoing split liver transplantation. Methods The clinical data of 88 pediatric recipients who underwent split liver transplantation were retrospectively analyzed. Intraoperative anastomosis at the bifurcating site of the portal vein or donor iliac vein bypass anastomosis was performed depending on the internal diameter and development of the recipient's portal vein. A normalized portal venous blood stream monitoring was performed during the perioperative stage. After operation, heparin sodium was used to bridge warfarin for anticoagulation therapy. After portal vein stenosis or thrombosis was identified with enhanced CT or portography, managements including embolectomy, systemic anticoagulation, interventional thrombus removal, balloon dilatation and/or stenting were performed. Results Among the 88 recipients, a total of 10 children were diagnosed with portal vein complications, of which 4 cases were diagnosed with portal vein stenosis at 1 d, 2 months, 8 months, and 11 months after surgery, and 6 cases were diagnosed with portal vein thrombosis at intraoperative, 2 d, 3 d (n=2), 6 d, and 11 months after surgery, respectively. One patient with portal vein stenosis and one patient with portal vein thrombosis died perioperatively. The fatality related to portal vein complications was 2% (2/88). Of the remaining 8 patients, 1 underwent systemic anticoagulation, 2 underwent portal venous embolectomy, 1 underwent interventional balloon dilatation, and 4 underwent interventional balloon dilatation plus stenting. No portal venous related symptoms were detected during postoperative long term follow up, and the retested portal venous blood stream parameters were normal. Conclusions The normalized intra- and post-operative portal venous blood stream monitoring is a useful tool for the early detection of portal vein complications, the early utilization of useful managements such as intraoperative portal venous embolectomy, interventional balloon dilatation and stenting may effectively treat the portal vein complications, thus minimizing the portal vein complication related graft loss and recipient death.

Objective:To investigate the anatomic classification and reconstruction of right intrahepatic bile duct in the donor liver of split liver transplantation (SLT).Methods:The retrospective and descriptive study was constructed. The clinical data of 85 patients who underwent SLT in the Third Affiliated Hospital of Sun Yat-sen University from July 2014 to January 2022 were collected. There were 65 males and 20 females, aged 45(range, 1-82)years. Observation indicators: (1) surgical conditions; (2) anatomy of right intrahepatic bile duct; (3) bile duct reconstruction; (4) postoperative biliary complications; (5) follow-up. Measurement data with normal distribution were represented as Mean± SD, and measurement data with skewed distribution were represented as M(range) or M( Q1, Q3).Count data were described as absolute numbers or percentages, and comparison between groups was conducted using the chi-square test or Fisher exact probability. Results:(1) Surgical conditions. Of the 85 donor livers, 11 donor livers were split between the left and right hemilivers, and 74 donor livers were split between the classic right trilobe and left lateral lobe. The cold ischemia time of 85 donor livers was 291(273, 354)minutes, and the operation time, anhepatic phase time and volume of intraoperative blood transfusion of 85 recipients were (497±97)minutes, 51(40, 80)minutes and 8(7, 12)U. (2) Anatomy of right intrahepatic bile duct. Of the 85 donor livers, there were 47 donor livers with classic bile duct anatomical model (type 1), of the ratio as 55.3%(47/85), and 38 donor livers with anatomical variants, of the ratio as 44.7%(38/85). Of the 38 donor livers with anatomical variants, 7 donor livers were type 2, 16 donor livers were type 3a, 2 donor livers were type 3b, 2 donor livers were type 3c, 1 donor liver was type 4, 3 donor livers were type 5a, 4 donor livers were type 5b, 3 donor livers were type 6. For bile duct splitting patterns of the 85 donor livers, 84 donor livers were split with the main trunk of common hepatic duct preserving in the right hemiliver or right trilobe, and 1 donor liver were treated with complete left and right hemiliver splitting to preserve the main trunk of the common hepatic duct in the left hemiliver and the right hemiliver in the right hepatic duct (type 1 bile duct anatomical model). There were 84 donor livers with only one bile duct opening, and 1 donor liver with two bile duct openings (type 3c bile duct anatomical model). (3) Bile duct reconstruction. Of the 85 recipients, there were 69 recipients with common bile duct end-to-end anastomosis to common bile duct of donor liver (38 donor livers with type 1 bile duct anatomical model, 5 donor livers with type 2 bile duct anatomical model, 14 donor livers with type 3a bile duct anatomical model, 2 donor livers with type 3b bile duct anatomical model, 1 donor liver with type 4 bile duct anatomical model, 3 donor livers with type 5a bile duct anatomical model, 4 donor livers with type 5b bile duct anatomical model, 2 donor livers with type 6 bile duct anatomical model), 11 recipients with jejunum anastomosis to common bile duct of donor liver (7 donor livers with type 1 bile duct anatomical model, 2 donor livers with type 2 bile duct anatomical model, 1 donor liver with type 3c bile duct anatomical model, 1 donor liver with type 6 bile duct anatomical model), 3 recipients with jejunum anastomosis to common hepatic duct of donor liver (1 donor liver with type 1 bile duct anatomical model, 2 donor livers with type 3a bile duct anatomical model), 1 recipient with jejunum anastomosis to right hepatic duct of donor liver (type 1 bile duct anatomical model), 1 recipient with common hepatic duct end-to-end anastomosis to right posterior branch of donor liver combined with jejunum of the recipient Roux-en-y anastomosis to common hepatic duct of donor liver (type 3c bile duct anatomical model). (4) Postoperative biliary complications. Of the 85 recipients, 6 cases had postoperative biliary complications, with an incidence of 7.1% (6/85). Of the 6 recipients with postoperative biliary complications, there were 5 recipients with donor liver with type 1 bile duct anatomical model, including 3 cases undergoing postoperative biliary stricture with biliary leakage and 2 cases undergoing postoperative biliary anastomotic stricture, 1 recipient with donor liver with type 3b bile duct anatomical model and undergoing postoperative biliary anastomotic stricture and bile leakage in the liver section. Cases with biliary complications were 5 in the 47 recipients with donor liver with classic bile duct anatomical model and 1 in the 38 recipients with donor liver with anato-mical variants, showing no significant difference between them ( P>0.05). (5) Follow-up. There were 83 recipients receiving followed up for 52(12,96)months. During the follow-up period, 2 recipients died due to non-biliary complication factors (1 donor liver with type 1 bile duct anatomical model and 1 donor liver with 3a bile duct anatomical model). Conclusion:The anatomical classification of right intrahepatic bile duct of donor liver in SLT is mainly classical bile duct anatomical model, and the bile duct reconstruction scheme is mainly common bile duct of donor liver end-to-end anasto-mosis to common bile duct of recipient.