Objective:To establish the minimum number of negative lymph nodes (nLN) required for patients undergoing gastrectomy.Methods:This was a retrospective cohort study with inclusion criteria as follows: (1) radical gastrectomy; (2) histologically confirmed adenocarcinoma; (3) complete tumor staging information; and (4) known number of lymph nodes harvested. The exclusion criteria were: (1) other concurrent malignant tumors; (2) metastatic or recurrent gastric cancer; (3) initial surgery performed at another hospital; (4) preoperative neoadjuvant therapy; (5) distant metastasis; and (6) incomplete clinical data or follow-up information. Based on the above criteria, a total of 11 167 patients with gastric adenocarcinoma who underwent radical subtotal gastrectomy (RSG) or radical total gastrectomy (RTG) in the Department of Gastric Surgery, Fudan University Shanghai Cancer Center between January 1, 2000, and December 31, 2022, were included in the study. Among them, there were 7 596 cases in the RSG group and 3 571 cases in the RTG group. Restricted cubic spline (RCS) analysis was used to determine the ideal threshold for nLN for RSG and RTG patients. Survival analysis was conducted using Kaplan-Meier (KM) curves and log-rank tests, and propensity score matching (PSM) was utilized to balance parameters between two groups. Furthermore, subgroup analysis was conducted for RSG patients based on tumor location (upper, middle and lower) to determine the minimum number of nLN in each subgroup.Results:For patients who underwent RSG, the mean number of nLN was 21.9, with a median of 21. RCS analysis showed that more than 21 nLN was associated with better survival. Moreover, both pre- and post-PSM analysis confirmed that patients with nLN ≥21 had better survival benefits compared to those with nLN <21 (overall survival [OS]: P<0.001 before PSM, P=0.013 after PSM; disease-free survival [DFS]: P<0.001 before PSM, P=0.013 after PSM). For patients who underwent RTG, the mean number of nLN was 23.5, with a median of 22. Here RCS analysis indicated that more than 22 nLN was associated with better postoperative survival in RTG patients, and both pre- and post-PSM analysis confirmed that patients with nLN ≥22 had better survival benefits compared to those with nLN<22 (OS: P<0.001 both before and after PSM; DFS: P<0.001 both before and after PSM). Subgroup analysis showed that for RSG patients with tumor located in the upper part, having ≥17 nLN (OS: both P<0.001), and for RSG patients with tumor located in the middle and lower part, having ≥22 nLN (OS: both P<0.001), were associated with better prognoses. Conclusions:For patients who receive RSG, the minimal number of nLN is ideally ≥21 (upper ≥17, middle and lower ≥22). Similarly, for patients who receive RTG, the minimum number of nLN ideally is 22.

Objective:To establish the minimum number of negative lymph nodes (nLN) required for patients undergoing gastrectomy.Methods:This was a retrospective cohort study with inclusion criteria as follows: (1) radical gastrectomy; (2) histologically confirmed adenocarcinoma; (3) complete tumor staging information; and (4) known number of lymph nodes harvested. The exclusion criteria were: (1) other concurrent malignant tumors; (2) metastatic or recurrent gastric cancer; (3) initial surgery performed at another hospital; (4) preoperative neoadjuvant therapy; (5) distant metastasis; and (6) incomplete clinical data or follow-up information. Based on the above criteria, a total of 11 167 patients with gastric adenocarcinoma who underwent radical subtotal gastrectomy (RSG) or radical total gastrectomy (RTG) in the Department of Gastric Surgery, Fudan University Shanghai Cancer Center between January 1, 2000, and December 31, 2022, were included in the study. Among them, there were 7 596 cases in the RSG group and 3 571 cases in the RTG group. Restricted cubic spline (RCS) analysis was used to determine the ideal threshold for nLN for RSG and RTG patients. Survival analysis was conducted using Kaplan-Meier (KM) curves and log-rank tests, and propensity score matching (PSM) was utilized to balance parameters between two groups. Furthermore, subgroup analysis was conducted for RSG patients based on tumor location (upper, middle and lower) to determine the minimum number of nLN in each subgroup.Results:For patients who underwent RSG, the mean number of nLN was 21.9, with a median of 21. RCS analysis showed that more than 21 nLN was associated with better survival. Moreover, both pre- and post-PSM analysis confirmed that patients with nLN ≥21 had better survival benefits compared to those with nLN <21 (overall survival [OS]: P<0.001 before PSM, P=0.013 after PSM; disease-free survival [DFS]: P<0.001 before PSM, P=0.013 after PSM). For patients who underwent RTG, the mean number of nLN was 23.5, with a median of 22. Here RCS analysis indicated that more than 22 nLN was associated with better postoperative survival in RTG patients, and both pre- and post-PSM analysis confirmed that patients with nLN ≥22 had better survival benefits compared to those with nLN<22 (OS: P<0.001 both before and after PSM; DFS: P<0.001 both before and after PSM). Subgroup analysis showed that for RSG patients with tumor located in the upper part, having ≥17 nLN (OS: both P<0.001), and for RSG patients with tumor located in the middle and lower part, having ≥22 nLN (OS: both P<0.001), were associated with better prognoses. Conclusions:For patients who receive RSG, the minimal number of nLN is ideally ≥21 (upper ≥17, middle and lower ≥22). Similarly, for patients who receive RTG, the minimum number of nLN ideally is 22.

Objective:To investigate the clinical efficacy of trigeminal neuralgia treatment in elderly patients with percutaneous balloon compression assisted by a robotic surgical navigation and positioning planning system.Methods:Eleven elderly patients with trigeminal neuralgia admitted to the Department of Neurosurgery, Beijing Chaoyang Hospital, Capital Medical University between August 2021 and August 2022 were retrospectively analyzed.Three-dimensional time-of-flight magnetic resonance angiography, a three-dimensional fast spin-echo sequence with variable flip angles and thin-slice CT scans were performed before the procedure, and multimodal image fusion was performed by a robot workstation.The volume of Meckel's cave was calculated.Two paths were set up in the surgical planning: an actual puncture path, targeting the anterior inner quadrant of the internal foramen ovale, and a virtual path, used to plan the insertion depth of the balloon.The actual puncture path was completed under the guidance of the robotic arm adapter, and the virtual path for depth measurement was completed under lateral X-ray views of digital subtraction angiography.The balloon was placed at the predetermined depth and was inflated to form a pear shape to complete the procedure.The visual analogue scale(VAS)score was used to evaluate preoperative pain, and the Barrow Neurological Institute(BNI)facial numbness score was used to evaluate postoperative facial numbness.The patients were followed up for 1-12 months and the results were analyzed.Results:In all of the 11 patients, puncturing the foramen ovale and entry into the Meckel's cave were successfully conducted and the balloon was inflated to form a pear shape.Ten patients(90.9%)achieved complete remission immediately after the procedure, and 1 patient had delayed healing at 5 days after the procedure.There were no serious complications related to the procedure.There was no recurrence of pain during the follow-up, and the BNI numbness grading was between 2-3.The ratio between the inflated balloon volume and the preoperative volume of the Meckel's cave was approximately 1.7.Conclusions:Robot-assisted percutaneous balloon compression is safe and effective for the treatment of trigeminal neuralgia in elderly patients.

Dynamic magnetic resonance (MR) imaging has generated great research interest, because it can provide both spatial and temporal information for clinical diagnosis.However, slow imaging speed or long scanning time is still a challenge for dynamic MR imaging. Most existing methods reconstruct dynamic MR images from incomplete k-space data under the guidance of compressed sensing (CS) or lowrank theory, which suffer from long iterative reconstruction time. Recently, deep learning has shown great potential in accelerating dynamic MR. Our previous work proposed a dynamic MR imaging method with both k-space and spatial prior knowledge integrated via multi-supervised network training. Nevertheless, there was still some smoothing needed in the reconstructed images at high acceleration. In this work, we propose cascaded residual dense networks for dynamic MR imaging with edge-enhanced loss constraint, dubbed cascaded residual dense networks (CRDN).Specifically, the cascaded residual dense networks fully exploit the hierarchical features from all the convolutional layers with both local and global feature fusion.We further use the higher-degree total variation loss function, which has the edge enhancement properties, for training the networks.

Objective To investigate dynamically characteristics of apparent diffusion coefficient (ADC) of MR diffusion-weighted imaging (DWI) in the rabbit VX-2 tumor model.Methods Forty New Zealand rabbits were included in the study and forty-seven rabbit VX-2 tumor models were raised by implanting directly and intrahepatically after abdominal cavity was opened.DWI was carried out periodically and respectively on seventh,fourteenth,and twenty-first day after implantation.Part samples of VX-2 tumors were studied by pathology.The distinction of VX-2 tumors on DWI was assessed by their ADC values.The statistical significance between different time groups,different area groups,or different b-value groups was calculated using SPSS12.0 software,respectively.Results ADC values of 47 VX-2 tumors in the area of tumor periphery,tumor center,and normal parenchyma around tumor were greater when b-value was 100 s/mm2 than those when b-value was 300 s/mm2 and the distinction of VX-2 tumor ADC in the area of tumor periphery,tumor center,and normal parenchyma around tumor between different b-value groups was significant,respectively( F =17.964,P ＜0.01 ; F =13.986,P ＜0.01 ; F =128.681,P ＜0.01 ).The ADC values in the area of normal liver parenchyma around tumor were greater than those in the area of VX-2 tumor periphery and tumor center when the b-value was 100 or 300 s/mm2.When b-value was the same( 100 or 300 s/mm2),the distinction of VX-2 tumor ADC between different areas was significant( F =176.586,P ＜0.01 ; F =55.089,P ＜0.01 ).The ADC of VX-2 tumor in the area of tumor periphery and tumor center became gradually low from seventh to fourteenth or twenty-first day after implantation and the distinction of ADC between different time groups but the area same (?) was significant( b =100 s/mm2,F =48.211,P ＜0.01 ;b =300 s/mm2,F =20.955,P ＜0.01 ).There were not obvious cellular necrosis in VX-2 tumors on seventh and fourteenth day after implantation but ADC of VX-2 tumor decreased unobviously because of cellular edemata in or around tumors.There were obvious cellular necrotic areas in VX-2 tumors on the twenty-first day after implantation.ADC of viable tumor cells in VX-2 tumors were lower on DWI than that in the area of normal liver parenchyma around tumor and ADC of dead tumor cells in VX-2 tumors were unequal,including high values,equal values,and low values but they were higher than that in the area of normal liver parenchyma around tumor after dead tumor cells had been liquified or had become cystic.Conclusions ADC is able to reflect objectively the diffusion of water molecules in the tumor and to reflect indirectly the degree of the growth and liquified necrosis of a tumor.ADC has an important and potential value in monitoring dynamical tumor growth and in evaluating malignant degree and therapeutic effect.

ObjectiveTo investigate its dynamic characteristics and pathological mechanism on magnatic resonance diffusion weighted imaging (DWI) after chemoembolization in rabbit liver VX-2 tumor model.MethodsForty New Zealand rabbits were included in the study and forty-seven rabbit VX-2 tumor models were raised by implanting directly and intrahepatically after abdominal cavity was opened.Forty VX-2 tumor models from them were divided into four groups.DWI was performed periodically and respectively for each group after chemoembolization.All VX-2 tumor samples of each group were studied by pathology.The distinction of VX-2 tumors on DWI was assessed by their apparent diffusion coefficient (ADC) values.The statistical significance between different time groups,different area groups,or different b-value groups was calculated using SPSS 12.0 software.ResultsWhen b-value was 100 s/mm2,ADC values in the area of VX-2 tumor periphery,VX-2 tumor central,or normal liver parenchyma around tumor became gradually low in sixteen hours after chemoembolization,and were the lowest at sixteenth hour,and then they increased gradually from sixteenth hour to fourty-eighth hour after chemoembolization.The distinction of ADC between different time groups was significant,respectively ( F =7.325,P ＜ 0.01 ; F =2.496,P ＜ 0.05 ; F =6.856,P ＜0.01 ).Cellular edema in the area of VX-2 tumor periphery or normal liver parenchyma around tumor increased quickly in sixteen hours after chemoembolization; however,from sixteenth hour to forty-eighth hour,cellular edema in the area of normal liver parenchyma around tumor decreased gradually and that in the area of VX-2 tumor periphery decreased lightly at first and then increased continually.Cellular necrosis in the area of VX-2 tumor periphery after chemoembolization was more significant than that before chemoembolization.The areas of dead cells in VX-2 tumors manifested low signal and high ADC value while the areas of viable cells manifested high signal and low ADC value.ConclusionsDWI is able to detect and discriminate tumor necrotic areas from viable cellular areas before and after chemoembolization.ADC of normal liver parenchyma and VX-2 tumor are influenced by intracellular edema,tissue cellular death,and microcirculation disturbance after chemoembolization.

Purpose:To further improve the therapeutic results of ESWL and to reduce the complications of ESWL. Methods: Clinical materials of 5 140 cases of patients with urinary calculi underwent ESWL from 1989 to 1999 were analyzed retrospectively. Results: Ignorance of the routine examination in urine, blood, hepatic func tion and specialization etc, the serious complications may be produced by ESWL. Low energy and emergency ESWL have obtained satisfactory results. Conclusions:Every routine examination is essential to secure the patient to get satisfactory therapeutic result from ESWL and prevent the complication from occurring. Complete dis charge rate of stones was affected by the tissue structure and type of the renal pelvis and calyces, beside the site of stones.