Objective To propose an innovative self-supervised learning method for vascular segmentation in computed tomography angiography (CTA) images by integrating feature reconstruction with masked autoencoding. Methods A 3D masked autoencoder-based framework was developed, where in 3D histogram of oriented gradients (HOG) was utilized for multi-scale vascular feature extraction. During pre-training, random masking was applied to local patches of CTA images, and the model was trained to jointly reconstruct original voxels and HOG features of masked regions. The pre-trained model was further fine-tuned on two annotated datasets for clinical-level vessel segmentation. Results Evaluated on two independent datasets (30 labeled CTA images each), our method achieved superior segmentation accuracy to the supervised neural network U-Net (nnU-Net) baseline, with Dice similarity coefficients of 91.2% vs. 89.7% (aorta) and 84.8% vs. 83.2% (coronary arteries). Conclusion The proposed self-supervised model significantly reduces manual annotation costs without compromising segmentation precision, showing substantial potential for enhancing clinical workflows in vascular disease management.
Objective To explore the effect of multimodal interventions in improving the compliance rate of core infection control measures on reducing the incidence rate of vessel catheter associated infection (VCAI). Methods Inpatients with intravascular catheters in 5 departments with high rates of vascular catheterization and infection of Dongguan People’s Hospital between January 2021 and December 2022 were selected. According to the hospital stay, patients were divided into a pre-intervention group (January to December 2021) and a post-intervention group (January to December 2022). The core infection control measures assessment pass rates of medical staff between the two periods and the differences in the incidence rate of VCAI, average catheterization days, and catheterization rate before and after intervention in both groups were compared. Results A total of 8174 patients were included. Among them, there were 3915 patients in the pre-intervention group and 4259 patients in the post-intervention group. In the pre-intervention group, the total length of hospital stay was 122885 days, the total number of catheterization days was 48028 days, and 28 cases of VCAI occurred. In the post-intervention group, the total length of hospital stay was 126966 days, the total number of catheterization days was 51253 days, and 12 cases of VCAI occurred. After intervention, the compliance rate of VCAI core infection control measures was improved [69.21% (2907/4200) vs. 91.24% (3832/4200); χ2=642.090, P＜0.001], the pass rate of medical staff’s core infection control measures assessment was improved [53.33% (128/240) vs. 91.67% (220/240); χ2=88.443, P＜0.001], the catheterization rate was increased [39.08% (48028/122885) vs. 40.37% (51253/126966); χ2=42.979, P<0.001], and the incidence rate of VCAI was reduced [0.58‰ (28/48028) vs. 0.23‰ (12/51253); incidence-rate ratios =0.40, 95% confidence interval (0.20, 0.79), P=0.008]. Conclusions Improving the compliance rate of VCAI core infection control measures through multimodal interventions can significantly improve the passing rates of core infection control measures of medical staffs. This will help to reduce the incidence of VCAI and ensuring patient safety, provide evidence-based support for the prevention and control of VCAI.
To investigate the feasibility of using the pedicled patella for repaire of the superior articular surface of the medial tibial condyle, 37 lower limbs were studied by perfusion. In this series, there were 34 obsolete specimens and 3 fresh specimens of lower legs. Firstly, the vessels which supply to patella were observed by the methods of anatomy, section and casting mould. Then, the form and area of the patellar and tibial medial conylar articular surface were measured in 30 cases. The results showed: (1) the arteries supplied to patella formed a prepatellar arterial ring around patella, and the ring gave branches to patella; (2) medial inferior genicular artery and inferior patellar branches of the descending genicular arterial articular branch merge and acceed++ to prepatellar ring at inferior medial part of patella; (3) the articular surface of patella is similar to the superior articular surface of the tibial medial condyle on shape and area. It was concluded that the pedicled patella can be transposed to medial tibial condyle for repaire of the defect of the superior articular surface. The function of the knee can be reserved by this method.
OBJECTIVE: To study the clinical result of treating firearm-wound with the vessel pedicel tissue flap. METHODS: From May 1992 to October 2000, 21 cases of firearm-wound of upper limbs underwent transplantation with the vessel pedicel tissue flap. Of them, the locations of the wound were upper arm in 11 cases, forearm in 7 cases, hand in 3 cases. The size of wound was 1.0 cm x 0.5 cm to 8.0 cm x 6.5 cm; the wound course was 3 minutes to 8 hours with an average of 3 hours and 30 minutes. The patients were followed up 3 months to 2 years. RESULTS: In 21 cases, the results were excellent in 19 cases and poor in 2 cases. The good rate was 90.5%. CONCLUSION: Treatment of firearm-wound with vessel pedicel tissue flap has the good effect.
OBJECTIVE: To sum up the experience of clinical application of distal base sural island flap. METHODS: From January 1997 to April 1999, the posterior island flap of leg pedicled with sural nerve and its nutrient vessels was applied to repair heel or dorsum of foot in 6 cases, chronic ulcer of heel in 2 cases, chronic osteomyelitis in 2 cases, scar contracture of bone defect accompanying fistulation in 1 case. The range of flap was 5 cm x 8 cm to 8 cm x 12 cm. RESULTS: All the flaps survived completely without vascular crisis. All the wounds healed by first intention. Followed up 3 to 12 months, no ulcer, osteomyelitis, fistulation were recurrence, and the sensation of flap was recovered slightly. CONCLUSION: The flap do not damage critical blood vessels and nerves, the donating region is hidden. The manual of operation is simple and blood supply of flap is sufficient. It can repair the defect of soft tissue on heel and dorsum with high survival rate.
Abstract In order to have more selective sources of skin flaps to repair soft tissue defects, the prefabricated flap combining with skin expander was tried. Implanted the dorsal thoracic artery and vein with a muscle bundle of latissimus dorsi into the lateral thoracic wall subdermally andset a skin expander subcutaneously. Injected saline into the expander to inflate the flap gradually. In a month, an axial flap with the dorsal thoracic vesselswas prepared. the flap was transferred to the defect by vascular anastomosis technique. This method was applied in two cases, one to the left ankle, another to the left side of the neck. The sizes of the two flaps were 20cm×14cmand 22cm×15cm respectively. After operation, the flaps were alive completely. The advantages included selective source of vascular pedicle, thinpliable flap with enough blood supply, and direct closure of the donor site without skin graft.
rom Aug.1965 to Dec. 1992,29 patients suffered from the peudoaneurysms were treatedwlth 4 different methods. They were:1.ligating the vessels;2. repairing the defected area in thearterial watl: 3, anastomosing the vessels after the peudoaneurysms being removed; 4, repoiring thearteries with vessel grafts after the resection of the poudoaneurysm or by-passing operation. Of the 4different methed, the method 3 and 4 gave the best results. It was thought that the operation should bep...
Objective To study the clinicopathologic features which influence the prognosis of patients with stage Ib nonsmall cell lung cancer (NSCLC) after operation, and discuss the indication of postoperative chemotherapy. Methods From January 2002 to December 2002, the clinical materials of 152 patients who underwent complete pulmonary lobectomy and were confirmed to have stage Ib NSCLC by postoperative histopathological examination were collected from Shanghai Chest Hospital. There were 82 male and 70 female cases aged from 33-80 years. The mean age was 63.0 years. KaplanMeier method was used to compare and analyze the age, gender, tumor diameter, tumor location, lymphatic or vascular carcinoma embolus, differentiation, pleural invasion and chemotherapy of patients. Cox regression model was used to do prognostic multivariate analysis to above factors. Results The 5year survival rate was 71.1%. The median survival time was 44.20 months. The results of single factor analysis showed that the tumor diameter was longer than 5 cm（χ2=4.020，P=0.042）, lymphatic or vascular carcinoma embolus existed（χ2=14670，P=0.001）, poorly differentiated tumor（χ2=8.395，P=0.004）, and those whose tumors were located on middlelower lobars had a poor prognosis（χ2=3.980，P=0.045）. The age(χ2=0.478，P=0.740), gender(χ2=0.571，P=0.450), pathological type(χ2=0.406，P=0.816), pleural invasion(χ2=0.022，P=0.882) and postoperative chemotherapy of patients (χ2=1.067，P=0.302)had no relationship with postoperative survival. The results of multivariate analysis showed that lymphatic or vascular carcinoma embolus（P=0.006，95%CI:1.491,10.524） and poorly differentiated tumor（P= 0.001,95%CI:0.116,0.578） were the main factors which influenced the survival rate of patients. Conclusion The tumor differentiation and lymphatic or vessel carcinoma embolus of patients with stage Ib NSCLC are important factors which influence prognosis and survival rate. The poorly differentiated tumor and lymphatic or vessel carcinoma embolus could be regarded as one of the indications of postoperative chemotherapy.
Objective To present a method for quantifying the anastomosis between two vessels based on angiograpy and provide a theoretical basis for vascular study in skin flap. Methods Ten bilateral skin flaps of 20 cm×20 cmbased on deep iliac circumflex vessels were elevated fromthe abdominal wall including musculus rectus abdominis and deep superior epigastric vessels in 5 minipigs which were 100-115 cm in length and 25-35 kg in weight. One side was inserted an expander under the panniculus carnosus and was expanded regularly with 30-40 ml isotonic Na chloride injection (expanded group) and the other was unexpanded group which were without any treatment. A X-ray image of the flap vessles was obtained after a gelatinlead oxide mixture was carotid arterially injected and 24 hours of cryopreservation of the body. Three parallel lines with equal interval perpendicular to long axis of the two vessels were designed at the communication area. Vessel anastomosis quantifying was determined by counting the number of marks derived from the intersections of the lines and the vessels and statistical analysis was carried out. Results The mark of intersectionin expanded group (81.20±10.33) was more than that in unexpanded group (22.40±5.41), showing significant difference(Plt;0.01). Conclusion The method for quantifying vessel anastomosis in skin flap is simple, reliable, and easytoperform. The principles of this procedure may also be applied to other experimental and clinical studies.
ObjectiveTo construct the connective tissue growth factor (CTGF) recombinant interference vector (shRNA) and observe its inhibitory effect on the expression of endogenous CTGF in retinal vascular endothelial cells. Methods The human CTGF shRNA was constructed and the high-titer CTGF shRNA lentivirus particles was acquired via three-plasmid lentivirus packaging system to infect retinal vascular endothelial cells. The optimal multiplicity and onset time of lentivirus infection were identified by tracing down the red florescent protein in interference vector. The cells were classified into three groups: blank control group, infection control group and CTGF knockdown group. The differences in cells migrating ability was observed through Transwell allay. The mRNA and protein expression of CTGF, fibronectin, α-smooth muscle actin (α-SMA) and collagen Ⅰ (Col Ⅰ) were quantified through real-time PCR testing and Western blot system. Data between the three groups were examined via one-way analysis of variance. ResultsThe result showed that an optimal multiplicity of 20 and onset time of 72 hours were the requirements to optimize lentivirus infection. Transwell allay result showed a contrast in the number of migrated cells in the CTGF knockdown group and that in the blank control group and infection control group (F=20.64, P=0.002). Real-time PCR testing showed a contrast in related gene expression (CTGF, fibronectin, α-SMA and Col Ⅰ) in the CTGF knocked-down group and that in the blank control group and infection control group (F=128.83, 124.44, 144.76, 1 374.44; P=0.000, 0.000, 0.000, 0.000). Western blot system showed the statistical significance of the contrasted number of related protein expression (CTGF, fibronectin, α-SMA and Col Ⅰ) in the knockdown group and that in the blank control group (F=22.55, 41.60, 25.73, 161.68; P=0.002, 0.000, 0.001, 0.000). ConclusionThe success in producing CTGF shRNA lentivirus particle suggests that CTGF shRNA lentivirus can effectively knock down CTGF expression.