Considering the problems such as reposition limited, easily detached and singly fired of the existing clip products, we developed an endoscopic multiple-clip applier which can apply 4 clips fired successively at a time. Th instrument also equipped with an independent grasper which can be used to clamp target tissues. In order to explor its feasibility and effectiveness of endoluminal closure of gastric perforation, 22 pig stomachs were making a 1 cm full-thickness incision from outside and closed by multiple-clip applier (n = 12) in vitro. Outcome was measured by bursting pressure and compared with negative control (n = 5) and hand suture (n = 5). We set a threshold pressure value (10 mm Hg) for a secure closure. Except 2 cases of invalid data, the mean bursting pressures of negative control, multiple-clip applier, hand suture were (1.5 ± 0.3) mm Hg, (46.0 ± 7.1) mm Hg, and (72.5 ± 7.7) mm Hg, respectively. The results showed that bursting pressure of multiple-clip applier was significantly higher than that of negative control (P < 0.05) and threshold value. Multiple-clip applier can be served as an effective and safe device to perform the endoluminal closure of gastric perforation.
Animals ; Endoscopy ; Equipment Design ; Stomach Diseases ; surgery ; Surgical Instruments ; Swine

Objective:To design Disinfection device of Infant incubator to address the existing infant incubator terminally sterilized in the presence of ultraviolet light disinfectant wipe and disinfection effect is not complete. Methods:Using vaporized hydrogen peroxide to kill spores of principle, to design a PLC and touch screen technologies such as infant incubator terminal disinfection device, mainly by vaporized hydrogen peroxide generator to accommodate infant incubator stainless steel tanks, gas communication piping, etc., through clean and dry after the infant incubator, pushed into stainless steel tanks, a key parameter set to start after the end of the introduction of the incubator to disinfection, disinfection by chemical and biological indicator discoloration indicator kill situation to judge. Results:The disinfection device for gas distribution, no disinfection dead, low-temperature sterilization effect is good and easy to verify, infant incubator for material compatibility, safe, reliable, easy to operate, chemical indicator from green to yellow, biological indicator Bacillus stearothermophilus cultured for 7 days, sterile growth. Conclusion:The device is easy to verify the sterilization effect, material compatibility, safety and reliability, reduce labor intensity in clinical neonatology and critical sections infant incubator terminal disinfection areas have higher promotion and application value.

Objective To investigate the value of improving the prediction accuracy of near-term risk for developing breast cancer by transforming the original mammography image and fusing the different types of image features using the algorithm of machine learning.Methods The craniocaudal (CC) full-field digital mammography (FFDM) of 185 women were downloaded from the clinical database at the university of Pittsburgh medical center.Firstly,the original gray images were segmented and transformed into virtual optical density images.Then the asymmetry features were separately extracted from original gray images and virtual optical density images.Two decision tree classifiers of the first stage were trained based on the features extracted from two types of image.And the scores output from the two classifiers were used as input to train the second stage of one decision tree classifier.Leave-one-case-out method was used to validate the prediction performance of near-term risk of breast cancer.Results Using two-stage decision tree fusion method to predict breast cancer,the area under the ROC curve (AUC) was 0.9612±0.0132.And the sensitivity,specificity and prediction accuracy were 96.63％(86/89),91.67％(88/96) and 94.05％(174/185).Conclusion The features extracted from virtual optical density image have higher discriminatory power of predicting breast cancer.Fusing the two kinds of image features twice by two-stage decision tree method can help to improve the prediction accuracy of near-term risk of breast cancer.

Accurate measurements of voltage and current from electrosurgery are the basis of development of electrosurgery with feedback function. We, therefore, developed a parameter measurement system based on PC, with high voltage and current from electrosurgery being sensed with transformers, amplified, filtered, transformed into single-ended signals, and then into RMS signals. The root mean square (RMS) signals were transformed into digital signals through DAQ card and the data was processed in PC with Labview. The process included sampling, displaying and storage. The experiment results indicated that the measurement system could measure the output parameters from electrosurgery steadily and correctly so that the development of the system has been successful. It can be the basis of development of embedded parameters measurement system and can provide accurate feedback information for intellectual electrosurgery.
Electrosurgery ; instrumentation ; Equipment Design

Objective To verify the feasibility of eryoablation on rabbit brain tumor under interventional MRI guidance.Methods The procedures were performed under general anaesthesia.Twenty-two New Zealand white rabbit'S brains were inoculated with VX,tumor tissue through cranial holes. MR-guided cryoablation were conducted as preliminary experiment when diameter of brain tumor grew up to 0.8 cm in size.Cryoablation lasted two cycles of 5 minutes freezing, in 2 rabbits.and of 10 minutes freezing in another 2 rabbits.After procedure and MR scanning.rabbits were executed.Specimens of rabbit'S brain showed complete necrosis pathologically after cryoablation of cycles of 10 minutes freezing.The optimal parameters of eryoablation were defined.Except for the two rabbits that died of infection,the other 16 rabbits were divided into control group and therapeutic group.According to the optimal parameters of cryoablation,cryoablation of 10 minutes freezing were performed for rabbit brain tumors in therapeutic group.Venous injeetion of 20%mannitol and subcutaneous injection of dexamethasone were used for dehydration.None of rabbit brain tumors in the control group were treated.After cryoablation,MRI scanning Was performed immediately,7 days later,14 days later and 60 days later,to observe the ablative area and the pathologic changes.The survival time wag recorded.Resuits Brain tumors could be found in all New Zealand white rabbits after inoculation except two died of inflammation.The maximum diameter of brain tumors Was from 0.7 to 1.0 elEL The tumors showed slight low signal on T1WI and slight high signal on T2WI as well as comrast enhancement after injection of Gd-DTPA.Pathologically coagulative necrosis were observed after cryoablation immediately,7 days and 14 days later,and liquefactive necrosis was found 60 days later.The correlation between MRI and pathologic appearance of tmnors are consistent.The therapeutic area ranged from 1.0 to 1.5 em.,The maximium diameter of ice ball ranged from 1.5 to 2.0 cm Conclusion CiToablation for brain tumor iS a safe and feasible therapy.

BACKGROUND:With the development of medical instruments, more and more traditional surgical operations are replaced by minimal y invasive surgeries. In minimal y invasive surgery, cutting and sealing tissue is a conventional procedure;however, due to the limitation of space and vision, the ordinary methods are not suitable for minimal y invasive surgery. OBJECTIVE:To develop high frequency electrosurgical generator that has a constant power output and ability for tissue cutting and closing. METHODS:In order to improve the efficiency of tissue cutting and sealing in surgical, a kind of high-frequency energy generator was developed for tissue cutting and sealing. The instrument consisted of switching power supply with adjustable amplitude, high-frequency power amplifier, impedance monitor and microcontrol er. The energy converter composed of switching power supply and high-frequency power amplifier converted the 220 V, 50 Hz utility powers to a kind of high-frequency energy with 450 kHz and applied on tissues. Impedance monitor would real-timely detect the electrical parameter impacting on tissue that was provide the amount of feedback to microcontrol er in order to complete constant power control and bioimpedance determination by the control er. RESULTS AND CONCLUSION:The experimental results indicated that the instrument could rapidly and stably provide high-frequency energy, and could detect the biological impedance in real-time, achieve constant power output through feedback control, and could cut and close the biological tissue efficiently.

Haptic feedback plays a significant role in minimally invasive robotic surgery (MIRS). A major deficiency of the current MIRS is the lack of haptic perception for the surgeon, including the commercially available robot da Vinci surgical system. In this paper, a dynamics model of a haptic robot is established based on Newton-Euler method. Because it took some period of time in exact dynamics solution, we used a digital PID arithmetic dependent on robot dynamics to ensure real-time bilateral control, and it could improve tracking precision and real-time control efficiency. To prove the proposed method, an experimental system in which two Novint Falcon haptic devices acting as master-slave system has been developed. Simulations and experiments showed proposed methods could give instrument force feedbacks to operator, and bilateral control strategy is an effective method to master-slave MIRS. The proposed methods could be used to tele-robotic system.
Feedback ; Humans ; Minimally Invasive Surgical Procedures ; instrumentation ; Robotics ; instrumentation ; Surgery, Computer-Assisted ; instrumentation ; Touch Perception

Objective To explore the value of MR imaging-guided percutaneous lumbar discectomy and discolysis with oxygen-ozone mixture for treatment of posterolateral lumbar disc herniation via a new puncture approach of facet joint medial route. Methods All 114 lumbar intervertebral discs in 103 patients were diagnosed as posterolateral lumber disc herniation by CT or MRI, which were located at the levels of L3-4 in 5 cases, LA-5 in 87 cases and L5-S1 in 22 cases. The procedure was guided under 0. 23 T open magnetic resonance with iPath 200 optical tracking system. A 14 G MR-compatible needle was punctured into the disc center via a new puncture approach of facet joint medial route. The therapy steps were as follows: firstly, cut nucleus pulposus and inject 6 ml oxygen-ozone mixture of 60 μg/ml in the disc center;secondly, retreat the needle to the local prominence, cut prominent part and inject 6 ml oxygen-ozone mixture of 60 μg/ml. Thirdly, retreat the needle to the periradicular nerve root, inject 15 ml oxygen-ozone mixture of 40 μg/ml and 4 ml pain-block liquid. All patients were followed up at 3 days, 1 month, 3 months and 6 months after operation, evaluated for the effect of treatment with the modified Macnab criteria, and the results were compared with the χ2 test. Results All procedures were successfully performed. Intraoperative dural injury occurred in 5 cases. Postoperative infection of intervertebral space occurred in 2 cases. The clinical effective rate was 96. 1% (99/103), 84.5% (87/103), 94.2% (97/103), 95.1% (98/103)respectively at 3 days, 1 month, 3 months and 6 months after operation, and the differences were signifieant (χ2 = 12. 942, P = 0. 005 ) . Conclusion MR imaging-guided percutaneous lumbar discectomy and discolysis with oxygen-ozone mixture via facet joint medial route is a minimally invasive, safety and effective method for the treatment of posterolateral lumbar disc herniation.

Objective To explore the value of MR imaging-guided percutaneous cervical discectomy and discolysis with oxygen-ozone mixture for treatment of cervical disc herniation.Methods Eight herniated cervical discs in 7 patients were diagnosed by MRI, including 5 discs of lateral protruding type, 2 discs of paramedian protruding type and one disc of central protruding type.All patients underwent MR imaging-guided percutaneous cervical discectomy and discolysis with oxygen-ozone mixture.The procedures were guided by a set of 0.23 T open MR system mounted with iPath 200 optical tracking system.The herniated portion of the disc was punctured with a 14 G MR-compatible needle in the healthy side via anterolateral oblique route.The interventional steps were as follows; firstly, cut herniated part with percutaneous discectomy probe and inject 2ml oxygen-ozone mixture of 60 μg/ml; secondly, retreat the needle to the disc center, resect nucleus pulposus, and inject 2 ml oxygen-ozone mixture of 60 μg/ml.All patients were followed up for 6 months, with 4 patients by telephone and 3 patients in outpatient clinic.The effect of treatment was evaluated according to Williams postoperative assessment standard.Results All procedures were performed successfully.The clinical outcome was evaluated as excellent in 5 cases, good in 1 case and fair in 1 case.The total ratio of excellent and good was 85.7%.No serious complication occurred expect 1 case with intraoperative paroxysmal pain.Conclusion MR imaging-guided percutaneous cervical discectomy and discolysis with oxygen-ozone mixture was a safe, effective and minimally invasive method for the treatment of cervical disc herniation.

Objective:To perform 3D modeling based on CT images of human stomach-esophagus structure and provide 3D models of normal and reflux forms of gastroesophagus.Methods:Based on CT images of stomach-esophagus structure, 3D models was established using Mimics 10.01, Geomagic Studio 2012 and SolidWorks 2018 software. In the modeling process, the Mimics software was used to coarsely and finely divide the model to export stomach-esophageal point cloud data. On the basis of the point cloud data, Geomagic Studio software was used to simplify and repair the model, and complete the operations of filling holes and smooth surfaces. SolidWorks software was used to process the structure of the cardia and establish a normal model of stomach-esophagus and a model of cardiac disease. Finally, the model was replicated using soft 3D printing technology.Results:The geometric parameters of the established stomach-esophagus model were within the actual range, which proved that the model has certain practicality.Conclusions:The model can be used as a basic material for gastric surgery simulation training, to help doctors or medical students to be proficient and improve the operation skills and surgical level of gastric surgery.