Successful Treatment for Hepatic Encephalopathy Aggravated by Portal Vein Thrombosis with Balloon-Occluded Retrograde Transvenous Obliteration

This report presents the case of a 78-year-old female with hepatic encephalopathy due to an inferior mesenteric venous-inferior vena cava shunt. She developed hepatocellular carcinoma affected by hepatitis C virus-related cirrhosis and underwent posterior sectionectomy. Portal vein thrombosis developed and the portal trunk was narrowed after hepatectomy. Portal vein thrombosis resulted in high portal pressure and increased blood flow in an inferior mesenteric venous-inferior vena cava shunt, and hepatic encephalopathy with hyperammonemia was aggravated. The hepatic encephalopathy aggravated by portal vein thrombosis was successfully treated by balloon-occluded retrograde transvenous obliteration via a right transjugular venous approach without the development of other collateral vessels

Treatment results of two-stage operation for the patients with esophageal cancer concomitant with liver dysfunction

Purpose : The aim of this study was to clarify the usefulness of two-stage operation for the patients with esophageal cancer who have liver dysfunction. Methods : Eight patients with esophageal cancer concomitant with liver dysfunction who underwent two-stage operation were analyzed. The patients initially underwent an esophagectomy, a cervical esophagostomy and a tube jejunostomy, and reconstruction with gastric tube was performed after the recovery of patients’ condition. Results : The average time of the 1st and 2nd stage operation was 410.0 min and 438.9 min, respectively. The average amount of blood loss in the 1st and 2nd stage operation was 433.5 ml and 1556.8 ml, respectively. The average duration between the operations was 29.8 days. The antesternal route was selected for 5 patients (62.5%) and the retrosternal route was for 3 patients (37.5%). In the 1st stage operation, no postoperative complications were observed, while, complications developed in 5 (62.5%) patients, including 4 anastomotic leakages, after the 2nd stage operation. Pneumonia was not observed through two-stage operation. No in-hospital death was experienced. Conclusion : A two-stage operation might prevent the occurrence of critical postoperative complications for the patients with esophageal cancer concomitant with liver dysfunction

Stress Dispersion Design in Continuum Compliant Structure toward Multi-DOF Endoluminal Forceps

Gastrointestinal cancer, when detected early, is treated by accessing the lesion through the natural orifice using flexible endoscopes. However, the limited degree-of-freedom (DOF) of conventional treatment devices and the narrow surgical view through the endoscope demand advanced techniques. In contrast, multi-DOF forceps systems are an excellent alternative; however, these systems often involve high fabrication costs because they require a large number of micro-parts. To solve this problem, we designed compact multi-DOF endoluminal forceps with a monolithic structure comprising compliant hinges. To allow an efficient stress dispersion at the base end when the hinge bends, we proposed a novel design method to obtain the hinge parameters using the beam of uniform strength theory. This method does not involve a high computational cost. The results show that the improved design with a variable hinge thickness can reduce the maximum bending stress, dispersing the stress in a larger area than that of the previous design considering a constant thickness of the hinge. Moreover, the experiments conducted in a prototype confirm that the radius of the curvature was significantly improved. The proposed method could aid in designing other continuum robots relying on compliant hinges

Stress Dispersion Design in Continuum Compliant Structure toward Multi-DOF Endoluminal Forceps

Gastrointestinal cancer, when detected early, is treated by accessing the lesion through the natural orifice using flexible endoscopes. However, the limited degree-of-freedom (DOF) of conventional treatment devices and the narrow surgical view through the endoscope demand advanced techniques. In contrast, multi-DOF forceps systems are an excellent alternative; however, these systems often involve high fabrication costs because they require a large number of micro-parts. To solve this problem, we designed compact multi-DOF endoluminal forceps with a monolithic structure comprising compliant hinges. To allow an efficient stress dispersion at the base end when the hinge bends, we proposed a novel design method to obtain the hinge parameters using the beam of uniform strength theory. This method does not involve a high computational cost. The results show that the improved design with a variable hinge thickness can reduce the maximum bending stress, dispersing the stress in a larger area than that of the previous design considering a constant thickness of the hinge. Moreover, the experiments conducted in a prototype confirm that the radius of the curvature was significantly improved. The proposed method could aid in designing other continuum robots relying on compliant hinges

Noninvasive Diagnosis of the Mitochondrial Function of Doxorubicin-Induced Cardiomyopathy Using In Vivo Dynamic Nuclear Polarization–Magnetic Resonance Imaging

Doxorubicin (DOX) induces dose-dependent cardiotoxicity via oxidative stress and abnormal mitochondrial function in the myocardium. Therefore, a noninvasive in vivo imaging procedure for monitoring the redox status of the heart may aid in monitoring diseases and developing treatments. However, an appropriate technique has yet to be developed. In this study, we demonstrate a technique for detecting and visualizing the redox status of the heart using in vivo dynamic nuclear polarization–magnetic resonance imaging (DNP–MRI) with 3-carbamoyl-PROXYL (CmP) as a molecular imaging probe. Male C57BL/6N mice were administered DOX (20 mg/kg) or saline. DNP–MRI clearly showed a slower DNP signal reduction in the DOX group than in the control group. Importantly, the difference in the DNP signal reduction rate between the two groups occurred earlier than that detected by physiological examination or clinical symptoms. In an in vitro experiment, KCN (an inhibitor of complex IV in the mitochondrial electron transport chain) and DOX inhibited the electron paramagnetic resonance change in H9c2 cardiomyocytes, suggesting that the redox metabolism of CmP in the myocardium is mitochondrion-dependent. Therefore, this molecular imaging technique has the potential to monitor the dynamics of redox metabolic changes in DOX-induced cardiomyopathy and facilitate an early diagnosis of this condition

Feasibility of an AI-Based Measure of the Hand Motions of Expert and Novice Surgeons

This study investigated whether parameters derived from hand motions of expert and novice surgeons accurately and objectively reflect laparoscopic surgical skill levels using an artificial intelligence system consisting of a three-layer chaos neural network. Sixty-seven surgeons (23 experts and 44 novices) performed a laparoscopic skill assessment task while their hand motions were recorded using a magnetic tracking sensor. Eight parameters evaluated as measures of skill in a previous study were used as inputs to the neural network. Optimization of the neural network was achieved after seven trials with a training dataset of 38 surgeons, with a correct judgment ratio of 0.99. The neural network that prospectively worked with the remaining 29 surgeons had a correct judgment rate of 79% for distinguishing between expert and novice surgeons. In conclusion, our artificial intelligence system distinguished between expert and novice surgeons among surgeons with unknown skill levels

Procedural surgical skill assessment in laparoscopic training environments.

International audiencePurpose - This study aimed to identify detailed differences in laparoscopic surgical processes between expert and novice surgeons in a training environment and demonstrate that surgical process modeling can be used for such detailed analysis. Methods - Eleven expert surgeons each of whom had performed [Formula: see text] laparoscopic procedures were compared with 10 young surgeons each of whom had performed [Formula: see text] laparoscopic procedures, and five medical students. Each examinee performed a specific skill assessment task. During tasks, instrument motion was monitored using a video capture system. From the video, the corresponding workflow was recorded by labeling the surgeons' activities according to a predefined terminology. Activities represented manual work steps performed during the task, described by a combination of a verb (representing the action), a tool, and the involved structure. The results were described as the number of occurrences (times), average duration (seconds), total duration (seconds), minimal duration (seconds), maximal duration (seconds), and occupancy percentage (%). Results - The terminology for describing the processes of this task included 10 actions, six tools, four structures, and three events for each hand. There were 63 combinations of different possible activities; significant differences in 12 activities were observed between the expert and novice groups (young surgeons and medical students). The expert group performed the task with fewer occurrences and shorter duration than did the novice group in the left hand. Conclusions - We identified differences in surgical process between experts and novices in laparoscopic surgical simulation. Our proposed method would be useful for education and training in laparoscopic surgery