Depth Image-Based Deep Learning of Grasp Planning for Textureless Planar-Faced Objects in Vision-Guided Robotic Bin-Picking.

Bin-picking of small parcels and other textureless planar-faced objects is a common task at warehouses. A general color image-based vision-guided robot picking system requires feature extraction and goal image preparation of various objects. However, feature extraction for goal image matching is difficult for textureless objects. Further, prior preparation of huge numbers of goal images is impractical at a warehouse. In this paper, we propose a novel depth image-based vision-guided robot bin-picking system for textureless planar-faced objects. Our method uses a deep convolutional neural network (DCNN) model that is trained on 15,000 annotated depth images synthetically generated in a physics simulator to directly predict grasp points without object segmentation. Unlike previous studies that predicted grasp points for a robot suction hand with only one vacuum cup, our DCNN also predicts optimal grasp patterns for a hand with two vacuum cups (left cup on, right cup on, or both cups on). Further, we propose a surface feature descriptor to extract surface features (center position and normal) and refine the predicted grasp point position, removing the need for texture features for vision-guided robot control and sim-to-real modification for DCNN model training. Experimental results demonstrate the efficiency of our system, namely that a robot with 7 degrees of freedom can pick randomly posed textureless boxes in a cluttered environment with a 97.5% success rate at speeds exceeding 1000 pieces per hour.

[Pancreatic arteriovenous malformation perforated into the common bile and pancreatic ducts:a case report].

A 54-year-old man presented with melena and was conservatively monitored for duodenitis. He developed epigastric pain, and dynamic computed tomography revealed abnormal blood flow in the pancreatic head. The endoscopic retrograde cholangiography revealed that the common bile and pancreatic ducts were simultaneously enhanced, thereby indicating the perforation of an arteriovenous malformation into both ducts. Despite medical treatment, the epigastric pain rapidly worsened and therefore, pancreatoduodenectomy was performed. The present report suggests that if the patient's general condition permits, surgical resection should be actively considered for the treatment of symptomatic pancreatic arteriovenous malformation.

[Nonfunctioning pancreatic neuroendocrine tumor with extensive calcification].

A 54-year-old woman exhibited pancreatic calcification on abdominal ultrasonography. Diagnostic imaging revealed a 20-mm mass with a 12-mm calcification in the tail of the pancreas. The mass was weakly enhanced in the early phase of contrast-enhanced CT. We performed pancreatectomy and splenectomy. Histopathological diagnosis was a nonfunctioning pancreatic neuroendocrine tumor (PNET), grade 2. This is a rare case of PNET with extensive calcification.

[Case with gradually enlarging lymphoepithelial cyst of the pancreas that necessitated enucleation].

A 54-year-old man exhibited a pancreatic mass on abdominal ultrasonography. Diagnostic imaging with endoscopic ultrasonography, computed tomography, and magnetic resonance imaging revealed that the mass comprised various internal structures and was not connected to the pancreatic duct. Over a period of 4 years and 2 months, the mass increased from 22mm to 32mm in diameter. Laparoscopic enucleation was performed, and a histopathological diagnosis of a lymphoepithelial cyst (LEC) of the pancreas was obtained. LEC is rare and seldom reported in the literature. Although it is considered to be benign, most case reports indicate that they tend to increase in size. This indicates that LEC should be carefully monitored if surgery is not performed after diagnosis.

Multicenter prospective study for clinical and endoscopic efficacies of leukocytapheresis therapy in patients with ulcerative colitis.

OBJECTIVE: This study aimed to assess the efficacy and tolerability of leukocytapheresis (LCAP) and to investigate predictive factors for mucosal healing and a sustained clinical response in steroid-free and steroid-refractory patients with ulcerative colitis (UC). MATERIAL AND METHODS: Thirty-one steroid-free or steroid-refractory patients with active UC were enrolled. Five or ten consecutive sessions of LCAP were performed in each patient. The efficacy and tolerability was then evaluated at weeks 3 and 6. Endoscopic examination was performed at week 6 to evaluate the mucosal healing, and the sustained cumulative response rate was evaluated at 12 months. RESULTS: At week 6, the mean Mayo clinical activity score had decreased significantly from 8.0 to 4.6 in the steroid-free patients and from 8.3 to 3.9 in the steroid-refractory patients. Rachmilewitz's endoscopic index had also decreased significantly from 9.1 to 6.1 in the steroid-free patients and from 10.0 to 5.7 in the steroid-refractory patients. Forty-seven percent of the steroid-free patients and 33% of the steroid-refractory patients achieved mucosal healing. The peripheral platelet counts had decreased significantly at weeks 3 and 6 in the mucosal healing group, compared with the non-mucosal healing group. The patients with a more than 15% platelet reduction had a significantly higher cumulative response rate, compared with the patients without a platelet reduction (p = 0.015). CONCLUSIONS: LCAP is beneficial for the induction of mucosal healing in steroid-free and steroid-refractory patients with UC. The degree of platelet reduction during LCAP might be a predictive marker for mucosal healing and a sustained clinical response.

Learning Suction Graspability Considering Grasp Quality and Robot Reachability for Bin-Picking.

Deep learning has been widely used for inferring robust grasps. Although human-labeled RGB-D datasets were initially used to learn grasp configurations, preparation of this kind of large dataset is expensive. To address this problem, images were generated by a physical simulator, and a physically inspired model (e.g., a contact model between a suction vacuum cup and object) was used as a grasp quality evaluation metric to annotate the synthesized images. However, this kind of contact model is complicated and requires parameter identification by experiments to ensure real world performance. In addition, previous studies have not considered manipulator reachability such as when a grasp configuration with high grasp quality is unable to reach the target due to collisions or the physical limitations of the robot. In this study, we propose an intuitive geometric analytic-based grasp quality evaluation metric. We further incorporate a reachability evaluation metric. We annotate the pixel-wise grasp quality and reachability by the proposed evaluation metric on synthesized images in a simulator to train an auto-encoder-decoder called suction graspability U-Net++ (SG-U-Net++). Experiment results show that our intuitive grasp quality evaluation metric is competitive with a physically-inspired metric. Learning the reachability helps to reduce motion planning computation time by removing obviously unreachable candidates. The system achieves an overall picking speed of 560 PPH (pieces per hour).

[A case of Cronkhite-Canada syndrome with multiple colon adenomas and early colon cancers].

A 60-year-old man presented with diarrhea and weight loss. Colonoscopy revealed multiple reddish polypoid lesions throughout the gastrointestinal tract and was diagnosed as Cronkhite-Canada syndrome (CCS). Prednisolone therapy caused regression of polyps. Some of them were suspected to be early colon cancers and adenomas. We endoscopically performed mucosal resection for 15 polyps after prednisolone therapy. Histological examination of one of polyps showed invasion of the submucosal layer and colon resection was performed. This case suggests that diagnosis and treatment are important in polyps of CCS.

New practical scoring system to predict post-endoscopic retrograde cholangiopancreatography pancreatitis: Development and validation.

BACKGROUND AND AIM: Post-endoscopic retrograde cholangiopancreatography (ERCP) pancreatitis (PEP) is the most serious adverse event of ERCP. Therefore, it is important to identify high-risk patients who require prophylactic measures. The aim of this study was to develop a practical prediction model for PEP that identifies high-risk patients. METHODS: Patients who underwent ERCP at three tertiary hospitals between April 2010 and September 2012 were enrolled. The dataset was divided into a training set (two centers) and validation set (one center). Using the training set, univariable and multivariable analyses were performed to identify predictive factors for PEP. We constructed a scoring system and evaluated reproducibility using the validation set. RESULTS: A total of 2719 ERCPs were analyzed. PEP developed in 133 cases (4.9%). Risk factors (adjusted odds ratios [OR]) in the training set were a history of PEP (OR: 4.2), intact papilla (OR: 2.4), difficult cannulation (OR: 1.9), pancreatic guidewire-assisted biliary cannulation (OR: 2.2), pancreatic injection (OR: 2.1), pancreatic intraductal ultrasonography (IDUS)/sampling from the pancreatic duct (OR: 2.2), and biliary IDUS/sampling from the biliary tract (OR: 2.8). A scoring system was constructed using these seven clinical variables. The areas under the receiver-operating characteristic curve of this model were 0.799 in the training set and 0.791 in the validation set. In the high-risk group at a score of 3 or higher, the incidence of PEP was 13.4%, and all severe/fatal cases were in the high-risk group. CONCLUSIONS: This scoring system helps to predict each patient's risk and select preventive measures.

[A case of small pancreatic cancer with intraductal progress].

A 60-year-old man was admitted to our department for further evaluation of main pancreatic duct dilatation detected on ultrasonography. Endoscopic retrograde cholangiopancreatography showed stenosis of the main pancreatic duct at the junction of the pancreatic head and body. Brush cytology revealed pancreatic ductal carcinoma. Histological examination of the resected pancreas showed a 15-mm in length intraductal growth of carcinoma in situ in the main pancreatic duct, 10mm of which showed microinvasion. There was also atypical hyperplasia at a branch pancreatic duct near the lesion. It was suspected to be an initial stage of pancreatic ductal carcinoma. Intraductal progression type and non-progression type are often suspected in a case showing progression of carcinoma in situ to pancreatic ductal carcinoma, and this case was thought to be intraductal progression.

Outcomes of Consistent Conservative Management for Acute Cholecystitis Followed by Delayed Cholecystectomy.

OBJECTIVE: This study's objective was to assess outcomes of a totally conservative strategy for acute cholecystitis (AC) followed by delayed elective cholecystectomy. PATIENTS AND METHODS: Consecutive patients who underwent cholecystectomy for AC were divided into the Emergent and Elective cholecystectomy groups. Patients in the elective cholecystectomy group were divided into early, medium, and late groups according to time from symptoms onset. RESULTS: The success rate for conservative management reached 97.2%. Increased blood loss and a higher conversion rate were significantly associated with the emergent group. Patients in the late group had significantly lower operative time and tended to have lower blood loss and less frequent conversion to open surgery than those in the early and medium groups. CONCLUSIONS: Most AC cases could be managed conservatively, and elective cholecystectomy was performed safely regardless of the time. Elective cholecystectomy carried out in late phase was likely to be associated with decreased surgical difficulty.

Current role of percutaneous transhepatic gallbladder aspiration: from palliative to curative management for acute cholecystitis.

BACKGROUND: The present study assessed conservative management of acute cholecystitis (AC) with a focus on percutaneous transhepatic gallbladder aspiration (PTGBA). METHODS: Consecutive 275 patients with AC who underwent PTGBA were reviewed. Patients aged ≥80 years and/or with American Society of Anesthesiologists score III to IV and/or performance status 3 to 4 were defined as high risk. Patients were classified according to duration from symptom onset to first PTGBA: within 3 days (early PTGBA) or over 3 days (late PTGBA). They were also classified according to duration from first PTGBA to surgery: within 30 days (early surgery) or over 30 days (late surgery). RESULTS: A total of 263 patients (95.6%) showed recovery after PTGBA. There were no significant differences in operating time, blood loss, operating procedure, conversion rate to open surgery, postoperative complications, or postoperative hospital stay between the early and late PTGBA groups or between the early and late surgery groups. No significant complications associated with PTGBA or surgery were observed, including in those at high risk. CONCLUSIONS: Percutaneous transhepatic gallbladder aspiration can be a useful alternative for most patients with AC, including those at high risk. Elective cholecystectomy can be performed safely regardless of the timing of PTGBA or surgery.

Role of percutaneous transhepatic gallbladder aspiration in the early management of acute cholecystitis.

OBJECTIVE: Early cholecystectomy is currently the gold standard treatment for acute cholecystitis (AC). However, the acceptability and safety of this strategy remain in dispute. The aim of this study was to clarify the role of percutaneous transhepatic gallbladder aspiration (PTGBA) in the early management of AC in a single center. METHODS: A total of 147 consecutive patients who were treated with PTGBA for AC from 2008 to 2012 were included in the study. The therapeutic outcomes and adverse events were evaluated. RESULTS: A single PTGBA was adequate for 96 (65.3%) patients with AC. Of the remaining 51 patients, 43 (29.3%) showed an improvement after repeated PTGBA and/or percutaneous transhepatic gallbladder drainage (PTGBD), while semi-emergency cholecystectomy was needed in eight patients. Although five patients experienced adverse events (intra-abdominal hemorrhage in two, bile leakage in two and gallbladder hemorrhage in one), no patient died of treatment-related complications. Subsequently, 87 (59.2%) patients underwent cholecystectomy after PTGBA (a single PTGBA in 48 and repeated PTGBA and/or PTGBD in 39 patients). No significant differences were observed in the conversion rate from laparoscopic surgery to open cholecystectomy, operative time or intraoperative hemorrhage volume between the two groups. CONCLUSIONS: The present study demonstrated the safety and acceptability of treatment with PTGBA for AC at our center. This elective treatment strategy may be a useful alternative option in the treatment of AC.

Lifestyle factors associated with gastroesophageal reflux disease in the Japanese population.

BACKGROUND: We aimed to clarify the lifestyle factors associated with erosive esophagitis and non-erosive reflux disease (NERD) in a Japanese population. METHODS: Among 886 subjects who underwent health screening, we selected, according to their scores on the FSSG (frequency scale for symptoms of gastroesophageal reflux disease; GERD) questionnaire and the findings of upper gastrointestinal endoscopy, 138 subjects with erosive esophagitis (EE), 148 subjects with NERD (absence of esophagitis, FSSG score ≥8, and acid reflux-related symptoms score ≥4), and 565 control subjects (absence of esophagitis and FSSG score ≤7). We compared clinical characteristics and various lifestyle factors in these three groups. RESULTS: The lifestyle factors significantly associated with NERD compared with findings in the control group were intake of egg (odds ratio [OR] 1.89, 95% confidence interval [CI] 1.01-3.50), sleep shortage (OR 2.44, 95% CI 1.54-3.88), and strong psychological stress (OR 1.77, 95% CI 1.18-2.62). In male subjects, current smoking (OR 2.06, 95% CI 1.13-3.74; OR 1.87, 95% CI 1.09-3.20) was a significant risk factor for both NERD and EE. Moreover, alcohol >200 kcal/day (OR 3.99, 95% CI 1.03-15.55) and intake of a large quantity of food at supper (OR 7.85, 95% CI 1.66-37.05) were significant risk factors for EE in subjects with hiatal hernia. Intake of a large quantity of food at supper (OR 2.09, 95% CI 1.06-4.13) was more common in the NERD group than in the EE group. CONCLUSIONS: There were differences in the associated lifestyle factors between patients with NERD and those with EE, and there was also a gender-related difference between these groups.