Diagnostic Performance of Endoscopic Ultrasound Elastography for Differential Diagnosis of Gallbladder Polyp.

BACKGROUND AND AIMS: It is difficult to differentiate between neoplastic and non-neoplastic gallbladder (GB) polyps before surgery. Endoscopic ultrasound-elastography (EUS-EG) is a non-invasive complementary diagnostic method. The utility of EUS-EG in the differential diagnosis of GB polyps has not been investigated. We aimed to investigate the diagnostic performance of EUS-EG for the differential diagnosis of GB polyps. METHODS: Patients with GB polyps were prospectively enrolled from June 2020 until November 2022. EUS-EG and semi-quantitative evaluation of the strain ratio (SR) were performed for differential diagnosis of GB polyps. Fifty-three eligible patients were divided into two groups based on the final diagnosis after surgery. Patient demographics, EUS characteristics, and SR values were compared. Receiver-operating characteristic (ROC) curve analysis was performed to determine the optimal cutoff SR value that discriminates between neoplastic and non-neoplastic GB polyps. RESULTS: The median SR value for neoplastic polyps (32.93 [interquartile range: 22.37-69.02]) was significantly higher than for non-neoplastic polyps (5.40 [2.36-14.44]; p<0.001). There were significant differences in SR values between non-neoplastic, benign neoplastic (23.38 [13.62-39.04]), and malignant polyps (49.25 [27.90-82.00]). The optimal cut-off SR value to differentiate between neoplastic and non-neoplastic polyps was 18.4. In multivariable logistic regression, SR value >18.4 (odds ratio 33.604, 95% confidence interval 2.588-436.292) was an independent predictor of neoplastic polyps. CONCLUSIONS: EUS-EG and SR values can be used as a supplementary method for evaluating GB polyps.

A comparison of novel electrocautery-enhanced lumen-apposing metal stents and plastic stents in EUS-guided drainage of infected walled-off necrosis: A multicenter randomized study.

BACKGROUND AND STUDY AIMS: Although lumen-apposing metal stents (LAMSs) have been increasingly used for walled-off necrosis (WON), their advantages over plastic stents (PS) in infected WON are unclear. We investigated the safety and efficacy of novel electrocautery-enhanced LAMS (EC-LAMS) for managing infected WON. PATIENTS AND METHODS: Patients who underwent endoscopic ultrasound-guided WON drainage were randomly assigned to the LAMS or PS groups. The primary outcome was the total number of direct endoscopic necrosectomy (DEN) procedures required to achieve clinical success. The secondary outcomes included technical success, clinical success, and adverse event occurrence. RESULTS: Forty-six patients were divided into the LAMS or PS groups (n=23 each). The total number of DEN procedures did not differ significantly between the PS (four procedures, interquartile range [IQR] 2.5-5.0) and LAMS groups (nine procedures, IQR: 8.0-9.0) (P=0.07). The LAMS group demonstrated a significantly higher clinical success rate than the PS group based on intention-to-treat analysis (100% vs. 73.9%, P=0.03) at 8 weeks but not at 4 weeks. No significant bleeding events were reported in the LAMS group, and one was reported in the PS group. CONCLUSIONS: We found no significant difference in the total number of DEN procedures between LAMS and PS for managing infected WON. The only statistically significant finding was a higher clinical success rate at 8 weeks for patients treated with EC-LAMS. The use of EC-LAMS did not result in any adverse events, such as bleeding or buried LAMS syndrome, within the study duration.

Side-by-side placement of fully covered metal stents versus conventional 7F plastic stents in malignant hilar biliary obstruction: Prospective randomized controlled trial.

OBJECTIVES: We aimed to evaluate the efficacy and safety of metal stents compared with plastic stents when bilateral side-by-side stents were deployed for malignant hilar biliary obstruction (MHBO). METHODS: Fifty patients with unresectable advanced MHBO were randomly assigned to the metal stent (MS, n = 25) or plastic stent group (PS, n = 25). Fully covered self-expandable metal stents with 6 mm diameter and plastic stents with either 7F straight or double pigtail were used for MS and PS groups, respectively. Time to recurrent biliary obstruction (TRBO) was evaluated as the primary outcome. RESULTS: Both groups had 100% technical success rates; 88% and 76% of clinical success rates were obtained in MS and PS, respectively. Although stent migrations were more frequent in MS than PS (48% vs. 16%, P = 0.02), the mean TRBO was significantly longer in MS (190 days; 95% confidence interval [CI] 121-260 days vs. 96 days; 95% CI 50-141 days, P = 0.02). The placement of plastic stents (hazard ratio 2.42; 95% CI 1.24-4.73; P = 0.01) was the only significant risk factor associated with TRBO in multivariable analysis. The rates of adverse events were similar between the two groups (difference 0%; 95% CI -25% to 25%; P > 0.99). CONCLUSIONS: During bilateral side-by-side deployment in MHBO, the use of metal stents appears to be preferable to plastic stents in terms of TRBO, despite a higher frequency of stent migration.

A population-based cohort study on risk factors for acute pancreatitis: A comparison by age group.

BACKGROUND: /objectives: Acute pancreatitis (AP) is an acute inflammatory disorder that can occur in all age groups. The risk of AP has been shown to increase with age. However, no study has compared risk factors for AP according to age group yet. Thus, the aim of this study was to perform such comparison. METHODS: Clinical data from individuals 20 years of age and older who received a health examination arranged by the Korean national health insurance program in 2009 (n = 4,238,822) were used. First-attack AP was identified using claims data from baseline to December 2018. Incidence and risk factors of AP were analyzed for young (20-39 years old), middle-aged (40-64 years old), and old (over 65 years old) groups. RESULTS: Incidences of AP in young, middle-aged, and old groups were 16.30, 27.85, and 57.19 per 100,000 person-years, respectively. Smoking, alcohol drinking, diabetes, gallstone, and chronic pancreatitis were associated with increased risk of AP in all age groups. Meanwhile, male, older age, and higher waist circumference were associated with increased risk of AP in middle-aged and old groups. In young and middle-aged groups, risk of AP was increased in the presence of hypertension and dyslipidemia. However, high income was associated with decreased risk of AP in these groups. CONCLUSIONS: In this population-based cohort study, incidences and risk factors for AP differed according to age group. Thus, a tailored strategy might be needed to prevent AP according to age group.

Prolonged patency of fully covered self-expandable metal stents with an externally anchored plastic stent in distal malignant biliary obstruction.

BACKGROUND : Fully covered self-expandable metal stents (FCSEMSs) are widely used for endoscopic treatment of distal malignant biliary obstruction (dMBO). We aimed to assess the efficacy of anchoring an external plastic stent to an FCSEMS in dMBO. METHODS : A multicenter retrospective cohort study was performed in patients with dMBO to compare stent patency between FCSEMSs and FCSEMSs with an externally anchored plastic stent (EPS). For external anchoring, a 7-Fr double-pigtail plastic stent (DPPS) was placed first in the bile duct, then an FCSEMS was deployed side-by-side. RESULTS : Among a total of 185 patients, 65 had an FCSEMS alone and 120 had an FCSEMS with an EPS. The median stent patency was significantly longer in the FCSEMS with an EPS group than in the FCSEMS only group (342 vs. 240 days; P = 0.04). The rate of stent migration was significantly lower in the FCSEMS with an EPS group than in the FCSEMS only group (10.8 % vs. 27.7 %; P = 0.01). There were no significant differences in the rates of stent occlusion and adverse events between the two groups. CONCLUSIONS : A novel and simple technique of anchoring an external plastic stent may decrease the risk of FCSEMS migration and prolong stent patency, without significantly increasing the adverse events rate in dMBO.

Combination of chemotherapy and focused ultrasound for the treatment of unresectable pancreatic cancer: a proof-of-concept study.

OBJECTIVES: To investigate the safety and preliminary efficacy of the combined treatment of focused ultrasound (FUS) and chemotherapy (nab-paclitaxel plus gemcitabine, nPac/Gem) for patients with unresectable pancreatic cancer. METHODS: Patients pathologically diagnosed with unresectable pancreatic cancer were included. Low (Isppa = 1.5 kW/cm2), intermediate (2.0 kW/cm2), and high (2.5 kW/cm2) FUS intensity treatment groups were predefined. A 1% duty cycle and the 3+3 scheme were used. Six combined treatments were performed, and adverse events were assessed. Changes in tumor size and tumor response, CA 19-9 level, and patient-reported outcomes at the immediate follow-up (F/U) and/or at the 3-month F/U and survival were evaluated. RESULTS: Three participants were enrolled in each intensity group. No adverse device effect or dose-limiting toxicity occurred in any of the participants. Seven of the nine participants experienced a >15% tumor size decrease at the immediate F/U CT and at the 3-month F/U CT. The CA 19-9 level decreased in all of the participants at the immediate F/U. All participants in the intermediate-intensity treatment group showed a > 30% tumor size decrease, partial response, and a significant decrease in the CA 19-9 level at 3-month F/U and longer survival (p < 0.05). CONCLUSION: FUS with an intensity of 1.5 to 2.5 kW/cm2 was safe in the combined treatment of FUS and nPac/Gem. Considering the results of the change in tumor size, the change in CA 19-9 level, tumor response, and survival, these FUS parameters can be used for subsequent clinical trials. KEY POINTS: • No adverse device effect or dose-limiting toxicity occurred in any of the participants when focused ultrasound with an intensity of 1.5-2.5 kW/cm2 and a low duty cycle of 1% was combined with chemotherapy. • The intermediate-intensity group showed a >30% tumor size decrease, partial response, and a significant decrease in CA 19-9 in all of the participants at the 3-month follow-up and the longest survival. • Any focused ultrasound setting used in this study could be safe and optimal for subsequent clinical trials.

The association between smoking, changes in smoking behavior, and acute pancreatitis: A population-based cohort study in Korea.

BACKGROUND AND AIMS: In the Asian population, existing studies regarding the association between smoking and acute pancreatitis are few in number. The aim of this study was to investigate the incidence of acute pancreatitis according to smoking habits and smoking habit changes of the Korean population. METHODS: We used clinical data from individuals (aged 20 years or older) who received health examinations arranged by the Korean National Health Insurance Service in 2009 (n = 4 238 822) or in 2009 and 2011 (n = 2 617 306). The incidence of acute pancreatitis was analyzed according to smoking status or smoking habit change reported by individuals during their health examination. Newly diagnosed acute pancreatitis was identified using claims data from baseline to the date of diagnosis or until December 31, 2018. RESULTS: The risk of acute pancreatitis was significantly higher in current smokers compared with never-smokers regardless of age or sex. The adjusted hazard ratio (HR) of acute pancreatitis in current smokers increased according to the amount of smoking (HR 1.28; 95% confidence interval [CI], 1.12-1.45 in <10 cigarettes/day, HR 1.4; CI, 1.3-1.52 in 10-19 cigarettes/day, HR 1.66; CI, 1.55-1.78 in ≥20 cigarettes/day). The adjusted HR of acute pancreatitis in continuous smokers was 1.66 (CI, 1.53-1.8) compared with never-smokers and was higher than smokers who quit smoking (HR 1.34; CI, 1.17-1.54). CONCLUSIONS: In this Korean population-based cohort study, smoking increased the incidence of acute pancreatitis in a dose-dependent manner, and smoking cessation helped decrease the incidence of acute pancreatitis.

Efficacy and predictive factors of endoscopic ultrasound-guided ethanol ablation in benign solid pancreatic tumors.

BACKGROUNDS AND OBJECTIVES: Endoscopic ultrasound-guided ethanol ablation (EUS-EA) has recently been introduced for the management of solid pancreatic tumors, including pancreatic neuroendocrine tumors (PNETs) and solid pseudopapillary tumors (SPTs). The study aims to evaluate the efficacy and predictive factors for response of EUS-EA in solid pancreatic tumors. METHODS: Between October 2015 and July 2021, 72 patients who underwent EUS-EA for solid pancreatic tumors were included. The study outcomes were to evaluate the efficacy of EUS-EA with complete remission (CR) and objective response, and their predictive factors. RESULTS: During follow-up, 47 patients were diagnosed with PNETs and 25 with SPTs. Eight cases reached CR and 48 reached objective response. When compared with SPTs, PNETs showed similar duration to reach CR (median not reached; p = 0.319), but shorter duration to reach objective response (PNETs: median 20.6 months, 95%CI 10.26-30.88; SPTs: median 47.7 months, 95%CI 18.14-77.20; p = 0.018). Ethanol dosage > 0.35 ml/cm3 shortened the duration to reach CR (median not reached; p = 0.026) and objective response (median 42.5 months, 95%CI 25.34-59.66 vs. 19.6 months, 95%CI 10.17-29.09; p = 0.006). CR had no significant predictive factors, but PNETs showed significant predictive factors for objective response (HR 3.34, 95%CI 1.07-10.43; p = 0.038). Twenty-seven patients experienced adverse events, and there were two severe cases. CONCLUSION: EUS-EA for pancreatic solid lesions seems feasible as a local treatment for patients who refuse or are unfit for surgery. Additionally, PNETs seem to be the better candidate for EUS-EA.

Usefulness of Liquid-Based Cytology in Diagnosing Biliary Tract Cancer Compared to Conventional Smear and Forceps Biopsy.

BACKGROUND/AIMS: Liquid-based cytology (LBC) has been shown to improve the diagnostic efficacy of brush cytology for thyroid, cervical and pancreatic cancer. To evaluate the diagnostic performance of LBC for biliary tract cancer, we compared it with conventional smears and forceps biopsies. METHODS: A retrospective study was conducted of all consecutive patients who underwent brush cytology under ERCP from January 2010 to April 2020. The primary outcome was the diagnostic efficacy of conventional smears and LBC. The difference between the two groups was corrected using inverse probability weighting (IPW). The secondary outcome was the sensitivity and specificity of brush cytology and forceps biopsy. The secondary outcome was evaluated in patients who underwent both methods. RESULTS: Among 162 patients, conventional smears were performed in 70 patients and LBC was performed in 92 patients. In the primary analysis using IPW, the sensitivity of conventional smears and LBC was 56.00% and 78.26% respectively (P = 0.009). The specificity was 100% for both methods. The accuracy was 66.15% for conventional smears and 83.33% for LBC (P = 0.012). In the secondary analysis, the sensitivity of conventional smears versus forceps biopsies was 62.16% versus 78.38% (P = 0.034) and 81.16% for both LBC and forceps biopsies. The specificity of both cytological examination and forceps biopsies was 100%. CONCLUSIONS: Liquid-based cytology demonstrated better sensitivity and accuracy than conventional smears. Moreover, its diagnostic performance was close to that of forceps biopsies.

The natural course of incidental ureteral polyp during ureteroscopic surgery: KSER research.

BACKGROUND: The natural course of polypoid lesions in the ureter during ureteroscopic stone surgery was not yet clarified. METHODS: Patient data were collected prospectively from six teaching hospitals between 2019 and 2021. Patients with polypoid lesions in the ureter distal to ureteral stones were included during ureteroscopy. Computed tomography was performed on all enrolled patients three months after the procedure. Follow-up ureteroscopy was performed only if the patient consented, due to the need for general anesthesia and ethical considerations. RESULTS: Among the 35 patients who were followed up, 14 had fibroepithelial polyps and 21 had inflammatory polyps. Twenty of the followed-up patients underwent ureteroscopy, and nine of them had fibroepithelial polyps. Although fibroepithelial polyps did not disappear in the follow-up ureteroscopy (p = 0.002), the rate of postoperative hydronephrosis was not higher in the fibroepithelial group than in the inflammatory group. Postoperative ureteral stricture and moderate-to-severe hydronephrosis were found to be closely related to the number of resected polyps, regardless of the type of polyp (p = 0.014 and 0.006, respectively). CONCLUSION: Fibroepithelial polyps in the ureter may persist after treatment of adjacent ureter stones. However, conservative management may be preferable to active removal of ureteral polyps because fibroepithelial polyps may not contribute to clinically significant hydronephrosis after surgery, and inflammatory polyps disappear spontaneously. Hasty resections of polyps may increase the risk of ureteral stricture.

A Deep Learning-Based Semantic Segmentation Model Using MCNN and Attention Layer for Human Activity Recognition.

With the development of wearable devices such as smartwatches, several studies have been conducted on the recognition of various human activities. Various types of data are used, e.g., acceleration data collected using an inertial measurement unit sensor. Most scholars segmented the entire timeseries data with a fixed window size before performing recognition. However, this approach has limitations in performance because the execution time of the human activity is usually unknown. Therefore, there have been many attempts to solve this problem through the method of activity recognition by sliding the classification window along the time axis. In this study, we propose a method for classifying all frames rather than a window-based recognition method. For implementation, features extracted using multiple convolutional neural networks with different kernel sizes were fused and used. In addition, similar to the convolutional block attention module, an attention layer to each channel and spatial level is applied to improve the model recognition performance. To verify the performance of the proposed model and prove the effectiveness of the proposed method on human activity recognition, evaluation experiments were performed. For comparison, models using various basic deep learning modules and models, in which all frames were classified for recognizing a specific wave in electrocardiography data were applied. As a result, the proposed model reported the best F1-score (over 0.9) for all kinds of target activities compared to other deep learning-based recognition models. Further, for the improvement verification of the proposed CEF method, the proposed method was compared with three types of SW method. As a result, the proposed method reported the 0.154 higher F1-score than SW. In the case of the designed model, the F1-score was higher as much as 0.184.

Accelerated Pancreatobiliary MRI for Pancreatic Cancer Surveillance in Patients With Pancreatic Cystic Neoplasms.

BACKGROUND: Pancreatobiliary MRI is often recommended for patients at risk of developing pancreas cancer. But the surveillance MRI protocol has not yet been widely accepted. PURPOSE: To establish an accelerated MRI protocol targeting the table time of 15 minutes for pancreatic cancer surveillance and test its performance in lesion characterization. STUDY TYPE: Prospective. POPULATION: A total of 30 participants were enrolled, who were undergoing follow-up care for intraductal papillary mucinous neoplasms or newly diagnosed pancreatic cysts (≥10 mm) and were scheduled for or had recently undergone contrast-enhanced CT (CECT). FIELD STRENGTH/SEQUENCE: A 3 T; heavily T2WI, 3D MRCP, DWI, dynamic T1WI, two-point Dixon. ASSESSMENT: In-room time and table time were measured. Seven radiologists independently reviewed image quality of MRI and then the presence of high-risk stigmata and worrisome features in addition to diagnostic confidence for accelerated MRI, CECT, and the noncontrast part of accelerated MRI (NC-MRI). STATISTICAL ANALYSIS: Fisher's exact test was used for categorical variables and either the Student's t-test or Mann-Whitney test was performed for continuous variables. The generalized estimated equation was used to compare the diagnostic performance of examinations on a per-patient basis. Interobserver agreement was evaluated via Fleiss kappa. A P value of <0.05 was considered to be statistically significant. RESULTS: The in-room time was 18.5 ± 2.6 minutes (range: 13.7-24.9) and the table time was 13.9 ± 1.9 minutes (range: 10.7-17.5). There was no significant difference between the diagnostic performances of the three examinations (pooled sensitivity: 75% for accelerated MRI and CECT, 68% for NC-MRI, P = 0.95), with the highest significant diagnostic confidence for accelerated MRI (4.2 ± 0.1). With accelerated MRI, the interobserver agreement was fair to excellent for high-risk stigmata (κ = 0.34-0.98). DATA CONCLUSION: Accelerated MRI protocol affords a table time of 15 minutes, making it potentially suitable for cancer surveillance in patients at risk of developing pancreatic cancer. EVIDENCE LEVEL: 2 TECHNICAL EFFICACY STAGE: 2.

The effect of nafamostat mesilate infusion after ERCP for post-ERCP pancreatitis.

BACKGROUND: Nafamostat mesilate decreases the incidence of pancreatitis after endoscopic retrograde cholangiopancreatography (ERCP). However, no studies have administered nafamostat mesilate after ERCP. So we investigated if the infusion of nafamostat mesilate after ERCP can affect the post-ERCP pancreatitis (PEP) in high-risk patients. METHODS: In a tertiary hospital, 350 high-risk patients of PEP were reviewed retrospectively. Among them, 201 patients received nafamostat mesilate after ERCP. Patient-related and procedure-related risk factors for PEP were collected. We performed a propensity score matching to adjust for the significant different baseline characteristics. The incidence and severity of PEP were evaluated according to the infusion of nafamostat mesilate. The risk factors of PEP were also analyzed by multivariate logistic regression. RESULTS: The baseline characteristics were not different after the matching. The PEP rate (17.4% vs. 10.3%, P = 0.141) was insignificant. Among the PEP patients, mild PEP was significantly higher in the nafamostat mesilate group (85.7% vs. 45.5%, P = 0.021). Only one patient in the nafamostat mesilate group developed severe PEP. Although young age (odds ratio [OR] 3.60, 95% CI 1.09-11.85, P = 0.035) was a risk factor, nafamostat mesilate (odds ratio [OR] 0.30, 95% CI 0.09-0.98, P = 0.047) was a protective factor for moderate to severe PEP. CONCLUSIONS: The administration of nafamostat mesilate after ERCP in high-risk patients was not effective in preventing PEP, but may attenuate the severity of PEP.

Predicting factor analysis of postoperative complications after robot-assisted radical cystectomy: Multicenter KORARC database study.

OBJECTIVES: To evaluate postoperative complications following robot-assisted radical cystectomy in patients diagnosed with bladder cancer and reveal if there are predictors for postoperative complications. METHODS: Prospectively collected medical records of 730 robot-assisted radical cystectomy patients between 2007/04 and 2019/05 in 13 tertiary referral centers were reviewed. Perioperative outcomes were compared between two groups by postoperative complications (complication vs non-complication). We assessed recurrence-free survival, cancer-specific survival, and overall survival between groups. Regression analyses were implemented to identify factors associated with postoperative complications. RESULTS: Any total and high-grade complication (Clavien-Dindo grade ≥3) rates were 57.8% and 21.1%, respectively. Patients in complication group had significantly higher proportion of diabetes mellitus (P = 0.048), chronic kidney disease (P = 0.011), dyslipidemia (P < 0.001), longer operation time (P = 0.001), more estimated blood loss (P = 0.001), and larger intraoperative fluid volume (P < 0.001). There was a significant difference in cancer-specific survival (log-rank P = 0.038, median cancer-specific survival: both groups not reached). Dyslipidemia (odds ratio 2.59, P = 0.002) and intraoperative fluid volume (odds ratio 1.0002, P = 0.040) were significantly associated with high-grade postoperative complications. Diabetes mellitus (odds ratio 1.97, P = 0.028), chronic kidney disease (odds ratio 1.89, P = 0.046), dyslipidemia (odds ratio 5.94, P = 0.007), and intraoperative fluid volume (odds ratio 1.0002, P = 0.009) were significantly associated with any postoperative complications. CONCLUSIONS: Patients with diabetes mellitus, chronic kidney disease, dyslipidemia, or a relatively large intraoperatively infused fluid volume are more likely to develop postoperative complications. Patients with postoperative complications might have a possibility of lower cancer-specific survival rate.

Acetylsalicylic acid for metal stent in malignant distal common bile duct obstruction: A randomized controlled trial.

BACKGROUND: Endoscopic biliary drainage is the treatment of choice for patients with malignant distal common bile duct obstruction. Self-expandable metal stents have clinical advantages including an increased duration of patency that may be prolonged by acetylsalicylic acid (ASA) use. The aim of this study was to investigate whether ASA had a positive effect on the patency of self-expandable metal stents compared with placebo. METHODS: This prospective, multicenter, double-blinded, and randomized placebo-controlled trial was conducted from October 2017 to May 2020 in Korea. Patients who underwent palliative endoscopic biliary drainage with self-expandable metal stents for malignant distal bile duct obstruction were enrolled, and allocated to ASA treatment or placebo. The study outcomes were the rate of stent dysfunction at 6 months, duration of stent patency, risk factors for stent dysfunction, and any adverse events. RESULTS: Interim analysis included 24 and 28 patients in the ASA and placebo groups, respectively. There was no significant difference between the ASA and placebo groups in stent dysfunction (25.0% vs. 20.7%, P = 0.761) or the duration of stent patency (150.97 ± 10.55 vs. 158.07 ± 8.70 days, P = 0.497). Six patients experienced suspected ASA-related adverse events, and there was one lethal case. CONCLUSIONS: ASA did not prolong stent patency. This study was terminated early because of the possibility of serious adverse events related to ASA treatment of these patients receiving palliative care.

Markerless 3D Skeleton Tracking Algorithm by Merging Multiple Inaccurate Skeleton Data from Multiple RGB-D Sensors.

Skeleton data, which is often used in the HCI field, is a data structure that can efficiently express human poses and gestures because it consists of 3D positions of joints. The advancement of RGB-D sensors, such as Kinect sensors, enabled the easy capture of skeleton data from depth or RGB images. However, when tracking a target with a single sensor, there is an occlusion problem causing the quality of invisible joints to be randomly degraded. As a result, multiple sensors should be used to reliably track a target in all directions over a wide range. In this paper, we proposed a new method for combining multiple inaccurate skeleton data sets obtained from multiple sensors that capture a target from different angles into a single accurate skeleton data. The proposed algorithm uses density-based spatial clustering of applications with noise (DBSCAN) to prevent noise-added inaccurate joint candidates from participating in the merging process. After merging with the inlier candidates, we used Kalman filter to denoise the tremble error of the joint's movement. We evaluated the proposed algorithm's performance using the best view as the ground truth. In addition, the results of different sizes for the DBSCAN searching area were analyzed. By applying the proposed algorithm, the joint position accuracy of the merged skeleton improved as the number of sensors increased. Furthermore, highest performance was shown when the searching area of DBSCAN was 10 cm.

Comparison between FOLFIRINOX and gemcitabine plus nab-paclitaxel including sequential treatment for metastatic pancreatic cancer: a propensity score matching approach.

BACKGROUND: FOLFIRINOX (FFX) and Gemcitabine plus nab-paclitaxel (GnP) have been recommended as the first-line chemotherapy for metastatic pancreatic cancer (mPC). However, the evidence is lacking comparing not only two regimens, but also sequential treatment (FFX-GnP vs. GnP-FFX). METHODS: Data of 528 patients (FFX, n = 371; GnP, n = 157) with mPC were collected retrospectively. Propensity score matching was conducted to alleviate imbalance of the two groups. Overall survival (OS), progression free survival (PFS), and toxicity of patients were analyzed. RESULTS: In the whole population, OS (12.5 months vs. 10.3 months, P = 0.05) and PFS (7.1 months vs. 5.8 months, P = 0.02) were longer in the FFX group before matching and after matching (OS: 11.8 months vs. 10.3 months, P = 0.02; PFS: 7.2 months vs. 5.8 months, P <  0.01). For sequential treatment, OS and PFS showed no significant difference. Interruptions of chemotherapy due to toxicities were more frequent (6.8 vs. 29.3%, P <  0.001) in the GnP group, and cessation of chemotherapy showed a significant association with mortality (z = - 1.94, P = 0.03). CONCLUSIONS: FFX achieved a longer overall survival than GnP in mPC, but not in the comparison for sequential treatment. More frequent adverse events followed by treatment interruptions during GnP might lead to a poor survival outcome. Therefore, FFX would be a better first-line treatment option than GnP for mPC.

Efficacy of an internal anchoring plastic stent to prevent migration of a fully covered metal stent in malignant distal biliary strictures: a randomized controlled study.

BACKGROUND: Two types of self-expandable metal stents (SEMS) are available for malignant distal biliary obstruction: fully covered SEMS (FCSEMS) and uncovered SEMS. FCSEMS can prevent stent ingrowth, but a major concern is spontaneous migration. This study aimed to determine whether the additional insertion of a double-pigtail plastic stent to anchor the FCSEMS can prevent migration. METHODS: 68 patients with unresectable, malignant, distal, biliary obstruction were included in this multicenter, randomized, superiority trial. The patients were randomly assigned to receive either the FCSEMS plus an anchoring plastic stent (n = 33) or an FCSEMS alone (n = 35). After placement of the FCSEMS, the anchoring stent was inserted inside the FCSEMS. The primary outcome was the rate of stent migration during the 6-month follow-up. The secondary outcomes were stent-related adverse events, stent patency, and survival rates. RESULTS: The baseline characteristics were similar between the two groups. The rate of stent migration at 6 months was significantly lower in patients with the FCSEMS plus anchoring stent (15 % vs. 40 %; P = 0.02). The mean stent patency was significantly longer in the FCSEMS plus anchoring group (237 days [95 % confidence interval [CI] 199 to 275] vs. 173 days [95 %CI 130 to 217]; P = 0.048). There were no significant differences in stent-related adverse events and overall survival rates at 6 months between the two groups. CONCLUSIONS: Our data suggest that the additional double-pigtail plastic stent anchored the FCSEMS to prevent migration and prolonged patency without any serious adverse events.

Histogram of kidney stones on non-contrast computed tomography to predict successful stone dusting during retrograde intrarenal surgery.

PURPOSE: To predict successful dusting of kidney stones during retrograde intrarenal surgery (RIRS) using stone density parameters and histograms measured with non-contrast computed tomography imaging. METHODS: Medical records of 49 patients who underwent retrograde intrarenal surgery between January 2018 and January 2019 at Kyung Hee University Hospital were reviewed, and the data of 55 stones were evaluated. Patient age, sex, mean stone density, the highest and lowest measured Hounsfield unit (HU), standard deviation and range of the measured HUs, volume of the most measured HU, and success of dusting were evaluated. Histograms of the measured HUs were created and cutoff values for successful dusting were analyzed. RESULTS: Thirty-two stones were successfully dusted during surgery. Dusted stones had a wider range of HU and higher standard deviation. The volume of the most measured HU was smaller in the dusted stones. Successful dusting could be predicted when the volume of the most measured HU was < 8.9 mm3, with range ≥ 853, or when the volume of the most measured HU was < 8.9 mm3, with range < 853, and the mean stone density was < 355. The histograms of HUs of the dusted stones were wide and rugged, while those of dusting failed stones were narrow and peaked. CONCLUSION: Evaluation of stone HU histograms showed differences in distribution and proportion. This will help predict surgical outcomes and prepare for intraoperative complications.

Optimal timing of endoscopic retrograde cholangiopancreatography for acute cholangitis associated with distal malignant biliary obstruction.

BACKGROUND: There is a lack of studies regarding the optimal timing for endoscopic retrograde cholangiopancreatography (ERCP) in patients with cholangitis caused by distal malignant biliary obstruction (MBO). This study aims to investigate the optimal timing of ERCP in patients with acute cholangitis associated with distal MBO with a naïve papilla. METHODS: A total of 421 patients with acute cholangitis, associated with distal MBO, were enrolled for this study. An urgent ERCP was defined as being an ERCP performed within 24 h following emergency room (ER) arrival, and early ERCP was defined as an ERCP performed between 24 and 48 h following ER arrival. We evaluated both 30-day and 180-day mortality as primary outcomes, according to the timing of the ERCP. RESULTS: The urgent ERCP group showed the lowest 30-day mortality rate (2.2%), as compared to the early and delayed ERCP groups (4.3% and 13.5%) (P < 0.001). The 180-day mortality rate was lowest in the urgent ERCP group, followed by early ERCP and delayed ERCP groups (39.4%, 44.8%, 60.8%; P = 0.006). A subgroup analysis showed that in both the primary distal MBO group, as well as in the moderate-to-severe cholangitis group, the urgent ERCP had significantly improved in both 30-day and 180-day mortality rates. However, in the secondary MBO and mild cholangitis groups, the difference in mortality rate between urgent, early, and delayed ERCP groups was not significant. CONCLUSIONS: In patients with acute cholangitis associated with distal MBO, urgent ERCP might be helpful in improving the prognosis, especially in patients with primary distal MBO or moderate-to-severe cholangitis.