It is currently known that colorectal cancers(CRC) arise from 3 different pathways: the adenoma to carcinoma chromosomal instability pathway(50%-70%); the mutator 'Lynch syndrome' ...route(3%-5%); and the serrated pathway(30%-35%). The World Health Organization has classified serrated polyps into three types of lesions: hyperplastic polyps(HP),sessile serrated adenomas/polyps(SSA/P) and traditional serrated adenomas(TSA),the latter two strongly associated with development of CRCs. HPs do not cause cancer and TSAs are rare. SSA/P appear to be the responsible precursor lesion for the development of cancers through the serrated pathway. Both HPs and SSA/Ps appear morphologically similar. SSA/P are difficult to detect. The margins are normally inconspicuous. En bloc resection of these polyps can hence be troublesome. A careful examination of borders,submucosal injection of a dye solution(for larger lesions) and resection of a rim of normal tissue around the lesion may ensure total eradication of these lesions.
Achalasia: from diagnosis to management Vaezi, Michael F.; Felix, Valter N.; Penagini, Roberto ...
Annals of the New York Academy of Sciences,
October 2016, Letnik:
1381, Številka:
1
Journal Article
Recenzirano
Achalasia is an esophageal motility disorder associated with abnormalities in peristalsis and lower esophageal sphincter (LES) relaxation. The etiology of the disease remains elusive. It is often ...misdiagnosed initially as gastroesophageal reflux disease. Patients with achalasia often complain of dysphagia to solids and liquids but may focus on regurgitation as the primary symptom, leading to the early misdiagnosis. Chest pain, weight loss, and occasional vomiting may be additional symptoms encountered in those with achalasia. The disease may be suspected on the basis of clinical presentation, but diagnosis depends on classic findings using high‐resolution manometry, showing either failed or simultaneous contractions with associated normal or high LES pressures with no or incomplete relaxation with swallows. There are no cures for achalasia, and, in most patients, treatments have to be repeated over time. Definitive treatment options in achalasia include pneumatic dilation, surgical myotomy, and the new technique of per‐oral endoscopic myotomy. Botulinum toxin (Botox) or other medical therapies are often reserved for those who cannot have definitive therapies owing to comorbid conditions.
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There are two challenges associated with the interpretability of deep learning models in medical image analysis applications that need to be addressed: confidence calibration and ...classification uncertainty. Confidence calibration associates the classification probability with the likelihood that it is actually correct – hence, a sample that is classified with confidence X% has a chance of X% of being correctly classified. Classification uncertainty estimates the noise present in the classification process, where such noise estimate can be used to assess the reliability of a particular classification result. Both confidence calibration and classification uncertainty are considered to be helpful in the interpretation of a classification result produced by a deep learning model, but it is unclear how much they affect classification accuracy and calibration, and how they interact. In this paper, we study the roles of confidence calibration (via post-process temperature scaling) and classification uncertainty (computed either from classification entropy or the predicted variance produced by Bayesian methods) in deep learning models. Results suggest that calibration and uncertainty improve classification interpretation and accuracy. This motivates us to propose a new Bayesian deep learning method that relies both on calibration and uncertainty to improve classification accuracy and model interpretability. Experiments are conducted on a recently proposed five-class polyp classification problem, using a data set containing 940 high-quality images of colorectal polyps, and results indicate that our proposed method holds the state-of-the-art results in terms of confidence calibration and classification accuracy.
To analyze through meta-analyses the benefits of two types of stents in the inoperable malignant biliary obstruction.
A systematic review of randomized clinical trials (RCT) was conducted, with the ...last update on March 2015, using EMBASE, CINAHL (EBSCO), MEDLINE, LILACS/CENTRAL (BVS), SCOPUS, CAPES (Brazil), and gray literature. Information of the selected studies was extracted in sight of six outcomes: primarily regarding dysfunction, complication and re-intervention rates; and secondarily costs, survival, and patency time. The data about characteristics of trial participants, inclusion and exclusion criteria and types of stents were also extracted. The bias was mainly assessed through the JADAD scale. This meta-analysis was registered in the PROSPERO database by the number CRD42014015078. The analysis of the absolute risk of the outcomes was performed using the software RevMan, by computing risk differences (RD) of dichotomous variables and mean differences (MD) of continuous variables. Data on RD and MD for each primary outcome were calculated using the Mantel-Haenszel test and inconsistency was qualified and reported in χ (2) and the Higgins method (I (2)). Sensitivity analysis was performed when heterogeneity was higher than 50%, a subsequent assay was done and other findings were compiled. Student's t-test was used for the comparison of weighted arithmetic means regarding secondary outcomes.
Initial searching identified 3660 studies; 3539 were excluded through title, repetition, and/or abstract, while 121 studies were fully assessed and were excluded mainly because they did not compare self-expanding metal stents (SEMS) and plastic stents (PS), leading to thirteen RCT selected, with 13 articles and 1133 subjects meta-analyzed. The mean age was 69.5 years old, that were affected mostly by bile duct (proximal) and pancreatic tumors (distal). The preferred SEMS diameter used was the 10 mm (30 Fr) and the preferred PS diameter used was 10 Fr. In the meta-analysis, SEMS had lower overall stent dysfunction compared to PS (21.6% vs 46.8%, P < 0.00001) and fewer re-interventions (21.6% vs 56.6%, P < 0.00001), with no difference in complications (13.7% vs 15.9%, P = 0.16). In the secondary analysis, the mean survival rate was higher in the SEMS group (182 d vs 150 d, P < 0.0001), with a higher patency period (250 d vs 124 d, P < 0.0001) and a lower cost per patient (4193.98 vs 4728.65 Euros, P < 0.0985).
SEMS are associated with lower stent dysfunction, lower re-intervention rates, better survival, and higher patency time. Complications and costs showed no difference.
What should be done next? Is the stricture benign? Is it resectable? Should I place a stent? Which one? These are some of the questions one ponders when dealing with biliary strictures. In resectable ...cases, ongoing questions remain as to whether the biliary tree should be drained prior to surgery. In palliative cases, the relief of obstruction remains the main goal. Options for palliative therapy include surgical bypass, percutaneous drainage, and stenting or endoscopic stenting (transpapillary or via an endoscopic ultrasound approach). This review gathers scientific foundations behind these interventions. For operable cases, preoperative biliary drainage should not be performed unless there is evidence of cholangitis, there is delay in surgical intervention, or intense jaundice is present. For inoperable cases, transpapillary stenting after sphincterotomy is preferable over percutaneous drainage. The use of plastic stents (PS) has no benefit over Self-Expandable Metallic Stents (SEMS). In case transpapillary drainage is not possible, Endoscopic Ultrasonography- (EUS-) guided drainage is still an option over percutaneous means. There is no significant difference between the types of SEMS and its indication should be individualized.
Background and Aim
Microbiota have been associated with several diseases including colorectal cancer (CRC). This study aimed to evaluate the microbiota in early/invasive CRC utilizing stool and ...cytological brushes to determine differences in relative abundance (RA).
Methods
Colonoscopy patients referred for endoscopic submucosal dissection or previous to CRC surgery were prospectively enrolled. Stool was collected pre‐bowel preparation; and brush samples were taken during colonoscopy (three regions). DNA extraction, 16S rRNA next generation sequencing, and biostatistics (qiime and stamp software packages) followed. Primary outcome was the difference in RA of the Fusobacterium genus between the groups. Secondary outcomes included analyses of other microbiota.
Results
Twenty‐five patients were included, of which 14 had invasive cancer (≥ 1000 mm into the submucosa). The three major genera for invasive cancer were Bacterioides, Oribacterium, and Fusobacterium, whereas for early cancer were Oribacterium, Bacterioides, and Prevotella (decreasing order of RA). There was a significantly higher RA of Fusobacterium in the invasive cancer group (9.65% vs 0.95%, respectively, P < 0.001). The RA of all genera was similar throughout the colon. In addition to Fusobacterium, the genera Corynebacterium, Enterococcus, Neisseria, Porphyromonas, and Sclegelella showed statistically higher RA in the invasive cancer group. Conversely, the genera Oribacterium, Desulfovibrio, Clostridiales, and Lactobacillus showed lower RA in the invasive cancer group.
Conclusions
The RA of Fusobacterium is higher with invasive CRC than in early CRC patients. In addition, five other bacteria genera were found to be increased, and four decreased in invasive CRC patients. The microbiota per patient was similar throughout the colon.
Background and Aim
During COVID‐19 outbreak, restrictions to in‐person consultations were introduced with a rise in telehealth. An indirect benefit of telehealth could be better attendance. This ...study aimed to assess “failure‐to‐attend” (FTA) rate and satisfaction for two endoscopy‐related compulsory telehealth clinics during the COVID‐19 outbreak.
Methods
Consecutive patients booked for endoscopy‐related telehealth clinics at a tertiary hospital were prospectively assessed. In‐person clinic control data were assessed retrospectively. Sample size was calculated to detect an anticipated increase in attendance of 8%. Secondary outcomes included FTA differences between clinics and evaluation of patients and doctors satisfaction. Satisfaction was assessed based on six Likert scale questions used in previous telehealth research and asked to both patients and doctors (6Q_score). This study was exempt from IRB review after institutional IRB review.
Results
There were 691 patients booked for appointments in our endoscopy clinics during the study periods (373 in 2020). FTA rates were lowered by half during the compulsory telehealth clinics (12.6% to 6.4%, P < 0.01). The patient 6Q_score was higher for the advanced endoscopy clinic (84.6% vs 73.8%, P < 0.01), while the doctor 6Q_score was similar between both advanced clinics and post endoscopy clinics (91.1% vs 92.5% respectively, P = 0.80). An in‐person follow‐up consultation was suggested for 3.5% of the appointments, while the necessity of physical examination was flagged in 5.1%.
Conclusions
The use of phone consultations in endoscopy‐related clinics during the COVID‐19 outbreak has improved FTA rates while demonstrating high satisfaction rates. The need for in‐person follow‐up consultations and physical examination were low.
Endoscopy guidelines recommend adhering to policies such as resect and discard only if the optical biopsy is accurate. However, accuracy in predicting histology can vary greatly. Computer-aided ...diagnosis (CAD) for characterization of colorectal lesions may help with this issue. In this study, CAD software developed at the University of Adelaide (Australia) that includes serrated polyp differentiation was validated with Japanese images on narrow-band imaging (NBI) and blue-laser imaging (BLI).
CAD software developed using machine learning and densely connected convolutional neural networks was modeled with NBI colorectal lesion images (Olympus 190 series - Australia) and validated for NBI (Olympus 290 series) and BLI (Fujifilm 700 series) with Japanese datasets. All images were correlated with histology according to the modified Sano classification. The CAD software was trained with Australian NBI images and tested with separate sets of images from Australia (NBI) and Japan (NBI and BLI).
An Australian dataset of 1235 polyp images was used as training, testing, and internal validation sets. A Japanese dataset of 20 polyp images on NBI and 49 polyp images on BLI was used as external validation sets. The CAD software had a mean area under the curve (AUC) of 94.3% for the internal set and 84.5% and 90.3% for the external sets (NBI and BLI, respectively).
The CAD achieved AUCs comparable with experts and similar results with NBI and BLI. Accurate CAD prediction was achievable, even when the predicted endoscopy imaging technology was not part of the training set.
Background and Aim
Cholecystectomy and endoscopic retrograde cholangiopancreatography are the gold standard for managing acute cholecystitis and malignant biliary obstruction, respectively. Recent ...advances in therapeutic endoscopic ultrasound (EUS) have provided alternatives for managing patients in whom these approaches fail, namely, EUS‐guided gallbladder drainage (EUS‐GB) and EUS‐guided bile duct drainage (EUS‐BD). We aimed to assess the technical and clinical success of these techniques in the largest multicenter cohort published to date.
Methods
A retrospective, multicenter, observational study involving 17 centers across Australia and New Zealand was conducted. All patients who had EUS‐GB or EUS‐BD performed in a participating center using a lumen apposing metal stent between 2016 and 2020 were included. Primary outcome was technical success, defined as intra‐procedural successful drainage. Secondary outcomes included clinical success and 30‐day mortality.
Results
One hundred and fifteen patients underwent EUS‐GB (n = 49) or EUS‐BD (n = 66). EUS‐GB was technically successful in 47 (95.9%) while EUS‐BD was successful in 60 (90.9%). All failed cases were due to maldeployment of the distal flange outside of the targeted lumen. Clinical success of EUS‐GB was achieved in 39 (79.6%). No patients required subsequent cholecystectomy. Clinical success of EUS‐BD was achieved in 52 (78.8 %). Thirty‐day mortality was 14.3% for EUS‐GB and 12.1% for EUS‐BD.
Conclusions
EUS‐guided gallbladder drainage and EUS‐BD are promising alternatives for managing nonsurgical candidates with cholecystitis and malignant biliary obstruction following failed endoscopic retrograde pancreatography. Both techniques delivered high technical success with acceptable clinical success. Further research is needed to investigate the gap between technical and clinical success.
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