RadFormer: Transformers with Global-Local Attention for Interpretable and Accurate Gallbladder Cancer Detection

We propose a novel deep neural network architecture to learn interpretable representation for medical image analysis. Our architecture generates a global attention for region of interest, and then learns bag of words style deep feature embeddings with local attention. The global, and local feature maps are combined using a contemporary transformer architecture for highly accurate Gallbladder Cancer (GBC) detection from Ultrasound (USG) images. Our experiments indicate that the detection accuracy of our model beats even human radiologists, and advocates its use as the second reader for GBC diagnosis. Bag of words embeddings allow our model to be probed for generating interpretable explanations for GBC detection consistent with the ones reported in medical literature. We show that the proposed model not only helps understand decisions of neural network models but also aids in discovery of new visual features relevant to the diagnosis of GBC. Source-code and model will be available at https://github.com/sbasu276/RadFormerComment: To Appear in Elsevier Medical Image Analysi

SIGNIFICANCE OF ROBOTIC CHOLECYSTECTOMY OVER LAPAROSCOPIC CHOLECYSTECTOMY IN THE MANAGEMENT OF CHOLECYSTITIS: A CASE STUDY OF FACTORS INFLUENCING PATIENTS’ DECISION AT A HOSPITAL IN TEXAS, USA

The increasing cases of cholecystitis (gallbladder inflammation) among the patient population call for more corrective measures to improve clinical outcomes. Notably, LC (laparoscopic cholecystectomy) was the standard surgical procedure for managing gallbladder ailment. However, with technological advancement, a robotic-aided technique (robotic cholecystectomy) was introduced based on the idea that it improves on some of the shortcomings associated with LC. Notably, RC involves a single incision, hence, it is less invasive than LC. The research objectives aim at establishing the RC's clinical significance over LC. It also analyzes the factors that inform patients' decisions regarding their preferred cholecystitis management procedure. A literature review of the current scholarly information on the subject was conducted to gather insights that somehow informed the study. The researchers employed a descriptive and explanatory research design based on mixed methods (quantitative and qualitative ones). Besides, the target population for this study was selected from Memorial Hermann Hospital in Houston, Texas. Although the scholars had projected a 292 sample size based on the Yamane formula, they gathered 350 voluntary participants comprising 250 cholecystitis patients and 100 surgical unit healthcare professionals. The data collection tools included surveys and interviews. The collected information was analyzed using MS Excel and SPSS statistical tools. The findings showed that cholecystitis patients analyzed factors such as the degree of pain, cost, postoperative complications, operation duration, scarring, and recuperation rate before making decisions. RC proved to have more benefits than LC. However, LC was still preferred in some cases because it is cheaper and takes less surgical time. 

The preoperative prediction of a difficult laparoscopic cholecystectomy

INTRODUCTION: Laparoscopic cholecystectomy has become the standard operative procedure for cholelithiasis, but there are still some patients requiring conversion to open cholecystectomy mainly because of technical difficulty. The aim was to define the possibility of prediction of a difficult outcome preoperatively. AIMS AND OBJECTIVES: 1. To determine the possibility of predicting preoperatively a difficult laparoscopic cholecystectomy. 2. To determine the factors which significantly predict the outcome. 3. To identify patients at risk in an elective setting and thereby enable patient counselling. MATERIALS AND METHODOLOGY: 40 patients with symptomatic gallstones planned for elective surgery and operated upon by a single experienced laparoscopic surgeon were studied by assigning a score depending upon clinical and sonological parameters. RESULTS: Out of 40 cases, 11 had a difficult outcome with scores ranging between 5 and 10. None had a score >10. Age >50, Obesity, Previous hospitalization, Palpable gallbladder and Wall thickness > 4mm on ultrasonogram were found to significantly influence the outcome. The ideal cut off point was a score of 3, which could predict difficulty. Overall the positive predictive value was 78.57%. CONCLUSION: A difficult laparoscopic cholecystectomy can be predicted preoperatively. Patients having high risk may be informed and scheduled appropriately. An experienced surgeon has to operate on these patients, and he or she has to make an early decision to convert in case of difficulty

Diseases of the Abdomen and Pelvis 2018-2021: Diagnostic Imaging - IDKD Book

Gastrointestinal disease; PET/CT; Radiology; X-ray; IDKD; Davo

Artificial intelligence in gastroenterology: a state-of-the-art review

The development of artificial intelligence (AI) has increased dramatically in the last 20 years, with clinical applications progressively being explored for most of the medical specialties. The field of gastroenterology and hepatology, substantially reliant on vast amounts of imaging studies, is not an exception. The clinical applications of AI systems in this field include the identification of premalignant or malignant lesions (e.g., identification of dysplasia or esophageal adenocarcinoma in Barrett's esophagus, pancreatic malignancies), detection of lesions (e.g., polyp identification and classification, small-bowel bleeding lesion on capsule endoscopy, pancreatic cystic lesions), development of objective scoring systems for risk stratification, predicting disease prognosis or treatment response [e.g., determining survival in patients post-resection of hepatocellular carcinoma), determining which patients with inflammatory bowel disease (IBD) will benefit from biologic therapy], or evaluation of metrics such as bowel preparation score or quality of endoscopic examination. The objective of this comprehensive review is to analyze the available AI-related studies pertaining to the entirety of the gastrointestinal tract, including the upper, middle and lower tracts; IBD; the hepatobiliary system; and the pancreas, discussing the findings and clinical applications, as well as outlining the current limitations and future directions in this field.Cellular mechanisms in basic and clinical gastroenterology and hepatolog

Incidental Findings Found In Typical Screening Populations Undergoing Colorectal Cancer Screening with Computed Tomography Colonography: A Systematic Review

Background: CT colonography (CTC) is a noninvasive technology used to screen for colorectal cancer. Unlike other screening modalities, CTC provides a view of the abdomen and pelvis allowing radiologists to detect lesions in extracolonic organs. There is much debate on the balance of potential benefits versus potential harms of discovering, working up and treating these extracolonic findings. This debate might be especially relevant for asymptomatic populations receiving screening with CTC. Purpose: This systematic review aims to determine the frequency and clinical implications of finding incidental, extracolonic lesions during CT colonography (CT) in asymptomatic, screening populations. In addition, this review reports the frequency and clinical outcomes of clinically important lesions. Lastly, this review summarizes the various methods studies used to define the clinical significance of incidental findings. Data Sources: I carried out a systematic search of MEDLINE, Embase, the Cochrane Clinical Trials databases and published reviews up to March 2012. Study Selection: Two investigators independently reviewed 282 abstracts and 53 full text articles using a set of predefined inclusion and exclusion criteria. Both reviewers carried out independent critical appraisals of each study using criteria developed by the United States Preventive Services Task Force. Data Extraction: One reviewer extracted information on study samples, designs, populations, interventions and outcomes from six studies. A second reviewer verified this information for accuracy. Data Synthesis: The frequency of extracolonic findings (ECFs) ranged from 27.2% to 68.9% (mean 49.3%). Included studies used similar classification systems of clinical importance, which were primarily based on the likelihood of clinical workup. Studies reported that 5.6% of the reported ECFs were of high clinical importance and 15.5% of lesions were either moderate- or high-importance. A minority of these findings represented lesions that could have benefitted from early diagnosis and intervention. Studies reported that 0.09% to 1.2% of subjects were diagnosed with AAAs and 0.23% to 0.88% were diagnosed with extracolonic cancers. Studies used widely varying lengths and methods of following ECFs, making it difficult to estimate the true clinical implications of incidental findings. However, the range of moderate/high to high-importance findings (5.6% to 15.5%) provides a good estimate of the number of subjects requiring some clinical workup. Limitations: I identified several weaknesses of the available literature on ECFs from screening CTC. For instance, many included studies suffered from poor follow-up and incomplete reporting of outcomes. In addition, no studies properly addressed the potential physical and psychological harms of being diagnosed, worked up and treated for extracolonic findings. Lastly, the included literature does not address how ECFs are handled in non-academic settings. This systematic review also had several weaknesses. The decision to limit the review to screening populations might reduce the strength of my findings. I attempted to compensate by including populations at high risk of CRC and studies conducted outside the US, but this might have reduced the generalizability of my findings. Furthermore, I were unable to adjust for different follow-up time periods, making it difficult to compare the clinical outcomes of ECFs among included studies. Lastly, I attempted to develop an outcomes table for ECFs from screening CTC, but were unable to do so because of the imprecision of results, variable periods of follow-up and gaps in reported outcomes. Conclusions: Based on these results, a large proportion of individuals receiving CT colonography for colorectal cancer screening will have an extracolonic lesion discovered. Roughly one-fifth to one-third of these findings will receive some clinical workup and the majority of these will ultimately be diagnosed as benign. Since a small percentage of potentially important findings will result in clinical benefit, it is possible that the classification systems are overly sensitive. In addition, the reporting of all extracolonic findings might result in unnecessary testing and patient anxiety. Unfortunately, the existing data does not provide enough certainty to know which lesions can go unreported without putting the patient at harm. However, based on the evidence, it appears that most radiologists and primary care physicians err on the side of reporting findings, which also results in unnecessary harms to patients. Another source of unnecessary and potentially harmful care is the large variability in radiologist interpretation of extracolonic findings. Based on this review, there are no indications that the development of a standardized classification system of ECFs has successfully reduced this variation. There are two primary ways to improve this practice variability in the future. First, classification systems could be improved to provide more guidance, especially for findings that have an uncertain balance of benefits and harms. More primary research might be required before this is possible. Second, training programs for CTC should require specific training for interpreting ECFs, including the proper follow-up of specific findings.Master of Public Healt