Endoscopic ultrasonography for gastric submucosal lesions

Gastric submucosal tumors(SMTs) are a rather frequent finding,occurring in about 0.36%of routine upper GIendoscopies.Endoscopic ultrasonography(EUS) has emerged as a reliable investigative procedure for evaluation of these lesions.Diagnostic EUS has the ability to differentiate intramural tumors from extraluminal compressions and can also show the layer of origin of gastric SMTs.Tumors can be further characterized by their layer of origin,echo pattern and margin.EUS-risk criteria of their malignant potential are presented,although the emergence of EUS-FNA has opened new indications for transmural tissue diagnosis and expanded the possibilities of EUS in SMTs of the stomach.Tissue diagnosis should address whether the SMT is a Gastrointestinal stromal tumour(GIST) or another tumor type and evaluate the malignant potential of a given GIST.However,there seems to be a lack of data on the optimal strategy in SMTs suspected to be GISTs with a negative EUS-FNA tissue diagnosis.The current management strategies,as well as open questions regarding their treatment are also presented.

Gut microbiota and non-alcoholic fatty liver disease

BACKGROUND： Non-alcoholic fatty liver disease （NAFLD） is a common disorder with poorly understood pathogenesis. Beyond environmental and genetic factors, cumulative data support the causative role of gut microbiota in disease development and progression.

Gene polymorphisms associated with functional dyspepsia

Functional dyspepsia(FD) is a constellation of functional upper abdominal complaints with poorly elucidated pathophysiology. However, there is increasing evidence that susceptibility to FD is influenced by hereditary factors. Genetic association studies in FD have examined genotypes related to gastrointestinal motility or sensation, as well as those related to inflammation or immune response. G-protein b3 subunit gene polymorphisms were first reported as being associated with FD. Thereafter, several gene polymorphisms including serotonin transporter promoter, interlukin-17 F, migration inhibitory factor, cholecystocynine-1 intron 1, cyclooxygenase-1, catechol-o-methyltransferase, transient receptor potential vanilloid 1 receptor, regulated upon activation normal T cell expressed and secreted, p22 PHOX, Toll like receptor 2, SCN10 A, CD14 and adrenoreceptors have been investigated in relation to FD; however, the results are contradictory. Several limitations underscore the value of current studies. Among others, inconsistencies in the definitions of FD and controls, subject composition differences regarding FD subtypes, inadequate samples, geographical and ethnical differences, as well as unadjusted environmental factors. Further well-designed studies are necessary to determine how targeted genes polymorphisms, influence the clinical manifestations and potentially the therapeutic response in FD.

Virtual reality simulators for gastrointestinal endoscopy training

The use of simulators as educational tools for medical procedures is spreading rapidly and many efforts have been made for their implementation in gastrointestinal endoscopy training. Endoscopy simulation training has been suggested for ascertaining patient safety while positively influencing the trainees' learning curve. Virtual simulators are the most promising tool among all available types of simulators. These integrated modalities offer a human-like endoscopy experience by combining virtual images of the gastrointestinal tract and haptic realism with using a customized endoscope. From their first steps in the 1980s until today, research involving virtual endoscopic simulators can be divided in two categories: investigation of the impact of virtual simulator training in acquiring endoscopy skills and measuring competence. Emphasis should also be given to the financial impact of their implementation in endoscopy, including the cost of these state-of-theart simulators and the potential economic benefits from their usage. Advances in technology will contribute to the upgrade of existing models and the development of new ones; while further research should be carried out to discover new fields of application.

Insulin action in muscle and adipose tissue in type 2 diabetes:The significance of blood flow

Under normal metabolic conditions insulin stimulates microvascular perfusion(capillary recruitment) of skeletal muscle and subcutaneous adipose tissue and thus increases blood flow mainly after meal ingestion or physical exercise.This helps the delivery of insulinitself but also that of substrates and of other signalling molecules to multiple tissues beds and facilitates glucose disposal and lipid kinetics.This effect is impaired in insulin resistance and type 2 diabetes early in the development of metabolic dysregulation and reflects early-onset endothelial dysfunction.Failure of insulin to increase muscle and adipose tissue blood flow results in decreased glucose handling.In fat depots,a blunted postprandial blood flow response will result in an insufficient suppression of lipolysis and an increased spill over of fatty acids in the circulation,leading to a more pronounced insulin resistant state in skeletal muscle.This defect in blood flow response is apparent even in the prediabetic state,implying that it is a facet of insulin resistance and exists long before overt hyperglycaemia develops.The following review intends to summarize the contribution of blood flow impairment to the development of the atherogenic dysglycemia and dyslipidaemia.

Endoscopic treatments for chronic radiation proctitis

Chronic radiation proctitis is a complication that occurs in patients who receive radiation therapy for pelvic malignancies. The common presentation is with rectal bleeding, but also rectal pain, diarrhea, tenesmus and even passage of mucus can occur. The optimal treatment of bleeding due to radiation proctitis remains unclear. Among various therapeutic options, medical management is generally ineffective and surgical intervention has a high incidence of morbidity. Promising advances have been made in endoscopic therapy, including argon plasma coagulation (APC), formalin application as well as new techniques such as radio-frequency ablation and cryoablation. APC is a safe, highly effective and long-lasting therapy in patients with rectal bleeding associated with radiation proctitis. It has been shown that several sessions of APC reduce the rate of bleeding and therefore the blood transfusion requirements. Moreover, the effect of treatment is long lasting. However, best results are achieved in patients with mild to moderate radiation proctitis, leaving space for alternative treatments for patients with more severe disease. In patients with severe or refractoryradiation proctitis intra rectal formalin application is an appropriate treatment option. Radiofrequency ablation and cryoablation have shown efficacy as alternative methods in a limited number of patients with refractory chronic radiation proctitis.

Two cameras detect more lesions in the small-bowel than one

AIM:To explore the feasibility of dual camera capsule (DCC)small-bowel(SB)imaging and to examine if two cameras complement each other to detect more SB lesions.METHODS:Forty-one eligible,consecutive patients underwent DCC SB imaging.Two experienced investigators examined the videos and compared the total number of detected lesions to the number of lesions detected by each camera separately.Examination tolerability was assessed using a questionnaire.RESULTS:One patient was excluded.DCC cameras detected 68 positive findings(POS)in 20(50%)cases.Fifty of them were detected by the"yellow"camera,48 by the"green"and 28 by both cameras;44%(n=22)of the"yellow"camera’s POS were not detected by the"green"camera and 42%(n=20)of the"green" camera’s POS were not detected by the"yellow"camera.In two cases,only one camera detected significant findings.All participants had 216 findings of unknown significance(FUS).The"yellow","green"and both cameras detected 171,161,and 116 FUS,respectively;32%(n=55)of the"yellow"camera’s FUS were not detected by the"green"camera and 28%(n=45)of the"green"camera’s FUS were not detected by the "yellow"camera.There were no complications related to the examination,and 97.6%of the patients would repeat the examination,if necessary.CONCLUSION:DCC SB examination is feasible and well tolerated.The two cameras complement each other to detect more SB lesions.

Colonoscopy attachments for the detection of precancerous lesions during colonoscopy:A review of the literature

Although colonoscopy has been proven effective in reducing the incidence of colorectal cancer through the detection and removal of precancerous lesions, it remains an imperfect examination, as it can fail in detecting up to almost one fourth of existing adenomas. Among reasons accounting for such failures, is the inability to meticulously visualize the colonic mucosa located either proximal to haustral folds or anatomic curves, including the hepatic and splenic flexures. In order to overcome these limitations, various colonoscope attachments aiming to improve mucosal visualization have been developed. All of them-transparent cap, Endocuff, Endocuff Vision and Endorings-are simply mounted onto the distal tip of the scope. In this review article, we introduce the rationale of their development, present their mode of action and discuss in detail the effect of their implementation in the detection of lesions during colonoscopy.

Omeprazole maintenance therapy prevents recurrent ulcer bleeding after surgery for duodenal ulcer

瞄准：与周期性的溃疡为十二指肠溃疡在外科以后流血在病人评估 omeprazole 维护治疗。方法：我们与周期性的溃疡为十二指肠溃疡在外科以后流血学习了 15 个连续病人。维护治疗在溃疡愈合以后被给的 Omeprazole (20 mg/d ) 。除了临床的后续，回廊 24-h 胃的 pH 试金与以前的十二指肠溃疡外科而是没有溃疡复发在那些病人和控制被执行在前并且在 omeprazole 治疗期间。结果：所有 15 溃疡在为 2 瞬间与 omeprazole (40 mg/d ) 被对待以后被愈合。有二的十一个病人(1-9 ) 周期性的溃疡流血的事件完成了后续(43， 12-72 瞬间) 。任何一个都没他们有一个流血事件当时在 omeprazole 上。一个病人中止了治疗并且有周期性的流血。在病人的胃的 pH【4 的中部的 24-h 部分时间是 80， 46-95% ，并且被归结为 32，由 omeprazole (P=0.002 ) 的 13-70% 。结论：有 omeprazole (20 mg/day ) 的长期的维护治疗在阻止周期性的溃疡流血是有效的。

Improved bowel preparation increases polyp detection and unmasks significant polyp miss rate

AIM: To retrospectively compare previous-day vs splitdose preparation in terms of bowel cleanliness and polyp detection in patients referred for polypectomy. METHODS: Fifty patients underwent two colonoscopies: one diagnostic in a private clinic and a second for polypectomy in a University Hospital. The latter procedures were performed within 12 wk of the index ones. Examinations were accomplished by two experienced endoscopists, different in each facility. Twenty-seven patients underwent screening/surveillance colonoscopy, while the rest were symptomatic. Previous day bowel preparation was utilized initially and splitdose for polypectomy. Colon cleansing was evaluated using the Aronchick scale. We measured the number of detected polyps, and the polyp miss rates per-polyp.RESULTS: Excellent/good preparation was reported in 38 cases with previous-day preparation(76%) vs 46 with split-dose(92%), respectively(P = 0.03). One hundred and twenty-six polyps were detected initially and 169 subsequently(P < 0.0001); 88 vs 126 polyps were diminutive(P < 0.0001), 25 vs 29 small(P = 0.048) and 13 vs 14 equal or larger than 10 mm. The miss rates for total, diminutive, small and large polyps were 25.4%, 30.1%, 13.7% and 6.6%, respectively. Multivariate analysis revealed that split-dose preparation was significantly associated(OR, P) with increased number of polyps detected overall(0.869, P < 0.001), in the right(0.418, P = 0.008) and in the left colon(0.452, P = 0.02). CONCLUSION: Split-dose preparation improved colon cleansing, enhanced polyp detection and unmasked significant polyp miss rates.

Role of pancreatic endoscopic ultrasonography in 2010

Endoscopic ultrasonography (EUS) was introduced 25 years ago aiming at better visualization of the pancreas compared to transabdominal ultrasonography. This update discusses the current evidence in 2010 concerning the role of EUS in the clinical management of patients with pancreatic disease. Major indications of EUS are:(1) Detection of common bile duct stones (e.g. in acute pancreatitis); (2) Detection of small exo-and endocrine pancreatic tumours; and (3) Performance of fine needle aspiration in pancreatic masses depending on therapeutic consequences. EUS seems to be less useful in cases of chronic pancreatitis and cystic pan-creatic lesions. Moreover the constant improvement of computed tomography has limited the role of EUS in pancreatic cancer staging. On the other hand,new therapeutic options are available due to EUS,such as pancreatic cyst drainage and celiac plexus neurolysis,offering a new field in which new techniques may arise. So the main goal of this review is to determine the exact role of EUS in a number of pancreatic and biliary diseases.

Sedation-risk-free colonoscopy for minimizing the burden of colorectal cancer screening

Unsedated colonoscopy is available worldwide,but is not a routine option in the United States(US).We conducted a literature review supplemented by our experience and expert commentaries to provide data to support the use of unsedated colonoscopy for colorectal cancer screening.Medline data from 1966 to 2009 were searched to identify relevant articles on the subject.Data were summarized and co-authors provided critiques as well as accounts of unsedated colonoscopy for screening and surveillance.Diagnostic colonoscopy was initially dev eloped as an unsedated procedure.Procedure-re lated discomfort led to wide adoption of sedation in the US,although unsedated colonoscopy remains the usual practice elsewhere.The increased use of colonoscopy for colorectal cancer screening in healthy,asymptomatic individuals suggests a reass-essment of the burden of sedation in colonoscopy for screening is appropriate in the US for lowering costs and minimizing complications for patients.A water method developed to minimize discomfort has shown promise to enhance outcomes of unsedated colonoscopy.The use of scheduled,unsedated colono scopy in the US appears to be feasible for colorectal cancer screening.Studies to assess its applicability in diverse practice settings deserve to be conducted and supported.

Effect of Endocuff use on colonoscopy outcomes: A systematic review and meta-analysis

BACKGROUND Endocuff-a plastic device with flexible projections-mounted on the distal tip of the colonoscope, promises improved colonic mucosa inspection.AIM To elucidate the effect of Endocuff on adenoma detection rate(ADR), advanced ADR(AADR) and mean number of adenomas per colonoscopy(MAC).METHODS Literature searches identified randomized-controlled trials evaluating Endocuffassisted colonoscopy(EAC) vs conventional colonoscopy(CC) in terms of ADR,AADR and MAC. The effect size on study outcomes was calculated using fixed or random effect model, as appropriate, and it is shown as relative risk(RR) [95%confidence interval(CI)] and mean difference(MD)(95%CI). The rate of device removal in EAC arms was also calculated.RESULTS We identified nine studies enrolling 6038 patients. All studies included mixed population(screening, surveillance and diagnostic examinations). Seven and two studies evaluated the first and the second-generation device, respectively. EAC was associated with increased ADR compared to CC [RR(95%CI): 1.18(1.05-1.32); Ι~2 = 71%]; EAC benefits more endoscopists with ADR ≤ 35% compared to those with ADR > 35% [RR(95%CI): 1.37(1.08-1.74); Ι~2 = 49% vs 1.10(0.99-1.24); Ι~2= 71%]. In terms of AADR and MAC, no difference was detected between EAC and CC [RR(95%CI): 1.03(0.85-1.25); Ι~2 = 15% and MD(95%CI): 0.30(-0.17-0.78);Ι~2 = 99%]. Subgroup analysis did not show any difference between the two device generations regarding all three endpoints. In EAC arms, the device had to be removed in 3%(95%CI: 2%-5%) of the cases mainly due to tortuous sigmoid or presence of diverticula along it.CONCLUSION EAC increases ADR compared to CC, especially for endoscopists with lower ADR. On the other hand, no significant effect on AADR and MAC was detected.

Can we improve the diagnostic yield of small bowel video-capsule endoscopy?

Video-capsule endoscopy has revolutionized the examination of small bowel mucosa.However,this modality is relatively young and its diagnostic yield is low.Herein,we discuss different approaches to improve examination's diagnostic yield.There are strong data supporting some of them while there is speculation about the rest.As capsule endoscopy continues to evolve there is also a strong belief that technology will overcome at least some of the obst acles that hamper capsule endoscopy's diagnostic yield sometime in the near future.

Artificial intelligence-aided colonoscopy:Recent developments and future perspectives

Artificial intelligence(AI)systems,especially after the successful application of Convolutional Neural Networks,are revolutionizing modern medicine.Gastrointestinal Endoscopy has shown to be a fertile terrain for the development of AI systems aiming to aid endoscopists in various aspects of their daily activity.Lesion detection can be one of the two main aspects in which AI can increase diagnostic yield and abilities of endoscopists.In colonoscopy,it is well known that a substantial rate of missed neoplasia is still present,representing the major cause of interval cancer.In addition,an extremely high variability in adenoma detection rate,the main key quality indicator in colonoscopy,has been extensively reported.The other domain in which AI is believed to have a considerable impact on everyday clinical practice is lesion characterization and aid in“optical diagnosis”.By predicting in vivo histology,such pathology costs may be averted by the implementation of two separate but synergistic strategies,namely the“leave-in-situ”strategy for<5 mm hyperplastic lesions in the rectosigmoid tract,and“resect and discard”for the other diminutive lesions.In this opinion review we present current available evidence regarding the role of AI in improving lesions’detection and characterization during colonoscopy.

An unusual case of prolonged post-endoscopic retrograde cholangiopancreatography jaundice

Despite the effectiveness of endoscopic retrograde cholangiopancreatography（ERCP） for the treatment of choledocholithiasis, various complications have been described. We herein report the first case of prolonged postERCP jaundice due to toxicity of the contrast agent Iobitridol（~174;XENETIX, Guerbet, Roissy Cd G Cedex, France） in a patient who underwent ERCP with sphincterectomy and common bile duct stone removal. While clinical improvement and normalization of aminotransferases and cholestatic enzymes after the procedure, an unexplained increase of direct bilirubin was noticed. A second ERCP was performed one week later, excluding possible remaining choledocholithiasis. Nevertheless, serum direct bilirubin increased further up to 15 mg/d L. Other potential causes of direct hyperbilirubinemia were ruled out and patient＇s liver biopsy was compatible with drug-induced liver toxicity. Additionally, the cause-result time connection between the use of Iobitridol and bilirubin increase indicated the possibility of a toxic effect related to the repeated use of the particular contrast agent. Iobitridol, a contrast agent, can induce prolonged direct hyperbilirubinemia.

屏蔽的 colorectal 癌症上的希腊医学院的学生的了解和态度

AIM: To prospectively assess the knowledge and attitudes of medical students (MS), as tomorrow’s physicians, about colorectal cancer (CRC) and its screening modalities.METHODS: Three hundred fourth year MS of the University of Athens were enrolled in this survey. Their selection was random, based on student identification card number. All participants completed an anonymous written questionnaire over a 4 month period. The questionnaire was divided into 4 sections and included queries about CRC-related symptoms, screening with colonoscopy and MS awareness and attitudes in this field. Following collection and analysis of the data, the results are presented as percentages of answers for each separate question. RESULTS: Two hundred and sixty-five students an-swered the questionnaire over a 4 mo period. Interestingly, only 69% of the study population considered CRC to be a high-risk condition for public health. However, the vast majority of participants identified CRC-related symptoms and acknowledged its screening to be of great value in reducing CRC incidence and mortality. A very small proportion (38%) had received information material regarding CRC screening (either during their medical training or as a part of information provided to the general public) and only 60% of the participants declared willingness to receive further information. Regarding colonoscopy, 85% would prefer an alternative to colonoscopy methods for CRC screening. Moreover, 53% considered it to be a painful method and 68% would appreciate more information about the examination.CONCLUSION: MS in Greece need to be better informed about CRC screening and screening colonoscopy.

Academic hospital staff compliance with a fecal immunochemical test-based colorectal cancer screening program

AIM: To measure the compliance of an Academic Hospital staff with a colorectal cancer(CRC) screening program using fecal immunochemical test(FIT).METHODS: All employees of 'Attikon' University General Hospital aged over 50 years were thoroughly informed by a team of physicians and medical students about the study aims and they were invited to undergo CRC screening using two rounds of FIT(DyoniFOB~ Combo H, DyonMed SA, Athens, Greece). The tests were provided for free and subjects tested positive were subsequently referred for colonoscopy. One year after completing the two rounds, participants were asked to be re-screened by means of the same test.RESULTS: Among our target population consisted of 211 employees, 59(27.9%) consented to participate, but only 41(19.4%) and 24(11.4%) completed the first and the second FIT round, respectively. Female gender was significantly associated with higher initial participation(P = 0.005) and test completion- first and second round-(P = 0.004 and P = 0.05) rates, respectively. Phy sician’s(13.5% vs 70.2%, P < 0.0001) participation and test completion rates(7.5% vs 57.6%, P < 0.0001 for the first and 2.3% vs 34%, P < 0.0001 for the second round) were significantly lower compared to those of the administrative/technical staff. Similarly, nurses participated(25.8% vs 70.2%, P = 0.0002) and completed the first test round(19.3% vs 57.6%, P = 0.004) in a significant lower rate than the administrative/technical staff. One test proved false positive. No participant repeated the test one year later.CONCLUSION: Despite the well-organized, guided and supervised provision of the service, the compliance of the Academic Hospital personnel with a FIT-based CRC screening program was suboptimal, especially among physicians.

Is there a role for colon capsule endoscopy beyond colorectal cancer screening? A literature review

Colon capsule endoscopy is recommended in Europe alternatively to colonoscopy for colorectal cancer screening in average risk individuals. The procedure has also been proposed to complete colon examination in cases of incomplete colonoscopy or when colonoscopy is contraindicated or refused by the patient. As tissue samples cannot be obtained with the current capsule device, colon capsule endoscopy has no place in diagnosing ulcerative colitis or in dysplasia surveillance. Nevertheless, data are accumulating regarding its feasibility to examine ulcerative colitis disease extent and to monitor disease activity and mucosal healing, even though reported results on the capsule's performance in this field vary greatly. In this review we present the currently available evidence for the use of colon capsule endoscopy to complement colonoscopy failure to reach the cecum and its use to evaluate ulcerative colitis disease activity and extent. Moreover, we provide an outlook on issues requiring further investigation before the capsule becomes a mainstream alternative to colonoscopy in such cases.

New endoscopes and add-on devices to improve colonoscopy performance

Colonoscopy is the gold standard for colorectal cancer prevention; however, it is still an imperfect modality. Precancerous lesions can be lost during screening examinations, thus increasing the risk of interval cancer. A variety of factors either patient-, or endoscopist dependent or even the procedure itself may contribute to loss of lesions. Sophisticated modalities including advanced technology endoscopes and add-on devices have been developed in an effort to eliminate colonoscopy's drawbacks and maximize its ability to detect potentially culprit polyps. Novel colonoscopes aim to widen the field of view. They incorporate more than one cameras enabling simultaneous image transmission. In that way the field of view can expand up to 330°. On the other hand a plethora of add-on devices attachable on the standard colonoscope promise to detect lesions in the proximal aspect of colonic folds either by offering a retrograde view of the lumen or by straightening the haustral folds during withdrawal. In this minireview we discuss how these recent advances affect colonoscopy performance by improving its quality indicators(cecal intubation rate, adenoma detection rate) and other metrics(polyp detection rate, adenomas per colonoscopy, polyp/adenoma miss rate) associated with examination's outcomes.