Risk factors for small bowel angioectasia:The impact of visceral fat accumulation

AIM: To investigate visceral fat accumulation in association with the risk of small bowel angioectasia.METHODS: We retrospectively investigated 198 consecutive patients who underwent both capsule endoscopy and CT for investigation of obscure gastrointestinal bleeding(OGIB) from January 2009 to September 2013. The visceral fat area(VFA) and subcutaneous fat area were measured by CT, and information on comorbidities, body mass index, and medications was obtained from their medical records.Logistic regression analysis was used to evaluate associations.RESULTS: Capsule endoscopy revealed small bowel angioectasia in 18/198(9.1%) patients with OGIB.Compared to patients without small bowel angioectasia,those with small bowel angioectasia had a significantly higher VFA(96 ± 76.0 cm2 vs 63.4 ±51.5 cm2, P = 0.016) and a higher prevalence of liver cirrhosis(61% vs 22%, P < 0.001). The proportion of patients with chronic renal failure was higher in patients with small bowel angioectasia(22% vs 9%,P = 0.11). There were no significant differences in subcutaneous fat area or waist circumference. The prevalence of small bowel angioectasia progressively increased according to the VFA. Multivariate analysis showed that the VFA [odd ratio(OR) for each 10-cm2 increment = 1.1; [95% confidence interval(CI):1.02-1.19; P = 0.021] and liver cirrhosis(OR = 6.1,95%CI: 2.2-18.5; P < 0.001) were significant risk factors for small bowel angioectasia.CONCLUSION: VFA is positively associated with theprevalence of small bowel angioectasia, for which VFA and liver cirrhosis are independent risk factors in patients with OGIB.

Detection of Angioectasias and Haemorrhages Incorporated into a Multi-Class Classification Tool for the GI Tract Anomalies by Using Binary CNNs

The proposed deep learning algorithm will be integrated as a binary classifier under the umbrella of a multi-class classification tool to facilitate the automated detection of non-healthy deformities, anatomical landmarks, pathological findings, other anomalies and normal cases, by examining medical endoscopic images of GI tract. Each binary classifier is trained to detect one specific non-healthy condition. The algorithm analyzed in the present work expands the ability of detection of this tool by classifying GI tract image snapshots into two classes, depicting haemorrhage and non-haemorrhage state. The proposed algorithm is the result of the collaboration between interdisciplinary specialists on AI and Data Analysis, Computer Vision, Gastroenterologists of four University Gastroenterology Departments of Greek Medical Schools. The data used are 195 videos (177 from non-healthy cases and 18 from healthy cases) videos captured from the PillCam(R) Medronics device, originated from 195 patients, all diagnosed with different forms of angioectasia, haemorrhages and other diseases from different sites of the gastrointestinal (GI), mainly including difficult cases of diagnosis. Our AI algorithm is based on convolutional neural network (CNN) trained on annotated images at image level, using a semantic tag indicating whether the image contains angioectasia and haemorrhage traces or not. At least 22 CNN architectures were created and evaluated some of which pre-trained applying transfer learning on ImageNet data. All the CNN variations were introduced, trained to a prevalence dataset of 50%, and evaluated of unseen data. On test data, the best results were obtained from our CNN architectures which do not utilize backbone of transfer learning. Across a balanced dataset from no-healthy images and healthy images from 39 videos from different patients, identified correct diagnosis with sensitivity 90%, specificity 92%, precision 91.8%, FPR 8%, FNR 10%. Besides, we compared the performance of our best CNN algorithm versus our same goal algorithm based on HSV colorimetric lesions features extracted of pixel-level annotations, both algorithms trained and tested on the same data. It is evaluated that the CNN trained on image level annotated images, is 9% less sensitive, achieves 2.6% less precision, 1.2% less FPR, and 7% less FNR, than that based on HSV filters, extracted from on pixel-level annotated training data.

Distribution of bleeding gastrointestinal angioectasias in a Western population

AIM:To define which segments of the gastrointestinal tract are most likely to yield angioectasias for ablative therapy. METHODS:A retrospective chart review was performed for patients treated in the Louisiana State University Health Sciences Center Gastroenterology clinics between the dates of July 1, 2007 and October 1, 2010. The selection of cases for review was initiated by use of our electronic medical record to identify all patients with a diagnosis of angioectasia, angiodysplasia, or arteriovenous malformation. Of these cases, chart reviews identified patients who had a complete evaluation of their gastrointestinal tract as defined by at least one upper endoscopy, colonoscopy and small bowel capsule endoscopy within the past three years. Patients without evidence of overt gastrointestinal bleeding or iron deficiency anemia associated with intestinal angioectasias were classified as asymptomatic and excluded from this analysis. Thirty-five patients with confirmed, bleeding intestinal angioectasias who had undergone complete endoscopic evaluation of the gastrointestinal tract were included in the final analysis. RESULTS:A total of 127 cases were reviewed. Sixtysix were excluded during subsequent screening due to lack of complete small bowel evaluation and/or lack of documentation of overt bleeding or iron deficiency anemia. The 61 remaining cases were carefully examined with independent review of endoscopic images as well as complete capsule endoscopy videos. This anal- ysis excluded 26 additional cases due to insufficient records/images for review, incomplete capsule examination, poor capsule visualization or lack of confirmation of typical angioectasias by the principal investigator on independent review. Thirty-five cases met criteria for final analysis. All study patients were age 50 years or older and 13 patients (37.1%) had chronic kidney disease stage 3 or higher. Twenty of 35 patients were taking aspirin (81 mg or 325 mg), clopidogrel, and/or warfarin, with 8/20 on combination therapy. The number and location of angioectasis was documented for each case. Lesions were then classified into the following segments of the gastrointestinal tract:esophagus, stomach, duodenum, jejunum, ileum, right colon and left colon. The location of lesions within the small bowel observed by capsule endoscopy was generally defined by percentage of total small bowel transit time with times of 0%-9%, 10%-39%, and 40%-100% corresponding to the duodenum, jejunum and ileum, respectively. Independent review of complete capsule studies allowed for deviation from this guideline if capsule passage was delayed in one or more segments. In addition, the location and number of angioectasias observed in the small bowel was further modified or confirmed by subsequent device-assisted enteroscopy (DAE) performed in the 83% of cases. In our study population, angioectasias were most commonly found in the jejunum (80%) followed by the duodenum (51%), stomach (22.8%), and right colon (11.4%). Only two patients were found to have angioectasias in the ileum (5.7%). Twenty-one patients (60%) had angioectasias in more than one location.CONCLUSION:Patients being considered for endoscopic ablation of symptomatic angioectasias should undergo push enteroscopy or anterograde DAE and reinspection of the right colon.

胶囊内镜检查在老年患者中的应用

目的探讨胶囊内镜检查在老年患者中的应用特点和安全性。方法收集2002年5月-2007年9月接受胶囊内镜检查的376例患者的临床资料,并根据年龄分为老年组(≥60岁,n=134)和对照组(<60岁,n=242)。比较两组的胶囊内镜检查情况,包括消化道转运时间、小肠检查完成率和检查中临床问题的发生情况;分析老年组胶囊内镜的检查结果。结果与对照组比较,老年组小肠转运时间明显延长,为(309.54±99.92)min vs(260.21±99.26)min(P=0.0003);小肠检查完成率明显降低,为58.2%vs 72.3%(P=0.00596)。老年组检查过程中临床问题明显高于对照组(38.1%vs 27.7%)(P=0.048),其中以胶囊滞留食管最为常见。老年组纳入诊断率统计的128例中有71例获阳性诊断(55.5%),其中42例为血管发育异常。结论老年患者胶囊内镜检查安全性较好,具有小肠转运时间相对延长、胶囊易滞留于食管、全小肠检查完成率相对较低以及血管病变是其最常见结果等特点。

Diagnostic and therapeutic challenges of gastrointestinal angiodysplasias: A critical review and view points

Gastrointestinal angiodysplasias (GIADs), also called angioectasias, are the most frequent vascular lesions. Its precise prevalence is unknown since most of them are asymptomatic. However, the incidence may be increasing since GIADs affect individuals aged more than 60 years and population life expectancy is globally increasing worldwide. They are responsible of about 5% to 10% of all gastrointestinal bleeding (GIB) cases. Most GIADs are placed in small bowel, where are the cause of 50 to 60% of obscure GIB diagnosed with video capsule endoscopy. They may be the cause of fatal severe bleeding episodes;nevertheless, recurrent overt or occult bleeding episodes requiring repeated expensive treatments and disturbing patient’s quality-of-life are more frequently observed. Diagnosis and treatment of GIADs (particularly those placed in small bowel) are a great challenge due to insidious disease behavior, inaccessibility to affected sites and limitations of available diagnostic procedures. Hemorrhagic causality out of the actively bleeding lesions detected by diagnostic procedures may be difficult to establish. No treatment guidelines are currently available, so there is a high variability in the management of these patients. In this review, the epidemiology and pathophysiology of GIADs and the status in the diagnosis and treatment, with special emphasis on small bowel angiodysplasias based on multiple publications, are critically discussed. In addition, a classification of GIADs based on their endoscopic characteristics is proposed. Finally, some aspects that need to be clarified in future research studies are highlighted.

Diagnosis and therapeutic strategies for small bowel vascular lesions

Small bowel vascular lesions, including angioectasia (AE), Dieulafoy’s lesion (DL) and arteriovenous malformation (AVM), are the most common causes of obscure gastrointestinal bleeding. Since AE are considered to be venous lesions, they usually manifest as a chronic, well-compensated condition. Subsequent to video capsule endoscopy, deep enteroscopy can be applied to control active bleeding or to improve anemia necessitating blood transfusion. Despite the initial treatment efficacy of argon plasma coagulation (APC), many patients experience re-bleeding, probably because of recurrent or missed AEs. Pharmacological treatments can be considered for patients who have not responded well to other types of treatment or in whom endoscopy is contraindicated. Meanwhile, a conservative approach with iron supplementation remains an option for patients with mild anemia. DL and AVM are considered to be arterial lesions;therefore, these lesions frequently cause acute life-threatening hemorrhage. Mechanical hemostasis using endoclips is recommended to treat DLs, considering the high re-bleeding rate after primary APC cauterization. Meanwhile, most small bowel AVMs are large and susceptible to re-bleeding therefore, they usually require surgical resection. To achieve optimal diagnostic and therapeutic approaches for each type of small bowel lesion, the differences in their epidemiology, pathology and clinical presentation must be understood.

中日胃肠毛细血管扩张症对比分析

目的加深临床上对毛细血管扩张症的认识。方法收集中日2个内镜中心毛细血管扩张症患者,研究对比发病率、发病部位、检查目的、伴随内镜表现和治疗方法等。结果日本发病率高于中国,左半结肠多发,氩离子凝固术(APC)及钛夹治疗有效。结论内镜诊治是毛细血管扩张症的首选方法。高龄患者消化道出血诊断困难者可行小肠镜检查。

Bleeding with the artificial heart: Gastrointestinal hemorrhage in CF-LVAD patients

Continuous-flow left ventricular assist devices(CF-LVADs)have significantly improved outcomes for patients with end-stage heart failure when used as a bridge to cardiac transplantation or,more recently,as destination therapy.However,its implantations carries a risk of complications including infection,device malfunction,arrhythmias,right ventricular failure,thromboembolic disease,postoperative and nonsurgical bleeding.A significant number of left ventricular assist devices(LVAD)recipients may experience recurrent gastrointestinal hemorrhage,mainly due to combination of antiplatelet and vitamin K antagonist therapy,activation of fibrinolytic pathway,acquired von Willebrand factor deficiency,and tendency to develop small intestinal angiodysplasias due to increased rotary speed of the pump.Gastrointestinal bleeding in LVAD patients remains a source of increased morbidity including the need for blood transfusions,extended hospital stays,multiple readmissions,and overall mortality.Management of gastrointestinal bleeding in LVAD patients involves multidisciplinary approach in stabilizing the patients,addressing risk factors and performing structured endoluminal evaluation with focus on upper gastrointestinal tract including jejunum to find and eradicate culprit lesion.Medical and procedural intervention is largely successful and universal bleeding cessation occurs in transplanted patients.

First report of splenic rupture following deep enteroscopy

Splenic rupture is a rare complication of diagnostic and therapeutic gastrointestinal endoscopy procedures.Herein,we report for the first time a case of splenic rupture following therapeutic retrograde double-balloon enteroscopy,which occurred in an 85-year-old man who was treated for recurrent mid-intestinal bleeding that resulted from ileal angioectasia.This patient promptly underwent an operation and eventually recovered.

Accuracy of community based video capsule endoscopy in patients undergoing follow up double balloon enteroscopy

AIM: To determine the test characteristics of community based video capsule endoscopy (VCE) in patients undergoing sequential VCE and double balloon enteroscopy (DBE). METHODS: Eighty-nine patients (34 females, 55 males, mean age 66) who underwent both VCE and DBE from 2008-2010 were retrospectively reviewed. Lesions detected at VCE were categorized. Capsule directed DBE followed and included 44 antegrade, 11 retrograde and 34 combined antegrade and retrograde procedures. Lesions detected were compared utilizing the McNemar's test. RESULTS: Angioectasia detection with VCE was 25% and with DBE 35% (P < 0.03) with a calculated sensitivity and specificity of 58% and 93% respectively. Polyps were detected by VCE in 22% and in DBE 20%, (P = 0.6), with a sensitivity and specificity for VCE of 61% and 87%. Small bowel diverticula were only seen in 1% of VCE but in 12% of DBE patients (P < 0.002) with a calculated sensitivity and specificity of VCE of 9% and 100%. CONCLUSION: VCE would be moderately sensitiveand specific overall with considerable variation by lesion. Furthermore, VCE cannot be relied upon to diagnose small bowel diverticula.

软组织多形性玻璃样变血管扩张性肿瘤的临床病理学观察

目的探讨软组织多形性玻璃样变血管扩张性肿瘤（pleomorphic hyalinizing angiectatic tumor of soft parts,PHAT）的临床病理特点。方法回顾性分析6例PHAT的临床资料、组织学形态和免疫组化标记,并复习相关文献。结果6例均发生于成年人,男性和女性各占3例,平均年龄为44岁。肿瘤分别位于下肢（3例）、颈部（2例）和腹膜后（1例）。临床上多表现为无痛性肿块,术前病程为3个月-38年。大体上,肿瘤境界清楚,结节状,平均直径为4.3 cm。切面呈灰白、灰红或灰褐色,部分病例可见出血性囊腔。镜下,肿瘤内含有成簇分布的薄壁扩张血管,血管壁附有一层厚的玻璃样变物质（纤维素和胶原纤维）,可向血管周围间质内延伸,血管之间为片状分布的多形性瘤细胞,核大深染,核内可见假包涵体,但核分裂象罕见。部分区域内瘤细胞呈梭形,排列成条束状,类似神经鞘瘤。免疫组化标记显示,瘤细胞主要表达vimentin,部分病例还表达CD34和CD99,而S-100蛋白、α-SMA、bcl-2、EMA和CD68均为阴性。6例均经手术切除,随访8个月-13年,无1例复发。结论PHAT是一种具有低度恶性潜能的软组织肿瘤，熟悉其形态学特征有助于诊断和鉴别诊断。临床上对PHAT宜采取完整性切除，并注意随访。

Three-dimensional image reconstruction in capsule endoscopy

To date,limited research has been carried out in developing methods and materials that offer three-dimensional(3-D) representation of the digestive tract.In the field of capsule endoscopy(CE),hardware approaches have been developed that provide real time both 3-D information and texture using an infrared projector and a complementary metal oxide semiconductor camera.The major drawbacks of this system are its size,power consumption and packaging issues.A software approach to approximate a 3-D representation of digestive tract surface utilising current CE technology has been proposed.The algorithm utilizes the Shape from Shading technique and seem to provide promising results for polypoid structures and angioectasias.Further clinical evaluation is currently under way.