Study Of Clinical Value Of Capsule Endoscopy In Small-intestinal Disease

Introduction:The small bowel is the most difficult part of the bowel to be examined owing to the distance from the mouth to anus. The length of small intestine is about 5~7 meters which occupies 2/3 of total digestive tract The small intestine has lots of complex ansa intestinalis tied by mesenterium. Lesions located in the small bowel, can be only partially detected by conventional endoscopy. Conventional endoscopic techniques for examining the small bowel are limited by its length and its multiple, complex, looped configurations. For a wide variety of specific lesions, the diagnostic value of other tests for imaging the small bowel is limited. Radiographic techniques for evaluation of the small bowel are relatively insensitive for flat, small, infiltrative, or inflammatory bleeding lesions. Other imaging techniques such as angiography and radioisotope bleeding scan are insensitive in the absence of brisk bleeding. Push enteroscopy is presently considered an effective diagnostic procedure, however, it is technically complex, poorly tolerated, and carries a moderate risk of complications. In addition, it is time consuming and only allows the exploration of the jejunum. As a consequence, establishing the diagnosis in patients with suspected small intestinal disease can be difficult. The Given M2A video capsule system (Given Imaging Ltd., Yoqneam, Israel)-capsule endoscopy-is a new method of direct visualization of the small bowel that providesnoninvasive examination of areas of the gut that are not accessible through conventional endoscopy. The main advantage of CE is the ability to provide a more complete endoscopic evaluation of the small bowel than that of being previously been available. Other advantages include relatively low risk for the patient, absence of radiation, and minimal discomfort Upon on this, large samples of suspected small intestinal diseases and asymptomatic people were performed by capsule endoscopy and Mutiple-detector computer tomography in our study. The results of ratio of succeeding in CE, ratio of positive findings, diagnostic yield and pathological lesions were analyzed. Also we evaluated the diagnostic value of capsule endoscopy in small intestinal disease and summarized the causes of failure in capsule endoscopy and missing in diagnosis. Finally we evaluated the practiablity of capsule endoscopy considered as routinal screening method in asymptomatic cases.Patients and Methods:1. Diagnostic value of capsule endoscopy in small intestinal diseaseWe studied 346 patients (226 men, 120 women;mean age 48.3 years, range 13~90 years) who underwent capsule endoscopy during June 2003 to January 2006 in The First Affiliated Hospital, College of Medicine, Zhejiang University. 296 people were suspected small-intestinal diseases (187 men, 109 women;mean age 48.8 years) , the other 50 people were asymptomatic cases (40 men, 10 women;mean age 45.1 years) . We divided suspected small-intestinal disease people into groups as obscure gastrointestinal bleeding (OGIB ) (63 men, 59 women;mean age 55.1 years), suspected Crohn's disease(suspected CD)(39 men, 11 women;mean age 36.0 years), chronic abdominal pain (64 men, 29 women;mean age 47.9 years) and chronic diarrhea (21men, 10 women;mean age 47.8 years) . Obscure gastrointestinal bleeding was divided into acutemassive bleeding (17 men, 14 women;mean age 52.1 years) and recurrent melena (46 men, 45 women;mean age 56.1years) . Exclusion criteria were recent history of bowel obstruction and cannot tolerate operation, pacemaker implantation, and pregnancy. Evaluation criteria include ? Succeeding in CE means capsule reaching terminal ileum or detecting lesions before reaching terminal ileum ?Failure in CE means capsule not reaching terminal ileum and not detecting any lesion or stoping examination for all kinds of reasons (DPassing ileocecal valve means capsule has passed ileocecal valve during working time ?Positive findings mean lesions detected by CE ?Diagnostic yield means that lesions detected by CE could answered for origin of the disease.The Given video capsule system (Given Imaging Ltd.) consists of 3 elements: a disposable, swallowable capsule (M2A) that acquires video images during natural propulsion through the digestive system;An antenna array taped to the patient's abdomen and connected to a recorder that received and recorded the transmitted data;a workstation for processing, viewing and reporting of data acquired through the GI tract. The day before capsule endoscopy, patients were kept on a fluid diet for 24 hours and observed a fasting period for 12 hours. An oral purge was given in the afternoon and simethicone (15 ml) was given at 30 minutes before examination. Written informed consent was obtained from all patients before the procedure. Patients swallowed the capsule and remained under continuous medical supervision throughout the recording. They were allowed to consume a light meal at 4 hours after ingestion of the capsule. The recorder was disconnected at about 8 hours after the beginning of the study. The patients were requested to verify the natural excretion of the capsule in the stool and advised to avoid exposure to magnetic fields. Statistical analysis was performed using the x2 test (using Fisher's exact probabilities in 2 X 2 table when T<\);Significance was accepted at a value of P<0.05.2. Diagnostic value of capsule endoscopy combining with Mutiple-detector computer tomography in obscure gastrointestinal bleedingWe studied 60 patients (35 men, 25 women;mean age 53.8 years, range 17-84 years) with obscure gastrointestinal bleeding who underwent both capsule endoscopy and Mutiple-detector computer tomography during November 2003 to December 2005 in The First Affiliated Hospital, College of Medicine, Zhejiang University. All patients had hemafecia or recurrent melena or iron deficiency anemia, and gastroscopy and colonoscopy did not disclose a source of bleeding. Finally, 28 patients were performed operation after examinations.In our study, we used Given video capsule system (Given Imaging Ltd.) . The day before capsule endoscopy, patients were kept on a fluid diet for 24 hours and observed a fasting period for 12 hours. An oral purge was given in the afternoon and simethicone was given at 30 minutes before examination. Written informed consent was obtained from all patients before the procedure. Patients swallowed the capsule in the morning and remained under continuous medical supervision throughout the recording. They were allowed to consume a light meal at 4 hours after ingestion of the capsule. The recorder was disconnected at about 8 hours after the beginning of the study. The patients were requested to verify the natural excretion of the capsule in the stool and advised to avoid exposure to magnetic fields.Mutiple-detector computer tomographies (Qullion 16 lines, Toshiba and MX8000 4 lines, PhiHp Medical System) were used. Thick of collimating layer and rebuilding layer is l-3mm and 5 mm respectively. The pitch is 1.2. Patients were observed a fasting period for 8 hours and took 0.9% normal saline (ID in 20 minutes before scanning. The scope of scan is from diaphragmatic dome to articulation of pubis. After plain scanning, patients were injected constrast agent (100 ml)with 3ml/sec velocity into antecubital vein. Scannings of arterial phase and parenchymal phase were performed at 30 seconds and 60 seconds after injection, respectively. Statistical analysis was performed using the x2 test of paired comparison of enoumeration data;Significance was accepted at a value of P<0.05.Results:1. Diagnostic value of capsule endoscopy in small intestinal diseaseAll patients easily swallowed the capsule;none reported any symptoms during the procedure. Bowel preparation with simethicone yielded significantly good visibility of the bowel mucosa to observersC except for 18 patients). Natural excretion of the capsule occurred in all asymptomatic cases, hi the group of suspected small-intestinal disease, delayed excretion of the capsule occurred in 16 patients, which the main causes were intestinal tumors and Crohn's diseases.6 of them were performed surgery (3 were intestinal tumors, 3 were Crohn's diseases) , the remain whose capsules were excreted at last through drugs treatment. The longest capsule retention lasted for 3 months. 341 of 346 patients succeeded in capsule endoscopy. The results detected by CE of each groups were shown in Table l.The ratio of positive findings in suspected small-intestinal disease was higher man that of group of symptomless, P<0.05.Lesions detected by CE in CD were ulcer ^ pebble-like change or inflammatory polyp> mucous hyperemia and erosion.The diagnostic yield of suspected CD and OGIB was higher than that of chronic abdominal pain and chronic diarrhea. The diagnostic yield of suspected CD was highest in all groups.Lesions detected by CE in obscure gastrointestinal bleeding are shown in Table 2.TablelResults of CETotalPart of patients succeeding in CEGroupsnRatio of succeedingRatio of passingRatio of positiveDiagnosticin CE{%)ileocecal valve(%)findings(%)yield(%)Suspected small-intsetinal29698.31%74.57%70.79%48.11%disease(291/296)(217/291)(206/291)(140/291)Obscure gastrointestinal12296.71%73.72%82.20%59.32%bleeding(118/122)(87/118)(97/118)(70/118)Acute massive bleeding3187.10%70.37%77.78%51.85%(27/31)(19/27)(21/27)(14/27)Recurrent melena91100%74.72%83.52%61.54%(91/91)(68/91)(76/91)(56/91)Suspected Crohn's disease5098%42.86%87.76%83.67%(49/50)(21/50)(43/49)(41/49)Chronic abdominal pain93100%87.1058.06%23.66%(93/93)(81/93)(54/93)(22/93)Chronic diarrhea31100%90.32%38.71%22.58%(31/31)(28/31)(12/31)(7/31)Asymptomatic people50100%94%32%—(50/50)(47/50)(16/50)Table2 Lesions in OGIB by CELesionsAcute massive bleeding (n) Recurrent melena (n)Vascular malformation6Small bowel tumour3Crohn's disease1Intestinal lymphangiectasia5Nonspecific enteritis0Ancylostostomiasis1Polyp1Lymph foilicie hyperplasia0Angioma2Meckel' s diverticulum1Isolated intestinal ulcer1Enterocyst1Superior mesenteric arterial thrombus1Roundworm1Total244012766433221000862. Diagnostic value of capsule endoscopy combining with Mutipte-detector computer tomography in obscure gastrointestinal bleedingAll patients underwent both CE and MDCT successfully. Natural excretion of the capsule occurred in 58 patients. 2 patients whose capsules stayed in lesions were performed by operation. Capsule endoscopy identified positive findings in 36 (60%) patients, whereas, MDCT identified positive findings in 23 (38.33%) patients, P<0.01. One patient was found 2 lesions by CE simultaneously. CE combining with MDCT identified positive findings in 39 ( 65% ) , which compared to CE, P>0.05;whereas, which compared to MDCT, P<0.01.28 of 60 patients underwent operations at last, which lesions all located in small intestine (16 in jejunum, 10 in ileum) . The results of CE, MDCT and surgery were shown in table 3.2 intestitialoma and 2 angiomas (diagnosed small intestinal bleeding by CE) were missed by CE, which were found by MDCT. 2 intestitialoma and 1 angioma were also missed by MDCT, which were found by CE.1aortoenteric fistula was missed by both CE and MDCT.Table 3 The results of CE, MDCT and surgeryTypes of lesionsDiagnosis (n)CEMDCTSurgeryInterstitiloma9911Crohn's disease52-Ancylostostomiasis40-Meckel' s diverticulum333Angioma345Angiodysplasia203Nonspecific enteritis30-Isolated intestinal ulcer201Superior meesenter artery embolus111Lipoma222Lymphoma111Polyp101Metastatic malignant melanoma11-Arotoenteric fistula001Total372329Conclusions:1. Capsule endoscopy was a noninvasive examination of direct visualization of the small bowel and had high diagnostic yield, which was strongly recommended as the first choice in investigating of small-intestinal disease.2. The first diagnostic value by CE was that in suspected Crohn's disease, the second in obscure gastrointestinal bleeding, the third in chronic abdominal pain and chronic diarrhea. If chronic abdominal pain and chronic diarrhea had other complication, diagnostic yield should rise.3. It was less different diagnostic yield between acute massive bleeding and recurrent melena.4. Diagnostic yield of CE was higher than that of MDCT in patients of obscure gastrointestinal bleeding, but P>0.05.5. MDCT showed estraintestinal lesions of intestinal tumors, we suggest mat the patients of obscure gastrointestinal bleeding be undergone by not only CE but also MDCT.