Background & Aims: A specialized system for a new method for enteroscopy, the double-balloon method, was developed. The aim of this study was to evaluate the usefulness of this endoscopic system for small-intestinal disorders. Methods: The double-balloon endoscopy system was used to perform 178 enteroscopies (89 by the anterograde approach and 89 by the retrograde approach) in 123 patients. The system was assessed on the basis of the rates of success in jejunal and ileal insertion and the entire examination of the small intestine, diagnostic yields, ability to perform treatment, and complications. Results: Insertion of the endoscope beyond the ligament of Treitz or ileocecal valve was possible in all 178 procedures. It was possible to observe approximately one half to two thirds of the entire small intestine by each approach, and observation of the entire small intestine was possible in 24 (86%) of 28 trials. The source of bleeding was identified in 50 (76%) of 66 patients with GI bleeding, scrutiny of strictures was possible in 23 patients, and a tumor was examined endoscopically in 17 patients. Two complications (1.1%) occurred. Endoscopic therapies in the small intestine including hemostasis (12 cases), polypectomy (1 case), endoscopic mucosal resection (1 case), balloon dilation (6 cases), and stent placement (2 cases) were performed successfully. Conclusions: Double-balloon endoscopy permits the exploration of the small intestine with a high success rate of total enteroscopy. The procedure is safe and useful, and it provides high diagnostic yields and therapeutic capabilities. Background & Aims: A specialized system for a new method for enteroscopy, the double-balloon method, was developed. The aim of this study was to evaluate the usefulness of this endoscopic system for small-intestinal disorders. Methods: The double-balloon endoscopy system was used to perform 178 enteroscopies (89 by the anterograde approach and 89 by the retrograde approach) in 123 patients. The system was assessed on the basis of the rates of success in jejunal and ileal insertion and the entire examination of the small intestine, diagnostic yields, ability to perform treatment, and complications. Results: Insertion of the endoscope beyond the ligament of Treitz or ileocecal valve was possible in all 178 procedures. It was possible to observe approximately one half to two thirds of the entire small intestine by each approach, and observation of the entire small intestine was possible in 24 (86%) of 28 trials. The source of bleeding was identified in 50 (76%) of 66 patients with GI bleeding, scrutiny of strictures was possible in 23 patients, and a tumor was examined endoscopically in 17 patients. Two complications (1.1%) occurred. Endoscopic therapies in the small intestine including hemostasis (12 cases), polypectomy (1 case), endoscopic mucosal resection (1 case), balloon dilation (6 cases), and stent placement (2 cases) were performed successfully. Conclusions: Double-balloon endoscopy permits the exploration of the small intestine with a high success rate of total enteroscopy. The procedure is safe and useful, and it provides high diagnostic yields and therapeutic capabilities. Insertion of the endoscope into the distal small intestine has been challenging. The currently available methods of enteroscopy, including push enteroscopy, sonde method, and ropeway method, are not ideal in terms of accessibility, low invasiveness, and intervention capabilities.1Rossini F.P. Pennazio M. Small-bowel endoscopy.Endoscopy. 2002; 34: 13-20Crossref PubMed Scopus (53) Google Scholar Recently, wireless capsule endoscopy was introduced and proven to be superior to other conventional diagnostic modalities, including push enteroscopy and small-bowel radiography, for the evaluation of small-intestinal diseases.2Appleyard M. Fireman Z. Glukhovsky A. Jacob H. Shreiver R. Kadirkamanathan S. Lavy A. Lewkowicz S. Scapa E. Shofti R. Swain P. Zaretsky A. A randomized trial comparing wireless capsule endoscopy with push enteroscopy for the detection of small-bowel lesions.Gastroenterology. 2000; 119: 1431-1438Abstract Full Text Full Text PDF PubMed Scopus (427) Google Scholar, 3Costamagna G. Shah S.K. Riccioni M.E. Foschia F. Mutignani M. Perri V. Vecchioli A. Brizi M.G. Picciocchi A. Marano P. A prospective trial comparing small bowel radiographs and video capsule endoscopy for suspected small bowel disease.Gastroenterology. 2002; 123: 999-1005Abstract Full Text Full Text PDF PubMed Scopus (780) Google Scholar The currently available Given M2A capsule (Given Imaging Ltd., Yoqneam, Israel), however, has only a diagnostic function, with no ability to sample tissue or perform therapy. There are also considerable difficulties in the interpretation of nonspecific findings.3Costamagna G. Shah S.K. Riccioni M.E. Foschia F. Mutignani M. Perri V. Vecchioli A. Brizi M.G. Picciocchi A. Marano P. A prospective trial comparing small bowel radiographs and video capsule endoscopy for suspected small bowel disease.Gastroenterology. 2002; 123: 999-1005Abstract Full Text Full Text PDF PubMed Scopus (780) Google Scholar We previously reported a new insertion method for enteroscopy, the double-balloon method, which enables endoscopic scrutiny of the entire small intestine with intervention capabilities.4Yamamoto H. Sekine Y. Sato Y. Higashizawa T. Miyata T. Iino S. Ido K. Sugano K. Total enteroscopy with a nonsurgical steerable double-balloon method.Gastrointest Endosc. 2001; 53: 216-220Abstract Full Text Full Text PDF PubMed Scopus (1139) Google Scholar, 5Yamamoto H. Yano T. Kita H. Sunada K. Ido K. Sugano K. New system of double-balloon enteroscopy for diagnosis and treatment of small intestinal disorders.Gastroenterology. 2003; 125: 1556-1557Abstract Full Text Full Text PDF PubMed Scopus (201) Google Scholar, 6Yamamoto H. Sugano K. A new method of enteroscopy—the double-balloon method.Can J Gastroenterol. 2003; 17: 273-274PubMed Google Scholar, 7May A. Nachbar L. Wardak A. Yamamoto H. Ell C. Double-balloon enteroscopy preliminary experience in patients with obscure gastrointestinal bleeding or chronic abdominal pain.Endoscopy. 2003; 35: 985-991Crossref PubMed Scopus (249) Google Scholar This retrospective study was designed to address the clinical outcomes of this new endoscopy system for the diagnosis and treatment of small-intestinal diseases. Between September 2000 and March 2004, 178 enteroscopies, including 89 anterograde and 89 retrograde procedures, were performed on 123 patients in Jichi Medical School Hospital, Japan, using the Fujinon double-balloon endoscopy system (Fuji Photo Optical Co., Ltd., Saitama, Japan). In some patients, more than 1 enteroscopy was performed for endoscopic treatment of small-intestinal lesions or endoscopic assessment after the treatment. Double-balloon endoscopy was approved by the ethics committee of the school and written informed consent was obtained from all patients. The median age of the 123 patients (70 men, 53 women) was 60 years (range, 8–88 y). Indications for the enteroscopic examinations in these patients are listed in Table 1.Table 1Demographic Data of Patients Undergoing Double-Balloon EnteroscopyIndicationsObscure gastrointestinal bleedingObstructive symptomsSuspicion of intestinal tumorOther indicationsTotalNumber of patients66221132123Sex (men/women)40/2613/96/517/1570/53Median age (range)61 (13–88)54 (23–84)65 (46–84)60 (8–80)60 (8–88)NOTE. There is some overlap in a small number of patients in terms of 3 major indications; 2 patients had both obscure gastrointestinal bleeding and suspicion of intestinal tumor; 1 patient had both obscure gastrointestinal bleeding and obstructive symptoms; 3 patients had both obstructive symptoms and suspicion of intestinal tumor; 1 patient had all 3 indications. Other indications included technically difficult colonoscopy in 14 patients; abdominal pain in 6 patients; suspicions of Crohn’s disease in 5 patients; jaundice after Roux-en-Y surgery in 4 patients; and postoperative survey of small-intestinal cancer, postendoscopic treatment of small-intestinal carcinoid, small-intestinal invasion of pancreatic cancer, eosinophilic enterocolitis, and diarrhea each in 1 patient. Open table in a new tab NOTE. There is some overlap in a small number of patients in terms of 3 major indications; 2 patients had both obscure gastrointestinal bleeding and suspicion of intestinal tumor; 1 patient had both obscure gastrointestinal bleeding and obstructive symptoms; 3 patients had both obstructive symptoms and suspicion of intestinal tumor; 1 patient had all 3 indications. Other indications included technically difficult colonoscopy in 14 patients; abdominal pain in 6 patients; suspicions of Crohn’s disease in 5 patients; jaundice after Roux-en-Y surgery in 4 patients; and postoperative survey of small-intestinal cancer, postendoscopic treatment of small-intestinal carcinoid, small-intestinal invasion of pancreatic cancer, eosinophilic enterocolitis, and diarrhea each in 1 patient. The Fujinon double-balloon endoscopy system is composed of a thin endoscope with an 8.5-mm diameter and a 200-cm working length, a 145-cm soft overtube with an outer diameter of 12.2 mm, and a specifically designed pump (Figure 1). A soft latex balloon, attached at the tip of the endoscope, can be inflated and deflated using the pump through an air channel in the endoscope. The soft overtube also has a latex balloon at its tip that can be inflated and deflated. The pressure in both balloons is monitored accurately and regulated at 6 kPa. The specifications of this system are listed in Table 2.Table 2Specifications of Fujinon Double-Balloon SystemEndoscope: EN-450P5/20 Outer diameter8.5 mm Total length2300 mm Working length2000 mm Accessory channel2.2 mmOvertube: TS-12140 Outer diameter12.2 mm Inner diameter10 mm Total length1450 mm Working length1400 mmPump controller: PB-10 Pressure setting range3.6–7.6 kPa Maximum flow rate170 mL/10 s Open table in a new tab Accessory devices such as biopsy forceps, polypectomy snare, injection needle, hot biopsy forceps, coagulation forceps, and grasping forceps are available for this endoscope. Enteroscopy was performed with the patient under conscious sedation. Insertion procedures are described elsewhere.6Yamamoto H. Sugano K. A new method of enteroscopy—the double-balloon method.Can J Gastroenterol. 2003; 17: 273-274PubMed Google Scholar In summary, the overtube is back-loaded onto the endoscope with both balloons collapsed. The endoscope is advanced into the duodenum and the balloon on the endoscope tip is inflated there. The overtube then is inserted into the duodenum, and the overtube balloon also is inflated. After straightening the overtube and endoscope by gently withdrawing them, the endoscope balloon is deflated and the endoscope is inserted farther. After the tip of the endoscope has been inserted beyond the ligament of Treitz, the endoscope balloon is inflated and the overtube balloon is deflated, and the overtube then is advanced. Gentle, simultaneous withdrawal of the overtube and endoscope, with both balloons dilated, causes pleating of the intestine onto the overtube. This sequence is repeated to advance the endoscope increasingly farther into the intestine. The pleating (or accordian or gathering) effect of the intestine over and onto the overtube allows for the insertion of the endoscope into the small intestine well beyond the physical length of the endoscope itself (Figure 2). The procedure is performed under fluoroscopic guidance. A retrograde (anal) approach also is performed using the same principle. The latex balloons can be inflated sufficiently to grip the colonic wall while advancing through the colon because the balloons are very elastic and balloon dilatation is controlled by pressure instead of air volume, and therefore they can be used safely regardless of the intestinal diameter. After reaching the cecum, the endoscope is inserted into the ileum beyond the ileocecal valve, then the overtube also is inserted into the ileum. A tip to remember when advancing the endoscope into the distal small intestine using the double-balloon method is to form concentric circles with the endoscope. Advancing with a downward curve into the pelvis, forming the shape of the sigmoid, should be avoided. The insertion route was chosen according to the estimated location of the suspected lesions, that is, oral insertion was chosen when jejunal lesions were suspected and anal insertion was chosen when ileal lesions were suspected. A combination of both approaches was used in some patients, but examination of the entire small intestine was uncertain because there is no landmark in the small intestine. Therefore, a trial of total enteroscopy with a specific technique using India ink was executed in 28 consecutive patients for whom examination of the entire small intestine was desired. The indications of the examinations for these 28 patients included obscure gastrointestinal bleeding in 21 patients, obstructive symptom in 6 patients, and suspicion of an intestinal tumor in 1 patient. In this trial, the farthest point reached in the intestine was marked with India ink unless observation of the entire small intestine was accomplished by the initial procedure. When the mark was reached during a subsequent enteroscopy examination from the opposite direction, endoscopic observation of the entire small intestine was confirmed. The rates of successful insertion of the double-balloon endoscope into the small intestine by the anterograde approach and the retrograde approach were assessed separately. Insertion beyond the ligament of Treitz and endoscopic observation of the jejunum was achieved by the double-balloon method in all 89 anterograde insertion procedures, and the maximum depth of insertion was beyond the ileocecal valve into the ascending colon in 2 cases. The average depth of insertion estimated from the number of pleating procedures and the fluoroscopic images of the small intestine and endoscope was approximately one half to two thirds of the entire length of the small intestine. Indeed, it was difficult to determine the depth of insertion precisely because there are no clear anatomic landmarks in the small intestine and the length of the intestine can vary considerably as a result of the shortening and stretching. Insertion of the endoscope beyond the ileocecal valve was possible in all 89 retrograde approaches, and the farthest point reached was the ligament of Treitz in 1 case. The average depth of insertion by the retrograde approach estimated in a similar manner also was approximately one half to two thirds of the length of the entire small intestine. The use of fluoroscopy is not necessary in most of the situations during the insertion and observation with double-balloon enteroscopy because the overtube used in this method is soft and can be inserted along a curved endoscope. Fluoroscopy is necessary whenever an endoscope does not progress during insertion and the shape of the endoscope should be checked. While we were examining the small intestine by using the double-balloon enteroscopy, we found that the combination of both approaches causes less discomfort to the patients to explore the whole small intestine. Thus, we conducted a trial for the examination of whole small intestine by using India ink as a marker in the 28 consecutive patients as discussed in the next section. Despite the necessity of endoscopic examination of the entire small intestine, technical difficulties have been an obstacle up to this point. In our study, endoscopic observation of the entire small intestine was successful in 24 (86%) of the 28 patients in the trial of total enteroscopy, by anterograde approach alone in 2 patients and by a combination of both approaches in 22 patients (Table 3). The failure to explore the entire small intestine was ascertained when enteroscopy at the second approach did not reach the marking with India ink that was set at the first approach. The median insertion time required for the entire small intestine, calculated by adding the insertion time of both approaches for the combination cases, was 123 minutes (range, 77–180 min). The median insertion time was 73 minutes (range, 30–123 min) for the initial approach and 47 minutes (range, 27–100 min) for the opposite approach. It is important to note that 7 of the 24 patients in whom total enteroscopy was successful had a history of laparotomy.Table 3Clinical Data of Patients Who Have Undergone Total EnteroscopyInsertion routeNumber of patientsMedian insertion time (range, min)Previous laparotomyOral route only2114 (100–128)0Anal route only00Combination22123 (77–180)7 Initial approach (2 oral, 20 anal)73 (30–123) Opposite approach47 (27–100)Total24123 (77–180)7NOTE. Total enteroscopy was successful in 24 (86%) of 28 trials. The reasons for the failure in the 4 trials were: intestinal adhesion (3 trials) and balloon trouble (1 trial). Open table in a new tab NOTE. Total enteroscopy was successful in 24 (86%) of 28 trials. The reasons for the failure in the 4 trials were: intestinal adhesion (3 trials) and balloon trouble (1 trial). Diagnostic yields of the procedures for each disorder were analyzed. The bleeding source was identified in 50 of 66 patients with gastrointestinal bleeding. Major findings included small-intestinal ulcers and/or erosions in 22 patients, small-intestinal polyps and/or tumors in 10 patients, and small-intestinal angiodysplasia in 7 patients (Table 4). Strictures were found in 17 of 22 patients who presented with obstructive symptoms as the major indication, and 6 additional patients found to have strictures presented with other indications. Endoscopic scrutiny of the strictures by direct observation and tissue sampling was possible in all 23 patients (Table 5). The presence of a stricture was excluded in the other 5 patients with symptoms of bowel obstruction by total enteroscopy (1 case) or a combination of enteroscopy and selective radiographic examination during enteroscopy (4 cases). Small-intestinal tumors were found in 8 of 11 patients in whom a small-intestinal tumor was suspected based on the results of other examinations, and in 9 other patients who presented with other indications. In total, direct observation of the tumor was successful in all 17 patients with small-intestinal tumors (Table 6). In the remaining 3 patients who were suspected of having a small-intestinal tumor, the presence of the small-intestinal tumor was excluded by the double-balloon enteroscopy; 2 patients in whom tumor was found by abdominal computed tomography were determined to have an extraintestinal tumor; and 1 patient with multiple lymphomatoid ulcers in the ileum was determined to have benign ulcers by histopathologic examination. There was no patient in whom previous capsule endoscopy led to a suspicion of small intestinal tumor, although capsule endoscopy was performed in only 4 patients in total because there has been a limited usage of capsule endoscopy thus far in Japan.Table 4Endoscopic Diagnosis of Patients With Obscure Gastrointestinal BleedingEndoscopic diagnosisNumber of patientsNumber of patients (in detail)Ulcers and/or erosions22 NSAIDs7 Blind loop3 Crohn’s disease2 Meckel’s diverticulum2 Behçet disease2 Other small-intestinal ulcers6Small intestinal polyps and/or tumors10Small intestinal angiodysplasia7Other small-intestinal lesions4Colonic lesions4Esophageal or gastric lesions2Biliary bleeding1Total50NOTE. The bleeding source was identified in 50 (76%) of the 66 obscure gastrointestinal bleeding patients.NSAIDs, nonsteroidal anti-inflammatory drugs. Open table in a new tab Table 5Endoscopic Diagnosis of Patients With Small-Intestinal StricturesEndoscopic diagnosisNumber of patientsNumber of patients (in detail)Benign inflammatory stricture11 Crohn’s disease4 NSAIDs1 Posttraumatic stricture1 Anticoagulant ileus1 Other inflammatory stricture4Small-intestinal tumor6Extrinsic cause4 Adhesion3 Pancreatitis1Postoperative mechanical obstruction without stricture2Total23NSAIDs, nonsteroidal anti-inflammatory drugs. Open table in a new tab Table 6Endoscopic Diagnosis in Patients With Small-Intestinal TumorsEndoscopic diagnosisNumber of patientsSmall-intestinal cancer6GIST4Malignant lymphoma2Inflammatory fibroid polyp1Invasion of pancreatic cancer1Other small-intestinal polyps3Total17GIST, gastrointestinal stromal tumors. Open table in a new tab NOTE. The bleeding source was identified in 50 (76%) of the 66 obscure gastrointestinal bleeding patients. NSAIDs, nonsteroidal anti-inflammatory drugs. NSAIDs, nonsteroidal anti-inflammatory drugs. GIST, gastrointestinal stromal tumors. Endoscopic therapies in the small intestine such as hemostasis with electrocoagulation (12 cases), polypectomy (1 case), endoscopic mucosal resection (1 case), balloon dilation (6 cases), and stent placement (2 cases) were performed successfully using this system. An example is shown in Figure 3. Balloon dilation and stent placement were able to be performed by removing the endoscope, leaving a guidewire and the overtube close to the lesions.8Sunada K. Yamamoto H. Kita H. Yano T. Miyata T. Sekine Y. Kuno A. Onishi N. Iwamoto M. Sasaki A. Ido K. Sugano K. Case report successful treatment with balloon dilatation using a double-balloon enteroscope for a stricture in the small bowel of a patient with Crohn’s disease.Dig Endosc. 2004; 16: 237-240Crossref Scopus (24) Google Scholar By removing the endoscope, the diameter of accessory devices is no longer limited by the size of the endoscope channel. Moreover, the required length of the devices is also shorter because they are used through a 145-cm overtube instead of a 230-cm endoscope. CRE Wireguided Balloon Dilators (Boston Scientific Corp., Natick, MA) and Ultraflex Stent System (Boston Scientific Corp.) were used in this study. Two complications occurred among the 178 procedures, multiple perforations occurred in one patient with intestinal lymphoma that was thought to be caused by chemotherapy for the lymphoma and the other was in a patient discovered to have Crohn’s disease who had postoperative fever and abdominal pain. The need for endoscopic examination of the small intestine has been well established, and the advent of capsule endoscopy is undoubtedly a significant breakthrough for visual diagnosis of the small intestine because it enables easy access to the entire small intestine.9Iddan G. Meron G. Glukhovsky A. Swain P. Wireless capsule endoscopy.Nature. 2000; 405: 417Crossref PubMed Scopus (2405) Google Scholar, 10Faigel D.O. Fennerty M.B. “Cutting the cord” for capsule endoscopy.Gastroenterology. 2002; 123: 1385-1388Abstract Full Text Full Text PDF PubMed Scopus (45) Google Scholar In addition, we have established a new method of enteroscopy, the double-balloon method, that also allows direct access to the entire small intestine; the clinical value of this new method was evaluated in this study. The success rate of jejunal insertion by double-balloon endoscopy via the anterograde approach was 100% in this study. Endoscopic insertion into the jejunum by the conventional push method sometimes is hampered by a sharp bend in the intestine at the angle of Treitz,11Taylor A.C. Chen R.Y. Desmond P.V. Use of an overtube for enteroscopy—does it increase depth of insertion? A prospective study of enteroscopy with and without an overtube.Endoscopy. 2001; 33: 227-230Crossref PubMed Scopus (73) Google Scholar whereas gripping the duodenum with the overtube balloon while inserting the endoscope by the anterograde approach with the new system prevented bending of the intestine at the angle of Treitz. Because of this, we usually did not even recognize the angle of Treitz during insertion. Ileal examination by the retrograde approach also was successful in 100% of the 89 consecutive cases. Insertion of the endoscope beyond the ileocecal valve was accomplished easily by decreasing the angle between the ascending colon and the terminal ileum by gently pulling back the overtube, while fixating the ascending colon with its balloon. Endoscopic observation of the entire small intestine was successful in 86% of the 28 consecutive trials. Total enteroscopy was achieved by anterograde insertion alone in 2 patients, and by using a combination of both approaches in 22 patients. Retrograde insertion usually accompanies less discomfort than anterograde insertion. Therefore, when observation of the entire small intestine is intended, proceeding as far as possible with the retrograde approach is thought to be prudent to decrease the anterograde insertion time. Indeed, more than 90% of our total enteroscopy using both approaches was initiated from the retrograde approach. Reasons for failing to accomplish total enteroscopy included marked intestinal adhesion caused by previous laparotomy in 3 patients, and an overtube balloon rupture during the procedure in 1 patient in whom reinsertion of the enteroscope with a new balloon was not performed because a diagnosis of jejunal cancer already had been made. With the exception of the single balloon failure, total enteroscopy was successful in all 17 patients (100%) without a history of laparotomy. Moreover, total enteroscopy was successful despite a history of laparotomy in 7 (70%) of 10 patients. Intestinal adhesion interferes with insertion of double-balloon endoscopy because it hampers effective shortening of the intestine and causes sharp intestinal bending. The overall success rate of 86% is comparable with that of imaging the entire small intestine using a currently available M2A capsule, which was reported to be 79% in a recent study.12Pennazio M. Santucci R. Rondonotti E. Abbiati C. Beccari G. Rossini F.P. De Franchis R. Outcome of patients with obscure gastrointestinal bleeding after capsule endoscopy report of 100 consecutive cases.Gastroenterology. 2004; 126: 643-653Abstract Full Text Full Text PDF PubMed Scopus (853) Google Scholar Taken together, the double-balloon method is a highly reliable method of enteroscopy. The median insertion time required for total enteroscopy was 123 minutes, which is not an extraordinarily long time considering the length of the small intestine. Because total enteroscopy was achieved in most cases by combining the 2 approaches, the average insertion time for 1 procedure was approximately 60 minutes. In actual practice, the insertion time may be shorter because a survey of the entire small intestine is not always necessary. All procedures were tolerable by the patients under conscious sedation. Diagnostic yields of double-balloon enteroscopy in identifying the source of bleeding were satisfactory with positive results in 76% of obscure cases of gastrointestinal bleeding. This is comparable with previous reports of capsule endoscopy (30%–80%), although we did not conduct a direct comparison between capsule endoscopy and double-balloon endoscopy.12Pennazio M. Santucci R. Rondonotti E. Abbiati C. Beccari G. Rossini F.P. De Franchis R. Outcome of patients with obscure gastrointestinal bleeding after capsule endoscopy report of 100 consecutive cases.Gastroenterology. 2004; 126: 643-653Abstract Full Text Full Text PDF PubMed Scopus (853) Google Scholar, 13Saurin J.C. Delvaux M. Gaudin J.L. Fassler I. Villarejo J. Vahedi K. Bitoun A. Canard J.M. Souquet J.C. Ponchon T. Florent C. Gay G. Diagnostic value of endoscopic capsule in patients with obscure digestive bleeding blinded comparison with video push-enteroscopy.Endoscopy. 2003; 35: 576-584Crossref PubMed Scopus (68) Google Scholar However, our results are quite understandable because of the high diagnostic yield of push enteroscopy, which was at least comparable with capsule endoscopy as long as the comparison was limited to within the reach of push enteroscopy, and the high rate of successful observation of the entire small intestine using double-balloon endoscopy.2Appleyard M. Fireman Z. Glukhovsky A. Jacob H. Shreiver R. Kadirkamanathan S. Lavy A. Lewkowicz S. Scapa E. Shofti R. Swain P. Zaretsky A. A randomized trial comparing wireless capsule endoscopy with push enteroscopy for the detection of small-bowel lesions.Gastroenterology. 2000; 119: 1431-1438Abstract Full Text Full Text PDF PubMed Scopus (427) Google Scholar In our study, angiodysplasia represented 11% (7 of 66) of obscure gastrointestinal bleeding. This number is lower than the previously reported number of around 30%.12Pennazio M. Santucci R. Rondonotti E. Abbiati C. Beccari G. Rossini F.P. De Franchis R. Outcome of patients with obscure gastrointestinal bleeding after capsule endoscopy report of 100 consecutive cases.Gastroenterology. 2004; 126: 643-653Abstract Full Text Full Text PDF PubMed Scopus (853) Google Scholar, 13Saurin J.C. Delvaux M. Gaudin J.L. Fassler I. Villarejo J. Vahedi K. Bitoun A. Canard J.M. Souquet J.C. Ponchon T. Florent C. Gay G. Diagnostic value of endoscopic capsule in patients with obscure digestive bleeding blinded comparison with video push-enteroscopy.Endoscopy. 2003; 35: 576-584Crossref PubMed Scopus (68) Google Scholar, 14Ell C. Remke S. May A. Helou L. Henrich R. Mayer G. The first prospective controlled trial comparing wireless capsule endoscopy with push enteroscopy in chronic gastrointestinal bleeding.Endoscopy. 2002; 34: 685-689Crossref PubMed Scopus (662) Google Scholar One possible explanation for this discrepancy is that we counted only dominant findings as responsible lesions for gastrointestinal bleeding. Angiodysplasia was found in 4 more patients but they were not included because they had other lesions responsible for bleeding such as ulcers or tumors. Another possibility is the difference of ethnicity of the patients. This hypothesis will be elucidated further as our experience with double-balloon endoscopy and capsule endoscopy accumulates. It also is plausible that this type of enteroscopy may form small traumatic lesions during insertion, which could be confounded with ulceration or erosion. Thus, our data also may overestimate the frequency of ulceration or erosion, although we believe that ulcers or erosions can be distinguished from small traumatic lesions because they usually accompany changes of villi around them. The capability of real-time observation as well as histopathologic assessment with a targeted biopsy examination is an advantage of double-balloon endoscopy as compared with capsule endoscopy. Another advantage of double-balloon endoscopy is the ability to examine small-intestinal strictures because capsule endoscopy is contraindicated when strictures are suspected in the bowel.10Faigel D.O. Fennerty M.B. “Cutting the cord” for capsule endoscopy.Gastroenterology. 2002; 123: 1385-1388Abstract Full Text Full Text PDF PubMed Scopus (45) Google Scholar In the current study, detailed observation of strictures was successful in all 23 patients with small-intestinal strictures. Endoscopic confirmation also was successful in all 17 patients with small-intestinal tumors. Although the diagnostic yield of double-balloon endoscopy is difficult to assess because of the lack of a gold standard, our results suggest that this new technique is a highly reliable diagnostic tool for small-intestinal disorders. The ability to perform endoscopic treatment is another advantage of double-balloon endoscopy. In the current study, endoscopic therapies such as hemostasis, polypectomy, endoscopic mucosal resection, balloon dilatation, and stent placement were performed successfully using the double-balloon system, even for lesions located deep in the small intestine, because the route to the lesion was shortened and access to the lesion was maintained with the overtube, whose balloon was gripping a portion of the intestine close to the lesion. Moreover, precise control of the endoscope tip was possible at any point in the intestine because the movement of the endoscope was controlled from the gripped point by the overtube balloon. Thus, this new method of enteroscopy is a very promising tool for endoscopic treatment once the lesion is reached. As mentioned previously, there were 2 cases of complications among 178 double-balloon enteroscopic procedures. Surgical repair was required in 1 patient with multiple perforations of the small intestine caused by chemotherapy of the small-intestinal lymphoma. Careful consideration is necessary for endoscopic evaluation of small-intestinal tumors after chemotherapy because of a high incidence of perforation.15Torosian M.H. Turnbull A.D. Emergency laparotomy for spontaneous intestinal and colonic perforations in cancer patients receiving corticosteroids and chemotherapy.J Clin Oncol. 1988; 6: 291-296PubMed Google Scholar In the other patient, exacerbation of Crohn’s disease after the enteroscopic procedure may have been caused by the endoscopic stimuli to the fresh ulcers, resulting in a microperforation at the ulcer bed which penetrated to the mesentery. If fragile lesions, such as fresh ulcers or tumors with deep ulcerations, are encountered, it is wise to avoid additional insertion of the endoscope beyond them. Both capsule endoscopy and double-balloon endoscopy can explore the entire small intestine with a high success rate. Capsule endoscopy is suitable for the initial work-up of nonobstructive small-intestinal disorders because it is a discomfort-free examination that does not require confinement of the patient to medical facilities. On the other hand, double-balloon endoscopy is more labor intensive, but has distinct advantages that can complement the limitations of capsule endoscopy. Although capsule endoscopy and double-balloon endoscopy should be considered as complementary procedures in this respect, a comparison study is necessary to determine the role of these procedures in the evaluation of small-intestinal disorders.