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Majerus SJA, Cabal D, Hacohen Y, Hanzlicek B, Smiley A, Wang Y, Liu W, Larauche M, Million M, Damaser MS, Bourbeau DJ. A Flexible Implant for Multi-Day Monitoring of Colon Segment Activity. IEEE TRANSACTIONS ON BIOMEDICAL CIRCUITS AND SYSTEMS 2023; 17:941-951. [PMID: 37363840 PMCID: PMC10732233 DOI: 10.1109/tbcas.2023.3289768] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/28/2023]
Abstract
Monitoring of colon activity is currently limited to tethered systems like anorectal manometry. These systems have significant drawbacks, but fundamentally limit the observation time of colon activity, reducing the likelihood of detecting specific clinical events. While significant technological advancement has been directed to mobile sensor capsules, this work describes the development and feasibility of a stationary sensor for describing the coordinated activity between neighboring segments of the colon. Unlike wireless capsules, this device remains in position and measures propagating pressure waves and impedances between colon segments to describe activity and motility. This low-power, flexible, wireless sensor-the colon monitor to capture activity (ColoMOCA) was validated in situ and in vivo over seven days of implantation. The ColoMOCA diameter was similar to common endoscopes to allow for minimally invasive diagnostic placement. The ColoMOCA included two pressure sensors, and three impedance-sensing electrodes arranged to describe the differential pressures and motility between adjacent colon segments. To prevent damage after placement in the colon, the ColoMOCA was fabricated with a flexible polyimide circuit board and a silicone rubber housing. The resulting device was highly flexible and suitable for surgical attachment to the colon wall. In vivo testing performed in eleven animals demonstrated suitability of both short term (less than 3 hours) and 7-day implantations. Data collected wirelessly from animal experiments demonstrated the ColoMOCA described colon activity similarly to wired catheters and allowed untethered, conscious monitoring of organ behavior.
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Horovistiz A, Oliveira M, Araújo H. Computer vision-based solutions to overcome the limitations of wireless capsule endoscopy. J Med Eng Technol 2023; 47:242-261. [PMID: 38231042 DOI: 10.1080/03091902.2024.2302025] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2022] [Accepted: 12/28/2023] [Indexed: 01/18/2024]
Abstract
Endoscopic investigation plays a critical role in the diagnosis of gastrointestinal (GI) diseases. Since 2001, Wireless Capsule Endoscopy (WCE) has been available for small bowel exploration and is in continuous development. Over the last decade, WCE has achieved impressive improvements in areas such as miniaturisation, image quality and battery life. As a result, WCE is currently a very useful alternative to wired enteroscopy in the investigation of various small bowel abnormalities and has the potential to become the leading screening technique for the entire gastrointestinal tract. However, commercial solutions still have several limitations, namely incomplete examination and limited diagnostic capacity. These deficiencies are related to technical issues, such as image quality, motion estimation and power consumption management. Computational methods, based on image processing and analysis, can help to overcome these challenges and reduce both the time required by reviewers and human interpretation errors. Research groups have proposed a series of methods including algorithms for locating the capsule or lesion, assessing intestinal motility and improving image quality.In this work, we provide a critical review of computational vision-based methods for WCE image analysis aimed at overcoming the technological challenges of capsules. This article also reviews several representative public datasets used to evaluate the performance of WCE techniques and methods. Finally, some promising solutions of computational methods based on the analysis of multiple-camera endoscopic images are presented.
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Affiliation(s)
- Ana Horovistiz
- Institute of Systems and Robotics, University of Coimbra, Coimbra, Portugal
| | - Marina Oliveira
- Institute of Systems and Robotics, University of Coimbra, Coimbra, Portugal
- Department of Electrical and Computer Engineering (DEEC), Faculty of Sciences and Technology, University of Coimbra, Coimbra, Portugal
| | - Helder Araújo
- Institute of Systems and Robotics, University of Coimbra, Coimbra, Portugal
- Department of Electrical and Computer Engineering (DEEC), Faculty of Sciences and Technology, University of Coimbra, Coimbra, Portugal
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Which model of small bowel capsule endoscopy has a better diagnostic yield? A systematic review and meta-analysis. Acta Gastroenterol Belg 2022; 85:509-517. [DOI: 10.51821/85.3.10322] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
Background and study aims: Small-bowel capsule endoscopy (SBCE) is a safe and efficient method for diagnosis of small-bowel diseases. Since its development, different models have appeared. The aim of this study was to analyze which of the different models of SBCE has the best diagnostic yield.
Patients and methods: Extensive medical literature research was reviewed, using MESH terms, searching studies comparing different SBCE types. We analyzed the diagnostic yield of all the comparisons and when there were 2 or more studies that compared the same model of SBCEs, a meta-analysis was performed.
Results: Ten eligible studies including 1065 SBCEs procedures were identified. The main indication was occult gastrointestinal bleeding in 9/10 studies. Two of them included anemia, chronic diarrhea and/or chronic abdominal pain. The indication in one article was celiac disease. In 9 studies, different types of SBCEs (MiroCam, Endocapsule, OMOM and CapsoCam) were compared with PillCam (SB, SB2 and SB3). Three studies compared MiroCam vs PillCam and CapsoCam vs PillCam, while two studies contrast Endocapsule vs PillCam. None of the SBCEs show superiority over PillCam [OR 0.78 (95%CI;0.60-1.01)]. One study compared SBCEs other than Pillcam (MiroCam vs Endocapsule). Nine studies did not find statistical differences between SBCEs, one showed better diagnostic yield of Mirocam compared with PillCam SB3 (p=0.02). The difference between these SBCE was not replayed in the metaanalysis [OR 0.77 (95%CI;0.49-1.21)].
Conclusions: Despite the appearance of new SBCE models, there are no differences in diagnostic yield; therefore, SBCE endoscopist’s performance should be based on experience and availability.
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Cox II GA, Jackson CS, Vega KJ. Artificial intelligence as a means to improve recognition of gastrointestinal angiodysplasia in video capsule endoscopy. Artif Intell Gastrointest Endosc 2021; 2:179-184. [DOI: 10.37126/aige.v2.i4.179] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/03/2021] [Revised: 07/07/2021] [Accepted: 08/13/2021] [Indexed: 02/06/2023] Open
Abstract
Gastrointestinal angiodysplasia (GIAD) is defined as the pathological process where blood vessels, typically venules and capillaries, become engorged, tortuous and thin walled – which then form arteriovenous connections within the mucosal and submucosal layers of the gastrointestinal tract. GIADs are a significant cause of gastrointestinal bleeding and are the main cause for suspected small bowel bleeding. To make the diagnosis, gastroenterologists rely on the use of video capsule endoscopy (VCE) to “target” GIAD. However, the use of VCE can be cumbersome secondary to reader fatigue, suboptimal preparation, and difficulty in distinguishing images. The human eye is imperfect. The same capsule study read by two different readers are noted to have miss rates like other forms of endoscopy. Artificial intelligence (AI) has been a means to bridge the gap between human imperfection and recognition of GIAD. The use of AI in VCE have shown that detection has improved, however the other burdens and limitations still need to be addressed. The use of AI for the diagnosis of GIAD shows promise and the changes needed to enhance the current practice of VCE are near.
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Affiliation(s)
- Gerald A Cox II
- Department of Medicine, Loma Linda University Medical Center, Loma Linda, CA 92354, United States
| | - Christian S Jackson
- Gastroenterology Section, VA Loma Linda Healthcare System, Loma Linda, CA 92357, United States
| | - Kenneth J Vega
- Division of Gastroenterology and Hepatology, Augusta University - Medical College of Georgia, Augusta, GA 30912, United States
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Blanco Velasco G, González-Virla B, Palos-Cuéllar R, Pérez-Cuadrado Robles E, Vargas-Ortega G, Solórzano-Pineda OM, Mendoza-Zubieta V, Hernández-Mondragón OV. Detection of polyps in the small bowel of patients with acromegaly via capsule endoscopy. REVISTA ESPANOLA DE ENFERMEDADES DIGESTIVAS 2021; 112:118-120. [PMID: 31960686 DOI: 10.17235/reed.2020.6377/2019] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
BACKGROUND the prevalence of small bowel (SB) polyps is unknown in acromegaly patients. OBJECTIVE to evaluate the prevalence of polyps/tumors in SB of acromegaly patients. MATERIAL this was a prospective and observational study that compared the prevalence of polyps/tumors using capsule endoscopy with a standard protocol in asymptomatic acromegaly patients and non-acromegaly patients, with abdominal pain, diarrhea or anemia. RESULTS one hundred and eighty-three cases were included (61 acromegaly and 122 non-acromegaly). Polyps were found in six (9.8%) and three (2.5%) patients, respectively (RR: 4 [95% CI, 1.03-15.45; p = 0.038]). There were no differences in the tumors (n = 4, 6.6% vs n = 7, 5.7%). CONCLUSIONS acromegaly may be associated with more polyps in SB.
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Affiliation(s)
| | - Baldomero González-Virla
- Endocrinología, Hospital de Especialidades, Centro Médico Nacional Siglo XXI, Instituto Mexicano del Seguro Social
| | - Raquel Palos-Cuéllar
- Endoscopia, Hospital de Especialidades, Centro Médico Nacional Siglo XXI, Instituto Mexicano del Seguro Social
| | | | - Guadalupe Vargas-Ortega
- Endocrinología, Hospital de Especialidades, Centro Médico Nacional Siglo XXI, Instituto Mexicano del Seguro Social
| | | | - Victoria Mendoza-Zubieta
- Endocrinología, Hospital de Especialidades, Centro Médico Nacional Siglo XXI, Instituto Mexicano del Seguro Social
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Blanco-Velasco G, Zamarripa-Mottú RA, Solórzano-Pineda OM, Mascarenhas-Saraiva M, Blancas-Valencia JM, Hernández-Mondragón OV. Comparison in the Diagnostic Yield between "Pillcam SB3" Capsule Endoscopy and "OMOM Smart Capsule 2" in Small Bowel Bleeding: A Randomized Head-to-Head Study. Dig Dis 2020; 39:211-216. [PMID: 33011721 DOI: 10.1159/000511958] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/27/2020] [Accepted: 10/02/2020] [Indexed: 02/02/2023]
Abstract
INTRODUCTION Capsule endoscopy (CE) is the first-line tool for diagnosis of small bowel bleeding. There are some studies that have compared different types of CE. OMOM CE is one of the newest in the market and has not been compared with other types of CE. The objective of this study was to compare the diagnostic yield of the Pillcam SB3 and OMOM CE in small bowel bleeding. MATERIALS AND METHODS This is a prospective, comparative, randomized, and blinded study. Patients with suspected small bowel bleeding were included. All the patients were given both types of CE in random order. Diagnostic yield and functionality between the 2 types of CE were analyzed. RESULTS We included 44 patients, 54.5% were female with a median age of 63.5 years. Battery time was significantly longer with SB3 (816.5 vs. 700.5 min, p < 0.001), and the download time was shorter with OMOM (33 vs. 132 min, p < 0.001). Both CEs presented 1 failure. The cause of the bleeding was identified in 39 SB3 (88.6%) and in 34 OMOM CE (77.3%) (p = 0.256). P2 lesions were observed in 32 SB3 (72.7%) and in 29 OMOM CE (65.9%) (p = 0.784). The agreement between both CEs for P2 lesions was moderate (κ = 0.628). CONCLUSIONS Pillcam SB3 and OMOM devices are safe procedures and have a similar diagnostic yield. Significant differences were observed in the battery life and download time with both CEs.
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Affiliation(s)
- Gerardo Blanco-Velasco
- Division of Endoscopy, Specialties Hospital, National Medical Center Century XXI, Mexico City, Mexico,
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Kharazmi AA, Aslani S, Kristiansen MF, Dahl EE, Berner-Hansen M. Indications and diagnostic yield of small-bowel capsule endoscopy in a real-world setting. BMC Gastroenterol 2020; 20:177. [PMID: 32513115 PMCID: PMC7282185 DOI: 10.1186/s12876-020-01326-8] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/02/2019] [Accepted: 06/01/2020] [Indexed: 02/07/2023] Open
Abstract
Background Indications and diagnostic yield of small-bowel video capsule endoscopy (SB-VCE) are communicated in recent clinical academic guidelines. However, guidelines are based mainly on relatively few, small, selection-biased studies at experienced centers, and thus we lack information on indications and diagnostic yield of SB-VCE in the real-world community setting. The aim of the study was to evaluate indications and diagnostic yield of SB-VCE in the real-world community setting. Methods Our local VCE clinical database was used to identify patients undergoing SB-VCE procedures over a 7-year period (2011–2018). Patients were broadly referred and underwent SB-VCE using PillCam™ SB 2 and SB 3 capsule systems. Procedures were reviewed by local endoscopists, who had undergone similar formal SB-VCE review training. Medical reports of the procedures were composed as such. We retrospectively reviewed all reports and gathered data regarding indications and findings. Diagnostic yield was considered positive if SB-VCE visualized any type of clinically significant pathological finding. Results 536 SB-VCE procedures in 516 patients were included in final assessment. Patient mean (± SD) age was 50 ± 20 years with approximately even female/male ratio (275:241). The overall proportion of positive findings was 42% (225/536). The two main indications were obscure gastrointestinal bleeding (occult/anemia or overt/active, OGIB) of 46% (246/536) and definite/suspected Crohn’s disease (CD) of 39% (210/536). Positive SB-VCE findings were obtained in 44% (108/246) of procedures with indication of OGIB and in 50% (104/210) of procedures with indication of CD. Conclusions The indications for SB-VCE are largely consistent with guidelines but with an apparently relatively low diagnostic yield in our real-world community setting.
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Affiliation(s)
- André Artan Kharazmi
- Digestive Disease Center, Bispebjerg Hospital, University of Copenhagen, Bispebjerg Bakke 23, DK-2400, Copenhagen NV, Denmark.
| | - Saeid Aslani
- Digestive Disease Center, Bispebjerg Hospital, University of Copenhagen, Bispebjerg Bakke 23, DK-2400, Copenhagen NV, Denmark
| | - Malene Fey Kristiansen
- Digestive Disease Center, Bispebjerg Hospital, University of Copenhagen, Bispebjerg Bakke 23, DK-2400, Copenhagen NV, Denmark
| | - Eva Efsen Dahl
- Digestive Disease Center, Bispebjerg Hospital, University of Copenhagen, Bispebjerg Bakke 23, DK-2400, Copenhagen NV, Denmark
| | - Mark Berner-Hansen
- Digestive Disease Center, Bispebjerg Hospital, University of Copenhagen, Bispebjerg Bakke 23, DK-2400, Copenhagen NV, Denmark
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Fluoroscopic-guided laparoscopic ileocolic resection with retrieval of retained (PillCam ®) wireless capsule endoscope. Tech Coloproctol 2019; 23:929-930. [PMID: 31440951 DOI: 10.1007/s10151-019-02062-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/14/2019] [Accepted: 08/07/2019] [Indexed: 10/26/2022]
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Tsuboi A, Oka S, Tanaka S, Iio S, Otani I, Kunihara S, Chayama K. The Clinical Usefulness of the PillCam Progress Indicator for Route Selection in Double Balloon Endoscopy. Intern Med 2019; 58:1375-1381. [PMID: 30626833 PMCID: PMC6548919 DOI: 10.2169/internalmedicine.2043-18] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
Objective The utility of capsule endoscopy (CE) findings in the route selection for double balloon endoscopy (DBE) has not been adequately discussed. The PillCam Progress Indicator in the RAPID 6.5 software program graphically demonstrates the progress of the capsule endoscope through the small-bowel. This study aimed to clarify the usefulness of the PillCam Progress Indicator in choosing the initial DBE route. Methods We retrospectively examined 50 consecutive patients with 50 target lesions detected on both CE and DBE at Hiroshima University Hospital from January 2011 to February 2018. In this study, we selected antegrade DBE on the basis of % Capsule Progress <50% as a clinical trial. The association between the PillCam Progress Indicator data and the DBE route to the target lesion was analyzed. Results The target lesion was reached via the initial DBE route in 96% (48/50) of cases. The cutoff values for selecting an antegrade route for DBE were 50% for % Capsule Progress and 42% for % SB Time. At the cutoff value, the sensitivity, specificity, and positive and negative predictive values for route selection were 100%, 91%, 93%, and 100% for % Capsule Progress and 96%, 91%, 93%, and 95% for % SB Time. Conclusion The PillCam Progress Indicator was useful for determining the appropriate initial DBE route.
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Affiliation(s)
- Akiyoshi Tsuboi
- Department of Gastroenterology and Metabolism, Graduate School of Biomedical Sciences, Hiroshima University, Japan
| | - Shiro Oka
- Department of Gastroenterology and Metabolism, Graduate School of Biomedical Sciences, Hiroshima University, Japan
| | - Shinji Tanaka
- Department of Endoscopy and Medicine, Hiroshima University Hospital, Japan
| | - Sumio Iio
- Department of Gastroenterology and Metabolism, Graduate School of Biomedical Sciences, Hiroshima University, Japan
| | - Ichiro Otani
- Department of Gastroenterology and Metabolism, Graduate School of Biomedical Sciences, Hiroshima University, Japan
| | - Sayoko Kunihara
- Department of Gastroenterology and Metabolism, Graduate School of Biomedical Sciences, Hiroshima University, Japan
| | - Kazuaki Chayama
- Department of Gastroenterology and Metabolism, Graduate School of Biomedical Sciences, Hiroshima University, Japan
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Color masking improves classification of celiac disease in videocapsule endoscopy images. Comput Biol Med 2019; 106:150-156. [DOI: 10.1016/j.compbiomed.2018.12.011] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2018] [Revised: 12/10/2018] [Accepted: 12/18/2018] [Indexed: 02/06/2023]
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Aasen TD, Wilhoite D, Rahman A, Devani K, Young M, Swenson J. No significant difference in clinically relevant findings between Pillcam ® SB3 and Pillcam ® SB2 capsules in a United States veteran population. World J Gastrointest Endosc 2019; 11:124-132. [PMID: 30788031 PMCID: PMC6379749 DOI: 10.4253/wjge.v11.i2.124] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/27/2018] [Revised: 01/20/2019] [Accepted: 01/26/2019] [Indexed: 02/06/2023] Open
Abstract
BACKGROUND Capsule endoscopy (CE) allows for a non-invasive small bowel evaluation for a wide range of gastrointestinal (GI) symptoms and diseases. Capsule technology has been rapidly advancing over recent years, often improving image frequency and quality. The Pillcam® SB3 (SB3) capsule is one such technology that offers an adaptive frame rate advantage over the previous versions of the capsule the Pillcam® SB2 (SB2). Some have proposed that this improvement in capsule technology may lead to increased diagnostic yields; however, real world clinical data is currently lacking.
AIM To evaluate the clinically relevant findings of SB3 and SB2 capsules in a population of United States veterans.
METHODS A retrospective analysis of 260 consecutive CE studies was performed including 130 SB3 and 130 SB2 capsule studies. Recorded variables included: age, gender, type of capsule, body mass index, exam completion, inpatient status, opioid use, diabetes, quality of preparation, gastric transit time, small bowel transit time, indication, finding, and if the exam resulted in a change in clinical management. The primary outcome measured was the detection of clinically relevant findings between SB3 and SB2 capsules.
RESULTS Mean age of the study population was 67.1 ± 10.4 years and 94.2% of patients were male. Of these 28.1% were on opioid users. The most common indications for capsule procedure were occult GI bleeding (74.6%) and overt GI bleeding (14.6%). Rates of incomplete exam were similar between SB3 and SB2 groups (16.9% vs 9.2%, P = 0.066). The overall rate of clinically relevant finding was 48.9% in our study. No significant difference was observed in SB3 vs SB2 capsules for clinically relevant findings (46.2% vs 51.5%, P = 0.385) or change in clinical management (40.8% vs 50.0%, P = 0.135).
CONCLUSION Our study found no significant difference in clinically relevant findings between SB3 and SB2 capsules.
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Affiliation(s)
- Tyler D Aasen
- Gastroenterology Section, East Tennessee State University Quillen College of Medicine, Johnson City, TN 37604, United States
| | - David Wilhoite
- Gastroenterology Section, East Tennessee State University Quillen College of Medicine, Johnson City, TN 37604, United States
| | - Aynur Rahman
- Gastroenterology Section, East Tennessee State University Quillen College of Medicine, Johnson City, TN 37604, United States
| | - Kalpit Devani
- Gastroenterology Section, East Tennessee State University Quillen College of Medicine, Johnson City, TN 37604, United States
| | - Mark Young
- Gastroenterology Section, East Tennessee State University Quillen College of Medicine, Johnson City, TN 37604, United States
| | - James Swenson
- Gastroenterology Section, Mountain Home Veterans Affairs Healthcare System, Mountain Home, TN 37684, United States
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Nam SJ, Kim JH, Park SC. The Usefulness of New-Generation Capsule Endoscopy in Patients with Portal Hypertensive Enteropathy. Clin Endosc 2018; 51:505-507. [PMID: 30449077 PMCID: PMC6283760 DOI: 10.5946/ce.2018.165] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/03/2018] [Accepted: 10/31/2018] [Indexed: 11/14/2022] Open
Affiliation(s)
- Seung-Joo Nam
- Division of Gastroenterology and Hepatology, Department of Internal Medicine, Kangwon National University School of Medicine, Chuncheon, Korea
| | - Ji Hyun Kim
- Division of Gastroenterology and Hepatology, Department of Internal Medicine, Kangwon National University School of Medicine, Chuncheon, Korea
| | - Sung Chul Park
- Division of Gastroenterology and Hepatology, Department of Internal Medicine, Kangwon National University School of Medicine, Chuncheon, Korea
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