Risk factors of delayed upper gastrointestinal transit in capsule endoscopy.

OBJECTIVE: The purpose was to investigate the risk factors for delayed upper gastrointestinal transit (DUGT) in small bowel capsule endoscopy (SBCE) and to improve the efficacy of SBCE. METHODS: The medical records of patients who underwent SBCE in Renji hospital between January 2015 and January 2023 were retrospectively reviewed. Data collection included patient demographics and potential risk factors for DUGT such as indications for the examination, underlying diseases, hospitalization status, anemia, inflammation. Risk factors were analyzed using univariable and multivariable logistic regression models. DUGT was defined as failure of a capsule to pass through the pylorus within 1 h. RESULTS: A total of 1459 patients who underwent SBCE were included in the study. 306 Cases (21%) experienced DUGT and all received conservative observation, medication treatment, endoscopic intervention, and other measures based on specific circumstances. The overall completion rate (CR) of the examination was 95.5% (1394/1459). Logistic regression analysis showed that hospitalization status (p = 0.030), diarrhea (p = 0.017), diabetes (p = 0.027) and cerebrovascular disease (p = 0.038) were significant risk factors for DUGT. CONCLUSIONS: In our study, DUGT of SBCE was associated with hospitalization status, diarrhea, diabetes and cerebrovascular disease. Therefore, for the patients with the above risk factors, we should closely check the capsule status during the examination process, in order to take appropriate intervention measures as soon as possible.

Reading of small bowel capsule endoscopy after frame reduction using an artificial intelligence algorithm.

OBJECTIVES: Poorly visualized images that appear during small bowel capsule endoscopy (SBCE) can confuse the interpretation of small bowel lesions and increase the physician's workload. Using a validated artificial intelligence (AI) algorithm that can evaluate the mucosal visualization, we aimed to assess whether SBCE reading after the removal of poorly visualized images could affect the diagnosis of SBCE. METHODS: A study was conducted to analyze 90 SBCE cases in which a small bowel examination was completed. Two experienced endoscopists alternately performed two types of readings. They used the AI algorithm to remove poorly visualized images for the frame reduction reading (AI user group) and conducted whole frame reading without AI (AI non-user group) for the same patient. A poorly visualized image was defined as an image with < 50% mucosal visualization. The study outcomes were diagnostic concordance and reading time between the two groups. The SBCE diagnosis was classified as Crohn's disease, bleeding, polyp, angiodysplasia, and nonspecific finding. RESULTS: The final SBCE diagnoses between the two groups showed statistically significant diagnostic concordance (k = 0.954, p < 0.001). The mean number of lesion images was 3008.5 ± 9964.9 in the AI non-user group and 1401.7 ± 4811.3 in the AI user group. There were no cases in which lesions were completely removed. Compared with the AI non-user group (120.9 min), the reading time was reduced by 35.6% in the AI user group (77.9 min). CONCLUSIONS: SBCE reading after reducing poorly visualized frames using the AI algorithm did not have a negative effect on the final diagnosis. SBCE reading method integrated with frame reduction and mucosal visualization evaluation will help improve AI-assisted SBCE interpretation.

Prolonged video capsule endoscopy examination durations can improve capsule endoscopy completeness.

BACKGROUND: Capsule endoscopy (CE) is useful for managing patients with suspected small bowel diseases. However, the effect of prolonged CE examination time on CE performance is unknown. AIM: To evaluate the completeness and diagnostic yield of prolonged CE imaging in patients with suspected small bowel bleeding. METHODS: We reviewed consecutive records of adult CE examinations via an overnight protocol from Jan 2016 to Dec 2020 at a tertiary center in Taiwan. We subcategorized the CE records by recording length into within 8 h, within 12 h and throughout the whole procedure and compared the completion rate and diagnostic yield between the groups. Cochran's Q test was used for statistical analysis. RESULTS: A total of 88 patients were enrolled with 78.4% inpatients (median age 72 years). The small bowel evaluation completion rate was 93.2%, which was significantly greater than the 79.5% rate within 12 h (p = 0.025) and the 58% rate within 8 h (p < 0.001). The diagnostic yield was 83% in the whole-course overnight study, which was significantly greater than the 71.6% diagnostic yield within 8 h (p < 0.001) and similar to the 81.8% diagnostic yield within 12 h. CONCLUSION: Prolonged overnight CE examination can improve the completion rate and diagnostic yield and should be considered for routine clinical practice.

Positioning exercises in improving the quality of magnetic-controlled capsule endoscopy.

BACKGROUND: Good gastric preparation is indispensable for Magnetic-controlled Capsule Endoscopy (MCE) examination, but there is no consensus yet. We aim to explore the clinical application value of positioning exercises in improving the quality of MCE examination. METHODS: Clinical data of 326 patients who underwent MCE examination from January 2020 to December 2023 were collected. The included patients were divided into two groups: the conventional medication preparation group (CMP group, accepted mucosal cleansing medication only) and the positioning exercises group (PE group, accepted mucosal cleansing medication plus positioning exercises). A comparison was made between the two groups in terms of gastric cavity cleanliness score, visibility score, and detection rate of positive lesions. RESULTS: The examination time was (21.29 ± 5.82) minutes in the PE group and (30.54 ± 6.37) minutes in the CMP group, showing a significant difference between the two groups (P < 0.001). The total cleanliness score and visibility score in the CMP group were 15.89 ± 2.82 and 10.93 ± 2.12, respectively. In contrast, the total cleanliness score and visibility score in the PE group were 19.52 ± 2.26 and 15.09 ± 2.31, respectively. The PE group showed significantly better cleanliness scores and visibility scores in all six anatomical regions compared to the CMP group (All P < 0.001). However, there was no significant difference in the detection rate of positive lesions between the two groups (All P > 0.05). CONCLUSION: Positioning exercises before MCE examination can improve the quality of gastric mucosal images and reduce the duration of the examination for patients.

Diagnostic accuracy of multimodal noninvasive follow-up for pediatric ulcerative colitis: A single-center prospective study.

OBJECTIVES: Ulcerative colitis (UC) is a chronic inflammatory bowel disease (IBD) often requiring endoscopic evaluations, which can be uncomfortable and costly, especially for children. This study aimed to evaluate the diagnostic accuracy of a noninvasive approach combining fecal calprotectin (FCP), colonic ultrasonography (US), and colon capsule endoscopy (CCE) compared with standard ileocolonoscopy in pediatric UC. METHODS: UC children were enrolled and underwent FCP and US on Day 0, followed by CCE on Day 1 and ileocolonoscopy on Day 2. All procedures were performed by operators who were blinded to the patient's clinical history and all test results. The accuracy for disease activity and extension of each technique and their combination was assessed and compared. Tolerability and safety were also evaluated. RESULTS: Thirty-two patients were enrolled (15 males, mean age 13.2 ± 3.2 years). CCE showed a sensitivity of 95% and specificity of 100% in detecting colonic inflammation, with positive predictive value (PPV) and negative predictive value (NPV) of 100% and 92%, respectively. US demonstrated a sensitivity of 85% and specificity of 92%, with PPV and NPV of 94% and 79%. The combination of FCP, US, and CCE achieved 95% sensitivity and 100% specificity, with PPV of 100% and NPV of 92%. The noninvasive approach was better tolerated than colonoscopy (p < 0.05), and no serious adverse events were reported. CONCLUSION: The noninvasive approach combining fecal calprotectin (FCP), ultrasonography, and colon capsule endoscopy demonstrated high diagnostic accuracy and better tolerability compared with standard ileocolonoscopy in pediatric ulcerative colitis follow-up. Further multicenter studies are needed to confirm these findings and evaluate the reproducibility of this noninvasive approach.

Long-term outcomes of patients with obscure gastrointestinal bleeding after negative capsule endoscopy.

BACKGROUND AND AIM: Although small-bowel capsule endoscopy (CE) is widely used for obscure gastrointestinal bleeding (OGIB), long-term outcomes for OGIB patients after negative CE remain unclear. Herein, we defined negative CE as P0 (no bleeding potential) or P1 (less likely to bleed), based on the P classification using CE. We aimed to clarify long-term outcomes of patients with OGIB after negative CE. METHODS: This single-center observational study enrolled 461 consecutive patients with OGIB who underwent CE from March 2014 to October 2021 and were followed up for >1 year. We examined rebleeding rates and predictive factors. RESULTS: Two hundred and twenty-four (49%) patients had P0, and 237 (51%) had P1 findings. Rebleeding occurred in 9% and 16% of patients in the P0 and P1 groups, respectively. Two patients in the P0 group and 15 in the P1 group showed rebleeding from the small bowel. The rate of small-bowel rebleeding was significantly lower in the P0 group than that in the P1 group (1% vs 6%, P = 0.002), as was the cumulative rebleeding rate (P = 0.004). In the multivariate analysis, history of endoscopic hemostasis (hazard ratio [HR] = 15.958, 95% confidence interval [CI]:4.950-51.447, P < 0.001) and P1 CE findings (HR = 9.989, 95% CI: 2.077-48.030, P = 0.004) were independently predicted small-bowel rebleeding. CONCLUSIONS: OGIB with P0 CE findings rarely showed rebleeding from the small bowel. Rebleeding may occur in patients with OGIB. Patients with history of endoscopic hemostasis for small-bowel lesions or P1 CE findings should be followed up intensively.

Comparison of clinical utility of deep learning-based systems for small-bowel capsule endoscopy reading.

BACKGROUND AND AIM: Convolutional neural network (CNN) systems that automatically detect abnormalities from small-bowel capsule endoscopy (SBCE) images are still experimental, and no studies have directly compared the clinical usefulness of different systems. We compared endoscopist readings using an existing and a novel CNN system in a real-world SBCE setting. METHODS: Thirty-six complete SBCE videos, including 43 abnormal lesions (18 mucosal breaks, 8 angioectasia, and 17 protruding lesions), were retrospectively prepared. Three reading processes were compared: (A) endoscopist readings without CNN screening, (B) endoscopist readings after an existing CNN screening, and (C) endoscopist readings after a novel CNN screening. RESULTS: The mean number of small-bowel images was 14 747 per patient. Among these images, existing and novel CNN systems automatically captured 24.3% and 9.4% of the images, respectively. In this process, both systems extracted all 43 abnormal lesions. Next, we focused on the clinical usefulness. The detection rates of abnormalities by trainee endoscopists were not significantly different across the three processes: A, 77%; B, 67%; and C, 79%. The mean reading time of the trainees was the shortest during process C (10.1 min per patient), followed by processes B (23.1 min per patient) and A (33.6 min per patient). The mean psychological stress score while reading videos (scale, 1-5) was the lowest in process C (1.8) but was not significantly different between processes B (2.8) and A (3.2). CONCLUSIONS: Our novel CNN system significantly reduced endoscopist reading time and psychological stress while maintaining the detectability of abnormalities. CNN performance directly affects clinical utility and should be carefully assessed.

Liver transplant for primary biliary tract neuroendocrine tumor in a nine-year-old girl.

BACKGROUND: Neuroendocrine tumors (NETs) are rare epithelial neoplasms that arise most commonly from the gastrointestinal tract. In pediatrics, the most common site of origin is in the appendix, with the liver being the most common site of metastasis. Neuroendocrine tumors arising from the biliary tract are extremely rare. METHODS: We describe a case of a nine-year-old girl who presented with obstructive cholestasis and was found to have multiple liver masses identified on biopsy as well-differentiated neuroendocrine tumor with an unknown primary tumor site. RESULT: The patient underwent extensive investigation to identify a primary tumor site, including endoscopy, endoscopic ultrasound, and capsule endoscopy. The patient ultimately underwent definitive management with liver transplant, and on explant was discovered to have multiple well-differentiated neuroendocrine tumors, WHO Grade 1, with extensive infiltration into the submucosa of bile duct, consistent with primary biliary tract neuroendocrine tumor. CONCLUSION: Identifying the site of the primary tumor in NETs found within the liver can be challenging. To determine if an extrahepatic primary tumor exists, workup should include endoscopy, EUS, and capsule endoscopy. Children with well-differentiated hepatic NETs, with no identifiable primary tumor, and an unresectable tumor, are considered favorable candidates for liver transplantation.

Implantable antennas for biomedical applications: a systematic review.

This review presents an in-depth examination of implantable antennas for various biomedical purposes. The development of implantable antennas, including their designs, materials, and operating principles, are introduced at the beginning of the discussion. An overview of the many kinds of implantable antennas utilized in implantable medical devices (IMDs) are presented in this study. The article then discusses the important factors to consider when developing implantable antennas for biomedical purposes, including implant placement, frequency range, and power needs. This investigation additionally examines the challenges and limitations encountered with implantable antennas, including the limited space available within the human body, the requirement for biocompatible materials, the impact of surrounding tissue on antenna performance, tissue attenuation, and signal interference. This review also emphasizes the most recent advances in implanted antenna technology, such as wireless power transmission, multiband operation, and miniaturization. Furthermore, it offers illustrations of several biomedical uses for implantable antennas, including pacemaker, capsule endoscopy, intracranial pressure monitoring, retinal prostheses, and bone implants. This paper concludes with a discussion of the future of implantable antennas and their possible use in bioelectronic medicine and novel medical implants. Overall, this survey offers a thorough analysis of implantable antennas in biomedical applications, emphasizing their importance in the development of implantable medical technology.

A Novel Method to Localize Patency Capsule by Ileocolonoscopy Facilitates Endoscopic Assessment of the Small and Large Intestine in Patients with Crohn's Disease.

INTRODUCTION: Patients with Crohn's disease (CD) require an assessment of small bowel lesions, while difficulties exist in performing small intestinal examinations, especially in small-sized medical offices. Small bowel capsule endoscopy (SBCE) is handy and can be performed in most clinical settings. The only drawback of SBCE is a requirement of patency testing prior to the exam because it sometimes requires CT scanning to localize the ingested patency capsule (PC), which may be a substantial burden for the patient. We have developed a novel PC detection system named PICS (patency capsule, ileocolonoscopy, and small bowel capsule endoscopy) method by which we can avoid CT scanning. In the PICS method, ileocolonoscopy (ICS) is performed after 30-33 h of PC ingestion and the PC can be localized by ICS in patients who have not excreted the PC, and the entire intestine can be examined in combination with subsequent SBCE without additional bowel preparation. The aim of this study was to assess the usefulness and safety of the PICS method for CD patients. METHODS: CD patients who underwent PICS method from April 2021 to March 2023 were reviewed for clinical data, outcome of PICS method including the rates of PC detection by ICS, the number of patients underwent SBCE, and adverse events. Lewis score was used to assess SBCE results. RESULTS: The PICS method was performed in 54 patients. The median age of patients was 28.5 years old, and 64.8% of them were ileocolic type. The median disease duration was 10.5 months and 24.1% had history of small bowel resection. Five cases (9.3%) confirmed gastrointestinal patency by ICS, and none of the cases required CT scanning. One patient who could not be confirmed patency by ICS, and the other patient who excreted PC but was found ileal stenosis by ICS did not undergo SBCE. Remaining 52 patients received SBCE, and the median Lewis score of them was 0 (IQR 0, 450). There were no adverse events including small bowel obstruction by PC and SBCE retention in this series. CONCLUSION: The PICS method is not only feasible and safe but also convenient to assess disease extent in patients with CD. By localizing PC with ICS, additional CT scanning could be unnecessary for SBCE, which benefits both physicians and CD patients.

Long-Term Monitoring and Clinical Implications of Small Bowel Capsule Endoscopy in Patients with Crohn's Disease with Small Bowel Lesions: A Retrospective Analysis.

INTRODUCTION: Crohn's disease (CD) induces persistent inflammation throughout the gastrointestinal (GI) tract, potentially resulting in complications such as intestinal stenosis and fistulas, particularly in the small bowel. Small bowel capsule endoscopy (SBCE) is recommended for monitoring CD, especially when GI tract patency is maintained. This study aimed to retrospectively assess patients with CD who underwent SBCE to determine the timing of clinical changes and address the current lack of evidence regarding GI tract patency loss during CD treatment. METHODS: Of the 166 consecutive patients who underwent SBCE at our institution, 120 were followed up and included in this study. Forty-six patients were excluded due to colitis type or immediate treatment changes post-SBCE. This study focused on the primary and secondary endpoints, including the cumulative stricture-free rate of the GI tract, emergency hospitalization post-SBCE, and post-SBCE treatment strategies, at the discretion of the attending physicians. RESULTS: Demographic data revealed that the mean age of the study population was 43 years and that there was a male predominance (75%). The median disease duration was 12 years and the mean Crohn's Disease Activity Index was 98. During a 1,486-day observation period, 37% of patients experienced treatment changes. A Lewis score of >264 and perianal lesions were identified as independent risk factors for additional treatment needs. Emergency hospitalization occurred in 6% of patients and GI patency failure in 11%. Female sex and Lewis score>264 were associated with higher risks. GI patency rate declined 2 years after SBCE. CONCLUSIONS: For patients who experienced no treatment changes based on SBCE results, it is recommended to undergo SBCE monitoring at intervals of no longer than 2 years.

Patients on Antithrombotic Agents with Small Bowel Bleeding -Yield of Small Bowel Capsule Endoscopy and Subsequent Management.

BACKGROUND AND AIMS: Small bowel gastrointestinal bleeding (GIB) is associated with multiple blood transfusions, prolonged and/or multiple hospital admissions, utilization of significant healthcare resources, and negative effects on patient quality of life. There is a well-recognized association between antithrombotic medications and small bowel GIB. We aimed to identify the diagnostic yield of small bowel capsule endoscopy (SBCE) in patients on antithrombotic medications and the impact of SBCE on treatment course. METHODS: The electronic medical records of nineteen hundred eighty-six patients undergoing SBCE were retrospectively reviewed. RESULTS: The diagnostic yield for detecting stigmata of recent bleeding and/or actively bleeding lesions in SBCE was higher in patients that were on antiplatelet agents (21.6%), patients on anticoagulation (22.5%), and in patients that had their SBCE performed while they were inpatient (21.8%), when compared to the patients not on antiplatelet agents (12.1%), patients not on anticoagulation (13.5%), and with patients that had their SBCE performed in the outpatient setting (12%). Of 318 patients who had stigmata of recent bleeding and/or actively bleeding lesion(s) identified on SBCE, SBCE findings prompted endoscopic evaluation (small bowel enteroscopy, esophagogastroduodenoscopy (EGD), and/or colonoscopy) in 25.2%, with endoscopic hemostasis attempted in 52.5%. CONCLUSIONS: Our study, the largest conducted to date, emphasizes the importance of performing SBCE as part of the evaluation for suspected small bowel bleeding, particularly in patients taking antithrombotic therapy, and especially during their inpatient hospital stay.

Examining the Impact of a GI Hospitalist Model on the Outcomes of Double-Balloon Enteroscopy: A Single-Center Retrospective Study.

BACKGROUND: A GI hospitalist (GIH) is a physician who practices in the inpatient setting performing consultations and endoscopic procedures. Obscure small bowel bleeding is a common inpatient diagnosis that is difficult to manage and associated with longer hospitalizations. Having an onsite GIH physician with expertise in video capsule endoscopy (VCE) and double-balloon enteroscopy (DBE) has the potential to improve patient outcomes. AIMS: This study will be the first to explore how implementing a GIH model and providing a GIH with training in DBE can affect the outcomes of patients with small bowel pathology. METHODS: We performed a retrospective study of patients who received an inpatient DBE at an academic medical center before and after initiation of a GIH model and credentialing of a GIH in DBE. We compared outcomes, including procedure volumes, diagnostic and therapeutic yields, procedure duration, time to procedure, and length of stay. RESULTS: There was a 46.5% increase in the number of DBEs performed by the GIH. The diagnostic yield increased from 56.3 to 74.0% (OR 2.2, 95% CI 1.2-4.2), and the proportion of DBEs with a therapeutic intervention increased from 38.0 to 65.4% (OR 3.1, 95% CI 1.4-7.0). The total procedure time increased from 77.8 to 96.4 min (p < 0.05) with a GIH. CONCLUSION: Having a GIH perform inpatient DBEs was associated with an increased number of procedures, duration of procedures, diagnostic yield, and therapeutic interventions. The onsite presence of a GIH with competency in DBE improves the care of hospitalized patients with small bowel pathology.

Yield of capsule endoscopy and subsequent device-assisted enteroscopy: experience at an Australian tertiary centre.

BACKGROUND: Small bowel capsule endoscopy (SBCE) and device-assisted enteroscopy (DAE) have an established role in the investigation and management of small bowel pathology. Previous studies have reported on the yield of SBCE (60%) and DAE (57%), but none have been in an Australian setting. AIMS: To determine the yield of SBCE and any DAE performed as a direct consequence of SBCE in an Australian referral centre. METHODS: A single-centre retrospective study was conducted at a tertiary hospital in Australia, enrolling consecutive patients between 1 January 2009 and 31 December 2021 undergoing SBCE. Data were collected with respect to demographics, procedural factors and findings, as well as findings and interventions of any DAE procedures performed after the SBCE. RESULTS: 1214 SBCEs were performed, with a median age of 66 years old (60.8% men). The predominant indications were anaemia (n = 853, 70.2%) and overt gastrointestinal bleeding (n = 320, 26.4%). Of the complete small bowel studies (1132/1214, 93.2%), abnormal findings were detected in 588 cases (51.9%), most commonly angioectasias (266/588, 45.2%), erosions (106/588, 18.0%) and ulcers (97/588, 8.6%). 165 patients underwent a DAE (117 antegrade, 48 retrograde). Antegrade DAE had a higher yield than retrograde DAE (77.8% vs 54.2%; P = 0.002) and a higher rate of intervention (69.2% vs 37.5%; P < 0.001). CONCLUSION: In this largest single-centre cohort of patients undergoing SBCE to date, there is a similar yield of abnormal findings compared to existing literature. DAE, especially with an antegrade approach, had high diagnostic and therapeutic yield when pursued after a positive SBCE study.

Deep learning in negative small-bowel capsule endoscopy improves small-bowel lesion detection and diagnostic yield.

OBJECTIVES: Although several studies have shown the usefulness of artificial intelligence to identify abnormalities in small-bowel capsule endoscopy (SBCE) images, few studies have proven its actual clinical usefulness. Thus, the aim of this study was to examine whether meaningful findings could be obtained when negative SBCE videos were reanalyzed with a deep convolutional neural network (CNN) model. METHODS: Clinical data of patients who received SBCE for suspected small-bowel bleeding at two academic hospitals between February 2018 and July 2020 were retrospectively collected. All SBCE videos read as negative were reanalyzed with the CNN algorithm developed in our previous study. Meaningful findings such as angioectasias and ulcers were finally decided after reviewing CNN-selected images by two gastroenterologists. RESULTS: Among 202 SBCE videos, 103 (51.0%) were read as negative by humans. Meaningful findings were detected in 63 (61.2%) of these 103 videos after reanalyzing them with the CNN model. There were 79 red spots or angioectasias in 40 videos and 66 erosions or ulcers in 35 videos. After reanalysis, the diagnosis was changed for 10 (10.3%) patients who had initially negative SBCE results. During a mean follow-up of 16.5 months, rebleeding occurred in 19 (18.4%) patients. The rebleeding rate was 23.6% (13/55) for patients with meaningful findings and 16.1% (5/31) for patients without meaningful findings (P = 0.411). CONCLUSION: Our CNN algorithm detected meaningful findings in negative SBCE videos that were missed by humans. The use of deep CNN for SBCE image reading is expected to compensate for human error.

Clinical application and feasibility of capsule endoscopy in children at a medical center in central Taiwan.

BACKGROUND PURPOSE: Capsule endoscopy (CE) is a noninvasive examination for excellent visualization of small bowel mucosal lesions. We aimed to evaluate the clinical efficacy and safety of CE in pediatric patients. METHODS: From April 2014 to December 2022, CE procedures performed in children younger than 18 years of age at Taichung Veteran General Hospital were analyzed retrospectively. RESULTS: Among 136 procedures, the completion rate was 95.6% (n = 130), with a median age of 14 years old. Suspicion or evaluation of inflammatory bowel diseases (IBD) (41%) was the most common indication for CE. Other common indications of CE were chronic unexplained abdominal pain (35%) and obscure gastrointestinal bleeding or iron deficiency anemia (21%). No procedure-related complications occurred. The diagnosis of those patients with incomplete study were CD with small bowel stricture, graft-versus-host disease and duodenal ulcers. A total of 86 CE procedures showed positive findings, and the overall diagnostic yield rate was 63.2%. Small bowel ulcers (65.12%) were the most common findings. Overall, 26.5% of CE examinations resulted in a new diagnosis and 44.9% of CE exams led to a change in therapy. For patients with IBD, CE findings resulted in an even higher therapeutic change rate of 48.1%. CONCLUSIONS: CE is a safe and feasible diagnostic method to study the small intestine in children, especially for IBD. Incomplete study could be an indicator of positive finding and can potentially be a guide to identify the site of possible strictures.

Design of a Compact Circularly Polarized Implantable Antenna for Capsule Endoscopy Systems.

This research proposes a miniature circular polarization antenna used in a wireless capsule endoscopy system at 2.45 GHz for industrial, scientific, and medical bands. We propose a method of cutting a chamfer rectangular slot on a circular radiation patch and introducing a curved radiation structure into the centerline position of the chamfer rectangular slot, while a short-circuit probe is added to achieve miniaturization. Therefore, we significantly reduced the size of the antenna and made it exhibit circularly polarized radiation characteristics. A cross-slot is cut in the GND to enable the antenna to better cover the operating band while being able to meet the complex human environment. The effective axis ratio bandwidth is 120 MHz (2.38-2.50 GHz). Its size is π × 0.032λ02 × 0.007λ0 (where λ0 is the free-space wavelength of at 2.4 GHz). In addition, the effect of different organs such as muscle, stomach, small intestine, and big intestine on the antenna when it was embedded into the wireless capsule endoscopy (WCE) system was further discussed, and the results proved that the WCE system has better robustness in different organs. The antenna's specific absorption rate can follow the IEEE Standard Safety Guidelines (IEEE C95.1-1999). A prototype is fabricated and measured. The experimental results are consistent with the simulation results.

Search for small-bowel capsule diagnostic yield optimization conducted through observational analysis. / Búsqueda de optimización de la cápsula endoscópica mediante análisis observacional.

OBJECTIVES: To search for parameters susceptible to optimization when performing capsule endoscopy (CE) in a third level hospital with high volume and experience in this test. PATIENTS AND METHODS: Retrospective observational study, including 1325 CEs performed between 2017 and 2022. Overall diagnostic yield, effective diagnostic yield, by indication, place of request and waiting list, as well as complete examination rate and cleansing degree were analyzed. RESULTS: The overall diagnostic yield was 70.99%, while the effective diagnostic yield was 72.7%. Diagnostic yields varied between 60.2% and 77.9% depending on the indication and between 64.7% and 74.3% depending on the requesting center. The mean waiting list was 101.15 days, with a tendency to worse results when the waiting list was longer. A total of 77.8% of the examinations were complete. Completion rates were lower in patients >70 years of age (p=0.001), as well as in those with gastric transit >60minutes (p=0.000). A total of 77.3% were clean, with debris that did not impede diagnosis being found in 16.9% and debris that did impede diagnosis in 5.8%. There was a relationship, although not significant, between cleansing degree and age. CONCLUSIONS: The diagnostic yields of CE in our center are in line with those previously reported. Differences were found according to the place of request. Waiting list could also influence diagnostic yield. Completion rates are lower in >70 years of age and when gastric transit is >60minutes. Cleansing degree achieved is acceptable.

Small bowel Crohn's disease: Proximal lesions linked to increased inflammation and biologic treatment needs.

OBJECTIVE: Crohn's disease (CD) is heterogeneous, and proximal involvement in the small bowel (SB) is associated with worse outcomes. Nonetheless, studies on the impact of duodenal and jejunal lesions in SB CD are limited. This study aimed to investigate the clinical characteristics and outcomes of individuals diagnosed with SB CD, comparing those with and without proximal inflammation. METHODS: A cohort of 53 treatment-naive SB CD patients that underwent Capsule Endoscopy at diagnosis were retrospectively selected. The inflammatory activity was quantified using the Lewis Score for each SB tertile. RESULTS: Thirty-seven (69.8%) patients displayed inflammatory activity in the first and/or second tertile together with third tertile involvement (Proximal+T3 group). Sixteen (30.2%) had inflammation in the third tertile only (T3 group). Individuals in the Proximal+T3 group had a higher risk for moderate-to-severe inflammation (OR 4.93, 95% CI: 1.3-18.3, p=0.013). A subgroup analysis for those with mild inflammatory activity showed that individuals in the Proximal+T3 group initiated biologic drugs more often (OR 11, 95% CI: 1.1-109.7, p=0.036). CONCLUSION: Proximal SB lesions are associated with increased inflammatory activity, necessitating more frequent use of biologics in patients with mild disease. Early detection of proximal SB CD with Capsule Endoscopy may contribute to timely treatment.

Endoscopic Advances in the Diagnosis and Management of Gastroesophageal Reflux Disease.

Gastroesophageal reflux disease (GERD) is one of the most common diseases that occurs secondary to failure of the antireflux barrier system, resulting in the frequent and abnormal reflux of gastric contents to the esophagus. GERD is diagnosed in routine clinical practice based on the classic symptoms of heartburn and regurgitation. However, a subset of patients with atypical symptoms can pose challenges in diagnosing GERD. An esophagogastroduodenoscopy (EGD) is the most common initial diagnostic test used in the assessment for GERD, although half of these patients will not have any positive endoscopic findings suggestive of GERD. The advanced endoscopic techniques have improved the diagnostic yield of GERD diagnosis and its complications, such as Barrett's esophagus and early esophageal adenocarcinoma. These newer endoscopic tools can better detect subtle irregularities in the mucosa and vascular structures. The management options for GERD include lifestyle modifications, pharmacological therapy, and endoscopic and surgical interventions. The latest addition to the armamentarium is the minimally invasive endoscopic interventions in carefully selected patients, including the electrical stimulation of the LES, Antireflux mucosectomy, Radiofrequency therapy, Transoral Incisionless Fundoplication, Endoscopic Full-Thickness plication (GERDx™), and suturing devices. With the emergence of these advanced endoscopic techniques, it is crucial to understand their selection criteria, advantages, and disadvantages.