Rotational Platform for Real-Time Localization for Active Implantable Medical Devices.

This paper presents a sensor based localization system to localize active implantable medical devices i.e., Wireless Capsule Endoscopy (WCE). The importance of localizing the capsule arises once the images from the capsule detect the abnormalities in the Gastrointestinal tract (GI). A successful system can determine the location that associated with the abnormality for further medical investigation or treatment. The system proposed in this paper comprises a rotational platform that consists of magnetic sensors to detect the position of the embedded magnet in the capsule. The rotational platform provides advantageousness in terms of reducing the number of the sensors and increasing the monitoring accuracy during the real time movement.

Dieulafoy’s lesion in the cecal pole diagnosed by video-capsule endoscopy. A rare cause of lower gastrointestinal bleeding / Lesión de Dieulafoy en el cecal polo diagnosticado por videocápsula endoscopia. Una causa rara de sangrado gastrointestinal bajo

Dieulafoy's lesion is a rare vascular malformation that can cause massive acute gastrointestinal hemorrhage threatening the patient's life. This correspondence to the editor outlines the clinical presentation of a patient in whom, owing to the utilization of capsule endoscopy followed by subsequent colonoscopy, a diagnosis of hemorrhage resulting from a Dieulafoy's lesion located in the colon, a relatively uncommon site, was successfully established. Following intervention involving the application of hemoclips, the patient experienced a favorable clinical evolution.(AU)

La cápsula endoscópica para el diagnóstico del melanoma intestinal / Cholecystogastric fistula diagnosed by endoscopic ultrasonography

Melanoma is a cancer that frequently metastasises to the small bowel, but most cases are asymptomatic and are diagnosed postmortem. Therefore, CT and PET CT cannot detect all lesions and conventional endoscopic study only detects 10-20% of lesions. In this study, we present the case of a 68-year-old patient with a history of cutaneous melanoma and a diagnosis of intestinal melanoma. Thanks to capsule endoscopy, two lesions compatible with cutaneous melanoma metastasis to the small bowel were detected, allowing a much more effective surgical planning. Capsule endoscopy is an innovative technique that improves preoperative diagnosis, as it is able to detect bowel segments that cannot be inspected by conventional endoscopy. It also has a better resolution than conventional CT, improving sensitivity in the detection of lesions.(AU)

Drug-induced entero-colitis due to interleukin-17 inhibitor use; capsule endoscopic findings and pathological characteristics: A case report.

BACKGROUND: Interleukin-17 (IL-17) inhibitors are known to cause exacerbation or new onset of inflammatory bowel disease upon administration. However, few reports have described characteristic endoscopic and histopathologic findings, and no small intestinal lesions have been reported so far. CASE SUMMARY: A woman in her 60s with psoriasis was administered ixekizumab (IXE), an anti-IL-17A antibody, for the treatment of psoriasis. Twenty months after commencing treatment, the patient visited our hospital because of persistent diarrhea. Blood tests performed at the time of the visit revealed severe inflammation, and colonoscopy revealed multiple round ulcers throughout the colon. A tissue biopsy of the ulcer revealed infiltration of inflammatory cells and granuloma-like findings in the submucosal layer. Capsule endoscopy revealed multiple jejunal erosions. After the withdrawal of IXE, the symptoms gradually improved, and ulcer reduction and scarring of the colon were endoscopically confirmed. CONCLUSION: To the best of our knowledge, 17 reports have documented IL-17 inhibitor-induced entero-colitis with endoscopic images, endoscopic findings, and pathological characteristics, including the present case. Nine of these cases showed diffuse loss of vascular pattern, coarse mucosa/ulcer formation in the left colon, and endoscopic findings similar to those of ulcerative colitis. In the remaining eight cases, discontinuous erosions and ulcerations from the terminal ileum to the rectum were seen, with endoscopic findings similar to those of Crohn's disease. In this case, the findings were confirmed by capsule endoscopy, which has not been previously reported.

Evaluating clinical diversity and plausibility of synthetic capsule endoscopic images.

Wireless Capsule Endoscopy (WCE) is being increasingly used as an alternative imaging modality for complete and non-invasive screening of the gastrointestinal tract. Although this is advantageous in reducing unnecessary hospital admissions, it also demands that a WCE diagnostic protocol be in place so larger populations can be effectively screened. This calls for training and education protocols attuned specifically to this modality. Like training in other modalities such as traditional endoscopy, CT, MRI, etc., a WCE training protocol would require an atlas comprising of a large corpora of images that show vivid descriptions of pathologies, ideally observed over a period of time. Since such comprehensive atlases are presently lacking in WCE, in this work, we propose a deep learning method for utilizing already available studies across different institutions for the creation of a realistic WCE atlas using StyleGAN. We identify clinically relevant attributes in WCE such that synthetic images can be generated with selected attributes on cue. Beyond this, we also simulate several disease progression scenarios. The generated images are evaluated for realism and plausibility through three subjective online experiments with the participation of eight gastroenterology experts from three geographical locations and a variety of years of experience. The results from the experiments indicate that the images are highly realistic and the disease scenarios plausible. The images comprising the atlas are available publicly for use in training applications as well as supplementing real datasets for deep learning.

Predictive value of patency capsule and magnetic resonance enterography for capsule endoscopy retention in patients with established Crohn’s disease

Introduction: retention is the most common adverse event of the small bowel capsule endoscopy procedure. Patency capsule (Medtronic, Dublin, Ireland) and magnetic resonance enterography are two diagnostic methods that can prevent small bowel capsule endoscopy retention. The aim of this study was to evaluate the predictive value of these two diagnostic methods. Material and methods: a prospective, comparative and observational study was performed in patients with established Crohn’s disease. All patients had undergone magnetic resonance enterography and patency capsule procedures. If the patency capsule was not retained, the patient underwent a small bowel capsule endoscopy; otherwise, double balloon enteroscopy was performed to locate the stenosis. Magnetic resonance enterography predictive criteria for retention were analyzed in all cases. Sensitivity, specificity, positive predictive value and negative predictive value of the patency capsule and magnetic resonance enterography compared to small bowel capsule endoscopy or double balloon enteroscopy were calculated. Results: forty patients were included (24 female, 55 ± 13 years old). Retention criteria with capsule endoscopy or double balloon enteroscopy were found in six patients, agreeing in five cases with patency capsule and in three cases with magnetic resonance enterography. Sensitivity, specificity, positive predictive value, negative predictive value and Kappa coefficient for predicting retention with the patency capsule were 83 %, 100 %, 100 % and 97 %, respectively, and 50 %, 91 %, 50 % and 91 %, respectively, with magnetic resonance enterography. Conclusions: patency capsule has a higher sensitivity and positive predictive value than magnetic resonance enterography for preventing small bowel capsule endoscopy retention in Crohn’s disease patients (AU)

Artificial intelligence and capsule endoscopy: automatic detection of enteric protruding lesions using a convolutional neural network

Background and aims: capsule endoscopy (CE) revolutionized the study of the small intestine. Nevertheless, reviewing CE images is time-consuming and prone to error. Artificial intelligence algorithms, particularly convolutional neural networks (CNN), are expected to overcome these drawbacks. Protruding lesions of the small intestine exhibit enormous morphological diversity in CE images. This study aimed to develop a CNN-based algorithm for the automatic detection small bowel protruding lesions. Methods: a CNN was developed using a pool of CE images containing protruding lesions or normal mucosa from 1,229 patients. A training dataset was used for the development of the model. The performance of the network was evaluated using an independent dataset, by calculating its sensitivity, specificity, accuracy, positive and negative predictive values. Results: a total of 18,625 CE images (2,830 showing protruding lesions and 15,795 normal mucosa) were included. Training and validation datasets were built with an 80 %/20 % distribution, respectively. After optimizing the architecture of the network, our model automatically detected small-bowel protruding lesions with an accuracy of 92.5 %. CNN had a sensitivity and specificity of 96.8 % and 96.5 %, respectively. The CNN analyzed the validation dataset in 53 seconds, at a rate of approximately 70 frames per second. Conclusions: we developed an accurate CNN for the automatic detection of enteric protruding lesions with a wide range of morphologies. The development of these tools may enhance the diagnostic efficiency of CE (AU)

Magnetic controlled capsule endoscope (MCCE)'s diagnostic performance for H. pylori infection status based on the Kyoto classification of gastritis.

BACKGROUND: Previous studies have shown that the Kyoto classification of gastritis can accurately predict H. pylori infection status on conventional gastroscopy. The aim of this study was to test whether the Kyoto classification of gastritis applies well to magnetic controlled capsule endoscopy (MCCE). METHODS: We consecutively recruited 227 participants who underwent both MCCE and urea breath tests (UBTs). Two physicians who were blinded to the UBT results independently made the diagnosis of H. pylori infection status according to 10 findings listed in the Kyoto classification of gastritis after reviewing MCCE images. We also developed 2 predictive models to assess H. pylori infection status by combining these 10 findings. RESULTS: The MCCE's overall diagnostic accuracy for H. pylori infection status was 80.2%. The sensitivity, specificity and diagnostic odds ratio (DOR) for current infection were 89.4%, 90.1% and 77.1, respectively. Major specific findings were mucosal swelling and spotty redness for current infection, regular arrangement of collecting venules (RAC), streak redness, fundic gland polyp (FGP) for noninfection, and map-like redness for past-infection. In the two prediction models, the area under the curve (AUC) values for predicting noninfection and current infection were 84.7 and 84.9, respectively. CONCLUSIONS: The Kyoto classification of gastritis applied well to MCCE. H. pylori infection status could be accurately assessed on MCCE according to the Kyoto classification of gastritis.

Linfangiectasia intestinal primaria: una enfermedad rara como causa de enteropatía pierde-proteínas / Primary intestinal lymphangiectasia: a rare disease as a cause of protein-losing enteropathy

La linfangiectasia intestinal primaria es un trastorno raro asociado a una enteropatía pierde-proteínas. Las principales manifestaciones son las derivadas de la hipoalbuminemia. Para lograr el diagnóstico se necesita la imagen endoscópica típica de la linfangiectasia intestinal y el aumento de las cifras de alfa-1-antitripsina en las heces de 24 horas. El tratamiento es básicamente dietético. (AU)

Predictive factors for inadequate bowel cleansing in colon capsule endoscopy / Factores predictores de limpieza colónica inadecuada en exploraciones con cápsula endoscópica de colon

Background and aims: Achieving adequate bowel cleansing is of utmost importance for the efficiency of colon capsule endoscopy (CCE). However, information about predictive factors is lacking. The aim of this study was to assess the predictive factors of poor bowel cleansing in the CCE setting. Methods: In this observational study, 126 patients who underwent CCE at two tertiary care hospitals were included between June 2017 and January 2020. Participants prepared for bowel cleansing with a 1-day clear liquid diet, a 4-L split-dose polyethylene glycol regimen and boosters with sodium phosphate, sodium amidotrizoate and meglumine amidotrizoate. Domperidone tablets and bisacodyl suppositories were administered when needed. Overall and per-segment bowel cleansing was evaluated using a CCE cleansing score. Simple and multiple logistic regression analysis were carried out to assess poor bowel cleansing and excretion rate predictors. Results: Overall bowel cleansing was optimal in 53 patients (50.5%). Optimal per-segment bowel cleansing was achieved as follows: cecum (86 patients; 74.8%), transverse colon (91 patients; 81.3%), distal colon (81 patients; 75%) and rectum (64 patients; 66.7%). In the univariate analysis, elderly (OR, 1.03; 95% CI (1.01–1.076)) and constipation (OR, 3.82; 95% CI (1.50–9.71)) were associated with poor bowel cleansing. In the logistic regression analysis, constipation (OR, 3.77; 95% CI (1.43–10.0)) was associated with poor bowel cleansing. No variables were significantly associated with the CCE device excretion rate. Conclusion: Our results suggest that constipation is the most powerful predictor of poor bowel cleansing in the CCE setting. Tailored cleansing protocols should be recommended for these patients.(AU)

Antecedentes y objetivos Lograr una limpieza intestinal adecuada es de gran importancia para la eficiencia de la cápsula endoscópica de colon (CEC). Se carece de información sobre factores predictivos. El objetivo fue evaluar los factores predictivos de la limpieza colónica deficiente en pacientes con CEC. Métodos: Ciento veintiséis pacientes fueron sometidos a CEC en dos hospitales de tercer nivel entre junio de 2017 y enero de 2020. La preparación consistió en un día de dieta líquida, y 4 l de polietilenglicol (dosis fraccionada), fosfato sódico, amidotrizoato de sodio y meglumina amidotrizoato. Ocasionalmente se administró domperidona y supositorios de bisacodilo. Se evaluó limpieza total y por segmentos. Se realizó un análisis de regresión logística simple y múltiple para evaluar factores de limpieza deficiente y de excreción de la CEC. Resultados: La limpieza intestinal fue óptima en 53 pacientes (50,5%). Por segmentos fue: ciego y ascendente (86 pacientes; 74,8%), transverso (91 pacientes; 81,3%), distal (81 pacientes; el 75%) y recto (64 pacientes; 66,7%). En la regresión simple, la edad avanzada (OR, 1,03, IC 95% [1,01-1,076]) y el estreñimiento (OR, 3,82; IC 95% [1,50-9,71]) se asociaron con una limpieza deficiente. El estreñimiento (OR, 3,77; IC del 95% [1,43-10,0]) fue el único factor asociado de forma independiente. Ninguna variable se asoció a la tasa de excreción de la CEC. Conclusión: Nuestros resultados sugieren que el estreñimiento es el factor más potente de la limpieza deficiente colónica en el estudio endoscópico con CEC. Protocolos de limpieza adaptados se deben recomendar en estos pacientes.(AU)

A Wearable Capsule Endoscope Electromagnetic Localization System Based on a Novel WCL Algorithm.

The wearable localization system for wireless capsule endoscopy (WCE) is a potential technology to realize rapid diagnosis and treatment of the gastrointestinal (GI). However, the electromagnetic localization accuracy of WCE still needs to be improved. In this paper, based on RSSI electromagnetic fading model, the accurate fitting parameter values are obtained by Kalman filter and the least square method. A novel weighted centroid localization (WCL) algorithm based on exponential weights is proposed, which can achieve high-accuracy localization by using only sparse reception matrix. The simulation results show that when the standard deviation of the localization data is 7.85, the localization root mean square error (RMSE) is 25.4 mm; when the standard deviation of the localization data is 5.475, the localization RMSE is 2.5 mm. These two localization RMSEs are 38% and 79% less than those of the conventional centroid localization algorithm, respectively. An experimental platform of wearable wireless communication and localization system using 24 array receiving antennas is developed in human phantom environment. The experimental results show that the wearable WCE electromagnetic localization system based on the proposed algorithm achieves a localization RMSE of 36.3 mm, which is 17% lower than that of the conventional centroid localization algorithm and meets the needs of clinical diagnosis.

A method for evaluating sensitivity of electromagnetic localization systems for wireless capsule endoscopes.

This paper studies the use of electromagnetic induction in localization of wireless capsule endoscopes (WECs). There is still currently a need for an accurate localization system to enable localizing possible findings in the gastrointestinal tract, and to develop an active steering system for the capsule. Developing an optimal localization system requires the sensitivity of the system to be analyzed. In this paper, three different coil geometries are modelled with a computer simulation platform, and their sensitivities and target responses are compared. In order to do that, a formulation for the sensitivity based on the dipole model approximation is presented. The first coil array is based on literature and is used as a reference. The second array presents how having more transmit-receive channels in the array effects the sensitivity. The third coil array simulates the effect of increasing the field excitation intensity in different directions by using a three-axial Helmholtz array. In addition, both proposed coil arrays utilize larger coils than the reference. As a result, it seems that both increasing the coil size and the number of field projections interrogating the target increase the overall sensitivity in the region of interest and the target response. The findings suggest that an optimal coil array could utilize both large coils and multiple transmit-receive channels to increase the number of independent fields incident onto the target.

In vivo animal study of the magnetic navigation system for capsule endoscope manipulation within the esophagus, stomach, and colorectum.

BACKGROUND/PURPOSES: Magnetic navigation capsule endoscopy (MNCE) is considered to be an important means to realize the controllable and precise examination of capsule endoscopy (CE) in the unstructured gastrointestinal (GI) tract. For the current magnetic navigation system (MNS), due to the limitation of workspace, driving force, and control method of the CE, only clinical application in the stomach has been realized, whereas the examination of other parts of the GI tract is still in the experimental stage. More preclinical studies are needed to achieve the multisite examination of the GI tract. METHODS: Based on the MNS (Supiee) developed in the laboratory, an X-ray imaging system with magnetic shielding and a commercial CE are integrated to form the MNCE system. Then, in vivo GI tract experiments with a porcine model are performed to verify the clinical feasibility and safety of this system. Moreover, the effects of different control modes on the efficiency and effect of GI tract examination are studied. RESULTS: Animal experiments demonstrate that with the MNCE system, it is convenient to achieve steering control in any direction and multiple reciprocating movements of CE in the GI tract. Benefiting from the flexibility of the three basic control modes, the achieved swing movement pattern of CE can effectively reduce the inspection time. It is demonstrated that the esophageal examination time can be reduced from 13.2 to 9.2 min with a maximum movement speed of 5 mm/s. CONCLUSION: In this paper, the feasibility, safety, and efficacy of the MNCE system for a one-stop examination of the in vivo GI tract (esophagus, stomach, and colorectum) is first demonstrated. In addition, complex movement patterns of CE such as the swinging are proved to effectively improve examination efficiency and disease detection rates. This study is crucial for the clinical application of the MNCE system.