Novel imaging enhancements in capsule endoscopy. Gastroenterol Res Pract. 2013;2013:304-723. [PMID: 23878532 PMCID: PMC3710602 DOI: 10.1155/2013/304723]

Application of capsule endoscopy in patients with chronic and recurrent abdominal pain: Abbreviated running title: capsule endoscopy in abdominal pain

OBJECTIVE

The incidence of chronic and recurrent abdominal pain increases every year, while the diagnosis is still unsatisfactory even after a number of check-ups. This study aimed to evaluate the diagnosis value of capsule endoscopy in patients suffering from chronic and recurrent abdominal pain.

METHODS

A retrospective case study was performed in 80 chronic and recurrent abdominal pain patients at Xiangyang Central Hospital from January 2013 to November 2017. Meanwhile, diagnoses by capsule endoscopy were collected for analysis.

RESULTS

Abnormal findings were found in 54 of 80 (67.5%) patients. The findings in chronic and recurrent abdominal pain patients include small intestinal erosion and congestion, small intestinal ulcers, small intestinal parasites, small intestinal vascular malformations, small intestinal polyps, small intestinal diverticulum, and small intestinal lymphangiectasia. There were no immediate significant side effects without being reported up to 1 month after ingestion of the capsule. The capsule was evacuated by all patients.

CONCLUSIONS

Capsule endoscopy has a great value in the diagnosis of chronic and recurrent abdominal pain with satisfactory safety and less pain for patients. Inflammatory lesions and ulcers in the small intestine account for the majority of positive findings in these patients.

Endoscopic capsule robot-based diagnosis, navigation and localization in the gastrointestinal tract

The proliferation of video capsule endoscopy (VCE) would not have been possible without continued technological improvements in imaging and locomotion. Advancements in imaging include both software and hardware improvements but perhaps the greatest software advancement in imaging comes in the form of artificial intelligence (AI). Current research into AI in VCE includes the diagnosis of tumors, gastrointestinal bleeding, Crohn’s disease, and celiac disease. Other advancements have focused on the improvement of both camera technologies and alternative forms of imaging. Comparatively, advancements in locomotion have just started to approach clinical use and include onboard controlled locomotion, which involves miniaturizing a motor to incorporate into the video capsule, and externally controlled locomotion, which involves using an outside power source to maneuver the capsule itself. Advancements in locomotion hold promise to remove one of the major disadvantages of VCE, namely, its inability to obtain targeted diagnoses. Active capsule control could in turn unlock additional diagnostic and therapeutic potential, such as the ability to obtain targeted tissue biopsies or drug delivery. With both advancements in imaging and locomotion has come a corresponding need to be better able to process generated images and localize the capsule’s position within the gastrointestinal tract. Technological advancements in computation performance have led to improvements in image compression and transfer, as well as advancements in sensor detection and alternative methods of capsule localization. Together, these advancements have led to the expansion of VCE across a number of indications, including the evaluation of esophageal and colon pathologies including esophagitis, esophageal varices, Crohn’s disease, and polyps after incomplete colonoscopy. Current research has also suggested a role for VCE in acute gastrointestinal bleeding throughout the gastrointestinal tract, as well as in urgent settings such as the emergency department, and in resource-constrained settings, such as during the COVID-19 pandemic. VCE has solidified its role in the evaluation of small bowel bleeding and earned an important place in the practicing gastroenterologist’s armamentarium. In the next few decades, further improvements in imaging and locomotion promise to open up even more clinical roles for the video capsule as a tool for non-invasive diagnosis of lumenal gastrointestinal pathologies.

What is the effective clinical use of small bowel capsule endoscopy in real life?

Capsule endoscopy is a noninvasive and easy method for evaluating the gastrointestinal tract. Since the wireless capsule endoscopy system was first developed, many new technical improvements have been made in order to gain maximum benefit from the procedure. However, at this stage, it remains a diagnostic modality, the main indication for its use being obscure gastrointestinal bleeding. Capsule endoscopy is only contraindicated in symptomatic intestinal obstruction. New indications for use and therapeutic options may become possible with the further development of nanotechnologies.

Recommendations to quantify villous atrophy in video capsule endoscopy images of celiac disease patients

AIM

To quantify the presence of villous atrophy in endoscopic images for improved automation.

METHODS

There are two main categories of quantitative descriptors helpful to detect villous atrophy: (1) Statistical and (2) Syntactic. Statistical descriptors measure the small intestinal substrate in endoscope-acquired images based on mathematical methods. Texture is the most commonly used statistical descriptor to quantify villous atrophy. Syntactic descriptors comprise a syntax, or set of rules, for analyzing and parsing the substrate into a set of objects with boundaries. The syntax is designed to identify and distinguish three-dimensional structures based on their shape.

RESULTS

The variance texture statistical descriptor is useful to describe the average variability in image gray level representing villous atrophy, but does not determine the range in variability and the spatial relationships between regions. Improved textural descriptors will incorporate these factors, so that areas with variability gradients and regions that are orientation dependent can be distinguished. The protrusion syntactic descriptor is useful to detect three-dimensional architectural components, but is limited to identifying objects of a certain shape. Improvement in this descriptor will require incorporating flexibility to the prototypical template, so that protrusions of any shape can be detected, measured, and distinguished.

CONCLUSION

Improved quantitative descriptors of villous atrophy are being developed, which will be useful in detecting subtle, varying patterns of villous atrophy in the small intestinal mucosa of suspected and known celiac disease patients.

Review: capsule colonoscopy-a concise clinical overview of current status

The colon capsule endoscopy (CCE) was first introduced in 2007. Currently, the main clinical indications for CCE are completion of incomplete colonoscopy, polyp detection and investigation of inflammatory bowel disease (IBD). Although conventional colonoscopy is the gold standard in bowel cancer screening, incomplete colonoscopy remains a problem as lesions are missed. CCE compares favourably to computer tomography colonography (CTC) in adenoma detection and has therefore been proposed as a method for completing colonoscopy. However the data on CCE remains sparse and current evidence does not show its superiority over CTC or conventional colonoscopy in bowel cancer screening. CCE also seems to show good correlation with conventional colonoscopy when used to evaluate IBD, but there are not many published studies at present. Other significant limitations include the need for aggressive bowel preparation and the labour-intensiveness of CCE reading. Therefore, much further software and hardware development is required to enable CCE to fulfill its potential as a minimally-invasive and reliable method of colonoscopy.

Capsule endoscopy: The road ahead

Since its introduction into clinical practice 15 years ago, capsule endoscopy (CE) has become the first-line investigation procedure in some small bowel pathologies, and more recently, dedicated esophageal and colon CE have expanded the fields of application to include the upper and lower gastrointestinal disorders. During this time, CE has become increasingly popular among gastroenterologists, with more than 2 million capsule examinations performed worldwide, and nearly 3000 PubMed-listed studies on its different aspects published. This huge interest in CE may be explained by its non-invasive nature, patient comfort, safety, and access to anatomical regions unattainable via conventional endoscopy. However, CE has several limitations which impede its wider clinical applications, including the lack of therapeutic capabilities, inability to obtain biopsies and control its locomotion. Several research groups are currently working to overcome these limitations, while novel devices able to control capsule movement, obtain high quality images, insufflate the gut lumen, perform chromoendoscopy, biopsy of suspect lesions, or even deliver targeted drugs directly to specific sites are under development. Overlooking current limitations, especially as some of them have already been successfully surmounted, and based on the tremendous progress in technology, it is expected that, by the end of next 15 years, CE able to perform both diagnostic and therapeutic procedures will remain the major form of digestive endoscopy. This review summarizes the literature that prognosticates about the future developments of CE.

Emerging Issues and Future Developments in Capsule Endoscopy

Capsule endoscopy (CE) has transformed from a research venture into a widely used clinical tool and the primary means for diagnosing small bowel pathology. These orally administered capsules traverse passively through the gastrointestinal tract via peristalsis and are used in the esophagus, stomach, small bowel, and colon. The primary focus of CE research in recent years has been enabling active CE manipulation and extension of the technology to therapeutic functionality; thus, widening the scope of the procedure. This review outlines clinical standards of the technology as well as recent advances in CE research. Clinical capsule applications are discussed with respect to each portion of the gastrointestinal tract. Promising research efforts are presented with an emphasis on enabling active capsule locomotion. The presented studies suggest, in particular, that the most viable solution for active capsule manipulation is actuation of a capsule via exterior permanent magnet held by a robot. Developing capsule procedures adhering to current healthcare standards, such as enabling a tool channel or irrigation in a therapeutic device, is a vital phase in the adaptation of CE in the clinical setting.