Abstract and Introduction
Video capsule endoscopy (VCE) is being increasingly used to investigate small bowel pathology. It is the gold standard for obscure gastrointestinal bleeding and iron deficiency anemia. VCE has been in use since 2001 and indications for its use are expanding. VCE is also a useful diagnostic tool in small bowel Crohn's disease, celiac disease, surveillance of polyps, small bowel malignancy and drug-induced small bowel injury. Although VCE is considered a safe and easy procedure, there are a few limitations. These include cost, capsule retention and inability to take a biopsy and perform any therapeutic maneuvers. Contraindications for VCE include pregnancy, patients with a swallowing disorder, history of previous abdominal surgery or concurrent abdomino–pelvic irradiation. This is an overview of VCE, its role and indications in clinical practice, potential complications and contraindications, as well as the ongoing and expected advances in the field.
Video capsule endoscopy (VCE) is a procedure for inspecting the gastrointestinal (GI) tract that is principally used for areas that cannot be visualized by esophago–gastroduodenoscopy and colonoscopy.
Capsule endoscopy (CE) is composed of many parts, such as the ingestible video capsule, the camera (recording device), the source of light (white LED), the complementary metal oxide semi-conductor, the antenna, batteries that run for 8 h and a transmitter with an application-specific integrated circuit. The size of the capsule used for the small intestine is about the size of a large pill (26 × 11 mm), and it weighs about 3.4 g. The viewing field of the CE is about 140°.
The aim of using a video capsule is to take as many images as possible along the GI tract; for example, the capsule for the small intestine can take two images per second, which can produce about 55,000 images during the test.
The idea of CE was developed 30 years ago by two different groups of researchers who worked on it separately; one being a group supervised by the Israeli electro-optical engineer Gavriel Iddan, and the other group being in London, working at the Royal London Hospital (UK) under the original direction of Paul Swain. Both groups shared the aim of discovering a new method to examine the small bowel, particularly areas that could not be seen by ordinary endoscopy.
There are different types of CE on the market according to the manufacturer. The first capsule, produced by Given Imaging (M2A Given Imaging, Yokneam, Israel) in the late 1990s, is called Pillcam™. Since 2008, the second generation of the Pillcam capsule, called Pillcam SB2, has become available, with a wider viewing angle of 156°. Another type of CE developed by Olympus® (Tokyo, Japan), called Olympus EndoCapsule, is different in weight, being 3.8 g rather than 3.4 g, and has a wide viewing angle of approximately 145°. Both the PillCam and the EndoCapsule can take two images per second. In addition, there is another type of video capsule, called MiroCam®, made by IntroMedic (Seoul, Korea). The MiroCam is different from the PillCam and EndoCapsule in that it uses a different technique of data transmission, namely human body communication. The human body is used as conductive media for data transmission and, because of this, the battery may last longer than in the PillCam and EndoCapsule. MiroCam is also different from the previous two capsules in size (24 × 11 mm), it can take three images per second that are a higher resolution in comparison to PillCam. The other type of CE called the OMOM capsule endoscope, which is produced by the Jinshan Science and Technology Group (Chongqing, China). The size of this capsule is 13 × 27.9 mm and weighs <6 g. The OMOM capsule has a viewing angle of 140° and can take two frames per second. The last and most recent model of VCE is the CapsoVision® model (CapsoVision, CA, USA). It stores all images on a microchip and is supposed to offer 360° panoramic view with wire-free technology.
Expert Rev Gastroenterol Hepatol. 2013;7(4):323-329. © 2013 Expert Reviews Ltd.