Dennis Hissink : December 2nd 2004 - 14:18 CET
Olympus Medical develops capsule camera technology
Olympus Medical Systems Corporation has developed key technologies, centered on "Capsule guidance system" and "Wireless power supply system", for capsule endoscopes to be used in all parts of the gastrointestinal tract, including the esophagus, the stomach and the colon. Olympus has always believed it is essential to equip capsule endoscopes with functions that enable them to be freely operated within the gastrointestinal tract without batteries, just like today's gastrointestinal endoscopes. It continues development work on the associated necessary technologies for treatment and diagnosis, as well as observation. Olympus has developed various fiberscopes and videoscopes since it unveiled the first practical gastrocamera in 1950.|
One of the most recent extra-slim video endoscopes feature high-definition observation, another a distal-end outer diameter measuring only 5mm. Olympus has also prepared a range of endotherapy accessories, including devices for arresting bleeding, excising polyps and mucous membrane and recovering foreign bodies with minimum invasiveness. These promote greater efficiency in medical institutions and help improve quality of life for the patients. Gastrointestinal endoscopes are now recognized as the only medical devices that can simultaneously perform observations, diagnoses (tissue extraction), and treatment. As a result, they are now widely used in medical institutions throughout Japan.|
Capsule endoscope technology
(1) Technology of capsule endoscope : Compact, low power-consumption imaging technology, wireless transmission technology
(2) Capsule guidance system : Navigates (capsule) freely within the gastrointestinal tract
(3) Wireless power supply system : Eliminates constraints on operating time and energy levels
(4) Drug delivery system : Administer drugs directly to the affected area
(5) Body fluid sampling technology : Extracts body fluid for diagnosis and analysis
(6) Self-propelled capsule : Propels (capsule) freely within the gastrointestinal tract
(7) Ultrasound capsule : Ultrasound scanning from inside the body
Meanwhile, capsule endoscopes differ from conventional endoscopes in that they do not involve tube insertions. Instead, this examination method is expected to make life easier for patients because the endoscopes take the form of easy-to-swallow capsules that do not require topical anesthesia in the throat. After they have been taken orally, the capsule endoscopes generally available today are carried through the body by the peristaltic movement of the stomach and the intestines. During this process, they automatically take images of the gastrointestinal tract.
Olympus has for many years continued research into bringing the functionality of capsule endoscopes steadily closer to the functionality of conventional endoscopes. The most recently developed technologies are the key to developing the capsule endoscopes of the future. They include technology to control the capsule endoscope so that it can easily be brought closer to the part of the body that needs to be examined, and look at parts that are in shadow. Other technologies eliminate the need for batteries inside the capsule by providing electricity from outside the body, allow drugs to be delivered directly to the target affected area, and allow samples to be collected for diagnosis and analysis.
Descriptions of Individual Technologies
(1) Passive capsule observation endoscopes (Technology of capsule endoscope)
These basic capsule endoscopes are equipped with the basic technologies needed for observation. The capsule is 26mm long with an external diameter of 11mm. It features compact, low power-consumption imaging technology and wireless transmission technology.
With a view to commercializing this type for use in small intestine applications, Olympus initiated clinical trials in the fall of 2004.
Compact, low power-consumption imaging technology (A supersensitive image pickup device illuminates the interior of the body and captures images through an ultra-compact lens.)
Compact, low power-consumption wireless transmission technology (The images captured by the image pickup device are transmitted outside the body by wireless through an ultra-small antenna.)
(2) Capsule guidance system
This technology uses magnetism to freely control the capsule’s movements. Olympus is working on development in a joint effort with the Arai/Ishiyama Laboratory, Research Institute of Electrical Communication, Tohoku University. The principle behind the technology calls for the creation of a uniform magnetic field in any direction (N/S Poles) by an external magnetic field generator using three pairs of opposing electromagnets arranged in three directions X, Y and Z (vertically, laterally and depths). The capsule endoscope can then be turned in any desired direction by means of its built-in magnet. The free directional magnetic field is then used to generate a rotating magnet field which rotates the capsule, generating thrust through the spiral structure on the capsule’s exterior. Since this allows free control of forward and reverse motion and motional direction, the capsule can be made to approach the part of the body to be inspected. The direction of observation can also be adjusted.
(3) Wireless power supply system
This technology provides an extracorporeal supply of the energy required for the capsule's built-in compact image pickup device and image transmission from within the capsule. Coils located outside the body use electromagnetic induction to provide electric power to the receiving coils inside the capsule. This makes it possible to secure the electric energy needed for long-term observations and the instantaneous electric power needed for high frame-rate photography.
(4) Drug delivery system
Inside the capsule there is a deflatable balloon containing drugs fitted with a small valve that can be controlled by communications from outside the body. This allows drugs to be delivered freely at any given time or place.
(5) Body fluid sampling technology
There is also a negatively-pressurized space within the capsule for storing extracted body fluids using a small valve that can be controlled by communications from outside the body. This is useful for diagnosis and analysis because it allows free collection of body fluids.
(6) Self-propelled capsule
The body of the capsule can propel itself freely within the gastrointestinal tract because it is fitted with an a mechanism that serves as a propelling mechanism and requires no external driving apparatus. Olympus is currently working on the development of several types of propelling mechanisms, including a twin-spiral type and a caterpillar-type.
(7) Ultrasound capsule
The ultrasound capsule makes it possible to conduct ultrasound scanning from inside the body because it incorporates the necessary miniaturized functions within itself. Since it radiates ultrasound from inside the body cavities, it is expected to deliver higher-resolution ultrasound images with less attenuation than those obtainable from external ultrasonography.