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Biologically Inspired Robotics
11.1 Introduction
The gastrointestinal (GI) tract is a 30-foot-long structure composed of a
pharynx, esophagus, stomach, small intestine, large intestine, and rectum.
Diseases of the GI tract, such as stomach and intestinal cancer, pose a great
threat to human’s health. According to a publication in Hong Kong (Hospital
Authority of Hong Kong 2006), GI tract–related cancers of the colon, stomach, and rectum are ranked as the third, fourth, and fifth causes of cancer
deaths, respectively, accounting for 18% of the total cancer deaths in Hong
Kong in 2003. Gastroscopy and colonoscopy are the most commonly used
approaches for diagnosis of GI diseases. Although they can provide good
images that reveal the status of the GI tract, neither can reach the small intestine. Moreover, these techniques require sedating the patient, are uncomfortable, and may include a risk of perforation. Furthermore, these operations
require that doctors be very skillful, concentrated, and experienced to navigate the endoscope because the GI tract is very flexible. In 2000, a new kind
of GI endoscopy, that is, capsule endoscopy (CE), was developed. This new
endoscopy technology, developed by Given Imaging Corporation in Israel,
has revolutionized the diagnosis methodology for the digestive tract because
this small device can directly view the entire small intestine without pain,
sedation, or air insufflation, which is a significant breakthrough.
As demonstrated in Figures 11.1 and 11.2, a CE, measuring 26 mm × 11
mm, is a pill-shaped device that consists of a short-focal-length complementary metal oxide semiconductor (CMOS) camera, light source, battery, and
radio transmitter. A patient must fast for about 12 hours before ingesting
the CE. After ingestion, this small device starts to work with the peristalsis
of mucosa of the GI tract and takes images while moving forward along the
digestive tract. Images recorded by the miniature camera are sent out wirelessly to a special recorder attached to the waist. Such a process continues
for about 8 hours until CE battery life ends. Finally, all of the image data in
the recorder are downloaded into a personal computer or a computer workstation, and physicians can view the images and analyze potential sources
of different diseases in the GI tract with the help of specific software. The
diagnosis process is time consuming due to the large amount of video, so
the diagnosis is not a real-time process, paving a potential way for off-line
postprocessing and computer-aided diagnosis. CE was approved by the U.S.
Food and Drug Administration (FDA) in 2001, and it has been reported that
this novel technology has provided great value in evaluating GI bleeding,
Crohn’s disease, ulcers, and other diseases of the digestive tract (Adeler and
Gostout 2003). Moreover, over 800,000 patients have been diagnosed using
CE technology (Given Imaging Ltd. 2009).
One major issue associated with CE is that it takes a long time for physicians to evaluate the large number of images produced. There are about
50,000 images per examination for one patient, and it costs an experienced
Biologically Inspired Robotics
11.1 Introduction
The gastrointestinal (GI) tract is a 30-foot-long structure composed of a
pharynx, esophagus, stomach, small intestine, large intestine, and rectum.
Diseases of the GI tract, such as stomach and intestinal cancer, pose a great
threat to human’s health. According to a publication in Hong Kong (Hospital
Authority of Hong Kong 2006), GI tract–related cancers of the colon, stomach, and rectum are ranked as the third, fourth, and fifth causes of cancer
deaths, respectively, accounting for 18% of the total cancer deaths in Hong
Kong in 2003. Gastroscopy and colonoscopy are the most commonly used
approaches for diagnosis of GI diseases. Although they can provide good
images that reveal the status of the GI tract, neither can reach the small intestine. Moreover, these techniques require sedating the patient, are uncomfortable, and may include a risk of perforation. Furthermore, these operations
require that doctors be very skillful, concentrated, and experienced to navigate the endoscope because the GI tract is very flexible. In 2000, a new kind
of GI endoscopy, that is, capsule endoscopy (CE), was developed. This new
endoscopy technology, developed by Given Imaging Corporation in Israel,
has revolutionized the diagnosis methodology for the digestive tract because
this small device can directly view the entire small intestine without pain,
sedation, or air insufflation, which is a significant breakthrough.
As demonstrated in Figures 11.1 and 11.2, a CE, measuring 26 mm × 11
mm, is a pill-shaped device that consists of a short-focal-length complementary metal oxide semiconductor (CMOS) camera, light source, battery, and
radio transmitter. A patient must fast for about 12 hours before ingesting
the CE. After ingestion, this small device starts to work with the peristalsis
of mucosa of the GI tract and takes images while moving forward along the
digestive tract. Images recorded by the miniature camera are sent out wirelessly to a special recorder attached to the waist. Such a process continues
for about 8 hours until CE battery life ends. Finally, all of the image data in
the recorder are downloaded into a personal computer or a computer workstation, and physicians can view the images and analyze potential sources
of different diseases in the GI tract with the help of specific software. The
diagnosis process is time consuming due to the large amount of video, so
the diagnosis is not a real-time process, paving a potential way for off-line
postprocessing and computer-aided diagnosis. CE was approved by the U.S.
Food and Drug Administration (FDA) in 2001, and it has been reported that
this novel technology has provided great value in evaluating GI bleeding,
Crohn’s disease, ulcers, and other diseases of the digestive tract (Adeler and
Gostout 2003). Moreover, over 800,000 patients have been diagnosed using
CE technology (Given Imaging Ltd. 2009).
One major issue associated with CE is that it takes a long time for physicians to evaluate the large number of images produced. There are about
50,000 images per examination for one patient, and it costs an experienced