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Capsule Endoscopy
Jonathan Hernandez
| Robert Tisma
2
Outline•
History
•
Anatomy of GI Tract•
Types of Diseases
•
Types of Endoscopic capsules•
Technology
•
Procedure•
Future Developments
3
What Is An Endoscopic Capsule?•
Looks like a pill, but is designed for imaging
•
Takes pictures of the GI (Gastrointestinal) Tract using a built‐in small camera
•
Small enough to complete a trip in the GI Tract
•
Used to detect diseases that the traditional endoscope cannot
•
Main purpose is to investigate the small intestine, since traditional endoscopy does not allow
4
What Is An Endoscopic Capsule?
5
History•
1806 –
Phillip Bozzini
developed first endoscope but was disapproved
•
1908 –
Charles David was the first to use small electric light bulbs
•
1950s –
Harold Hopkins developed “fibroscope”
(fiber optic), which was used both medically and industrially
•
1990 – groups of researchers studied the possible uses of miniature video cameras and wireless transmitters for
wireless endoscopic capsules
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History (Contd.)•
1994 – first patent application was filed for an imaging device with good quality pictures and low power
requirements
•
1999 – first human volunteer was studied after years of animal testing
−
researcher, C. Paul Swain, MD, swallowed the first endoscopic capsule
•
2001 – FDA approved for small bowel examinations in adults and 2003 for children
•
2004 – FDA approved for visualization of esophagus
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Gastrointestinal Tract•
Layers of the GI Tract (GIT)
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Gastrointestinal Tract (Contd.)•
Mucosa−
The inner lining of the GIT−
Epithelium layer:•
Is in direct contact with the contents of the GIT•
In the mouth, pharynx (back of throat), esophagus and anal canal, serves as protective layer
•
In the stomach and intestines, allows for secretion and absorption
−
Lamina Propria:•
Connective tissue, with many blood and lymphatic vessels
•
Lymphatic vessels carry nutrients absorbed from GIT•
Contains cells of the mucosa‐associated lymphatic tissue (MALT)
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Gastrointestinal Tract (Contd.)−
Lamina Propria
(Contd.):•
Cells from MALT protect against disease (small intestine, appendix and large intestine)
−
Muscularis
Mucosae:•
Thin layer of smooth muscle fibers•
Responsible for the many folds of stomach and small intestine
•
Movement ensures that absorbing cells are completely exposed to GIT contents
•
Submucosa−
Areolar
connective tissue, that binds the mucosa and the muscularis
together
−
Contains blood and lymphatic vessels, neurons, glands and lymphatic tissue
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Gastrointestinal Tract (Contd.)•
Muscularis−
In mouth, pharynx, superior and middles parts of esophagus, contain skeletal muscle
−
Every where else, it is smooth muscle−
Inner wall is circular muscle, which is used to constrict−
Outer wall is longitudinal muscle, which is used to contract along the length of the tubing
−
Helps in break down food, mixing it, and propelling it
•
Serosa−
Secretes lubricating fluid
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Gastrointestinal Tract (Contd.)•
Esophagus−
Pushes bolus (swallowed matter) down
−
Lubricates mucosa epithelium for smooth passage of bolus
−
Upper Esophageal Sphincter (skeletal muscle), controls food coming from pharynx
−
Lower Esophageal Sphincter (smooth muscle), controls food entering stomach
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Gastrointestinal Tract (Contd.)
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Gastrointestinal Tract (Contd.)•
Stomach−
Cardia
of stomach connects to esophagus
−
Pylorus connects to duodenum of small intestine
−
Pyloric sphincter (smooth muscle), controls food going to small intestine
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Gastrointestinal Tract (Contd.)
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Gastrointestinal Tract (Contd.)
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Gastrointestinal Tract (Contd.)
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Gastrointestinal Tract (Contd.)•
Small Intestine−
Main purpose is to absorb nutrients
−
Duodenum ‐
25cm
−
Jejunum ‐
100cm
−
Ilium ‐
200cm
−
Ilium joins with large intestine at the ileocecal sphincter (smooth muscle)
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Gastrointestinal Tract (Contd.)
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Gastrointestinal Tract (Contd.)•
Large Intestine−
Main purpose is to absorb water and salts
−
1500cm long, 6.5cm wide
−
Cecum
is connected to the ileocecal
sphincter
−
Cecum
is connected to the colon
−
Colon is divided into four parts: ascending, transverse, descending and sigmoid colon
−
Rectum is the last of the GIT
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Gastrointestinal Tract (Contd.)
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Gastrointestinal Tract (Contd.)
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Some GIT Diseases•
Crohn’s
Disease−
Subclass of diseases from Inflammatory Bowel Disease−
Causes inflammation of the GIT−
Swelling causes pain and leads to emptying of small intestine (e.g
diarrhea)
−
One of the symptoms are rectal bleeding•
Diverticulosis−
Occurs when bulging pouches form at the weak points of the colon walls
−
Can cause intestinal bleeding or inflammation•
Intestinal Polyps−
Abnormal growths in GIT, most often in large intestine−
Thought to be as precursor of colon cancer
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Some GIT Diseases (Contd.)•
Colon Cancer−
Cancerous growths in colon, rectum and appendix
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Some GIT Diseases (Contd.)
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PillCam SB, Given Imaging
•
1st
capsule in the world, developed in 2001•
Imaging and light source on one end of pill•
11mm in diameter, 26mm in length•
Weighs less than 4g•
CMOS image sensor, 256x256 resolution•
Internal battery lasting eight hours•
2 images per second
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MiroCam, IntroMedic•
Developed in 2003•
11mm in diameter, 24mm in length•
CMOS image sensor, 320x320 res. Images•
Internal battery lasting 11 hours•
Software suggests possible sites for bleeding
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PillCam ESO, GivenImaging
•
Developed in 2004•
Two cameras; opposite ends of pill•
Similar weight and dimensions as PillCam
SB•
18 images per second•
Specifically intended for the esophagus•
Patient raised by 30‐degree angles every two minutes until sitting upright
•
20min procedure
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EndoCapsule, Olympus•
Developed in 2004•
Camera surrounded by 6 LEDs•
11mm in diameter, 26mm in length•
CCD image sensor, 320x320 res. images•
Internal battery lasting eight hours•
Allows real time viewing from a proprietary recorder
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Sayaka, RF System•
Developed in 2005
•
One camera that rotates about its center
•
CCD image sensor−
2mega pixel resolution images, allowing 75x magnification
•
Stepping rotation consisting of two shells−
Inner shell spins; takes pictures
•
Wirelessly powered
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Structures (Pillcam ESO)
1. Optical Dome
5. CMOS Image Sensor2. Lens Holder 6. Battery3. Illuminating LEDs
7. ASIC Transmitter
4. Lens
8. Antenna
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Structures (Sayaka)
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Power•
Internal batteries would increase size of pill
•
Can also result in battery leakage, causing health concerns
•
Alternative approach to power the capsule is done outside the body (extracorporeal)
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Power (Contd.)•
Powered through electromagnetic induction
•
Patient wears a vest to transmit power−
Electric current runs through the sending coils in the vest, inducing a current through the receiving coils in the pill
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Image Sensors•
Features the two main types of imaging sensors used in digital cameras
•
CCD (Charge–Coupled Device)−
Generally more sensitive, allowing better images in dim lighting scenarios
−
Better image quality at cost of system size
•
CMOS (Complementary Metal Oxide Semiconductor)−
Generally cheaper to manufacture and does not consume as much power (can be important for internal batteries)
−
Better integrated circuit at cost of image quality
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Image Sensors•
CCD−
Measures light with light sensitive diodes called photosites
−
CCD is 1cm panel of 300,000 to 500,000 photosites
−
Each photosite
measures amount of photons, and converts information to electrons (electric charge)
−
To create colour
images, it measures the intensity of 3 levels of colour: Blue, Green and Red
−
Uses Bayer Filter: there is a percentage of photocites
to measure each colour
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Image Sensors (Contd.)
37
Image Sensors (Contd.)•
CCD −
Computer interpolates data received from nearby area, to find true colour
of light being detected
−
A second layer behind the image sensor, receives photosite
charges
−
Information from second layer, sent to ADC, where a digital data is formed
−
As photosite
charges are passed to second layer, first layer resets for new image
−
Information is then stored on memory device
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Image Sensors (Contd.)•
CMOS−
After sensor receives light input, electric charge is amplified and conducted to other components
−
Essentially it is a transistor, hence no ADC is needed, since the signal is either 1 or 0
−
Binary data stored and new picture is taken
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Image Sensors (Contd.)•
CCD vs. CMOSCCD CMOS
‐high quality sensors‐low noise images
‐more susceptible to noise‐not as good quality
‐higher quality pixels and more of them
‐large in size
‐light sensitivity is lower‐photons hit transistors
instead of photodiodes‐consumes 100 times more
power than CMOS sensor‐consume little power
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Imaging (Contd.)•
Images transmitted wirelessly to the vest worn by patient
−
Stored on a propriety device or an SD card
•
Different approaches to viewing the images−
Real‐time pictures or video−
Flat map by piecing images together like a mosaic−
Images put into video format
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Procedure•
Nothing to eat or drink (including medication) for six hours before going
•
Wear a vest/belt that records the images and in some cases, powers the capsule
•
Capsule swallowed with a glass of water while lying down
•
After two hours, can drink fluids•
Can begin to eat light meals after four hours•
Return after eight to nine hours to have the images transferred to a computer
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Possible Concerns•
Does not interfere with pacemakers but can have recording disrupted
•
Can go about daily activities or to work if needed
•
Camera is disposable; does not need to be returned
•
Advised to stay away from large transmission towers, as well as airports and shopping centers since it may
trigger security screening equipment
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•
Some cameras only record for a set duration −
If stuck, becomes impossible to know whether it has left the body or not
•
Can get stuck in a narrowing; retained within the stomach
−
Occurs in 1% of all patients−
Can help identify possible areas of concern
•
If not out of the body within a day, X‐rays used to verify •
No significant short term causes if retained•
Open surgery may be required for removal
Possible Concerns (Contd.)
44
Future Developments•
iPill
(Intelligent Pill), Phillips−
Wirelessly powered−
Determines position within the stomach−
Measures acidity and temperature−
Drug storage that detects when and if drugs should be released into the body
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•
Body Fluid Sampling−
Negatively pressurized space fitted with a valve−
Allows free collection of fluids for later diagnosis and analysis
•
Drug Delivery System−
Drug storage fitted with a valve within the capsule that can be controlled externally
−
Allows delivery of drugs when needed
Future Developments (Contd.)
46
•
Magnetic Guidance−
Uses external magnetic field generator to freely control the capsule’s movements and direction of observation
•
Ultrasound−
High resolution ultrasoundwith less attenuation
•
Self‐propelled capsule
Future Developments (Contd.)
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The End
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References•
http://www.pillcam.com/Pages/homepage.aspx•
http://www.olympus‐europa.com/endoscopy/2001_5491.htm•
http://www.olympus‐global.com/en/news/2004b/nr041130capsle.cfm•
http://www.rfamerica.com/sayaka/index.html•
http://intromedic.com/en/product/productInfo.asp•
http://intromedic.com/en/product/product_01.asp•
http://medgadget.com/archives/2005/05/capsule_endosco.html•
https://publications.european‐patent‐
office.org/PublicationServer/getpdf.jsp?cc=EP&pn=1618827&ki=A1
•
http://medgadget.com/archives/2005/10/olympus_launche.html•
http://www.dalsa.com/markets/ccd_vs_cmos.asp•
http://www.three‐fives.com/latest_features/feature_articles/250205medical.html•
http://microsystem.re.kr/main_eng/menu04/sub_menu01.asp•
http://www.yomiuri.co.jp/dy/features/0009/080101_06.htm•
http://www.mayoclinic.org/crohns/capsuleendo.html•
http://www.popsci.com/how‐it‐works/article/2008‐03/how‐it‐works‐endoscope‐
camera‐pill
•
http://www.addenbrookes.org.uk/resources/pdf/patient_visitors/patient_information
_leaflets/gastroenterology/PIN1123_retained_capsule.pdf
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References•
http://news.cnet.com/8301‐17938_105‐10095371‐
1.html?part=rss&tag=feed&subj=Crave
•
http://en.wikipedia.org/wiki/Capsule_endoscopy•
http://goliath.ecnext.com/coms2/gi_0199‐5147901/Capsule‐endoscopy‐new‐
applications.html#abstract
•
http://en.wikipedia.org/wiki/Endoscopy•
http://en.wikipedia.org/wiki/Serosa•
http://www.allina.com/CCS/doc/Encyclopedia/2/8871.htm•
http://www.nlm.nih.gov/MEDLINEPLUS/ency/imagepages/19223.htm•
http://www.wrongdiagnosis.com/organ/large_intestine.htm•
http://digestive.niddk.nih.gov/ddiseases/pubs/crohns/•
http://www.healthsquare.com/fgpd/fg4ch05p3.htm•
http://electronics.howstuffworks.com/camcorder2.htm•
http://electronics.howstuffworks.com/digital‐camera1.htm•
http://www.gesa.org.au/leaflets/capsule_endoscopy.cfm•
http://www.addenbrookes.org.uk/resources/pdf/patient_visitors/patient_information
_leaflets/gastroenterology/PIN1122_video_capsule_endoscopy.pdf
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References•
Tortora
G. J., Derrickson
B. Principles of Anatomy and Physiology 12th Edition. John
Wiley & Sons. 2009. U.S.
•
http://www.nlm.nih.gov/MEDLINEPLUS/ency/imagepages/19220.htm•
http://en.wikipedia.org/wiki/Colon_cancer