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Anatomy of the GI tract
Diseases
Conventional Endoscopy
Capsule Endoscopy
Current Technology
Future Concepts/Developements
The G.I. Tract7.5 meters long
Upper GI tract
Mouth -> esophagus
Lower GI Tract
Bowel (Intestine)
Small intestines
Large Intestines
Diseases of the GI Tract
Ulcers
Drug/food induced inflammations (NSAID)
Bleeding
Tumors
Cancers
Parasites
What is EndoscopyAll these diseases are very visible, but they’re on the inside of your body
Most GI diseases affect the Mucosa layer which comes in direct contact with the food (or bolus).
Easily diagnosed if doctors can See it.
Endoscopy allows doctors to visualize the GI tract
Two ways to look inside:
Exploratory Surgery
Endoscopy
Small Intestines
Duodenum (20cm)
Jejunum (100-210cm)
Illeum (150-160cm)
1/3 the diameter of the Large intestines
4-5x the length of the Large intestines
Capsule Endoscopy
• Small intestine is • Too convoluted• Too long
• Capsule endoscopy is wireless• Can see the entire length of small
intestine
Brief History
• Started by Gavriel Iddan• Formerly an Israeli scientist working
on guided missile technology• Inspired by his friend who suffers
from chronic abdominal pain
PillCam (May 2001)
• Camera at the tip of the capsule• Strobe LEDs sync-ed with picture taking• 2 frames per second• CMOS sensor (190,000 - 210,000 pixels)• Battery powered• 26 x 11mm• US$450 each
Norika3 (December 2001)
• Camera at the tip of the capsule (slightly angled downwards for better exposure)
• Focus adjustment
• Wireless power transmission
• Posture control
• Simulated 3D images by LED manipulation
• 30 frames per second
• CCD Sensor (410,000 pixels)
• 23 x 9mm
• US$100
Sayaka (Dec 2005)
• Camera on the side of the capsule
• Twin layered capsule (camera rotation)
• ‘Stepping rotation’ using electromagnets
• Creates a flat map of the entire GI tract
• 30 frames per second (870,000 pictures over 8 hour)
• CCD Sensor (410,000 pixels)
• Focus adjustment
• 2MB/mm2
• 75x magnification on 17” display
• Wireless power transmission
MiRO
• In development• 320 x 320 pixel resolution• f/sec 1.4-2.8 (focusing capabilities)• Localization (Reverse Telemetry)• Real time image acquisition
• Displays to a PC/PDA• 11 x 24mm• Battery powered
Pros
• Non-invasive• Can access the entire small intestine• No need for exploratory surgery• Cheap• Time-efficient
Cons
• Lack of control• Pill can get stuck• Cannot further examine areas of
interest• Camera view might be obscured by
bowel contents
Development Challenges
• How to create a device small enough, and comfortable enough to swallow while packing sophisticated electronics.
• The microelectronics must be able to take high resolution pictures, transmit the data back, and operate for at least 6-8 hours.
• How to give user more control over the capsule’s movement and camera direction
Size
• Size reduction means removing unnecessary components
• Batteries are typically large and carries limited amount of power
• Micro-devices:• Biopsy tools• Drug sprayers• Laser or Cautery devices (+power supply)
Power
• Batteries typically do not carry enough power to last the desired amount of operation time.
• Batteries can be toxic if leaked into the digestive system
• Solution: Remove the battery• Wireless power transmission offers the possibility
of unlimited operation time, size reduction, and no risk of toxin contamination
Block DiagramWireless power transmission
Splitting the DSP from the imaging CCD circuit allows for 94% of the power consumption to be handled externally
Image Resolution
• Images taken must be clear, sharp, and have good colour definition
• CCD vs. CMOS• Focus adjustment• Simulated 3D (depth perception)
Movement Control
• Norika3 uses Electromagnet induced ‘Posture Control’
• Sayaka uses Electromagnets to produce ‘Stepping Rotations’
• MiRO sends telemetry back to inform user of current position
Future Developments
• Drug delivery• Micro-biopsy• Laser treatments• Additional sensors
• (pH, Temp, pressure sensors)• Cost reduction
Last CommentsCapsule endoscopy marks a leap in the quality of care for patients
Pills for Small intestine visualization are available today
Next step, the Sayaka capsule will allow for visualization of the entire Gi tract
Very painless, low-cost procedure with high degree of accuracy
Future pills can be controlled and will be involved in treatment process and more involved diagnosis techniques
References
• A. Arshak, K.Arshak, D. Morris, E.Jafer, O. Korostynska, G.Lyons, & D. Waldron. A Review of Digestible Microsystems for Gastrointestinal Tract Diagnostic Applications In: Critical Reviews in Biomedical Engineering, 34(2): 163-186 (2006)
• IEEE Standard for Safety levels with Respect to Human Exposure to Radio Frequency, Electromagnetic Fields, 3kHz to 300GHz. In: IEEE Standard c95.1-1991. New York: IEEE; 1999.
• Glukhovsky A, Jacob H. The Development and application of wireless capsule endoscopy. Int J Med Robot Comput Assist Surg. 2004; 1(1):112-23.
• Iddan G, Meron G, Glukhovsky A, Swain P. Wireless Capsule Endoscopy. Nature. 2000; 405-417.
• Norika3. Data Sheet; 2003.
• RF System Adopts Silicon Laboratories’ Small Form Factor Microcontroller for Advanced Medical Application. In: Business Wire. Aug. 09, 2006
• Tortora G. J., Derrickson B. Principles of Anatomy and Physiology 11th Edition. John Wiley & Sons. 2006. U.S.
• http://microsystem.re.kr/main_eng/menu04/sub_menu01.asp
• http://www.rfnorika.com/eng/system/sys_001.html - sys_009.html
• http://www.rfamerica.com/sayaka/index.html
• http://www.givenimaging.com/Cultures/en-US/given/english
• http://www.dalsa.com/markets/ccd_vs_cmos.asp
• http://www.highbeam.com/doc/1G1-108722548.html
References (Cont’d)
• http://www.cbc.ca/health/story/2002/09/04/video_pill020904.html
• http://www.cbc.ca/news/story/2001/08/03/nano_camera010803.html
• http://www.findarticles.com/p/articles/mi_m0EIN/is_2005_August_9/ai_n14875232
• http://www.teachnet.ie/farmnet/images/Digest3.gif
• http://en.wikipedia.org/wiki/Electric_motor
• http://en.wikipedia.org/wiki/Electromagnetic_wave
• http://en.wikipedia.org/wiki/Magnets
• http://en.wikipedia.org/wiki/Small_intestine
• http://en.wikipedia.org/wiki/Large_Intestine
• http://en.wikipedia.org/wiki/Gavriel_Iddan
• http://en.wikipedia.org/wiki/Wireless_capsule_endoscopy
• http://en.wikipedia.org/wiki/Gastrointestinal_tract