2. Role of MEMS and nanotechnology
in medical technologies
.
3. .
First of all, what is MEMS ?
• MEMS stands for Micro Electro Mechanical Systems.
• It is a technique of combining Electrical and Mechanical
components together on a chip, to produce a system of miniature
dimensions ..
• By miniature, we mean dimensions less than the
thickness of human hair !!!!
4. .
Benefits of MEMS and nanotechnology
in medical applications
• Small volume of reagent samples (like blood), required for analysis.
• Low power consumption, hence lasts longer on the same battery.
• Less invasive, hence less painful.
• Integration permits a large number of systems to be built on a single chip.
• Batch processing can lower costs significantly.
• Existing IC technology can be used to make these devices.
• Silicon, used in most MEMS devices, interferes lesser with body tissues.
5. .
Can MEMS devices really replace the
existing medical devices ?
• A lot of MEMS medical
devices have been developed
that are much more sensitive
and robust than their
conventional counterparts.
• Market trends for MEMS
medical devices show a
promising future ahead.
http://www.sensorsmag.com/articles/0497/medical/main.shtml
www.edmond-wheelchair.com/ bp_monitors3.htm
6. .
MEMS and endoscopy
• What is endoscopy ?
• A diagnostic procedure which involves the introduction of a flexible device into
the lower or upper gastrointestinal tract for diagnostic or therapeutic purposes.
• Conventional endoscopes
• Can be used to view only the first
third of the small intestine.
• Require sedation of patient
• Is an uncomfortable procedure
http://www.surgical-optics.com/new_autoclavable_rigid_endoscope.htm
http://www.mobileinstrument.com
7. .
MEMS redefines endoscopy with
“Lab on a Pill”
Size : 35mm
Components of lab on a pill
• Digital camera (CMOS Technology)
• Light source
• Battery
• Radio transmitter
• Sensors (MEMS Technology)
Requires no sedation
Can show a view of the
entire small intestine
Can aid in early detection
of colon cancer
http://www.spie.org/web/oer/august/aug00/cover2.html
10. .
Working of this magic pill !
• The pill is intended to be swallowed like any normal pill.
• Once within the body, the pill's sensors sample body fluids and
pick up "meaningful patient data" such as temperature, dissolved
oxygen levels and pH.
• The pill is expected to retrieve all data over a 12-hour period and
disposed off, once excreted.
• This data is transmitted wirelessly to a card attached
to the wrist of the individual.
11. .
Micro-surgical tools
• Present day surgeons operate within a domain
restricted by the mobility and control of the
surgical tools at hand.
• MEMS surgical tools provide the flexibility and
accuracy to perform precision surgery.
12. .
MEMS driven scalpels
• Precise control of the scalpel is
an important requirement in any
surgery.
• MEMS piezoelectric motor help
to accurately position the scalpel.
• MEMS pressure sensors
incorporated on the scalpel, can
help to measure the force exerted
on the area operated upon.
Accordingly, the scalpel can he
handled.
http://www.ee.ucla.edu/~jjudy/publications/conference/msc_2000_judy.pdf
14. .
Ultrasonic MEMS cutting tool
• These tools make use of piezoelectric materials attached to the cutter.
• Consist of microchannels to flush out the fluid and debris while
cutting.
• Can be used to cut tough tissues, like the hardened lenses of
patients with cataract
http://www.ee.ucla.edu/~jjudy/publications/conference/msc_2000_judy.pdf
16. .
Skin Resurfacing
• Skin resurfacing is a form of cosmetic surgery that is often
used to aesthetically enhance the appearance of wrinkles, skin
lesions, pigmentation irregularities, moles, roughness, and scars.
Conventional resurfacing techniques involve the use of :
• Dermabraders – devices or tools used in plastic surgery.
• Chemical peels – chemicals such as glycolic acid.
17. .
MEMS skin resurfacing tools
• Though still not commercially available, MEMS tools have been found to
overcome many drawbacks present in the conventional techniques.
• They can be used to remove raised skin lesions as well as lesions upto certain
depths.
• These MEMS structures are packaged
onto rotary elements and used
over the affected areas.
• The debris can then be sucked out
using a suction pump.
http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=12787986&dopt=Abstract
18. .
Micro/Nano Robots in medical field
• These are micro/nano scale devices capable of treating and
eliminating medical problems.
• Such problems may arise due to the accumulation of unwanted
organic substances, which interfere with the normal body
functions, such as :
– Tumors
– Life threatening blood clots
– Accumulation of scar tissue
– Arterial blockage
– Localized sites of infection.
20. .
MEMS microneedles
• MEMS enables hundreds of hollow
microneedles to be fabricated on a single
patch of area, say a square centimeter.
• This patch is applied to the skin and
drug is delivered to the body using
micropumps.
• These micropumps can be electronically
controlled to allow specific amounts of
the drug and also deliver them at
specific intervals.
• Microneedles are too small to reach and
stimulate the nerve endings, and hence
cause no pain to the body.
gtresearchnews.gatech.edu/ newsrelease/NEEDLES.htm
http://www.pharmtech.com/pharmtech/data/articlestandard/pharmtech/022004/80733/article.pdf
21. .
Smart Pill
• A MEMS device that can be implanted
in the human body.
• Consists of
– biosensors
– Battery
– Control circuitry
– Drug reservoirs
• The biosensors sense the substance to be
measured, say insulin.
• Once this quantity falls below a certain
amount required by the body, the pill
releases the drug.
http://mmadou.eng.uci.edu/
22. .
Challenges for MEMS medical sensors
• Biocompatibility remains the biggest hurdle for
MEMS medical devices.
• Life of the device.
• Retrieving data out of the device.
• Resist drifting along with the body fluids.
