Transcript Biomedical Medical Engineering

Biomedical Engineering
University of Wisconsin-Madison
Eric Lee, John Harrison, Albert Kwansa,
Jacqueline Wong, Miguel Benson
Definition of BME
•
•
Development and manufacture of prostheses,
medical devices, diagnostic devices, drugs and
other therapies
Combines expertise of engineering with
medical needs for the progress of health care
BME Overview
Biomechanics
•
•
•
Application of mechanical principles to the
study of human body movements
Muscles, bones, tendons, and ligaments
o Anatomy, microstructure
Static and dynamic analyses of force profile
o Stress, strain, coordination, power output
Biomechanics

Example: broken leg
Anatomy
http://academic.wsc.edu/faculty/jatodd1
/351/tibia_fibula.jpg
Microstructure
http://upload.wikimedia.org/wikipedia/com
mons/3/34/Illu_compact_spongy_bone.jpg
Biomechanics

Fracture Schematics

Behave like cement

Good in compression

Poor in tension

Low tolerance for
torsion
Butterfly Cut
Fragment
X-ray



Electromagnetic wave and perform radiation
Radiation pass through patient and some are
being absorbed
Image are created on detector by radiation that
pass through the subject
X-ray Applications

Cardiovascular system

Skeletal system

Soft tissue (e.g. lung)
Ultrasonography



A sound wave is produced.
Sound wave is reflected and
forming echo from layers
between different tissues.
Sound wave is changed to
electrical pulses for image
production.
Ultrasonography
Applications


Muscle and soft tissue
Obstetric sonography
www.medical.philips.com
http://zoot.radiology.wisc.edu/
MRI (Magnetic Resonance Imaging)




Polarize (align spin)
of H2 atoms in body
Disrupt spins at one
“slice” of body
Measure energy
given off as atoms
realign
Detects
concentration of H2
atoms
MRI Application



Soft tissue
imaging
Use of contrast
Combined with
CT info
CT (Computed Tomography)



Scanner looks much like
MRI scanner
Takes many X-rays
around body
Properties much like
X-ray


Image from density of
material
Typically used for
skeletal imaging
CT Application


Form 2-D and 3-D
images from X-rays
Can use contrasts
as well to enhance
image of soft
tissue
Biomaterials


Any foreign material that comes into
contact with a biological system
Diverse area of Biomedical Engineering



Cancer drug delivery
Tissue engineering
Cell implantation
Micro-encapsulation

Challenge: Re-establish testosterone level

Solution: Insert testosterone producing cells
Cell Viability


Cell viability and function must be
preserved long term.
Micro-encapsulation provides a defense
and preserves cell function.
Hydrogel

Cell
Capsule material:
Hydrogel

Chemical composition:
Polyethylene Glycol
HO-(CH2-CH2-O)n-H

Physical characteristics:
Microcapsule Parameters
Microcapsule Size
Size exclusion via mesh size
LH, FSH, O2, Nutrients
Antibodies
Testosterone,
Wastes
Biocompatibility
Degradation
Tissue Engineering (TE)
TE involves the development of
biological substitutes to restore or
replace lost tissue function (Langer and
Vacanti, 1993).
TE Motivation



Divergence between the supply and demand
of organ & tissue replacements.
Current methods  low supply, immune
rejection, and inability to repair and
develop.
Major goals of TE:



Provide living biological replacements
Tissue physiology & pathology
Pharmaceutical testing
TE Approach: Cell Source
Cells + Scaffold
Cells + Scaffold + Bioreactor
Growth Factors + Scaffold
TE Range
Liver,
Pancreas,
Kidney
Nerve
Skin
Muscle
Bone,
Cartilage,
Tendon
TE Examples
Cardiac TE – heart valve, myocardium
Metabolic TE – liver, bladder, pancreas
http://www.chir.unizh.ch/cardio/cardiotext/tissueengineering.html
(Hoerstrup et al. Circulation 2002)
Musculoskeletal TE – bone, cartilage
Neural TE – nerve guidance channel for PNS
Proximal
http://en.wikipedia.org/wiki/Image:Woven_bone_matrix.jpg
Distal
Common Post-graduate Paths
Bachelor’s
Degree
Graduate School
Master’s
Degree
Doctorate
Industry
Academia
Professional Schools
•Medical School
•Dental School
•Law School
•Business School
Combined Programs
Medical & Graduate School
(M.D./Ph.D.)
Questions