Download Medical Imaging for Solving The Mummy`s Mystery And More…

Medical Imaging for
Solving The Mummy’s Mystery
And More…
Professor Aly A. Farag
Computer Vision and Image Processing Laboratory
University of Louisville
Louisville, Kentucky, USA
E-mail: [email protected]
www.cvip.uofl.edu
The Computer Vision and Image
Processing Laboratory (CVIP Lab)
The CVIP Lab. was established in 1994 at the University of Louisville.
Has two broad focus areas: computer vision and medical imaging.
Hosts unique and modern hardware for imaging, computing and
visualization.
CVIP Facilities
2 Supercomputers
Robotic
Arm
Card-Eye
ImmersaDesk
2 Robotic
Platforms
3D Scanner
Panoramic Displays
CVIP People…
Egyptology 101
•
•
•
•
•
Pyramids
Heliographic
Conquerors of Egypt
Mummification
Great VISIOTRS of Egypt (e.g.,
Prophets)
• Etc…
Mummification Story
• The process of
mummification has
two stages.
• First, the
embalming of the
body.
• Then, the wrapping
and burial of the
body.
Embalming the body
1
First, his body is taken to the tent known
as 'ibu' or the 'place of purification'. There
the embalmers wash his body with goodsmelling palm wine and rinse it with water
from the Nile.
www.ancientegypt.co.uk/mummies
The British Museum
2
One of the embalmer's men makes a
cut in the left side of the body and
removes many of the internal organs.
It is important to remove these
because they are the first part of the
body to decompose.
Embalming the body
3
4
A long hook is used to smash
the brain and pull it out
through the nose.
The liver, lungs, stomach and intestines are
washed and packed in natron which will dry
them out. The heart is not taken out of the
body because it is the centre of intelligence
and feeling and the man will need it in the
afterlife.
5
The body is now covered and stuffed with
natron which will dry it out. All of the fluids,
and rags from the embalming process will be
saved and buried along with the body.
www.ancientegypt.co.uk/mummies
The British Museum
Embalming
the
body
After forty days the body is washed
again with water from the Nile. Then it
is covered with oils to help the skin stay
elastic.
6
7
Finally the body is covered again with
good-smelling oils. It is now ready to be
wrapped in linen.
www.ancientegypt.co.uk/mummies
The British Museum
The dehydrated internal organs are
wrapped in linen and returned to the body.
The body is stuffed with dry materials such
as sawdust, leaves and linen so that it looks
lifelike.
8
1
Wrapping the mummy
First the head and
neck are wrapped
with strips of fine
linen. Then the
fingers and the toes
are individually
wrapped.
This is the
'Isis knot'
amulet which
will protect
the body.
www.ancientegypt.co.uk/mummies
The British Museum
2
The arms and legs
are wrapped
separately. Between
the layers of
wrapping, the
embalmers place
amulets to protect
the body in its
journey through the
underworld.
This is the 'Plummet'
amulet which will keep
the person balanced in
the next life.
Wrapping the mummy
A priest reads spells
out loud while the
mummy is being
wrapped. These
spells will help
ward off evil spirits
and help the
deceased make the
journey to the
afterlife
5
More linen strips are
wrapped around the
body. At every layer,
the bandages are
painted with liquid
resin that helps to
glue the bandages
together.
3
4
The arms and legs
are tied together. A
papyrus scroll with
spells from the
Book of the Dead is
placed between the
wrapped hands.
www.ancientegypt.co.uk/mummies
The British Museum
Wrapping the mummy
6
A cloth is wrapped around the
body and a picture of the god
Osiris is painted on its surface.
7
www.ancientegypt.co.uk/mummies
The British Museum
Finally, a large cloth is wrapped
around the entire mummy. It is
attached with strips of linen that
run from the top to the bottom of
the mummy, and around its
middle. A board of painted wood
is placed on top of the mummy
before the mummy is lowered into
its coffin. The first coffin is then
put inside a second coffin
Tchaenhotep
•
Ta= 'the', and hotep= 'content or calm'.
•
The overall name may be translated as 'the one who is
content'.
Tchaenhotep’s History
• The tombs were first discovered
in 1903, over one hundred
years ago.
• The mummy and the sarcophagus
came to the United States to be
displayed at the 1904 St. Louis
World’s Fair in the “Streets of Cairo
Exhibit”.
Tchaenhotep’s History
• Louisvillian Samual Thruston
Ballard was later responsible
for bringing the mummy to
Louisville where the mummy
became a favorite attraction at
the museum in the Louisville
Free Public Library, at 4th &
York.
Tchaenhotep’s History
• During the Ohio River
Flood of 1937, the
mummy was nearly
destroyed.
Tchaenhotep’s History
• Rising waters caused a piano to
fall on the mummy and, the head
became separated from the body.
• The mummy was later moved to
5th and York Streets and, in
1977, arrived at the present
location of West Main Street.
The mummy and coffin were on
continuous display there until early in
this century when they came to rest in
the collections storage areas of the
Louisville Science Center.
What Can we Salvage from The
Mummy?
Medical Imaging
Some Marvels…
X-Ray
Image Formation
A beam of X-rays is directed through a patient onto a film.
The film provides a measure of the ray attenuation in tissue.
Nov 8, 1895
Wilhelm Konrad Röntgen
reported discovery of new “rays”
(Nobel Prize in physics in 1901).
Jan 13, 1896
First clinical use of X-rays by 2
British doctors to find a needle
in a hand.
+ Excellent for imaging bones.
- No depth information, bad for soft tissue, excessive radiation
Sample X-Ray Slices
Computed Tomography (CT)
Image Formation
The object is viewed from a number of different angles and then a crosssectional image of it can be computed (reconstructed).
1965
G. Hounsfield (computer expert)
and A.M Cormack (physicist)
(Nobel Prize in Medicine in 1979).
+ Provide 3D anatomical information
+ Preserves topology (bones)
- Excessive radiation
- Not good for all soft tissues
Computed Tomography (CT)
• The object is viewed from a number
of different angles and then a crosssectional image of it can be
computed (reconstructed).
Sample CT Slices
CT Acquisition Techniques
slice-by-slice scanning
Spiral (volume) scanning
(Very Fast)
3D Reconstruction
Magnetic Resonance Imaging (MRI)
Image Formation
- Hydrogen nuclei (protons) under a strong magnetic field spin
in phase with one another and align with the field.
- Relaxed protons induce a measurable radio signal.
1952
F. Bloch and E. Purcel, extended by R. Ernst)
(Bloch & Purcel: Nobel Prize in Physics in 1952)
(Ernst: Nobel Prize in Chemistry in 1991)
Paul Luterberg: Nobel Prize in Physcis in 2004
For Basic MRI Research
+ Main modality for image guided surgery.
+ Superb ability to discriminate between
subtle differences in tissue characteristics.
+ Very safe.
- Less accurate for bone scanning.
Sample MRI Slices
Ultrasound (US)
Image Formation
An ultrasonic energy is propagated into the patient from a
transducer placed on the skin and back-scattered echo signal is
recorded by the same transducer.
1979: Samuel H. Maslak
+ Noninvasive
+ Clean & safe
+ In-expensive
- Noisy
- Gas filled and bony structures cannot be imaged
because they absorb ultrasound waves.
Positron Emission
Tomography
(PET)
Image Formation
- Detection of radiation from the emission of positrons.
1998-2001:
Dr. David Townsend and Dr. Ron Nutt.
+ Valuable technique for some diseases
and disorders.
+ Amount of radiation is small
- Invasive (inject radioactive material)
3D Model Building
Segmentation
CT
Segmentation
MRI
Segmentation
MRA
Multimodal
Registration
Fusion
3D Brain Models from MRI Scans
An MRI Scan
Fusion of Multiple scans
vascular tree
Structural Brain Model
Back to The Mummy….
X-ray
Capture the Data Base
•The team at Baptist East Hospital performed
a CT scan on the Tchaenhotep mummy’s
and a data base of images of the heard was
supplied on CDs.
• Each image consisted of 512x512 pixels
(picture elements).
•Each pixel in the image slice was
represented by a 16 bit grayscale value
giving a gray level range from 0 (completely
black) to 65535 (completely white).
CT IMAGES
Capture the Data Base
•The team at Baptist East Hospital performed
a CT scan on the Tchaenhotep mummy’s
and a data base of images of the heard was
supplied on CDs.
• Each image consisted of 512x512 pixels
(picture elements).
•Each pixel in the image slice was
represented by a 16 bit grayscale value
giving a gray level range from 0 (completely
black) to 65535 (completely white).
CT IMAGES
CT SCAN Slice
• Difference between the mummy’s CT
slice and a living person’s CT Slice.
<< Mummy
Normal >>
Registration of slices and 3D stack
• By reading the images into a
computer and stacking them,
a 3D volume of the CT scans
can be made, creating a
virtually 3D skull inside the
computer’s memory.
• The process required
aligning various features
from slice to slice =
Segmentation
•
•
•
The next stage is the process of segmentation
where we assign labels to each data that
declares if the voxel is bone tissue or air or
other tissue.
In this Segmentation we used a simple
thresholding method.
In the CT image air is black (or has a zero
value) and the bone tissue is white. We set a
range where any pixel above a value of 255 is
labeled
bone.
CT Image were all gray
levels are mapped to white.
CT Image
CT Image with gray
level values above 255
CT SCAN Slice
• Difference between the mummy’s CT
slice and a living person’s CT Slice.
<< Mummy
Normal >>
Reducing the Triangle Count
• The number of X,Y,Z coordinates
creating the ISO-surface is quite large.
• Our volume consists of 512x512x198 or
51,904,512 voxels and each voxel has an
X,Y,Z coordinate.
• If half of the volume is labeled bone,
then there are more than 25 million X,Y,Z
coordinates.
• We reduce this by using a process
called DECIMATION.
• Decimation reduces the number of
triangles which make up the ISO-Surface
by removing duplicate or unneeded
triangles.
Polydata Mapping
•Once the we have the triangles reduced,
two more actions are performed.
•First we create a surface for the
computer to display by filling the
triangles in a process we call polydata
mapping.
•Second, we create a stereo lithography
(STL) file for use by the rapid prototype
machine which creates the 3D plastic
model.
3D Reconstuction and STL Wire Mesh
•
•
We save only the bone voxels for our final virtual model’s
data base. ( voxels are 3d pixels )
Next we create a stereo lithography (STL) file for use by the
rapid prototype machine which creates the 3D plastic
model.
Generate STL file, 3D Reconstuction and
STL Wire
• We are then ready for the SLA process
in the rapid prototyping machine.
Summary Movie
End!