Transcript Wideband SSFP

Medical Imaging
• X-ray
• Fluoroscopy
• Computerized Tomography
(CT Scan)
• PET Scan
• Ultrasound
• Magnetic Resonance Imaging
• Biophotonics
X-RAYS
X-ray
source

(x-ray attenuation)
OPAQUE:
Bone, Iodinated contrast agents
Shadow
Chest X-Ray
X-Ray of a murder victim killed with 30 nails
Normal Hand X-Ray
Rheumatoid Arthritis Hand X-Ray
Knee Joint X-Ray
Broken Neck X-Ray
Swollowed Scissors X-Ray
DOH!!
Fluoroscopy
Fluoroscopy is an examination of the body and deep
structures of the body by x-ray, using the fluoroscope.
Fluoroscopic X-Ray images the gastro-intestinal system and
specialized bodies systems.
The advantage of Fluoroscopic x-ray over conventional xray is that you can view in real time on a television monitor the
image. This means that movement of the peristalsis and
normal function of the body's systems can be captured and
recorded on videotape or videodisc.
Because fluoroscopy involves the use of x-rays, ionizing
radiation, all fluoroscopic procedures pose some health risks.
The most commonly used x-ray dye is barium sulfate, a
white-chalky substance.
Barium Fluoroscopy
Compare the image of the normal heart on the LT. with the image on
the Rt.. In the Rt. image you see a patient with congestive heart
failure whose heart has lost its ability to pump blood efficiently. The
heart on the Rt. significantly enlarged, a key indicator of heart failure.
Fluoroscopy X-Ray – Dog Neck and Shoulder
Computerized Tomography (CT)
X-ray
source
x,y)
(x-ray attenuation)
Collect projections at all angles
Digital Reconstruction
Shadow
CT Scan - Heart
CT Scan – 3D of various views of the Heart
Nuclear medicine (PET Scans)
PET = Positron Emission Tomography
• PET scanning is used to detect cancer, as well as a number of
cardiovascular and neurological abnormalities.
• Cancer cells, for example, have a much higher level of
metabolic activity than normal cells. PET scanning detects that
increased metabolic rate and can therefore:
• Show whether a tumor is benign (non-cancerous) or malignant
(cancerous)
• Help doctors determine the extent of disease (staging)
• Illustrate metastatic disease (spread)
• Help doctors evaluate the effectiveness of chemotherapy
Measures uptake of radio-labeled materials (biochemistry).
Images reflect function not anatomy.
PET Scan – Tumurs before
Chemotherapy (Lt.) and after (Rt.)
PET Scan
PET Scan - cancer of the head and neck with
extensive metastatic disease
PET Scans can detect metabolic changes in different tissue types
• Certain neurological disorders have characteristic
metabolic changes. These are readily apparent on
PET images. Alzheimer’s disease, for example, has a
unique appearance on PET scans. This appearance
can differentiate Alzheimer’s from other forms of
dementia, such as Pick’s disease, and give the
patient earlier access to appropriate treatments.
• In cardiovascular disease, PET images provide
information about blood flow and the presence of
damaged muscle tissue. This information is key to
planning appropriate treatments and disease
management.
PET scan images superimposed on MRI scan images shows a
healthy medical student's brain function when performing
arithmetical tasks at the same time as being exposed to speech.
PET Scan of the Brain of a 20 yr old man (Lt.) vs 80 yr
old man (Rt.)
Your Brain on Drugs (the red areas indicate
glucose uptake (= metabolism and brain function))
Ultrasound
r(x,y,z)
acoustic reflectivity
Propagate pulse and receive reflection
Compute position and velocity (Doppler shift)
2D
3D
QuickTime™ and a
Microsof t Video 1 decompressor
are needed to see this picture.
Ultrasound of a normal human uterus
Ultrasound of Human gall bladders
Magnetic Resonance Imaging (MRI)

MRI is one of the most sophisticated imaging tools
in modern medicine due to its ability to produce
images that show finer details.
 It provides excellent differentiation between
various types of soft tissues compared to radiographs
(x-rays and CT).
 MRI can be used to visualize the brain, spinal cord,
eyes, nasal cavities, inner ears, joints, and bones
without injecting any contrast material.
 It is the most sensitive imaging study for early
disease detection and cancer staging,
• Advantages:
–
–
–
–
Excellent / flexible contrast
Non-invasive
No ionizing radiation
Arbitrary scan plane
• Research:
– New contrast mechanisms
– Fast imaging
MRI Systems
$2-3 million
MRI – Section through head
MRI – Cross Section of Head
f-MRI – Where in the brain is hand/eye
coordination?
MRI – Neck Region
MRI – Knee Joint
Mammogram (X-Ray) vs MRI
MRI of Blood Flow in the Brain
MRI – Dog Skull
Biophotonics
• What Will Biophotonics Do?
• Biophotonics offers the ability to diagnose and
monitor disease nearly at the speed of light, based on
the way it interacts with tissue. With biophotonics,
healthcare professionals will know in moments what
before took hours or days with traditional tests,
enabling treatment to begin immediately. Future uses
of this technology will severely minimize, and in some
cases virtually eliminate, the hospital time and long
recovery periods that current procedures require.
Biophotonics also allows for studying human tissue at
the cellular and molecular level for the purposes of
detecting, diagnosing and monitoring disease.
Exposure of chicken embryos to laser light to detect changed
in development and stages of cell specialization/differentiation
Imaging cerebral blood flow in mice with
skull left intact