Transcript osteoarthritis

Imaging biomarkers for osteoarthritis
research
Jeff Prescott, Mark Swanson, Tom Best,
Furqan Haq, Rebecca Jackson, Metin Gurcan
Imaging biomarkers for osteoarthritis
research
• Imaging biomarkers
• Osteoarthritis (OA)
• OA and the
quadriceps muscles
• OA and the
meniscus
• Imaging biomarkers
• Osteoarthritis (OA)
• OA and the quadriceps muscles
• OA and the meniscus
Imaging biomarkers
• Any anatomic, physiologic, biochemical,
or molecular parameter detectable with
one or more imaging methods used to
help establish the presence and/or
severity of disease1.
1Smith,
et al (2003)
Imaging biomarkers
• Any anatomic, physiologic, biochemical,
or molecular parameter detectable with
one or more imaging methods used to
help establish the presence and/or
severity of disease1.
1Smith,
et al (2003)
Applications of imaging biomarkers
• Improved diagnosis and tracking of
disease, especially chronic diseases
– OA, heart disease, Alzheimer’s, diabetes
• Drug and medical product development
– Faster, less expensive preclinical testing
and clinical trials
• Imaging biomarkers
• Osteoarthritis (OA)
• OA and the quadriceps muscles
• OA and the meniscus
Osteoarthritis (OA)
• OA most common
cause of disability in
U.S.2
– More prevalent than
heart disease and
diabetes combined
• Costs $128 billion
annually in medical
expense and lost
earnings
2Osteoarthritis
Normal
public health agenda, Osteoarthriis policy and communications working group
OA
• Imaging biomarkers
• Osteoarthritis (OA)
• OA and the quadriceps muscles
• OA and the meniscus
OA and the quadriceps muscles
Vastus
intermedius (VI)
• Quad muscle weakness Vastus
associated with OA3-5 lateralis (VL)
• Quad muscle crosssectional area (CSA) on
MRI correlated with
strength6
• Is quad CSA a
“biomarker” of OA?
3Overend,
et al (1992); 4Rice, et al (1989); 5Goodpaster, et al (2000); 6Klein, et al (2001)
Rectus
femoris (RF)
Vastus
medialis (VM)
Clinical significance
• Treatment
– Should physical
therapy focus on
strengthening
particular quadriceps
component?
• Prevention
– Detect high risk
patients, early stages
of disease
Challenges in automated
segmentation
• Lack of delineating
landmarks
• High contrast
intramuscular
adipose tissue
• Flow artifacts
• Bias fields
Why automated segmentation?
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4,796 volunteers in OAI study
4 thigh scans
15 slices per scan
2 thighs per scan
4 muscles per quad
2,302,080 separate segmentations!!
Results
• Imaging biomarkers
• Osteoarthritis (OA)
• OA and the quadriceps muscles
• OA and the meniscus
OA and the meniscus
• The meniscus may
modify development
and progression of
OA
• The meniscus
– Reduces stress on
the cartilage
– Lubricates the joint
– Contributes to joint
stability
Anterior horn
Body
Posterior horn
Semi-automated segmentation
results
• User inputs
– a single seed point
– the range of slices to
segment
• Algorithm segments
according to
intensity and
anatomical
constraints