Transcript Document

QIBA
Proposed Phase 1A Project
V5.0
QIBA Phantom Subgroup
N Petrick
RSNA QIBA Phantom Group
November 13, 2008
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Outline of proposal
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Modified 1A reader study
Outstanding issues
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N Petrick
RSNA QIBA Phantom Group
November 13, 2008
Draft 1A: Study objective
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Measure intra- and inter reader bias
and variability on phantom lesions
for:
 Uni-dimensional size measurement
 Semi-automated 3D volumetric
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measure
Compare with fullyNotautomated
going to size for specific effect or
significance but just report as pilot
algorithm?
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N Petrick
RSNA QIBA Phantom Group
November 13, 2008
Draft 1A: Nodule/scan dataset
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Nodules (10 attached nodules)
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-10 & +100HU
10, 20 mm spheres
10 mm ovoid, lobulated, spiculated
Okay
Scanner
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Philips 16 slice
Exposure (120 kVp):
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100 mAs okay
100 mAs
Slice thickness (50% overlap)
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0.75 & 5.0 mm slices
0.75 mm slices okay
Recon kernel
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Standard/medium (Still on table: Detail/Lung kernel)
Pitch
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1.2
2 repeat scans
40 segmentations in set
Okay
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N Petrick
RSNA QIBA Phantom Group
November 13, 2008
Draft 1A: Study Protocol
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Reader:
 6 RadPharm radiologists
 Software:
Need to determine this?
Wendy will visit RadPharm and
provide more info next week.
 In-house review software (Siemens?)
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Semi-automated 3D volume software
Uni-dimensional measure (RESIST)
 Which fully automated software?
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N Petrick
RSNA QIBA Phantom Group
November 13, 2008
Draft 1A: Study Protocol
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Reading session:
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Readers read all cases in 2 different reading session
 Random ordering
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One-dimensional measure
Semi-automated segmentation
Session separated by 3 week?
Include duplicate cases within each read session (1/3-1/2
of cases for intra-reader estimates)
 Any time restrictions?
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 Probably not
Any specific instructions?
 Probably not
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N Petrick
RSNA QIBA Phantom Group
November 13, 2008
Draft 1A: Analysis
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Okay
Estimate intra- and inter-reader
variability in the different volume
estimate
 Estimate bias from known truth
 Estimate variability
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Compare the bias and variability with
the different methods
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N Petrick
RSNA QIBA Phantom Group
November 13, 2008
Draft 1A: Outstanding issues
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Objective-Okay
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This is pilot, no sizing will be done
 May want to at least look at this to see if we have a
reasonable study design
Data collection: Okay
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+100 HU (all 1A scanner settings)
 Acquired: 10 mm & 20 mm sphere, ovoid, spic, lob
-10 HU (all 1A scanner settings)
 Acquired: 10 mm & 20 mm sphere
 Missing: 10 mm ovoid, spic, lob (Est: 12/01/08)
10 mm aspherics okay
100 mAs okay
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N Petrick
RSNA QIBA Phantom Group
November 13, 2008
Draft 1A: Outstanding issues
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Readers-Okay
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6 okay (base on expected effect size?)
Software-Open source option is available to use
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Need to finalize which software
Contact Bob Ford to discuss
Study Issues
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GUI
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AVT designed interface?
Standard PACs interface?
How will nodule locations be provided to readers?
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Full scans with nodule centers
Extracted ROIs
Can cases be directly uploading into PACs?
How to randomize cases during reading sessions
Data format for segmentations/measurements
Truth/scoring format
ROIs or full scans with lesion marked
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N Petrick
RSNA QIBA Phantom Group
November 13, 2008
Draft 1A: Pilot Study
 Study protocol
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9 nodules for segmentation
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3 nodules with each segm. method
2 readers
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Needs to be determined
 2 slice thickness
 10 mm -10 HU, sphere, spiculated
 10 mm, +100 HU, lob., ovoid
 20 mm, +100 HU, sphere
 Timeframe
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N Petrick
RSNA QIBA Phantom Group
November 13, 2008
Draft 1A: Outstanding issues
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Statistical
 Can we measure intra-reader variance
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with only 2-4 repeat reads?
What effect size can we distinguish?
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Again, may want to explore but this study
will only measure as in a pilot
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N Petrick
RSNA QIBA Phantom Group
November 13, 2008
Draft 1A: Outstanding issues
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Other issues
 Need to define QIBA publication policy
 Determine research team makeup
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Lisa Kinnard & Marios Gavrielides from
FDA lab
 Other Issues
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N Petrick
RSNA QIBA Phantom Group
November 13, 2008
Draft 1A: Submissions
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Conferences
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ASCO
 5/29-6/2/09 Orlando
 Abstract Deadline: 1/6/09
RSNA
 End Nov, 2009, Chicago
 Abstract Deadline: 4/15/09
Journal
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NEJM!
Radiology
Oncology journals?
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N Petrick
RSNA QIBA Phantom Group
November 13, 2008
Action Items
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Rick Avila to follow-up with caBIG
AVT group
Rick Avila to lead effort of Lesion
Ground Truth subgroup
Reporting Mechanism to be
discussed at later date
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N Petrick
RSNA QIBA Phantom Group
November 13, 2008
Work Items and workgroup
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??
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N Petrick
RSNA QIBA Phantom Group
November 13, 2008