Mapping, registration and atlases IMAGE workshop breakout group

Mapping, registration and atlases
IMAGE workshop breakout group
Members of group
Derek Hill, London
Richard Baldock, Edinburgh
Dave Berry, Edinburgh
Tilak Ratnanather, Baltimore
Xavier Pennec, Nice
Denise Ecklund, Edinburgh
Vincent Breton, Clermont Ferrand
Aims of breakouts
• To generate written report about issues
• Make recommendations for future work
• Highlight areas that might benefit from
future research funding
• Make links with industrial activity
• Facilitate international collaboration
Breakout group sub-headings
• How do we make image registration grid services
• Can the grid provide a technology push?
• How should we represent mappings?
• Should we use grid-services for a major cross
validation of algorithms?
• How can, or should,atlases be shared?
• How could these services be used commercially
(eg: for drug discovery)
• What user interaction is required?
• Statistics of mappings
• How do we make image registration grid
services intraoperable?
– Do we need to devise an abstract model for
these services?
• Eg: what is a spatial transformation
• ITK is going some of the way in this direction and
illustrates some of the difficulties
• Can the grid provide a technology push
– New techniques that simultaneously analysis
– Treating time better
– User interaction
• How should we represent mappings?
– Definition of coordinate systems
– Representing diffeomorphisms and other types
of mappings
– Do we need an ontology?
• Should we use grid-services for a major cross
validation of algorithms?
– Compare with 1995 retrospective registration
evaluation project which used ftp for international
multicentre collaboration
– Do you need a “gold standard” to do this?
– Could we share the necessary data internationally?
• Two approaches:
– Test algorithms against standard data including
sensitivity to data perturbations
– Test data against algorithms
• Who would pay for CPU cycles?
• Compare results of new algorithms with those of
established algorithms eg: SPM
• How can, or should, atlases be shared?
– Component data for atlas
– Algorithms that form part of atlas
• We need to carefully define what we mean
by an atlas
– Is there an agreed definition for a static atlas?
– Is it an evolving representation of the state of
• How could these services be used
commercially (eg: for drug discovery)
– Regulatory approval?
– The grid could provide access to established
validated algorithms
– Mechanisms for licensing s/w on a per-use
User interface
• A user interface will be needed to interact with the
– Set parameters, use best practice parameters
– Customize to application
– Interact with the registration process, eg: to add prior
knowledge about corresponding features
• Tutorials
• Visualization of results: how do we visualize
mappings (application specific)
• Mapping statistics
– Statistics on deformations might be part of an
How do we overlap with other
• Visualization and data exploration
– We need visualization tools for interaction and viewing
• Image analysis, measurement and query
– How do we use queries to reason with mappings
generated by regn. algorithms?
– Metrics from mappings
– Metrics from registered images
• Data management, metadata, ontologies,
– We obviously need all of this stuff!
Issue of generalization
• Almost all headings in “registration” could
be applied to other image analysis
techniques eg: segmentations
Future work of this group
• Select sub-headings for detailed discussions
leading to recommendations
• What is easy to do, not easy to do, or dependent
on other activity?
• Can we identify the state-of-the-art in these areas?
• Can we facilitate international collaboration?
• Link our aspirations to the current state of grid
A registration test bed
• Registration is a core technology in medical
image analysis
• There is no one algorithm that solves all
• There continues to be substantial algorithm
• Registration needs to fit into many different
image analysis workflows
Scenario 1
• Prototyping a new application
New sort of data
New question
Want to find the right algorithm
Grid can be used to do large scale comparison
of different algorithms
Scenario 2
• “Production” image registration service
– Provides easy use for customers
• Application scientists eg: clinical research fellow
• Companies (eg: pharma)
• Healthcare organisations
Scenario 3
• Cross validation
– Grid services providing image registration
– Reference datasets
– Definition of how to to add a new registration service
or new data
– Can be used by researchers to compare algorithms prior
to publication
– Challenges to compare algorithms on new problems,
eg: one brought by a pharma company, new algorithms
Scenario 0
• To build a grid application to enable comparison
of registration algorithms
• Limited grid demonstrator
– Loose collaboration of resources, algorithms and
– At least 3 algorithms
– At least 3 data repositories (?include pathology)
– At least 3 compute resources
– At least 3 research teams
– Demonstrate expandability, heterogeneity
• Image file formats
– We could use the DICOM core fields
• Access to grid infrastructure
– Hardware
– Support and training to set it up
• Architecture
– Coordination
– Portal
– registry
More Obstacles
• Transformation format
– Could initially provide tutorial, example standard
transformation, i/o libraries
– Should we have a minimum subset of data eg: vector
field of resolution of original target image
– Origins etc…
• How do you quantify differences between
• Security and confidentiality
– We would start with anonymised data for which
suitable consent had been obtained
Way forward
• We want to keep it small so that things can
happen for scenario 0.
• We could keep it small by proposing it is
initially done with no funding.
• This needs to be application lead
• The primary aim is to answer scientific
questions about image registration
Partners and Roles
• INRIA linux cluster,
– already has a PhD student working on parallellising
registration algorithm,
– could probably generate interest in putting this on the grid.
• KCL & Imperial (IXI)
– Already implementing registration service
– Could assist with registry and portal (a month or so of effort
to do something)
• Hopkins
• Supercomputer on the grid running registration
• Others to give global coverage
• Set up email list – Sept 2003
• Invite key application groups to meeting at
MICCAI 2003, Montreal in November 2003
• Initial demonstration of concept, and
description of project for eHealth in January
• Need a grid technology support from NESC
and Clermont Ferrand