Agenda:

- New benchmark ICC and Dice’s

- Training set for Naïve

- Beta testers proposals

- Congress presentations

XII PMT meeting – September 26, 2012

Benchmark Images

ADNI scans: 2 x 5 Scheltens’s atrophy score x 2 sides

x 2 magnet strengths (1.5-3T)Total per rater: 40 hippos

5 Master Tracers’ segmentations:

Corrections after check for overlapping discrepanciesImproved Harmonized Protocol (HP) in many points

HP re-sent to panelists

Benchmark Images

Overlapping agreement Volume ICCs

1.5T images: 0.73

3T images: 0.75

Maximum level for

human tracers???

Left Hippocampus Right Hippocampus

Intra-rater 1.5T vs 3T (n=10)

MB 0.981 (0.928-0.995) 0.986 (0.776-0.997)

RG 0.968 (0.879-0.992) 0.974 (0.902-0.994)

GP 0.943 (0.335-0.989) 0.968 (0.541-0.994)

LA 0.966 (0.819-0.992) 0.971 (0.818-0.993)

DW 0.981 (0.930-0.995) 0.986 (0.944-0.997)

Inter-rater (n=10)

1.5T 0.957 (0.881-0.988) 0.971 (0.916-0.992)

Inter-rater (n=10)

3T 0.943 (0.791-0.986) 0.962 (0.863-0.990)

Training set for Naïve Tracers

- Liana Apostolova (7T)

-Brescia - Normative Archive (1.5 and 3T; 12 images (different severity) per magnet field strength?)

? TIMING for Certif. Platform ?

Will need to recap with available tracers in the 20 centres

Publication Policy

STANDARD FORM for submission:

TITLE of PROPOSAL:PI / CENTRE:AIM of the PROJECT:METHODS of the PROJECT:WHAT IS ASKED to the SC of the HARMONIZED HIPPOCAMPAL PROTOCOL WHAT IS OFFERED to the HARMONIZED HIPPOCAMPAL PROTOCOL PROJECT/COMMUNITY:

Masami Nishikawa (comparison of VSRAD performance; segmentation of human phantoms x HP)

Lei Wang (library of atlases; validation vs other algorithm/s x HP?)

Ronald Pierson (train ANN of Brain Image Analysis, LLC validation vs other algorithm/s x HP?)

Beta tester submissions

Lei Wang: use of “local” labels

“construction of a library of atlases for the purposes of mapping MR scans such as the ADNI data set”

Asks: use of label already segmented based on local protocol

Asks: to be informed as to when harmonized labels are available

Offers: solving the conversion of MultiTracer files into more common format

Beta tester submissions

Masami Nishikawa

Project aim: to validate the new version of VSRAD (Voxel-based Specific Regional analysis system for Alzheimer’s Disease), comparing it versus the Harmonized Protocol as the gold standard method to manually measure hippocampal volume.

Asks: Harmonized Protocol

Offers: Hippocampal segmentations on 3 healthy volunteers scanned twice by the 7 different machines will contribute for the validation of the Harmonized Protocol.

Beta tester submissions

Ronald Pierson

Project aim: Compare the results of the current hippocampal segmentation with other hippocampal definitions using BRAINS (Brain Research: Analysis of Images, Networks, and Systems)

Asks: Harmonized Protocol

Asks: ADNI IDs of benchmark subjects

Offers: not clear

Beta tester submissions

- CTAD (October, 29-31 2012)Definition of the Harmonized Protocol for Hippocampal Segmentation

- DGPPN Symposium 2012 Berlin (Andreas Fellgiebel)Segmentation of the hippocampus: Towards a joint EADC-ADNI harmonized protocol

- AAN 2013 EADC-ADNI Benchmark Images of Harmonized Hippocampal Segmentation

Congress Presentations

Papers describing the project

Survey of protocols (preliminary phase; published, JAD 2011)Operationalization (preliminary phase; I revision, Alzheimer’s & Dementia, MS n. ADJ-D-12-00094)

Axes check short report (Brescia Team, in progress)Delphi consensus (Brescia Team, in progress)Master tracers’ practice and reliability (Brescia Team, in progr)

Development of certification platform (Duchesne and coll)Validation data (Brescia Team – companion paper 1)Protocol definition (Brescia Team – companion paper 2)Validation vs pathology (TBD)

DO

NE

IN P

RO

GR

ES

S P

LA

NN

ED

VALIDATION VS CURRENT PROTOCOLSASSESSMENT OF SOURCES OF

VARIANCE TRAINING SET DEVELOPMENT

VALIDATION VS PATHOLOGY

GOLD STANDARD

Harmonized ProtocolADNI scans: 2 x 5 Scheltens’s

atrophy score x 2 sides x 2 magnet strengths (1.5-3T)

Total per rater: 40 hippos

Harmonized ProtocolADNI scans: 2 sides x 5 Scheltens’s atrophy scores

x 3 time points (bl-1y-2y) x 3 scanners (+ retracing @ bl)

x 2 magnet strengths (1.5-3T)Total per rater: 240 hippos

Assessment of variance due to rater and center

Local ProtocolADNI scans: 2 x 5 Scheltens’s atrophy scores

x 2 sides x 2 magnet strengths (1.5-3T)

Harmonized ProtocolADNI scans: 2 x 5 Scheltens’s atrophy score x

2 sides x 2 magnet strength (1.5-3T)Total per rater: 40 hippos Harmonized Protocol:

Pathological datasets: Mayo Clinic and NYU

Total: about 40 hippos

TrainingADNI scans: 10 at 1.5T x 2 sides x 7

SUs x 2 tracing roundsTotal per rater: 40 hippos

20 naïve tracers 5 master tracers 1 tracer

REFERENCE PROBABILISTIC MASKS

with 95% C.I.

QUALIFICATION QUALIFICATION

Best 5 naïve tracers

Assessment of variance due to side, trace-retrace, atrophy, time, scanner, rater

TRAINING SET

Assessment of agreement with volume on pathology or ex vivo

MRI and correlation with neuronal density

GANTT

CSF exclusion (n. labels)

using the same CSF label containing two (or more) separate CSF area on the same slice, for each hippocampus

using a single CSF label to exclude a large CSF pool