INTRODUCTION TO INTERACTIVE STATIONS / INTRODUCTION AUX

SESSIONS INTERACTIVES

Jean-Paul Soucy, MD, MSc, FRCP(c)Professeur titulaire de clinique, Radiologie, Université de MontréalMedical Director – PET UnitMcConnell Brain Imaging Centre, Montreal Neurological InstituteAdjunct Professor, Neurology and Neurosurgery, McGill UniversityAssociate Director, Bio-ImagingPERFORM Centre, Concordia University

Réunion Annuelle de l’ACMN/CANM Annual MeetingMontréal - 2015

There will be 15 cases to review.

All were sent for evaluation of a potential neurodegenerative condition (no epilepsy cases)

All have received a consensus clinical diagnosisbases on clinical presentation and evolution, imaging protocols, laboratory tests, etc.

Clinical information is presented as received.

Extra-cerebral accidental findings (if there are any)will not be discussed.

All cases will presented in a standard fashion:

1) All will have been co-registered (NOT spatially normalized) to:

a) The MNI_305 template , which comes from …

CAVEAT!

1) One brain2) 60 year old female subject3) Limited sampling

MNI305 Collin27 MNI152 lin. MNI152 n-lin.

Evans, A.C., Collins, D.L., Mills, S.R., Brown, E.D., Kelly, R.L., Peters, T.M., 1993. 3D statistical neuroanatomical models from 305 MRI volumes.

Proc IEEE-Nuclear Science Symposium and Medical Imaging Conference, pp. 1813–1817

All cases will presented in a standard fashion:

1) All will have been co-registered (NOT spatially normalized) to:

a) The MNI_305 (avg305) template

b) And to the icbm_avg_152_t1_tal_nlin_symmetric_VI_temporal

All cases will presented in a standard fashion:

1) All will have been co-registered (NOT spatially normalized) to:

a) The MNI_305 (avg305) template

b) And to the icbm_avg_152_t1_tal_nlin_symmetric_VI_tempora

2) All have been processed with Neurostat – 3D-SSP; only the “decreased” window is shown.

All cases will presented in a standard fashion:

1) All will have been co-registered (NOT spatially normalized) to:

a) The MNI_305 (avg305) template

b) And to the icbm_avg_152_t1_tal_nlin_symmetric_VI_temporal

All cases will presented in a standard fashion:

1) All will have been co-registered (NOT spatially normalized) to:

a) The MNI_305 (avg305) template

b) And to the icbm_avg_152_t1_tal_nlin_symmetric_VI_tempora

2) All have been processed with Neurostat – 3D-SSP; only the “decreased” window is shown.

3) Finally, you will have access to the attenuation correction/localization CT for each scan.

This type of approach represents the minimal level of pre-clinical reading processing that should be performed before interpreting scans!

All cases will presented in a standard fashion:

1) All will have been co-registered (NOT spatially normalized) to:

a) The MNI_305 (avg305) template

b) And to the icbm_avg_152_t1_tal_nlin_symmetric_VI_temporal

1) All will have been co-registered (NOT spatially normalized) to:

a) The MNI_305 (avg305) template

b) And to the icbm_avg_152_t1_tal_nlin_symmetric_VI_temporal

MUCH easier to read

F/u identical

2) All have been processed with Neurostat – 3D-SSP

Coleman, Neuroimaing Clin N Am 2005:

"It is likely that experienced individuals will be better than the computerized methods for detecting the abnormalities on the PET brain scan. In nuclear cardiology, it is shownthat experienced readers are more accurate than the computerized techniques …".

Also: Ebmeier, Adv Biol Psychiatry 2003, discussing such approaches with SPECT:

"SPM improves rater accuracy, especially for less experienced raters".

Which takes us to: Where does SPECT stand in this scheme?

Cerebral 18F-FDG PET certainly is neither available everywhere, nor reimbursed for by every province, whereas SPECT rCBF studies are.

However, SPECT rCBF studies generally significantly underperform as compared to 18F-FDG PET for the diagnosis and classification of neurodegenerative conditions associated with cognitive disorders …

Where does SPECT stand in this scheme?

Cerebral 18F-FDG PET certainly is neither available everywhere, nor reimbursed for by every province, whereas SPECT rCBF studies are.

However, SPECT rCBF studies generally significantly underperform as compared to 18F-FDG PET for the diagnosis and classification of neurodegenerative conditions associated with cognitive disorders …

Overall however, NO study has ever found SPECT to be superior to PET in that field (at best equal, but with low PET accuracy), whereas SOME have found the opposite,by a large margin. Therefore, …

29 cm

20 cm

There might be some hope for SPECT …

Hoffman Phantom

MRI

HR SPECT

Standard 3 detector

SPECT

18FDG PET 99mTc-HMPAO SPECT

Maybe that in a few years …

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Fig 2: peak-matched TACs and

deconvolved hemispheric TACs

with regressed rCBF values

Moreover, SPECT-rCBF studies with

99mTc ECD/HMPAO can be quantified …

Soucy, 2007, 2008

The final report presents rCBF values for 116 predefined regions,

which can be modified at will (combined, redefined, …)

Soucy, 2007, 2008

For now, we’ll only review 18F-FDG (only clinically available agent)

PET studies

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Have fun reading those studies!I’ll see you again Sunday.

For MOC purposes at the Royal College:

- The introduction and the review sessions should be listed under Section 1 (respectively 30 and 45 minutes of credits)

- The reading session is rated at 1 hour under Section 3, and therefore will give you 4.5 hours of credits