aan –toronto, april 11, 2010
DESCRIPTION
AAN –Toronto, April 11, 2010. Development of a harmonized protocol for hippocampal tracing An EADC-ADNI joint effort METHODS. METHODS. Operationalization of protocols’ differences and extraction of tracing units Quantification of tracing units’ features Harmonized protocol. - PowerPoint PPT PresentationTRANSCRIPT
AAN –Toronto, April 11, 2010
Development of a harmonized protocol for hippocampal tracing
An EADC-ADNI joint effort
METHODS
Operationalization of protocols’ differences and extraction of tracing units
Quantification of tracing units’ features
Harmonized protocol
METHODS
Selection criteria
i) Being based on 3D T1 MRI with field strength greater than 1 Tesla
ii) Providing explicit description of landmarks for tracing of hippocampal borders
iii) Being validated on AD/MCI samples, or being widely adopted in the literature about AD.
OPERATIONALIZATIONSelection of segmentation protocols
Plane of tracing: AC-PC line;
Normalization to the Talairach space
Tracing start from the tail of
hippocampus to the hippocampal head
In the following slices, you can find the
hippocampal tracing on consecutive
coronal slices (1.5T) of the control subject and AD patient according to Pruessner's criteria
Areas explicitly excluded
Most anterior slice
Andreas-Retzius gyrus (ARG), the part
of the FG that is adjacent to ARG, crus
of fornix
slice w here one of the follow ing is visible: alveus,
temporal horn of lateral ventricle (uncal recess) or
amygdala
Lateral border Inferior border Medial border
HE
AD temporal horn of
lateral ventricle (uncal recess)
uncal cleft (if visible) CSF of ambient cistern
BO
DY temporal horn of
lateral ventricle (uncal recess)
White matter of the parahippocampal
gyrusCSF of ambient cistern
TA
IL
Discrimination of HT from FG and crus of fornix using arbitrary
borders
adjacent w hite matter atrium of lateral ventricle
Areas explicitly included
CA regions, dentate gyrus, subiculum,
alveus, f imbria, part of the fasciolar gyrus (FG)
BOUNDARIES
Discrimination of HT from ARG using arbitrary borders
Most posterior slice
slice w here an ovoid mass of gray matter started to appear
inferomedially to the trigone of the lateral ventricle
Superior border
temporal horn of lateral ventricle (uncal recess) and alveus
superior excess of the quadrigeminal cistern
OPERATIONALIZATIONProtocols’ features extraction
Tracings carried out on a control and an
AD subject from the ADNI dataset
Tracings sent to the Authors for correction or approval
OPERATIONALIZATIONPrototypical tracings
CTRL
Most posterior slice : slice where an ovoid mass of gray matter (1) started to appear inferomedially of the atrium of lateral ventricle (2)
Sagittalview
2= Atrium of lateral ventricle4= Parahippocampal gyrus5= Gyrus dentatus6= Cornu Ammonis7= Gyrus fasciolaris8= Gyrus of Andreas-Retzius9= Isthmus
The fornix can be excluded by a horizontal line (in fuchsia) from the superior border of the quadrigeminal cistern (3) to the lateral ventricle (2).Part of gyrus fasciolaris (7) and of Andreas-Retzius gyrus (8) can be excluded by a vertical line (in red) from the medial end of the lateral ventricle (2) down to the parahippocampal gyrus (4).
AD
Most posterior slice : slice where an ovoid mass of gray matter (1) started to appear inferomedially of the atrium of lateral ventricle (2)
2= Atrium of lateral ventricle4= Parahippocampal gyrus5= Gyrus dentatus6= Cornu Ammonis7= Gyrus fasciolaris8= Gyrus of Andreas Retzius9= IsthmusSagittal
view
In AD subjects the cerebral structures are atrophic, lateral ventricle (2) and ambient cistern (3) result enlarged. Therefore,the lines used to exclude the gyrus fasciolaris, the Andreas-Retzius gyrus and the fornix do not intersect the hippocampal tail. That being so, is there another way to exclude the gyrus fasciolaris, the Andreas-Retzius gyrus and the fornix in these subjects?
Areas explicitly excluded
Most anterior slice
Andreas-Retzius gyrus (ARG), the part
of the FG that is adjacent to ARG, crus
of fornix
slice w here one of the follow ing is visible: alveus,
temporal horn of lateral ventricle (uncal recess) or
amygdala
Lateral border Inferior border Medial border
HE
AD temporal horn of
lateral ventricle (uncal recess)
uncal cleft (if visible) CSF of ambient cistern
BO
DY temporal horn of
lateral ventricle (uncal recess)
White matter of the parahippocampal
gyrusCSF of ambient cistern
TA
IL
Discrimination of HT from FG and crus of fornix using arbitrary
borders
adjacent w hite matter atrium of lateral ventricle
Areas explicitly included
CA regions, dentate gyrus, subiculum,
alveus, f imbria, part of the fasciolar gyrus (FG)
BOUNDARIES
Discrimination of HT from ARG using arbitrary borders
Most posterior slice
slice w here an ovoid mass of gray matter started to appear
inferomedially to the trigone of the lateral ventricle
Superior border
temporal horn of lateral ventricle (uncal recess) and alveus
superior excess of the quadrigeminal cistern
For each protocol: features extraction, tracing and author’s certification
AD
CTRL
X 10
OPERATIONALIZATIONAuthors’ check
OPERATIONALIZATIONExtraction of similarities and differences
Areas explicitly excluded
Most anterior slice
choroid plexis of inferior horn, amygdala
level at w hich the alveus distinguishes the amygdala
from hippocampus
Lateral border Inferior border Medial border
HE
AD inferior horn of the
lateral ventriclew hite matter joining the parahippocampal gyrus
angular bundle
BO
DY
same as head same as head same as head
TA
IL same as head same as head same as head
BOUNDARIES
Areas explicitly included
portion of subiculum, CA f ields
same as head
Most posterior slice
slice in w hich the fornix appeared as a solid w hite line through the collateral trigone
Superior border
inferior horn of the lateral ventricle
same as head
Harmonized language
Reduction of redundancy
Tracing units and subunits
Areas explicitly excluded
Most anterior slice
Andreas-Retzius gyrus (ARG), the part
of the FG that is adjacent to ARG, crus
of fornix
slice w here one of the follow ing is visible: alveus,
temporal horn of lateral ventricle (uncal recess) or
amygdala
Lateral border Inferior border Medial border
HE
AD temporal horn of
lateral ventricle (uncal recess)
uncal cleft (if visible) CSF of ambient cistern
BO
DY temporal horn of
lateral ventricle (uncal recess)
White matter of the parahippocampal
gyrusCSF of ambient cistern
TA
IL
Discrimination of HT from FG and crus of fornix using arbitrary
borders
adjacent w hite matter atrium of lateral ventricle
Areas explicitly included
CA regions, dentate gyrus, subiculum,
alveus, f imbria, part of the fasciolar gyrus (FG)
BOUNDARIES
Discrimination of HT from ARG using arbitrary borders
Most posterior slice
slice w here an ovoid mass of gray matter started to appear
inferomedially to the trigone of the lateral ventricle
Superior border
temporal horn of lateral ventricle (uncal recess) and alveus
superior excess of the quadrigeminal cistern
axial + coronal + sagittal
Cornu Ammonis, subiculum, vertical digitation alveus and fimbria
Medial border Lateral border
HE
AD
Gyrus ambiensidentified by the
contrast of the WM or CSF
BO
DY
The medial border of the HC w as continued w ith a straight horizontal line (marking the inferior border
of CA and subiculum) across the cortex of the PHG. The cortex below this line w as considered
the PHG, and the cortex above this line w as included as a part of the HC
identified by the contrast of the WM
or CSF
TA
IL
The medial border of the HC w as continued w ith a straight horizontal line (marking the inferior border
of CA and subiculum) across the cortex of the PHG. The cortex below this line w as considered
the PHG, and the cortex above this line w as included as a part of the HC
identified by the contrast of the WM
or CSF
WM of parahippocampal gyrus
WM of parahippocampal gyrus
Superior border
identified by the contrast of the WM or CSF
identified by the contrast of the WM or CSF
WM of parahippocampal gyrus (PHG)
Areas explicitly included Plane tracing
identified by the contrast of the WM or CSF, and Thalamus and
caudate nucleus
Most posterior slice
coronal section in w hich the hippocampus first appeared
adjacent to the trigone of lateral venticle
Areas explicitly excluded
Most anterior slice
the separation of amygdala and hippocampal head w as
facilitated by sagittal and transverse view s
Inferior border
BOUDARIES
Line outlining the contour of white matter of parahippocampal gyrus [Pa,S]
Orizontal line from the highest medial point of the parahippocampalWM to the cistern [B,H,J¥]
Oblique line with same inclination of parahippocampalWM, connecting the inferior part of the subiculum to the quadrigeminal cistern [K,L,M¥]
45° line connecting the most inferior part of the subiculum medially to the cistern (head and body) [Pr]
vertical line from the CA to the WM of the parahippocampalgyrus [C]
Separation subiculum/enthorinal cortex
Horizontal line from the superior border of the quadrigeminal cistern to the lateral ventricle (tail) [Pr]
Upper border of alveus/fimbria[C,J,L,M,Pr]
Lower border of alveus/fimbria[B,H,K,Pa,S]
Superior border
Where gray matter is visible inferomedially to the trigone of the lateral ventricle [H,M•,Pa•,Pr]
Where the crura of the fornicesare seen in full profile on both sides [J,S]
Where crus of fornix is visible in full profile [C,K,L]
Where inferior and superior colliculiare jointly visualized [B]
Most posterior slice
AC-PC line [H,K,M,Pa,Pr]Axis of hippocampus [B,C,J,L,S]
Plane of tracing
Line outlining the contour of white matter of parahippocampal gyrus [Pa,S]
Orizontal line from the highest medial point of the parahippocampalWM to the cistern [B,H,J¥]
Oblique line with same inclination of parahippocampalWM, connecting the inferior part of the subiculum to the quadrigeminal cistern [K,L,M¥]
45° line connecting the most inferior part of the subiculum medially to the cistern (head and body) [Pr]
vertical line from the CA to the WM of the parahippocampalgyrus [C]
Separation subiculum/enthorinal cortex
Horizontal line from the superior border of the quadrigeminal cistern to the lateral ventricle (tail) [Pr]
Upper border of alveus/fimbria[C,J,L,M,Pr]
Lower border of alveus/fimbria[B,H,K,Pa,S]
Superior border
Where gray matter is visible inferomedially to the trigone of the lateral ventricle [H,M•,Pa•,Pr]
Where the crura of the fornicesare seen in full profile on both sides [J,S]
Where crus of fornix is visible in full profile [C,K,L]
Where inferior and superior colliculiare jointly visualized [B]
Most posterior slice
AC-PC line [H,K,M,Pa,Pr]Axis of hippocampus [B,C,J,L,S]
Plane of tracing
OPERATIONALIZATIONExtraction of similarities and differences
Areas explicitly excluded
Most anterior slice
choroid plexis of inferior horn, amygdala
level at w hich the alveus distinguishes the amygdala
from hippocampus
Lateral border Inferior border Medial border
HE
AD inferior horn of the
lateral ventriclew hite matter joining the parahippocampal gyrus
angular bundle
BO
DY
same as head same as head same as head
TA
IL same as head same as head same as head
BOUNDARIES
Areas explicitly included
portion of subiculum, CA fields
same as head
Most posterior slice
slice in w hich the fornix appeared as a solid w hite line through the collateral trigone
Superior border
inferior horn of the lateral ventricle
same as head
Areas explicitly excluded
Most anterior slice
Andreas-Retzius gyrus (ARG), the part
of the FG that is adjacent to ARG, crus
of fornix
slice w here one of the follow ing is visible: alveus,
temporal horn of lateral ventricle (uncal recess) or
amygdala
Lateral border Inferior border Medial border
HE
AD temporal horn of
lateral ventricle (uncal recess)
uncal cleft (if visible) CSF of ambient cistern
BO
DY temporal horn of
lateral ventricle (uncal recess)
White matter of the parahippocampal
gyrusCSF of ambient cistern
TA
IL
Discrimination of HT from FG and crus of fornix using arbitrary
borders
adjacent w hite matter atrium of lateral ventricle
Areas explicitly included
CA regions, dentate gyrus, subiculum,
alveus, f imbria, part of the fasciolar gyrus (FG)
BOUNDARIES
Discrimination of HT from ARG using arbitrary borders
Most posterior slice
slice w here an ovoid mass of gray matter started to appear
inferomedially to the trigone of the lateral ventricle
Superior border
temporal horn of lateral ventricle (uncal recess) and alveus
superior excess of the quadrigeminal cistern
Plane of tracing
Axis of hippocampus [B,C,J,L,S]
AC-PC line [H,K,M,Pa,Pr]
Most posterior slice
Where inferior and superior colliculi are jointly visualized [B]
Where crus of fornix is visible in full profile [C,K,L]
Where the crura of the fornices are seen in full profile on both sides [J•,S]
Where gray matter is visible inferomedially to the trigone of the lateral ventricle [H,M•,Pa•,Pr]
Superior border
Lower border of alveus/fimbria [B,H,K,Pa,S]
Upper border of alveus/fimbria [C,J,L,M,Pr]
Horizontal line from the superior border of the quadrigeminal cistern to the lateral ventricle (tail) [Pr]
Separation subiculum/enthorinal cortex
vertical line from the CA to the WM of the parahippocampal gyrus [C]
45° line connecting the most inferior part of the subiculum medially to the cistern (head and body) [Pr]
Oblique line with same inclination of parahippocampal WM, connecting the inferior part of the subiculum to the quadrigeminal cistern [K,L,M¥]
Orizontal line from the highest medial point of the parahippocampal WM to the cistern [B,H,J¥]
Line outlining the contour of white matter of parahippocampal gyrus [Pa,S]
Operationalization of protocols’ differences
Quantification of tracing units’ features
Harmonized protocol
METHODS
Contribution to hippo volume in control and AD
Effect on re-test variability
Contribution to differences between AD and controls
QUANTIFICATION OF TRACING UNITS’ FEATURES
Operationalization of protocols’ differences
Quantification of tracing units’ features
Harmonized protocol
METHODS
Participants to a Delphi panel based on:
expertise in hippocampal anatomy
manual tracing scientific production
Assisted decisions based on:
Low variability, highly informative.. ..included in harmonized protocol
High variability, little informative.. ..excluded from harmonized prot
HARMONIZED PROTOCOL
Validation with neuropathological data
Comparison with currently used protocols
Public tracings and probability maps
Standard environment for tracing, learning, and certification
HARMONIZED PROTOCOLValidation & implementation