HAI Book 2020 - Dec 18B

51

Keywords: Alzheimer’s disease, amyloid PET imaging
15

g, CSF biomarker, plasma biomarker
52

Webb, Christina

P52: PET beta-amyloid deposition in h
decreased lure discrimination on a spa

Christina Webb1, Chris Foster1, Marci Horn1, K

1Center for Vital Longevity, The University of Texas a
Individuals with clinically significant beta-amyloid (Α
There has been recent interest, however, in investigati
subclinical Αβ deposition in cognitively normal older
performance in normal aging is typically weak; howev
general memory function. It remains to be determined
hippocampal pattern separation specifically are sensiti
55-98 years associations between Florbetapir uptake a
task that is highly sensitive to hippocampal pattern sep
studied pictures of everyday items in various locations
presented with both studied and new items, as well as
similarity to the studied exemplar. Accurate lure discr
but not exact, to that which was studied. Results of a l
on the slope of lure discrimination across levels of lur
status. Specifically, greater Αβ deposition was associa
the three levels of lure similarity. Older adults with lo
discrimination of old from similar lure items as a func
higher Αβ, however, showed reduced mnemonic discr
suggesting a diminished ability to separate memory re
distinct. Overall, results suggest that even subtle eleva
negatively affects hippocampal pattern separation pro
memory representations.
Keywords: beta-amyloid, preclinical AD, subthreshol

15

healthy older adults is associated with
atial mnemonic similarity task

Kristen Kennedy1, Karen Rodrigue1

at Dallas, 75235, TX, US
Αβ) burden exhibit episodic memory impairment.
ing associations between memory performance and

adults. Overall, the link between Αβ and memory
ver, the majority of studies have utilized measures of
d whether performance on memory tests that tax
ive to Αβ burden. Here we examine in 37 adults aged
and performance on a spatial mnemonic similarity
paration processes. During encoding, participants
s on a computer screen. At retrieval, they were
s similar lure items that varied in the degree of
rimination involved identifying lures as being similar,
linear mixed model showed independent effects of Αβ
re similarity, beyond effects of age or APOE-e4
ated with a reduced slope in lure discrimination across
ower Αβ were better able to modulate accurate
ction of decreasing similarity. Older adults exhibiting
rimination across levels of target-lure similarity,
epresentations even when they become increasingly
ation in Αβ burden in cognitively normal adults
ocesses that support discrimination of highly similar

ld amyloid, pattern separation

53

Ances, Beau

P53: Socioeconomic status mediates ra
T(N) Framework

Julie Wisch1, Darrell Hudson1, Dean Coble1, Ch
Gordon1, Shaney Flores1, Aylin Dincer1, Tamm

1Washington University, St. Louis, MO, US

Background: Previous research shows African Amer
Alzheimer’s disease (AD). Genetic, social (psychoso
increase the risk of AD.

The objectives of this project were to:

1) Assess neuroimaging biomarkers of amyloid (A), ta
differences.

2) Consider mediating effects of socioeconomic status
differences.

Methods: Biomarker measures of neurodegeneration
connectivity (rs-fc)) and amyloid and tau PET data we
Caucasian (n=936) participants enrolled in studies at t
(ADRC). Cardiovascular health (white matter hyperin
index (BMI)) and socioeconomic status (area-level so
index (ADI)) were included in mediation analyses.

Results: Compared to Caucasian participants, African
accumulation but greater neurodegeneration, as measu
global intra-network rs-fc (Figure 1). African America
higher blood pressure, higher BMI, and greater WMH
significantly influenced associations between race and
signature volume, and intra-network rs-fc signature. A
(Figure 3).

Conclusions: Observed racial differences in AD are n
but rather by modifiable factors fueled by differences
SES. Future studies should emphasize collection of re
discrimination, healthcare access, etc.) in addition to t
diversity and inclusion efforts to improve the racial/et
studies.

15

acial differences seen using the A-

hengjie Xiong1, Ganesh Babulal1, Brian
mie Benzinger1, John Morris1, Beau Ances1

ricans are potentially at greater risk for developing
ocial), environmental, and cardiovascular factors may

au (T), and neurodegeneration (N) for potential racial

s and cardiovascular risk factors on observed race

(structural MRI and resting state functional
ere collected from African American (n=169) and
the Knight Alzheimer Disease Research Center
ntensities on MRI, blood pressure, and body mass
ocioeconomic status assessed by the area deprivation

n American participants had lower amyloid PET
ured by decreased cortical volumes and decreased
ans also had lower socioeconomic status (SES),
H volumes. These proposed mediators (Figure 2)
d cortical amyloid PET accumulation, AD cortical
ADI in particular was a significant mediating factor

not primarily due to immutable, genetic differences,
in social context and resources, especially area-level
elevant psychosocial factors (e.g. stress,
the development and implementation of intentional
thnic and socioeconomic representativeness of AD

54

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55

Keywords: PET, fMRI, Race, Health Disparities
15

56

Wolters, Emma

P54: Tau pathology and relative cereb
associated with cognition in Alzheimer

Emma Wolters1,2, Denise Visser1, Sander Verfa
Hayel Tuncel1, Ronald Boellaard1, Albert Wind
van der Flier2,4, Rik Ossenkoppele2,3, Bart van B

1Department of Radiology & Nuclear Medicine, Amst
Amsterdam UMC, Amsterdam, The Netherlands
2Alzheimer Center Amsterdam,, Department of Neuro
Amsterdam, Amsterdam UMC, Amsterdam, The Nethe
3Clinical Memory Research Unit, Lund University, Lu
4Department of Epidemiology and Biostatistics, Vrije
Amsterdam, The Netherlands

Background: We aimed to investigate associations be
(rCBF), and their relationship with cognitive impairm
dynamic [18F]flortaucipir PET scan.

Methods: Seventy-one amyloid positive patients with
underwent a dynamic 130-minute [18F]flortaucipir PE
covering memory, executive functioning, language an
(cerebellar gray matter reference region) was used to c
R1 images, which reflect tau pathology and rCBF, resp
between [18F]flortaucipir BPND and R1and cognition i
and lateral temporal, parietal, occipital and frontal RO

Results: Higher [18F]flortaucipir BPND was associated
occipital regions(table-1). Higher medial temporal BP
temporal, parietal and frontal BPND were associated w
frontal BPND) and attention (except lateral temporal B
lower cognitive scores across all domains (figure-1). F
temporal and parietal ROIs were associated with wors
lower occipital R1 with lower language and attention s
modelled simultaneously, associations between lower
remained, as well as for lower parietal R1 and worse e

Conclusion: Tau pathology and low rCBF were both
performance. For tau pathology, these associations we
independent associations were restricted to lateral tem
functioning and attention domains. These findings su
to cognitive impairment in AD.

15

bral blood flow are independently
r’s disease

aillie1, Emma Coomans1, Tessa Timmers1,2,
dhorst1, Philip Scheltens2, Wiesje van der Flier
Berckel1

terdam Neuroscience, Vrije Universiteit Amsterdam,

ology, Amsterdam Neuroscience, Vrije Universiteit
erlands
und, Sweden
Universiteit Amsterdam, Amsterdam UMC,

etween tau pathology and relative cerebral blood flow
ment in Alzheimer’s disease (AD) using a single

h MCI/dementia (66±8 years, MMSE 23±4)
ET scan and extensive neuropsychological assessment
nd attention domains. Receptor parametric mapping
create non-displaceable binding potential (BPND) and
pectively. We performed linear regression analyses
in the following regions-of-interest (ROIs); medial
OIs.

d with lower R1 in the lateral temporal, parietal and
PND was associated with worse memory. Higher lateral
with worse executive functioning, language (except
BPND). Higher occipital BPND was associated with
For [18F]flortaucipir R1, lower values in the lateral
se executive functioning, language and attention, and
scores. When [18F]flortaucipir BPND and R1 were
r R1 in the lateral temporal and worse attention
executive functioning and attention (table-2).

independently associated with worse cognitive
ere found across the neocortex, while for rCBF
mporal and parietal regions and the executive
uggest that both biomarkers independently contribute

57

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58

Keywords: Tau, cerebral blood flow, PET, Alzheimer’
15

’s disease, cognition
59

Zammit, Matt

P55: Amyloid Load trajectories and ch
amyloid accumulators in Down syndro

Matt Zammit1, Rebecca Koscik1, Charles Laym
Cohen2, Davneet Minhas2, Sterling Johnson1, Sh
Klunk2, Benjamin Handen2, Bradley Christian1

1University of Wisconsin-Madison, Madison, WI, US
2University of Pittsburgh, Pittsburgh, PA, US
3University of Cambridge, Cambridge, UK

Background: Adults with Down syndrome (DS) are a
general population, with a sharp increase in prevalenc
measure of Aβ chronicity (estimated time to Aβ(+) on
(Koscik et al. 2019, in review).

Methods: N=169 DS adults underwent [C-11]PiB sca
evaluation to date (3.0±0.7 scans; 2.4±0.6 years apart)
minute SUVr images were created using cerebellar gr
index (AβL) was calculated from the SUVr images to d
modeling (GBTM) was applied across the AβL data to
(considering linear, quadratic, and cubic polynomials)
solved to determine the estimated age of Aβ(+) onset
by taking the difference between the estimated Aβ(+)

Results: GBTM identified two functions characterizin
non-demented DS sample (Figure 1). 93% of participa
7% to the earlier onset group. The estimated age of Aβ
were 32.6 and 50.4 years, respectively. Aβ chronicity
p<0.0001) with a quadratic model (R2=0.85) indicatin
Discussion: These findings illustrate the utility of Aβ
may be useful to compare the time course of AD biom
this longitudinal study continues, additional Aβ scans

16

hronicity reveal groups of early
ome

mon2, Tobey Betthauser1, Dana Tudorascu2, Ann
hahid Zaman3, Chester Mathis2, William

at increased risk to develop AD compared to the
ce after age 50. By modeling longitudinal Aβ, a
nset) can be useful to investigate preclinical AD

ans. A subset (n=68) underwent longitudinal
). In total, 301 PiB images were obtained. 50-70
ray matter as a reference region. The Amyloid Load
determine global Aβ burden. Group-based trajectory
o identify different patterns of Aβ accumulation
). The trajectories obtained from the model were
(AβL cutoff: 21.5%). Aβ chronicity was determined
age and the chronological age for each participant.
ng age-related Aβ accumulation patterns in our mostly
ants were assigned to the later Aβ(+) onset group and
β(+) for the earlier and later accumulating functions
and AβL were highly correlated (Pearson’s r=0.85,
ng the best fit between these parameters (Figure 2).
chronicity to estimate the time to Aβ(+) onset that
markers between DS and the general population. As
will be included to inform the model.

60

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61

Keywords: Down syndrome, Amyloid Load, Amyloid C
16

Chronicity
62

Ziontz, Jacob

P56: Hippocampal-retrosplenial corte
accumulation in cognitively normal ol

Jacob Ziontz1, Jenna Adams1, Suzanne Baker2, W

1Helen Wills Neuroscience Institute, University of Cal
2Lawrence Berkeley National Laboratory, Berkeley, C

Introduction: Tau is thought to spread transneuronall
parietal lobe (MPL) in cognitively normal older adults
pathology originates. We hypothesize that tau spreads
Methods: Ninety-seven cognitively normal older adu
years) received tau-PET with 18F-Flortaucipir, Ab-PE
unilateral resting state functional connectivity (FC) be
connectivity with the MTL, and hippocampus (HC), a
posteromedial entorhinal cortex (pmEC). We then use
strength (b-weight) between RsC and each MTL subre
tau accumulation (SUVR>1.4) in RsC, precuneus, and
Results: Semipartial correlations revealed RsC FC wi
hemisphere [b=0.40, p<0.001], but not with alEC or p
age, sex, and amyloid status, strength of connectivity
suprathreshold voxels for tau accumulation in the RsC
(Figure 2), precuneus [Left: b=0.18, p=0.001; Right: b
b=0.12, p=0.04; Right: b=0.14, p=0.03]. Proportion of
alEC or RsC-pmEC connectivity in any MPL region.
Discussion: We show that in cognitively normal older
not alEC or pmEC. Further, only RsC-HC connectivit
indicating that tau pathology may spread transneurona
studies should investigate the role of amyloid in this p

16

ex connectivity predicts tau
lder adults

William Jagust1,2

lifornia, Berkeley, Berkeley, CA, US
CA, US
ly from medial temporal lobe (MTL) to medial
s, but it is not known from which region(s) the
s to the MPL via connectivity with the hippocampus.
ults from the Berkeley Aging Cohort Study (76.4±6.1
ET with 11C-PiB, and resting state fMRI. We assessed
etween retrosplenial cortex (RsC), an area of known
anterolateral entorhinal cortex (alEC), and
ed linear models to examine the association of FC
egion with the proportion of suprathreshold voxels for
d posterior cingulate cortex.
ith HC in the left [b=0.33, p<0.001] and right
pmEC in either hemisphere (Figure 1). Adjusting for
between RsC and HC predicted proportion of
C [Left: b=0.11, p=0.06; Right: b=0.18, p=0.003]
b=0.20, p=0.001], and posterior cingulate cortex [Left:
f suprathreshold voxels was not associated with RsC-

r adults, RsC exhibits FC with the hippocampus but
ty predicts tau accumulation in MPL structures,
ally from the MTL through the hippocampus. Future
process as well as associated cognitive changes.

63

Keywords: Tau, connectivity, hippocampus, cognitive
16

ely normal
64

Wednesday, January 15, 2020 - 1:45pm - 2:45pm

SESSION 1: TECHNICA

Wednesday, Ja

01:45 pm SESSION 1:
- 02:45 TECHNICAL I

1:45 PM Evaluation of 18F-JNJ-067 as a tau tracer

2:00 PM A direct comparison of tau imaging agent
2:15 PM 1451 AND [F-18]MK-6240 in human sub
2:30 PM
A multi-center comparison of [18F]flortau
[18F]RO948 and [18F]MK6240 tau-PET
detect optimal target ROIs for differential

Capturing extra-cerebral MK-6240 signal
surface projections

2:45 PM Discussion

16

AL I

anuary 15, 2020

Brad Christian, PhD, University of
Wisconsin-Madison
Ansel Hillmer, PhD, Yale University

r Suzanne Baker, PhD, Lawrence
Berkeley National Laboratory

ts [F-18]AV- Brian Lopresti, MS, University of

bjects Pittsburgh

ucipir, Rik Ossenkoppele, PhD, VU University
tracers to Medical Center
l diagnosis

l with Justin Sanchez, BA,
Massachusetts General Hospital

65

Baker, Suzanne

Evaluation of 18F-JNJ-067 as a tau tra

Suzanne Baker1, Karine Provost2, Wesley Thom
Schmidt4, Maarten Timmers4, Hartmuth Kolb5,

1Lawrence Berkeley National Laboratory, Berkeley, C
2University of California, San Francisco, San Francis
3University of California, Berkeley, Berkeley, CA, US
4Janssen Research and Development of Janssen Phar
5Neuroscience Biomarker Research of Janssen Resear

Introduction: Current tau PET tracers have obvious s
binds to aggregated tau in AD brain tissue with Ki=2.
individuals with AD (N=3), MCI (N=3), PSP (N=2) a

Methods: Following PIB and MRI scans, 11 subjects
18F-JNJ-067 injection on a Siemens Biograph PET/CT
FreeSurfer ROIs. Time activity and SUVR curves and
pharmacokinetics.

Results: Subject ages ranged from 72-92. All AD and
from 18-30. All PSP and HCs were PIB negative. Ste
tracer retention within 90 minutes (Figure 1). Figure 2
k2ref=0.05min-1 derived from SRTM) was 0.73-1.88 an
binding was seen in the basal ganglia and thalamus an
Entorhinal cortex showed low binding in HCs, PSPs a
was indistinguishable from HCs, one showed very low
temporal lobe. All ADs showed high cortical binding,
(MCI/AD only r2=0.65; all subjects r2=0.74).

Conclusion: This tracer shows relatively slow pharma
binding in the basal ganglia and white matter but not e
MCIs. Binding in AD patients reflects a typical patter
patients are intermediate. These data suggest that 18F-
continuum.

16

acer

mas3, AJ Whitman3, Mustafa Janabi1, Mark
Gil Rabinovici2, William Jagust1,3

CA, US
sco, CA, US
S
rmaceutical, Beerse, Belgium
rch and Development, La Jolla, CA, US
shortcomings. 18F-JNJ-067 is a new tau tracer that
.4nM. Our objective was to evaluate 18F-JNJ-067 in
and healthy controls (HC, N=3).
s (see Figure 3) underwent 90 min dynamic scans after
T. Data were analyzed in native space with
d DVR were used to evaluate the tracer binding and

d MCI subjects were PIB positive with MMSE scores
eady state was not reached in ROIs with high levels of
2 shows the dynamic range for DVR (30-90,
nd figure 3 shows DVR images. Across all subjects
nd not appreciably higher in PSPs than HCs.
and MCIs. MCIs showed low cortical binding, one
w binding and one showed focal binding in the right
, and MMSE and DVR in a meta-ROI were correlated

acokinetics with low levels of probable off-target
elsewhere, and low entorhinal signal in HCs and
rn of tau distribution seen with other tracers, and MCI
-JNJ-067 is suitable for investigation of the AD

66

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67

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68

Keywords: 18F-JN-067 tau PET tracer
16

69

Lopresti, Brian

A direct comparison of tau imaging ag
6240 in human subjects

Brian Lopresti1, Davneet Minhas1, Alexandra G
Scott Mason1, Chester Mathis1, William Klunk2

1Department of Radiology, University of Pittsburgh Sc
2Department of Psychiatry, University of Pittsburgh S

Background: Tau PET imaging agents exhibit varyin
binding patterns. This study compares the imaging pr
[18F]AV-1451 and [18F]MK-6240, in the same subject
Methods:[18F]AV-1451 and [18F]MK-6240 scans wer
< 2 months apart, who varied in terms of clinical diag
30). FreeSurfer v5.3 was used to define regions-of-int
pathologic stages (I-VI). Off-target binding was asses
SUVR outcomes were determined over 80-100 min ([
injection normalized to cerebellar grey matter. Blinde
performed by three expert readers, who scored each B
negative (0) to definitely positive (3).
Results: Although the outcomes were highly correlate
(hippocampus, r2=0.52), the dynamic range of SUVR
[18F]MK-6240 than [18F]AV-1451 (see figure). Cereb
[18F]AV-1451 (0.84±0.16 vs 0.88±0.19, respectively),
driven by specific signal. Off-target binding in striatu
observed with [18F]AV-1451, whereas off-target bindi
of 9/15 subjects. Visual reads were highly concordan
Conclusion: Both [18F]MK-6240 and [18F]AV-1451
tau deposits. [18F]MK-6240 showed increased dynami
choroid plexus, but this resulted in no clear difference

17

gents [F-18]AV-1451 AND [F-18]MK-

Gogola1, Charles Laymon1, Ann Cohen2, N.

2

chool of Medicine, Pittsburgh, PA, US
School of Medicine, Pittsburgh, PA, US
ng levels of specific signal and distinct off-target
roperties of two frequently used tau imaging agents,
ts.
re collected in 15 elderly subjects (6M, 9F, age 74±8)
gnosis (5 AD, 1 MCI, 9 NC) and cognition (MMSE 9-
terest (3T MPRAGE) corresponding to Braak
ssed in choroid plexus and a composite striatal region.
[18F]AV-1451) or 70-90 min ([18F]MK-6240) post-
ed consensus visual interpretation of all images was
Braak region on a 4-point scale ranging from definitely

ed (r2>0.91) for all Braak regions except Braak II
values in target regions was ~2 fold higher for
bellar SUVs were similar for [18F]MK-6240 and
, suggesting that differences in SUVR values are
um (STR) and choroid plexus was frequently
ing of [18F]MK-6240 was observed in the meninges
nt in 13/15 subjects.
are capable of visualizing a spectrum of pathologic
ic range and lower off-target binding in striatum and
e in the visual interpretation of PET scans.

70

Keywords: tau PET AV-1451 MK-6240
17

71

Ossenkoppele, Rik

A multi-center comparison of [18F]flo
[18F]MK6240 tau-PET tracers to dete
differential diagnosis

Antoine Leuzy1, Rik Ossenkoppele1,2, Ruben Sm
Tharick Pascoal5, Andréa Benedet5,6, Hannah C
Rabinovici8, Pedro Rosa-Neto5,9,10, Oskar Hanss

1Clinical Memory Research Unit, Department of Clini
2VU University Medical Center, Neuroscience Campu
3Department of Neurology, Skåne University Hospital
4Wallenberg Centre for Molecular Medicine, Lund Un
5Translational Neuroimaging Laboratory, McGill Cen
Montreal, QC, Canada
6CAPES Foundation, Ministry of Education of Brazil,
7Department of Neurology, Gangnam Severance Hosp
Korea
8Department of Neurology, University of California S
Francisco, CA, US
9Montreal Neurological Institute, Montreal, QC, Cana
10Department of Neurology and Neurosurgery, McGil
11Memory Clinic, Skåne University Hospital, Lund, Sw

Objectives: To examine whether similar target-ROIs
[18F]RO948 and [18F]MK6240 tau-PET tracers to diff
(CU) controls and ii) cases with non-AD neurodegene

Methods: Tau-PET data was collected across six-coh
[US]; UCSF [US], Gangnam Severance Hospital [Sou
Future analyses will also be performed with [18F]MK6
follows: for [18F]flortaucipir, 179 AD dementia, 42 Aβ
dementia, 201 Aβ-CU and 107 non-AD. Aβ-status wa
amyloid-PET, as available. SUVR values (inferior cer
ROIs ([18F]flortaucipir, 80-100 min; [18F]RO948 70-9
ROC curve [AUC] for AD dementia vs CU and non-A
(entorhinal cortex), I-IV (meta-temporal ROI), V-VI (
2016], and an early-Tau ROI [entorhinal cortex, inferi
data-driven target-ROIs (optimal classifiers were cons
selection operator [LASSO]). Cut-points were determ
CU).

Results: LASSO based ROIs are shown for [18F]florta
performance across ROIs and cut-points are shown in
performance (AUC) of the optimized LASSO-based R
for Braak I-IV/early-Tau regions. For [18F]RO948, the
VI/early-Tau ROIs, but not to Braak I-II and I-IV.

Conclusions: A common-ROI encompassing parts of
differential diagnosis with both [18F]flortaucipir and [
point of around 1.35 SUVR. Additional analyses will
[18F]MK6240.

17

ortaucipir, [18F]RO948 and
ect optimal target ROIs for

mith1,3, Philip Insel1, Niklas Mattsson1,3,4,
Cho7, Chul H. Lyoo7, Renaud La Joie8, Gil

son1,11

ical Sciences, Malmö, Sweden
us Amsterdam, Amsterdam, The Netherlands
l, Lund, Sweden
niversity, Lund, Sweden
ntre for Studies in Aging, McGill University,

, Brasília, BR
pital, Yonsei University College of Medicine, Seoul,

San Francisco, Memory and Aging Center, San

ada
ll University, Montreal, QC, Canada
weden

and cut-points can be used across [18F]flortaucipir,
ferentiate AD dementia from i) cognitively unimpaired
erative disorders.

horts: ([18F]flortaucipir, BioFINDER [Sweden], ADNI
uth Korea]; [18F]RO948, BioFINDER-2 [Sweden]).
6240 (TRIAD, Canada). Diagnostic-groups were as
β-CU and 247 non-AD; for [18F]RO948, 117 AD
as determined using CSF (Aβ42, Aβ42/Aβ40) or
rebellar reference) were calculated across FreeSurfer-
90 min). Diagnostic performance (area-under-the-
AD) was assessed across predefined (Braak I-II
(widespread neocortical areas) [Cho et al. Neurology
ior temporal, parahippocampus/fusiform-gyrus]) and
structed using the least absolute shrinkage and
mined using the Youden-index (AD dementia vs Aβ-

aucipir and [18F]RO948 in Figures 1 and 2. Diagnostic
n Table 1. For [18F]flortaucipir, the diagnostic
ROIs was superior to that for Braak I-II/V-VI, but not
e LASSO based ROIs were superior to the Braak V-

the temporal lobe (i.e. Braak I-IV) can be used for
[18F]RO948 tau-PET, and that using very similar cut-
address whether this also holds true for

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73

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74

Keywords: Tau, PET, Flortaucipir, RO948, MK6240
17

75

Sanchez, Justin

Capturing extra-cerebral MK-6240 sig

Justin Sanchez1, Alex Becker1, Zoe Rubinstein1
Price1, Keith Johnson1,2

1Massachusetts General Hospital, Boston, MA, US
2Brigham and Women’s Hospital, Boston, MA, US

Introduction: MK-6240 is a high-affinity tau PET lig
background cortical signal in high-binding cases, as w
the subarachnoid space, including meninges, which ca
cortical ribbon. We assessed whether surface projectio
cortical and extra-cerebral MK-6240 signal.
Methods: FreeSurfer surface projections of MK-6240
generated across various projection fractions (PF) to s
grey matter midpoint (PF=0.5), pial surface boundary
gyri SUVrs were computed to assess the effect of vary
low-aβ clinically normal subjects (age 37-82, 64.7±11
various PF was assessed in one subject with visually h
Results: Surface projection data were consistent with
with high cortical binding, SUVrs were highest inside
(Fig.1A), while in cases with low cortical and high ex
brain (PF=2.0, Fig.1B). In the low-aβ group, SUVr di
frontal and lateral regions, and smaller in midline stru
(insula, transverse temporal) (Fig.2). In dynamic data,
in early frames (0-40min), while extra-cerebral signal
(Fig.3).
Conclusions: Surface projections of MK-6240 using
signal while preserving cortical ribbon signal. Cortica
trajectories over time post-injection, suggesting that e
for using projections of dynamic MK-6240 data.

17