MTL SUBREGIONAL MORPHOMETRY USING HIGH RESOLUTION MRI IN ADNI2

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Poster Presentations: P3

were improved at 3 days after treatment of delirium, and all of symptoms, except retardation, were more improved at 7 days after treatment of delirium. Conclusions: There are few studies for short-term outcome of delirium in elderly. Sixty-seven percentages in elderly patients with delirium are improved in 7 days after atypical antipsychotics. Almost all symptoms of delirium were improved at 3 days after atypical antipsychotics. However, the symptoms of Delusion and Retardation are remained.

hippocampal subfields CA and DG, with CA1 showing the strongest group separation (see figure). Table 1 Group comparisons of subregional measurements between OHC and eMCI (column 2) and lMCI (column 3) respectively. T-statistic from two sample t-test is shown. Columns 4 and 5 show correlation of subregional measurements with pTau and Ab respectively. p-values are given in parentheses. Subregional OHC>eMCI OHC>lMCI measurement t-statistic(p) t-statistic(p)

P3-184

MTL SUBREGIONAL MORPHOMETRY USING HIGH RESOLUTION MRI IN ADNI2 1

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Sandhitsu Das , John Pluta , Paul Yushkevich , David A. Wolk , 1 University of Pennsylvania, Philadelphia, Pennsylvania, United States; 2 University of Pennsylvania, Philadelphia, Pennsylvania, United States. Contact e-mail: [email protected] Background: We present the first group analysis of fully automated medial temporal lobe (MTL) subregional measurements using the newly available high-resolution MTL MRI in the ADNI2 dataset. We have been developing an automated method to quantify hippocampal subfields and extra-hippocampal MTL cortices from high-resolution (0.4x0.4mm in-plane) T2-MRI tailored for MTL imaging that was recently included in the ADNI2 acquisition protocol. This method is one of several being tested by the ADNI2 subfield analysis group. We also present a visualization/morphometric tool to study local thickness differences within the MTL as a way to assess subtle, subregional effects. Methods: Cornu Ammonis (CA1/2/3) and dentate gyrus (DG) subfields of the hippocampal formation, subiculum, and entorhinal (ERC) and perirhinal (PRC) cortices (BA35 and BA36) were automatically labeled in ADNI2 high-resolution MTL MRI (NeuroImage 53:1208-1224, 2010). Volumes of hippocampal subfields and cortical thickness within the extra-hippocampal cortices were compared in 37 older healthy control and 44 MCI subjects - 27 designated as early (eMCI), 17 late (lMCI). Thickness was derived by integrating thickness maps computed from T1-MRI over the labels obtained from high-resolution MRI, and used instead of volume for MTL cortices given greater uncertainty in lateral boundaries of these regions. Additionally, a regional thickness map was constructed from the segmentation masks of CA/SUB/ERC/PRC and analyzed in a common atlas space. We also explored correlation of CSF biomarkers with subregional measurements. Results: Hippocampal subfield volumes as well as thickness in extrahippocampal cortices were significantly reduced in the entire MCI cohort relative to OHC, with CA1 showing the largest group effect. However, when just eMCI was compared to OHC, the only significant difference was found in PRC thickness. Within MCI, PRC thickness (BA35) had the strongest significant positive correlation with CSF pTau, whereas CA1 volume had the strongest significant negative correlation with CSF Ab. Conclusions: Subregional MTL measurements showed significant group effect only in PRC for eMCI patients, consistent with the earliest appearance of pathology in this region (Braak Stage I). With further disease progression in lMCI, significant effects appeared in ERC, SUB as well as

Left CA1 volume Right CA1 volume Left CA2 volume Right CA2 volume Left CA3 volume Right CA3 volume Left DG volume Right DG volume Left SUB volume Right SUB volume Left ERC thickness Right ERC thickness Left BA35 thickness Right BA35 thickness Left BA36 thickness Right BA36 thickness

pTau corr in MCI r(p)

Ab corr in MCI r(p)

1.47 (0.07)

5.6 (9.08e-7) -0.36 (0.01)

0.51 (0.0002)

1.51 (0.07)

4.83 (1.95e-5) -0.34 (0.02)

0.48 (0.0006)

0.26 (0.38)

2.38 (0.01)

-0.21 (0.16)

0.22 (0.12)

0.03 (0.49)

1.45 (0.08)

-0.02 (0.85)

0.10 (0.48)

-0.32 (0.63)

-0.06 (0.52)

0.01 (0.94)

0.13 (0.37)

0.15 (0.44)

-0.16 (0.56)

-0.07 (0.62)

0.05 (0.72)

1.01 (0.16)

4.44 (6.43e-5) -0.27 (0.07)

0.43 (0.002)

1.12 (0.13)

4.84 (1.77e-5) -0.36 (0.01)

0.52 (0.0002)

0.68 (0.25)

4.33 (4.23e-5) -0.34 (0.02)

0.49 (0.0003)

0.96 (0.17)

5.13 (4.06e-6) -0.34 (0.02)

0.45 (0.001)

0.80 (0.21)

2.33 (0.01)

-0.27 (0.06)

0.20 (0.17)

0.89 (0.19)

2.71 (0.006)

-0.32 (0.02)

0.33 (0.02)

1.6 (0.06)

2.60 (0.007)

-0.39 (0.006) 0.28 (0.06)

1.89 (0.03)

2.38 (0.01)

-0.30 (0.04)

0.23 (0.12)

2.87 (0.003)

1.91 (0.03)

-0.29 (0.03)

0.17 (0.22)

2.96 (0.002)

2.19 (0.02)

-0.27 (0.07)

0.15 (0.30)

T-statistic maps of regional thickness difference between older healthy controls and early MCI (left) and late MCI (right).Top row shows a superior view featuring the entire length of the hippocampal formation, bottom row shows a posterior view that highlights the folds of the extrahippocampal cortices.