Absolute volume flow rate (VFR) for cut-planes placed of static phantom in Fig 1.

<p>As each cut-plane was placed in stationary background, a VFR of zero (ml/s)/pixel was expected in the measurements. A larger reduction in VFR estimates indicates better calibration performance.</p

Absolute VFR reduction as a percentage of the uncorrected VFR for each of the three correction schemes: local bias correction (LBC), local polynomial correction (LPC), whole brain polynomial correction (WBPC) for cut-planes placed in background tissue as describe in Table 1.

<p>Group (by cut-plane orientation, defined in <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0149930#pone.0149930.g002" target="_blank">Fig 2</a>) and overall mean and standard deviation are provided. A larger absolute VFR reduction indicates better calibration performance in stationary tissue.</p

Correlation (left column) and Bland-Altman (right column) plots.

<p>Each row shows the results for a different correction scheme. A strong correlation was observed with each correction method. The Bland-Altman graphs plot the mean difference and two standard deviations of the difference. The average of the differences for LBC, LPC, and WBPC methods were found to be -0.036 ± 0.048 ml/s (mean ± standard deviation), 0.088 ± 0.155 ml/s, and -0.017 ± 0.059 ml/s, respectively.</p

Velocity measurements and whole polynomial fit in an axial slice of a static phantom.

<p>The top row shows the measured velocity in the phantom and the bottom row shows the whole brain polynomial fit. Measurements corresponding to these images can be found in <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0149930#pone.0149930.t001" target="_blank">Table 1</a>.</p

Absolute volume flow rate (VFR) for cut-planes placed in background tissue.

<p>These numbers represent the absolute measured VFR before and after correction. Measurements for each location and orientation are averaged over the thirty subjects. Population mean and standard deviation are provided. As each cut-plane was placed in stationary background tissue, a VFR of zero (ml/s)/pixel was expected in the measurements. A larger reduction in VFR estimates indicates better calibration performance.</p

Correction performance in background tissue measurements for a single location (Inferior-Anterior-Left).

<p>The columns represent different cut-plane orientations and the rows correspond to the different correction methods. The open circles represent the uncorrected measurements and the symbols represent the results after applying the three correction techniques. The solid black lines show the average correction and the dashed lines represent the average uncorrected measurements versus subject. With all orientations and methods the corrected mean measurements in stationary tissue were closer to zero (ml/s)/pixel.</p

Table_1_Subcortical volumes in cerebral amyloid angiopathy compared with Alzheimer’s disease and controls.docx

BackgroundPrevious reports have suggested that patients with cerebral amyloid angiopathy (CAA) may harbor smaller white matter, basal ganglia, and cerebellar volumes compared to age-matched healthy controls (HC) or patients with Alzheimer’s disease (AD). We investigated whether CAA is associated with subcortical atrophy.MethodsThe study was based on the multi-site Functional Assessment of Vascular Reactivity cohort and included 78 probable CAA (diagnosed according to the Boston criteria v2.0), 33 AD, and 70 HC. Cerebral and cerebellar volumes were extracted from brain 3D T1-weighted MRI using FreeSurfer (v6.0). Subcortical volumes, including total white matter, thalamus, basal ganglia, and cerebellum were reported as proportion (%) of estimated total intracranial volume. White matter integrity was quantified by the peak width of skeletonized mean diffusivity.ResultsParticipants in the CAA group were older (74.0 ± 7.0, female 44%) than the AD (69.7 ± 7.5, female 42%) and HC (68.8 ± 7.8, female 69%) groups. CAA participants had the highest white matter hyperintensity volume and worse white matter integrity of the three groups. After adjusting for age, sex, and study site, CAA participants had smaller putamen volumes (mean differences, −0.024% of intracranial volume; 95% confidence intervals, −0.041% to −0.006%; p = 0.005) than the HCs but not AD participants (−0.003%; −0.024 to 0.018%; p = 0.94). Other subcortical volumes including subcortical white matter, thalamus, caudate, globus pallidus, cerebellar cortex or cerebellar white matter were comparable between all three groups.ConclusionIn contrast to prior studies, we did not find substantial atrophy of subcortical volumes in CAA compared to AD or HCs, except for the putamen. Differences between studies may reflect heterogeneity in CAA presenting syndromes or severity.</p

Table_1_The relationship of small vessel disease burden on cerebral and regional brain atrophy rates and cognitive performance over one year of follow-up after transient ischemic attack.DOCX

BackgroundStroke, even when minor, increases the risk of dementia. We aimed to determine whether patients with transient ischaemic attack (TIA) exhibit higher rates of cerebral and regional atrophy 1-year after first stroke symptoms and evaluate the relationship with small vessel disease and cognitive performance.MethodsTIA patients and controls without cognitive symptoms underwent high-resolution T1-weighted MRI and cognitive testing at baseline and 1-year. Percent brain volume change (PBVC) was measured, and the location of regional atrophy and small vessel disease (CSVD) burden was evaluated. Neuropsychological testing assessed memory, processing speed, and executive function.ResultsA total of 76 TIA patients and 53 controls of mean age 67 (SD = 8) and 68 years (SD = 8) were recruited. TIA patients demonstrated greater improvement of visual memory and executive function at 1-year. TIA patients had greater median PBVC/year compared to controls (−0.79% [(−1.22)-(−0.38)] vs. -0.41% [(−0.62)-0.19]; p ConclusionA near two-fold increase in rate of cerebral atrophy 1-year after TIA is associated with higher SBP emphasizing the need for improved treatment of SBP. Cerebral and regional atrophy rates may be used to select patients for vascular risk reduction trials or novel therapeutics in future dementia prevention trials.</p