Developing Topics.

Background: Cerebral small vessel disease (CSVD) is common in Alzheimer's disease (AD), but it is unclear how CSVD affects cognition and disease progression. Peak width of Skeletonized Mean Diffusivity (PSMD) is a Magnetic Resonance Imaging (MRI) marker of global white matter integrity, believed to reflect both total vascular burden and the cognitive impact of CSVD. We examined the relationship between PSMD and memory, processing speed and executive function, and to assess the predictive value of PSMD on clinical progression.

Plasma brain-derived tau is an amyloid-associated neurodegeneration biomarker in Alzheimer's disease.

Staging amyloid-beta (Aβ) pathophysiology according to the intensity of neurodegeneration could identify individuals at risk for cognitive decline in Alzheimer's disease (AD). In blood, phosphorylated tau (p-tau) associates with Aβ pathophysiology but an AD-type neurodegeneration biomarker has been lacking. In this multicenter study (n = 1076), we show that brain-derived tau (BD-tau) in blood increases according to concomitant Aβ ("A") and neurodegeneration ("N") abnormalities (determined using cerebrospinal fluid biomarkers); We used blood-based A/N biomarkers to profile the participants in this study; individuals with blood-based p-tau+/BD-tau+ profiles had the fastest cognitive decline and atrophy rates, irrespective of the baseline cognitive status.

Medial Temporal Lobe Atrophy in Predementia Alzheimer's Disease: A Longitudinal Multi-Site Study Comparing Staging and A/T/N in a Clinical Research Cohort.

Background: Atrophy of the medial temporal lobe (MTL) is a biological characteristic of Alzheimer's disease (AD) and can be measured by segmentation of magnetic resonance images (MRI).

Objective: To assess the clinical utility of automated volumetry in a cognitively well-defined and biomarker-classified multi-center longitudinal predementia cohort.

Methods: We used Automatic Segmentation of Hippocampal Subfields (ASHS) to determine MTL morphometry from MRI.

Brain amyloid and vascular risk are related to distinct white matter hyperintensity patterns.

White matter hyperintensities (WMHs) are associated with vascular risk and Alzheimer's disease. In this study, we examined relations between WMH load and distribution, amyloid pathology and vascular risk in 339 controls and cases with either subjective (SCD) or mild cognitive impairment (MCI). Regional deep (DWMH) and periventricular (PWMH) WMH loads were determined using an automated algorithm.

Detecting At-Risk Alzheimer's Disease Cases.

While APOEɛ4 is the major genetic risk factor for Alzheimer's disease (AD), amyloid dysmetabolism is an initial or early event predicting clinical disease and is an important focus for secondary intervention trials. To improve identification of cases with increased AD risk, we evaluated recruitment procedures using pathological CSF concentrations of Aβ42 (pAβ) and APOEɛ4 as risk markers in a multi-center study in Norway. In total, 490 subjects aged 40-80 y were included after response to advertisements and media coverage or memory clinics referrals.

Loss of opposite left ventricular basal and apical rotation predicts acute response to cardiac resynchronization therapy and is associated with long-term reversed remodeling.

Background: Normal left ventricular (LV) torsion is caused by opposite basal and apical rotation. Opposite rotation can be lost in heart failure, but might be restored by pacing; therefore, the predictive value of the loss of opposite base-apex rotation in heart failure patients for the response to cardiac resynchronization therapy (CRT) was studied.

Methods And Results: In 34 CRT candidates and 12 controls, basal and apical LV rotations were calculated using magnetic resonance image tagging.

Comparison of 2D and 3D calculation of left ventricular torsion as circumferential-longitudinal shear angle using cardiovascular magnetic resonance tagging.

Purpose: To compare left ventricular (LV) torsion represented as the circumferential-longitudinal (CL) shear angle between 2D and 3D quantification, using cardiovascular magnetic resonance (CMR).

Methods: CMR tagging was performed in six healthy volunteers. From this, LV torsion was calculated using a 2D and a 3D method.

Quantitative comparison of 2D and 3D circumferential strain using MRI tagging in normal and LBBB hearts.

The response to cardiac resynchronization therapy (CRT), which is applied to patients with heart failure (HF) and left bundle-branch block (LBBB), can be predicted from the mechanical dyssynchrony measured on circumferential strain. Circumferential strain can be assessed by either 2D or 3D strain analysis. In this study was evaluated the difference between 2D and 3D circumferential strain using MR tagging with high temporal resolution (14 ms).

Extended harmonic phase tracking of myocardial motion: improved coverage of myocardium and its effect on strain results.

Purpose: To extend the harmonic phase (HARP) tracking method in order to track the myocardial tissue that appears near the epicardial contour during systole and reappears near the endocardial contour during diastole, due to the longitudinal motion and conical shape of the heart.

Materials And Methods: A mathematical model of myocardial deformation was used to quantify the accuracy of the extended HARP tracking and of the strain computation. For six healthy volunteers, the number of tracked points and the two-dimensional strain components were computed with the extended and with the original HARP tracking version.