Journal of neuroimaging : official journal of the American Society of Neuroimaging
-
Susceptibility-Weighted 3T MRI of the Swallow Tail Sign in Multiple Sclerosis: A Case Control Study.
The swallow tail sign describes the physiological appearance of nigrosome-1 within the substantia nigra on high-resolution transverse susceptibility-weighted imaging (SWI). Previous studies demonstrated its absence in Parkinson's disease due to increasing iron content. In multiple sclerosis (MS), increased iron accumulation can be found in the brain tissue including the substantia nigra. ⋯ The finding of an abnormal swallow tail sign in MS patients may provide an additional imaging marker even in early MS development.
-
Blood-derived monocytes/macrophages can be labeled with ultrasmall superparamagnetic iron oxides (USPIO) at periphery and subsequently migrate into areas of inflammation in the brain. We investigated temporal pattern of migration of peripheral immune cells in Theiler's murine encephalomyelitis virus (TMEV) model of chronic demyelination by USPIO-enhanced imaging. ⋯ Serial USPIO imaging is a promising biomarker for investigating the effect of therapeutic interventions on monocytes/macrophages and microglia activation and neurodegeneration in TMEV-infected animals.
-
Cerebrovascular disease is a common comorbidity in older adults, typically assessed in terms of white matter hyperintensities (WMHs) on MRI. While it is well known that WMHs exacerbate cognitive symptoms, the exact relation of WMHs with cognitive performance and other degenerative diseases is unknown. Furthermore, based on location, WMHs are often classified into periventricular and deep WMHs and are believed to have different pathological origins. ⋯ Of note, more associations were detected between cognitive performance and deep WMHs than between cognitive performance and periventricular WMHs. Mechanistically, both deep and periventricular WMHs were associated with increased MD. Both deep and periventricular WMHs were also associated with reduced CBF in the gray matter.
-
The breath-holding index (BHI) is a useful method to assess cerebrovascular reactivity. It is calculated based on the mean flow velocities of the middle cerebral artery (MCA) using transcranial Doppler (BHIMCA ). Therefore, it is not feasible in patients with poor temporal windows. This study tested the feasibility of a BHI using the internal carotid artery (ICA) siphon flow velocity (BHIICA ). ⋯ Our study suggests that the BHIICA is not a feasible alternative method to the BHIMCA.
-
Aneurysm size and neck measurements are important for treatment decisions. The introduction of 7T magnetic resonance angiography (MRA) led to new possibilities assessing aneurysm morphology and flow due to the higher signal-to-noise ratio. However, it is unknown if the size measurements on 7T MRA are similar to those on the standard 3T MRA. This study aimed to compare aneurysm size measurements between 7T and 3T MRA. ⋯ Our study showed that 7T MRA, both nonenhanced and contrast-enhanced, has a high agreement in aneurysm size measurements compared to 3T. This suggests that 7T is useful for reliable aneurysm size assessment.