AJNR. American journal of neuroradiology
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AJNR Am J Neuroradiol · Sep 2016
Association of Automatically Quantified Total Blood Volume after Aneurysmal Subarachnoid Hemorrhage with Delayed Cerebral Ischemia.
The total amount of extravasated blood after aneurysmal subarachnoid hemorrhage, assessed with semiquantitative methods such as the modified Fisher and Hijdra scales, is known to be a predictor of delayed cerebral ischemia. However, prediction rates of delayed cerebral ischemia are moderate, which may be caused by the rough and observer-dependent blood volume estimation used in the prediction models. We therefore assessed the association between automatically quantified total blood volume on NCCT and delayed cerebral ischemia. ⋯ A higher total blood volume measured with our automated quantification method is significantly associated with delayed cerebral ischemia. The results of this study encourage the use of rater-independent quantification methods in future multicenter studies on delayed cerebral ischemia prevention and prediction.
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AJNR Am J Neuroradiol · Sep 2016
Tractography at 3T MRI of Corpus Callosum Tracts Crossing White Matter Hyperintensities.
The impact of white matter hyperintensities on the diffusion characteristics of crossing tracts is unclear. This study used quantitative tractography at 3T MR imaging to compare, in the same individuals, the diffusion characteristics of corpus callosum tracts that crossed white matter hyperintensities with the diffusion characteristics of corpus callosum tracts that did not pass through white matter hyperintensities. ⋯ In the corpus callosum and cingulum, tracts had worse diffusion characteristics when they crossed white matter hyperintensities. These results support a role for white matter hyperintensities in the disruption of crossing tracts.
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AJNR Am J Neuroradiol · Sep 2016
Centripetal Propagation of Vasoconstriction at the Time of Headache Resolution in Patients with Reversible Cerebral Vasoconstriction Syndrome.
Reversible cerebral vasoconstriction syndrome is characterized by thunderclap headache and diffuse segmental vasoconstriction that resolves spontaneously within 3 months. Previous reports have proposed that vasoconstriction first involves small distal arteries and then progresses toward major vessels at the time of thunderclap headache remission. The purpose of this study was to confirm centripetal propagation of vasoconstriction on MRA at the time of thunderclap headache remission compared with MRA at the time of reversible cerebral vasoconstriction syndrome onset. ⋯ This study found evidence of centripetal propagation of vasoconstriction on MRA obtained at the time of thunderclap headache remission, compared with MRA obtained at the time of reversible cerebral vasoconstriction syndrome onset. If clinicians remain unsure of the diagnosis during early-stage reversible cerebral vasoconstriction syndrome, this time point represents the best opportunity to diagnose reversible cerebral vasoconstriction syndrome with confidence.
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AJNR Am J Neuroradiol · Aug 2016
Multicenter StudyGeometric Parameter Analysis of Ruptured and Unruptured Aneurysms in Patients with Symmetric Bilateral Intracranial Aneurysms: A Multicenter CT Angiography Study.
Previous studies of geometric and morphologic parameters of intracranial aneurysms have been conducted to determine rupture risk, which remains incompletely defined due to patient-specific risk factors, such as sex, hypertension, and age. To this end, we compared characteristics of ruptured and unruptured aneurysms in the same patients with symmetric bilateral intracranial aneurysms. ⋯ An aspect ratio of ≥1.6, area ratio of ≥1.5, and irregular wall are associated with aneurysm rupture independent of aneurysm size and patient characteristics. These characteristics alone can help in distinguishing ruptured bilateral intracranial aneurysms from unruptured ones.
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AJNR Am J Neuroradiol · Aug 2016
A Diffusion Tensor Imaging Study on White Matter Abnormalities in Patients with Type 2 Diabetes Using Tract-Based Spatial Statistics.
Patients with type 2 diabetes mellitus have considerably higher risk of developing cognitive impairment and dementia. WM changes in these patients have been reported. Our aim was to demonstrate that gradual and continuous WM change and the associated cognitive decline in patients with type 2 diabetes mellitus can be captured by DTI parameters, which can be used to complement neuropsychological test scores in identifying patients with type 2 diabetes mellitus with and without mild cognitive impairment. ⋯ DTI parameters can show a substantial difference between patients with type 2 diabetes mellitus with and without mild cognitive impairment, suggesting their potential use as an imaging marker for detecting cognitive decline in patients with type 2 diabetes mellitus. More important, DTI parameters may capture gradual and continuous WM changes that can be associated with early stages of cognitive decline in patients with type 2 diabetes mellitus before they can be diagnosed clinically by using conventional neuropsychological tests.