Journal of neuroimaging : official journal of the American Society of Neuroimaging
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Comparative Study
Comparative reliability of total intracranial volume estimation methods and the influence of atrophy in a longitudinal semantic dementia cohort.
Total intracranial volume (TIV) as a measure of premorbid brain size is often used to correct volumes of interest for interindividual differences in magnetic resonance imaging (MRI) studies. We directly compared the reliability of different TIV estimation methods to address whether such methods are influenced by brain atrophy in the neurodegenerative disease, semantic dementia. ⋯ The mid-cranial sampling of PD images achieved the best combination of precision, reliability, and user-friendliness. SPM5 is an attractive alternative if the highest level of precision is not required.
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Despite denial as a disease entity, carotidynia had shown relatively concordant imaging finding as an inflammatory process surrounding the carotid bifurcation area. We report serial computed tomography (CT) images of a case with carotidynia that showed the layered thickening of the carotid wall with self-limiting disease course.
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We studied an auditory continuous performance task with positron emission tomography(PET) and EEG-derived current density reconstructions (CDRs) to define the spatial and temporal aspects of auditory attention. ⋯ The cingulate may play an important role in post-decisional activity and control activity at other sites involved in post-decisional cognitive processing.
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Hypertensive encephalopathy typically presents with headache and confusion and bilateral parietooccipital vasogenic edema. Brain stem and cerebellar edema in hypertensive encephalopathy usually occurs in association with these typical supratentorial changes and is usually asymptomatic. ⋯ Rapid treatment of hypertension resulted in clinical and radiological improvement. Prompt recognition of the cause and aggressive treatment of hypertension in such patients are crucial to relieve edema and prevent life-threatening progression.
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Ischemic stroke is mainly caused by embolism. Vascular emboli can be solid or gaseous and can be non-invasively registered by transcranial Doppler ultrasound as microembolic signals (MESs). The existing methods are limited as they do not distinguish between cases in which a single embolus is present and those in which multiple emboli -- perhaps a mix of those gaseous and solid in nature -- are present. In a previous in vitro study, we have developed a wavelet-based algorithm to detect multiple emboli. We proceed with this technique to investigate whether it could prove useful in patients. ⋯ Multiple emboli were detected and quantified in patients using continuous wavelet transform. These were difficult to observe using conventional analysis techniques.