Journal of neuroimaging : official journal of the American Society of Neuroimaging
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Pontine tegmental cap dysplasia (PTCD) is recently recognized as a rare congenital brain stem malformation with typical neuroimaging hallmarks of ventral pontine hypoplasia and vaulted pontine tegmentum projecting into the fourth ventricle. PTCD patients also demonstrate variable cranial neuropathy with predilection for involvement of the vestibulocochlear and facial nerves. ⋯ During early infancy, the patient displayed features of multiple cranial neuropathies and bilateral hearing loss. At the age of 2, the patient underwent further MRI assessment with dedicated high resolution T2 SPACE sequence to delineate the cranial nerve deficiencies.
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Ultrasonographic measurement of optic nerve sheath diameter (ONSD) can successfully be used to estimate intracranial pressure (ICP) elevation. Its utility in corroboration of brain death (BD) was herein studied. ⋯ ONSD is significantly greater in subjects with BD. However, quantification of ONSD cannot discriminate BD subjects from comatose ones with raised ICP with 100% certainty.
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Eddy current distortion is an important issue that may influence the quantitative measurements of diffusion tensor imaging (DTI). The corrections of eddy current artifacts could be performed using bipolar diffusion gradients or unipolar gradients with affine registration. Whether the diffusion pulse sequence affects the quantification of DTI indices and the technique that produces more reliable DTI indices in terms of reproducibility both remain unclear. ⋯ The results revealed that the reproducibility and mean values of DTI indices were significantly affected by the pulse sequence. Unipolar DTI exhibited significantly higher reproducibility than bipolar DTI even at the same TE, and the mean values of DTI indices were significantly different between them. Therefore, we concluded that the reproducibility and mean values of DTI indices were significantly influenced by diffusion pulse sequences.
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We sought to identify MRI factors associated with BBB changes at the acute stage of ischemic stroke. ⋯ BBB changes are exceptional during the first 3 hours after stroke onset. Delayed BBB alteration was associated with FLAIR positivity mainly reflecting vasogenic edema.
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Optical coherence tomography (OCT) is a modern intravascular imaging modality that has the capability to provide detailed, in vivo characterization of the arterial wall and atherosclerotic plaque. The current understanding of the appearance of atherosclerotic plaque via OCT is largely based on coronary arterial studies where OCT information has been employed to guide therapeutic management and permits the immediate evaluation of percutaneous intervention. The clinical success of OCT in the coronary arteries has laid the foundation for investigation of the carotid artery and thus, stroke risk assessment. We report the novel use of OCT for tissue characterization of severe stenosis subsequent to carotid artery stenting (CAS), both before and after treatment with cutting balloon angioplasty.