Journal of neuroimaging : official journal of the American Society of Neuroimaging
-
Controlled Clinical Trial
No signs of intracranial arterial vasoconstriction in transient global amnesia.
The current theories to explain the pathophysiology of transient global amnesia (TGA) involve epilepsy, migraine, and hippocampal ischemia which might be determined by venous congestion or arterial vasoconstriction triggered by Valsalva-associated maneuvers in susceptible individuals. ⋯ Extra-intracranial atherosclerosis does not play a pathogenic role in TGA and no supporting evidence for the arterial vasoconstriction hypothesis of TGA emerged from this study.
-
Basilar artery stenosis where flow restriction constitutes the main pathomechanism are exceptional. Here, we report a case where the lesion progression was characterized by watershed infarct between the anterior inferior-superior cerebellar arteries and deep pontine arteries, indicating a significant hemodynamic impairment.
-
Atrophy of the corpus callosum is a recognized characteristic of multiple sclerosis (MS). We describe a new reliable method for measuring corpus callosum atrophy and correlate this with global cerebral atrophy measures. ⋯ Measurement of atrophy of the corpus callosum can have sensitivity as a useful imaging biomarker in patients with MS, even in patients with low disability levels. Both gray and white matter involvement in MS contribute to corpus callosum atrophy.
-
Case Reports
Benefit of cone-beam CT angiography in visualizing aneurysm shape and identification of exact rupture site.
While high-resolution cone-beam computational tomographic (CBCT) angiography has gained use in intracranial vascular imaging, digital subtraction angiography (DSA) and 3-dimensional-rotational angiography (3D-RA) remain the preferred acquisition modalities for intracranial aneurysm imaging. This case report highlights the utility of the greater spatial resolution afforded by CBCT for cerebral aneurysm imaging. A 54-year-old man presenting with subarachnoid hemorrhage was confirmed to harbor a ruptured anterior communicating artery aneurysm by conventional angiography. ⋯ The greater resolution of CBCT revealed in an unequivocal fashion the exact site of rupture on the aneurysm dome, visualized as a discrete irregular and elongated bleb that was not seen on either 3D-RA or DSA. High-resolution CBCT visualized the shape of the target aneurysm in greater detail than the more conventional 2D-DSA and 3D-RA, enabling more precise computational fluid dynamics (CFD) simulations. Given that aneurysms most likely change shape either prior to rupture or upon rupture, future studies evaluating fluid dynamics using computer reconstructions should be cognizant of the differences in resolution provided by various imaging modalities.
-
Relapsing polychondritis is a rare autoimmune disease characterized by inflammation of cartilaginous tissues. It may be associated with systemic and cerebral vasculitis and exceptionally with ischemic stroke. Brain infarction associated with internal carotid artery thrombus, in a setting of relapsing polychondritis, has never been reported. ⋯ The patient was treated with high-dose tinzaparin and was followed with serial ultrasound. After 16 days, the thrombus demonstrated a hypoechogenic core surrounded by a hyperechogenic rim and the following day it resolved completely. Thrombus formation on a small unruptured plaque may reflect involvement by relapsing polychondritis of the intimal proteoglycans that hold a role in the development of atheromatosis.