AJNR. American journal of neuroradiology
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AJNR Am J Neuroradiol · Dec 2018
Diffusional Kurtosis along the Corticospinal Tract in Adult Normal Pressure Hydrocephalus.
Normal Pressure Hydrocephalus is a reversible form of dementia characterized by enlarged ventricles, which can deform and cause disruptions to adjacent white matter fibers. The purpose of this work was to examine how diffusion and kurtosis parameters vary along the corticospinal tract and determine where along this path microstructure is compromised in patients diagnosed with normal pressure hydrocephalus. We hypothesized that disruption of the corticospinal tract from ventricular enlargement can be measured using diffusion MR imaging and this will be quantified in periventricular regions. ⋯ A lower axonal water fraction indicates a lower axonal density in the corticospinal tract, which may indicate permanent damage. Lower axial kurtosis may imply that axons are being more aligned due to compression.
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AJNR Am J Neuroradiol · Dec 2018
Imaging and Surgical Findings in Patients with Hemi-Laryngopharyngeal Spasm and the Potential Role of MRI in the Diagnostic Work-Up.
Hemi-laryngopharyngeal spasm is a recently discovered condition characterized by episodic coughing and unilateral throat contractions that may lead to severe stridor. These symptoms are caused by a vascular compression of the ipsilateral vagus nerve, typically the PICA. Microvascular decompression of the vagus nerve has been demonstrated to be a potential cure for this neurovascular compression syndrome. The main aim of this study was to clarify the role of MR imaging in the diagnostic work-up of this rare condition. ⋯ The presence of unilateral neurovascular contact or compression of the vagus nerve does not confirm the diagnosis of hemi-laryngopharyngeal spasm. The MR imaging finding of ipsilateral vascular compression of the vagus nerve is a necessary but not sufficient finding for the diagnosis of hemi-laryngopharyngeal spasm.
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AJNR Am J Neuroradiol · Dec 2018
Synthesizing a Contrast-Enhancement Map in Patients with High-Grade Gliomas Based on a Postcontrast MR Imaging Quantification Only.
Administration of a gadolinium-based contrast agent is an important diagnostic biomarker for blood-brain barrier damage. In clinical use, detection is based on subjective comparison of native and postgadolinium-based contrast agent T1-weighted images. Quantitative MR imaging studies have suggested a relation between the longitudinal relaxation rate and proton-density in the brain parenchyma, which is disturbed by gadolinium-based contrast agents. This discrepancy can be used to synthesize a contrast-enhancement map based solely on the postgadolinium-based contrast agent acquisition. The aim of this study was to compare synthetic enhancement maps with subtraction maps of native and postgadolinium-based contrast agent images. ⋯ The study shows that there was a good correlation between subtraction longitudinal relaxation enhancement maps and synthetic longitudinal relaxation enhancement maps in patients with high-grade gliomas. The method may improve the sensitivity and objectivity for the detection of gadolinium-based contrast agent enhancement.
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AJNR Am J Neuroradiol · Dec 2018
Differentiation of Hemorrhage from Iodine Using Spectral Detector CT: A Phantom Study.
Conventional CT often cannot distinguish hemorrhage from iodine extravasation following reperfusion therapy for acute ischemic stroke. We investigated the potential of spectral detector CT in differentiating these lesions. ⋯ Spectral detector CT can accurately differentiate blood from iodinated contrast in a phantom setting.
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AJNR Am J Neuroradiol · Dec 2018
Initial and Long-Term Outcomes of Complex Bifurcation Aneurysms Treated by Y-Stent-Assisted Coiling with Low-Profile Braided Stents.
Coiling complex intracranial bifurcation aneurysms often necessitates the implantation of double stents in various configurations, such as Y-stent placement. Low-profile braided stents have been introduced recently to facilitate the endovascular treatment of wide-neck aneurysms. We aimed to investigate the feasibility, safety, efficacy, and durability of Y-stent-assisted coiling with double low-profile braided stents for the treatment of complex bifurcation aneurysms. ⋯ The long-term angiographic and clinical outcomes of this retrospective study demonstrate that Y-stent-assisted coiling using low-profile braided stents is an effective, relatively safe, and durable endovascular treatment for wide-neck and complex bifurcation aneurysms.