AJNR. American journal of neuroradiology
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Magic angle effects are well recognized in MR imaging of tendons and ligaments, but have received virtually no attention in MR neurography. We investigated the hypothesis that signal intensity from peripheral nerves is increased when the nerve's orientation to the constant magnetic induction field (B(0)) approaches 55 degrees (the magic angle). ⋯ Signal intensity of peripheral nerves changes with orientation to B(0). This is probably the result of the magic angle effect from the highly ordered, linearly orientated collagen within them. Differences in signal intensity with orientation may simulate disease and be a source of diagnostic confusion.
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AJNR Am J Neuroradiol · Mar 2004
Cervical radiculopathy: open study on percutaneous periradicular foraminal steroid infiltration performed under CT control in 30 patients.
Cervical radiculopathy is a common entity that can become unremitting, seriously disrupting the patient's work and social activities. The purpose of our study was to evaluate the feasibility, tolerance, and efficacy of transforaminal periganglionic steroid infiltration under CT control. ⋯ Intraforaminal cervical infiltration produced substantial sustained pain relief, whatever the cause of the radiculalgia. The CT approach ensures the safety of vital structures and allows the precise injection of a steroid specifically targeted to the ganglia.
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AJNR Am J Neuroradiol · Mar 2004
Diffusion tensor imaging as potential biomarker of white matter injury in diffuse axonal injury.
Multiple biomarkers are used to quantify the severity of traumatic brain injury (TBI) and to predict outcome. Few are satisfactory. CT and conventional MR imaging underestimate injury and correlate poorly with outcome. New MR imaging techniques, including diffusion tensor imaging (DTI), can provide information about brain ultrastructure by quantifying isotropic and anisotropic water diffusion. Our objective was to determine if changes in anisotropic diffusion in TBI correlate with acute Glasgow coma scale (GCS) and/or Rankin scores at discharge. ⋯ DTI reveals changes in the white matter that are correlated with both acute GCS and Rankin scores at discharge. DTI may be a valuable biomarker for the severity of tissue injury and a predictor for outcome.
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AJNR Am J Neuroradiol · Mar 2004
MR imaging and spectroscopic study of epileptogenic hypothalamic hamartomas: analysis of 72 cases.
Reports of MR imaging in hypothalamic hamartomas associated with epilepsy are few, and the number of patients studied is small. We aimed to detail the relationship of hypothalamic hamartomas to surrounding structures, to determine the frequency and nature of associated abnormalities, and to gain insight into mechanisms of epileptogenesis. ⋯ Hypothalamic hamartomas can be readily distinguished from normal hypothalamic gray and adjacent myelinated fiber tracts, best appreciated on thin T2-weighted images. MR imaging and spectroscopy suggest reduced neuronal density and relative gliosis compared with normal gray matter. Associated epileptogenic lesions are rare, supporting the view that the hypothalamic hamartoma alone is responsible for the typical clinical features of the syndrome. The intimate relationship to the mammillary body, fornix, and mammillothalamic tract suggests a role for these structures in epileptogenesis associated with hypothalamic hamartomas.
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AJNR Am J Neuroradiol · Mar 2004
Retraction Of PublicationRe: Retraction request: AJNR 23: 868-870, May 2002.