Andrew J Steven

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Functional imaging modalities, such as functional magnetic resonance imaging (fMRI) and diffusion tensor imaging (DTI), are rapidly changing the scope and practice of neuroradiology. While these modalities have long been used in research, they are increasingly being used in clinical practice to enable reliable identification of eloquent cortex and white(More)
OBJECTIVE Diffusion kurtosis imaging is an emerging technique based on the non-gaussian diffusion of water in biologic systems. The purpose of this article is to introduce and discuss the ongoing research and potential clinical applications of this technique. CONCLUSION Diffusion kurtosis imaging provides independent and complementary information to that(More)
BACKGROUND Interlaminar epidural steroid injections (ILESIs) are commonly employed in the management of patients with symptomatic degenerative lumbar spinal canal stenosis despite little experimental evidence to guide technique optimization. One untested performance parameter is the intervertebral level at which the ILESI should be performed for maximum(More)
MR imaging is an extremely useful tool in the evaluation of traumatic brain injury in the emergency department. Although CT still plays the dominant role in urgent patient triage, MR imaging's impact on traumatic brain injury imaging continues to expand. MR imaging has shown superiority to CT for certain traumatic processes, such as diffuse axonal injury,(More)
Although tinnitus may originate in damage to the peripheral auditory apparatus, its perception and distressing symptomatology are consequences of alterations to auditory, sensory, and limbic neural networks. This has been described in several studies, some using advanced structural MR imaging techniques such as diffusion tensor imaging. An understanding of(More)
Cerebral venous sinus thrombosis is an elusive diagnosis with profound potential neurologic consequences. Although there are numerous reported predisposing conditions, by far the most common is a prothrombotic hypercoagulable state. Recent advances in MRI and computed tomography have improved diagnostic accuracy for this increasingly recognized disorder.(More)
OBJECTIVE Dorsal arachnoid webs (DAWs) and spinal cord herniation (SCH) are uncommon abnormalities affecting the thoracic spinal cord that can result in syringomyelia and significant neurological morbidity if left untreated. Differentiating these 2 entities on the basis of clinical presentation and radiological findings remains challenging but is of vital(More)
INTRODUCTION Hyperglycemia can induce hemichorea-hemiballism, especially in elderly type II diabetics. CT and MRI findings include hyperdensity and T1-shortening in the contralateral lentiform nucleus, respectively. This study explores the associated imaging findings on T2*-based sequences. METHODS Six patients with clinically documented(More)
Infections are rare but important causes of stroke. Among these, varicella zoster virus has been known to cause ischemic stroke. During an attack of herpes zoster ophthalmicus, it has been hypothesized that the virus replicates in the trigeminal ganglion and travels via the trigeminal nerve centrally to cause cerebral vasculopathy. Here we present a case of(More)