Predictive values of spinal cord diffusion magnetic resonance imaging to characterize outcomes after contusion injury.

Objectives: To explore filtered diffusion-weighted imaging (fDWI), in comparison with conventional magnetic resonance imaging (MRI) and diffusion tensor imaging (DTI), as a predictor for long-term locomotor and urodynamic (UD) outcomes in Yucatan minipig model of spinal cord injury (SCI). Additionally, electrical conductivity of neural tissue using D-waves above and below the injury was measured to assess correlations between fDWI and D-waves data.

Methods: Eleven minipigs with contusion SCI at T8-T10 level underwent MRI at 3T 4 h.

Multi-Site Spinal Cord Transcutaneous Stimulation Facilitates Upper Limb Sensory and Motor Recovery in Severe Cervical Spinal Cord Injury: A Case Study.

Individuals with cervical spinal cord injury (SCI) rank regaining arm and hand function as their top rehabilitation priority post-injury. Cervical spinal cord transcutaneous stimulation (scTS) combined with activity-based recovery training (ABRT) is known to effectively facilitate upper extremity sensorimotor recovery in individuals with residual arm and hand function post SCI. However, scTS effectiveness in facilitating upper extremity recovery in individuals with severe SCI with minimal to no sensory and motor preservation below injury level remains largely unknown.

Spinal cord imaging markers and recovery of standing with epidural stimulation in individuals with clinically motor complete spinal cord injury.

Spinal cord epidural stimulation (scES) is an intervention to restore motor function in those with severe spinal cord injury (SCI). Spinal cord lesion characteristics assessed via magnetic resonance imaging (MRI) may contribute to understand motor recovery. This study assessed relationships between standing ability with scES and spared spinal cord tissue characteristics at the lesion site.

Spinal Cord Imaging Markers and Recovery of Volitional Leg Movement With Spinal Cord Epidural Stimulation in Individuals With Clinically Motor Complete Spinal Cord Injury.

Previous studies have shown that epidural stimulation of the lumbosacral spinal cord (scES) can re-enable lower limb volitional motor control in individuals with chronic, clinically motor complete spinal cord injury (SCI). This observation entails that residual supraspinal connectivity to the lumbosacral spinal circuitry still persisted after SCI, although it was non-detectable when scES was not provided. In the present study, we aimed at exploring further the mechanisms underlying scES-promoted recovery of volitional lower limb motor control by investigating neuroimaging markers at the spinal cord lesion site magnetic resonance imaging (MRI).

ECG Gating Is More Precise Than Peripheral Pulse Gating When Quantifying Spinal CSF Pulsations Using Phase Contrast Cine MRI.

Purpose: To compare accuracy of spinal cerebrospinal fluid (CSF) pulsatile flow measurements at cervical, thoracic, and lumbar levels using Phase Contrast Cine MRI (PCCMRI) with retrospective electrocardiogram (recg) vs. retrospective peripheral pulse gating (rppg) gating.

Methods: We scanned 10 healthy volunteers, ages 23-46 years, using external recg-gated or rppg-gated 2D PCCCMRI at 3T.

The relationships among spinal CSF flows, spinal cord geometry, and vascular correlations: evidence of intrathecal sources and sinks.

We studied relationships of cerebral spinal fluid (CSF) pulsatile flow at cervical, thoracic, and lumbar levels using phase-contrast cine MRI (PCCMRI) to determine the following: ) instantaneous and average net flows at cervical, thoracic, and lumbar levels, ) stochastic correlations of CSF flow with major arterial supplies and major draining veins, and ) whether adjustments of cord-flow curves-using cord cross-sectional areas, caudal lengths, and caudal volumes-would normalize flow curves from different levels. We scanned 15 healthy volunteers without anesthesia, ages 23-46 yr, using external, retrocardiac-gated, two-dimensional PCCMRI at 3T. Transverse scans of the subarachnoid space, arteries, and veins were acquired and analyzed at cervical, thoracic, and lumbar levels.

Incorporating shape prior into active contours with a sparse linear combination of training shapes: application to corpus callosum segmentation.

In this paper, a novel method of embedding shape information into level set image segmentation is proposed. Our method is based on inferring shape variations by a sparse linear combination of instances in the shape repository. Given a sufficient number of training shapes with variations, a new shape can be approximated by a linear span of training shapes associated with those variations.

Distribution of Cervical Lymph Node Metastases From Squamous Cell Carcinoma of the Oropharynx in the Era of Risk Stratification Using Human Papillomavirus and Smoking Status.

Purpose/objective(s): To investigate the factors contributing to the clinical presentation of oropharyngeal squamous cell carcinoma (OPSCC) in the era of risk stratification using human papilloma virus (HPV) and smoking status.

Methods And Materials: All patients with OPSCC presenting to our institutional multidisciplinary clinic from January 2009 to June 2015 were reviewed from a prospective database. The patients were grouped as being at low risk, intermediate risk, and high risk in the manner described by Ang et al.

Varicella zoster virus in the temporal artery of a patient with giant cell arteritis.

We recently detected varicella zoster virus (VZV) in the temporal arteries (TA) of 5/24 patients with clinically suspect giant cell arteritis (GCA) whose TAs were GCA-negative pathologically; in those GCA-negative, VZV+TAs, virus antigen predominated in the arterial adventitia, but without medial necrosis and multinucleated giant cells. During our continuing search for VZV antigen in GCA-negative TAs, in the TA of one subject, we found abundant VZV antigen, as well as VZV DNA, in multiple regions (skip areas) of the TA spanning 350 μm, as well as in skeletal muscle adjacent to the infected TA. Additional pathological analysis of sections adjacent to those containing viral antigen revealed inflammation involving the arterial media and abundant multinucleated giant cells characteristic of GCA.

Zoster paresis: asymptomatic MRI lesions far beyond the site of rash and focal weakness.

We describe a patient with zoster paresis and an MRI that revealed extensive spinal cord lesions from the upper cervical to the lower thoracic spinal cord. Importantly, the patient reported considerable spontaneous improvement in strength 2-3 weeks after zoster. This report reveals a previously undescribed remarkable preponderance of MRI lesions far beyond the site of zoster rash and focal lower motor neuron weakness.

Recognizing false ischemic penumbras in CT brain perfusion studies.

Computed tomography (CT) plays a pivotal role in the diagnosis of acute stroke and in treatment decision making. CT perfusion imaging performed with intravenous iodinated contrast material allows calculation of the time to peak enhancement, mean transit time, and cerebral blood volume, important parameters for differentiating between an ischemic penumbra, which might benefit from intravascular therapy with thrombolytic agents, and infarcted tissue, which would not benefit from such therapy. Differentiation between the two entities is important because thrombolytic therapy is associated with an increased risk for intracranial hemorrhage.

T(1) and T(2) measurements of the fine structures of the in vivo and enucleated human eye.

Purpose: To measure T(1) and T(2) of the fine structures of the in vivo eye.

Materials And Methods: Involuntary saccades make it difficult to obtain artifact-free images. Using a method recently reported (Bert et al, Acad Radiol 2006;12:368-378), near artifact-free spin-echo images were obtained.

Demonstration of an anterior diffusional pathway for solutes in the normal human eye with high spatial resolution contrast-enhanced dynamic MR imaging.

Purpose: The present studies were conducted to determine whether a diffusional pathway for solutes exists from the ciliary body stroma to the anterior chamber of the human eye. The existence of such a pathway has been demonstrated in rabbits and monkeys, but such a pathway in humans would necessitate a shift in the physiological paradigm of the blood-aqueous barrier.

Methods: Seven normal human volunteers (five men, two women; age range, 27 to 59 years) underwent nine dynamic T1-weighted, spin-echo MR imaging studies, using intravenous, gadolinium-based contrast agents.

High-resolution MR imaging of the human eye 2005.

Rationale And Objectives: We studied preparatory strategies for high-resolution human eye in vivo imaging with commercially available magnets and coils.

Materials And Methods: We imaged normal volunteers on 1.5T systems by Philips, GE, and Siemens, using commercial approximately 9 cm temporomandibular joint receive coils.

CNS MR and CT findings associated with a clinical presentation of herpetic acute retinal necrosis and herpetic retrobulbar optic neuritis: five HIV-infected and one non-infected patients.

Introduction: This report demonstrates the spectrum of central nervous system (CNS) abnormalities observed on MR imaging and CT studies in 6 patients with clinical or pathologic diagnoses of acute retinal necrosis (ARN) and retrobulbar optic neuritis (RBON-H) resulting from Herpes Zoster Virus and Cytomegalovirus. We discuss the etiologic and pathophysiologic implications regarding these findings.

Methods: Standard MR imaging sequences of the whole brain and selected high-resolution images of the orbits and globes, from 6 patients, were reviewed by three neuroradiologists for consensus interpretation of the findings.