Background And Objectives: Large vessel vasculopathy (LVV), or moyamoya syndrome, increases the risk of stroke in patients with sickle cell disease (SCD), yet effective treatments are lacking. In atherosclerotic carotid disease, previous studies demonstrated elevated oxygen extraction fraction (OEF) as a predictor of ipsilateral stroke. In a SCD cohort, we examined hemispheric hemodynamic and oxygen metabolic dysfunction as tissue-based biomarkers of cerebral ischemic risk in patients with LVV.
View Article and Find Full Text PDFAlthough hemodynamic stress plays a key role in aneurysm formation outside of sickle cell disease (SCD), its role is understudied in patients with SCD. We hypothesized that tissue-based markers of hemodynamic stress are associated with aneurysm presence in a prospective SCD cohort. Children and adults with SCD, with and without aneurysms, underwent longitudinal brain magnetic resonance imaging/magnetic resonance angiography (MRA) to assess cerebral blood flow (CBF) and oxygen extraction fraction (OEF).
View Article and Find Full Text PDFObjective: A major shortcoming in optimizing care for patients with cervical spondylotic myelopathy (CSM) is the lack of robust quantitative imaging tools offered by conventional MRI. Advanced MRI modalities, such as diffusion MRI (dMRI), including diffusion tensor imaging (DTI) and diffusion basis spectrum imaging (DBSI), may help address this limitation by providing granular evaluations of spinal cord microstructure.
Methods: Forty-seven patients with CSM underwent comprehensive clinical assessments and dMRI, followed by DTI and DBSI modeling.
Background: Silent cerebral infarcts (SCI) in sickle cell anemia (SCA) are associated with future strokes and cognitive impairment, warranting early diagnosis and treatment. Detection of SCI, however, is limited by their small size, especially when neuroradiologists are unavailable. We hypothesized that deep learning may permit automated SCI detection in children and young adults with SCA as a tool to identify the presence and extent of SCI in clinical and research settings.
View Article and Find Full Text PDFHRCT-MRI fusion is a new imaging modality that can be used to diagnose spontaneous CSF leaks. HRCT-MRI fusion has better accuracy in localizing CSF leaks compared to MRI and HRCT alone.
View Article and Find Full Text PDFBackground: Individuals with sickle cell anemia have heightened risk of stroke and cognitive dysfunction. Given its high prevalence globally, whether sickle cell trait (SCT) is a risk factor for neurological injury has been of interest; however, data have been limited. We hypothesized that young, healthy adults with SCT would show normal cerebrovascular structure and hemodynamic function.
View Article and Find Full Text PDFObjective: To determine the patient- and tissue-based relationships between cerebral hemodynamic and oxygen metabolic stress, microstructural injury, and infarct location in adults with sickle cell disease (SCD).
Methods: Control participants and patients with SCD underwent brain MRI to quantify cerebral blood flow (CBF), oxygen extraction fraction (OEF), mean diffusivity (MD), and fractional anisotropy (FA) within normal-appearing white matter (NAWM) and infarcts on fluid-attenuated inversion recovery. Multivariable linear regression examined the patient- and voxel-based associations between hemodynamic and metabolic stress (defined as elevated CBF and OEF, respectively), white matter microstructure, and infarct location.
Background And Purpose: Visualization of annular fissures on MRI is becoming increasingly important but remains challenging. Our purpose was to test whether an image processing algorithm could improve detection of annular fissures.
Materials And Methods: In this retrospective study, two neuroradiologists identified 56 IVDs with annular fissures and 97 IVDs with normal annulus fibrosus in lumbar spine MRIs of 101 patients (58 M, 43 F; age ± SD 15.
The computer-aided design of individual parts and the desire for weight reduction and material savings require further development of new hybrid materials. Ni/PU hybrid foams as a new hybrid material offer great potential for the production of components that are lightweight and yet can absorb large amounts of energy. The development of this structured material is at its beginning and mechanical characterisation on all scales is necessary.
View Article and Find Full Text PDFNeuroimaging plays an important role in the management of head trauma. Several guidelines have been published for identifying which patients can avoid neuroimaging. Noncontrast head CT is the most appropriate initial examination in patients with minor or mild acute closed head injury who require neuroimaging as well as patients with moderate to severe acute closed head injury.
View Article and Find Full Text PDFJ Comput Assist Tomogr
August 2016
Objective: This study aimed to determine the correlation between thyroid computed tomography (CT) density and thyroid functional status.
Methods: Thyroid CT densities were determined in patients who had a noncontrast CT of the cervical spine and a recent thyroid-stimulating hormone (TSH) measurement in a cohort of 157 patients. Thyroid CT densities of patients with abnormally low TSH and high TSH were compared to those with normal TSH.
Encephalocraniocutaneous lipomatosis (ECCL) is a rare congenital syndrome with an unknown etiology. Since 1970, around 60 cases have been reported in English literature. ECCL is usually classified by cutaneous lesions and non-progressive intracranial or spinal lipomas; however three cases of ECCL associated with low grade glioma (LGG) have been described.
View Article and Find Full Text PDFWe report a case of a four-year-old male who presented with symptoms of brainstem compression and lower cranial nerve neuropathies. MRI revealed a large, pre-pontine mass causing brainstem compression with an uncertain intra-axial component. Using diffusion tensor imaging (DTI) tractography and other imaging modalities, we were able to confirm that the lesion was extra-axial and did not involve the corticospinal tracts.
View Article and Find Full Text PDFObjective: The objective of our study was to compare the cost-effectiveness of two approaches to using MRI for the evaluation of patients with hearing loss.
Materials And Methods: We developed a decision tree to compare the cost-effectiveness of conventional MRI with that of a proposed two-tiered model in which an initial 3D T2-weighted imaging examination was used to determine the need for comprehensive MR scanning. Three radiologists independently and blindly reviewed the 3D T2-weighted images acquired as part of the comprehensive MR examinations of 256 patients with hearing loss to assess the diagnostic efficacy of the two-tiered approach.
Objective: The purpose of this study was to compare the diagnostic efficacy and cost implications of a proposed two-tiered approach to MRI in patients with headache.
Materials And Methods: We identified 245 consecutive patients with headache using MRI studies performed at a tertiary care facility between October 2009 and July 2011. Three radiologists prospectively used FLAIR sequences from these MR studies to diagnose underlying abnormality or to identify the need for a comprehensive MRI study.