Atherosclerotic Carotid Plaques: Multimodality Imaging with Contrast-enhanced Ultrasound, Computed Tomography, and Magnetic Resonance Imaging.

Introduction: The imaging of carotid plaques has undergone a paradigm shift increasing importance being given to plaque characterization. Patients with "vulnerable" plaques are more prone to develop future neurovascular events.

Purpose: The purpose of this study is to analyze the role of multimodality imaging techniques in the assessment of carotid atherosclerotic plaques.

Neuroenteric cysts of the brain-comprehensive magnetic resonance imaging.

Neuroenteric cysts are developmental cysts that should be differentiated from other, more common non-neoplastic cysts as well as cystic neoplasms. While these lesions may have varied imaging findings, T1 hyperintense prepontine lesion due to mucinous/proteinaceous content is characteristic. Location and imaging characteristics aid in formulating the correct diagnosis of neuroepithelial/neuroenteric cysts.

Multimodality imaging of carotid atherosclerotic plaque: Going beyond stenosis.

Apart from the degree of stenosis, the morphology of carotid atherosclerotic plaques and presence of neovascularization are important factors that may help to evaluate the risk and 'vulnerability' of plaques and may also influence the choice of treatment. In this article, we aim to describe the techniques and imaging findings on CTA, high resolution MRI and contrast enhanced ultrasound in the evaluation of carotid atherosclerotic plaques. We also discuss a few representative cases from our institute with the related clinical implications.

Imaging signs in idiopathic intracranial hypertension: Are these signs seen in secondary intracranial hypertension too?

Background: The purpose of this study was to evaluate the difference in the occurrence of the various "traditional" imaging signs of intracranial hypertension (IIH) on magnetic resonance imaging (MRI) in patients with idiopathic (IIH) and secondary intracranial hypertension.

Materials And Methods: In a retrospective analysis, the MRI findings of 21 patients with IIH and 60 patients with secondary intracranial hypertension (41 with tumors; 19 with intracranial venous hypertension) were evaluated for the presence or absence of various "traditional" imaging signs of IIH (perioptic nerve sheath distention, vertical buckling of optic nerve, globe flattening, optic nerve head protrusion and empty sella) using the Fisher's exact test. Odds ratios were also calculated.

Correlation between anatomic landmarks and fMRI in detection of the sensorimotor cortex in patients with structural lesions.

Background: Structural lesions in/near the sensorimotor cortex may cause distortion/obscuration of the anatomic landmarks.

Purpose: To compare the localization of the sensorimotor cortex using anatomical landmarks and fMRI in the clinical setting in patients with structural lesions in/near the central sulcus.

Material And Methods: We analyzed the anatomic and fMRI data of 68 consecutive patients (42 tumors, 15 gliotic lesions, 11 focal cortical dysplasias [FCD]) who underwent MRI to assess the relationship of these lesions to the sensorimotor cortex.

Tumefactive demyelinating lesions: a clinicopathological correlative study.

Tumefactive demyelinating (TDL) lesions are focal zones of demyelination in the central nervous system and they often mimic the neuroimaging features of an intraxial neoplasm. In this report we describe the clinical, neuroimaging and neuropathological features of six cases of TDL. Only in two patients the neuroimaging features in MRI (magnetic resonance imaging) scans were suggestive of TDL while in the other four cases a diagnosis of glioma was suggested.

'Susceptibility sign' on susceptibility-weighted imaging in acute ischemic stroke.

Background And Aim: Acute intra-arterial thrombus produces susceptibility artifact on gradient echo images (susceptibility sign). Our aim was to study the sensitivity and specificity of the susceptibility sign in various major intracranial arteries on susceptibility-weighted imaging (SWI) in patients with acute stroke. We also compared it with the 'hyperintensity sign' on fluid-attenuated inversion recovery (FLAIR) and 'hyperdense artery sign' on computed tomography (CT) for middle cerebral artery (MCA) occlusion.

Embryonal tumor with multilayered rosettes: Two case reports with a review of the literature.

Embryonal tumor with multilayered rosettes (ETMR) is a well-recognized histopathological variant of primitive neurectodermal tumors of the central nervous system. This tumor depicts histopathological features that are common to both ependymoblastoma (EBL) and neuroblastoma. Here we report two pediatric cases of ETMR, one exhibiting dominant neuronal differentiation and the other with dominant glial differentiation, thereby expanding the previously known pathologic spectrum.

Tanycytic ependymoma of filum terminale: a case report.

Tanycytic ependymoma is an uncommon but well-recognized variant of ependymoma. Here we report a case of tanycytic ependymoma occurring at the region of filum terminale in a 44-year male who presented with low backache, bilateral lower limb weakness and urinary incontinence. MR imaging in this patient showed a lesion that was composed of solid and cystic components and was suggestive of ependymoma.

Spontaneous intracranial hypo and hypertensions: an imaging review.

Cerebrospinal fluid (CSF) pressure changes can manifest as either intracranial hypertension or hypotension. The idiopathic forms are largely under or misdiagnosed. Spontaneous intracranial hypotension occurs due to reduced CSF pressure usually as a result of a spontaneous dural tear.

Applications of 3D CISS sequence for problem solving in neuroimaging.

Three-dimensional (3D) constructive interference in steady state (CISS) is a gradient-echo MRI sequence that is used to investigate a wide range of pathologies when routine MRI sequences do not provide the desired anatomic information. The increased sensitivity of the 3D CISS sequence is an outcome of the accentuation of the T2 values between cerebrospinal fluid (CSF) and pathological structures. Apart from its well-recognized applications in the evaluation of the cranial nerves, CSF rhinorrhea and aqueduct stenosis, we have found the CISS sequence to be useful for the cisternal spaces, cavernous sinuses and the ventricular system, where it is useful for detecting subtle CSF-intensity lesions that may be missed on routine spin-echo sequences.

Clinical utility of susceptibility-weighted imaging in vascular diseases of the brain.

Susceptibility-weighted imaging (SWI) is a rapidly evolving technique that utilizes both the magnitude and phase information to obtain valuable information about susceptibility changes between tissues. SWI is very sensitive to the paramagnetic effects of deoxyhemoglobin. SWI plays an important role in the diagnostic evaluation and management of acute stroke.

Colloid cyst of the velum interpositum: a common lesion at an uncommon site.

Background: Colloid cysts are typically located in the region of the anterior third ventricle in the proximity of foramen of Monro. Although 'endodermal cyst' has been identified in several regions of the brain, location of characteristic colloid cyst entirely within the confines of velum interpositum and outside the ventricles has not been reported earlier.

Case Description: We report a unique case of colloid cyst located in the region of velum interpositum in a 33-year-old patient with headache and seizures.