Mesoscopic Assessment of Microstructure in Glioblastomas and Metastases by Merging Advanced Diffusion Imaging with Immunohistopathology.

Background And Purpose: Glioblastomas and metastases are the most common malignant intra-axial brain tumors in adults and can be difficult to distinguish on conventional MR imaging due to similar imaging features. We used advanced diffusion techniques and structural histopathology to distinguish these tumor entities on the basis of microstructural axonal and fibrillar signatures in the contrast-enhancing tumor component.

Materials And Methods: Contrast-enhancing tumor components were analyzed in 22 glioblastomas and 21 brain metastases on 3T MR imaging using DTI-fractional anisotropy, neurite orientation dispersion and density imaging-orientation dispersion, and diffusion microstructural imaging-micro-fractional anisotropy.

The value of qualitative and quantitative assessment of lesion to cerebral cortex signal ratio on double inversion recovery sequence in the differentiation of demyelinating plaques from non-specific T2 hyperintensities.

Objectives: To assess the usefulness of the visual assessment and to determine diagnostic value of the lesion-to-cerebral cortex signal ratio (LCSR) measurement in the differentiation of demyelinating plaques and non-specific T2 hyperintensities on double inversion recovery (DIR) sequence.

Material And Methods: DIR and fluid-attenuated inversion recovery (FLAIR) sequences of 25 clinically diagnosed multiple sclerosis (MS) patients and 25 non-MS patients with non-specific T2-hyperintense lesions were evaluated visually and LCSRs were measured by two observers independently.

Results: On DIR sequence, the calculated mean LCSR ± SD for demyelinating plaques and non-specific T2-hyperintense lesions were 1.

Malformations of cortical development: 3T magnetic resonance imaging features.

Malformation of cortical development (MCD) is a term representing an inhomogeneous group of central nervous system abnormalities, referring particularly to embriyological aspect as a consequence of any of the three developmental stages, i.e., cell proliferation, cell migration and cortical organization.

Metastasis of Breast Carcinoma to the External Auditory Canal: Report of an Unusual Case and Literature Review.

We present a case of metastasis of the external auditory canal (EAC) from a primary breast carcinoma in a 53-year-old female with a review of the literature. The patient had been diagnosed with a primary carcinoma 4 years previously. The metastasis had developed recently in her left EAC and presented as a bulky, fleshy, bleeding mass.

Split-bolus MR urography: synchronous visualization of obstructing vessels and collecting system in children.

Several vascular abnormalities related with urinary system such as crossing accessory renal vessels, retroiliac ureters, retrocaval ureters, posterior nutcracker syndrome, and ovarian vein syndrome may be responsible for urinary collecting system obstruction. Split-bolus magnetic resonance urography (MRU) using contrast material as two separate bolus injections provides superior demonstration of the collecting system and obstructing vascular anomalies simultaneously and enables accurate preoperative radiologic diagnosis. In this pictorial review we aimed to outline the split-bolus MRU technique in children, list the coexisting congenital collecting system and vascular abnormalities, and exhibit the split-bolus MRU appearances of concurrent urinary collecting system and vascular abnormalities.

Brain herniations into the dural venous sinus or calvarium: MRI findings, possible causes and clinical significance.

Objectives: To determine frequency, imaging features and clinical significance of herniations of brain parenchyma into dural venous sinuses (DVS) and/or calvarium found on MRI.

Methods: A total of 6160 brain MRI examinations containing at least one high-resolution T1- or T2-weighted sequence were retrospectively evaluated to determine the presence of incidental brain herniations into the DVS or calvarium. MRI sequences available for review were evaluated according to their capability to demonstrate these herniations.

MRI diagnosis of dural sinus - Cortical venous thrombosis: Immediate post-contrast 3D GRE T1-weighted imaging versus unenhanced MR venography and conventional MR sequences.

Objective: Primary aim is to compare the diagnostic value of contrast-enhanced 3D GRE T1-weighted sequences with unenhanced MR venography and conventional magnetic resonance imaging (MRI), in detection of dural venous sinus (DVS) and cortical venous thrombosis; secondary aim is to determine the relationship between DVS thrombosis/site and gender, age, infarction or hemorrhage.

Methods: We retrospectively reviewed conventional MR images, unenhanced MR venography and immediate post-contrast 3D GRE T1-weighted MR images in 30 patients (17 male and 13 female, 21-70 years old, mean age 40.1) with clinically suspected DVS thrombosis.

Measures of ventricles and evans' index: from neonate to adolescent.

Ventricle sizes are important for the early diagnosis of hydrocephalus or for follow-up after ventriculostomy. Diameters of ventricles may change, especially in childhood. This study aims to provide normative data about ventricle diameters.

Measures of pituitary gland and stalk: from neonate to adolescence.

Objective: The aim of this study is to provide normative data about pituitary diameters in a pediatric population. Pituitary imaging is important for the evaluation of the hypothalamo-pituitary axis defect. However, data about normal pituitary gland diameters and stalk are limited, especially in children.

Prevalence of dual left anterior descending artery variations in CT angiography.

Purpose: We aimed to evaluate the frequency and features of dual left anterior descending artery (LAD) variants using computed tomography (CT) angiography.

Methods: A total of 1337 consecutive coronary CT angiography examinations performed between April 2010 and December 2013 were retrospectively evaluated for the presence of dual LAD. CT examinations were performed with either 64- or 320-row multidetector CT scanners.