Myoinositol as a Biomarker in Recurrent Glioblastoma Treated with Bevacizumab: A 1H-Magnetic Resonance Spectroscopy Study.

Background: Antiangiogenic treatment of glioblastomas with Bevacizumab lacks predictive markers. Myoinositol (MI) is an organic osmolyte, with intracellular concentration changes depending on the extracellular osmolality. Since Bevacizumab markedly reduces tumor edema and influences the tumor microenvironment, we investigated whether the MI concentration in the tumor changes during therapy.

Spectroscopic Characterization of Gliosarcomas-Do They Differ From Glioblastomas and Metastases?

Objective: To evaluate the spectroscopic pattern of gliosarcomas for differentiation from glioblastomas or metastases.

Methods: H-nuclear magnetic resonance (NMR) spectroscopic intermediate echo time data of 5 patients with histologically proven gliosarcomas were compared with data of 17 metastases and 54 glioblastomas. Specialized H-NMR spectroscopy analysis software was used offline.

T2'- and PASL-based perfusion mapping at 3 Tesla: influence of oxygen-ventilation on cerebral autoregulation.

Purpose: To use T2'-mapping together with Pulsed Arterial Spin Labeling (PASL) providing quantitative information of deoxygenation level and cerebral blood flow (CBF) in the cerebral gray matter to obtain simultaneous information about the cerebral oxygen metabolism and the resulting cerebral vasoreactivity under normoxic and hyperoxic conditions.

Materials And Methods: Twelve young, healthy volunteers underwent MRI under normoxic and hyperoxic conditions performing PASL and high-resolution, motion-corrected T2* and T2-mapping to calculate T2'values. Regions of interest (ROI) were placed in the frontoparietal cortex and thalamus by manual and automatic segmentation.

Morphometry and diffusion MR imaging years after childhood traumatic brain injury.

Objective: Our goal was to detect possible unrecognized injury in cerebral white matter (WM) in adult survivors of traumatic brain injury (TBI) during childhood, who showed no detectable axonal injury or chronic contusion on late conventional MRI.

Material And Methods: We used voxel-based morphometry (VBM) to detect subtle structural changes in brain morphology and diffusion-tensor imaging (DTI) to non-invasively probe WM integrity. By means of VBM and DTI we examined a group of 12 adult patients who suffered from childhood closed head injury without axonal injury on late conventional MRI.

MR spectroscopy differentiation between high and low grade astrocytomas: a comparison between paediatric and adult tumours.

Objective: To investigate whether pathologically similar astrocytomas in adults and children may also show metabolic similarities in proton magnetic resonance spectroscopy ((1)H-MRS) and whether the MRS data could help to differentiate between low and high grade gliomas for the different groups.

Material And Methods: Twelve children (5 WHO II astrocytomas, 7 WHO III astrocytomas) and 37 adults (21 WHO II astrocytomas, 16 WHO III astrocytomas) were included in this study. MR spectroscopic data were evaluated retrospectively using normalized measures of total choline (tCho), N-acetyl-aspartate (NAA) and total creatine (tCr).

Stripe-like increase of rCBV beyond the visible border of glioblastomas: site of tumor infiltration growing after neurosurgery.

We observed a stripe-like pattern of regional cerebral blood volume (rCBV) increase in a defined region adjacent to the contrast enhancement (CE) on MRI of glioblastomas (GBM) that we defined as the "striate sign" (SS). We hypothesized that the SS marks infiltration of GBM outside the CE volume transforming into future CE tumor in the follow-up. T2*-weighted dynamic susceptibility-weighted CE (DSC)-MRI, and T1 and T2-weighted images (WI) of 16 patients with GBM were retrospectively evaluated in a baseline MRI performed before neurosurgery.

Metabolism and regional cerebral blood volume in autoimmune inflammatory demyelinating lesions mimicking malignant gliomas.

Dynamic susceptibility contrast (DSC) magnetic resonance imaging (MRI) and MR spectroscopy are thought to differentiate tumefactive autoimmune inflammatory demyelinating lesions from glial brain tumours. The aim of this work is to evaluate whether regional cerebral blood volume (rCBV), as well as choline (Cho), N-acetyl-aspartate (NAA) and myo-inositol (mIns) concentrations differ between tumefactive lesions and World Health Organization (WHO) grade II-III gliomas. Five patients with single autoimmune inflammatory demyelinating lesions and nine patients with WHO grade II and III gliomas were examined by DSC-MRI and by two-dimensional (2D) 1H MR spectroscopic imaging (1H-MRSI).

Leptomeningeal metastases in pediatrics: magnetic resonance image manifestations and correlation with cerebral spinal fluid cytology.

Background: Detection of leptomeningeal metastases is fundamental to a complete evaluation of central nervous system (CNS) or non-CNS tumor with suspected involvement of the neuroaxis. Our purpose was to assess the appearances of different magnetic resonance (MR) sequences in the diagnosis of leptomeningeal metastases and correlate those positive findings with the cerebral spinal fluid (CSF) cytology results.

Methods: The authors reviewed the medical records and MR image manifestations of leptomeningeal metastases from 18 children who had positive MR findings and retrospectively correlated them with CSF cytologic results.

MR angiography in patients with subarachnoid hemorrhage: adequate to evaluate vasospasm-induced vascular narrowing?

The diagnosis of cerebral vasospasm (CVS) following subarachnoid hemorrhage (SAH) is still challenging. We evaluate the accuracy of time of flight MR angiography (TOF-MRA) to assess the arterial diameters of the circle of Willis in SAH patients with suspected CVS. MR examinations (1.

Diffusion tensor imaging in patients with adult chronic idiopathic hydrocephalus.

Objective: Diffusion tensor imaging (DTI) parameters were investigated in patients with chronic idiopathic hydrocephalus to evaluate microstructural changes of brain tissue caused by chronic ventricular dilatation.

Methods: Eleven patients fulfilling the criteria for possible or probable idiopathic normal pressure hydrocephalus and 10 healthy control subjects underwent MRI at 3 Tesla, including DTI with 12 gradient directions. Patients were scanned before lumbar cerebrospinal fluid (CSF) withdrawal tests.

Toxic leukoencephalopathy after heroin abuse without heroin vapor inhalation: MR imaging and clinical features in three patients.

Background And Purpose: Toxic leukoencephalopathy has been associated with illicit heroin vapor inhalation. Despite the nonspecific and variable clinical presentation of these patients, they show typical radiologic findings. Previous studies evaluated typical radiologic findings with symmetric infratentorial hyperintense signal changes and similar alteration in the posterior limb of the internal capsule, the splenium of corpus callosum, the medial lemniscus and the lateral brainstem.

The role of magnetic resonance imaging in children with hematogenous brain metastases from primary solid tumors.

Within a 10-year period, 4 out of 429 children with solid tumors treated at the pediatric oncology department developed brain metastases. Lesions secondary to direct extension from the skull or dura were excluded. The tumors causing brain metastases were non-small cell lung carcinoma, Wilms' tumor, osteosarcoma, und hepatoblastoma.

The striate sign: peritumoural perfusion pattern of infiltrative primary and recurrent gliomas.

MR perfusion depicts angiogenesis as a key factor for growth and malignancy in gliomas by means of increased regional cerebral blood volume (rCBV). The rCBV increase is not limited to the tumour area, but may also produce a stripe-like pattern of peritumoural rCBV increase that we defined as the "striate sign". We evaluated if prior radiochemotherapy influences perfusion values and pattern in and adjacent to malignant gliomas comparing rCBV of treated recurrent gliomas with untreated gliomas.

Cerebral gliomas: diffusional kurtosis imaging analysis of microstructural differences.

Purpose: To characterize the non-Gaussian diffusion patterns of cerebral glioma microstructure with respect to the different glioma grades by using a new method called diffusional kurtosis (DK) imaging.

Materials And Methods: In this study with institutional review board approval and patient consent, diffusional measures of mean kurtosis (MK), fractional anisotropy (FA), and apparent diffusion coefficient (ADC) were compared prospectively. Data were normalized to the contralateral white matter.

Phosphorus and proton magnetic resonance spectroscopy demonstrates mitochondrial dysfunction in early and advanced Parkinson's disease.

Mitochondrial dysfunction hypothetically contributes to neuronal degeneration in patients with Parkinson's disease. While several in vitro data exist, the measurement of cerebral mitochondrial dysfunction in living patients with Parkinson's disease is challenging. Anatomical magnetic resonance imaging combined with phosphorus and proton magnetic resonance spectroscopic imaging provides information about the functional integrity of mitochondria in specific brain areas.

Intracranial stenting of atherosclerotic stenoses: current status and perspectives.

The purpose of this review article is to give an overview of the current development of intracranial stenting for treatment of atherosclerotic stenoses. Natural history and methods for diagnostic imaging are described as basis for the indication for endovascular treatment. Target group are patients with high-grade symptomatic stenoses > 70%.

The interdisciplinary treatment of unruptured intracranial aneurysms.

Introduction: The purpose of this article is to present the results of microsurgical clipping or endovascular coil obliteration of unruptured intracranial aneurysms (UIA), in a single cerebrovascular center with regard to successful obliteration and periprocedural complications.

Methods: Data concerning patients with UIA were recorded in the neurovascular database of the neurosurgical department at the University of Frankfurt. The outcome of treatment was assessed with the modified Rankin Scale.

A standardised evaluation of pre-surgical imaging of the corticospinal tract: where to place the seed ROI.

The aim of the study was to compare the different approaches of pre-operative diffusion-tensor-imaging-based fibre tracking (FT) of the corticospinal tract (CST) focusing on the positioning of the seeding region of interest (seed ROI). Thirty-nine patients with brain lesions in the vicinity of the CST were evaluated pre-operatively. Imaging comprised a 3D T1-weighted sequence, a gradient echo echo-planar imaging sequence for functional magnetic resonance imaging (fMRI), and a diffusion-weighted sequence for diffusion tensor (DT) tractography.

Conversion to dementia in mild cognitive impairment is associated with decline of N-actylaspartate and creatine as revealed by magnetic resonance spectroscopy.

The purpose of the present study was to longitudinally track changes of metabolite markers detectable by magnetic resonance spectroscopy (MRS) in subjects with mild cognitive impairment (MCI) and to analyze these changes with respect to the rate of cognitive decline and clinical disease progression. Fifteen subjects with MCI and 12 healthy elderly controls were investigated longitudinally (average follow-up period: 3.4 years) using absolute quantification of metabolites within the mid-parietal grey matter and the parietal white matter [N-acetylaspartate (NAA), myo-inositol, choline, creatine, glutamine)] Our main findings include that a longitudinal decline in cognitive function (particularly in memory function) within the MCI group was predicted by a decline in absolute concentrations of the metabolic markers NAA and creatine.

Evaluation of angiographic and technical aspects of carotid stenting with diffusion-weighted magnetic resonance imaging.

The detection of clinically silent ischemic lesions on postprocedural diffusion-weighted magnetic resonance images has become a preferred method for the description of embolic risks. The purpose of this single-center study was to evaluate whether diffusion-weighted imaging (DWI) could determine material related or technical risk factors of filter-protected carotid stenting. Eighty-four patients with symptomatic severe (> or = 60%) carotid artery stenoses received filter-protected carotid stenting.

Coil embolization of cavernous sinus in patients with direct and dural arteriovenous fistula.

To determine technical success and acute complication rates after endovascular coil packing of the cavernous sinus. Nineteen patients presented with either direct (13) or dural (6) arteriovenous fistula (AVF) and were treated by means of coil embolization of the cavernous sinus. The aim of treatment was complete obliteration of the fistula.

1H MR spectroscopic imaging with short and long echo time to discriminate glycine in glial tumours.

Object: To investigate glycine (Gly) concentrations in low- and high-grade gliomas based on (1)H MR spectroscopic imaging (MRSI) with short and long echo time (TE). Myoinositol (MI) and Gly appear at the same resonance frequency of 3.56 ppm, but due to strong coupling the MI signal dephases more rapidly.

Stereotactic biopsy in gliomas guided by 3-tesla 1H-chemical-shift imaging of choline.

Objective: To investigate chemical-shift imaging (CSI) to guide stereotactic biopsy of the choline 'hot spot' in cerebral lesions suggestive of low-grade glioma.

Methods: Nine patients with hyperintense lesions on T(2)-weighted images of standard magnetic resonance imaging without contrast enhancement underwent advanced magnetic resonance studies. These studies included 3-dimensional T(1)-weighted sequences with contrast enhancement and 2-dimensional (1)H-CSI spectroscopy at 3 T.

Perfusion-weighted MRI to evaluate cerebral autoregulation in aneurysmal subarachnoid haemorrhage.

Introduction: The aim of this study was to evaluate autoregulatory mechanisms in different vascular territories within the first week after aneurysmal subarachnoid haemorrhage (SAH) by perfusion-weighted magnetic resonance imaging (PW-MRI). For this purpose, regional cerebral blood flow and volume (rCVF and rCBV) were measured in relation to different degrees of angiographically visible cerebral vasospasm (CVS).

Materials And Methods: In 51 SAH patients, PW-MRI and digital subtraction angiography were performed about 5 days after onset of SAH.

Prognostic value of choline and creatine in WHO grade II gliomas.

Introduction: The purpose of this study was to evaluate whether proton magnetic resonance spectroscopy ((1)H-MRS) predicts survival time, tumor progression, and malignant transformation in patients with WHO grade II gliomas.

Materials And Methods: (1)H-MRS and MR imaging (MRI) were performed before surgery in 45 patients with histologically proven WHO grade II gliomas. Metabolite concentrations of choline-containing compounds (Cho) and creatine/phosphocreatine (tCr) were normalized to contralateral brain tissue.