Pseudoprogression in GBM versus true progression in patients with glioblastoma: A multiapproach analysis.

Background And Purpose: To investigate the feasibility of using a multiapproach analysis combining clinical data, diffusion- and perfusion-weighted imaging, and 3D magnetic resonance spectroscopic imaging to distinguish true tumor progression (TP) from pseudoprogression (PSP) in patients with glioblastoma.

Materials And Methods: Progression was suspected within 6 months of radiotherapy in 46 of the 180 patients included in the Phase-III SpectroGlio trial (NCT01507506). Choline/creatine (Cho/Cr), choline/N-acetyl aspartate (Cho/NAA) and lactate/N-acetyl aspartate (Lac/NAA) ratios were extracted.

Long-term follow-up of an overexposure radiation incident in a cohort treated with linear accelerator-based stereotactic radiosurgery for intracranial arteriovenous malformations.

Objective: Dosimetric radiosurgery incidents are rare and probably insufficiently reported in scientific publications. After a long follow-up (FU), the authors studied the outcomes of patients treated with overexposure radiation for arteriovenous malformation (AVM) administered via stereotactic radiosurgery (SRS) at their department.

Methods: Between May 2006 and June 2007, 22 patients were treated for AVM with SRS.

Local neuronal excitation and global inhibition during epileptic fast ripples in humans.

Understanding the neuronal basis of epileptic activity is a major challenge in neurology. Cellular integration into larger scale networks is all the more challenging. In the local field potential, interictal epileptic discharges can be associated with fast ripples (200-600 Hz), which are a promising marker of the epileptogenic zone.

Glioblastoma Stem-like Cell Detection Using Perfusion and Diffusion MRI.

Purpose: With current gold standard treatment, which associates maximum safe surgery and chemo-radiation, the large majority of glioblastoma patients relapse within a year in the peritumoral non contrast-enhanced region (NCE). A subpopulation of glioblastoma stem-like cells (GSC) are known to be particularly radio-resistant and aggressive, and are thus suspected to be the cause of these relapses. Previous studies have shown that their distribution is heterogeneous in the NCE compartment, but no study exists on the sensitivity of medical imaging for localizing these cells.

Variability of Intraoperative Electrostimulation Parameters in Conscious Individuals: Language Fasciculi.

Objective: The authors analyzed the current-intensity thresholds for electrostimulation of language fasciculi and the possible consequences of threshold variability on brain mapping.

Methods: A prospective protocol of subcortical electrostimulation was used in 50 patients undergoing brain mapping, directly stimulating presumed language fasciculi identified by diffusion tensor imaging.

Results: The stimulation-intensity thresholds for identification of language fasciculi varied among patients (mean minimum current intensity of 4.

Reduced Regional Cerebral Blood Flow Measured by Tc-Hexamethyl Propylene Amine Oxime Single-Photon Emission Computed Tomography in Microgravity Simulated by 5-Day Dry Immersion.

Microgravity induces a cephalad fluid shift that is responsible for cephalic venous stasis that may increase intracranial pressure (ICP) in astronauts. However, the effects of microgravity on regional cerebral blood flow (rCBF) are not known. We therefore investigated changes in rCBF in a 5-day dry immersion (DI) model.

Quality control of 3D MRSI data in glioblastoma: Can we do without the experts?

Purpose: Proton magnetic resonance spectroscopic imaging (1H MRSI) is a noninvasive technique for assessing tumor metabolism. Manual inspection is still the gold standard for quality control (QC) of spectra, but it is both time-consuming and subjective. The aim of the present study was to assess automatic QC of glioblastoma MRSI data using random forest analysis.

Iron distribution in the lentiform nucleus: A post-mortem MRI and histology study.

Iron plays an important role in many neurobiological processes, especially in the basal ganglia, the brain structures with the highest concentration. Composed of the pallidum and putamen, the lentiform nucleus plays a key role in the basal ganglia circuitry. With MRI advances, iron-based sequences such as R2* and quantitative susceptibility mapping (QSM) are now available for detecting and quantifying iron in different brain structures.

Functional and Structural Integrity of Frontoparietal Connectivity in Traumatic and Anoxic Coma.

Objectives: Recovery from coma might critically depend on the structural and functional integrity of frontoparietal networks. We aimed to measure this integrity in traumatic brain injury and anoxo-ischemic (cardiac arrest) coma patients by using an original multimodal MRI protocol.

Design: Prospective cohort study.

Recording local field potential and neuronal activity with tetrodes in epileptic patients.

Background: Recordings with tetrodes have proven to be more effective in isolating single neuron spiking activity than with single microwires. However, tetrodes have never been used in humans. We report on the characteristics, safety, compatibility with clinical intracranial recordings in epileptic patients, and performance, of a new type of hybrid electrode equipped with tetrodes.

Safety and Effectiveness of Neuro-thrombectomy on Single compared to Biplane Angiography Systems.

An increasing number of centers not necessarily equipped with biplane (BP) angiosuites are performing mechanical thrombectomy (MT) in acute ischemic stroke patients. We assessed whether MT performed on single-plane (SP) is equivalent in terms of safety, effectiveness, radiation and contrast agent exposure. Consecutive patients treated by MT in four high volume centers between January 2014 and May 2017 were included.

A Fast Visual Recognition Memory System in Humans Identified Using Intracerebral ERP.

One key item of information retrieved when surveying our visual world is whether or not objects are familiar. However, there is no consensus on the respective roles of medial temporal lobe structures, particularly the perirhinal cortex (PRC) and hippocampus. We considered whether the PRC could support a fast recognition memory system independently from the hippocampus.

Proposed achievable levels of dose and impact of dose-reduction systems for thrombectomy in acute ischemic stroke: an international, multicentric, retrospective study in 1096 patients.

Background: International dose reference levels are lacking for mechanical thrombectomy in acute ischemic stroke patients with large vessel occlusions. We studied whether radiation dose-reduction systems (RDS) could effectively reduce exposure and propose achievable levels.

Materials And Methods: We retrospectively included consecutive patients treated with thrombectomy on a biplane angiography system (BP) in five international, high-volume centers between January 2014 and May 2017.

Topological disintegration of resting state functional connectomes in coma.

Graph theory has been playing an increasingly important role in understanding the organizational properties of brain networks, subsequently providing new tools for the search of neural correlates of consciousness, particularly in the context of patients recovering from severe brain injury. However, this approach is not without challenges, as it usually relies on arbitrarily fixing a threshold in order to retain the strongest connections proportionally equal across subjects. This method increases the comparability between individuals or groups but it risks the inclusion of false positive and therefore spurious connections, especially in the context of brain disorders.

Neuronal spiking activity highlights a gradient of epileptogenicity in human tuberous sclerosis lesions.

Objective: The mechanisms underlying epileptogenicity in tuberous sclerosis complex (TSC) are poorly understood.

Methods: We analysed neuronal spiking activity (84 neurons), fast ripples (FRs), local field potentials and intracranial electroencephalogram during interictal epileptiform discharges (IEDs) in the tuber and perituber of a patient using novel hybrid electrodes equipped with tetrodes.

Results: IEDs were recorded in the tuber and perituber.

Dedicated Linear Accelerator Radiosurgery for Classic Trigeminal Neuralgia: A Single-Center Experience with Long-Term Follow-Up.

Background: During the past decades, stereotactic radiosurgery, and Gamma Knife in particular, has proved its safety and efficacy for drug-resistant classic trigeminal neuralgia. However, few large series exist using linear accelerator (LINAC) reporting long-term follow-up.

Methods: Between 2006 and 2015, 301 patients were treated by LINAC at our institution.

Imaging grafted cells with [18F]FHBG using an optimized HSV1-TK mammalian expression vector in a brain injury rodent model.

Introduction: Cell transplantation is an innovative therapeutic approach after brain injury to compensate for tissue damage. To have real-time longitudinal monitoring of intracerebrally grafted cells, we explored the feasibility of a molecular imaging approach using thymidine kinase HSV1-TK gene encoding and [18F]FHBG as a reporter probe to image enzyme expression.

Methods: A stable neuronal cell line expressing HSV1-TK was developed with an optimised mammalian expression vector to ensure long-term transgene expression.

Response Assessment in Neuro-Oncology criteria, contrast enhancement and perfusion MRI for assessing progression in glioblastoma.

Purpose: The purpose of the study was to evaluate Response Assessment in Neuro-Oncology (RANO) criteria in glioblastoma multiforme (GBM), with respect to the Macdonald criteria and changes in contrast-enhancement (CE) volume. Related variations in relative cerebral blood volume (rCBV) were investigated.

Methods: Forty-three patients diagnosed between 2006 and 2010 were included.

Familiarity and recollection vs representational models of medial temporal lobe structures: A single-case study.

Although it is known that medial temporal lobe (MTL) structures support declarative memory, the fact these structures have different architectonics and circuitry suggests they may also play different functional roles. Selective lesions of MTL structures offer an opportunity to understand these roles. We report, in this study, on JMG, a patient who presents highly unusual lesions that completely affected all MTL structures except for the right hippocampus and parts of neighbouring medial parahippocampal cortex.

Do perfusion and diffusion MRI predict glioblastoma relapse sites following chemoradiation?

To assess the value of T2* dynamic-susceptibility contrast MRI (DSC-MRI) and diffusion-weighted imaging (DWI) to predict the glioblastoma relapse sites after chemoradiation. From a cohort of 44 patients, primarily treated with radiotherapy (60 Gy) and concomitant temozolomide for glioblastoma, who were included in the reference arm of a prospective clinical trial (NCT01507506), 15 patients relapsed and their imaging data were analyzed. All patients underwent anatomical MRI, DSC-MRI and DWI before radiotherapy and every 2 months thereafter until relapse.