Effect of Zolpidem in the Aftermath of Traumatic Brain Injury: An MEG Study.

In the past two decades, many studies have shown the paradoxical efficacy of zolpidem, a hypnotic used to induce sleep, in transiently alleviating various disorders of consciousness such as traumatic brain injury (TBI), dystonia, and Parkinson's disease. The mechanism of action of this effect of zolpidem is of great research interest. In this case study, we use magnetoencephalography (MEG) to investigate a fully conscious, ex-coma patient who suffered from neurological difficulties for a few years due to traumatic brain injury.

Frame-based stereotactic biopsy of deep-seated and midline structures in 511 procedures: feasibility, risk profile, and diagnostic yield.

Objectives: We evaluated the feasibility, safety, and diagnostic yield of frame-based stereotactic biopsies (SB) in lesions located in deep-seated and midline structures of the brain to analyze these parameters in comparison to other brain areas.

Patients And Methods: In a retrospective, tertiary care single-center analysis, we identified all patients who received SB for lesions localized in deep-seated and midline structures (corpus callosum, basal ganglia, pineal region, sella, thalamus, and brainstem) between January 1996 and June 2015. Study participants were between 1 and 82 years.

Impact of time to initiation of radiotherapy on survival after resection of newly diagnosed glioblastoma.

Background And Purpose: To evaluate the effect of timing of radiotherapy (RT) on survival in patients with newly diagnosed primary glioblastoma (GBM) treated with the same therapeutical protocol.

Materials And Methods: Patients with newly diagnosed primary GBM treated with the same therapeutical scheme between 2010 and 2015 in our institution were retrospectively reviewed. The population was trichotomized based on the time interval from surgery till initiation of RT (< 28 days, 28-33 days, > 33 days).

Combined Amino Acid Positron Emission Tomography and Advanced Magnetic Resonance Imaging in Glioma Patients.

Imaging techniques such as positron emission tomography (PET) and magnetic resonance imaging (MRI) provide valuable information about brain tumor patients. Particularly amino acid PET, advanced MRI techniques, and combinations thereof are of great interest for the non-invasive assessment of biological characteristics in patients with primary or secondary brain cancer. A methodological innovation that potentially advances research in patients with brain tumors is the increasing availability of hybrid PET/MRI systems, which enables the simultaneous acquisition of both imaging modalities.

PET imaging in patients with brain metastasis-report of the RANO/PET group.

Brain metastases (BM) from extracranial cancer are associated with significant morbidity and mortality. Effective local treatment options are stereotactic radiotherapy, including radiosurgery or fractionated external beam radiotherapy, and surgical resection. The use of systemic treatment for intracranial disease control also is improving.

Survival effects of a strategy favoring second-line multimodal treatment compared to supportive care in glioblastoma patients at first progression.

Objective: Data on the survival effects of supportive care compared to second-line multimodal treatment for glioblastoma progression are scarce. Thus, the authors assessed survival in two population-based, similar cohorts from two European university hospitals with different treatment strategies at first progression.

Methods: The authors retrospectively identified patients with newly diagnosed glioblastoma treated at two neurooncological centers.

FET PET reveals considerable spatial differences in tumour burden compared to conventional MRI in newly diagnosed glioblastoma.

Purpose: Areas of contrast enhancement (CE) on MRI are usually the target for resection or radiotherapy target volume definition in glioblastomas. However, the solid tumour mass may extend beyond areas of CE. Amino acid PET can detect parts of the tumour that show no CE.

Predicting IDH genotype in gliomas using FET PET radiomics.

Mutations in the isocitrate dehydrogenase (IDH mut) gene have gained paramount importance for the prognosis of glioma patients. To date, reliable techniques for a preoperative evaluation of IDH genotype remain scarce. Therefore, we investigated the potential of O-(2-[F]fluoroethyl)-L-tyrosine (FET) PET radiomics using textural features combined with static and dynamic parameters of FET uptake for noninvasive prediction of IDH genotype.

Combined FET PET/MRI radiomics differentiates radiation injury from recurrent brain metastasis.

Background: The aim of this study was to investigate the potential of combined textural feature analysis of contrast-enhanced MRI (CE-MRI) and static O-(2-[F]fluoroethyl)-L-tyrosine (FET) PET for the differentiation between local recurrent brain metastasis and radiation injury since CE-MRI often remains inconclusive.

Methods: Fifty-two patients with new or progressive contrast-enhancing brain lesions on MRI after radiotherapy (predominantly stereotactic radiosurgery) of brain metastases were additionally investigated using FET PET. Based on histology ( = 19) or clinicoradiological follow-up ( = 33), local recurrent brain metastases were diagnosed in 21 patients (40%) and radiation injury in 31 patients (60%).

Correlation of Dynamic O-(2-[F]Fluoroethyl)-L-Tyrosine Positron Emission Tomography, Conventional Magnetic Resonance Imaging, and Whole-Brain Histopathology in a Pretreated Glioblastoma: A Postmortem Study.

Objective: Amino acid positron emission tomography (PET) using O-(2-[F]fluoroethyl)-L-tyrosine (FET) provides important additional information on the extent of viable tumor tissue of glioblastoma compared with magnetic resonance imaging (MRI). Especially after radiochemotherapy, progression of contrast enhancement in MRI is equivocal and may represent either tumor progression or treatment-related changes. Here, the first case comparing postmortem whole-brain histology of a patient with pretreated glioblastoma with dynamic in vivo FET PET and MRI is presented.

Early treatment response evaluation using FET PET compared to MRI in glioblastoma patients at first progression treated with bevacizumab plus lomustine.

Background: The goal of this prospective study was to compare the value of both conventional MRI and O-(2-F-fluoroethyl)-L-tyrosine (FET) PET for response evaluation in glioblastoma patients treated with bevacizumab plus lomustine (BEV/LOM) at first progression.

Methods: After chemoradiation with concomitant and adjuvant temozolomide, 21 IDH wild-type glioblastoma patients at first progression (age range, 33-75 years; MGMT promoter unmethylated, 81%) were treated with BEV/LOM. Contrast-enhanced MRI and FET-PET scans were performed at baseline and after 8-10 weeks.

Update on amino acid PET of brain tumours.

Purpose Of Review: The aim of this study was to give an update on the emerging role of PET using radiolabelled amino acids in the diagnostic workup and management of patients with cerebral gliomas and brain metastases.

Recent Findings: Numerous studies have demonstrated the potential of PET using radiolabelled amino acids for differential diagnosis of brain tumours, delineation of tumour extent for treatment planning and biopsy guidance, differentiation between tumour progression and recurrence versus treatment-related changes, and for monitoring of therapy. The Response Assessment in Neuro-Oncology (RANO) working group - an international effort to develop new standardized response criteria for clinical trials in brain tumours - has recently recommended the use of amino acid PET imaging for brain tumour management in addition to MRI at every stage of disease.

Investigational PET tracers for high-grade gliomas.

High-grade gliomas (HGGs) are the most common primary malignant tumors of the brain, with glioblastoma (GBM) constituting over 50% of all the gliomas in adults. The disease carries very high mortality, and even with optimal treatment, the median survival is 2-5 years for anaplastic tumors and 1-2 years for GBMs. Neuroimaging is critical to managing patients with HGG for diagnosis, treatment planning, response assessment, and detecting recurrent disease.

Radiomics derived from amino-acid PET and conventional MRI in patients with high-grade gliomas.

Radiomics is a technique that uses high-throughput computing to extract quantitative features from tomographic medical images such as MRI and PET that usually are beyond visual perception. Importantly, the radiomics approach can be performed using neuroimages that have already been acquired during the routine follow-up of the patients allowing an additional data evaluation at low cost. In Neuro-Oncology, these features can potentially be used for differential diagnosis of newly diagnosed cerebral lesions suggestive for brain tumors or for the prediction of response to a neurooncological treatment option.

Influence of Dexamethasone on O-(2-[F]-Fluoroethyl)-L-Tyrosine Uptake in the Human Brain and Quantification of Tumor Uptake.

Purpose: O-(2-[F]fluoroethyl)-L-tyrosine ([F]FET) is an established positron emission tomography (PET) tracer for brain tumor imaging. This study explores the influence of dexamethasone therapy on [F]FET uptake in the normal brain and its influence on the maximum and mean tumor-to-brain ratio (TBR).

Procedures: [F]FET PET scans of 160 brain tumor patients were evaluated (80 dexamethasone treated, 80 untreated; each group with 40 men/40 women).

Functional magnetic resonance imaging in glioma patients: from clinical applications to future perspectives.

Functional magnetic resonance imaging (fMRI) allows the non-invasive assessment of human brain activity in vivo. In glioma patients, fMRI is frequently used to determine the individual functional anatomy of the motor and language network in a presurgical setting to optimize surgical procedures and prevent extensive damage to functionally eloquent areas. Novel developments based on resting-state fMRI may help to improve presurgical planning for patients which are unable to perform structured tasks and might extend presurgical mapping to include additional functional networks.

The role of amino-acid PET in the light of the new WHO classification 2016 for brain tumors.

Since its introduction in 2016, the revision of the World Health Organization (WHO) classification of central nervous system tumors has already changed the diagnostic and therapeutic approach in glial tumors. Blurring the lines between entities formerly labelled as "high-grade" or "low-grade", molecular markers define distinct biological subtypes with different clinical course. This new classification raises the demand for non-invasive imaging methods focusing on depicting metabolic processes.

Investigation of cis-4-[F]Fluoro-D-Proline Uptake in Human Brain Tumors After Multimodal Treatment.

Purpose: Cis-4-[F]fluoro-D-proline (D-cis-[F]FPro) has been shown to pass the intact blood-brain barrier and to accumulate in areas of secondary neurodegeneration and necrosis in the rat brain while uptake in experimental brain tumors is low. This pilot study explores the uptake behavior of D-cis-[F]FPro in human brain tumors after multimodal treatment.

Procedures: In a prospective study, 27 patients with suspected recurrent brain tumor after treatment with surgery, radiotherapy, and/or chemotherapy (SRC) were investigated by dynamic positron emission tomography (PET) using D-cis-[F]FPro (22 high-grade gliomas, one unspecified glioma, and 4 metastases).

Hybrid MR-PET of brain tumours using amino acid PET and chemical exchange saturation transfer MRI.

Purpose: PET using radiolabelled amino acids has become a promising tool in the diagnostics of gliomas and brain metastasis. Current research is focused on the evaluation of amide proton transfer (APT) chemical exchange saturation transfer (CEST) MR imaging for brain tumour imaging. In this hybrid MR-PET study, brain tumours were compared using 3D data derived from APT-CEST MRI and amino acid PET using O-(2-F-fluoroethyl)-L-tyrosine (F-FET).

Clinical routine assessment of palliative care symptoms and concerns and caregiver burden in glioblastoma patients: an explorative field study.

The implementation of self-reported outcome measurements into clinical routine was tested to help facilitate early access to palliative care (PC) for glioblastoma (GBM)-patients. Measures detail PC symptoms and concerns and caregiver burden. Between January 2014 and December 2016, a total of 337 GBM-patients were discussed during meetings of the neuro-oncology tumor board to examine further treatment options.

AIDS-Related Central Nervous System Toxoplasmosis With Increased 18F-Fluoroethyl-L-Tyrosine Amino Acid PET Uptake Due to LAT1/2 Expression of Inflammatory Cells.

We report the case of a 40-year-old woman with a progressive right-sided hemiparesis. Standard MRI revealed a contrast-enhancing brain lesion within the left basal ganglia. Ffluoroethyl-L-tyrosine (F-FET) PET showed a distinct tracer uptake (lesion-to-brain ratio [LBR]: LBRmax = 2.

Static and dynamic F-FET PET for the characterization of gliomas defined by IDH and 1p/19q status.

Purpose: The molecular features isocitrate dehydrogenase (IDH) mutation and 1p/19q co-deletion have gained major importance for both glioma typing and prognosis and have, therefore, been integrated in the World Health Organization (WHO) classification in 2016. The aim of this study was to characterize static and dynamic O-(2-F-fluoroethyl)-L-tyrosine (F-FET) PET parameters in gliomas with or without IDH mutation or 1p/19q co-deletion.

Methods: Ninety patients with newly diagnosed and untreated gliomas with a static and dynamic F-FET PET scan prior to evaluation of tumor tissue according to the 2016 WHO classification were identified retrospectively.

Pseudoprogression after glioma therapy: an update.

Initial diagnostics and follow-up of gliomas is usually based on contrast-enhanced MRI. However, the capacity of standard MRI to differentiate neoplastic tissue from posttherapeutic effects such as pseudoprogression is limited. Advanced neuroimaging methods may provide relevant additional information, which allow for a more accurate diagnosis especially in clinically equivocal situations.