Clinical, radiological and molecular characterization of intramedullary astrocytomas.

Intramedullary astrocytomas (IMAs) are rare tumors, and few studies specific to the molecular alterations of IMAs have been performed. Recently, KIAA1549-BRAF fusions and the H3F3A p.K27M mutation have been described in low-grade (LG) and high-grade (HG) IMAs, respectively.

Central diabetes insipidus and pituitary stalk thickening in adults: distinction of neoplastic from non-neoplastic lesions.

Context: Association of central diabetes insipidus (CDI) and pituitary stalk thickening (PST) may have several etiologies (including malignancies) and differential diagnosis remains often difficult.

Objective: The purpose of this study was to identify which clinical, biochemical or radiological features could help clinicians to make an etiological diagnosis, especially distinguishing neoplastic from non-neoplastic pituitary stalk lesions.

Designs And Methods: We retrospectively analyzed clinical, biochemical, radiological and histological data of 38 adult patients diagnosed with CDI and PST of proven etiology.

Dopamine transporter genotype modulates brain activity during a working memory task in children with ADHD.

Dopamine active transporter gene (DAT1) is a candidate gene associated with attention-deficit/hyperactivity disorder (ADHD). The DAT1 variable number tandem repeat (VNTR)-3' polymorphism is functional and 9R carriers have been shown to produce more DAT than 10R homozygotes. We used functional magnetic resonance imaging (fMRI) to investigate the effects of this polymorphism on the neural substrates of working memory (WM) in a small but selected population of children with ADHD, naïve of any psychotropic treatment and without comorbidity.

Relationship Between White Matter Abnormalities and Neuropsychological Measures in Children With ADHD.

Using Diffusion Tensor Imaging (DTI), to investigate microstructural white matter differences between ADHD and typically developing children (TDC), and their association with inhibition and working memory performance usually impaired in ADHD. Fractional anisotropy (FA) and mean diffusivity (MD) were estimated in 36 noncomorbid children with a (4th ed., text rev.

The Neural Basis of Speech Perception through Lipreading and Manual Cues: Evidence from Deaf Native Users of Cued Speech.

We present here the first neuroimaging data for perception of Cued Speech (CS) by deaf adults who are native users of CS. CS is a visual mode of communicating a spoken language through a set of manual cues which accompany lipreading and disambiguate it. With CS, sublexical units of the oral language are conveyed clearly and completely through the visual modality without requiring hearing.

Grey matter volume differences associated with gender in children with attention-deficit/hyperactivity disorder: A voxel-based morphometry study.

Female participants have been underrepresented in previous structural magnetic resonance imaging reports on attention-deficit/hyperactivity disorder (ADHD). In this study, we used optimized voxel-based morphometry to examine grey matter volumes in a sample of 33 never-medicated children with combined-type ADHD and 27 typically developing (TD) children. We found a gender-by-diagnosis interaction effect in the ventral anterior cingulate cortex (ACC), whereby boys with ADHD exhibited reduced volumes compared with TD boys, while girls with ADHD showed increased volumes when compared with TD girls.

Grey matter volumes in treatment naïve vs. chronically treated children with attention deficit/hyperactivity disorder: a combined approach.

Psychostimulants are the first-line treatment in attention deficit/hyperactivity disorder (ADHD), but their effects on brain development remain poorly understood. In particular, previous structural magnetic resonance imaging (sMRI) studies only investigated treatment effects on grey matter (GM) volumes in selected regions of interest (ROIs). In this study, voxel-based morphometry (VBM) was used to assess medication-related GM volume differences across the entire brain.

Structural correlates of COMT Val158Met polymorphism in childhood ADHD: a voxel-based morphometry study.

Objectives: The Val158-allele of the catechol-O-methyltransferase (COMT) Val158Met (rs4680) functional polymorphism has been identified as a risk factor for antisocial behaviour in attention-deficit/hyperactivity disorder (ADHD). Here, we used voxel-based morphometry to investigate the effects of Val158Met polymorphism on grey matter (GM) volumes in a sample of 7-13-year-old children.

Methods: MRI and genotype data were obtained for 38 children with combined-type ADHD and 24 typically developing (TD) children.

Acute aseptic meningitis as the initial presentation of a macroprolactinoma.

Background: Meningitis is an uncommon complication of an untreated pituitary macroadenoma. Meningitis may occur in patients with macroadenomas who have undergone transsphenoidal surgery and radiotherapy and is usually associated with rhinorrhea. Less commonly, cerebrospinal fluid rhinorrhea has been reported as a complication of treatment of prolactinomas by dopamine agonists.

Language development at 2 years is correlated to brain microstructure in the left superior temporal gyrus at term equivalent age: a diffusion tensor imaging study.

This study aims at testing the hypothesis that neurodevelopmental abilities at age 2 years are related with local brain microstructure of preterm infants at term equivalent age. Forty-one preterm infants underwent brain MRI with diffusion tensor imaging sequences to measure mean diffusivity (MD), fractional anisotropy (FA), longitudinal and transverse diffusivity (λ// and λ[perpendicular]) at term equivalent age. Neurodevelopment was assessed at 2 years corrected age using the Bayley III scale.

Nonlinear microstructural changes in the right superior temporal sulcus and lateral occipitotemporal gyrus between 35 and 43 weeks in the preterm brain.

Using diffusion tensor imaging (DTI), we explored microstructural brain maturation in a population of 65 preterm neonates who underwent magnetic resonance imaging between 35 and 43 weeks of corrected gestational age. A voxel-based analysis approach, statistical parametric mapping (SPM8), was used to evidence the nonlinear changes with the corrected gestational age in the regional distribution of mean diffusivity (MD), fractional anisotropy (FA), longitudinal and transverse diffusivities (λ//and λ⊥). We found that FA changes nonlinearly with age around the right superior temporal sulcus and in the right lateral occipitotemporal gyrus, with FA decrease between 34 and 39 weeks followed by FA increase from 40 weeks to 43 weeks.

High levels of cellular proliferation predict pseudoprogression in glioblastoma patients.

Radiochemotherapy (RT) with concomitant followed by monthly temozolomide (TMZ) chemotherapy is the gold standard for the treatment of glioblastoma (GBM) patients. GBM patients can experience transient radiological deterioration after concurrent RT/TMZ that stabilizes or even resolves after additional cycles of adjuvant TMZ, a phenomenon defined as radiological pseudoprogression. The aim of this retrospective study was to identify a reliable marker associated with pseudoprogression processes.

Brain regional glucose uptake changes in isolated cerebellar cortical dysplasia: qualitative assessment using coregistrated FDG-PET/MRI.

We aimed to assess brain regional glucose uptake (rGlcU) changes in children with isolated cerebellar cortical dysplasia (CCD) using 18-fluoro-deoxy-glucose positron emission tomography (FDG-PET). Six children aged 9 months to 11 years at the time of diagnosis, carrying isolated CCD (with no other associated posterior fossa or supratentorial malformation) underwent a brain FDG-PET and a subsequent 3DT1-weighted MRI for coregistration. The MRIs acquired previously at the time of diagnosis were reviewed to record the cerebellar dysplastic features and classify the patients as having minor, moderate, or severe CCD.

A Monte Carlo simulation of image misalignment effects in diffusion tensor imaging.

Diffusion tensor imaging (DTI) and tractography are noninvasive MRI methods, providing an insight on microscopic structural information of anisotropic tissues in vivo. The success of this technique stems on a watchful choice of imaging parameters and post-acquisition reconstruction. In the present work, we have focused on the problem of residual linear image misalignment in the DTI data and its effects on the parameters of the diffusion tensor and fiber tracking in human brain.

Cervical vertebral artery rerouting: a technique for releasing kinks and restoring endovascular access.

Background: The endovascular treatment of intracranial aneurysms can be hampered by the tortuosity of extracranial vessels. Percutaneous or surgical vessel puncture can resolve the problem of inaccessibility.

Objective: We describe rerouting of a kinked vertebral artery (VA) to restore transfemoral endovascular access to an aneurysm.

Preliminary personal experiences with the application of near-infrared indocyanine green videoangiography in extracranial vertebral artery surgery.

Introduction: We evaluated the feasibility, usefulness, and limitations of near-infrared indocyanine green (ICG) videoangiography during procedures involving the extracranial vertebral artery (VA).

Methods: Nine patients (2 women, 7 men; mean age, 55 years) were evaluated at 2 neurosurgical centers. Near-infrared ICG videoangiography was applied during transposition and rerouting of the first segment of VA (V1; n = 6) and during resection of neurinomas near the second (V2; n = 1) and third (V3; n = 2) segments of VA.

Selective embolization of unruptured intracranial aneurysms is associated with low retreatment rate.

Introduction: To report long-term imaging findings of 101 patients with 129 unruptured intracranial aneurysms (UIA) treated by embolization.

Methods: A retrospective review of our prospectively maintained database identified all patients with an UIA treated by embolization with coils only and with a minimal 12-month imaging follow-up. The clinical charts, procedural data, and angiographic results were reviewed.

Stenting is improving and stabilizing anatomical results of coiled intracranial aneurysms.

Introduction: Stent-assisted coiling (SAC) is an alternative to surgical clipping for the treatment of wide-necked intracranial aneurysms (IA). However, little information is available concerning the long-term results of this treatment. The aim of this study was to report the long-term clinical and anatomical findings in 32 patients with 34 wide-necked IA treated by SAC.

Leptomeningeal dissemination of low-grade intramedullary gliomas: about one case and review.

Leptomeningeal (LM) dissemination arises rarely in patients with low-grade gliomas. Few cases of LM dissemination of spinal cord low-grade gliomas have been reported in children. Here, we report a case of an intramedullary spinal cord low-grade glioma occurring in an adult presenting by LM dissemination.

Endovascular treatment of proximal anterior cerebral artery aneurysms.

Introduction: Aneurysms of the proximal segment of the anterior cerebral artery (A1A) are rare and challenging to treat. No information is available regarding their management by endovascular approach. The aim of this study was to report our experience with endovascular treatment (EVT) of A1As.

Is digital substraction angiography still needed for the follow-up of intracranial aneurysms treated by embolisation with detachable coils?

Introduction: Follow-up of intracranial aneurysms treated by embolisation with detachable coils is mandatory to detect a possible recanalisation. The aim of this study was to compare contrast-enhanced magnetic resonance angiography (CE-MRA) with digital substraction angiography (DSA) used to detect aneurysm recanalisation to determine if DSA is still needed during follow-up.

Materials And Methods: From May 2006 to May 2007, 55 patients with 67 aneurysms were treated by endosaccular coiling with (n = 9) or without (n = 58) an adjunctive stent.

Combination of functional magnetic resonance imaging-guided neuronavigation and intraoperative cortical brain mapping improves targeting of motor cortex stimulation in neuropathic pain.

Objective: To evaluate, regardless of the clinical results, the contribution of combining functional magnetic resonance imaging (fMRI) with intraoperative cortical brain mapping (iCM) as functional targeting methods for epidural chronic motor cortex stimulation (MCS) in refractory neuropathic pain.

Methods: Eighteen neuropathic pain patients (central stroke in six; trigeminal neuropathy in six; syrinx or amputation in six) who underwent operations for epidural MCS were studied with preoperative fMRI and iCM. fMRI investigated motor tasks of hands (as well as foot and tongue, when painful).