Sexual Dimorphism of Radiomic Features in the Brain: An Exploratory Study Using 700 μm MP2RAGE MRI at 7 T.

Objectives: The aim of this study was to determine whether MRI radiomic features of key cerebral structures differ between women and men, and whether detection of such differences depends on the image resolution.

Materials And Methods: Ultrahigh resolution (UHR) 3D MP2RAGE (magnetization-prepared 2 rapid acquisition gradient echo) T1-weighted MR images (voxel size, 0.7 × 0.

In-scanner head motion and structural covariance networks.

In-scanner head motion systematically reduces estimated regional gray matter volumes obtained from structural brain MRI. Here, we investigate how head motion affects structural covariance networks that are derived from regional gray matter volumetric estimates. We acquired motion-affected and low-motion whole brain T1-weighted MRI in 29 healthy adult subjects and estimated relative regional gray matter volumes using a voxel-based morphometry approach.

Artificial intelligence for classification of temporal lobe epilepsy with ROI-level MRI data: A worldwide ENIGMA-Epilepsy study.

Artificial intelligence has recently gained popularity across different medical fields to aid in the detection of diseases based on pathology samples or medical imaging findings. Brain magnetic resonance imaging (MRI) is a key assessment tool for patients with temporal lobe epilepsy (TLE). The role of machine learning and artificial intelligence to increase detection of brain abnormalities in TLE remains inconclusive.

Estimation of in-scanner head pose changes during structural MRI using a convolutional neural network trained on eye tracker video.

Introduction: In-scanner head motion is a common cause of reduced image quality in neuroimaging, and causes systematic brain-wide changes in cortical thickness and volumetric estimates derived from structural MRI scans. There are few widely available methods for measuring head motion during structural MRI. Here, we train a deep learning predictive model to estimate changes in head pose using video obtained from an in-scanner eye tracker during an EPI-BOLD acquisition with participants undertaking deliberate in-scanner head movements.

High resolution automated labeling of the hippocampus and amygdala using a 3D convolutional neural network trained on whole brain 700 μm isotropic 7T MP2RAGE MRI.

Image labeling using convolutional neural networks (CNNs) are a template-free alternative to traditional morphometric techniques. We trained a 3D deep CNN to label the hippocampus and amygdala on whole brain 700 μm isotropic 3D MP2RAGE MRI acquired at 7T. Manual labels of the hippocampus and amygdala were used to (i) train the predictive model and (ii) evaluate performance of the model when applied to new scans.

The ENIGMA-Epilepsy working group: Mapping disease from large data sets.

Epilepsy is a common and serious neurological disorder, with many different constituent conditions characterized by their electro clinical, imaging, and genetic features. MRI has been fundamental in advancing our understanding of brain processes in the epilepsies. Smaller-scale studies have identified many interesting imaging phenomena, with implications both for understanding pathophysiology and improving clinical care.

Standardized Brain MRI Acquisition Protocols Improve Statistical Power in Multicenter Quantitative Morphometry Studies.

Background And Purpose: In this study, we used power analysis to calculate required sample sizes to detect group-level changes in quantitative neuroanatomical estimates derived from MRI scans obtained from multiple imaging centers. Sample size estimates were derived from (i) standardized 3T image acquisition protocols and (ii) nonstandardized clinically acquired images obtained at both 1.5 and 3T as part of the multicenter Human Epilepsy Project.

Hippocampal volumetric integrity in mesial temporal lobe epilepsy: A fast novel method for analysis of structural MRI.

Objective: We investigate whether a rapid and novel automated MRI processing technique for assessing hippocampal volumetric integrity (HVI) can be used to identify hippocampal sclerosis (HS) in patients with mesial temporal lobe epilepsy (mTLE) and determine its performance relative to hippocampal volumetry (HV) and visual inspection.

Methods: We applied the HVI technique to T1-weighted brain images from healthy control (n = 35), mTLE (n = 29), non-HS temporal lobe epilepsy (TLE, n = 44), and extratemporal focal epilepsy (EXTLE, n = 25) subjects imaged using a standardized epilepsy research imaging protocol and on non-standardized clinically acquired images from mTLE subjects (n = 40) to investigate if the technique is translatable to clinical practice. Performance of HVI, HV, and visual inspection was assessed using receiver operating characteristic (ROC) analysis.

Whole brain neuronal abnormalities in focal epilepsy quantified with proton MR spectroscopy.

Objective: To test the hypothesis that localization-related epilepsy is associated with widespread neuronal dysfunction beyond the ictal focus, reflected by a decrease in patients' global concentration of their proton MR spectroscopy (H-MRS) observed marker, N-acetyl-aspartate (NAA).

Methods: Thirteen patients with localization-related epilepsy (7 men, 6 women) 40±13 (mean±standard-deviation)years old, 8.3±13.

NAPR: a Cloud-Based Framework for Neuroanatomical Age Prediction.

The availability of cloud computing services has enabled the widespread adoption of the "software as a service" (SaaS) approach for software distribution, which utilizes network-based access to applications running on centralized servers. In this paper we apply the SaaS approach to neuroimaging-based age prediction. Our system, named "NAPR" (Neuroanatomical Age Prediction using R), provides access to predictive modeling software running on a persistent cloud-based Amazon Web Services (AWS) compute instance.

Structural MRI markers of brain aging early after ischemic stroke.

Objective: To examine associations between ischemic stroke, vascular risk factors, and MRI markers of brain aging.

Methods: Eighty-one patients (mean age 67.5 ± 13.

Structural brain changes in medically refractory focal epilepsy resemble premature brain aging.

Objective: We used whole brain T1-weighted MRI to estimate the age of individuals with medically refractory focal epilepsy, and compared with individuals with newly diagnosed focal epilepsy and healthy controls. The difference between neuroanatomical age and chronological age was compared between the three groups.

Methods: Neuroanatomical age was estimated using a machine learning-based method that was trained using structural MRI scans from a large independent healthy control sample (N=2001).

Motion and morphometry in clinical and nonclinical populations.

Introduction: The relationship between participant motion, demographic variables and MRI-derived morphometric estimates was investigated in autism spectrum disorder (ASD), attention deficit hyperactivity disorder (ADHD), schizophrenia and healthy controls. Participant motion was estimated using resting state fMRI and used as a proxy measure for motion during T1w MRI acquired in the same session. Analyses were carried out in scans qualitatively assessed as free from motion-related artifact.

Periventricular white matter abnormalities and restricted repetitive behavior in autism spectrum disorder.

Malformations of cortical development are found at higher rates in autism spectrum disorder (ASD) than in healthy controls on postmortem neuropathological evaluation but are more variably observed on visual review of in-vivo MRI brain scans. This may be due to the visually elusive nature of many malformations on MRI. Here, we utilize a quantitative approach to determine whether a volumetric measure of heterotopic gray matter in the white matter is elevated in people with ASD, relative to typically developing controls (TDC).

Pooling Morphometric Estimates: A Statistical Equivalence Approach.

Changes in hardware or image-processing settings are a common issue for large multicenter studies. To pool MRI data acquired under these changed conditions, it is necessary to demonstrate that the changes do not affect MRI-based measurements. In these circumstances, classical inference testing is inappropriate because it is designed to detect differences, not prove similarity.

The corpus callosum and recovery of working memory after epilepsy surgery.

Objective: For patients with medically intractable focal epilepsy, the benefit of epilepsy surgery must be weighed against the risk of cognitive decline. Clinical factors such as age and presurgical cognitive level partially predict cognitive outcome; yet, little is known about the role of cross-hemispheric white matter pathways in supporting postsurgical recovery of cognitive function. The purpose of this study is to determine whether the presurgical corpus callosum (CC) midsagittal area is associated with pre- to postsurgical change following epilepsy surgery.

Quantitative assessment of corpus callosum morphology in periventricular nodular heterotopia.

We investigated systematic differences in corpus callosum morphology in periventricular nodular heterotopia (PVNH). Differences in corpus callosum mid-sagittal area and subregional area changes were measured using an automated software-based method. Heterotopic gray matter deposits were automatically labeled and compared with corpus callosum changes.

Regional brain volumes and cognition in childhood epilepsy: does size really matter?

Purpose: Recent studies have correlated neurocognitive function and regional brain volumes in children with epilepsy. We tested whether brain volume differences between children with and without epilepsy explained differences in neurocognitive function.

Methods: The study sample included 108 individuals with uncomplicated non-syndromic epilepsy (NSE) and 36 healthy age- and gender-matched controls.

Etiology of hippocampal sclerosis: evidence for a predisposing familial morphologic anomaly.

Objective: We sought evidence of a hereditary component for hippocampal sclerosis (HS) by determining whether close relatives of probands with temporal lobe epilepsy (TLE) with HS also had asymptomatic HS or subtle variation in hippocampal morphology.

Methods: First-degree relatives from 15 families in which probands had TLE with HS and 32 age- and sex-matched controls were included in the study. Left and right hippocampal volumes and T2 relaxometry were measured using 3-tesla MRI.

Sodium valproate use is associated with reduced parietal lobe thickness and brain volume.

Objective: We hypothesized that total brain volume, white matter volume, and lobar cortical thickness would be different in epilepsy patients. We studied valproate relative to nonvalproate by using patients with epilepsy and healthy controls.

Methods: Patients with focal intractable epilepsy from a tertiary epilepsy center were the primary group for analysis.