Normal Brain Magnetic Resonance Research Articles

Pediatric reference values of anterior visual pathway structures measured with axis-correction on high-resolution 3D T2 fast spin echo sequences

BackgroundThe size of the anterior visual pathway (AVP) structures is affected by patient age and pathology. Normative data is useful when determining whether pathology is present. AVP structures do not respect the standard planes of magnetic resonance (MR) imaging. The aim of this study was to produce normative age-related and axis-corrected data of the AVP structures using multiplanar reformation (MPR) of high-resolution 3D T2-weighted fast spin echo (3D T2w FSE) images.MethodsFor each patient 32 measurements of AVP structures were obtained in 145 children (2 months - 18 years) with normal brain MR studies on high-resolution 3D T2w FSE images adjusted to the axis of each AVP structure. Descriptive statistics were calculated for different age classes and growth models were fitted to the data and assessed for their performance to create a formal statistical model that allows inference beyond the sample.ResultsDescriptive statistics were compiled in a reference table and prediction plots in relation to age, height, and body surface area (BSA) were obtained from the best overall performing statistical model, also taking field strength (1.5 vs. 3 T) into account. Intraclass correlation coefficient values were calculated for all variables ranging from 0.474 to 0.967, the most reliable being the transverse diameter of the globe, the maximum diameter of the retrobulbar nerve sheath, the intracranial segment of the optic nerve and the transverse diameter of the chiasm. The maximum retrobulbar diameter of the optic nerve sheath and the lateral superoinferior diameter of the chiasm showed no statistically significant change with age.ConclusionDetailed charts of reference values for AVP structures as well as prediction plots in relation to age, height and BSA were established using axis-corrected measurements from the MPR of high-resolution 3D T2w FSE images. Furthermore, an Excel spreadsheet that allows users to calculate normative values for the 9 AVP structures of key interest is provided as supplementary material.

Long-term-video monitoring EEG and 18F-FDG-PET are useful tools to detect residual disease activity in anti-LGI1-Abs encephalitis: A case report

BackgroundThe use of CD20-depleting monoclonal antibodies has shown to improve the long-term outcome of patients with anti-leucine-rich glioma-inactivated protein 1 antibodies (anti-LGI1-Abs) encephalitis after first-line immunotherapy, but currently predictive markers of treatment response and disease activity are lacking.Case presentationA 75-year-old man presented cognitive impairment and faciobrachial dystonic seizures (FBDS), with mild abnormalities at electroencephalography (EEG), normal brain magnetic resonance and cerebrospinal fluid (CSF) analysis. Anti-LGI1-Abs were detected in serum and CSF, and corticosteroids and intravenous immunoglobulins were administered. Despite partial cognitive improvement, 18F-fluoridesoxyglucose-positron emission tomography (18F-FDG-PET) showed the persistence of temporo-mesial hypermetabolism, and FBDS were still detected by long-term monitoring video EEG (LTMV EEG). Rituximab was therefore administered with FBDS disappearance, further cognitive improvement, and resolution of 18F-FDG-PET temporo-mesial hypermetabolism.ConclusionsOur experience supports the use of 18F-FDG-PET and LTMVEEG as useful tools to measure disease activity, evaluate treatment response and guide therapeutic decisions in the long-term management of anti-LGI1-antibody encephalitis.

Detection rate of MR myelography without intrathecal gadolinium in patients with newly diagnosed spontaneous intracranial hypotension

To evaluate the detection rate of magnetic resonance (MR) myelography without intrathecal gadolinium for cerebrospinal fluid (CSF) leakage in patients with newly diagnosed spontaneous intracranial hypotension (SIH) and to validate a published scoring system for predicting CSF leakage. This retrospective, observational, single-institution study included patients with newly diagnosed SIH between March 2015 and April 2021. Patients were included if they (a) had newly diagnosed SIH and (b) underwent initial brain MR imaging and preprocedural MR myelography with two- and three-dimensional turbo spin-echo sequences. Patients who underwent spine surgery or procedures including epidural injection and acupuncture were excluded. The detection rate was defined as the proportion of patients with a true-positive MR myelography result among all patients with confirmed CSF leakage. The interobserver agreement for the MR myelography results between two radiologists was analysed using weighted kappa statistics. A total of 136 patients (mean age, 48 years; 70 women) with suspected SIH were included. Of these patients, 120 (88%, 120/136) were confirmed to have CSF leakage. Of the patients with confirmed CSF leakage, 90 (75%, 90/120) had epidural fluid collection. The detection rate of MR myelography for CSF leakage was 88% (105/120). The interobserver agreement between the two readers for detecting CSF leakage (κ=0.76) or epidural fluid collection (κ=0.76) on MR myelography was high. Among 24 patients with normal brain MR imaging results, 16 had CSF leakage (67%, 16/24). Non-invasive MR myelography without intrathecal gadolinium should be considered to detect CSF leakage in patients with suspected SIH.

MR brain segmentation based on DE-ResUnet combining texture features and background knowledge

The segmentation of the brain Magnetic Resonance (MR) images plays an essential role in neuroimaging research and clinical settings. Currently, deep learning combined with prior knowledge and attention mechanism is intensively implemented to solve the brain tissue segmentation task because of its superior performance. However, there are still two problems: firstly, some prior knowledge is difficult to obtain; secondly, incorrect attention is easy to produce in self-attention mechanism. To address these two issues, a novel dual encoder residual U-Net based on texture features and background knowledge, namely DE-ResUnet, is proposed in this work. In DE-ResUnet, the dual encoders for T1-weighted image and texture features are combined to learn hidden additional information. The introduction of channel attention mechanism (CAM) into two encoder and decoder paths facilitates the model to extract more useful informative features. Moreover, we design a strengthen module to refine the coarse segmentation, which can focus on brain tissue regions guided by background knowledge. We evaluate our proposed method on BrainWeb, OASIS-1 and CANDI datasets. The experimental results show that the proposed DE-ResUnet network achieves the accurate segmentation superior to that of several state-of-the-art methods. We also evaluate DE-ResUnet on the BraTS 2020 dataset and achieve good segmentation results. These experiments demonstrate that DE-ResUnet can not only segment normal brain MR images accurately, but also locate the area of the lesion in abnormal images. Our code is freely available at https://github.com/LiangWUSDU/DE-ResUnet.

Ring chromosome 20: A further contribution to the delineation of epileptic phenotype

Introduction. Ring chromosome 20 [r(20)] syndrome is a rare genetic abnormality where two arms of the 20th chromosome fuse forming a ring chromosome, resulting in intractable epilepsy and wide range of behavioral problems and cognitive deficits. Case report. We presented four patients with r (20) syndrome diagnosed between the years 2000?2018. In all patients we analyzed clinical epilepsy features (seizure semiology, seizure frequency/drug response, the presence of nonconvulsive status epilepticus), cognitive status and the phenotype characteristics. The average age of epilepsy onset was 6 years. All four patients had nocturnal epileptic events and normal brain magnetic resonance (MR) imaging. Dysmorphism was present in two children, behavioral problems also in two children and intellectual disabilities were observed in three children. R(20) syndrome mosaicism ranged between 17% and 83% of blood lymphocytes. Conclusion. Despite the small size of our group, we think that our findings have clinical relevance. Refractory child-hood onset epilepsy and especially the occurrence of nocturnal epileptic events should help physicians to recognize this chromosomopathy. Routine karyotyping can be employed to identify the patients easily.

An automated computer-aided diagnosis system for classification of MR images using texture features and gbest-guided gravitational search algorithm

The segmentation and classification of brain magnetic resonance (MR) images are the crucial and challenging task for radiologists. The conventional methods for analyzing brain images are time-consuming and ineffective in decision-making. Thus, to overcome these limitations, this work proposes an automated and robust computer-aided diagnosis (CAD) system for accurate classification of normal and abnormal brain MR images. The proposed CAD system has the ability to assist the radiologists for diagnosis of brain MR images at an early stage of abnormality. Here, to improve the quality of images before their segmentation, contrast limited adaptive histogram equalization (CLAHE) is employed. The segmentation of the region of interest is obtained using the multilevel Otsu's thresholding algorithm. In addition, the proposed system selects the most significant and relevant features from the texture and multiresolution features. The multiresolution features are extracted using discrete wavelet transform (DWT), stationary wavelet transform (SWT), and fast discrete curvelet transform (FDCT). Moreover, the Tamura and local binary pattern (LBP) are used to extract the texture features from the images. These features are used to classify the brain MR images using feedforward neural network (FNN) classifier, where different meta-heuristic optimization algorithms, e.g., genetic algorithm (GA), particle swarm optimization (PSO), gravitational search algorithm (GSA), and gbest-guided gravitational search algorithm (GG-GSA) are employed for optimizing the weights and biases of FNN. The extensive experimental results on DS-195, DS-180, and three standard datasets show that the classification accuracy of GG-GSA based FNN classifier outperforms all mentioned meta-heuristic-based classifiers and several state-of-the-art methods.

Changes in Connectivity between Caudate and Frontal Lobe in Patient with Psychosis Induced for Cannabis - Case Report

The use of marihuana is becoming more frequent in young people, the association between psychosis and cannabis has been described, especially in young people, we present a clinical case of psychosis associated with cannabis in a young man with normal Brain Magnetic resonance, but abnormalities in tractography mainly in the connectivity between cuadate nucleus and frontal lobe.

Familial Hemiplegic Migraine with Severe Attacks: A New Report with ATP1A2 Mutation.

Introduction. Familial hemiplegic migraine (FHM) is a rare disorder characterized by migraine attacks with motor weakness during the aura phase. Mutations in CACNA1A, ATP1A2, SCN1A, and PRRT2 genes have been described. Methods. To describe a mutation in ATP1A2 gene in a FHM case with especially severe and prolonged symptomatology. Results. 22-year-old woman was admitted due to migraine-type headache and sudden onset of right-sided weakness and aphasia; she had similar episodes in her childhood. Her mother was diagnosed with hemiplegic migraine without genetic confirmation. She presented with fever, decreased consciousness, left gaze preference, mixed aphasia, right facial palsy, right hemiplegia, and left crural paresis. Computed tomography (CT) showed no lesion and CT perfusion study evidenced oligohemia in left hemisphere. A normal brain magnetic resonance (MR) was obtained. Impaired consciousness and dysphasia began to improve three days after admission and mild dysphasia and right hemiparesis lasted for 10 days. No recurrences were reported during a follow-up of two years. We identified a variant in heterozygous state in ATP1A2 gene (p.Thr364Met), pathogenic according to different prediction algorithms (SIFT, PolyPhen2, MutationTaster, and Condel). Conclusion. Prolonged and severe attacks with diffuse hypoperfusion in a FHM seemed to be specially related to ATP1A2 mutations, and p.T364M should be considered.

Classification of magnetic resonance brain images using bi-dimensional empirical mode decomposition and autoregressive model

Purpose Automated classification of brain magnetic resonance (MR) images has been an extensively researched topic in biomedical image processing. In this work, we propose a new approach for classifying normal and abnormal brain MR images using bi-dimensional empirical mode decomposition (BEMD) and autoregressive (AR) model

White matter involvement beyond the optic nerves in CRION as assessed by diffusion tensor imaging

Background: Chronic relapsing inflammatory optic neuropathy (CRION) is an inflammatory optic neuropathy, characterized by relapses and remissions in patients with normal brain and spinal magnetic resonance imaging (MRI). Discrepancy from other demyelinating diseases is important, and it is still uncertain whether CRION is restricted to the optic pathways or it affects other brain white matter (WM) structures. Objective: To assess WM structure in patients with CRION by using diffusion tensor imaging (DTI). Methods: DTI was performed in six CRION patients and six age- and sex-matched healthy controls on a 3 T scanner. Tract-based spatial statistics (TBSS) was used for voxelwise statistical analysis of DTI data. Fractional anisotropy (FA), mean diffusivity (MD), axial diffusivity (AD), radial diffusivity (RD) measures were obtained. Results: TBSS analysis revealed two different patterns of WM alterations in patients with CRION. The optic chiasm and connected structures had significantly higher FA and lower RD, AD and MD in the patients than in the healthy controls. On the other hand, anterior frontal bundles of inferior fronto-occipital tracts, left uncinate fascicule and internal capsule showed decreased FA and increased RD. No correlation was found between the clinical variables and diffusion measures. Conclusion: WM appearing normal on brain MRI shows widespread abnormalities in a cohort of CRION patients as assessed by DTI.

Spontaneous Intracranial Hypotension: Recommendations for Management

A literature search found no clinical trials or guidelines addressing the management of spontaneous intracranial hypotension (SIH). Based on the available literature and expert opinion, we have developed recommendations for the diagnosis and management of SIH. For typical cases, we recommend brain magnetic resonance (MR) imaging with gadolinium to confirm the diagnosis, and conservative measures for up to two weeks. If the patient remains symptomatic, up to three non-directed lumbar epidural blood patches (EBPs) should be considered. If these are unsuccessful, non-invasive MR myelography, radionuclide cisternography, MR myelography with intrathecal gadolinium, or computed tomography with myelography should be used to localize the leak. If the leak is localized, directed EPBs should be considered, followed by fibrin sealant or neurosurgery if necessary. Clinically atypical cases with normal brain MR imaging should be investigated to localize the leak. Directed EBPs can be used if the leak is localized; non-directed EBPs should be used only if there are indirect signs of SIH.

Sporadic hemiplegic migraine with normal imaging as the initial manifestation of CADASIL

Cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL) can be present with negative family history and, especially in younger patients, with normal brain magnetic resonance. For this reason, those CADASIL patients that present only with migraine may be misdiagnosed. In the case of migraine with motor aura, sporadic hemiplegic migraine (SHM) is one of the possible misdiagnoses. We present a case of a patient who, in the first years of her disease, met the clinical criteria for SHM. A diagnosis of CADASIL was considered only when her sister presented with headache and an unknown leukoencephalopathy. This case illustrates the need for a careful review of the clinical and family history during the follow-up of primary headaches.

Does normal fetal brain ultrasound predict normal neurodevelopmental outcome in congenital cytomegalovirus infection?

We evaluated the neuropsychological outcome of children with proven congenital cytomegalovirus (CMV) infection and normal consecutive fetal neurosonographic examinations. We retrospectively reviewed laboratory and imaging findings of children with congenital CMV infection. The study group consisted of children with a positive polymerase chain reaction (PCR) in amniotic fluid and virus isolation in urine in the first week of life, and normal fetal ultrasonographic (US) examination findings, including a normal multiplanar neurosonographic evaluation. Patients with abnormal magnetic resonance (MR) findings were not excluded. The study and control groups were evaluated for cognitive, language, and motor development at one follow-up examination conducted at 11-81 months of age. Children with congenital CMV infection and normal fetal brain findings in the US examination did not differ from the control group in terms of cognitive, language, motor, emotional-behavioral, and executive functioning. There were no differences between congenitally infected children who had a normal fetal brain MR examination and children whose fetal brain MR examination raised suspicion of a possible brain insult. Normal neurosonographic examinations during pregnancy appear to predict a normal early neuropsychological outcome in fetuses with congenital CMV infection. Outcome did not correlate with suspected abnormal white matter on fetal MR imaging.

Pathogenesis of Normal-appearing White Matter Damage in Neuromyelitis Optica: Diffusion-Tensor MR Imaging

To prospectively evaluate diffusion indexes of the corticospinal tract (CST), corpus callosum (CC), optic radiation (OR), and cingulum in patients with neuromyelitis optica (NMO) without visible lesions in the brain. All participants provided informed consent, and the study was approved by the institutional review board. Nineteen patients with NMO (one man, 18 women; mean age, 35.1 years; range, 19-55 years) with normal brain magnetic resonance (MR) imaging findings and 19 sex- and age-matched healthy control subjects were examined with diffusion-tensor MR imaging. The CST, CC, OR, and cingulum were globally and regionally analyzed by using mean diffusivity, fractional anisotropy, and primary (lambda1) and transverse (lambda23) eigenvalues. Correlations of diffusion indexes of the CST and OR with the pyramidal and visual components of the Kurtzke Functional Systems (KFS) and Expanded Disability Status Scale scores were also investigated. Student t testing and Pearson correlation were performed. As compared with values in control subjects, both global and regional analyses showed significant (P < .01) increases in mean diffusivity and lambda23 of the CST and OR but not in any of the diffusion indexes of the CC and cingulum in patients with NMO. In patients with NMO, mean diffusivity (r = 0.556, P = .013) and lambda1 (r = 0.556, P = .013) of the CST were correlated with pyramidal KFS scores, and mean diffusivity (r = 0.523, P = .022) and lambda1 (r = 0.504, P = .027) of the OR were correlated with visual KFS scores. Axonal degeneration secondary to lesions in the spinal cord and optic nerves is a cause of normal-appearing white matter damage in NMO. http://radiology.rsnajnls.org/cgi/content/full/2461062075/DC1.

Automatic anatomical brain MRI segmentation combining label propagation and decision fusion

Regions in three-dimensional magnetic resonance (MR) brain images can be classified using protocols for manually segmenting and labeling structures. For large cohorts, time and expertise requirements make this approach impractical. To achieve automation, an individual segmentation can be propagated to another individual using an anatomical correspondence estimate relating the atlas image to the target image. The accuracy of the resulting target labeling has been limited but can potentially be improved by combining multiple segmentations using decision fusion. We studied segmentation propagation and decision fusion on 30 normal brain MR images, which had been manually segmented into 67 structures. Correspondence estimates were established by nonrigid registration using free-form deformations. Both direct label propagation and an indirect approach were tested. Individual propagations showed an average similarity index (SI) of 0.754 ± 0.016 against manual segmentations. Decision fusion using 29 input segmentations increased SI to 0.836 ± 0.009. For indirect propagation of a single source via 27 intermediate images, SI was 0.779 ± 0.013. We also studied the effect of the decision fusion procedure using a numerical simulation with synthetic input data. The results helped to formulate a model that predicts the quality improvement of fused brain segmentations based on the number of individual propagated segmentations combined. We demonstrate a practicable procedure that exceeds the accuracy of previous automatic methods and can compete with manual delineations.

Diffusion-tensor MR imaging in children with developmental delay: preliminary findings.

To determine whether diffusion-tensor magnetic resonance (MR) imaging can depict abnormalities in patients with a diagnosis of developmental delay but structurally normal brain MR imaging results. Twenty pediatric patients who received a diagnosis of developmental delay underwent brain MR examinations, including diffusion-tensor MR imaging. The MR findings in these patients were compared with those in 10 age-matched neurodevelopmentally healthy children. Diffusion constant (Dav) and anisotropy were measured bilaterally in regions of interest in the centrum semiovale, corona radiata, internal capsule, corpus callosum, and subcortical white matter of the frontal and parieto-occipital lobes. By using a one-tailed Student t test in the positive direction for Dav and in the negative direction for anisotropy and P <.05 to indicate a significant difference, the Dav and anisotropy values for children with developmental delay were compared with those for children who were neurodevelopmentally healthy. The children with developmental delay had significant increases in Dav in all measured structures (P, <.001 to <.03). Significant decreases in anisotropy were detected in all white matter fiber tracts studied (P, <.001 to <.03) except the posterior limb of the internal capsule. In the children with developmental delay, diffusion-tensor MR imaging depicted decreases in anisotropy and increases in Dav in the white matter fiber tracts, which appeared to be normal at conventional MR imaging.