Posterior Limb Of Internal Capsule Research Articles

Sudden jerky head movement in hypoglycemia

Hypoglycemia is associated with adrenergic and various neurological symptoms including hemiparesis. Though not common, movement disorders such as chorea and ballism have been reported in hypoglycemia. This case was of an elderly lady, a known diabetic, who developed two episodes of hemiparesis and single episode of jerky head movement with preserved sensorium lasting for few seconds, associated with hypoglycemia on different occasions, 1 week after increasing the dosage of oral hypoglycemic agent with complete recovery each time with correction of sugar levels. Magnetic resonance imaging showed transient bilateral diffusion restriction in posterior limb of internal capsule.

Capabilities of voxel based morphometry and diffusion tensor imaging in diagnostics of bilateral spastic forms of cerebral palsy

The aim of the study was to determine the capabilities of magnetic resonance morphometry and diffusion tensor imaging in the diagnosis of bilateral spastic forms of cerebral palsy in children. The main groups were 33 children aged from 1 year to 4 years 5 months. with bilateral spastic forms of cerebral palsy, the comparison group – 11 children who did not have movement disorders. The patients underwent magnetic resonance morphometry, diffusion tensor imaging. A comparison was made between the volumes of brain structures and diffusion values between groups. Significant differences (p < 0,05) were found in the volumes of the right lateral, 3rd ventricles, white matter, thalamuses, globus pallidus, putamen, hippocampus. Significant differences (p < 0,05) in diffusion values in the thalamuses and in the posterior limb of internal capsules were also identified. The correlation of the identified changes with the clinic of the disease was demonstrated. The obtained data demonstrate wide possibilities and high diagnostic value in the detection of bilateral spastic forms of cerebral palsy in children.

Neurotization Actuating Flexion and Extension Effectively Alleviates the Hindlimb Hemiplegia Caused by Hemorrhagic Stroke

Background: Central hemiplegia led by hypertensive intracerebral hemorrhage(HICH) is prevalent, devastating, and currently unable to intervene satisfactorily. Here,to move toward the clinic,we explored whether contralateral L4 nerve transfer,centralizing at flexion and extension, reanimates fine motor function for hemiplegic hindlimbs after HICH. Methods: Eligible rat models were manufactured by injecting autologous vein blood into the posterior limb of internal capsule (PLIC).Thirty rats were randomized into three groups.Rats in group A underwent sham operation(i.e.,exposure of bi-L4 roots without severance) after injection of saline. Rats in group B and group C were infused equal blood followed by bilateral L4 nerve roots transection and contralateral L4 nerve transfer, respectively. Behavioural, ultrastructural, immunofluorescent, and electromyographic assessments were applied at a scheduled timepoint in our study. fMRI was used as localization of PLIC impact. Findings: Through neurotization, skilled motion produced by dexterous flexion and extension in major joints (hip, knee, and ankle) of the paralyzed hindlimb recovered more sharply in group C than in group B (P<0.001), with BBB scores increasing accordingly. Reinnervated potentials were significantly detected for denervated flexors or extensors in group C, compared with group B(P<0.05). Simultaneously, detached fore-hindpaw prints were converted to an approximate superposition in a temporally-improved fashion. Histological and ultra-microstructural assessments revealed that at the anastomosis point, numerous axons were generated, realigned, and remyelinated over time. Interpretation: Neurotization involving contralateral L4 transfer activates robust flexion and extension, and efficaciously repairs the hemiplegic hindlimb after HICH. Funding Statement: This study was supported by grants from the National Natural Science Foundation of China (No. 81171147), “Key Medical Talents of Qiangwei Project” Research Foundation of Health Department of Jiangsu Province (No. ZDRCA2016010), “Xingwei Project” Key Personal Medical Research Foundation of Health Department of Jiangsu Province (No. RC201156), Jiangsu Province’s Natural Science Foundation (BK20171064), Research Foundation of Jiangsu Provincial Medical Youth Talent, the Project of Invigorating Health Care through Science, Technology and Education (QNRC2016858). Jiangsu Province’s Key Discipline of Medicine (No. XK201117) and the Priority Academic Program Development of Jiangsu Higher Education Institutions (PAPD). Declaration of Interests: All authors report no disclosures relevant to the manuscript, and claim no conflict of interests. Ethics Approval Statement: Animal experiments were conducted in accordance with the principles and procedures outlined in the NIH Guide for the Care and Use of Laboratory Animals (National Academies Press, 2011). Procedures concerning animals were approved by the Institutional Animal Care and Use Committee at Nanjing Medical University (Nanjing,Jiangsu,China;approval no. IACUC-1906009).

Whole-Brain Functional and Diffusion Tensor MRI in Human Participants with Metallic Orthodontic Braces.

Background MRI performed with echo-planar imaging (EPI) sequences is sensitive to susceptibility artifacts in the presence of metallic objects, which presents a substantial barrier for performing functional MRI and diffusion tensor imaging (DTI) in patients with metallic orthodontic material and other head implants. Purpose To evaluate the ability to reduce susceptibility artifacts in healthy human participants wearing metallic orthodontic braces for two alternative approaches: T2-prepared functional MRI and diffusion-prepared DTI with three-dimensional fast gradient-echo readout. Materials and Methods In this prospective study conducted from February to September 2018, T2-prepared functional MRI and diffusion-prepared DTI were performed in healthy human participants. Removable dental braces with bonding trays were used so that MRI could be performed with braces and without braces in the same participants. Results were evaluated in regions with strong (EPI dropout regions for functional MRI and the inferior fronto-occipital fasciculus for DTI) and minimal (motor cortex for functional MRI and the posterior limb of internal capsule for DTI) susceptibility artifacts. Signal-to-noise ratio (SNR), contrast-to-noise ratio for functional MRI, apparent diffusion coefficient and fractional anisotropy for DTI, and degree of distortion (quantified with the Jaccard index, which measures the similarity of geometric shapes) were compared in regions with strong or minimal susceptibility effects between the current standard EPI sequences and the proposed alternatives by using paired t test. Results Six participants were evaluated (mean age ± standard deviation, 40 years ± 6; three women). In brain regions with strong susceptibility effects from the metallic braces, T2-prepared functional MRI showed significantly higher SNR (37.8 ± 2.4 vs 15.5 ± 5.3; P < .001) and contrast-to-noise ratio (0.83 ± 0.16 vs 0.29 ± 0.10; P < .001), whereas diffusion-prepared DTI showed higher SNR (5.8 ± 1.5 vs 3.8 ± 0.7; P = .03) than did conventional EPI methods. Apparent diffusion coefficient and fractional anisotropy were consistent with the literature. Geometric distortion was substantially reduced throughout the brain with the proposed methods (significantly higher Jaccard index, 0.95 ± 0.12 vs 0.81 ± 0.61; P < .001). Conclusion T2-prepared functional MRI and diffusion-prepared diffusion tensor imaging can acquire functional and diffusion MRI, respectively, in healthy human participants wearing metallic dental braces with less susceptibility artifacts and geometric distortion than with conventional echo-planar imaging. © RSNA, 2019 Online supplemental material is available for this article. See also the editorial by Dietrich in this issue.

Neonatal hypoxic encephalopathy: Correlation between post-cooling brain MRI findings and 2 years neurodevelopmental outcome.

Objective:This study aims to evaluate the magnetic resonance imaging (MRI) brain patterns among hypoxic-ischemic encephalopathy (HIE) babies who underwent post-cooling MRI brain as well as to correlate the post-cooling brain scoring with patient's neurodevelopmental outcome at 2 years.Subjects and Methods:It was a retrospective cross sectional study carried out at a tertiary university hospital. Record of patients diagnosed with neonatal HIE from 2007 until 2016 who completed 72 h of cooling therapy and had MRI brain within 2 weeks of life were included in this study. A new scoring system by Trivedi et al. that emphasizes on subcortical deep gray matter and posterior limb internal capsule injury were utilized upon MRI assessment, using TW, T2W, and diffusion-weighted imaging (DWI) sequences. Cumulative MRI brain score was obtained and graded as none, mild, moderate, and severe brain injury. The MRI brain scoring was then correlated with patient's 2 years neurodevelopmental outcome using Fisher's Exact Test.Results:A total of 23 patients were eligible of which 19 term neonates were included. 13% of these neonates (n = 3) had mild MRI brain injury grading with 52.2% (n = 12) moderate and 34.8% (n = 8) severe. There was no significant correlation seen between MRI brain grading and developmental outcome at 2 years old (P > 0.05).Conclusion:There was no significant correlation between neonatal MRI brain injury grading and 2 years neurodevelopmental outcome. Nevertheless, the new MRI brain scoring by Trivedi et al. is reproducible and comprehensive as it involves various important brain structures, assessed from different MRI sequences.

The anterior one third of the posterior limb of the internal capsule is also supplied by the anterior choroidal artery

PurposeIt is universally recognized that the anterior choroidal artery (AChA) supplies the posterior two-third of the posterior limb of internal capsule (PLIC). On the other hand, the blood supply to the anterior one third of the PLIC has remained undetermined. We posit the anterior one third of the PLIC is also supplied by the AChA referring the previous microsurgical descriptions. MethodsNinety consecutive patients with isolated acute infarction in the PLIC were studied. We classified patients into 4 groups. 1. The anterior type that involved the anterior one-third part of the PLIC. 2. The posterior type that involved the caudal two-third part of the PLIC, 3. The combined type that located in the full length of the PLIC, 4. The dot type that restricted within PLIC up to10mm in diameter. ResultsPatient numbers in groups 1 through 4 were 7 (7.7%), 46 (51.1%), 9 (10.6%) and 28 (31.1%). The anterior type involved the medial part of pallidum (MPP) in 5 patients (71.4%) and none in the lateral thalamus (LT), while the posterior type involved MPP only in 6 patients (13.0%) and LT in 33 patients (71.7%). ConclusionCorresponding to previous microsurgical descriptions, an occlusion of the proximal branches may cause anterior type infarct and that of the distal branches may cause posterior type infarcts. The anterior one third of the PLIC is also supplied by the branches of the AChA, albeit the low prevalence.

Feasibility of constructing a unilateral sudden sensorineural hearing loss machine learning classification model based on diffusion tensor imaging

Objective To explore the feasibility of constructing a machine learning classification model for unilateral sudden sensorineural hearing loss (SSHL) patients and normal controls based on diffusion tensor imaging. Methods Prospective collection of 84 patients with untreated SSHL were recruited from the otolaryngology department of the Union Hospital of Tongji Medical College of Huazhong University of Science and Technology between June 2013 to May 2015 as the SSHL group. Meanwhile, a total of 63 healthy volunteers who were no any ear disease history, and the hearing function were confirmed with pure tone audiometry, were collected as the control group. All subjects underwent a brain DTI scan. The data were divided into the training set and validation set according to the ratio of 7 to 3, that was, the training set contained 58 cases of SSHL patients and 44 control groups, and the validation set included 26 cases of SSHL patients and 19 control groups. A vector which included the DTI parameters such as fractional anisotropy, mean diffusivity, axial diffusivity and radial diffusivity was constructed with the software R. The LASSO regression of machine learning method was used to perform feature dimensionality reduction and construct a classification model. The training set samples were used to map the nomogram based on the multivariate logistic analysis method, the validation set and the AUC were used to evaluate the prediction ability of the nomogram, and the calibration curve was used to evaluate the model. Results From the 200 feature vectors including the fractional anisotropy (FA), mean diffusivity (MD), axial diffusivity (AD), and radial diffusivity (RD) values of each brain region, after each dimension reduction process, a total of six features were retained, which were the MD of left superior corona radiate and right superior fronto-occipital fasciculus, the AD of the body of corpus callosum, and the RD of left inferior cerebellar peduncle, left superior corona radiate and right posterior limb of internal capsule. The six features of patients with unilateral SSHL were higher than the control group, and the difference was statistically significant (P<0.05). Based on this, a two-class model is constructed and a nomogram is drawn. The sensitivity, specificity, accuracy and AUC of the training set were 93.1% (54/58), 72.7% (32/44), 84.3% (86/102) and 0.854, respectively; the sensitivity, specificity, accuracy and AUC of validation set were 80.8% (21/26), 84.2% (16/19), 82.2% (37/45), 0.870, respectively. Nomogram could significantly improve the classification efficiency of the control group and patients, and the model with the LASSO method showed a higher prediction curve than other models. Conclusions The machine learning classification model based on DTI metrics can effectively distinguish patients with unilateral sudden sensorineural deafness from healthy control people. Key words: Hearing loss, sensorineural; Diffusion tensor imaging; Machine learning; Classification; Nomogram; Decision curve analysis

Abnormal anisotropic diffusion properties in pediatric myelomeningocele patients treated with fetal surgery: an initial DTI study.

To investigate white matter microstructural abnormality based on diffusion tensor imaging (DTI) in pediatric patients with fetal repair for myelomeningocele (MMC). This was a retrospective analysis of DTI data from 8 pediatric patients with prenatal MMC repair (age range 1.64-33.70months; sex 3F/5M) and 8 age-matched controls (age 2.24-31.20months; sex 5F/2M). All participants were scanned on 1.5T GE Signa MR scanner (GE Healthcare, Milwaukee, WI) with the same sequence specifications. Two DTI measures, including fractional anisotropy (FA) and mean diffusivity (MD), were calculated from the genu of corpus callosum (gCC) and the posterior limb of internal capsule (PLIC). DTI values and fronto-occipital horn ratio (FOHR) were tested for group difference based on two-tailed paired t test. The ventricle size based on FOHR in patients with prenatal MMC repair was significantly larger than that in the age-matched control group (p < 0.001). Statistically significant group difference in DTI (lower FA and higher MD in patient group) was found in gCC (p = 0.007 and 0.003, respectively). A trend level increase in MD was also found (p = 0.065) in PLIC in patients when compared with the age-matched controls. Our data showed white matter abnormality based on DTI in pediatric patient with fetal repair for MMC. The sensitivity of DTI in detecting white matter abnormality, as shown in the present study, may help to serve as an imaging biomarker for assessing hydrocephalus and improve and optimize decision making for the treatment of hydrocephalus in this patient population.

Acute Subcortical Infarcts Cause Secondary Degeneration in the Remote Non-involved Cortex and Connecting Fiber Tracts.

Background and Purpose: Remote white matter and cortex reorganization may contribute to functional reorganization and clinical outcome after acute infarcts. To determine the microstructural changes in the remote intact corticospinal tract (CST) and precentral gyrus cortex connected to the acute infarct after subcortical stroke involving the CST over 6 months.Methods: Twenty-two patients with subcortical stroke involving the CST underwent magnetic resonance imaging (MRI) and clinical assessment in the acute phase (baseline) and 6 months (follow–up) after the stroke. The MRI sequences included T1-weighted imaging, T2–weighted imaging, fluid-attenuated inversion recovery, diffusion tensor imaging (DTI), and diffusion kurtosis imaging. Fractional anisotropy (FA) and track–density imaging (TDI) values were generated using DTI data for the centrum semiovale, corona radiata, posterior limb of internal capsule, and cerebral peduncle. The mean kurtosis (MK) value of the precentral gyrus cortex was calculated. Changes in the FA, TDI, and MK values between the baseline and follow-up and the relationship between these changes were analyzed.Results: The TDI and FA values of all parts of the ipsilesional (IL) CST, including the noninvolved upper and lower parts, decreased at the 6-month follow-up (P < 0.001). The MK values of the stroke lesion (P < 0.001) and IL precentral gyrus cortex (P = 0.002) were lower at follow-up than at the baseline. The ΔTDI (r = 0.689, P < 0.001) and Δ FA values (r = 0.463, P = 0.03) of the noninvolved upper part of the IL CST were positively correlated with the ΔMK value of the IL precentral gyrus cortex.Conclusion: Secondary degeneration occurred in the remote part of the CST and the remote IL precentral gyrus cortex after subcortical stroke involving the CST. The secondary degeneration in the upper part of the CST was correlated with that in the IL precentral gyrus cortex.

Influence of Intracerebral Hemorrhage Location on Outcomes in Patients With Severe Intraventricular Hemorrhage.

Background and Purpose- We investigated the prognostic significance of spontaneous intracerebral hemorrhage location in presence of severe intraventricular hemorrhage. Methods- We analyzed diagnostic computed tomography scans from 467/500 (excluding primary intraventricular hemorrhage) subjects from the CLEAR (Clot Lysis: Evaluating Accelerated Resolution of Intraventricular Hemorrhage) III trial. We measured intracerebral hemorrhage engagement with specific anatomic regions, and estimated association of each region with blinded assessment of dichotomized poor stroke outcomes: mortality, modified Rankin Scale score of 4 to 6, National Institutes of Health Stroke Scale score of >4, stroke impact scale score of <60, Barthel Index <86, and EuroQol visual analogue scale score of <50 and <70 at days 30 and 180, respectively, using logistic regression models. Results- Frequency of anatomic region involvement consisted of thalamus (332 lesions, 71.1% of subjects), caudate (219, 46.9%), posterior limb internal capsule (188, 40.3%), globus pallidus/putamen (127, 27.2%), anterior limb internal capsule (108, 23.1%), and lobar (29, 6.2%). Thalamic location was independently associated with mortality (days 30 and 180) and with poor outcomes on most stroke scales at day 180 on adjusted analysis. Posterior limb internal capsule and globus pallidus/putamen involvement was associated with increased odds of worse disability at days 30 and 180. Anterior limb internal capsule and caudate locations were associated with decreased mortality on days 30 and 180. Anterior limb internal capsule lesions were associated with decreased long-term morbidity. Conclusions- Acute intracerebral hemorrhage lesion topography provides important insights into anatomic correlates of mortality and functional outcomes even in severe intraventricular hemorrhage causing obstructive hydrocephalus. Models accounting for intracerebral hemorrhage location in addition to volumes may improve outcome prediction and permit stratification of benefit from aggressive acute interventions. Clinical Trial Registration- URL: https://www.clinicaltrials.gov . Unique identifier: NCT00784134.

Associated factors of early neurological deterioration in isolated acute lacunar infarction in basal ganglia

Objective:To investigate, in basal ganglia, the factors associated with early neurological deterioration (END) of isolated acute lacunar infarction.Methods:167 patients, in the retrospective group, with isolated acute lacunar infarction in basal ganglia, were defined by magnetic resonance imaging (MRI). The National Institutes of Health Stroke Scale (NIHSS) defined early neurological deterioration as increases of ≥ 2 within 72 hours following admission. Baseline variables predicting END were investigated with multivariate logistic regression analysis.Results:In the study, END occurred in 42 (25.15%) patients. Lesions located in posterior limb of internal capsule were independent risk factors for END (P &lt; 0.01). Associated with END were the age of onset, history of cerebral infarction, history of diabetes, systolic blood pressure at admission and lesions of cerebral white matter. This presented significant differences (P &lt; 0.05). With or without diabetes and different lesion location at varying layers and inter-layers, single-factor and multi-factor analysis revealed no effect on the association between positive ENT and age, history of stroke, white matter. Previous history of stroke, pathological changes of white matter, and age of onset, correlates with END which showed significant difference (P &lt; 0.05).Conclusions:There is a close relationship between the lesion location and other related factors, such as lesions of cerebral white matter, history of cerebral infarction, history of diabetes and age, etc. and END in patients with isolated acute lacunar infarction in basal ganglia. Protective factors of END included age ≥ 65, high systolic pressure, stroke history, cerebral white matter lesions in our study.

Altered white matter microstructure in patients with post-stroke depression detected by diffusion kurtosis imaging.

The aim of our study is to determine the pathological changes of white matter microstructure in patients with early post-stroke depression (PSD), and to investigate the association between white matter integrity examined by diffusion kurtosis imaging (DKI) and early PSD. Thirty-eight patients with acute cerebral infarction were selected, including 17 patients with depression (PSD group), and 21 patients without depression (N-PSD group). In addition, 20 normal healthy controls (NORM group) were selected. All were taken DKI scans. The white matter of the frontal lobe, temporal lobe, parietal lobe, occipital lobe, anterior limb of internal capsule, and posterior limb of internal capsule, in addition to the genu of corpus callosum and splenium of corpus callosum was selected as a region of interest (ROI). Selected parameters include fractional anisotropy (FA) and mean kurtosis (MK). Compared with N-PSD group and NORM group, FA value of the left frontal lobe and MK value of the bilateral frontal lobe, bilateral temporal lobe, and genu of corpus callosum in PSD group were decreased (P < 0.05). Our results indicated that the early PSD patients had white matter microstructure abnormalities in the frontal lobe, temporal lobe, and genu of corpus callosum. DKI provides a comprehensive brain imaging reference for detecting early microstructural damage of white matter in PSD patients, which can be used as an imaging biomarker to detect early PSD and its progression potentially.

Evaluation of Diffusional Kurtosis Imaging in Sub-acute Ischemic Stroke: Comparison with Rehabilitation Treatment Effect

Stroke is a serious worldwide medical condition that causes neurological function disability. Diffusional kurtosis imaging, which measures the non-Gaussianity of water diffusion, has been demonstrated to be a sensitive biomarker in many neuro-pathologies. This study explores the relationship between neural function recovery and transformation of the ischemic lesion and/or corticospinal tract during the sub-acute phase after stroke by using diffusional kurtosis imaging. We performed a prospective study of function recovery and K metrics of 43 patients with sub-acute ischemic stroke in the middle cerebral artery territory. The effect of rehabilitation treatment was evaluated using both the Fugl-Meyer motor function score and modified Barthel index score at post-treatment compared with admission, and patients were allocated to two groups: good and poor rehabilitation effect (GRE and PRE). Metrics of diffusional kurtosis imaging within ischemic lesion and along the corticospinal tract were acquired, respectively. All three relative axial diffusional kurtoses (rKas) along the corticospinal tract in the GRE group (n = 21) were significantly larger than those of the PRE group (n = 22), including rKa in the posterior limb of internal capsule, rKa in the cerebral peduncle, and rKa in the basal part of the pons (p = 0.014, 0.005, and 0.021, respectively). This multi-parametric magnetic resonance imaging study showed that diffusional kurtosis imaging has the potential to complement existing stroke imaging techniques and revealed its own advantages in elucidating the possible biophysical mechanism of functional restoration underlying ischemic stroke.

Research on mode of anisotropy and other diffusion tensor imaging derived indices of white matter with mild to moderate Alzheimer disease based on tract based spatial statistics

Objective We performed a diffusion tensor imaging (DTI) study to explore the value of mode of anisotropy (MO) and other DTI-derived indices in assessing white matter fiber damage with mild to moderate Alzheimer disease (AD) patients. Methods This study was a prospective study. From February 2015 to February 2018, 33 patients with mild to moderate AD according to criteria were prospectively recruited as AD group at the First Affiliated Hospital of Wenzhou Medical University. Twenty healthy age-, sex-matched volunteers were recruited as normoal conctrast (NC) group. All subjects were performed by conventional brain MRI and DTI scans. The MO, anisotropic fraction (FA), mean diffusivity (MD), radial diffusivity (RD) and axial diffusivity (AxD) of white matter fibers were obtained from DTI images after TBSS post-processing. The statistical analyses of DTI indices between AD group and NC group were carried out in Functional MRI Software Library software. Results As compared with NC group, we found 1 cluster with significant decrease FA and increase RD in AD group, the affected fibers involving bilateral anterior thalamic radiation, corticospinal tract, cingulate gyrus, hippocampus, inferior fronto-occipital fasciculus, inferior longitudinal fasciculus, uncinated fasciculus, superior longitudinal fasciculus (P<0.05). The MD value increase(P<0.1) was found to coincide with the decrease of FA and the increase of RD, while no significant increase or decrease in P<0.05. Three clusters of MO increases (P<0.05) accompanying with increases of AxD were found in left anterior limb of internal capsule, bilateral posterior limb of internal capsule, posterior forceps, left centrum semiovale and parietal lobe. Two clusters of MO decreases (P<0.05) accompanying with decreases of FA and increases of RD were found in fornix, forceps, external capsule, centrum semiovale and left frontal lobe. Conclusions The combination of MO with DTI routine tensor indices (FA, RD, MD, AxD) can further reveal the microstructural damage of white matter fibers in AD, especially to crossing-fibers. The abnormalities of MO combined with FA, RD and MD reveal the degeneration of both bundles of crossing-fibers, and the abnormalities of MO combined with AxD reveal that the white matter damage was mainly caused by axon damage of one bundle of cross fibers. Key words: Alzheimer disease; Diffusion tensor imaging; Mode of anisotropy; Comparative study

A single season of soccer results in no significant neurophysiological changes in adolescent female athletes

Introduction Sports related mild traumatic brain injury (mTBI) is a serious and increasing health incident in the United States, particularly in young children and adolescents, often affecting developing frontal and temporal lobes. Literature comparing various methods of cognitive assessment tools as well as the utility of various non-invasive brain imaging technologies in the diagnosis and follow up of mTBI lacks standardized methods and requires further investigation. We investigated the stability of intercortical and intracortical inhibition parameters and their relationship to white matter integrity, in athletes without mTBI. We hypothesized that a single season of soccer, without a concussion, would result in no significant neurophysiologic differences, in female adolescents. Methods Ten female soccer athletes, between the ages of 14–17 years were evaluated pre and post season using: neuropsychological testing, transcranial magnetic stimulation (TMS), anatomical MRI, and diffusion tensor imaging (DTI). One athlete sustained a concussion and was subsequently removed from analysis. Results There was no significant difference when comparing pre- and post-season measures for: neuropsychological testing; intercortical ( p = 0.812) or intracortical ( p = 0.888) inhibition, measured by duration of silent periods during TMS; motor evoked potential onset ( p = 0.227) or duration ( p = 0.977); and interhemispheric conduction times ( p = 0.092). In addition, no significant difference was found between pre and post assessments of fractional anisotropy, for white matter tracts of interest: posterior limb of internal capsule; cortical spinal tracts; and genu, body, and splenium of the corpus callosum. Conclusion Following a season of soccer, there was no difference in any neurologic parameters that would elicit concern for the continuation of the sport at this level. We demonstrate that the inter- and intra-cortical inhibitory parameters derived from TMS are stable; therefore, TMS and DTI can be used as reliable measures for further investigation of patients sustaining mTBI.

Constrained-induced movement therapy promotes motor function recovery by enhancing the remodeling of ipsilesional corticospinal tract in rats after stroke

Constraint-induced movement therapy (CIMT), which forces the use of the impaired limb by restraining the unaffected limb, has been used extensively for the recovery of limb motor function after stroke. However, the underlying mechanism of CIMT remains unclear. Diffusion tensor imaging (DTI) is a well-known neuroimaging technique that reflects the microstructure of white matter tracts and potential changes associated with different treatments. The aim of this study is to use DTI imaging to determine how corticospinal tract (CST) fibers remodel in ischemic rats with CIMT. In the present study, rats were randomly divided into three groups: a middle cerebral artery occlusion group (MCAO), a therapeutic group (MCAO + CIMT), and a sham-operated group (sham). A plaster cast was used to restrict the unaffected limb of the rats in the MCAO + CIMT group for 14 days. The Catwalk system was used to assess the limb motor function of rats. Fractional anisotropy (FA) and the average diffusion coefficient (ADC) of the CST were quantified through DTI. The expression of the c-Jun–N-terminal kinase signaling pathway (JNK) was examined after 14 days of CIMT. We found that CIMT could accelerate and enhance motor function recovery, and the MCAO + CIMT group showed significantly increased FA values in the ipsilesional posterior limb of internal capsule (PLIC) compared with the MCAO group. In addition, we found no significant difference in the ratio of phosphorylated-JNK/total-JNK among the three groups, whereas the expression of P-JNK decreased significantly in the chronic phase of stroke. In conclusion, CIMT-induced functional recovery following ischemic stroke through facilitation of the remodeling of ipsilesional CST, and restoration after ischemic stroke may be associated with the declining value of the ratio of P-JNK/JNK.

Magnetic resonance spectroscopy assessment of brain injury after moderate hypothermia in neonatal encephalopathy: a prospective multicentre cohort study

SummaryBackgroundIn neonatal encephalopathy, the clinical manifestations of injury can only be reliably assessed several years after an intervention, complicating early prognostication and rendering trials of promising neuroprotectants slow and expensive. We aimed to determine the accuracy of thalamic proton magnetic resonance (MR) spectroscopy (MRS) biomarkers as early predictors of the neurodevelopmental abnormalities observed years after neonatal encephalopathy.MethodsWe did a prospective multicentre cohort study across eight neonatal intensive care units in the UK and USA, recruiting term and near-term neonates who received therapeutic hypothermia for neonatal encephalopathy. We excluded infants with life-threatening congenital malformations, syndromic disorders, neurometabolic diseases, or any alternative diagnoses for encephalopathy that were apparent within 6 h of birth. We obtained T1-weighted, T2-weighted, and diffusion-weighted MRI and thalamic proton MRS 4–14 days after birth. Clinical neurodevelopmental tests were done 18–24 months later. The primary outcome was the association between MR biomarkers and an adverse neurodevelopmental outcome, defined as death or moderate or severe disability, measured using a multivariable prognostic model. We used receiver operating characteristic (ROC) curves to examine the prognostic accuracy of the individual biomarkers. This trial is registered with ClinicalTrials.gov, number NCT01309711.FindingsBetween Jan 29, 2013, and June 25, 2016, we recruited 223 infants who all underwent MRI and MRS at a median age of 7 days (IQR 5–10), with 190 (85%) followed up for neurological examination at a median age of 23 months (20–25). Of those followed up, 31 (16%) had moderate or severe disability, including one death. Multiple logistic regression analysis could not be done because thalamic N-acetylaspartate (NAA) concentration alone accurately predicted an adverse neurodevelopmental outcome (area under the curve [AUC] of 0·99 [95% CI 0·94–1·00]; sensitivity 100% [74–100]; specificity 97% [90–100]; n=82); the models would not converge when any additional variable was examined. The AUC (95% CI) of clinical examination at 6 h (n=190) and at discharge (n=167) were 0·72 (0·65–0·78) and 0·60 (0·53–0·68), respectively, and the AUC of abnormal amplitude integrated EEG at 6 h (n=169) was 0·73 (0·65–0·79). On conventional MRI (n=190), cortical injury had an AUC of 0·67 (0·60–0·73), basal ganglia or thalamic injury had an AUC of 0·81 (0·75–0·87), and abnormal signal in the posterior limb of internal capsule (PLIC) had an AUC of 0·82 (0·76–0·87). Fractional anisotropy of PLIC (n=65) had an AUC of 0·82 (0·76–0·87). MRS metabolite peak-area ratios (n=160) of NAA–creatine (<1·29) had an AUC of 0·79 (0·72–0·85), of NAA–choline had an AUC of 0·74 (0·66–0·80), and of lactate–NAA (>0·22) had an AUC of 0·94 (0·89–0·97).InterpretationThalamic proton MRS measures acquired soon after birth in neonatal encephalopathy had the highest accuracy to predict neurdevelopment 2 years later. These methods could be applied to increase the power of neuroprotection trials while reducing their duration.FundingNational Institute for Health Research UK.

Bilateral Lesions in the Posterior Limb of Internal Capsule Attributed to Combination Therapy of Isoniazid and Rifampin

Bilateral Lesions in the Posterior Limb of Internal Capsule Attributed to Combination Therapy of Isoniazid and Rifampin

Individualized prediction of dispositional worry using white matter connectivity.

Excessive worry is a defining feature of generalized anxiety disorder and is present in a wide range of other psychiatric conditions. Therefore, individualized predictions of worry propensity could be highly relevant in clinical practice, with respect to the assessment of worry symptom severity at the individual level. We applied a multivariate machine learning approach to predict dispositional worry based on microstructural integrity of white matter (WM) tracts. We demonstrated that the machine learning model was able to decode individual dispositional worry scores from microstructural properties in widely distributed WM tracts (mean absolute error = 10.46, p < 0.001; root mean squared error = 12.82, p < 0.001; prediction R2 = 0.17, p < 0.001). WM tracts that contributed to worry prediction included the posterior limb of internal capsule, anterior corona radiate, and cerebral peduncle, as well as the corticolimbic pathways (e.g. uncinate fasciculus, cingulum, and fornix) already known to be critical for emotion processing and regulation. The current work thus elucidates potential neuromarkers for clinical assessment of worry symptoms across a wide range of psychiatric disorders. In addition, the identification of widely distributed pathways underlying worry propensity serves to better improve the understanding of the neurobiological mechanisms associated with worry.

Neonatal meningitis: Preterm and term infants evaluated by magnetic-resonance-imaging-based score analysis

ObjectivesTo investigate the difference of brain damages between preterm and term infants with bacterial meningitis by using MRI-based score analysis. MethodsThe clinical information and MRI dataset of 65 newborns with meningitis were reviewed, including 18 preterm infants and 47 term ones. There were 13 basic brain injury patterns identified on cranial MRI. And the severity of these injuries was graded from score 1 to 3. These 13 patterns were further classified into three major groups – white matter abnormalities (WMA), gray matter abnormalities (GMA) and non-parenchyma abnormalities (NPA). ResultsOf all the newborns, 63% presented with cerebral lesions (41/65) and 3% presented with cerebral plus cerebellar damages (2/65). The incidence and MRI-based score of abnormal myelination of the posterior limb of internal capsules, ventricular dilatation and periventricular white matter volume loss were significantly higher in the preterm than the term group. Regarding WMA, GMA and NPA, the score of WMA in the preterm group was significantly higher than that of the term group (p = .000). While, the differences of GMA and NPA scores between the preterm and the term groups were not significant (p = .076, .224, respectively). ConclusionWhite matter abnormalities were more frequently seen in the preterm infants with meningitis.