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Objective: Thalamic gliomas in children are less suitable for surgical resection because of their location. In cases of unavoidable resection, careful surgical planning in addition to histology and extent of resection affects prognosis., Methods: A cohort of 10 pediatric patients with thalamic glioma underwent surgical resection at our department. The predominant location of tumor origins in the thalamus was defined in imaging studies. Histopathology was determined (retrospectively in a subset) according to the World Health Organization classification 2016, including the newly established type of "diffuse midline glioma, H3 K27M-mutant.", Results: Three low-grade gliomas (grade I/II) and 7 high-grade gliomas (grade III/IV) were identified. The mean follow-up period was 49.8 months. All 3 low-grade gliomas did not recur (progression-free survival, 58.3 months). Six of 7 high-grade gliomas recurred, and the patients died of the primary disease (overall survival, 28.1 months). Poor outcomes, especially when located at the pulvinar region, were noticeable, with strong predictive power for poor prognosis (P = 0.0018). The presence of H3 K27M mutation and pulvinar location were closely associated (P = 0.0036). Four of 5 patients with pulvinar region tumors developed dissemination and died of the primary disease., Conclusions: Pulvinar location is specifically associated with a high rate of malignancy in histology, the presence of H3 K27M mutation, and dissemination at an early disease stage. This association suggests that a distinct biological profile affects prognosis depending on location within the thalamus, especially the pulvinar. We report that tumor location is highly relevant to prognosis and should be taken into consideration when planning treatment., (Copyright © 2019 Elsevier Inc. All rights reserved.)

Background: Posterior cortical atrophy (PCA) is a clinical variant of Alzheimer's disease (AD) that presents with progressive visuospatial symptoms. While amnestic AD is characterized by disrupted default mode network (DMN) connectivity with corresponding increases in salience network (SN) connectivity, a visuospatial network appears to be disrupted early in PCA. Based on PCA patients' clinical features, we hypothesized that, in addition to early decreased integrity within the visuospatial network, patients with PCA would show increases in SN connectivity despite relative preservation of DMN. As the lateral pulvinar nucleus of the thalamus has direct anatomical connections with striate and extrastriate cortex and DMN, and the medial pulvinar is anatomically interconnected with SN, we further hypothesized that lateral and medial pulvinar nuclei might be implicated in intrinsic connectivity changes in PCA., Methods: 26 patients with PCA and 64 matched controls were recruited through UCSF Memory and Aging Center research programs. Each completed a standardized neuropsychological battery, structural MRI, and task-free fMRI. Seed-based functional correlations were used to probe networks of interest, including those seeded by the medial and lateral pulvinar thalamic nuclei, across the whole brain, and functional data analyses were adjusted for brain atrophy., Results: Patients with PCA showed disproportionate deficits in the visuospatial domain; they also showed preserved social sensitivity and endorsed more depressive symptoms than HCs. PCA patients had significant parietooccipital atrophy accompanied by widespread connectivity decreases within the visuospatial network, enhanced connectivity between some structures in SN, and enhanced connectivity between key nodes of the DMN compared to controls. Increased SN connectivity correlated with a measure of social sensitivity, and increased DMN connectivity correlated with short-term memory performance. Medial pulvinar connectivity increases in PCA were topographically similar to SN (anterior insula) connectivity increases, while lateral pulvinar connectivity increases were similar to DMN (posterior cingulate) connectivity increases., Conclusions: PCA is characterized by preserved to heightened connectivity in the SN and DMN despite decreased visuospatial network connectivity. The spatial similarity of medial and lateral pulvinar connectivity changes to those seen in the SN and DMN suggests a role for the pulvinar in intrinsic connectivity network changes in PCA., (Copyright © 2018 The Authors. Published by Elsevier Inc. All rights reserved.)

Anorexia nervosa (AN) is a psychiatric disorder, in which the prognosis for some patients is poor. The etiology and effective treatments for AN have not been established. We examined morphometric changes in the brain of AN and clarified how the changes were associated with symptoms and pathophysiology. We enrolled 52 participants: 7 with the restrictive type of AN, 13 with the binge-eating/purging type, 3 with eating disorder not otherwise specified, and 29 healthy controls. Participants underwent T1-weighted MRI. Group differences between patients and controls in gray matter volume (GMV) were analyzed using voxel-based morphometry. Age and body mass index (BMI) were considered covariates. Correlations between regional GMVs and drive for thinness and body dissatisfaction were examined. Patients had decreased GMV in the superior/middle temporal gyrus (STG/MTG), pulvinar, and superior frontal gyrus after correction for age and BMI, and in the STG/MTG, middle frontal gyrus, and cingulate after correction for age. A correlational group difference was detected for body dissatisfaction and GMV in the STG. Our findings suggest that decreased GMV in the STG is related to body dissatisfaction that could come from impaired visuospatial perception, together with GMV decreases in several regions, which may be involved in development of AN., (Copyright © 2017 Elsevier Ireland Ltd. All rights reserved.)

Increased brain iron levels may be a risk factor for age-related neurologic disorders. Little is known about factors other than age and sex potentially affecting brain iron concentration. We investigated dietary habits (iron and calcium supplements, dairy products, vegetables, and red meat) as a potential modifiable predictor of brain iron levels using 3-T susceptibility-weighted magnetic resonance imaging. One hundred ninety volunteers were scanned, and mean phase and mean phase of low-phase voxels were determined for deep gray-matter (DGM) structures, including the caudate, putamen, thalamus, pulvinar, hippocampus, amygdala, red nucleus, and substantia nigra. There was a trend for lower mean phase (suggestive of high iron levels) in individuals taking iron supplements (p = 0.075). Among men, both increased dairy and vegetable intakes were significantly associated with lower DGM mean phase (p < 0.05) and mean phase of low-phase voxels (p < 0.05) in the thalamus, pulvinar, and red nucleus. In contrast, among women, iron levels were not associated with dairy consumption (p > 0.05) in the DGM but were inversely associated with vegetable intake in the thalamus (p = 0.006). Brain iron levels appear to be modulated by diet, with effects being highly dependent on gender., (Published by Elsevier Inc.)

Recent work has identified disruption of several brain networks involving limbic and cortical regions that contribute to the generation of diverse symptoms of major depressive disorder (MDD). Of particular interest are the networks anchored on the right anterior insula, which binds the cortical and limbic regions to enable key functions that integrate bottom-up and top-down information in emotional and cognitive processing. Emotional appraisal has been linked to a presumed hierarchy of processing, from sensory percepts to affective states. But it is unclear whether the network level dysfunction seen in depression relates to a breakdown of this presumed hierarchical processing system from sensory to higher cognitive regions, mediated by core limbic regions (e.g. insula). In 16 patients with current MDD, and 16 healthy controls, we investigated differences in directional influences between anterior insula and the rest of the brain using resting-state functional magnetic resonance imaging (fMRI) and Granger-causal analysis (GCA), using anterior insula as a seed region. Results showed a failure of reciprocal influence between insula and higher frontal regions (dorsomedial prefrontal cortex) in addition to a weakening of influences from sensory regions (pulvinar and visual cortex) to the insula. This suggests dysfunction of both sensory and putative self-processing regulatory loops centered around the insula in MDD. For the first time, we demonstrate a network-level processing defect extending from sensory to frontal regions through insula in depression. Within limitations of inferences drawn from GCA of resting fMRI, we offer a novel framework to advance targeted network modulation approaches to treat depression., (Copyright © 2014 Elsevier B.V. and ECNP. All rights reserved.)

Purpose: To define the neuropathological findings of pulvinar degeneration seen in long duration status epilepticus., Methods: We review the clinical, radiologic, neurophysiologic, investigational and neuropathological findings on a 27 year old woman who died after 162 days of prolonged refractory status epilepticus., Results: Continuous EEG monitoring confirmed recurrent uncontrolled seizure activity bilaterally and independently, most frequent in the right fronto-temporal region. Initial MRI of the brain was normal. Repeat study until on day 127 of admission showed advanced changes, with bilateral pulvinar T2/FLAIR hyperintensities. The autopsy revealed sharply defined, grey, soft, granular nodules in each medial pulvinar nucleus. Microscopically these consisted of sharply defined paucicellular areas with loss of neurons and myelin and with numerous macrophages in their centers, surrounded by reactive astrocytes with relatively spared of axons. The spinal cord at cervical and thoracic levels showed symmetric spongy vacuolation in the central part of the dorsal columns and lateral corticospinal tracts, with mild myelin loss, relatively preserved axons. The pathological lesions found in this case in thepulvinar are somewhat similar to the pathologic lesions described in Wernicke's encephalopathy. Those found in the spinal cord of our patient resemble characteristic features of B12 related subacute combined degeneration., Conclusion: Characteristic pulvinar degeneration may be found as an acquired phenomenon in prolonged refractory status epilepticus. We hypothesize that the neuropathological findings result from an excessive focal metabolic demand, secondary to neuronal network over activation in the setting of prolonged, frequent bi-temporal seizures., (Copyright © 2013 British Epilepsy Association. Published by Elsevier Ltd. All rights reserved.)

Purpose: To report on iodine-125 (I125) interstitial irradiation in the treatment of low grade brain stem gliomas in adults., Patients and Methods: Ten patients with well-circumscribed lesions of the brainstem and histological confirmation of low grade glioma treated with stereotactically implanted I-125 seed in our department between 1995 and 2012 were retrospectively analyzed., Results: In 9 patients the lesion was treated with one I-125 seed and in one patient, 2 spatial separated lesions were implanted, therefore a total of 11 I-125 seeds were implanted. The mean volume of the 11 lesions was 2.76 ml (range: 0.5-7.2 ml), mean activity of the seeds was 6.23 mCi (range: 1.5-11.1 mCi), mean duration of irradiation was 28.5 days (range: 21-41 days) and mean effective dose rate was 9.16 cGy/h (range: 6.2-12 cGy/h). The 30 days perioperative morbidity and mortality rate was 0%. Median follow up was 72.5 month (range 5-168 months). Six of ten patients were free of progression until last follow up., Conclusion: In our experience at the University Clinic in Freiburg Germany, interstitial radiosurgery based on MRI is a safe and effective method to diagnose and treat low grade gliomas of the brain stem. Furthermore randomized studies are needed to confirm the therapeutic impact of this method in comparison to external beam radiation of brain stem gliomas., (Copyright © 2013 Elsevier B.V. All rights reserved.)

Objective: The neurobiological basis of inattentiveness, a core feature of attention-deficit/hyperactivity disorder (ADHD), is not yet well understood. Structural abnormalities in thalamus, especially the pulvinar nuclei, have recently been reported in ADHD. Pulvinar nuclei maintain reciprocal connections with cortical/subcortical areas, and play a central coordinating role during visual attention processing. The objective of this study was to test the hypothesis that children and young adolescents with ADHD would show atypical pulvinar-cortical functional pathways during sustained attention performance, and that these functional abnormalities would be associated with the inattentive symptoms of the disorder., Method: Visual attention task-based functional magnetic resonance imaging (fMRI) data from 22 children and young adolescents with ADHD and 22 demographically matched, normal control subjects were analyzed. Cortical activation maps and temporal correlations of activity patterns between pulvinar nuclei and the remainder of brain were constructed for each participant. Correlations between activation magnitude of pulvinar and diagnostic measures were calculated in subjects with ADHD., Results: Compared to controls, subjects with ADHD showed significantly reduced pulvinar activations bilaterally, significantly decreased functional connectivity between bilateral pulvinar and right prefrontal regions, and significantly increased connectivity between the right pulvinar and bilateral occipital regions. In addition, the activation magnitude in the left pulvinar was negatively correlated with the DSM-IV inattentive index in ADHD group., Conclusions: Allied with previous evidence of structural abnormalities in pulvinar, the current data suggest that inappropriate development of pulvinar may lead to disrupted functional circuits for visual attention processing, and that these disruptions contribute significantly to the pathophysiological mechanisms of the inattentiveness symptoms in ADHD., (Copyright © 2012 American Academy of Child and Adolescent Psychiatry. Published by Elsevier Inc. All rights reserved.)

The pulvinar nucleus of the thalamus has been considered as a key structure for visual attention functions (Grieve, K.L. et al. (2000). Trends Neurosci., 23: 35-39; Shipp, S. (2003). Philos. Trans. R. Soc. Lond. B Biol. Sci., 358(1438): 1605-1624). During the past several years, we have studied the role of the human pulvinar in visual attention and oculomotor behaviour by testing a small group of patients with unilateral pulvinar lesions. Here we summarize some of these findings, and present new evidence for the role of this structure in both eye movements and visual attention through two versions of a temporal-order judgment task and an antisaccade task. Pulvinar damage induces an ipsilesional bias in perceptual temporal-order judgments and in saccadic decision, and also increases the latency of antisaccades away from contralesional targets. The demonstration that pulvinar damage affects both attention and oculomotor behaviour highlights the role of this structure in the integration of visual and oculomotor signals and, more generally, its role in flexibly linking visual stimuli with context-specific motor responses.