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Clinical Neurology and Neurosurgery Dec 2023Emerging neuromodulatory treatments, such as deep brain stimulation (DBS) and responsive neurostimulation (RNS), have shown promise in reducing drug-resistant seizures....
Emerging neuromodulatory treatments, such as deep brain stimulation (DBS) and responsive neurostimulation (RNS), have shown promise in reducing drug-resistant seizures. While centromedian thalamic nucleus and anterior thalamic nucleus stimulation have been effective in certain types of seizures, limited research has explored pulvinar nucleus stimulation for epilepsy. To address this gap, we conducted a systematic review and individual patient data analysis. Of 78 resultant articles, 5 studies with transient stimulation and chronic stimulation of the pulvinar nucleus were included. Of the 20 patients reviewed, 65% of patients had temporal lobe seizures, while 20% had temporooccipital/occipital lobe seizures. Transient stimulation studies via stereoelectroencephalography (SEEG) showed pulvinar evoked potential response rates of 80% in the mesial temporal region, 76% in the temporal neocortex, and 67% in the TP junction. Another study reported clinically less severe seizures in 62.5% of patients with pulvinar stimulation. In chronic stimulation studies, 80% of patients responded to RNS or DBS, and 2 of 4 patients experienced > 90% seizure reduction. The pulvinar nucleus of the thalamus emerges as a potential target for chronic stimulation in drug-resistant epilepsy. However, knowledge regarding pulvinar connectivity and chronic stimulation remains limited. Further research should investigate specific subregions of the pulvinar for epilepsy treatment. Understanding the role of pulvinar stimulation and its cortical connectivity will advance therapeutic interventions for epilepsy patients.
Topics: Humans; Pulvinar; Hippocampus; Deep Brain Stimulation; Epilepsy; Thalamus; Seizures; Drug Resistant Epilepsy; Anterior Thalamic Nuclei; Data Analysis
PubMed: 37979562
DOI: 10.1016/j.clineuro.2023.108041 -
Advances in Anatomy, Embryology, and... 2018Cytochemical and immunocytochemical methods reveal details of the pulvinar architecture that are not apparent from Nissl and myelin staining. The results of these...
Cytochemical and immunocytochemical methods reveal details of the pulvinar architecture that are not apparent from Nissl and myelin staining. The results of these techniques have been interpreted in different ways by different investigators, each adopting different sets of nomenclature for the various pulvinar subdivisions. In this chapter, we discuss the notion that the differentiation of the pulvinar along primate evolution took place upon a relatively rigid chemoarchitectonic scaffold.
Topics: Animals; Biological Evolution; Immunohistochemistry; Primates; Pulvinar; Visual Pathways
PubMed: 29116444
DOI: 10.1007/978-3-319-70046-5_3 -
NeuroImage Feb 2023Selective attention mechanisms operate across large-scale cortical networks by amplifying behaviorally relevant sensory information while suppressing interference from...
Selective attention mechanisms operate across large-scale cortical networks by amplifying behaviorally relevant sensory information while suppressing interference from distractors. Although it is known that fronto-parietal regions convey information about attentional priorities, it is unclear how such cortical communication is orchestrated. Based on its unique connectivity pattern with the cortex, we hypothesized that the pulvinar, a nucleus of the thalamus, may play a key role in coordinating and modulating remote cortical activity during selective attention. By using a visual task that orthogonally manipulated top-down selection and bottom-up competition during functional MRI, we investigated the modulations induced by task-relevant (spatial cue) and task-irrelevant but salient (distractor) stimuli on functional interactions between the pulvinar, occipito-temporal cortex, and frontoparietal areas involved in selective attention. Pulvinar activity and connectivity were distinctively modulated during the co-occurrence of the cue and salient distractor stimuli, as opposed to the presence of one of these factors alone. Causal modelling analysis further indicated that the pulvinar acted by weighting excitatory signals to cortical areas, predominantly in the presence of both the cue and the distractor. These results converge to support a pivotal role of the pulvinar in integrating top-down and bottom-up signals among distributed networks when confronted with conflicting visual stimuli, and thus contributing to shape priority maps for the guidance of attention.
Topics: Humans; Pulvinar; Thalamus; Parietal Lobe; Frontal Lobe; Magnetic Resonance Imaging
PubMed: 36572132
DOI: 10.1016/j.neuroimage.2022.119832 -
European Journal of Radiology Jun 2021Screening modalities for Developmental Dysplasia of the Hip (DDH) and indications for treatment of mild forms remain controversial. Ultrasound (US) measurement of the... (Observational Study)
Observational Study
PURPOSE
Screening modalities for Developmental Dysplasia of the Hip (DDH) and indications for treatment of mild forms remain controversial. Ultrasound (US) measurement of the pubofemoral distance (PFD > 6 mm, composed of the pubic cartilage and the pulvinar) can avoid late diagnoses of DDH. A thick pubic cartilage may nevertheless lead to false positives. The purpose of this study was to establish standard measurements of pubic cartilage and pulvinar, through universal US screening, to lower false positive results and thus any overtreatment.
METHODS
This is a single-center observational prospective study conducted from December 2016 to January 2018, on infants who underwent universal US screening for DDH. The only inclusion criterion was an adjusted age between 4 and 12 weeks when US was realized. PFD measurement was made using the Couture and Tréguier method. In addition, thicknesses of pubic cartilage and pulvinar were measured on the same US section, in millimeters.
RESULTS
Nine hundred and forty-eight patients, representing 1896 hips, were included. The average value of pubic cartilage thickness was 1.25 mm ± 0.58 mm, with an upper threshold of 2.39 mm (+1.96σ). The average value of pulvinar thickness was 2.67 mm ± 0.78 mm, with an upper threshold of 4.20 mm (+1.96σ). We found high inter-observer reproducibility in pubic cartilage measurements.
CONCLUSION
Systematic measurements of pubic cartilage and pulvinar may refine therapeutic decision by identifying false positives. Patients with increased PFD due to a thick pubic cartilage >2,39 mm, without an associated pulvinar enlargement (<4,20 mm), could be therefore only monitored and not overtreated.
Topics: Cartilage; Developmental Dysplasia of the Hip; Hip Dislocation, Congenital; Humans; Infant; Infant, Newborn; Prospective Studies; Pulvinar; Reproducibility of Results; Ultrasonography
PubMed: 33930718
DOI: 10.1016/j.ejrad.2021.109727 -
Frontiers in Behavioral Neuroscience 2021One important aspect for managing social interactions is the ability to perceive and respond to facial expressions rapidly and accurately. This ability is highly...
One important aspect for managing social interactions is the ability to perceive and respond to facial expressions rapidly and accurately. This ability is highly dependent upon intact processing within both cortical and subcortical components of the early visual pathways. Social cognitive deficits, including face emotion recognition (FER) deficits, are characteristic of several neuropsychiatric disorders including schizophrenia (Sz) and autism spectrum disorders (ASD). Here, we investigated potential visual sensory contributions to FER deficits in Sz ( = 28, 8/20 female/male; age 21-54 years) and adult ASD ( = 20, 4/16 female/male; age 19-43 years) participants compared to neurotypical ( = 30, 8/22 female/male; age 19-54 years) controls using task-based fMRI during an implicit static/dynamic FER task. Compared to neurotypical controls, both Sz ( = 1.97) and ASD ( = 1.13) participants had significantly lower FER scores which interrelated with diminished activation of the superior temporal sulcus (STS). In Sz, STS deficits were predicted by reduced activation of early visual regions ( = 0.85, = 0.002) and of the pulvinar nucleus of the thalamus ( = 0.44, = 0.042), along with impaired cortico-pulvinar interaction. By contrast, ASD participants showed patterns of increased early visual cortical ( = 1.03, = 0.001) and pulvinar ( = 0.71, = 0.015) activation. Large effect-size structural and histological abnormalities of pulvinar have previously been documented in Sz. Moreover, we have recently demonstrated impaired pulvinar activation to simple visual stimuli in Sz. Here, we provide the first demonstration of a disease-specific contribution of impaired pulvinar activation to social cognitive impairment in Sz.
PubMed: 35237135
DOI: 10.3389/fnbeh.2021.787383 -
Frontiers in Cellular Neuroscience 2021Two types of corticothalamic (CT) terminals reach the pulvinar nucleus of the thalamus, and their distribution varies according to the hierarchical level of the cortical...
Two types of corticothalamic (CT) terminals reach the pulvinar nucleus of the thalamus, and their distribution varies according to the hierarchical level of the cortical area they originate from. While type 2 terminals are more abundant at lower hierarchical levels, terminals from higher cortical areas mostly exhibit type 1 axons. Such terminals also evoke different excitatory postsynaptic potential dynamic profiles, presenting facilitation for type 1 and depression for type 2. As the pulvinar is involved in the oscillatory regulation between intercortical areas, fundamental questions about the role of these different terminal types in the neuronal communication throughout the cortical hierarchy are yielded. Our theoretical results support that the co-action of the two types of terminals produces different oscillatory rhythms in pulvinar neurons. More precisely, terminal types 1 and 2 produce alpha-band oscillations at a specific range of connectivity weights. Such oscillatory activity is generated by an unstable transition of the balanced state network's properties that it is found between the quiescent state and the stable asynchronous spike response state. While CT projections from areas 17 and 21a are arranged in the model as the empirical proportion of terminal types 1 and 2, the actions of these two cortical connections are antagonistic. As area 17 generates low-band oscillatory activity, cortical area 21a shifts pulvinar responses to stable asynchronous spiking activity and vice versa when area 17 produces an asynchronous state. To further investigate such oscillatory effects through corticothalamo-cortical projections, the transthalamic pathway, we created a cortical feedforward network of two cortical areas, 17 and 21a, with CT connections to a pulvinar-like network with two cortico-recipient compartments. With this model, the transthalamic pathway propagates alpha waves from the pulvinar to area 21a. This oscillatory transfer ceases when reciprocal connections from area 21a reach the pulvinar, closing the CT loop. Taken together, results of our model suggest that the pulvinar shows a bi-stable spiking activity, oscillatory or regular asynchronous spiking, whose responses are gated by the different activation of cortico-pulvinar projections from lower to higher-order areas such as areas 17 and 21a.
PubMed: 34938163
DOI: 10.3389/fncel.2021.787170 -
Human Brain Mapping Jul 2015The human pulvinar is the largest thalamic area in terms of size and cortical connectivity. Although much is known about regional pulvinar structural anatomy, relatively... (Meta-Analysis)
Meta-Analysis
The human pulvinar is the largest thalamic area in terms of size and cortical connectivity. Although much is known about regional pulvinar structural anatomy, relatively little is known about pulvinar functional anatomy in humans. Cooccurrence of experimentally induced brain activity is a traditional metric used to establish interregional brain connectivity and forms the foundation of functional neuroimaging connectivity analyses. Because functional neuroimaging studies report task-related coactivations within a standardized space, meta-analysis of many whole-brain studies can define the brain's interregional coactivation across many tasks. Such an analysis can also detect and define variations in functional coactivations within a particular region. Here we use coactivation profiles reported in ∼ 7,700 functional neuroimaging studies to parcellate and define the pulvinar's functional anatomy. Parcellation of the pulvinar's coactivation profile identified five clusters per pulvinar of distinct functional coactivation. These clusters showed a high degree of symmetry across hemispheres and correspondence with the human pulvinar's cytoarchitecture. We investigated the functional coactivation profiles of each resultant pulvinar cluster with meta-analytic methods. By referencing existent neuroimaging and lesion-deficit literature, these profiles make a case for regional pulvinar specialization within the larger human attention-controlling network. Reference to this literature also informs specific hypotheses that can be tested in subsequent studies in healthy and clinical populations.
Topics: Brain Mapping; Humans; Nerve Net; Pulvinar
PubMed: 25821061
DOI: 10.1002/hbm.22781 -
World Neurosurgery Feb 2020Thalamic gliomas in children are less suitable for surgical resection because of their location. In cases of unavoidable resection, careful surgical planning in addition...
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.
Topics: Adolescent; Brain Neoplasms; Child; Female; Follow-Up Studies; Glioma; Histones; Humans; Infant; Male; Mutation; Neoplasm Grading; Neoplasm Recurrence, Local; Prognosis; Pulvinar; Retrospective Studies
PubMed: 31704359
DOI: 10.1016/j.wneu.2019.10.116 -
Frontiers in Psychology 2018The processing of emotional stimuli in the absence of awareness has been widely investigated in patients with lesions to the primary visual pathway since the classical...
The processing of emotional stimuli in the absence of awareness has been widely investigated in patients with lesions to the primary visual pathway since the classical studies on affective blindsight. In addition, recent evidence has shown that in hemianopic patients without blindsight only unseen fearful faces can be implicitly processed, inducing enhanced visual encoding (Cecere et al., 2014) and response facilitation (Bertini et al., 2013, 2017) to stimuli presented in their intact field. This fear-specific facilitation has been suggested to be mediated by activity in the spared visual subcortical pathway, comprising the superior colliculus (SC), the pulvinar and the amygdala. This suggests that the pulvinar might represent a critical relay structure, conveying threat-related visual information through the subcortical visual circuit. To test this hypothesis, hemianopic patients, with or without pulvinar lesions, performed a go/no-go task in which they had to discriminate simple visual stimuli, consisting in Gabor patches, displayed in their intact visual field, during the simultaneous presentation of faces with fearful, happy, and neutral expressions in their blind visual field. In line with previous evidence, hemianopic patients without pulvinar lesions showed response facilitation to stimuli displayed in the intact field, only while concurrent fearful faces were shown in their blind field. In contrast, no facilitatory effect was found in hemianopic patients with lesions of the pulvinar. These findings reveal that pulvinar lesions disrupt the implicit visual processing of fearful stimuli in hemianopic patients, therefore suggesting a pivotal role of this structure in relaying fear-related visual information from the SC to the amygdala.
PubMed: 30524351
DOI: 10.3389/fpsyg.2018.02329 -
AJNR. American Journal of Neuroradiology Dec 2017The pulvinar sign refers to exclusive T1WI hyperintensity of the lateral pulvinar. Long considered a common sign of Fabry disease, the pulvinar sign has been reported in...
BACKGROUND AND PURPOSE
The pulvinar sign refers to exclusive T1WI hyperintensity of the lateral pulvinar. Long considered a common sign of Fabry disease, the pulvinar sign has been reported in many pathologic conditions. The exact incidence of the pulvinar sign has never been tested in representative cohorts of patients with Fabry disease. The aim of this study was to assess the prevalence of the pulvinar sign in Fabry disease by analyzing T1WI in a large Fabry disease cohort, determining whether relaxometry changes could be detected in this region independent of the pulvinar sign positivity.
MATERIALS AND METHODS
We retrospectively analyzed brain MR imaging of 133 patients with Fabry disease recruited through specialized care clinics. A subgroup of 26 patients underwent a scan including 2 FLASH sequences for relaxometry that were compared with MRI scans of 34 healthy controls.
RESULTS
The pulvinar sign was detected in 4 of 133 patients with Fabry disease (3.0%). These 4 subjects were all adult men (4 of 53, 7.5% of the entire male population) with renal failure and under enzyme replacement therapy. When we tested for discrepancies between Fabry disease and healthy controls in quantitative susceptibility mapping and relaxometry maps, no significant difference emerged for any of the tested variables.
CONCLUSIONS
The pulvinar sign has a significantly lower incidence in Fabry disease than previously described. This finding, coupled with a lack of significant differences in quantitative MR imaging, allows hypothesizing that selective involvement of the pulvinar is a rare neuroradiologic sign of Fabry disease.
Topics: Adolescent; Adult; Aged; Fabry Disease; Female; Humans; Magnetic Resonance Imaging; Male; Middle Aged; Pulvinar; Retrospective Studies; Young Adult
PubMed: 29051208
DOI: 10.3174/ajnr.A5420