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Proceedings of the National Academy of... Dec 2023The rhombicbrain (rhombencephalon or intermediate sector) is the vertebrate central nervous system part between the forebrain-midbrain (rostral sector) and spinal cord...
The rhombicbrain (rhombencephalon or intermediate sector) is the vertebrate central nervous system part between the forebrain-midbrain (rostral sector) and spinal cord (caudal sector), and it has three main divisions: pons, cerebellum, and medulla. Using a data-driven approach, here we examine intrinsic rhombicbrain (intrarhombicbrain) network architecture that in rat consists of 52,670 possible axonal connections between 230 gray matter regions (115 bilaterally symmetrical pairs). Our analysis indicates that only 8,089 (15.4%) of these connections exist. Multiresolution consensus cluster analysis yields a nested hierarchy model of rhombicbrain subsystems that at the top level are associated with 1) the cerebellum and vestibular nuclei, 2) orofacial-pharyngeal-visceral integration, and 3) auditory connections; the bottom level has 68 clusters, ranging in size from 2 to 11 regions. The model provides a basis for functional hypothesis development and interrogation. More granular network analyses performed on the intrinsic connectivity of individual and combined main rhombicbrain divisions (pons, cerebellum, medulla, pons + cerebellum, and pons + medulla) demonstrate the mutability of network architecture in response to the addition or subtraction of connections. Clear differences between the structure-function network architecture of the rhombicbrain and forebrain-midbrain are discussed, with a stark comparison provided by the subsystem and small-world organization of the cerebellar cortex and cerebral cortex. Future analysis of the connections within and between the forebrain-midbrain and rhombicbrain will provide a model of brain neural network architecture in a mammal.
Topics: Rats; Animals; Cerebellum; Pons; Prosencephalon; Central Nervous System; Mammals
PubMed: 38109532
DOI: 10.1073/pnas.2313997120 -
Nature Reviews. Neuroscience Aug 2019
Topics: Brain Stem; Raphe Nuclei
PubMed: 31213703
DOI: 10.1038/s41583-019-0199-0 -
Brain and Nerve = Shinkei Kenkyu No... Mar 2024Based on a recent review by Krohn et al, the respiratory center and its regulatory mechanisms are described. Although the respiratory control centers in the medulla and... (Review)
Review
Based on a recent review by Krohn et al, the respiratory center and its regulatory mechanisms are described. Although the respiratory control centers in the medulla and pons ensure rhythmic respiration, maintaining and regulating respiration involves a complex network of peripheral chemoreceptors, vagal nerves, and central chemoreceptors. This review discusses the pathophysiology of respiratory disorders in neuromuscular diseases and evaluation and treatment methods based on the anatomy of the respiratory network.
Topics: Humans; Respiration; Neuromuscular Diseases; Respiratory Insufficiency; Medulla Oblongata; Pons
PubMed: 38514105
DOI: 10.11477/mf.1416202594 -
World Neurosurgery Jul 2023Primary pontine hemorrhage (PPH) is a rare intracranial hemorrhage with a wide range of mortality rate. Predicting the prognosis of PPH is still challenging. Previous...
BACKGROUND
Primary pontine hemorrhage (PPH) is a rare intracranial hemorrhage with a wide range of mortality rate. Predicting the prognosis of PPH is still challenging. Previous prognostic scoring tests have not been widely used due to limited external validation. This study applied machine learning (ML) algorithms to develop predictive models for mortality and prognosis of patients with PPH.
METHODS
Data of patients with PPH were retrospectively reviewed. Seven ML models were used to train and validate for predicting outcomes of PPH including 30-day mortality rate, 30-day, and 90-day functional outcomes. Accuracy, sensitivity, specificity, positive and negative predictive value, F1 score, Brier score, and area under the curve (AUC) of the receiver operating characteristic were calculated. The models with the highest AUC were then selected to evaluate the testing data.
RESULTS
One hundred and fourteen patients with PPH were included. Mean hematoma volume was 7 ml and most patients had hematoma in the central part of the pons. The 30-day mortality rate was 34.2% and favorable outcomes were observed in 71.1% and 70.2% during 30-day and 90-day follow-up. The ML model could predict 30-day mortality with an AUC of 0.97 using an artificial neural network. Regarding functional outcome, the gradient boosting machine could predict both 30-day and 90-day outcomes with an AUC of 0.94.
CONCLUSIONS
ML algorithms achieved a high performance and accuracy in predicting PPH outcomes. Despite the need for further validation, ML models are promising tools for clinical applications in the future.
Topics: Humans; Retrospective Studies; Pons; Cerebral Hemorrhage; Machine Learning; Hematoma
PubMed: 37172714
DOI: 10.1016/j.wneu.2023.05.014 -
Neuroreport Apr 2021However, whether the whole-brain functional network hub changes occur in diabetic retinopathy patients remains unknown.
BACKGROUND
However, whether the whole-brain functional network hub changes occur in diabetic retinopathy patients remains unknown.
PURPOSE
The purpose of the study was to investigate the function network centrality and connectivity changes in diabetic retinopathy patients using the voxel-wise degree centrality method.
MATERIALS AND METHODS
Thirty-four diabetic retinopathy patients (18 male and 16 female) and 38 healthy controls (18 male and 20 female) closely matched in age, sex, and education were enrolled in the study. Graph theory-based network analysis was performed to investigate the degree centrality between two groups.
RESULTS
Compared with healthy controls, diabetic retinopathy patients had significantly higher degree centrality values in the pons and bilateral caudate and had significantly lower degree centrality values in the left lingual and right lingual, and right angular/middle occipital gyrus (MOG). Moreover, diabetic retinopathy patients exhibited increased functional connectivity between the bilateral lingual and right cerebellum lobe and right fusiform/bilateral caudate and increased functional connectivity between the right angular/MOG and bilateral anterior cingulum and right cuneus/bilateral precuneus and increased functional connectivity between the bilateral caudate and right lingual and right superior occipital gyrus. In contrast, diabetic retinopathy patients showed decreased functional connectivity between bilateral lingual and left lingual and right lingual and left superior occipital gyrus and decreased functional connectivity between the angular/MOG and right inferior occipital gyrus/right fusiform and left MOG/inferior occipital gyrus and decreased functional connectivity between the bilateral caudate and bilateral cerebellum crus1.
CONCLUSION
Our results highlight that reorganization of the hierarchy of the cortical connectivity network related to visual network.
Topics: Brain; Case-Control Studies; Caudate Nucleus; Cerebellum; Diabetic Retinopathy; Female; Functional Neuroimaging; Humans; Magnetic Resonance Imaging; Male; Middle Aged; Neural Pathways; Occipital Lobe; Parietal Lobe; Pons; Temporal Lobe; Visual Pathways
PubMed: 33657077
DOI: 10.1097/WNR.0000000000001620 -
Anatomical Record (Hoboken, N.J. : 2007) Oct 2019One of the major causes of nocturia is overactive bladder (OAB). Somatic afferent nerve stimuli are used for treating OAB. However, clinical evidence for the efficacy of... (Review)
Review
One of the major causes of nocturia is overactive bladder (OAB). Somatic afferent nerve stimuli are used for treating OAB. However, clinical evidence for the efficacy of this treatment is insufficient due to the lack of appropriate control stimuli. Studies on anesthetized animals, which eliminate emotional factors and placebo effects, have demonstrated an influence of somatic stimuli on urinary bladder functions and elucidated the underlying mechanisms. In general, the effects of somatic stimuli are dependent on the modality, location, and physical characteristics of the stimulus. Recently we showed that gentle stimuli applied to the perineal skin using a soft elastomer roller inhibited micturition contractions to a greater extent than a roller with a hard surface. Studies aiming to elucidate the neural mechanisms of gentle stimulation-induced inhibition reported that 1-10 Hz discharges of low-threshold cutaneous mechanoreceptive Aβ, Aδ, and C fibers evoked during stimulation with an elastomer roller inhibited the micturition reflex by activating the spinal cord opioid system, thereby reducing both ascending and descending transmission between bladder and pontine micturition center. The present review will provide a brief summary of (1) the effect of somatic electrical stimulation on the micturition reflex, (2) the effect of gentle mechanical skin stimulation on the micturition reflex, (3) the afferent, efferent, and central mechanisms underlying the effects of gentle stimulation, and (4) a translational clinical study demonstrating the efficacy of gentle skin stimuli for treating nocturia in the elderly with OAB by using the two roller types inducing distinct effects on rat micturition contractions. Anat Rec, 302:1824-1836, 2019. © 2019 American Association for Anatomy.
Topics: Afferent Pathways; Animals; Disease Models, Animal; Efferent Pathways; Humans; Muscle Contraction; Nocturia; Perineum; Pons; Rats; Skin; Touch; Transcutaneous Electric Nerve Stimulation; Treatment Outcome; Urinary Bladder; Urinary Bladder, Overactive
PubMed: 30980505
DOI: 10.1002/ar.24135 -
Acta Neurochirurgica Mar 2022The horizontal fissure approach is a workhorse for brainstem lesions in the central and dorsolateral pons and middle cerebellar peduncle (MCP). The cerebellopontine...
BACKGROUND
The horizontal fissure approach is a workhorse for brainstem lesions in the central and dorsolateral pons and middle cerebellar peduncle (MCP). The cerebellopontine fissure is a V-shaped fissure with a superior and inferior limb between the cerebellum, pons, and MCP. The horizontal or petrosal fissure is at the apex of the cerebellopontine fissure and extends laterally to divide the petrosal surface of the cerebellum into superior and inferior parts. Splitting this fissure exposes the posterolateral aspect of the MCP without excessive retraction or transgression of the cerebellum.
METHOD
We demonstrate and describe the horizontal fissure operative approach to the middle cerebellar peduncle for resection of a pontine cavernoma with illustrative figures and operative video.
CONCLUSION
Splitting the horizontal (petrosal) fissure of the cerebellum brings the middle cerebellar peduncle into view behind the root entry zone of the trigeminal nerve, providing an expanded, safe corridor to the central and dorsolateral pons.
Topics: Cerebellum; Hemangioma, Cavernous; Humans; Middle Cerebellar Peduncle; Pons; Trigeminal Nerve
PubMed: 34643805
DOI: 10.1007/s00701-021-05015-7 -
Acta Radiologica (Stockholm, Sweden :... Aug 2022The morphological changes in the pons and cerebellum of neonates experiencing profound asphyxia in the early period of life remain to be clarified.
BACKGROUND
The morphological changes in the pons and cerebellum of neonates experiencing profound asphyxia in the early period of life remain to be clarified.
PURPOSE
To assess the changes in the size of the pons and cerebellum during the first two weeks of life in term neonates with pontine and cerebellar injury caused by hypoxic-ischemic encephalopathy in comparison with a control group.
MATERIAL AND METHODS
Two groups were investigated: a group with pontine/cerebellar injury (PCI) (n = 10) demonstrated by magnetic resonance imaging (MRI) diffusion-weighted imaging; and a control group without PCI - focal-multifocal white matter injury and a normal pattern (n = 24). The anteroposterior diameter (APD) and height of the pons and cerebellar vermis, and the transverse width of the cerebellum were measured twice in the first and second weeks of life. Differences between the groups were analyzed statistically using paired and unpaired Student's t-test at a significance level of < 0.05.
RESULTS
In the PCI group, the pontine APD and cerebellar vermian height were significantly decreased in the second week. An increase of pons and cerebellar size was evident during the first two weeks of life in the control groups.
CONCLUSION
Infants with PCI and profound asphyxia show rapid decreases in pontine APD and cerebellar vermian height within the first two weeks of life.
Topics: Asphyxia; Cerebellum; Diffusion Magnetic Resonance Imaging; Humans; Infant; Infant, Newborn; Magnetic Resonance Imaging; Pons
PubMed: 34259022
DOI: 10.1177/02841851211030777 -
Journal of Neurosurgery Jan 2023Medullary cavernous malformations are the least common of the brainstem cavernous malformations (BSCMs), accounting for only 14% of lesions in the authors' surgical...
OBJECTIVE
Medullary cavernous malformations are the least common of the brainstem cavernous malformations (BSCMs), accounting for only 14% of lesions in the authors' surgical experience. In this article, a novel taxonomy for these lesions is proposed based on clinical presentation and anatomical location.
METHODS
The taxonomy system was applied to a large 2-surgeon experience over a 30-year period (1990-2019). Of 601 patients who underwent microsurgical resection of BSCMs, 551 were identified who had the clinical and radiological information needed for inclusion. These 551 patients were classified by lesion location: midbrain (151 [27%]), pons (323 [59%]), and medulla (77 [14%]). Medullary lesions were subtyped on the basis of their predominant surface presentation. Neurological outcomes were assessed according to the modified Rankin Scale (mRS), with an mRS score ≤ 2 defined as favorable.
RESULTS
Five distinct subtypes were defined for the 77 medullary BSCMs: pyramidal (3 [3.9%]), olivary (35 [46%]), cuneate (24 [31%]), gracile (5 [6.5%]), and trigonal (10 [13%]). Pyramidal lesions are located in the anterior medulla and were associated with hemiparesis and hypoglossal nerve palsy. Olivary lesions are found in the anterolateral medulla and were associated with ataxia. Cuneate lesions are located in the posterolateral medulla and were associated with ipsilateral upper-extremity sensory deficits. Gracile lesions are located outside the fourth ventricle in the posteroinferior medulla and were associated with ipsilateral lower-extremity sensory deficits. Trigonal lesions in the ventricular floor were associated with nausea, vomiting, and diplopia. A single surgical approach was preferred (> 90% of cases) for each medullary subtype: the far lateral approach for pyramidal and olivary lesions, the suboccipital-telovelar approach for cuneate lesions, the suboccipital-transcisterna magna approach for gracile lesions, and the suboccipital-transventricular approach for trigonal lesions. Of these 77 patients for whom follow-up data were available (n = 73), 63 (86%) had favorable outcomes and 67 (92%) had unchanged or improved functional status.
CONCLUSIONS
This study confirms that the constellation of neurological signs and symptoms associated with a hemorrhagic medullary BSCM subtype is useful for defining the BSCM clinically according to a neurologically recognizable syndrome at the bedside. The proposed taxonomical classifications may be used to guide the selection of surgical approaches, which may enhance the consistency of clinical communications and help improve patient outcomes.
Topics: Humans; Neurosurgical Procedures; Hemangioma, Cavernous, Central Nervous System; Medulla Oblongata; Pons; Fourth Ventricle
PubMed: 35594887
DOI: 10.3171/2022.3.JNS22626 -
The Journal of Neuroscience : the... Jun 2021Coordination of skilled movements and motor planning relies on the formation of regionally restricted brain circuits that connect cortex with subcortical areas during...
Coordination of skilled movements and motor planning relies on the formation of regionally restricted brain circuits that connect cortex with subcortical areas during embryonic development. Layer 5 neurons that are distributed across most cortical areas innervate the pontine nuclei (basilar pons) by protrusion and extension of collateral branches interstitially along their corticospinal extending axons. Pons-derived chemotropic cues are known to attract extending axons, but molecules that regulate collateral extension to create regionally segregated targeting patterns have not been identified. Here, we discovered that and are expressed in the cortex and the basilar pons in a region-specific and mutually exclusive manner, and that their repulsive activities are essential for segregating collateral extensions from corticospinal axonal tracts in mice. Specifically, and forward and reverse inhibitory signals direct collateral extension such that -positive frontal and occipital cortical areas extend their axon collaterals into the -negative rostral part of the basilar pons, whereas -positive parietal cortical areas extend their collaterals into the -negative caudal part of the basilar pons. Together, our results provide a molecular basis that explains how the corticopontine projection connects multimodal cortical outputs to their subcortical targets. Our findings put forward a model in which region-to-region connections between cortex and subcortical areas are shaped by mutually exclusive molecules to ensure the fidelity of regionally restricted circuitry. This model is distinct from earlier work showing that neuronal circuits within individual cortical modalities form in a topographical manner controlled by a gradient of axon guidance molecules. The principle that a shared molecular program of mutually repulsive signaling instructs regional organization-both within each brain region and between connected brain regions-may well be applicable to other contexts in which information is sorted by converging and diverging neuronal circuits.
Topics: Animals; Axon Guidance; Ephrin-A5; Female; Male; Mice; Mice, Inbred C57BL; Neocortex; Neural Pathways; Pons; Receptor, EphA7
PubMed: 33906900
DOI: 10.1523/JNEUROSCI.0367-20.2021