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Journal of Neurosurgery May 2016OBJECT Brainstem surgery remains a challenge for the neurosurgeon despite recent improvements in neuroimaging, microsurgical techniques, and electrophysiological... (Review)
Review
OBJECT Brainstem surgery remains a challenge for the neurosurgeon despite recent improvements in neuroimaging, microsurgical techniques, and electrophysiological monitoring. A detailed knowledge of the microsurgical anatomy of the brainstem surface and its internal architecture is mandatory to plan appropriate approaches to the brainstem, to choose the safest point of entry, and to avoid potential surgical complications. METHODS An extensive review of the literature was performed regarding the brainstem surgical approaches, and their correlations with the pertinent anatomy were studied and illustrated through dissection of human brainstems properly fixed with 10% formalin. The specimens were dissected using the fiber dissection technique, under ×6 to ×40 magnification. 3D stereoscopic photographs were obtained (anaglyphic 3D) for better illustration of this study. RESULTS The main surgical landmarks and their relationship with the cerebellum and vascular structures were identified on the surface of the brainstem. The arrangements of the white matter (ascending and descending pathways as well as the cerebellar peduncles) were demonstrated on each part of the brainstem (midbrain, pons, and medulla oblongata), with emphasis on their relationships with the surface. The gray matter, constituted mainly by nuclei of the cranial nerves, was also studied and illustrated. CONCLUSIONS The objective of this article is to review the microsurgical anatomy and the surgical approaches pertinent to the brainstem, providing a framework of its external and internal architecture to guide the neurosurgeon during its related surgical procedures.
Topics: Brain Stem; Cerebellum; Cranial Nerves; Humans; Imaging, Three-Dimensional; Medulla Oblongata; Mesencephalon; Microsurgery; Neural Pathways; Photogrammetry; Pons; Reference Values
PubMed: 26517774
DOI: 10.3171/2015.4.JNS132778 -
Neurosurgical Review Jun 2022A better understanding of the surgical anatomy of the cerebellar peduncles in different surgical approaches and their relationship with other neural structures are...
A better understanding of the surgical anatomy of the cerebellar peduncles in different surgical approaches and their relationship with other neural structures are delineated through cadaveric dissections. We aimed to revisit the surgical anatomy of the cerebellar peduncles to describe their courses along the brain stem and the cerebellum and revise their segmental classification in surgical areas exposed through different approaches. Stepwise fiber microdissection was performed along the cerebellar tentorial and suboccipital surfaces. Multiple surgical approaches in each of the cerebellar peduncles were compared in eight silicone-injected cadaveric whole heads to evaluate the peduncular exposure areas. From a neurosurgical point of view, the middle cerebellar peduncle (MCP) was divided into a proximal cisternal and a distal intracerebellar segments; the inferior cerebellar peduncle (ICP) into a ventricular segment followed by a posterior curve and a subsequent intracerebellar segment; the superior cerebellar peduncle (SCP) into an initial congregated, an intermediate intraventricular, and a distal intramesencephalic segment. Retrosigmoid and anterior petrosectomy approaches exposed the junction of the MCP segments; telovelar, supratonsillar, and lateral ICP approaches each reached different segments of ICP; paramedian supracerebellar infratentorial, suboccipital transtentorial, and combined posterior transpetrosal approaches displayed the predecussation SCP within the cerbellomesencephalic fissure, whereas the telovelar approach revealed the intraventricular SCP within the superolateral recess of the fourth ventricle. Better understanding of the microsurgical anatomy of the cerebellar peduncles in various surgical approaches and their exposure limits constitute the most critical aspect for the prevention of surgical morbidity during surgery in and around the pons and the upper medulla. Our findings help in evaluating radiological data and planning an operative procedure for cerebellar peduncles.
Topics: Brain Stem; Cadaver; Cerebellum; Fourth Ventricle; Humans; Pons
PubMed: 34997381
DOI: 10.1007/s10143-021-01701-3 -
Medicine Mar 2023Chronic lymphocytic inflammation with pontine perivascular enhancement responsive to steroids (CLIPPERS) is still a rare autoimmune disease in the world. In recent... (Review)
Review
Chronic lymphocytic inflammation with pontine perivascular enhancement responsive to steroids (CLIPPERS) is still a rare autoimmune disease in the world. In recent years, there are more and more reports about the clinical manifestations of CLIPPERS, but the specific etiology and pathogenesis are not clear. In this paper, by collating the literature reported in recent years, in the reported effective treatment cases, we found the current hypothesis about the pathogenesis of CLIPPERS. Three pathogenesis hypotheses: organ-specific autoimmunity; virus infection affects autoimmunity; and helper T lymphocyte 17 mediates autoimmunity. Although it is hypothetical, it is expected to further clarify the pathogenesis, evolution characteristics, and treatment of CLIPPERS, so as to provide a reference for further understanding of the disease. In the future, more observations and studies are needed to further verify the feasibility of the hypothesis. This article expands on atypical clinical manifestations and summarizes treatment options. Hope to provide a reference for clinical diagnosis and treatment of CLIPPERS.
Topics: Humans; Magnetic Resonance Imaging; Inflammation; Steroids; Treatment Outcome; Pons
PubMed: 36930124
DOI: 10.1097/MD.0000000000033211 -
Acta Neurologica Belgica Mar 2018We aimed to evaluate the differences between apparent diffusion coefficient (ADC), fractional anisotropy (FA), axial diffusivity (AD), and radial diffusivity (RD) values...
We aimed to evaluate the differences between apparent diffusion coefficient (ADC), fractional anisotropy (FA), axial diffusivity (AD), and radial diffusivity (RD) values obtained from different cranial sites in subjects with Chiari I Malformation (CM-I) and borderline tonsillar ectopia (BTE), and to determine correlations between diffusion tensor imaging (DTI) metrics and the severity of tonsillar ectopia. A total of 73 subjects with CM-I and BTE and 35 control underwent MRI and DTI. In our study, ADC values measured from the level of medulla oblongata and the RD values measured in middle cerebellar peduncles, thalamus, and globus pallidus were higher in CM-I patients than in controls. FA values at the medulla oblongata level and AD values at the medulla oblongata and pons level higher in patients with CM-I. ADC and AD values measured at the pons level were higher in BTE subjects than in controls. Compared with BTE, the CM-I subjects' ADC values at the medulla oblongata and AD values at the pons level were higher. In addition, FAs at the pons and medulla oblongata level were higher. At the medulla oblongata level, a positive correlation was observed between ADC and the size of tonsillar ectopia. AD and FA values measured at the level of medulla oblongata and pons were positively correlated with the size of tonsillar ectopia. These findings may be related to the severity of microstructural changes involving neuronal tracts at the brainstem level due to tonsillar ectopia. DTI may be useful in determining the extent of microstructural changes at the tissue level in subjects with tonsillar ectopia.
Topics: Adolescent; Adult; Arnold-Chiari Malformation; Cerebellum; Diffusion Tensor Imaging; Female; Humans; Male; Medulla Oblongata; Pons; Young Adult
PubMed: 28516323
DOI: 10.1007/s13760-017-0792-9 -
Acta Radiologica (Stockholm, Sweden :... Oct 2020Perinatal hypoxic-ischemic encephalopathy (HIE) is a major cause of death and disability in infants. Magnetic resonance imaging (MRI) is valuable for predicting the...
BACKGROUND
Perinatal hypoxic-ischemic encephalopathy (HIE) is a major cause of death and disability in infants. Magnetic resonance imaging (MRI) is valuable for predicting the outcome in high-risk neonates. The relationship of pontine and cerebellar injury to outcome has not been explored sufficiently.
PURPOSE
To characterize MRI features of pontine and cerebellar injury and to assess the clinical outcomes of these neonates.
MATERIAL AND METHODS
The retrospective study included 59 term neonates (25 girls) examined by MRI using 1.5-T scanner in the first two weeks of life between 2008 and 2017. Involvement of the pons and cerebellum was judged as a high signal intensity on diffusion-weighted image (DWI) and a restricted diffusion on an apparent diffusion coefficient (ADC) map.
RESULTS
Pontine involvement was observed in the dorsal portion of pons in eight neonates and cerebellar involvement was observed in dentate nucleus (n = 8), cerebellar vermis (n = 3), and hemisphere (n = 1) in 11 neonates. Combined pontine and cerebellar involvement was observed in eight neonates and only cerebellar involvement in three. The pontine and cerebellar injuries were always associated with very severe brain injury including a basal ganglia/thalamus injury pattern and a total brain injury pattern. In terms of clinical outcome, all but four lost to follow-up, had severe cerebral palsy.
CONCLUSION
Pontine and cerebellar involvement occurred in the dorsal portion of pons and mostly dentate nucleus and was always associated with a more severe brain injury pattern as well as being predictive of major disability.
Topics: Cerebellum; Diffusion Magnetic Resonance Imaging; Female; Humans; Hypoxia-Ischemia, Brain; Infant, Newborn; Magnetic Resonance Imaging; Male; Pons
PubMed: 31979976
DOI: 10.1177/0284185119900442 -
Proceedings of the National Academy of... Feb 2024Neuropeptide S (NPS) was postulated to be a wake-promoting neuropeptide with unknown mechanism, and a mutation in its receptor (NPSR1) causes the short sleep duration...
Neuropeptide S (NPS) was postulated to be a wake-promoting neuropeptide with unknown mechanism, and a mutation in its receptor (NPSR1) causes the short sleep duration trait in humans. We investigated the role of different NPS nuclei in sleep/wake regulation. Loss-of-function and chemogenetic studies revealed that NPS neurons in the parabrachial nucleus (PB) are wake-promoting, whereas peri-locus coeruleus (peri-LC) NPS neurons are not important for sleep/wake modulation. Further, we found that a NPS nucleus in the central gray of the pons (CGPn) strongly promotes sleep. Fiber photometry recordings showed that NPS neurons are wake-active in the CGPn and wake/REM-sleep active in the PB and peri-LC. Blocking NPS-NPSR1 signaling or knockdown of supported the function of the NPS-NPSR1 pathway in sleep/wake regulation. Together, these results reveal that NPS and NPS neurons play dichotomous roles in sleep/wake regulation at both the molecular and circuit levels.
Topics: Humans; Sleep; Pons; Locus Coeruleus; Neurons; Neuropeptides; Receptors, G-Protein-Coupled
PubMed: 38381789
DOI: 10.1073/pnas.2320276121 -
AJNR. American Journal of Neuroradiology May 2022Imaging biomarkers derived from different brainstem structures are suggested to differentiate among parkinsonian disorders, but clinical implementation requires...
BACKGROUND AND PURPOSE
Imaging biomarkers derived from different brainstem structures are suggested to differentiate among parkinsonian disorders, but clinical implementation requires normative data. The main objective was to establish high-quality, sex-specific data for relevant brainstem structures derived from MR imaging in healthy subjects from the general population in their sixth and seventh decades of life.
MATERIALS AND METHODS
3D T1WI acquired on the same 1.5T scanner of 996 individuals (527 women) between 50 and 66 years of age from a prospective population study was used. The area of the midbrain and pons and the widths of the middle cerebellar peduncles and superior cerebellar peduncles were measured, from which the midbrain-to-pons ratio and Magnetic Resonance Parkinsonism Index [MRPI = (Pons Area / Midbrain Area) × (Middle Cerebellar Peduncles / Superior Cerebellar Peduncles)] were calculated. Sex differences in brainstem measures and correlations to age, height, weight, and body mass index were investigated.
RESULTS
Inter- and intrareliability for measuring the different brainstem structures showed good-to-excellent reliability (intraclass correlation coefficient = 0.785-0.988). There were significant sex differences for the pons area, width of the middle cerebellar peduncles and superior cerebellar peduncles, midbrain-to-pons ratio, and MRPI (all, < .001; Cohen D = 0.44-0.98), but not for the midbrain area (= .985). There were significant very weak-to-weak correlations between several of the brainstem measures and age, height, weight, and body mass index in both sexes. However, no systematic difference in distribution caused by these variables was found, and because age had the highest and most consistent correlations, age-/sex-specific percentiles for the brainstem measures were created.
CONCLUSIONS
We present high-quality, sex-specific data and age-/sex-specific percentiles for the mentioned brainstem measures. These normative data can be implemented in the neuroradiologic work-up of patients with suspected brainstem atrophy to avoid the risk of misdiagnosis.
Topics: Brain Stem; Female; Humans; Magnetic Resonance Imaging; Magnetic Resonance Spectroscopy; Male; Mesencephalon; Parkinson Disease; Parkinsonian Disorders; Pons; Prospective Studies; Reproducibility of Results; Supranuclear Palsy, Progressive
PubMed: 35393362
DOI: 10.3174/ajnr.A7485 -
Central Nervous System Agents in... 2021Cannabidiol (CBD), a non-psychotropic constituent of Cannabis sativa, has shown therapeutic promises by modulating several pathological conditions, including pain,...
Effects on the Post-translational Modification of H3K4Me3, H3K9ac, H3K9Me2, H3K27Me3, and H3K36Me2 Levels in Cerebral Cortex, Hypothalamus and Pons of Rats after a Systemic Administration of Cannabidiol: A Preliminary Study.
BACKGROUND
Cannabidiol (CBD), a non-psychotropic constituent of Cannabis sativa, has shown therapeutic promises by modulating several pathological conditions, including pain, epilepsy autism, among others. However, the molecular mechanism of action of CBD remains unknown and recent data suggest the engagement on CBD´s effects of nuclear elements, such as histone activity.
AIM
This study assessed the changes in the post-translational modification (PTM) on the histones H3K4Me3, H3K9ac, H3K9Me2, H3K27Me3, and H3K36Me2 in several brain regions of rats after the administration of CBD (20 mg/Kg/i.p.).
OBJECTIVE
To evaluate the effects on the PTM of histones H3K4Me3, H3K9ac, H3K9Me2, H3K27Me3, and H3K36Me2 levels in the cerebral cortex, hypothalamus and pons of CBD-treated rats.
METHODS
Ten adult rats were randomly assigned into 2 groups: Control or CBD (20 mg/Kg/i.p). Animals were sacrificed after treatments and brains were collected for dissections of the cerebral cortex, hypothalamus and pons. Samples were analyzed for PTM on the histones H3K4Me3, H3K9ac, H3K9Me2, H3K27Me3, and H3K36Me2 levels by Western blot procedure.
RESULTS
CBD increased the PTM levels on the histones H3K4Me3, H3K9ac, and H3K27Me3 in the cerebral cortex whereas no significant differences were found in H3K9Me2 and H3K36Me2. In addition, in the hypothalamus, CBD decreased the contents of H3K9ac while no significant effects were observed in H3K4Me3, H3K9Me2, H3K27Me3, and H3K36Me2. Lastly, in the pons, CBD- treated rats showed a significant decline on the PTM levels of H3K4Me3 whereas no statistical differences were found in H3K9ac, H3K9Me2, H3K27Me3, and H3K36Me2.
CONCLUSION
The study showed that CBD induced differential effects in levels of PTM on the histones H3K4Me3, H3K9ac, H3K9Me2, H3K27Me3, and H3K36Me2 in several brain regions.
Topics: Animals; Cannabidiol; Cerebral Cortex; Histones; Hypothalamus; Pons; Protein Processing, Post-Translational; Rats
PubMed: 32972354
DOI: 10.2174/1871524920666200924114524 -
Neurology India 2022"Thirteen-and-a-half" is a newly described clinical syndrome characterized by the combination of the one-and-a-half syndrome with fifth and seventh cranial nerve nuclei...
BACKGROUND
"Thirteen-and-a-half" is a newly described clinical syndrome characterized by the combination of the one-and-a-half syndrome with fifth and seventh cranial nerve nuclei involvement (1 + 5 + 7 = 13). To the authors' knowledge, this is the first report of the thirteen-and-a-half syndrome secondary to pontine cavernoma and, overall, only the second reported case of this syndrome in the literature till date.
CASE REPORT
A 20-year-old man presented with the clinical features suggestive of the thirteen-and-a-half syndrome, explained radiologically by pontine cavernoma. We operated him using a suboccipital transvermian approach and he is doing well at 2.5 years follow-up. Interestingly, his one-and-a-half syndrome has partially improved to left horizontal gaze palsy.
CONCLUSION
The clinical appreciation of the thirteen-and-a-half syndrome precisely localizes the lesion to ipsilateral dorsal pontine tegmentum. Neurosurgeons must be aware of the newly described "one-and-a-half- plus" syndromes as they help in a better understanding of pathoanatomy caused by different disease processes in the brainstem.
Topics: Adult; Brain Stem; Hemangioma, Cavernous; Humans; Male; Pons; Strabismus; Syndrome; Young Adult
PubMed: 35263913
DOI: 10.4103/0028-3886.338728 -
Current Neurology and Neuroscience... Jul 2014Over the past several decades, the neural mechanisms underlying REM sleep have become increasingly understood. A more detailed understanding of the respective roles of... (Review)
Review
Over the past several decades, the neural mechanisms underlying REM sleep have become increasingly understood. A more detailed understanding of the respective roles of the pontine nuclei in the generation of REM sleep and its related phenomenon has allowed for the recognition of specific effects that brainstem lesions have on sleep. In humans, however, the effects of such lesions are limited to case reports and small case series. This article offers a comprehensive review of the basic neurobiology of REM sleep. In addition, we discuss specific clinical effects that various pontine lesions have with regard to REM sleep and the spectrum of clinical sleep disorders characterized by abnormalities in REM-related phenomena. We review the existing literature detailing the interactions between clinical sleep manifestations and brainstem pathology.
Topics: Humans; Models, Neurological; Narcolepsy; Neurodegenerative Diseases; Pons; Sleep, REM
PubMed: 24828197
DOI: 10.1007/s11910-014-0460-x