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Neuron May 2023In this issue of Neuron, Xiao et al. reported that inhibitory and excitatory neurons in the pontine central gray encode and transmit opposite valences of sensory...
In this issue of Neuron, Xiao et al. reported that inhibitory and excitatory neurons in the pontine central gray encode and transmit opposite valences of sensory stimuli through parallel circuits to a distributed brain network.
Topics: Pons; Neurons; Pontine Tegmentum; Cerebellar Nuclei
PubMed: 37141860
DOI: 10.1016/j.neuron.2023.04.009 -
Neurosurgery Clinics of North America Jul 1993Advances in imaging have made possible confident diagnosis of infiltrative pontine gliomas without biopsy. When the diagnosis is in doubt, stereotactic biopsy is the... (Review)
Review
Advances in imaging have made possible confident diagnosis of infiltrative pontine gliomas without biopsy. When the diagnosis is in doubt, stereotactic biopsy is the procedure of choice. Surgical intervention is restricted to tumors with a dorsally exophytic component and other rare circumstances.
Topics: Brain Neoplasms; Diagnosis, Differential; Humans; Neurosurgery; Pons
PubMed: 8353450
DOI: No ID Found -
World Neurosurgery Jun 2020In this article, we describe a new safe entry point for the posterolateral pons.
OBJECTIVE
In this article, we describe a new safe entry point for the posterolateral pons.
METHODS
To show the adjacent anatomy and measure the part of the interpeduncular sulcus that can be safely accessed, we first performed a review of the literature regarding the pons anatomy and its surgical approaches. Thereafter, 1 human cadaveric head and 15 (30 sides) human brainstems with attached cerebellums were bilaterally dissected with the fiber microdissection technique. A clinical correlation was made with an illustrative case of a dorsolateral pontine World Health Organization grade I astrocytoma.
RESULTS
The safe distance for accessing the interpeduncular sulcus was found to extend from the caudal end of the lateral mesencephalic sulcus to the point at which the intrapontine segment of the trigeminal nerve crosses the interpeduncular sulcus. The mean distance was 8.2 mm (range, 7.15-8.85 mm). Our interpeduncular sulcus safe entry zone can be exposed through a paramedian infratentorial supracerebellar approach. When additional exposure is required, the superior portion of the quadrangular lobule of the cerebellar hemispheric tentorial surface can be removed. In the presented case, surgical resection of the tumor was performed achieving a gross total resection, and the patient was discharged without neurologic deficit.
CONCLUSIONS
The interpeduncular sulcus safe entry zone provides an alternative direct route for treating intrinsic pathologic entities situated in the posterolateral tegmen of the pons between the superior and middle cerebellar peduncles. The surgical corridor provided by this entry point avoids most eloquent neural structures, thereby preventing surgical complications.
Topics: Humans; Microdissection; Microsurgery; Middle Cerebellar Peduncle; Neurosurgical Procedures; Pons
PubMed: 32217179
DOI: 10.1016/j.wneu.2020.03.084 -
Respiratory Physiology & Neurobiology Nov 2004
Review
Topics: Animals; Humans; Inhalation; Pons; Respiration; Rhombencephalon
PubMed: 15519547
DOI: 10.1016/j.resp.2004.06.007 -
Respiratory Physiology & Neurobiology Feb 2020Neonatal animals are extremely tolerant of hypothermia. However, cooling will ultimately lead to ventilatory arrest, or cessation of respiratory movements. Upon...
Neonatal animals are extremely tolerant of hypothermia. However, cooling will ultimately lead to ventilatory arrest, or cessation of respiratory movements. Upon rewarming, ventilation can recover spontaneously (autoresuscitation). This study examined the effect of age (P0-P5) and the pons on respiratory-related output during hypothermic ventilatory arrest and recovery using a brainstem-spinal cord preparation of neonatal rats. As temperature fell, burst frequency slowed, burst duration increased, burst shape became fragmented and eventually respiratory arrest occurred in all preparations. Removing the pons had little effect on younger preparations (P0-P2). Older preparations (P4-P5) with the pons removed continued to burst at cooler temperatures compared to pons-intact preparations and burst durations were significantly longer. Episodic breathing patterns were observed in all preparations (all ages, pons on or off) at lower temperatures. At 27 °C, however, episodic breathing was only observed in younger preparations with the pons on. These data suggest that developmental changes occurring at the level of the pons underlie the loss of hypothermic tolerance and episodic breathing.
Topics: Age Factors; Animals; Animals, Newborn; Body Temperature Regulation; Hypothermia; Periodicity; Pons; Rats; Rats, Sprague-Dawley; Respiration; Respiratory Burst; Return of Spontaneous Circulation; Spinal Cord
PubMed: 31634578
DOI: 10.1016/j.resp.2019.103333 -
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 -
Pediatric Neurosurgery Dec 1999A very rare case of a pontine hydatid cyst is reported. It was diagnosed preoperatively on the basis of magnetic resonance imaging findings. The patient was operated on... (Review)
Review
A very rare case of a pontine hydatid cyst is reported. It was diagnosed preoperatively on the basis of magnetic resonance imaging findings. The patient was operated on in the sitting position. Total excision of the cyst using the Dowling technique and gravity effect was performed through the floor of the fourth ventricle. The patient was discharged without extra neurological sequel. The significance of an accurate preoperative diagnosis, surgical approaches and technique in the management of this pathology is discussed.
Topics: Child, Preschool; Echinococcosis; Fourth Ventricle; Humans; Magnetic Resonance Imaging; Male; Neurosurgical Procedures; Pons; Preoperative Care; Taeniasis
PubMed: 10702734
DOI: 10.1159/000028884 -
The Kaohsiung Journal of Medical... Feb 2016
Topics: Cerebral Infarction; Female; Humans; Middle Aged; Ocular Motility Disorders; Pons
PubMed: 26944331
DOI: 10.1016/j.kjms.2015.11.001 -
The American Journal of Physiology Aug 1994The mass discharges of the splanchnic sympathetic (SND) and phrenic nerves (PND) were recorded in urethananesthetized rats with resected vagal and aortic nerves. Carotid...
The mass discharges of the splanchnic sympathetic (SND) and phrenic nerves (PND) were recorded in urethananesthetized rats with resected vagal and aortic nerves. Carotid chemoreceptor (CC) stimulation with N2 inhalation (4-12 s) or cyanide (50-100 micrograms/kg iv) activated SND in bursts synchronized with the postinspiratory phase (mean SND increase: 105 +/- 8%), raised AP, and increased PND rate and amplitude (n = 40). Brain transection at superior collicular level produced no effect. The sympathetic (SChR) and respiratory chemoreflexes (RChR) were reduced after transections through the pons. Lesions of the dorsolateral pons (dl-pons) produced CO2-dependent apneusis and/or tachypnea at rest. After such lesions, CC stimulation produced expiratory apnea and a 30% increase in SChR due to tonic activation of SND. In contrast, bilateral lesions of the ventrolateral pons (vl-pons) reduced the SChR by 54-76%. Muscimol (Mus) injections (bilateral, 175 pmol/side) into vl-pons did not change resting SND, MAP, baroreflex, and RChR but reduced the SChR (54-82%). In conclusion, under anesthesia: 1) the pathway of the carotid chemoreflex is confined to the pons and medulla, 2) the dl-pons exerts indirect control over the SChR via its role in respiratory rhythmogenesis, and 3) neurons in the vl-pons contribute selectively to the SChR but not to PND activation during CC activation.
Topics: Animals; Brain Stem; Carotid Arteries; Chemoreceptor Cells; Denervation; Electrophysiology; Injections; Male; Muscimol; Neural Inhibition; Neurons; Pons; Rats; Rats, Sprague-Dawley; Reflex; Sympathetic Nervous System
PubMed: 8067462
DOI: 10.1152/ajpregu.1994.267.2.R508 -
Acta Medica Portuguesa 2010Cerebellar hypoplasias are cerebellar malformations with small but completely formed cerebellum. They can be divided in focal and in diffuse or generalized. It is... (Review)
Review
Cerebellar hypoplasias are cerebellar malformations with small but completely formed cerebellum. They can be divided in focal and in diffuse or generalized. It is sometimes difficult to make distinction between cerebellar atrophy (progressive condition) and hipoplasia (not progressive condition). Focal hypoplasias are restricted to one cerebellar hemisphere or to the vermis. Diffuse hypoplasias refer to both cerebellar hemispheres and vermis. If there is associated IVth ventricle enlargement, hypoplasias occur in the context of Dandy-Walker complex, a continuum of posterior fossa cystic anomalies. A revision of cerebellar hypoplasias and associated pathology is done, illustrated with 22 cases tha include focal and diffuse cerebellar hypoplasias, Dandy-Walker malformations and its variant, persistent Blake's pouch cyst, megacisterna magna, PEHO síndrome (progressive encephalopathy with oedema, hipsarrhythmia and optic atrophy), Joubert syndrome, congenital disorder of glycosylation type Ia, pontocerebellar hipoplasias Barth type I and II, diffuse subcortical heterotopia. The imaging finding of structural cerebellar anomalies frequently leads to diagnostic incertainty as the anomalies are mostly unspecific, implying an extenuating analytical and genetic workup. Their knowledge and classification may be useful to decide the patient adjusted laboratorial workup.
Topics: Abnormalities, Multiple; Cerebellum; Humans; Pons
PubMed: 21144325
DOI: No ID Found