Brachium Pontis


Also another lesion in right brachium pontis which did not contrast enhancement but was hyperintense on T2 and flair images was present.  

Magnetic resonance imaging of the brain revealed distinctive symmetrical T2 high-signal intensities in the bilateral cerebellar hemispheres and brachium pontis, which were consistent with his neurologic deficits.  

Labeled pontocerebellar fibers cross midline and disperse widely in the opposite hemipons before coalescing in the brachium pontis.  

At this time, CT showed areas of coarse calcification in the globi pallidi, left parietal white matter and left brachium pontis.  

The greatest increases were seen in the globus pallidus (14%; P =.002) and brachium pontis (10.8%; P =.003).  

The cerebellum is implicated in the control of CRs and to study whether separate neural pathways were responsible for CR1 and CR2, direct brachium pontis stimulation was used to replace the forelimb CS. CR1 and CR2 were present in the CR elicited by the brachium pontis CS.  

Statistically significant atrophy of pons, brachium pontis, cerebellum and midbrain was noted in patient group.  

We describe a patient with fatal hepatic cirrhosis and AHD in whom MR images showed abnormalities in the brachium pontis bilaterally.  

These deficits were noted to correlate with the presence of edema within the brachium pontis bilaterally, although this association was not absolute.  

Axons of all neurons coursed under NRTP and entered brachium pontis without having synapsed in the brain stem.  

Twenty-six of the DVA caputs were frontal, 16 were parietal, 13 were in the brachium pontis/dentate, seven were in the temporal lobe, three were in the cerebellar hemisphere, three were in the occipital lobe, three were in the basal ganglia, and one was in the pons. CONCLUSION: The DVA caputs and their draining veins occurred in typical locations that could be predicted from the normal medullary venous anatomy, with the frontal, parietal, and brachium pontis/dentate being the most common locations.  

A detailed radiological review of these cases in parallel with 24 cases of vermian tumors without mutism identified only one factor that was significantly associated with the mutism syndrome, bilateral edema within the brachium pontis (P < 0.01).  

To this end we used a triple combination of (1) retrograde labeling (injection of Fluorogold into the brachium pontis), (2) anterograde labeling [ injection of Dil into cortical areas A17 and Sml(forelimb)], and (3) subsequent intracellular fills of identified projection neurons (Lucifer yellow) in slightly fixed slices of pontine brainstem.  

Cranial computed tomography disclosed an infarction in the right cerebellar hemisphere and brachium pontis.  

Following injections of PHA-L restricted to ventral and medial portions of the BPN, labeled fibers were observed in the brachium pontis, the white matter dorsal to the CN, and to a lesser extent, in the white matter of the parafloccular stalk.  

OPCA patients with severe versus mild-moderate atrophy evaluated by 3 measures, i.e., brainstem, brachium pontis and fourth ventricle ratios, presented few significantly lengthened RT and MT performances.  

Ten of the angiomas were located in the insula and basal ganglia, 2 in the thalamus, 5 in the midbrain, 8 in the pons, and 1 in the brachium pontis.  

At the same time, the HRP "in vitro" technique permitted the study of the axonal profiles of the NRTP neurons within the pons until reaching the brachium pontis. Our observations confirm: i) A symmetrical organization of the NRTP-cerebellar projection, the number and location of ipsi- and contralateral NRTP neurons being very similar in all cases; ii) The only exception is represented by the rostralmost portions of the NRTP, in which the neurons show a cluster-complementary pattern; iii) The axons of the NRTP neurons cross the pontine midline at the dorsalmost aspect of the BPN, occupying a medial location within the brachium pontis..  

To explore the possibility that such neurons were labeled because their axons were transected and injury-filled as they coursed through the BPN injection site to enter the cerebellum via the brachium pontis, a series of rats received complete, bilateral lesions of the brachium pontis followed 30-60 minutes later with multiple, diffuse injections of WGA-HRP (12-16 placements per animal) throughout the cerebellar cortex. In another series of animals, the massive cerebellar WGA-HRP injections were not preceded by brachium pontis lesions. However, when the cerebellar HRP injections were preceded by brachium pontis lesions, each of the cell groups in question continued to exhibit labeled somata in numbers comparable to that observed in the nonlesion cases. This implies that such neurons project to the BPN and the cerebellar cortex and that the axons of these particular neurons do not project to the cerebellum via the brachium pontis..  

Phosphate-activated glutaminase-immunoreactive granular deposits were densely seen in the brachium pontis and restiform body, suggesting the immunolabeling of mossy fibers of passage.  

Complex character of the responses of brachium pontis to stimulation of sensorimotor cortex and pyramidal tract was shown in anesthetized cat. The data obtained support the importance of nucleus of pontine gray proper for mediating cerebral signals to cerebellum via brachium pontis..  

Antidromic activation of the pontine nuclei neurons evoked by stimulation of brachium pontis, brachium conjunctivum (in rare cases), cerebellar central nuclei, pyramidal tract and sensorimotor cerebral cortex was studied in narcotized cats using the intracellular recording technique.  

The basal ganglia-induced effects were abolished upon section of the brachium pontis but not of the restiform body.  

The pontocerebellar pathway in the brachium pontis (BP), is known to convey signals from various cortical and subcortical visual structures to the cerebellum.  

Sparse numbers of labeled fibers appeared to descend into the reticular formation and enter the cerebellum via the brachium pontis.  

In the first series of experiments, HRP was injected into the brachium pontis.  

Only rarely are fibers found in either the restiform body or the brachium pontis.  

In the chronic alcoholism group the measurements of the brachium pontis, the medulla, and the fourth ventricle differed significantly from those of normal controls (p less than 0.05)..  

A case of cystinosis is presented with unusually long survival and with bilateral necrosis, numerous concretions, and extensive demyelination of internal capsule and brachium pontis.  

Normative mean flows (mls/100 g brain/min) were: basal ganglia = 79.6 +/- 9.3, cortex = 82.3 +/- 8.5, white matter = 29.2 +/- 5.9, midbrain tegmentum = 94.3 +/- 14.8, cerebellar cortex = 80.1 +/- 10.9, dorsal pons = 89.3 +/- 4.7, brachium pontis = 35.0 +/- 4.2.  

Based on the clinical and neuropathological findings, it was suggested that dissociated vertical (oblique and upbeat) nystagmus in a patient in coma can be caused by bilateral lesions in the brachium pontis..  

The size of the N2 wave from contralateral cerebral cortex is reduced to about half of the original size after electrolytic lesion of either the brachium pontis (BP) or the restiform body (RB) ipsilateral to the recording site, while only a small reduction in the size of N2 is observed after lesions of contralateral BP and RB.  

The fourth angioma was in the brachium pontis and reached to the Flocculus and Loculus quadrangularis inferior.  

Stimulation of the cerebellar nuclear regions or the brachium pontis induced an antidromic action potential composed of IS-SD spikes, after-depolarization and after-hyperpolarization.  

Similar responses were occasionally seen following stimulation of the brachium pontis (BP).  

The region of the orbitofrontal cortex is not represented in the caudal part of the reticular formation, the basotemporal cortex has no projections into brachium pontis..  

This finding is confirmed by the results of anatomical studies in which degenerating fibers were found in the molecular layer (using the Nauta technique) after lesion of the brachium pontis but not after lesions of the medial portion of the pons.  

Dissection and radiography of 32 injected human cerebella show that AICA and its major branches define the position of the pontomedullary sulcus; supra-olivary fossette; 5th-11th cranial nerves; brachium pontis; flocculus; great horizontal fissure; posterolateral fissure; superior semilunar lobule; inferior semilunar lobule; biventral lobule; foramen of Luschka; and the choroid plexus of the lateral recess of the 4th ventricle.  

The lesion had specific predilection sites, such as the white matter around the lateral ventricles, the optic tracts plus chiasm, the pyramidal tracts and the brachium pontis.  

The tentorial branches, originating from the cavernous portion of the internal carotid artery, showed pathological findings in two cases of brain tumors infiltrating the tentorium: a glioblastoma multiforme of the temporooccipital and basal regions and a medulloblastoma diffusely involving the cerebellar hemisphere, vermis brachium pontis and pons.  

PN cells were identified by antidromic invasion from the cerebellum by stimulating either the brachium pontis (BP) or the white matter near the cerebellar nuclei.  

After stimulating the subcortical white matter, the internal capsule or the cerebral peduncle, mass potentials were recorded from the cut end of fibres in the brachium pontis (BP) and in the pyramid at the level of the trapezoid body.  

In extracellular unitary study, out of 107 PN neurones identified by antidromic activation due to the brachium pontis stimulation, 33 responded with firings to stimulation of the parietal association area and 64 to the frontal motor area.  

Out of ninety-one PN neurones (identified as ponto-cerebellas neurones by antidromic stimulation of the contralateral brachium pontis), fifty-seven neurones were influenced by stimulation of at least one cortical site. The distribution of latencies to both cortical and brachium pontis stimulation indicates that the PN are a relay for fast and slow cerebro-cerebellar connexions.  


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