Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “Internal Capsule”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 343 records · Page 19Linked to original sources
PubMed1992

Central pain from cerebral abscess: thalamic syndrome in AIDS patients with toxoplasmosis.

We describe two patients with acquired immunodeficiency syndrome (AIDS) who developed classic thalamic syndrome (TS) due to Toxoplasma abscesses in the thalamic region. Treatment with amitriptyline provided substantial relief in both patients. Postmortem examination in one case revealed a lesion in the internal capsule and thalamic reticular nucleus. These observations indicate that (1) TS can result from an isolated lesion in the internal capsule and reticular nucleus of the thalamus, (2) cerebral abscess can cause classic TS, (3) central pain can be added to the many pain syndromes that afflict AIDS patients, and (4) an analgesic response to amitriptyline is possible in these patients.

Acquired Immunodeficiency Syndrome↗
PubMed1990

[Neuroradiological studies of Wilson's disease by computed tomography and magnetic resonance imaging].

Three cases of Wilson's disease were imaged by computed tomography and magnetic resonance. They were characterized by common findings. CT scan showed atrophy of cerebral cortex, caudate head, midbrain and cerebellum, and areas of low absorption in the caudate head, putamen, globus pallidus, posterior limb of internal capsule, thalamus and midbrain. The T2-weighted MRI imaging demonstrated marked hyperintensity in the putamen, retrolenticular part of internal capsule, thalamus and midbrain. In 2 patients, these high intensity areas were decreased by chelating therapy. Improvement of the increased intensity on T2-weighted images led to the suggestion that the area of marked hyperintensity area might be edema or demyelination rather than neuronal loss or cavitation.

Adolescent↗
PubMedDate not supplied

Regional correlation of PET and CT in senile dementia of the Alzheimer type.

Alzheimer disease is manifested by both widespread and regionally restricted brain changes, some of which have recently been identified in vivo with computed tomography (CT) and positron emission tomography (PET). This is a report of the regional correlation of CT and PET measurements in 19 carefully diagnosed subjects comprising 11 controls and eight patients with senile dementia of the Alzheimer type. Regional CT attenuation values did not discriminate between the two groups, but PET using 18F-2-deoxy-2-fluoro-D-glucose demonstrated significant regional reductions (range, 21%-28%) in glucose utilization in the Alzheimer group. PET measures were also more consistently related to cognitive decline. The correlation between CT structural measures and PET metabolic measures demonstrated consistent relations between widespread PET regions and CT changes in the thalamus, posterior limb of the internal capsule, and temporal lobes. However, CT changes in the frontal white matter, caudate nucleus, and anterior limb of the internal capsule were not related to any regional PET changes. These data support previous findings of temporal lobe involvement in Alzheimer disease and suggest the involvement of structures in the region of the third ventricle.

Aged↗
PubMed1995

Strategic infarcts in vascular dementia. A clinical and brain imaging experience.

The mechanisms of dementia resulting from small deep infarctions are incompletely understood. The thesis underlying the concept of "multi-infarct dementia" is that multiple lesions have a synergistic effect on mental functions, resulting in dementia irrespective of specific location or volume. In this report, we summarize our experience with six patients reported previously along with additional patients examined subsequently, whose clinical features and brain imaging findings allow an alternative formulation for dementia resulting from lacunar stroke. The six initial patients presented with an abrupt change in behavior after acute infarction involving the inferior genu of the internal capsule documented by computed tomography (CT) and magnetic resonance imaging (MRI). The acute syndrome featured fluctuating alertness, inattention, memory loss, apathy, abulia, and psychomotor retardation suggesting frontal lobe dysfunction. Contralateral hemiparesis and dysarthria were generally mild, except when the infarct extended into the posterior limb. Neuropsychological testing in five patients with left-sided infarcts revealed severe verbal memory loss. Additional cognitive deficits consistent with dementia were evident in four patients. A right-sided infarct caused transient impairment in visuospatial memory. Functional brain imaging in three patients using 133xenon regional cerebral blood flow (rCBF) and single photon emission computed tomography (SPECT) showed focal reduction in hemispheric perfusion most prominent in the ipsilateral inferior and medial frontal cortex. Perfusion was also defective in the medial and laterial temporal cortex. Important pathways of the limbic system traverse the inferior capsule in the region of the genu. Corticothalamic and thalamocortical fibers form the thalamic peduncles which detach from the internal capsule and enter the thalamus at its rostral and caudal poles and along its dorsal surface. The anterior thalamic peduncle, conveys reciprocal connections between the dorsomedial nucleus and the cingulate gyrus, as well as the prefrontal and orbitofrontal cortex. The inferior thalamic peduncle carries fibers which connect the thalamus with orbitofrontal, insular, and temporal cortex, as well as the amygdala via the ansa peduncularis to the ventral amygdalofugal pathway. Thus, damage to one or both white-matter tracts may occur with infarctions in the region of the inferior genu, causing striking frontal behavioral effects and memory loss in our patients associated with functional deactivation of the ipsilateral frontal and temporal cortex.(ABSTRACT TRUNCATED AT 400 WORDS)

Cerebral Infarction↗
PubMed2006

[Deep cerebral venous system thrombosis: report of two cases].

We report two cases of cerebral deep venous thrombosis in female adults. The first patient presented with headaches and confusion 20 days postpartum. Deep cerebral internal venous thrombosis was suspected based on the CT scan showing bilateral hypodensity in the thalamus and internal capsules. The diagnosis was confirmed on cerebral angiography. The patient was treated but died within 3 weeks of the onset of symptoms. The second patient had no obvious predisposing factors. She presented with confusion and fever. The diagnosis was strongly suggested by the CT scan, which showed spontaneous high density in the deep venous system associated with bilateral hypodensities in the thalamus and internal capsules. Venous MR angiography revealed obliteration of internal cerebral veins and the great vein of Galen. Ten days after appropriate therapy, the patient recovered completely.

Adult↗
PubMed1998

Distribution of catecholaminergic afferent fibres in the rat globus pallidus and their relations with cholinergic neurons.

The topographical distribution of catecholaminergic nerve fibres and their anatomical relationship to cholinergic elements in the rat globus pallidus were studied. Peroxidase-antiperoxidase and two-colour immunoperoxidase staining procedures were used to demonstrate tyrosine hydroxylase (TH), dopamine beta-hydroxylase (DBH), phenylethanolamine N-methyltransferase (PNMT) and choline acetyltransferase (ChAT) immunoreactivities, combined with acetylcholinesterase (AChE) pharmacohistochemistry. TH immunoreactive nerve fibres were seen to enter the globus pallidus from the medial forebrain bundle. The greatest density of such fibres was found in the ventral region of the globus pallidus, which was also characterized by the greatest density of ChAT immunoreactive neurons. TH immunoreactive nerve fibres showed varicose arborizations and sparse boutons, which were occasionally seen in close opposition to cholinergic structures. In all regions of the globus pallidus, there were also larger, smooth TH immunoreactive nerve fibres of passage to the caudate putamen. A smaller number of DBH immunoreactive nerve fibres and terminal arborizations were found in the substantia innominata, internal capsule and in the globus pallidus bordering these structures. A few PNMT immunoreactive nerve fibres in the substantia innominata and internal capsule did not enter the globus pallidus. Electron microscopy revealed TH immunoreactive synaptic profiles in the ventromedial area of the globus pallidus corresponding to the nucleus basalis magnocellularis of Meynert (nBM). These made mainly symmetrical and only a few asymmetrical synaptic contacts with dendrites containing AChE reaction product. The results indicate that cholinergic structures in the nBM are innervated by dopaminergic fibres and terminals, with only a very small input from noradrenergic fibres.

Acetylcholinesterase↗
PubMed2000

Distribution of SNAP-25 in transient neuronal circuitries of the developing human forebrain.

The distribution of SNAP-25 is demonstrated within prominent transient structures in the developing human forebrain. During early fetal development SNAP-25 is mainly expressed in axons of the intermediate zone and the internal capsule. The fibers appear directed towards the mantle zone of the ganglionic eminence and the perireticular nucleus located within the internal capsule. Cells of these two areas are shown to interact with SNAP-25 immunoreactive structures with the aid of double-labellings. The SNAP-25 immunoreactive fibers may represent corticofugal axons which contact the perireticular nucleus and ganglionic eminence which are regarded as intermediate targets providing a scaffold for growing axons. Anti-SNAP-25, thus, is an appropriate marker of intermediate targets which are involved in brain injuries of preterm infants.

Adult↗
PubMed1984

Painful ataxic hemiparesis.

Right hemiparesis with right-sided pain and ataxia developed in a 68-year-old man. Sensation, neuropsychological function, and somatosensory evoked potentials were normal. Computed tomography showed an isolated fresh infarct in the left part of the thalamus. The pain and ataxic disturbances were related to involvement of the thalamus itself, but the hemiparesis with hyperactive tendon reflexes and Babinski's sign was probably due to associated dysfunction in the adjacent internal capsule from compression or edema. In the available clinicopathological reports of cases with hemiparesis and thalamic infarction, contiguous involvement of the internal capsule or no associated lesion has been reported. Because of the occurrence of pain, which is not present in pontine, mesencephalic, or capsular ataxic hemiparesis, we suggest that the syndrome seen in our patient be called "painful ataxic hemiparesis."

Ataxia↗
PubMed2003

Statistical mapping analysis of lesion location and neurological disability in multiple sclerosis: application to 452 patient data sets.

In multiple sclerosis (MS), the correlation between disability and the volume of white matter lesions on magnetic resonance imaging (MRI) is usually weak. This may be because lesion location also influences the extent and type of functional disability. We applied an automatic lesion-detection algorithm to 452 MRI scans of patients with relapsing-remitting MS to identify the regions preferentially responsible for different types of clinical deficits. Statistical parametric maps were generated by performing voxel-wise linear regressions between lesion probability and different clinical disability scores. There was a clear distinction between lesion locations causing physical and cognitive disability. Lesion likelihood correlated with the Expanded Disability Status Scale (EDSS) in the left internal capsule and in periventricular white matter mostly in the left hemisphere. Pyramidal deficits correlated with only one area in the left internal capsule that was also present in the EDSS correlation. Cognitive dysfunction correlated with lesion location at the grey-white junction of associative, limbic, and prefrontal cortex. Coordination impairment correlated with areas in interhemispheric and pyramidal periventricular white matter tracts, and in the inferior and superior longitudinal fascicles. Bowel and bladder scores correlated with lesions in the medial frontal lobes, cerebellum, insula, dorsal midbrain, and pons, areas known to be involved in the control of micturition. This study demonstrates for the first time a relationship between the site of lesions and the type of disability in large scale MRI data set in MS.

Adult↗
PubMed2001

Expression of 27 kDa heat shock protein (Hsp27) in immature rat brain after a cortical aspiration lesion.

The 27 kDa heat shock protein (Hsp27) is a well-known member of the astroglial response to injury, playing a protective role against oxidative stress, apoptosis, and cytoskeletal destruction. Although several studies have been focused on the damaged adult brain, little is known about Hsp27 expression in the immature brain. In this work, we have examined the spatiotemporal pattern of Hsp27 expression in the normal postnatal rat brain following a cortical aspiration lesion at postnatal day 9. In the immature brain, Hsp27 is mainly observed in the internal capsule, although some scattered cells are also found in the ependyma, the corpus callosum, the septum, and hypothalamic glia limitans. In the internal capsule, Hsp27 expression is developmentally regulated, being significantly decreased from postnatal day 14. After a cortical aspiration lesion, de novo expression of Hsp27 is observed in cortical injured areas as well as in the secondary affected thalamus. In the cortex, expression of Hsp27 is first seen at day 1 postlesion (PL) surrounding the neurodegenerative area, becoming restricted to the glial scar at longer survival times. Although a pulse-like expression of Hsp27 is observed in some microglial cells at day 1 PL, most Hsp27-labeled cells are reactive astrocytes, which show GFAP overexpression and coexpress vimentin from day 3 PL. In the thalamus, astroglial Hsp27 expression is delayed, being first observed at day 5 PL. Thalamic Hsp27-labeled astrocytes do not show vimentin expression. Our observations demonstrate astroglial expression of Hsp27 in areas of tissue damage following postnatal traumatic injury, suggesting an involvement of this cytoskeleton-stabilizing protein in the remodeling processes following postnatal brain damage.

Aging↗
PubMed2005

West Nile virus infection: MR imaging findings in the nervous system.

BACKGROUND AND PURPOSE: West Nile virus (WNV) infection is an ongoing seasonal epidemic. We correlated the MR imaging findings with the clinical presentations and outcomes of WNV infection. METHODS: We reviewed 14 brain and three spinal MR images: nonenhanced and contrast-enhanced T1-weighted images (T1WIs) and T2-weighted images (T2WIs), nonenhanced fluid-attenuated inversion recovery (FLAIR) images (11 patients) and enhanced FLAIR images (three patients), with diffusion-weighted (DW) images and apparent diffusion coefficient maps. WNV infection was diagnosed by means of enzyme-linked immunosorbent assay with a plaque reduction neutralization test. We also correlated the MR findings with the clinical presentation, course, and outcome to determine their prognostic importance. RESULTS: MR imaging findings included: 1) normal (five patients); 2) DW imaging-only abnormalities in the white matter, corona radiata, and internal capsule (four patients); 3) hyperintensity on FLAIR images and T2WIs in the lobar gray and white matter, cerebellum, basal ganglia, thalamus and internal capsule, pons and midbrain (three patients); 4) meningeal involvement (two patients); and 5) spinal cord, cauda equina, and nerve root involvement (three patients). All patients with finding 1 and all but one with finding 2 recovered completely. Two patients with finding 3 died. Those with finding 4 or 5 had residual neurologic deficits that were severe or moderate to severe, respectively. CONCLUSION: Patients with normal MR images or abnormalities on only DW images had the best prognosis, while those with abnormal signal intensity on T2WI and FLAIR images had the worst outcomes. No definite predilection for any specific area of the brain parenchyma was noted.

Adolescent↗
PubMed1998

MR of the normal neonatal brain: assessment of deep structures.

BACKGROUND AND PURPOSE: MR imaging is a powerful tool for studying the anatomy of and the developmental changes that occur in the brain. The purpose of this project was to determine which structures can be distinguished on standard spin-echo MR sequences of a normal neonatal brain and with what frequency they can be identified. METHODS: The T1- and T2-weighted spin-echo MR images of 12 term neonates, all of whom had normal neonatal courses and were neurologically and developmentally normal at age 12 months, were reviewed retrospectively. All structures that differed in signal intensity from unmyelinated gray matter and unmyelinated white matter were recorded. RESULTS: In general, myelinated gray matter structures, such as cranial nerve nuclei and other nuclei of the brain stem and deep cerebrum, were the structures best seen on T2-weighted images. Most of these nuclei were seen in 75% to 100% of our subjects on T2-weighted images. They were seen less well on T1-weighted images. Myelinated white matter structures, particularly axonal tracts, were the structures best seen on T1-weighted images. The medial and lateral lemnisci, median longitudinal fasciculus, optic tracts, superior and inferior cerebellar peduncles, and the posterior limbs of the internal capsules were seen in 75% to 100% of our subjects on T1-weighted images. Except for the posterior limbs of the internal capsules, these structures were seen less well on T2-weighted images. CONCLUSION: A large number of small structures, such as the nuclei of the brain stem and deep cerebral nuclei, can be routinely identified on standard spin-echo MR imaging sequences. A knowledge of these structures is essential to proper interpretation of imaging studies in neonates and infants.

Brain↗
PubMed2005

White matter development during childhood and adolescence: a cross-sectional diffusion tensor imaging study.

Maturation of brain white matter pathways is an important factor in cognitive, behavioral, emotional and motor development during childhood and adolescence. In this study, we investigate white matter maturation as reflected by changes in anisotropy and white matter density with age. Thirty-four children and adolescents aged 6-19 years received diffusion-weighted magnetic resonance imaging scans. Among these, 30 children and adolescents also received high-resolution T1-weighed anatomical scans. A linear regression model was used to correlate fractional anisotropy (FA) values with age on a voxel-by-voxel basis. Within the regions that showed significant FA changes with age, a post hoc analysis was performed to investigate white matter density changes. With increasing age, FA values increased in prefrontal regions, in the internal capsule as well as in basal ganglia and thalamic pathways, the ventral visual pathways, and the corpus callosum. The posterior limb of the internal capsule, intrathalamic connections, and the corpus callosum showed the most significant overlaps between white matter density and FA changes with age. This study demonstrates that during childhood and adolescence, white matter anisotropy changes in brain regions that are important for attention, motor skills, cognitive ability, and memory. This typical developmental trajectory may be altered in individuals with disorders of development, cognition and behavior.

Adolescent↗
PubMed1996

Progenitor cell proliferation outside the ventricular and subventricular zones during human brain development.

The ventricular zone (VZ) and subventricular zone (SVZ) of the fetal brain are generally believed to give rise to all the neurons and glia that will populate the cerebral hemispheres. In rodents a mitotically active cell (progenitor cell) has been identified outside the VZ and SVZ, in the intermediate zone (IZ) of the cerebral hemisphere. The cell types that arise from these progenitor cells remain uncertain. We have set out to determine if a similar population of mitotically active cells is present in the IZ during human brain development, and to try and define the cell type that arise from this progenitor cell. Using a monoclonal antibody that recognizes proliferating cell nuclear antigen (PCNA), a replication-specific protein, the cerebral hemispheres from 9 human fetal and infant brains between ages of 15 and 38 weeks gestation were studied. PCNA-immunopositive cells were found in the internal capsule and cerebral white matter with approximately equal frequency and rarely in the cerebral cortex between 15 and 20 weeks gestation. In the internal capsule, the number of positive cells decreased by the end of the second trimester; however, a relatively constant number of PCNA-positive cells remained in the cerebral white matter. By the last trimester relatively little staining was found in any of the regions studied. Anti-GFAP immunostaining indicated that at least some of these progenitors were in the glial lineage. These data provide direct evidence that, in addition to ventricular zone proliferation, a population of progenitor cells continue to proliferate within nascent white matter tracts during development.

Brain↗
PubMed1987

Unilateral pseudobulbar syndrome with limited capsulothalamic infarction.

A unilateral pseudobulbar syndrome consequent to unilateral capsulothalamic infarction is described. Motor deficit of the face was associated with marked velar and pharyngeal unilateral palsy; paresis of limbs was mild. ACT scan revealed a circumscribed infarction of the genu of the internal capsule. This raised the problem of unilateral supranuclear pharyngeal palsies and of the precise anatomy of the genicular tract in the genu of the internal capsule.

Aged↗
PubMed1979

Unilateral asterixis: motor integrative dysfunction in focal vascular disease.

In three patients we found unilateral asterixis in limbs contralateral to a discrete lesion adjacent to the internal capsule. Etiology was vascular in each, with no metabolic or toxic disturbance. Unilateral asterixis bespeaks focal disease arising from lesions in the thalamus or internal capsule and is a sign of motor integrative dysfunction.

Adult↗
PubMed1993

Ataxic hemiparesis following thalamic hemorrhage: a case report.

A 66-year-old man suddenly developed right ataxic hemiparesis. Sensations, somatosensory-evoked potentials and visual-evoked potentials were normal. Magnetic resonance imaging and computed tomography of the head showed an acute hemorrhage mainly in the ventrolateral nucleus of the left thalamus. Interruption of the dentatorubrothalamocortical pathway at the level of the damaged ventrolateral nucleus of the thalamus, and the initial edema compressing the corticopontine tract in the posterior limb of the internal capsule might have contributed to the ataxia. Hemiparesis was related primarily to transient edema compressing the corticospinal tract in the posterior limb of the internal capsule.

Aged↗
PubMed1998

Development of thalamocortical projections in the South American gray short-tailed opossum (Monodelphis domestica).

We determined the time-course and general pattern of thalamocortical development of Monodelphis domestica by tracing projections with carbocyanine dye in fixed postnatal brains between postnatal day 2 (P2) and P30. By P2, the first neurons have migrated to form the preplate of the lateral cortex and have sent out axons into the intermediate zone. By P3, fibers from the preplate of more dorsal cortex have entered the intermediate zone, and, by P5, they reach the primitive internal capsule. Crystal placements in the dorsal thalamus at P2-P3 reveal thalamic axons extending down through the diencephalon and growing out through the internal capsule among groups of back-labelled cells that already project into the thalamus. Thalamic axons arrive at the cortex after the arrival of cells of the true cortical plate has split the preplate into marginal zone and subplate. Axons from the ventral part of the dorsal thalamus reach the lateral cortex by P5: Dorsal thalamic fibers arrive at the extreme dorsal cortex by P9. The deeper layers of the cortex appear to mature relatively earlier in Monodelphis than in eutherian mammals, and the subplate becomes less distinct. Thalamic fibers and their side branches proceed into the cortex without an obvious period of waiting in the subplate, but they do not penetrate the dense cortical plate itself. Monodelphis could provide an excellent model species, because the development of its thalamocortical connections is entirely an extrauterine process: The period P0-P15 corresponds to that of E12-P0 in the rat.

Animals↗