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PubMed1989

The alien hand syndrome. Clinical and postmortem findings.

Two patients had automatonlike movements of their left hands and arms (alien hand syndrome) following damage to the brain. Autopsy findings in one patient demonstrated gunshot wound damage to the medial frontal white matter bilaterally, as well as the corpus callosum, right basal ganglia, internal capsule, and thalamus. The other patient had a ruptured anterior communicating aneurysm, with subsequent resection of the right frontal gyrus rectus. We postulate that this syndrome is due to the combination of a partial callosectomy and mesial frontal lesions.

Adult↗
PubMed1989

Neurologic complications in long-standing nephropathic cystinosis.

The central nervous system has been considered to be uninvolved in nephropathic cystinosis. Survival into adulthood, following renal dialysis and transplantation, has brought attention to the sequelae of long-standing cystinosis. We examined 14 patients with cystinosis, 12 of whom had undergone renal transplantation. Two patients had neurologic symptoms. One patient had progressive bradykinesia, dementia, and spasticity with computed tomographic scan evidence of cerebral atrophy and multifocal mineralization in bilateral internal capsules and periventricular white matter. One patient had behavioral and, to a lesser extent, cognitive disturbance and computed tomographic scan evidence of marked, progressive cerebral atrophy. Although the remaining patients had normal results of neurologic examinations, 11 had roentgenographic evidence of generalized cerebral atrophy; 2 of these had abnormal electroencephalograms, 1 had borderline-deficient intellectual function, and 2 had computed tomographic scan evidence of multifocal, intracerebral mineralization. The patients with nervous system abnormalities were not distinguished by patterns of medication use, demographic or laboratory features, or the relative severity of cystinosis. Although the neurologic involvement in these patients suggests that cystinosis may eventually involve the central nervous system, the differential diagnosis must include other complications from renal failure, dialysis, and immunosuppression.

Adolescent↗
PubMed1990

Caudate infarcts.

Eighteen patients had caudate nucleus infarcts (10 left-sided; 8 right-sided). Infarcts extended into the anterior limb of the internal capsule in 9 patients, and also the anterior putamen in 5 patients. Thirteen patients had motor signs, most often a slight transient hemiparesis. Dysarthria was common (11 patients). Cognitive and behavioral abnormalities were frequent, and included abulia (10 patients), agitation and hyperactivity (7 patients), contralateral neglect (3 patients, all right caudate), and language abnormalities (2 patients, both left caudate). The majority of patients had risk factors for penetrating artery disease. Branch occlusion of Heubner's artery, or perforators from the proximal anterior or middle cerebral arteries were the posited mechanism of infarction.

Adult↗
PubMed1991

Horner's syndrome from hypothalamic infarction.

We report a case of Horner's syndrome due to ipsilateral posterior hypothalamic infarction, occurring in the absence of other signs of hypothalamic dysfunction. Associated symptoms of contralateral faciobrachial weakness and dysarthria correlated with the extension of the infarct into the posterior limb of the internal capsule seen by magnetic resonance imaging. The likely vascular anatomy of this lesion is discussed.

Cerebral Infarction↗
PubMed1991

Acute pseudobulbar or suprabulbar palsy.

We studied 13 patients with supranuclear lower cranial nerve ("pseudobulbar" or "suprabulbar") palsy of acute onset. While seven patients had had a prior stroke, six patients had no history of stroke. Eight patients experienced a complete bilateral supranuclear lower cranial nerve palsy, which was isolated in five patients and associated with hemiplegia and with hemiparesis in three patients. Pseudobulbar palsy was partial in five patients. Only one patient had neuropsychologic impairment. The pseudobulbar features improved or recovered within a few weeks in all patients. The common characteristic of the lesions on computed tomography or magnetic resonance imaging was the interruption of the corticonuclear pathways contrasting with marked sparing of the corticospinal pathways in both hemispheres. These lesions were either an opercular infarct, or a deep infarct in the corona radiata or internal capsule, or a lenticular hemorrhage. Hypertension was the most prevalent concomitant. Our findings suggest that acute pseudobulbar or suprabulbar palsy has rather stereotyped anatomic-vascular correlates and time course.

Acute Disease↗
PubMed1992

Local cerebral blood flow and its response to intravenous levodopa in progressive supranuclear palsy. Comparison with Parkinson's disease.

The local cerebral blood flow (LCBF) at steady state and after the intravenous administration of levodopa (1 mg/kg) was measured by the xenon-enhanced computed tomographic method in six patients with progressive supranuclear palsy (PSP) and in nine patients with idiopathic Parkinson's disease. The baseline LCBF values in most brain regions in patients with PSP were lower than those in patients with Parkinson's disease, and hyperfrontality of the LCBF was lost. In patients with Parkinson's disease, the injection of levodopa markedly increased LCBF, especially in the striatum, thalamus, and internal capsule (approximately 40%). In patients with PSP, however, levodopa did not increase the LCBF in all brain regions examined. The LCBF increases after the administration of levodopa in patients with Parkinson's disease may be secondary to metabolic activation of the dopaminergic system. The different LCBF responses to levodopa between patients with PSP and those with Parkinson's disease may reflect differences in pathologic features, such as in the degree of preservation of nigrostriatal dopaminergic neurons and the distribution and density of dopamine receptors, and are also related to the clinical effectiveness of levodopa therapy.

Aged↗
PubMed1995

White matter lesions and disequilibrium in older people. II. Clinicopathologic correlation.

OBJECTIVE: To identify the cause of subcortical white matter lesions seen on magnetic resonance imaging in older patients with progressive deterioration of gait and balance. DESIGN: Postmortem examination of three patients with objective impairment of gait and balance thought to be due to subcortical white matter lesions identified on magnetic resonance imaging. Brain sections were stained with routine methods and for glial fibrillary acid protein using an immunoperoxidase technique. PATIENTS: Part of a prospective study of gait and balance problems in older people. None had a history of hypertension or discrete strokelike episodes. RESULTS: Other than a few small infarcts in the basal ganglia and internal capsule in the patient with the mildest gait disorder, there were no gross or microscopic features on routine examination post mortem to explain the white matter hyperintensities on magnetic resonance imaging or the progressive gait deterioration. By contrast, immunohistochemical staining with anti-glial fibrillary acid protein showed prominent astrocytosis T2-weighted high-intensity signal areas on magnetic resonance imaging. CONCLUSIONS: The astrocytes presumably swell as they take up extravasated protein at the site of a breakdown in the blood-brain barrier, and the increased water content per unit volume increases the magnetic resonance imaging proton signal. We hypothesized that the astrocytes may have been initially activated by small infarcts or subclinical ischemia, but the process then became self-perpetuating, ultimately involving most of the white matter and producing the severe gait disorder.

Aged↗
PubMed1996

Striatopallidal and thalamic dystonia. A magnetic resonance imaging anatomoclinical study.

OBJECTIVE: To determine which brain structures are involved in symptomatic unilateral dystonia caused by localized cerebral infarction. DESIGN: Three-dimensional T1-weighted magnetic resonance imaging sequence and stereotactic analysis were used to analyze the topography of the lesions. Stereotactic localization of thalamic lesions was conducted according to the atlas of Hassler with a Voxtool software (Advantage Windows Workstation, General Electric, Milwaukee, Wis) workstation system. PATIENTS: Eight patients with hemidystonia, segmental dystonia, or focal dystonia were selected from among 51 consecutive patients (between January 1988 and May 1993) with symptomatic unilateral dystonia. RESULTS: Patients had dystonic spasms (n=4) or myoclonic dystonia (n=4). Lesions associated with dystonic spasms were located in the striatopallidal complex, and those with myoclonic dystonia were in the thalamus contralateral to the dystonia. Lesions of the striatopallidal complex involved the putamen posterior to the anterior commissure in all patients and extended variably into the dorsolateral part of the caudate nucleus, the posterior limb of the internal capsule, or the lateral segment of the globus pallidus. These lesions were centered in the "sensorimotor" part of the striatopallidal complex, with a trend toward a somatotopical distribution. Lesions of the thalamus were located in the ventral intermediate and ventral caudal nuclei, while the ventral oral anterior and posterior nuclei (which receive pallidal efferents) were largely spared. CONCLUSIONS: These results suggest that striatopallidal and thalamic dystonia may have different pathophysiologic bases.

Adolescent↗
PubMed1996

Basal ganglia and thalamic infarction in children. Cause and clinical features.

BACKGROUND: We present the signs, symptoms, and radiographic features of 36 children with ischemic infarctions of the basal ganglia, internal capsule, or thalamus. PATIENTS AND METHODS: The series includes 14 males and 22 females ranging in age from newborn to 13 years. Twenty-seven patients were evaluated with computed tomography, 34 with magnetic resonance imaging, 16 with magnetic resonance angiography, and 10 with conventional cerebral angiography. Thirty patients had unilateral lesions (16 left, 14 right) and 6 had bilateral infarctions. RESULTS: The most common presenting symptom was hemiplegia (30 of 36). Other children presented with aphasia (5 of 36), seizures (5 of 36), altered consciousness (5 of 36), and hemisensory changes (5 of 36). Four of 6 patients with bilateral lesions presented with altered mental status, but the location of a unilateral infarction within the thalamus or basal ganglia did not predict the clinical presentation. CONCLUSIONS: The risk factors for basal ganglia infarction in children are diverse, but systemic hypertension does not play a major role in children. The vascular occlusion often occurred in the large arteries, with secondary occlusion of the smaller penetrating arteries. Most children with a single unilateral infarction have a good prognosis.

Adolescent↗
PubMed1998

Role of the premotor cortex in recovery from middle cerebral artery infarction.

OBJECTIVE: To study the mechanisms underlying recovery from middle cerebral artery infarction in 7 patients with an average age of 53 years who showed marked recovery of hand function after acute severe hemiparesis caused by their first-ever stroke. INTERVENTIONS: Assessment of motor functions, transcranial magnetic stimulation, somatosensory evoked potentials, magnetic resonance imaging, and positron emission tomographic measurements of regional cerebral blood flow during finger movement activity. RESULTS: The infarctions involved the cerebral convexity along the central sulcus from the Sylvian fissure up to the hand area but spared the caudate nucleus, thalamus, middle and posterior portions of the internal capsule, and the dorsal part of the precentral gyrus in each patient. After recovery (and increase in motor function score of 57%, P<.001), the motor evoked potentials in the hand and leg muscles contralateral to the infarctions were normal, whereas the somatosensory evoked potentials from the contralateral median nerve were reduced. During fractionated finger movements of the recovered hand, regional cerebral blood flow increases occurred bilaterally in the dorsolateral and medial premotor areas but not in the sensorimotor cortex of either hemisphere. CONCLUSIONS: Motor recovery after cortical infarction in the middle cerebral artery territory appears to rely on activation of premotor cortical areas of both cerebral hemispheres. Thereby, short-term output from motor cortex is likely to be initiated.

Adult↗
PubMed2002

Acquired sexual paraphilia in patients with multiple sclerosis.

BACKGROUND: Sexual dysfunction in patients with multiple sclerosis is typically characterized by diminished libido, erectile and ejaculatory dysfunction in men, and poor lubrication and anorgasmy in women. In contrast, hypersexual behavior and paraphilias are distinctly uncommon in this population of patients, but have been associated with various focal brain lesions. PATIENT AND METHODS: We describe a man with clinically definite multiple sclerosis who developed profound and abrupt disinhibition and paraphilic behavior during an exacerbation. RESULTS: Neuroimaging revealed a marked increase in the number of enhancing lesions in the right sides of the hypothalamus and mesencephalon and extending into the right sides of the red nucleus, substantia nigra, and internal capsule. The altered sexual behavior was characterized by an obsessive and insatiable desire to touch women's breasts. CONCLUSIONS: Acquired sexual paraphilic behavior is uncommon in patients with multiple sclerosis but may occur when inflammatory demyelination involves the hypothalamic and septal regions of the basal prosencephalon. Our experience with this man illustrates the great difficulty involved in treating such patients when the paraphilic behavior becomes persistent.

Adult↗
PubMed2003

Acute infarction limited to the lenticular nucleus: clinical, etiologic, and topographic features.

BACKGROUND: Chronic diseases involving the putamen and globus pallidus induce parkinsonism and other movement disorders. Sensory and motor dysfunction from deep middle cerebral artery infarction is usually due to an involvement of the internal capsule. The clinical picture associated with isolated infarction of the lenticular nucleus is less well established. OBJECTIVE: To analyze clinical features, topographic correlations, and cause of purely lenticular ischemic infarction. PATIENTS AND METHODS: We reviewed 820 consecutive patients with deep hemispheral infarct included in the Lausanne Stroke Registry between 1986 and 1998 and selected those with isolated lenticular involvement on computed tomography or magnetic resonance imaging. RESULTS: Thirteen patients had pure lenticular infarction. All had faciobrachiocrural hemisyndrome, while none showed acute or delayed parkinsonism or abnormal movement. Nine patients had a lesion restricted to the putamen. Two of them had ataxic motor hemisyndrome and 7 had sensorimotor hemisyndrome (with ataxia in 4, left hemineglect in 1, and deep pain in the arm and leg in 1). Four patients had a lesion of putamen and globus pallidus externus. Three of them had motor hemisyndrome (with nonfluent aphasia in 2 and ataxia in 1) and 1 had ataxic sensorimotor hemisyndrome. All infarcts were in the territory of the medial perforating branches of the medial cerebral artery. Presumed cause of stroke was small-artery disease in 5, artery-to-artery embolism in 4, cardioembolism in 3 and undetermined in 1. CONCLUSIONS: Acute lenticular infarction induces mainly hemiparesis but no movement disorder. Associated sensory deficits, aphasia, and hemineglect underline clinically the function of the lenticular nucleus in connection with the prefrontal, temporal, and parietal cortices.

Acute Disease↗
PubMed2004

Acute intermittent porphyria: studies of the severe homozygous dominant disease provides insights into the neurologic attacks in acute porphyrias.

BACKGROUND: Acute intermittent porphyria (AIP), due to half-normal hydroxymethylbilane synthase activity,is characterized by acute life-threatening neurologic attacks whose etiology remains unclear. To date, only 3 patients confirmed to have homozygous dominant AIP (HD-AIP) have been described (hydroxymethylbilane synthase genotypes R167Q/R167Q and R167W/R173Q). OBJECTIVE: To investigate the genetic, biochemical, clinical, and neuroradiologic features of a severely affected infant with HD-AIP. DESIGN: Clinical, imaging, and genotype/phenotype studies were performed. RESULTS: The proband, homoallelic for hydroxymethylbilane synthase mutation R167W, had approximately 1% of normal hydroxymethylbilane synthase activity, elevated porphyrins and porphyrin precursors, severe psychomotor delay, and central and peripheral neurologic manifestations. When expressed in vitro, the R167W mutant enzyme had less than 2% of normal activity but was markedly unstable, consistent with the proband's severe phenotype. Mitochondrial respiratory chain enzymes were normal. Neuroradiologic studies revealed a unique pattern of deep cerebral white matter injury, with relative preservation of the corpus callosum, anterior limb of the internal capsule, cerebral gray matter, and infratentorial structures. CONCLUSIONS: This severely affected patient with HD-AIP expanded the phenotypic spectrum of HD-AIP. His brain magnetic resonance imaging studies suggested selective cerebral oligodendrocyte postnatal involvement in HD-AIP, whereas most structures developed prenatally were intact. These findings indicate that the neurologic manifestations result from porphyrin precursor toxicity rather than heme deficiency and suggest that porphyrin precursor toxicity is primarily responsible for the acute neurologic attacks in heterozygous AIP and other porphyrias.

Acute Disease↗
PubMed1996

Genesis and fate of the perireticular thalamic nucleus during early development.

A striking feature of the internal capsule during early development is that it is full of small neurones. Later, this group of neurones, called the perireticular thalamic nucleus, appears to have reduced in size, and only a few scattered cells are seen. In an effort to understand better the developmental history of the perireticular nucleus this study examines: i) the period of cell generation in the nucleus, ii) the magnitude of cell loss in the nucleus, and iii) the subsequent fate of cells in the nucleus during development. The perireticular cells are generated very early in development, being among the first generated in the thalamus (rats: E13-14; cats: E21-30). In rats, the first perireticular cells are generated at about the same developmental stage as the first subplate cells, which are among the first generated cells of the cortex: in cats, the first perireticular cells are generated well before those in the subplate (E24-30). In rats, the number of perireticular cells during developmental peaks at P5 (approximately 30,000) and then declines sharply (approximately 98%) by P15 (approximately 750), when adult-like patterns are seen. This dramatic loss of perireticular cells is due to both cell death and a migration of cells into the adjacent globus pallidus. The majority of the perireticular cells which migrate into the globus pallidus, however, are likely to die also. The presence of pyknotic profiles (indicators of dying cells) in the rat perireticular nucleus points to cell death as a contributor to the reduction in cell number during development. In this study, a period of relatively high pyknotic profile incidence (number of pyknotic cells per 1,000 "living" cells) is recorded in the perireticular nucleus over a 5 day period, from P2 to P7 (13.5-15.5). Similar values and patterns are recorded in the reticular nucleus and globus pallidus, except that in these structures, a period of relatively high pyknotic profile incidence (15-20) occurs over a shorter period (3 days; P2-5). Previous studies have suggested that some perireticular cells migrate into and settle within the adjacent globus pallidus. This study, with the use of long-term survivals after tracer injections in rats, shows that none (or very few) of these perireticular cells which migrate into the globus pallidus survive into more mature postnatal stages. Tracer (biotinylated dextran) was injected into the sensory nuclei of the dorsal thalamus at early stages (P7) and the rats were allowed to survive for either a day thereafter (to P8) or until well after the period of cell death was complete (to P16 or P21). In the short-term survivals (to P8), there are many dextran-labelled cells seen in the globus pallidus and in the perireticular nucleus. In the long-term survivals (to P16 or P21), by contrast, there are no dextran-labelled cells apparent in the globus pallidus or in the perireticular nucleus. It is likely that these cells in the globus pallidus, as with those in the perireticular nucleus, undergo cell death during development.

Animals↗
PubMed1996

Direct catecholaminergic-cholinergic interactions in the basal forebrain. II. Substantia nigra-ventral tegmental area projections to cholinergic neurons.

Previous observations indicate that the basal forebrain receives dopaminergic input from the ventral midbrain. The present study aimed at determining the topographic organization of these projections in the rat, and whether this input directly terminates on cholinergic neurons. Injections of the anterograde tracer Phaseolus vulgaris-leucoagglutinin (PHA-L) into discrete parts of the ventral tegmental area (VTA) and the substantia nigra pars compacta (SNC) labeled axons and terminals in distinct parts of the basal forebrain, including medial and lateral septum, diagnoal band nuclei, ventral pallidum, globus pallidus, substantia innominata, globus pallidus, and internal capsule, where PHA-L-labeled terminals abutted cholinergic (choline acetyltransferase = ChAT-containing) profiles. Three-dimensional (3-D) computerized reconstruction of immunostained sections clearly revealed distinct, albeit overlapping, subpopulations of ChAT-immunoreactive neurons apposed by PHA-L-labeled input from medial VTA (mainly in vertical and horizontal diagonal band nuclei), lateral VTA and medial SNC (ventral pallidum and anterior half of substantia innominata), and lateral SNC (caudal half of the substantia innominata and globus pallidus). At the ultrastructural level, about 40% of the selected PHA-L-labeled presynaptic terminals in the ventral pallidum and substantia innominata were found to establish synaptic specializations with ChAT-containing profiles, most of which on the cell body and proximal dendritic shafts. Convergent synaptic input of unlabeled terminals that formed asymmetric synapses with the ChAT-immunoreactive profiles were often found in close proximity to the PHA-L-labeled terminals. These observations show that the cholinergic neurons in the basal forebrain are targets of presumably dopaminergic SNC/VTA neurons, and suggest a direct modulatory role of dopamine in acetylcholine release in the cerebral cortical mantle.

Animals↗
PubMed1997

Developmental expression of keratan sulfate-like immunoreactivity distinguishes thalamic nuclei and cortical domains.

Proteoglycans influence axonal outgrowth in several experimental paradigms, and their distribution during development suggests a role in axon guidance. We have used a monoclonal antibody, 5D4, that recognizes an epitope on sulfated keratans (KS), to define the distribution of keratan sulfate proteoglycans (KSPGs) in the developing thalamus and cortex of the rat. During development, 5D4 immunolabeling is present on thalamic axons as they grow through the internal capsule and subplate but is not present in the adjacent pathway for cortical efferent axons. Individual thalamic nuclei differ markedly in their expression of KSPGs; these distinctions persist throughout the period of developmentally regulated expression. Major cortical domains also differ in their expression of KSPGs, which are expressed throughout medial (cingulate and retrosplenial) cortex well before neocortex. Immunolabeling for KSPGs diminishes 2 weeks after birth; in the adult it is associated with small glia. The 5D4 epitope is present on several KSPGs (320, 220, and 160 kD) on Western blots during development but only in a broad 200-kD band in adult brain. Immunolabeling is degraded on sections and Western blots by keratanase II but not by keratanase I or chondroitinase ABC, confirming that the antibody recognizes KS. Bands identified by 5D4 on Western blots differ from those identified by antibodies to known KSPGs (aggrecan, claustrin, SV2, ABAKAN, phosphacan-KS), indicating that 5D4 is labeling KSPGs not previously described in the brain. The selective expression of KSPGs during development suggests that they may be a part of the molecular identity of thalamic nuclei and cortical domains that defines their connectivity.

Animals↗
PubMed1997

Development of commissural neurons in the wallaby (Macropus eugenii).

We have examined the development of the laminar and areal distribution of cortical commissural neurons in a marsupial mammal, the wallaby Macropus eugenii. In this species, commissural axons approach the major cerebral commissure, the anterior commissure, via either the internal capsule or the external capsule and first cross the midline at postnatal day 14 (P14). By retrogradely labelling these axons with 1,1'-dioctadecyl-3,3,3',3'-tetramethylindocarbocyanine (DiI) at P15, we show here that the cell bodies of these neurons are restricted to a region of cortex adjacent to the rhinal fissure. Most of these labelled neurons are located in the compact cell zone of the cortical plate, with only a few labelled cells found in the zone of loosely packed cells deep to this layer. Over the subsequent 66 days, commissural neurons are found progressively more dorsally, rostrally, and caudally, so that, by P80, they are present throughout the extent of the neocortex. At this age, they are mainly pyramidal in morphology and form a single band within the deeper part of layer 5 of the developing cortex. From P80 to adulthood, the distribution of commissural neurons has been assessed in the visual cortex by using retrograde transport of horseradish peroxidase. At P80, labelled neurons with immature pyramidal morphology are present throughout the occipital cortex; as in DiI material, somata are located in deep layer 5. At P165, previously shown to be the age when commissural axon numbers peak, widespread labelling is present in the occipital region, with labelled cells now found in two bands corresponding to layers 3 and 5. After this age, neurons become more restricted in distribution, so that, by adulthood, commissural neurons are no longer apparent throughout area 17 but are restricted to a localised region around the area 17/18 boundary. Within this region, labelling is still present in layers 3 and 5 but is more dense in layer 3. The gradual restriction of commissural fields seen here in the wallaby is similar to that reported in the neocortex in many eutherians. These findings also support studies in eutheria, suggesting that subplate neurons do not appear to play a major role in commissural development.

Aging↗
PubMed2000

Pre- and postsynaptic localization of RC3/neurogranin in the adult rat spinal cord: an immunohistochemical study.

RC3 (neurogranin; BICKS) is a neuron-specific calmodulin-binding protein kinase C substrate. Thus far, immunohistochemical studies on the localization of RC3 revealed its presence in all neuronal phenotypes, which were restricted to specific areas in the neostriatum, the neocortex, and the hippocampus. RC3 was mostly found in cell bodies and dendrites, with some infrequent presence in axonal profiles, i.e. in the internal capsule. Until now, RC3 expression was reported to be absent in the adult rat spinal cord. RC3 might, however, act as an intermediate of protein kinase C-mediated signaling pathways during synaptic development and plasticity. We hypothesized a role for this 78-amino-acid protein in dendritic plasticity occurring after spinal cord injury. To our surprise, an immunohistological analysis of the uninjured adult rat spinal cord revealed the presence of RC3-positive cell bodies and dendrites in specific regions in the gray matter. Interestingly, axon-containing structures, such as the dorsal and ventral corticospinal tract, were also found to be RC3-positive. This axonal labeling was confirmed by preembedding electron microscopy. In conclusion, we demonstrate here that RC3 is present in the adult rat spinal cord in pre- and postsynaptic structures.

Animals↗