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A Beltramello

Publications and source records attributed to A Beltramello.

At least 19 recordsLinked to original sources
PubMed2000

Hippocampus and entorhinal cortex in frontotemporal dementia and Alzheimer's disease: a morphometric MRI study.

BACKGROUND: Magnetic resonance imaging (MRI) of hippocampal atrophy is a sensitive but not specific method to support the clinical diagnosis of early Alzheimer's disease (AD). We recently described our findings that atrophy of the entorhinal cortex (ERC) in frontotemporal dementia (FTD) is equal to that found in AD but that hippocampal atrophy in FTD is less than that found in AD. The MRI volumes of these structures provide a topographic representation of the region of interest. We hypothesized that two different dementias with distinct histopathologic and clinical features might, in addition to quantitative patterns, display topographically different patterns of atrophy. METHODS: We adopted a morphometric approach to monitor the pattern of atrophy of the hippocampus and the ERC by computing two-dimensional profiles from MRI volumes of the structures in control subjects and patients with FTD and AD. RESULTS: Compared with control subjects, atrophy of the hippocampus in patients with AD was diffuse. In patients with FTD, atrophy of the hippocampus was localized predominantly in the anterior hippocampus, suggesting a different pattern of hippocampal atrophy in FTD compared with AD. The amount and pattern of atrophy of the entorhinal cortex was virtually equal in both demented groups. CONCLUSIONS: This study provides novel data on the nature of medial temporal lobe atrophy in FTD. Morphometric MRI may be a useful technique for characterizing different patterns of atrophy in primary degenerative dementias in vivo.

Aged↗
PubMed2000

Apolipoprotein E genotype and hippocampal asymmetry in Alzheimer's disease: a volumetric MRI study.

Asymmetry of brain structures is common to many species and is even present in utero. Some developmental, pathological, and dementing diseases are associated with alterations in normal anatomical asymmetries. Anatomical asymmetries, however, have been only superficially studied in Alzheimer's disease. Recent evidence indicates that the allele epsilon4 of the apolipoprotein E (ApoE), a well known risk factor for Alzheimer's disease, might play a part in determining some brain morphological changes both in normal carriers and in patients with Alzheimer's disease. This study evaluated the effect of the ApoE genotype on hippocampal asymmetry in patients with Alzheimer's disease carrying 0, 1, and 2 copies of the allele. Volumetric right-left differences of the hippocampi were computed in 28 right handed patients with Alzheimer's disease (14 -/-, 9 epsilon4/-, and 5 epsilon4/4) and 30 controls without detectable cognitive deficit. In controls, the right hippocampus was larger than the left, whereas in patients with Alzheimer's disease this asymmetry was progressively reduced with increasing gene dose of the epsilon4 allele, and the asymmetry was reversed in the epsilon4/4 Alzheimer's disease group. The mean right-left volume differences were: 1.2, 0.7, 0.2, and -1.0 in controls, -/-, epsilon4/-, and epsilon4/4 patients, respectively (sex adjusted p for trend=0.017). The data indicate a dose dependent effect of the ApoE epsilon4 allele on hippocampal volume asymmetry in Alzheimer's disease.

Aged↗
PubMed1999

APOE-epsilon4 is associated with less frontal and more medial temporal lobe atrophy in AD.

OBJECTIVE: To test the hypothesis that the e4 allele of APOE is associated with a region-specific pattern of brain atrophy in AD. METHODS: Volumes of the hippocampi, entorhinal cortices, and anterior temporal and frontal lobes were measured in 28 mild to moderate AD patients and 30 controls using MRI. Within the AD group, 14 patients were noncarriers (-/-), 9 were heterozygous (e4/-), and 5 were homozygous (e4/4) for the e4 allele. Dementia severity was similar across the three AD groups. RESULTS: Smaller volumes were found with increasing dose of the e4 allele in the hippocampus, entorhinal cortex, and anterior temporal lobes in AD patients. When compared with controls, the volume loss in the right and left temporal regions ranged from -15.3 to -22.7% in the -/- AD group, from -26.2 to -36.0% in the e4/- group, and from -24.0 to -48.0% in the e4/4 group (p < 0.0005). In contrast, larger volumes were found in the frontal lobes with increasing e4 gene dose. When compared with controls, volume differences of the right frontal lobe were -11.8% in the -/- AD group, -8.5 in the e4/- group, and -1.4% in the e4/4 group (p = 0.03). CONCLUSIONS: We found smaller volumes in the temporal lobe regions but larger volumes in the frontal lobes with increasing APOE-e4 gene dose in AD patients. These data suggest a region-specific biological effect of the e4 allele in the brains of AD patients.

Aged↗
PubMed1999

Hippocampal and entorhinal cortex atrophy in frontotemporal dementia and Alzheimer's disease.

OBJECTIVE: To describe atrophic changes of the hippocampus and entorhinal cortex in frontotemporal dementia (FTD) and compare them with those of AD. BACKGROUND: The medial temporal lobe shows atrophic changes early in the course of AD, but whether these changes are specific to AD or occur in other degenerative dementias, and to what extent, is unclear. METHODS: The authors measured the volumes of the left and right hippocampus and entorhinal cortex from MR images (1.5 T, 2-mm-thick slices) in 12 patients with FTD, 30 with AD, and 30 elderly control subjects. RESULTS: In FTD patients, the left and right hippocampus (16% and 21% tissue loss) and the entorhinal cortex (28% and 27% loss) were more atrophic than the control subjects. Atrophy of the hippocampus in FTD was less severe than in AD, but atrophy of the entorhinal cortex was equally severe. Greater hippocampal and entorhinal cortex atrophy was present in the most severe patients in both groups (as high as a 49% tissue loss). The sensitivity of the hippocampus and the entorhinal cortex to discriminate FTD patients from control subjects was low (49% and 52%, respectively; specificity set at 90%), whereas hippocampal volumes could better differentiate AD patients from control subjects (80% sensitivity). CONCLUSIONS: At variance with AD, detectable in vivo atrophy of the hippocampus might not be an early event in FTD. Differential patterns of atrophy might help in the diagnostic process of the degenerative dementias.

Age Factors↗
PubMed1999

Does the tuberous sclerosis complex include intracranial aneurysms? A case report with a review of the literature.

BACKGROUND: Tuberous sclerosis is a protean, genetically determined disease that may involve any organ or tissue and lead to a great number of symptoms and clinical features. OBJECTIVE: Diagnosis can be very difficult in cases with incomplete manifestations (formes fruste) lacking the classic signs of the disease. MATERIALS AND METHODS: We report a case fulfilling the diagnostic criteria for tuberous sclerosis (shagreen patches, hypomelanotic macules, renal cysts and angiomyolipomas, and "migration tracts" in the cerebral white matter) in association with a giant intracranial aneurysm, but lacking mental retardation, epilepsy and facial angiofibroma. RESULTS: Fourteen other cases of tuberous sclerosis and intracranial aneurysms, all but one without any clear sign of polycystic kidney disease, were found in the literature. CONCLUSION: We suggest that vascular dysplasias in general and aneurysms (mainly intracranial) in particular can be added to the other non-primary diagnostic features for the clinical diagnosis of tuberous sclerosis.

Abnormalities, Multiple↗
PubMed1999

Superficial siderosis of the central nervous system and anticoagulant therapy: a case report.

Superficial siderosis of the central nervous system is a rare condition characterized by deposition of haemosiderin in the leptomeninges and in the subpial layers of the brain and spinal cord. With the widespread use of magnetic resonance imaging, an increasing number of cases of superficial siderosis are being discovered, secondary forms being more frequent than idiopathic ones. We report a 78-year-old man in oral anticoagulant therapy, who presented neurosensory hearing loss, gait ataxia and spastic paraparesis. Magnetic resonance imaging suggested the diagnosis of superficial siderosis of the central nervous system, without an evident bleeding source.

Aged↗
PubMed1998

Motor representation of the hand in the human cortex: an f-MRI study with a conventional 1.5 T clinical unit.

The purpose of this study was to show a gradient of possible bilateral activation for movements of the non-dominant vs. dominant hand, as well as for areas involved in complex vs. simple hand movements. A standard 1.5 T magnetic resonance imaging (MRI) system has been utilized to localize the cortical motor hand areas, using the blood oxygen level dependent contrast (BOLDc) technique and single-section fast low-angle shot (FLASH) imaging. Ten normal right-handed subjects volunteered for the study. The motor tasks consisted of simple (flexion-extension) finger movements of either hand, and complex movements (finger-to-thumb opposition in a repeating, pre-planned sequence) of the non-dominant hand. Simple movements caused contralateral activation of the primary motor area (MA); ipsilateral activation was observed for the non-dominant hand only. Supplementary motor area (SMA) was also activated, with a clear contralateral prevalence. The ratio of bilateral activation of MA did not change with complex movements of the non-dominant hand, while SMA as well as lateral premotor area were largely bilaterally activated in this task. In conclusion, the ipsilateral MA is activated for movements--even simple--performed with the non-dominant hand. There is widespread functional activity, involving both contralateral and ipsilateral SMA, for complex movements.

Adult↗
PubMed1998

Neuropsychological and neuroimaging correlates in corticobasal degeneration.

The aim of this study was to correlate neuropsychological and neuroimaging findings in corticobasal degeneration (CBD). Three patients with clinical criteria for CBD were examined by means of neuropsychological tests, brain magnetic resonance imaging (MRI), and flow and metabolism neuroimaging techniques. Neuropsychological assessment revealed impairment in executive functions, manual dexterity and motor programming with significant asymmetry between upper limbs. Ideomotor and oral apraxia were also detected, and memory deficits were observed in one patient. MRI revealed cortical dilation of the frontal and peri-rolandic regions, symmetrical in one case and asymmetrical in the other two cases. An increased T2 signal intensity in the posterolateral putamen and substantia nigra ipsilateral to the cortical atrophy was observed in one patient. Asymmetries of both frontal and parietal cortices and basal ganglia were detected in all three patients by 18-fluorodeoxyglucose positron emission tomography; temporal region hypometabolism was associated in one patient. These cortical and subcortical asymmetries were observed in two patients by single photon emission tomography with the tracer technetium Tc 99m hexamethyl propylenamine oxime; cortical asymmetry was observed in only one patient. The results showed that functional neuroimaging findings correlated well with neuropsychological aspects in CBD. Neuroimaging and neuropsychological correlations may contribute toward understanding anatomical and functional abnormalities associated with this neurodegenerative disorder.

Aged↗
PubMed1998

Spike topography and functional magnetic resonance imaging (fMRI) in benign rolandic epilepsy with spikes evoked by tapping stimulation.

We performed a spike topography study and a functional magnetic resonance imaging (fMRI) in a female patient with benign rolandic epilepsy presenting single high-amplitude evoked spikes in response to somatosensory peripheral stimulation. The stimulus was delivered to the first finger of the right hand using a tendon hammer, which evoked a single spike followed by a slow wave, showing the maximal amplitude over the left central regions. fMRI showed that the contralateral sensory cortices (S1 and S2) and the motor cortex (M I) were activated during tapping stimulation. In 3 normal subjects, tapping stimulation produced no fMRI activation. This fMRI study documents a highly focal activation of sensorimotor areas related to subclinical evoked spikes in benign rolandic epilepsy.

Acoustic Stimulation↗
PubMed1998

Paradoxically greater interhemispheric transfer deficits in partial than complete callosal agenesis.

Symptoms of interhemispheric disconnection are typically much less severe in callosal agenesis than after surgical section of the corpus callosum. Sperry [Sperry, R. W., Plasticity of neural maturation. Developmental Biology, 1968, 2 (Suppl.), 306-327.] has attributed this difference to two interconnected factors: (1) the callosal section is usually performed after the brain has lost the maximal degree of functional plasticity associated with the early stages of development and (2) the removal of an already formed structure is more disruptive for functional brain organization than the failure of the same structure to develop. It has been suggested that functional compensation is less efficient if callosal agenesis is partial rather than complete [Dennis, M., Impaired sensory and motor differentiation with corpus callosum agenesis: A lack of callosal inhibition during ontogeny? Neuropsychologia, 1976, 14, 455-469.]. This suggestion is supported by the present findings of partial left-hand anomia, partial left-field alexia and poor tactile cross-localization in a subject with a congenital absence of the posterior part of the corpus callosum due to an arteriovenous malformation. In agreement with many previous studies, similar, though more severe, symptoms of interhemispheric disconnection were found in a subject with a complete section of the corpus callosum, but not in a subject with complete callosal agenesis. Praxic control of the left hand on verbal commands was severely deficient in the callosotomy subject, but it was normal in the subject with callosal hypogenesis. The lesser degree of compensation in partial compared to complete callosal agenesis may be explained by a reduced pressure to develop extracallosal means of interhemispheric communication, contingent on the partial existence of callosal connections, as well as by the later occurrence in development of the causes of callosal hypogenesis compared to those of total callosal agenesis.

Agenesis of Corpus Callosum↗
PubMed1998

Computed tomography and magnetic resonance imaging in the management of coronoid process hyperplasia: review of five cases.

OBJECTIVE: To describe the imaging features of primary bilateral coronoid hyperplasia, with particular reference to the use of CT and MRI. MATERIALS: A series of five cases is reviewed. RESULTS: The correct diagnosis was achieved with panoramic radiography alone or with the addition of CT. MRI did not provide additional pre-operative information; it was useful in the postoperative assessment of poor functional recovery in order to determine the presence of haematoma and/or fibrosis. CONCLUSIONS: Although panoramic radiography alone can demonstrate this condition, CT has an important role in diagnosis and is useful for an adequate surgical planning by allowing assessment of the size of impingement of the coronoid processes. MRI is useful for evaluating postoperative complications involving soft tissue.

Adolescent↗
PubMed1998

Intracranial myxoid chondrosarcoma with early intradural growth.

Chondrosarcomas are extremely rare intracranial cartilaginous tumors of which the myxoid variant is the least reported in the literature. They develop extradurally and generally infiltrate the dura only in advanced stages or at recurrence. We describe the case of a 55-year-old woman with a posterior cranial fossa myxoid chondrosarcoma which had a primarily intradural extension.

Chondrosarcoma↗