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Biomedical subjects

R Elefante

Publications and source records attributed to R Elefante.

At least 19 recordsLinked to original sources
PubMed2003

High field functional MRI.

Functional magnetic resonance imaging (fMRI) has become the most widely used approach for studying brain functions in humans. The rapid and widespread diffusion of fMRI has been favoured by the properties this technique presents, and particularly by its sensitivity in analysing brain functional phenomena and by the lack of biological invasiveness, resulting in an unprecedented and unparalleled flexibility of use. These properties of fMRI brought the functional examination of the brain within the reach of the whole neuroscience community and have appreciably stimulated the research on the functional processes of the living brain. Among the main features of fMRI, its spatial and temporal resolution represents clear advantages compared with the other methods of functional neuroimaging. In fact, the high spatial resolution of fMRI permits to produce more precise and better localised information, and its temporal resolution provides the potential of a better understanding of neural dynamics at the level of single functional areas and of the neural constituents of functional patterns. A fundamental possibility of improving spatial and temporal resolution without excessively degrading signal-to-noise ratio consists in the use of high magnetic field intensity fMRI units. Besides, high field units make the use of more demanding fMRI paradigms, like single trial event related studies, much more compatible with the need of a solid statistical evaluation. This has notably promoted the diffusion of high field MRI units for human studies throughout the world, with very high field MRI units, up to 8 T, working in a few research centres, and a larger number of MRI units with field intensity ranging between 3 and 5 T.

Brain↗
PubMed1994

Patterns of recovery and change in verbal and nonverbal functions in a case of crossed aphasia: implications for models of functional brain lateralization and localization.

We present a 2-year verbal and nonverbal follow-up of a crossed aphasic patient. The patient had suffered from widespread ischemic damage in the area of right middle cerebral artery, with a parieto-temporal lesion. Three months postonset he showed classical Wernicke's aphasia associated with oral, limb and constructional apraxia and left hemineglect. However, follow-up findings showed a complex, dynamic pattern entirely consistent with cognitive models of language and nonlanguage abilities. Current models of functional brain lateralizations could not satisfactorily account for such longitudinal, fine-grain observations.

Agraphia↗
PubMed1993

How many alien hand syndromes? Follow-up of a case.

We report the follow-up of a patient affected by a persistent alien left nondominant hand. CT and MRI showed an ischemic lesion localized to the mesial frontal region and involving the supplementary motor area and anterior fibers of the corpus callosum. These findings support theories suggesting a critical role of both these lesions in determining "chronic" forms of alien hand of either upper limb.

Brain Ischemia↗
PubMed1988

[MR vs CT: which is the diagnostic advantage in neuroradiology].

The comparative adequacy was studied of the two main neuroradiological imaging methods, MR imaging and CT, through the analysis of 1500 MR examinations with a preliminary CT study. The comparison was made by giving a score to the diagnostic contribution of MR imaging, especially as far as changes in the therapeutical approach were concerned. The results varied according to the various pathologies, to the different anatomical regions explored, and to the site of the masses. The overall score was higher in the spine and the spinal cord than in brain pathology. In brain neoplastic pathology, eg, the diagnostic capabilities of CT and MR imaging were similar in most cases, especially in supratentorial locations, while MR imaging was clearly superior in the spinal cord district. In infratentorial location, the better anatomical details make MR imaging the method of choice. In conclusion, CT confirms its accuracy in the detection of brain pathology, while MR imaging proves more sensitive in white matter diseases, and in particular locations, e.g. the posterior fossa. In the spine and spinal cord districts, the very high average score mainly confirms MR capability to demonstrate spinal canal normal and pathological content. Moreover, the important role of MR imaging is stressed in pediatric pathology, together with CT primary role in emergency cases.

Brain↗
PubMed1987

Craniopharyngioma of the cranial base and nasopharynx.

A rare case of craniopharyngioma extending to the cranial base and nasopharynx is reported and eight other cases in the literature are reviewed. The embryology and the clinical features of these tumors are discussed. Tomograms of the skull and computed tomography are the most useful radiological tools of investigation. A nasoseptal or transpalatal approach to surgery, which has been performed in reported cases of cystic nasopharyngeal craniopharyngiomas, was not performed on our patient because of the hard consistency and the diffusely infiltrating aspect of the tumor.

Adult↗
PubMed1984

[The spinal vacuum phenomenon. Radiographic and tomodensitometry aspects].

The spinal vacuum phenomenon is readily recognized by computed tomography: there fore its observation has become frequent enough. The side of the gaseous collection (intervertebral disk, vertebral body, apophyseal joint) depends on the disease inducing the phenomenon. Radiological and CT aspects of this findings are discussed. The usefulness of vacuum phenomenon in the diagnosis of several pathological conditions is examined.

Diagnosis, Differential↗
PubMed1981

[Radiological investigation of prolactin-producing pituitary microadenomas (author's transl)].

The CT scans and thin section sellar tomograms of 12 patients with amenorrhea, galactorrhea and hyperprolactinemia syndrome were analyzed. Three patients showed a remodeled sella on plain X-ray of the skull and a protrusion of the suprasellar cistern below the diaphragmatic line on pneumoencephalography (empty sella). CT scan confirmed the low absorption values within the sella and showed an intrasellar area of increased density after contrast infusion. In 9 patients, thin section tomograms showed an abnormal sellar configuration. 5 of these patients had an eccentric, high density area adjacent to the sellar floor on postcontrast CT scans. The remaining 4 patients did not show postcontrast enhancement.

Adenoma↗
PubMed1981

[Fogging effect in the ischemic cerebral infarction to computerized tomography (author's transl)].

We have examined, with systematic serial computerized tomography (CT) studies, 6 patients with persistent ischemic cerebral infarction. The CT of the ischemic cerebral infarction shows, during the third week, an isodense area. We have called this phenomenon "fogging effect" because at this effect and the CT report could be negative. The possibility of a false negative can be avoided by a control study with contrast medium: the infarction has an intensive contrast enhancement.

Adolescent↗
PubMed1977

[Radiological diagnosis of tumours of brain stem (author's transl)].

Cerebral pneumography, positive ventriculography and vertebral angiography were employed in the examination of 154 of tumour of brain stem at Departments of Neuroradiology in the city of Naples between 1962 and 1974. The findings in various sites are described and discussed and several examples are presented.

Brain Neoplasms↗