Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “Neuroimaging”

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 991 records · Page 55Linked to original sources
PubMed1995

[Three cases of clinically diagnosed corticobasal degeneration--neuroimaging studies with MRI, SPECT and PET].

We report three cases of clinically diagnosed corticobasal degeneration: a 63-year-old male, a 63-year-old female and a 62-year-old female. All the three patients exhibited asymmetric limb-kinetic apraxia and extrapyramidal signs. Neuroimaging studies with MRI, 123I-IMP SPECT and FDG-PET were performed in each of the three cases and FDOPA-PET was performed in patient 1. MRI analysis showed asymmetric cortical atrophy, especially in the parietal cortex, in all the three cases. 123I-IMP SPECT analysis revealed asymmetric reduction of the cerebral blood flow, in accordance with the MRI findings. FDG-PET analysis showed marked asymmetric reduction (> or = 10%) of cerebral metabolic rates for glucose (CMRGlc) in the lateral frontal cortex, lateral posterior frontal cortex and primary motor and sensory cortex in all the patients, although the asymmetry in the thalamus which had been described as a characteristic CBD finding in previous reports was not observed in any of the patients in our study. FDOPA-PET analysis revealed reduction of uptake in both the putamen and caudate nucleus, predominantly in the caudate nucleus, which suggests that the FDOPA-PET findings correlate with the extrapyramidal signs observed in the case of the 63-year-old male.

Basal Ganglia↗
PubMed1996

[Neuroimaging techniques in the Gilles de la Tourette syndrome].

Tourette's syndrome (GdT) is a chronic neuropsychiatric disorder of unclear etiology characterized clinically by the presence of motor and phonic tics as well as a variety of behavioral and cognitive abnormalities such as Obsessive-Compulsive Disorder (TOC) and Attention Deficit Hyperactivity Disorder (ADHD). Dopaminergic pathway and movement control related structures may have some implications for pathogenesis. Neuroimaging techniques may yield relevant data for a better understanding of the symptoms and physiopathology of this disease. Among them, functional isotopic techniques such as PET and SPECT and other like quantitative EEG are the most remarkable. In this article we intend to perform a thorough review of the most recent literature, contributing with our own experience and discuss the pathogenesis of GdT.

Attention Deficit Disorder with Hyperactivity↗
PubMed1996

Diagnostic neuroimaging: computed tomography and magnetic resonance imaging.

BACKGROUND: Computed tomography (CT) and magnetic resonance imaging (MR) are commonly used neuroimaging modalities for patients with signs or symptoms of neuro-ophthalmic disorders. Understanding the technology and clinical uses of these modalities is vital in patient management. METHODS/RESULTS: Basic instrument design and technology are presented together with a discussion of indications and contraindications to the use of these imaging techniques. Case reports are presented to illustrate the usefulness in diagnosis of orbital and neuro-ophthalmic disease. CONCLUSIONS: A basic knowledge of CT and MR helps the optometrist correlate imaging with clinical signs and symptoms of disease. This understanding also results in more effective communication with other health care providers and patients.

Adult↗
PubMed1996

[Leigh's encephalopathy (subacute necrotizing encephalopathy). Documentation of its evolution through neuroimaging].

A 30 months-old boy developed bilateral nistagmus, tremor, gait disturbance, hypotonia and disartria. The diagnose of Leigh encephalopathy was suggested on the basis of clinical, neuroimaging and laboratory findings. Computed tomography and magnetic resonance imaging (MRI) at an early stage revealed bilateral and symmetric lesions in the putamen, appearing as hyperintense signal on T2-weighted images. Twelve months later a relatively large hypertense area in the posterior brainstem was observed. At this stage, the patient exhibited marked deterioration, dystonic manifestations, rigidity and respiratory disturbances. He died 6 months later for respiratory arrest during bronconeumonic infection. We believe MRI is a valuable means to allow assessment of the evolution of the disease.

Child, Preschool↗
PubMed1996

[Neuroimaging and epilepsy].

The objective of magnetic resonance neuroimaging is to define the structural changes responsible for epileptogenic lesions and to rule out the presence of dual pathology when partial epileptic seizures are being studied. To this end, the individualization and optimization of protocols and sequences is indispensable. Structural images must be complemented by clinical evidence and function studies (EEG, SPECT, PET) in order to determine whether the structural lesion is responsible for the seizure and might eventually be excised. Spectroscopy provides biochemical information that is somewhat comparable to that obtained by biopsy of the epileptogenic zone. Spectroscopic images in the near future will provide clear "blind" views of these zones. Functional magnetic resonance images will presumably be of great help in the management of these patients.

Arteriovenous Malformations↗
PubMed1996

[Neuroimaging and efficacy of treatment in advanced African trypanosomiasis].

INTRODUCTION: West African trypanosomiasis (WAT) is rare in Spain. Delay in its diagnosis and treatment leads to irreversible diffuse meningoencephalitis and finally death of the patients. CLINICAL CASE: We described a patient in whom the diagnosis of advance WAT had been delayed. He had headache, alteration of the level of consciousness and sleep pattern, psychiatric disorders, crises, extrapyramidal, sensitive and endocrinological clinical alterations. Biochemical investigation showed slight anemia with marked thrombocytopenia, and raised ESR and IgM. Initially serology was negative for trypanosomes, although examination of the CSF confirmed the diagnosis. MR showed extensive lesions of the basal nuclei, brainstem and white matter. Both the clinical abnormalities and the lesions shown on MR disappeared after treatment with intravenous difluoromethylornithine. The patient is now symptom-free and at work as usual. DISCUSSION: Find diagnosis of WAT requires isolation of the parasite from the blood, the bone marrow or CSF. When other complementary tests (such as serology) are negative, the diagnosis should not be ruled out. There are few neuroimaging studies of WAT, and only by CT. We have found no MR studies of patients with WAT, in the literature. We emphasize the close correlation between the clinical and radiological findings in this case, and the excellent result obtained after treatment.

Adult↗
PubMed1997

[Neuroimagings in neuronal migration disorders].

Recent progress in magnetic resonance imaging (MRI) has successfully visualized neuronal migration disorders (NMDs) without autopsy. NMDs are observed in the patients with hydranencephaly, porencephaly, cerebellar hypoplasia, agenesis of corpus callosum, agenesis of septum pellucidum and holoprocencephaly. Miller-Dieker syndrome, Fukuyama-type congenital muscular dystrophy, Walker-Warburg syndrome, hypomelanosis of Ito, congenital rubella syndrome, toxoplasmosis, Zellweger syndrome and other diseases are also associated with lissencephaly, pachygyria and polymicrogyria. Neuroimagings of illustrative cases with NMDs were shown here.

Adolescent↗
PubMed1997

Neuroimaging of central nervous system tuberculosis in HIV-infected patients.

The recent resurgence of tuberculosis in the United States is in part attributable to the AIDS epidemic. Central nervous system tuberculosis has fairly specific radiographic features, and thus the alert radiologist may be the first to suggest this diagnosis. This article reviews the neuroimaging characteristics of central nervous system tuberculosis in HIV-seropositive patients, including intracranial manifestations, tuberculous spondylitis, and tuberculous arachnoiditis.

AIDS-Related Opportunistic Infections↗
PubMed1997

The noninvasive identification of language function. Neuroimaging and rapid transcranial magnetic stimulation.

Neuroimaging techniques that rely on detecting alterations in blood flow may be used to map the cortical localization of cognitive function during task performance. O-15 water positron emission tomography studies have mapped neural networks that subserve language function. These techniques have been adapted to lateralize and localize language function in patients with intractable epilepsy prior to epilepsy surgery. Functional magnetic resonance (fMR) imaging, relying upon fast MR imaging techniques performed during cognitive tasks, allows localization of language areas in individual adults and children and, because there is no radiation exposure, allows for additional or repeat studies in patients. These noninvasive means of language localization may supplant the invasive means of language lateralization (intracarotid amytal procedure) and localization (corticography), and will allow for the continued study of language organization in health and disease.

Brain↗
PubMed1997

[Dolichoectasia of multiple cranial arteries. Findings on neuroimaging and transcranial Doppler].

INTRODUCTION: Dolichoectasia of the intracranial arteries may give rise to ischaemic or haemorragic pathology and to compression phenomena. Joint dolichoectasia of the whole circle of Willis, in both the anterior and basilar portions extending to the main basal arteries is an unusual finding. CLINICAL CASE: We describe a 76 year old man who presented with vertigo with vertically downward nystagmus. On neuroimaging studies there was aneurysmal dilation of the left vertebral, basilar and both carotid arteries (in their supra-clinoid portion) and of both medial cerebral arteries. Transcraneal Doppler showed marked reduction in flow rate with normal morphology and pulsation. CONCLUSION: The combination of non-invasive techniques allows full, reliable evaluation of the swollen arteries and possible complications.

Aged↗
PubMed1997

Hypoxic-ischemic brain injury in the term newborn. Neuropathology, clinical aspects, and neuroimaging.

Hypoxic-ischemic cerebral injury in the full-term infant results in a variety of neurologic manifestations. The pathogenetic events resulting in this central nervous system injury may occur throughout the prenatal period. Several clinical patterns of signs and symptoms of hypoxic-ischemic cerebral injury have been identified in the term infant. Further, characteristic neuroradiologic patterns of this injury can be discerned. Information derived from the term infant's clinical course and neuroimaging data convey useful neurodevelopmental prognostic information. Several potential and promising therapeutic agents exist may attenuate the sequelae of hypoxic-ischemic cerebral injury to the term infant.

Asphyxia Neonatorum↗
PubMedDate not supplied

[Lacunar strokes: clinical conditions vs. localization of lesions in neuroimaging studies].

Clinical records of 89 patients with lacunar stroke were reviewed, to evaluate the occurrence of neurological syndrome and to correlate the frequency of its signs with the localization of ischaemic lesions seen in neuroimaging examinations. "Pure" motor paresis (50%) and sensory-motor paresis (27%) were the most common clinical syndromes. The localization in putamen and corona radiata (37%), or in anterior part of the internal capsule and in the head of the caudate nucleus (35%) were the most frequent sites of localization. In the group of patients with lesions in anterior part of internal capsule or with lesions in putamen and corona radiata "pure" motor paresis was the most common clinical syndrome. Additionally, in the group of patients with lesions in putamen and corona radiata sensory motor paresis was also frequently observed (44%). During one year of follow-up 22 patients died. Dysarthria and disability (Barthel Index < 60) were the independent predictors of one year mortality. Non-neurological complications were the main cause of death.

Aged↗
PubMed1998

Magnetization transfer in neuroimaging.

Magnetization transfer (MT) imaging has become a focus of recent basic science and clinical investigations because of its unique physical basis of contrast, and the potential to quantify aspects of the biochemical structure and composition of tissues. In this article, basic theories of MT are discussed, and several practical MT pulse and sequence considerations are addressed. The clinical utility of MT techniques in MR angiography, postgadolinium T1-weighted scanning, and spine scanning are discussed. Highlights of quantitative MT studies for pathologic tissue characterization and for studies of patients with white-matter disorders such as multiple sclerosis are included, giving a comprehensive review of the neuroimaging application of MT.

Brain↗
PubMed1998

Rasmussen encephalitis: complementary role of multitechnique neuroimaging.

Rasmussen encephalitis is a chronic, progressive inflammation of the brain of unknown origin. Early diagnosis and treatment with immunoactive agents and/or hemispherectomy are sought to prevent the progressive cognitive decline that accompanies this disease. Combined anatomic and functional neuroimaging may serve to focus the diagnostic workup and to hasten brain biopsy for definitive diagnosis. Two biopsy proved cases of Rasmussen encephalitis are presented. The importance of MR imaging, single-photon emission computed tomography, and proton MR spectroscopy in the workup of this disease is discussed.

Child↗
PubMed1998

Neural response during preference and memory judgments for subliminally presented stimuli: a functional neuroimaging study.

Preexposing subjects to visual stimuli is sufficient to establish a subsequent preference, even when previous exposure is subliminal, such that explicit recognition is at chance. This influence of previous exposure on preference judgments, known as the "mere exposure effect," is a form of unconscious memory. The present functional neuroimaging study examines the mechanism of this effect. Nine volunteer subjects were studied using functional imaging while making forced choice judgments about abstract stimuli on the basis of either preference or memory. Each judgment type was made under two conditions: under one condition one or the other stimulus had previously been presented subliminally, whereas under the second condition both stimuli were novel. Memory judgments were associated with activation of left frontopolar cortex and parietal areas, whereas preference judgments were associated with activation of medial prefrontal cortex and regions of occipital cortex. The modulation of preference by objective familiarity (implicit memory) was associated with right lateral frontal activation. Significant activation of hippocampal gyrus was seen in response to objective stimulus novelty, regardless of judgment type required. Our data thus demonstrate activations of a memory system independent of recollective experience. Dissociable activations within this system implicate a frontopolar involvement in explicit retrieval attempt and right lateral prefrontal cortex involvement in implicit memory expressed in preference judgments. Furthermore, the results suggest that hippocampal response to stimulus novelty can be independent of conscious reportability of familiarity.

Adult↗
PubMed1998

[Lhermitte-Duclos disease in a ten-year-old child: clinical follow-up and neuroimaging data from birth].

INTRODUCTION: Lhermitte-Duclos disease is a rare lesion characterized by enlarged cerebellar folia containing abnormal ganglion cells. It typically affects young adults, and reports in the pediatric age are exceptional. CLINICAL CASE: This case report describes a child with slowly progressive macrocephaly, which was already present at birth, delayed motor development, and clumsiness. At 7 years of age a mild ataxia appeared, which remained stationary until 10 years of age when he developed signs of intracranial pressure (headache and papilloedema). A CT scan at 2 years of age showed an enlarged posterior fossa with asymmetrical cerebellum; another study at 7 years of age disclosed mild ventricular dilatation. IRM at 10 years of age showed aqueductal obliteration by an enlarged cerebellum. The cerebellar lesion consisted of abnormally thickened folia with abnormal hyperintensity of the central cerebellum on the T2-weighted images. The lesion did not enhance with gadolinium. The histological findings were typical of Lhermitte-Duclos disease. CONCLUSIONS: In our patient the lesion behaved like a slowly growing mass, but both neuroimaging and pathological studies were suggestive of a hamartomatous rather than a true neoplastic disorder. Furthermore, there was clinical evidence that the disorder was already present at birth. All the evidences in our case support the concept that this growing lesion represents a congenital abnormality.

Ataxia↗
PubMedDate not supplied

[Biological markers of schizophrenic symptoms: functional neuroimaging].

Despite heterogeneous phenotype, lack of pathognomonic symptoms and great variability of symptoms during the course of the illness, functional neuroimaging studies have showed specific patterns of activation associated to particular schizophrenic symptoms or symptom dimensions. Negative symptoms have been associated to hypofrontality; auditory hallucinations seem to be related to abnormalities in brain regions involved in language and, reality distortion dimension has been associated to left temporal lobe impairments.

Biomarkers↗
PubMed1998

[Memory in multiple sclerosis: review of performance and relationship with clinical variables and neuroimaging].

INTRODUCTION: Neuropsychological studies in multiple sclerosis (MS) mainly have centred on the study of memory disorder. DEVELOPMENT: The prevalence of memory deficits in MS population is around 40-60%. These deficits could be sum up in an impaired immediate memory, a learning capacity lower than normal controls subjects and a worse long term memory. The results of the reviewed studies about the relationship between performance in memory tasks and clinical variables, show that physical disability and depressive symptoms do not influence this performance. Whilst, years of evolution and, mainly, disease course are related to a worse performance in memory tasks. In structural neuroimaging studies (CT and MRI) it is considered that ventricular dilatation and the total lesion load are predictor variables of MS patients performance in different memory tasks. CONCLUSION: This paper reviews several studies relative to amnesic function in subjects suffering from MS, emphasizing the most relevant contributions of the present neuropsychological literature.

Brain↗