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At least 1,081 records · Page 60Linked to original sources
PubMed1995

Randomised double-blind clinical trial of intermediate- versus high-dose chloral hydrate for neuroimaging of children.

Orally administered chloral hydrate is the most widely used sedative in children undergoing MRI. We compared intermediate- and high-dose oral chloral hydrate in 97 consecutive children undergoing MRI in a prospective, controlled, double-blind, randomised clinical trial. There were 50 girls and 47 boys, mean weight (+/- SD) 14.7 +/- 6.4 kg, and mean age 38 +/- 31. The children were randomly allocated to receive chloral hydrate syrup either 70 mg/kg (group A, n = 50) or 100 mg/kg (group B, n = 47). These two groups were not significantly different in sex, weight, age, diagnosis or ambulatory medication. The mean initial dose (+/- SEM) was 64 +/- 2 mg/kg for group A and 93 +/- 2 mg/kg for group B. Because adequate sedation was not achieved, 14 patients in group A and 6 in group B required a second dose, giving a mean total dose of 70 +/- 2 mg/kg for group A and 96 +/- 2 mg/kg for group B. The percentage of successful examinations after the initial dose (A: 64%, B: 87%; p < 0.05) and the total dose (A: 92%, B:100%; p = 0.14) was higher in group B. Significant differences were found for the time of onset of sedation (A:28 +/- 2 min, B: 21 +/- 1 min; p < 0.05), but not for the time to spontaneous awakening after the completion of the examination. The rate of adverse reactions was similar (A: 20%, B: 21%; p = 1.00). We conclude that high-dose oral chloral hydrate improves the management of children undergoing MRI.

Adolescent↗
PubMed1992

MRI and SPECT findings in amyotrophic lateral sclerosis. Demonstration of upper motor neurone involvement by clinical neuroimaging.

MRI was performed in 21 patients and single photon emission computed tomography (SPECT) with N-isopropyl-p-123I iodoamphetamine in 16 patients, to visualize upper motor neurone lesions in amyotrophic lateral sclerosis. T2-weighted MRI revealed high signal along the course of the pyramidal tract in the internal capsule and cerebral peduncle in 4 of 21 patients. SPECT images were normal in 4 patients, but uptake was reduced in the cerebral cortex that includes the motor area in 11.

Adult↗
PubMed1992

Tay-Sachs disease: progression of changes on neuroimaging in four cases.

The neuroradiological findings in four patients with Tay-Sachs disease are described in three phases of the clinical course. The basal ganglia and cerebral white matter show low density on computed tomography and high signal intensity on T2-weighted magnetic resonance imaging in the initial phase. The caudate nuclei are characteristically enlarged and protrude into the lateral ventricles in the first and second phases. The cerebral white matter shows low density on the CT which varies in extent from the second to third phases, and the whole brain becomes atrophic in the last phase. Thus, central nervous system involvement in the disease may begin in basal ganglia as well as in cerebral white matter.

Atrophy↗
PubMed1995

Neuroimaging in alcoholism: CT and MRI results and clinical correlates.

For more than a century we have known the deleterious effects of alcohol on the brain regions surrounding the third ventricle and on the cerebellum. But it was only recently that we gained clearer evidence that the cortex is affected as well. Our imaging studies show that brain shrinkage is at least partially reversible once abstinence is maintained. They confirm results obtained in different laboratories from all over the world. Although our data contradict the rehydration hypothesis and thus lend credence to the idea of regeneration and neuroplasticity, the nature of reversibility is still a matter of debate.

Alcoholism↗
PubMed1996

Evolution of the neuroimaging changes in fucosidosis type II.

We report on clinical and neuroradiological findings in two patients with fucosidosis type II; a 7-year-old Jordanian boy and a 3 1/2-year-old Anglo-Canadian girl. This rare, autosomal recessive disorder is caused by deficiency of lysosomal alpha-fucosidase and is manifested clinically by progressive mental and motor deterioration, coarse facies, growth retardation, recurrent infections, dysostosis multiplex, angiokeratoma corporis diffusum, visceromegaly and seizures. Cranial CT and magnetic resonance imaging showed density and signal abnormalities in the thalamus, globus pallidus and internal capsules bilaterally, as well as progressive CT density alterations in supratentorial white matter including the internal medullary laminae of the thalami and the internal capsules.

Brain↗
PubMed1996

Familial cavernous hemangioma with atypical neuroimaging.

Three members of the same family were studied, all of whom had multiple intracerebral cavernous angiomas for which a dominant autosomal inheritance was hypothesised. The proband suffered from headaches, and physical examination revealed evident right hemiparesis. The second case started with a hemorrhagic cerebral stroke and the third was asymptomatic on neurological examination. Nuclear magnetic resonance (NMR), performed in two of the three cases, showed lesions whose number and extent were not radiologically characteristic of cavernous angioma. A cerebral biopsy of the proband enabled the diagnosis to be made. Despite the recent introduction of NMR, the nosological classification of familial forms can be difficult when the radiological lesions are atypical. In such cases, cerebral biopsy is not only a valid diagnostic aid, but is also indispensable for obtaining adequate genetic information.

Brain↗
PubMed1992

Neuroimaging in tuberous sclerosis: a clinicoradiological evaluation in pediatric patients.

CT, MRI and neurological features of 27 children with tuberous sclerosis were prospectively compared. Imaging studies were positive in 92.5% of cases. CT was more useful in detecting subependymal nodules, while MRI showed the number and location of cerebral cortical and subcortical lesions more accurately. Cortical lesions in the cerebellar hemispheres were present in 26% of patients. Gadolinium-DTPA used in 10 patients showed slight enhancement of the subependymal lesions in 80% of cases, probably representing active lesions with alteration of the blood-brain barrier. None of the cortical and subcortical lesions enhanced. Giant-cell astrocytomas were detected in 5 patients, the postcontrast CT and MRI studies improving their assessment. Unlike subependymal nodules, all tumors showed marked enhancement regardless of their size. Seizures were present in 96% of patients, mostly beginning before 1 year of age. There was no clear relationship between the radiological features and the neurological evolution of these patients. Therefore, it is not possible to establish a clinical prognosis based on the radiological findings. MRI is the procedure of choice in the diagnosis of tuberous sclerosis. When pre and postcontrast MRI are negative, CT is used to exclude small calcified subependymal nodules. MRI follow-up is required only when tumoral development is clinically suspected.

Adolescent↗
PubMed1995

Central precocious puberty: evaluation by neuroimaging.

To evaluate the incidence of abnormal intracranial findings in children with central precocious puberty, 62 children (51 girls, 11 boys) were examined by computerized tomography and/or magnetic resonance imaging (MRI) of the brain. Forty-four had normal examinations; 18 (11 girls, 7 boys) showed intracranial pathologies, including hamartoma of the tuber cinereum (8 cases), parenchymal loss (3 cases), hypothalamic-chiasmatic lesions (2 cases), lesions of the corpus callosum (2 cases), suprasellar cyst (1 case), and pineal cyst and mesiotemporal sclerosis (1 case each). Based on the correlation between the clinical and the imaging results of this series, the authors recommend MRI as the imaging method of choice in the investigation of precocious puberty.

Brain Diseases↗
PubMed1991

Association of "top of the basilar" syndrome with megadolichobasilar artery. Clinical and neuroimaging evaluation.

We describe the case of a patient with a history of trigeminal neuralgia who suddenly developed the "top of the basilar" syndrome. MRI disclosed ischemic lesions in the left paramedian mesencephalic tectum, in the left ventral thalamus, in the left occipital lobe and a megadolichobasilar artery (MDBA). The association of MDBA with the top of the basilar syndrome is rarely reported. We discuss the possible hemodynamic mechanism producing a top of the basilar syndrome in the presence of MDBA.

Aged↗
PubMed1996

Stimulating technetium-99m cerebral perfusion studies with a three-dimensional Hoffmann brain phantom: collimator and filter selection in SPECT neuroimaging.

The choice of collimator and the selection of a filter can affect the quality of clinical SPECT images of the brain. The compromises that 4 different collimators make between spatial resolution and sensitivity were studied by imaging a three-dimensional Hoffmann brain phantom. The planar data were acquired with each collimator on a three-headed SPECT system and were reconstructed with both a standard Butterworth filter and a Wiener pre-filter. The reconstructed images were then evaluated by specialists in nuclear medicine and were also quantitatively analyzed with specific regions of interest (ROI) in the brain. All observers preferred the Wiener filter reconstructed images regardless of the collimator used to acquire the planar images. With this filter, the ultrahigh-resolution fan-beam collimator was the most subjectively preferable and quantitatively produced the highest contrast ratios. The findings support suggestions that higher resolution collimators are preferable to higher sensitivity collimators, and indicate that fan-beam collimators are preferable to parallel-hole collimators for clinical SPECT studies of cerebral perfusion. The results also suggest that Wiener filter enhances the quality of SPECT brain images regardless of which collimator is used to acquire the data.

Brain↗
PubMed2001

Structural neuroimaging of Alzheimer's disease and other dementias.

This paper reviews the use of imaging techniques to aid in the clinical diagnosis of dementia. Two approaches are distinguished. One is the exclusionary approach in which imaging is used to rule out diseases that would mimic or cause dementia; based on the literature, this approach yields very little, if any, information that was not identified clinically. The more positive approach uses imaging as a diagnostic tool to identify changes specific for causes of dementia; any assessment of medial temporal lobe atrophy on Magnetic Resonance Imaging (MRI) will result in a reasonably high positive likelihood ratio distinguishing AD patients from non-demented individuals, but fails to distinguish AD patients from patients with other dementias. For a diagnosis of vascular dementia imaging is necessary, although not all vascular changes fulfill requirements of being relevant to dementia. Potentially of more importance, given the higher prevalence of AD, is the identification of concomitant vascular changes in AD that may be amenable to therapy, and may be used to identify subgroups. Structural and functional MRI techniques have great potential in identifying patients at risk for AD, which will allow for a very early treatment with drugs that slow or even halt progression.

Aged↗
PubMed1997

Functional neuroimaging in the assessment of CNS neoplasms.

Assessment of CNS neoplasms has focused traditionally on morphological analysis. Recent developments in MR sequence design now enable functional assessments. T1-weighted, as well as T2(*)-weighted, dynamic, gadolinium-enhanced, imaging can be used for assessment of vascularisation, permeability, and microcirculation of CNS neoplasms. Characterisation of cerebrovascular blood flow is possible using dynamic MR angiography, while neurofunctional imaging enables visualisation of local alterations in neuronal activity in stimulated cortical areas. Diffusion-weighted imaging can be used for improved delineation of neoplasms, while chemical shift imaging allows metabolic mapping of lesions and surrounding tissues. Implementation of these techniques can improve characterisation, information for therapy, planning and prognosis in clinical imaging of CNS neoplasms.

Brain↗
PubMed1999

Structural neuroimaging in schizophrenia. An integrative view of neuromorphology.

The use of structural magnetic resonance imaging (MRI) in studies of schizophrenia has resulted in a more detailed picture of anatomic areas which may be altered in this syndrome. Thus far, there have been over 130 studies of schizophrenia using MRI and, taken together, they present a clear picture of a group of disorders with altered brain structure. Their major finding is a confirmation of the older pneumoencephalography and computertomography studies showing an enlargement of lateral ventricles and a volume reduction seen in the temporal lobe. When structural studies are carried out in other cortical and subcortical regions, however, the volume reduction is not so uniform, but rather restricted to certain areas in a given patient. In addition medication effects can be seen especially in the caudate nucleus which tend to increase in volume after long-term neuroleptic drug usage and again normalize under the atypical drug clozapine. These data are consistent with a neurodevelopmental model of schizophrenia and with some kind of progressive neurodegenerative process. This review suggests that an integrative model with initial developmental errors may underlie the majority of cases of schizophrenia, but that cases of chronic schizophrenia appear to involve progressive neurodegeneration. In assessing the scatter in available data, it appears that there is no consistent neuropathology across all cases of schizophrenia and preferential areas of dysfunction can be determined. Thus, there seems a collection of subtle neurodevelopmental errors which can lead to various forms of schizophrenia and that at least some types of schizophrenia most probably also involve a neurodegenerative process which could in fact be a consequence of the initial developmental defect.

Brain↗
PubMed2006

Could neuroimaging help us to interpret the clinical effects of acupuncture?

One of the problems in assessing acupuncture efficacy has been the lack of a standardised placebo/control. Despite the lack of 'proof', acupuncture is widely used; hence it would seem that a large proportion of the public are not too concerned with the question of efficacy. Patients and researchers approach the issue of whether acupuncture "works" in an entirely different way. It may be that the management of chronic pain as a whole is largely context driven and non-specific. Therefore, research should focus on areas such as pragmatic/comparative trials and the non-specific effects of treatment. Improving our understanding of the neural mechanisms and substrates of acupuncture, placebo and non-specific effects might enable us to better define a "true placebo" and improve trial design. Imaging studies, however, need to be much more pragmatic. Because of the large overlap in areas of brain activated through acupuncture, pain, placebo and non-specific factors, separating these out in an attempt to pinpoint the mechanisms behind acupuncture will be difficult. Ultimately we need a balance between efficacy, comparative and mechanistic trials using imaging work to inform the whole picture. A broader view of research is therefore necessary to yield meaningful answers and we need to look at the whole package that acupuncture delivers.

Acupuncture Therapy↗