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PubMed2004

[Postural imbalance in patients with vascular brain pathology].

Using MRI survey, 163 patients with various brain pathology of vascular genesis were studied. Vascular dementia according to NINDS-AIREN classification was diagnosed in 15% of patients. Cognitive disturbances in other patients did not reach a level of dementia. A control group comprised 61 subjects without rough structural changes on MRI and cognitive dysfunction. Motor disorders were estimated according to classification of J. Nutt et al. (1993), quantitative static changes were registered using computer stabilography. The results of the study showed that postural instability occurs in 100% of patients with vascular brain pathology. A degree of its expression elevated in direct proportion to the expression of cognitive disturbances, reaching a maximum in patients with dementia.

Adult↗
PubMed2001

[Differential diagnosis of bone and soft tissue tumors by MRI].

Musculoskeletal neoplasms are rare, and both the medical history and complaints of the patients are usually uncharacteristic and of limited information. After a clinical evaluation and biplane conventional radiography, the clinician must classify the patient as having a nonprogressive or progressive primary benign, primary malignant, or metastatic bone tumor. In the case of a probably benign, nonprogressive bone tumor, the patient has to be observed continuously or an additional biopsy should be performed. In the case of a probably malignant lesion, the patient should be referred for further staging and treatment to an orthopedic oncologist. Conventional biplane radiography, scintiscan, computed tomography scan, and magnetic resonance imaging (MRI) are indispensable in staging and treatment planning for patients with musculoskeletal tumors. For limb salvage procedures, delineation of the tumor from adjacent tissue structures is crucial. Hence, MRI of the entire anatomic structure involved, together with adjacent joints, is of the utmost importance, both in the coronal and axial planes. The significance of MRI in clinical follow-up depends on keeping the sequences and imaging planes used constant. Differentiating pseudotumors from true neoplasms still poses a challenge. The cellular pattern and matrix characteristics of a lesion cannot definitely be identified as neoplastic even with application of all imaging modalities including MRI. Information on epidemiology, clinical picture, radiology, and histology of the lesion is necessary to draw a firm conclusion. Biopsy is still the first choice in making the diagnosis.

Adult↗
PubMed1998

Cerebral perfusion impairment in a patient with toluene abuse.

We report the case of a 17-yr-old man diagnosed as a toluene abuser. He had an 8-mo history of toluene inhalation exposure and was admitted to this hospital with symptoms of auditory and visual hallucination. Magnetic resonance imaging (MRI) revealed no structural abnormalities both on T1- and T2-weighted images, whereas SPECT using 99mTc-ethyl cysteinate dimer (ECD) showed multifocally decreased perfusion in the cerebral cortex, basal ganglia and thalami. Our case indicates that SPECT detects early central nervous system injury from toluene inhalation even when neurological examination and neuroanatomic imaging such as MRI are normal.

Adolescent↗
PubMed2002

MRI analysis of an inherited speech and language disorder: structural brain abnormalities.

Analyses of brain structure in genetic speech and language disorders provide an opportunity to identify neurobiological phenotypes and further elucidate the neural bases of language and its development. Here we report such investigations in a large family, known as the KE family, half the members of which are affected by a severe disorder of speech and language, which is transmitted as an autosomal-dominant monogenic trait. The structural brain abnormalities associated with this disorder were investigated using two morphometric methods of MRI analysis. A voxel-based morphometric method was used to compare the amounts of grey matter in the brains of three groups of subjects: the affected members of the KE family, the unaffected members and a group of age-matched controls. This method revealed a number of mainly motor- and speech-related brain regions in which the affected family members had significantly different amounts of grey matter compared with the unaffected and control groups, who did not differ from each other. Several of these regions were abnormal bilaterally, including the caudate nucleus, which was of particular interest because this structure was also found to show functional abnormality in a related PET study. We performed a more detailed volumetric analysis of this structure. The results confirmed that the volume of this nucleus was reduced bilaterally in the affected family members compared with both the unaffected members and the group of age-matched controls. This reduction in volume was most evident in the superior portion of the nucleus. The volume of the caudate nucleus was significantly correlated with the performance of affected family members on a test of oral praxis, a test of non-word repetition and the coding subtest of the Wechsler Intelligence Scale. These results thus provide further evidence of a relationship between the abnormal development of this nucleus and the impairments in oromotor control and articulation reported in the KE family.

Adolescent↗
PubMed2005

[Brain effects of cannabis--neuroimaging findings].

Cannabis is the most widely used illicit drug. Despite this, only a small number of studies have investigated the long-term neurotoxic consequences of cannabis use. Structural and functional neuroimaging techniques are powerful research tools to investigate possible cannabis-induced pathophysiological changes. A computer literature review was conducted in the MEDLINE and PsycLIT databases between 1966 and November of 2004 with the search terms 'cannabis', 'marijuana', 'neuroimaging', 'magnetic resonance', 'computed tomography', 'positron emission tomography', 'single photon emission computed tomography", 'SPET', 'MRI' and 'CT'. Structural neuroimaging studies have yielded conflicting results. Most studies report no evidence of cerebral atrophy or regional changes in tissue volumes, and one study suggested that long-term users who started regular use on early adolescence have cerebral atrophy as well as reduction in gray matter. However, several methodological shortcomings limit the interpretation of these results. Functional neuroimaging studies have reported increases in neural activity in regions that may be related with cannabis intoxication or mood-change effects (orbital and mesial frontal lobes, insula, and anterior cingulate) and decreases in activity of regions related with cognitive functions impaired during acute intoxication. The important question whether residual neurotoxic effects occur after prolonged and regular use of cannabis remains unclear, with no study addressing this question directly. Better designed neuroimaging studies, combined with cognitive evaluation, may be elucidative on this issue.

Atrophy↗
PubMed2006

Hot water epilepsy with cerebral lesion: a report of five cases with cranial MRI findings.

Hot water epilepsy (HWE) is included in the reflex epilepsies. Although, in general, not common, HWE is concentrated in certain regions of the world. Different bathing habits and genetic factors may be responsible for the high incidence of HWE in these regions. However, the exact pathogenesis of HWE is not known. The facts that complex partial seizures are the most common clinical presentation and EEG recordings show an epileptic focus in the temporal lobe suggested the presence of a structural lesion in the temporal lobe. To our knowledge, however, there were no demonstrable structural changes on MRI and CT scans except in a few case reports. Here, we describe an additional five cases of HWE having an intracranial pathology, for example, hippocampal sclerosis, dysplasia, and a huge cystic lesion. We believe that investigations with new detailed neuroimaging techniques, in addition to experimental and clinical studies, might help us to understand the mechanism of this reflex epilepsy.

Adolescent↗
PubMed2002

Differential rates of regional brain change in callosal and ventricular size: a 4-year longitudinal MRI study of elderly men.

Brain structure changes in size with normal aging, but the rate at which different structures change is controversial. We used magnetic resonance imaging (MRI) performed twice, 4 years apart, to compare rates of age-related size change of the corpus callosum, which has been inconsistently observed to thin with age, with change in the lateral ventricles, which are well established to enlarge. Subjects were 215 community dwelling, elderly men (70-82 years old at initial MRI), who were participants in a longitudinal study of cardiovascular risk factors. Percent change in size was significant for both the callosal and ventricular measures, but annual rate of ventricular expansion (2.9%) was significantly greater than annual rate of callosal thinning (-0.9%). Callosal regions showed statistically equivalent rates of shrinkage; ventricular dilatation was symmetrical. Neither callosal and ventricular rates of change correlated with each other (r = 0.01), nor did genu and splenium rates of change correlate with each other (r = 0.05). Tests of speeded processing were administered contemporaneously with both MRIs to examine functional ramifications of observed brain changes. Decline in the Mini-Mental State Examination was related to thinning of the splenium, and decline in Stroop test word reading was selectively related to thinning of the callosal body. These longitudinal data support the contentions that differential rates of change occur in different brain regions in normal aging, age-related callosal thinning contributes to functional declines, and rate of change in one region can be independent of rate of change in another region, even within a brain structure.

Aged↗
PubMed1990

I-123 Iofetamine SPECT scan in children with neurological disorders.

I-123 Iofetamine (IMP) single photon emission computed tomography (SPECT) imaging of the brain in 42 patients (ages 14 days to 23 years) was compared with other localizing studies in children with neurological diseases. All had an EEG and at least one imaging study of the brain (computed tomography (CT) or magnetic resonance imaging (MRI), or both). Seventy-eight percent of the patients had an EEG within 24-72 hours of the IMP-SPECT scan. Thirty-five (83%) had a history of seizures, and the remainder had other neurological conditions without a history of seizures. In most cases, a normal EEG reading with normal CT or MRI result predicted a normal SPECT study. When the EEG was abnormal the majority of the IMP-SPECT scans were abnormal and localized the abnormality to the same region. A comparison with CT and MRI showed that structural abnormalities involving the cortex were usually well demonstrated with IMP-SPECT imaging. Structural lesions confined to the white matter were generally not detectable with IMP-SPECT. In a few cases, SPECT scans revealed abnormalities in deep brain areas not identified by EEG. IMP-SPECT imaging is a valuable technique for the detection and localization of abnormal cerebral metabolic activity in children with seizure disorders. A correlation with CT or MRI is essential for proper interpretation of abnormalities detected with IMP SPECT imaging.

Adolescent↗
PubMed2001

In-vivo tissue characterization of multiple sclerosis and other white matter diseases using magnetic resonance based techniques.

In several white matter diseases of the central nervous system (CNS), and in particular in multiple sclerosis (MS), conventional magnetic resonance imaging (MRI) has proved to be sensitive for detecting lesions and their changes over time. However, conventional MRI is not able to characterize and quantify the tissue damage within and outside such lesions. Other quantitative MR techniques, including proton MR spectroscopy (1H-MRS), magnetization transfer MRI (MT-MRI) and diffusion-weighted MRI (DW-MRI) have the potential to overcome this limitation and, as a consequence, to provide additional information about the nature and the extent of tissue damage, which would be inevitably lost when only conventional MRI is obtained. Metrics derived from MT- and DW-MRI can quantify the structural changes occurring within and outside lesions visible on conventional MRI scans. 1H-MRS could add information on the biochemical nature of such changes. The application of these MR techniques to the study of MS is increasing dramatically our understanding of how MS causes irreversible disability and it is likely to provide useful insights into the pathophysiology of other diseases of the CNS in the near future.

Brain Chemistry↗
PubMed2004

Magnetization transfer magnetic resonance imaging in the assessment of neurological diseases.

In several white matter diseases of the central nervous system (CNS), and in particular in multiple sclerosis, conventional magnetic resonance imaging (MRI) has proved to be sensitive for detecting lesions and their changes over time. However, conventional MRI is not able to characterize and quantify the tissue damage within and outside such lesions. Magnetization transfer MRI (MT-MRI) is a quantitative MRI technique with the potential to overcome this limitation and, as a consequence, to provide additional information about the nature and the extent of tissue damage. Metrics derived from MT-MRI can quantify the structural changes occurring within and outside lesions visible on conventional MRI scans. The present review summarizes the major contributions given by MT-MRI to provide an accurate in vivo picture of the heterogeneity of CNS pathology and, ultimately, to improve our ability to monitor the evolution of various neurological conditions.

Central Nervous System Diseases↗
PubMedDate not supplied

MR-based technology for in vivo detection, characterization, and quantification of pathology of relapsing-remitting multiple sclerosis.

In relapsing-remitting (RR) multiple sclerosis (MS), conventional magnetic resonance (MR) imaging (MRI) has proved to be a valuable tool to assess the lesion burden and activity over time. However, conventional MRI cannot characterize and quantify the tissue damage within and outside such lesions and only can provide some gross measures reflecting the presence of irreversible tissue damage, such as the load of T1 "black holes" and the severity of brain or cord atrophy. Other MR-based techniques, including cell-specific imaging, magnetization transfer (MT) MRI (MT-MRI), diffusion-weighted (DW) MRI (DW-MRI), proton magnetic resonance spectroscopy (1H-MRS), and functional MRI (fMRI), have the potential to overcome this limitation and, consequently, to provide additional information about the nature and the extent of MS tissue damage, which would inevitably remain undetected when only a conventional MRI is obtained. Cell-specific imaging should result in a better definition of the cellular mechanisms associated with MS inflammation. Metrics derived from MT- and DW-MRI can quantify the structural changes occurring within and outside lesions visible on conventional MRI scans. 1H-MRS could add information on the biochemical nature of such changes. fMRI is a promising technique to assess the mechanisms of cortical reorganization, which may limit the consequences of an MS-related injury. The application of these MR techniques to the study of RRMS is likely to provide useful insights into the pathophysiology of this disease and to improve our ability to assess the efficacy of experimental treatments.

Biopsy, Needle↗
PubMed2001

Structural and functional cortical abnormalities after upper limb amputation during childhood.

Functional reorganization has been well documented in the human adult brain after amputation of the arm. To assess the effects of amputation on the developing brain, we investigated six patients with upper limb amputation in early childhood and one with right dysmelia. Transcranial magnetic stimulation indicated contralateral cortical disinhibition and enlargement of the excitable area of the stump. FMRI data corroborated these plastic changes and also showed an ipsilateral functional reorganization. In the T1-weighted MRI, we found structural deformities of the contralateral and ipsilateral central sulcus in three patients and a contralateral atrophic parietal lobule in two patients. Therefore, arm amputation in childhood affects functional organization as well as anatomical structure in both hemispheres.

Adolescent↗
PubMed2006

The role of FDG-PET, ictal SPECT, and MEG in the epilepsy surgery evaluation.

2-[18F]Fluoro-2-deoxy-d-glucose positron emission tomography (FDG-PET), ictal single-photon-emission computed tomography (ictal SPECT), and magnetoencephalography (MEG) represent three established functional imaging tests that offer unique information toward the localization of epilepsy for surgery evaluation and treatment. When these tests are combined with high-resolution magnetic fresonance imaging (MRI), epilepsy related structure and function disturbances may be localized with a degree of confidence and understanding not possible with electroencephalography (EEG), even ictal recordings with intracranial electrodes, the mainstay of tools for seizure localization. Use of these alternative tests allows an increased percentage of patients to be considered for surgical treatment. In particular, the additional information provided by these techniques has been demonstrated to help those patients with nonlocalizing MRI or extratemporal lobe epilepsy. Studies that address optimal use of these tests (alone and in combination) will build toward the next major advancement in the surgical treatment of epilepsy by allowing better patient selection, less risk, and better surgical outcomes. Ultimately, appropriate use of these tests, combined with more comprehensive functional brain mapping (e.g., with MEG or functional MRI), may lead to completely noninvasive epilepsy surgery evaluation.

Epilepsy↗
PubMed2002

[Mild cognitive impairment: imaging data].

The diagnosis of Mild Cognitive Impairment (MCI) as defined by Petersen et al. (1997), is based uniquely on clinical observations. Cerebral imaging, both morphological and functional, may in fact facilitate diagnosis, particularly with regard to the differentiation of sub-types of MCI and the identification of prodromal AD (MCI-AD). Volumetric Magnetic Resonance Imagery (MRI) examination of structures affected early in AD such as entorhinal cortex, the temporal lobe and, above all, the hippocampus, are especially useful. Hypoactivity within these regions, especially of the temporal lobe and posterior cingulate gyrus by Positon Emission Tomography, and more recently monophotonic emission tomoscintigraphy, also appears to have diagnostic utility. Studies of cholinergic system activity by functional imaging may also be of future value in MCI-AD diagnosis. MRI used in conjunction with other techniques may be of significant value, in particular the use of spectro-MRI and functional MRI. This latter technique, leading to the development of cognitive activation paradigms, is particularly promising.

Aged↗
PubMed2004

Cardiac involvement in Mulibrey nanism: characterization with magnetic resonance imaging.

Mulibrey nanism (MUL) is an autosomal recessive disorder that is enriched in the Finnish population. Variable degrees of pericardial and myocardial involvement can lead to heart failure and premature death. The purpose of this study was using magnetic resonance imaging (MRI) to assess structural and functional abnormalities of the MUL cardiopathy in all four cardiac chambers as well as in the pericardium. Thirty-one patients with MUL (mean age 27, range 15-50 years) and 16 controls (mean age 31, range 19-45 years) were examined with a Siemens Vision 1.5-T imager. Ten patients had undergone pericardiectomies to relieve symptoms of constrictive pericarditis. In surgery performed 0.5-25 years before MRI, the removed pericardium was found to be thickened and consisting of scarlike fibrosis. Turbo spin echo images were obtained for assessment of pericardial thickness, and breath hold left ventricular (LV) short axis and four-chamber cine images were obtained for the volumetric data. In MRI, pericardial thickness was normal (under 3.4 mm) in all patients with MUL. In the 10 pericardiectomized patients, the remnants of the pericardium were of normal thickness as well. The LV septum (p = 0.01) and posterior wall (p<0.001) were hypertrophied and end-diastolic volumes of both ventricles (p<0.05) were reduced in all patients. The LV systolic function was preserved. The volume chance during the first third of diastole (p = 0.030), the absolute peak filling rate (p = 0.047), and the time to peak rate of LV diastolic filling (p = 0.030) indicated restrictive LV diastolic filling. The right ventricular ejection fraction and contraction of both atria were reduced.

Adolescent↗
PubMed1991

Brain imaging in dementia of the Alzheimer type.

Neuroimaging modalities have increased understanding of brain abnormalities in dementia of the Alzheimer type (DAT), and is important in assessment of dementia syndromes by revealing focal disorders, demonstrating potentially treatable conditions, and by documenting progression of disease severity. Computed tomography (CT) and magnetic resonance imaging (MRI) have delineated structural changes in DAT, including cerebral atrophy associated with cortical sulci widening and ventricular enlargement, and deep white-matter lesions with periventricular distributions. Positron emission tomography (PET) has demonstrated diminished regional glucose metabolism at parietal and temporal lobes in DAT, while frontal hypometabolism tends to occur in more severe cases. Metabolic dysfunction assessed by PET appears to be the first indication of a degenerative cortical process in DAT, while anatomic changes on CT or MRI may become evident later in the disease process. This selective overview provides an analysis of the current status and future prospects of brain imaging in DAT.

Alzheimer Disease↗
PubMed2004

Whole-Organ Magnetic Resonance Imaging Score (WORMS) of the knee in osteoarthritis.

OBJECTIVES: To describe a semi-quantitative scoring method for multi-feature, whole-organ evaluation of the knee in osteoarthritis (OA) based on magnetic resonance imaging (MRI) findings. To determine the inter-observer agreement of this scoring method. To examine associations among the features included in the scoring method. METHODS: Nineteen knees of 19 patients with knee OA were imaged with MRI using conventional pulse sequences and a clinical 1.5 T MRI system. Images were independently analyzed by two musculoskeletal radiologists using a whole-organ MRI scoring method (WORMS) that incorporated 14 features: articular cartilage integrity, subarticular bone marrow abnormality, subarticular cysts, subarticular bone attrition, marginal osteophytes, medial and lateral meniscal integrity, anterior and posterior cruciate ligament integrity, medial and lateral collateral ligament integrity, synovitis/effusion, intraarticular loose bodies, and periarticular cysts/bursitis. Intraclass correlation coefficients (ICC) were determined for each feature as a measure of inter-observer agreement. Associations among the scores for different features were expressed as Spearman Rho. RESULTS: All knees showed structural abnormalities with MRI. Cartilage loss and osteophytes were the most prevalent features (98% and 92%, respectively). One of the least common features was ligament abnormality (8%). Inter-observer agreement for WORMS scores was high (most ICC values were >0.80). The individual features showed strong inter-associations. CONCLUSION: The WORMS method described in this report provides multi-feature, whole-organ assessment of the knee in OA using conventional MR images, and shows high inter-observer agreement among trained readers. This method may be useful in epidemiological studies and clinical trials of OA.

Aged↗
PubMed2004

Review on structural neuroimaging findings in autism.

Autism is now widely viewed as a neurodevelopmental disorder, although the underlying biological causes remain to be established. In this review, we examine the literature in magnetic resonance imaging (MRI) as applied to autism, discuss the findings that have emerged, and give directions for potential future research. To date, structural MRI results are inconsistent, partly due to the heterogeneity of the disorder itself, and partly due to the different composition and the varied degree of matching of the studied groups. However, recent studies have begun to elucidate the underlying neuroanatomical abnormalities and brain-behavior relationships in autism, with the most consistent finding being increased brain volume in autism. Future large-scale longitudinal structural imaging studies, starting at very young ages, investigating homogeneous groups of patients and extensively matched control groups, and making use of (combinations of) newer and more sophisticated techniques, hold a great promise to further elucidate the enigma of autism.

Age Factors↗