Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “MATTER”

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 505 records · Page 28Linked to original sources
PubMed2002

Smaller frontal gray matter volume in postmortem schizophrenic brains.

OBJECTIVE: The prefrontal cortex exhibits prominent functional, biochemical, and anatomic abnormalities in schizophrenic patients. However, smaller than normal volume of the frontal lobe has not been found in previous postmortem studies of schizophrenic subjects, and magnetic resonance imaging (MRI) scans of schizophrenic subjects have not consistently revealed frontal volumetric deficits. The variability in MRI findings may be related partly to difficulty in defining the posterior border of the frontal lobe. In this study, precise measurements of frontal lobe volume from postmortem brains were derived by defining the posterior border according to the brain atlas of Talairach and Tournoux and by applying stereologic methods to estimate gray and white matter volumes. METHOD: Whole, or nearly whole, formalin-fixed left hemispheres from 14 schizophrenic and 19 normal comparison subjects were analyzed. Total cortical gray and white matter volumes, as well as frontal cortical gray and white matter volumes, were measured by using the Cavalieri method. RESULTS: Only frontal gray matter volume was significantly smaller in the schizophrenic subjects than in the comparison subjects (12% difference). The differences between groups in total gray and white matter volumes and frontal white matter volume (6%-8% smaller in the schizophrenic subjects than in the comparison subjects) did not reach statistical significance. CONCLUSIONS: The smaller frontal gray matter volume observed in schizophrenic brains suggests that pathology of the frontal lobe may be more severe than that of the three posterior lobes and may account for the prominence of prefrontal dysfunction associated with schizophrenia.

Adult↗
PubMed2002

Elevated free radical products in the cerebrospinal fluid of VLBW infants with cerebral white matter injury.

Free radical mediated cellular injury has been hypothesized to play a key role in the pathogenesis of white matter injury in the premature infant, although direct evidence is lacking. Between April 1999 and May 2001, 22 very low birthweight infants, 30 term infants, and 17 adults had samples of cerebrospinal fluid (CSF) collected for clinical indications. Only CSF samples without any evidence of meningeal inflammation were analyzed for the levels of the lipid peroxidation products, 8-isoprostane and malondialdehyde (MDA), and protein carbonyls as a measure of protein oxidation. Chlorotyrosine was monitored as a measure of neutrophil oxidative activity. In the premature infants with subsequent evidence of white matter injury on magnetic resonance imaging at term, there was a significant elevation in the CSF level of protein carbonyls in comparison with the level in healthy premature infants, term infants, and adult controls (all p < 0.001). A significant difference in the levels of the lipid peroxidation products, 8-isoprostane and MDA, was apparent between premature infants with white matter injury and adult controls (isoprostanes p = 0.02, MDA p = 0.014). There was a trend toward higher levels of 8-isoprostane in the premature infants with white matter injury in comparison with those without white matter injury (p = 0.08), with 5 of the 14 infants with white matter injury having levels that were more than 10-fold higher than the top of the adult range. There was no significant difference in the level of chlorotyrosines among any of the groups. These preliminary data provide evidence of an association of elevated oxidative products during the evolution of white matter injury in the human premature infant.

Biomarkers↗
PubMed2006

Effects of first trimester binge alcohol exposure on developing white matter in fetal sheep.

Heavy prenatal alcohol exposure is associated with neurodevelopmental abnormalities. Neuropathologic and neuroimaging studies have shown a wide range of structural problems, including abnormal neuronal migration and volume reduction in specific brain regions, including white matter. We identified foci of significant fetal white matter microglia-macrophage immunoreactivity in a "binge" model of early prenatal alcohol exposure in sheep. Ewes of alcohol-exposed fetuses received daily 90 min alcohol (1.5 gm/kg i.v.) infusions at 30-60 d gestation (term = 147 d). Ewes of control fetuses received same volume infusions of normal saline intravenously. Near-term (125 d gestation) fetal brains were labeled with microglia-macrophages using HAM56 antibody. We quantified dense immunoreactive cellular regions across sections and anatomical locations using computer-assisted microscopy and quantitative morphometry. The proportional HAM56-positive area in cortical white matter was greater in the alcohol-exposed fetuses (1.6%) compared with the saline controls (0.7%). The areas were localized to the frontal gyral white matter, temporal gyral white matter, optic radiation, and others (corpus callosum, septum pellucidum, fasciculus subcallosus, and external capsule), with a greater distribution in the gyral white matter. The greater area of macrophage-rich regions in near-term fetal sheep brain suggests a vulnerability of developing white matter that is enhanced by early alcohol exposure.

Alcohol Drinking↗
PubMed2002

Megalencephaly in NF1: predominantly white matter contribution and mitigation by ADHD.

BACKGROUND: Megalencephaly is a frequent CNS manifestation in neurofibromatosis type 1 (NF1); however, its tissue composition, modification by attention deficit hyperactivity disorder (ADHD), and relationship with unidentified bright objects (UBO) remain controversial. METHODS: Eighteen male patients with NF1, seven of whom had ADHD (NF1+ADHD), were compared with 18 age- and sex-matched controls in terms of MRI-, Talairach-based brain, cerebral, lobar, and sublobar gray and white matter volumes. Twelve subjects with NF1 had UBO in the centrencephalic region, whereas six had no UBO or exclusively infratentorial lesions. RESULTS: Patients with NF1 without ADHD (NF1-pure) had the largest total cerebral, gray, and white matter volumes with larger parietal/somatosensory white matter volumes than controls, particularly if UBO were present in the basal ganglia. All subjects with NF1 (including NF1+ADHD) had larger total and frontal white matter volumes than controls. Smaller frontal/right prefrontal gray matter volumes were found in NF1+ADHD when compared with NF1-pure patients. CONCLUSIONS: The increase in frontal and parietal white matter volumes in male patients with NF1, including the preferential centrencephalic distribution, supports the hypothesis that NF1's white matter pathology encompasses but is not limited to visible UBO. Male patients with NF1+ADHD, as compared with NF1-pure patients, showed frontal reductions that are largely consistent with those found in idiopathic ADHD.

Adolescent↗
PubMed2006

White matter damage on diffusion tensor imaging correlates with age-related cognitive decline.

BACKGROUND: Damage to white matter tracts, resulting in "cerebral disconnection," may underlie age-related cognitive decline. METHODS: Using diffusion tensor MRI (DTI) to investigate white matter damage, and magnetic resonance spectroscopy (MRS) to look at its underlying pathologic basis, the authors investigated the relationship between white matter structure and cognition in 106 healthy middle-aged and elderly adults. Fractional anisotropy (FA) and mean diffusivity (MD) values, whole brain white matter histograms, and regions of interest placed in the white matter of the centrum semiovale were analyzed. Correlations with executive function, working memory, and information-processing speed were performed. RESULTS: There was a progressive reduction in FA and increase in diffusivity with age in both region of interest (r = 0.551, p < 0.001), and whole brain histograms (r = 0.625, p < 0.001). DTI values correlated with performance in all three cognitive domains. After controlling for age, DTI parameters correlated with working memory but not with the other two cognitive domains. MRS studies found a correlation of N-acetyl aspartate, a neuronal marker, with DTI parameters (r = 0.253, p < 0.05). CONCLUSION: The results are consistent with white matter damage due to axonal loss, causing age- related cognitive decline. Working memory may be particularly dependent on complex networks dependent on white matter connections.

Aged↗
PubMed1999

MRI white matter hyperintensities: three-year follow-up of the Austrian Stroke Prevention Study.

OBJECTIVE: To determine the rate, clinical predictors, and cognitive consequences of MRI white matter hyperintensity evolution over 3 years. METHODS: In the setting of the Austrian Stroke Prevention Study, 1.5-T MRI was performed at baseline and at a 3-year follow-up in 273 community-dwelling elderly (mean age, 60+/-6.1 years) without neuropsychiatric disease. At each visit individuals underwent a structured clinical interview and examination, EKG, echocardiography, extensive laboratory workup, and demanding neuropsychological testing. MR images were read by three independent raters, and the change of white matter hyperintensities from baseline was assessed by direct image comparison. The change was graded as absent, minor, or marked. Minor change was defined as a difference of no more than one to four punctate lesions between both scans. A change was considered to be marked if there was a difference of more than four abnormalities or a transition to early-confluent and confluent lesions. RESULTS: Combined ratings indicated lesion progression in 49 individuals (17.9%). Lesion progression was minor in 27 participants (9.9%) and was marked in 22 (8.1%). Regression of white matter hyperintensities did not occur. Diastolic blood pressure (odds ratio, 1.07/mm Hg) and early-confluent or confluent white matter hyperintensities at baseline (odds ratio, 2.62) were the only significant predictors of white matter hyperintensity progression. Lesion progression had no influence on the course of neuropsychological test performance over the observational period. CONCLUSIONS: White matter hyperintensities progress in elderly normal subjects. Our data may be used as a reference for future observational and interventional studies on white matter hyperintensity progression in various CNS diseases. The lack of an association between lesion progression and cognitive functioning needs to be explored further.

Aged↗
PubMed2000

Atrial fibrillation and the risk of cerebral white matter lesions.

BACKGROUND: Cerebral white matter lesions are often observed on MRI scans of elderly nondemented and demented persons. Their pathogenesis is not fully understood but cerebral hypoperfusion may be involved. Atrial fibrillation is a common finding in elderly subjects and may lead to a reduced cardiac output with cerebral hypoperfusion. The authors investigated the association between atrial fibrillation and the presence of white matter lesions. METHODS: From 1995 through 1996, the authors randomly sampled 1077 subjects from two ongoing prospective population-based studies. From each participant, an electrocardiogram (ECG) was recorded; atrial fibrillation and left ventricular hypertrophy were diagnosed with a computer program. For one of the two groups (553 subjects), earlier ECGs were available (mean follow-up 4.7 years). All subjects underwent 1.5-T MRI scanning; white matter lesions were separately rated for the periventricular and subcortical regions. RESULTS: The prevalence of atrial fibrillation was 1.9% among subjects younger than 75 years and 5.5% in subjects older than 75 years. The total number of subjects with atrial fibrillation was 28. Subjects with atrial fibrillation had severe periventricular white matter lesions more than twice as often as subjects who did not (RR 2.2; 95% CI 1.0 to 5.2) but had no increased risk of subcortical white matter lesions (RR 1.1; 95% CI 0.4 to 2.6). For seven subjects with atrial fibrillation both at baseline and at follow up, these relative risks were 6.3 (95% CI 1.1 to 37.1) and 0.7 (95% CI 0.1 to 3.7). CONCLUSIONS: Atrial fibrillation is associated with periventricular white matter lesions, but not with subcortical white matter lesions.

Aged↗
PubMed1998

[White matter changes of corpus callosum in normotensive and hypertensive rats following bilateral carotid artery stenosis].

The pathological mechanism responsible for cerebral white matter lesions, frequently observed in elderly individuals, is supposed to be chronic cerebral hypoperfusion Vascular risk factors such as hypertension and carotid artery stenosis are usually involved in these lesions. The objective of this study was to elucidate the role of hypertension in white matter changes using a bilateral carotid artery stenosis model. To induce cerebral hypoperfusion, chronic stenosis was produced by placing a 3 mm long polyethylene cuff around the bilateral carotid arteries of normotensive Wistar rats (Wistar) and spontaneously hypertensive rats (SHR). Two different diameters of tube, PE-50 (inside diameter 0.58 mm) and PE-60 (inside 0.76 mm), were used to induce different degrees of stenosis. The rats were divided into three groups, sham group, PE-50 group, and PE-60 group (each group included 15 Wistar and 15 SHR). At 1,2, and 4 weeks after the operation, pathological changes in which matter were observed in the corpus callosum, and the degree of lesions was assessed using the Vacuole Index. PaO2, PaCO2, pH and mean arterial blood pressure (MABP) were measured prior to and immediately after carotid stenosis. MABP in SHR was significantly higher than in Wistar in all groups (p < 0.05). Other physiological data did not differ significantly between Wistar and SHR. There was no difference in white matter changes between the Wistar sham and SHR sham groups at any time point. There was only a small degree of white matter lesions in the Wistar PE-50 and -60 groups after 4 weeks stenosis, and they did not differ significantly from the sham. In both the SHR PE-50 and -60 groups, however, white matter lesions were slightly apparent at 1 week, and were clearly visible at 4 weeks. The degree of lesions in the SHR PE-50 was significantly higher at 1 week than in the sham (p < 0.01), and both the sham and the Wistar PE-50 at 2 and 4 weeks (p < 0.01), and the SHR PE-60 at 4 weeks (p < 0.01). The SHR PE-60 also had significantly more lesions than the sham at 2 weeks (p < 0.05), and both the sham and the Wistar PE-60 at 4 weeks (p < 0.01). These findings indicate that both hypertension and chronic hypoperfusion play important roles in the development of white matter lesions.

Animals↗
PubMed2003

Lowered electroencephalographic spectral edge frequency predicts the presence of cerebral white matter injury in premature infants.

OBJECTIVE: Current methods for early identification of cerebral white matter injury in the premature infant at the bedside are inadequate. This study investigated the utility of advanced spectral analysis of the neonatal electroencephalogram (EEG) in the early diagnosis of white matter injury in the premature infant. The critical measurement used, suggested largely by previous studies in animal models, was the spectral edge frequency (SEF), calculated here as the frequency below which 90% of the power in the EEG exists. METHODS: Fifty-nine very low birth weight infants (87% of eligible infants) had electrodes placed over the central and parietal regions (C3, P3, C4, and P4 sites according to the 10-20 international system) for the collection of EEG amplitude, intensity, and SEF. All averaged signals were analyzed off-line using software (Chart Analyzer; BrainZ Instruments, Auckland, NZ). All infants had a magnetic resonance imaging scan at term to identify the presence and severity of white matter injury. RESULTS: There was no significant difference between conventional EEG amplitude and intensity for infants with or without evidence of white matter injury. However, premature infants with increasingly severe white matter injury had progressively lower SEFs compared with infants who did not exhibit white matter injury. CONCLUSIONS: These data suggest that SEF-based measures are useful for defining the presence and severity of white matter injury at the bedside.

Analysis of Variance↗
PubMedDate not supplied

Virus retention and transport as influenced by different forms of soil organic matter.

Organic materials are widespread in natural soil and aquatic environments. Their effect on virus transport is very important in assessing the risk for contamination of ground water by viruses. This study aimed to determine how different forms (mineral-associated and dissolved) of natural organic matter influence the retention and transport of two bacteriophages (MS-2 and phiX174) in two porous media (a sand and a soil). We found that mineral-associated organic matter significantly promoted the transport of one virus (MS-2) but not the other (phiX174) in a phosphate-buffered saline solution. Similarly, MS-2 was retained less in sand columns with increasing concentrations of dissolved humic acid, while little effect was observed for phiX174 under the same conditions. The two viruses have different surface properties and thus exhibited different reactivity to the metal oxides present on sand particles and were affected differently by organic matter. Because the organic matter used in the study was negatively charged and hydrophilic, blocking of virus sorption sites and increasing of virus-medium electrostatic repulsion arising from modification of the sand and virus surface by organic matter are probably responsible for the facilitated transport. For dissolved humic acid, its competition for sorption sites with viruses was an additional mechanism involved. This study suggests that the effect of organic matter varied depending on the organic material properties and the type of viruses involved. As a general trend, the effect of organic matter was dominated by electrostatic rather than hydrophobic interactions.

Adsorption↗
PubMed1991

The location of spinothalamic axons within spinal cord white matter in cat and squirrel monkey.

The locations of spinothalamic (STT) fibers in the spinal cord white matter have been identified in cat and squirrel monkey by light-microscopic visualization of labeled fibers following multiple thalamic injections of wheatgerm agglutinin conjugated to horseradish peroxidase. Thalamic injections were combined with either a constricting dural tie or an intraspinal injection of colchicine to facilitate axonal labeling at more rostral spinal levels. In the cat, the ventral-to-dorsal distribution of labeled STT fibers was bimodal. In the ventrolateral white matter, labeled axons were coarse in nature and were primarily concentrated peripherally. In the dorsolateral white matter, labeled STT axons consisted of fine-caliber fibers concentrated in the ventral portion of the dorsolateral funiculus and were equally distributed throughout the medial and lateral white matter. In the squirrel monkey, the distribution of STT fibers was unimodal, extending from the ventral surface of the spinal white matter to the ventralmost portion of the dorsolateral funiculus. As in the cat, however, the ventrally located axons were large and coarse and were primarily located in the peripheral white matter, whereas the dorsalmost STT fibers were of fine caliber and were distributed equally in the medial and lateral white matter.

Animals↗
PubMed1991

[The relationship between cerebral white matter changes, mental function and blood pressure in normal elderly].

The authors examined the relationship between cerebral white matter changes and mental function, blood pressure in 39 neurologically normal aged (21 males, 18 females, mean age 75.0 years) who had no latent lesions on MRI images. The severity of cerebral white matter changes was estimated by T1 value images on MRI and was measured in the bilateral frontal lobe on an axial slice at the level of the basal ganglia and in the bilateral anterior, middle, and posterior portions on axial slices at the level of the body of the lateral ventricle. Mental function was measured by the Hasegawa's dementia rating scale (HDS) and Kohs' block design test (Kohs' test). The severity of cerebral frontal white matter changes increased significantly with age (p less than 0.05). However there was no significant correlation between the severity of cerebral white matter changes and HDS, Kohs' test. The severity of frontal white matter changes correlated with the mean arterial blood pressure (p less than 0.02). These results suggest that the severity of cerebral white matter changes is not related with mental function in the normal elderly, and that the severity of frontal white matter lesions is related with mean arterial blood pressure.

Adult↗
PubMed1996

[Diffusional anisotropy in cerebral white matter in patients with dementia].

We studied changes in water diffusion in cerebral white matter in 10 patients with Binswanger's disease (BD), 8 patients with Alzheimer's disease (AD) who had periventricular hyperintensity lesions on T2-weighted images, and 8 age-matched controls. The apparent diffusion coefficients measured in the anterior and posterior white matter were significantly higher in the patients than in the controls, but there was no significant difference between patients with BD and those with AD. The anisotropy ratios, difined as diffusion perpendicular to the nerve fiber direction, were higher in the patients than in the controls. The anisotropy ratio in the anterior white matter was significantly higher in patients with BD than in those with AD, while in the posterior white matter the ratio was significantly higher in patients with AD than in those with BD. These results suggest that in BD and AD cerebral white matter lesions such as periventricular hyperintensity lesions reflect a loss of myelin and axons, and that loss of myelin occurs preferentially in the anterior white matter in BD and in the posterior white matter in AD.

Aged↗
PubMed2006

Relationship of cognitive measures and gray and white matter in Alzheimer's disease.

OBJECTIVE: To examine the relationship between commonly used screening cognitive measures with gray and white matter integrity in patients with mild to moderate AD. BACKGROUND: New neuroimaging techniques, such as voxel-based morphometry (VBM), make it possible to study the relationship between structural brain integrity and cognitive functioning in AD. METHODS: Gray and white matter integrity was evaluated using VBM in fifteen patients with mild to moderate AD. ADAS-Cog and MMSE scores were also performed as part of the baseline assessment for a larger clinical trial in the AD patients. Correlations between cognitive measures and VBM were performed. RESULTS: Both the ADAS-Cog and the MMSE showed a similar relationship with gray matter degeneration, reflecting greater cognitive impairment with decreased gray matter in the left temporal lobe. However, the MMSE score was much more reflective of underlying white matter changes than ADAS-Cog scores, particularly in frontotemporal region. These findings suggest that the ADAS-Cog and MMSE reflect different aspects of the underlying brain changes observed in AD. The ADAS-Cog was more specific to gray matter integrity whereas the MMSE reflected a more global reduction in both gray and white matter. CONCLUSIONS: These results support using neuroimaging markers of neural integrity as an important consideration when evaluating treatment efficacy. Furthermore, whole-brain analyses such as VBM help to evaluate neural systems that are not necessarily targeted by the treatment.

Aged↗
PubMed2000

NBQX attenuates excitotoxic injury in developing white matter.

The excitatory neurotransmitter glutamate is released from axons and glia under hypoxic/ischemic conditions. In vitro, oligodendrocytes (OLs) express non-NMDA glutamate receptors (GluRs) and are susceptible to GluR-mediated excitotoxicity. We evaluated the role of GluR-mediated OL excitotoxicity in hypoxic/ischemic white matter injury in the developing brain. Hypoxic/ischemic white matter injury is thought to mediate periventricular leukomalacia, an age-dependent white matter lesion seen in preterm infants and a common antecedent to cerebral palsy. Hypoxia/ischemia in rat pups at postnatal day 7 (P7) produced selective white matter lesions and OL death. Furthermore, OLs in pericallosal white matter express non-NMDA GluRs at P7. Unilateral carotid ligation in combination with hypoxia (6% O(2) for 1 hr) resulted in selective, subcortical white matter injury with a marked ipsilateral decrease in immature and myelin basic protein-expressing OLs that was also significantly attenuated by 6-nitro-7-sulfamoylbenzo(f)quinoxaline-2,3-dione (NBQX). Intracerebral AMPA demonstrated greater susceptibility to OL injury at P7 than in younger or older pups, and this was attenuated by systemic pretreatment with the AMPA antagonist NBQX. These results indicate a parallel, maturation-dependent susceptibility of immature OLs to AMPA and hypoxia/ischemia. The protective efficacy of NBQX suggests a role for glutamate receptor-mediated excitotoxic OL injury in immature white matter in vivo.

Aging↗
PubMed2001

Chemical pathology in brain white matter of recently detoxified alcoholics: a 1H magnetic resonance spectroscopy investigation of alcohol-associated frontal lobe injury.

BACKGROUND: Investigations have suggested that frontal lobe abnormalities are a prominent feature of the alcoholic brain, indicated by impaired neuropsychological performance on tests of frontal lobe function and by reduced frontal lobe volume in neuroimaging and neuropathological examinations. White matter compartment volume loss may underlie observed brain shrinkage and cognitive deficits associated with the frontal lobes, although the nature of this change has not been well-characterized. METHOD: To investigate the susceptibility of frontal lobe white matter to alcohol-associated metabolic change and to understand the nature of alcohol-related white matter injury, 1H magnetic resonance spectroscopy (MRS) was used to measure concentrations of metabolites in frontal white matter (FWM) and parietal white matter (PWM) of recently detoxified alcoholics (RDA) and nonalcoholic controls (CON). Concentrations of N-acetylaspartate (NAA), choline-containing compounds (Cho), myo-inositol (Ins), and creatine plus phosphocreatine (Cr) were measured in 37 RDA (mean age, 40.4 years; mean length of abstinence, 27.9 days) and 15 CON (mean age, 38.0 years). RESULTS: Analysis of variance (ANOVA) revealed a group by region of interest interaction for concentrations of NAA. Simple effects analysis revealed a significant 14.7% reduction in FWM NAA, while NAA levels in PWM were similar in RDA and CON. In addition, RDA had an 11.8% increase (averaged across both regions of interest) in brain white matter Ins relative to CON. Reductions in FWM NAA were associated with a longer drinking history in the RDA group, but this result was not found when both age and drinking history were used to predict the level of FWM NAA. CONCLUSIONS: Alcohol-associated reductions in FWM NAA may be the result of neuronal loss or dysfunction in the metabolism of NAA. While alcohol-induced oxidative stress may cause global brain impairments in the metabolism and subsequent reduction of NAA, the frontal lobes are particularly rich in excitatory amino acid pathways, and axonal damage or destruction secondary to glutamate-mediated excitotoxicity during alcohol withdrawal may cause frontal lobe-specific reductions in NAA. Elevations in brain white matter Ins may reflect astrocyte proliferation as well as an osmotic response to cell shrinkage.

Adult↗
PubMed2001

A longitudinal study of the role and significance of mattering to others for depressive symptoms.

This paper addresses the hypothesis that the experience of mattering to others is inversely related to depressive symptomatology. We also assess the extent to which mattering overlaps or is redundant with other measures of personal and social resources. Based on multivariate analyses of two waves of data from a large urban community sample (n = 1,300), we identify three important findings. First, women experience substantially higher levels of mattering than do men. Therefore, if men and women had equal levels of mattering, women would report even higher depression scores relative to men. Second, it is clear that mattering and sub-dimensions of social support are substantially more confounded among men than among women. Finally, analyses confirm that mattering is conditionally predictive of depression by gender. Specifically, variations in mattering are predictive of depression for women, but not for men. This relationship is confirmed both cross-sectionally and over time.

Cross-Sectional Studies↗
PubMed2004

[Value of magnetization transfer imaging in judging microchanges lesions in normal-appearing white matter of multiple sclerosis].

OBJECTIVE: To explore the value of magnetization transfer imaging (MTI) in judging microscopic lesions in normal-appearing white matter of multiple sclerosis (MS). METHODS: Forty-one patients with brain MS, 17 males and 24 females, aged 13 approximately 65, and 21 healthy people, 8 males and 13 females, aged 18 approximately 57, used as controls underwent magnetic resonance imaging (MRI) using 3D-spoiled grass (3D-SPGR) series, to scan the whole brain with saturated pulses on and off respectively. The signal values were measured directly in the pictures of these 2 series. The formula MTR = (M(0)-MS)/M(0) x 100% was used, where M0 represents the signal value of region of interest with the saturated pulses off, and Ms represents signal value of region of interest with the saturated pulses on, to calculate the MTR value. With reference to T(2)WI imaging, the MTR values of 17 regions of interest (ROI) in the normal-appearing brain white matter, including the white matter of pons, bilateral cerebellar peduncles, knees of internal capsules, splenium and genu of corpus callosum, and the white matter by the anterior horn and posterior horn of lateral ventricle, body of lateral ventricle, and deep in the frontal and parietal lobes, were measured. The average MTR value of the 17 ROI was used to represent the MTR value of the whole normal-appearing brain and used to make comparison with that of the healthy samples statistically. RESULTS: Compared with those of the healthy samples, the average MTR values of each ROI of the MS patients were lower at different degrees. The difference in the MTR values of the white matter of splenium of corpus callosum, and by lateral ventricle and deep in parietal lobe were especially bigger. The MTR value of the whole brain white matter in the healthy persons ranged from 22.76% to 25.42%, with an average value of 23.97%, both significantly higher than those of the MS patients (19.45% to 24.15%, and 22.44% respectively, both P < 0.05). CONCLUSION: MTI can be used to detect the microchange of normal appearing white matter in MS. MTR is a sensitive indicator to reflect the damage of structure of tissues.

Adolescent↗