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The variability of the severity and regional distribution of pathological process in basal ganglia (BG) and brainstem–cerebellar systems results in clinical heterogeneity and represents the motor subtype of multiple system atrophy (MSA). This study aimed to quantify spatial patterns of multimodal MRI abnormalities in BG and stem-CB regions and define structural MRI findings that correlate with clinical characteristics. We simultaneously measured R2*, mean diffusivity (MD), and volume in the subcortical structures (BG, thalamus, brainstem–cerebellar regions) of 39 probable MSA and 22 control subjects. Principal component analysis (PCA) and structural equation modeling (SEM) were performed to show a model consisting of multiple inter-dependencies. Structural MRI alterations were found to be significantly interrelated within BG as well as brainstem–cerebellar regions in MSA patients. PCA extracted four factors: three factors reflected alterations in R2*, MD and volume of the BG region including the caudate nucleus, putamen, and pallidum, and the remaining one factor represented degenerative changes in MD and volume of stem-CB region. In SEM, a latent variable reflecting brainstem–cerebellar degeneration did not show a significant correlation with the other latent variables associated with BG degeneration. Putaminal MD values and a PCA-driven factor reflecting MD values in the BG showed a significant correlation with UPDRS and UMSARS scores. Multimodal structural MRI abnormalities in MSA appear to be segregated into BG and stem-CB-related factors that can be associated with the clinical phenotype and motor severity.

Background & objective Although iron accumulation is thought to be associated with neurodegenerative processes, the timing of putaminal iron deposition during the disease course of multiple system atrophy (MSA) remains unclear. We sought to investigate the temporal pattern of iron deposition in the putamen of MSA patients by calculating the conditional probabilities (CPs) of multimodal MRI changes. Methods We simultaneously measured putaminal R2*, volume and MD values of 39 probable MSA patients and 22 control subjects. The presence of significant MRI changes was defined as higher R2* and MD values, or lower volumes than cut-off values derived from mean values in control putamen. The CPs of R2* changes without MD or volume changes were then compared with those of MD or volume changes without R2* changes. Results Regardless of the cut-off values, the CPs of R2* increments without MD or volume changes were significantly lower than those for MD or volume changes without R2* increments. The associations of R2* with volume and MD values appeared in non-linear exponential and quadratic patterns, respectively. Conclusions Our findings suggest that putaminal iron accumulation would occur under volume atrophy or MD increments. Thus, iron deposition in the putamen of MSA patients is likely a secondary byproduct of neurodegeneration.

Recently, the level set has become a popular method in many research fields. The main reason is that it can be modified into many variants. One such case is our proposed method. We describe a contrast-enhancement method to segment the hippocampal region from the background. However, the hippocampus region has quite similar intensities to the neighboring pixel intensities. In addition, to handle the inhomogeneous intensities of the hippocampus, we used a bias correction before hippocampal segmentation. Thus, we developed a contrast-enhanced bias-corrected distance-regularized level set (CBDLS) to segment the hippocampus in magnetic resonance imaging (MRI). It shows better performance than the distance-regularized level set evolution (DLS) and bias-corrected distance-regularized level set (BDLS) methods in 33 MRI images of one normal patient. Segmentation after contrast enhancement and bias correction can be done more accurately than segmentation while not using a bias-correction method and without contrast enhancement.

Purpose This study suggests a noninvasive and repetitive measurement method using 1 H magnetic resonance spectroscopy to monitor changes in cellular metabolites within a single sample. Methods Longitudinal acquisition of cellular metabolites from three-dimensional cultured human osteosarcoma (MG-63) cells was conducted using 3.0 Tesla 1 H MRS for 2 weeks at three time points: days 1, 7, and 14. During the MR spectroscopy (MRS) scan, cell specimen temperatures were kept constant at 37°C by a lab-developed magnetic resonance compatible thermostatic device. A DNA assay and live/dead staining of the cell specimens were carried out at each time point to verify the MRS measurements. Results Cell viability in the proposed device did not significantly differ from that of cells in a conventional incubator (P = 0.946). Cell proliferation and choline concentration increased during the first week, but remained constant during the second week. Lactate did not change during the first week, but increased during the second week. Likewise, cell viability remained constant until day 7, then decreased. Conclusion The proposed MRS technique results in a survivable environment for longitudinal studies of cells and provides a new way to measure metabolomic changes over time in single specimens of cells. Magn Reson Med 76:1912-1918, 2016. © 2016 International Society for Magnetic Resonance in Medicine.

Objective We evaluated the differences in brain morphology among patients with juvenile myoclonic epilepsy according to the occurrence of absence seizures. Materials and methods Twenty-one juvenile myoclonic epilepsy patients with (n = 6) and without (n = 15) absence seizures were enrolled. We analyzed whole-brain T1-weighted magnetic resonance imaging using FreeSurfer 5.1. Measures of cortical morphology, such as thickness, surface area, volume, and curvature, and the volumes of subcortical structures, the cerebellum, and cerebrum, were compared between the groups. Moreover, we quantified correlations between clinical variables and each measures of abnormal brain morphology. Results Compared to normal controls, patients without absence seizures demonstrated thinning of the cortical thickness in the right hemisphere, including the post-central, lingual, orbitofrontal, and lateral occipital cortex. Compared to normal controls, patients with absence seizures had more widespread thinning of the cortical thickness, including the right post-central, lingual, orbitofrontal, and lateral occipital cortexes as well as the right inferior temporal cortex. Additionally, the volume of cerebellar white matter in patients without absence seizures was significantly smaller than that in normal controls. Patients with absence seizures had a much smaller cerebellar white matter volume than normal controls or patients without absence seizures. Moreover, there was significantly positive correlation between the age of seizure onset and the volume of cerebellar white matter in patients with juvenile myoclonic epilepsy. Conclusions We demonstrated that there were significant brain morphology differences in patients with juvenile myoclonic epilepsy according to the presence of absence seizures. These findings support the hypothesis that juvenile myoclonic epilepsy may be a heterogeneous syndrome.

This study aimed to investigate the clinical and radiological findings in patients with transient global amnesia and to evaluate structural abnormalities using voxel-based morphometry. The subjects were diagnosed with transient global amnesia. For the voxel-based morphometry analyses, Statistical Parametric Mapping, running on the MATLAB platform (MathWorks, Natick, MA, USA), was employed to analyze the structural differences between patients with transient global amnesia and control subjects. Eighty patients met the inclusion criteria. Twenty-three patients (29%) were men, and 57 patients (71%) were women. There were significantly more women among the transient global amnesia patients compared with the general Korean population. MRI revealed hippocampal cavities in 41 patients (51%), and the incidence of such cavities was significantly different from that of the control subjects (24%). There were no differences in the clinical factors between the patients with and without hippocampal cavities. Diffusion-weighted imaging was performed in 54 patients, and 13 patients (24%) exhibited high signal intensity in the hippocampus. There were also no differences in the clinical factors between the patients with and without high signal intensities in the hippocampus on diffusion-weighted imaging. Twenty-six patients underwent three-dimensional volumetric T1-weighted imaging that produced results suitable for voxel-based morphometry, and these patients presented with gray matter volume reductions in the hippocampus, cingulum, and cerebellum. There were significant structural differences in the limbic structures between patients with transient global amnesia and the control subjects that might have contributed to vulnerability of the memory pathways of the patients with transient global amnesia.

Aims The aim of the present study was to investigate whether the effects of vitamin B12 and homocysteine on brain volume are influenced by apolipoprotein E (APOE) genotype. We examined the effects in each subgroup (APOE e4 carriers and non-carriers) of Alzheimer's disease (AD) patients and healthy normal controls. Methods Forty participants with AD and 20 healthy normal controls were recruited from memory impairment clinics at Pusan National University Hospital in Korea. All participants were APOE genotyped and underwent magnetic resonance imaging, including 3-D volumetric images for grey matter (GM) volume. A multiple regression model integrated into statistical parametric mapping was used to see if there was any correlation between vitamin B12 or homocysteine and GM volume in each subgroup (APOE e4 carriers and non-carriers) of AD patients and healthy normal controls. Results There was a significant positive correlation between serum concentrations of vitamin B12 and regional GM volume in APOE e4 carriers with AD but not in non-carriers. We also found that there was a significant negative correlation between serum concentrations of homocysteine and regional GM volume in APOE e4 non-carriers with AD but not in carriers (P < 0.001, uncorrected for multiple comparisons; extent threshold = 100 voxel). Conclusion The present findings suggest that the effects of vitamin B12 and homocysteine on GM volume might be influenced by APOE genotype.

Background: We evaluated the cortical morphology in patients with orthostatic intolerance. Methods: Thirty patients with orthostatic intolerance, as well as age- and sex-matched normal controls, were enrolled in this study. We divided the patients into orthostatic hypotension (n = 22) and postural tachycardia syndrome (n = 8) groups based on their response to a head-up tilt table test. We analyzed whole-brain T1-weighted MRI images using FreeSurfer 5.1. The measures of cortical morphology were compared between the groups. Results: The cortical thickness in the right hemisphere, including the medial orbitofrontal, peri-calcarine, post-central, inferior temporal, and lateral occipital cortex, and in the peri-calcarine cortex of the left hemisphere was thinned in patients with orthostatic hypotension compared to normal controls. The other measures of cortical morphology, including the surface area, volume, and curvatures, did not differ between patients with orthostatic hypotension and normal controls. However, none of the measures of cortical morphology differed between patients with postural tachycardia syndrome and normal controls. Conclusions: We demonstrated that the cortical morphology significantly changed in patients with orthostatic hypotension but not in patients with postural tachycardia syndrome compared to normal controls. These findings support the hypothesis that orthostatic intolerance is a heterogeneous syndrome.

Objective This study proposes an automated diagnostic method to classify patients with Alzheimer's disease (AD) of degenerative etiology using magnetic resonance imaging (MRI) markers. Methods Twenty-seven patients with subjective memory impairment (SMI), 18 patients with mild cognitive impairment (MCI), and 27 patients with AD participated. MRI protocols included three dimensional brain structural imaging and diffusion tensor imaging to assess the cortical thickness, subcortical volume and white matter integrity. Recursive feature elimination based on support vector machine (SVM) was conducted to determine the most relevant features for classifying abnormal regions and imaging parameters, and then a factor analysis for the top-ranked factors was performed. Subjects were classified using nonlinear SVM. Results Medial temporal regions in AD patients were dominantly detected with cortical thinning and volume atrophy compared with SMI and MCI patients. Damage to white matter integrity was also accredited with decreased fractional anisotropy and increased mean diffusivity (MD) across the three groups. The microscopic damage in the subcortical gray matter was reflected in increased MD. Classification accuracy between pairs of groups (SMI vs. MCI, MCI vs. AD, SMI vs. AD) and among all three groups were 84.4% (±13.8), 86.9% (±10.5), 96.3% (±4.6), and 70.5% (±11.5), respectively. Conclusion This proposed method may be a potential tool to diagnose AD pathology with the current clinical criteria.

The thalamus plays an important role in the modulation of both focal and generalized seizures, but the mechanisms related to seizures may be different among epilepsy syndromes. The aim of this study is to investigate the thalamic atrophy in different epilepsy syndromes. We enrolled a total of 72 patients with epilepsy (22 patients with temporal lobe epilepsy with hippocampal sclerosis, 21 patients with extra-temporal lobe epilepsy, and 29 patients with juvenile myoclonic epilepsy). We analyzed structural volumes of the brain with FreeSurfer 5.1 software, and compared them among subgroups of epilepsy and normal control subjects. Moreover, we quantified correlations between the duration of epilepsy and the structural volumes with age and sex as covariates. The volumes of the ipsilateral hippocampus in temporal lobe epilepsy with hippocampal sclerosis were significantly smaller than those in extra-temporal lobe epilepsy and normal control subjects [analysis of variance (ANOVA), p 0.001]. Although the volumes of the ipsilateral thalamus were not different from those of normal control subjects, the volumes of the ipsilateral thalamus were negatively correlated with duration of epilepsy in temporal lobe epilepsy with hippocampal sclerosis (r = -0.5, p = 0.02). However, the volumes of interest in extra-temporal lobe epilepsy and juvenile myoclonic epilepsy were not different from those in normal control subjects, and none of these structures were correlated with duration of epilepsy. These findings suggest that the role of the thalamus may be different in thalamo-limbic circuits among epilepsy syndromes.

A right-handed 68-year-old man presented with acute-onset memory impairment. Before the event, he was doing well in his daily life. He had a history of hypertension. On the Seoul Neuropsychological Screening Battery, his verbal memory functions exhibited significant impairments (31.82 percentile for immediate recall, 1.09 percentile for delayed recall, and 2.22 percentile for delayed copy). A brain MRI revealed an acute infarction in the left mammillary body (figure 1), and CT angiography revealed focal stenosis of the bilateral posterior cerebral arteries (figure 2).

There have been various studies showing increased iron levels in parkinsonian disorders. The purpose of this study was to demonstrate topographical differences of brain iron deposition between progressive supranuclear palsy (PSP) and the parkinsonian variant of multiple system atrophy (MSA-p) with SWI images.A total of 11 patients with PSP, 12 with MSA-p, 15 with Parkinson's disease (PD), and 20 age-matched healthy controls underwent SWI of the brain. Mean phase shift values of the red nucleus (RN), substantia nigra (SN), head of the caudate nucleus (CN), globus pallidus (GP), putamen (PUT), and thalamus (TH) were calculated and compared between groups. A voxel-based analysis of the processed SWI was performed to determine topographical differences of iron-related hypointense signals in PUT, GP, and TH.Patients with PSP and MSA-p had significantly higher levels of iron deposition than control and PD groups. Comparing patients with PSP and MSA-p, differences were found in iron concentrations of the RN, SN, GP, and TH, which were higher in the PSP group. However, iron levels in the PUT were higher in the MSA group (p0.05). The area under curve (AUC) indicated that the PUT was the most valuable nucleus in differentiating MSA-p from PSP and PD according to phase shift values (AUC=0.836). Meanwhile the GP (AUC=0.869) and TH (AUC=0.884) were the two most valuable nuclei in differentiating PSP from MSA-p and PD. Voxel-based analysis showed subregional differences in iron-related hypointense signals in the PUT, GP, and TH between MSA-p and PSP groups. Patients with MSA-p had significant increases of iron-related hypointense signals in the posterolateral PUT and adjacent lateral aspect of the GP, whereas the PSP group had increased hypodense signals in the anterior and medial aspects of the GP and TH.Our data demonstrate that pathological iron accumulations are more prevalent and severe in PSP compared to MSA-p. The distribution of high-iron-content regions in this study reflects pathoanatomically relevant sites. This finding allows for the use of MRI-based brain iron mapping as a technique to indirectly identify pathological changes.

Although juvenile myoclonic epilepsy has been considered as a disorder of thalamo-cortical circuit, it is not determined the causality relationship between thalamus and cortex. The aim of this study was to evaluate whether juvenile myoclonic epilepsy is a disorder of thalamus or cortex. Twenty-nine patients with juvenile myoclonic epilepsy and 20 normal controls were enrolled in this study. In addition, we included 10 patients with childhood absence epilepsy as a disease control group. Using whole-brain T1-weighted MRIs, we analyzed the volumes of the structures, including hippocampus, thalamus, and total cortex, with FreeSurfer 5.1. We also investigated the effective connectivity among these structures using SPSS Amos 21 based on these volumetric measures. The structural volumes in juvenile myoclonic epilepsy were not different from those in normal controls. There was a statistically significant effective connectivity from the total cortex to the thalamus in the patients with juvenile myoclonic epilepsy. In addition, a significant effective connectivity from the hippocampus to the ipsilateral thalamus was revealed. Unlike the patients with juvenile myoclonic epilepsy, neither the patients with childhood absence epilepsy nor normal controls had a significant effective connectivity from the total cortex to the thalamus or from the thalamus to the cortex. The connectivity of brain in patients with juvenile myoclonic epilepsy could be different from that in patients with childhood absence epilepsy, and the cortex rather than the thalamus might play a critical role in the pathogenesis of juvenile myoclonic epilepsy.

Purpose: To evaluate the temporal and spatial resolution of magnetic resonance (MR) temperature imaging when using the proton resonance frequency (PRF) method combined with the keyhole technique. Materials and Methods: Tissue-mimicking phantom and swine muscle tissue were microwave-heated by a coaxial slot antenna. For the sake of MR hardware safety, MR images were sequentially acquired after heating the subjects using a spoiled gradient (SPGR) pulse sequence. Reference raw (k-space) data were collected before heating the subjects. Keyhole temperature images were reconstructed from full k-space data synthesized by combining the peripheral phase-encoding part of the reference raw data and the center phase-encoding keyhole part of the time sequential raw data. Each keyhole image was analyzed with thermal error, and the signal-to-noise ratio (SNR) was compared with the self-reference (nonkeyhole) images according to the number of keyhole phase-encoding (keyhole-data size) portions. Results: In applied keyhole temperature images, smaller keyhole-data sizes led to more temperature error increases, but the SNR did not decreased comparably. Additionally, keyhole images with a keyhole-data size of

The purpose of this study was to investigate the association between brain regional gray matter volume and two subtypes of psychotic symptoms, namely paranoid and misidentification subtypes, in antipsychotic-naive mild or moderate Alzheimer's disease (AD) patients. Forty AD patients with psychotic symptoms and 25 AD patients without psychotic symptoms were assessed for cognitive and functional impairment. Presence and subtype of psychotic symptoms were assessed by using the delusion and hallucination subscale of the Korean Neuropsychiatric Inventory (K-NPI). Structural MRI images were acquired on a 3 T scanner, and were analyzed using voxel-based morphometry (VBM) for automated analysis. The misidentification subtype is associated with more severe gray matter atrophy, and paranoid subtype is associated with less severe gray matter atrophy compared to non-psychosis group. These results suggest that the misidentification, the paranoid subtype and the non-psychosis group have a distinct neural correlation.

Survivors from cardiorespiratory arrest may develop neurologcal complications, such as post-hypoxic myoclonus (PHM). The hronic type of PHM is known as Lance–Adams syndrome (LAS), hich begins within days to weeks following an episode of anoxia 1]. LAS is characterized by myoclonus, which is triggered by intenional action or external stimuli and relieved at resting state or leep [1]. Several investigations have been performed to determine he pathogenesis of LAS. The loss of the neurotransmitter serotonin ithin the inferior olive has been believed to be an important causal actor for LAS, and gamma-aminobutyric acid may also be involved n the genesis of LAS [2–4]. Recently, neuroimaging has been used o detail the anatomical and pathophysiological basis of LAS [2,3]. evertheless, the pathogenesis of LAS has been not determined. We encountered a patient with LAS and performed resting state unctional MRI (rs-fMRI) to investigate the pathogenesis of LAS.

Objective The purpose of this study was to determine whether gray matter volumes are associated with treatment response of psychotic symptoms in Alzheimer's disease (AD) patients. Method Risperidone, which is commonly used as an atypical antipsychotic drug, was administered in a clinical setting for 6 weeks from April 2012 to February 2013 to 25 antipsychotic-naive AD patients with psychosis, diagnosed according to Jeste and Finkel's proposed diagnostic criteria for psychosis of Alzheimer's disease. Psychotic symptoms were rated with the Korean version of the Neuropsychiatric Inventory (K-NPI) at baseline and at 6 weeks, and treatment response was defined as the change in K-NPI score from baseline to 6 weeks. Gray matter volumes were measured with magnetic resonance imaging and voxel-based morphometry at baseline. Age, gender, years of education, total intracranial volume, apolipoprotein E genotype, dosage of risperidone, the baseline scores on the Korean version of the Mini-Mental State Examination, and the baseline psychotic and nonpsychotic symptoms scores on the K-NPI were measured as covariates of no interest. Results We found that treatment response of psychotic symptoms to risperidone in antipsychotic-naive AD patients was positively associated with both left and right putamina, left parahippocampal gyrus, and left amygdala volume after controlling covariates of no interest (uncorrected P 100 voxels). Conclusions Therefore, we conclude that gray matter volumes of putamina, left parahippocampal gyrus, and left amygdala are associated with treatment response of psychotic symptoms after 6 weeks of treatment with risperidone in antipsychotic-naive AD patients with psychosis. These results suggest that the volumes of specific gray matter regions probably contribute to treatment response of psychotic symptoms in AD patients. Trial registration ClinicalTrials.gov identifier: NCT01198093.

We hypothesize that pre-existing susceptible structures in the brain may be associated with the development of newly diagnosed partial epilepsy of unknown etiology.Twenty-two patients with newly diagnosed partial epilepsy of unknown etiology and 36 healthy controls were enrolled in this study. In addition, we included 24 patients with chronic partial epilepsy of unknown etiology as a disease control group. We analyzed whole-brain T1-weighted MRIs using FreeSurfer 5.1. The volumes of the hippocampus, amygdala, thalamus, caudate, putamen, pallidum, brainstem, cerebellar gray and white matter, as well as cerebral gray and white matter were compared between the groups. We also analyzed the changes in brain volumes associated with the chronicity of epilepsy in the patients with chronic epilepsy compared to newly diagnosed epilepsy.The volume of cerebellar white matter in patients with newly diagnosed epilepsy was significantly smaller than that which was observed in the healthy controls (p=0.0001). This finding was also observed in patients with chronic epilepsy (p0.0001). Cerebral white matter volume was negatively correlated with the duration of epilepsy (r=-0.4, p=0.04).These findings support our hypothesis that cerebellar white matter changes may constitute a pre-existing susceptible structure in the brain that is associated with the development of partial epilepsy of unknown etiology. In addition, cerebral white matter was the structure that was the most vulnerable to the progression of epilepsy.

Purpose To analyze the characteristics of neuropsychological profiles and gray matter volume in de novo, drug-naive Parkinson's disease with mild cognitive impairment (PD-MCI). Methods Fifty-two newly diagnosed PD patients were assessed with neuropsychological testing, and PD-MCI was defined in patients with at least one or more abnormal cognitive test domains. PD with normal cognition (PD-NC) did not meet the criteria for PD-MCI or PD with dementia. Brain MRI scans was acquired from the patients and healthy controls (HC). The imaging processing and analysis of the gray matter (GM) volume were performed platform to determine the difference between PD-MCI and PD-NC. Results There were no differences of motor subscores between PD-MCI and PD-NC. The clinical dementia rating, global deterioration scale, and verbal memory were significantly worse in PD-MCI than in PD-NC. GM volume loss was observed in the right hippocampus, right cuneus, and right precuneus in PD-NC compared to in the HC. PD-MCI had significantly decreased GM volume in the bilateral temporal and frontal areas compared with that of the HC. The GM volume was significantly decreased in the right temporal pole, left precuneus, medial frontal and posterior cingulated gyrus in PD-MCI compared with PD-NC. Conclusions Clinical dementia ratings and global deterioration scales could differentiate PD-MCI from PD-NC. Verbal memory impairment is characterized as a cognitive deficit of de novo PD-MCI and is associated with the posterior cortical area.

The aim of the present study was to investigate whether the effects of vitamin B12 and homocysteine on brain volume are influenced by apolipoprotein E (APOE) genotype. We examined the effects in each subgroup (APOE ε4 carriers and non-carriers) of Alzheimer's disease (AD) patients and healthy normal controls.Forty participants with AD and 20 healthy normal controls were recruited from memory impairment clinics at Pusan National University Hospital in Korea. All participants were APOE genotyped and underwent magnetic resonance imaging, including 3-D volumetric images for grey matter (GM) volume. A multiple regression model integrated into statistical parametric mapping was used to see if there was any correlation between vitamin B12 or homocysteine and GM volume in each subgroup (APOE ε4 carriers and non-carriers) of AD patients and healthy normal controls.There was a significant positive correlation between serum concentrations of vitamin B12 and regional GM volume in APOE ε4 carriers with AD but not in non-carriers. We also found that there was a significant negative correlation between serum concentrations of homocysteine and regional GM volume in APOE ε4 non-carriers with AD but not in carriers (P0.001, uncorrected for multiple comparisons; extent threshold = 100 voxel).The present findings suggest that the effects of vitamin B12 and homocysteine on GM volume might be influenced by APOE genotype.

An association between white matter hyperintensities (WMH) and cognitive dysfunction has long been recognized. However, subjects with identically appearing WMH on magnetic resonance imaging present with a wide variance in cognitive function ranging from normal cognition to dementia. The aim of this study was to compare cortical atrophy and integrity of white matter of patients with subcortical vascular dementia of Binswanger type (SVaD-BT) with those of the normal cognition group with WMH (ncWMH).Eleven patients with SVaD-BT and 11 age-, sex-, education- and grade of WMH-matched ncWMH underwent magnetic resonance imaging, including 3-D volumetric images for cortical atrophy and diffusion tensor imaging for integrity of white matter.Compared to ncWMH, SVaD-BT patients showed cortical atrophies in frontal (i.e. frontal pole, precentral gyrus and frontal medial cortex) and occipital areas (i.e. lingual gyrus) followed by atrophies in temporal (i.e. fusiform cortex and middle temporal gyrus) areas. Along with cortical atrophies, reduced integrity with low fractional anisotropy and high mean diffusivity values in genu and splenium of the corpus callosum were detected in SVaD-BT patients.Our findings suggest that cognitive decline from ncWMH to SVaD-BT may be associated with cortical atrophy and reduced integrity of white matter.

To assess the clinical utility of the breath-hold turbo spin-echo T2-weighted MRI in patients with acute myocardial infarction, the results of MRI were compared with those of electrocardiography, coronary angiography, and thallium-201 single photon emission tomography (SPECT) in 23 patients and 5 healthy volunteers. To compare MRI and thallium-SPECT, the left ventricle was divided into five segments, and the presence of myocardial infarction was determined in each segment. MRI demonstrated an abnormally bright signal in 49 of 140 segments (five segments each from 23 patients and 5 volunteers); thallium-SPECT showed a fixed perfusion defect in 52 segments, for an 85% diagnostic concordance rate. The size of the myocardial infarction measured on MRI corresponded well to that measured on thallium-SPECT (r = .70, P < .01). Breath-hold turbo spin-echo T2 MRI can be used for detection of acute myocardial infarction in conjunction with thallium-SPECT, especially when accurate localization of lesion, increased spatial resolution, and anatomic landmarks are needed.

PurposeTo assess the efficacy of pregabalin by showing differences in the neuronal activities of fibromyalgia (FM) patients before and after longitudinal treatment using functional magnetic resonance imaging (fMRI).Materials and methodsIn total, 21 female patients with FM and 11 age- and gender-matched healthy controls participated. FM patients underwent fMRI at baseline and following pharmacological therapy with pregabalin to diminish their pain. Pressure-pain stimuli were delivered on the subject's thumbnail bed during fMRI scans. Brain activation regions in fMRI were evaluated for longitudinal changes using a paired t-test. Changes in clinical features were also assessed with the Fibromyalgia Impact Questionnaire (FIQ), Brief Fatigue Inventory (BFI), Beck Depression Inventory (BDI), Widespread Pain Index (WPI), Symptom Severity Scale Score (SSS), and State-Trait Anxiety Inventory (STAI).ResultsClinical scores were reduced significantly following therapy with five of the six clinical tests (FIQ, BFI, BDI, WPI, SSS; p < 0.05). Brain activation post-treatment was significantly lower than that pre-treatment in 13 regions of the brain (p < 0.001).ConclusionsOur findings confirm that pregabalin influences aspects of the whole pain matrix, using fMRI, inducing longitudinal changes in neuronal activity during the pain state, and that it reduces pain and other core symptoms of FM. This method could be applied to other longitudinal clinical trials of pharmacological treatments for FM.

OBJECTIVE The aim of this study is to compare gray matter (GM) volume and white matter (WM) integrity in Apolipoprotein E4 (ApoE e4) carriers with that of ApoE e4 noncarriers using the voxel-based morphometry and diffusion tensor imaging (DTI) to investigate the effect of the ApoE e4 on brain structures in subjective memory impairment (SMI) without white matter hyperintensities (WMH). METHODS Altogether, 26 participants with SMI without WMH were finally recruited from the Memory impairment clinics of Pusan National University Hospital in Korea. All participants were ApoE genotyped (ApoE e4 carriers: n = 13, matched ApoE e4 noncarriers: n = 13) and underwent 3-tesla magnetic resonance imaging (MRI) including 3-dimensional volumetric images for GM volume and DTI for WM integrity. RESULTS ApoE e4 carriers compared with noncarriers in SMI without WMH showed the atrophy of GM in inferior temporal gyrus, inferior parietal lobule, anterior cingulum, middle frontal gyrus, and precentral gyrus and significantly lower fractional anisotropy WM values in the splenium of corpus callosum and anterior corona radiate. CONCLUSION Our findings suggest that the ApoE e4 is associated with both atrophy of GM volume and disruption of WM integrity in SMI without WMH.

Isolated monoparesis of any lower limb caused by acute schemic stroke is uncommon. Among cases of isolated monoaresis, reports of sudden isolated foot drop are rarely reported 1,2]. This symptom, which presents with a peroneal-like distriution, has been shown to be caused by small cortical lesions in he parasagital precentral gyrus. However, to our knowledge, there ave been no reports of isolated foot drop associated with a lesion n the supplementary motor area (SMA). We report a patient with solated foot drop after acute infarction of the SMA.

To assess the capability of gadolinium polylysine-enhanced cardiac magnetic resonance (MR) imaging in depicting normal and ischemic myocardium during occlusion and reperfusion of the left anterior descending artery.Contrast-enhanced MR images were obtained in 18 cats during 90 minutes each of occlusion and reperfusion. The change in signal intensity (SI) was compared among normal myocardium and central and peripheral ischemic zones. Results were compared with those of 2,3,5-triphenyltetrazolium chloride staining.During occlusion, the ischemic zone lacked enhancement while normal myocardium had gradual enhancement. During reperfusion, the ischemic zone had strong enhancement. In cats with large infarction, the central and peripheral ischemic zones had intermediate and high SI, respectively; in cats with focal or no infarction, the entire ischemic zone had high SI.Occlusive and reperfused myocardial infarction can be detected at gadolinium polylysine-enhanced MR imaging by means of differential SI changes in normal myocardium and central and peripheral ischemic zones.

On the basis of the principles of the time-of-flight method and the 3-D angiogram obtained by the 2-D planar image scanning technique using 90° RF pulses with short repetition time, we have obtained a coronary angiogram around the heart including the coronary arteries and veins. The cine NMR imaging technique is also incorporated in synchronizing ECG R waves to reduce the motion artifact and at the same time to induce the saturation effect on the static samples. Images of the large bulk blood flow corresponding to the heart chamber and descending aorta are further removed by postprocessing. The final 3-D angiogram is then formed by stacking the 2-D images and contrast is further enhanced by the maximum ray tracing algorithm. © 1991 Academic Press, Inc.

We have obtained a coronary angiogram around the heart including the coronary arteries and veins based on the principles of the time-of-flight method and 3-D angiogram obtained by the 2-D planar-image scanning technique using 90' RF pulses with short repetition time. ECG-triggered cine NMR imaging technique is also incorporated to reduce the motion artifact and at the same time to induce the saturation effect on the static samples. Images of the large bulk blood flow corresponding to such as the heart chamber and descending aorta are further removed by post processing using thresholding and segmentation. Final 3-D angiogram was then formed by stacking the 2-D images and contrast is further enhanced by the maximum ray axing algorithm.

Magnetic resonance current density imaging (MRCDI) is a useful method for measuring electrical current density distribution inside a subject. Due to the requirement of subject rotations in MRCDI, MRCDI has not been widely applied to in vivo studies. In this paper, we propose a new current density image (CDI) reconstruction method by which a single component of the current density can be imaged by MRCDI without subject rotations. After measuring one of the two magnetic field components, produced by the current density component passing through the measurement plane, we have reconstructed the current density component images in the spatial frequency domain. Even though the proposed method has a limitation that the area of magnetic field measurement should be much larger than that of the current density, the proposed method is expected to expedite MRCDI applications to in vivo studies.

To study the effects of formalin fixation, signal intensity characteristics of the stomach-wall layers, and findings suggestive of cancerous invasion to the stomach wall in vitro with magnetic resonance (MR) imaging in humans.MR images of nine specimens of stomach cancer and 29 normal specimens were obtained at 4.7 T; 26 of the normal specimens were fixed in 10% formalin for 2 hours to 187 days before imaging. The field gradient was 10 G/cm; the spatial resolution, 0.1 mm.The mucosal, submucosal, and proper-muscle layers were clearly identifiable. The submucosa of the fresh specimens had the lowest signal intensity of all specimens on both T1- and T2-weighted images (P.01). No statistical correlation existed between signal intensity and duration of fixation. Tumor invasion was detected in seven of eight specimens with mucosal invasion, all eight specimens with submucosal invasion, and three of six specimens with muscle invasion.In vitro MR imaging enabled differentiation of all three layers of the stomach wall, detection of the cancer, and measurement of the depth of invasion.