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1.

ABSTRACT

BACKGROUND/PURPOSE

To assess correlation between brain lesions and clinical status with 1.5T and 3T magnetic resonance imaging (MRI).

METHODS

Brain MRI fluid‐attenuated inversion‐recovery (FLAIR) sequences were performed in 32 multiple sclerosis (MS) patients. Expanded Disability Status Scale (EDSS) score (mean ± standard deviation) was 2 ± 2.0 (range 0‐8), disease duration 9.3 ± 8.0 (range .8‐29) years.

RESULTS

FLAIR lesion volume (FLLV) at 3T was higher than at 1.5T (P= .01). Correlation between 1.5T FLLV and EDSS score was poor, while 3T FLLV correlated moderately and significantly (rs= .39, P= .03). When controlling for age and depression, correlations between FLLV and cognitive measures were significant at 1.5T for the Judgment of Line Orientation test (JLO) (rs=−.44, P= .05), the Symbol Digit Modalities Test (SDMT) (rs=−.49, P= .02), and the California Verbal Learning Test Delayed Free Recall (CVLT DR) (rs=−.44, P= .04). Correlations at 3T were also significant for these tests, but of greater magnitude: JLO (rs=−.70, P= .0005), SDMT (rs=−.73, P= .0001), CVLT DR (rs=−.061, P= .003). Additional significant correlations obtained only at 3T included the 2 second‐paced auditory serial addition test (rs=−.55, P= .01), the Brief Visuospatial Memory Test‐Delayed Free Recall (rs=−.56, P= .007), and the California Verbal Learning Test Total Recall (rs=−.42, P= .05).

CONCLUSION

MRI at 3T may boost sensitivity and improve validity in MS brain lesion assessment.
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2.

Background:

Approximately 10% of patients clinically diagnosed with early Parkinson's disease (PD) subsequently have normal dopaminergic functional imaging. Transcranial sonography (TCS) has been shown to detect midbrain hyperechogenicity in approximately 90% of Parkinson's disease (PD) patients and 10% of the healthy population. The aim of this study was to investigate the prevalence of midbrain hyperechogenicity in patients with suspected parkinsonism and scans without evidence of dopaminergic deficit (SWEDD), in comparison to PD patients.

Methods:

TCS was performed in 14 patients with SWEDD and 19 PD patients.

Results:

There was a significantly increased area of echogenicity in the PD group (0.24 ± 0.06 cm2), compared to the group of patients with SWEDD (0.13 ± 0.06 cm2; P < 0.001). One (9.1%) of these patients, compared to 14 (82.5%) of the PD patients, was found to have hyperechogenicity (P < 0.001).

Conclusions:

We conclude that TCS is useful to distinguish PD patients from patients with suspected parkinsonism and SWEDD. © 2012 Movement Disorder Society
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3.

ABSTRACT

BACKGROUND AND PURPOSE

Features of tumefactive demyelinating lesion (TDL) on magnetic resonance imaging (MRI) can facilitate the differential diagnosis of TDL and neoplastic lesions, but vary considerably among patients. The larger TDL grows, the more difficult it becomes to differentiate TDL from neoplastic lesions. The purpose of this study was to elucidate typical MRI features in 12 patients with large TDL (>30 mm in diameter).

METHODS

We identified 12 patients with large TDL (six men, six women; age range 17‐64 years, median age 27 years) and studied the clinical histories and the results of laboratory and various radiological studies in these patients. All cases of clinically definite multiple sclerosis were diagnosed in accordance with McDonald's revised criteria.

RESULTS

Common MRI features of large TDLs included variable degrees of mass effect (71%) and edema (100%), a T2 hypointense rim (79%), venular enhancement (57%), and peripheral restriction on diffusion‐weighted images (50%). Ring enhancement (38%), open‐ring enhancement (31%), or decreased N‐acetylaspartate ratios on magnetic resonance spectroscopy (22%) were less frequently observed. Brain angiography demonstrated venous dilatations on and around the TDL.

CONCLUSIONS

The diagnosis of large TDL is challenging. Our findings suggest that multiple venous dilatations on and around TDLs on angiography can facilitate diagnosis.
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4.

ABSTRACT

BACKGROUNDS AND PURPOSE

The aim of this study is to develop a near‐infrared spectroscopy (NIRS)‐based system that recognizes pleasant and unpleasant human emotions based on cerebral blood flow (CBF) in order to understand the minds of patients whose brain function is severely impaired. The forehead region is easily accessible to NIRS measurements, whereas the role of the anterior prefrontal cortex (PFC) in the processing of emotion remains to be elucidated.

METHODS

Initially, using event‐related NIRS we examined changes in oxygenated hemoglobin (oxy‐Hb) as an indicator of regional CBF changes, which reflect brain activity directly related to emotions, but not to cognitive operations in the anterior frontal regions, during viewing affective pictures. The event‐related potentials (ERPs), systemic blood pressure, and pulse rate were also measured simultaneously.

RESULTS

The event‐related analysis of changes in oxy‐Hb for a 6 s‐picture presentation period showed that very unpleasant emotion was accompanied by an increase in oxy‐Hb in the bilateral ventrolateral PFCs, while very pleasant emotion was accompanied by a decrease in oxy‐Hb in the left dorsolateral PFC. There were no significant differences in either ERPs or autonomic nervous system activities between the two emotional states.

CONCLUSION

These findings suggest the possibility of recognizing patients’ emotions from CBF changes.
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5.

Objective

Based on new understanding of nondopaminergic pathways involved in Parkinson's disease (PD) pathophysiology, a selective adenosine A2A receptor antagonist, istradefylline, shows promise for the treatment of PD.

Methods

Istradefylline (40mg/day) was studied in levodopa‐treated PD subjects experiencing prominent wearing‐off motor fluctuations. At 23 North American sites, 196 subjects were randomized in a double‐blind, 12‐week outpatient clinical trial of istradefylline (114 completing the trial) or placebo (58 completing the trial). The primary efficacy measure was change from baseline to end point in the percentage of daily awake “off” time, recorded by subjects using a patient PD diary. Secondary end points evaluated “on” time (including “on time with dyskinesia”), the Unified Parkinson's Disease Rating Scale, and a Clinical Global Impression–Improvement of Illness score. Clinical laboratory, electrocardiograms, vital signs, and adverse event monitoring comprised the safety monitoring.

Results

After randomization, approximately 88% of subjects completed the double‐blind period. Compared with baseline, the decrease of daily awake “off” time for istradefylline was a mean (± standard deviation) of ?10.8 ± 16.6% (95% confidence interval, ?13.46 to ?7.52) and for placebo, ?4.0 ± 15.7% (95% confidence interval, ?7.73–0.31; p = 0.007 using two‐way analysis of variance). This effect corresponded to changes from baseline in total daily awake “off” time of ?1.8 ± 2.8 hours for istradefylline and ?0.6 ± 2.7 hours for placebo (p = 0.005). Treatment‐emergent adverse effects with istradefylline were generally mild.

Interpretation

Istradefylline was safe, well tolerated, and offered a clinically meaningful reduction in “off” time without increased troublesome dyskinesia. Ann Neurol 2008
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6.

Aim

Despite continuing research into Alzheimer's disease (AD), its pathological mechanisms and modulating factors remain unknown. Several genes influence AD pathogenesis by affecting inflammatory pathways. Myocyte‐enhancer factor 2C (MEF2C) is one such candidate gene for AD.

Methods

We examined MEF2C mRNA expression levels and methylation rates of CpG on its promoter region in peripheral leukocytes from Japanese AD patients compared with age‐ and sex‐matched control subjects.

Results

In peripheral leukocytes, MEF2C mRNA expression levels in AD subjects were significantly lower than those in control subjects (0.86 ± 0.25 vs 0.99 ± 0.27, respectively, P = 0.007) and were correlated with the Alzheimer's Disease Assessment Scale (r = ?0.345, P = 0.049) and the Mini Mental State Examination (r = 0.324, P = 0.02). No significant differences were found in methylation rates between AD and control subjects.

Conclusion

MEF2C mRNA expression in leukocytes may be a biological marker for cognitive decline in AD.
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7.

Objective

To review evidence regarding the prevalence, causation, clinical implications, aspects of healthcare utilisation and management of depression and anxiety in chronic heart failure and chronic obstructive pulmonary disease.

Design

A critical review of the literature (1994–2009).

Findings

The prevalence of depression and anxiety is high in both chronic obstructive pulmonary disease (8–80% depression; 6–74% anxiety) and chronic heart failure (10–60% depression; 11–45% anxiety). However, methodological weaknesses and the use of a wide range of diagnostic tools make it difficult to reach a consensus on rates of prevalence. Co‐morbid depression and anxiety are associated with increased mortality and healthcare utilisation and impact upon functional disability and quality of life. Despite these negative consequences, the identification and management of co‐morbid depression and anxiety in these two diseases is inadequate. There is some evidence for the positive role of pulmonary/cardiac rehabilitation and psychotherapy in the management of co‐morbid depression and anxiety, however, this is insufficient to guide recommendations.

Conclusions

The high prevalence and associated increase in morbidity and mortality justifies future research regarding the management of anxiety and depression in both chronic heart failure and chronic obstructive pulmonary disease. Current evidence suggests that multi‐faceted interventions such as pulmonary and cardiac rehabilitation may offer the best hope for improving outcomes for depression and anxiety. Copyright © 2009 John Wiley & Sons, Ltd.
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8.

Background:

Histopathological studies and animal models suggest that hippocampal subfields may be differently affected by aging, Alzheimer's disease (AD), and other diseases. High‐resolution images at 4 Tesla depict details of the internal structure of the hippocampus allowing for in vivo volumetry of different subfields. The aims of this study were as follows: (1) to determine patterns of volume loss in hippocampal subfields in normal aging, AD, and amnestic mild cognitive impairment (MCI). (2) To determine if measurements of hippocampal subfields provide advantages over total hippocampal volume for differentiation between groups.

Methods:

Ninety‐one subjects (53 controls (mean age: 69.3 ± 7.3), 20 MCI (mean age: 73.6 ± 7.1), and 18 AD (mean age: 69.1 ± 9.5) were studied with a high‐resolution T2 weighted imaging sequence aimed at the hippocampus. Entorhinal cortex (ERC), subiculum, CA1, CA1‐CA2 transition zone (CA1‐2), CA3 & dentate gyrus (CA3&DG) were manually marked in the anterior third of the hippocampal body. Hippocampal volume was obtained from the Freesurfer and manually edited.

Results:

Compared to controls, AD had smaller volumes of ERC, subiculum, CA1, CA1‐2, and total hippocampal volumes. MCI had smaller CA1‐2 volumes. Discriminant analysis and power analysis showed that CA1‐2 was superior to total hippocampal volume for distinction between controls and MCI.

Conclusion:

The patterns of subfield atrophy in AD and MCI were consistent with patterns of neuronal cell loss/reduced synaptic density described by histopathology. These preliminary findings suggest that hippocampal subfield volumetry might be a better measure for diagnosis of early AD and for detection of other disease effects than measurement of total hippocampus. Hum Brain Mapp, 2010. © 2010 Wiley‐Liss, Inc.
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9.

Objectives:

Writer's cramp (WC) is characterized by excessive cocontractions of agonist and antagonist hand and forearm muscles during writing. Changes in functional magnetic resonance imaging activation patterns in such conditions can be ambiguous as they might either reflect some aspect of the primary pathophysiological mechanism or, alternatively, may be the result of adaptive actions during task execution. To circumvent this problem, we examined WC patients during rest, i.e., without a task, using independent component analysis (ICA) applied to the blood oxygen level‐dependent time series.

Methods:

Functionally connected brain networks during rest were defined by ICA to assess differences between WC patients (n = 16) and healthy controls (n = 16). Analysis was carried out using FMRIB's Software Library.

Results:

Two functional networks showed between‐group differences, the sensorimotor network and the default‐mode network. In WC patients, the connectivity was reduced in the left postcentral area and increased in basal ganglia in contrast to healthy controls. These changes were not reversed after treatment with botulinum toxin.

Conclusions:

In line with other studies, the results show a dysfunction in cortico‐subcortical circuits in WC involving somatosensory cortex, areas interfacing the sensory and motor systems, and putamen contralateral to symptomatic hand. Hum Brain Mapp, 2012. © 2011 Wiley Periodicals, Inc.
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10.

ABSTRACT

BACKGROUND

In the treatment of acute ischemic stroke, intravenous (IV) recombinant tissue plasminogen (rt‐PA) and intraarterial (IA) interventions are often combined. However, the optimal dose of IV rt‐PA preceding endovascular treatment has not been established.

METHODS

Studies that used combined IV and IA thrombolysis were identified from a search of the MEDLINE, PubMed, and Cochrane databases. We compared the rates of angiographic recanalization, symptomatic intracerebral hemorrhage (sICH), and favorable functional outcome between patients who had been treated with .6 mg/kg IV rt‐PA and those who had received .9 mg/kg rt‐PA.

RESULTS

Eleven studies met our criteria. In 7 studies, .6 mg/kg IV rt‐PA had been administered to 317 patients, whereas 140 patients in 4 studies had received .9 mg/kg of IV rt‐PA. The weighted mean of median National Institutes of Health Stroke Scale score at presentation was 18.3 in the .6 mg/kg group (median range 9‐34), and 17.3 in the .9 mg/kg group (median range 4‐39). Patients in the .9 mg/kg group had higher rates of favorable outcome [odds ratio (OR) = 1.60, 95% confidence interval (CI) = (1.07‐2.40), P= .022] and similar rates of sICH [OR = .86 (95% CI .41‐1.83), P= .70]. Depending on the statistics used, the higher angiographic recanalization rate among patients treated with .9 mg/kg was significant (P= .03, events/trial syntax logistic regression) or borderline significant (P= .07, random effects model).

CONCLUSION

Our analysis suggests that using .9 mg/kg IV rt‐PA prior to IA thrombolysis is safe and may be associated with higher recanalization rates and better functional outcome at 3 months.
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11.

Objectives:

Brisk walking, a sensitive test to evaluate gait capacity in normal and pathological aging such as parkinsonism, is used as an alternative to classical fitness program for motor rehabilitation and may help to decrease the risk of cognitive deterioration observed with aging. In this study, we aimed to identify brain areas normally involved in its control.

Methods:

We conducted a block‐design blood oxygen level dependent function magnetic resonance imaging (BOLD fMRI) experiment in 18 young healthy individuals trained to imagine themselves in three main situations: brisk walking in a 25‐m‐long corridor, standing or lying. Imagined walking time (IWT) was measured as a control of behavioral performance during fMRI.

Results:

The group mean IWT was not significantly different from the actual walking time measured during a training session prior to the fMRI study. Compared with other experimental conditions, mental imagery (MI) of brisk walking was associated with stronger activity in frontal and parietal regions mainly on the right, and cerebellar hemispheres, mainly on the left. Presumed imagined walking speed (2.3 ± 0.4 m/s) was positively correlated with activity levels in the right dorsolateral prefrontal cortex and posterior parietal lobule along with the vermis and the left cerebellar hemisphere.

Interpretations:

A new finding in this study is that MI of brisk walking in young healthy individuals strongly involves processes lateralized in right fronto‐parietal regions along with left cerebellum. These results show that brisk walking might be a non automatic locomotor activity requiring a high‐level supraspinal control. Hum Brain Mapp, 2012. © 2011 Wiley Periodicals, Inc.
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12.

ABSTRACT

BACKGROUND AND PURPOSE

Some patients with posterior reversible encephalopathy syndrome (PRES) present with atypical clinical and neuroimaging findings. The purpose of this study is to review the clinical and neuroimaging findings in patients diagnosed with PRES.

METHODS

We retrospectively included all patients diagnosed with PRES between January 2005 and March 2009. We reviewed demographic, clinical and laboratory data, neuroimaging findings, and prognosis.

RESULTS

Twenty‐four patients were included with a median age of 19 years. The clinical presentations included seizures (91.7%), headache (83.3%), visual disturbance (62.5%), encephalophathy (29.2%), and paralysis (8.3%). Co‐morbidities included systemic lupus erythematous (29.2%), kidney disease (20.8%), eclampsia (20.8%), renal artery stenosis (12.5%), Takayasu arteritis (4.2%), Sheehan's syndrome (4.2%), allergic purpura (4.2%), and acute intermittent porphyria (4.2%). Acute elevation of blood pressure was found in 22 patients (91.7%). Ten patients (41.7%) used steroids or immunosuppressants, three (12.5%) had acute renal failure before the symptoms. Atypical neuroimaging features included involvement of the frontal lobe (54.2%), basal ganglia (4.2%) or cortex (8.3%), and irreversible lesions (3/18, 16.7%).

CONCLUSIONS

A large proportion of patients with PRES may present with atypical neuroimaging findings. Apart from the known risk factors, such as hypertension, immunosuppressants, and renal failure of various etiologies may be the precipitants of PRES.
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13.

Objective

To determine whether amyloid deposition is associated with impaired neuropsychological (NP) performance and whether cognitive reserve (CR) modifies this association.

Methods

In 66 normal elderly controls and 17 patients with Alzheimer disease (AD), we related brain retention of Pittsburgh Compound B (PiB) to NP performance and evaluated the impact of CR using education and American National Adult Reading Test intelligence quotient as proposed proxies.

Results

We found in the combined sample of subjects that PiB retention in the precuneus was inversely related to NP performance, especially in tests of memory function, but also in tests of working memory, semantic processing, language, and visuospatial perception. CR significantly modified the relationship, such that at progressively higher levels of CR, increased amyloid deposition was less or not at all associated with poorer neuropsychological performance. In a subsample of normal controls, both the main effect of amyloid deposition of worse memory performance and the interaction with CR were replicated using a particularly challenging memory test.

Interpretation

Amyloid deposition is associated with lower cognitive performance both in AD patients and in the normal elderly, but the association is modified by CR, suggesting that CR may be protective against amyloid‐related cognitive impairment. ANN NEUROL 2010;67:353–364
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14.

Objective

Delayed ischemic neurological deficit (DIND) contributes to poor outcome in subarachnoid hemorrhage (SAH) patients. Because there is continuing uncertainty as to whether proximal cerebral artery vasospasm is the only cause of DIND, other processes should be considered. A potential candidate is cortical spreading depolarization (CSD)‐induced hypoxia. We hypothesized that recurrent CSDs influence cortical oxygen availability.

Methods

Centers in the Cooperative Study of Brain Injury Depolarizations (COSBID) recruited 9 patients with severe SAH, who underwent open neurosurgery. We used simultaneous, colocalized recordings of electrocorticography and tissue oxygen pressure (ptiO2) in human cerebral cortex. We screened for delayed cortical infarcts by using sequential brain imaging and investigated cerebral vasospasm by angiography or time‐of‐flight magnetic resonance imaging.

Results

In a total recording time of 850 hours, 120 CSDs were found in 8 of 9 patients. Fifty‐five CSDs (∼46%) were found in only 2 of 9 patients, who later developed DIND. Eighty‐nine (∼75%) of all CSDs occurred between the 5th and 7th day after SAH, and 96 (80%) arose within temporal clusters of recurrent CSD. Clusters of CSD occurred simultaneously, with mainly biphasic CSD‐associated ptiO2 responses comprising a primary hypoxic and a secondary hyperoxic phase. The frequency of CSD correlated positively with the duration of the hypoxic phase and negatively with that of the hyperoxic phase. Hypoxic phases significantly increased stepwise within CSD clusters; particularly in DIND patients, biphasic ptiO2 responses changed to monophasic ptiO2 decreases within these clusters. Monophasic hypoxic ptiO2 responses to CSD were found predominantly in DIND patients.

Interpretation

We attribute these clinical ptiO2 findings mainly to changes in local blood flow in the cortical microcirculation but also to augmented metabolism. Besides classical contributors like proximal cerebral vasospasm, CSD clusters may reduce O2 supply and increase O2 consumption, and thereby promote DIND. ANN NEUROL 2010;67:607–617
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15.

Aim

To increase research rigour and create a plausible way to assess clinical effectiveness, it is necessary to measure the degree to which interventions are delivered as intended (fidelity). Generic fidelity measures enable evaluation of more than one intervention through observation of unique and general characteristics relevant across interventions. This study describes the first generic fidelity measure in paediatrics.

Method

Items were constructed from multiple sources to create a general attributes domain and two paediatric cerebral palsy (CP) intervention‐specific domains. After a pre‐testing procedure, raters were trained and videos of clinical interventions were rated to test the measure's psychometric properties.

Results

The Paediatric Rehabilitation Observational measure of Fidelity (PROF) consisted of 30 items. Six raters were trained on the PROF and rated 25 videos. Internal consistency (α) and interrater reliability (IRR) for the frequency scale showed the following results: context therapy: α=0.71, IRR=0.75; child therapy: α=0.85, IRR=0.87; and general attributes; α=0.78, IRR=0.82. Quality scale scores across domains demonstrated internal consistency greater than 0.80 and interrater reliability of less than 0.40. Pearson's correlations (r=?0.71, p<0.001) and analyses of variance (p=0.01) validated that each intervention domain was an independent construct.

Interpretation

The PROF is reliable and valid for evaluating interventions used for children with CP. Future studies may use the measure's framework, general attributes domain, and procedures to test the psychometric properties of other interventions.
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16.

Objective:

The underlying hypothesis of our work is that specific clinical neuropsychiatric benefits can be achieved by selective activation of specific axonal pathways during deep brain stimulation (DBS). As such, the goal of this study was to develop a method for identifying axonal pathways whose activation is most likely necessary for achieving therapeutic benefits during DBS.

Experimental design:

Our approach combined clinical data, diffusion tensor tractography, and computer models of patient‐specific neurostimulation to identify particular axonal pathways activated by DBS and determine their correlations with individual clinical outcome measures. We used this method to evaluate a cohort of seven treatment‐resistant depression patients treated with DBS of the ventral anterior internal capsule and ventral striatum (VC/VS).

Principal observations:

Clinical responders exhibited five axonal pathways that were consistently activated by DBS. All five pathways coursed lateral and medial to the VS or dorsal and lateral to the nucleus accumbens; however, details of their specific trajectories differed. Similarly, one common pathway was identified across nonresponders.

Conclusions:

Our method and preliminary results provide important background for studies aiming to expand scientific characterization of neural circuitry associated with specific psychiatric outcomes from DBS. Furthermore, identification of pathways linked to therapeutic benefit provides opportunities to improve clinical selection of surgical targets and stimulation settings for DBS devices. Hum Brain Mapp, 2012. © 2011 Wiley Periodicals, Inc.
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17.

Objectives

It is well‐known that in cross‐sectional analyses, agreement between informants is modest as best when rating attention‐deficit/hyperactivity disorder and other disruptive behaviour disorder symptoms. We here aimed to develop recommendations for the use of multi‐informant data in the context of longitudinal developmental analyses that examine symptom trajectories over time.

Method

Using parallel process modelling, we estimated parent–teacher agreement in inattention and hyperactivity/impulsivity symptom initial levels and slopes across the elementary school years (ages 7, 9, and 11) for a community sample of n = 1,388 youth. We also used these models to examine whether initial levels and slopes differed significantly across informants.

Results

Informant agreement was low to moderate and higher for inattention slopes (r = .47) than for hyperactivity/impulsivity slopes (r = .23). Parents and teachers reported opposite developmental trends for inattention with teachers reporting declines and parents reporting increases over time. Parents reported overall higher levels of hyperactivity/impulsivity, but there were no average informant differences in slopes.

Conclusion

Of the options available, we recommend specifying separate but correlated factors for different informants in developmental analyses of attention‐deficit/hyperactivity disorder. This can be achieved within latent growth curve and growth mixture models.
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18.

Objectives

To evaluate the presence of chronic cerebrospinal venous insufficiency (CCSVI) and cerebral venous anomalies in a consecutive series of patients with multiple sclerosis (MS), other neurologic diseases (NEU) and healthy controls (HC).

Methods

A consecutive series of 80 MS patients, 41 HC and 26 NEU cases underwent a transcranial and extracranial echo-color Doppler (ECD) evaluation of cerebrospinal venous return in a sonographer-blinded fashion. According to the original Dr. Zamboni's protocol, CCSVI was diagnosed in presence of ≥2 ECD venous criteria.

Results

We did not observe any association between CCSVI and MS. CCSVI was detected in 17.5% of MS cases, 7.3% of HC and 11.5% of NEU patients (p = 0.333). The prevalence of internal jugular vein stenosis (IJV) and the proportion of patients with any positive ECD criterion differed significantly among groups, being higher in MS cases versus HC (67.5% and 76.2% versus 48.8% and 41.5%, respectively; p = 0.005 and p = 0.006). No relationship between CCSVI and MS type and severity was evidenced.

Conclusions

The present study argues against a positive link between CCSVI and MS risk or severity. Interestingly, a weak association between venous ECD anomalies (in particular IJV stenosis) and MS was observed in our population. This finding should be interpreted with caution due to the possible confounders and needs to be confirmed in large controlled studies.  相似文献   

19.

Objectives:

Magnetic resonance (MRI) studies rely on sulcal boundaries to delineate the human entorhinal cortex (EC) and typically show that EC size is reduced in Alzheimer's disease (AD) and a predictor of future dementia. However, it is unknown if variations in the EC sulcal patterns are associated with AD. We classified the lateral EC sulcal boundary as either a rhinal or collateral pattern and tested the hypotheses that the rhinal pattern was (1) more common in AD and (2) associated with a smaller EC size.

Experimental Design:

MRI was used to determine the prevalence of the rhinal and collateral EC patterns in 421 subjects (212 AD, 107 old normal (ONL), and 102 young NL (YNL). Anatomical validation studies of normal subjects were conducted at postmortem in 34 brain hemispheres and in vivo with 21 MRI volume studies. EC pattern reliability was studied with MRI in both cross‐sectional and longitudinal designs.

Principal Observations:

The rhinal pattern was more frequent in the right hemisphere in AD (47%) compared with ONL (28%, odds ratio = 2.25, P = 0.001). EC pattern was not related to ApoE genotype. The validations showed that the EC sulcal pattern was not associated with the neuronal number, surface area, or volume of the EC. In patients with antemortem MRI studied at postmortem it was equivalently determined, that EC patterns are reliably determined on MRI and do not change with the progressive atrophy of AD.

Conclusions:

The data indicate that the right hemisphere rhinal pattern is over represented in AD as compared with control. However, in normal subjects the EC rhinal pattern is not associated with a diminished EC tissue size. It remains to be demonstrated if the right EC rhinal sulcus pattern association with AD reflects genetic or developmental influences. Hum Brain Mapp, 2009. © 2008 Wiley‐Liss, Inc.
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20.

Purpose:

Head motion during functional MRI scanning can lead to signal artifact, a problem often more severe with children. However, the documentation for the characteristics of head motion in children during various language functional tasks is very limited in the current literature. This report characterizes head motion in children during fMRI as a function of age, sex, and task.

Methods:

Head motion during four different fMRI language tasks was investigated in a group of 323 healthy children between the age of 5 and 18 years. A repeated measures ANOVA analysis was used to study the impact of age, sex, task, and the interaction of these factors on the motion.

Results:

Pediatric subjects demonstrated significantly different amounts of head motion during fMRI when different language tasks were used. Word‐Picture Matching, the only task that involved visual engagement, suffered the least amount of motion, which was significantly less than in any of the other three tasks; the latter were not significantly different from each other. Further examination revealed that the main effect of language task on motion was significantly affected by age, sex, and their interaction.

Conclusion:

Our results suggest that age, sex, and task are all associated with the degree of head motion in children during fMRI experiments. Investigators working with pediatric patients may increase their success by using task components associated with less motion (e.g., visual stimuli), or by using this large scale dataset to estimate the effects of sex and age on motion for planning purposes. Hum Brain Mapp 2009. © 2008 Wiley‐Liss, Inc.
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