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1.  Oxygenation in Cervical Cancer and Normal Uterine Cervix assessed using BOLD MRI at 3 T1 
NMR in biomedicine  2012;25(12):1321-1330.
Hypoxia is reported to be a biomarker for poor prognosis in cervical cancer. However, a practical non-invasive method is needed for routine clinical evaluation of tumor hypoxia. This study examined the potential use of BOLD (Blood Oxygenation Level Dependent) contrast MRI as a non-invasive technique to assess tumor vascular oxygenation at 3 T. Following IRB-approved informed consent and in compliance with HIPAA, successful results were achieved in nine patients with locally advanced cervical cancer (FIGO stage IIA to IVA) and three normal volunteers. In the first four patients, dynamic T2*-weighted MRI was performed in the transaxial plane using a multi-shot EPI sequence while patients breathed room air followed by oxygen (15 dm3/min). Later, a multi-echo gradient echo examination was added to provide quantitative R2* measurements. Baseline T2*-weighted signal intensity was quite stable, but increased to various extents in tumors upon initiation of oxygen breathing. Signal in normal uterus increased significantly, while iliacus muscle did not change. R2* responded significantly in healthy uterus, cervix, and eight cervical tumors. This preliminary study demonstrates that BOLD MRI of cervical cancer at 3 T is feasible. However, more patients must be evaluated and followed clinically before any prognostic value can be determined.
doi:10.1002/nbm.2804
PMCID: PMC3445718  PMID: 22619091
hypoxia; MRI; cervical cancer; BOLD; oxygen
2.  Donepezil effects on hippocampal and prefrontal functional connectivity in Alzheimer’s disease: Preliminary report 
Journal of Alzheimer's disease : JAD  2012;31(0 3):S221-S226.
We used functional connectivity magnetic resonance imaging (fcMRI) to investigate changes in interhemispheric brain connectivity in 11 patients with mild Alzheimer’s disease (AD) following eight weeks of treatment with the cholinesterase inhibitor donepezil. We examined functional connectivity between four homologous temporal, frontal, and occipital regions. These regions were selected to represent sites of AD neuropathology, sites of donepezil-related brain activation change in prior studies, and sites that are minimally affected by the pathologic changes of AD. Based on previous findings of selective, localized frontal responses to donepezil, we predicted that frontal connectivity would be most strongly impacted by treatment. Of the areas we examined, we found that treatment had a significant effect only on functional connectivity between right and left dorsolateral prefrontal cortices. Implications for understanding the impact of donepezil treatment on brain functioning and behavior in patients with AD are discussed. This preliminary report suggests that fcMRI may provide a useful index of treatment outcome in diseases affecting brain connectivity. Future research should investigate these treatment-related changes in larger samples of patients and age-matched controls.
doi:10.3233/JAD-2012-120709
PMCID: PMC3749074  PMID: 22886013
Alzheimer’s disease; donepezil; functional connectivity; dorsolateral prefrontal cortex; hippocampus
3.  Regionally Selective Atrophy after Traumatic Axonal Injury 
Archives of neurology  2010;67(11):1336-1344.
Objectives
To determine the spatial distribution of cortical and subcortical volume loss in patients with diffuse traumatic axonal injury and to assess the relationship between regional atrophy and functional outcome.
Design
Prospective imaging study. Longitudinal changes in global and regional brain volumes were assessed using high-resolution magnetic resonance imaging (MRI)-based morphometric analysis.
Setting
Inpatient traumatic brain injury unit
Patients or Other Participants
Twenty-five patients with diffuse traumatic axonal injury and 22 age- and sex-matched controls.
Main Outcome Measure
Changes in global and regional brain volumes between initial and follow-up MRI were used to assess the spatial distribution of post-traumatic volume loss. The Glasgow Outcome Scale – Extended was the primary measure of functional outcome.
Results
Patients underwent substantial global atrophy with mean brain parenchymal volume loss of 4.5% (95% Confidence Interval: 2.7 – 6.3%). Decreases in volume (at a false discovery rate of 0.05) were seen in several brain regions including the amygdala, hippocampus, thalamus, corpus callosum, putamen, precuneus, postcentral gyrus, paracentral lobule, and parietal and frontal cortices, while other regions such as the caudate and inferior temporal cortex were relatively resistant to atrophy. Loss of whole brain parenchymal volume was predictive of long-term disability, as was atrophy of particular brain regions including the inferior parietal cortex, pars orbitalis, pericalcarine cortex, and supramarginal gyrus.
Conclusion
Traumatic axonal injury leads to substantial post-traumatic atrophy that is regionally selective rather than diffuse, and volume loss in certain regions may have prognostic value for functional recovery.
doi:10.1001/archneurol.2010.149
PMCID: PMC3465162  PMID: 20625067
4.  Effects of Lamotrigine on Hippocampal Activation in Corticosteroid-Treated Patients 
Journal of affective disorders  2010;126(3):415-419.
Background
An extensive animal literature suggests that stress or excessive corticosteroid exposure is associated with changes in hippocampal function and memory. These findings are pertinent to psychiatric disorders with elevated cortisol, Cushing’s disease and the millions of patients receiving prescription corticosteroids. In animals, agents that decrease glutamate release attenuate the effects of corticosteroids on the hippocampus. Minimal data are available on preventing or reversing the effects of corticosteroids on the human hippocampus. We previously reported improvement in memory in corticosteroid-treated patients given lamotrigine. In this report, we examined the impact of lamotrigine on task-related hippocampal activation in patients taking prescription corticosteroids.
Methods
A total of 28 outpatients taking long-term oral prednisone for medical conditions, such as renal transplant rejection, were randomized to lamotrigine or placebo for 24 weeks. Hippocampal activation in response to a visual memory task was assessed with blood oxygenation level dependent (BOLD) functional magnetic resonance imaging (fMRI).
Results
Consistent with a reduction in glutamate release, the right posterior hippocampus showed a significant decrease in task-related activation in the lamotrigine group as compared to the placebo group.
Limitations
The modest sample size and an assessment period of only 24 weeks are study limitations.
Conclusions
Between-group differences in hippocampal activation were observed. The results suggest that an agent that modulates glutamate may modify the effects of long-term corticosteroid exposure on the human hippocampus.
doi:10.1016/j.jad.2010.04.010
PMCID: PMC2947572  PMID: 20580827
functional magnetic resonance imaging; lamotrigine; prednisone; hippocampus
5.  Diffusion Tensor Imaging Biomarkers for Traumatic Axonal Injury: Analysis of Three Analytic Methods 
Traumatic axonal injury (TAI) is a common mechanism of traumatic brain injury not readily identified using conventional neuroimaging modalities. Novel imaging modalities such as diffusion tensor imaging (DTI) can detect microstructural compromise in white matter (WM) in various clinical populations including TAI. DTI-derived data can be analyzed using global methods (i.e., WM histogram or voxel based approaches) or a regional approach (i.e., tractography). While each of these methods produce qualitatively comparable results, it is not clear which is most useful in clinical research and ultimately in clinical practice. This study compared three methods of analyzing DTI-derived data with regard to detection of WM injury and their association with clinical outcomes. Thirty patients with TAI and 19 demographically similar normal controls were scanned using a 3T magnet. Patients were scanned approximately eight months post-injury, and underwent an outcomes assessment at that time. Histogram analysis of FA and MD showed global WM integrity differences between patients and controls. Voxel-based and tractography analyses showed significant decreases in FA within centroaxial structures involved in TAI. All three techniques were associated with functional and cognitive outcomes. DTI measures of microstructural integrity appear robust, as the three analysis techniques studied showed adequate utility for detecting WM injury.
doi:10.1017/S1355617710001189
PMCID: PMC3097093  PMID: 21070694
DTI; DAI; Traumatic Brain Injury; memory; Tractography; cognitive outcomes
6.  Cerebral Atrophy after Traumatic White Matter Injury: Correlation with Acute Neuroimaging and Outcome 
Journal of Neurotrauma  2008;25(12):1433-1440.
Abstract
Traumatic brain injury (TBI) is a pathologically heterogeneous disease, including injury to both neuronal cell bodies and axonal processes. Global atrophy of both gray and white matter is common after TBI. This study was designed to determine the relationship between neuroimaging markers of acute diffuse axonal injury (DAI) and cerebral atrophy months later. We performed high-resolution magnetic resonance imaging (MRI) at 3 Tesla (T) in 20 patients who suffered non-penetrating TBI, during the acute (within 1 month after the injury) and chronic stage (at least 6 months after the injury). Volume of abnormal fluid-attenuated inversion-recovery (FLAIR) signal seen in white matter in both acute and follow-up scans was quantified. White and gray matter volumes were also quantified. Functional outcome was measured using the Functional Status Examination (FSE) at the time of the chronic scan. Change in brain volumes, including whole brain volume (WBV), white matter volume (WMV), and gray matter volume (GMV), correlates significantly with acute DAI volume (r = −0.69, −0.59, −0.58, respectively; p < 0.01 for all). Volume of acute FLAIR hyperintensities correlates with volume of decreased FLAIR signal in the follow-up scans (r = −0.86, p < 0.001). FSE performance correlates with acute hyperintensity volume and chronic cerebral atrophy (r = 0.53, p = 0.02; r = −0.45, p = 0.03, respectively). Acute axonal lesions measured by FLAIR imaging are strongly predictive of post-traumatic cerebral atrophy. Our findings suggest that axonal pathology measured as white matter lesions following TBI can be identified using MRI, and may be a useful measure for DAI-directed therapies.
doi:10.1089/neu.2008.0683
PMCID: PMC2858299  PMID: 19072588
MR imaging; post-traumatic atrophy; TBI

Results 1-6 (6)