Clinical Applications of 7T Including Neurodegenerative Diseases
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Thursday May 12th
Room 710B  10:30 - 12:30 Moderators: Oliver Speck and Kamil Ugurbil

10:30 581-2.   Introduction
Mark E. Ladd
10:54 583.   Higher GABA Concentrations in the Brainstem in Parkinson's Disease by 1H MRS at 7T 
Uzay Emrah Emir1, Susan Rolandelli1, Paul Joseph Tuite1, and Gulin Oz1
1University of Minnesota, Minneapolis, MN, United States

Measuring neurochemical alterations in affected mid-brain structures substantia nigra (SN) and putamen in Parkinson's disease (PD) by 1H MRS has been challenging. Because recent pathological findings indicated earlier involvement of more caudal brainstem regions in PD before the nigrostriatal system, we measured neurochemical profiles of the pons, as well as the SN and putamen, in early-moderate PD by 7T 1H MRS. GABA concentration was higher in the pons (p<0.001) and putamen (p = 0.06) in PD patients (N=11) compared to age-matched healthy controls (N=8). Further research will help determine how these changes relate to disease pathogenesis and pathophysiology.

11:06 584.   MR Relaxometry in PKAN Patients at 1.5T, 3T and 7T 
Monika Dezortova1, Vit Herynek1, Martin Krssak2, Claudia Kronnerwetter3, and Milan Hajek1
1MR-Unit, Dept Diagnostic and Interventional Radiology, Institute for Clinical and Experimental Medicine, Prague, Czech Republic, 2Center for Medical Physics and Biomedical Engineering & MR Centre of Excellence, Medical University of Vienna, Vienna, Austria, 3Dept Radiology & MR Centre of Excellence, Medical University of Vienna, Vienna, Austria

Panthotenate-kinase associated neurodegeneration is characterized by iron accumulation in the basal ganglia. Iron deposits were studied using T2 MR relaxometry at 1.5T, 3T and 7T in three patients and five controls. T2 values of patients decreased significantly in the globus pallidus, increased in the putamen and nucleus caudate, and did not differ in the thalamus and white matter; the iron concentrations in the globus pallidus calculated for B0=1.5T were approximately twice as high as in controls. Measurements at different magnetic fields suggest different ferritin loads in the basal ganglia in patients. However, the presence of other metalloproteins cannot be excluded.

11:18 585.   Susceptibility Mapping of the Substantia Nigra in Parkinson patients at 7 T after one year of diagnosis and treatment 
Andreas Schäfer1, Derek V Ott2, Almut Focke2, Johannes Schwarz2, David Weise2, Robert Turner1, and Sonja A Kotz1
1Max-Planck-Institute for Human Cognitive and Brain Sciences, Leipzig, Germany, 2University Hospital, Leipzig, Germany

Pathological studies have shown that the iron content in the Substantia Nigra is increased in Parkinson patients. It has been shown that susceptibility mapping may indicate a higher iron concentration of the SN in vivo in clinically diagnosed but not medicated PD patients compared to young healthy volunteers. Here we present results of a continuing study by calculating the susceptibility of the SN of an age-matched control group, and also comparing the susceptibility values of the patients after one year of diagnosis and treatment.

11:30 586.   Susceptibility Mapping of Alzheimer Plaques at 7T  -permission withheld
Michael Zeineh1, Hagen Kitzler2, Scott Atlas1, Hannes Vogel3, and Brian Rutt1
1Radiology, Stanford University, Stanford, CA, United States, 2Neuroradiology, 2Department of Neuroradiology, Technische Universitaet Dresden, Germany, 3Pathology, Stanford University, Stanford, CA, United States

Iron-containing beta-amyloid plaques may play a key role in the development of Alzheimer’s disease (AD). To attempt to visualize the iron component of plaques, we performed high-resolution GRE imaging at 7.0T of AD specimens, and derived susceptibility maps from the phase images. Bright foci on the susceptibility maps corresponded closely with dark foci on the GRE images, suggesting plaques demonstrated positive magnetic susceptibility, possibly due to microscopic iron.

11:42 587.   Spectroscopic imaging of human medial temporal lobe epilepsy at 7T 
Jullie W Pan1, Dennis D Spencer1, R. Bradley Duckrow2, Nikolai Avdievich1, and Hoby P Hetherington1
1Neurosurgery, Yale University School of Medicine, New Haven, CT, United States, 2Neurology, Yale University School of Medicine, New Haven, CT, United States

The presence of unilateral hippocampal atrophy in the evaluation of medial temporal lobe epilepsy (MTLE) is often a defining factor that if concordant with the EEG and PET and not contraindicated from neuropsychological data, will typically result in candidacy for surgical resection. However, it is possible to have hippocampal atrophy (HA) without intractable seizures particularly in familial MTLE. We used ultra-high field MR spectroscopic imaging at 7T to assess MTLE with patients who are all HA positive. We studied n=12 patients who were medically intractable and n=2 patients who were very well controlled (seizure free for >2years on medication).

11:54 588.   Glutamate level in the frontal cortex decreases during young adulthood 
Anouk Marsman1, Dennis Klomp2, Jannie Wijnen2, Martijn Van den Heuvel1, Vincent Boer2, Peter Luijten2, and Hilleke Hulshoff Pol1
1Psychiatry, University Medical Center Utrecht, Utrecht, Netherlands, 2Radiology, University Medical Center Utrecht, Utrecht, Netherlands

Glutamate is the major excitatory neurotransmitter in the central nervous system and is involved in functions that alter with age. Using 1H-MRS (STEAM) at 7 Tesla, glutamate was measured in the medial frontal cortex of young adults, in which a decrease in glutamate concentration with increasing age was found. The decrease in glutamate concentration is in line with the gray matter thinning in medial frontal cortex in young adulthood. However, the change in glutamate is larger than the gray matter change, therefore we postulate that the observed effect is due to physiological changes rather than anatomical changes.

12:06 589.   Effect of normal aging on the Intra-cellular Sodium Volume Fraction in the Human Brain: a 7T MRI in-vivo study. 
Lazar Fleysher1, Niels Oesingmann2, Ryan Brown1, Hina Jaggi1, Graham Wiggins1, Daniel Sodickson1, and Matilde Inglese1,3
1Radiology, NYU School of Medicine, New York, New York, United States, 2Siemens Medical Solutions USA, Malvern, PA, United States, 3Neurology, NYU School of Medicine, New York, New York

Many morphologic MRI-based studies reported age-associated volume loss of the cerebral gray and white matters in normal aging. In this work, we report age-related changes in the tissue sodium concentration (TSC) in the healthy human brain. We find that TSC increases in gray and white matter with age consistent with cellular loss or shrinkage. The measured rate of fractional intracellular sodium volume fraction (ISVF) loss is found to be significantly different from the rate of fractional tissue volume loss for both GM and WM measured by morphologic MRI. This difference can be explained by the micro-structural changes in GM and WM associated with normal aging.

12:18 590.   Diffuse iron deposition in the putamen and caudate nucleus in CADASIL: comparing phase and magnitude images at 7 Tesla 
Michael Kwan-Yoe Liem1, Saskia A.J. Lesnik Oberstein2, Maarten J. Versluis1, Joost Haan3, Andrew G Webb1, Michel D Ferrari3, Mark A van Buchem1, and Jeroen van der Grond1
1Radiology, Leiden University Medical Center, Leiden, Netherlands, 2Clinical Genetics, Leiden University Medical Center, Leiden, Netherlands, 3Neurology, Leiden University Medical Center, Leiden, Netherlands

In this study we quantified diffuse iron deposition in cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL), using phase and magnitude imaging on 7 Tesla MRI. Twenty-five CADASIL patients and 15 healthy controls were examined using high resolution T2* imaging on 7 Tesla MRI. Increased phase shift and reduced signal intensity were found in the putamen and caudate nucleus of CADASIL patients which is likely caused by increased diffuse iron accumulation. In the cortex and white matter no signs of increased iron accumulation were found.