Magnetization Transfer Enhanced Vascular-space-occupancy (MT-VASO) MRI with Whole Brain Coverage

نویسندگان

  • J. Hua
  • D. Zaca
  • S. Jarso
  • J. J. Pillai
  • P. C. van Zijl
چکیده

Introduction: Vascular-space-occupancy (VASO) MRI (1) produces cerebral blood volume (CBV)-weighted images by employing inversion recovery to null the blood signal. Depending on the TR used, the residual magnetization in tissue, however, is only about 10-20% of the equilibrium signal intensity at the time of inversion (TI), which yields a relatively low signal-to-noise ratio (SNR). It has been demonstrate that by applying an MT pulse before the VASO inversion pulse (2), we can prepare a smaller tissue magnetization before inversion and accelerate the tissue recovery process after inversion to obtain a higher tissue signal and consequently boost the SNR and contrast-to-noise ratio (CNR), based on the fact that tissue signal can be strongly modulated by the MT pulse while blood has very little MT effect when using medium irradiating power and/or a frequency offset far away from water (>20ppm). Recent work (3,4) has shown that use of the 3D gradient spin echo (GraSE) sequence for the original VASO approach improves slice coverage and SNR/CNR, compared to using echo-planar-imaging (EPI). Here, the MT enhanced VASO (MTVASO) technique is extended from single-slice to whole-brain coverage using 3D GraSE sequence. The sensitivity (SNR) of this approach is compared to the widely used 2D multi-slice (MS) gradient echo (GE) EPI based conventional VASO protocol (5).

برای دانلود رایگان متن کامل این مقاله و بیش از 32 میلیون مقاله دیگر ابتدا ثبت نام کنید

ثبت نام

اگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید

منابع مشابه

Pathological Assessment of Brain White Matter in Relapsing-Remitting MS Patients using Quantitative Magnetization Transfer Imaging

Introduction: Multiple sclerosis (MS) is characterized by lesions in the white matter (WM) of the central nervous system. Magnetic resonance imaging is the most specific and sensitive method for diagnosis of multiple sclerosis. However, the ability of conventional MRI to show histopathologic heterogeneity of MS lesions is insufficient. Quantitative magnetization transfer imaging (qMTI) is a rel...

متن کامل

Application of whole-brain CBV-weighted fMRI to a cognitive stimulation paradigm: robust activation detection in a stroop task experiment using 3D GRASE VASO.

Brain activation studies generally utilize blood oxygenation level dependent (BOLD) contrast, most commonly measured using the gradient-echo echo-planar imaging (EPI) technique. BOLD contrast arises from regional changes in cerebral blood flow (CBF), cerebral blood volume (CBV), and the local metabolic rate of oxygen consumption. An alternative to BOLD is the detection of activation through dir...

متن کامل

The Assessment of Structural Changes in MS Plaques and Normal Appearing White Matter Using Quantitative Magnetization Transfer Imaging (MTI)

Introduction: Multiple sclerosis (MS) is a demyelinating disease of the central nervous system (CNS), affecting mostly young people at a mean age of 30 years. Magnetic resonance imaging (MRI) is one of the most specific and sensitive methods in diagnosing and detecting the evolution of multiple sclerosis disease. But it does not have the ability to differentiate between distinct histopathologic...

متن کامل

Applications and limitations of whole-brain MAGIC VASO functional imaging.

This work extends the multiple acquisitions with global inversion cycling vascular space occupancy (MAGIC VASO) method to human whole-brain functional magnetic resonance imaging (fMRI) at 3.0 Tesla and demonstrates the need to consider the dynamic contribution of cerebrospinal fluid (CSF) to the relative VASO signal change (DeltaVASO/VASO). Simulations were performed to determine the optimal sl...

متن کامل

HYPERBARIC OXYGEN THERAPY FOR MULTIPLE SCLEROSIS RELAPSE Protocol

Specific Aim 2: To determine whether use of hyperbaric oxygen impacts MRI parameters. MRI parameters will be evaluated at baseline and 6 months to determine: 2a) Thalamic volume loss 2b) Magnetization transfer ratio (MTR) change in baseline lesions. 2c) Magnetization transfer (MT) histogram whole brain and normal appearing brain tissue change (white matter and gray matter). 2d) Accumulation of ...

متن کامل

ذخیره در منابع من


  با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید

عنوان ژورنال:

دوره   شماره 

صفحات  -

تاریخ انتشار 2009