Fast 3D (1)H MRSI of the corticospinal tract in pediatric brain.
ABSTRACT To develop a (1)H magnetic resonance spectroscopic imaging (MRSI) sequence that can be used to image infants/children at 3T and by combining it with diffusion tensor imaging (DTI) tractography, extract relevant metabolic information corresponding to the corticospinal tract (CST).
A fast 3D MRSI sequence was developed for pediatric neuroimaging at 3T using spiral k-space readout and dual band RF pulses (32 x 32 x 8 cm field of view [FOV], 1 cc iso-resolution, TR/TE = 1500/130, 6:24 minute scan). Using DTI tractography to identify the motor tracts, spectra were extracted from the CSTs and quantified. Initial data from infants/children with suspected motor delay (n = 5) and age-matched controls (n = 3) were collected and N-acetylaspartate (NAA) ratios were quantified.
The average signal-to-noise ratio of the NAA peak from the studies was approximately 22. Metabolite profiles were successfully acquired from the CST by using DTI tractography. Decreased NAA ratios in those with motor delay compared to controls of approximately 10% at the CST were observed.
A fast and robust 3D MRSI technique targeted for pediatric neuroimaging has been developed. By combining with DTI tractography, metabolic information from the CSTs can be retrieved and estimated. By combining DTI and 3D MRSI, spectral information from various tracts can be obtained and processed.
Full-textDOI: · Available from: Daniel M Spielman, Oct 01, 2014
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ABSTRACT: Magnetic resonance imaging has been widely used noninvasively for pediatric neuroimaging for more than a decade. More recently, with advances in computing, functional techniques for imaging water diffusion, cellular metabolite levels, and blood flow are becoming available. Magnetic resonance spectroscopy imaging (MRSI) offers a snapshot of the metabolic status in the tissue of interest. It is complementary to the more traditionally used anatomic imaging for diagnoses of various abnormalities. This review describes the physical basis of proton MRSI, summarizes currently available techniques and their applications, highlights challenges of performing MRSI in the pediatric population, and previews the newest techniques currently on the horizon.Seminars in perinatology 02/2010; 34(1):20-7. DOI:10.1053/j.semperi.2009.10.003 · 2.42 Impact Factor
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