Merck
  • Home
  • Search Results
  • Acquisition strategy to reduce cerebrospinal fluid partial volume effects for improved DTI tractography.

Acquisition strategy to reduce cerebrospinal fluid partial volume effects for improved DTI tractography.

Magnetic resonance in medicine (2014-04-12)
Corey A Baron, Christian Beaulieu
ABSTRACT

An acquisition method that does not increase scan time or specific absorption rate is investigated for reducing the deleterious effects of cerebrospinal fluid (CSF) partial volume effects on diffusion tensor imaging (DTI) tractography. It is based on using a shorter repetition time (TR) by means of slice acquisition re-ordering to reduce the signal of long T1 CSF and a non-zero minimum diffusion weighting (b-value) to attenuate rapidly diffusing CSF signal with respect to brain tissue. A target reduction of the CSF/brain signal ratio from 3.5 to 0.8 required a TR of 2.5 s and minimum b-value of 425 s/mm(2) . This was evaluated at 4.7 Tesla in eight healthy young adults for tractography of the fornix, which has considerable CSF contamination and is difficult to track from standard DTI. This method effectively reduced CSF signal relative to brain and yielded more robust tractography, increased tract volume, increased fractional anisotropy, and decreased mean diffusivity in the fornix relative to standard DTI. CSF partial volume effects in DTI can be mitigated in acquisition through reduced TR and non-zero minimum diffusion weighting. The lack of RF absorption rate or scan time increases is attractive over other CSF suppression methods such as inversion recovery.

MATERIALS
Product Number
Brand
Product Description

Sigma-Aldrich
Tris(hydroxymethyl)aminomethane, ACS reagent, ≥99.8%
Sigma-Aldrich
Trizma® base, BioXtra, pH 10.5-12.0 (1 M in H2O), ≥99.9% (titration)
Sigma-Aldrich
Trizma® base, Primary Standard and Buffer, ≥99.9% (titration), crystalline
Sigma-Aldrich
Trizma® base, BioPerformance Certified, meets EP, USP testing specifications, suitable for cell culture, ≥99.9% (titration)
Sigma-Aldrich
Trizma® base, ≥99.9% (titration), crystalline
Sigma-Aldrich
Trizma® base, BioUltra, for molecular biology, ≥99.8% (T)
Sigma-Aldrich
Trizma® base, puriss. p.a., ≥99.7% (T)
Sigma-Aldrich
Trizma® base, ≥99.0% (T)
Supelco
Trizma® base, certified reference material for titrimetry, certified by BAM, ≥99.5%
Sigma-Aldrich
Trizma® base, anhydrous, free-flowing, Redi-Dri, ≥99.9%
Sigma-Aldrich
Tromethamine, meets USP testing specifications
Sigma-Aldrich
Sigma 7-9®, ≥99% (titration), crystalline
SAFC
Tromethamine
Trometamol, European Pharmacopoeia (EP) Reference Standard
Supelco
Tromethamine, pharmaceutical secondary standard, certified reference material