Dataset Information

Quantitative assessment of cerebral venous blood T2 in mouse at 11.7T: Implementation, optimization, and age effect.

ABSTRACT: PURPOSE:To develop a non-contrast-agent MRI technique to quantify cerebral venous T2 in mice. METHODS:We implemented and optimized a T2 -relaxation-under-spin-tagging (TRUST) sequence on an 11.7 Tesla animal imaging system. A flow-sensitive-alternating-inversion-recovery (FAIR) module was used to generate control and label images, pair-wise subtraction of which yielded blood signals. Then, a T2 -preparation module was applied to produce T2 -weighted images, from which blood T2 was quantified. We conducted a series of technical studies to optimize the imaging slice position, inversion slab thickness, post-labeling delay (PLD), and repetition time. We also performed three physiological studies to examine the venous T2 dependence on hyperoxia (N?=?4), anesthesia (N?=?3), and brain aging (N?=?5). RESULTS:Our technical studies suggested that, for efficient data acquisition with minimal bias in estimated T2 , a preferred TRUST protocol was to place the imaging slice at the confluence of sagittal sinuses with an inversion-slab thickness of 2.5-mm, a PLD of 1000 ms and a repetition time of 3.5 s. Venous T2 values under normoxia and hyperoxia (inhaling pure oxygen) were 26.9?±?1.7 and 32.3?±?2.2 ms, respectively. Moreover, standard isoflurane anesthesia resulted in a higher venous T2 compared with dexmedetomidine anesthesia (N?=?3; P?=?0.01) which is more commonly used in animal functional MRI studies to preserve brain function. Venous T2 exhibited a decrease with age (N?=?5; P?

SUBMITTER: Wei Z

PROVIDER: S-EPMC5910286 | biostudies-literature | 2018 Aug

REPOSITORIES: biostudies-literature

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Quantitative assessment of cerebral venous blood T<sub>2</sub> in mouse at 11.7T: Implementation, optimization, and age effect.

Wei Zhiliang Z Xu Jiadi J Liu Peiying P Chen Lin L Li Wenbo W van Zijl Peter P Lu Hanzhang H

Magnetic resonance in medicine 20171221 2

<h4>Purpose</h4>To develop a non-contrast-agent MRI technique to quantify cerebral venous T<sub>2</sub> in mice.<h4>Methods</h4>We implemented and optimized a T<sub>2</sub> -relaxation-under-spin-tagging (TRUST) sequence on an 11.7 Tesla animal imaging system. A flow-sensitive-alternating-inversion-recovery (FAIR) module was used to generate control and label images, pair-wise subtraction of which yielded blood signals. Then, a T<sub>2</sub> -preparation module was applied to produce T<sub>2</su ...[more]

PMID: 29271045

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Dataset Information

Quantitative assessment of cerebral venous blood T2 in mouse at 11.7T: Implementation, optimization, and age effect.

Publications

Quantitative assessment of cerebral venous blood T<sub>2</sub> in mouse at 11.7T: Implementation, optimization, and age effect.

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