Dataset Information

Continuous prospectively navigated multi-echo GRE for improved BOLD imaging of the kidneys.

ABSTRACT: The objective of this study is to develop improved methods for renal blood oxygenation level dependent (BOLD) imaging. T2* mapping of the kidneys, or renal BOLD imaging, may depict renal oxygen levels and may be valuable as a noninvasive means of following the progression of renal disease. Current renal BOLD data is limited by imaging in a single breath hold, which results in low resolution and low signal-to-noise ratio (SNR). We compare a new free-breathing renal BOLD method with conventional breath-hold BOLD (BH-BOLD). A multi-echo GRE sequence with continuous prospective respiratory navigation and real-time feedback was developed that allows high resolution and high SNR renal BOLD imaging with constant sequence repetition time (TR) during free-breathing BOLD (FB-BOLD). The sequence was evaluated in 10 normal volunteers and compared with conventional BH-BOLD. Scan time for the FB-BOLD sequence was approximately three minutes, compared with 15 seconds for the BH-BOLD sequence. SNR of source images and residual error of T2* fitting were compared between the two methods. The FB-BOLD sequence produced motion-free T2* maps of the kidneys with SNR 1.9 times higher than BH-BOLD images. Residual error of T2* fitting was consistently lower in the right kidney with FB-BOLD (30% less than BH-BOLD) but higher in the left kidney (80% more than BH-BOLD), likely related to placement of the navigator on the right hemidiaphragm. A free-breathing prospectively navigated renal BOLD sequence allows flexible tradeoff between scan time, resolution, and SNR.

SUBMITTER: Morrell GR

PROVIDER: S-EPMC6476650 | biostudies-literature | 2019 May

REPOSITORIES: biostudies-literature

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Continuous prospectively navigated multi-echo GRE for improved BOLD imaging of the kidneys.

Morrell Glen Robert GR Jeong Eun-Kee EK Shi Xianfeng X Zhang Lei L Lee Vivian Shu-Ching VS

NMR in biomedicine 20190227 5

The objective of this study is to develop improved methods for renal blood oxygenation level dependent (BOLD) imaging. T2* mapping of the kidneys, or renal BOLD imaging, may depict renal oxygen levels and may be valuable as a noninvasive means of following the progression of renal disease. Current renal BOLD data is limited by imaging in a single breath hold, which results in low resolution and low signal-to-noise ratio (SNR). We compare a new free-breathing renal BOLD method with conventional b ...[more]

PMID: 30811061

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Dataset Information

Continuous prospectively navigated multi-echo GRE for improved BOLD imaging of the kidneys.

Publications

Continuous prospectively navigated multi-echo GRE for improved BOLD imaging of the kidneys.

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