Dataset Information

Fast measurement of blood T₁ in the human carotid artery at 3T: Accuracy, precision, and reproducibility.

ABSTRACT:

Purpose

To develop a fast protocol for measuring T₁ values in the internal carotid artery (ICA), to validate this technique with in vitro measurements, and to evaluate its reproducibility.

Methods

A modified Look-Locker sequence was optimized to enable rapid determination of T₁ in the ICA at 3T. T₁ values from the ICA were compared with in vitro measurements on individually sampled venous blood oxygenated to arterial levels. A test-retest reproducibility study was also conducted.

Results

The group-averaged arterial blood T₁ value was 1908 ± 77 ms for six women (hematocrit = 0.39 ± 0.03) and 1785 ± 55 ms for seven men (hematocrit = 0.45 ± 0.02), which is 100-200 ms longer than the widely adopted value obtained from bovine blood experiments. The arterial T₁ value per subject correlated significantly with individual hematocrit values. The intrasession and intersession coefficients of variation were 1.1% and 2.1%, respectively, indicating good precision and reproducibility of our method. Reasonable agreement was observed between the in vivo and in vitro results with a correlation coefficient of 0.78.

Conclusion

The proposed method can provide fast arterial T₁ measurement on individual subjects. When not performing such a subject-specific measurement, we recommend the use of 1908 ms and 1785 ms for healthy women and men, respectively, or 1841 ms for adults in general. Magn Reson Med 77:2296-2302, 2017. © 2016 International Society for Magnetic Resonance in Medicine.

SUBMITTER: Li W

PROVIDER: S-EPMC5250597 | biostudies-literature | 2017 Jun

REPOSITORIES: biostudies-literature

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Publications

Fast measurement of blood T<sub>1</sub> in the human carotid artery at 3T: Accuracy, precision, and reproducibility.

Li Wenbo W Liu Peiying P Lu Hanzhang H Strouse John J JJ van Zijl Peter C M PCM Qin Qin Q

Magnetic resonance in medicine 20160720 6

<h4>Purpose</h4>To develop a fast protocol for measuring T<sub>1</sub> values in the internal carotid artery (ICA), to validate this technique with in vitro measurements, and to evaluate its reproducibility.<h4>Methods</h4>A modified Look-Locker sequence was optimized to enable rapid determination of T<sub>1</sub> in the ICA at 3T. T<sub>1</sub> values from the ICA were compared with in vitro measurements on individually sampled venous blood oxygenated to arterial levels. A test-retest reproduci ...[more]

PMID: 27436420

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Dataset Information

Fast measurement of blood T₁ in the human carotid artery at 3T: Accuracy, precision, and reproducibility.

Purpose

Methods

Results

Conclusion

Publications

Fast measurement of blood T<sub>1</sub> in the human carotid artery at 3T: Accuracy, precision, and reproducibility.

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure

Tweets

Dataset Information

Fast measurement of blood T1 in the human carotid artery at 3T: Accuracy, precision, and reproducibility.

Purpose

Methods

Results

Conclusion

Publications

Fast measurement of blood T<sub>1</sub> in the human carotid artery at 3T: Accuracy, precision, and reproducibility.

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure

Tweets

Fast measurement of blood T₁ in the human carotid artery at 3T: Accuracy, precision, and reproducibility.