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Comparison of Tmax values between full- and half-dose gadolinium perfusion studies.

ABSTRACT: AHA guidelines recommend use of perfusion imaging for patient selection in the 6-24 h window. Recently, the safety of gadolinium-based contrast agents for MR perfusion imaging has been questioned based on findings that gadolinium accumulates in brain tissue. Regulatory bodies have recommended to limit the use of gadolinium-based contrast agents where possible. Focusing specifically on the time to maximum of the tissue residue function (Tmax) parameter, used in DAWN and DEFUSE 3, we hypothesized that half-dose scans would yield a similar Tmax delay pattern to full-dose scans. We prospectively recruited 10 acute ischemic stroke patients imaged with two perfusion scans at their follow-up visit, one with a standard dose gadolinium followed by a half-dose injection a median of 7 min apart. The brain was parcellated into a grid of 3 × 3 regions and the mean of the difference in Tmax between the 3 × 3 regions on the half- and full-dose Tmax maps was 0.1 s (iqr 0.38 s). The fraction of brain tissue that differed by no more than ±1 s was 93.7%. In patients with normal or modest Tmax delays, half-dose gadolinium appears to provide comparable Tmax measurements to those of full-dose scans.

SUBMITTER: Christensen S

PROVIDER: S-EPMC8370009 | biostudies-literature | 2021 Feb

REPOSITORIES: biostudies-literature

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Comparison of Tmax values between full- and half-dose gadolinium perfusion studies.

Christensen Søren S Amukotuwa Shalini S Lansberg Maarten G MG Kemp Stephanie S Heit Jeremy J JJ Mlynash Michael M Marks Michael P MP Albers Greg W GW Bammer Roland R

Journal of cerebral blood flow and metabolism : official journal of the International Society of Cerebral Blood Flow and Metabolism 20200324 2

AHA guidelines recommend use of perfusion imaging for patient selection in the 6-24 h window. Recently, the safety of gadolinium-based contrast agents for MR perfusion imaging has been questioned based on findings that gadolinium accumulates in brain tissue. Regulatory bodies have recommended to limit the use of gadolinium-based contrast agents where possible. Focusing specifically on the time to maximum of the tissue residue function (Tmax) parameter, used in DAWN and DEFUSE 3, we hypothesized ...[more]

PMID: 32208802

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Comparison of Tmax values between full- and half-dose gadolinium perfusion studies.

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Comparison of Tmax values between full- and half-dose gadolinium perfusion studies.

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