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

J Cereb Blood Flow Metab. 2021 Feb;41(2):336-341. doi: 10.1177/0271678X20914537. Epub 2020 Mar 24.

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.

Keywords: Gadolinium; contrast agent; penumbra; perfusion MRI; stroke.

MeSH terms

  • Contrast Media
  • Female
  • Gadolinium / metabolism*
  • Humans
  • Magnetic Resonance Imaging / methods*
  • Male
  • Perfusion Imaging / methods
  • Stroke / diagnostic imaging*

Substances

  • Contrast Media
  • Gadolinium