Synthetic T2 mapping is correlated with time from stroke onset: a future tool in wake-up stroke management?
- 174 Downloads
FLAIR-DWI mismatch is an effective method to select eligible wake-up stroke (WUS) patients for intravenous thrombolysis, but shows limitations in the case of subtle FLAIR hyperintensities. T2 mapping is a quantitative method, directly generated from synthetic MRI, which provides T2 relaxation times. We aimed to assess the correlation between T2 values and onset time in acute stroke patients.
We prospectively included stroke patients in the 4.5-h window undergoing brain MRI including MAGnetic resonance Image Compilation (MAGiC) from March to October 2017. T2 relaxation times and FLAIR signal intensities were measured in ischemic and contralateral nonischemic regions to calculate FLAIR signal intensity ratio (rSI), difference, and ratio of T2 values. Correlation analysis with time from the onset was achieved using Pearson or Spearman correlation coefficient (ρ) test.
Forty-two patients were included. The strongest correlation with the time from onset was the difference in T2 relaxation times (ρ = 0.71; CI95% = [0.48; 0.85]), followed by the ratio (ρ = 0.65; CI95% = [0.37; 0.82]) and the absolute T2 relaxation time (ρ = 0.4; CI95% = [0.06; 0.66]), whereas the FLAIR rSI showed the weakest correlation (ρ = 0.18; CI95% = [− 0.16–0.51]).
The difference and ratio in T2 relaxation times were correlated with the onset time in stroke patients in the 4.5-h window. T2 mapping generated from synthetic MRI may become a relevant tool to select WUS patients with subtle FLAIR hyperintensities. Given that no definitive statement can be made about its usefulness in the 4.5-h windows, further study including patients with an onset time > 4.5 h is required.
• The difference and ratio in T2 relaxation times are each individually correlated with the time from stroke onset in the 4.5-h window.
• FLAIR rSI showed a poor correlation with the time from stroke onset.
• T2 mapping, directly generated from synthetic MRI, may be a suitable quantitative marker to select safely WUS patients with subtle FLAIR hyperintensities for intravenous thrombolysis.
KeywordsStroke Acute stroke Magnetic resonance imaging
MAGnetic resonance Imaging Compilation
National Institutes of Health Stroke Scale
Signal intensity ratio
The authors state that this work has not received any funding.
Compliance with ethical standards
The scientific guarantor of this publication is Pr Sebastien Verclytte.
Conflict of interest
The authors of this manuscript declare no relationships with any companies whose products or services may be related to the subject matter of the article.
Statistics and biometry
One of the authors has significant statistical expertise.
Written informed consent was waived by the Institutional Review Board.
Institutional Review Board approval was obtained.
• Performed at one institution
- 2.Thomalla G, Boutitie F, Fiebach JB et al (2017) Stroke with unknown time of symptom onset: baseline clinical and magnetic resonance imaging data of the first thousand patients in WAKE-UP (efficacy and safety of MRI-based thrombolysis in wake-up stroke: a randomized, doubleblind, placebo-controlled trial). Stroke 48:770–773. https://doi.org/10.1161/STROKEAHA.116.015233 CrossRefPubMedGoogle Scholar
- 3.Powers WJ, Rabinstein AA, Ackerson T et al (2018) 2018 guidelines for the early management of patients with acute ischemic stroke: a guideline for healthcare professionals from the American Heart Association/American Stroke Association. Stroke. 49:e46–e99. https://doi.org/10.1161/STR.0000000000000158 CrossRefPubMedGoogle Scholar
- 6.Thomalla G, Simonsen CZ, Boutitie F et al (2018) MRI-guided thrombolysis for stroke with unknown time of onset. N Engl J Med. https://doi.org/10.1056/NEJMoa1804355
- 8.Ebinger M, Galinovic I, Rozanski M, Brunecker P, Endres M, Fiebach JB (2010) Fluid-attenuated inversion recovery evolution within 12 hours from stroke onset: a reliable tissue clock? Stroke 41:250–255. https://doi.org/10.1161/STROKEAHA.109.568410
- 9.Cheng B, Brinkmann M, Forkert ND et al (2013) Quantitative measurements of relative fluid-attenuated inversion recovery (FLAIR) signal intensities in acute stroke for the prediction of time from symptom onset. J Cereb Blood Flow Metab 33:76–84. https://doi.org/10.1038/jcbfm.2012.129 CrossRefPubMedGoogle Scholar
- 10.Blystad I, Warntjes JBM, Smedby Ö, Lundberg P, Larsson EM, Tisell A (2017) Quantitative MRI for analysis of peritumoral edema in malignant gliomas. PLoS One 12:e0177135. https://doi.org/10.1371/journal.pone.0177135
- 11.Namer IJ, Waydelich R, Armspach JP, Hirsch E, Marescaux C, Grucker D (1998) Contribution of T2 relaxation time mapping in the evaluation of cryptogenic temporal lobe epilepsy. Neuroimage 7:304–313. https://doi.org/10.1006/nimg.1998.0331
- 12.Jackson GD, Connelly A, Duncan JS, Grünewald RA, Gadian DG (1993) Detection of hippocampal pathology in intractable partial epilepsy: increased sensitivity with quantitative magnetic resonance T2 relaxometry. Neurology 43:1793–1799Google Scholar
- 13.Rugg-Gunn FJ, Boulby PA, Symms MR, Barker GJ, Duncan JS (2005) Whole-brain T2 mapping demonstrates occult abnormalities in focal epilepsy. Neurology 64:318–325. https://doi.org/10.1212/01.WNL.0000149642.93493.F4
- 14.Bonnier G, Maréchal B, Fartaria MJ et al (2017) The combined quantification and interpretation of multiple quantitative magnetic resonance imaging metrics enlightens longitudinal changes compatible with brain repair in relapsing-remitting multiple sclerosis patients. Front Neurol 8:506. https://doi.org/10.3389/fneur.2017.00506 CrossRefPubMedPubMedCentralGoogle Scholar
- 19.Siemonsen S, Löbel U, Sedlacik J et al (2012) Elevated T2-values in MRI of stroke patients shortly after symptom onset do not predict irreversible tissue infarction. Brain 135:1981–1989. https://doi.org/10.1093/brain/aws079
- 21.Hagiwara A, Hori M, Cohen-Adad J et al (2018) Linearity, bias, intrascanner repeatability, and interscanner reproducibility of quantitative multidynamic multiecho sequence for rapid simultaneous relaxometry at 3 T: a validation study with a standardized phantom and healthy controls. Invest Radiol 54:39–47. https://doi.org/10.1097/RLI.0000000000000510
- 22.Brott T, Adams HP Jr, Olinger CP et al (1989) Measurements of acute cerebral infarction: a clinical examination scale. Stroke 20:864–870Google Scholar
- 24.Wansapura JP, Holland SK, Dunn RS, Ball WS Jr (1999) NMR relaxation times in the human brain at 3.0 tesla. J Magn Reson Imaging 9:531–538Google Scholar
- 25.Thomalla G, Cheng B, Ebinger M et al (2011) DWI-FLAIR mismatch for the identification of patients with acute ischaemic stroke within 4·5 h of symptom onset (PRE-FLAIR): a multicentre observational study. Lancet Neurol 10:978–986. https://doi.org/10.1016/S1474-4422(11)70192-2 CrossRefPubMedGoogle Scholar