T-1 rho Mapping for the Evaluation of High Intensity Focused Ultrasound Tumor Treatment

Stefanie J. C. G. Hectors*, Rik P. M. Moonen, Gustav J. Strijkers, Klaas Nicolay

*Corresponding author for this work

Research output: Contribution to journalArticleAcademicpeer-review

5 Citations (Web of Science)


This study was aimed to assess the effects of High Intensity Focused Ultrasound (HIFU) thermal ablation on tumor T1? .In vivo T1? measurements of murine tumors at various spin-lock amplitudes (B1 = 0-2000 Hz) were performed before (n = 13), directly after (n = 13) and 3 days (n = 7) after HIFU treatment. T2 maps were obtained from the measurements at B1 = 0 Hz.Average tumor T1? distributions at the different experimental time points showed a shift toward lower T1? values after HIFU for all spin-lock amplitudes, which became larger with increasing spin-lock amplitude at 3 days after treatment. Statistical analysis confirmed a significant effect of spin-lock amplitude on the average change in T1? (?T1? ) as compared to baseline at 3 days after HIFU. At 3 days after treatment, ?T1? values at B1 above 100 Hz were significantly lower (more negative) than at B1 = 0 Hz (T2 ).Significant changes in tumor T1? were observed after HIFU treatment. These T1? changes were distinctly more pronounced than HIFU-induced changes in T2 . The results indicate that T1? imaging is sensitive to HIFU-induced tissue changes and may thus be a suitable MR method for the evaluation of HIFU treatment. Magn Reson Med 73:1593-1601, 2015. ? 2014? 2014
Original languageEnglish
Pages (from-to)1593-1601
JournalMagnetic Resonance in Medicine
Issue number4
Publication statusPublished - Apr 2015


  • T-1
  • spin-lock
  • high intensity focused ultrasound
  • cancer treatment response

Cite this