T<sub>1</sub><sub>ρ</sub> mapping for the evaluation of high intensity focused ultrasound tumor treatment

Hectors, Stefanie; Moonen, Rik P. M.; Strijkers, Gustav J.; Nicolay, Klaas

doi:10.1002/mrm.25269

Cited by 8 publications

(10 citation statements)

References 36 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…This can ultimately lead to extrusion of water from the treated tissue, which has been addressed previously in a study on changes in MR properties of various tissues after thermal treatment (36). In our recent study on T 1r after HIFU treatment of murine tumors, we observed signs for this denaturation-induced extrusion of water (49). While the protein denaturation itself did not lead to direct change in the tumor T 1r values, at 3 days after treatment a significant approximately 15% decrease in T 1r was observed in the treated tumors compared with baseline measurements.…”

Section: Inflammatory Response and Edema Formationmentioning

confidence: 57%

“…T 1ρ is sensitive to interactions between water molecules and macromolecules, predominantly proteins , that occur around the carrier frequency of the applied spin‐lock pulse. However, in a recent study, we did not observe a difference in tumor T 1ρ before and directly after HIFU treatment of subcutaneous mouse tumors, which suggested that T 1ρ is apparently not directly sensitive to protein denaturation occurring instantly during HIFU application .…”

Section: Mri‐detectable Hifu Treatment Effectsmentioning

confidence: 99%

See 1 more Smart Citation

MRI methods for the evaluation of high intensity focused ultrasound tumor treatment: Current status and future needs

Hectors

Jacobs

Moonen

et al. 2015

Magnetic Resonance in Med

Self Cite

View full text Add to dashboard Cite

Thermal ablation with high intensity focused ultrasound (HIFU) is an emerging noninvasive technique for the treatment of solid tumors. HIFU treatment of malignant tumors requires accurate treatment planning, monitoring and evaluation, which can be facilitated by performing the procedure in an MR-guided HIFU system. The MR-based evaluation of HIFU treatment is most often restricted to contrast-enhanced T 1 -weighted imaging, while it has been shown that the non-perfused volume may not reflect the extent of nonviable tumor tissue after HIFU treatment. There are multiple studies in which more advanced MRI methods were assessed for their suitability for the evaluation of HIFU treatment. While several of these methods seem promising regarding their sensitivity to HIFU-induced tissue changes, there is still ample room for improvement of MRI protocols for HIFU treatment evaluation. In this review article, we describe the major acute and delayed effects of HIFU treatment. For each effect, the MRI methods that have beenor could be-used to detect the associated tissue changes are described. In addition, the potential value of multiparametric MRI for the evaluation of HIFU treatment is discussed. The review ends with a discussion on future directions for the MRIbased evaluation of HIFU treatment. Magn Reson Med 75:302-317, 2016. V C 2015 Wiley Periodicals, Inc.

show abstract

Section: Inflammatory Response and Edema Formationmentioning

confidence: 57%

Section: Mri‐detectable Hifu Treatment Effectsmentioning

confidence: 99%

MRI methods for the evaluation of high intensity focused ultrasound tumor treatment: Current status and future needs

Hectors

Jacobs

Moonen

et al. 2015

Magnetic Resonance in Med

Self Cite

View full text Add to dashboard Cite

show abstract

“…Additional recent applications of these techniques can be found in refs. . The main strength of T 1 ρ and T 2 ρ MRI, i.e.…”

Section: Summary Of T1ρ and T2ρ Mri Techniquesmentioning

confidence: 97%

“…Additional recent applications of these techniques can be found in refs. (74,(104)(105)(106)(107)(108)(109)(110)(111)(112)(113)(114)(115)(116). The main strength of T 1ρ and T 2ρ MRI, i.e.…”

Section: Summary Of T 1ρ and T 2ρ Mri Techniquesmentioning

confidence: 99%

Quantitative rotating frame relaxometry methods in MRI

Gilani

Sepponen

2016

NMR Biomed.

View full text Add to dashboard Cite

Macromolecular degeneration and biochemical changes in tissue can be quantified using rotating frame relaxometry in MRI. It has been shown in several studies that the rotating frame longitudinal relaxation rate constant (R1ρ ) and the rotating frame transverse relaxation rate constant (R2ρ ) are sensitive biomarkers of phenomena at the cellular level. In this comprehensive review, existing MRI methods for probing the biophysical mechanisms that affect the rotating frame relaxation rates of the tissue (i.e. R1ρ and R2ρ ) are presented. Long acquisition times and high radiofrequency (RF) energy deposition into tissue during the process of spin-locking in rotating frame relaxometry are the major barriers to the establishment of these relaxation contrasts at high magnetic fields. Therefore, clinical applications of R1ρ and R2ρ MRI using on- or off-resonance RF excitation methods remain challenging. Accordingly, this review describes the theoretical and experimental approaches to the design of hard RF pulse cluster- and adiabatic RF pulse-based excitation schemes for accurate and precise measurements of R1ρ and R2ρ . The merits and drawbacks of different MRI acquisition strategies for quantitative relaxation rate measurement in the rotating frame regime are reviewed. In addition, this review summarizes current clinical applications of rotating frame MRI sequences. Copyright © 2016 John Wiley & Sons, Ltd.

show abstract

“…In addition, we aimed to compare the performance of this optimal multiparametric analysis with conventional HIFU monitoring and evaluation methods, namely MR thermometry and contrast-enhanced MRI. Such quantitative comparison with conventional techniques could not be performed in our previous studies (13,21,22), mainly because the HIFU treatment was performed outside the MR system. In the present study, the HIFU treatment was performed in a rat tumor model on a clinical 3 T MR-HIFU system, allowing for real-time acquisition of MR temperature maps during treatment.…”

Section: Introductionmentioning

confidence: 98%

Multiparametric MRI analysis for the evaluation of MR‐guided high intensity focused ultrasound tumor treatment

et al. 2015

Self Cite

View full text Add to dashboard Cite

Nicolay, K. (2015). Multiparametric MRI analysis for the evaluation of MR-guided high intensity focused ultrasound tumor treatment. NMR in Biomedicine, 28(9), 1125-1140. DOI: 10.1002/nbm.3350 General rightsCopyright and moral rights for the publications made accessible in the public portal are retained by the authors and/or other copyright owners and it is a condition of accessing publications that users recognise and abide by the legal requirements associated with these rights.• Users may download and print one copy of any publication from the public portal for the purpose of private study or research.• You may not further distribute the material or use it for any profit-making activity or commercial gain • You may freely distribute the URL identifying the publication in the public portal ? Take down policyIf you believe that this document breaches copyright please contact us providing details, and we will remove access to the work immediately and investigate your claim. For the clinical application of high intensity focused ultrasound (HIFU) for thermal ablation of malignant tumors, accurate treatment evaluation is of key importance. In this study, we have employed a multiparametric MRI protocol, consisting of quantitative T 1 , T 2 , ADC, amide proton transfer (APT), T 1ρ and DCE-MRI measurements, to evaluate MR-guided HIFU treatment of subcutaneous tumors in rats. K-means clustering using all different combinations of the endogenous contrast MRI parameters (feature vectors) was performed to segment the multiparametric data into tissue populations with similar MR parameter values. The optimal feature vector for identification of the extent of non-viable tumor tissue after HIFU treatment was determined by quantitative comparison between clustering-derived and histology-derived non-viable tumor fractions. The highest one-to-one correspondence between these clustering-based and histology-based non-viable tumor fractions was observed for the feature vector {ADC, APT-weighted signal} (R 2 to line of identity (R 2 y=x ) = 0.92) and the strongest agreement was seen 3 days after HIFU (R 2 y=x = 0.97). To compare the multiparametric MRI analysis results with conventional HIFU monitoring and evaluation methods, the histology-derived non-viable tumor fractions were also quantitatively compared with nonperfused tumor fractions (derived from the level of contrast enhancement in the DCE-MRI measurements) and 240 CEM tumor fractions (i.e. thermal dose > 240 cumulative equivalent minutes at 43°C). The correlation between histology-derived non-viable tumor fractions directly after HIFU and the 240 CEM fractions was high, but not significant. The non-perfused fractions overestimated the extent of non-viable tumor tissue directly after HIFU, whereas an underestimation was observed 3 days after HIFU.In conclusion, we have shown that a multiparametric MR analysis, especially based on the ADC and the APTweighted signal, can potentially be used to determine the extent of non-viable tumor tissue 3 days after HIFU treatment. We expe...

show abstract

T₁_ρ mapping for the evaluation of high intensity focused ultrasound tumor treatment

Cited by 8 publications

References 36 publications

MRI methods for the evaluation of high intensity focused ultrasound tumor treatment: Current status and future needs

MRI methods for the evaluation of high intensity focused ultrasound tumor treatment: Current status and future needs

Quantitative rotating frame relaxometry methods in MRI

Multiparametric MRI analysis for the evaluation of MR‐guided high intensity focused ultrasound tumor treatment

Contact Info

Product

Resources

About

T1ρ mapping for the evaluation of high intensity focused ultrasound tumor treatment

Cited by 8 publications

References 36 publications

MRI methods for the evaluation of high intensity focused ultrasound tumor treatment: Current status and future needs

MRI methods for the evaluation of high intensity focused ultrasound tumor treatment: Current status and future needs

Quantitative rotating frame relaxometry methods in MRI

Multiparametric MRI analysis for the evaluation of MR‐guided high intensity focused ultrasound tumor treatment

Contact Info

Product

Resources

About

T₁_ρ mapping for the evaluation of high intensity focused ultrasound tumor treatment