Simultaneous measurements of temperature and pHin vivo using NMR in conjunction with TmDOTP5?

Sun, Yang; Sugawara, Michio; Mulkern, Robert V.; Hynynen, Kullervo; Mochizuki, Seibu; Albert, Mitchell S.; Chen, Zuo

doi:10.1002/nbm.676

Cited by 38 publications

(33 citation statements)

References 27 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…This complex also had temperature dependence in its [31]P signal, and the coefficient was 2.18 ppm/ C in vitro. Because this complex also has pH sensitivity in its proton chemical shifts, we can determine both temperature and pH simultaneously using two different proton signals, such as H 6 , as mentioned above, and H 2 at around +80 ppm [87,88].…”

Section: The Lanthanide Complexmentioning

confidence: 99%

Noninvasive Temperature Monitoring

Kuroda

2016

Hyperthermic Oncology From Bench to Bedside

View full text Add to dashboard Cite

Noninvasive thermometry of target tissue is one of the key issues for successful and safe thermal therapy. Although various techniques using X-ray, infrared, photoacoustics, radiometry, impedance, ultrasound, and magnetic resonance imaging (MRI) have been investigated, to date, infrared imaging for skin surface or MRI for cross-sectional temperature distribution is accepted as a tool for clinical use. Since cross-sectional temperature distribution deep inside a human body is important in thermal therapy in general, practically, MRI is the only practical modality applicable for the therapies. Among several intrinsic MR parameters including proton density, spin-lattice relaxation time, spin-spin relaxation time, diffusion coefficient and chemical shift, the chemical shift is known to be the most reliable for temperature imaging in aqueous tissues. Because this parameter can be measured only from the resonance frequency of water protons and hence independent from the other parameters, which are measured based on the intensity of the MR signals. Phase mapping or spectroscopic technique are applicable for measuring and/or imaging distribution of temperature change. For adipose tissue spin-lattice relaxation time of fat may be used.

show abstract

Section: The Lanthanide Complexmentioning

confidence: 99%

Noninvasive Temperature Monitoring

Kuroda

2016

Hyperthermic Oncology From Bench to Bedside

View full text Add to dashboard Cite

show abstract

“…Tm 3þ , Tb 3þ and Dy 3þ induce the largest paramagnetic shifts [33]. The agents that have been suggested for MR thermometry include praseodymium 10-(2-methoxyethyl)-1, 4, 7, 10-tetraazacyclododecane-1, 4, 7-triacetate (Pr[MOE-DO3A]) (16)(17)(18)(19)(20)(21)(22), thulium 1, 4, 7, 10-tetraazacyclododecane-1, 4, 7, 10-tetrakis-(methylene phosphonate) (TmDOTP 5À ) [23][24][25][26], thulium 1, 4, 7, 10-tetraazacyclododecane-1, 4, 7, 10-tetraacetate (TmDOTA À ) [27,28] and Yb 3þ , Pr 3þ , Tm 3þ , Tb 3þ and Dy 3þ complexes of 1, 4, 7, 10-tetraazacyclododecane-, 0 , 00 , 000 -tetramethyl-1, 4, 7, 10-tetraacetate (DOTMA 4À ) [29][30][31]. The chemical structures and some of the important features of these complexes are listed in Table I.…”

Section: Mr Thermometry With Paramagnetic Lanthanide Complexesmentioning

confidence: 99%

“…The feasibility of MR thermometry based on the strong temperature dependence of the hyperfine chemical shifts of many paramagnetic complexes has been explored [16][17][18][19][20][21][22][23][24][25][26][27][28][29][30][31]. The observed chemical shift, obs , of a nucleus in a paramagnetic complex is composed of contributions from a diamagnetic term, dia , a paramagnetic contact term, con , and a paramagnetic dipole term, dip [32]:…”

Section: Mr Thermometry With Paramagnetic Lanthanide Complexesmentioning

confidence: 99%

Noninvasive thermometry using hyperfine-shifted MR signals from paramagnetic lanthanide complexes

Hekmatyar

Kerkhoff

Pakin

et al. 2005

International Journal of Hyperthermia

View full text Add to dashboard Cite

MR thermometry techniques based on the strong water 1H signal provide high spatial and temporal resolution and have shown promise for applications such as laser surgery and RF ablation. However, these techniques have low temperature sensitivity for hyperthermia applications and are greatly influenced by local motion and susceptibility variations. 1H NMR signals from paramagnetic lanthanide complexes of Pr3+, Yb3+ and Tm3+ show up to 300-fold stronger temperature dependence compared to the water 1H signal. In addition, 1H chemical shifts of many of these complexes are insensitive to other factors such as the concentration of the paramagnetic complex, pH, [Ca2+], and the presence of plasma macro-molecules and ions. Applications of lanthanide complexes for temperature measurement in intact animals and the feasibility of mapping temperatures in phantoms have been demonstrated. Among all the lanthanide complexes examined so far, thulium 1, 4, 7, 10-tetramethyl-1, 4, 7, 10-tetraazacyclododecane-1, 4, 7, 10-tetraacetate (TmDOTMA-) appears to be the most attractive for in vivo MR thermometry. The 1H signal from the methyl groups on this complex is relatively intense because of 12 equivalent protons and provides high temperature sensitivity because of the large paramagnetic shifts induced by thulium. The possibility of imaging TmDOTMA2--in intact animals at physiologically safe concentrations has recently been demonstrated. Overall, MR thermometry methods based on hyperfine-shifted MR signals from paramagnetic lanthanide complexes appear promising for animal applications, but further studies relating to acceptable dose and signal-to-noise ratio are necessary before clinical use.

show abstract

“…Because this complex also has pH sensitivity in its proton chemical shifts, both temperature and pH can be determined simultaneously using two different proton signals, such as H 6 , as mentioned, and a H2 signal at around +80 ppm. 41,62 Although these lanthanide complexes are capable of measuring absolute temperature in vivo with markedly higher sensitivity than water, their toxicity makes their application to humans problematic. Nevertheless, in vivo measurements at dosages of 1-2 mmol kg −1 may be possible.…”

Section: The Temperature Dependence Of Chemical Shifts Not Involving mentioning

confidence: 99%

Temperature Monitoring Using Chemical Shift

Kuroda

2016

eMagRes

View full text Add to dashboard Cite

Methodologies in MRS provide noninvasive thermometry with a number of temperature-dependent MR parameters. Among these, the most representative is the proton chemical shift of the hydroxyl group. The electronic shielding effect of protons in this group changes linearly with temperature owing to intermolecular hydrogen bonding. Internally referenced measurements of the chemical shift difference between water and the protons in methyl or ethyl groups, whose frequencies are temperature insensitive, can provide precise measures of temperature. The proton chemical shift differences between water and N-acetylaspartate, creatine, choline, and the methylene chain in fat, or the relative change of the water proton chemical shift, may be used to monitor temperature in biological tissues. However, factors such as bulk susceptibility, electrolytes, pH, and macromolecules also affect chemical shifts in tissues. Although the internal reference technique can reduce the susceptibility effect, the bond-breaking effect of electrolytes can alter the absolute value, as well as the temperature coefficient of the chemical shift. Thus, absolute temperature monitoring in vivo has not been achieved to date. Nevertheless, monitoring relative temperature differences is useful. Alternative methodologies for MRS temperature monitoring include the use of proton chemical shifts in lanthanide complexes, chemical exchange saturation transfer agents, nonproton nuclei, spectroscopic T 1 measurements, and quantum coherence.

show abstract

Simultaneous measurements of temperature and pHin vivo using NMR in conjunction with TmDOTP5?

Cited by 38 publications

References 27 publications

Noninvasive Temperature Monitoring

Noninvasive Temperature Monitoring

Noninvasive thermometry using hyperfine-shifted MR signals from paramagnetic lanthanide complexes

Temperature Monitoring Using Chemical Shift

Contact Info

Product

Resources

About