Dataset Information

Magnetic resonance thermometry at 7T for real-time monitoring and correction of ultrasound induced mild hyperthermia.

ABSTRACT: While Magnetic Resonance Thermometry (MRT) has been extensively utilized for non-invasive temperature measurement, there is limited data on the use of high field (?7T) scanners for this purpose. MR-guided Focused Ultrasound (MRgFUS) is a promising non-invasive method for localized hyperthermia and drug delivery. MRT based on the temperature sensitivity of the proton resonance frequency (PRF) has been implemented in both a tissue phantom and in vivo in a mouse Met-1 tumor model, using partial parallel imaging (PPI) to speed acquisition. An MRgFUS system capable of delivering a controlled 3D acoustic dose during real time MRT with proportional, integral, and derivative (PID) feedback control was developed and validated. Real-time MRT was validated in a tofu phantom with fluoroptic temperature measurements, and acoustic heating simulations were in good agreement with MR temperature maps. In an in vivo Met-1 mouse tumor, the real-time PID feedback control is capable of maintaining the desired temperature with high accuracy. We found that real time MR control of hyperthermia is feasible at high field, and k-space based PPI techniques may be implemented for increasing temporal resolution while maintaining temperature accuracy on the order of 1°C.

SUBMITTER: Fite BZ

PROVIDER: S-EPMC3335017 | biostudies-literature | 2012

REPOSITORIES: biostudies-literature

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Magnetic resonance thermometry at 7T for real-time monitoring and correction of ultrasound induced mild hyperthermia.

Fite Brett Z BZ Liu Yu Y Kruse Dustin E DE Caskey Charles F CF Walton Jeffrey H JH Lai Chun-Yen CY Mahakian Lisa M LM Larrat Benoit B Dumont Erik E Ferrara Katherine W KW

PloS one 20120420 4

While Magnetic Resonance Thermometry (MRT) has been extensively utilized for non-invasive temperature measurement, there is limited data on the use of high field (≥7T) scanners for this purpose. MR-guided Focused Ultrasound (MRgFUS) is a promising non-invasive method for localized hyperthermia and drug delivery. MRT based on the temperature sensitivity of the proton resonance frequency (PRF) has been implemented in both a tissue phantom and in vivo in a mouse Met-1 tumor model, using partial par ...[more]

PMID: 22536396

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Dataset Information

Magnetic resonance thermometry at 7T for real-time monitoring and correction of ultrasound induced mild hyperthermia.

Publications

Magnetic resonance thermometry at 7T for real-time monitoring and correction of ultrasound induced mild hyperthermia.

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