Optimization of spoiled gradient-echo phase imaging for in vivo localization of a focused ultrasound beam

Andrew H. Chung, Kullervo Hynynen, Vincent Colucci, Koichi Oshio, Harvey E. Cline, Ferenc A. Jolesz

Research output: Contribution to journalArticle

152 Citations (Scopus)

Abstract

The parameters of a spoiled gradient-echo (SPGR) pulse sequence have been optimized for in vivo localization of a focused ultrasound beam. Temperature elevation was measured by using the proton resonance frequency shift technique, and the phase difference signal-to-noise ratio (SNR(Δφ)) was estimated in skeletal muscle and kidney cortex in 10 rabbits. Optimized parameters included the echo time equivalent to T2* of the tissue, the longest repetition time possible with a 20-s sonication, and the flip angle equivalent to the Ernst angle. Optimal SPGR phase imaging can detect a sonication beam with a peak phase difference of 0.55 radian, which corresponds to a temperature elevation of 7.3°C. The sonication beam can be localized within one voxel (0.6 x 0.6 x 5 mm3) at power levels that are below the threshold for thermal damage of the tissue.

Original languageEnglish
Pages (from-to)745-752
Number of pages8
JournalMagnetic Resonance in Medicine
Volume36
Issue number5
DOIs
Publication statusPublished - 1996 Nov
Externally publishedYes

Fingerprint

Sonication
Kidney Cortex
Temperature
Signal-To-Noise Ratio
Protons
Skeletal Muscle
Hot Temperature
Rabbits

Keywords

  • focused ultrasound surgery
  • noninvasive thermometry
  • optimization
  • phase imaging

ASJC Scopus subject areas

  • Radiology Nuclear Medicine and imaging
  • Radiological and Ultrasound Technology

Cite this

Optimization of spoiled gradient-echo phase imaging for in vivo localization of a focused ultrasound beam. / Chung, Andrew H.; Hynynen, Kullervo; Colucci, Vincent; Oshio, Koichi; Cline, Harvey E.; Jolesz, Ferenc A.

In: Magnetic Resonance in Medicine, Vol. 36, No. 5, 11.1996, p. 745-752.

Research output: Contribution to journalArticle

Chung, Andrew H. ; Hynynen, Kullervo ; Colucci, Vincent ; Oshio, Koichi ; Cline, Harvey E. ; Jolesz, Ferenc A. / Optimization of spoiled gradient-echo phase imaging for in vivo localization of a focused ultrasound beam. In: Magnetic Resonance in Medicine. 1996 ; Vol. 36, No. 5. pp. 745-752.
@article{7f2a8a99785d45c399d1cec1cda12cab,
title = "Optimization of spoiled gradient-echo phase imaging for in vivo localization of a focused ultrasound beam",
abstract = "The parameters of a spoiled gradient-echo (SPGR) pulse sequence have been optimized for in vivo localization of a focused ultrasound beam. Temperature elevation was measured by using the proton resonance frequency shift technique, and the phase difference signal-to-noise ratio (SNR(Δφ)) was estimated in skeletal muscle and kidney cortex in 10 rabbits. Optimized parameters included the echo time equivalent to T2* of the tissue, the longest repetition time possible with a 20-s sonication, and the flip angle equivalent to the Ernst angle. Optimal SPGR phase imaging can detect a sonication beam with a peak phase difference of 0.55 radian, which corresponds to a temperature elevation of 7.3°C. The sonication beam can be localized within one voxel (0.6 x 0.6 x 5 mm3) at power levels that are below the threshold for thermal damage of the tissue.",
keywords = "focused ultrasound surgery, noninvasive thermometry, optimization, phase imaging",
author = "Chung, {Andrew H.} and Kullervo Hynynen and Vincent Colucci and Koichi Oshio and Cline, {Harvey E.} and Jolesz, {Ferenc A.}",
year = "1996",
month = "11",
doi = "10.1002/mrm.1910360513",
language = "English",
volume = "36",
pages = "745--752",
journal = "Magnetic Resonance in Medicine",
issn = "0740-3194",
publisher = "John Wiley and Sons Inc.",
number = "5",

}

TY - JOUR

T1 - Optimization of spoiled gradient-echo phase imaging for in vivo localization of a focused ultrasound beam

AU - Chung, Andrew H.

AU - Hynynen, Kullervo

AU - Colucci, Vincent

AU - Oshio, Koichi

AU - Cline, Harvey E.

AU - Jolesz, Ferenc A.

PY - 1996/11

Y1 - 1996/11

N2 - The parameters of a spoiled gradient-echo (SPGR) pulse sequence have been optimized for in vivo localization of a focused ultrasound beam. Temperature elevation was measured by using the proton resonance frequency shift technique, and the phase difference signal-to-noise ratio (SNR(Δφ)) was estimated in skeletal muscle and kidney cortex in 10 rabbits. Optimized parameters included the echo time equivalent to T2* of the tissue, the longest repetition time possible with a 20-s sonication, and the flip angle equivalent to the Ernst angle. Optimal SPGR phase imaging can detect a sonication beam with a peak phase difference of 0.55 radian, which corresponds to a temperature elevation of 7.3°C. The sonication beam can be localized within one voxel (0.6 x 0.6 x 5 mm3) at power levels that are below the threshold for thermal damage of the tissue.

AB - The parameters of a spoiled gradient-echo (SPGR) pulse sequence have been optimized for in vivo localization of a focused ultrasound beam. Temperature elevation was measured by using the proton resonance frequency shift technique, and the phase difference signal-to-noise ratio (SNR(Δφ)) was estimated in skeletal muscle and kidney cortex in 10 rabbits. Optimized parameters included the echo time equivalent to T2* of the tissue, the longest repetition time possible with a 20-s sonication, and the flip angle equivalent to the Ernst angle. Optimal SPGR phase imaging can detect a sonication beam with a peak phase difference of 0.55 radian, which corresponds to a temperature elevation of 7.3°C. The sonication beam can be localized within one voxel (0.6 x 0.6 x 5 mm3) at power levels that are below the threshold for thermal damage of the tissue.

KW - focused ultrasound surgery

KW - noninvasive thermometry

KW - optimization

KW - phase imaging

UR - http://www.scopus.com/inward/record.url?scp=0029958301&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=0029958301&partnerID=8YFLogxK

U2 - 10.1002/mrm.1910360513

DO - 10.1002/mrm.1910360513

M3 - Article

VL - 36

SP - 745

EP - 752

JO - Magnetic Resonance in Medicine

JF - Magnetic Resonance in Medicine

SN - 0740-3194

IS - 5

ER -