Intraoperative diffusion-weighted imaging for visualization of the pyramidal tracts. Part I

Pre-clinical validation of the scanning protocol

N. Ozawa, Y. Muragaki, R. Nakamura, Hiroshi Iseki

Research output: Contribution to journalArticle

10 Citations (Scopus)

Abstract

Integration of intraoperative diffusion-weighted imaging (iDWI) into neuronavigation can be potentially useful for identification of the pyramidal tract during surgery for parenchymal brain lesions. The technique of iDWI using an intraoperative MR scanner of low magnetic field strength (0.3 Tesla) has been developed. For image acquisition, a specially designed solenoid radiofrequency receiver coil integrated with a modified Sugita head holder (head-holder coil) was used. While the sensitivity characteristics of the head-holder coil were found to be 29% lower compared to a diagnostic quadrature head coil, they were sufficient to obtain iDWI images of good quality. The relationship between the angle of the motion probe gradient (MPG) pulse to the vertical axis and pyramidal tract contrasting were examined in 4 healthy men with a mean age of 30 ± 5.7 years. The contrast ratio reached a maximum when the MPG pulse was applied exactly in the anteroposterior direction. The difference of the contrast ratio between right and left sides was not statistically significant. Pyramidal tract visualization became worse and the contrast ratio was reduced when the MPG pulse was applied at different angles to the vertical axis; the reduction rate varied from 20.1 to 27.9% for each 15 degrees of rotation irrespective of its side. In conclusion, the developed scanning protocol for iDWI using an originally designed head-holder coil allowed effective visualization of the pyramidal tracts using an intraoperative MR scanner of low magnetic field strength.

Original languageEnglish
Pages (from-to)63-66
Number of pages4
JournalMinimally Invasive Neurosurgery
Volume51
Issue number2
DOIs
Publication statusPublished - 2008 Apr
Externally publishedYes

Fingerprint

Pyramidal Tracts
Head
Magnetic Fields
Neuronavigation
Brain

Keywords

  • Diffusion-weighted imaging
  • Intraoperative MRI
  • Intraoperative neuronavigation
  • Pyramidal tract

ASJC Scopus subject areas

  • Clinical Neurology

Cite this

Intraoperative diffusion-weighted imaging for visualization of the pyramidal tracts. Part I : Pre-clinical validation of the scanning protocol. / Ozawa, N.; Muragaki, Y.; Nakamura, R.; Iseki, Hiroshi.

In: Minimally Invasive Neurosurgery, Vol. 51, No. 2, 04.2008, p. 63-66.

Research output: Contribution to journalArticle

@article{dfd8e919f3b14a5286d54ff2df70a564,
title = "Intraoperative diffusion-weighted imaging for visualization of the pyramidal tracts. Part I: Pre-clinical validation of the scanning protocol",
abstract = "Integration of intraoperative diffusion-weighted imaging (iDWI) into neuronavigation can be potentially useful for identification of the pyramidal tract during surgery for parenchymal brain lesions. The technique of iDWI using an intraoperative MR scanner of low magnetic field strength (0.3 Tesla) has been developed. For image acquisition, a specially designed solenoid radiofrequency receiver coil integrated with a modified Sugita head holder (head-holder coil) was used. While the sensitivity characteristics of the head-holder coil were found to be 29{\%} lower compared to a diagnostic quadrature head coil, they were sufficient to obtain iDWI images of good quality. The relationship between the angle of the motion probe gradient (MPG) pulse to the vertical axis and pyramidal tract contrasting were examined in 4 healthy men with a mean age of 30 ± 5.7 years. The contrast ratio reached a maximum when the MPG pulse was applied exactly in the anteroposterior direction. The difference of the contrast ratio between right and left sides was not statistically significant. Pyramidal tract visualization became worse and the contrast ratio was reduced when the MPG pulse was applied at different angles to the vertical axis; the reduction rate varied from 20.1 to 27.9{\%} for each 15 degrees of rotation irrespective of its side. In conclusion, the developed scanning protocol for iDWI using an originally designed head-holder coil allowed effective visualization of the pyramidal tracts using an intraoperative MR scanner of low magnetic field strength.",
keywords = "Diffusion-weighted imaging, Intraoperative MRI, Intraoperative neuronavigation, Pyramidal tract",
author = "N. Ozawa and Y. Muragaki and R. Nakamura and Hiroshi Iseki",
year = "2008",
month = "4",
doi = "10.1055/s-2007-1004557",
language = "English",
volume = "51",
pages = "63--66",
journal = "Minimally Invasive Neurosurgery",
issn = "0946-7211",
publisher = "Georg Thieme Verlag",
number = "2",

}

TY - JOUR

T1 - Intraoperative diffusion-weighted imaging for visualization of the pyramidal tracts. Part I

T2 - Pre-clinical validation of the scanning protocol

AU - Ozawa, N.

AU - Muragaki, Y.

AU - Nakamura, R.

AU - Iseki, Hiroshi

PY - 2008/4

Y1 - 2008/4

N2 - Integration of intraoperative diffusion-weighted imaging (iDWI) into neuronavigation can be potentially useful for identification of the pyramidal tract during surgery for parenchymal brain lesions. The technique of iDWI using an intraoperative MR scanner of low magnetic field strength (0.3 Tesla) has been developed. For image acquisition, a specially designed solenoid radiofrequency receiver coil integrated with a modified Sugita head holder (head-holder coil) was used. While the sensitivity characteristics of the head-holder coil were found to be 29% lower compared to a diagnostic quadrature head coil, they were sufficient to obtain iDWI images of good quality. The relationship between the angle of the motion probe gradient (MPG) pulse to the vertical axis and pyramidal tract contrasting were examined in 4 healthy men with a mean age of 30 ± 5.7 years. The contrast ratio reached a maximum when the MPG pulse was applied exactly in the anteroposterior direction. The difference of the contrast ratio between right and left sides was not statistically significant. Pyramidal tract visualization became worse and the contrast ratio was reduced when the MPG pulse was applied at different angles to the vertical axis; the reduction rate varied from 20.1 to 27.9% for each 15 degrees of rotation irrespective of its side. In conclusion, the developed scanning protocol for iDWI using an originally designed head-holder coil allowed effective visualization of the pyramidal tracts using an intraoperative MR scanner of low magnetic field strength.

AB - Integration of intraoperative diffusion-weighted imaging (iDWI) into neuronavigation can be potentially useful for identification of the pyramidal tract during surgery for parenchymal brain lesions. The technique of iDWI using an intraoperative MR scanner of low magnetic field strength (0.3 Tesla) has been developed. For image acquisition, a specially designed solenoid radiofrequency receiver coil integrated with a modified Sugita head holder (head-holder coil) was used. While the sensitivity characteristics of the head-holder coil were found to be 29% lower compared to a diagnostic quadrature head coil, they were sufficient to obtain iDWI images of good quality. The relationship between the angle of the motion probe gradient (MPG) pulse to the vertical axis and pyramidal tract contrasting were examined in 4 healthy men with a mean age of 30 ± 5.7 years. The contrast ratio reached a maximum when the MPG pulse was applied exactly in the anteroposterior direction. The difference of the contrast ratio between right and left sides was not statistically significant. Pyramidal tract visualization became worse and the contrast ratio was reduced when the MPG pulse was applied at different angles to the vertical axis; the reduction rate varied from 20.1 to 27.9% for each 15 degrees of rotation irrespective of its side. In conclusion, the developed scanning protocol for iDWI using an originally designed head-holder coil allowed effective visualization of the pyramidal tracts using an intraoperative MR scanner of low magnetic field strength.

KW - Diffusion-weighted imaging

KW - Intraoperative MRI

KW - Intraoperative neuronavigation

KW - Pyramidal tract

UR - http://www.scopus.com/inward/record.url?scp=42549147551&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=42549147551&partnerID=8YFLogxK

U2 - 10.1055/s-2007-1004557

DO - 10.1055/s-2007-1004557

M3 - Article

VL - 51

SP - 63

EP - 66

JO - Minimally Invasive Neurosurgery

JF - Minimally Invasive Neurosurgery

SN - 0946-7211

IS - 2

ER -