Minim Invasive Neurosurg 2008; 51(2): 67-71
DOI: 10.1055/s-2007-1004558
Original Article

© Georg Thieme Verlag KG Stuttgart · New York

Intraoperative Diffusion-Weighted Imaging for Visualization of the Pyramidal Tracts. Part II: Clinical Study of Usefulness and Efficacy

N. Ozawa 1 , 4 , Y. Muragaki 1 , 2 , R. Nakamura 1 , 3 , H. lseki 1 , 2 , 3
  • 1Faculty of Advanced Techno-Surgery, Institute of Advanced Biomedical Engineering and Science, Tokyo Women's Medical University, Tokyo, Japan
  • 2Department of Neurosurgery, Neurological Institute, Tokyo Women's Medical University, Tokyo, Japan
  • 3International Research and Educational Institute for Integrated Medical Sciences (IREIIMS), Tokyo Women's Medical University, Tokyo, Japan
  • 4MRI System division, Hitachi Medical Corporation, Chiba, Japan
Further Information

Publication History

Publication Date:
09 April 2008 (online)

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Abstract

Precise identification and preservation of the pyramidal tract during surgery for parenchymal brain tumors is of crucial importance for the avoidance of postoperative deterioration of the motor function. The technique of intraoperative diffusion-weighted imaging (iDWI) using an intraoperative MR scanner of low magnetic field strength (0.3 Tesla) has been developed. Its clinical usefulness and efficacy were evaluated in 10 surgically treated patients with gliomas (5 men and 5 women, mean age: 41.2±13.9 years). iDWI permitted visualization of the pyramidal tract on the non-affected side in all 10 cases, and on the affected side in 8 cases. Motion artifacts were observed in four patients, but were not an obstacle to identification of the pyramidal tract. Good correspondence of the anatomical landmarks localization on iDWI and T1-weighted imaging was found. All participating neurosurgeons agreed that, in the majority of cases, iDWI was very useful for localization of the pyramidal tract and for clarification of its spatial relationships with the tumor. In conclusion, image quality and accuracy of the iDWI obtained with an MR scanner of low magnetic field strength (0.3 Tesla) are sufficient for possible incorporation into an intraoperative neuronavigation system. The use of iDWI in addition to structural iMRl and subcortical functional mapping with electrical stimulation can potentially result in a reduction of the postoperative morbidity after aggressive surgical removal of lesions located in the vicinity to the motor white matter tracts.