Volumetric assessment of glioma removal by intraoperative high-field magnetic resonance imaging.
OBJECTIVE
To investigate the contribution of high-field intraoperative magnetic resonance imaging (iMRI) for further reduction of tumor volume in glioma surgery.


METHODS
From April 2002 to June 2003, 182 neurosurgical procedures were performed with a 1.5-T magnetic resonance system. Among patients who underwent these procedures, 47 patients with gliomas (14 with World Health Organization Grade I or II glioma, and 33 with World Health Organization Grade III or IV glioma) who underwent craniotomy were investigated retrospectively. Completeness of tumor resection and volumetric analysis were assessed with intraoperative imaging data.


RESULTS
Surgical procedures were influenced by iMRI in 36.2% of operations, and surgery was continued to remove residual tumor. Additional further resection significantly reduced the percentage of final tumor volume compared with first iMRI scan (6.9% +/- 10.3% versus 21.4% +/- 13.8%; P < 0.001). Percentages of final tumor volume also were significantly reduced in both low-grade (10.3% +/- 11.5% versus 25.8% +/- 16.3%; P < 0.05) and high-grade gliomas (5.4% +/- 9.9% versus 19.5% +/- 13.0%; P < 0.001). Complete resection was achieved finally in 36.2% of all patients (low-grade, 57.1%; high-grade, 27.3%). Among the 17 patients in whom complete tumor resection was achieved, 7 complete resections (41.2%) were attributable to further tumor removal after iMRI. We did not encounter unexpected events attributable to high-field iMRI, and standard neurosurgical equipment could be used safely.


CONCLUSIONS
Despite extended resections, introduction of high-field iMRI in conjunction with functional navigation did not translate into an increased risk of postoperative deficits. The use of high-field iMRI increased radicality in glioma surgery without additional morbidity.
Department of Neurosurgery, University Erlangen-Nürnberg, Erlangen, Germany. nimsky@nch.imed.uni-erlangen.de
Christopher
C
Nimsky
Atsushi
A
Fujita
Oliver
O
Ganslandt
Boris
B
Von Keller
Rudolf
R
Fahlbusch
D000293:Adolescent; D000328:Adult; D000368:Aged; D001932:Brain Neoplasms / Q000145:classification / Q000175:diagnosis / Q000601:surgery*; D002648:Child; D003399:Craniotomy / Q000295:instrumentation; D004867:Equipment Design; D005260:Female; D005910:Glioma / Q000145:classification / Q000175:diagnosis / Q000601:surgery*; D006801:Humans; D007089:Image Enhancement / Q000295:instrumentation*; D007091:Image Processing, Computer-Assisted / Q000295:instrumentation*; D021621:Imaging, Three-Dimensional / Q000295:instrumentation*; D007431:Intraoperative Complications / Q000175:diagnosis / Q000601:surgery*; D008279:Magnetic Resonance Imaging / Q000295:instrumentation*; D008297:Male; D008432:Mathematical Computing; D008866:Microsurgery / Q000295:instrumentation*; D008875:Middle Aged; D018365:Neoplasm, Residual / Q000175:diagnosis / Q000601:surgery*; D009460:Neurologic Examination; D038361:Neuronavigation / Q000295:instrumentation*; D011183:Postoperative Complications / Q000175:diagnosis; D012189:Retrospective Studies; D012984:Software