Abstracts

THE USEFULNESS OF MEP MONITORING IN THE IMAGE-GUIDED AND COMPUTER-ASSISTED OPERATION OF THE CEREBRAL LESIONS AROUND THE CENTRAL SULCUS

Abstract number : 3.294
Submission category :
Year : 2002
Submission ID : 75
Source : www.aesnet.org
Presentation date : 12/7/2002 12:00:00 AM
Published date : Dec 1, 2002, 06:00 AM

Authors :
Yasukazu Kajita, Satoshi Maesawa, Otone Endoh, Toshihiko Wakabayashi, Jun Yoshida. Neurosurgery, Nagoya University, Postgraduate School of Medicine, Nagoya, Aichi, Japan

RATIONALE: Surgery for resection of the lesions around the central sulcus carries an associated risk of causing significant motor deficits. The use of motor evoked potential (MEP) monitoring in the image-guided and computer-assisted operation allows these lesions to be removed with maximal safety and efficacy.
METHODS: In thirty patients with cerebral lesions adjacent to the central lesions, the surgical resection was performed. We oriented the lesion site anatomically using the neuronavigation. It was oriented through the scalp within 2 mm error and skin incision was designed. After craniotomy, central sulcus was determined by N20 phase reversal on sensory evoked potential (SEP) recording following the median nerve stimulation. Cortical motor mapping was performed by monopolar anodal stimulation with a train of 500Hz (3-5 pulses) (stimulation intensity 8-25 mA). Action potentials were recorded from facial, thenar, biceps arm and quadriceps femoralis muscles. Following the mapping procedure, MEP recording continued for the intra-operative monitoring of the motor system until radical lesion resection was macroscopically achieved. Intra-operative CT was taken to confirm the radical lesion resection using a mobile CT.
RESULTS: No new postoperative motor deficits were seen in 93% of the patients in this series.
CONCLUSIONS: This combination of intra-operative imaging, neuronavigation and MEP monitoring enhanced the safety of the operation of lesion resection around the central sulcus.