Abstract: Intraoperative mapping and monitoring techniques
for eloquent area tumors are routinely used world
wide. Very few data are available regarding mapping and
monitoring methods and preferences, intraoperative seizures
occurrence and perioperative antiepileptic drug
management. A questionnaire was sent to 20 European centers with experience in intraoperative mapping or neurophysiological
monitoring for the treatment of eloquent
area tumors. Fifteen centers returned the completed questionnaires.
Data was available on 2098 patients. 863 patients
(41.1%) were operated on through awake surgery
and intraoperative mapping, while 1235 patients (58.8%)
received asleep surgery and intraoperative electrophysiological
monitoring or mapping. There was great heterogeneity
between centers with some totally AW oriented (up
to 100%) and other almost totally ASL oriented (up to
92%) (31% SD). For awake surgery, 79.9% centers preferred
an asleep-awake-asleep anesthesia protocol. Only
53.3% of the centers used ECoG or transcutaneous EEG.
The incidence of intraoperative seizures varied significantly
between centers, ranging from 2.5% to 54% (p <
0.001). It there appears to be a statistically significant link
between the mastery of mapping technique and the risk of
intraoperative seizures. Moreover, history of preoperative
seizures can significantly increase the risk of intraoperative
seizures (p < 0.001). Intraoperative seizures occurrence
was similar in patients with or without perioperative
drugs (12% vs. 12%, p = 0.2). This is the first European
survey to assess intraoperative functional mapping and
monitoring protocols and the management of peri- and
intraoperative seizures. This data can help identify specific
aspects that need to be investigated in prospective and
controlled studies.
