TY - JOUR
T1 - Transcranial Motor Evoked Potentials during Basilar Artery Aneurysm Surgery
T2 - Technique Application for 30 Consecutive Patients
AU - Quiñones-Hinojosa, Alfredo
AU - Alam, Mirza
AU - Lyon, Russ
AU - Yingling, Charles D.
AU - Lawton, Michael T.
AU - Klopfenstein, Jeffrey D.
AU - Spetzler, Robert F.
AU - Kelly, Patrick J.
AU - Solomon, Robert A.
PY - 2004/4
Y1 - 2004/4
N2 - OBJECTIVE: Microsurgical clipping of basilar artery aneurysms carries a risk of neurological compromise resulting from midbrain or thalamic ischemia. Somatosensory evoked potential (SSEP) monitoring and electroencephalography are the standard techniques for assessing the level of cerebroprotective anesthesia and monitoring ischemia during temporary occlusion or after permanent clipping. Transcranial motor evoked potential (TcMEP) monitoring was added to determine whether this modality improved intraoperative monitoring. METHODS: Combined SSEP/electroencephalographic/TcMEP monitoring was used for 30 consecutive patients with basilar artery apex aneurysms in the past 1.5 years. Voltage thresholds were recorded before, during, and after aneurysm treatment for the last 10 patients. RESULTS: All 30 patients underwent an orbitozygomatic craniotomy for clipping (28 patients), wrapping (1 patient), or superficial temporal artery-superior cerebellar artery bypass (1 patient). Electrophysiological changes occurred for 10 patients (33%), elicited by temporary clipping (6 patients), permanent clipping (3 patients), or retraction (1 patient). Isolated SSEP changes were observed for one patient, isolated TcMEP changes for five patients, and changes in both TcMEPs and SSEPs for four patients. Among patients with simultaneous changes, TcMEP abnormalities were more robust and occurred earlier than SSEP abnormalities. Impaired motor conduction was detected first with an increase in the voltage threshold (from 206 ± 22 to 410 ± 49 V, P < 0.05, n = 3) and then with loss of TcMEP responses. SSEP and TcMEP signals returned to baseline values for all patients after corrective measures were taken. CONCLUSION: TcMEP monitoring can be safely and easily added to traditional neurophysiological monitoring during basilar artery aneurysm surgery. These results suggest that TcMEPs may be more sensitive than SSEPs to basilar artery and perforating artery ischemia. This additional intraoperative information might minimize the incidence of ischemic complications attributable to prolonged temporary occlusion or inadvertent perforator occlusion.
AB - OBJECTIVE: Microsurgical clipping of basilar artery aneurysms carries a risk of neurological compromise resulting from midbrain or thalamic ischemia. Somatosensory evoked potential (SSEP) monitoring and electroencephalography are the standard techniques for assessing the level of cerebroprotective anesthesia and monitoring ischemia during temporary occlusion or after permanent clipping. Transcranial motor evoked potential (TcMEP) monitoring was added to determine whether this modality improved intraoperative monitoring. METHODS: Combined SSEP/electroencephalographic/TcMEP monitoring was used for 30 consecutive patients with basilar artery apex aneurysms in the past 1.5 years. Voltage thresholds were recorded before, during, and after aneurysm treatment for the last 10 patients. RESULTS: All 30 patients underwent an orbitozygomatic craniotomy for clipping (28 patients), wrapping (1 patient), or superficial temporal artery-superior cerebellar artery bypass (1 patient). Electrophysiological changes occurred for 10 patients (33%), elicited by temporary clipping (6 patients), permanent clipping (3 patients), or retraction (1 patient). Isolated SSEP changes were observed for one patient, isolated TcMEP changes for five patients, and changes in both TcMEPs and SSEPs for four patients. Among patients with simultaneous changes, TcMEP abnormalities were more robust and occurred earlier than SSEP abnormalities. Impaired motor conduction was detected first with an increase in the voltage threshold (from 206 ± 22 to 410 ± 49 V, P < 0.05, n = 3) and then with loss of TcMEP responses. SSEP and TcMEP signals returned to baseline values for all patients after corrective measures were taken. CONCLUSION: TcMEP monitoring can be safely and easily added to traditional neurophysiological monitoring during basilar artery aneurysm surgery. These results suggest that TcMEPs may be more sensitive than SSEPs to basilar artery and perforating artery ischemia. This additional intraoperative information might minimize the incidence of ischemic complications attributable to prolonged temporary occlusion or inadvertent perforator occlusion.
KW - Aneurysm
KW - Basilar artery
KW - Motor evoked potential
KW - Neuromonitoring
KW - Somatosensory evoked potential
KW - Subarachnoid hemorrhage
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UR - http://www.scopus.com/inward/citedby.url?scp=1842430862&partnerID=8YFLogxK
U2 - 10.1227/01.NEU.0000114511.33035.AF
DO - 10.1227/01.NEU.0000114511.33035.AF
M3 - Article
C2 - 15046658
AN - SCOPUS:1842430862
SN - 0148-396X
VL - 54
SP - 916
EP - 924
JO - Neurosurgery
JF - Neurosurgery
IS - 4
ER -