Localized Transcranial Electrical Motor Evoked Potentials for Monitoring Cranial Nerves in Cranial Base Surgery

Akagami, Ryojo; Dong, Charles; Westerberg, Brian D.

doi:10.1227/01.neu.0000163486.93702.95

Cited by 68 publications

(85 citation statements)

References 19 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…13 More recently, the indication for MEP monitoring has been extended to also monitor the function of the corticobulbar tract, and, in particular, facial nerve function. 4,7 Most authors consider a reduction in FNMEP response amplitude of more than 50% as a warning criterion [1][2][3][4]7,8,12 as widely accepted for MEPs in supratentorial surgery. 15,19 The threshold-level method was first proposed for monitoring spinal cord function.…”

Section: The "Threshold-level" Methods For Fnmep Interpretationmentioning

confidence: 99%

“…4,7 Fa cial nerve MEPs allow activation of the motor pathway proximal to the surgical field by TES of the motor cortex and recording of responses in facial nerve target muscles. With this technique, facial nerve function can be monitored continuously.…”

mentioning

confidence: 99%

“…Most authors use the decrease in FNMEP response amplitude as a warning criterion. [1][2][3][4]8,12 However, FNMEP responses have inherent variability and are hard to quantify. Also, high FNMEP stimulation intensity is needed to achieve maximal FNMEP response already at baseline so that subsequent response deterioration can be assessed.…”

mentioning

confidence: 99%

See 2 more Smart Citations

Facial nerve motor evoked potentials during skull base surgery to monitor facial nerve function using the threshold-level method

Sarnthein

Hejrati

Neidert

et al. 2013

FOC

View full text Add to dashboard Cite

Object During surgeries that put the facial nerve at risk for injury, its function can be continuously monitored by transcranial facial nerve motor evoked potentials (FNMEPs) in facial nerve target muscles. Despite their advantages, FNMEPs are not yet widely used. While most authors use a 50% reduction in FNMEP response amplitudes as a warning criterion, in this paper the authors' approach was to keep the response amplitude constant by increasing the stimulation intensity and to establish a warning criterion based on the “threshold-level” method. Methods The authors included 34 consecutive procedures involving 33 adult patients (median age 47 years) in whom FNMEPs were monitored. A threshold increase greater than 20 mA for eliciting FNMEPs in the most reliable facial nerve target muscle was considered a prediction of reduced postoperative facial nerve function, and subsequently a warning was issued to the surgeon. Preoperative and early postoperative function was documented using the House-Brackmann grading system. Results Monitoring of FNMEPs was feasible in all 34 surgeries in at least one facial nerve target muscle. The mentalis muscle yielded the best results. The House-Brackmann grade deteriorated in 17 (50%) of 34 cases. The warning criterion was reached in 18 (53%) of 34 cases, which predicted an 83% risk of House-Brackmann grade deterioration. Sensitivity amounted to 88% (CI 64%–99%) and specificity to 82% (CI 57%–96%). Deterioration of FNMEPs and a worse House-Brackmann grade showed a high degree of association (p < 0.001). The impact of FNMEP monitoring on surgical strategy is exemplified in an illustrative case. Conclusions In surgeries that put the facial nerve at risk, the intraoperative increase in FNMEP stimulation threshold was closely correlated to postoperative facial nerve dysfunction. Monitoring of FNMEPs is a valid indicator of facial nerve function in skull base surgery. It should be used as an adjunct to direct electrical facial nerve stimulation and continuous electromyographic monitoring of facial nerve target muscles.

show abstract

Section: The "Threshold-level" Methods For Fnmep Interpretationmentioning

confidence: 99%

mentioning

confidence: 99%

See 1 more Smart Citation

Facial nerve motor evoked potentials during skull base surgery to monitor facial nerve function using the threshold-level method

Sarnthein

Hejrati

Neidert

et al. 2013

FOC

View full text Add to dashboard Cite

show abstract

“…Although optimal stimulation parameters for TCMEP of the FN remain unknown, current data support previously published techniques using multipulse stimulation of 3 to 5 trains, duration 0.2 to 0.5 milliseconds, and interstimulus interval of 4 milliseconds. [20][21][22]24 These parameters successfully minimized peripheral FN activation yet were able to overcome anesthesia-induced suppression of MEP. In addition to stimulation parameters, many factors are known to affect TCMEP monitoring, including anesthesia, use of muscle relaxants, number and type of recording electrodes, and individual patient variation.…”

Section: Discussionmentioning

confidence: 99%

“…[20][21][22][23][24][25][26] Studies indicate that TCMEP of the facial nerve is feasible and may predict immediate postoperative outcome. Long-term functional data and the relationship between TCMEP and facial nerve function beyond the immediate postoperative period is lacking.…”

Section: -19mentioning

confidence: 99%

Intraoperative Transcranial Motor-Evoked Potential Monitoring of the Facial Nerve during Cerebellopontine Angle Tumor Resection

Cosetti¹,

Xu²,

Rivera³

et al. 2011

Skull Base

View full text Add to dashboard Cite

ICAR: endoscopic skull‐base surgery

Wang

Zanation

Gardner

et al. 2019

Int Forum Allergy Rhinol

157

279

View full text Add to dashboard Cite

Background Endoscopic skull‐base surgery (ESBS) is employed in the management of diverse skull‐base pathologies. Paralleling the increased utilization of ESBS, the literature in this field has expanded rapidly. However, the rarity of these diseases, the inherent challenges of surgical studies, and the continued learning curve in ESBS have resulted in significant variability in the quality of the literature. To consolidate and critically appraise the available literature, experts in skull‐base surgery have produced the International Consensus Statement on Endoscopic Skull‐Base Surgery (ICAR:ESBS). Methods Using previously described methodology, topics spanning the breadth of ESBS were identified and assigned a literature review, evidence‐based review or evidence‐based review with recommendations format. Subsequently, each topic was written and then reviewed by skull‐base surgeons in both neurosurgery and otolaryngology. Following this iterative review process, the ICAR:ESBS document was synthesized and reviewed by all authors for consensus. Results The ICAR:ESBS document addresses the role of ESBS in primary cerebrospinal fluid (CSF) rhinorrhea, intradural tumors, benign skull‐base and orbital pathology, sinonasal malignancies, and clival lesions. Additionally, specific challenges in ESBS including endoscopic reconstruction and complication management were evaluated. Conclusion A critical review of the literature in ESBS demonstrates at least the equivalency of ESBS with alternative approaches in pathologies such as CSF rhinorrhea and pituitary adenoma as well as improved reconstructive techniques in reducing CSF leaks. Evidence‐based recommendations are limited in other pathologies and these significant knowledge gaps call upon the skull‐base community to embrace these opportunities and collaboratively address these shortcomings.

show abstract

Localized Transcranial Electrical Motor Evoked Potentials for Monitoring Cranial Nerves in Cranial Base Surgery

Abstract: Facial nerve MEPs recorded intraoperatively during cranial base surgery using the proposed technique predicts immediate postoperative facial nerve outcome. This technique can also be used to monitor other motor cranial nerves in cranial base surgery.

Cited by 68 publications

References 19 publications

Facial nerve motor evoked potentials during skull base surgery to monitor facial nerve function using the threshold-level method

Facial nerve motor evoked potentials during skull base surgery to monitor facial nerve function using the threshold-level method

Intraoperative Transcranial Motor-Evoked Potential Monitoring of the Facial Nerve during Cerebellopontine Angle Tumor Resection

ICAR: endoscopic skull‐base surgery

Contact Info

Product

Resources

About