Continuous Facial Nerve Stimulating Burr for Otologic Surgeries

Bernardeschi, Danièle; Meskine, N.; Otaibi, Naif Al; Ablonczy, Reka; Kalamaridès, Michel; Grayeli, Alexis Bozorg; Sterkers, Olivier

doi:10.1097/mao.0b013e31822ec097

Cited by 26 publications

(20 citation statements)

References 16 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…In fact, the analysis of the effect of lateral distance shows that a drill path heading directly toward the FN is less likely to elicit an early response than a more lateral path. These results contrast previously published findings where the same NM enabled drill system was used to detect the FN during schwannoma removal (17). In that work, the FN was detected before penetration of the fallopian canal FIG.…”

Section: Discussioncontrasting

confidence: 56%

“…Previously, Bernardeschi et al (17) attempted to determine a correlation between distance to the FN and stimulation intensity during a translabyrinthine approach for vestibular schwannoma removal. Measurements were obtained by stopping the milling process at the first warning from the NM system and subsequent visual inspection of the remaining fallopian canal wall bone thickness in postoperative CT images.…”

mentioning

confidence: 99%

See 1 more Smart Citation

Feasibility of Using EMG for Early Detection of the Facial Nerve During Robotic Direct Cochlear Access

Ansó

Stahl²,

Gerber³

et al. 2014

Otology &Amp; Neurotology

View full text Add to dashboard Cite

Hypothesis: Facial nerve monitoring can be used synchronous with a high-precision robotic tool as a functional warning to prevent of a collision of the drill bit with the facial nerve during direct cochlear access (DCA). Background: Minimally invasive direct cochlear access (DCA) aims to eliminate the need for a mastoidectomy by drilling a small tunnel through the facial recess to the cochlea with the aid of stereotactic tool guidance. Because the procedure is performed in a blind manner, structures such as the facial nerve are at risk. Neuromonitoring is a commonly used tool to help surgeons identify the facial nerve (FN) during routine surgical procedures in the mastoid. Recently, neuromonitoring technology was integrated into a commercially available drill system enabling real-time monitoring of the FN. The objective of this study was to determine if this drilling system could be used to warn of an impending collision with the FN during robot-assisted DCA. Materials and Methods: The sheep was chosen as a suitable model for this study because of its similarity to the human ear anatomy. The same surgical workflow applicable to human patients was performed in the animal model. Bone screws, serving as reference fiducials, were placed in the skull near the ear canal. The sheep head was imaged using a computed tomographic scanner and segmentation of FN, mastoid, and other relevant structures as well as planning of drilling trajectories was carried out using a dedicated software tool. During the actual procedure, a surgical drill system was connected to a nerve monitor and guided by a custom built robot system. As the planned trajectories were drilled, stimulation and EMG response signals were recorded. A postoperative analysis was achieved after each surgery to determine the actual drilled positions. Results: Using the calibrated pose synchronized with the EMG signals, the precise relationship between distance to FN and EMG with 3 different stimulation intensities could be determined for 11 different tunnels drilled in 3 different subjects. Conclusion: From the results, it was determined that the current implementation of the neuromonitoring system lacks sensitivity and repeatability necessary to be used as a warning device in robotic DCA. We hypothesize that this is primarily because of the stimulation pattern achieved using a noninsulated drill as a stimulating probe. Further work is necessary to determine whether specific changes to the design can improve the sensitivity and specificity. Key Words: Cochlear implantVFacial nerveV MastoidectomyVNeuromonitor.Otol Neurotol 35:545Y554, 2014.Today, cochlear implantation procedures are performed much the same as when the implants were first introduced more than 3 decades ago, namely, through a mastoidectomy. Several research efforts have sought to reduce the invasiveness of the implantation procedure by avoiding the mastoidectomy (1,2), but questions of safety and other complications, such as electrode extrusion and undesirable insertion angles, have limited the accept...

show abstract

Section: Discussioncontrasting

confidence: 56%

mentioning

confidence: 99%

Feasibility of Using EMG for Early Detection of the Facial Nerve During Robotic Direct Cochlear Access

Ansó

Stahl²,

Gerber³

et al. 2014

Otology &Amp; Neurotology

View full text Add to dashboard Cite

show abstract

“…The stimulating burr allows performing intraoperative monitoring of the facial nerve throughout the entire surgery (16)(17)(18). This system is safe and simple, and saves time during middle and inner ear surgery (18).…”

Section: @ C I C E D I Z I O N I I N T E R N a Z I O N A L Imentioning

confidence: 99%

“…D. Bernardeschi and his team studied patients with acoustic nerve neuroma with the Nerve Integrity Monitor (Nim-3.0) system, which provides for continuous facial nerve stimulation with a burr (StimBurGard). In their paper, they recommended using 1 mA to drill safely near the facial nerve through translabyrinthine approach (18).…”

mentioning

confidence: 99%

Intraoperative identification of the facial nerve by needle electromyography stimulation with a burr

Khamgushkeeva¹,

Anikin²,

Aa³

2016

Gchir

View full text Add to dashboard Cite

Despite the existing possibilities of using modern surgical equipment and modern diagnostic techniques, there is still a risk of damaging the facial nerve during otological surgery (1,2). This is caused by the anatomic proximity of the facial nerve to the structures of the middle and inner ear (3-5). The facial nerve becomes more vulnerable to injury during repeated (sanifying) surgery on the middle ear, with the presence of dehiscence in the Fallopian canal, during the removal of masses in the middle ear (2,6), in cases of malformation of the middle or inner ear (7,8).Many scientific works study the anatomy of the facial nerve (3-5). Most of them provide a general description of the microtopographic characteristics of the facial canal and, at the same time, lack information on the thickness of its bone walls.Intraoperative damage causes paresis (paralysis) of the facial muscles, which leads to a degradation of the patients' quality of life. According to literary sources, during original surgery, the risk of dysfunction of the facial nerve is 0.6-3.7% of cases (9, 10). During repeated invasive surgery, the risk rises up to 4-10% of cases (1,11,12).The appearance of intraoperative facial nerve monitoring allowed identifying the nerve throughout the entire surgery (13-15), since this method of studying the neuromuscular system registers fluctuation of the electric potential of muscles in response to nerve stimulation.Despite considerable success in the development of machines for intraoperative monitoring of the facial nerve, the most important restriction remained, which was related to the fact that the system could not warn surgeons if they were operating near the facial nerve, whi-

show abstract

“…The approach results in the drilling tool passing within close proximity (0.1-1.2 mm [6,12]) of the facial nerve (FN), placing this vital structure at risk from either excessive drilling temperature or mechanical destruction by collision with the drill bit. Although electromyogram (EMG)-based neuromonitoring has become a standard safety mechanism for identification and preservation of the FN in middle ear surgeries, such as revision cases and cochlear implantations (13)(14)(15)(16)(17)(18)(19)(20)(21), it has yet to achieve the sensitivity and specificity required to become a reliable safety mechanism when operating in close vicinity of the FN (<0.3 mm), without line of sight to the surrounding anatomy.…”

mentioning

confidence: 99%

A Neuromonitoring Approach to Facial Nerve Preservation During Image-guided Robotic Cochlear Implantation

Ansó

Dür

Gavaghan

et al. 2016

Otology &Amp; Neurotology

View full text Add to dashboard Cite

Hypothesis: A multielectrode probe in combination with an optimized stimulation protocol could provide sufficient sensitivity and specificity to act as an effective safety mechanism for preservation of the facial nerve in case of an unsafe drill distance during image-guided cochlear implantation. Background: A minimally invasive cochlear implantation is enabled by image-guided and robotic-assisted drilling of an access tunnel to the middle ear cavity. The approach requires the drill to pass at distances below 1 mm from the facial nerve and thus safety mechanisms for protecting this critical structure are required. Neuromonitoring is currently used to determine facial nerve proximity in mastoidectomy but lacks sensitivity and specificity necessaries to effectively distinguish the close distance ranges experienced in the minimally invasive approach, possibly because of current shunting of uninsulated stimulating drilling tools in the drill tunnel and because of nonoptimized stimulation parameters. To this end, we propose an advanced neuromonitoring approach using varying levels of stimulation parameters together with an integrated bipolar and monopolar stimulating probe. Materials and Methods: An in vivo study (sheep model) was conducted in which measurements at specifically planned and navigated lateral distances from the facial nerve were performed to determine if specific sets of stimulation parameters in combination with the proposed neuromonitoring system could reliably detect an imminent collision with the facial nerve. For the accurate positioning of the neuromonitoring probe, a dedicated robotic system for image-guided cochlear implantation was used and drilling accuracy was corrected on postoperative microcomputed tomographic images. Results: From 29 trajectories analyzed in five different subjects, a correlation between stimulus threshold and drillto-facial nerve distance was found in trajectories colliding with the facial nerve (distance <0.1 mm). The shortest pulse duration that provided the highest linear correlation between stimulation intensity and drill-to-facial nerve distance was 250 ms. Only at low stimulus intensity values ( 0.3 mA) and with the bipolar configurations of the probe did the neuromonitoring system enable sufficient lateral specificity (>95%) at distances to the facial nerve below 0.5 mm. However, reduction in stimulus threshold to 0.3 mA or lower resulted in a decrease of facial nerve distance detection range below 0.1 mm (>95% sensitivity). Subsequent histopathology follow-up of three representative cases where the neuromonitoring system could reliably detect a collision with the facial nerve (distance <0.1 mm) revealed either mild or inexistent damage to the nerve fascicles. Conclusion: Our findings suggest that although no general correlation between facial nerve distance and stimulation threshold existed, possibly because of variances in patient-specific anatomy, correlations at very close distances to the facial nerve and high levels of specificity would enable a binary respo...

show abstract

Continuous Facial Nerve Stimulating Burr for Otologic Surgeries

Abstract: Continuous FN stimulating burr by means of the StimBurGard system is a safe and effective tool for FN stimulation and identification. The integrity of FC is preserved in most cases when the stimulation intensity is 1 mA.

Cited by 26 publications

References 16 publications

Feasibility of Using EMG for Early Detection of the Facial Nerve During Robotic Direct Cochlear Access

Feasibility of Using EMG for Early Detection of the Facial Nerve During Robotic Direct Cochlear Access

Intraoperative identification of the facial nerve by needle electromyography stimulation with a burr

A Neuromonitoring Approach to Facial Nerve Preservation During Image-guided Robotic Cochlear Implantation

Contact Info

Product

Resources

About