New development in intraoperative video monitoring of facial nerve: a pilot study

Management of the facial nerve in parotid cancer: preservation or resection and reconstruction

PURPOSE

Management of the facial nerve is instrumental in the surgical treatment of parotid cancer.

METHODS

A literature search was conducted using PubMed and ScienceDirect database. A total of 195 articles were finally included into the analysis, based on relevance, scientific evidence and actuality.

RESULTS

In the majority of cases the facial nerve is not involved by tumor. In these cases, identification and preservation of the nerve, in addition to complete tumor removal, are essential for successful surgery. When the nerve is infiltrated by tumor, the affected portion of the nerve must be resected as part of radical parotidectomy. Primary nerve reconstruction or other reanimation techniques give the best long-term functional and cosmetic results. A comprehensive diagnostic evaluation with current imaging and electrophysiological studies will provide the surgeon with the best knowledge of the relationship of the facial nerve to the tumor. Several standardized methods are helpful in finding, dissecting and preserving the nerve during parotid cancer surgery. When radical parotidectomy is indicated, the initial diagnostic work-up can assist in defining the need for adjuvant postoperative therapy and facial reanimation. The aim of rehabilitation is to restore tone, symmetry, and movement to the paralyzed face.

CONCLUSIONS

The surgical management of facial paralysis has undergone many improvements in recent years. This review gives an overview of recent advances in the diagnostic work-up, surgical techniques and any necessary rehabilitation of the facial nerve in parotid cancer surgery.

A systematic recurrent theme analysis of the reported limitations of facial electromyography

Background

Advances in digital technology hold promise in expanding the clinical and consumer applications of facial electromyography (EMG) through thedevelopment of wireless pervasive systems capable of operating in a nonclinical environment. This systematic review aims to appraise the most commonly reported limitations of the technology in clinical research and practice.

Methods

A systematic search for clinical facial EMG literature was performed using MEDLINE, EMBASE, PsychINFO and CINAHL. No language limits were applied. Search results were screened using defined criteria by two authors with disagreements resolved by a third. Practical limitations in the technology, as reported by the authors, were recorded and characterised using recurrent theme analysis.

Results

A total of 4,983 records were identified. Of those, 1,061 articles met eligibility criteria and were subsequently reviewed. In the medical domain, the most common area of application was in psychosocial studies (28% of medical studies); in the surgical domain monitoring of facial nerve integrity was the most common application of facial electromyography (27% of surgical studies). Collectively, the three most commonly reported limitations were motion artefact (13.7%), inter-subject variability in response and anatomy (13.1%), and muscle crosstalk (12.0%).

Conclusions

This is the first study to evaluate the limitations of facial EMG using a systematic analysis of author reports. Highlighting technology limitations in this non-biased manner raises awareness to users key issues and reliably informs the development of future systems.

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The limitations of facial electromyography have been systematically reviewed.

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The respective limitations of surface and needle facial electromyography have been examined across both medical and surgical domains.

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Quantification of such limitations informs continued development of future systems.

Impaired overt facial mimicry in response to dynamic facial expressions in high-functioning autism spectrum disorders

Previous electromyographic studies have reported that individuals with autism spectrum disorders (ASD) exhibited atypical patterns of facial muscle activity in response to facial expression stimuli. However, whether such activity is expressed in visible facial mimicry remains unknown. To investigate this issue, we videotaped facial responses in high-functioning individuals with ASD and controls to dynamic and static facial expressions of anger and happiness. Visual coding of facial muscle activity and the subjective impression ratings showed reduced congruent responses to dynamic expressions in the ASD group. Additionally, this decline was related to social dysfunction. These results suggest that impairment in overt facial mimicry in response to others' dynamic facial expressions may underlie difficulties in reciprocal social interaction among individuals with ASD.

Intraoperative neuromonitoring techniques in the surgical management of acoustic neuromas

Unfavorable outcomes such as facial paralysis and deafness were once unfortunate probable complications following resection of acoustic neuromas. However, the implementation of intraoperative neuromonitoring during acoustic neuroma surgery has demonstrated placing more emphasis on quality of life and preserving neurological function. A modern review demonstrates a great degree of recent success in this regard. In facial nerve monitoring, the use of modern electromyography along with improvements in microneurosurgery has significantly improved preservation. Recent studies have evaluated the use of video monitoring as an adjunctive tool to further improve outcomes for patients undergoing surgery. Vestibulocochlear nerve monitoring has also been extensively studied, with the most popular techniques including brainstem auditory evoked potential monitoring, electrocochleography, and direct compound nerve action potential monitoring. Among them, direct recording remains the most promising and preferred monitoring method for functional acoustic preservation. However, when compared with postoperative facial nerve function, the hearing preservation is only maintained at a lower rate. Here, the authors analyze the major intraoperative neuromonitoring techniques available for acoustic neuroma resection.