Predictive value of postoperative electrophysiologic testing of the facial nerve after cerebellopontine angle surgery

Prognostic factors of facial nerve function after vestibular schwannoma removal via translabyrinthine approach

BACKGROUND

Prediction of facial function is a major concern when proposing surgery for patients with vestibular schwannoma (VS).

AIMS/OBJECTIVES

To evaluate postoperative facial function of patients who underwent operation of VS via a translabyrinthine approach (TL), and to analyze factors that influence facial functions.

MATERIAL AND METHODS

A total of 91 VS patients, who were operated via a TL approach, between March 1997 and December 2016, were analyzed. Demographics, tumor-related factors, and operative findings were collected. Facial function was assessed according to the House-Brackmann (HB) grading system before surgery, immediately after surgery, and 1-, 3-, 6-months, and 1 year after surgery.

RESULTS

In cases of patients that had a tumor that extended to the CPA, an unsatisfactory facial outcome was noted in 12 (30.0%) patients. FN outcomes after tumor removal depend on tumor size (p = .040). Among FN-related factors, only the FN recovery timing was correlated with facial outcomes (p = .030). Univariable and multivariable analysis revealed that tumor size and the timing of FN recovery were significant as favorable prognostic factors for good facial outcomes.

CONCLUSIONS AND SIGNIFICANCE

Tumor size and the FN recovery timing are significant prognostic factors of facial outcome in VS patients who underwent operations via a TL approach.

A Modified Pre-Auricular Approach in the Treatment of Orbital Zygomatic Maxillary Complex Fractures

OBJECTIVE

This study aimed to evaluate the safety of a modified pre-aricular approach in the treatment of orbital zygomatic maxillary complex fractures.

METHODS

This was a retrospective study of clinical data from 108 adults who were diagnosed with orbital zygomatic maxillary complex fractures and undergo open reduction and internal fixation through a modified pre-auricular approach. Exophthalmometry and limitation of extraocular muscle movement were determined using a Hertel exophthalmometer or synoptophore examination respectively. Primary complications were recorded, and postoperative facial nerve injury was tested by electrophysiologic analysis.

RESULTS

All patients received satisfied functional and cosmetic results at least 6 moths postoperatively. There were 2 cases (1.85%) involving complete or incomplete facial nerve injury confirmed by electrophysiologic analysis. The incidence of other postoperative complications including a hematoma rate of 1.85% patients and permanent hypesthesia or paresthesia in 2.78% of patients, and no cases of clinically significant temporal hollowing, alopecia, infection, or unacceptable scars encountered during a mean follow-up period of 2 years.

CONCLUSION

A modified pre-auricular approach with dissection deep to the temporalis fascia offers a safe and reliable surgical technique for accessing the malar arch in orbital zygomatic maxillary complex fractures.

Electromyographic and electroneurographic changes in internal nasal muscles after endonasal and external rhinoplasty

BACKGROUND

Anatomical structures of the nose (including muscles) are elevated, sutured, or reshaped during rhinoplasty. Electromyography and electroneurography are the objective electrophysiologic tests performed for the direct measurement of nasal muscle function.

OBJECTIVES

The authors investigate the predictive values and functional status of nasal muscles during voluntary facial and nasal movements following open and closed rhinoplasty.

METHODS

In 48 patients who underwent rhinoplasty, surface electrodes were placed to preoperatively and postoperatively measure nasal muscle function with electromyography and electroneurography. Results were analyzed according to whether the patient had undergone open or closed rhinoplasty.

RESULTS

Electroneurography amplitudes were decreased postoperatively on both sides, in both groups. This increase was statistically significant (p < .001). Electromyography-recorded amplitude of nasal muscle contraction tension significantly decreased postoperatively in response to all voluntary movements in two cases in the closed rhinoplasty group (6.6%) and in two cases in the open rhinoplasty group (11.1%). In essence, the activity strength of the nasal muscles decreased postoperatively for some patients. The mean differences between the two groups were not statistically significant (p = .280).

CONCLUSIONS

The data showed no meaningful difference in injury to the nasal muscular layer between open and closed rhinoplasty.