How Deleterious Is Facial Nerve Dissection for the Facial Nerve in Parotid Surgery: An Electrophysiological Evaluation

Continuous intraoperative neuromonitoring of the facial nerve predicts postoperative facial palsy in parotid surgery: a prospective study

PURPOSE

Facial palsy (FP) is the most significant complication of parotidectomy. Currently, the use of intermittent intraoperative neuromonitoring (iIONM) in parotid surgery facilitates nerve detection, which is paramount to nerve protection. Continuous IONM (cIONM), as applied in thyroid surgery, enables real-time information on electrophysiological nerve status through continuous nerve stimulation, thereby allowing consequent amplitude analysis. To date, the application of cIONM in parotid surgery has not been noted in literature.

METHODS

We performed parotidectomies with anterograde facial nerve visualization using cIONM in 32 consecutive patients in a prospective study (German Register of clinical studies-DRKS 00011051) during the period October 2016 to January 2020. After the facial trunk had been exposed, an atraumatic stimulation electrode was placed and the nerve was stimulated at 3 Hz, at a low threshold (0.62 ± 0.06 mA), for the entire duration of the preparation. Selected electrophysiological parameters were collected and compared to postoperative facial nerve function, measured by the House-Brackmann grading system.

RESULTS

In the post hoc analysis, a significant correlation between a drop in amplitude (< 50% of the "baseline" amplitude) and postoperative FP was recorded (p = 0.001). True positive prediction of FP was noted in 14 out of 16 patients and true negative in 10 out of 16. The sensitivity was 87.5% (AUC 0.75), with a high negative predictive value of 83.3%.

CONCLUSION

cIONM has significant value in predicting postoperative FP in parotidectomy. Future development of an acoustic/optic warning system in IONM devices could prevent nerve injury in real time.

Kabat Rehabilitation in Facial Nerve Palsy after Parotid Gland Tumor Surgery: A Case-Control Study

Temporary facial nerve palsy after parotid tumor surgery ranges from 14 to 65%, depending on surgery, tumor type, and subsite. The study aimed to evaluate the role of Kabat physical rehabilitation in the outcomes of patients affected by severe facial nerve palsy following parotid gland surgery. The results and clinical data of two groups, Kabat and non-Kabat (control), were statistically compared. Descriptive statistics, the multiple linear regression model, difference in difference approach, and the generalized linear model were used. F-Test, Chi-square test, McFadden R-squared, and adjusted R-squared were used to assess the significance. The results showed that the House–Brackmann (HB) stage of patients who had physiotherapy performed were lower than the control group. The decrease of HB staging in the Kabat group at 3 months was −0.71 on average, thus the probability of having a high HB stage decreased by about 13% using Kabat therapy. The results are statistically significant, and indicated that when the Kabat rehabilitation protocol is performed, mainly in the cases of a high-grade HB score, the patients showed a better and faster improvement in postoperative facial nerve palsy.

e-Health and telemedicine implementation in facial paralysis: challenges and pitfalls

During the current Covid-19 pandemic, a lot of changes had to be made in the care of patients with facial nerve paralysis (FNP). FNP is a life-changing condition with effects on both physical (both esthetic and functional) and psychological aspects of the patient's life. Telemedicine could be a suitable alternative in the therapy for these patients, since it is often not possible to travel to outpatient clinics or to have normal face-to-face appointments with treating physicians because of pandemic restrictions. This review provides an overview of the current literature in the treatment of FNP during the pandemic and the role of telemedicine/e-Health. Secondly, we will discuss the challenges and pitfalls of implementing e-Health and telemedicine applications in clinical practice. Level of evidence: Not ratable.

Postoperative complications after removal of pleomorphic adenoma from the parotid gland: A long-term follow up of 297 patients from 2002 to 2016 and a review of publications

Pleomorphic adenomas are rounded, lumpy, capsulated lesions that are more common in women. They are typically benign, but can be associated with malignancy in a minority of cases (such as carcinoma ex pleomorphic adenoma), between 3% - 12% of the time, according to available data. The purpose of our study was to evaluate clinical outcomes in patients with benign parotid gland tumours after extracapsular dissection (ECD) or superficial parotidectomy (SP). We made a retrospective study of 297 patients who had had benign tumours of the parotid gland, and had been referred to our department from 2002 - 2016 to have either procedure. We measured the statistical differences between the two techniques (evaluated recurrence rate and complications) with the chi squared test. The chosen level of statistical significance was p<0.05. Median (range) follow-up time was 43 months (25-168) months. Haematoma and hypoaesthesia were significantly more common after SP than after ECD (8.9% compared with 7.7%, and 16.8% compared with 5.6%, respectively). Transient facial nerve injury, Frey syndrome, and facial paralysis were significantly more common after SP than after ECD (23.6% compared with 1.5%, 6.7% compared with 1% and 6,7% compared with 0%, respectively). ECD had the advantage of reduced operating time, lower morbidity and lower recurrence rate, and could be considered the treatment of choice for pleomorphic adenoma of the parotid gland up (to 3cm) which are mobile and sited in the superficial lobe of the parotid gland.

Face-to-Face Versus Video Assessment of Facial Paralysis: Implications for Telemedicine

BACKGROUND

Patients with facial nerve paralysis (FNP) experience challenges in accessing health care that could potentially be overcome by telemedicine. However, the reliability of telemedicine has yet to be established in this field.

OBJECTIVE

This study aimed to investigate the consistency between face-to-face and video assessments of patients with FNP by experienced clinicians.

METHODS

A repeated-measures design was used. A total of 7 clinicians assessed the FNP of 28 patients in a face-to-face clinic using standardized grading systems (the House-Brackmann, Sydney, and Sunnybrook facial grading systems). After 3 months, the same grading systems were used to assess facial palsy in video recordings of the same patients.

RESULTS

The House-Brackmann system in video assessment had excellent reliability and agreement (intraclass correlation coefficient [ICC]=0.780; principal component analysis [PCA]=87.5%), similar to face-to-face assessment (ICC=0.686; PCA=79.2%). Reliability of the Sydney system was good to excellent, with excellent agreement face-to-face (ICC=0.633 to 0.834; PCA=81.0%-95.2%). However, video assessment of the cervical branch and synkinesis had fair reliability and good agreement (ICC=0.437 to 0.597; PCA=71.4%), whereas that of other branches had good to excellent reliability and excellent agreement (ICC=0.625 to 0.862; PCA=85.7%-100.0%). Reliability of the Sunnybrook system was poor to fair for resting symmetry (ICC=0.195 to 0.498; PCA=91.3%-100.0%) and synkinesis (ICC=-0.037 to 0.637; PCA=69.6%-87.0%) but was good to excellent for voluntary movement (ICC=0.601 to 0.906; PCA=56.5%-91.3%) in face-to-face and video assessments. Bland-Altman plots indicated normal limits of agreement within ±1 between face-to-face and video-assessed scores only for the temporal and buccal branches of the Sydney system and for resting symmetry in the Sunnybrook system.

CONCLUSIONS

Video assessment of FNP with the House-Brackmann and Sunnybrook systems was as reliable as face-to-face but with insufficient agreement, especially in the assessment of synkinesis. However, video assessment does not account for the impact of real-time interactions that occur during tele-assessment sessions.

The Influence of Dissection Range of the Facial Nerve on Transient Postoperative Facial Palsy in Mandibular Condyle Fractures

PURPOSE

This study examined the relation between dissection range of facial nerve branches and transient postoperative facial palsy caused by nerve traction for open treatment of mandibular condyle fractures using a preauricular approach.

MATERIALS AND METHODS

This retrospective study included 58 patients who underwent rigid fixation of condylar head and upper neck fractures. Patients were divided into 3 groups based on dissection range of the frontal and zygomatic branches. For group 1 (n = 22), the dissection range was extended anteriorly and posteriorly from the condylar borders through the retroparotid approach. The transparotid approach was used in groups 2 (n = 19) and 3 (n = 17) in which nerve dissection was limited to the condylar borders and was extended only anteriorly, respectively. Using multivariate correlation and multiple regression analyses, differences in duration of nerve traction and angle difference by traction from the natural course of the nerve were analyzed according to dissection range, and the recovery period for facial palsy was evaluated.

RESULTS

The duration of nerve traction for group 2 was 77.53 minutes, which was longer than that for groups 1 (66.00 minutes) and 3 (65.41 minutes). The angle differences by traction were 62.42° and 58.00° for the frontal and zygomatic branches in group 2, respectively, which were considerably greater than those in groups 1 (23.32° and 20.14°) and 3 (37.24° and 28.88°). In consequence, group 2 showed the longest recovery, requiring 64.47 days for the frontal branch and 51.63 days for the zygomatic branch. The angle difference by traction had a greater influence on the recovery period than duration of nerve traction.

CONCLUSIONS

Duration of nerve traction and angle difference by traction were quantitatively dependent on the dissection range of facial nerve branches and were related to the recovery period for transient facial palsy.