Photobiomodulation enhances facial nerve regeneration via activation of PI3K/Akt signaling pathway-mediated antioxidant response.

Facial nerve dysfunction is a common clinical condition that leads to disfigurement and emotional distress in the affected individuals. This study aimed to evaluate whether photobiomodulation can enhance regeneration of crushed facial nerves and attempt to investigate the possible underlying mechanism of neuroprotective function and therapeutic target. Various parameters of photobiomodulation were assigned to the facial nerves and Schwann cells (SCs) separately during crushed injury in rats. Axonal regeneration, functional outcomes, and SC apoptosis, proliferation, and underlying mechanisms of action were evaluated by morphological, histopathological, and functional assessments, flow cytometry, western blotting, real-time PCR, and IncuCyte. The results showed that photobiomodulation improved axonal regeneration and functional recovery, and also promoted proliferation, and inhibited apoptosis of SCs, both of these were considered as the most effective parameters in 250mW group. In addition, the neuroprotective effects of photobiomodulation (500mW) were likely associated with oxidative stress-induced SC apoptosis via activation of the PI3K/Akt signaling pathway. Our results revealed that photobiomodulation significantly promoted axonal regeneration, functional recovery, and regeneration of the facial nucleus, and its mechanism was related to the up-regulation of the PI3K/Akt signaling pathway. These findings provide clear experimental evidence of photobiomodulation as an alternative therapeutic strategy for peripheral nerve damage.

Advance in Functional Restoration of Injured Nerve with Low Level Laser and its Utilization in the Dental and Maxillofacial Region.

The inferior alveolar nerve and facial nerve are the two most important nerves in the dental and maxillofacial region. The injury to them is one of the major postoperative complications after alveolar surgery and orthognathic surgery. However, recovering the nerve function after injury takes a long time and the recovery effect tends to be unsatisfactory. In recent years, an intensively investigated technique, low level laser which has been applying in assisting the recovery of nerve function, has been gradually proved to be effective in clinically treating postoperative nerve injury. In this article we review in terms of the mechanisms involved in low level laser-assisted functional restoration of nerve injury and its clinical application in the recovery of nerve function in the dental and maxillofacial area as well.

Photobiomodulation Therapy to Treat Facial Paralysis of 8 Years: Case Report.

Background: Paralysis of the facial muscles produces functional and aesthetic disturbance that has a negative impact for the patient's quality of life. Objective: To evaluate the effects of a photobiomodulation (PBM) with low-level laser (LLL) on the treatment of a patient with 8 years of facial paralysis. Methods: PBM with two different wavelengths of LLL (660 and 808 nm), applied only on the affected side, three times a week for 8 consecutive weeks. Evaluations were performed before starting treatments, after the 12th session of treatment and after the 24th session, using the House-Brackmann scale and electroneuromyography. Results: The House-Brackmann and electroneuromyography tests showed improvements in the movement of the facial muscles when tested in the middle and at the end of the treatment with LLL. Conclusions: PBM with LLL at the wavelength of 660 and 808 nm with the parameters used in this case report was an effective and noninvasive treatment for facial paralysis in this long-standing, chronic case of 8 years.

Twelve-year results of LINAC-based radiosurgery for vestibular schwannomas.

PURPOSE: To report long-term outcomes of 53 patients with vestibular schwannomas (VS) submitted to a single high-dose LINAC-based radiosurgery (SRS) in our institution. METHODS: 48 (92%) patients were evaluable for clinical and MRI response as well as late toxicity. At a median follow-up of 12 years (range 2-16 years), local control (LC), hearing capacity, trigeminal and facial nerve function, and toxicity were assessed. Hearing capacity was classified according to the Gardner-Robertson scale, where class I-II patients had "serviceable hearing." RESULTS: Median dose of SRS was 16.5 Gy (range 13-20 Gy) and median tumor volume 1.7 cm3 (range 0.09-7.4 cm3). 35 (73%) patients were treated with SRS alone, in the remaining 13 (27%) patients, SRS was performed as salvage therapy for recurrent or progressive tumors after previous microsurgery. Before SRS, 44 patients (92%) had hearing loss and 25 (52%) had "non-serviceable" hearing. Tumor extension, classified with Koos categories, was grade I-II in 27 (56%) and grade III-IV in 21 (44%) cases. LC was 100% and hearing preservation in "serviceable hearing" patients was 91%. 4 (11%) patients developed incomplete and intermittent ipsilateral facial nerve palsy which regressed in a median time of 6 months. Trigeminal toxicity was registered in 11 (23%) patients, reversible in 6 (13%) and permanent in 5 (10%). Only Koos tumor grade III-IV significantly influenced late toxicity (p = 0.01). CONCLUSION: LC and hearing preservation after SRS were excellent. Toxicity proved acceptable. Although the median administered dose (16.5 Gy) was rather high, the only factor which significantly influenced late toxicity was Koos tumor grade III-IV.

Three-Dimensional Printed Plate-Guided 125I Brachytherapy for Malignant Parotid Tumors.

PURPOSE: The treatment of malignant parotid tumors with 125I brachytherapy is rarely reported. This study evaluated the efficacy and dose and response of 125I brachytherapy in patients with malignant tumors. MATERIALS AND METHODS: From July 2014 through August 2017, 39 patients with malignant parotid tumors were treated with 125I brachytherapy. Thirty-five patients were treated with conservative surgical resection before brachytherapy. Four patients were treated with brachytherapy alone. Clinical outcomes and side effects were evaluated. Clinical factors were investigated to determine correlations with local control (LC) and side effects. RESULTS: Mean follow-up was 25 months (range, 7 to 47 months). The LC rate was 87.2% and the overall survival rate was 97.4%. High tumor grade and large tumor showed a propensity for local recurrence. Acute skin toxicity occurred in 87.2% of patients and grade 3 and 4 radioepidermitis was found in 20.5% of patients. In total, 89.7% of patients with facial nerve dysfunction recovered within 12 months. CONCLUSIONS: 125I brachytherapy was a feasible treatment option for patients with malignant parotid tumors. Although side effects were minimal, strict follow-up was necessary for patients treated with a high dose.

Efficacy of Laser Photobiomodulation on Morphological and Functional Repair of the Facial Nerve.

OBJECTIVE: Evaluate the efficacy of low-level laser therapy (LLLT) on qualitative, quantitative, and functional aspects in the facial nerve regeneration process. MATERIALS AND METHODS: Forty-two male Wistar rats were used, randomly divided into a control group (CG; n = 10), in which the facial nerve without lesion was collected, and four experimental groups: (1) suture experimental group (SEG) and (2) fibrin experimental group (FEG), consisting of 16 animals in which the buccal branch of the facial nerve was sectioned on both sides of the face; an end-to-end epineural suture was performed on the right side, and a fibrin sealant was used on the left side for coaptation of the stumps; and (3) laser suture experimental group (LSEG) and (4) laser fibrin experimental group (LFEG), consisting of 16 animals that underwent the same surgical procedures as SEG and FEG with the addition of laser application at three different points along the surgical site (pulsed laser of 830 nm wavelength, optical output power of 30 mW, power density of 0.2586 W/cm2, energy density of 6.2 J/cm2, beam area of 0.116 cm2, exposure time of 24 sec per point, total energy per session of 2.16 J, and cumulative dose of 34.56 J). The animals were submitted to functional analysis (subjective observation of whisker movement) and the data obtained were compared using Fisher's exact test. Euthanasia was performed at 5 and 10 weeks postoperative. The total number and density of regenerated axons were analyzed using the unpaired t-test (p < 0.05). RESULTS: Laser therapy resulted in a significant increase in the number and density of regenerated axons. The LSEG and LFEG presented better scores in functional analysis in comparison with the SEG and FEG. CONCLUSIONS: LLLT enhanced axonal regeneration and accelerated functional recovery of the whiskers, and both repair techniques allowed the growth of axons.

Nervus Intermedius Symptoms following Surgical or Radiation Therapy for Vestibular Schwannoma.

OBJECTIVES: This study compares the functional outcomes of nevus intermedius impairment following surgery, radiation, or observation for the treatment of vestibular schwannoma. STUDY DESIGN: Retrospective cohort study. SETTINGS: Tertiary care medical center. SUBJECTS AND METHODS: We retrospectively examined 141 charts of patients with a vestibular schwannoma seen in the Dartmouth-Hitchcock Acoustic Neuroma Clinic between 2012 and 2014. Seventy-one patients underwent intervention (including radiation) as their primary treatment, and 70 were treated with observation. As part of routine care, patients were interviewed at clinic visits and with a questionnaire assessing nervus intermedius impairment. RESULTS: At presentation, 25 patients (19%) reported nervus intermedius impairment. Most common disturbances were xerophthalmia (dry eyes, 13%) and dysgeusia (taste alteration, 7.6%). Postintervention, 35 patients (53%) had ≥1 symptoms of nervus intermedius dysfunction, which is increased in comparison with patients in the observation group (17 patients, 26.5%, P < .05). Twelve intervention patients had symptoms resolve postoperatively, making no long-term difference between the observation and intervention groups (P = .20). Motor function of the facial nerve postoperatively is correlated with nervus intermedius symptoms. Surgical approaches were compared with radiation therapy, and no significant difference in nervus intermedius outcomes was found. CONCLUSION: This study demonstrates the clinical importance of monitoring nervus intermedius symptoms, since a high percentage of all patients undergoing intervention will be symptomatic during management. Patients with motor dysfunction are at a higher risk of developing nervus intermedius sequelae and need close follow-up. Although impairment is common, many symptoms will improve over time with no long-term difference between intervention patients and those under observation.

The new heterologous fibrin sealant in combination with low-level laser therapy (LLLT) in the repair of the buccal branch of the facial nerve.

This study aimed to evaluate the effects of low-level laser therapy (LLLT) in the repair of the buccal branch of the facial nerve with two surgical techniques: end-to-end epineural suture and coaptation with heterologous fibrin sealant. Forty-two male Wistar rats were randomly divided into five groups: control group (CG) in which the buccal branch of the facial nerve was collected without injury; (2) experimental group with suture (EGS) and experimental group with fibrin (EGF): The buccal branch of the facial nerve was transected on both sides of the face. End-to-end suture was performed on the right side and fibrin sealant on the left side; (3) Experimental group with suture and laser (EGSL) and experimental group with fibrin and laser (EGFL). All animals underwent the same surgical procedures in the EGS and EGF groups, in combination with the application of LLLT (wavelength of 830 nm, 30 mW optical power output of potency, and energy density of 6 J/cm(2)). The animals of the five groups were euthanized at 5 weeks post-surgery and 10 weeks post-surgery. Axonal sprouting was observed in the distal stump of the facial nerve in all experimental groups. The observed morphology was similar to the fibers of the control group, with a predominance of myelinated fibers. In the final period of the experiment, the EGSL presented the closest results to the CG, in all variables measured, except in the axon area. Both surgical techniques analyzed were effective in the treatment of peripheral nerve injuries, where the use of fibrin sealant allowed the manipulation of the nerve stumps without trauma. LLLT exhibited satisfactory results on facial nerve regeneration, being therefore a useful technique to stimulate axonal regeneration process.

Percutaneous Selective Neuromodulation via Monopolar Radiofrequency for Glabellar Lines: A Case Study.

INTRODUCTION: Injectable botulinum toxin is a safe, effective, and popular therapy that blocks neural impulses to achieve a desired effect. Using monopolar RF, percutaneous selective neuromodulation can achieve a similar but more persistent effect. METHODS: Bilateral treatment was performed on a woman (48 years of age) to ablate the angular nerves of the face, inhibiting muscular function and reduce the appearance of glabellar lines. The cannula was inserted at the mid-pupillary line and advanced toward the lateral border of the nose. After isolating the nerve via low-level stimulation, anesthetic was given through a port in the cannula and energy was applied; tissue temperature of 85 °C was maintained for 70 seconds. RESULTS: Full ablative lesioning of the angular nerve of the patient was achieved and function was therapeutically inhibited with minimal pain. Results have persisted for more than two years.

Radiotherapy in patients with vestibular schwannoma and neurofibromatosis type 2: clinical results and review of the literature.

AIMS AND BACKGROUND: To evaluate the long-term outcome of patients with vestibular schwannoma (VS) and neurofibromatosis type 2 (NF2) treated with fractionated stereotactic radiotherapy (FSRT) or stereotactic radiosurgery (SRS). PATIENTS AND METHODS: Sixteen VS in 14 patients with NF2 were treated with FSRT (n = 14) and SRS (n = 2). Patients with tumor progression and/or progression of clinical symptoms were selected for treatment. For patients treated with FSRT a median total dose of 57.6 Gy was prescribed with a median fractionation of 5 × 1.8 Gy per week. For patients who underwent SRS a median single dose of 17 Gy was prescribed to the 80% isodose. RESULTS: FSRT and SRS were well tolerated. Local control rate was 94% for a median follow-up time of 131 months; 2- and 5-year progression-free survival were 100%. The probability of maintaining the pretreatment hearing level was 44%. Useful hearing preservation was 33%. Cranial nerve toxicity was moderate. Trigeminal nerve function worsened in 2 patients (12%) and facial nerve function in 3 patients (19%). One patient developed a new tinnitus. CONCLUSION: FSRT and SRS are both safe and effective noninvasive and minimally invasive treatment options for patients with VS in the setting of NF2. The long-term local control rates are excellent. Functional hearing preservation is worse in patients with VS and NF2 than in patients with sporadic VS.