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Hypothesis: Early nerve-sparing tumor resection is designed to minimize facial deficits associated with facial nerve schwannomas. This report aimed to determine optimal treatment approaches and timing in patients with facial nerve schwannomas, especially those with good facial function., Background: Clinical decision making is complicated in patients with good facial nerve function because classical surgical treatment consists of excision of the tumor along with the involved nerve segment, followed by grafting or primary anastomosis, which can result in permanent facial deficits., Methods: Since 1995, we have conducted a nerve-preserving technique on 15 patients with facial nerve schwannomas to obtain better results after our experience with the 10 patients who underwent tumor resection and/or facial nerve reconstruction before 1995 and evaluated the surgical outcomes of all 25 patients between 1990 and 2008. The House-Brackmann (HB) grading system for facial nerve function was used to assess preoperative and postoperative functions with follow-up magnetic resonance imaging to monitor for tumor recurrence., Results: At the final functional assessment, 7 patients had no change in facial function, 2 had improved, and 6 had worsened. Specifically, 4 patients had normal facial function, 8 had HB Grade II, and 3 had HB Grade III. To date, no clinical or radiologic evidence of recurrence has been detected in any of the patients, all of whom underwent postoperative enhanced magnetic resonance imaging at least 3 years after surgery., Conclusion: Facial nerve-preserving technique is recommended for resection of facial nerve schwannomas, especially in patients with good preoperative facial function. Compared with the resection-and-reconstruction technique, this method can prevent delays in presurgical deterioration of the neural fascicle and may result in better postoperative facial function.

Much controversy surrounds the etiology and management of Bell's palsy, and the pathogenetic mechanisms underlying Bell's palsy remain obscure despite the extensive body of relevant research. The pathological condition of Bell's palsy is almost an inflammatory reaction compressing the facial nerve in the fallopian canal, particularly in the narrowest labyrinthine segment, followed by demyelinating neural change. As one of the best method for the visualization of the inflamed facial nerve in the intratemporal segment, temporal bone CT enable us not only to measure the exact length and thickness of individual segments of the facial nerve canal but also to view variable anatomic variations in the intratemporal facial canal. Some suggest that anatomical variation may predispose the nerve to inflammatory processes and also there can be peculiar structures of the temporal bone that are vulnerable to inflammation or neural compression injury., (Copyright © 2011 Elsevier Ltd. All rights reserved.)

Hypothesis: The purpose of this study was to investigate whether computed tomography (CT) could predict the possibility of first genu exposure of the facial nerve via the transmastoid approach in patients with acute facial paralysis., Background: Temporal bone CT is the best method for visualizing the intratemporal segment of the facial nerve canal, which is known to have diverse anatomic variations., Methods: A prospective study was conducted on 11 patients who underwent facial nerve decompression via the transmastoid approach. Two groups of patients underwent surgery to expose the perigeniculate area via the transmastoid approach. One group included patients who had anatomic parameters of the temporal bone that met the CT criteria, including length of the labyrinthine segment, level of the geniculate ganglion, bony thickness of the lateral semicircular canal, and height interval between the tympanic and labyrinthine segments. The other group included patients with facial paralysis who required facial nerve exploration, especially distal to the geniculate ganglion. Facial nerve decompression was performed in all patients as far proximal in the transmastoid view as was possible without causing damage to the semicircular canals., Results: We correlated the temporal bone CT images and surgical findings in 11 patients who underwent facial nerve decompression via the transmastoid approach. The facial nerves of 6 patients who had anatomic structures that met the CT criteria were successfully exposed to the proximal labyrinthine segment without labyrinthine damage. The facial nerves of another 4 patients who did not have anatomic structures that met the CT criteria could be decompressed only to the geniculate ganglion., Conclusion: CT scan can predict the possibility of first genu exposure of the facial nerve via the transmastoid approach based on the CT parameters suggested in this study.

We sought to determine whether electrical stimulation (ES) with subthreshold, continuous, low-frequency impulses is a viable clinical method for improving functional recovery after facial nerve crush injury. In 10 rabbits, bilateral crush injuries were made on the facial nerve by compression for 30 s with mosquito forceps, causing complete facial paralysis. Subthreshold continuous direct current ES with 20-Hz square-wave pulses was applied to the proximal stump on one side for 4 weeks. Vibrissae movement returned significantly earlier on the ES side, with a less variable recovery time. Electrophysiologically, the stimulated side had a significantly shorter latency, longer duration, and faster conduction velocity. Light and transmission electron microscopy revealed that the electrical stimulation also markedly decreased Wallerian degeneration. The average numbers of fluorescent, double-labeled nerve cells were significantly different between the ES and non-ES sides. This study shows that subthreshold, continuous, low-frequency ES immediately after a crush injury of the facial nerve results in earlier recovery of facial function and shorter overall recovery time., (Copyright © 2011 Wiley Periodicals, Inc.)

The management of the facial nerve in tumorous temporal lesions is particularly challenging due to its complex anatomic location and potential postoperative complications, including permanent facial paralysis. The most important concern regarding surgical treatment of a tumorous temporal lesion is the inevitable facial paralysis caused by nerve injury during the tumor removal, especially in patients with minimal to no preoperative facial nerve dysfunction. We describe successful four cases in which various surgical techniques were developed for the preservation of the facial nerve in treatment of intratemporal tumorous lesions., (Copyright (c) 2009 Elsevier Ireland Ltd. All rights reserved.)

Conclusion: This study demonstrates good correlation between enhanced MRI and surgical findings., Objectives: This study investigated the reliability of enhanced magnetic resonance imaging (MRI) to make a surgical decision on the strategy for facial nerve decompression in herpes zoster oticus, by determining the degree of correlation between contrast enhancement in MRI and the pathologic change in the facial nerve., Subjects and Methods: This retrospective study of 13 patients, who underwent facial nerve decompression with herpes zoster oticus, was designed to compare gadolinium-enhanced segment of facial nerve on MRI and the pathologically changed segment confirmed by surgical exploration, grouping them by the timing of operation after onset of facial paralysis., Results: Commonly enhanced segments on MRI were the labyrinthine, intracanalicular, and geniculate ganglion, found in 84%, 69%, and 69% of all patients, respectively. The most common pathologic segment was the labyrinthine segment (92%), followed by the geniculate ganglion (84%).

Conclusions: Quantitative analysis of the facial nerve on the lesion side as well as the normal side, which allowed for more accurate measurement of facial nerve enhancement in patients with facial palsy, showed statistically significant correlation with the initial severity of facial nerve inflammation, although little prognostic significance was shown., Objectives: This study investigated the clinical significance of quantitative measurement of facial nerve enhancement in patients with Bell's palsy by analyzing the enhancement pattern and correlating MRI findings with initial severity of facial palsy and clinical outcome., Subjects and Methods: Facial nerve enhancement was measured quantitatively by using the region of interest on pre- and postcontrast T1-weighted images in 44 patients diagnosed with Bell's palsy. The signal intensity increase on the lesion side was first compared with that of the contralateral side and then correlated with the initial degree of facial palsy and prognosis., Results: The lesion side showed significantly higher signal intensity increase compared with the normal side in all of the segments except for the mastoid segment. Signal intensity increase at the internal auditory canal and labyrinthine segments showed correlation with the initial degree of facial palsy but no significant difference was found between different prognostic groups.

Objective: We report six cases of facial nerve schwannomas in which surgical management allowed the preservation of facial nerve function. Specifically, this paper reports that a stripping surgery may provide favorable functional outcomes., Study Design: A retrospective review of preoperative and postoperative data for six patients with facial nerve schwannoma that had normal facial nerve function or a House-Brackmann grade II facial palsy before the surgery., Methods: Stripping surgery, which removed the schwannoma from the remaining nerve fascicle, was attempted on the six patients. Postoperative facial nerve function and imaging (magnetic resonance imaging) were evaluated., Results: Stripping surgery with gross total tumor removal of the mass was performed in four cases. In the two remaining cases, the stripping surgery was not possible, and decompression alone was performed. Favorable preservation of facial function was achieved in all six cases., Conclusion: It was possible to preserve facial function after surgery to remove facial nerve schwannoma. We suggest that stripping surgery, focused on the preservation of continuity of the facial nerve, may be attempted for facial nerve schwannoma in which favorable facial function has been preserved.

Objective: To investigate the capability of preoperative evaluations in predicting the precise anatomic origin of intracanalicular tumors., Study Design: We conducted a retrospective case review., Setting: Tertiary referral center., Patients: A total of 11 patients (8 men and 3 women, 26-70 years old) with intracanalicular tumors who were treated surgically were included., Interventions: Pure-tone average, auditory brainstem response, caloric test, and temporal magnetic resonance imaging were done in all 11 patients. Electroneuronography has only been performed since 2003, and only 3 patients were evaluated., Main Outcome Measure: Preoperative symptoms, pure-tone average, auditory brainstem response, caloric test, electroneuronography, and magnetic resonance imaging were compared between patients with facial nerve schwannomas and patients with vestibular schwannomas., Results: Postoperatively, facial nerve schwannomas were diagnosed pathologically in 2 (18%) of 11 patients. There were not any clues suggesting facial nerve schwannoma in preoperative evaluations., Conclusion: A facial nerve schwannoma may be misdiagnosed as a vestibular schwannoma, especially when the tumor is confined to the internal auditory canal. There are no useful preoperative evaluation tools in predicting the precise nerve origin of intracanalicular tumors. These emphasize the need to fully inform the patient preoperatively.

The middle cranial fossa approach is useful for decompressing the perigeniculate ganglion area of the facial nerve in patients with serviceable hearing. The present study was designed to investigate the microsurgical anatomy of the perigeniculate ganglion area of the facial nerve from the point of view of the middle cranial fossa. We dissected 20 human temporal bones under a microscope using a middle fossa approach, and measured the angle between the lines drawn from the malleus head to the vertical crest and from the malleus head to the geniculate ganglion, and the distance from the malleus head to the geniculate ganglion. These were found to be 22.7 degrees +/- 2.2 degrees and 6.5 +/- 0.3 mm, respectively. Detailed knowledge about the microsurgical anatomy of the perigeniculate ganglion area of the facial nerve from the point of view of the middle cranial fossa is imperative for facial nerve decompression by a middle cranial fossa approach.

Conclusion: The earlier decompression is carried out, the better the result. However, decompression delayed a few days beyond 2 weeks after onset of facial paralysis can benefit the recovery of facial function in patients when combined with early use of steroids with or without antiviral agents. Objectives: To demonstrate the correlation between the time of decompression after the onset of facial paralysis and the facial function after surgery and elucidate the beneficial effect of decompression delayed a few days beyond the 2 week period on recovery of facial function in patients who had received early steroid treatment. Patients and methods: Between April 1994 and December 2007, 91 patients with complete facial paralysis who had received early treatment with steroid with or without antiviral agents were included in the study. An independent sample t test was used to analyze the recovery of facial function in patients receiving surgical decompression at different times after onset of paralysis and medical treatment only. Results: Functional gain according to the House-Brackman (HB) grade was 4.05±0.96 for early decompression, 3.63±0.58 for delayed decompression, 2.90±0.76 for late decompression, and 2.51±0.85 for medical treatment only. Delayed decompression significantly improved the functional outcome of patients compared with late decompression and medical treatment only ( p<0.05). [ABSTRACT FROM AUTHOR]