Segment Of Facial Nerve Research Articles

How to Avoid Facial Nerve Injury in Mastoidectomy?

Unexpected iatrogenic facial nerve paralysis not only affects facial disfiguration, but also imposes a devastating effect on the social, psychological, and economic aspects of an affected person's life at once. The aims of this study were to postulate where surgeons had mistakenly drilled or where obscured by granulations or by fibrous bands and to look for surgical approach with focused on the safety of facial nerve in mastoid surgery. We had found 14 cases of iatrogenic facial nerve injury (IFNI) during mastoid surgery for 5 years in Korea. The medical records of all the patients were obtained and analyzed injured site of facial nerve segment with surgical technique of mastoidectomy. Eleven patients underwent facial nerve exploration and three patients had conservative management. 43% (6 cases) of iatrogenic facial nerve injuries had occurred in tympanic segment, 28.5% (4 cases) of injuries in second genu combined with tympanic segment, and 28.5% (4 cases) of injuries in mastoid segment. Surgeons should try to identify the facial nerve using available landmarks and be kept in mind the anomalies of the facial nerve. With use of intraoperative facial nerve monitoring, the avoidance of in order to avoid IFNI would be possible in more cases. Many authors emphasized the importance of intraoperative facial nerve monitoring, even in primary otologic surgery. However, anatomical understanding of intratemporal landmarks with meticulous dissection could not be emphasized as possible to prevent IFNI.

Nerve crush but not displacement-induced stretch of the intra-arachnoidal facial nerve promotes facial palsy after cerebellopontine angle surgery.

Little is known about the reasons for occurrence of facial nerve palsy after removal of cerebellopontine angle tumors. Since the intra-arachnoidal portion of the facial nerve is considered to be so vulnerable that even the slightest tension or pinch may result in ruptured axons, we tested whether a graded stretch or controlled crush would affect the postoperative motor performance of the facial (vibrissal) muscle in rats. Thirty Wistar rats, divided into five groups (one with intact controls and four with facial nerve lesions), were used. Under inhalation anesthesia, the occipital squama was opened, the cerebellum gently retracted to the left, and the intra-arachnoidal segment of the right facial nerve exposed. A mechanical displacement of the brainstem with 1 or 3mm toward the midline or an electromagnet-controlled crush of the facial nerve with a tweezers at a closure velocity of 50 and 100mm/s was applied. On the next day, whisking motor performance was determined by video-based motion analysis. Even the larger (with 3mm) mechanical displacement of the brainstem had no harmful effect: The amplitude of the vibrissal whisks was in the normal range of 50°-60°. On the other hand, even the light nerve crush (50mm/s) injured the facial nerve and resulted in paralyzed vibrissal muscles (amplitude of 10°-15°). We conclude that, contrary to the generally acknowledged assumptions, it is the nerve crush but not the displacement-induced stretching of the intra-arachnoidal facial trunk that promotes facial palsy after cerebellopontine angle surgery in rats.

Obliquity of the Stapes in Otosclerosis: A New Radiological Sign.

Introduction Observing the obliquity of stapes by closely scrutinizing the HRCT temporal bone in otosclerosis revealed a reliable and consistent finding. This finding can add to the existing radiological criteria in diagnosis of otosclerosis. Objective The objective of this study is to establish the obliquity of stapes in otosclerosis by radiological measurements using HRCT temporal bone by comparing: (a) the distance between the horizontal (tympanic) segment of facial nerve and stapes head in otosclerotic ears (study group) with non-otosclerotic ears (control group); and (b) the angle subtended by stapes with promontory in the study and control groups. Methods This is a prospective study performed after the institutional Ethics Committee clearance (IEC 3/2013). Results An increased mean distance between the horizontal segment of facial nerve and stapes head in otosclerotic patients (i.e., 2.49mm +/− 0.24mm SD), when compared with the non-otosclerotic patients (i.e., 1.46mm +/− 0.16mm SD) is noted. There is a change in angle (i.e., 64.550 +/− 7.190 SD) subtended by the stapes toward the promontory in otosclerotic ears when compared with that of controls (i.e., 99.700 +/− 40 SD). We applied the Mann-Whitney U non-parametric test and considered p value of < 0.0001 highly significant. Conclusions Obliquity of stapes in otosclerosis referred to as a “Pisa” sign by the senior author has diagnostic value as a new radiological sign in imaging of otosclerosis. This obliquity explains the torsional effect of otosclerosis on the ossicular chain. The findings correlate with late complications and failures in stapes surgery.

The technique of hearing reconstruction in the cases of conductive hearing loss with malformed tympanic segment of facial nerve

To explore the technique of hearing reconstruction in the cases of conductive hearing loss with malformed tympanic segment of facial nerve. Data of 10 cases from July 2010 to March 2015 were collected.The status of tympanic segment of facial nerve, malformed ossicles and the reconstructed methods of ossicular chain were analyzed and discussed based on the embryo anatomy and surgical technique. All facial nerves in 10 cases were exposed and drooping to stapes or cover the oval window.Three patients who had normal stapes, pushed by the exposed facial nerve, were reconstructed with partial ossicular replacement prostheses (PORP). Two patients who had footplate, with partial fixation, were reconstructed with total ossicular replacement prostheses (TORP). Three patients who had atresia of the oval window were implanted with Piston after being made hole in the atresia plate.Another two cases who had atresia of the oval window were implanted with TORP after promontory being drilled out.All cases had no injury of facial nerve and nervous hearing, and no tinnitus.Nine cases had conductive hearing improvement, except one with promontory drilled out. Patients who had conductive hearing loss with malformed tympanic segment of facial nerve can be treated by the technique of hearing reconstruction.The fenestration technique in the bottom of the scala tympani of the basal turn provides us a new method for treating patients whose oval window was fully covered by malformed facial nerve.

Nonparametric Facial Feature Localization Using Segment-Based Eigenfeatures.

We present a nonparametric facial feature localization method using relative directional information between regularly sampled image segments and facial feature points. Instead of using any iterative parameter optimization technique or search algorithm, our method finds the location of facial feature points by using a weighted concentration of the directional vectors originating from the image segments pointing to the expected facial feature positions. Each directional vector is calculated by linear combination of eigendirectional vectors which are obtained by a principal component analysis of training facial segments in feature space of histogram of oriented gradient (HOG). Our method finds facial feature points very fast and accurately, since it utilizes statistical reasoning from all the training data without need to extract local patterns at the estimated positions of facial features, any iterative parameter optimization algorithm, and any search algorithm. In addition, we can reduce the storage size for the trained model by controlling the energy preserving level of HOG pattern space.

Value of visualization of the intraparotid facial nerve and parotid duct using a micro surface coil and three-dimensional fast imaging with steady state precession with fat-suppression sequence

Objective To explore the value of small surface coil combine with three-dimensional fast imaging with steady state precession and fat-suppression (3D-FISP-FS) sequence in displaying intra-parotid facial nerves segment and parotid ducts. Methods The parotid regions of 18 healthy volunteers who were excluded any parotid diseases were scanned by head & neck coil (36 sides) and 4 cm small surface coil (32 sides) combined with 3D-FISP-FS sequence prospectively. The obtained original images were treated through MIP, MPR and CPR, The MRI signal characteristics of parotid region structure, the subjective score of image quality, the signal intensity ratio (SIR) of facial nerve/parotid tissue (SIRN) and parotid duct/parotid tissue (SIRD) was calculated, and the displaying rates of the facial nerves and parotid ducts were observed. Wilcoxon matched-samples signed rank sum test was used to compare the scores of head & neck coil and small coil 3D-FISP-FS sequence images, paired t test was used to compare SIRN, SIRD of the two groups, Chi-square test was used to compare of the displaying rate of the facial nerves and parotid ducts in two groups. Results Eighteen volunteers were successfully performed MRI scan of parotid gland. On 3D-FISP-FS sequence images, the parotid gland was showed slightly low signal intensity, muscle tissue was showed medium signal intensity, the vessels were showed slightly high or high signal, parotid segment of facial nerve was showed tortuous line-like high signal intensity, and parotid duct was showed curve high signal intensity, lymph nodes were showed kidney shaped, oval or spindle shaped high signal intensity structures. The subjective scores for head and neck coil and coil images were (2.0±0.9) and (1.5±0.7) respectively, and the difference was statistically significant (Z=-2.714, P=0.007), image quality of small coil group was better than that of head and neck coil group. The SIRN of the two groups was 1.7±0.8 and 2.1±1.2 respectively, and the SIRD was 1.8±0.7 and 2.5±1.7 respectively, which showed a statistically significant difference between the two groups (t value was 2.978, 2.427 respectively, P value was 0.006, 0.031 respectively).All facial nerve trunks could be displayed by head and neck coil and small coil. On head and neck coil images, 25 sides of temporofacial truck, 15 sides of cervicofacial truck, 17 sides of temporofacial branches, 11 sides of cervicofacial branches, 16 sides of the parotid duct could be displayed. On small coil images, 30 sides of temporofacial truck, 28 sides of cervicofacial truck, 26 sides of temporofacial branches, 23 sides of cervicofacial branches, 27 sides of the parotid duct could be displayed, which showed a statistically significant difference (P<0.05). Conclusion Small surface coil performed better in parotid MR imaging with 3D-FISP-FS sequence than that of head and neck coil, which can simultaneous clearly display the trunk and branches of the intra-parotid facial nerves and parotid ducts. Key words: Parotid gland; Facial nerve; Parotid duct; Magnetic resonance imaging; Small surface coil

Infused Bone Marrow Fails to Prevent Vascularized Composite Allograft Rejection in Nonhuman Primate

Vascular composite allografts (VCA) are highly antigenic as demonstrated by near universal rejection rates. Nonetheless, substantial immunosuppressive therapy has permitted VCA to survive currently between 10 (face) and 15 (hand) years. The field of VCA has placed major emphasis on investigating in preclinical and clinical trials whether infused bone marrow combined with standard immunosuppression may improve immunologic outcomes. In contrast to solid organ transplant protocols utilizing bone marrow cells (BMC) and nonmyeloblative conditioning, tolerance (or even the absence of rejection on immunosuppression) has not been observed in any VCA trials (1.Schneeberger S Gorantla VS Brandacher G Upper-extremity transplantation using a cell-based protocol to minimize immunosuppression.Ann Surg. 2013; 257 (et al): 345-351Crossref PubMed Scopus (146) Google Scholar, 2.Devauchelle B Badet L Lengele B First human face allograft: Early report.Lancet. 2006; 368 (et al): 203-209Abstract Full Text Full Text PDF PubMed Scopus (475) Google Scholar, 3.Kawai T Sachs DH Sprangers B Long-term results in recipients of combined HLA-mismatched kidney and bone marrow transplantation without maintenance immunosuppression.Am J Transplant. 2014; 14 (et al): 1599-1611Abstract Full Text Full Text PDF PubMed Scopus (212) Google Scholar). The lack of controlled trials directly evaluating infused BMC as a cellular adjunct leads to ongoing ambiguity regarding the role of BMC infusion without preconditioning in VCA (4.Khalifian S Brazio PS Mohan R Facial transplantation: The first 9 years.Lancet. 2014; 384 (et al): 2153-2163Abstract Full Text Full Text PDF PubMed Scopus (193) Google Scholar). We have previously shown in a nonhuman primate (NHP) facial transplantation model that cotransplanted vascularized bone marrow (VBM) in the allograft improved outcomes when compared to VCA without VBM (5.Barth RN Rodriguez ED Rodriguez GS Vascularized bone marrow-based immunosuppression inhibits rejection of vascularized composite allografts in nonhuman primates.Am J Transplan. 2011; 11 (et al): 1407-1416Abstract Full Text Full Text PDF PubMed Scopus (54) Google Scholar). We have further investigated whether infused BMC could protect VCA by performing facial VCA without VBM but with donor BMC infusion Briefly, marrow was harvested from the donor lumbar vertebrae immediately following euthanasia and stored overnight using a method adapted from clinical and primate protocols. The infused marrow was analyzed for viability, cell number and percent of CD34+ hematopoietic stem and progenitor cells (HSPCs), and compared to the mandibular marrow compartment excised from the facial segment. Total nucleated cell count of hemimandibles ranged between 42.5 and 56.5 × 106 cells/kg of donor weight. Donor vertebrae yielded between 250 and 341 × 106 cells/kg donor. Viability of HSPCs immediately after processing was greater than 92.4%, with survival to postoperative day (POD) 1 of 94.8%. On POD 1, BMC were infused at a dose of 200 × 106 cells/kg of recipient weight guaranteeing greater than 2 106 HSPCs. Grafts with BMC infusion underwent early significant rejection (Banff grade II), similarly to grafts with no bone marrow component (Figure 1). Alloantibody was positive, although reduced compared to VCA without bone marrow, and in contrast to animals receiving VBM that did not produce alloantibody. One animal in the BMC infusion group progressed to complete rejection and graft loss at POD 28. A second animal progressed to chronic rejection with vessel wall thickening and C4D positivity by POD 50. The third animal resolved rejection but developed posttransplant lymphoproliferative disease (PTLD) likely secondary to LCV-mismatch. No animal with infused BMC demonstrated any evidence of chimerism, in contrast to three of four VCA + VBM animals that demonstrated transient chimerism. These data do have shortcomings, including an N of only 3, comparison to historical controls and the confounding occurrence of PTLD. However, these results suggest that VBM can protect VCA compared to BMC when performed without preconditioning. Minimal preconditioning could lead to further immunologic benefit for VBM that has the benefit of containing both cellular and stromal compartments. These data suggest that compared to infused bone marrow, VBM may improve VCA outcomes by minimizing pretransplant conditioning and chronic immunosuppression requirements, and reducing rejection episodes. The authors of this manuscript have no conflicts of interest to disclose as described by the American Journal of Transplantation. This work was performed at the University of Maryland School of Medicine, Baltimore, MD.

The image variations in mastoid segment of facial nerve and sinus tympani in congenital aural atresia by HRCT and 3D VR CT

ObjectiveTo find the variations of middle ear structures including the spatial pattern of mastoid segment of facial nerve and the shapes of the sinus tympani in patients with congenital aural atresia (CAA) by using the high-resolution (HR) CT and 3D volume rendered (VR) CT images. MethodsHRCT was performed in 25 patients with congenital aural atresia including six bilateral atresia patients (n=25, 21 males, 4 females, mean age 13.8 years, range 6–19). Along the long axis of the posterior semicircular canal ampulla, the oblique axial multiplanar reconstruction (MPR) was set to view the depiction of the round window and the mastoid segment of facial nerve. Volumetric rending technique was used to demonstrate the morphologic features. HRCT and 3D VR findings in atresia ears were compared with those in 19 normal ears of the unilateral ears of atresia patients. ResultsOn the basic plane, the horizontal line distances between the mastoid segment of the facial nerve and the round window (h-RF) in atresia ears significantly decreased compared to the control ears (P<0.05). There was a significant negative correlation between the sinus tympani area (a-ST) and the distance between the horizontal lines of FN and RW midpoint (h-RF) (P<0.05). The mean area of sinus tympani in atresia group is larger (P<0.05). The shapes of the sinus tympani were classified into three categories: the cup-shaped, the pear-shaped and the boot-shaped. Area measurement indicated that the boot-shaped sinus tympani was a special variation with a large area, which only appears in CAA group. There were a significant difference between the area of the boot-shaped group and the other two groups (P<0.05). The morphologic differences of ST and other middle ear structures can also be observed visually in 3D VR CT images. ConclusionHRCT and 3D VR CT could help a better understanding of different kinds of variations in mastoid segment of facial nerve and sinus tympani in CAA ears. And it may further help surgeons to make the correct decision for hearing rehabilitation.

Clinical characteristics and outcomes of intratemporal facial nerve neurofibromas

This study aimed to present clinical features and outcomes of 10 patients with intratemporal facial nerve neurofibromas. The ten patients underwent complete tumor removal, and nerve grafting was performed on 3 cases whose nerve integrity was sacrificed. They were followed up after surgery. All patients firstly complained of facial palsy, and progressive sensorineural hearing loss was also present in one case. Insidious onset of facial palsy was found in 6 of 10 cases (60.0%). There was multi-segment involvement in 5 of 10 cases (50.0%). During the follow-up of 4.2±1.5 ys (range, 2-6 ys), 1 of 6 cases who successfully maintained nerve integrity recovered to Grade III, and the others remained or recovered to Grade V or even Grade VI. In contrast, all of the 3 cases with nerve grafting recovered from Grade VI to Grade III or Grade IV. No tumor recurrence was noted. Facial nerve neurofibromas mainly presented with insidious facial palsy, and tended to affect multiple segments of facial nerve. It seemed that complete tumor removal and nerve grafting had better outcomes of facial nerve compared to complete tumor removal with nerve integrity preserved.

Chapter 12 - PHACE(S) syndrome

PHACE(S) syndrome is a neurocutaneous disorder of unknown etiology. The acronym refers to the commonest features of PHACE: posterior fossa malformations, large facial hemangiomas, cerebral arterial anomalies, cardiovascular anomalies, and eye anomalies. When ventral developmental defects such as sternal clefting or supraumbilical raphe occur, the PHACES acronym may be used. The hallmark feature of PHACE is the presence of one or more large facial infantile hemangiomas that occupy at least one facial segment. Infantile hemangiomas differ from the capillary malformation (port wine stain) of Sturge-Weber syndrome, and the arteriovenous malformation of Wyburn-Mason syndrome, distinguishing PHACE syndrome from other neurocutaneous disorders with red birthmarks. The true incidence of PHACE has not yet been established. Girls are more commonly affected than boys. Cerebral vascular anomalies are probably the most common extracutaneous feature. Given that several organ systems are involved, a multidisciplinary approach to disease surveillance and treatment is advised.

Significance of facial canal labyrinthine segment diameter in the pathophysiology of Bell′s palsy

Aims and Objectives: To analyze whether there is a significant difference in the width of the labyrinthine segment of the facial canal between the affected and the unaffected sides in cases of unilateral Bell's palsy, and also to ascertain whether there is any correlation between the degree of facial nerve degeneration and the width of the facial canal.Study Design: Prospective observational study. Setting: Tertiary care university hospital. Material and Methods: A total of 30 patients with unilateral Bell's palsy underwent high-resolution computed tomography with 1-mm-thick contiguous axial sections. The width of the labyrinthine portion of the facial canal at its proximal end (meatal foramen) and at the mid-labyrinthine portion was assessed on both the affected and the unaffected sides and was compared using the paired t tests. Nerve conduction studies were done to assess the degree of facial nerve degeneration. The percentage of facial nerve degeneration was compared with the width of the labyrinthine portion of the facial canal at both the aforementioned sites using the t tests of significance. Results: The width of the labyrinthine segment, both at the meatal foramen and at the mid-labyrinthine part, was significantly different on the affected side as compared with the unaffected side. The degree of facial degeneration was assessed using nerve conduction studies. Majority of the patients with less than 50% degeneration recovered within 1 month, and by 2 months, 100% of patients recovered, including those with more than 75% degeneration. The compound action potentials did not correlate significantly with the width of the facial canal. Conclusion: The width of the labyrinthine segment of the facial canal may be a potential predisposing factor in the etiopathogenesis of Bell's palsy. The degree of facial nerve degeneration, however, did not correlate with the narrowing of the labyrinthine segment of the facial canal on the affected side in Bell's palsy.

Three‐Dimensional Anatomic Analysis of Surgical Landmarks for Middle Fossa Approach

Objectives: The middle fossa approach needs the surgeon to have a 3-dimensional anatomic knowledge of internal auditory meatus (IAM), which is located underneath the middle fossa bony plate. Our purpose was to describe microsurgical anatomy of the middle fossa approach using temporal bone computed tomography (CT) 3-dimensional (3D) reconstruction. Methods: Thirty CT images of the temporal bone from patients aged between 20 and 60 years were selected. The inclusion criterion was a radiologically normal temporal bone CT scan. 3D-reconstructed images were obtained using high-resolution axial temporal bone CT scans. IAM, semicircular canal (SCC), cochlea, tympanic segment of the facial nerve (FN), geniculate ganglion (GG), and malleus were reconstructed. The length and angle among these structures was measured. Results: The mean lengths between the center of IAM and bony surface of middle cranial fossa at the Porus level was 7.7 mm (±1.0). The mean length between the superior of point of IAM of porus and GG was 15.4 mm (±1.5). The mean length between superior of point of IAM of porus and medial end of cochlear basal turn 9.9 mm (±0.9). Angle between the axis of SCC and the axis of tympanic segments of FN was 105.9° (±5.4). The mean angle between the axis of SCC and axis of IAM was 47.2° (±6.5) The mean angle between the axis of IAM and axis of tympanic segments of FN 59.6° (±10.9), The mean angle of 3-point malleus handle, GG, superior point of IAM of porus level was 113.8° (±9.8). Conclusions: The understanding of the 3D relationship in the microsurgical structure will help decide the drilling point for the IAM in case of lack of bony landmarks.

The best candidates for nerve-sparing stripping surgery for facial nerve schwannoma.

Clinical decision making for facial nerve schwannoma is particularly complicated in patients with good facial nerve function; however, an early nerve-sparing tumor resection stripping technique minimizes facial deficits associated with treatment. The present study characterized the optimal candidate for this nerve-sparing surgical strategy in patients with good facial function. Retrospective study. Nerve-sparing stripping surgery was performed on 28 patients with facial nerve schwannoma. The House-Brackmann grading system was used to assess pre- and postoperative facial function. We retrospectively analyzed pre- and postoperative facial function, duration of facial palsy, tumor size, and location and number of involved segments. The data were analyzed using Fisher exact test and independent t tests. Of the 28 patients, 18 successfully underwent stripping surgery and 16 had a favorable outcome. Favorable postoperative facial function was associated with good preoperative facial function (House-Brackmann grade [HBG] ≤II); small, localized tumors; and tumors located in the geniculate ganglion and/or its proximal portion. Patients with facial nerve schwannoma who have good preoperative facial function (HBG ≤2), tumor located in the proximal portion of the geniculate ganglion, and small tumors (<2 cm) involving one or two facial nerve segments can be the best candidates for nerve-sparing stripping surgery. 4

Congenital bifurcation of tympanic segment of facial nerve

Congenital bifurcation of tympanic segment of facial nerve

Feasibility of Using EMG for Early Detection of the Facial Nerve During Robotic Direct Cochlear Access

Facial nerve monitoring can be used synchronous with a high-precision robotic tool as a functional warning to prevent of a collision of the drill bit with the facial nerve during direct cochlear access (DCA). Minimally invasive direct cochlear access (DCA) aims to eliminate the need for a mastoidectomy by drilling a small tunnel through the facial recess to the cochlea with the aid of stereotactic tool guidance. Because the procedure is performed in a blind manner, structures such as the facial nerve are at risk. Neuromonitoring is a commonly used tool to help surgeons identify the facial nerve (FN) during routine surgical procedures in the mastoid. Recently, neuromonitoring technology was integrated into a commercially available drill system enabling real-time monitoring of the FN. The objective of this study was to determine if this drilling system could be used to warn of an impending collision with the FN during robot-assisted DCA. The sheep was chosen as a suitable model for this study because of its similarity to the human ear anatomy. The same surgical workflow applicable to human patients was performed in the animal model. Bone screws, serving as reference fiducials, were placed in the skull near the ear canal. The sheep head was imaged using a computed tomographic scanner and segmentation of FN, mastoid, and other relevant structures as well as planning of drilling trajectories was carried out using a dedicated software tool. During the actual procedure, a surgical drill system was connected to a nerve monitor and guided by a custom built robot system. As the planned trajectories were drilled, stimulation and EMG response signals were recorded. A postoperative analysis was achieved after each surgery to determine the actual drilled positions. Using the calibrated pose synchronized with the EMG signals, the precise relationship between distance to FN and EMG with 3 different stimulation intensities could be determined for 11 different tunnels drilled in 3 different subjects. From the results, it was determined that the current implementation of the neuromonitoring system lacks sensitivity and repeatability necessary to be used as a warning device in robotic DCA. We hypothesize that this is primarily because of the stimulation pattern achieved using a noninsulated drill as a stimulating probe. Further work is necessary to determine whether specific changes to the design can improve the sensitivity and specificity.

The Comparison of Histological Results of Experimentally Created Facial Nerve Defects Repaired by 2 Different Anastomosis Techniques

The objective of this study was to compare the histological regeneration characteristics of nerve fibers at the anastomosis lines performed by classic suture technique or a tissue adhesive (N-butyl-2-cyanoacrylate). The control group consisted of 7 rabbits. The 21 rabbits were randomly divided into 3 groups based on the harvesting week. In the study group following preparation of facial nerve bilaterally, a 0.5-cm segment of facial dorsal buccal nerve was resected, and the defect was repaired with a nerve graft, which was harvested from sural nerve of the same side by 8-0 nylon suture technique and by application of N-butyl-2-cyanoacrylate on the other side. Electron microscopic examination at consecutive second, fourth, and sixth days (corresponding to 4th, 8th, and 12th week in human subjects) revealed increased nerve degeneration findings in N-butyl-2-cyanoacrylate group when compared with microsuture repair technique. We conclude that N-butyl-2-cyanoacrylate is not an appropriate material for nerve anastomosis.

Facial Nerve Palsy Associated with a Cystic Lesion of the Temporal Bone

Facial nerve palsy results in the loss of facial expression and is most commonly caused by a benign, self-limiting inflammatory condition known as Bell palsy. However, there are other conditions that may cause facial paralysis, such as neoplastic conditions of the facial nerve, traumatic nerve injury, and temporal bone lesions. We present a case of facial nerve palsy concurrent with a benign cystic lesion of the temporal bone, adjacent to the tympanic segment of the facial nerve. The patient's symptoms subsided after facial nerve decompression via a transmastoid approach.

Side-to-End Hypoglossal to Facial Anastomosis With Transposition of the Intratemporal Facial Nerve

To describe results in a large series of patients using a recent variation of hypoglossal-facial nerve anastomosis (HFA) in which the intratemporal facial nerve segment is used, obviating the need for a sensory nerve "jump graft." Retrospective chart review. Tertiary neurotologic referral center. Nineteen patients (12 female/7 male subjects) with facial paralysis because of posterior fossa surgery for tumor (n = 15), Bell's palsy (n = 1), facial neuroma (n = 1), hemangioma (n = 1), and trauma (n = 1) who underwent HFA from 1997 to 2011, with at least 1-year follow-up. Mean age at surgery is 47.4 years (range, 11.2-83 yr). Mean follow-up is 4.0 years. Side-to-end hypoglossal to facial anastomosis with transposition of the intratemporal facial nerve (swingdown HFA). House-Brackmann (H-B) facial nerve grade. Seven patients (36.8%) achieved an H-B Grade III, 9 patients (47.4%) a grade IV, and 3 patients (15.8%) a grade V at last follow-up. No patients complained of dysphagia, dysarthria, or had evidence of oral incompetence. One patient complained of mild tongue weakness. Age at time of HFA (p ≤ 0.049, III younger than V) and time from facial nerve injury to HFA (p ≤ 0.02, III<IV and V) were significant factors for ultimate facial nerve outcome. All patients with an H-B III result had HFA within 6 months of injury. Other factors were not significant. The HFA swingdown technique is a safe and effective method to restore facial nerve function in patients with facial paralysis and obviates the need for an interposition jump graft.

Isolated Adenoma with Neuroendocrine Differentiation Involving Both the Facial Nerve and Parotid Gland

Objective: To report an extremely rare case of neuroendocrine tumour with simultaneous involvement of both the facial nerve and the deep lobe of parotid gland. Method: case report and English language literature review concerning neuroendocrine neoplasm involving the facial nerve with emphasis on clinical presentation. Results: We report a unique case of adenoma with neuroendocrine differentiation which involved both the mastoid segment of the right facial nerve and also the deep lobe of the parotid gland on the ipsilateral side. Both tumours were not contiguous and were anatomically separate from each other. A CT scan of the whole body revealed no other neuroendocrine tumours. Conclusion: To the best of our knowledge, this is the first report in the English language literature of a neuroendocrine tumour to involve both the vertical mastoid segment of the facial nerve with simultaneous involvement of the deep lobe of parotid gland as a separate lesion.

Surgical findings to differentiate between facial nerve schwannoma and vestibular schwannoma.

ObjectivesFacial nerve schwannomas may be misdiagnosed as vestibular schwannomas (VSs) if the tumor is confined to the internal auditory canal (IAC) without involvement the geniculated ganglion or labyrinthine segment of facial nerve. Because facial nerve schwannomas may be misdiagnosed as VSs, we investigated the differences between the two.MethodsThe study included 187 patients with a preoperative diagnosis of VS. Of these, six were diagnosed with facial nerve schwannomas during surgery. We reviewed the preoperative evaluations and surgical findings of facial nerve schwannomas mimicking VSs.ResultsNo useful preoperative predictors are available for facial nerve schwannomas mimicking VSs. Facial nerve schwannomas are usually confined to the IAC. After opening the dura of the IAC, a facial nerve schwannoma can be diagnosed after identifying a normal-appearing nerve located lateral to the tumor. When this was the case, we performed facial nerve preservation surgery or decompression.ConclusionFacial nerve schwannomas can be differentiated from VSs by identifying specific findings during surgery.