Research & Current Literature
List compiled by Robin Lindsay, M.D.
Starritt, N. E., S. A. Kettle, et al. (2011). "Sutureless repair of the facial nerve using biodegradable glass fabric." Laryngoscope 121(8): 1614-1619.
OBJECTIVES/HYPOTHESIS: To compare a sutureless method of facial nerve repair using a biodegradable glass fabric with the standard method of microsurgical suture. STUDY DESIGN: The facial nerve was transected in groups of six sheep and repaired by either entubulation with a biodegradable glass fabric or standard microsurgical epineurial suture repair. METHODS: Both methods of repair were compared with each other and with a normal control group using electrophysiological and morphometric analysis. RESULTS: Maximum conduction velocity, axon and fiber diameter, and myelin-sheath thickness were all reduced in the repaired nerves when compared with the normal nerves. There was no significant difference among any of the outcome variables between the repair groups. CONCLUSIONS: Repair of nerve injuries by entubulation has several theoretical advantages over standard suture repair: less trauma to nerve ends, no need for microsurgical skills, and delivery of neurotrophic growth factors. It is concluded that repair of the facial nerve by glass-wrap entubulation offers an alternative to standard suture repair without the demands of microsurgery on both time and surgical expertise.
Fattah, A., G. H. Borschel, et al. (2011). "Reconstruction of facial nerve injuries in children." J Craniofac Surg 22(3): 782-788.
Facial nerve trauma is uncommon in children, and many spontaneously recover some function; nonetheless, loss of facial nerve activity leads to functional impairment of ocular and oral sphincters and nasal orifice. In many cases, the impediment posed by facial asymmetry and reduced mimetic function more significantly affects the child's psychosocial interactions. As such, reconstruction of the facial nerve affords great benefits in quality of life. The therapeutic strategy is dependent on numerous factors, including the cause of facial nerve injury, the deficit, the prognosis for recovery, and the time elapsed since the injury. The options for treatment include a diverse range of surgical techniques including static lifts and slings, nerve repairs, nerve grafts and nerve transfers, regional, and microvascular free muscle transfer. We review our strategies for addressing facial nerve injuries in children.
Claflin, E. S. and L. R. Robinson (2011). "How soon after temporal bone fracture should we perform electroneurography?" Muscle Nerve 44(2): 304.
Ozmen, O. A., M. Falcioni, et al. (2011). "Outcomes of facial nerve grafting in 155 cases: predictive value of history and preoperative function." Otol Neurotol 32(8): 1341-1346.
OBJECTIVE: : To investigate the factors that were effectual on the recovery of the facial nerve functions after repair with grafting. STUDY DESIGN: : Retrospective case review. SETTING: : Private neuro-otologic and cranial base quaternary referral center. PATIENTS: : One hundred ninety-four patients underwent facial nerve grafting during lateral cranial base surgery between July 1989 and December 2009. The mean age of the patients was 44.1 +/- 15.8 years (range, 2-79 yr). There were 94 male and 100 female patients. Facial nerve functions were normal in 89 patients, whereas facial nerve paresis or paralysis was present for a mean duration of 25.4 months (range, 1-600 mo) in the rest of the patients. MAIN OUTCOME MEASURE: : Final facial nerve motor function. RESULTS: : Best outcome, which was Grade III according to House-Brackmann scale, was achieved in 105 of 155 patients with a follow-up of 1 year or longer (67.7%). Final result was grade IV in 23 (14.8%), grade V in 8 (5.2%), and grade VI in 19 patients (12.3%). Preoperative deficit duration was found to be the only significant factor that affected the prognosis (p = 0.027). Receiver operating characteristic curve analysis revealed that the most critical time for recovery to grades III and IV function is 6 months (p < 0.001). CONCLUSION: : A number of factors were implicated to affect the success rate of facial nerve grafting, but only the duration of preoperative facial nerve deficit was found to be significant. Thus, timely management of facial nerve problems is critical for achieving optimal results.
Wilkinson, E. P., M. Hoa, et al. (2011). "Evolution in the management of facial nerve schwannoma." Laryngoscope.
OBJECTIVE: To design a treatment algorithm based on experience with facial nerve schwannomas (FNS) over a 30-year period. STUDY DESIGN: Retrospective chart review. METHOD: Seventy-nine patients with facial nerve schwannomas seen from 1979 through 2009 at a tertiary referral private otologic practice were categorized by treatment modality. Interventions included surgical resection with grafting, bony decompression, observation, or stereotactic radiation. Outcome measures included House-Brackmann facial nerve grade before and after intervention as well as change in facial nerve grade, tumor size, involved segments of nerve, time to intervention. RESULTS: Thirty-seven patients (46.8%) ultimately underwent surgical excision with grafting or primary anastomosis, 21 (26.6%) underwent bony decompression alone, 15 (19.0%) were managed with observation only, and 6 (7.6%) had stereotactic radiation. Through 1995, 85% of cases had surgical resection and none had observation only. Of the 52 patients seen after 1995, 27% had surgical resection and grafting, 33% had bony decompression, 29% were managed with observation alone, and 11% had radiotherapy. Facial nerve grade was maintained or improved over the follow-up period (mean time = 3.9 years) in 78.9% of the decompression group and 100% of the observation and radiation groups compared to 54.8% of the resection group (P </= .012). CONCLUSIONS: Surgical treatment, once widely accepted and practiced, has in many cases given way to observation, bony decompression, or stereotactic radiation. A wide armamentarium of options is available to the neurotologist treating facial nerve schwannomas with the ability to preserve facial function for a longer period of time.
Klingner, C. M., G. F. Volk, et al. (2011). "Time Course of Cortical Plasticity After Facial Nerve Palsy: A Single-Case Study." Neurorehabil Neural Repair.
BACKGROUND: . Functional connectivity is defined as the temporal correlation between spatially remote neurophysiological events. This method has become particularly useful for studying neuroplasticity to detect changes in the collaboration of brain areas during cortical reorganization. METHODS: . In this article, the authors longitudinally studied voxel-based morphometry and resting state functional magnetic resonance imaging 10 times in 1 patient during the course of Bell palsy (idiopathic facial nerve palsy) up to complete clinical recovery. RESULTS: . Morphometric analysis revealed a significant alteration in the face area of the primary motor cortex (M1) contralateral to the paretic face, with an initial increase in gray matter concentration. Functional connectivity analysis between the M1 and other parts of the facial motor network revealed acutely disrupted intrahemispheric connectivity but unaltered interhemispheric connectivity. The disrupted functional connectivity was most pronounced on the day of the onset of symptoms, with a subsequent return toward normal during the course of recovery. This time course was found to differ between the selected parts of the facial motor network. However, the increase in functional connectivity strength preceded clinical recovery in all areas and reached a stable level before the patient fully recovered. CONCLUSION: . These results demonstrate that recovery from facial nerve palsy is complemented by cortical reorganization, with pronounced changes of functional connectivity that precede clinical recovery.
Lin, C. H., C. Wallace, et al. (2011). "Functioning Free Gracilis Myocutaneous Flap Transfer Provides a Reliable Single-Stage Facial Reconstruction and Reanimation following Tumor Ablation." Plast Reconstr Surg 128(3): 687-696.
BACKGROUND: : Ablative orofacial defects incorporating mimetic facial musculature/nerve cause hemifacial expressive dysfunction and considerable morbidity but are rarely reanimated immediately using free functioning gracilis myocutaneous flaps. METHODS: : Disrupted buccal branches provided a recipient facial nerve for 24 gracilis reinnervations. An additional 15 free flaps were used for extensive composite defects. Smile outcome was graded according to Terzis' criteria after 2 years of recurrence-free follow-up. The effects of postoperative radiotherapy, integrity of the oral commissure, and double free flaps were compared. RESULTS: : Eighteen patients completed 2 years' recurrence-free follow-up; average smile outcome was Terzis grade 4 (mean, 3.8). Resection/reconstruction of the modiolus (five of 18 patients) tended to diminish outcome (Terzis grade 3, mean, 3.0; median, 3; versus Terzis grade 4, mean, 4.1; median, 5) compared with two free flaps performed simultaneouly (mean, 3.56 versus 4.14; median, 3 versus 5). Postoperative radiotherapy (eight of 18 patients) had a more modest effect on outcome (Terzis grade 3, mean, 3.3; Terzis grade 4, mean, 4.1; median, 3 versus 5). CONCLUSION: : Reconstruction of oncologic defects including expressive facial musculature/nerve with gracilis free functioning muscle transfer can restore oral continence and facial expression primarily. CLINICAL QUESTION/LEVEL OF EVIDENCE:: Therapeutic, IV. Clapham, L., S. Thomas, et al. (2011). "Facial muscle contraction in response to mechanical stretch after severe facial nerve injury: Clapham's sign." J Laryngol Otol 125(7): 732-737.
INTRODUCTION: Following the onset of facial palsy, physiotherapists routinely inspect the inside of the patient's mouth and cheek for complications such as ulceration or trauma. In several patients with complete facial nerve palsy, it was noticed that when the cheek was stretched there was subsequent spasm of the muscles of facial expression. This also occurred in patients whose facial nerve had been transected. CASE REPORTS: We present four patients in whom this response was demonstrated. We consider the mechanism of this response and its relevance in the management of patients with facial paralysis. CONCLUSION: Following severe or complete denervation, contraction of the facial muscles following mechanical stretch provides evidence of preservation of activity in the facial muscle's excitation-contraction apparatus. Further research will investigate the clinical significance of this sign and whether it can be used as an early predicator of the development of synkinesis, as well as its relevance to facial nerve grafting and repair.
Griffin, G. R. and J. C. Kim (2011). "Potential of an electric prosthesis for dynamic facial reanimation." Otolaryngol Head Neck Surg 145(3): 365-368.
Chronic facial paralysis is a devastating condition with severe functional and emotional consequences. The current surgical armamentarium permits the predictable reestablishment of a protective blink as well as good resting symmetry. Yet the ultimate goal of symmetric, spontaneous emotional expression remains elusive despite significant progress in the areas of peripheral nerve grafting and free tissue transfer. This commentary explores the possibility of an implantable electrical prosthesis for facial reanimation. It reviews animal studies supporting this concept as well as recent human data suggesting that such an implant could rescue denervated facial musculature, thus overcoming a major hurdle for existing reanimation techniques.