In this study, atomic force microscopy-based dynamic oscillatory and force-relaxation indentation was employed to quantify the time-dependent nanomechanics of native (untreated) and proteoglycan (PG)-depleted cartilage disks, including indentation modulus E(ind), force-relaxation time constant τ, magnitude of dynamic complex modulus |E(∗)|, phase angle δ between force and indentation depth, storage modulus E', and loss modulus E″. At ∼2 nm dynamic deformation amplitude, |E(∗)| increased significantly with frequency from 0.22 ± 0.02 MPa (1 Hz) to 0.77 ± 0.10 MPa (316 Hz), accompanied by an increase in δ (energy dissipation). At this length scale, the energy dissipation mechanisms were deconvoluted: the dynamic frequency dependence was primarily governed by the fluid-flow-induced poroelasticity, whereas the long-time force relaxation reflected flow-independent viscoelasticity. After PG depletion, the change in the frequency response of |E(∗)| and δ was consistent with an increase in cartilage local hydraulic permeability. Although untreated disks showed only slight dynamic amplitude-dependent behavior, PG-depleted disks showed great amplitude-enhanced energy dissipation, possibly due to additional viscoelastic mechanisms. Hence, in addition to functioning as a primary determinant of cartilage compressive stiffness and hydraulic permeability, the presence of aggrecan minimized the amplitude dependence of |E(∗)| at nanometer-scale deformation.

Facial nerve injury can cause severe long-term physical and psychological morbidity. There are limited repair options for an acutely transected facial nerve not amenable to primary neurorrhaphy. We hypothesize that a peptide amphiphile nanofiber neurograft may provide the nanostructure necessary to guide organized neural regeneration. Five experimental groups were compared, animals with (1) an intact nerve, (2) following resection of a nerve segment, and following resection and immediate repair with either a (3) autograft (using the resected nerve segment), (4) neurograft, or (5) empty conduit. The buccal branch of the rat facial nerve was directly stimulated with charge balanced biphasic electrical current pulses at different current amplitudes whereas nerve compound action potentials (nCAPs) and electromygraphic responses were recorded. After 8 weeks, the proximal buccal branch was surgically reexposed and electrically evoked nCAPs were recorded for groups 1-5. As expected, the intact nerves required significantly lower current amplitudes to evoke an nCAP than those repaired with the neurograft and autograft nerves. For other electrophysiologic parameters such as latency and maximum nCAP, there was no significant difference between the intact, autograft, and neurograft groups. The resected group had variable responses to electrical stimulation, and the empty tube group was electrically silent. Immunohistochemical analysis and transmission electron microscopy confirmed myelinated neural regeneration. This study demonstrates that the neuroregenerative capability of peptide amphiphile nanofiber neurografts is similar to the current clinical gold standard method of repair and holds potential as an off-the-shelf solution for facial reanimation and potentially peripheral nerve repair.

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Objectives: Facial palsy causes variable facial disfigurement ranging from subtle asymmetry to crippling deformity. There is no existing standard database to serve as a resource for facial palsy education and research. We present a standardized set of facial photographs and videos representing the entire spectrum of flaccid and nonflaccid (aberrantly regenerated or synkinetic) facial palsy. To demonstrate the utility of the dataset, we describe the relationship between level of facial function and perceived emotion expression as determined by an automated emotion detection, machine learning-based algorithm.Methods: Photographs and videos of patients with both flaccid and nonflaccid facial palsy were prospectively gathered. The degree of facial palsy was quantified using eFACE, House-Brackmann, and Sunnybrook scales. Perceived emotion during a standard video of facial movements was determined using an automated, machine learning algorithm.Results: Sixty participants were enrolled and categorized by eFACE score across the range of facial function. Patients with complete flaccid facial palsy (eFACE <60) had a significant loss of perceived joy compared to the nonflaccid and normal groups. Additionally, patients with only moderate flaccid and nonflaccid facial palsy had a significant increase in perceived negative emotion (contempt) when compared to the normal group.Conclusion:We provide this open-source database to assist in comparing current and future scales of facial function as well as facilitate comprehensive investigation of the entire spectrum of facial palsy. The automated machine learning-based algorithm detected negative emotions at moderate levels of facial palsy and suggested a threshold severity of flaccid facial palsy beyond which joy was not perceived.

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Introduction Facial nerve palsy results in both functional disability and psychological morbidity. There are several well-established grading scales to quantify the quality of life of these patients. Objective Translate and validate the Facial Clinimetric Evaluation (FaCE) scale and Synkinesis Assessment Questionnaire (SAQ) to Brazilian Portuguese. Methods This study adopted a forward-backward translation method and performed cross-cultural adaptation. A pilot study was conducted to correct any confusing language and to evaluate content validity. A validation study was then performed. Internal consistency of the Brazilian Portuguese version of the FaCE and SAQ items was evaluated by Cronbach’s alpha coefficient. Construct validity was assessed by Spearman’s Rank Correlation Coefficient between FaCE and SAQ scores to eFACE, House-Brackmann, Short Form 12 (SF-12) and Facial Disability Index (FDI) (sub)scores. Results A total of 90 patients were included. Cronbach’s alpha for total domain scored 0.881 for FaCE and 0.809 for SAQ. FaCE total score correlation to eFACE total and House-Brackmann showed Spearman’s r value of 0.537 and −0.538, respectively (p < 0.001). SAQ correlation to eFACE synkinesis subdomain was −0.449 (p < 0.001). No correlation was found between SAQ and HB score. FaCE total score correlations were of 0.301 and 0.547 for SF-12 PCS and MCS, respectively (p < 0.001). Correlation between FaCE total and FDI Physical and Social/well-being functions were 0.498 and 0.567 (p < 0.001). Conclusion Brazilian Portuguese FaCE scale and SAQ versions achieved high validity and reliability in the present study. These translated instruments demonstrated good psychometric properties, being proper to use in clinical practice in Brazil and with Brazilian Portuguese speakers.

Purpose of review The purpose of this review is to summarize best practices in facial nerve management for patients with head and neck cancer. In addition, we provide a review of recent literature on novel innovations and techniques in facial reanimation surgery. Recent findings Although recommended when tumor ablation surgery requires facial nerve sacrifice, facial reanimation procedures are not always performed. Concurrent dynamic facial reanimation with masseteric nerve transfers and cable graft repair can preserve native facial muscle function. Static suspension can provide facial support and immediate resting symmetry for patients. Eyelid weight and eye care should not be delayed, particularly in patients with trigeminal sensory deficits. Choice of neural source to innervate a gracilis-free muscle transfer for smile reanimation remains controversial; however, new techniques, such as dual innervation and multivector muscle transfer, may improve aesthetic and functional outcomes. Summary Management of the facial nerve in the setting of head and neck cancer presents unique challenges. When possible, simultaneous oncologic resection and facial reanimation is ideal given the open surgical field, newly dissected and electrically stimulatable facial nerve branches, as well as minimizing postoperative healing time to prevent postsurgical treatment delays. A coordinated approach to facial nerve management with a multidisciplinary surgical team may help provide optimal, comprehensive care.

Background: A rare subset of sarcoidosis, neurosarcoidosis, is reported to occur in 5-7% of sarcoid patients and can manifest in a variety of ways. The most common are facial paralysis and optic neuritis, less commonly causing cochleovestibulopathy, blindness, anosmia, and other cranial nerve (CN) palsies. The sensory deficit may be severe and psychiatric symptoms may result from the effects of the disease or steroid treatment. Although MRI-compatible cochlear implants are now available, concerns about the feasibility of recoverable hearing with cochlear implantation in these patients as well as the practical difficulty of disease monitoring due to implant artifact must be considered. Results: We present 3 recent cases from different institutions. The first is a 39-year-old man with a history of progressively worsening hearing loss, followed by visual loss, delusions, agitation, ataxia, and musical auditory hallucinations, diffuse leptomeningeal enhancement on MRI with a normal serum angiotensin-converting enzyme (ACE) level but elevated cerebrospinal fluid (CSF) ACE levels, suggesting neurosarcoidosis, was treated with corticosteroids, and underwent successful cochlear implantation. The second is a 36-year-old woman with rapid-onset horizontal diplopia, left mixed severe sensorineural hearing loss (SNHL) and tinnitus, diffuse leptomeningeal enhancement on MRI, and progressive palsy of the left CNs IV, VI, VII, IX, X and XI, with altered mental status requiring admission following high-dose intravenous corticosteroids. The third is a 15-year-old boy who presented with sudden, bilateral, profound SNHL, recurrent headaches, and left facial weakness refractory to antivirals, ultimately diagnosed with neurosarcoidosis following an aborted cochlear implantation where diffuse inflammation was found, and histopathology revealed Schaumann bodies; he was treated with methotrexate and later underwent successful cochlear implantation. Conclusions: Neurosarcoidosis is an elusive diagnosis and can cause hearing loss and psychiatric symptoms. Cochlear implantation for patients with severe hearing loss should be considered once the diagnosis is confirmed, as it is possible to achieve a successful level of hearing. Psychiatric symptoms can manifest with the onset of neurosarcoidosis, result from CN deficits, or develop as a side effect from long-term, high-dose corticosteroids, and should be monitored carefully in patients with neurosarcoidosis.