Worldwide Prevalence of Antibiotic-Associated Stevens-Johnson Syndrome and Toxic Epidermal Necrolysis: A Systematic Review and Meta-analysis.

Importance: Antibiotics are an important risk for Stevens-Johnson syndrome and toxic epidermal necrolysis (SJS/TEN), which are the most severe types of drug hypersensitivity reaction with a mortality rate up to 50%. To our knowledge, no global systematic review has described antibiotic-associated SJS/TEN. Objective: To evaluate the prevalence of antibiotics associated with SJS/TEN worldwide. Data Sources: The MEDLINE and Embase databases were searched for experimental and observational studies that described SJS/TEN risks since database inception to February 22, 2022. Study Selection: Included studies adequately described SJS/TEN origins and specified the antibiotics associated with SJS/TEN. Data Extraction and Synthesis: Two reviewers (E.Y.L. and C.K.) independently selected the studies, extracted the data, and assessed the risk of bias. A meta-analysis using a random-effects model was performed in the studies that described patient-level associations. Subgroup analyses were performed to explore the heterogeneity. The risk of bias was assessed using the Joanna Briggs Institute checklist, and the certainty of evidence was rated using the GRADE (Grading of Recommendations Assessment, Development and Evaluation) approach. Main Outcomes and Measures: Prevalence of antibiotic-associated SJS/TEN was presented as pooled proportions with 95% CIs. Results: Among the 64 studies included in the systematic review, there were 38 studies that described patient-level associations; the meta-analysis included these 38 studies with 2917 patients to determine the prevalence of single antibiotics associated with SJS/TEN. The pooled proportion of antibiotics associated with SJS/TEN was 28% (95% CI, 24%-33%), with moderate certainty of evidence. Among antibiotic-associated SJS/TEN, the sulfonamide class was associated with 32% (95% CI, 22%-44%) of cases, followed by penicillins (22%; 95% CI, 17%-28%), cephalosporins (11%; 95% CI, 6%-17%), fluoroquinolones (4%; 95% CI, 1%-7%), and macrolides (2%; 95% CI, 1%-5%). There was a statistically significant heterogeneity in the meta-analysis, which could be partially explained in the subgroup analysis by continents. The overall risk of bias was low using the Joanna Briggs Institute checklist for case series. Conclusion and Relevance: In this systematic review and meta-analysis of all case series, antibiotics were associated with more than one-quarter of SJS/TEN cases described worldwide, and sulfonamide antibiotics remained the most important association. These findings highlight the importance of antibiotic stewardship, clinician education and awareness, and weighing the risk-benefit assessment of antibiotic choice and duration.

Genetic architecture of multiple mutualisms and mating system in Turnera ulmifolia.

Plants often associate with multiple arthropod mutualists. These partners provide important services to their hosts, but multiple interactions can constrain a plant's ability to respond to complex, multivariate selection. Here, we quantified patterns of genetic variance and covariance among rewards for pollination, biotic defence and seed dispersal mutualisms in multiple populations of Turnera ulmifolia to better understand how the genetic architecture of multiple mutualisms might influence their evolution. We phenotyped plants cultivated from 17 Jamaican populations for several mutualism and mating system-related traits. We then fit genetic variance-covariance (G) matrices for the island metapopulation and the five largest individual populations. At the metapopulation level, we observed significant positive genetic correlations among stigma-anther separation, floral nectar production and extrafloral nectar production. These correlations have the potential to significantly constrain or facilitate the evolution of multiple mutualisms in T. ulmifolia and suggest that pollination, seed dispersal and defence mutualisms do not evolve independently. In particular, we found that positive genetic correlations between floral and extrafloral nectar production may help explain their stable coexistence in the face of physiological trade-offs and negative interactions between pollinators and ant bodyguards. Locally, we found only small differences in G among our T. ulmifolia populations, suggesting that geographic variation in G may not shape the evolution of multiple mutualisms.

Toward the Bionic Face: A Novel Neuroprosthetic Device Paradigm for Facial Reanimation Consisting of Neural Blockade and Functional Electrical Stimulation.

BACKGROUND: Facial palsy is a devastating condition potentially amenable to rehabilitation by functional electrical stimulation. Herein, a novel paradigm for unilateral facial reanimation using an implantable neuroprosthetic device is proposed and its feasibility demonstrated in a live rodent model. The paradigm comprises use of healthy-side electromyographic activity as control inputs to a system whose outputs are neural stimuli to effect symmetric facial displacements. The vexing issue of suppressing undesirable activity resulting from aberrant neural regeneration (synkinesis) or nerve transfer procedures is addressed using proximal neural blockade. METHODS: Epimysial and nerve cuff electrode arrays were implanted in the faces of Wistar rats. Stimuli were delivered to evoke blinks and whisks of various durations and amplitudes. The dynamic relation between electromyographic signals and facial displacements was modeled, and model predictions were compared against measured displacements. Optimal parameters to achieve facial nerve blockade by means of high-frequency alternating current were determined, and the safety of continuous delivery was assessed. RESULTS: Electrode implantation was well tolerated. Blinks and whisks of tunable amplitudes and durations were evoked by controlled variation of neural stimuli parameters. Facial displacements predicted from electromyographic input modelling matched those observed with a variance-accounted-for exceeding 96 percent. Effective and reversible facial nerve blockade in awake behaving animals was achieved, without detrimental effect noted from long-term continual use. CONCLUSIONS: Proof-of-principle of rehabilitation of hemifacial palsy by means of a neuroprosthetic device has been demonstrated. The use of proximal neural blockade coupled with distal functional electrical stimulation may have relevance to rehabilitation of other peripheral motor nerve deficits.

Recruitment and retention of participants in randomised controlled trials: a review of trials funded and published by the United Kingdom Health Technology Assessment Programme.

BACKGROUND: Substantial amounts of public funds are invested in health research worldwide. Publicly funded randomised controlled trials (RCTs) often recruit participants at a slower than anticipated rate. Many trials fail to reach their planned sample size within the envisaged trial timescale and trial funding envelope. OBJECTIVES: To review the consent, recruitment and retention rates for single and multicentre randomised control trials funded and published by the UK's National Institute for Health Research (NIHR) Health Technology Assessment (HTA) Programme. DATA SOURCES AND STUDY SELECTION: HTA reports of individually randomised single or multicentre RCTs published from the start of 2004 to the end of April 2016 were reviewed. DATA EXTRACTION: Information was extracted, relating to the trial characteristics, sample size, recruitment and retention by two independent reviewers. MAIN OUTCOME MEASURES: Target sample size and whether it was achieved; recruitment rates (number of participants recruited per centre per month) and retention rates (randomised participants retained and assessed with valid primary outcome data). RESULTS: This review identified 151 individually RCTs from 787 NIHR HTA reports. The final recruitment target sample size was achieved in 56% (85/151) of the RCTs and more than 80% of the final target sample size was achieved for 79% of the RCTs (119/151). The median recruitment rate (participants per centre per month) was found to be 0.92 (IQR 0.43-2.79) and the median retention rate (proportion of participants with valid primary outcome data at follow-up) was estimated at 89% (IQR 79-97%). CONCLUSIONS: There is considerable variation in the consent, recruitment and retention rates in publicly funded RCTs. Investigators should bear this in mind at the planning stage of their study and not be overly optimistic about their recruitment projections.

The effects of venous ensheathment on facial nerve repair in the rat.

OBJECTIVE: To investigate the protective effect of autologous venous ensheathment on sutured rat facial nerve and to test whether the ensheathment could improve the functional recovery of repaired nerve and accuracy of axonal growth. STUDY DESIGN: In vivo study. METHODS: Forty-six rats were examined, with six rats serving as normal controls and 40 receiving facial nerve transection and suture repair (SR) or transection and suture repair with an additional venous ensheathment (VE). The rats were then subjected to functional testing, histological assessment of nerve specimens, or retrograde tracing, respectively. RESULTS: At the postoperative day (POD) 60, the venous ensheathment showed no adhesion at the surrounding tissues. No significant difference in neuroma formation was found between the two surgical manipulations (SR and VE groups) (P < 0.05). Retrogradely labeled motoneurons in facial nuclei were extremely disorganized after the facial nerve undertook surgical manipulation. In all manipulated groups, double retrogradely labeled neurons, indicative of aberrant axonal branching during regeneration, could be observed after peripheral manipulation across all time points. With the two facial surgical manipulations, the average count of double-labeled neurons at POD 60 was significantly less than at POD 21 (P < 0.05). CONCLUSION: Autologous venous ensheathment could not help with the functional recovery of facial nerve or improve the accuracy of axonal regeneration. Further studies are warranted to elucidate the effects of venous ensheathment in other motor and sensory nerve models. LEVEL OF EVIDENCE: NA. Laryngoscope, 127:1558-1564, 2017.

Bilateral Facial Paralysis: A 13-Year Experience.

BACKGROUND: Bilateral facial palsy is a rare clinical entity caused by myriad disparate conditions requiring different treatment paradigms. Lyme disease, Guillain-Barré syndrome, and leukemia are several examples. In this article, the authors describe the cause, the initial diagnostic approach, and the management of long-term sequelae of bilateral paralysis that has evolved in the authors' center over the past 13 years. METHODS: A chart review was performed to identify all patients diagnosed with bilateral paralysis at the authors' center between January of 2002 and January of 2015. Demographics, signs and symptoms, diagnosis, initial medical treatment, interventions for facial reanimation, and outcomes were reviewed. RESULTS: Of the 2471 patients seen at the authors' center, 68 patients (3 percent) with bilateral facial paralysis were identified. Ten patients (15 percent) presented with bilateral facial paralysis caused by Lyme disease, nine (13 percent) with Möbius syndrome, nine (13 percent) with neurofibromatosis type 2, five (7 percent) with bilateral facial palsy caused by brain tumor, four (6 percent) with Melkersson-Rosenthal syndrome, three (4 percent) with bilateral temporal bone fractures, two (3 percent) with Guillain-Barré syndrome, one (2 percent) with central nervous system lymphoma, one (2 percent) with human immunodeficiency virus infection, and 24 (35 percent) with presumed Bell palsy. Treatment included pharmacologic therapy, physical therapy, chemodenervation, and surgical interventions. CONCLUSIONS: Bilateral facial palsy is a rare medical condition, and treatment often requires a multidisciplinary approach. The authors outline diagnostic and therapeutic algorithms of a tertiary care center to provide clinicians with a systematic approach to managing these complicated patients.

The Dilator Naris Muscle as a Reporter of Facial Nerve Regeneration in a Rat Model.

OBJECTIVE: Many investigators study facial nerve regeneration using the rat whisker pad model, although widely standardized outcomes measures of facial nerve regeneration in the rodent have not yet been developed. The intrinsic whisker pad "sling" muscles producing whisker protraction, situated at the base of each individual whisker, are extremely small and difficult to study en bloc. Here, we compare the functional innervation of 2 potential reporter muscles for whisker pad innervation: the dilator naris (DN) and the levator labii superioris (LLS), to characterize facial nerve regeneration. METHODS: Motor supply of the DN and LLS was elucidated by measuring contraction force and compound muscle action potentials during stimulation of individual facial nerve branches, and by measuring whisking amplitude before and after DN distal tendon release. RESULTS: The pattern of DN innervation matched that of the intrinsic whisker pad musculature (ie, via the buccal and marginal mandibular branches of the facial nerve), whereas the LLS seemed to be innervated almost entirely by the zygomatic branch, whose primary target is the orbicularis oculi muscle. CONCLUSIONS: Although the LLS has been commonly used as a reporter muscle of whisker pad innervation, the present data show that its innervation pattern does not overlap substantially with the muscles producing whisker protraction. The DN muscle may serve as a more appropriate reporter for whisker pad innervation because it is innervated by the same facial nerve branches as the intrinsic whisker pad musculature, making structure/function correlations more accurate, and more relevant to investigators studying facial nerve regeneration.

Long-term functional recovery after facial nerve transection and repair in the rat.

BACKGROUND: The rodent model is commonly used to study facial nerve injury. Because of the exceptional regenerative capacity of the rodent facial nerve, it is essential to consider the timing when studying facial nerve regeneration and functional recovery. Short-term functional recovery data following transection and repair of the facial nerve has been documented by our laboratory. However, because of the limitations of the head fixation device, there is a lack of long-term data following facial nerve injury. The objective of this study was to elucidate the long-term time course and functional deficit following facial nerve transection and repair in a rodent model. METHODS: Adult rats were divided into group 1 (controls) and group 2 (experimental). Group 1 animals underwent head fixation, followed by a facial nerve injury, and functional testing was performed from day 7 to day 70. Group 2 animals underwent facial nerve injury, followed by delayed head fixation, and then underwent functional testing from months 6 to 8. RESULTS: There was no statistical difference between the average whisking amplitudes in group 1 and group 2 animals. CONCLUSION: Functional whisking recovery 6 months after facial nerve injury is comparable to recovery within 1 to 4 months of transection and repair, thus the ideal window for evaluating facial nerve recovery falls within the 4 months after injury.

Ankle Injury Management (AIM): design of a pragmatic multi-centre equivalence randomised controlled trial comparing Close Contact Casting (CCC) to Open surgical Reduction and Internal Fixation (ORIF) in the treatment of unstable ankle fractures in patients over 60 years.

BACKGROUND: Ankle fractures account for 9% of all fractures with a quarter of these occurring in adults over 60 years. The short term disability and long-term consequences of this injury can be considerable. Current opinion favours open reduction and internal fixation (ORIF) over non-operative treatment (fracture manipulation and the application of a standard moulded cast) for older people. Both techniques are associated with complications but the limited published research indicates higher complication rates of fracture malunion (poor position at healing) with casting. The aim of this study is to compare ORIF with a modification of existing casting techniques, Close Contact Casting (CCC). We propose that CCC may offer an equivalent functional outcome to ORIF and avoid the risks associated with surgery. METHODS/DESIGN: This study is a pragmatic multi-centre equivalence randomised controlled trial. 620 participants will be randomised to receive ORIF or CCC after sustaining an isolated displaced unstable ankle fracture. Participants will be recruited from a minimum of 20 National Health Service (NHS) acute hospitals throughout England and Wales. Participants will be aged over 60 years and be ambulatory prior to injury. Follow-up will be at six weeks and six months after randomisation. The primary outcome is the Olerud & Molander Ankle Score, a functional patient reported outcome measure, at 6 months. Follow-up will also include assessments of mobility, ankle range of movement, health related quality of life and complications. The six-month follow-up will be conducted face-to-face by an assessor blinded to the allocated intervention. A parallel economic evaluation will consider both a health service and a broader societal perspective including the individual and their family. In order to explore patient experience of their treatment and recovery, a purposive sample of 40 patients will also be interviewed using a semi-structured interview schedule between 6-10 weeks post treatment. DISCUSSION: This multicentre study was open to recruitment July 2010 and recruitment is due to be completed in December 2013. TRIAL REGISTRATION: Current Controlled Trials ISRCTN04180738.

Rat whisker movement after facial nerve lesion: evidence for autonomic contraction of skeletal muscle.

Vibrissal whisking is often employed to track facial nerve regeneration in rats; however, we have observed similar degrees of whisking recovery after facial nerve transection with or without repair. We hypothesized that the source of non-facial nerve-mediated whisker movement after chronic denervation was from autonomic, cholinergic axons traveling within the infraorbital branch of the trigeminal nerve (ION). Rats underwent unilateral facial nerve transection with repair (N=7) or resection without repair (N=11). Post-operative whisking amplitude was measured weekly across 10weeks, and during intraoperative stimulation of the ION and facial nerves at ⩾18weeks. Whisking was also measured after subsequent ION transection (N=6) or pharmacologic blocking of the autonomic ganglia using hexamethonium (N=3), and after snout cooling intended to elicit a vasodilation reflex (N=3). Whisking recovered more quickly and with greater amplitude in rats that underwent facial nerve repair compared to resection (P<0.05), but individual rats overlapped in whisking amplitude across both groups. In the resected rats, non-facial-nerve-mediated whisking was elicited by electrical stimulation of the ION, temporarily diminished following hexamethonium injection, abolished by transection of the ION, and rapidly and significantly (P<0.05) increased by snout cooling. Moreover, fibrillation-related whisker movements decreased in all rats during the initial recovery period (indicative of reinnervation), but re-appeared in the resected rats after undergoing ION transection (indicative of motor denervation). Cholinergic, parasympathetic axons traveling within the ION innervate whisker pad vasculature, and immunohistochemistry for vasoactive intestinal peptide revealed these axons branching extensively over whisker pad muscles and contacting neuromuscular junctions after facial nerve resection. This study provides the first behavioral and anatomical evidence of spontaneous autonomic innervation of skeletal muscle after motor nerve lesion, which not only has implications for interpreting facial nerve reinnervation results, but also calls into question whether autonomic-mediated innervation of striated muscle occurs naturally in other forms of neuropathy.

Whisking recovery after automated mechanical stimulation during facial nerve regeneration.

IMPORTANCE Recovery from facial nerve transection is typically poor, but daily mechanical stimulation of the face in rats has been reported to remarkably enhance functional recovery after facial nerve transection and suture repair. This phenomenon needs additional investigation because of its important clinical implications. OBJECTIVE To determine whether automated mechanical stimulation of the whisker pad improves whisking recovery after facial nerve transection and repair in a rat model. DESIGN AND SETTING Sixty-one rats underwent unilateral facial nerve transection and suture repair and were randomized into 8 groups. Six groups received daily automated whisker or whisker pad mechanical stimulation including 0.5-, 1.5-, and 8.0-Hz patterns. Two control groups received restraint without stimulation. Treatment started on postoperative day 8, occurred 5 days per week, and lasted throughout 15 weeks of recovery. Whisking amplitude, velocity, and acceleration were quantified weekly for 15 weeks. INTERVENTIONS Unilateral facial nerve transection, suture repair, and, for 6 groups, daily automated whisker or whisker pad mechanical stimulation. MAIN OUTCOMES AND MEASURES Quantification of whisking amplitude, velocity, and acceleration. RESULTS Rats receiving the low frequencies of stimulation of the whiskers or whisker pad did not demonstrate enhanced whisking recovery, and rats receiving stimulation at 8.0 Hz showed significantly worse whisking recovery compared with controls and previously published groups receiving lower dose manual stimulation. CONCLUSIONS AND RELEVANCE Although daily manual whisker pad stimulation has been shown to enhance whisking recovery, rats in this study did not demonstrate improved whisking recovery after automated mechanical stimulation across a wide range of driving frequencies. Moreover, faster stimulation (8.0 Hz) was actually detrimental to recovery. Further work is needed to understand the relationship between stimulation patterns and the physiologic mechanisms underlying improved or worsened functional outcomes after facial nerve transection and repair.

Treatment compliance and effectiveness of a cognitive behavioural intervention for low back pain: a complier average causal effect approach to the BeST data set.

BACKGROUND: Group cognitive behavioural intervention (CBI) is effective in reducing low-back pain and disability in comparison to advice in primary care. The aim of this analysis was to investigate the impact of compliance on estimates of treatment effect and to identify factors associated with compliance. METHODS: In this multicentre trial, 701 adults with troublesome sub-acute or chronic low-back pain were recruited from 56 general practices. Participants were randomised to advice (control n = 233) or advice plus CBI (n = 468). Compliance was specified a priori as attending a minimum of three group sessions and the individual assessment. We estimated the complier average causal effect (CACE) of treatment. RESULTS: Comparison of the CACE estimate of the mean treatment difference to the intention-to-treat (ITT) estimate at 12 months showed a greater benefit of CBI amongst participants compliant with treatment on the Roland Morris Questionnaire (CACE: 1.6 points, 95% CI 0.51 to 2.74; ITT: 1.3 points, 95% CI 0.55 to 2.07), the Modified Von Korff disability score (CACE: 12.1 points, 95% CI 6.07 to 18.17; ITT: 8.6 points, 95% CI 4.58 to 12.64) and the Modified von Korff pain score (CACE: 10.4 points, 95% CI 4.64 to 16.10; ITT: 7.0 points, 95% CI 3.26 to 10.74). People who were non-compliant were younger and had higher pain scores at randomisation. CONCLUSIONS: Treatment compliance is important in the effectiveness of group CBI. Younger people and those with more pain are at greater risk of non-compliance. TRIAL REGISTRATION: Current Controlled Trials ISRCTN54717854.

Functional recovery after facial nerve cable grafting in a rodent model.

IMPORTANCE: Cable grafting is widely considered to be the preferred alternative to primary repair of the injured facial nerve; however, quantitative comparison of the 2 techniques has not been previously undertaken in a rodent model. OBJECTIVE: To establish functional recovery parameters after interposition autografting in a rodent facial nerve model. DESIGN, SETTING, AND PARTICIPANTS: Prospective randomized animal study at a tertiary care facial nerve center using 16 female Wistar Hannover rats. INTERVENTION: The experimental group received reversed autograft reconstruction of a 20-mm neural gap, and the control group received facial nerve transection and primary repair. MAIN OUTCOME AND MEASURE: Whisker excursion was measured weekly for 70 postoperative days using laser micrometers. RESULTS: The control group exhibited the most rapid recovery, with substantial return of whisker movement occurring during the third postoperative week. The experimental group demonstrated return of function beginning in the fourth postoperative week, eventually achieving a degree of function comparable to that of the control group by the sixth postoperative week (P = .68). CONCLUSIONS AND RELEVANCE: Recovery of facial function after cable grafting seems to be slower than, but eventually similar to, recovery after primary neurorrhaphy in a rodent model. In the present study we have established a benchmark for recovery of whisker movement across a 20-mm rodent facial nerve gap, which will be used for comparison of different facial nerve gap bridging materials in future studies. LEVEL OF EVIDENCE: NA.

A system for delivering mechanical stimulation and robot-assisted therapy to the rat whisker pad during facial nerve regeneration.

Functional recovery is typically poor after facial nerve transection and surgical repair. In rats, whisking amplitude remains greatly diminished after facial nerve regeneration, but can recover more completely if the whiskers are periodically mechanically stimulated during recovery. Here we present a robotic "whisk assist" system for mechanically driving whisker movement after facial nerve injury. Movement patterns were either preprogrammed to reflect natural amplitudes and frequencies, or movements of the contralateral (healthy) side of the face were detected and used to control real-time mirror-like motion on the denervated side. In a pilot study, 20 rats were divided into nine groups and administered one of eight different whisk assist driving patterns (or control) for 5-20 minutes, five days per week, across eight weeks of recovery after unilateral facial nerve cut and suture repair. All rats tolerated the mechanical stimulation well. Seven of the eight treatment groups recovered average whisking amplitudes that exceeded controls, although small group sizes precluded statistical confirmation of group differences. The potential to substantially improve facial nerve recovery through mechanical stimulation has important clinical implications, and we have developed a system to control the pattern and dose of stimulation in the rat facial nerve model.

Quantitative analysis of muscle histologic method in rodent facial nerve injury.

OBJECTIVE: To describe denervation features of facial musculature following facial nerve injury in a rodent model. METHODS: Six Wistar-Hannover rats underwent unilateral transection and immediate repair of the facial nerve. After 8 weeks, muscular bundles consisting of dilator naris and levator labii superioris from both sides were analyzed for mean muscle cell diameter and the percentage of muscle cell cross-sectional area using image processing software. The atrophic features of facial muscles were quantified and compared with the contralateral, healthy side of the face. RESULTS: Weekly postoperative whisking assessment demonstrated the anticipated course of recovery. We observed significant differences between the normal side and the manipulated side, respectively, in the percentage of muscle specimen cross-sectional area attributable to muscle cell profiles (57% vs 29%; P = .006) and total fiber counts (1346 vs 794; P = .02). The mean cross-sectional area of individual muscle fibers was higher on the normal side (1129 vs 928 µm2; P = .39); however, this difference was statistically nonsignificant. CONCLUSION: The objective, quantitative measures of muscle microstructure used in this report provide a valuable point of comparison for whisking function and electrophysiologic measures and can be used in future studies to assess muscle atrophic features associated with facial nerve injury and repair techniques.

Facial nerve repair: fibrin adhesive coaptation versus epineurial suture repair in a rodent model.

OBJECTIVES/HYPOTHESIS: Repair of the transected facial nerve has traditionally been accomplished with microsurgical neurorrhaphy; however, fibrin adhesive coaptation (FAC) of peripheral nerves has become increasingly popular over the past decade. We compared functional recovery following suture neurorrhaphy to FAC in a rodent facial nerve model. STUDY DESIGN: Prospective, randomized animal study. METHODS: Sixteen rats underwent transection and repair of the facial nerve proximal to the pes anserinus. Eight animals underwent epineurial suture (ES) neurorrhaphy, and eight underwent repair with fibrin adhesive (FA). Surgical times were documented for all procedures. Whisking function was analyzed on a weekly basis for both groups across 15 weeks of recovery. RESULTS: Rats experienced whisking recovery consistent in time course and degree with prior studies of rodent facial nerve transection and repair. There were no significant differences in whisking amplitude, velocity, or acceleration between suture and FA groups. However, the neurorrhaphy time with FA was 70% shorter than for ES (P < 0.05). CONCLUSION: Although we found no difference in whisking recovery between suture and FA repair of the main trunk of the rat facial nerve, the significantly shorter operative time for FA repair makes this technique an attractive option. The relative advantages of both techniques are discussed.

Use of X-ray diffraction, molecular simulations, and spectroscopy to determine the molecular packing in a polymer-fullerene bimolecular crystal.

The molecular packing in a polymer: fullerene bimolecular crystal is determined using X-ray diffraction (XRD), molecular mechanics (MM) and molecular dynamics (MD) simulations, 2D solid-state NMR spectroscopy, and IR absorption spectroscopy. The conformation of the electron-donating polymer is significantly disrupted by the incorporation of the electron-accepting fullerene molecules, which introduce twists and bends along the polymer backbone and 1D electron-conducting fullerene channels.

The convergence of facial nerve branches providing whisker pad motor supply in rats: implications for facial reanimation study.

INTRODUCTION: Rodent whisking behavior is supported by the buccal and mandibular branches of the facial nerve, but a description of how these branches converge and contribute to whisker movement is lacking. METHODS: Eight rats underwent isolated transection of either the buccal or mandibular branch and subsequent opposite branch transection. Whisking function was analyzed after both transections. Anatomical measurements, and video recording of stimulation to individual branches, were taken from both facial nerves in 10 rats. RESULTS: Normal to near-normal whisking was demonstrated after isolated branch transection. Whisking was eliminated after transection of both branches. The buccal and mandibular branches form a convergence just proximal to the whisker pad, herein called "distal pes." Distal to this convergence, we identified consistent anatomy that demonstrated cross-innervation. CONCLUSION: The overlap of efferent supply to the whisker pad must be considered when studying facial nerve regeneration in the rat facial nerve model.

The effects of potential neuroprotective agents on rat facial function recovery following facial nerve injury.

OBJECTIVE: To evaluate whether a series of pharmacologic agents with potential neuroprotective effects accelerate and/or improve facial function recovery after facial nerve crush injury. STUDY DESIGN: Randomized animal study. SETTING: Tertiary care facility. METHODS: Eighty female Wistar-Hannover rats underwent head restraint implantation and daily conditioning. Animals then underwent unilateral crush injury to the main trunk of the facial nerve and were randomized to receive treatment with atorvastatin (n = 10), sildenafil (n = 10), darbepoetin (n = 20), or a corresponding control agent (n = 40). The return of whisking function was tracked throughout the recovery period. RESULTS: All rats initiated the return of whisking function from nerve crush by day 12. Darbepoetin-treated rats (n = 20) showed significantly improved whisking amplitude and velocity across the recovery period, with several days of significant pairwise differences vs comparable control rats (n = 16) across the first 2 weeks of whisking function return. In contrast, rats treated with sildenafil (n = 10) and atorvastatin (n = 10) did not show significant improvement in whisking function recovery after facial nerve crush compared to controls. By week 8, all darbepoetin-treated animals and comparable nerve crush control animals fully recovered whisking function and were statistically indistinguishable. CONCLUSION: Among the 3 potentially neuroprotective agents evaluated, only darbepoetin administration resulted in accelerated recovery of whisking parameters after facial nerve crush injury. Further efforts to define the mechanism of action and translate these findings to the use of darbepoetin in the care of patients with traumatic facial paralysis are needed.

Good correlation between original and modified House Brackmann facial grading systems.

OBJECTIVES/HYPOTHESIS: Subjective scales of facial function were plagued with reporting variations until the House-Brackmann scale was described in 1985. Despite its utility, weaknesses were identified, including noninclusion of synkinesis phenomena and insensitivity to segmental weakness. Therefore, the scale was recently revised to address these weaknesses. The objective of this investigation was to determine agreement between the original and the updated House-Brackmann scales. STUDY DESIGN: Prospective clinical trial. METHODS: Fifty consecutive new facial paralysis patients underwent standardized facial videography while performing facial movements. Video clips were scored by three independent facial nerve clinicians. The time it took to produce a score for each method was tracked. Interobserver correlations were calculated, and comparisons were made between scores by using the original and modified House-Brackmann scales. RESULTS: : Interobserver correlation was high for both House-Brackmann scales. Overall scores were in excellent agreement (difference of 0.1 ± 0.5, no statistical difference), although the modified scale took substantially longer to calculate (120 seconds ± 20 seconds vs. 30 seconds ± 10 seconds, P < .001). CONCLUSIONS: We found substantial grading correlation between the original and the newly modified House-Brackmann scales. Because of specific zonal and synkinesis scoring, the modified scale took longer to score.