Inhibition of TLR4 signaling protects mice from sensory and motor dysfunction in an animal model of autoimmune peripheral neuropathy.

BACKGROUND: While the etiology remains elusive, macrophages and T cells in peripheral nerves are considered as effector cells mediating autoimmune peripheral neuropathy (APN), such as Guillain-Barre syndrome. By recognizing both pathogen-associated molecular patterns (PAMPs) and damage-associated molecular patterns (DAMPs) signals, TLRs play a central role in the initiation of both innate and adaptive immune responses. In this study, we aimed to understand the involvement of TLR4 in the pathogenesis of APN and explore the potential of TLR4 as a drug target for therapeutic use. METHODS: APN was induced by a partial ligation on one of the sciatic nerves in B7.2 (L31) transgenic mice which possess a predisposed inflammatory background. APN pathology and neurological function were evaluated on the other non-injured sciatic nerve. RESULTS: TLR4 and its endogenous ligand HMGB1 were highly expressed in L31 mice, in circulating immune cells and in peripheral nerves. Enhanced TLR4 signaling was blocked with TAK 242, a selective TLR4 inhibitor, before and after disease onset. Intraperitoneal administration of TAK 242 not only inhibited monocyte, macrophage and CD8+ T cell activation, but also reduced the release of pro-inflammatory cytokines. TAK 242 protected mice from severe myelin and axonal loss, resulting in a remarkable improvement in mouse motor and sensory functions. TAK 242 was effective in alleviating the disease in both preventive and reversal paradigms. CONCLUSION: The study identified the critical contribution of TLR4-mediated macrophage activation in disease course and provided strong evidence to support TLR4 as a useful drug target for treating inflammatory autoimmune neuropathy.

Preservation of the Lesser Occipital Nerve Prevents Occipital Sensory Disturbance After Microvascular Decompression: Long-Term Results.

BACKGROUND: In microvascular decompression (MVD) surgery for hemifacial spasm (HFS), preservation of the lesser occipital nerve (LON) will prevent occipital sensory disturbance, a frequent complication of MVD, but the long-term outcome is unknown. This study was designed to evaluate the long-term efficacy of LON preservation. METHODS: This retrospective study included 257 patients with HFS who underwent suboccipital craniotomy with MVD. Among them, 175 were followed-up for more than 2 years. Occipital sensation was examined at 1, 12, and 24 months after MVD. The patients were classified into 3 groups based on their operative findings: LON preservation (group A; n = 112), LON not identified (group B; n = 117), and LON excision (group C; n = 28). The degree of sensory disturbance was evaluated using a visual analog scale (VAS) ranging from 1 (no sensation) to 10 (intact). RESULTS: The VAS score at 1 month was significantly better in group B (7.9 ± 0.2) than in groups A and C (7.3 ± 0.2 and 6.8 ± 0.4, respectively). At 24 months, the VAS scores were significantly higher in groups A and B (9.7 ± 0.1 and 9.7 ± 0.1) than in group C (8.8 ± 0.4), and occipital scalp sensation remained intact (VAS scores 9 and 10) in 91.9%, 92.9%, and 62.5% of the patients in groups A, B and C, respectively. CONCLUSIONS: Our long follow-up study has demonstrated that preservation of the LON during MVD prevents sensory disturbance of the occipital scalp. Efforts to preserve the LON appear to be worthwhile when the suboccipital approach is chosen.

Risk factors for and prevention of chronic pain and sensory disorders following inguinal hernia repair.

BACKGROUND: Inguinal hernia repair is one of the most common surgical procedures in man. Immediate postoperative pain is an important issue that can delay hospital discharge. Besides, the presence of chronic pain after herniorrhaphy, which can affect up to 50% of patients, is a growing concern. However information regarding the precise etiological factors of this chronic postoperative pain is lacking. One factor thought to contribute to post herniorrhaphy chronic pain is the surgical procedure for inguinal hernia repair used by the surgeon. MATERIALS AND METHOD: The study was conducted over a period of 5 years and included 1000 consecutive patients operated with inguinal hernia. Each patients completed a questionnaire about the presence or absence of pain or sensory disorders. After completed only 365 of patients remains in the study. From this patients, a total of 38 had different intensity of pain. From those, 13% were operated through an tissular procedure, whereas the laparoscopic procedure was responsible only for 7% of the patients with chronic postoperative pain. Most of the patients had mild or moderate pain and only one patient experienced severe pain. According to the type of procedure performed, in 25 patients were used the tissular procedure and only 12 patients with laparoscopic hernia repair had chronic pain. CONCLUSION: The etiology of chronic groin pain post hernia repair is related in part to nerve injury. This is supported by the high frequency of sensory symptoms and numbness in these patients. However other factors including the role of tissue injury and inflammatory postoperative changes need to be considered. KEY WORDS: Chronic postoperative pain, Inguinal hernia repair, Open surgery, Laparoscopic surgery.

Flunarizine for Headache Prophylaxis in Children With Sturge-Weber Syndrome.

BACKGROUND: Children with Sturge-Weber syndrome can experience severe headache with or without transient hemiparesis. Flunarizine, a calcium antagonist, has been used for migraine. The experience with flunarizine for headache in a cohort of children at a national center for Sturge-Weber syndrome is reviewed, reporting its efficacy and adverse effect in this population. METHODS: We collected data from health care professionals' documentation on headache (severity, frequency, duration) before and on flunarizine in 20 children with Sturge-Weber syndrome. Adverse effects reported during flunarizine treatment were collated. The Wilcoxon signed rank test was used to determine the significance of pre- versus post-treatment effect. RESULTS: Flunarizine was used for headache alone (13) or mixed migrainous episodes and vascular events (7). The median duration of treatment was 145 days (range 43 to 1864 days). Flunarizine reduced headache severity (z = -3.354, P = 0.001), monthly frequency (z = -2.585, P = 0.01), and duration (z = -2.549, P = 0.01). Flunarizine was discontinued owing to intolerable adverse effects in a minority (2). Sedation and weight gain were the most common side effects. There were no reports of behavior change or extrapyramidal features. CONCLUSIONS: The most effective management for headaches in patients with Sturge-Weber syndrome has not been established. This retrospective observational study found benefit of flunarizine prophylaxis on headache severity, frequency, and duration in children with Sturge-Weber syndrome without severe side effects. Flunarizine is not licensed for use in the United Kingdom, but these data support its off-license specialist use for headache prophylaxis in Sturge-Weber syndrome.

Enhanced Sensory-Cognitive Processing by Activation of Nicotinic Acetylcholine Receptors.

Activation of nicotinic acetylcholine receptors (nAChRs) enhances sensory-cognitive function in human subjects and animal models, yet the neural mechanisms are not fully understood. This review summarizes recent studies on nicotinic regulation of neural processing in the cerebral cortex that point to potential mechanisms underlying enhanced cognitive function. Studies from our laboratory focus on nicotinic regulation of auditory cortex and implications for auditory-cognitive processing, but relevant emerging insights from multiple brain regions are discussed. Although the major contributions of the predominant nAChRs containing α7 (homomeric receptors) or α4 and ß2 (heteromeric) subunits are well recognized, recent results point to additional, potentially critical contributions from α2 subunits that are relatively sparse in cortex. Ongoing studies aim to elucidate the specific contributions to cognitive and cortical function of diverse nAChRs. IMPLICATIONS: This review highlights the therapeutic potential of activating nAChRs in the cerebral cortex to enhance cognitive function. Future work also must determine the contributions of relatively rare but important nAChR subtypes, potentially to develop more selective treatments for cognitive deficits.

Sensation-Sparing Correction of Inverted Nipples Using the 'Drawbridge' Flap Approach.

INTRODUCTION: An inverted nipple can cause significant functional and psychologic disturbance to women. The holy grail of any surgical technique to correct this is to restore adequate nipple projection and at the same time, try to preserve lactation and nipple sensation. We describe our experience using an inferior dermal nipple-areolar interposition flap to correct the inverted nipple alongside with selective release of the lactiferous ducts of the nipple. MATERIALS AND METHODS: We have employed this technique successfully in 97 cases of inverted nipples in 60 patients with follow-up periods of up to 2 years. Twenty-three of them had unilateral inversion, and 37 of them had bilateral nipple inversion. RESULTS: The appearance of the nipple was good to excellent. Seventy to 80% of the initial postoperative nipple projection at the end of 1 year was maintained. Postoperative complications included stitch abscess in one patient (n = 1) and an epidermal cyst in another (n = 1). Nipple sensation was preserved in 100% of cases. There was no recurrence of inversion in any of the nipples. DISCUSSION: By identifying the root cause of inverted nipples in each individual case, and selectively targeting them, we minimize surgical morbidity with a simple technique that avoids any form of traction or compression of the nipple and minimizes the risk of altered nipple sensation. LEVEL OF EVIDENCE IV: This journal requires that authors assign a level of evidence to each article. For a full description of these evidence-based medicine ratings, please refer to the table of contents or the online instructions to authors www.springer.com/00266 .

Use of motor evoked potentials during lateral lumbar interbody fusion reduces postoperative deficits.

BACKGROUND CONTEXT: Intraoperative neurophysiological monitoring (IONM) has gained rather widespread acceptance as a method to mitigate risk to the lumbar plexus during lateral lumbar interbody fusion (LLIF) surgery. The most common approach to IONM involves using only electromyography (EMG) monitoring, and the rate of postoperative deficit remains unacceptably high. Other test modalities, such as transcranial electric motor-evoked potentials (tcMEPs) and somatosensory-evoked potentials, may be more suitable for monitoring neural integrity, but they have not been widely adopted during LLIF. Recent studies have begun to examine their utility in monitoring LLIF surgery with favorable results. PURPOSE: This study aimed to evaluate the efficacy of different IONM paradigms in the prevention of iatrogenic neurologic sequelae during LLIF and to specifically evaluate the utility of including tcMEPs in an IONM strategy for LLIF surgery. STUDY DESIGN/SETTING: A non-randomized, retrospective analysis of 479 LLIF procedures at a single institution over a 4-year period was conducted. During the study epoch, three different IONM strategies were used for LLIF procedures: (1) surgeon-directed T-EMG monitoring ("SD-EMG"), (2) neurophysiologist-controlled T-EMG monitoring ("NC-EMG"), and (3) neurophysiologist-controlled T-EMG monitoring supplemented with MEP monitoring ("NC-MEP"). PATIENT SAMPLE: The patient population comprised 254 men (53.5%) and 221 women (46.5%). Patient age ranged from a minimum of 21 years to a maximum of 89 years, with a mean of 56.6 years. OUTCOME MEASURES: Physician-documented physiological measures included manual muscle test grading of hip-flexion, hip-adduction, or knee-extension, as well as hypo- or hyperesthesia of the groin or anterolateral thigh on the surgical side. Self-reported measures included numbness or tingling in the groin or anterolateral thigh on the surgical side. METHODS: Patient progress notes were reviewed from the postoperative period up to 12 months after surgery. The rates of postoperative sensory-motor deficit consistent with lumbar plexopathy or peripheral nerve palsy on the surgical side were compared between the three cohorts. RESULTS: Using the dependent measure of neurologic deficit, whether motor or sensory, patients with NC-MEP monitoring had the lowest rate of immediate postoperative deficit (22.3%) compared with NC-EMG monitoring (37.1%) and SD-EMG monitoring (40.4%). This result extended to sensory deficits consistent with lumbar plexopathy (pure motor deficits being excluded); patients with NC-MEP monitoring had the lowest rate (20.5%) compared with NC-EMG monitoring (34.3%) and SD-EMG monitoring (36.9%). Additionally, evaluation of postoperative motor deficits consistent with peripheral nerve palsy (pure sensory deficits being excluded) revealed that the NC-MEP group had the lowest rate (5.7%) of motor deficit compared with the SD-EMG (17.0%) and NC-EMG (17.1%) cohorts. Finally, when assessing only those patients whose last follow-up was greater than or equal to 12 months (n=251), the rate of unresolved motor deficits was significantly lower in the NC-MEP group (0.9%) compared with NC-EMG (6.9%) and SD-EMG (11.0%). A comparison of the NC-MEP versus NC-EMG and SD-EMG groups, both independently and combined, was statistically significant (>95% confidence level) for all analyses. CONCLUSIONS: The results of the present study indicate that preservation of tcMEPs from the adductor longus, quadriceps, and tibialis anterior muscles are of paramount importance for limiting iatrogenic sensory and motor injuries during LLIF surgery. In this regard, the inclusion of tcMEPs serves to compliment EMG and allows for the periodic, functional assessment of at-risk nerves during these procedures. Thus, tcMEPs appear to be the most effective modality for the prevention of both transient and permanent neurologic injury during LLIF surgery. We propose that the standard paradigm for protecting the nervous system during LLIF be adapted to include tcMEPs.

Comparison of the Effects of Ultrasonic and Conventional Surgery on the Neurosensory Disturbance After Bilateral Sagittal Split Osteotomy.

PURPOSE: According to the literature, ultrasonic surgery reduces the incidence of neurosensory disturbance (NSD) of the inferior alveolar nerve (IFAN) after bilateral sagittal split osteotomy (BSSO). The purpose of this study was to evaluate the effects of ultrasonic surgery and the anatomic position of the IFAN canal on NSD after BSSO. PATIENTS AND METHODS: This retrospective cohort study included skeletal mandibular prognathism cases operated on with an ultrasonic bone scalpel or a reciprocating saw. The primary predictor variable was osteotomy technique (ultrasonic or conventional surgery). The primary outcome variable was NSD. Other variables included age, gender, operator, degree of setback, surgical duration, blood loss, and IFAN position. Comparisons of 2 variables were performed by use of the Student t test or Fisher exact test. A regression model was used to examine the relationship between the presence or absence of NSD and other variables. The level of significance was set at P < .05 for all statistical tests. RESULTS: The ultrasonic group was composed of 35 patients, whereas the conventional group was composed of 32. Three months after surgery, NSD was observed on 16 of 70 sides (22.9%) in the ultrasonic group and 28 of 64 sides (43.8%) in the conventional group; this difference was significant. Furthermore, recovery from NSD at 3 months after BSSO was significantly more common in the ultrasonic group than in the conventional group. In the ultrasonic group, even when the distance from the buccal aspect of the IFAN canal to the outer buccal cortical margin was shorter, NSD of the IFAN was less frequent. CONCLUSIONS: Ultrasonic surgery may be an effective technique to reduce the incidence of NSD after BSSO, and it contributed to recovery from NSD. The use of an ultrasonic device for BSSO is recommended when the distance from the buccal aspect of the IFAN canal to the outer buccal cortical margin is shorter on computed tomography.

Comparison of Sensory Changes Following Superomedial and Inferior Pedicle Breast Reduction.

BACKGROUND: More attention is focused on sensory outcomes following breast reduction operations. We conducted this prospective, non-randomized study to compare two commonly used breast reduction techniques, superomedial pedicle and inferior pedicle, regarding sensation of the nipple-areolar complex. METHODS: We prospectively assigned 60 patients with macromastia into the superomedial pedicle group (SMP group, n = 30) or the inferior pedicle (IP group, n = 30) group. Six patients who withdrew from the study and another six patients who did not attend return visits were excluded. Algometry was used to measure the sensation of breast skin, cardinal points of the areola and the nipple. Two-point discrimination was also measured on the areola. Measurements were performed before surgery, at 3 weeks, and 6 months postoperatively. RESULTS: There were 20 patients in the SMP group and 28 patients in the IP group. The mean ages of the patients were 43.2 ± 12.7 and 45.9 ± 10.8 years, respectively (p = 0.438). The mean BMI of the patients were 32.4 ± 6.7 and 30.4 ± 5.3 kg/m2, respectively (p = 0.257). The mean weights of resected tissues were 802.5 (280-2180) versus 773.7 (349.5-1425.0) g, respectively (p = 0.900). Although breast sensation did not change in the SMP group, sensation in the upper medial and lower lateral portions of breast skin was reduced in the IP group. Two-point discrimination test results did not change in either group. The amount of changes in algometry and two-point discrimination tests were similar in both groups. CONCLUSION: Both superomedial and inferior pedicle breast reduction techniques are safe and reliable in terms of sensory changes. LEVEL OF EVIDENCE III: This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to Table of Contents or the online Instructions to Authors www.springer.com/00266 .

Smokefree legislation effects on respiratory and sensory disorders: A systematic review and meta-analysis.

AIMS: The aim of this systematic review and meta-analysis is to synthesize the available evidence in scientific papers of smokefree legislation effects on respiratory diseases and sensory and respiratory symptoms (cough, phlegm, red eyes, runny nose) among all populations. MATERIALS AND METHODS: Systematic review and meta-analysis were carried out. A search between January 1995 and February 2015 was performed in PubMed, EMBASE, Cochrane Library, Scopus, Web of Science, and Google Scholar databases. Inclusion criteria were: 1) original scientific studies about smokefree legislation, 2) Data before and after legislation were collected, and 3) Impact on respiratory and sensory outcomes were assessed. Paired reviewers independently carried out the screening of titles and abstracts, data extraction from full-text articles, and methodological quality assessment. RESULTS: A total number of 1606 papers were identified. 50 papers were selected, 26 were related to symptoms (23 concerned workers). Most outcomes presented significant decreases in the percentage of people suffering from them, especially in locations with comprehensive measures and during the immediate post-ban period (within the first six months). Four (50%) of the papers concerning pulmonary function reported some significant improvement in expiratory parameters. Significant decreases were described in 13 of the 17 papers evaluating asthma hospital admissions, and there were fewer significant reductions in chronic obstructive pulmonary disease admissions (range 1-36%) than for asthma (5-31%). Six studies regarding different respiratory diseases showed discrepant results, and four papers about mortality reported significant declines in subgroups. Low bias risk was present in 23 (46%) of the studies. CONCLUSIONS: Smokefree legislation appears to improve respiratory and sensory symptoms at short term in workers (the overall effect being greater in comprehensive smokefree legislation in sensory symptoms) and, to a lesser degree, rates of hospitalization for asthma.

Chiari Malformation Type 1: A Systematic Review of Natural History and Conservative Management.

BACKGROUND: Chiari malformation type 1 (CM-1) is a variation of hindbrain development that can sometimes occur in asymptomatic individuals. Conventional treatment is surgical decompression, but little is known about the natural history of patients who do not undergo surgical management. This information is critical to determine how these patients should be managed. We conducted a systematic literature review to determine the natural history of CM-1, particularly in patients who did not undergo surgery and in asymptomatic individuals, to help patients and physicians determine when surgery is likely to be beneficial. METHODS: The literature search was performed following Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines using the electronic databases PubMed, Scopus, Cochrane Library, and Web of Science. Inclusion and exclusion criteria were predefined. RESULTS: In symptomatic patients who did not undergo surgery, headaches and nausea often improved, whereas ataxia and sensory disturbance tended not to improve spontaneously. Of patients, 27%-47% had an improvement in symptoms after 15 months, and 37%-40% with cough headache and 89% with nausea who were managed nonoperatively improved at follow-up. Most asymptomatic individuals with CM-1 remained asymptomatic (93.3%) even in the presence of syringomyelia. CONCLUSIONS: The natural history of mild symptomatic and asymptomatic CM-1 in adults is relatively benign and nonprogressive; the decision to perform surgical decompression should be based on severity and duration of a patient's symptoms at presentation. It is reasonable to observe a patient with mild or asymptomatic symptoms even in the presence of significant tonsillar descent or syringomyelia.

Microvascular Decompression for Trigeminal Neuralgia: Technical Refinement for Complication Avoidance.

BACKGROUND: Microvascular decompression (MVD) represents the most effective and safe surgical option for the treatment of trigeminal neuralgia since it was first popularized by Jannetta 50 years ago. Despite several advances, complications such as cerebellar and vascular injury, hearing loss, muscular atrophy, cerebrospinal fluid (CSF) leak, postoperative cutaneous pain, and sensory disturbances still occur and may negatively affect the outcome. We propose some technical nuances of the surgical procedure that were used in our recent series. METHODS: We used a novel hockey stick-shaped retromastoid skin incision, preserving the major nerves of the occipital and temporal areas. Microsurgical steps were performed without the use of retractors. CSF leakage was prevented with a watertight dural closure and multilayer osteodural reconstruction. RESULTS: The refined surgical steps were perfected in the last consecutive 15 cases of our series. In these cases we did not record any cutaneous pain, sensory disturbances, or CSF leakage. The average diameter of the craniectomy was 18 mm. No patient reported major complications related to the intradural microsurgical maneuvers. In all cases the neurovascular conflict was found and solved with a good outcome in terms of pain disappearance. CONCLUSIONS: Our minimally invasive approach was demonstrated to guarantee an optimal exposure of the cerebellopontine angle and minimize the rate of complications related to skin incision and muscular dissection, microsurgical steps, and closure.

Valproic acid ameliorates olfactory dysfunction in APP/PS1 transgenic mice of Alzheimer's disease: Ameliorations from the olfactory epithelium to the olfactory bulb.

Olfactory dysfunction is a common and early symptom of many neurodegenerative diseases, particularly of Alzheimer's disease (AD) and mild cognitive impairment, pointing to the progression to dementia. Recent studies have revealed that valproic acid (VPA) has neuroprotective effects in rodent models of AD. In this study, we investigated the effects of VPA on olfactory dysfunction of APP/PS1 double transgenic mouse models of AD. After continuous treatment with a 100mg/kg daily dose of VPA for 3 months, APP/PS1 mice showed improved olfactory performances. In agreement with the behavioral findings, VPA treatment reduced amyloid ß (Aß) burden in the olfactory epithelium (OE) of transgenic mice. And, VPA increased epithelial thickness of the olfactory mucosa through decreased cell apoptosis and increased cell proliferation. In the olfactory bulb (OB), VPA administration also reduced senile plaques and levels of soluble and insoluble Aß42 peptides. Besides, VPA promoted the increase of mitral cells and decrease of neurofilament immunostaining. In hence, VPA treatment completely improved the olfactory performances and prevented degenerative changes of the OE and OB. Our study raises the possibility of AD diagnosis by OE biopsy. Moreover, VPA may provide a novel therapeutic strategy for the treatment of olfactory dysfunction in AD patients.

Clinical significance of lesser occipital nerve preservation during micro-vascular decompression for hemi-facial spasm.

BACKGROUND: Micro-vascular decompression (MVD) is a useful surgical technique in treating hemi-facial spasm (HFS). However, sensory disturbance and headache are the common postoperative complications. AIMS: This study seeked to estimate whether lesser occipital nerve (LON) preservation was conducive to reducing the incidence of adverse events. METHODS: We retrospectively compared the operation time and postoperative complications between 28 HFS patients who underwent MVD with LON preservation from January 2011 to December 2012 (LON preservation group) and 12 HFS patients who underwent MVD without preserving LON in 2010 (control group). RESULTS: Compared with the control group, patients in the LON preservation group showed increased operation time but reduced incidences of sensory disturbances around occipitalis (P = 0.017) and posterior auricular (P = 0.002). However, there were no significant differences in other postoperative complications such as headache (P = 0.414), incision infection (P = 0.527) or cerebrospinal fluid leakage (P = 0.527). CONCLUSIONS: For HFS patients who attempted to receive MVD, LON preservation could reduce the incidence of sensory disturbance around the operative region, despite causing extend operation time.

[The study of preserving the great auricular nerve in the parotidectomy].

OBJECTIVE: To assess the effect for local sensory to preserve great auricular nerve in the parotidectomy. METHOD: It was a prospective study. Eighy-one patients who underwent parotidectomy were randomly divided into 2 groups, preserving the great auricular nerve group and no preserving the great auricular nerve group. They were tested with the subjective and objective sensory function testing in 3, 6, 9, 12 months after operation. We assessed the result. RESULT: In the subjective sensory function testing, the result of the preserving the great auricular nerve group was better than no preserving the great auricular nerve group. In the objective sensory function testing, the result of the preserving the great auricular nerve group was obviously better than no preserving the great auricular nerve group. There was significant difference between the 2 groups (P<0.05). CONCLUSION: It was effective for recovering the sensory function that we preserved the great auricular nerve in the parotidectomy.

Great auricular nerve preservation in parotid surgery: rationale and long-term results insights.

Great auricular nerve (GAN) is frequently sacrificed during parotid surgery. GAN preservation during parotidectomy is advised to avoid complications such as sensitive disorders, but debate still exists. In this study, our experience is reported on the matter. From a cohort of 173 parotidectomies carried out in the period 2005-2010, we studied 60 patients: 20 patients in which we preserved only the posterior branch of GAN (group A), 20 patients in which we preserved also the lobular branch (group B) and 20 patients in which the main trunk of GAN was sectioned (group C); we evaluated tactile sensitivity in all the skin supplied by GAN at 1 week, 1 month, 6 months and 1 year after surgery. Group B is the best in terms of loss and recovery of sensitivity after 1-year post-surgery, followed closely by group A, on the contrary group C confirmed to be the worst. Results suggest that saving as many branches of the GAN as possible during parotid surgery could be useful for reducing hypo-dysesthesia. Preserving posterior and lobular branches of the GAN, when possible, improves the sensitivity of the preauricular area with better quality of life for the patient.

Regression analysis of correlated ordinal data using orthogonalized residuals.

Semi-parametric regression models for the joint estimation of marginal mean and within-cluster pairwise association parameters are used in a variety of settings for population-averaged modeling of multivariate categorical outcomes. Recently, a formulation of alternating logistic regressions based on orthogonalized, marginal residuals has been introduced for correlated binary data. Unlike the original procedure based on conditional residuals, its covariance estimator is invariant to the ordering of observations within clusters. In this article, the orthogonalized residuals method is extended to model correlated ordinal data with a global odds ratio, and shown in a simulation study to be more efficient and less biased with regards to estimating within-cluster association parameters than an existing extension to ordinal data of alternating logistic regressions based on conditional residuals. Orthogonalized residuals are used to estimate a model for three correlated ordinal outcomes measured repeatedly in a longitudinal clinical trial of an intervention to improve recovery of patients' perception of altered sensation following jaw surgery.

Atorvastatin protects GABAergic and dopaminergic neurons in the nigrostriatal system in an experimental rat model of transient focal cerebral ischemia / La atorvastatina protege las neuronas gabérgicas y dopaminérgicas del sistema nigroestriatal en un modelo experimental de isquemia cerebral focal transitoria en ratas

Introduction: Cerebral ischemia is the third leading cause of death and the primary cause of permanent disability worldwide. Atorvastatin is a promising drug with neuroprotective effects that may be useful for the treatment of stroke. However, the effects of atorvastatin on specific neuronal populations within the nigrostriatal system following cerebral ischemia are unknown. Objective: To evaluate the effects of atorvastatin on dopaminergic and GABAergic neuronal populations in exofocal brain regions in a model of transient occlusion of the middle cerebral artery. Materials and methods: Twenty-eight male eight-week-old Wistar rats were used in this study. Both sham and ischemic rats were treated with atorvastatin (10 mg/kg) or carboxymethylcellulose (placebo) by gavage at 6, 24, 48 and 72 hours post-reperfusion. We analyzed the immunoreactivity of glutamic acid decarboxylase and tyrosine hydroxylase in the globus pallidus, caudate putamen and substantia nigra. Results: We observed neurological damage and cell loss in the caudate putamen following ischemia. We also found an increase in tyrosine hydroxylase immunoreactivity in the medial globus pallidus and substantia nigra reticulata, as well as a decrease in glutamic acid decarboxylase immunoreactivity in the lateral globus pallidus in ischemic animals treated with a placebo. However, atorvastatin treatment was able to reverse these effects, significantly decreasing tyrosine hydroxylase levels in the medial globus pallidus and substantia nigra reticulata and significantly increasing glutamic acid decarboxylase levels in the lateral globus pallidus. Conclusion: Our data suggest that post-ischemia treatment with atorvastatin can have neuro-protective effects in exofocal regions far from the ischemic core by modulating the GABAergic and dopaminergic neuronal populations in the nigrostriatal system, which could be useful for preventing neurological disorders.

Introducción. La isquemia cerebral es la tercera causa de muerte y la primera de discapacidad permanente en el mundo. La atorvastatina es un fármaco neuroprotector prometedor para el tratamiento de la apoplejía; sin embargo, su acción sobre las poblaciones neuronales del sistema nigroestriatal después de la isquemia aún se desconoce. Objetivo. Evaluar el efecto de la atorvastatina sobre poblaciones gabérgicas y dopaminérgicas en regiones exofocales en un modelo de oclusión transitoria de la arteria cerebral media. Materiales y métodos. Se utilizaron 28 ratas Wistar macho de ocho semanas de edad. Los ejemplares con isquemia simulada y los ejemplares sometidos a isquemia fueron tratados con atorvastatina (10 mg/kg) y carboximetilcelulosa (placebo) administrados por medio de sonda a las 6, 24, 48 y 72 horas después de la reperfusión. Se analizó la inmunorreacción de la descarboxilasa del ácido glutámico y de la tirosina hidroxilasa en el globo pálido, el putamen caudado y la sustancia negra. Resultados. Los datos confirmaron el daño neurológico y la pérdida celular en el putamen caudado. Se incrementó la inmunorreacción de la tirosina hidroxilasa en el globo pálido medial y la sustancia negra pars reticulata , disminuyendo la inmunorreacción de la descarboxilasa del ácido glutámico en el globo pálido lateral de los animales isquémicos tratados con placebo; sin embargo, el tratamiento con atorvastatina pudo revertirla, lo que logró una disminución significativa de la tirosina hidroxilasa en el globo pálido medial y la sustancia negra pars reticulata y aumentando los niveles de descarboxilasa del ácido glutámico en el globo pálido lateral. Conclusión. Nuestros datos sugieren que la atorvastatina en el tratamiento posterior a la isquemia ejerce neuroprotección en las zonas exofocales, modulando las poblaciones neuronales gabérgicas y dopaminérgicas del sistema nigroestriatal, lo que podría prevenir trastornos neurológicos.

Preservation of greater auricular nerve during parotidectomy: sensation, quality of life, and morbidity issues. A systematic review.

BACKGROUND: Our objectives were to assess the evidence of preservation of the greater auricular nerve in parotidectomy with regard to morbidity and quality of life. METHODS: This was a systematic review. Inclusion criteria were: English literature, prospective and retrospective studies. Exclusion criteria were: single case reports, "teaching" reviews. Outcome measures were: tactile sensation, pain, thermal sensitivity, and quality of life. RESULTS: Although quality of life does not seem to be adversely affected when the greater auricular nerve is sacrificed, preservation of the posterior branch was recommended in 8 studies. When preserving the nerve, the incremental operative time increase is no more than 10 to 5 minutes after a rapid learning curve. CONCLUSIONS: There is level Ib evidence that preservation of the greater auricular nerve minimizes the postoperative sensory disturbance and should be considered whenever tumor clearance is not compromised. There is no evidence that overall quality of life is affected when the greater auricular nerve is sacrificed.