Metodologia para análise da confiabilidade estrutural de escavações em rocha.

A methodology for rock-excavation structural-reliability analysis that uses Distinct Element Method numerical models is presented. The methodology solves the problem of the conventional numerical models that supply only punctual results and use fixed input parameters, without considering its statistical errors. The analysis of rock-excavation stability must consider uncertainties from geological variability, from uncertainty in the choice of mechanical behaviour hypothesis, and from uncertainties in parameters adopted in numerical model construction. These uncertainties can be analyzed in simple deterministic models, but a new methodology was developed for numerical models with results of several natures. The methodology is based on Monte Carlo simulations and uses principles of Paraconsistent Logic. It will be presented in the analysis of a final slope of a large-dimensioned surface mine.

Análise econômica comparativa de empresas de água mineral quanto ao porte

This work makes a comparative economic analysis of a small-, medium- and large-sized mineral water company, the three of which are localized in the State of Sao Paulo. All have the same lines of production such as glasses, bottles and big bottles. The analysis involves the cash flow comparison of the three companies.

Patterns of brain asymmetry in the perception of positive and negative facial expressions

The divided visual field technique was used to investigate the pattern of brain asymmetry in the perception of positive/approach and negative/withdrawal facial expressions. A total of 80 undergraduate students (65 female, 15 male) were distributed in five experimental groups in order to investigate separately the perception of expressions of happiness, surprise, fear, sadness, and the neutral face. In each trial a target and a distractor expression were presented simultaneously in a computer screen for 150 ms and participants had to determine the side (left or right) on which the target expression was presented. Results indicated that expressions of happiness and fear were identified faster when presented in the left visual field, suggesting an advantage of the right hemisphere in the perception of these expressions. Fewer judgement errors and faster reaction times were also observed for the matching condition in which emotional faces were presented in the left visual field and neutral faces in the right visual field. Other results indicated that positive expressions (happiness and surprise) were perceived faster and more accurately than negative ones (sadness and fear). Main results tend to support the right hemisphere hypothesis, which predicts a better performance of the right hemisphere to perceive emotions, as opposed to the approach-withdrawal hypothesis.

Hemihypoglossal-facial neurorrhaphy after mastoid dissection of the facial nerve: Results in 24 patients and comparison with the classic technique

OBJECTIVE: Hypoglossal-facial neurorrhaphy has been widely used for reanimation of paralyzed facial muscles after irreversible proximal injury of the facial nerve. However, complete section of the hypoglossal nerve occasionally results in hemiglossal dysfunction and interferes with swallowing and speech. To reduce this morbidity, a modified technique with partial section of the hypoglossal nerve after mastoid dissection of the facial nerve (HFM) has been used. We report our experience with the HFM technique, retrospectively comparing the outcome with results of the classic hypoglossal-facial neurorrhaphy. METHODS: A retrospective review was performed in 36 patients who underwent hypoglossal-facial neurorrhaphy with the classic (n = 12) or variant technique (n = 24) between 2000 and 2006. Facial Outcome was evaluated with the House-Brackmann grading system, and tongue function was evaluated with a new scale proposed to quantify Postoperative tongue alteration. The results were compared, and age and time between nerve injury and surgery were correlated with the outcome. RESULTS: There was no significant difference between the two techniques concerning facial reanimation. A worse outcome of tongue function, however, was associated with the classic technique (Mann-Whitney U test; P < 0.05). When HFM was used, significant correlations defined by the Spearman test were identified between preoperative delay (p = 0.59; P = 0.002) or age (p = 0.42; P = 0.031) and results of facial reanimation evaluated with the House-Brackmann grading system. CONCLUSION: HFM is as effective as classic hypoglossal-facial neurorrhaphy for facial reanimation, and it has a much lower morbidity related to tongue function. Better results are obtained in younger patients and with a shorter interval between facial nerve injury and surgery.

Is facial pattern a predisposing factor for otitis media with effusion in children?

Abnormalities in craniofacial morphology are associated with Eustachian tube dysfunction and otitis media with effusion (OME). Aim: to evaluate the relationship between facial pattern and craniofacial growth direction, and OME in children with enlarged tonsils and adenoids (ETA). Methods: Clinical prospective survey in 79 children (41 male and 38 female), ranging from 4 to 10 years of age, with tonsil and adenoid enlargement (Brodsky`s grades III and IV). Forty children presented with OME (study group) and 39 did not (control group). Cephalometric analysis was used to determine the facial pattern. Results: There was no correlation observed between facial pattern and OME (c 2 = 0.25 p = 0.88). Facial Axis was larger in the OME group (F(1.75) = 3.68 p = 0.05) and the Lower Anterior Facial height was smaller (F(1. 75) = 3.99 p = 0.05) in children with otitis media with effusion. Conclusions: There was no correlation between OME and facial pattern in children with ETA although a more horizontal facial growth direction, and a smaller lower anterior facial height was observed consistently among subjects in this group. This suggests that abnormal positioning of the eustachian tube influences the development of OME in children with ETA.

Facial Palsy After Blunt Trauma and Without Facial Bone Fracture

A 14-year-old patient had a low-energy facial blunt trauma that evolved to right facial paralysis caused by parotid hematoma with parotid salivary gland lesion. Computed tomography and angiography demonstrated intraparotid collection without pseudoaneurysm and without radiologic signs of fracture in the face. The patient was treated with serial punctures for hematoma deflation, resolving with regression and complete remission of facial paralysis, with no late sequela. The authors discuss the relationship between facial nerve traumatic injuries associated or not with the presence of facial fractures, emphasizing the importance of early recognition and appropriate treatment of such cases.

Muscle Transplants for Facial Reanimation Rationale and Results of Insertion Technique Using the Palmaris Longus Tendon

Thirty-one patients with unilateral long-standing facial palsy underwent I-stage reanimation with free gracilis muscle transplant innervated by the masseteric branch of the trigeminal nerve. They were divided into 2 nonrandomized groups according to insertion technique: group 1 (9 patients), interrupted suture between the free flap and the orbicularis oris of the upper and lower lip on the paralyzed side; group It (22 patients), palmaris longus tendon graft placed between the gracilis free flap and the orbicularis oris of the upper and lower lip on the nonparalyzed side. Qualitative evaluation of the smile demonstrated better results in patients from group II. Comparing the position Of the Cupid`s bow at rest, pre- and postoperatively in each patient, we observed significant improvement of facial symmetry in both groups. During smile, however, there was a significantly higher rate of centralization of the Cupid`s bow in patients submitted to reanimation with the use of the palmaris longus tendon (group II).

Botulinum Toxin Injection in Long-Standing Facial Paralysis Patients: Improvement of Facial Symmetry Observed up to 6 Months

Despite modern reanimation surgical techniques, facial paralysis presents with functional and aesthetic deficits. We evaluated facial symmetry after treating with botulinum toxin the healthy side of the face of 25 patients with long-standing facial paralysis who had previously been treated by surgical methods, with 6 months follow-up. Evaluation consisted of a clinical score, the two subscales of the Facial Disability Index, and surface electromyography. The mean botulinum toxin dose was 38 +/- A 5 U (range = 15-69 U). The clinical score showed significant reduction of asymmetry of 48.4% at 1 month and 16.8% after 6 months. The initial result was a consequence of reduced motion on the treated side combined with better motion on the paralyzed side. At 6 months, the treated side returned to basal scores. The residual effect seen in symmetry was due to an increase (18%) of motion in the paralyzed side. There was a significant decrease in the action potential of muscles on the nonparalyzed side 1 month post injection but completely reverted after 6 months. The Physical Function Index increased, but not significantly. The Social/Well-Being Function Index showed a significant increase at 6 months compared to pretreatment. The proposed treatment improved facial symmetry for up to 6 months. Even after the end of the clinical effect of the drug, the paralyzed side`s clinical score was 18% higher than pretreatment, with an increased quality of life.

The Tessier Number 5 Facial Cleft: Surgical Strategies and Outcomes in Six Patients

The Tessier no. 5 facial cleft is an extremely rare congenital malformation. Only 26 cases have been described In the English-language literature. The cleft begins In the upper lip just medial to the oral commissure, extending across the cheek as a groove ending at the junction of the middle and lateral thirds of the lower eyelid. The bone Involvement usually Includes an alveolar cleft in the premolar region, extends across the maxilla lateral to the Infraorbital nerve, up to the infraorbital rim and orbital floor. The goals of the surgical procedure Include reconstructing the lower eyelid, repositioning the lateral canthus, closure of the labiomaxillary cleft, and restoration of the skeletal continuity (including the orbital floor defect) with bone grafts. We present six patients with the Tessier no. 5 facial cleft who have been treated in our combined centers and discuss the surgical options and difficulties faced in the reconstruction of this rare and challenging craniofacial malformation. To date, we have treated six patients (two with bilateral and four with unilateral clefts). Three of the patients with unilateral clefting had an associated no. 4 cleft and one patient with a bilateral cleft had an associated no. 3 cleft. This paper represents the largest series to date documenting surgery for patients with the Tessier no. 5 facial cleft.

Tessier No. 4 Facial Cleft: Evolution of Surgical Treatment in a Large Series of Patients

Background: Tessier no. 4 facial cleft is a rare, complex, and challenging craniofacial malformation. The present article aims to describe different clinical features evidenced in 21 cases of this malformation, discussing a 20-year experience with and evolution of its surgical treatment. Methods: Some demographic data, clinical features, and reconstructive results were evaluated retrospectively. These patients have been evaluated and treated in three specialized Brazilian craniofacial centers. Nineteen were already operated on, with a mean follow-up of 3.5 years (range, 1 to 20 years). Results: Sex distribution showed a male prevalence (2: 1). The average age of initial treatment was 5.4 years. Four cases were affected on the right side of the face, seven on the left, and 10 bilaterally. Six patients had other rare associated facial clefts, including nos. 5 (three patients), 7, 9, and 10. Cleft upper lip was evidenced in all patients, and maxillary hypoplasia was present in five and maxilla cleft in eight. Lower eyelid coloboma was seen in almost every case (19 patients); 10 of these had medial canthus dystopia. Four patients had amniotic bands in the limbs. Surgical repair was individualized to each patient. Surgical experience gained with these patients allowed the authors to develop some technical modifications, which have improved aesthetic results, camouflaging scars into natural folds and anatomical units, without compromising functional outcomes. Conclusions: The great majority of Tessier no. 4 facial clefts can be appropriately treated using local flaps. Classic techniques are extremely useful, but long-term results could be improved if the technical modifications described were adopted. (Plast. Reconstr. Surg. 122: 1505, 2008.)

Partial lesions of the intratemporal segment of the facial nerve: Graft versus partial reconstruction

Objectives: In cases of partial lesions of the intratemporal segment of the facial nerve, should the surgeon perform an intraoperative partial reconstruction, or partially remove the injured segment and place a graft? We present results from partial lesion reconstruction on the intratemporal segment of the facial nerve. Methods: A retrospective study on 42 patients who presented partial lesions on the intratemporal segment of the facial nerve was performed between 1988 and 2005. The patients were divided into 3 groups based on the procedure used: interposition of the partial graft on the injured area of the nerve (group 1; 12 patients); keeping the preserved part and performing tubulization (group 2; 8 patients); and dividing the parts of the injured nerve (proximal and distal) and placing a total graft of the sural nerve (group 3; 22 patients). Results: Fracture of the temporal bone was the most frequent cause of the lesion in all groups, followed by iatrogenic causes (p < 0.005). Those who obtained results lower than or equal to III on the House-Brackmann scale were 1 (8.3%) of the patients in group 1, none (0.0%) of the patients in group 2, and 15 (68.2%) of the patients in group 3 (p < 0.001). Conclusions: The best surgical technique for therapy of a partial lesion of the facial nerve is still questionable. Among these 42 patients, the best results were those from the total graft of the facial nerve.

Malformations of Cortical Development in Patients With Mid line Facial Defects and Ocular Hypertelorism

Objectives: We studied the neuroimaging and neurophysiological aspects of 17 patients with midline facial defects with ocular hypertelorism (MFDH). Methods: The investigation protocol included a previous semistructured questionnaire about family history; gestational, neonatal, and postnatal development; and dysmorphologic and neurologic evaluation. Recognized monogenic disorders and individuals with other well-known conditions were excluded. All patients had high resolution magnetic resonance imaging (MRI) with multiplanar reconstruction (MPR) and routine electroencephalograms (EEGs). Results: We detected abnormalities in five patients whose MRIs had been previously reported as normal. MRI showed central nervous system (CNS) structural abnormalities in all patients, which included commissural alterations in 16/17 (94%), malformations of cortical development in 10/17 (58%), disturbances of neural tube closure in 7/17(42%), and posterior fossa anomalies in 6/17 (35%). Some patients had more than one type of malformation occurring at different stages of the embryonary process. EEGs showed epileptiform activity in 4/17 (24%) and background abnormalities in 5/17 (29%) of patients. Conclusion: This study clearly demonstrated the presence of structural and functional neurologic alterations related to MFDH. Therefore, the CNS anomalies cannot be considered incidental findings but an intrinsic part of this condition, which could be related to environmental effects and/or genetic mutations. These findings would provide a basis for future investigations on MFDH and should also be considered when planning rehabilitation.

Transcranial Electrocortical Stimulation to Monitor the Facial Nerve Motor Function During Cerebellopontine Angle Surgery

OBJECTIVE: This study was conducted to investigate the success rate of using the facial motor evoked potential (FMEP) of orbicularis oculi and oris muscles for facial nerve function monitoring with use of a stepwise protocol, and its usefulness in predicting facial nerve outcome during cerebellopontine angle (CPA) surgeries. METHODS: FMEPs were recorded intraoperatively from 60 patients undergoing CPA surgeries. Transcranial electrocortical stimulation (TES) was performed using corkscrew electrodes positioned at hemispheric montage (C3/C4 and CZ). The contralateral abductor pollicis brevis muscle was used as the control response. Stimulation was always applied contralaterally to the affected side using 1, 3, or 5 rectangular pulses ranging from 200 to 600 V with 50 mu s of pulse duration and an interstimulus interval of 2 ms. Facial potentials were recorded from needles placed in the orbicularis oculi and oris muscles. RESULTS: FMEP from the orbicularis oris and oculi muscles could be reliably monitored in 86.7% and 85% of the patients, respectively. The immediate postoperative facial function correlated significantly with the FMEP ratio in the orbicularis oculi muscle at 80% amplitude ratio (P =.037) and orbicularis oris muscle at 35% ratio (P =.000). FMEP loss was always related to postoperative facial paresis, although in different degrees. CONCLUSION: FMEPs can be obtained reliably by using TES with 3 to 5 train pulses. Stable intraoperative FMEPs can predict a good postoperative outcome of facial function. However, further refinements of this technique are necessary to minimize artifacts and to make this method more reliable.

Elevated Amygdala Activity to Sad Facial Expressions: A State Marker of Bipolar but Not Unipolar Depression

Background: Difficulties in emotion processing and poor social function are common to bipolar disorder (BD) and major depressive disorder (MDD) depression, resulting in many BID depressed individuals being misdiagnosed with MDD. The amygdala is a key region implicated in processing emotionally salient stimuli, including emotional facial expressions. It is unclear, however, whether abnormal amygdala activity during positive and negative emotion processing represents a persistent marker of BD regardless of illness phase or a state marker of depression common or specific to BID and MDD depression. Methods: Sixty adults were recruited: 15 depressed with BID type 1 (BDd), 15 depressed with recurrent MDD, 15 with BID in remission (BDr), diagnosed with DSM-IV and Structured Clinical Interview for DSM-IV Research Version criteria; and 15 healthy control subjects (HC). Groups were age- and gender ratio-matched; patient groups were matched for age of illness onset and illness duration; depressed groups were matched for depression severity. The BDd were taking more psychotropic medication than other patient groups. All individuals participated in three separate 3T neuroimaging event-related experiments, where they viewed mild and intense emotional and neutral faces of fear, happiness, or sadness from a standardized series. Results: The BDd-relative to HC, BDr, and MDD-showed elevated left amygdala activity to mild and neutral facial expressions in the sad (p < .009) but not other emotion experiments that was not associated with medication. There were no other significant between-group differences in amygdala activity. Conclusions: Abnormally elevated left amygdala activity to mild sad and neutral faces might be a depression-specific marker in BID but not MDD, suggesting different pathophysiologic processes for BD versus MDD depression.

Quantitative parameters of facial motor evoked potential during vestibular schwannoma surgery predict postoperative facial nerve function

Background Facial motor evoked potential (FMEP) amplitude ratio reduction at the end of the surgery has been identified as a good predictor for postoperative facial nerve outcome. We sought to investigate variations in FMEP amplitude and waveform morphology during vestibular schwannoma (VS) resection and to correlate these measures with postoperative facial function immediately after surgery and at the last follow-up. Methods Intraoperative orbicularis oculi and oris muscles FMEP data from 35 patients undergoing surgery for VS resection were collected, then analysed by surgical stage: initial, dural opening, tumour dissection (TuDis), tumour resection (TuRes) and final. Findings Immediately after surgery, postoperative facial function correlated significantly with the FMEP amplitude ratio during TuDis, TuRes and final stages in both the orbicularis oculi (p = 0.003, 0.055 and 0.028, respectively) and oris muscles (p = 0.002, 0.104 and 0.014, respectively). At the last follow-up, however, facial function correlated significantly with the FMEP amplitude ratio only during the TuDis (p = 0.005) and final (p = 0.102) stages for the orbicularis oris muscle. At both time points, postoperative facial paresis correlated significantly with FMEP waveform deterioration in orbicularis oculi during the final stage (immediate, p = 0.023; follow-up, p = 0.116) and in orbicularis oris during the TuDis, TuRes and final stages (immediate, p = 0.071, 0.000 and 0.001, respectively; follow-up, p = 0.015, 0.001 and 0.01, respectively). Conclusions FMEP amplitude ratio and waveform morphology during VS resection seem to represent independent quantitative parameters that can be used to predict postoperative facial function. Event-to-baseline FMEP monitoring is quite useful to dictate when intraoperative changes in surgical strategy are warranted to reduce the chances of facial nerve injury.