Number Of Maneuvers Research Articles

Benefit of educational feedback for the use of positive expiratory pressure device.

BACKGROUND: Positive expiratory pressure (PEP) is regularly used as a self-administered airway clearance technique. OBJECTIVE: The aim of this study was to evaluate the need to teach the correct use of the PEP device and to measure the progress of the success rate of the maneuver after training. METHOD: A PEP system (PariPEP-S Sytem) was used to generate PEP in 30 healthy volunteers. They were instructed by a qualified physical therapist to breathe correctly through the PEP device. Then they were evaluated during a set of ten expirations. Two other evaluations were performed at day 2 and day 8 (before and after feedback). The mean PEP and the success rate were calculated for each set of expirations. The number of maneuvers needed to obtain a correct use was calculated on the first session. RESULTS: An optimal PEP was reached after 7.5 SD 2.7 attempts by all subjects. Success rates and mean pressures were similar between the different sets of expirations (p=0.720 and p=0.326, respectively). Pressure variability was around 10%. After one week, 30% of subjects generated more than two non-optimal pressures in the set of ten expirations. No difference in success rate was observed depending on the evaluations. CONCLUSION: This study demonstrates that good initial training on the use of the PEP device and regular follow-up are required for the subject to reach optimal expiratory pressure.

Planning safe navigation routes through mined waters

In this paper we investigate the problem of finding a safe transit of a ship through areas threatened by sea mines. The aim is to provide decision-making support by a tool that can be integrated into a naval command and control system. We present a route finding algorithm which avoids regions of risk higher than a given threshold. The algorithm takes into account the technical and operational restrictions of the ship’s movement. It allows to minimize the route length, the traveling time, the number of maneuvers, or other objectives.The basic idea is to embed a network in the operational area and compute a least-cost path. Instead of using a regular grid graph which strongly restricts the types of maneuvers and necessitates a path smoothing after optimization, we design a network which is especially tailored to the maneuverability of the vessel. Each path in this network represents a continuous-curvature track based on combinations of clothoids and straight line segments. The approach allows a large variety of maneuvers, hence high-quality solutions are achievable provided a sufficiently dense network.

Spirometric standards and patient characteristics: an exploratory study of factors affecting fulfillment in routine clinical practice.

Spirometry is an apparently simple test, yet the recommended criteria for acceptability and reproducibility can be difficult to fulfill. This study aimed (1) to prospectively assess the number of tests that meet the American Thoracic Society/European Respiratory Society (ATS/ERS) 2005 acceptability and repeatability criteria in the routine practice of an experienced technician at a referral hospital's lung function laboratory, (2) to identify the most common errors, and (3) to explore patient characteristics possibly associated with failure to meet standards. We prospectively evaluated 257 consecutive spirometries supervised by the same technician, who gave priority to achieving a minimum of 3 correct maneuvers within a maximum of 8 attempts. We recorded FVC, FEV1, expiratory time (TE), back-extrapolated volume (VE), end-of-test volume (VEOT), number of maneuvers with and without errors, and errors (VE > 0.15 L or 5% of FVC, TE < 6 s, and VEOT ≥ 0.025 L for ≥ 1 s). Two-hundred and fifteen spirometries (83.7%, 95% CI 78.6-87.7%) met the ATS/ERS 2005 criteria. Acceptability criteria were met in 73.9% (95% CI 71.2-76.3%) of the maneuvers and repeatability criteria in 90.7% (95% CI 86.5-93.6%). A mean ± SD of 3.3 ± 1.4 per subject was acceptable, and a mean ± SD of 4.5 ± 1.9 was obtained. TE and VEOT errors were the most common. Nearly 15% of the subjects failed to fulfill all the ATS/ERS 2005 criteria for spirometry performed even though they were coached by a qualified and regularly trained technician in a hospital lung function laboratory. The fact that the ATS/ERS 2005 criteria cannot be met by all patients in optimal technical conditions should be further considered and explored.

Control of orientation for spacecraft formations in the vicinity of the Sun-Earth L2 libration point

Formation flying in the vicinity of the libration point is an important concept for space exploration and demands reliable and accurate techniques for the control of a spacecraft. On the basis of previous works, this paper addresses the problem of relative orientation control of spacecraft formation flying utilizing the framework of the circular restricted three-body problem (CR3BP) with the Sun and Earth as the primary gravitational bodies. Two specific tasks are accomplished in this study. First, the tangent targeting method (TTM), an efficient two-level differential correction algorithm, is exploited to control the Chief/Deputy architecture to maintain a prespecified orientation. The time spent within the orientation error corridor between successive maneuvers is maximized while the relative separation between the vehicles is held constant at each target point. The second task is to further optimize the maneuver intervals by dropping the constraint imposed on the relative vehicle separation. Numerical investigation indicates that the number of maneuvers can be significantly reduced and the length of time between successive maneuvers can be greatly increased by utilizing the TTM.

Peri-interventional Subarachnoid Hemorrhage During Mechanical Thrombectomy with stent retrievers in Acute Stroke: A Retrospective Case-Control Study

Mechanical thrombectomy with stent retrievers in acute stroke has emerged as a promising new technique with the highest recanalization rate of the therapeutic procedures available so far. However, endovascular treatment is also associated with the risk of specific complications. One of those is the occurrence of peri-interventional subarachnoid hemorrhage (SAH), which has been reported in 5-16 % of the cases. Interestingly, this rate is higher than that of angiographically detectable perforations (0-3 %), leaving the majority of peri-interventional SAH to be due to angiographically occult perforations. Little is known about the influence of this finding on clinical outcome. The purpose of this study was to investigate the clinical relevance of SAH due to occult perforations during thrombectomy with stent retrievers. Postinterventional computed tomography (CT) scans of 217 consecutive patients with acute occlusions of intracerebral arteries who were treated with stent retrievers in our department between October 2009 and October 2012 were retrospectively analyzed. SAH was found on postinterventional CT scans in 5.5 % of the cases. Seven cases were included for further analysis and matched to controls by the following characteristics: (1) site of occlusion, (2) result of the recanalization procedure according to the modified thrombolysis in cerebral infarction score, (3) administration of intravenous recombinant tissue plasminogen activator, (4) presence of proximal extracranial occlusion, (5) age, and (6) sex. Comparison of the angiographic data of the two cohorts showed no significant difference in the length of the procedures or the number of maneuvers needed for recanalization, nor were there significant differences in clinical outcomes as measured by NIHSS and mRS scores. Secondary symptomatic ICH occurred in one case in either cohort and led to death in both cases. The rate of asymptomatic ICH within the first 24h after recanalization was significantly higher in the group with peri-interventional SAH (57 vs. 0 %, P = 0.018). This small retrospective case-control study did not reveal a significant influence of peri-interventional SAH due to angiographically occult perforations on neurologic outcome of patients treated with stent retrievers.

Asteroid Rendezvous Mission Design Using Multiobjective Particle Swarm Optimization

A new preliminary trajectory design method for asteroid rendezvous mission using multiobjective optimization techniques is proposed. This method can overcome the disadvantages of the widely employed Pork-Chop method. The multiobjective integrated launch window and multi-impulse transfer trajectory design model is formulated, which employes minimum-fuel cost and minimum-time transfer as two objective functions. The multiobjective particle swarm optimization (MOPSO) is employed to locate the Pareto solution. The optimization results of two different asteroid mission designs show that the proposed approach can effectively and efficiently demonstrate the relations among the mission characteristic parameters such as launch time, transfer time, propellant cost, and number of maneuvers, which will provide very useful reference for practical asteroid mission design. Compared with the PCP method, the proposed approach is demonstrated to be able to provide much more easily used results, obtain better propellant-optimal solutions, and have much better efficiency. The MOPSO shows a very competitive performance with respect to the NSGA-II and the SPEA-II; besides a proposed boundary constraint optimization strategy is testified to be able to improve its performance.

A Multicenter Assessment of 1,177 Cases of Shoulder Dystocia: Lessons Learned

The purposes of this review were to describe deliveries complicated by shoulder dystocia (SD) at three tertiary centers and discern the differences between SD with and without brachial plexus injury (BPI). The inclusion criteria for this multicenter, retrospective study were singletons, delivered vaginally with SD. To discern the risk factors for SD with and without injury, a case (SD and BPI) versus control (3 SD without injury at the same institution) design was used. Multiple linear regression was employed. Over a 7-year period, among 46,637 vaginal deliveries, SD occurred in 1,177 cases (2.5%) and BPI was noted in 11%. The results of multiple regression indicate that gestational age, operative delivery, and the number of maneuvers and concomitant fracture (4%) were statistically associated with BPI following SD (p < 0.001). SD was not associated with BPI in 89% and 88% of the cases that were resolved with McRoberts maneuver and suprapubic pressure, whereas only 0.2% of cases were litigated.

A theoretical investigation into the handling characteristics of snowboards at low lateral acceleration

In this work, a model of a rider and snowboard is presented. The snowboard is modelled as two rigid one-dimensional sections connected by a frictionless pin-joint linked by a torsional stiffness and the rider by a mass at a fixed height above the snowboard, which can move longitudinally. The model is simplified to allow the fundamental behaviour of the snowboard and rider to be investigated for a number of manoeuvres used by learners. The behaviour of the rider is shown to be related to the angle of lean and it is conjectured that the rider might attempt to achieve consistency of response by moving their centre of mass longitudinally. The response of the model in open-loop is difficult to control, and to overcome this, two control loops are designed for the lateral velocity and yaw angle of the snowboard. The model is shown to recreate a number of manoeuvres that are used to help people to learn to ride snowboards.

A New Framework for Solving En Route Conflicts

The en route conflict resolution problem has been modeled in many different ways, generally depending on the tools proposed to solve it. For instance, with purely analytic mathematical solvers, models tend to be very restrictive to respect the inherent limitations of the technology.This paper introduces a new framework that separates the model from the solver so as to be able to: first, enhance the model with as many refinements as necessary to comply with operational constraints; second, compare different resolution methods on the same data, which is a crucial aspect of scientific research.To this aim, our framework generates a benchmark of conflict resolution problems built with various scenarios involving different numbers of aircraft, levels of uncertainties and numbers of maneuvers. We then compare two different optimization paradigms, Evolutionary Algorithm and Constraint Programming, which can efficiently solve difficult instances in near real time, to illustrate the usefulness of our approach.

Antegrade In Situ Stent-Graft Fenestration for the Renal Artery Following Inadvertent Coverage During EVAR

To report the use of antegrade in situ fenestration as a bailout technique to rescue a renal artery after inadvertent coverage during endovascular aneurysm repair (EVAR). The technique is demonstrated in a patient with a 6-cm infrarenal abdominal aortic aneurysm (AAA) and a short, angulated proximal neck. A type I endoleak persisted on completion angiography after implantation of a bifurcated Zenith stent-graft despite dilation with a compliant balloon. A Giant Palmaz stent mounted on a large compliant balloon successfully resolved the endoleak. After placing the stent, the left renal artery was covered completely by the main aortic graft material, leading to only marginal opacification on angiography. To preserve flow to the renal artery, a transseptal sheath and transseptal needle were introduced from the right femoral artery and used to puncture the abdominal stent-graft antegrade at the site of the left renal artery. A 0.018-inch guidewire could then be introduced into the left renal artery; following a number of maneuvers, a balloon-expandable stent was placed through the fenestration into the target vessel. On computed tomographic angiography 4 days postoperatively, the AAA remained excluded and both renal arteries were patent, with all side branches fully preserved. Renal function was completely restored. Antegrade in situ fenestration can facilitate immediate revascularization of inadvertently covered side branches in EVAR using a transseptal sheath and needle. If the anatomical features are supportive, antegrade in situ fenestration can be a useful bailout technique.

Minimum Fuel Low-Thrust Transfers for Satellites Using a Permanent Magnet Hall Thruster

Most of the satellite missions require orbital maneuvers to accomplish its goals. An orbital maneuver is an operation where the orbit of a satellite is changed, usually applying a type of propulsion. The maneuvers may have several purposes, such as the transfer of a satellite to its final orbit, the interception of another spacecraft, or the adjustment of the orbit to compensate the shifts caused by external forces. In this situation it is essential to minimize the fuel consumption to allow a greater number of maneuvers to be performed, and thus the lifetime of the satellite can be extended. There are several papers and studies which aim at the fuel minimization in maneuvers performed by space vehicles. In this context, this paper has two goals: (i) to develop an algorithm capable of finding optimal trajectories with continuous thrust that can fit different types of missions and constraints at the same time and (ii) to study the performance of two propulsion devices for orbital maneuvers under development at the Universidade de Brasilia, including a study of the effects of the errors in magnitude of these new devices.

Factors Influencing Human Errors during Work Permit Issuance by the Electric Power Transmission Network Operators

Prediction, identification, and control of errors effect on human performance and improve human actions. Human reliability has an important role in increasing the reliability of electricity production, transmission, and distribution networks and its direct/indirect damages. Right implementation of an effective work permit issuance system can meet safety of employees working in the control centre and other facilities and also can increase reliability of being used facilities. In the present research, effective factors for human errors in the process of work permit issuance by operators of control rooms working in the electricity transmission stations were studied. Substation operators' tasks, as the main human errors sources in the process of work permit issuance, were analyzed using hierarchical task analysis (HTA). Errors related to tasks were then predicted using systematic human error reduction and prediction (SHERPA) technique. The process of work permit issuance, as one of the main operators' tasks in which errors can be traced, was selected to analyze the impacts of some variables such as age, work experience, education level, hours of training, and number of maneuvers (number of permits issued by each operator). In the end, relationship between above variables and recorded errors was determined through Spearman's correlation coefficient. The results reveal that the action error and the error of maneuvering task have the most frequency respectively among the 107 predicted errors in six main tasks and 61 subtasks. The results also indicate a significant correlation (confidence level=95%) between the number of errors in the work permit issuance process and the Number of maneuvers (number of issued permits) (correlation coefficient=0.31&P=0), Training period (correlation coefficient=0.195&P=0.014), the work experience (correlation coefficient=0.191&P=0.016) and the age (correlation coefficient=0.164&p=0.014). There is also no significant correlation between the education level and the number of operator's errors in the work permit issuance process (correlation coefficient=-0.064&P=0.413). A reduction in human errors can be expected through the application of the identified factors effecting on operators' errors in power production and distribution networks.

Factors influencing human errors during work permit issuance by the electric power transmission network operators

Prediction, identification, and control of errors effect on human performance and improve human actions. Human reliability has an important role in increasing the reliability of electricity production, transmission, and distribution networks and its direct/indirect damages. Right implementation of an effective work permit issuance system can meet safety of employees working in the control centre and other facilities and also can increase reliability of being used facilities. In the present research, effective factors for human errors in the process of work permit issuance by operators of control rooms working in the electricity transmission stations were studied. Substation operators’ tasks, as the main human errors sources in the process of work permit issuance, were analyzed using hierarchical task analysis (HTA). Errors related to tasks were then predicted using systematic human error reduction and prediction (SHERPA) technique. The process of work permit issuance, as one of the main operators’ tasks in which errors can be traced, was selected to analyze the impacts of some variables such as age, work experience, education level, hours of training, and number of maneuvers (number of permits issued by each operator). In the end, relationship between above variables and recorded errors was determined through Spearman’s correlation coefficient. The results reveal that the action error and the error of maneuvering task have the most frequency respectively among the 107 predicted errors in six main tasks and 61 subtasks. The results also indicate a significant correlation (confidence level=95%) between the number of errors in the work permit issuance process and the Number of maneuvers (number of issued permits) (correlation coefficient=0.31 & P=0), Training period (correlation coefficient=0.195 & P=0.014), the work experience (correlation coefficient=0.191 & P=0.016) and the age (correlation coefficient=0.164 & p=0.014). There is also no significant correlation between the education level and the number of operator’s errors in the work permit issuance process (correlation coefficient=-0.064 & P=0.413). A reduction in human errors can be expected through the application of the identified factors effecting on operators’ errors in power production and distribution networks. Keywords: Operator, Work permit, Human error, HTA, SHERPA

Impulsive Control for Formation Flight About Libration Points

The concept of formation flight of multiple spacecraft, near the libration points of the sun-Earth system, offers many possibilities for space exploration. This study focuses on the use of impulsive control to maintain formation flight in the circular restricted three-body problem. Two specific tasks are accomplished in this paper. First, the tangent targeting method, based on a two-level differential correction, is formulated to fully exploit the predetermined error bound. A comparison between the tangent targeting method and traditional targeting method shows that the number of maneuvers can be significantly reduced and the length of time between successive maneuvers can be greatly increased by using the tangent targetingmethod. The study of the practical convergence of the algorithm is also discussed. The second task is the proposal of a tangent targeting method-based formationkeeping strategy for handling uncertainty introduced by the thrust implementation error. A tradeoff between the formation-keeping accuracy and the number of maneuvers is achieved. Monte Carlo analysis, including 100 trials, demonstrates the effectiveness of this strategy.

Benign paroxysmal positional vertigo of the posterior semicircular canal: efficacy of Santiago treatment protocol, long-term follow up and analysis of recurrence

To evaluate the efficacy of the Santiago treatment protocol for benign paroxysmal positional vertigo of the posterior semicircular canal, to analyse recurrence and to establish prognostic factors. Four hundred and twelve patients with unilateral benign paroxysmal positional vertigo of the posterior semicircular canal were treated with the Semont manoeuvre and, if symptoms did not resolve, successive application of three Epley manoeuvres plus Brandt-Daroff exercises. Symptoms resolved in 404 patients (98.1 per cent); a single Semont manoeuvre was sufficient in 334 (81.2 per cent). Aetiology had no impact on resolution of symptoms or number of manoeuvres required. The estimated likelihood of recurrence was 14 per cent in the first year and 27 per cent after 10 years. The only factor indicating a worse prognosis was recurrence. In unilateral benign paroxysmal positional vertigo of the posterior semicircular canal, the above treatment protocol cured 98 per cent of patients. More than half of recurrences occurred in the first year. None of the analysed factors increased the likelihood of recurrence.

A Randomized Comparison of the GlideScope Videolaryngoscope to the Standard Laryngoscopy for Intubation by Pediatric Residents in Simulated Easy and Difficult Infant Airway Scenarios

Videolaryngoscopy has been developed mainly to assist difficult airway intubation. However, there is a lack of studies demonstrating the real efficacy of its use in children. In this study, we tested the hypothesis that GlideScope (Verathon Inc, Bothell, Wash) videolaryngoscope improves tracheal intubation when used by pediatric residents in an advanced patient simulation model. Pediatric residents who passed a pediatric advanced life support course were eligible for the study. An advanced infant simulator was used, and 4 scenarios were proposed: normal airway (NA), tongue edema (TE), tongue edema and oropharyngeal edema, and cervical collar. No participant had prior experience with any videolaryngoscope. After a brief instruction in GlideScope technique, each participant performed the 4 scenarios using both the standard Miller and GlideScope laryngoscopes, in a random sequence. Sixteen residents were included. The number of failed intubations was higher with GlideScope in NA and TE scenarios (3 vs 0, in both cases). Mean (SD) time to successful intubation was significantly longer with GlideScope in the NA scenario (GlideScope, 38 [SD, 13] vs Miller, 26 [SD, 16] seconds; P = 0.043). The number of maneuvers was significantly higher with GlideScope in the tongue edema and oropharyngeal edema scenario (2.3 [SD, 1.5] vs 1.5 [SD, 1]; P = 0.04). Upper jaw injury index was significantly lower with GlideScope in NA (2.0 [SD, 1] vs 2.6 [SD, 0.8]; P = 0.008) and cervical collar (2.1 [SD, 1.0] vs 2.8 [SD, 0.5]; P = 0.011) scenarios. Participants considered GlideScope technique more difficult than standard Miller in NA (5 [SD, 2.0] vs 3 [SD, 1.3]; P = 0.04) and TE (5.9 [SD, 2.5] vs 3.9 [SD, 1.7]; P = 0.02) scenarios. In simulated scenarios of infant NA and difficult airway, when used by pediatric residents, GlideScope did not improve intubation performance when compared with the standard laryngoscope. Nevertheless, GlideScope may be safer for upper jaw injury and could have advantages in the management of complicated airway. Further studies are needed to assess if specific training will improve GlideScope intubation performance and whether the "in simulator" results translate into clinical practice.

Orbital rendezvous mission planning using mixed integer nonlinear programming

The rendezvous and docking mission is usually divided into several phases, and the mission planning is performed phase by phase. A new planning method using mixed integer nonlinear programming, which investigates single phase parameters and phase connecting parameters simultaneously, is proposed to improve the rendezvous mission’s overall performance. The design variables are composed of integers and continuous-valued numbers. The integer part consists of the parameters for station-keeping and sensor-switching, the number of maneuvers in each rendezvous phase and the number of repeating periods to start the rendezvous mission. The continuous part consists of the orbital transfer time and the station-keeping duration. The objective function is a combination of the propellant consumed, the sun angle which represents the power available, and the terminal precision of each rendezvous phase. The operational requirements for the spacecraft–ground communication, sun illumination and the sensor transition are considered. The simple genetic algorithm, which is a combination of the integer-coded and real-coded genetic algorithm, is chosen to obtain the optimal solution. A practical rendezvous mission planning problem is solved by the proposed method. The results show that the method proposed can solve the integral rendezvous mission planning problem effectively, and the solution obtained can satisfy the operational constraints and has a good overall performance.

Gravity-assisted maneuvers applied in the multi-objective optimization of interplanetary trajectories

In this work, the problem of optimization of interplanetary trajectories with minimum fuel consumption, but with a time limit is studied. It was used a methodology known as the Patched Conics, where the trajectory is divided into three parts: (1) departure phase, inside of the sphere of influence of the departure planet; (2) heliocentric phase, during the journey between the planets; and (3) arrival phase, inside of the sphere of influence of the arrival planet. Furthermore, the possibility of gravitational assisted maneuvers (swing-by) was considered to reduce fuel consumption. In this case the full trajectory would be divided into more parts, depending on the number of maneuvers. Therefore, the goal of this work is to find a combination of conical trajectories, using gravitational assisted maneuvers, which perform the transfer close to the departure planet to the vicinity of the arrival planet, spending minimal fuel with minimal time for the journey. Considering the minimization of time, the solution cannot be the solution of minimum fuel consumption, because the minimization of time and the minimization of fuel are conflicting objectives. Thus, a multi-objective problem must be solved. Hence, a methodology based on the Non Inferiority Criterion (Pareto, 1909 [2]) and the Smallest Loss Criterion (Rocco et al., 2002 [6]) was used, capable of considering multiple objectives simultaneously, without reducing the problem to the case of optimizing a single objective as occur in most methods found in the literature. A mission to Pluto, similar to NASA’s New Horizons Mission, was studied considering gravitational assisted maneuvers in Mars, Jupiter and Saturn. Simulating the trajectories and the maneuvers using the Transfer Trajectory Design Programs (Sukhanov, 2004 [13]), several possibilities were analyzed for many combinations of fuel consumption, time of departure, time of arrival and planet used for the swing-by. Then, using the Multi-objective Optimization Program (Rocco et al., 2002 [6]) the problem was solved seeking the best combination. The results can provide good assistance for mission analysis reducing the cost and time.

Flight Calibration of Flow Angularity Sensors on Tejas Using Advanced Parameter Estimation Techniques

Calibration of flow angularity sensors forms a very significant part of the flight tests carried out on a new aircraft. This paper describes the advanced parameter estimation techniques adopted for calibrating these sensors on Tejas. Flight path reconstruction procedures have been used to reconstruct the flight trajectories and compute the free stream Angle of Attack and Angle of Sideslip. The errors between measurements and the free stream values are then modeled. Optimization techniques are used to estimate the free parameters of the models to minimize the error. Flight data collated over a large number of maneuvers on seven different aircraft configurations have been used simultaneously. The results of the calibrations have been very consistent and typical results are presented in this paper.

Number of maneuvers need to get a negative Dix-Hallpike test

A Vertigem Postural Paroxistica Benigna e uma das causas mais comuns de tontura. Seu quadro clinico caracteristico e tontura ao movimentar a cabeca. A principal manobra diagnostica da Vertigem Postural Paroxistica Benigna de canal posterior e o teste de Dix-Hallpike. Se a manobra for positiva (presenca de vertigem e/ou nistagmo), indica-se realizar a manobra de reposicionamento de Epley do lado acometido OBJETIVO: Este trabalho tem como objetivo verificar o numero de manobras necessarias para a negativacao do teste de Dix-Hallpike em pacientes com Vertigem Postural Paroxistica Benigna de canal posterior. MATERIAL E METODO: Foi realizado uma analise retrospectiva de 71 prontuarios de pacientes com Vertigem Postural Paroxistica Benigna de canal posterior, os quais foram tratados com a manobra modificada de Epley. FORMA DE ESTUDO: Retrospectivo Transversal. RESULTADOS: Foi observado que 76,00% dos pacientes analisados tiveram resolucao completa dos sintomas e negativacao do teste de Dix-Hallpike com apenas uma manobra. CONCLUSAO: Diante destes resultados, podemos concluir que o numero de manobras modificadas de Epley e variavel de acordo com a etiologia, sendo que a Vertigem Postural Paroxistica Benigna secundaria ao traumatismo cranioencefalico necessitou de maior numero de manobras para a negativacao do teste de Dix-Hallpike.