Sample records for time-variant decompression model

  1. Non-linear time variant model intended for polypyrrole-based actuators (United States)

    Farajollahi, Meisam; Madden, John D. W.; Sassani, Farrokh


    Polypyrrole-based actuators are of interest due to their biocompatibility, low operation voltage and relatively high strain and force. Modeling and simulation are very important to predict the behaviour of each actuator. To develop an accurate model, we need to know the electro-chemo-mechanical specifications of the Polypyrrole. In this paper, the non-linear time-variant model of Polypyrrole film is derived and proposed using a combination of an RC transmission line model and a state space representation. The model incorporates the potential dependent ionic conductivity. A function of ionic conductivity of Polypyrrole vs. local charge is proposed and implemented in the non-linear model. Matching of the measured and simulated electrical response suggests that ionic conductivity of Polypyrrole decreases significantly at negative potential vs. silver/silver chloride and leads to reduced current in the cyclic voltammetry (CV) tests. The next stage is to relate the distributed charging of the polymer to actuation via the strain to charge ratio. Further work is also needed to identify ionic and electronic conductivities as well as capacitance as a function of oxidation state so that a fully predictive model can be created.

  2. Adaptive time-variant models for fuzzy-time-series forecasting. (United States)

    Wong, Wai-Keung; Bai, Enjian; Chu, Alice Wai-Ching


    A fuzzy time series has been applied to the prediction of enrollment, temperature, stock indices, and other domains. Related studies mainly focus on three factors, namely, the partition of discourse, the content of forecasting rules, and the methods of defuzzification, all of which greatly influence the prediction accuracy of forecasting models. These studies use fixed analysis window sizes for forecasting. In this paper, an adaptive time-variant fuzzy-time-series forecasting model (ATVF) is proposed to improve forecasting accuracy. The proposed model automatically adapts the analysis window size of fuzzy time series based on the prediction accuracy in the training phase and uses heuristic rules to generate forecasting values in the testing phase. The performance of the ATVF model is tested using both simulated and actual time series including the enrollments at the University of Alabama, Tuscaloosa, and the Taiwan Stock Exchange Capitalization Weighted Stock Index (TAIEX). The experiment results show that the proposed ATVF model achieves a significant improvement in forecasting accuracy as compared to other fuzzy-time-series forecasting models.

  3. Incorporating temporal variation in seabird telemetry data: time variant kernel density models (United States)

    Gilbert, Andrew; Adams, Evan M.; Anderson, Carl; Berlin, Alicia; Bowman, Timothy D.; Connelly, Emily; Gilliland, Scott; Gray, Carrie E.; Lepage, Christine; Meattey, Dustin; Montevecchi, William; Osenkowski, Jason; Savoy, Lucas; Stenhouse, Iain; Williams, Kathryn


    A key component of the Mid-Atlantic Baseline Studies project was tracking the individual movements of focal marine bird species (Red-throated Loon [Gavia stellata], Northern Gannet [Morus bassanus], and Surf Scoter [Melanitta perspicillata]) through the use of satellite telemetry. This element of the project was a collaborative effort with the Department of Energy (DOE), Bureau of Ocean Energy Management (BOEM), the U.S. Fish and Wildlife Service (USFWS), and Sea Duck Joint Venture (SDJV), among other organizations. Satellite telemetry is an effective and informative tool for understanding individual animal movement patterns, allowing researchers to mark an individual once, and thereafter follow the movements of the animal in space and time. Aggregating telemetry data from multiple individuals can provide information about the spatial use and temporal movements of populations. Tracking data is three dimensional, with the first two dimensions, X and Y, ordered along the third dimension, time. GIS software has many capabilities to store, analyze and visualize the location information, but little or no support for visualizing the temporal data, and tools for processing temporal data are lacking. We explored several ways of analyzing the movement patterns using the spatiotemporal data provided by satellite tags. Here, we present the results of one promising method: time-variant kernel density analysis (Keating and Cherry, 2009). The goal of this chapter is to demonstrate new methods in spatial analysis to visualize and interpret tracking data for a large number of individual birds across time in the mid-Atlantic study area and beyond. In this chapter, we placed greater emphasis on analytical methods than on the behavior and ecology of the animals tracked. For more detailed examinations of the ecology and wintering habitat use of the focal species in the midAtlantic, see Chapters 20-22.

  4. D1.4 -- Short Report on Models That Incorporate Non-stationary Time Variant Effects

    DEFF Research Database (Denmark)

    Lostanlen, Yves; Pedersen, Troels; Steinboeck, Gerhard

    -to-indoor environments are presented. Furthermore, the impact of human activity on the time variation of the radio channel is investigated and first simulation results are presented. Movement models, which include realistic interaction between nodes, are part of current research activities....

  5. A Log Logistic Survival Model Applied to Hypobaric Decompression Sickness (United States)

    Conkin, Johnny


    Decompression sickness (DCS) is a complex, multivariable problem. A mathematical description or model of the likelihood of DCS requires a large amount of quality research data, ideas on how to define a decompression dose using physical and physiological variables, and an appropriate analytical approach. It also requires a high-performance computer with specialized software. I have used published DCS data to develop my decompression doses, which are variants of equilibrium expressions for evolved gas plus other explanatory variables. My analytical approach is survival analysis, where the time of DCS occurrence is modeled. My conclusions can be applied to simple hypobaric decompressions - ascents lasting from 5 to 30 minutes - and, after minutes to hours, to denitrogenation (prebreathing). They are also applicable to long or short exposures, and can be used whether the sufferer of DCS is at rest or exercising at altitude. Ultimately I would like my models to be applied to astronauts to reduce the risk of DCS during spacewalks, as well as to future spaceflight crews on the Moon and Mars.

  6. A Time-Variant Reliability Model for Copper Bending Pipe under Seawater-Active Corrosion Based on the Stochastic Degradation Process

    Directory of Open Access Journals (Sweden)

    Bo Sun


    Full Text Available In the degradation process, the randomness and multiplicity of variables are difficult to describe by mathematical models. However, they are common in engineering and cannot be neglected, so it is necessary to study this issue in depth. In this paper, the copper bending pipe in seawater piping systems is taken as the analysis object, and the time-variant reliability is calculated by solving the interference of limit strength and maximum stress. We did degradation experiments and tensile experiments on copper material, and obtained the limit strength at each time. In addition, degradation experiments on copper bending pipe were done and the thickness at each time has been obtained, then the response of maximum stress was calculated by simulation. Further, with the help of one kind of Monte Carlo method we propose, the time-variant reliability of copper bending pipe was calculated based on the stochastic degradation process and interference theory. Compared with traditional methods and verified by maintenance records, the results show that the time-variant reliability model based on the stochastic degradation process proposed in this paper has better applicability in the reliability analysis, and it can be more convenient and accurate to predict the replacement cycle of copper bending pipe under seawater-active corrosion.

  7. Spinal decompression sickness: mechanical studies and a model. (United States)

    Hills, B A; James, P B


    Six experimental investigations of various mechanical aspects of the spinal cord are described relevant to its injury by gas deposited from solution by decompression. These show appreciable resistances to gas pockets dissipating by tracking along tissue boundaries or distending tissue, the back pressure often exceeding the probable blood perfusion pressure--particularly in the watershed zones. This leads to a simple mechanical model of spinal decompression sickness based on the vascular "waterfall" that is consistent with the pathology, the major quantitative aspects, and the symptomatology--especially the reversibility with recompression that is so difficult to explain by an embolic mechanism. The hypothesis is that autochthonous gas separating from solution in the spinal cord can reach sufficient local pressure to exceed the perfusion pressure and thus occlude blood flow.

  8. Development of a finite element model of decompressive craniectomy.

    Directory of Open Access Journals (Sweden)

    Tim L Fletcher

    Full Text Available Decompressive craniectomy (DC, an operation whereby part of the skull is removed, is used in the management of patients with brain swelling. While the aim of DC is to reduce intracranial pressure, there is the risk that brain deformation and mechanical strain associated with the operation could damage the brain tissue. The nature and extent of the resulting strain regime is poorly understood at present. Finite element (FE models of DC can provide insight into this applied strain and hence assist in deciding on the best surgical procedures. However there is uncertainty about how well these models match experimental data, which are difficult to obtain clinically. Hence there is a need to validate any modelling approach outside the clinical setting. This paper develops an axisymmetric FE model of an idealised DC to assess the key features of such an FE model which are needed for an accurate simulation of DC. The FE models are compared with an experimental model using gelatin hydrogel, which has similar poro-viscoelastic material property characteristics to brain tissue. Strain on a central plane of the FE model and the front face of the experimental model, deformation and load relaxation curves are compared between experiment and FE. Results show good agreement between the FE and experimental models, providing confidence in applying the proposed FE modelling approach to DC. Such a model should use material properties appropriate for brain tissue and include a more realistic whole head geometry.

  9. Identification of an Equivalent Linear Model for a Non-Linear Time-Variant RC-Structure

    DEFF Research Database (Denmark)

    Kirkegaard, Poul Henning; Andersen, P.; Brincker, Rune

    are investigated and compared with ARMAX models used on a running window. The techniques are evaluated using simulated data generated by the non-linear finite element program SARCOF modeling a 10-storey 3-bay concrete structure subjected to amplitude modulated Gaussian white noise filtered through a Kanai......This paper considers estimation of the maximum softening for a RC-structure subjected to earthquake excitation. The so-called Maximum Softening damage indicator relates the global damage state of the RC-structure to the relative decrease of the fundamental eigenfrequency in an equivalent linear...

  10. Modelling the time-variant dietary exposure of PCBs in China over the period 1930 to 2100. (United States)

    Zhao, Shizhen; Breivik, Knut; Jones, Kevin C; Sweetman, Andrew J


    This study aimed for the first time to reconstruct historical exposure profiles for PCBs to the Chinese population, by examining the combined effect of changing temporal emissions and dietary transition. A long-term (1930-2100) dynamic simulation of human exposure using realistic emission scenarios, including primary emissions, unintentional emissions and emissions from e-waste, combined with dietary transition trends was conducted by a multimedia fate model (BETR-Global) linked to a bioaccumulation model (ACC-HUMAN). The model predicted an approximate 30-year delay of peak body burden for PCB-153 in a 30-year-old Chinese female, compared to their European counterpart. This was mainly attributed to a combination of change in diet and divergent emission patterns in China. A fish-based diet was predicted to result in up to 8 times higher body burden than a vegetable-based diet (2010-2100). During the production period, a worst-case scenario assuming only consumption of imported food from a region with more extensive production and usage of PCBs would result in up to 4 times higher body burden compared to consumption of only locally produced food. However, such differences gradually diminished after cessation of production. Therefore, emission reductions in China alone may not be sufficient to protect human health for PCB-like chemicals, particularly during the period of mass production. The results from this study illustrate that human exposure is also likely to be dictated by inflows of PCBs via the environment, waste and food.

  11. A model for estimating time-variant rainfall infiltration as a function of antecedent surface moisture and hydrologic soil type (United States)

    Wilkening, H. A.; Ragan, R. M.


    Recent research indicates that the use of remote sensing techniques for the measurement of near surface soil moisture could be practical in the not too distant future. Other research shows that infiltration rates, especially for average or frequent rainfall events, are extremely sensitive to the proper definition and consideration of the role of the soil moisture at the beginning of the rainfall. Thus, it is important that an easy to use, but theoretically sound, rainfall infiltration model be available if the anticipated remotely sensed soil moisture data is to be optimally utilized for hydrologic simulation. A series of numerical experiments with the Richards' equation for an array of conditions anticipated in watershed hydrology were used to develop functional relationships that describe temporal infiltration rates as a function of soil type and initial moisture conditions.

  12. Persistent hemifacial spasm after microvascular decompression: a risk assessment model. (United States)

    Shah, Aalap; Horowitz, Michael


    Microvascular decompression (MVD) for hemifacial spasm (HFS) provides resolution of disabling symptoms such as eyelid twitching and muscle contractions of the entire hemiface. The primary aim of this study was to evaluate the predictive value of patient demographics and spasm characteristics on long-term outcomes, with or without intraoperative lateral spread response (LSR) as an additional variable in a risk assessment model. A retrospective study was undertaken to evaluate the associations of pre-operative patient characteristics, as well as intraoperative LSR and need for a staged procedure on the presence of persistent or recurrent HFS at the time of hospital discharge and at follow-up. A risk assessment model was constructed with the inclusion of six clinically or statistically significant variables from the univariate analyses. A receiving operator characteristic curve was generated, and area under the curve was calculated to determine the strength of the predictive model. A risk assessment model was first created consisting of significant pre-operative variables (Model 1) (age >50, female gender, history of botulinum toxin use, platysma muscle involvement). This model demonstrated borderline predictive value for persistent spasm at discharge (AUC .60; p=.045) and fair predictive value at follow-up (AUC .75; p=.001). Intraoperative variables (e.g. LSR persistence) demonstrated little additive value (Model 2) (AUC .67). Patients with a higher risk score (three or greater) demonstrated greater odds of persistent HFS at the time of discharge (OR 1.5 [95%CI 1.16-1.97]; p=.035), as well as greater odds of persistent or recurrent spasm at the time of follow-up (OR 3.0 [95%CI 1.52-5.95]; p=.002) Conclusions: A risk assessment model consisting of pre-operative clinical characteristics is useful in prognosticating HFS persistence at follow-up.

  13. Computed chest tomography in an animal model for decompression sickness: radiologic, physiologic, and pathologic findings

    International Nuclear Information System (INIS)

    Reuter, M.; Struck, N.; Heller, M.; Tetzlaff, K.; Brasch, F.; Mueller, K.M.; Gerriets, T.; Weiher, M.; Hansen, J.; Hirt, S.


    This study was conducted to investigate the early pulmonary effects of acute decompression in an animal model for human decompression sickness by CT and light microscopy. Ten test pigs were exposed to severe decompression stress in a chamber dive. Three pigs were kept at ambient pressure to serve as controls. Decompression stress was monitored by measurement of pulmonary artery pressure and arterial and venous Doppler recording of bubbles of inert gas. Chest CT was performed pre- and postdive and in addition the inflated lungs were examined after resection. Each lung was investigated by light microscopy. Hemodynamic data and bubble recordings reflected severe decompression stress in the ten test pigs. Computed tomography revealed large quantities of ectopic gas, predominantly intravascular, in three of ten pigs. These findings corresponded to maximum bubble counts in the Doppler study. The remaining test pigs showed lower bubble grades and no ectopic gas by CT. Sporadic interstitial edema was demonstrated in all animals - both test and control pigs - by CT of resected lungs and on histologic examination. A severe compression-decompression schedule can liberate large volumes of inert gas which are detectable by CT. Despite this severe decompression stress, which led to venous microembolism, CT and light microscopy did not demonstrate changes in lung structure related to the experimental dive. Increased extravascular lung water found in all animals may be due to infusion therapy. (orig.)

  14. A study on models of the inhomogeneity of the decompression in a bubble chamber

    International Nuclear Information System (INIS)

    Badier, J.


    Before building a hydrogen bubble chamber with liquid decompression the 'Saturne' cyclotron department wished to study for this chamber a shape leading to a homogeneous decompression as far as possible, without the production of vortices even after prolonged operation. The 'Office National d'Etudes et de Recherches Aeronautiques' (ONERA) were ready to carry out experiments on a model by strioscopy. The model was filled with air but an attempt was made to simulate the actual conditions as far as possible by varying the speed of the piston. The model was placed at one end of a tunnel, at the other end of which were produced alternatively compression and decompression waves. The study made it possible to conclude that it was necessary to make the base of the chamber round and that, in the space between the decompression cylinder and the body of the chamber it was advantageous to use 5 fins instead of 3. (author) [fr

  15. Time-variant reliability assessment through equivalent stochastic process transformation

    International Nuclear Information System (INIS)

    Wang, Zequn; Chen, Wei


    Time-variant reliability measures the probability that an engineering system successfully performs intended functions over a certain period of time under various sources of uncertainty. In practice, it is computationally prohibitive to propagate uncertainty in time-variant reliability assessment based on expensive or complex numerical models. This paper presents an equivalent stochastic process transformation approach for cost-effective prediction of reliability deterioration over the life cycle of an engineering system. To reduce the high dimensionality, a time-independent reliability model is developed by translating random processes and time parameters into random parameters in order to equivalently cover all potential failures that may occur during the time interval of interest. With the time-independent reliability model, an instantaneous failure surface is attained by using a Kriging-based surrogate model to identify all potential failure events. To enhance the efficacy of failure surface identification, a maximum confidence enhancement method is utilized to update the Kriging model sequentially. Then, the time-variant reliability is approximated using Monte Carlo simulations of the Kriging model where system failures over a time interval are predicted by the instantaneous failure surface. The results of two case studies demonstrate that the proposed approach is able to accurately predict the time evolution of system reliability while requiring much less computational efforts compared with the existing analytical approach. - Highlights: • Developed a new approach for time-variant reliability analysis. • Proposed a novel stochastic process transformation procedure to reduce the dimensionality. • Employed Kriging models with confidence-based adaptive sampling scheme to enhance computational efficiency. • The approach is effective for handling random process in time-variant reliability analysis. • Two case studies are used to demonstrate the efficacy

  16. Perfluorocarbon in Delayed Recompression with a Mixed Gender Swine Model of Decompression Sickness. (United States)

    Cronin, William A; Hall, Aaron A; Auker, Charles R; Mahon, Richard T


    Perfluorocarbons (PFC) are fluorinated hydrocarbons that dissolve gases to a much greater degree than plasma and hold promise in treating decompression sickness (DCS). The efficacy of PFC in a mixed gender model of DCS and safety in recompression therapy has not been previously explored. Swine (25 kg; N = 104; 51 male and 53 female) were randomized into normal saline solution (NSS) or PFC emulsion treatment groups and subjected to compression on air in a hyperbaric chamber at 200 fsw for 31 min. Then the animals were decompressed and observed for signs of DCS. Afterwards, they were treated with oxygen and either PFC (4 cc · kg-1) or NSS (4 cc · kg-1). Surviving animals were observed for 4 h, at which time they underwent recompression therapy using a standard Navy Treatment Table 6. After 24 h the animals were assessed and then euthanized. Survival rates were not significantly different between NSS (74.04%) and PFC (66.67%) treatment groups. All swine that received recompression treatment survived to the end of the study and no seizures were observed in either PFC or NSS animals. Within the saline treated swine group there were no significant differences in DCS survival between male (75.00%, N = 24) and female (73.08%, N = 26) swine. Within the PFC treated swine, survival of females (51.85%, N = 27) was significantly lower than males (81.48%, N = 27). In this large animal mixed gender efficacy study in DCS, PFC did not improve mortality or spinal cord injury, but appears safe during recompressive therapy. Gender differences in DCS treatment with PFC will need further study.Cronin WA, Hall AA, Auker CR, Mahon RT. Perfluorocarbon in delayed recompression with a mixed gender swine model of decompression sickness. Aerosp Med Hum Perform. 2018; 89(1):14-18.

  17. Forecasting Effusive Dynamics and Decompression Rates by Magmastatic Model at Open-vent Volcanoes. (United States)

    Ripepe, Maurizio; Pistolesi, Marco; Coppola, Diego; Delle Donne, Dario; Genco, Riccardo; Lacanna, Giorgio; Laiolo, Marco; Marchetti, Emanuele; Ulivieri, Giacomo; Valade, Sébastien


    Effusive eruptions at open-conduit volcanoes are interpreted as reactions to a disequilibrium induced by the increase in magma supply. By comparing four of the most recent effusive eruptions at Stromboli volcano (Italy), we show how the volumes of lava discharged during each eruption are linearly correlated to the topographic positions of the effusive vents. This correlation cannot be explained by an excess of pressure within a deep magma chamber and raises questions about the actual contributions of deep magma dynamics. We derive a general model based on the discharge of a shallow reservoir and the magmastatic crustal load above the vent, to explain the linear link. In addition, we show how the drastic transition from effusive to violent explosions can be related to different decompression rates. We suggest that a gravity-driven model can shed light on similar cases of lateral effusive eruptions in other volcanic systems and can provide evidence of the roles of slow decompression rates in triggering violent paroxysmal explosive eruptions, which occasionally punctuate the effusive phases at basaltic volcanoes.

  18. Performance comparison of various time variant filters

    Energy Technology Data Exchange (ETDEWEB)

    Kuwata, M [JEOL Engineering Co. Ltd., Akishima, Tokyo (Japan); Husimi, K


    This paper describes the advantage of the trapezoidal filter used in semiconductor detector system comparing with the other time variant filters. The trapezoidal filter is the compose of a rectangular pre-filter and a gated integrator. We indicate that the best performance is obtained by the differential-integral summing type rectangular pre-filter. This filter is not only superior in performance, but also has the useful feature that the rising edge of the output waveform is linear. We introduce an example of this feature used in a high-energy experiment. (author)

  19. Interactive virtual simulation using a 3D computer graphics model for microvascular decompression surgery. (United States)

    Oishi, Makoto; Fukuda, Masafumi; Hiraishi, Tetsuya; Yajima, Naoki; Sato, Yosuke; Fujii, Yukihiko


    The purpose of this paper is to report on the authors' advanced presurgical interactive virtual simulation technique using a 3D computer graphics model for microvascular decompression (MVD) surgery. The authors performed interactive virtual simulation prior to surgery in 26 patients with trigeminal neuralgia or hemifacial spasm. The 3D computer graphics models for interactive virtual simulation were composed of the brainstem, cerebellum, cranial nerves, vessels, and skull individually created by the image analysis, including segmentation, surface rendering, and data fusion for data collected by 3-T MRI and 64-row multidetector CT systems. Interactive virtual simulation was performed by employing novel computer-aided design software with manipulation of a haptic device to imitate the surgical procedures of bone drilling and retraction of the cerebellum. The findings were compared with intraoperative findings. In all patients, interactive virtual simulation provided detailed and realistic surgical perspectives, of sufficient quality, representing the lateral suboccipital route. The causes of trigeminal neuralgia or hemifacial spasm determined by observing 3D computer graphics models were concordant with those identified intraoperatively in 25 (96%) of 26 patients, which was a significantly higher rate than the 73% concordance rate (concordance in 19 of 26 patients) obtained by review of 2D images only (p computer graphics model provided a realistic environment for performing virtual simulations prior to MVD surgery and enabled us to ascertain complex microsurgical anatomy.

  20. A physiological model of the interaction between tissue bubbles and the formation of blood-borne bubbles under decompression

    International Nuclear Information System (INIS)

    Chappell, M A; Payne, S J


    Under decompression, bubbles can form in the human body, and these can be found both within the body tissues and the bloodstream. Mathematical models for the growth of both types of bubbles have previously been presented, but they have not been coupled together. This work thus explores the interaction between the growth of tissue and blood-borne bubbles under decompression, specifically looking at the extent to which they compete for the common resource of inert gas held in solution in the tissues. The influence of tissue bubbles is found to be significant for densities as low as 10 ml -1 for tissues which are poorly perfused. However, the effects of formation of bubbles in the blood are not found until the density of bubble production sites reaches 10 6 ml -1 . From comparison of the model predictions with experimental evidence for bubbles produced in animals and man under decompression, it is concluded that the density of tissue bubbles is likely to have a significant effect on the number of bubbles produced in the blood. However, the density of nucleation sites in the blood is unlikely to be sufficiently high in humans for the formation of bubbles in the blood to have a significant impact on the growth of the bubbles in the tissue

  1. F-15 inlet/engine test techniques and distortion methodologies studies. Volume 2: Time variant data quality analysis plots (United States)

    Stevens, C. H.; Spong, E. D.; Hammock, M. S.


    Time variant data quality analysis plots were used to determine if peak distortion data taken from a subscale inlet model can be used to predict peak distortion levels for a full scale flight test vehicle.

  2. Time-variant random interval natural frequency analysis of structures (United States)

    Wu, Binhua; Wu, Di; Gao, Wei; Song, Chongmin


    This paper presents a new robust method namely, unified interval Chebyshev-based random perturbation method, to tackle hybrid random interval structural natural frequency problem. In the proposed approach, random perturbation method is implemented to furnish the statistical features (i.e., mean and standard deviation) and Chebyshev surrogate model strategy is incorporated to formulate the statistical information of natural frequency with regards to the interval inputs. The comprehensive analysis framework combines the superiority of both methods in a way that computational cost is dramatically reduced. This presented method is thus capable of investigating the day-to-day based time-variant natural frequency of structures accurately and efficiently under concrete intrinsic creep effect with probabilistic and interval uncertain variables. The extreme bounds of the mean and standard deviation of natural frequency are captured through the embedded optimization strategy within the analysis procedure. Three particularly motivated numerical examples with progressive relationship in perspective of both structure type and uncertainty variables are demonstrated to justify the computational applicability, accuracy and efficiency of the proposed method.

  3. A new approach for reliability analysis with time-variant performance characteristics

    International Nuclear Information System (INIS)

    Wang, Zequn; Wang, Pingfeng


    Reliability represents safety level in industry practice and may variant due to time-variant operation condition and components deterioration throughout a product life-cycle. Thus, the capability to perform time-variant reliability analysis is of vital importance in practical engineering applications. This paper presents a new approach, referred to as nested extreme response surface (NERS), that can efficiently tackle time dependency issue in time-variant reliability analysis and enable to solve such problem by easily integrating with advanced time-independent tools. The key of the NERS approach is to build a nested response surface of time corresponding to the extreme value of the limit state function by employing Kriging model. To obtain the data for the Kriging model, the efficient global optimization technique is integrated with the NERS to extract the extreme time responses of the limit state function for any given system input. An adaptive response prediction and model maturation mechanism is developed based on mean square error (MSE) to concurrently improve the accuracy and computational efficiency of the proposed approach. With the nested response surface of time, the time-variant reliability analysis can be converted into the time-independent reliability analysis and existing advanced reliability analysis methods can be used. Three case studies are used to demonstrate the efficiency and accuracy of NERS approach

  4. Eco-reliable path finding in time-variant and stochastic networks

    International Nuclear Information System (INIS)

    Li, Wenjie; Yang, Lixing; Wang, Li; Zhou, Xuesong; Liu, Ronghui; Gao, Ziyou


    This paper addresses a route guidance problem for finding the most eco-reliable path in time-variant and stochastic networks such that travelers can arrive at the destination with the maximum on-time probability while meeting vehicle emission standards imposed by government regulators. To characterize the dynamics and randomness of transportation networks, the link travel times and emissions are assumed to be time-variant random variables correlated over the entire network. A 0–1 integer mathematical programming model is formulated to minimize the probability of late arrival by simultaneously considering the least expected emission constraint. Using the Lagrangian relaxation approach, the primal model is relaxed into a dualized model which is further decomposed into two simple sub-problems. A sub-gradient method is developed to reduce gaps between upper and lower bounds. Three sets of numerical experiments are tested to demonstrate the efficiency and performance of our proposed model and algorithm. - Highlights: • The most eco-reliable path is defined in time-variant and stochastic networks. • The model is developed with on-time arrival probability and emission constraints. • The sub-gradient and label correcting algorithm are integrated to solve the model. • Numerical experiments demonstrate the effectiveness of developed approaches.

  5. Decompression Mechanisms and Decompression Schedule Calculations. (United States)


    phisiology - The effects of altitude. Handbook of Physiology, Section 3: Respiration, Vol. II. W.O. Fenn and H. Rahn eds. Wash, D.C.; Am. Physiol. Soc. 1 4...decompression studies from other laboratories. METHODS Ten experienced and physically qualified divers ( ages 22-42) were compressed at a rate of 60...STATISTICS* --- ---------------------------------------------------------- EXPERIMENT N AGE (yr) HEIGHT (cm) WEIGHT (Kg) BODY FAT

  6. Development of an Operational Altitude Decompression Sickness Computer Model: Feasibility Study Results (United States)


    1955;36pp. 44. Eger El. II. A mathematical model of uptake and distribution, ch. 7, pp.72-87 In E. M. Papper and R. J. Kitz (eds.). Uptake and...Space Environ. Med. 1992;63:386. 119. Papper EM and Kitz RJ. Uptake and distribution of anesthetic agents. New York: McGraw Hill, 1963. 67 120. Per W and

  7. Relative device stability of anterior versus axillary needle decompression for tension pneumothorax during casualty movement: Preliminary analysis of a human cadaver model. (United States)

    Leatherman, Matthew L; Held, Jenny M; Fluke, Laura M; McEvoy, Christian S; Inaba, Kenji; Grabo, Daniel; Martin, Matthew J; Earley, Angela S; Ricca, Robert L; Polk, Travis M


    Tension pneumothorax (tPTX) remains a significant cause of potentially preventable death in military and civilian settings. The current prehospital standard of care for tPTX is immediate decompression with a 14-gauge 8-cm angiocatheter; however, failure rates may be as high as 17% to 60%. Alternative devices, such as 10-gauge angiocatheter, modified Veress needle, and laparoscopic trocar, have shown to be potentially more effective in animal models; however, little is known about the relative insertional safety or mechanical stability during casualty movement. Seven soft-embalmed cadavers were intubated and mechanically ventilated. Chest wall thickness was measured at the second intercostal space at the midclavicular line (2MCL) and the fifth intercostal space along the anterior axillary line (5AAL). CO2 insufflation created a PTX, and needle decompression was then performed with a randomized device. Insertional depth was measured between hub and skin before and after simulated casualty transport. Thoracoscopy was used to evaluate for intrapleural placement and/or injury during insertion and after movement. Cadaver demographics, device displacement, device dislodgment, and injuries were recorded. Three decompressions were performed at each site (2MCL/5AAL), totaling 12 events per cadaver. Eighty-four decompressions were performed. Average cadaver age was 59 years, and body mass index was 24 kg/m. The CWT varied between cadavers because of subcutaneous emphysema, but the average was 39 mm at the 2MCL and 31 mm at the 5AAL. Following movement, the 2MCL site was more likely to become dislodged than the 5AAL (67% vs. 17%, p = 0.001). Median displacement also differed between 2MCL and 5AAL (23 vs. 2 mm, p = 0.001). No significant differences were noted in dislodgement or displacement between devices. Five minor lung injuries were noted at the 5AAL position. Preliminary results from this human cadaver study suggest the 5AAL position is a more stable and reliable location

  8. Decompression illness - critical review

    Directory of Open Access Journals (Sweden)

    C S Mohanty


    Full Text Available Decompression illness is caused by intravascular or extravascular bubbles that are formed as a result of reduction in environmental pressure (decompression. The term covers both arterial gas embolism, in which alveolar gas or venous gas emboli (via cardiac shunts or via pulmonary vessels are introduced into the arterial circulation, and decompression sickness, which is caused by in-situ bubble formation from dissolved inert gas. Both syndromes can occur in divers, compressed air workers, aviators, and astronauts, but arterial gas embolism also arises from iatrogenic causes unrelated to decompression. Risk of decompression illness is affected by immersion, exercise, and heat or cold. Manifestations range from itching and minor pain to neurological symptoms, cardiac collapse, and death. First-aid treatment is 1 0 0 % oxygen and definitive treatment is recompression to increased pressure, breathing 1 0 0 % oxygen. Adjunctive treatment, including fluid administration and prophylaxis against venous thromboembolism in paralysed patients, is also recommended Treatment is, in most cases, effective although residual deficits can remain in serious cases, even after several recompressions.

  9. The effect of the perfluorocarbon emulsion Oxycyte on platelet count and function in the treatment of decompression sickness in a swine model. (United States)

    Cronin, William A; Senese, Angela L; Arnaud, Francoise G; Regis, David P; Auker, Charles R; Mahon, Richard T


    Decompression from elevated ambient pressure is associated with platelet activation and decreased platelet counts. Standard treatment for decompression sickness (DCS) is hyperbaric oxygen therapy. Intravenous perfluorocarbon (PFC) emulsion is a nonrecompressive therapy being examined that improves mortality in animal models of DCS. However, PFC emulsions are associated with a decreased platelet count. We used a swine model of DCS to study the effect of PFC therapy on platelet count, function, and hemostasis. Castrated male swine (n = 50) were fitted with a vascular port, recovered, randomized, and compressed to 180 feet of sea water (fsw) for 31 min followed by decompression at 30 fsw/min. Animals were observed for DCS, administered 100% oxygen, and treated with either emulsified PFC Oxycyte (DCS-PFC) or isotonic saline (DCS-NS). Controls underwent the same procedures, but were not compressed (Sham-PFC and Sham-NS). Measurements of platelet count, thromboelastometry, and coagulation were obtained 1 h before compression and 1, 24, 48, 96, 168 and 192 h after treatment. No significant changes in normalized platelet counts were observed. Prothrombin time was elevated in DCS-PFC from 48 to 192 h compared with DCS-NS, and from 96 to 192 h compared with Sham-PFC. Normalized activated partial thromboplastin time was also elevated in DCS-PFC from 168 to 192 h compared with Sham-PFC. No bleeding events were noted. DCS treated with PFC (Oxycyte) does not impact platelet numbers, whole blood clotting by thromboelastometry, or clinical bleeding. Late changes in prothrombin time and activated partial thromboplastin time associated with PFC use in both DCS therapy and controls warrant further investigation.

  10. Hybrid time-variant reliability estimation for active control structures under aleatory and epistemic uncertainties (United States)

    Wang, Lei; Xiong, Chuang; Wang, Xiaojun; Li, Yunlong; Xu, Menghui


    Considering that multi-source uncertainties from inherent nature as well as the external environment are unavoidable and severely affect the controller performance, the dynamic safety assessment with high confidence is of great significance for scientists and engineers. In view of this, the uncertainty quantification analysis and time-variant reliability estimation corresponding to the closed-loop control problems are conducted in this study under a mixture of random, interval, and convex uncertainties. By combining the state-space transformation and the natural set expansion, the boundary laws of controlled response histories are first confirmed with specific implementation of random items. For nonlinear cases, the collocation set methodology and fourth Rounge-Kutta algorithm are introduced as well. Enlightened by the first-passage model in random process theory as well as by the static probabilistic reliability ideas, a new definition of the hybrid time-variant reliability measurement is provided for the vibration control systems and the related solution details are further expounded. Two engineering examples are eventually presented to demonstrate the validity and applicability of the methodology developed.

  11. Imaging a Time-variant Earthquake Focal Region along an Interplate Boundary (United States)

    Tsuruga, K.; Kasahara, J.; Hasada, Y.; Fujii, N.


    We show a preliminary result of a trial for detecting a time-variant earthquake focal region along an interplate boundary by means of a new imaging method through a numerical simulation. Remarkable seismic reflections from the interplate boundaries of a subducting oceanic plate have been observed in Japan Trench (Mochizuki et al, 2005) and in Nankai Trough (Iidaka et al., 2003). Those strong seismic reflection existing in the current aseismic zones suggest the existence of fluid along the subduction boundary, and it is considered that they closely relate to a future huge earthquake. Seismic ACROSS has a potential to monitor some changes of transfer function along the propagating ray paths, by using an accurately-controlled transmission and receiving of the steady continuous signals repeatedly (Kumazawa et al., 2000). If the physical state in a focal region along the interplate would be changed enough in the time and space, for instance, by increasing or decreasing of fluid flow, we could detect some differences of the amplitude and/or travel-time of the particular reflection phases from the time-variant target region. In this study, we first investigated the seismic characteristics of seismograms and their differences before and after the change of a target region through a numerical simulation. Then, as one of the trials, we attempted to make an image of such time-variant target region by applying a finite-difference back-propagation technique in the time and space to the differences of waveforms (after Kasahara et al., 2010). We here used a 2-D seismic velocity model in the central Japan (Tsuruga et al., 2005), assuming a time-variant target region with a 200-m thickness along a subducting Philippine Sea plate at 30 km in depth. Seismograms were calculated at a 500-m interval for 260 km long by using FDM software (Larsen, 2000), in the case that P- and S-wave velocities (Vp amd Vs) in the target region decreased about 30 % before to after the change (e.g., Vp=3

  12. Flow Rate Through Pigtail Catheter Used for Left Heart Decompression in an Artificial Model of Extracorporeal Membrane Oxygenation Circuit. (United States)

    Kim, Won Ho; Hong, Tae Hee; Byun, Joung Hun; Kim, Jong Woo; Kim, Sung Hwan; Moon, Sung Ho; Park, Hyun Oh; Choi, Jun Young; Yang, Jun Ho; Jang, In Seok; Lee, Chung Eun; Yun, Jeong Hee

    In refractory cardiogenic shock, veno-arterial extracorporeal membrane oxygenation (ECMO) can be initiated. Although left heart decompression can be accomplished by insertion of a left atrial (LA) or left ventricular (LV) cannula using a percutaneous pigtail catheter, the venting flow rate according to catheter size and ECMO flow rate is unknown. We developed an artificial ECMO circuit. One liter saline bag with its pressure set to 20 mm Hg was connected to ECMO to mimic LV failure. A pigtail catheter was inserted into the 1 L saline bag to simulate LV unloading. For each pigtail catheter size (5-8 Fr) and ECMO flow rate (2.0-4.0 L/min), the moving distance of an air bubble that was injected through a three-way stopcock was measured in the arterial pressure line between the pigtail catheter and ECMO inflow limb. The flow rate was then calculated. We obtained the following equation to estimate the pigtail catheter flow rate.Pigtail vent catheter flow rate (ml/min) = 8×ECMOflow rate(L /min)+9×pigtail catheter size(Fr)- 57This equation would aid in designing of a further study to determine optimal venting flow rate. To achieve optimal venting flow, our equation would enable selection of an adequate catheter size.

  13. Quantum Dynamics of Multi Harmonic Oscillators Described by Time Variant Conic Hamiltonian and their Use in Contemporary Sciences

    International Nuclear Information System (INIS)

    Demiralp, Metin


    This work focuses on the dynamics of a system of quantum multi harmonic oscillators whose Hamiltonian is conic in positions and momenta with time variant coefficients. While it is simple, this system is useful for modeling the dynamics of a number of systems in contemporary sciences where the equations governing spatial or temporal changes are described by sets of ODEs. The dynamical causal models used readily in neuroscience can be indirectly described by these systems. In this work, we want to show that it is possible to describe these systems using quantum wave function type entities and expectations if the dynamic of the system is related to a set of ODEs.

  14. Decompression sickness in breath-hold divers: a review. (United States)

    Lemaitre, Frederic; Fahlman, Andreas; Gardette, Bernard; Kohshi, Kiyotaka


    Although it has been generally assumed that the risk of decompression sickness is virtually zero during a single breath-hold dive in humans, repeated dives may result in a cumulative increase in the tissue and blood nitrogen tension. Many species of marine mammals perform extensive foraging bouts with deep and long dives interspersed by a short surface interval, and some human divers regularly perform repeated dives to 30-40 m or a single dive to more than 200 m, all of which may result in nitrogen concentrations that elicit symptoms of decompression sickness. Neurological problems have been reported in humans after single or repeated dives and recent necropsy reports in stranded marine mammals were suggestive of decompression sickness-like symptoms. Modelling attempts have suggested that marine mammals may live permanently with elevated nitrogen concentrations and may be at risk when altering their dive behaviour. In humans, non-pathogenic bubbles have been recorded and symptoms of decompression sickness have been reported after repeated dives to modest depths. The mechanisms implicated in these accidents indicate that repeated breath-hold dives with short surface intervals are factors that predispose to decompression sickness. During deep diving, the effect of pulmonary shunts and/or lung collapse may play a major role in reducing the incidence of decompression sickness in humans and marine mammals.

  15. MAI-free performance of PMU-OFDM transceiver in time-variant environment (United States)

    Tadjpour, Layla; Tsai, Shang-Ho; Kuo, C.-C. J.


    An approximately multi-user OFDM transceiver was introduced to reduce the multi-access interference (MAI ) due to the carrier frequency offset (CFO) to a negligible amount via precoding by Tsai, Lin and Kuo. In this work, we investigate the performance of this precoded multi-user (PMU) OFDM system in a time-variant channel environment. We analyze and compare the MAI effect caused by time-variant channels in the PMU-OFDM and the OFDMA systems. Generally speaking, the MAI effect consists of two parts. The first part is due to the loss of orthogonality among subchannels for all users while the second part is due to the CFO effect caused by the Doppler shift. Simulation results show that, although OFDMA outperforms the PMU-OFDM transceiver in a fast time-variant environment without CFO, PMU-OFDM outperforms OFDMA in a slow time-variant channel via the use of M/2 symmetric or anti-symmetric codewords of M Hadamard-Walsh codes.

  16. Exploring Continuity of Care in Patients with Alcohol Use Disorders Using Time-Variant Measures

    NARCIS (Netherlands)

    S.C. de Vries (Sjoerd); A.I. Wierdsma (André)


    textabstractBackground/Aims: We used time-variant measures of continuity of care to study fluctuations in long-term treatment use by patients with alcohol-related disorders. Methods: Data on service use were extracted from the Psychiatric Case Register for the Rotterdam Region, The Netherlands.

  17. Advantages and Drawbacks of Applying Periodic Time-Variant Modal Analysis to Spur Gear Dynamics

    DEFF Research Database (Denmark)

    Pedersen, Rune; Santos, Ilmar; Hede, Ivan Arthur


    to ensure sufficient accuracy of the results. The method of time-variant modal analysis is applied, and the changes in the fundamental and the parametric resonance frequencies as a function of the rotational speed of the gears, are found. By obtaining the stationary and parametric parts of the time...... of applying the methodology to wind turbine gearboxes are addressed and elucidated....

  18. [Orbital decompression in Grave's ophtalmopathy]. (United States)

    Longueville, E


    Graves disease orbitopathy is a complex progressive inflammatory disease. Medical treatment remains in all cases the proposed treatment of choice. Surgical treatment by bone decompression can be considered as an emergency mainly in cases of optic neuropathy or ocular hypertension not being controlled medically or in post-traumatic exophthalmos stage. Emergency bone decompression eliminates compression or stretching of the optic nerve allowing visual recovery. The uncontrolled ocular hypertension will benefit from decompression. The normalization of intraocular pressure may be obtained by this surgery or if needed by the use of postoperative antiglaucoma drops or even filtration surgery. In all operated cases, the IOP was normalized with an average decrease of 7.71 mmHg and a cessation of eye drops in 3/7 cases. Regarding sequelae, our therapeutic strategy involves consecutively surgery of the orbit, extraocular muscles and eyelids. The orbital expansion gives excellent results on the cosmetic level and facilitates the implementation of subsequent actions.

  19. Evaluation of safety of hypobaric decompressions and EVA from positions of probabilistic theory (United States)

    Nikolaev, V. P.

    Formation and subsequent evolution of gas bubbles in blood and tissues of subjects exposed to decompression are casual processes in their nature. Such character of bubbling processes in a body predetermines probabilistic character of decompression sickness (DCS) incidence in divers, aviators and astronauts. Our original probabilistic theory of decompression safety is based on stochastic models of these processes and on the concept of critical volume of a free gas phase in body tissues. From positions of this theory, the probability of DCS incidence during single-stage decompressions and during hypobaric decompressions under EVA in particular, is defined by the distribution of possible values of nucleation efficiency in "pain" tissues and by its critical significance depended on the parameters of a concrete decompression. In the present study the following is shown: 1) the dimensionless index of critical nucleation efficiency for "pain" body tissues is a more adequate index of decompression stress in comparison with Tissue Ratio, TR; 2) a priory the decompression under EVA performed according to the Russian protocol is more safe than decompression under EVA performed in accordance with the U.S. protocol; 3) the Russian space suit operated at a higher pressure and having a higher "rigidity" induces a stronger inhibition of mechanisms of cavitation and gas bubbles formation in tissues of a subject located in it, and by that provides a more considerable reduction of the DCS risk during real EVA performance.

  20. Adaptive lattice decision-feedback equalizers - Their performance and application to time-variant multipath channnels (United States)

    Ling, F.; Proakis, J. G.


    This paper presents two types of adaptive lattice decision-feedback equalizers (DFE), the least squares (LS) lattice DFE and the gradient lattice DFE. Their performance has been investigated on both time-invariant and time-variant channels through computer simulations and compared to other kinds of equalizers. An analysis of the self-noise and tracking characteristics of the LS DFE and the DFE employing the Widrow-Hoff least mean square adaptive algorithm (LMS DFE) are also given. The analysis and simulation results show that the LS lattice DFE has the faster initial convergence rate, while the gradient lattice DFE is computationally more efficient. The main advantages of the lattice DFE's are their numerical stability, their computational efficiency, the flexibility to change their length, and their excellent capabilities for tracking rapidly time-variant channels.

  1. Dynamic Allan Variance Analysis Method with Time-Variant Window Length Based on Fuzzy Control

    Directory of Open Access Journals (Sweden)

    Shanshan Gu


    Full Text Available To solve the problem that dynamic Allan variance (DAVAR with fixed length of window cannot meet the identification accuracy requirement of fiber optic gyro (FOG signal over all time domains, a dynamic Allan variance analysis method with time-variant window length based on fuzzy control is proposed. According to the characteristic of FOG signal, a fuzzy controller with the inputs of the first and second derivatives of FOG signal is designed to estimate the window length of the DAVAR. Then the Allan variances of the signals during the time-variant window are simulated to obtain the DAVAR of the FOG signal to describe the dynamic characteristic of the time-varying FOG signal. Additionally, a performance evaluation index of the algorithm based on radar chart is proposed. Experiment results show that, compared with different fixed window lengths DAVAR methods, the change of FOG signal with time can be identified effectively and the evaluation index of performance can be enhanced by 30% at least by the DAVAR method with time-variant window length based on fuzzy control.

  2. Cardiopulmonary Changes with Moderate Decompression in Rats (United States)

    Robinson, R.; Little, T.; Doursout, M.-F.; Butler, B. D.; Chelly, J. E.


    Sprague-Dawley rats were compressed to 616 kPa for 120 min then decompressed at 38 kPa/min to assess the cardiovascular and pulmonary responses to moderate decompression stress. In one series of experiments the rats were chronically instrumented with Doppler ultrasonic probes for simultaneous measurement of blood pressure, cardiac output, heart rate, left and right ventricular wall thickening fraction, and venous bubble detection. Data were collected at base-line, throughout the compression/decompression protocol, and for 120 min post decompression. In a second series of experiments the pulmonary responses to the decompression protocol were evaluated in non-instrumented rats. Analyses included blood gases, pleural and bronchoalveolar lavage (BAL) protein and hemoglobin concentration, pulmonary edema, BAL and lung tissue phospholipids, lung compliance, and cell counts. Venous bubbles were directly observed in 90% of the rats where immediate post-decompression autopsy was performed and in 37% using implanted Doppler monitors. Cardiac output, stroke volume, and right ventricular wall thickening fractions were significantly decreased post decompression, whereas systemic vascular resistance was increased suggesting a decrease in venous return. BAL Hb and total protein levels were increased 0 and 60 min post decompression, pleural and plasma levels were unchanged. BAL white blood cells and neutrophil percentages were increased 0 and 60 min post decompression and pulmonary edema was detected. Venous bubbles produced with moderate decompression profiles give detectable cardiovascular and pulmonary responses in the rat.

  3. Physiotherapy after subacromial decompression surgery

    DEFF Research Database (Denmark)

    Christiansen, David Høyrup; Falla, Deborah; Frost, Poul


    This paper describes the development and details of a standardised physiotherapy exercise intervention designed to address pain and disability in patients with difficulty returning to usual activities after arthroscopic decompression surgery for subacromial impingement syndrome. To develop...... the intervention, the literature was reviewed with respect to the effectiveness of postoperative exercises, components of previous exercise programmes were extracted, and input from clinical physiotherapists in the field was obtained through a series of workshops. The physiotherapy exercise intervention...

  4. Thirty-five Day Fluoxetine Treatment Limits Sensory-Motor Deficit and Biochemical Disorders in a Rat Model of Decompression Sickness

    Directory of Open Access Journals (Sweden)

    Caroline Cosnard


    Full Text Available According to the OECD statistical base for 2014, anti-depressants will, on average, be distributed at a rate of 62 daily doses per 1,000 inhabitants for the 25 countries surveyed (Health at a glance: Europe 2014; OECD Health Statistics; World Health Organization and OECD Health Statistics, 2014. Divers must be concerned. On another hand, divers are potentially exposed to decompression sickness including coagulation inflammation and ischemia, which can result in neurological lesions or even death. The purpose of this study is to assess whether chronic treatment with anti-depressants may represent a contraindication to the practice of an at-risk activity, such as, scuba diving, or even presents a benefit by attenuating the severity of the symptoms. We study for the first time the effect of a 35-day fluoxetine treatment (20 mg/kg on the occurrence of decompression sickness in laboratory rats (n = 79. Following exposure to the hazardous protocol, there is a significant correlation between the type of treatment and the clinical status of the rats in favor of a better clinical prognosis for the rats treated with fluoxetine with a significantly higher number of No DCS status and a lower number of Severe DCS status in the Flux, compared to Controls. The treatment modifies the rat performances both significantly and favorably during the physical and behavioral tests, just like their biological and biochemical constants. After decompression, rats under treatment display lower sensory-motor deficit and lowers biochemical disorders. From a biological point of view, we conclude fluoxetine should not be seen as a contraindication for diving on the basis of anticipated increased physiological risk.

  5. Time variant layer control in atmospheric pressure chemical vapor deposition based growth of graphene

    KAUST Repository

    Qaisi, Ramy M.; Smith, Casey; Hussain, Muhammad Mustafa


    Graphene is a semi-metallic, transparent, atomic crystal structure material which is promising for its high mobility, strength and transparency - potentially applicable for radio frequency (RF) circuitry and energy harvesting and storage applications. Uniform (same number of layers), continuous (not torn or discontinuous), large area (100 mm to 200 mm wafer scale), low-cost, reliable growth are the first hand challenges for its commercialization prospect. We show a time variant uniform (layer control) growth of bi- to multi-layer graphene using atmospheric chemical vapor deposition system. We use Raman spectroscopy for physical characterization supported by electrical property analysis. © 2013 IEEE.

  6. Noise and signal processing in a microstrip detector with a time variant readout system

    International Nuclear Information System (INIS)

    Cattaneo, P.W.


    This paper treats the noise and signal processing by a time variant filter in a microstrip detector. In particular, the noise sources in the detector-electronics chain and the signal losses that cause a substantial decrease of the original signal are thoroughly analyzed. This work has been motivated by the analysis of the data of the microstrip detectors designed for the ALEPH minivertex detector. Hence, even if the discussion will be kept as general as possible, concrete examples will be presented referring to the specific ALEPH design. (orig.)

  7. Time variant layer control in atmospheric pressure chemical vapor deposition based growth of graphene

    KAUST Repository

    Qaisi, Ramy M.


    Graphene is a semi-metallic, transparent, atomic crystal structure material which is promising for its high mobility, strength and transparency - potentially applicable for radio frequency (RF) circuitry and energy harvesting and storage applications. Uniform (same number of layers), continuous (not torn or discontinuous), large area (100 mm to 200 mm wafer scale), low-cost, reliable growth are the first hand challenges for its commercialization prospect. We show a time variant uniform (layer control) growth of bi- to multi-layer graphene using atmospheric chemical vapor deposition system. We use Raman spectroscopy for physical characterization supported by electrical property analysis. © 2013 IEEE.

  8. The probability and severity of decompression sickness (United States)

    Hada, Ethan A.; Vann, Richard D.; Denoble, Petar J.


    Decompression sickness (DCS), which is caused by inert gas bubbles in tissues, is an injury of concern for scuba divers, compressed air workers, astronauts, and aviators. Case reports for 3322 air and N2-O2 dives, resulting in 190 DCS events, were retrospectively analyzed and the outcomes were scored as (1) serious neurological, (2) cardiopulmonary, (3) mild neurological, (4) pain, (5) lymphatic or skin, and (6) constitutional or nonspecific manifestations. Following standard U.S. Navy medical definitions, the data were grouped into mild—Type I (manifestations 4–6)–and serious–Type II (manifestations 1–3). Additionally, we considered an alternative grouping of mild–Type A (manifestations 3–6)–and serious–Type B (manifestations 1 and 2). The current U.S. Navy guidance allows for a 2% probability of mild DCS and a 0.1% probability of serious DCS. We developed a hierarchical trinomial (3-state) probabilistic DCS model that simultaneously predicts the probability of mild and serious DCS given a dive exposure. Both the Type I/II and Type A/B discriminations of mild and serious DCS resulted in a highly significant (p probability of ‘mild’ DCS resulted in a longer allowable bottom time for the same 2% limit. However, for the 0.1% serious DCS limit, we found a vastly decreased allowable bottom dive time for all dive depths. If the Type A/B scoring was assigned to outcome severity, the no decompression limits (NDL) for air dives were still controlled by the acceptable serious DCS risk limit rather than the acceptable mild DCS risk limit. However, in this case, longer NDL limits were allowed than with the Type I/II scoring. The trinomial model mild and serious probabilities agree reasonably well with the current air NDL only with the Type A/B scoring and when 0.2% risk of serious DCS is allowed. PMID:28296928

  9. Decompression sickness in caisson workers (United States)

    Ghawabi, Samir H. El; Mansour, Mohamed B.; Youssef, Fatma L.; Ghawabi, Mohamed H. El; Latif, Mohamed M. Abd El


    El Ghawabi, S. H., Mansour, M. B., Youssef, F. L., El Ghawabi, M. H., and Abd El Latif, M. M. (1971).Brit. J. industr. Med.,28, 323-329. Decompression sickness in caisson workers. An investigation of 55 bridge construction workers is reported. The overall bends rate was 0·97%. (The term `bends' as used in this study is defined in the paper.) Chokes were encountered in 67·27% of workers. A clinical, haematological, and radiological study was performed. Definite bony changes were found in 43·6% of all workers; 91·6% of these had lesions around the elbow. The presence of dense areas in the neck of the scapula is reported in two cases for the first time. The relatively high haematocrit value is thought to play a part in the pathogenesis of bone infarction through its relation with blood viscosity. Images PMID:5124832

  10. Time-variant partial directed coherence in analysis of the cardiovascular system. A methodological study

    International Nuclear Information System (INIS)

    Milde, T; Schwab, K; Walther, M; Eiselt, M; Witte, H; Schelenz, C; Voss, A


    Time-variant partial directed coherence (tvPDC) is used for the first time in a multivariate analysis of heart rate variability (HRV), respiratory movements (RMs) and (systolic) arterial blood pressure. It is shown that respiration-related HRV components which also occur at other frequencies besides the RM frequency (= respiratory sinus arrhythmia, RSA) can be identified. These additional components are known to be an effect of the 'half-the-mean-heart-rate-dilemma' ('cardiac aliasing' CA). These CA components may contaminate the entire frequency range of HRV and can lead to misinterpretation of the RSA analysis. TvPDC analysis of simulated and clinical data (full-term neonates and sedated patients) reveals these contamination effects and, in addition, the respiration-related CA components can be separated from the RSA component and the Traube–Hering–Mayer wave. It can be concluded that tvPDC can be beneficially applied to avoid misinterpretations in HRV analyses as well as to quantify partial correlative interaction properties between RM and RSA

  11. A Multistage Decision-Feedback Receiver Design for LTE Uplink in Mobile Time-Variant Environments

    Directory of Open Access Journals (Sweden)

    Juinn-Horng Deng


    Full Text Available Single-carrier-frequency division multiple access (SC-FDMA has recently become the preferred uplink transmission scheme in long-term evolution (LTE systems. Similar to orthogonal frequency division multiple access (OFDMA, SC-FDMA is highly sensitive to frequency offsets caused by oscillator inaccuracies and Doppler spread, which lead to intercarrier interference (ICI. This work proposes a multistage decision-feedback structure to mitigate the ICI effect and enhance system performance in time-variant environments. Based on the block-type pilot arrangement of the LTE uplink type 1 frame structure, the time-domain least squares (TDLS method and polynomial-based curve-fitting algorithm are employed for channel estimation. Instead of using a conventional equalizer, this work uses a group frequency-domain equalizer (GFDE to reduce computational complexity. Furthermore, this work utilizes a dual iterative structure of group parallel interference cancellation (GPIC and frequency-domain group parallel interference cancellation (FPIC to mitigate the ICI effect. Finally, to optimize system performance, this work applies a novel error-correction scheme. Simulation results demonstrate the bit error rate (BER performance is markedly superior to that of the conventional full-size receiver based on minimum mean square error (MMSE. This structure performs well and is a flexible choice in mobile environments using the SC-FDMA scheme.

  12. Microvascular decompression for trigeminal neuralgia

    International Nuclear Information System (INIS)

    Khan, S.A.; Khan, B.; Khan, A.A.; Afridi, E.A.A.; Mehmood, S.; Muhammad, G.; Hussain, I.; Zadran, K.K.; Bhatti, S.N.


    Background: Trigeminal Neuralgia (TGN) is the most frequently diagnosed type of facial pain. In idiopathic type of TGN it is caused by the neuro-vascular conflict involving trigeminal nerve. Microvascular decompression (MVD) aims at addressing this basic pathology in the idiopathic type of TGN. This study was conducted to determine the outcome and complications of patients with idiopathic TGN undergoing MVD. Method: In a descriptive case series patients with idiopathic TGN undergoing MVD were included in consecutive manner. Patients were diagnosed on the basis of detailed history and clinical examination. Retromastoid approach with craniectomy was used to access cerebellopontine angle (CP-angle) and microsurgical decompression was done. Patients were followed up for 6 months. Results: A total of 53 patients underwent MVD with mean age of 51.6±4.2 years and male predominance. In majority of cases (58.4 percentage) both Maxillary and Mandibular divisions were involved. Per-operatively superior cerebellar artery (SCA) was causing the neuro-vascular conflict in 33 (62.2 percentage) of the cases, anterior inferior cerebellar artery (AICA) in 6 (11.3 percentage) cases, both CSA and AICA in 3 (5.6 percentage) cases, venous compressions in only 1 (1.8percentage) patient and thick arachnoid adhesions were seen in 10 (18.9 percentage) patients. Postoperatively, 33 (68 percentage) patients were pain free, in 14 (26.45 percentage) patients pain was significantly improved whereas in 3 (5.6 percentage) patients there was mild improvement in symptoms. Three (5.6 percentage) patients did not improve after the primary surgery. Cerebrospinal fluid (CSF) leak was encountered in 7 (13.2 percentage) patients post-operatively, 4 (7.5 percentage) patients developed wound infection and 1 (1.8 percentage) patient developed aseptic meningitis. Three (5.6 percentage) patients had transient VII nerve palsy while one patient developed permanent VII nerve palsy. Conclusion: MVD is a safe and

  13. Report on computation of repetitive hyperbaric-hypobaric decompression tables (United States)

    Edel, P. O.


    The tables were constructed specifically for NASA's simulated weightlessness training program; they provide for 8 depth ranges covering depths from 7 to 47 FSW, with exposure times of 15 to 360 minutes. These tables were based up on an 8 compartment model using tissue half-time values of 5 to 360 minutes and Workmanline M-values for control of the decompression obligation resulting from hyperbaric exposures. Supersaturation ratios of 1.55:1 to 2:1 were used for control of ascents to altitude following such repetitive dives. Adequacy of the method and the resultant tables were determined in light of past experience with decompression involving hyperbaric-hypobaric interfaces in human exposures. Using these criteria, the method showed conformity with empirically determined values. In areas where a discrepancy existed, the tables would err in the direction of safety.

  14. A time-variant analysis of the 1/f^(2) phase noise in CMOS parallel LC-Tank quadrature oscillators

    DEFF Research Database (Denmark)

    Andreani, Pietro


    This paper presents a study of 1/f2 phase noise in quadrature oscillators built by connecting two differential LC-tank oscillators in a parallel fashion. The analysis clearly demonstrates the necessity of adopting a time-variant theory of phase noise, where a more simplistic, time...

  15. Delayed facial nerve decompression for Bell's palsy. (United States)

    Kim, Sang Hoon; Jung, Junyang; Lee, Jong Ha; Byun, Jae Yong; Park, Moon Suh; Yeo, Seung Geun


    Incomplete recovery of facial motor function continues to be long-term sequelae in some patients with Bell's palsy. The purpose of this study was to investigate the efficacy of transmastoid facial nerve decompression after steroid and antiviral treatment in patients with late stage Bell's palsy. Twelve patients underwent surgical decompression for Bell's palsy 21-70 days after onset, whereas 22 patients were followed up after steroid and antiviral therapy without decompression. Surgical criteria included greater than 90 % degeneration on electroneuronography and no voluntary electromyography potentials. This study was a retrospective study of electrodiagnostic data and medical chart review between 2006 and 2013. Recovery from facial palsy was assessed using the House-Brackmann grading system. Final recovery rate did not differ significantly in the two groups; however, all patients in the decompression group recovered to at least House-Brackmann grade III at final follow-up. Although postoperative hearing threshold was increased in both groups, there was no significant between group difference in hearing threshold. Transmastoid decompression of the facial nerve in patients with severe late stage Bell's palsy at risk for a poor facial nerve outcome reduced severe complications of facial palsy with minimal morbidity.

  16. Solutions to time variant problems of real-time expert systems (United States)

    Yeh, Show-Way; Wu, Chuan-Lin; Hung, Chaw-Kwei


    Real-time expert systems for monitoring and control are driven by input data which changes with time. One of the subtle problems of this field is the propagation of time variant problems from rule to rule. This propagation problem is even complicated under a multiprogramming environment where the expert system may issue test commands to the system to get data and to access time consuming devices to retrieve data for concurrent reasoning. Two approaches are used to handle the flood of input data. Snapshots can be taken to freeze the system from time to time. The expert system treats the system as a stationary one and traces changes by comparing consecutive snapshots. In the other approach, when an input is available, the rules associated with it are evaluated. For both approaches, if the premise condition of a fired rule is changed to being false, the downstream rules should be deactivated. If the status change is due to disappearance of a transient problem, actions taken by the fired downstream rules which are no longer true may need to be undone. If a downstream rule is being evaluated, it should not be fired. Three mechanisms for solving this problem are discussed: tracing, backward checking, and censor setting. In the forward tracing mechanism, when the premise conditions of a fired rule become false, the premise conditions of downstream rules which have been fired or are being evaluated due to the firing of that rule are reevaluated. A tree with its root at the rule being deactivated is traversed. In the backward checking mechanism, when a rule is being fired, the expert system checks back on the premise conditions of the upstream rules that result in evaluation of the rule to see whether it should be fired. The root of the tree being traversed is the rule being fired. In the censor setting mechanism, when a rule is to be evaluated, a censor is constructed based on the premise conditions of the upstream rules and the censor is evaluated just before the rule is

  17. Decompressive craniectomy in herpes simplex encephalitis

    Directory of Open Access Journals (Sweden)

    Muhammed Jasim Abdul Jalal


    Full Text Available Intracranial hypertension is a common cause of morbidity in herpes simplex encephalitis (HSE. HSE is the most common form of acute viral encephalitis. Hereby we report a case of HSE in which decompressive craniectomy was performed to treat refractory intracranial hypertension. A 32-year-old male presented with headache, vomiting, fever, and focal seizures involving the right upper limb. Cerebrospinal fluid-meningoencephalitic profile was positive for herpes simplex. Magnetic resonance image of the brain showed swollen and edematous right temporal lobe with increased signal in gray matter and subcortical white matter with loss of gray, white differentiation in T2-weighted sequences. Decompressive craniectomy was performed in view of refractory intracranial hypertension. Decompressive surgery for HSE with refractory hypertension can positively affect patient survival, with good outcomes in terms of cognitive functions.

  18. Surgical Decompression for Traumatic Spinal Cord Injury in a ...

    African Journals Online (AJOL)


    Jan 24, 2018 ... spinal cord decompression with or without spinal stabilization in our region. Methodology: We ... decompression and fixation in this series were surgical site infections (11.4%) and ..... group and died of respiratory failure.

  19. Relevance of control theory to design and maintenance problems in time-variant reliability: The case of stochastic viability

    International Nuclear Information System (INIS)

    Rougé, Charles; Mathias, Jean-Denis; Deffuant, Guillaume


    The goal of this paper is twofold: (1) to show that time-variant reliability and a branch of control theory called stochastic viability address similar problems with different points of view, and (2) to demonstrate the relevance of concepts and methods from stochastic viability in reliability problems. On the one hand, reliability aims at evaluating the probability of failure of a system subjected to uncertainty and stochasticity. On the other hand, viability aims at maintaining a controlled dynamical system within a survival set. When the dynamical system is stochastic, this work shows that a viability problem belongs to a specific class of design and maintenance problems in time-variant reliability. Dynamic programming, which is used for solving Markovian stochastic viability problems, then yields the set of design states for which there exists a maintenance strategy which guarantees reliability with a confidence level β for a given period of time T. Besides, it leads to a straightforward computation of the date of the first outcrossing, informing on when the system is most likely to fail. We illustrate this approach with a simple example of population dynamics, including a case where load increases with time. - Highlights: • Time-variant reliability tools cannot devise complex maintenance strategies. • Stochastic viability is a control theory that computes a probability of failure. • Some design and maintenance problems are stochastic viability problems. • Used in viability, dynamic programming can find reliable maintenance actions. • Confronting reliability and control theories such as viability is promising

  20. Spontaneous extracranial decompression of epidural hematoma

    International Nuclear Information System (INIS)

    Neely, John C.; Jones, Blaise V.; Crone, Kerry R.


    Epidural hematoma (EDH) is a common sequela of head trauma in children. An increasing number are managed nonsurgically, with close clinical and imaging observation. We report the case of a traumatic EDH that spontaneously decompressed into the subgaleal space, demonstrated on serial CT scans that showed resolution of the EDH and concurrent enlargement of the subgaleal hematoma. (orig.)

  1. Spontaneous extracranial decompression of epidural hematoma

    Energy Technology Data Exchange (ETDEWEB)

    Neely, John C. [Marshall University School of Medicine, Huntington, WV (United States); Jones, Blaise V. [Cincinnati Children' s Hospital Medical Center, Department of Radiology, Cincinnati, OH (United States); Crone, Kerry R. [Cincinnati Children' s Hospital Medical Center, Division of Neurosurgery, Cincinnati, OH (United States)


    Epidural hematoma (EDH) is a common sequela of head trauma in children. An increasing number are managed nonsurgically, with close clinical and imaging observation. We report the case of a traumatic EDH that spontaneously decompressed into the subgaleal space, demonstrated on serial CT scans that showed resolution of the EDH and concurrent enlargement of the subgaleal hematoma. (orig.)

  2. Decompressive craniectomy following brain injury: factors important ...

    African Journals Online (AJOL)


    Jan 7, 2010 ... Background: Decompressive craniectomy (DC) is often performed as an empirical lifesaving measure to protect the injured brain from the damaging effects of propagating oedema and intracranial hypertension. However, there are no clearly defined indications or specified guidelines for patient selection for ...

  3. Severe traumatic brain injury managed with decompressive ...

    African Journals Online (AJOL)


    May 29, 2012 ... Patients with severe taumatic brain injury may develop intractable raised ICP resulting in high mortality ... Glasgow coma score was 8/15 (E1V3M4) and he had left ... An emergency right fronto-temporo-parietal decompressive.

  4. Complications of cranioplasty after decompressive craniectomy

    Directory of Open Access Journals (Sweden)

    Maša Glišović


    Full Text Available Cranioplasty is a surgical repair of a defect or deformity of a skull with the use of autologous bone or synthetic materials.[4] It usually follows decompressive craniectomy, which is a commonly practiced neurosurgical intervention in patients with raised intracranial pressure unresponsive to other forms of treatment.[1] There are many conditions that may lead to intracranial hypertension, and the goal is to avoid brain necrosis caused by compartment pressure syndrome.[2] Consequently, the extensive use of decompressive craniectomy directly results in more cranioplasties, which sometimes present with unwanted complications.[5] Generally, the occurence of cranioplasty complications is between 16% and 34%.[3] Because of the many indications for craniectomy based on clinical data that speak in its favour, if will probably remain a relatively common neurosurgical intervention also in the future. The frequency of decompressive craniectomy and consequently of cranioplasty requires awareness of the many potential postoperative complications and understanding of its evolution. This article is a review of pathophysiological mechanisms after decompressive craniectomy and cranioplasty, of its complications and factors that potentially contribute to their occurence.

  5. A Pottery Electric Kiln Using Decompression (United States)

    Naoe, Nobuyuki; Yamada, Hirofumi; Nakayama, Tetsuo; Nakayama, Minoru; Minamide, Akiyuki; Takemata, Kazuya

    This paper presents a novel type electric kiln which fires the pottery using the decompression. The electric kiln is suitable for the environment and the energy saving as the pottery furnace. This paper described the baking principle and the baking characteristic of the novel type electric kiln.

  6. Pictorial essay: Role of ultrasound in failed carpal tunnel decompression

    Directory of Open Access Journals (Sweden)

    Rajesh Botchu


    Full Text Available USG has been used for the diagnosis of carpal tunnel syndrome. Scarring and incomplete decompression are the main causes for persistence or recurrence of symptoms. We performed a retrospective study to assess the role of ultrasound in failed carpal tunnel decompression. Of 422 USG studies of the wrist performed at our center over the last 5 years, 14 were for failed carpal tunnel decompression. Scarring was noted in three patients, incomplete decompression in two patients, synovitis in one patient, and an anomalous muscle belly in one patient. No abnormality was detected in seven patients. We present a pictorial review of USG findings in failed carpal tunnel decompression.

  7. Pictorial essay: Role of ultrasound in failed carpal tunnel decompression. (United States)

    Botchu, Rajesh; Khan, Aman; Jeyapalan, Kanagaratnam


    USG has been used for the diagnosis of carpal tunnel syndrome. Scarring and incomplete decompression are the main causes for persistence or recurrence of symptoms. We performed a retrospective study to assess the role of ultrasound in failed carpal tunnel decompression. Of 422 USG studies of the wrist performed at our center over the last 5 years, 14 were for failed carpal tunnel decompression. Scarring was noted in three patients, incomplete decompression in two patients, synovitis in one patient, and an anomalous muscle belly in one patient. No abnormality was detected in seven patients. We present a pictorial review of USG findings in failed carpal tunnel decompression.

  8. Magma decompression rates during explosive eruptions of Kīlauea volcano, Hawaii, recorded by melt embayments (United States)

    Ferguson, David J.; Gonnermann, Helge M.; Ruprecht, Philipp; Plank, Terry; Hauri, Erik H.; Houghton, Bruce F.; Swanson, Donald A.


    The decompression rate of magma as it ascends during volcanic eruptions is an important but poorly constrained parameter that controls many of the processes that influence eruptive behavior. In this study, we quantify decompression rates for basaltic magmas using volatile diffusion in olivine-hosted melt tubes (embayments) for three contrasting eruptions of Kīlauea volcano, Hawaii. Incomplete exsolution of H2O, CO2, and S from the embayment melts during eruptive ascent creates diffusion profiles that can be measured using microanalytical techniques, and then modeled to infer the average decompression rate. We obtain average rates of ~0.05-0.45 MPa s-1 for eruptions ranging from Hawaiian style fountains to basaltic subplinian, with the more intense eruptions having higher rates. The ascent timescales for these magmas vary from around ~5 to ~36 min from depths of ~2 to ~4 km, respectively. Decompression-exsolution models based on the embayment data also allow for an estimate of the mass fraction of pre-existing exsolved volatiles within the magma body. In the eruptions studied, this varies from 0.1 to 3.2 wt% but does not appear to be the key control on eruptive intensity. Our results do not support a direct link between the concentration of pre-eruptive volatiles and eruptive intensity; rather, they suggest that for these eruptions, decompression rates are proportional to independent estimates of mass discharge rate. Although the intensity of eruptions is defined by the discharge rate, based on the currently available dataset of embayment analyses, it does not appear to scale linearly with average decompression rate. This study demonstrates the utility of the embayment method for providing quantitative constraints on magma ascent during explosive basaltic eruptions.

  9. Patient-specific core decompression surgery for early-stage ischemic necrosis of the femoral head.

    Directory of Open Access Journals (Sweden)

    Wei Wang

    Full Text Available Core decompression is an efficient treatment for early stage ischemic necrosis of the femoral head. In conventional procedures, the pre-operative X-ray only shows one plane of the ischemic area, which often results in inaccurate drilling. This paper introduces a new method that uses computer-assisted technology and rapid prototyping to enhance drilling accuracy during core decompression surgeries and presents a validation study of cadaveric tests.Twelve cadaveric human femurs were used to simulate early-stage ischemic necrosis. The core decompression target at the anterolateral femoral head was simulated using an embedded glass ball (target. Three positioning Kirschner wires were drilled into the top and bottom of the large rotor. The specimen was then subjected to computed tomography (CT. A CT image of the specimen was imported into the Mimics software to construct a three-dimensional model including the target. The best core decompression channel was then designed using the 3D model. A navigational template for the specimen was designed using the Pro/E software and manufactured by rapid prototyping technology to guide the drilling channel. The specimen-specific navigation template was installed on the specimen using positioning Kirschner wires. Drilling was performed using a guide needle through the guiding hole on the templates. The distance between the end point of the guide needle and the target was measured to validate the patient-specific surgical accuracy.The average distance between the tip of the guide needle drilled through the guiding template and the target was 1.92±0.071 mm.Core decompression using a computer-rapid prototyping template is a reliable and accurate technique that could provide a new method of precision decompression for early-stage ischemic necrosis.

  10. Magma decompression rates during explosive eruptions of Kīlauea volcano, Hawaii, recorded by melt embayments (United States)

    Ferguson, David J.; Gonnermann, Helge M.; Ruprecht, Philipp; Plank, Terry; Hauri, Erik H.; Houghton, Bruce F.; Swanson, Donald A.


    The decompression rate of magma as it ascends during volcanic eruptions is an important but poorly constrained parameter that controls many of the processes that influence eruptive behavior. In this study, we quantify decompression rates for basaltic magmas using volatile diffusion in olivine-hosted melt tubes (embayments) for three contrasting eruptions of Kīlauea volcano, Hawaii. Incomplete exsolution of H2O, CO2, and S from the embayment melts during eruptive ascent creates diffusion profiles that can be measured using microanalytical techniques, and then modeled to infer the average decompression rate. We obtain average rates of ~0.05–0.45 MPa s−1 for eruptions ranging from Hawaiian style fountains to basaltic subplinian, with the more intense eruptions having higher rates. The ascent timescales for these magmas vary from around ~5 to ~36 min from depths of ~2 to ~4 km, respectively. Decompression-exsolution models based on the embayment data also allow for an estimate of the mass fraction of pre-existing exsolved volatiles within the magma body. In the eruptions studied, this varies from 0.1 to 3.2 wt% but does not appear to be the key control on eruptive intensity. Our results do not support a direct link between the concentration of pre-eruptive volatiles and eruptive intensity; rather, they suggest that for these eruptions, decompression rates are proportional to independent estimates of mass discharge rate. Although the intensity of eruptions is defined by the discharge rate, based on the currently available dataset of embayment analyses, it does not appear to scale linearly with average decompression rate. This study demonstrates the utility of the embayment method for providing quantitative constraints on magma ascent during explosive basaltic eruptions.

  11. Identifying the Subtle Presentation of Decompression Sickness. (United States)

    Alea, Kenneth


    Decompression sickness is an inherent occupational hazard that has the possibility to leave its victims with significant long-lasting effects that can potentially impact an aircrew's flight status. The relative infrequency of this hazard within the military flying community along with the potentially subtle presentation of decompression sickness (DCS) has the potential to result in delayed diagnosis and treatment, leading to residual deficits that can impact a patient's daily life or even lead to death. The patient presented in this work was diagnosed with a Type II DCS 21 h after a cabin decompression at 35,000 ft (10,668 m). The patient had been asymptomatic with a completely normal physical/neurological exam following his flight. The following day, he presented with excessive fatigue and on re-evaluation was recommended for hyperbaric therapy, during which his symptoms completely resolved. He was re-evaluated 14 d later and cleared to resume flight duties without further incident. The manifestation of this patient's decompression sickness was subtle and followed an evaluation that failed to identify any focal findings. A high index of suspicion with strict follow-up contributed to the identification of DCS in this case, resulting in definitive treatment and resolution of the patient's symptoms. Determination of the need for hyperbaric therapy following oxygen supplementation and a thorough history and physical is imperative. If the diagnosis is in question, consider preemptive hyperbaric therapy as the benefits of treatment in DCS outweigh the risks of treatment. Finally, this work introduces the future potential of neuropsychological testing for both the diagnosis of DCS as well as assessing the effectiveness of hyperbaric therapy in Type II DCS.

  12. Emergency percutaneous needle decompression for tension pneumoperitoneum

    Directory of Open Access Journals (Sweden)

    Körner Markus


    Full Text Available Abstract Background Tension pneumoperitoneum as a complication of iatrogenic bowel perforation during endoscopy is a dramatic condition in which intraperitoneal air under pressure causes hemodynamic and ventilatory compromise. Like tension pneumothorax, urgent intervention is required. Immediate surgical decompression though is not always possible due to the limitations of the preclinical management and sometimes to capacity constraints of medical staff and equipment in the clinic. Methods This is a retrospective analysis of cases of pneumoperitoneum and tension pneumoperitoneum due to iatrogenic bowel perforation. All patients admitted to our surgical department between January 2005 and October 2010 were included. Tension pneumoperitoneum was diagnosed in those patients presenting signs of hemodynamic and ventilatory compromise in addition to abdominal distension. Results Between January 2005 and October 2010 eleven patients with iatrogenic bowel perforation were admitted to our surgical department. The mean time between perforation and admission was 36 ± 14 hrs (range 30 min - 130 hrs, between ER admission and begin of the operation 3 hrs and 15 min ± 47 min (range 60 min - 9 hrs. Three out of eleven patients had clinical signs of tension pneumoperitoneum. In those patients emergency percutaneous needle decompression was performed with a 16G venous catheter. This improved significantly the patients' condition (stabilization of vital signs, reducing jugular vein congestion, bridging the time to the start of the operation. Conclusions Hemodynamical and respiratory compromise in addition to abdominal distension shortly after endoscopy are strongly suggestive of tension pneumoperitoneum due to iatrogenic bowel perforation. This is a rare but life threatening condition and it can be managed in a preclinical and clinical setting with emergency percutaneous needle decompression like tension pneumothorax. Emergency percutaneous decompression is no

  13. Time-variant flexural reliability of RC beams with externally bonded CFRP under combined fatigue-corrosion actions

    International Nuclear Information System (INIS)

    Bigaud, David; Ali, Osama


    Time-variant reliability analysis of RC highway bridges strengthened with carbon fibre reinforced polymer CFRP laminates under four possible competing damage modes (concrete crushing, steel rupture after yielding, CFRP rupture and FRP plate debonding) and three degradation factors is analyzed in terms of reliability index β using FORM. The first degradation factor is chloride-attack corrosion which induces reduction in steel area and concrete cover cracking at characteristic key times (corrosion initiation, severe surface cover cracking). The second degradation factor considered is fatigue which leads to damage in concrete and steel rebar. Interaction between corrosion and fatigue crack growth in steel reinforcing bars is implemented. The third degradation phenomenon is the CFRP properties deterioration due to aging. Considering these three degradation factors, the time-dependent flexural reliability profile of a typical simple 15 m-span intermediate girder of a RC highway bridge is constructed under various traffic volumes and under different corrosion environments. The bridge design options follow AASHTO-LRFD specifications. Results of the study have shown that the reliability is very sensitive to factors governing the corrosion. Concrete damage due to fatigue slightly affects reliability profile of non-strengthened section, while service life after strengthening is strongly related to fatigue damage in concrete. - Highlights: • We propose a method to follow the time-variant reliability of strengthened RC beams. • We consider multiple competing failure modes of CFRP strengthened RC beams. • We consider combined degradation mechanisms (corrosion, fatigue, ageing of CFRP)

  14. Comparative incidences of decompression illness in repetitive, staged, mixed-gas decompression diving: is 'dive fitness' an influencing factor? (United States)

    Sayer, Martin Dj; Akroyd, Jim; Williams, Guy D


    Wreck diving at Bikini Atoll consists of a relatively standard series of decompression dives with maximum depths in the region of 45-55 metres' sea water (msw). In a typical week of diving at Bikini, divers can perform up to 12 decompression dives to these depths over seven days; on five of those days, divers can perform two decompression dives per day. All the dives employ multi-level, staged decompression schedules using air and surface-supplied nitrox containing 80% oxygen. Bikini is serviced by a single diving operator and so a relatively precise record exists both of the actual number of dives undertaken and of the decompression illness incidents both for customer divers and the dive guides. The dive guides follow exactly the dive profiles and decompression schedules of the customers. Each dive guide will perform nearly 400 decompression dives a year, with maximum depths mostly around 50 msw, compared with an average of 10 (maximum of 12) undertaken typically by each customer diver in a week. The incidence of decompression illness for the customer population (presumed in the absence of medical records) is over ten times higher than that for the dive guides. The physiological reasons for such a marked difference are discussed in terms of customer demographics and dive-guide acclimatization to repetitive decompression stress. The rates of decompression illness for a range of diving populations are reviewed.

  15. Case Descriptions and Observations About Cutis Marmorata From Hypobaric Decompressions (United States)

    Conkin, Johnny; Pilmanis, Andrew A.; Webb, James T.


    There is disagreement about the pathophysiology, classification, and treatment of cutis marmorata (CM), so there is disagreement about the disposition and medical status of a person that had CM. CM is rare, associated with stressful decompressions, and may be associated with serious signs and symptoms of decompression sickness (DCS). CM presents as purple or bluish-red skin mottling, often in the pectoral region, shoulders, chest, or upper abdomen. It is unethical to induce CM in humans so all information comes from retrospective analysis of case reports, or from animal models. A literature search, seven recent case reports from the Johnson Space Center and Brooks Air Force Base Hypobaric DCS Databases, interviews with DCS treatment experts, and responses to surveys provided the factual information used to arrive at our conclusions and recommendations. The "weight of evidence" indicates that CM is a local, not centrally mediated or systemic response to bubbles. It is unclear whether obstruction of arterial or venous blood flow is the primary insult since the lesion is reported under either condition. Any neurological or cardiovascular involvements are coincidental, developing along the same time course. The skin could be the source of the bubbles due to its mass, the associated layer of fat, and the variable nature of skin blood flow. CM should not be categorized as Type II DCS, should be included with other skin manifestations in a category called cutaneous DCS, and hyperbaric treatment is only needed if ground level oxygen is ineffective in the case of altitude-induced CM.

  16. Mechanical reliability of structures subjected to time-variant physical phenomena

    International Nuclear Information System (INIS)

    Lemaire, Celine


    This work deals with two-phase critical flows in order to improve the way to dimension safety systems. It brings a numerical, physical and experimental contribution. We emphasized the importance to validate separately the numerical method and the physical model. Reference numerical solutions, assimilated to quasi-analytical solutions, were elaborated for a stationary one-dimensional restriction. They allowed to validate in space non stationary numerical schemes converged in time and constitute space convergence indicator (2 schemes validated). With this reliable numerical solution, we studied the physical model. The potential of a particular existing dispersed flow model has been validated thanks to experimental data. The validity domain of such a model is inevitably reduced. During this study, particular behaviors have been exhibited like the pseudo-critical nature of flow with a relaxation process, the non characteristic properties/nature of critical parameters where disequilibrium is largely reduced or the predominance of pressure due to interfacial transfers. The multidimensional aspect has been studied. A data base included local parameters corresponding to a simplify geometry has been constituted. The flow impact on the disk has been characterized and multidimensional effects identified. These effects form an additional step to the validation of multidimensional physical models. (author) [fr

  17. Redistribution of Decompression Stop Time from Shallow to Deep Stops Increases Incidence of Decompression Sickness in Air Decompression Dives (United States)


    year old active duty male diver surfaced from a 170/30 air dive at <corr>12:11<corr> on 24AUG06 using MK 20 FFM and following the A-2 “deep stops...effort, and this episode responded immediately to pressure. AGE is unlikely due to the experience of the diver, the MK 20 FFM characteristics, and...from a 170/30 air dive at <corr>12:11<corr> on 24AUG06 using MK 20 FFM and following the A-2 “deep stops” experimental decompression profile

  18. Testing viability of cross subsidy using time-variant price elasticities of industrial demand for electricity: Indian experience

    International Nuclear Information System (INIS)

    Chattopadhyay, Pradip


    Indian electric tariffs are characterized by very high rates for industrial and commercial classes to permit subsidized electric consumption by residential and agricultural customers. We investigate the viability of this policy using monthly data for 1997-2003 on electric consumption by a few large industrial customers under the aegis of a small distribution company in the state of Uttar Pradesh. For a given price/cost ratio, it can be shown that if the cross-subsidizing class' electricity demand is sufficiently elastic, increasing the class' rates fail to recover incremental cross-subsidy necessary to support additional revenues for subsidized classes. This suboptimality is tested by individually estimating time-variant price-elasticities of demand for these industrial customers using Box-Cox and linear regressions. We find that at least for some of these customers, cross-subsidy was suboptimal prior to as late as October 2001, when rates were changed following reforms

  19. Testing viability of cross subsidy using time-variant price elasticities of industrial demand for electricity: Indian experience

    Energy Technology Data Exchange (ETDEWEB)

    Chattopadhyay, Pradip [New Hampshire Public Utilities Commission, 21 South Fruit Street, Suite 10, Concord NH 03301 (United States)]. E-mail:


    Indian electric tariffs are characterized by very high rates for industrial and commercial classes to permit subsidized electric consumption by residential and agricultural customers. We investigate the viability of this policy using monthly data for 1997-2003 on electric consumption by a few large industrial customers under the aegis of a small distribution company in the state of Uttar Pradesh. For a given price/cost ratio, it can be shown that if the cross-subsidizing class' electricity demand is sufficiently elastic, increasing the class' rates fail to recover incremental cross-subsidy necessary to support additional revenues for subsidized classes. This suboptimality is tested by individually estimating time-variant price-elasticities of demand for these industrial customers using Box-Cox and linear regressions. We find that at least for some of these customers, cross-subsidy was suboptimal prior to as late as October 2001, when rates were changed following reforms.


    Directory of Open Access Journals (Sweden)

    M. M. Blagoveshchenskaia


    Full Text Available Summary. Specificity of a food manufacture demands perfection of automatic control systems of processes in devices, units and installations. Creation of an adaptive control system by technological process of a food on the basis of model of control object it is necessary to carry out the additional analysis for choice algorithm of identification on real enough to representative sample of input data and output signal/data. In article on the basis of simulation it is analyzed over 53 algorithms of recurrent identification plus the basic modifications of these algorithms by 47 criteria for time-varying multivariable linear dynamic objects. On the basis of this analysis for engineering practice for a considered class of objects some algorithms are recommended. Possibilities of the software suite having for today the fullest set of parametrical identification algorithms are discussed. For given specific conditions of comparison in the package identification algorithms for identification of stationary coefficients in the equation object of the most effective were: Yzerman-1, Kaczmarz, Nagumo-Noda, Rastrigin, Kalman filter, the forgetting factor, Zipkin. When pointwise object - Kaczmarz, Nagumo-Noda, Kalman filter; showed the best result identification algorithm-Nagumo Noda.

  1. New approaches for the reliability-oriented structural optimization considering time-variant aspects; Neue Ansaetze fuer die zuverlaessigkeitsorientierte Strukturoptimierung unter Beachtung zeitvarianter Aspekte

    Energy Technology Data Exchange (ETDEWEB)

    Kuschel, N.


    The optimization of structures with respect to cost, weight or performance is a well-known application of the nonlinear optimization. However reliability-based structural optimization has been subject of only very few studies. The approaches suggested up to now have been unsatisfactory regarding general possibility of application or easy handling by user. The objective of this thesis is the development of general approaches to solve both optimization problems, the minimization of cost with respect to constraint reliabilty and the maximization of reliability under cost constraint. The extented approach of an one-level-method will be introduced in detail for the time-invariant problems. Here, the reliability of the sturcture will be analysed in the framework of the First-Order-Reliability-Method (FORM). The use of time-variant reliability analysis is necessary for a realistic modelling of many practical problems. Therefore several generalizations of the new approaches will be derived for the time-variant reliability-based structural optimization. Some important properties of the optimization problems are proved. In addition some interesting extensions of the one-level-method, for example the cost optimization of structural series systems and the cost optimization in the frame of the Second-Order-Reliabiity-Method (SORM), are presented in the thesis. (orig.) [German] Die Optimierung von Tragwerken im Hinblick auf die Kosten, das Gewicht oder die Gestalt ist eine sehr bekannte Anwendung der nichtlinearen Optimierung. Die zuverlaessigkeitsorientierte Strukturoptimierung wurde dagegen weit seltener untersucht. Die bisher vorgeschlagenen Ansaetze koennen bezueglich ihrer allgemeinen Verwendbarkeit oder ihrer nutzerfreundlichen Handhabung nicht befriedigen. Das Ziel der vorliegenden Arbeit ist nun die Entwicklung allgemeiner Ansaetze zur Loesung der beiden Optimierungsprobleme, einer Kostenminimierung unter Zuverlaessigkeitsrestriktionen und einer

  2. Economic evaluation of decompressive craniectomy versus barbiturate coma for refractory intracranial hypertension following traumatic brain injury. (United States)

    Alali, Aziz S; Naimark, David M J; Wilson, Jefferson R; Fowler, Robert A; Scales, Damon C; Golan, Eyal; Mainprize, Todd G; Ray, Joel G; Nathens, Avery B


    Decompressive craniectomy and barbiturate coma are often used as second-tier strategies when intracranial hypertension following severe traumatic brain injury is refractory to first-line treatments. Uncertainty surrounds the decision to choose either treatment option. We investigated which strategy is more economically attractive in this context. We performed a cost-utility analysis. A Markov Monte Carlo microsimulation model with a life-long time horizon was created to compare quality-adjusted survival and cost of the two treatment strategies, from the perspective of healthcare payer. Model parameters were estimated from the literature. Two-dimensional simulation was used to incorporate parameter uncertainty into the model. Value of information analysis was conducted to identify major drivers of decision uncertainty and focus future research. Trauma centers in the United States. Base case was a population of patients (mean age = 25 yr) who developed refractory intracranial hypertension following traumatic brain injury. We compared two treatment strategies: decompressive craniectomy and barbiturate coma. Decompressive craniectomy was associated with an average gain of 1.5 quality-adjusted life years relative to barbiturate coma, with an incremental cost-effectiveness ratio of $9,565/quality-adjusted life year gained. Decompressive craniectomy resulted in a greater quality-adjusted life expectancy 86% of the time and was more cost-effective than barbiturate coma in 78% of cases if our willingness-to-pay threshold is $50,000/quality-adjusted life year and 82% of cases at a threshold of $100,000/quality-adjusted life year. At older age, decompressive craniectomy continued to increase survival but at higher cost (incremental cost-effectiveness ratio = $197,906/quality-adjusted life year at mean age = 85 yr). Based on available evidence, decompressive craniectomy for the treatment of refractory intracranial hypertension following traumatic brain injury provides better

  3. Cardiovascular Pressures with Venous Gas Embolism and Decompression (United States)

    Butler, B. D.; Robinson, R.; Sutton, T.; Kemper, G. B.


    Venous gas embolism (VGE) is reported with decompression to a decreased ambient pressure. With severe decompression, or in cases where an intracardiac septal defect (patent foramen ovale) exists, the venous bubbles can become arterialized and cause neurological decompression illness. Incidence rates of patent foramen ovale in the general population range from 25-34% and yet aviators, astronauts, and deepsea divers who have decompression-induced venous bubbles do not demonstrate neurological symptoms at these high rates. This apparent disparity may be attributable to the normal pressure gradient across the atria of the heart that must be reversed for there to be flow potency. We evaluated the effects of: venous gas embolism (0.025, 0.05 and 0.15 ml/ kg min for 180 min.) hyperbaric decompression; and hypobaric decompression on the pressure gradient across the left and right atria in anesthetized dogs with intact atrial septa. Left ventricular end-diastolic pressure was used as a measure of left atrial pressure. In a total of 92 experimental evaluations in 22 dogs, there were no reported reversals in the mean pressure gradient across the atria; a total of 3 transient reversals occurred during the peak pressure gradient changes. The reasons that decompression-induced venous bubbles do not consistently cause serious symptoms of decompression illness may be that the amount of venous gas does not always cause sufficient pressure reversal across a patent foramen ovale to cause arterialization of the venous bubbles.

  4. Collagen levels are normalized after decompression of experimentally obstructed colon

    DEFF Research Database (Denmark)

    Rehn, Martin; Ågren, Sven Per Magnus; Syk, I


    Our aim was to define the dynamics in collagen concentrations in the large bowel wall following decompression of experimental obstruction.......Our aim was to define the dynamics in collagen concentrations in the large bowel wall following decompression of experimental obstruction....

  5. Influence of Lumbar Lordosis on the Outcome of Decompression Surgery for Lumbar Canal Stenosis. (United States)

    Chang, Han Soo


    Although sagittal spinal balance plays an important role in spinal deformity surgery, its role in decompression surgery for lumbar canal stenosis is not well understood. To investigate the hypothesis that sagittal spinal balance also plays a role in decompression surgery for lumbar canal stenosis, a prospective cohort study analyzing the correlation between preoperative lumbar lordosis and outcome was performed. A cohort of 85 consecutive patients who underwent decompression for lumbar canal stenosis during the period 2007-2011 was analyzed. Standing lumbar x-rays and 36-item short form health survey questionnaires were obtained before and up to 2 years after surgery. Correlations between lumbar lordosis and 2 parameters of the 36-item short form health survey (average physical score and bodily pain score) were statistically analyzed using linear mixed effects models. There was a significant correlation between preoperative lumbar lordosis and the 2 outcome parameters at postoperative, 6-month, 1-year, and 2-year time points. A 10° increase of lumbar lordosis was associated with a 5-point improvement in average physical scores. This correlation was not present in preoperative scores. This study showed that preoperative lumbar lordosis significantly influences the outcome of decompression surgery on lumbar canal stenosis. Copyright © 2017 Elsevier Inc. All rights reserved.

  6. Feedback control of thermal instability by compression and decompression

    International Nuclear Information System (INIS)

    Okamoto, M.; Hirano, K.; Amano, T.; Ohnishi, M.


    Active feedback control of the fusion output power by means of plasma compression-decompression is considered with the purpose of achieving steady-state plasma ignition in a tokamak. A simple but realistic feedback control system is modelled and zero-dimensional energy balance equations are solved numerically by taking into account the errors in the measurements, a procedure that is necessary for the feedback control. It is shown that the control can stabilize the thermal runaway completely and maintain steady-state operation without any significant change in major radius or thermal output power. Linear stability is analysed for a general type of scaling law, and the dependence of the stability conditions on the scaling law is studied. The possibility of load-following operation is considered. Finally, a one-dimensional analysis is applied to the large-aspect-ratio case. (author)

  7. Needle Decompression of Tension Pneumothorax with Colorimetric Capnography. (United States)

    Naik, Nimesh D; Hernandez, Matthew C; Anderson, Jeff R; Ross, Erika K; Zielinski, Martin D; Aho, Johnathon M


    The success of needle decompression for tension pneumothorax is variable, and there are no objective measures assessing effective decompression. Colorimetric capnography, which detects carbon dioxide present within the pleural space, may serve as a simple test to assess effective needle decompression. Three swine underwent traumatically induced tension pneumothorax (standard of care, n = 15; standard of care with needle capnography, n = 15). Needle thoracostomy was performed with an 8-cm angiocatheter. Similarly, decompression was performed with the addition of colorimetric capnography. Subjective operator assessment of decompression was recorded and compared with true decompression, using thoracoscopic visualization for both techniques. Areas under receiver operating curves were calculated and pairwise comparison was performed to assess statistical significance (P pneumothorax, that is, the absence of any pathologic/space-occupying lesion, in 100% of cases (10 of 10 attempts). Standard of care needle decompression was detected by operators in 9 of 15 attempts (60%) and was detected in 3 of 10 attempts when tension pneumothorax was not present (30%). True decompression, under direct visualization with thoracoscopy, occurred 15 of 15 times (100%) with capnography, and 12 of 15 times (80%) without capnography. Areas under receiver operating curves were 0.65 for standard of care and 1.0 for needle capnography (P = .002). Needle decompression with colorimetric capnography provides a rapid, effective, and highly accurate method for eliminating operator bias for tension pneumothorax decompression. This may be useful for the treatment of this life-threatening condition. Copyright © 2017 American College of Chest Physicians. Published by Elsevier Inc. All rights reserved.

  8. [Decompression problems in diving in mountain lakes]. (United States)

    Bühlmann, A A


    The relationship between tolerated high-pressure tissue nitrogen and ambient pressure is practically linear. The tolerated nitrogen high pressure decreases at altitude, as the ambient pressure is lower. Additionally, tissues with short nitrogen half-times have a higher tolerance than tissues which retain nitrogen for longer duration. For the purpose of determining safe decompression routines, the human body can be regarded as consisting of 16 compartments with half-times from 4 to 635 minutes for nitrogen. The coefficients for calculation of the tolerated nitrogen-high pressure in the tissues can be deduced directly from the half-times for nitrogen. We show as application the results of 573 simulated air dives in the pressure-chamber and 544 real dives in mountain lakes in Switzerland (1400-2600 m above sea level) and in Lake Titicaca (3800 m above sea level). They are in accordance with the computed limits of tolerance.

  9. Magma degassing triggered by static decompression at Kīlauea Volcano, Hawai‘i (United States)

    Poland, Michael P.; Jeff, Sutton A.; Gerlach, Terrence M.


    During mid-June 2007, the summit of Kīlauea Volcano, Hawai‘i, deflated rapidly as magma drained from the subsurface to feed an east rift zone intrusion and eruption. Coincident with the deflation, summit SO2 emission rates rose by a factor of four before decaying to background levels over several weeks. We propose that SO2 release was triggered by static decompression caused by magma withdrawal from Kīlauea's shallow summit reservoir. Models of the deflation suggest a pressure drop of 0.5–3 MPa, which is sufficient to trigger exsolution of the observed excess SO2 from a relatively small volume of magma at the modeled source depth beneath Kīlauea's summit. Static decompression may also explain other episodes of deflation accompanied by heightened gas emission, including the precursory phases of Kīlauea's 2008 summit eruption. Hazards associated with unexpected volcanic gas emission argue for increased awareness of magma reservoir pressure fluctuations.

  10. 46 CFR 197.332 - PVHO-Decompression chambers. (United States)


    .... Each decompression chamber must— (a) Meet the requirements of § 197.328; (b) Have internal dimensions... pressure; (d) Have a means of operating all installed man-way locking devices, except disabled shipping...

  11. You’re the Flight Surgeon: Pulmonary Decompression Sickness (United States)


    follow-up of this patient Diagnosis: Decompression sickness (DeS) with pulmonary symptoms (Type Il DeS, older nomenclature). Treatment: Hyperbaric quite clear thai any case of suspected decompression sickness in the USAF be discussed with the hyperbariC medicine specialists at Brooks City...physician in as respectful manner as you can that you suspect the patient’s condition is likely related to his hypobaric exposure. B. Agree with

  12. Iso-risk air no decompression limits after scoring marginal decompression sickness cases as non-events. (United States)

    Murphy, F Gregory; Swingler, Ashleigh J; Gerth, Wayne A; Howle, Laurens E


    Decompression sickness (DCS) in humans is associated with reductions in ambient pressure that occur during diving, aviation, or certain manned spaceflight operations. Its signs and symptoms can include, but are not limited to, joint pain, radiating abdominal pain, paresthesia, dyspnea, general malaise, cognitive dysfunction, cardiopulmonary dysfunction, and death. Probabilistic models of DCS allow the probability of DCS incidence and time of occurrence during or after a given hyperbaric or hypobaric exposure to be predicted based on how the gas contents or gas bubble volumes vary in hypothetical tissue compartments during the exposure. These models are calibrated using data containing the pressure and respired gas histories of actual exposures, some of which resulted in DCS, some of which did not, and others in which the diagnosis of DCS was not clear. The latter are referred to as marginal DCS cases. In earlier works, a marginal DCS event was typically weighted as 0.1, with a full DCS event being weighted as 1.0, and a non-event being weighted as 0.0. Recent work has shown that marginal DCS events should be weighted as 0.0 when calibrating gas content models. We confirm this indication in the present work by showing that such models have improved performance when calibrated to data with marginal DCS events coded as non-events. Further, we investigate the ramifications of derating marginal events on model-prescribed air diving no-stop limits. Copyright © 2017 Elsevier Ltd. All rights reserved.

  13. Decompression to altitude: assumptions, experimental evidence, and future directions. (United States)

    Foster, Philip P; Butler, Bruce D


    Although differences exist, hypobaric and hyperbaric exposures share common physiological, biochemical, and clinical features, and their comparison may provide further insight into the mechanisms of decompression stress. Although altitude decompression illness (DCI) has been experienced by high-altitude Air Force pilots and is common in ground-based experiments simulating decompression profiles of extravehicular activities (EVAs) or astronauts' space walks, no case has been reported during actual EVAs in the non-weight-bearing microgravity environment of orbital space missions. We are uncertain whether gravity influences decompression outcomes via nitrogen tissue washout or via alterations related to skeletal muscle activity. However, robust experimental evidence demonstrated the role of skeletal muscle exercise, activities, and/or movement in bubble formation and DCI occurrence. Dualism of effects of exercise, positive or negative, on bubble formation and DCI is a striking feature in hypobaric exposure. Therefore, the discussion and the structure of this review are centered on those highlighted unresolved topics about the relationship between muscle activity, decompression, and microgravity. This article also provides, in the context of altitude decompression, an overview of the role of denitrogenation, metabolic gases, gas micronuclei, stabilization of bubbles, biochemical pathways activated by bubbles, nitric oxide, oxygen, anthropometric or physiological variables, Doppler-detectable bubbles, and potential arterialization of bubbles. These findings and uncertainties will produce further physiological challenges to solve in order to line up for the programmed human return to the Moon, the preparation for human exploration of Mars, and the EVAs implementation in a non-zero gravity environment.

  14. Piezosurgery in Modified Pterional Orbital Decompression Surgery in Graves Disease. (United States)

    Grauvogel, Juergen; Scheiwe, Christian; Masalha, Waseem; Jarc, Nadja; Grauvogel, Tanja; Beringer, Andreas


    Piezosurgery uses microvibrations to selectively cut bone, preserving the adjacent soft tissue. The present study evaluated the use of piezosurgery for bone removal in orbital decompression surgery in Graves disease via a modified pterional approach. A piezosurgical device (Piezosurgery medical) was used in 14 patients (20 orbits) with Graves disease who underwent orbital decompression surgery in additional to drills and rongeurs for bone removal of the lateral orbital wall and orbital roof. The practicability, benefits, and drawbacks of this technique in orbital decompression surgery were recorded. Piezosurgery was evaluated with respect to safety, preciseness of bone cutting, and preservation of the adjacent dura and periorbita. Preoperative and postoperative clinical outcome data were assessed. The orbital decompression surgery was successful in all 20 orbits, with good clinical outcomes and no postoperative complications. Piezosurgery proved to be a safe tool, allowing selective bone cutting with no damage to the surrounding soft tissue structures. However, there were disadvantages concerning the intraoperative handling in the narrow space and the efficiency of bone removal was limited in the orbital decompression surgery compared with drills. Piezosurgery proved to be a useful tool in bone removal for orbital decompression in Graves disease. It is safe and easy to perform, without any danger of damage to adjacent tissue because of its selective bone-cutting properties. Nonetheless, further development of the device is necessary to overcome the disadvantages in intraoperative handling and the reduced bone removal rate. Copyright © 2017 Elsevier Inc. All rights reserved.

  15. Decompressive craniectomy and CSF disorders in children. (United States)

    Manfiotto, Marie; Mottolese, Carmine; Szathmari, Alexandru; Beuriat, Pierre-Aurelien; Klein, Olivier; Vinchon, Matthieu; Gimbert, Edouard; Roujeau, Thomas; Scavarda, Didier; Zerah, Michel; Di Rocco, Federico


    Decompressive craniectomy (DC) is a lifesaving procedure but is associated to several post-operative complications, namely cerebrospinal fluid (CSF) dynamics impairment. The aim of this multicentric study was to evaluate the incidence of such CSF alterations after DC and review their impact on the overall outcome. We performed a retrospective multicentric study to analyze the CSF disorders occurring in children aged from 0 to 17 years who had undergone a DC for traumatic brain injury (TBI) in the major Departments of Pediatric Neurosurgery of France between January 2006 and August 2016. Out of 150 children, ranging in age between 7 months and 17 years, mean 10.75 years, who underwent a DC for TBI in 10 French pediatric neurosurgical centers. Sixteen (6 males, 10 females) (10.67%) developed CSF disorders following the surgical procedure and required an extrathecal CSF shunting. External ventricular drainage increased the risk of further complications, especially cranioplasty infection (p = 0.008). CSF disorders affect a minority of children after DC for TBI. They may develop early after the DC but they may develop several months after the cranioplasty (8 months), consequently indicating the necessity of clinical and radiological close follow-up after discharge from the neurosurgical unit. External ventricular drainage and permanent CSF shunt placement increase significantly the risk of cranioplasty infection.

  16. Quantifying the role of vegetation in controlling the time-variant age of evapotranspiration, soil water and stream flow (United States)

    Smith, A.; Tetzlaff, D.; Soulsby, C.


    Identifying the sources of water which sustain plant water uptake is an essential prerequisite to understanding the interactions of vegetation and water within the critical zone. Estimating the sources of root-water uptake is complicated by ecohydrological separation, or the notion of "two-water worlds" which distinguishes more mobile and immobile water sources which respectively sustain streamflow and evapotranspiration. Water mobility within the soil determines both the transit time/residence time of water through/in soils and the subsequent age of root-uptake and xylem water. We used time-variant StorAge Selection (SAS) functions to conceptualise the transit/residence times in the critical zone using a dual-storage soil column differentiating gravity (mobile) and tension dependent (immobile) water, calibrated to measured stable isotope signatures of soil water. Storage-discharge relationships [Brutsaert and Nieber, 1977] were used to identify gravity and tension dependent storages. A temporally variable distribution for root water uptake was identified using simulated stable isotopes in xylem and soil water. Composition of δ2H and δ18O was measured in soil water at 4 depths (5, 10, 15, and 20 cm) on 10 occasions, and 5 times for xylem water within the dominant heather (Calluna sp. and Erica sp.) vegetation in a Scottish Highland catchment over a two-year period. Within a 50 cm soil column, we found that more than 53% of the total stored water was water that was present before the start of the simulation. Mean residence times of the mobile water in the upper 20 cm of the soil were 16, 25, 36, and 44 days, respectively. Mean evaporation transit time varied between 9 and 40 days, driven by seasonal changes and precipitation events. Lastly, mean transit times of xylem water ranged between 95-205 days, driven by changes in soil moisture. During low soil moisture (i.e. lower than mean soil moisture), root-uptake was from lower depths, while higher than mean soil

  17. Ultrastructural changes of compressed lumbar ventral nerve roots following decompression

    International Nuclear Information System (INIS)

    El-Barrany, Wagih G.; Hamdy, Raid M.; Al-Hayani, Abdulmonem A.; Jalalah, Sawsan M.; Al-Sayyad, Mohammad J.


    To study whether there will be permanent lumbar nerve rot scanning or degeneration secondary to continuous compression followed by decompression on the nerve roots, which can account for postlaminectomy leg weakness or back pain. The study was performed at the Department of Anatomy, Faulty of Medicine, king Abdulaziz University, Jeddah, Kingdom of Saudi Arabia during 2003-2005. Twenty-six adult male New Zealand rabbits were used in the present study. The ventral roots of the left fourth lumbar nerve were clamped for 2 weeks then decompression was allowed by removal of the clips. The left ventral roots of the fourth lumbar nerve were excised for electron microscopic study. One week after nerve root decompression, the ventral root peripheral to the site of compression showed signs of Wallerian degeneration together with signs of regeneration. Schwann cells and myelinated nerve fibers showed severe degenerative changes. Two weeks after decompression, the endoneurium of the ventral root showed extensive edema with an increase in the regenerating myelinated and unmyentilated nerve fibers, and fibroblasts proliferation. Three weeks after decompression, the endoneurium showed an increase in the regenerating myelinated and unmyelinated nerve fibers with diminution of the endoneurial edema, and number of macrophages and an increase in collagen fibrils. Five and 6 weeks after decompression, the endoneurium showed marked diminution of the edema, macrophages, mast cells and fibroblasts. The enoneurium was filed of myelinated and unmyelinated nerve fibers and collagen fibrils. Decompression of the compressed roots of a spinal nerve is followed by regeneration of the nerve fibers and nerve and nerve recovery without endoneurial scarring. (author)

  18. Dysphonia and dysphagia after anterior cervical decompression. (United States)

    Tervonen, Hanna; Niemelä, Mika; Lauri, Eija-Riitta; Back, Leif; Juvas, Anja; Räsänen, Pirjo; Roine, Risto P; Sintonen, Harri; Salmi, Tapani; Vilkman, S Erkki; Aaltonen, Leena-Maija


    In this paper, the authors investigate the effects of anterior cervical decompression (ACD) on swallowing and vocal function. The study comprised 114 patients who underwent ACD. The early group (50 patients) was examined immediately pre- and postoperatively, and the late group (64 patients) was examined at only 3 to 9 months postoperatively. Fifty age- and sex-matched patients from the Department of Otorhinolaryngology-Head and Neck Surgery who had not been intubated in the previous 5 years were used as a control group. All patients in the early and control groups were examined by a laryngologist; patients in the late group were examined by a laryngologist and a neurosurgeon. Videolaryngostroboscopy was performed in all members of the patient and control groups, and the function of the ninth through 12th cranial nerves were clinically evaluated. Data were collected concerning swallowing, voice quality, surgery results, and health-related quality of life. Patients with persistent dysphonia were referred for phoniatric evaluation and laryngeal electromyography (EMG). Those with persistent dysphagia underwent transoral endoscopic evaluation of swallowing function and videofluorography. Sixty percent of patients in the early group reported dysphonia and 69% reported dysphagia at the immediate postoperative visit. Unilateral vocal fold paresis occurred in 12%. The prevalence of both dysphonia and dysphagia decreased in both groups 3 to 9 months postoperatively. All six patients with vocal fold paresis in the early group recovered, and in the late group there were two cases of vocal fold paresis. The results of laryngeal EMG were abnormal in 14 of 16 patients with persistent dysphonia. Neither intraoperative factors nor age or sex had any effect on the occurrence of dysphonia, dysphagia, or vocal fold paresis. Most patients were satisfied with the surgical outcome. Dysphonia, dysphagia, and vocal fold paresis are common but usually transient complications of ACD

  19. Propranolol Effects on Decompression Sickness in a Simulated DISSUB Rescue in Swine. (United States)

    Forbes, Angela S; Regis, David P; Hall, Aaron A; Mahon, Richard T; Cronin, William A


    Disabled submarine (DISSUB) survivors may face elevated CO2 levels and inert gas saturation, putting them at risk for CO2 toxicity and decompression sickness (DCS). Propranolol was shown to reduce CO2 production in an experimental DISSUB model in humans but its effects on DCS in a DISSUB rescue scenario are unknown. A 100% oxygen prebreathe (OPB) reduces DCS incidence and severity and is incorporated into some DISSUB rescue protocols. We used a swine model of DISSUB rescue to study the effect of propranolol on DCS incidence and mortality with and without an OPB. In Experiment 1, male Yorkshire Swine (70 kg) were pressurized to 2.8 ATA for 22 h. Propranolol 1.0 mg · kg-1 (IV) was administered at 21.25 h. At 22 h, the animal was rapidly decompressed and observed for DCS type, onset time, and mortality. Experimental animals (N = 21; 69 ± 4.1 kg), PROP1.0, were compared to PROP1.0-OPB45 (N = 8; 69 ± 2.8 kg) with the same dive profile, except for a 45 min OPB prior to decompression. In Experiment 2, the same methodology was used with the following changes: swine pressurized to 2.8 ATA for 28 h; experimental group (N = 25; 67 ± 3.3 kg), PROP0.5 bis, propranolol 0.5 mg · kg-1 bis (twice) (IV) was administered at 22 h and 26 h. Control animals (N = 25; 67 ± 3.9 kg) received normal saline. OPB reduced mortality in PROP1.0-OBP45 compared to PROP1.0 (0% vs. 71%). PROP0.5 bis had increased mortality compared to CONTROL (60-% vs. 4%). Administration of beta blockers prior to saturation decompression appears to increase DCS and worsen mortality in a swine model; however, their effects in bounce diving remain unknown.Forbes AS, Regis DP, HallAA, Mahon RT, Cronin WA. Propranolol effects on decompression sickness in a simulated DISSUB rescue in swine. Aerosp Med Hum Perform. 2017; 88(4):385-391.

  20. Does smoking affect the outcomes of lumbar decompression surgery?

    Directory of Open Access Journals (Sweden)

    Mehta Radha


    Full Text Available Introduction: Lumbar decompressions and micro-discectomies are commonly performed non-complex spinal surgeries that do not involve the insertion of metalwork into the spine and are done for symptomatic disc prolapse and lumbar spinal stenosis, whereas complex-spinal surgery does require metalwork [1]. Studies of complex-spinal surgeries show that smoking has a significant negative impact on the outcome of the surgery [2] therefore, the cessation of smoking is advised prior to surgery [3]. There are evidences in the literature supportive as well as opposing this statement about continued smoking and poor outcome of decompressive spinal surgeries. Methods: We retrospectively reviewed 143 consecutive patients who have had either a micro-discectomy or a micro-decompression. Results: We found no statistical difference between smokers and non-smokers in the outcomes of lumbar decompression surgery. Both groups improved equally and significantly in terms of back pain, leg pain and functions. Out of 143 patients, only 2% more non-smokers had improved leg pain compared to smokers, 1% less non-smokers had improved back pain and 2% more non-smokers had an improved Oswestry Disability Index (ODI score. Discussion: We recommend that it is important to surgically treat both smokers and non-smokers in need of a lumbar spinal decompression.

  1. Failure rate of prehospital chest decompression after severe thoracic trauma. (United States)

    Kaserer, Alexander; Stein, Philipp; Simmen, Hans-Peter; Spahn, Donat R; Neuhaus, Valentin


    Chest decompression can be performed by different techniques, like needle thoracocentesis (NT), lateral thoracostomy (LT), or tube thoracostomy (TT). The aim of this study was to report the incidence of prehospital chest decompression and to analyse the effectiveness of these techniques. In this retrospective case series study, all medical records of adult trauma patients undergoing prehospital chest decompression and admitted to the resuscitation area of a level-1 trauma center between 2009 and 2015 were reviewed and analysed. Only descriptive statistics were applied. In a 6-year period 24 of 2261 (1.1%) trauma patients had prehospital chest decompression. Seventeen patients had NT, six patients TT, one patient NT as well as TT, and no patients had LT. Prehospital successful release of a tension pneumothorax was reported by the paramedics in 83% (5/6) with TT, whereas NT was effective in 18% only (3/17). In five CT scans all thoracocentesis needles were either removed or extrapleural, one patient had a tension pneumothorax, and two patients had no pneumothorax. No NT or TT related complications were reported during hospitalization. Prehospital NT or TT is infrequently attempted in trauma patients. Especially NT is associated with a high failure rate of more than 80%, potentially due to an inadequate ratio between chest wall thickness and catheter length as previously published as well as a possible different pathophysiological cause of respiratory distress. Therefore, TT may be considered already in the prehospital setting to retain sufficient pleural decompression upon admission. Copyright © 2016. Published by Elsevier Inc.

  2. Hydrocephalus after decompressive craniectomy for malignant hemispheric cerebral infarction. (United States)

    Wang, Qiang-Ping; Ma, Jun-Peng; Zhou, Zhang-Ming; Yang, Min; You, Chao


    Several studies have investigated the incidence and risk factors of hydrocephalus after decompressive craniectomy (DC) for malignant hemispheric cerebral infarction. However, the results are controversial. Therefore, the following is a retrospective cohort study to determine the incidence and risk factors of hydrocephalus after DC for malignant hemispheric cerebral infarction. From January 2004 to June 2014, patients at two medical centres in south-west China, who underwent DC for malignant hemispheric cerebral infarction, were included. The patients' clinical and radiologic findings were retrospectively reviewed. A chi-square test, Mann-Whitney U-test and logistic regression model were used to identify the risk factors. A total of 128 patients were included in the study. The incidence of ventriculomegaly and shunt-dependent hydrocephalus were 42.2% (54/128) and 14.8% (19/128), respectively. Lower preoperative Glasgow Coma Scale (GCS) score and presence of subarachnoid haemorrhage (SAH) were factors significantly associated with the development of post-operative hydrocephalus after DC. Cerebral infarction patients receiving DC have a moderate tendency to suffer from post-operative hydrocephalus. A poor GCS score and the presence of SAH were significantly associated with the development of hydrocephalus after DC.

  3. MRI diagnosis of acute spinal cord decompression sickness

    International Nuclear Information System (INIS)

    Tang Xiaofeng; Yuan Fengmei; Ma Heng; Xu Yongzhong; Gai Qingzhu; Wang Ying


    Objective: To describe MRI findings of acute spinal cord decompression sickness. Methods: MRI findings of 5 cases with clinical definite acute spinal cord decompression sickness were retrospectively analyzed. The main clinical informations included underwater performance history against regulations, short-term complete or incomplete spinal cord injury symptoms after fast going out of water, sensory disability and urinary and fecal incontinence, etc. Results: Spinal cord vacuole sign was found in all 5 cases. Iso-signal intensity (n=3), high signal intensity (n=1), and low signal intensity (n=1) was demonstrated on T 1 WI, and high signal intensity (n=5) was found on T 2 WI. Owl eye sign was detected in 3 cases, and lacune foci were seen in 2 cases. Conclusion: MRI findings of acute spinal cord decompression sickness had some characteristics, and it was easy to diagnose by combining diving history with clinical manifestations. (authors)

  4. Reasons for revision surgery after orbital decompression for Graves’ orbitopathy

    Directory of Open Access Journals (Sweden)

    Stefano Sellari-Franceschini


    Full Text Available Stefano Sellari-Franceschini1, Luca Muscatello1, Veronica Seccia1, Riccardo Lenzi1, Amelia Santoro1, Marco Nardi2, Barbara Mazzi3, Aldo Pinchera3, Claudio Marcocci31Department of Neuroscience, 1st ENT division, 2Ophthalmology Division, 3Department of Endocrinology and Metabolism, Orthopaedics and Traumatology, Occupational Medicine, University of Pisa, ItalyObjectives: An analysis of complications and causes of failure in orbital decompression necessitating a second operation.Methods: Between December 1992 and April 2007, 375 patients (719 orbits were operated on using various techniques. Fourteen patients were initially operated on in our unit: 8 (group A1 were re-operated on after a short time due to complications connected with the decompression operation, 7 (group A2 were operated on after some time due to recurrence of the illness or unsatisfactory decompression (one patient is in both group A1 and A2. Five patients (group B underwent a first operation elsewhere.Results: For group A1 the most serious complications were connected to the nasal approach. For group A2 the operations were performed either because of a neuropathy recurrence or for further proptosis reduction due to recurrence or patient dissatisfaction. Lack of preoperative data hinders conclusions about group B, apart from one patient where the operation had not resolved a serious optic neuropathy after decompression based on Olivari technique combined with three-wall operation according to Mourits and colleagues (1990.Conclusions: We can deduce from group A1 that extreme attention is necessary during endonasal access, from group A2 that balancing the eyes is advisable, sacrificing maximum proptosis reduction to gain greater patient satisfaction, and from group B that decompression of the orbital apex is fundamental in the case of neuropathy.Keywords: orbital decompression, Graves’ orbitopathy, revision surgery

  5. The incidence of diplopia following coronal and translid orbital decompression in Graves' orbitopathy

    NARCIS (Netherlands)

    Paridaens, D.; Hans, K.; van Buitenen, S.; Mourits, M. P.


    PURPOSE: Firstly, to assess the incidence of induced diplopia following orbital decompression in patients with Graves' orbitopathy. Secondly, to assess patient satisfaction after orbital decompression. Thirdly, to determine the factors that contribute to the variable reported incidence of diplopia

  6. Superior vena caval obstruction - decompression with chemotherapy and subsequent irradiation

    International Nuclear Information System (INIS)

    Kolaric, K.; Maricic, Z.; Dujmovic, I.; Mrsic, Z.


    The clinical picture, pathogenesis and etiology of malignant vena caval obstruction are described. The importance of using modern methods to treat this critical condition is emphasized. Furthermore, the authors examine the principles of chemotherapeutic decompression followed by irradiation. A single dose of nitrogen mustard was applied intravenously, followed by irradiation, on 24 patients with malignant vena caval obstruction. The results of this treatment are presented. The effect of this treatment was controlled by measuring the venous blood pressure and with chest X-rays. The authors conclude, that this method of decompression is successful in the palliative treatment of this syndrom. (orig.) [de

  7. Eruptive dynamics during magma decompression: a laboratory approach (United States)

    Spina, L.; Cimarelli, C.; Scheu, B.; Wadsworth, F.; Dingwell, D. B.


    A variety of eruptive styles characterizes the activity of a given volcano. Indeed, eruptive styles can range from effusive phenomena to explosive eruptions, with related implications for hazard management. Rapid changes in eruptive style can occur during an ongoing eruption. These changes are, amongst other, related to variations in the magma ascent rate, a key parameter affecting the eruptive style. Ascent rate is in turn dependent on several factors such as the pressure in the magma chamber, the physical properties of the magma and the rate at which these properties change. According to the high number of involved parameters, laboratory decompression experiments are the best way to achieve quantitative information on the interplay of each of those factors and the related impact on the eruption style, i.e. by analyzing the flow and deformation behavior of the transparent volatile-bearing analogue fluid. We carried out decompression experiments following different decompression paths and using silicone oil as an analogue for the melt, with which we can simulate a range of melt viscosity values. For a set of experiments we added rigid particles to simulate the presence of crystals in the magma. The pure liquid or suspension was mounted into a transparent autoclave and pressurized to different final pressures. Then the sample was saturated with argon for a fixed amount of time. The decompression path consists of a slow decompression from the initial pressure to the atmospheric condition. Alternatively, samples were decompressed almost instantaneously, after established steps of slow decompression. The decompression path was monitored with pressure transducers and a high-speed video camera. Image analysis of the videos gives quantitative information on the bubble distribution with respect to depth in the liquid, pressure and time of nucleation and on their characteristics and behavior during the ongoing magma ascent. Furthermore, we also monitored the evolution of

  8. Transnasal Endoscopic Optic Nerve Decompression in Post Traumatic Optic Neuropathy. (United States)

    Gupta, Devang; Gadodia, Monica


    To quantify the successful outcome in patients following optic nerve decompression in post traumatic unilateral optic neuropathy in form of improvement in visual acuity. A prospective study was carried out over a period of 5 years (January 2011 to June 2016) at civil hospital Ahmedabad. Total 20 patients were selected with optic neuropathy including patients with direct and indirect trauma to unilateral optic nerve, not responding to conservative management, leading to optic neuropathy and subsequent impairment in vision and blindness. Decompression was done via Transnasal-Ethmo-sphenoidal route and outcome was assessed in form of post-operative visual acuity improvement at 1 month, 6 months and 1 year follow up. After surgical decompression complete recovery of visual acuity was achieved in 16 (80%) patients and partial recovery in 4 (20%). Endoscopic transnasal approach is beneficial in traumatic optic neuropathy not responding to steroid therapy and can prevent permanent disability if earlier intervention is done prior to irreversible damage to the nerve. Endoscopic optic nerve surgery can decompress the traumatic and oedematous optic nerve with proper exposure of orbital apex and optic canal without any major intracranial, intraorbital and transnasal complications.

  9. Decompressive craniectomy and hydrocephalus: proposal of a therapeutic flow chart. (United States)

    Peraio, Simone; Calcagni, Maria Lucia; Mattoli, Maria Vittoria; Marziali, Giammaria; DE Bonis, Pasquale; Pompucci, Angelo; Anile, Carmelo; Mangiola, Annunziato


    Decompressive craniectomy (DC) may be necessary to save the lives of patients suffering from intracranial hypertension. However, this procedure is not complication-free. Its two main complications are hydrocephalus and the sinking skin-flap syndrome (SSFS). The radiological findings and the clinical evaluation may be not enough to decide when and/or how to treat hydrocephalus in a decompressed patient. SSFS and hydrocephalus may be not unrelated. In fact, a patient affected by hydrocephalus, after the ventriculo-peritoneal shunt, can develop SSFS; on the other hand, SSFS per se can cause hydrocephalus. Treating hydrocephalus in decompressed patients can be challenging. Radiological findings and clinical evaluation may not be enough to define the most appropriate therapeutic strategy. Cerebrospinal fluid (CSF) dynamics and metabolic evaluations can represent important diagnostic tools for assessing the need of a CSF shunt in patients with a poor baseline neurologic status. Based on our experience, we propose a flow chart for treating decompressed patients affected by ventriculomegaly.

  10. Health care worker decompression sickness: incidence, risk and mitigation. (United States)

    Clarke, Richard


    Inadvertent exposure to radiation, chemical agents and biological factors are well recognized hazards associated with the health care delivery system. Less well appreciated yet no less harmful is risk of decompression sickness in those who accompany patients as inside attendants (IAs) during provision of hyperbaric oxygen therapy. Unlike the above hazards where avoidance is practiced, IA exposure to decompression sickness risk is unavoidable. While overall incidence is low, when calculated as number of cases over number of exposures or potential for a case during any given exposure, employee cumulative risk, defined here as number of cases over number of IAs, or risk that an IA may suffer a case, is not. Commonly, this unique occupational environmental injury responds favorably to therapeutic recompression and a period of recuperation. There are, however, permanent and career-ending consequences, and at least two nurses have succumbed to their decompression insults. The intent of this paper is to heighten awareness of hyperbaric attendant decompression sickness. It will serve as a review of reported cases and reconcile incidence against largely ignored individual worker risk. Mitigation strategies are summarized and an approach to more precisely identify risk factors that might prompt development of consensus screening standards is proposed. Copyright© Undersea and Hyperbaric Medical Society.

  11. Time-variant coherence between heart rate variability and EEG activity in epileptic patients: an advanced coupling analysis between physiological networks

    International Nuclear Information System (INIS)

    Piper, D; Schiecke, K; Pester, B; Witte, H; Benninger, F; Feucht, M


    Time-variant coherence analysis between the heart rate variability (HRV) and the channel-related envelopes of adaptively selected EEG components was used as an indicator for the occurrence of (correlative) couplings between the central autonomic network (CAN) and the epileptic network before, during and after epileptic seizures. Two groups of patients were investigated, a group with left and a group with right hemispheric temporal lobe epilepsy. The individual EEG components were extracted by a signal-adaptive approach, the multivariate empirical mode decomposition, and the envelopes of each resulting intrinsic mode function (IMF) were computed by using Hilbert transform. Two IMFs, whose envelopes were strongly correlated with the HRV’s low-frequency oscillation (HRV-LF; ≈0.1 Hz) before and after the seizure were identified. The frequency ranges of these IMFs correspond to the EEG delta-band. The time-variant coherence was statistically quantified and tensor decomposition of the time-frequency coherence maps was applied to explore the topography-time-frequency characteristics of the coherence analysis. Results allow the hypothesis that couplings between the CAN, which controls the cardiovascular-cardiorespiratory system, and the ‘epileptic neural network’ exist. Additionally, our results confirm the hypothesis of a right hemispheric lateralization of sympathetic cardiac control of the HRV-LF. (paper)

  12. Interference Cancellation Using Replica Signal for HTRCI-MIMO/OFDM in Time-Variant Large Delay Spread Longer Than Guard Interval

    Directory of Open Access Journals (Sweden)

    Yuta Ida


    Full Text Available Orthogonal frequency division multiplexing (OFDM and multiple-input multiple-output (MIMO are generally known as the effective techniques for high data rate services. In MIMO/OFDM systems, the channel estimation (CE is very important to obtain an accurate channel state information (CSI. However, since the orthogonal pilot-based CE requires the large number of pilot symbols, the total transmission rate is degraded. To mitigate this problem, a high time resolution carrier interferometry (HTRCI for MIMO/OFDM has been proposed. In wireless communication systems, if the maximum delay spread is longer than the guard interval (GI, the system performance is significantly degraded due to the intersymbol interference (ISI and intercarrier interference (ICI. However, the conventional HTRCI-MIMO/OFDM does not consider the case with the time-variant large delay spread longer than the GI. In this paper, we propose the ISI and ICI compensation methods for a HTRCI-MIMO/OFDM in the time-variant large delay spread longer than the GI.

  13. Original endoscopic orbital decompression of lateral wall through hairline approach for Graves’ ophthalmopathy: an innovation of balanced orbital decompression

    Directory of Open Access Journals (Sweden)

    Gong Y


    Full Text Available Yi Gong,1,* Jiayang Yin,2,* Boding Tong,2 Jingkun Li,3 Jiexi Zeng,2 Zhongkun Zuo,1 Fei Ye,1 Yongheng Luo,4 Jing Xiao,1 Wei Xiong2 1Department of Minimal Invasive Surgery, The Second Xiangya Hospital, Central South University, Changsha, China; 2Department of Ophthalmology and Eye Research Center, The Second Xiangya Hospital, Central South University, Changsha, China; 3E.N.T Department, The Second Xiangya Hospital, Central South University, Changsha, China; 4Department of Radiology, The Second Xiangya Hospital, Central South University, Changsha, China *These authors contributed equally to this work Background: Orbital decompression is an important surgical procedure for treatment of Graves’ ophthalmopathy (GO, especially in women. It is reasonable for balanced orbital decompression of the lateral and medial wall. Various surgical approaches, including endoscopic transnasal surgery for medial wall and eye-side skin incision surgery for lateral wall, are being used nowadays, but many of them lack the validity, safety, or cosmetic effect. Patients and methods: Endoscopic orbital decompression of lateral wall through hairline approach and decompression of medial wall via endoscopic transnasal surgery was done to achieve a balanced orbital decompression, aiming to improve the appearance of proptosis and create conditions for possible strabismus and eyelid surgery afterward. From January 29, 2016 to February 14, 2017, this surgery was performed on 41 orbits in 38 patients with GO, all of which were at inactive stage of disease. Just before surgery and at least 3 months after surgery, Hertel’s ophthalmostatometer and computed tomography (CT were used to check proptosis and questionnaires of GO quality of life (QOL were completed. Findings: The postoperative retroversion of eyeball was 4.18±1.11 mm (Hertel’s ophthalmostatometer and 4.17±1.14 mm (CT method. The patients’ QOL was significantly improved, especially the change in appearance without

  14. Dynamics of gas bubble growth in oil-refrigerant mixtures under isothermal decompression

    Energy Technology Data Exchange (ETDEWEB)

    Dias, Joao Paulo; Barbosa Junior, Jader R.; Prata, Alvaro T. [Federal University of Santa Catarina (UFSC), Florianopolis, SC (Brazil). Dept. of Mechanical Engineering], Emails:,,


    This paper proposes a numerical model to predict the growth of gaseous refrigerant bubbles in oil-refrigerant mixtures with high contents of oil subjected to isothermal decompression. The model considers an Elementary Cell (EC) in which a spherical bubble is surrounded by a concentric and spherical liquid layer containing a limited amount of dissolved liquid refrigerant. The pressure reduction in the EC generates a concentration gradient at the bubble interface and the refrigerant is transported to the bubble by molecular diffusion. After a sufficiently long period of time, the concentration gradient in the liquid layer and the bubble internal pressure reach equilibrium and the bubble stops growing, having attained its stable radius. The equations of momentum and chemical species conservation for the liquid layer, and the mass balance at the bubble interface are solved via a coupled finite difference procedure to determine the bubble internal pressure, the refrigerant radial concentration distribution and the bubble growth rate. Numerical results obtained for a mixture of ISO VG10 ester oil and refrigerant HFC-134a showed that bubble growth dynamics depends on model parameters like the initial bubble radius, initial refrigerant concentration in the liquid layer, decompression rate and EC temperature. Despite its simplicity, the model showed to be a potential tool to predict bubble growth and foaming which may result from important phenomena occurring inside refrigeration compressors such as lubrication of sliding parts and refrigerant degassing from the oil stored in oil sump during compressor start-up. (author)

  15. The effect of core decompression on local expression of BMP-2, PPAR-γ and bone regeneration in the steroid-induced femoral head osteonecrosis

    Directory of Open Access Journals (Sweden)

    Wang Wei


    Full Text Available Abstract Background To investigate the efficacy of the sole core decompression surgery for the treatment of steroid-induced femoral head osteonecrosis. Methods The model was established by administration of steroids in combination with horse serum. The rabbits with bilateral femoral head osteonecrosis were randomly selected to do the one side of core decompression. The other side was used as the sham. Quantitative RT-PCR and western blot techniques were used to measure the local expression of BMP-2 and PPAR-γ. Bone tissues from control and operation groups were histologically analyzed by H&E staining. The comparisons of the local expression of BMP-2 and PPAR-γ and the bone regeneration were further analyzed between different groups at each time point. Results The expression of BMP-2 in the osteonecrosis femoral head with or without decompression was significantly lower than that in normal animals. BMP-2 expression both showed the decreasing trend with the increased post-operation time. No significant difference of BMP-2 expression occurred between femoral head osteonecrosis with and without decompression. The PPAR-γ expression in the femoral head osteonecrosis with and without core decompression both was significantly higher than that in control. Its expression pattern showed a significantly increased trend with increased the post-operation time. However, there was no significant difference of PPAR-γ expression between the femoral head osteonecrosis with and without decompression at each time point. Histopathological analysis revealed that new trabecular bone and a large number of osteoblasts were observed in the steroid-induced femoral head osteonecrosis with lateral decompression at 8 weeks after surgery, but there still existed trabecular bone fractures and bone necrosis. Conclusions Although decompression takes partial effect in promoting bone regeneration in the early treatment of femoral head osteonecrosis, such an effect does not

  16. Decompression Sickness during Construction of the Dartford Tunnel (United States)

    Golding, F. Campbell; Griffiths, P.; Hempleman, H. V.; Paton, W. D. M.; Walder, D. N.


    A clinical, radiological and statistical survey has been made of decompression sickness during the construction of the Dartford Tunnel. Over a period of two years, 1,200 men were employed on eight-hour shifts at pressures up to 28 pounds per square inch (p.s.i.). There were 689 cases of decompression sickness out of 122,000 compressions, an incidence of 0·56%. The majority of cases (94·9%) were simple “bends”. The remainder (5·1%) exhibited signs and symptoms other than pain and were more serious. All cases were successfully treated and no fatality or permanent disability occurred. In two serious cases, cysts in the lungs were discovered. It is suggested that these gave rise to air embolism when the subjects were decompressed, and pulmonary changes may contribute more than hitherto believed to the pathogenesis of bends. Some other clinical features are described, including “skin-mottling” and an association between bends and the site of an injury. The bends rate is higher for the back shift (3 p.m. to 11 p.m.) and the night shift (11 p.m. to 7 a.m.) than for the day shift. In the treatment of decompression sickness it appears to be more satisfactory to use the minimum pressure required for relief of symptoms followed by slow decompression with occasional “soaks”, than to attempt to drive the causative bubbles into solution with high pressures. During the contract the decompression tables recently prescribed by the Ministry of Labour were used. Evidence was obtained that they could be made safer, and that the two main assumptions on which they are based (that sickness will not occur at pressures below 18 p.s.i., and that a man saturates in four hours) may be incorrect. It is desirable to test tables based on 15 p.s.i. and eight-hour saturation. The existence of acclimatization to pressure was confirmed; it is such that the bends rate may fall in two to three weeks to 0·1% of the incidence on the first day of exposure. Acclimatization is lost again

  17. Dynamics of upper mantle rocks decompression melting above hot spots under continental plates (United States)

    Perepechko, Yury; Sorokin, Konstantin; Sharapov, Victor


    temperature (THS) > 1900oC asthenolens size ~700 km. When THS = of 2000oC the maximum melting degree of the primitive mantle is near 40%. An increase in the TB > 1900oC the maximum degree of melting could rich 100% with the same size of decompression melting zone (700 km). We examined decompression melting above the HS having LHS = 100 km - 780 km at a TB 1850- 2100oC with the thickness of lithosphere = 100 km.It is shown that asthenolens size (Lln) does not change substantially: Lln=700 km at LHS = of 100 km; Lln= 800 km at LHS = of 780 km. In presence of asymmetry of large HS the region of advection is developed above the HS maximum with the formation of asymmetrical cell. Influence of lithospheric plate thicknesses on appearance and evolution of asthenolens above the HS were investigated for the model stepped profile for the TB ≤ of 1750oS with Lhs = 100km and maximum of THS =2350oC. With an increase of TB the Lln difference beneath lithospheric steps is leveled with retention of a certain difference to melting degrees and time of the melting appearance a top of the HS. RFBR grant 12-05-00625.

  18. Natural gas decompression energy recovery: Energy savings potential in Italy

    International Nuclear Information System (INIS)

    Piatti, A.; Piemonte, C.; Rampini, E.; Vatrano, F.; Techint SpA, Milan; ENEA, Rome


    This paper surveyed the natural gas distribution systems employed in the Italian civil, industrial and thermoelectric sectors to identify those installations which can make use of gas decompression energy recovery systems (consisting of turbo-expanders or alternative expanders) to economically generate electric power. Estimates were then made of the total amount of potential energy savings. The study considered as eligible for energy savings interventions only those plants with a greater than 5,000 standard cubic meter per hour plant capacity. It was evaluated that, with suitable decompression equipment installed at 50 key installations (33 civil, 15 industrial), about 200 GWh of power could be produced annually, representing potential savings of about 22,000 petroleum equivalent tonnes of energy. A comparative analysis was done on three investment alternatives involving inputs of varying amounts of Government financial assistance

  19. Decompression syndrome (Caisson disease) in an Indian diver. (United States)

    Phatak, Uday A; David, Eric J; Kulkarni, Pravin M


    Acute decompression syndrome (Caisson's disease) is an acute neurological emergency in divers. It is caused due to release of nitrogen gas bubbles that impinge the blood vessels of the spinal cord and brain and result in severe neurodeficit. There are very few case reports in Indian literature. There are multiple factors in the pathogenesis of Acute decompression syndrome (Caisson's disease) such as health problems in divers (respiratory problems or congenital heart diseases like atrial septal defect, patent ductus arteriosus etc), speed of ascent from the depth and habits like smoking that render divers susceptible for such neurological emergency. Usually, immediate diagnosis of such a condition with MRI is not possible in hospitals in the Coastal border. Even though, MRI is performed, it has very low specificity and sensitivity. Facilities like hyperbaric oxygen treatment are virtually non-existent in these hospitals. Therefore, proper education of the divers and appropriate preventive measures in professional or recreational divers is recommended.

  20. [Orbital decompression in Grave's disease: comparison of techniques]. (United States)

    Sellari-Franceschini, S; Berrettini, S; Forli, F; Bartalena, L; Marcocci, C; Tanda, M L; Nardi, M; Lepri, A; Pinchera, A


    Grave's ophthalmopathy is an inflammatory, autoimmune disorder often associated with Grave's disease. The inflammatory infiltration involves the retrobulbar fatty tissue and the extrinsic eye muscles, causing proptosis, extraocular muscle dysfunction and often diplopia. Orbital decompression is an effective treatment in such cases, particularly when resistant to drugs and external radiation therapy. This work compares the results of orbital decompression performed by removing: a) the medial and lateral walls (Mourits technique) in 10 patients (19 orbits) and b) the medial and lower walls (Walsh-Ogura technique) in 17 patients (31 orbits). The results show that removing the floor of the orbit enables better reduction of proptosis but more easily leads to post-operative diplopia. Thus it proves necessary to combine the two techniques, modifying the surgical approach on a case-by-case basis.

  1. Design of mulitlevel OLF approach ("V"-shaped decompressive laminoplasty) based on 3D printing technology. (United States)

    Ling, Qinjie; He, Erxing; Ouyang, Hanbin; Guo, Jing; Yin, Zhixun; Huang, Wenhua


    To introduce a new surgical approach to the multilevel ossification of the ligamentum flavum (OLF) aided by three-dimensional (3D) printing technology. A multilevel OLF patient (male, 66 years) was scanned using computed tomography (CT). His saved DICOM format data were inputted to the Mimics14.0 3D reconstruction software (Materialise, Belgium). The resulting 3D model was used to observe the anatomical features of the multilevel OLF area and to design the surgical approach. At the base of the spinous process, two channels were created using an osteotomy bilaterally to create a "V" shape to remove the bone ligamentous complex (BLC). The decompressive laminoplasty using mini-plate fixation was simulated with the computer. The physical model was manufactured using 3D printing technology. The patient was subsequently treated using the designed surgery. The operation was completed successfully without any complications. The operative time was 90 min, and blood loss was 200 ml. One month after the operation, neurologic function was recovered well, and the JOA score was improved from 6 preoperatively to 10. Postoperative CT scanning showed that the OLF was totally removed, and the replanted BLC had not subsided. 3D printing technology is an effective, reliable, and minimally invasive method to design operations. The technique can be an option for multilevel OLF surgical treatment. This can provide sufficient decompression with minimum damage to the spine and other intact anatomical structures.

  2. Immediate pain relief by microvascular decompression for idiopathic trigeminal neuralagia

    International Nuclear Information System (INIS)

    Haq, N.U.; Ali, M.; Khan, H.M.; Ishaq, M.; Khattak, M.I.


    Background: Trigeminal neuralgia is a common entity which is managed by neurosurgeons in day to day practice. Up-till now many treatment options have been adopted for it but micro-vascular decompression is much impressive in terms of pain control and recurrence rate in all of them. The objective of study was known the efficacy of micro vascular decompression for idiopathic trigeminal neuralgia by using muscle patch in terms of immediate pain relief. Methods: This descriptive study was carried out in Neurosurgery Department lady reading hospital, Peshawar from January 2010 to December 2012. All patients who underwent micro vascular decompression for idiopathic trigeminal neuralgia were included in the study. Patients were assessed 72 hours after the surgery by borrow neurological institute pain scale (BNIP scale) for pain relief and findings were documented on predesigned proforma. Data was analysed by SPSS-17. Results: Total 52 patients were included in this study. Among these 32 (61.53 percentage) were female and 20 (38.46 percentage) were males having age from 22-76 years (mean 49 years). Right side was involved in 36 (69.23 percentage) and left side in 16 (30.76 percentage) patients. Duration of symptoms ranged from 6 months to 16 years (mean 8 years). History of dental extraction and peripheral neurectomy was present in 20 (38 percentage) and 3(5.76 percentage) patients while V3 was most commonly involved branch with 28(57.69 percentage) frequency and combined V2,V3 involvement was 1 (11.53 percentage). Superior cerebellar artery was most common offending vessel in 46(88.46 percentage) while arachnoid adhesions were in 2(3.84 percentage) patients. We assessed patient immediate postoperatively using BNIP pain scale. Conclusion: Micro-vascular decompression is most effective mode of treatment for trigeminal neuralgia in terms of immediate pain relief. (author)

  3. On-the-Fly Decompression and Rendering of Multiresolution Terrain

    Energy Technology Data Exchange (ETDEWEB)

    Lindstrom, P; Cohen, J D


    We present a streaming geometry compression codec for multiresolution, uniformly-gridded, triangular terrain patches that supports very fast decompression. Our method is based on linear prediction and residual coding for lossless compression of the full-resolution data. As simplified patches on coarser levels in the hierarchy already incur some data loss, we optionally allow further quantization for more lossy compression. The quantization levels are adaptive on a per-patch basis, while still permitting seamless, adaptive tessellations of the terrain. Our geometry compression on such a hierarchy achieves compression ratios of 3:1 to 12:1. Our scheme is not only suitable for fast decompression on the CPU, but also for parallel decoding on the GPU with peak throughput over 2 billion triangles per second. Each terrain patch is independently decompressed on the fly from a variable-rate bitstream by a GPU geometry program with no branches or conditionals. Thus we can store the geometry compressed on the GPU, reducing storage and bandwidth requirements throughout the system. In our rendering approach, only compressed bitstreams and the decoded height values in the view-dependent 'cut' are explicitly stored on the GPU. Normal vectors are computed in a streaming fashion, and remaining geometry and texture coordinates, as well as mesh connectivity, are shared and re-used for all patches. We demonstrate and evaluate our algorithms on a small prototype system in which all compressed geometry fits in the GPU memory and decompression occurs on the fly every rendering frame without any cache maintenance.

  4. Nerve Decompression and Restless Legs Syndrome: A Retrospective Analysis

    Directory of Open Access Journals (Sweden)

    James C. Anderson


    Full Text Available IntroductionRestless legs syndrome (RLS is a prevalent sleep disorder affecting quality of life and is often comorbid with other neurological diseases, including peripheral neuropathy. The mechanisms related to RLS symptoms remain unclear, and treatment options are often aimed at symptom relief rather than etiology. RLS may present in distinct phenotypes often described as “primary” vs. “secondary” RLS. Secondary RLS is often associated with peripheral neuropathy. Nerve decompression surgery of the common and superficial fibular nerves is used to treat peripheral neuropathy. Anecdotally, surgeons sometimes report improved RLS symptoms following nerve decompression for peripheral neuropathy. The purpose of this retrospective analysis was to quantify the change in symptoms commonly associated with RLS using visual analog scales (VAS.MethodsForty-two patients completed VAS scales (0–10 for pain, burning, numbness, tingling, weakness, balance, tightness, aching, pulling, cramping, twitchy/jumpy, uneasy, creepy/crawly, and throbbing, both before and 15 weeks after surgical decompression.ResultsSubjects reported significant improvement among all VAS categories, except for “pulling” (P = 0.14. The change in VAS following surgery was negatively correlated with the pre-surgery VAS for both the summed VAS (r = −0.58, P < 0.001 and the individual VAS scores (all P < 0.01, such that patients who reported the worst symptoms before surgery exhibited relatively greater reductions in symptoms after surgery.ConclusionThis is the first study to suggest improvement in RLS symptoms following surgical decompression of the common and superficial fibular nerves. Further investigation is needed to quantify improvement using RLS-specific metrics and sleep quality assessments.

  5. Outcomes of decompressive craniectomy in patients after traumatic brain injury. (United States)

    Nambiar, Mithun; MacIsaac, Christopher; Grabinski, Rafal; Liew, Danny; Kavar, Bhadrakant


    Traumatic brain injury (TBI) can result in cerebral oedema and vascular changes resulting in an increase in intracranial pressure (ICP), which can lead to further secondary damage. Decompressive craniectomy (DC) is a surgical option in the management of ICP. We aimed to investigate outcomes of DC after TBI. We performed a retrospective audit of 57 adult patients (aged > 15 years) who underwent DC after TBI, at the Royal Melbourne Hospital from 1 January 2005 to 30 June 2011. Our functional outcome measure was the Extended Glasgow Outcome Scale (GOSE). Patients had a median age of 30 years (range, 17- 73 years). The hospital mortality rate was 47% (27 patients). A higher postoperative median ICP was the most significant predictor of hospital mortality (OR, 1.1; 95% CI, 1-1.3). There was a mean decrease of 7.7mmHg in ICP between the mean preoperative and postoperative ICP values (95% CI, - 10.5 to - 5.0mmHg). There was a mean decrease of 3.5mmHg in the mean cerebral perfusion pressure (CPP) from preoperative to postoperative CPP values (95% CI, - 6.2 to - 0.8mmHg). At the 6-month follow-up, a poor outcome (GOSE score, 1-4) was seen in 39 patients (68%), while a good outcome (GOSE score, 5- 8) was noted in 15 patients (26%). A high APACHE II score on admission was the most significant predictor of a worse GOSE score at 6 months (OR, 1.3; 95% CI, 1.1-1.5). Analysis of the APACHE II and IMPACT scores as models for predicting mortality at 6 months showed an area under the curve (AUC) of 0.792 and 0.805, respectively, and for predicting poor outcome at 6 months, showed an AUC of 0.862 and 0.883, respectively. DC decreased ICP postoperatively. The IMPACT and APACHE II scores are good models for prediction of death and poor outcome at 6 months.

  6. Experimental Evidence of Low Density Liquid Water under Decompression (United States)

    Shen, G.; Lin, C.; Sinogeikin, S. V.; Smith, J.


    Water is not only the most important substance for life, but also plays important roles in liquid science for its anomalous properties. It has been widely accepted that water's anomalies are not a result of simple thermal fluctuation, but are connected to the formation of various structural aggregates in the hydrogen bonding network. Among several proposed scenarios, one model of fluctuations between two different liquids has gradually gained traction. These two liquids are referred to as a low-density liquid (LDL) and a high-density liquid (HDL) with a coexistence line in the deeply supercooled regime at elevated pressure. The LDL-HDL transition ends with decreasing pressure at a liquid-liquid critical point (LLCP) with its Widom line extending to low pressures. Above the Widom line lies mostly HDL which is favored by entropy, while LDL, mostly lying below the Widom line, is favored by enthalpy in the tetrahedral hydrogen bonding network. The origin of water's anomalies can then be explained by the increase in structural fluctuations, as water is cooled down to deeply supercooled temperatures approaching the Widom line. Because both the LLCP and the LDL-HDL transition line lie in water's "no man's land" between the homogeneous nucleation temperature (TH, 232 K) and the crystallization temperature (TX, 150 K), the success of experiments exploring this region has been limited thus far. Using a rapid decompression technique integrated with in situ x-ray diffraction, we observe that a high-pressure ice phase transforms to a low-density noncrystalline (LDN) form upon rapid release of pressure at temperatures of 140-165K. The LDN subsequently crystallizes into ice-Ic through a diffusion-controlled process. The change in crystallization rate with temperature indicates that the LDN is a LDL with its tetrahedrally-coordinated network fully developed and clearly linked to low-density amorphous ices. The observation of the tetrahedral LDL supports the two-liquid model for

  7. Decryption-decompression of AES protected ZIP files on GPUs (United States)

    Duong, Tan Nhat; Pham, Phong Hong; Nguyen, Duc Huu; Nguyen, Thuy Thanh; Le, Hung Duc


    AES is a strong encryption system, so decryption-decompression of AES encrypted ZIP files requires very large computing power and techniques of reducing the password space. This makes implementations of techniques on common computing system not practical. In [1], we reduced the original very large password search space to a much smaller one which surely containing the correct password. Based on reduced set of passwords, in this paper, we parallel decryption, decompression and plain text recognition for encrypted ZIP files by using CUDA computing technology on graphics cards GeForce GTX295 of NVIDIA, to find out the correct password. The experimental results have shown that the speed of decrypting, decompressing, recognizing plain text and finding out the original password increases about from 45 to 180 times (depends on the number of GPUs) compared to sequential execution on the Intel Core 2 Quad Q8400 2.66 GHz. These results have demonstrated the potential applicability of GPUs in this cryptanalysis field.

  8. [Microvascular decompression for hemifacial spasm. Ten years of experience]. (United States)

    Revuelta-Gutiérrez, Rogelio; Vales-Hidalgo, Lourdes Olivia; Arvizu-Saldaña, Emiliano; Hinojosa-González, Ramón; Reyes-Moreno, Ignacio


    Hemifacial spasm characterized by involuntary paroxistic contractions of the face is more frequent on left side and in females. Evolution is progressive and in a few cases may disappear. Management includes medical treatment, botulinum toxin, and microvascular decompression of the nerve. We present the results of 116 microvascular decompressions performed in 88 patients over 10 years. All patients had previous medical treatment. All patients were operated on with microsurgical technique by asterional craniotomy. Vascular compression was present in all cases with one exception. Follow-up was from 1 month to 133 months. Were achieved excellent results in 70.45% of cases after first operation, good results in 9.09%, and poor results in 20.45% of patients. Long-term results were excellent in 81.82%, good in 6.82%, and poor in 11.36% of patients. Hypoacusia and transitory facial palsy were the main complications. Hemifacial spasm is a painless but disabling entity. Medical treatment is effective in a limited fashion. Injection of botulinum toxin has good response but benefit is transitory. Microvascular decompression is treatment of choice because it is minimally invasive, not destructive, requires minimum technical support, and yields best long-term results.

  9. Interspinous Process Decompression: Expanding Treatment Options for Lumbar Spinal Stenosis

    Directory of Open Access Journals (Sweden)

    Pierce D. Nunley


    Full Text Available Interspinous process decompression is a minimally invasive implantation procedure employing a stand-alone interspinous spacer that functions as an extension blocker to prevent compression of neural elements without direct surgical removal of tissue adjacent to the nerves. The Superion® spacer is the only FDA approved stand-alone device available in the US. It is also the only spacer approved by the CMS to be implanted in an ambulatory surgery center. We computed the within-group effect sizes from the Superion IDE trial and compared them to results extrapolated from two randomized trials of decompressive laminectomy. For the ODI, effect sizes were all very large (>1.0 for Superion and laminectomy at 2, 3, and 4 years. For ZCQ, the 2-year Superion symptom severity (1.26 and physical function (1.29 domains were very large; laminectomy effect sizes were very large (1.07 for symptom severity and large for physical function (0.80. Current projections indicate a marked increase in the number of patients with spinal stenosis. Consequently, there remains a keen interest in minimally invasive treatment options that delay or obviate the need for invasive surgical procedures, such as decompressive laminectomy or fusion. Stand-alone interspinous spacers may fill a currently unmet treatment gap in the continuum of care and help to reduce the burden of this chronic degenerative condition on the health care system.

  10. Farris-Tang retractor in optic nerve sheath decompression surgery. (United States)

    Spiegel, Jennifer A; Sokol, Jason A; Whittaker, Thomas J; Bernard, Benjamin; Farris, Bradley K


    Our purpose is to introduce the use of the Farris-Tang retractor in optic nerve sheath decompression surgery. The procedure of optic nerve sheath fenestration was reviewed at our tertiary care teaching hospital, including the use of the Farris-Tang retractor. Pseudotumor cerebri is a syndrome of increased intracranial pressure without a clear cause. Surgical treatment can be effective in cases in which medical therapy has failed and disc swelling with visual field loss progresses. Optic nerve sheath decompression surgery (ONDS) involves cutting slits or windows in the optic nerve sheath to allow cerebrospinal fluid to escape, reducing the pressure around the optic nerve. We introduce the Farris-Tang retractor, a retractor that allows for excellent visualization of the optic nerve sheath during this surgery, facilitating the fenestration of the sheath and visualization of the subsequent cerebrospinal fluid egress. Utilizing a medial conjunctival approach, the Farris-Tang retractor allows for easy retraction of the medial orbital tissue and reduces the incidence of orbital fat protrusion through Tenon's capsule. The Farris-Tang retractor allows safe, easy, and effective access to the optic nerve with good visualization in optic nerve sheath decompression surgery. This, in turn, allows for greater surgical efficiency and positive patient outcomes.

  11. Rapid decompression and desorption induced energetic failure in coal

    Directory of Open Access Journals (Sweden)

    Shugang Wang


    Full Text Available In this study, laboratory experiments are conducted to investigate the rapid decompression and desorption induced energetic failure in coal using a shock tube apparatus. Coal specimens are recovered from Colorado at a depth of 610 m. The coal specimens are saturated with the strong sorbing gas CO2 for a certain period and then the rupture disc is suddenly broken on top of the shock tube to generate a shock wave propagating upwards and a rarefaction wave propagating downwards through the specimen. This rapid decompression and desorption has the potential to cause energetic fragmentation in coal. Three types of behaviors in coal after rapid decompression are found, i.e. degassing without fragmentation, horizontal fragmentation, and vertical fragmentation. We speculate that the characteristics of fracture network (e.g. aperture, spacing, orientation and stiffness and gas desorption play a role in this dynamic event as coal can be considered as a dual porosity, dual permeability, dual stiffness sorbing medium. This study has important implications in understanding energetic failure process in underground coal mines such as coal gas outbursts.

  12. Protective effects of fluoxetine on decompression sickness in mice.

    Directory of Open Access Journals (Sweden)

    Jean-Eric Blatteau

    Full Text Available Massive bubble formation after diving can lead to decompression sickness (DCS that can result in central nervous system disorders or even death. Bubbles alter the vascular endothelium and activate blood cells and inflammatory pathways, leading to a systemic pathophysiological process that promotes ischemic damage. Fluoxetine, a well-known antidepressant, is recognized as having anti-inflammatory properties at the systemic level, as well as in the setting of cerebral ischemia. We report a beneficial clinical effect associated with fluoxetine in experimental DCS. 91 mice were subjected to a simulated dive at 90 msw for 45 min before rapid decompression. The experimental group received 50 mg/kg of fluoxetine 18 hours before hyperbaric exposure (n = 46 while controls were not treated (n = 45. Clinical assessment took place over a period of 30 min after surfacing. At the end, blood samples were collected for blood cells counts and cytokine IL-6 detection. There were significantly fewer manifestations of DCS in the fluoxetine group than in the controls (43.5% versus 75.5%, respectively; p = 0.004. Survivors showed a better and significant neurological recovery with fluoxetine. Platelets and red cells were significantly decreased after decompression in controls but not in the treated mice. Fluoxetine reduced circulating IL-6, a relevant marker of systemic inflammation in DCS. We concluded that fluoxetine decreased the incidence of DCS and improved motor recovery, by limiting inflammation processes.

  13. Decompression of the facial nerve in cases of hemifacial spasm

    Directory of Open Access Journals (Sweden)

    Karsten Kettel


    Full Text Available Among 11 patients a complete cure was obtained in one case, a fair result in 4 cases, while in 6 cases the effect of the operation has only been temporary and full recurrence has taken place. Even if decompression has thus resulted in a few recoveries and improvements, the results in the majority of cases have been disappointing. Everything points to hemifacial spasm being due to a disorder of the lower motor neuron. Intracranial lesions in the vicinity of the facial nerve are known to have resulted in irritation and spasm. It may be perfectly true that the majority of cases of hemifacial spasm are due to a lesion, the nature of which may vary, in the Fallopian canal near the stylomastoid foramen, not least the postparalytic following Bell's palsy. But the disappointing results of decompression seems to indicate that at the time of operation irreparable damage to the nerve has in the majority of cases been already done. Consequently I gave up decompression in cases of hemifacial spasm some years ago. Good results from injections of alcohol into the nerve have been reported13 but I prefer selective sections of the branches to the muscles involved as described by German and Greenwood8.

  14. Anterior cervical decompression and fusion with caspar plate fixation

    International Nuclear Information System (INIS)

    Rehman, L.; Akbar, H.; Das, G.; Hashim, A.S.M.


    Objective: To evaluate the role of anterior cervical decompression and fixation with Caspar plating in cervical spine injury on neurological outcome. Study Design: A case series. Place and Duration of Study: Department of Neurosurgery, Jinnah Postgraduate Medical Centre, Karachi, from July 2008 to March 2011. Methodology: Thirty patients admitted with cervical spine injuries were inducted in the study. All cases were evaluated for their clinical features, level of injury and degree of neurological injury was assessed using Frankel grading. Pre and postoperative record with X-rays and MRI were maintained. Cervical traction was applied to patients with sub-luxation. All patients underwent anterior cervical decompression, fusion and Caspar plate fixation. The follow-up period was 6 months with clinical and radiological assessment. Results: Among 30 patients, 24 (80%) were males and 6 (20%) were females. Age ranged from 15 to 55 years. Causes of injury were road traffic accident (n = 20), fall (n = 8) and assault (n = 2). Commonest mode of injury was road traffic accident (66.6%). Postoperative follow-up showed that pain and neurological deficit were improved in 21 patients. There was no improvement in 7 patients, one patient deteriorated and one expired. All patients developed pain at donor site. Conclusion: Anterior decompression, fusion and fixation with Caspar plate is an effective method with good neurological and radiological outcome. However, it is associated with pain at donor site. (author)

  15. Contribution to the study of heat transfer coefficients during the decompression of a water cooled heating tube

    International Nuclear Information System (INIS)

    Bonneton, Michel.


    The main correlations likely to be suitable for describing heat transfers between the fluid and wall during decompression are analyzed. The most important experimental work on the boiling crisis in the transient regime is presented. Experimental studies are then treated. The test installation (OMEGA experiment), the instumentation used and the experiments realized are described. The purpose of these experiments was to establish heat exchange laws for decompression conditions. Local and instantaneous exchange coefficients were determined in a heated test section together with the thermohydraulic parameters of the flow. The methods used to investigate the measurements made and to analyze their validity are described. Finally, the test results are presented and discussed. It is shown that under certain conditions, the boiling crisis can be determined with a permanent regime correlation. An attempt is made to establish a correlation for the transition boiling zone from these results. A test reconstitution calculation based on a two-fluid model is presented [fr

  16. Fluoxetine protection in decompression sickness in mice is enhanced by blocking TREK-1 potassium channel with the spadin antidepressant.

    Directory of Open Access Journals (Sweden)

    Nicolas eVallée


    Full Text Available In mice, disseminated coagulation, inflammation and ischemia induce neurological damages that can lead to the death. These symptoms result from circulating bubbles generated by a pathogenic decompression. An acute fluoxetine treatment or the presence of the TREK-1 potassium channel increased the survival rate when mice are subjected to an experimental dive/decompression protocol. This is a paradox because fluoxetine is a blocker of TREK-1 channels. First, we studied the effects of an acute dose of fluoxetine (50mg/kg in wild-type (WT and TREK-1 deficient mice (Knockout homozygous KO and heterozygous HET. Then, we combined the same fluoxetine treatment with a five-day treatment by spadin, in order to specifically block TREK-1 activity (KO-like mice. KO and KO-like mice could be regarded as antidepressed models.167 mice (45 WTcont 46 WTflux 30 HETflux and 46 KOflux constituting the flux-pool and 113 supplementary mice (27 KO-like 24 WTflux2 24 KO-likeflux 21 WTcont2 17 WTno dive constituting the spad-pool were included in this study. Only 7% of KO-TREK-1 treated with fluoxetine (KOflux and 4% of mice treated with both spadin and fluoxetine (KO-likeflux died from decompression sickness (DCS symptoms. These values are much lower than those of WT control (62% or KO-like mice (41%. After the decompression protocol, mice showed a significant consumption of their circulating platelets and leukocytes.Spadin antidepressed mice were more likely to declare DCS. Nevertheless, which had both blocked TREK-1 channel and were treated with fluoxetine were better protected against DCS. We conclude that the protective effect of such an acute dose of fluoxetine is enhanced when TREK-1 is inhibited. We confirmed that antidepressed models may have worse DCS outcomes, but a concomitant fluoxetine treatment not only decreases DCS severity but increases the survival rate.

  17. Intraoperative computed tomography for cervicomedullary decompression of foramen magnum stenosis in achondroplasia: two case reports. (United States)

    Arishima, Hidetaka; Tsunetoshi, Kenzo; Kodera, Toshiaki; Kitai, Ryuhei; Takeuchi, Hiroaki; Kikuta, Ken-Ichiro


    The authors report two cases of cervicomedullary decompression of foramen magnum (FM) stenosis in children with achondroplasia using intraoperative computed tomography (iCT). A 14-month-old girl with myelopathy and retarded motor development, and a 10-year-old girl who had already undergone incomplete FM decompression was presented with myelopathy. Both patients underwent decompressive sub-occipitalcraniectomy and C1 laminectomy without duraplasty using iCT. It clearly showed the extent of FM decompression during surgery, which finally enabled sufficient decompression. After the operation, their myelopathy improved. We think that iCT can provide useful information and guidance for sufficient decompression for FM stenosis in children with achondroplasia.

  18. Probabilistic Assessment of Hypobaric Decompression Sickness Treatment Success (United States)

    Conkin, Johnny; Abercromby, Andrew F. J.; Dervay, Joseph P.; Feiveson, Alan H.; Gernhardt, Michael L.; Norcross, Jason R.; Ploutz-Snyder, Robert; Wessel, James H., III


    The Hypobaric Decompression Sickness (DCS) Treatment Model links a decrease in computed bubble volume from increased pressure (DeltaP), increased oxygen (O2) partial pressure, and passage of time during treatment to the probability of symptom resolution [P(symptom resolution)]. The decrease in offending volume is realized in 2 stages: a) during compression via Boyle's Law and b) during subsequent dissolution of the gas phase via the O2 window. We established an empirical model for the P(symptom resolution) while accounting for multiple symptoms within subjects. The data consisted of 154 cases of hypobaric DCS symptoms along with ancillary information from tests on 56 men and 18 women. Our best estimated model is P(symptom resolution) = 1 / (1+exp(-(ln(Delta P) - 1.510 + 0.795×AMB - 0.00308×Ts) / 0.478)), where (DeltaP) is pressure difference (psid), AMB = 1 if ambulation took place during part of the altitude exposure, otherwise AMB = 0; and where Ts is the elapsed time in mins from start of the altitude exposure to recognition of a DCS symptom. To apply this model in future scenarios, values of DeltaP as inputs to the model would be calculated from the Tissue Bubble Dynamics Model based on the effective treatment pressure: (DeltaP) = P2 - P1 | = P1×V1/V2 - P1, where V1 is the computed volume of a spherical bubble in a unit volume of tissue at low pressure P1 and V2 is computed volume after a change to a higher pressure P2. If 100% ground level O2 (GLO) was breathed in place of air, then V2 continues to decrease through time at P2 at a faster rate. This calculated value of (DeltaP then represents the effective treatment pressure at any point in time. Simulation of a "pain-only" symptom at 203 min into an ambulatory extravehicular activity (EVA) at 4.3 psia on Mars resulted in a P(symptom resolution) of 0.49 (0.36 to 0.62 95% confidence intervals) on immediate return to 8.2 psia in the Multi-Mission Space Exploration Vehicle. The P(symptom resolution) increased

  19. Enduring improvement in Oswestry Disability Index outcomes following lumbar microscopic interlaminar decompression: An appraisal of prospectively collected patient outcomes. (United States)

    Khan, Muhammad Babar; Bashir, Muhammad Umair; Kumar, Rajesh; Enam, Syed Ather


    Our present study aims to assess the short and long-term postoperative outcome of microscopic interlaminar decompression from a neurosurgical center in a developing country and also aims to further determine any predictors of functional outcome. All patients with moderate to severe symptomatic stenosis undergoing elective posterior lumbar spinal decompression were prospectively enrolled in a database. Preoperative, 2 weeks and 2 years postoperative Oswestry Disability Index (ODI) scores were determined for all patients. These scores were retrospectively compared using repeated measures analysis of variance. Further, linear regression modelling was applied to determine the effect of preoperative ODI, body mass index, age, prior physiotherapy, duration of symptoms, and single or multiple level decompression on the change in ODI at 2 weeks and 2 years follow-up respectively. A total of 60 consecutive patients (40 males, 20 females) were included for statistical analysis. The percentage of patients with a minimum clinically important difference (MCID), using an ODI threshold value of 10, was 86.7% (n = 52) at the 2 weeks postoperative follow-up. At the 2 years follow-up assessment, 3.3% (n = 2) patients who had earlier not achieved MCID did so, 78.3% (n = 47) of patients were found to have a change in ODI score of <10 or no change, while 18.3% (n = 11) reported a deterioration in their ODI scores. The preoperative ODI score was an independent predictor of change in ODI score at 2 weeks and 2 years respectively (P < 0.0005). The duration of symptoms prior to surgery was found to predict the change in ODI at 2 years follow-up (P = 0.04). The evidence regarding the long-term and short-term efficacy of microscopic interlaminar decompression in symptomatic lumbar stenosis is overwhelming. Preoperative ODI scores and duration of symptoms prior to surgery can predict postoperative outcomes.

  20. Frequency of decompression illness among recent and extinct mammals and "reptiles": a review (United States)

    Carlsen, Agnete Weinreich


    The frequency of decompression illness was high among the extinct marine "reptiles" and very low among the marine mammals. Signs of decompression illness are still found among turtles but whales and seals are unaffected. In humans, the risk of decompression illness is five times increased in individuals with Patent Foramen Ovale; this condition allows blood shunting from the venous circuit to the systemic circuit. This right-left shunt is characteristic of the "reptile" heart, and it is suggested that this could contribute to the high frequency of decompression illness in the extinct reptiles.

  1. Aseptic necrosis in caisson workers: a new set of decompression tables. (United States)

    Downs, G J; Kindwall, E P


    There is a high incidence of aseptic necrosis and decompression sickness among caisson workers due to inadequate decompression using the current OSHA decompression tables (1-7). Because of this, a new set of tables--Autodec III-O2--was developed which more effectively eliminates nitrogen from the body and, therefore, should decrease the incidence of both bends and aseptic necrosis. The Autodec III-O2 schedule's superiority was statistically significant at a level of 0.08 compared to the OSHA table. It is our conclusion that OSHA should adopt the Autodec III-O2 schedule as a replacement for the current decompression tables.

  2. Trends in Orbital Decompression Techniques of Surveyed American Society of Ophthalmic Plastic and Reconstructive Surgery Members. (United States)

    Reich, Shani S; Null, Robert C; Timoney, Peter J; Sokol, Jason A

    To assess current members of the American Society of Ophthalmic Plastic and Reconstructive Surgery (ASOPRS) regarding preference in surgical techniques for orbital decompression in Graves' disease. A 10-question web-based, anonymous survey was distributed to oculoplastic surgeons utilizing the ASOPRS listserv. The questions addressed the number of years of experience performing orbital decompression surgery, preferred surgical techniques, and whether orbital decompression was performed in collaboration with an ENT surgeon. Ninety ASOPRS members participated in the study. Most that completed the survey have performed orbital decompression surgery for >15 years. The majority of responders preferred a combined approach of floor and medial wall decompression or balanced lateral and medial wall decompression; only a minority selected a technique limited to 1 wall. Those surgeons who perform fat decompression were more likely to operate in collaboration with ENT. Most surgeons rarely remove the orbital strut, citing risk of worsening diplopia or orbital dystopia except in cases of optic nerve compression or severe proptosis. The most common reason given for performing orbital decompression was exposure keratopathy. The majority of surgeons perform the surgery without ENT involvement, and number of years of experience did not correlate significantly with collaboration with ENT. The majority of surveyed ASOPRS surgeons prefer a combined wall approach over single wall approach to initial orbital decompression. Despite the technological advances made in the field of modern endoscopic surgery, no single approach has been adopted by the ASOPRS community as the gold standard.

  3. Effect of oxygen-breathing during a decompression-stop on bubble-induced platelet activation after an open-sea air dive: oxygen-stop decompression. (United States)

    Pontier, J-M; Lambrechts, K


    We highlighted a relationship between decompression-induced bubble formation and platelet micro-particle (PMP) release after a scuba air-dive. It is known that decompression protocol using oxygen-stop accelerates the washout of nitrogen loaded in tissues. The aim was to study the effect of oxygen deco-stop on bubble formation and cell-derived MP release. Healthy experienced divers performed two scuba-air dives to 30 msw for 30 min, one with an air deco-stop and a second with 100% oxygen deco-stop at 3 msw for 9 min. Bubble grades were monitored with ultrasound and converted to the Kisman integrated severity score (KISS). Blood samples for cell-derived micro-particle analysis (AnnexinV for PMP and CD31 for endothelial MP) were taken 1 h before and after each dive. Mean KISS bubble score was significantly lower after the dive with oxygen-decompression stop, compared to the dive with air-decompression stop (4.3 ± 7.3 vs. 32.7 ± 19.9, p air-breathing decompression stop, we observed an increase of the post-dive mean values of PMP (753 ± 245 vs. 381 ± 191 ng/μl, p = 0.003) but no significant change in the oxygen-stop decompression dive (329 ± 215 vs. 381 +/191 ng/μl, p = 0.2). For the post-dive mean values of endothelial MP, there was no significant difference between both the dives. The Oxygen breathing during decompression has a beneficial effect on bubble formation accelerating the washout of nitrogen loaded in tissues. Secondary oxygen-decompression stop could reduce bubble-induced platelet activation and the pro-coagulant activity of PMP release preventing the thrombotic event in the pathogenesis of decompression sickness.

  4. Posterior Fossa Decompression with Duraplasty in Chiari-1 Malformations

    International Nuclear Information System (INIS)

    Rehman, L.; Akbar, H.; Bokhari, I.; Babar, A. K.; Hahim, A. S. M.; Arain, S. H.


    Objective: To evaluate the symptomatic outcome after PFD (Posterior Fossa Decompression) with duraplasty in Chiari-1 malformations. Study Design: Case series. Place and Duration of Study: Department of Neurosurgery, JPMC, Karachi, from July 2008 to September 2012. Methodology: This included 21 patients of Chiari 1 malformations admitted in department through OPD with clinical features of headache, neck pain, numbness, neurological deficit, and syringomyelia. Diagnosis was confirmed by MRI. PFD followed by C1 laminectomy with duraplasty was done in all cases and symptomatic outcome was assessed in follow-up clinic. Results: Among 21 patients, 13 were females and 8 were males. Age ranged from 18 to 40 years. All the patients had neck pain and numbness in hands. Only 3 patients had weakness of all four limbs and 12 with weakness of hands. Symptoms evolved over a mean of 12 months. Syringomyelia was present in all cases. All patients underwent posterior fossa decompression with duraplasty with an additional C1 laminectomy and in 2 cases C2 laminectomy was done. Syringo-subarachnoid shunt was placed in one patient and ventriculo-peritoneal shunt was placed in 2 patients. Pain was relieved in all cases. Weakness was improved in all cases and numbness was improved in 19 cases. Syringomyelia was improved in all cases. Postoperative complications included CSF leak in 2 patients and wound infection in one patient. However, there was no mortality. Conclusion: Posterior fossa decompression with duraplasty is the best treatment option for Chiari-1 malformations because of symptomatic improvement and less chances of complications. (author)

  5. Decompression tables for inside chamber attendants working at altitude. (United States)

    Bell, James; Thombs, Paul A; Davison, William J; Weaver, Lindell K


    Hyperbaric oxygen (HBO2) multiplace chamber inside attendants (IAs) are at risk for decompression sickness (DCS). Standard decompression tables are formulated for sea-level use, not for use at altitude. At Presbyterian/St. Luke's Medical Center (Denver, Colorado, 5,924 feet above sea level) and Intermountain Medical Center (Murray, Utah, 4,500 feet), the decompression obligation for IAs is managed with U.S. Navy Standard Air Tables corrected for altitude, Bühlmann Tables, and the Nobendem© calculator. IAs also breathe supplemental oxygen while compressed. Presbyterian/St. Luke's (0.83 atmospheres absolute/atm abs) uses gauge pressure, uncorrected for altitude, at 45 feet of sea water (fsw) (2.2 atm abs) for routine wound care HBO2 and 66 fsw (2.8 atm abs) for carbon monoxide/cyanide poisoning. Presbyterian/St. Luke's provides oxygen breathing for the IAs at 2.2 atm abs. At Intermountain (0.86 atm abs), HBO2 is provided at 2.0 atm abs for routine treatments and 3.0 atm abs for carbon monoxide poisoning. Intermountain IAs breathe intermittent 50% nitrogen/50% oxygen at 3.0 atm abs and 100% oxygen at 2.0 atm abs. The chamber profiles include a safety stop. From 1990-2013, Presbyterian/St. Luke's had 26,900 total IA exposures: 25,991 at 45 fsw (2.2 atm abs) and 646 at 66 fsw (2.8 atm abs); there have been four cases of IA DCS. From 2008-2013, Intermountain had 1,847 IA exposures: 1,832 at 2 atm abs and 15 at 3 atm abs, with one case of IA DCS. At both facilities, DCS incidents occurred soon after the chambers were placed into service. Based on these results, chamber inside attendant risk for DCS at increased altitude is low when the inside attendants breathe supplemental oxygen.

  6. Piezosurgery for orbital decompression surgery in thyroid associated orbitopathy. (United States)

    Ponto, Katharina A; Zwiener, Isabella; Al-Nawas, Bilal; Kahaly, George J; Otto, Anna F; Karbach, Julia; Pfeiffer, Norbert; Pitz, Susanne


    The purpose of this study was to assess a piezosurgical device as a novel tool for bony orbital decompression surgery. At a multidisciplinary orbital center, 62 surgeries were performed in 40 patients with thyroid associated orbitopathy (TAO). Within this retrospective case-series, we analyzed the medical records of these consecutive unselected patients. The reduction of proptosis was the main outcome measure. Indications for a two (n = 27, 44%) or three wall (35, 56%) decompression surgery were proptosis (n = 50 orbits, 81%) and optic neuropathy (n = 12, 19%). Piezosurgery enabled precise bone cuts without intraoperative complications. Proptosis decreased from 23.6 ± 2.8 mm (SD) by 3 mm (95% CI: -3.6 to -2.5 mm) after surgery and stayed stable at 3 months (-3 mm, 95% CI: -3.61 to -2.5 mm, p 24 mm versus ≤ 24 mm: -3.4 mm versus -2.81 mm before discharge from hospital and -4.1 mm versus -2.1 mm at 3 months: p < 0.001, respectively). After a mean long-term follow-up period of 14.6 ± 10.4 months proptosis decreased by further -0.7 ± 2.0 mm (p < 0.001). Signs of optic nerve compression improved after surgery. Infraorbital hypesthesia was present in 11 of 21 (52%) orbits 3 months after surgery. The piezosurgical device is a useful tool for orbital decompression surgery in TAO. By cutting bone selectively, it is precise and reduces the invasiveness of surgery. Nevertheless, no improvement in outcome or reduction in morbidity over conventional techniques has been shown so far. Copyright © 2014 European Association for Cranio-Maxillo-Facial Surgery. Published by Elsevier Ltd. All rights reserved.

  7. SLAP repair with arthroscopic decompression of spinoglenoid cyst

    Directory of Open Access Journals (Sweden)

    Hashiguchi Hiroshi


    Full Text Available Introduction: A spinoglenoid cyst with suprascapular nerve disorders is highly associated with superior labrum anterior posterior (SLAP lesion. Conservative or surgical treatment is applied to relieve pain and neurological symptoms. The purpose of this study was to evaluate clinical outcomes of patients treated by arthroscopic surgery for SLAP lesion with a spinoglenoid cyst. Methods: The subjects of this study were six patients with SLAP lesion with a spinoglenoid cyst who underwent arthroscopic surgery. There was one female and five males with a mean age of 48.5 years. SLAP lesion was found in all the patients at arthroscopy. A small tear of the rotator cuff was found in the two patients. The SLAP lesion was repaired using suture anchors, and the rotator cuff tears were repaired by suture-bridge fixation. The spinoglenoid cyst was decompressed through the torn labrum in three patients, and through the released superior to posterior portion of the capsule in the other three patients. Results: All patients showed excellent improvement in pain and muscle strength at the final follow-up examination. The mean Constant score was improved from 60.5 points preoperatively to 97.2 points postoperatively. The mean visual analog scale (VAS score decreased from 4.5 on the day of the surgery to 2.5 within one week postoperatively. Postoperative MRI showed disappearance or reduction of the spinoglenoid cyst in four and two patients, respectively. There were no complications from the surgical intervention and in the postoperative period. Discussion: The patients treated by decompression through the released capsule obtained pain relief at an early period after the surgery. Arthroscopic treatment for a spinoglenoid cyst can provide a satisfactory clinical outcome. Arthroscopic decompression of a spinoglenoid cyst through the released capsule is recommended for a safe and reliable procedure for patients with suprascapular nerve disorders.

  8. Analysis of fatigue reliability for high temperature and high pressure multi-stage decompression control valve (United States)

    Yu, Long; Xu, Juanjuan; Zhang, Lifang; Xu, Xiaogang


    Based on stress-strength interference theory to establish the reliability mathematical model for high temperature and high pressure multi-stage decompression control valve (HMDCV), and introduced to the temperature correction coefficient for revising material fatigue limit at high temperature. Reliability of key dangerous components and fatigue sensitivity curve of each component are calculated and analyzed by the means, which are analyzed the fatigue life of control valve and combined with reliability theory of control valve model. The impact proportion of each component on the control valve system fatigue failure was obtained. The results is shown that temperature correction factor makes the theoretical calculations of reliability more accurate, prediction life expectancy of main pressure parts accords with the technical requirements, and valve body and the sleeve have obvious influence on control system reliability, the stress concentration in key part of control valve can be reduced in the design process by improving structure.

  9. Decompression illness treated in Denmark 1999-2013

    DEFF Research Database (Denmark)

    Juhl, Christian Svendsen; Hedetoft, Morten; Bidstrup, Daniel


    of previous dives, type of diving, initial type of hyperbaric treatment and DCI symptoms. Trend in annual case numbers was evaluated using run chart analysis and Spearman's correlation. Age, height, weight, and BMI were evaluated using linear regression. The presence of long-term residual symptoms......INTRODUCTION: The incidence, diver characteristics and symptomatology of decompression illness (DCI) in Denmark has not been assessed since 1982, and the presence of long-term residual symptoms among divers receiving hyperbaric oxygen therapy in Denmark has never been estimated to our knowledge...

  10. Investigation of Hematologic and Pathologic Response to Decompression. (United States)


    in tadpole and very young kangaroos . Am. J. Physiol. 120:59—74 , 1937. 12. D’ C’~~~’ B.G. and Swanson , H. Bubble free decompression of blood samples...1955. 24. Takeda , Y. Studies of the metabol i~~ 5 and distribution of fibrino— gen in healthy men with autologous I-labe led fibrinogen. J. Clin...this connective tissue protein. However , the metabolism of bone collagen is affected by hormonal control (l0; 3l) and vitamin influences (3 ;ll). It

  11. Technique of ICP monitored stepwise intracranial decompression effectively reduces postoperative complications of severe bifrontal contusion

    Directory of Open Access Journals (Sweden)

    Guan eSun


    Full Text Available Background Bifrontal contusion is a common clinical brain injury. In the early stage, it is often mild, but it progresses rapidly and frequently worsens suddenly. This condition can become life threatening and therefore requires surgery. Conventional decompression craniectomy is the commonly used treatment method. In this study, the effect of ICP monitored stepwise intracranial decompression surgery on the prognosis of patients with acute severe bifrontal contusion was investigated. Method A total of 136 patients with severe bifrontal contusion combined with deteriorated intracranial hypertension admitted from March 2001 to March 2014 in our hospital were selected and randomly divided into two groups, i.e., a conventional decompression group and an intracranial pressure (ICP monitored stepwise intracranial decompression group (68 patients each, to conduct a retrospective study. The incidence rates of acute intraoperative encephalocele, delayed hematomas, and postoperative cerebral infarctions and the Glasgow outcome scores (GOSs 6 months after the surgery were compared between the two groups.Results (1 The incidence rates of acute encephalocele and contralateral delayed epidural hematoma in the stepwise decompression surgery group were significantly lower than those in the conventional decompression group; the differences were statistically significant (P < 0.05; (2 6 months after the surgery, the incidence of vegetative state and mortality in the stepwise decompression group were significantly lower than those in the conventional decompression group (P < 0.05; the rate of favorable prognosis in the stepwise decompression group was also significantly higher than that in the conventional decompression group (P < 0.05.Conclusions The ICP monitored stepwise intracranial decompression technique reduced the perioperative complications of traumatic brain injury through the gradual release of intracranial pressure and was beneficial to the prognosis of

  12. Effect of active compression-decompression resuscitation (ACD-CPR) on survival: a combined analysis using individual patient data

    DEFF Research Database (Denmark)

    Mauer, Dietmar; Nolan, Jerry; Plaisance, Patrick


    Cardiopulmonary resuscitation, compression, decompression, cardiac arrest, emergency medical service, advanced cardiac life support, survival......Cardiopulmonary resuscitation, compression, decompression, cardiac arrest, emergency medical service, advanced cardiac life support, survival...

  13. Deep lateral wall orbital decompression following strabismus surgery in patients with Type II ophthalmic Graves' disease. (United States)

    Ellis, Michael P; Broxterman, Emily C; Hromas, Alan R; Whittaker, Thomas J; Sokol, Jason A


    Surgical management of ophthalmic Graves' disease traditionally involves, in order, orbital decompression, followed by strabismus surgery and eyelid surgery. Nunery et al. previously described two distinct sub-types of patients with ophthalmic Graves' disease; Type I patients exhibit no restrictive myopathy (no diplopia) as opposed to Type II patients who do exhibit restrictive myopathy (diplopia) and are far more likely to develop new-onset worsening diplopia following medial wall and floor decompression. Strabismus surgery involving extra-ocular muscle recession has, in turn, been shown to potentially worsen proptosis. Our experience with Type II patients who have already undergone medial wall and floor decompression and strabismus surgery found, when additional decompression is necessary, deep lateral wall decompression (DLWD) appears to have a low rate of post-operative primary-gaze diplopia. A case series of four Type II ophthalmic Graves' disease patients, all of whom had already undergone decompression and strabismus surgery, and went on to develop worsening proptosis or optic nerve compression necessitating further decompression thereafter. In all cases, patients were treated with DLWD. Institutional Review Board approval was granted by the University of Kansas. None of the four patients treated with this approach developed recurrent primary-gaze diplopia or required strabismus surgery following DLWD. While we still prefer to perform medial wall and floor decompression as the initial treatment for ophthalmic Graves' disease, for proptosis following consecutive strabismus surgery, DLWD appears to be effective with a low rate of recurrent primary-gaze diplopia.

  14. Influence of surgical decompression on the expression of inflammatory and tissue repair biomarkers in periapical cysts. (United States)

    Rodrigues, Janderson Teixeira; Dos Santos Antunes, Henrique; Armada, Luciana; Pires, Fábio Ramôa


    The biologic effects of surgical decompression on the epithelium and connective tissues of periapical cysts are not fully understood. The aim of this study was to evaluate the expression of tissue repair and inflammatory biomarkers in periapical cysts before and after surgical decompression. Nine specimens of periapical cysts treated with decompression before undergoing complete enucleation were immunohistochemically analyzed to investigate the expression of interleukin-1β, tumor necrosis factor-α, transforming growth factor-β1, matrix metalloproteinase-9, Ki-67, and epidermal growth factor receptor. Expression of the biomarkers was classified as positive, focal, or negative. Ki-67 immunoexpression was calculated as a cell proliferation index. The expression of the biomarkers was compared in the specimens from decompression and from the final surgical procedure. Computed tomography demonstrated that volume was reduced in all cysts after decompression. There were no differences in the immunoexpression of the proinflammatory and tissue repair biomarkers when comparing the specimens obtained before and after the decompression. Surgical decompression was efficient in reducing the volume of periapical cysts before complete enucleation. When comparing the specimens obtained from surgical decompression and from complete surgical removal, the immunohistochemical analysis did not show a decrease in proinflammatory biomarkers; neither did it show an increase in tissue repair biomarkers. Copyright © 2017 Elsevier Inc. All rights reserved.

  15. Tension pneumothorax secondary to automatic mechanical compression decompression device. (United States)

    Hutchings, A C; Darcy, K J; Cumberbatch, G L A


    The details are presented of the first published case of a tension pneumothorax induced by an automatic compression-decompression (ACD) device during cardiac arrest. An elderly patient collapsed with back pain and, on arrival of the crew, was in pulseless electrical activity (PEA) arrest. He was promptly intubated and correct placement of the endotracheal tube was confirmed by noting equal air entry bilaterally and the ACD device applied. On the way to the hospital he was noted to have absent breath sounds on the left without any change in the position of the endotracheal tube. Needle decompression of the left chest caused a hiss of air but the patient remained in PEA. Intercostal drain insertion in the emergency department released a large quantity of air from his left chest but without any change in his condition. Post-mortem examination revealed a ruptured abdominal aortic aneurysm as the cause of death. Multiple left rib fractures and a left lung laceration secondary to the use of the ACD device were also noted, although the pathologist felt that the tension pneumothorax had not contributed to the patient's death. It is recommended that a simple or tension pneumothorax should be considered when there is unilateral absence of breath sounds in addition to endobronchial intubation if an ACD device is being used.

  16. A metastable liquid melted from a crystalline solid under decompression (United States)

    Lin, Chuanlong; Smith, Jesse S.; Sinogeikin, Stanislav V.; Kono, Yoshio; Park, Changyong; Kenney-Benson, Curtis; Shen, Guoyin


    A metastable liquid may exist under supercooling, sustaining the liquid below the melting point such as supercooled water and silicon. It may also exist as a transient state in solid-solid transitions, as demonstrated in recent studies of colloidal particles and glass-forming metallic systems. One important question is whether a crystalline solid may directly melt into a sustainable metastable liquid. By thermal heating, a crystalline solid will always melt into a liquid above the melting point. Here we report that a high-pressure crystalline phase of bismuth can melt into a metastable liquid below the melting line through a decompression process. The decompression-induced metastable liquid can be maintained for hours in static conditions, and transform to crystalline phases when external perturbations, such as heating and cooling, are applied. It occurs in the pressure-temperature region similar to where the supercooled liquid Bi is observed. Akin to supercooled liquid, the pressure-induced metastable liquid may be more ubiquitous than we thought.

  17. Decompression syndrome (Caisson disease in an Indian diver

    Directory of Open Access Journals (Sweden)

    Phatak Uday


    Full Text Available Acute decompression syndrome (Caisson′s disease is an acute neurological emergency in divers. It is caused due to release of nitrogen gas bubbles that impinge the blood vessels of the spinal cord and brain and result in severe neurodeficit. There are very few case reports in Indian literature. There are multiple factors in the pathogenesis of Acute decompression syndrome (Caisson′s disease such as health problems in divers (respiratory problems or congenital heart diseases like atrial septal defect, patent ductus arteriosus etc, speed of ascent from the depth and habits like smoking that render divers susceptible for such neurological emergency. Usually, immediate diagnosis of such a condition with MRI is not possible in hospitals in the Coastal border. Even though, MRI is performed, it has very low specificity and sensitivity. Facilities like hyperbaric oxygen treatment are virtually non-existent in these hospitals. Therefore, proper education of the divers and appropriate preventive measures in professional or recreational divers is recommended.

  18. Endoscopic Decompression and Marsupialization of A Duodenal Duplication Cyst

    Directory of Open Access Journals (Sweden)

    Eliza I-Lin Sin


    Full Text Available Introduction: Duodenal duplication cysts are rare congenital foregut anomalies, accounting for 2%–12% of all gastrointestinal tract duplications. Surgical excision entails risk of injury to the pancreaticobiliary structures due to proximity or communication with the cyst. We present a case of duodenal duplication cyst in a 3 year-old boy who successfully underwent endoscopic decompression. Case report: AT is a young boy who first presented at 15 months of age with abdominal pain. There was one subsequent episode of pancreatitis. Ultrasonography showed the typical double wall sign of a duplication cyst and magnetic resonance cholangio-pancreatography showed a large 5 cm cyst postero-medial to the second part of the duodenum, communicating with the pancreaticobiliary system and causing dilatation of the proximal duodenum. He subsequently underwent successful endoscopic ultrasound guided decompression at 3 years of age under general anesthesia, and had an uneventful postoperative recovery. Conclusion: Endoscopic ultrasound guided assessment and treatment of gastrointestinal duplication cysts is increasingly reported in adults. To the best of our knowledge, only one case of endoscopic treatment of duodenal duplication cyst, in an older child, has been reported thus far in the paediatric literature. In this paper, we review the current literature and discuss the therapeutic options of this rare condition.

  19. Needle Decompression in Appalachia Do Obese Patients Need Longer Needles?

    Directory of Open Access Journals (Sweden)

    Carter, Thomas Edward


    Full Text Available Introduction: Needle decompression of a tension pneumothorax can be a lifesaving procedure. It requires an adequate needle length to reach the chest wall to rapidly remove air. With adult obesity exceeding one third of the United States population in 2010, we sought to evaluate the proper catheter length that may result in a successful needle decompression procedure. Advance Trauma Life Support (ATLS currently recommends a 51 millimeter (mm needle, while the needles stocked in our emergency department are 46 mm. Given the obesity rates of our patient population, we hypothesize these needles would not have a tolerable success rate of 90%. Methods: We retrospectively reviewed 91 patient records that had computed tomography of the chest and measured the chest wall depth at the second intercostal space bilaterally. Results: We found that 46 mm needles would only be successful in 52.7% of our patient population, yet the ATLS recommended length of 51 mm has a success rate of 64.8%. Therefore, using a 64 mm needle would be successful in 79% percent of our patient population. Conclusion: Use of longer length needles for needle thoracostomy is essential given the extent of the nation’s adult obesity population. [West J Emerg Med. 2013;14(6:650-652.

  20. Laser Disc Decompression In Emam Khomeini Hospital 1996-1999

    Directory of Open Access Journals (Sweden)

    Ghaffar Poor. M


    Full Text Available Low back pain is among the most frequent medical complaints and a major public health problem. 1.7 percent of cases are caused by herniated disc, 20 percent of which require interventional treatment. Percutaneous laser disc decompression (P.L.DD can be considered as an effective therapeutic alternative in certain cases."nMaterials and Methods: To determine the efficacy of this method in Iran in patient's with low back pain due to disc herniation, 40 patients according to medical history, physical examination and MRI findings were selected for this study. Patients who had canal stenosis, marginal, osteophyte, advanced disc dehydration, ruptured posterior ligament and other contraindication were excluded. CT scan was used only for needle navigation. After proper positioning of needle, nucleous pulposus was evapourated with Nd-YAG laser. Total energy was 1200-1600j. The procedure was done out patient and follow up has been done at 1 day, 1 week, 1,3, 6 and 12 months."nResults: There was no serious complication. 80 percent of patients in one-year follow up showed significant clinical improvement."nConclusion: Our findings suggests that percutaneous laser disc decompression can be considered as an effective alternative method of treatment for disc herniation and patient selection is the critical factor which determines success rate.

  1. Effect of decompression drying treatment on physical properties of solid foods. (United States)

    Morikawa, Takuya; Takada, Norihisa; Miura, Makoto


    This study used a decompression drying instrument to investigate the effects of a drying treatment on the physical properties of solid foods. Commercial tofu was used as a model food and was treated at different temperature and pressure conditions in a drying chamber. Overall, high temperatures resulted in better drying. Additionally, pressure in the chamber influenced the drying conditions of samples. Differences in physical properties, such as food texture, shrinkage, and color were observed among some samples, even with similar moisture content. This was caused by differences in moisture distribution in the food, which seems to have manifested as a thin, dried film on the surfaces of samples. It caused inefficient drying and changes in physical properties. Control of the drying conditions (i.e. pressure and heat supply) has relations with not only physical properties, but also the drying efficiency of solid foods.

  2. Transferability of decompression wave speed measured by a small-diameter shock tube to full size pipelines and implications for determining required fracture propagation resistance

    International Nuclear Information System (INIS)

    Botros, K.K.; Geerligs, J.; Rothwell, Brian; Carlson, Lorne; Fletcher, Leigh; Venton, Philip


    The control of propagating ductile (or tearing) fracture is a fundamental requirement in the fracture control design of pipelines. The Battelle two-curve method developed in the early 1970s still forms the basis of the analytical framework used throughout the industry. GASDECOM is typically used for calculating decompression speed, and idealizes the decompression process as isentropic and one-dimensional, taking no account of frictional effects. While this approximation appears not to have been a major issue for large-diameter pipes and for moderate pressures (up to 12 MPa), there have been several recent full-scale burst tests at higher pressures and smaller diameters for which the measured decompression velocity has deviated progressively from the predicted values, in general towards lower velocities. The present research was focused on determining whether pipe diameter was a major factor that could limit the applicability of frictionless models such as GASDECOM. Since potential diameter effects are primarily related to wall friction, which in turn is related to the ratio of surface roughness-to-diameter, an experimental approach was developed based on keeping the diameter constant, at a sufficiently small value to allow for an economical experimental arrangement, and varying the internal roughness. A series of tests covering a range of nominal initial pressures from 10 to 21 MPa, and involving a very lean gas and three progressively richer compositions, were conducted using two specialized high-pressure shock tubes (42 m long, I.D. = 38.1 mm). The first is honed to an extremely smooth surface finish, in order to minimize frictional effects and better simulate the behaviour of larger-diameter pipelines, while the second has a higher internal surface roughness. The results show that decompression wave speeds in the rough tube are consistently slower than those in the smooth tube under the same conditions of mixture composition and initial pressure and temperature

  3. Effectiveness of early decompressive surgery for massive hemispheric embolic infarction

    International Nuclear Information System (INIS)

    Osada, Hideo; Mori, Kentaro; Yamamoto, Takuji; Nakao, Yasuaki; Oyama, Kazutaka; Esaki, Takanori; Watanabe, Mitsuya


    Massive hemispheric embolic infarction associated with acute brain swelling and rapid clinical deterioration is known as malignant infarction because of the significant rates of mortality and morbidity. Decompressive hemicraniectomy is effective; however, the timing and outcome still remain unclear. Ninety-four patients with massive embolic hemispheric infarctions (infarct volume >200 ml) were retrospectively divided into 3 groups: 29 patients, treated conservatively (conservative group); 33 patients, operated on after the appearance of signs of brain herniation (late surgery group); and 32 patients, operated on before the onset of signs of brain herniation signs (early surgery group). The mortality at 1 and 6 months in the late surgery group (15.2% and 24.2%, respectively) was significantly improved as compared to the conservative group (62.1% and 69.0%, respectively) (p 200 ml) should be performed before the onset of brain herniation. Early surgery may achieve a satisfactory functional recovery. (author)

  4. The potential role of perfluorocarbon emulsions in decompression illness. (United States)

    Spiess, Bruce D


    Decompression illness (DCI) is an occasional occurrence in sport, professional, and military diving as well as a potential catastrophe in high-altitude flight, space exploration, mining, and caisson bridge construction. DCI theoretically could be a success-limiting problem in escape from a disabled submarine (DISSUB). Perfluorocarbon emulsions (PFCs) have previously been investigated as 'blood substitutes' with one approved by the United States Food and Drug Administration for the treatment of myocardial ischaemia. PFCs possess enhanced (as compared to plasma) respiratory gas solubility characteristics, including oxygen, nitrogen and carbon dioxide. This review examines approximately 30 years of research regarding the utilization of PFCs in gas embolism as well as experimental DCI. To date, no humans have been treated with PFCs for DCI.

  5. Compressed air tunneling and caisson work decompression procedures: development, problems, and solutions. (United States)

    Kindwall, E P


    Multinational experience over many years indicates that all current air decompression schedules for caisson and compressed air tunnel workers are inadequate. All of them, including the Occupational Safety and Health Administration tables, produce dysbaric osteonecrosis. The problem is compounded because decompression sickness (DCS) tends to be underreported. Permanent damage in the form of central nervous system or brain damage may occur in compressed air tunnel workers, as seen on magnetic resonance imaging, in addition to dysbaric osteonecrosis. Oxygen decompression seems to be the only viable method for safely decompressing tunnel workers. Oxygen decompression of tunnel workers has been successfully used in Germany, France, and Brazil. In Germany, only oxygen decompression of compressed air workers is permitted. In our experience, U.S. Navy tables 5 and 6 usually prove adequate to treat DCS in caisson workers despite extremely long exposure times, allowing patients to return to work following treatment for DCS. Tables based on empirical data and not on mathematical formulas seem to be reasonably safe. U.S. Navy Exceptional Exposure Air Decompression tables are compared with caisson tables from the United States and Great Britain.

  6. 2014 Decompression Sickness/Extravehicular Activity Risks Standing Review Panel (United States)

    Steinberg, Susan; Mahon, Richard; Klaus, David; Neuman, Tom; Pilmanis, Andrew; Regis, David


    The 2014 Decompression Sickness (DCS)/Extravehicular Activity (EVA) Risks Standing Review Panel (from here on referred to as the SRP) met for a site visit in Houston, TX on November 4 - 5, 2014. The SRP reviewed the Research Plans for The Risk of Decompression Sickness and the Risk of Injury and Compromised Performance due to EVA Operations, as well as the Evidence Reports for both of these Risks. The SRP found that the NASA DCS/EVA team did an excellent job of presenting their research plans. The SRP considers it critical that NASA proceeds with the high priority tasks identified in this report (DCS1, DCS3, DCS5). The highest priority is to determine the acceptable DCS and hypoxia risk associated with the planned human exploration beyond low Earth orbit. The risk of DCS is highly dependent upon the pressure within the exploration vehicle. If slightly more hypoxia is permitted then (even with the same percentage of oxygen) the pressure within the exploration vehicle can be lowered thus further mitigating the risk of DCS. The second highest priority is to test and validate the recommended 8.2psi/34% O2 atmosphere. Development of procedures and equipment for human exploration missions are very limited until the results of this testing are completed. The SRP also suggests that DCS7 be separated into two Gaps. Gap DCS7 should deal with DCS treatment while a new Gap should be created to deal with the long-term effects of DCS. The SRP also encourages NASA to increase collaboration with other organizations and pool resources where possible. The current NASA DCS/EVA team has the extensive expertise and a wealth of knowledge in this area. The SRP suggests that increased manpower for this team would be highly productive.

  7. The Mars Project: Avoiding Decompression Sickness on a Distant Planet (United States)

    Conkin, Johnny


    A cost-effective approach for Mars exploration is to use available resources, such as water and atmospheric gases. Nitrogen (N2) and argon (Ar) are available and could form the inert gas component of a habitat atmosphere at 8.0, 9.0, or 10.0 pounds per square inch (psia). The habitat and space suit are designed as an integrated system: a comfortable living environment about 85% of the time and a safe working environment about 15% of the time. A goal is to provide a system that permits unrestricted exploration of Mars, but the risk of decompression sickness (DCS) during the extravehicular activity in a 3.75-psia suit, after exposure to any of the three habitat conditions, may limit unrestricted exploration. I evaluate here the risk of DCS since a significant proportion of a trinary breathing gas in the habitat might contain Ar. I draw on past experience and published information to extrapolate into untested, multivariable conditions to evaluate risk. A rigorous assessment of risk as a probability of DCS for each habitat condition is not yet possible. Based on many assumptions about Ar in hypobaric decompressions, I conclude that the presence of Ar significantly increases the risk of DCS. The risk is significant even with the best habitat option: 2.56 psia oxygen, 3.41 psia N2, and 2.20 psia Ar. Several hours of prebreathing 100% 02, a higher suit pressure, or a combination of other important variables such as limited exposure time on the surface or exercise during prebreathe would be necessary to reduce the risk of DCS to an acceptable level. The acceptable level for DCS risk on Mars has not yet been determined. Mars is a great distance from Earth and therefore from primary medical care. The acceptable risk would necessarily be defined by the capability to treat DCS in the Rover vehicle, in the habitat, or both.

  8. Unusual Clinical Presentation and Role of Decompressive Craniectomy in Herpes Simplex Encephalitis. (United States)

    Singhi, Pratibha; Saini, Arushi Gahlot; Sahu, Jitendra Kumar; Kumar, Nuthan; Vyas, Sameer; Vasishta, Rakesh Kumar; Aggarwal, Ashish


    Decompressive craniectomy in pediatric central nervous infections with refractory intracranial hypertension is less commonly practiced. We describe improved outcome of decompressive craniectomy in a 7-year-old boy with severe herpes simplex encephalitis and medically refractory intracranial hypertension, along with a brief review of the literature. Timely recognition of refractory intracranial hypertension and surgical decompression in children with herpes simplex encephalitis can be life-saving. Additionally, strokelike atypical presentations are being increasingly recognized in children with herpes simplex encephalitis and should not take one away from the underlying herpes simplex encephalitis. © The Author(s) 2014.

  9. Evaluation on therapeutic effect of de-compressive craniectomies for patients with diffuse brain swelling

    International Nuclear Information System (INIS)

    Xiao Sanchao; Zhang Changrong; Zuo Yi; Zhou Xiaowei; Li Jian


    Objective: To evaluate the therapeutic effect of de-compressive craniectomies in acute traumatic patients with diffuse brain swelling. Methods: 23 patients with acute posttraumatic diffuse brain swelling admitted and confirmed by X-CT were randomly treated by surgical de-compressive craniectomies (operative group). Their treated results were compared with those of another 11 patients treated conservatively (non-operative group) at the same period. Results: The mortality rate was similar in both operative and nonoperative groups. Conclusion: The de-compressive craniectomy operation has no value and not valid for treatment of acute posttraumatic diffuse brain swelling

  10. Quantification of submarine groundwater discharge and its short-term dynamics by linking time-variant end-member mixing analysis and isotope mass balancing (222-Rn) (United States)

    Petermann, Eric; Knöller, Kay; Stollberg, Reiner; Scholten, Jan; Rocha, Carlos; Weiß, Holger; Schubert, Michael


    Submarine groundwater discharge (SGD) plays a crucial role for the water quality of coastal waters due to associated fluxes of nutrients, organic compounds and/or heavy-metals. Thus, the quantification of SGD is essential for evaluating the vulnerability of coastal water bodies with regard to groundwater pollution as well as for understanding the matter cycles of the connected water bodies. Here, we present a scientific approach for quantifying discharge of fresh groundwater (GWf) and recirculated seawater (SWrec), including its short-term temporal dynamics, into the tide-affected Knysna estuary, South Africa. For a time-variant end-member mixing analysis we conducted time-series observations of radon (222Rn) and salinity within the estuary over two tidal cycles in combination with estimates of the related end-members for seawater, river water, GWf and SWrec. The mixing analysis was treated as constrained optimization problem for finding an end-member mixing ratio that simultaneously fits the observed data for radon and salinity best for every time-step. Uncertainty of each mixing ratio was quantified by Monte Carlo simulations of the optimization procedure considering uncertainty in end-member characterization. Results reveal the highest GWf and SWrec fraction in the estuary during peak low tide with averages of 0.8 % and 1.4 %, respectively. Further, we calculated a radon mass balance that revealed a daily radon flux of 4.8 * 108 Bq into the estuary equivalent to a GWf discharge of 29.000 m3/d (9.000-59.000 m3/d for 25th-75th percentile range) and a SWrec discharge of 80.000 m3/d (45.000-130.000 m3/d for 25th-75th percentile range). The uncertainty of SGD reflects the end-member uncertainty, i.e. the spatial heterogeneity of groundwater composition. The presented approach allows the calculation of mixing ratios of multiple uncertain end-members for time-series measurements of multiple parameters. Linking these results with a tracer mass balance allows conversion

  11. Effect of metabolic gases and water vapor, perfluorocarbon emulsions, and nitric oxide on tissue bubbles during decompression sickness. (United States)

    Randsøe, Thomas


    In aviation and diving, fast decrease in ambient pressure, such as during accidental loss of cabin pressure or when a diver decompresses too fast to sea level, may cause nitrogen (N2) bubble formation in blood and tissue resulting in decompression sickness (DCS). Conventional treatment of DCS is oxygen (O2) breathing combined with recompression.  However, bubble kinetic models suggest, that metabolic gases, i.e. O2 and carbon dioxide (CO2), and water vapor contribute significantly to DCS bubble volume and growth at hypobaric altitude exposures. Further, perfluorocarbon emulsions (PFC) and nitric oxide (NO) donors have, on an experimental basis, demonstrated therapeutic properties both as treatment and prophylactic intervention against DCS. The effect was ascribed to solubility of respiratory gases in PFC, plausible NO elicited nuclei demise and/or N2 washout through enhanced blood flow rate. Accordingly, by means of monitoring injected bubbles in exposed adipose tissue or measurements of spinal evoked potentials (SEPs) in anaesthetized rats, the aim of this study was to: 1) evaluate the contribution of metabolic gases and water vapor to bubble volume at different barometrical altitude exposures, 2) clarify the O2 contribution and N2 solubility from bubbles during administration of PFC at normo- and hypobaric conditions and, 3) test the effect of different NO donors on SEPs during DCS upon a hyperbaric air dive and, to study the influence of  NO on tissue bubbles at high altitude exposures. The results support the bubble kinetic models and indicate that metabolic gases and water vapor contribute significantly to bubble volume at 25 kPa (~10,376 m above sea level) and constitute a threshold for bubble stabilization or decay at the interval of 47-36 kPa (~6,036 and ~7,920 m above sea level). The effect of the metabolic gases and water vapor seemed to compromise the therapeutic properties of both PFC and NO at altitude, while PFC significantly increased bubble

  12. Magmatic storage conditions, decompression rate, and incipient caldera collapse of the 1902 eruption of Santa Maria Volcano, Guatemala (United States)

    Andrews, Benjamin J.


    Phase equilibria experiments and analysis of natural pumice and phenocryst compositions indicate the 1902 Santa Maria dacite was stored at ~ 140-170 MPa and 840-850 °C prior to eruption. H2O-saturated, cold-seal experiments conducted in vessels with an intrinsic log fO2 of NNO + 1 ± 0.5 show that the natural phase assemblage (melt + plagioclase + amphibole + orthopyroxene + Fe-Ti oxides + apatite) is stable from approximately 115-140 MPa at temperatures below ~ 825 °C, to ~ 840-860 °C at 150 MPa, to > 850 and Ridolfi et al., 2010) applied to experimental samples suggest two populations of amphiboles, phenocrysts grown during the experiments and inherited xenocrysts, but the pressure-temperature conditions returned by the geothermobarometer are routinely > 50 MPa and > 50 °C greater than experimental run conditions; precise estimates of magmatic conditions based solely upon amphibole composition are likely inaccurate. The experimental results and analysis of natural crystals suggest that although the natural amphiboles likely record a broad range of magmatic conditions, only the lower bounds of that range reflect pre-eruptive storage conditions. Comparison of Santa Maria microlite abundances with decompression experiments examining other silicic systems from the literature suggests that the 1902 dacite decompressed at the rate of ~ 0.005 to 0.01 MPa/s during the eruption. Applying the decompression rate with the previously described eruption rate of approximately 2-3 × 108 kg/s (Williams and Self, 1983; Carey and Sparks, 1986) to the conduit model CONFLOW reveals that the eruption conduit was dike-like with an along-strike length > 1 km. Despite depositing ~ 20 km3 of dacite tephra (equivalent to ~ 8.5 km3 magma), the 1902 eruption did not form an obvious caldera. This work suggests that collapse of the dike-like conduit terminated the eruption, preventing full caldera collapse.

  13. Different effect of l-NAME treatment on susceptibility to decompression sickness in male and female rats. (United States)

    Mazur, Aleksandra; Buzzacott, Peter; Lambrechts, Kate; Wang, Qiong; Belhomme, Marc; Theron, Michael; Popov, Georgi; Distefano, Giovanni; Guerrero, Francois


    Vascular bubble formation results from supersaturation during inadequate decompression contributes to endothelial injuries, which form the basis for the development of decompression sickness (DCS). Risk factors for DCS include increased age, weight-fat mass, decreased maximal oxygen uptake, chronic diseases, dehydration, and nitric oxide (NO) bioavailability. Production of NO is often affected by diving and its expression-activity varies between the genders. Little is known about the influence of sex on the risk of DCS. To study this relationship we used an animal model of Nω-nitro-l-arginine methyl ester (l-NAME) to induce decreased NO production. Male and female rats with diverse ages and weights were divided into 2 groups: treated with l-NAME (in tap water; 0.05 mg·mL(-1) for 7 days) and a control group. To control the distribution of nitrogen among tissues, 2 different compression-decompression protocols were used. Results showed that l-NAME was significantly associated with increased DCS in female rats (p = 0.039) only. Weight was significant for both sexes (p = 0.01). The protocol with the highest estimated tissue pressures in the slower compartments was 2.6 times more likely to produce DCS than the protocol with the highest estimated tissue pressures in faster compartments. The outcome of this study had significantly different susceptibility to DCS after l-NAME treatment between the sexes, while l-NAME per se had no effect on the likelihood of DCS. The analysis also showed that for the appearance of DCS, the most significant factors were type of protocol and weight.

  14. Decompressive craniectomy in aneurysmal subarachnoid haemorrhage for hematoma or oedema versus secondary infarction

    NARCIS (Netherlands)

    Goedemans, Taco; Verbaan, Dagmar; Coert, Bert A.; Sprengers, Marieke E. S.; van den Berg, René; Vandertop, W. Peter; van den Munckhof, Pepijn


    Decompressive craniectomy (DC) has been proposed as lifesaving treatment in aneurysmal subarachnoid haemorrhage (aSAH) patients with elevated intracranial pressure (ICP). However, data is sparse and controversy exists whether the underlying cause of elevated ICP influences neurological outcome. The

  15. Human Decompression Trial With 1.3 ATA Oxygen in Helium

    National Research Council Canada - National Science Library


    The Naval Medical Research Institute (NMRI) was tasked to develop helium-oxygen decompression tables for a proposed closed circuit breathing apparatus which Will deliver a constant oxygen partial pressure of 1.3 atmospheres (ATA...


    Directory of Open Access Journals (Sweden)

    V. Ya. Medvedev


    Full Text Available The article presents results of petrophysical laboratory experiments in studies of decompression phenomena associated with consequences of abrupt displacements in fault zones. Decompression was studied in cases of controlled pressure drop that caused sharp changes of porosity and permeability parameters, and impacts of such decompression were analyzed. Healing of fractured-porous medium by newly formed phases was studied. After experiments with decompression, healing of fractures and pores in silicate rock samples (3×2×2 cm, 500 °C, 100 MPa took about 800–1000 hours, and strength of such rocks was restored to 0.6–0.7 of the original value. In nature, fracture healing is influenced by a variety of factors, such as size of discontinuities in rock masses, pressure and temperature conditions, pressure drop gradients, rock composition and saturation with fluid. Impacts of such factors are reviewed.

  17. Interspinous process device versus standard conventional surgical decompression for lumbar spinal stenosis: Randomized controlled trial

    NARCIS (Netherlands)

    W.A. Moojen (Wouter); M.P. Arts (Mark); W.C.H. Jacobs (Wilco); E.W. van Zwet (Erik); M.E. van den Akker-van Marle (Elske); B.W. Koes (Bart); C.L.A.M. Vleggeert-Lankamp (Carmen); W.C. Peul (Wilco)


    markdownabstractAbstract Objective To assess whether interspinous process device implantation is more effective in the short term than conventional surgical decompression for patients with intermittent neurogenic claudication due to lumbar spinal stenosis. Design Randomized controlled

  18. Transconjunctival orbital decompression in Graves' ophthalmopathy: lateral wall approach ab interno

    NARCIS (Netherlands)

    A.D.A. Paridaens (Dion); K. Verhoeff; D. Bouwens; W.A. van den Bosch (Willem)


    textabstractAIMS: A modified surgical technique is described to perform a one, two, or three wall orbital decompression in patients with Graves' ophthalmopathy. METHODS: The lateral wall was approached ab interno through a "swinging eyelid" approach (lateral canthotomy

  19. Early versus late orbital decompression in Graves' orbitopathy: a retrospective study in 125 patients

    NARCIS (Netherlands)

    Baldeschi, Lelio; Wakelkamp, Iris M. M. J.; Lindeboom, Robert; Prummel, Marc F.; Wiersinga, Wilmar M.


    PURPOSE: To determine if early rehabilitative orbital decompression in Graves' orbitopathy (GO) leads to a more effective postoperative outcome than the same intervention performed at a later, more likely, fibrotic stage. DESIGN: Retrospective comparative case series. PARTICIPANTS: The medical

  20. Oxygen breathing accelerates decompression from saturation at 40 msw in 70-kg swine. (United States)

    Petersen, Kyle; Soutiere, Shawn E; Tucker, Kathryn E; Dainer, Hugh M; Mahon, Richard T


    Submarine disaster survivors can be transferred from a disabled submarine at a pressure of 40 meters of seawater (msw) to a new rescue vehicle; however, they face an inherently risky surface interval before recompression and an enormous decompression obligation due to a high likelihood of saturation. The goal was to design a safe decompression protocol using oxygen breathing and a trial-and-error methodology. We hypothesized that depth, timing, and duration of oxygen breathing during decompression from saturation play a role to mitigate decompression outcomes. Yorkshire swine (67-75 kg), compressed to 40 msw for 22 h, underwent one of three accelerated decompression profiles: (1) 13.3 h staged air decompression to 18 msw, followed by 1 h oxygen breathing, then dropout; (2) direct decompression to 18 msw followed by 1 h oxygen breathing then dropout; and (3) 1 h oxygen prebreathe at 40 msw followed by 1 h mixed gas breathing at 26 msw, 1 h oxygen breathing at 18 msw, and 1 h ascent breathing oxygen. Animals underwent 2-h observation for signs of DCS. Profile 1 (14.3 h total) resulted in no deaths, no Type II DCS, and 20% Type I DCS. Profile 2 (2.1 h total) resulted in 13% death, 50% Type II DCS, and 75% Type I DCS. Profile 3 (4.5 h total) resulted in 14% death, 21% Type II DCS, and 57% Type I DCS. No oxygen associated seizures occurred. Profile 1 performed best, shortening decompression with no death or severe DCS, yet it may still exceed emergency operational utility in an actual submarine rescue.

  1. Alternative technique in atypical spinal decompression: the use of the ultrasonic scalpel in paediatric achondroplasia (United States)

    Woodacre, Timothy; Sewell, Matthew; Clarke, Andrew J; Hutton, Mike


    Spinal stenosis can be a very disabling condition. Surgical decompression carries a risk of dural tear and neural injury, which is increased in patients with severe stenosis or an atypical anatomy. We present an unusual case of symptomatic stenosis secondary to achondroplasia presenting in a paediatric patient, and highlight a new surgical technique used to minimise the risk of dural and neural injury during decompression. PMID:27288205

  2. Bilateral Ocular Decompression Retinopathy after Ahmed Valve Implantation for Uveitic Glaucoma

    Directory of Open Access Journals (Sweden)

    Javier Flores-Preciado


    Full Text Available Case Report: We report the case of a 29-year-old man who underwent Ahmed valve implantation in both eyes as treatment for uveitic glaucoma, subsequently presenting with bilateral ocular decompression retinopathy in the postoperative period. Discussion: Ocular decompression retinopathy is a rare complication of filtering surgery in patients with glaucoma; however, the course is benign in most cases, with spontaneous resolution of bleedings and improvement of visual acuity.

  3. Left Atrial Decompression by Percutaneous Left Atrial Venting Cannula Insertion during Venoarterial Extracorporeal Membrane Oxygenation Support

    Directory of Open Access Journals (Sweden)

    Ha Eun Kim


    Full Text Available Patients with venoarterial extracorporeal membrane oxygenation (ECMO frequently suffer from pulmonary edema due to left ventricular dysfunction that accompanies left heart dilatation, which is caused by left atrial hypertension. The problem can be resolved by left atrium (LA decompression. We performed a successful percutaneous LA decompression with an atrial septostomy and placement of an LA venting cannula in a 38-month-old child treated with venoarterial ECMO for acute myocarditis.

  4. Needle Decompression of Tension Pneumothorax Tactical Combat Casualty Care Guideline Recommendations (United States)


    suspected torso trauma , consider a tension pneumothorax and decompress the chest on the side of the injury with a 14-gauge, 3.25 inch (8cm) needle...and known or suspected torso trauma , consider a tension pneumothorax and decompress the chest on the side of the injury with a 14-gauge, 3.25 inch...these studies used civilian volunteers, retrospective trauma database analysis and cadavers to measure the mean chest wall thickness. This population

  5. Exploiting Aerobic Fitness to Reduce Risk of Hypobaric Decompression Sickness (United States)

    Conkin, J.; Gernhardt, M. L.; Wessel, J. H.


    Decompression sickness (DCS) is multivariable. But we hypothesize an aerobically fit person is less likely to experience hypobaric DCS than an unfit person given that fitness is exploited as part of the denitrogenation (prebreathe, PB) process prior to an altitude exposure. Aerobic fitness is peak oxygen uptake (VO2pk, ml/kg/min). Treadmill or cycle protocols were used over 15 years to determine VO2pks. We evaluated dichotomous DCS outcome and venous gas emboli (VGE) outcome detected in the pulmonary artery with Doppler ultrasound associated with VO2pk for two classes of experiments: 1) those with no PB or PB under resting conditions prior to ascent in an altitude chamber, and 2) PB that included exercise for some part of the PB. There were 165 exposures (mean VO2pk 40.5 plus or minus 7.6 SD) with 25 cases of DCS in the first protocol class and 172 exposures (mean VO2pk 41.4 plus or minus 7.2 SD) with 25 cases of DCS in the second. Similar incidence of the DCS (15.2% vs. 14.5%) and VGE (45.5% vs. 44.8%) between the two classes indicates that decompression stress was similar. The strength of association between outcome and VO2pk was evaluated using univariate logistic regression. An inverse relationship between the DCS outcome and VO2pk was evident, but the relationship was strongest when exercise was done as part of the PB (exercise PB, coef. = -0.058, p = 0.07; rest or no PB, coef. = -0.005, p = 0.86). There was no relationship between VGE outcome and VO2pk (exercise PB, coef. = -0.003, p = 0.89; rest or no PB, coef. = 0.014, p = 0.50). A significant change in probability of DCS was associated with fitness only when exercise was included in the denitrogenation process. We believe a fit person that exercises during PB efficiently eliminates dissolved nitrogen from tissues.

  6. A traumatic central cord syndrome occurring after adequate decompression for cervical spondylosis: biomechanics of injury: case report. (United States)

    Dickerman, Rob D; Lefkowitz, Michael; Epstein, Joseph A


    Case report with review of the literature. To present the first case of a central cord syndrome occurring after adequate decompression, and review the mechanics of the cervical spinal cord injury and postoperative biomechanical and anatomic changes occurring after cervical decompressive laminectomy. Cervical spondylosis is a common pathoanatomic occurrence in the elderly population and is thought to be one of the primary causes for a central cord syndrome. Decompressive laminectomy with or without fusion has been a primary treatment for spondylotic disease and is thought to be protective against further injury. To our knowledge, there are no cases of a central cord syndrome occurring after adequate decompression reported in the literature. Case study with extensive review of the literature. The patient underwent C3-C7 cervical laminectomy without complications. After surgery, the patient's spasticity and gait difficulties improved. She was discharged to inpatient rehabilitation for further treatment of upper extremity weakness. The patient fell in the rehabilitation center, with a central cord syndrome despite adequate decompression of her spinal canal. The patient was treated conservatively for the central cord and had minimal improvement. Decompressive laminectomy provides an immediate decompressive effect on the spinal cord as seen by the dorsal migration of the cord, however, the biomechanics of the cervical spine after decompressive laminectomy remain uncertain. This case supports the ongoing research and need for more intensive research on postoperative cervical spine biomechanics, including decompressive laminectomies, decompressive laminectomy and fusion, and laminoplasty.

  7. Evaluation of decompression tables by Doppler technique in caisson work in The Netherlands. (United States)

    Breedijk, J H; Van der Putten, G J G M; Schrier, L M; Sterk, W


    Hyperbaric work was conducted for constructing an underground tramway in the Netherlands. A total of 11,647 exposures were conducted in 41,957 hours. For these working conditions specifically developed oxygen decompression tables were used. Fifteen workers were submitted to Doppler monitoring after caisson work at a depth at 12 msw. Measurements were done according to the Canadian DCIEM protocol. For bubble grading the Kisman-Masurel 12-points ordinal scale (0-IV) was used. Bubbles were detected in 17 of the 38 examinations. The highest grade (III-) was found in four measurements. At rest the grading was never higher than I+. Two hours after decompression the grading was remarkably higher than after one hour. Bubble scores were relatively low, although the maximum grading probably is not reached within two hours after decompression. It may be concluded that the oxygen decompression tables used, were reliable under these heavy working conditions. At group level, decompression stress can be evaluated by Doppler monitoring. In order to reduce health hazard of employees, use of oxygen during decompression in caisson work should be embodied in the occupational standard.

  8. Decompression of keratocystic odontogenic tumors leading to increased fibrosis, but without any change in epithelial proliferation. (United States)

    Awni, Sarah; Conn, Brendan


    The aim of this study was to investigate whether decompression treatment induces changes in the histology or biologic behavior of keratocystic odontogenic tumor (KCOT). Seventeen patients with KCOT underwent decompression treatment with or without enucleation. Histologic evaluation and immunohistochemical expression of p53, Ki-67, and Bcl-2 were analyzed by using conventional microscopy. KCOT showed significantly increased fibrosis (P = .01) and a subjective reduction in mitotic activity (P = .03) after decompression. There were no statistically significant changes in the expression of proliferation markers. An increase in daughter-cysts or epithelial rests was seen after decompression (P = .04). Recurrence was noted in four of 16 cases, and expression of p53 was strongly correlated with prolonged duration of treatment (P = .01) and intense inflammatory changes (P = .02). Structural changes in the KCOT epithelium or capsule following decompression facilitate surgical removal of the tumor. There was no statistical evidence that decompression influences expression of proliferation markers in the lining, indicating that the potential for recurrence may not be restricted to the cellular level. The statistically significant increase of p53 expression with increased duration of treatment and increase of inflammation may also indicate the possibility of higher rates of recurrence with prolonged treatment and significant inflammatory changes. Crown Copyright © 2016. Published by Elsevier Inc. All rights reserved.

  9. Cost-Effectiveness of Postoperative Ketamine in Chiari Decompression. (United States)

    McDowell, Michael M; Alhourani, Ahmad; Pearce-Smith, Beverly A; Mazurkiewicz, Anna; Friedlander, Robert M


    In Chiari I patients, postoperative pain and discomfort frequently slow the transition back to the home setting. We sought to determine the effect of standardized ketamine infusion protocols on hospital length of stay (LOS). This retrospective cohort study reviewed 100 consecutive adult patients undergoing Chiari I decompression. Fifty-nine patients were placed on a 2-3 mg/hr ketamine drip until postoperative day 1. This group was compared with a group who received 2-3 mg/hr of ketamine until postoperative day 2 (19 patients) and patients who did not receive ketamine at all (22 patients). Clinical characteristics, opioid use, LOS, and relative hospitalization costs were assessed. All narcotic amounts were converted into milligram equivalents of morphine. LOS of the short-ketamine group was 46.5 hours when compared with the long-ketamine group (66.8 hours) and no-ketamine group (56.9 hours). There was a statistically significant difference when comparing the short-ketamine group with the long-ketamine group and no-ketamine group together (P ketamine protocol was used (P ketamine group, 196 mg in the long-ketamine group, and 187 mg in the no-ketamine group (P = 0.65). No adverse events from ketamine were noted. Ketamine at subanesthetic levels may be an effective tool to facilitate early return home postoperatively and may significantly reduce medical costs. Copyright © 2017 Elsevier Inc. All rights reserved.

  10. Habitat Options to Protect Against Decompression Sickness on Mars (United States)

    Conkin, J.


    Men and women are alive today, although perhaps still in diapers, who will explore the surface of Mars. Two achievable goals to enable this exploration are to use Martian resources, and to provide a safe means for unrestricted access to the surface. A cost-effective approach for Mars exploration is to use the available resources, such as water and atmospheric gases. Nitrogen (N2) and Argon (Ar) in a concentration ratio of 1.68/1.0 are available, and could form the inert gas component of a habitat atmosphere at 8.0, 9.0, or 10.0 pounds per square inch absolute (psia). The habitat and space suit must be designed as an integrated, complementary, system: a comfortable living environment about 85% of the time and a safe working environment about 15% of the time. A goal is to provide a system that permits unrestricted exploration of Mars. However the risk of decompression sickness (DCS) during the extravehicular activity (EVA) in a 3.75 psia suit after exposure to either of the three habitat conditions may limit unrestricted exploration.

  11. Inner ear decompression sickness in compressed-air diving. (United States)

    Klingmann, Christoph


    Inner ear decompression sickness (IEDCS) has become more frequently reported in recreational diving. We examined 34 divers after IEDCS and analyzed their dive profiles, pattern of symptoms, time of symptom onset and the association with a right-to left shunt (r/l shunt). Four divers used mixed gas and were excluded from the analysis. Of the remaining 30 divers, 25 presented with isolated IEDCS alone, while five divers had additional skin and neurological symptoms. All divers presented with vertigo (100%), and 12 divers reported additional hearing loss (40%). All symptoms occurred within 120 minutes (median 30 minutes) of ascent. Twenty-two of 30 divers (73.3%) showed a r/l shunt. A possible explanation for the frequent association of a r/l shunt and the dominance of vestibular rather than cochlear symptoms could be attributed to the different blood supply of the inner ear structures and the different size of the labyrinthine compartments. The cochlea has a blood supply up to four times higher than the vestibular part of the inner ear, whereas the vestibular fluid space is 30% larger. The higher prevalence of symptoms referrable to the less well-perfused vestibular organ provides further evidence that persistent local inert gas supersaturation may cause growth of incoming arterial bubbles and may therefore be an important pathophysiological factor in IEDCS.

  12. Towards new paradigms for the treatment of hypobaric decompression sickness. (United States)

    Dart, T S; Butler, W


    Altitude induced (hypobaric) decompression sickness (DCS) has long been treated with ground level oxygen and U.S. Navy Treatment Tables 5 and 6. These treatment tables originate from surface excursion diving and, when implemented, require significant resource allocation. Although they are effective treatment regimens, these tables were not developed for treating hypobaric DCS which has an etiology similar to saturation diving DCS. In this review, different treatment options for hypobaric DCS are presented. These options include more aggressive use of ground level oxygen and treatment tables using a maximum pressure of 2 atmospheres (ATA). Specific attention is given to USAF Table VIII, an experimental hypobaric DCS treatment-table, and space suit overpressurization treatment. This paradigm shift for DCS treatment is based on a projected increase in hypobaric DCS treatment from exposure to low pressure during several operational conditions: cruise flight in the next generation aircraft (e.g., F-22); high altitude, unpressurized flight by special operations forces; and the extraordinary amount of extravehicular activity (EVA) required to construct the international space station. Anticipating the need to treat DCS encountered during these and other activities, it is proposed that 2 ATA or less hyperbaric oxygen (HBO) treatment conjoined with new collapsible chamber technology can be used to address these issues in a safe and cost effective fashion.

  13. Endoscopic optic nerve decompression for nontraumatic compressive optic neuropathy

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    Cheng-long REN


    Full Text Available Objective To describe the preliminary experience with endoscopic optic nerve decompression (EOND for nontraumatic compressive optic neuropathies (NCONs. Methods The clinical data of 10 patients, male 5 and female 5, with a mean age of 44.3±5.1 years, who underwent EOND for visual loss (n=5 or visual deterioration (n=5 due to tumor compression in General Hospital of Armed Police Forces of China in the period from April 2013 to April 2014 were analyzed retrospectively. Preoperative and 6-month-postoperative clinical and imaging data of these patients were reviewed and analyzed. Results Among 5 patients who lost light perception (including 2 patients with bilateral optic nerve compression before operation, 4 of them showed visual improvement to different degrees on the 7th day after operation (with improvement of bilateral visual acuity. The other 5 patients with visual impairment before operation recovered their visual acuity to different extent after the operation. All of the patients had no obvious post-operative complications. Conclusion EOND is a safe, effective, and minimally invasive surgical technique affording recovery of visual function to NCON patients. DOI: 10.11855/j.issn.0577-7402.2015.11.12

  14. Gas and particle motions in a rapidly decompressed flow (United States)

    Johnson, Blair; Zunino, Heather; Adrian, Ronald; Clarke, Amanda


    To understand the behavior of a rapidly decompressed particle bed in response to a shock, an experimental study is performed in a cylindrical (D = 4.1 cm) glass vertical shock tube of a densely packed (ρ = 61%) particle bed. The bed is comprised of spherical glass particles, ranging from D50 = 44-297 μm between experiments. High-speed pressure sensors are incorporated to capture shock speeds and strengths. High-speed video and particle image velocimetry (PIV) measurements are collected to examine vertical and radial velocities of both the particles and gas to elucidate features of the shock wave and resultant expansion wave in the lateral center of the tube, away from boundaries. In addition to optically analyzing the front velocity of the rising particle bed, interaction between the particle and gas phases are investigated as the flow accelerates and the particle front becomes more dilute. Particle and gas interactions are also considered in exploring mechanisms through which turbulence develops in the flow. This work is supported by the U.S. Department of Energy, National Nuclear Security Administration, Advanced Simulation and Computing Program, as a Cooperative Agreement under the Predictive Science and Academic Alliance Program, under Contract No. DE-NA0002378.

  15. Herniation despite Decompressive Hemicraniectomy in Large Hemispherical Ischemic Strokes. (United States)

    Hinduja, Archana; Samant, Rohan; Feng, Dongxia; Hannawi, Yousef


    Despite decompressive hemicraniectomy (DHC), progressive herniation resulting in death has been reported following middle cerebral artery (MCA) strokes. We aimed to determine the surgical parameters measured on brain computed tomography (CT) scan that are associated with progressive herniation despite DHC in large MCA strokes. Retrospective chart review of medical records of patients with malignant hemispheric infarction who underwent DHC for cerebral edema was performed. Infarct volume was calculated on CT scans obtained within 24 hours of ictus. Radiological parameters of craniectomy bone flap size, brain volume protruding out of the skull, adequate centering of the craniectomy over the stroke bed, and the infarct volume outside the craniectomy bed (volume not centered [VNC]) were measured on the postoperative brain CT. Of 41 patients who underwent DHC, 7 had progressive herniation leading to death. Radiographic parameters significantly associated with progressive herniation included insufficient centering of craniectomy bed on the stroke bed (P = .03), VNC (P = .011), additional anterior cerebral artery infarction (P = .047), and smaller craniectomy length (P = .05). Multivariate logistic regression analysis for progressive herniation using craniectomy length and VNC as independent variables demonstrated that a higher VNC was significantly associated with progressive herniation despite surgery (P = .029). In large MCA strokes, identification of large infarct volume outside the craniectomy bed was associated with progressive herniation despite surgery. These results will need to be verified in larger prospective studies. Copyright © 2018 National Stroke Association. Published by Elsevier Inc. All rights reserved.

  16. Type II decompression sickness in a hyperbaric inside attendant. (United States)

    Johnson-Arbor, Kelly


    Decompression sickness (DCS) of an inside attendant (IA) is rarely encountered in hyperbarics. This report describes an IA who developed Type II DCS after a routine hyperbaric exposure. A 50-year-old male complained of lower extremity weakness and paresthesias after serving as an IA during a hyperbaric treatment to 40 fsw (122.52 kPa). Within 10 minutes after the conclusion of the treatment, the IA experienced irritability and confusion, and was unable to walk. Physical examination revealed decreased sensation below the T7 level, and decreased strength in the lower extremities. Type II DCS was diagnosed, and the IA was recompressed to 60 fsw (183.78 kPa) on a U.S. Navy Treatment Table 6, which resulted in improvement of his symptoms. Transthoracic echocardiography with bubble study performed 16 months after the event demonstrated a large patent foramen ovale (PFO). Increased age, decreased physical fitness and the undiagnosed PFO may have predisposed this attendant to developing DCS. Although rare, DCS may occur in IAs. Routine monitoring and reporting of the long-term health of hyperbaric IAs should be considered by hyperbaric facilities and medical directors in order to further understand the characteristics of DCS and other hyperbaric-related conditions in these workers.

  17. Decompression Device Using a Stainless Steel Tube and Wire for Treatment of Odontogenic Cystic Lesions: A Technical Report. (United States)

    Jung, Eun-Joo; Baek, Jin-A; Leem, Dae-Ho


    Decompression is considered an effective treatment for odontogenic cystic lesions in the jaw. A variety of decompression devices are successfully used for the treatment of keratocystic odontogenic tumors, radicular cysts, dentigerous cysts, and ameloblastoma. The purpose of these devices is to keep an opening between the cystic lesion and the oral environment during treatment. The aim of this report is to describe an effective decompression tube using a stainless steel tube and wire for treatment of jaw cystic lesions.

  18. Modified “in-window” technique for decompressive craniotomy for severe brain injury

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    Jovanović Momir J.


    Full Text Available Increased intracranial pressure and decreased cerebral perfusion in patients with severe traumatic brain injury are associated with cerebral ischemia and poor outcome. Lowering intracranial pressure is one of the goals of treatment. We analyzed the effects of decompressive craniotomy on intracranial pressure levels and outcome. In addition, we compared the results of decompressive craniotomy performed with our original technique (modified “in-window” technique, with no need for cranioplasty with results of classic techniques. We formed two groups: 52 patients with TBI (GCS≤8, with monitored intracranial pressure, and the control: 45 patients without intracranial pressure monitoring. In the first group, malignant intracranial hypertension was treated by decompressive craniotomy, using a modified "in-window" technique. Results were analyzed using standard statistical methods. In the first group, with intracranial pressure monitoring, 17/52 had decompressive craniotomy, and significant reduction of intracranial pressure appeared in the early postoperative period (38.82 to 22.76 mmHg, mean, with significant decrease of intracranial pressure at the end of treatment, compared to the control group (mean=25.00, and 45.30 mmHg, respectively. Late complications were similar to results of other studies. Our results were 20% of epileptic seizures, 8% of hydrocephalus, 12% contusion/hematoma progression and 12% subdural hygroma. Outcome (measured with Glasgow Outcome Score-GOS in the first group, at the time of discharge, was better with decompressive craniotomy than without decompressive craniotomy (GOS=2.47, and GOS=1.00, respectively. Modified "in-window" technique for decompressive craniotomy in severe traumatic brain injury is safe, promising and according to our experience offers a lower rate of complications with no need for additional cranioplastic surgery.

  19. Sagittal imbalance in patients with lumbar spinal stenosis and outcomes after simple decompression surgery. (United States)

    Shin, E Kyung; Kim, Chi Heon; Chung, Chun Kee; Choi, Yunhee; Yim, Dahae; Jung, Whei; Park, Sung Bae; Moon, Jung Hyeon; Heo, Won; Kim, Sung-Mi


    Lumbar spinal stenosis (LSS) is the most common lumbar degenerative disease, and sagittal imbalance is uncommon. Forward-bending posture, which is primarily caused by buckling of the ligamentum flavum, may be improved via simple decompression surgery. The objectives of this study were to identify the risk factors for sagittal imbalance and to describe the outcomes of simple decompression surgery. This is a retrospective nested case-control study PATIENT SAMPLE: This was a retrospective study that included 83 consecutive patients (M:F=46:37; mean age, 68.5±7.7 years) who underwent decompression surgery and a minimum of 12 months of follow-up. The primary end point was normalization of sagittal imbalance after decompression surgery. Sagittal imbalance was defined as a C7 sagittal vertical axis (SVA) ≥40 mm on a 36-inch-long lateral whole spine radiograph. Logistic regression analysis was used to identify the risk factors for sagittal imbalance. Bilateral decompression was performed via a unilateral approach with a tubular retractor. The SVA was measured on serial radiographs performed 1, 3, 6, and 12 months postoperatively. The prognostic factors for sagittal balance recovery were determined based on various clinical and radiological parameters. Sagittal imbalance was observed in 54% (45/83) of patients, and its risk factors were old age and a large mismatch between pelvic incidence and lumbar lordosis. The 1-year normalization rate was 73% after decompression surgery, and the median time to normalization was 1 to 3 months. Patients who did not experience SVA normalization exhibited low thoracic kyphosis (hazard ratio [HR], 1.04; 95% confidence interval [CI], 1.02-1.10) (pimbalance was observed in more than 50% of LSS patients, but this imbalance was correctable via simple decompression surgery in 70% of patients. Copyright © 2016 Elsevier Inc. All rights reserved.

  20. MRI Evaluation of Post Core Decompression Changes in Avascular Necrosis of Hip. (United States)

    Nori, Madhavi; Marupaka, Sravan Kumar; Alluri, Swathi; Md, Naseeruddin; Irfan, Kazi Amir; Jampala, Venkateshwarlu; Apsingi, Sunil; Eachempati, Krishna Kiran


    Avascular necrosis of hip typically presents in young patients. Core decompression in precollapse stage provides pain relief and preservation of femoral head. The results of core decompression vary considerably despite early diagnosis. The role of MRI in monitoring patients post surgically has not been clearly defined. To study pre and post core decompression MRI changes in avascular necrosis of hip. This is a contiguous observational cohort of 40 hips treated by core decompression for precollapse avascular necrosis of femoral head, who had a baseline MRI performed before surgery. Core decompression of the femoral head was performed within 4 weeks. Follow up radiograph and MRI scans were done at six months. Harris hip score preoperatively, 1 month and 6 months after the surgery was noted. Success in this study was defined as postoperative increase in Harris hip score (HHS) by 20 points and no additional femoral collapse. End point of clinical adverse outcome as defined by fall in Harris hip score was conversion or intention to convert to total hip replacement (THR). MRI parameters in the follow up scan were compared to the preoperative MRI. Effect of core decompression on bone marrow oedema and femoral head collapse was noted. Results were analysed using SPSS software version. Harris hip score improved from 57 to 80 in all patients initially. Six hips had a fall in Harris hip score to mean value of 34.1 during follow up (9 to 12 months) and underwent total hip replacement. MRI predictors of positive outcome are lesions with grade A extent, Grade A & B location. Bone marrow oedema with lesions less than 50% involvement, medial and central location. Careful selection of patients by MR criteria for core decompression provides satisfactory outcome in precollapse stage of avascular necrosis of hip.

  1. Teflon granulomas mimicking cerebellopontine angle tumors following microvascular decompression. (United States)

    Deep, Nicholas L; Graffeo, Christopher S; Copeland, William R; Link, Michael J; Atkinson, John L; Neff, Brian A; Raghunathan, Aditya; Carlson, Matthew L


    To report two patients with a history of microvascular decompression (MVD) for hemifacial spasm who presented with Teflon granulomas (TG) mimicking cerebellopontine angle (CPA) tumors and to perform a systematic review of the English-language literature. Case series at a single tertiary academic referral center and systematic review. Retrospective chart review with analysis of clinical, radiological, and histopathological findings. Systematic review using PubMed, Embase, MEDLINE, and Web of Science databases. Two patients with large skull base TGs mimicking CPA tumors clinically and radiographically were managed at the authors' institution. The first presented 4 years after MVD with asymmetrical sensorineural hearing loss, multiple progressive cranial neuropathies, and brainstem edema due to a growing TG. Reoperation with resection of the granuloma confirmed a foreign-body reaction consisting of multinucleated giant cells containing intracytoplasmic Teflon particles. The second patient presented 11 years after MVD with asymmetrical sensorineural hearing loss and recurrent hemifacial spasm. No growth was noted over 2 years, and the patient has been managed expectantly. Only one prior case of TG after MVD for hemifacial spasm has been reported in the English literature. TG is a rare complication of MVD for hemifacial spasm. The diagnosis should be suspected in patients presenting with a new-onset enhancing mass of the CPA after MVD, even when performed decades earlier. A thorough clinical and surgical history is critical toward establishing an accurate diagnosis to guide management and prevent unnecessary morbidity. Surgical intervention is not required unless progressive neurologic complications ensue. 4 Laryngoscope, 127:715-719, 2017. © 2016 The American Laryngological, Rhinological and Otological Society, Inc.

  2. Association of microparticles and neutrophil activation with decompression sickness. (United States)

    Thom, Stephen R; Bennett, Michael; Banham, Neil D; Chin, Walter; Blake, Denise F; Rosen, Anders; Pollock, Neal W; Madden, Dennis; Barak, Otto; Marroni, Alessandro; Balestra, Costantino; Germonpre, Peter; Pieri, Massimo; Cialoni, Danilo; Le, Phi-Nga Jeannie; Logue, Christopher; Lambert, David; Hardy, Kevin R; Sward, Douglas; Yang, Ming; Bhopale, Veena B; Dujic, Zeljko


    Decompression sickness (DCS) is a systemic disorder, assumed due to gas bubbles, but additional factors are likely to play a role. Circulating microparticles (MPs)--vesicular structures with diameters of 0.1-1.0 μm--have been implicated, but data in human divers have been lacking. We hypothesized that the number of blood-borne, Annexin V-positive MPs and neutrophil activation, assessed as surface MPO staining, would differ between self-contained underwater breathing-apparatus divers suffering from DCS vs. asymptomatic divers. Blood was analyzed from 280 divers who had been exposed to maximum depths from 7 to 105 meters; 185 were control/asymptomatic divers, and 90 were diagnosed with DCS. Elevations of MPs and neutrophil activation occurred in all divers but normalized within 24 h in those who were asymptomatic. MPs, bearing the following proteins: CD66b, CD41, CD31, CD142, CD235, and von Willebrand factor, were between 2.4- and 11.7-fold higher in blood from divers with DCS vs. asymptomatic divers, matched for time of sample acquisition, maximum diving depth, and breathing gas. Multiple logistic regression analysis documented significant associations (P < 0.001) between DCS and MPs and for neutrophil MPO staining. Effect estimates were not altered by gender, body mass index, use of nonsteroidal anti-inflammatory agents, or emergency oxygen treatment and were modestly influenced by divers' age, choice of breathing gas during diving, maximum diving depth, and whether repetitive diving had been performed. There were no significant associations between DCS and number of MPs without surface proteins listed above. We conclude that MP production and neutrophil activation exhibit strong associations with DCS. Copyright © 2015 the American Physiological Society.

  3. Supraorbital keyhole surgery for optic nerve decompression and dura repair. (United States)

    Chen, Yuan-Hao; Lin, Shinn-Zong; Chiang, Yung-Hsiao; Ju, Da-Tong; Liu, Ming-Ying; Chen, Guann-Juh


    Supraorbital keyhole surgery is a limited surgical procedure with reduced traumatic manipulation of tissue and entailing little time in the opening and closing of wounds. We utilized the approach to treat head injury patients complicated with optic nerve compression and cerebrospinal fluid leakage (CSF). Eleven cases of basal skull fracture complicated with either optic nerve compression and/or CSF leakage were surgically treated at our department from February 1995 to June 1999. Six cases had primary optic nerve compression, four had CSF leakage and one case involved both injuries. Supraorbital craniotomy was carried out using a keyhole-sized burr hole plus a small craniotomy. The size of craniotomy approximated 2 x 3 cm2. The optic nerve was decompressed via removal of the optic canal roof and anterior clinoid process with high-speed drills. The defect of dura was repaired with two pieces of tensa fascia lata that were attached on both sides of the torn dural defect with tissue glue. Seven cases with optic nerve injury included five cases of total blindness and two cases of light perception before operation. Vision improved in four cases. The CSF leakage was stopped successfully in all four cases without complication. As optic nerve compression and CSF leakage are skull base lesions, the supraorbital keyhole surgery constitutes a suitable approach. The supraorbital keyhole surgery allows for an anterior approach to the skull base. This approach also allows the treatment of both CSF leakage and optic nerve compression. Our results indicate that supraorbital keyhole operation is a safe and effective method for preserving or improving vision and attenuating CSF leakage following injury.

  4. Outcome after decompressive craniectomy for the treatment of severe traumatic brain injury. (United States)

    Howard, Jerry Lee; Cipolle, Mark D; Anderson, Meredith; Sabella, Victoria; Shollenberger, Daniele; Li, P Mark; Pasquale, Michael D


    Using decompressive craniectomy as part of the treatment regimen for severe traumatic brain injury (STBI) has become more common at our Level I trauma center. This study was designed to examine this practice with particular attention to long-term functional outcome. A retrospective review of prospectively collected data was performed for patients with STBI admitted from January 1, 2003 to December 31, 2005. Our institution manages patients using the Brain Trauma Foundation Guidelines. Data collected from patients undergoing decompressive craniectomy included: age, Injury Severity Score, admission and follow-up Glasgow Coma Score, timing of, and indication for decompressive craniectomy, and procedure-related complications. The Extended Glasgow Outcome Scale (GOSE) was performed by a experienced trauma clinical research coordinator using a structured phone interview to assess long-term outcome in the survivors. Student's t test and chi2 were used to examine differences between groups. Forty STBI patients were treated with decompressive craniectomy; 24 were performed primarily in conjunction with urgent evacuation of extra-axial hemorrhage and 16 were performed primarily in response to increased intracranial pressure with 4 of these after an initial craniotomy. Decompressive craniectomy was very effective at lowering intracranial pressure in these 16 patients (35.0 mm Hg +/- 13.5 mm Hg to 14.6 mm Hg +/- 8.7 mm Hg, p = 0.005). Twenty-two decompressive craniectomy patients did not survive to hospital discharge, whereas admission Glasgow Coma Score and admission pupil size and reactivity correlated with outcome, age, and Injury Severity Score did not. At a mean of 11 months (range, 3-26 months) after decompressive craniectomy, 6 survivors had a poor functional outcome (GOSE 1-4), whereas 12 survivors had a good outcome (GOSE 5-8). Therefore, 70% of these patients had an unfavorable outcome (death or severe disability), and 30% had a favorable long-term functional outcome

  5. Assessment of Barotrauma Resulting from Rapid Decompression of Depth Acclimated Juvenile Chinook Salmon Bearing Radio Telemetry Transmitters

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    Brown, Richard S.; Carlson, Thomas J.; Welch, Abigail E.; Stephenson, John R.; Abernethy, Cary S.; McKinstry, Craig A.; Theriault, Marie-Helene


    A multifactor study was conducted by Battelle for the US Army Corps of Engineers to assess the significance of the presence of a radio telemetry transmitter on the effects of rapid decompression from simulated hydro turbine passage on depth acclimated juvenile run-of-the-river Chinook salmon. Study factors were: (1) juvenile chinook salmon age;, subyearling or yearling, (2) radio transmitter present or absent, (3) three transmitter implantation factors: gastric, surgical, and no transmitter, and (4) four acclimation depth factors: 1, 10, 20, and 40 foot submergence equivalent absolute pressure, for a total of 48 unique treatments. Exposed fish were examined for changes in behavior, presence or absence of barotrauma injuries, and immediate or delayed mortality. Logistic models were used to test hypotheses that addressed study objectives. The presence of a radio transmitter was found to significantly increase the risk of barotrauma injury and mortality at exposure to rapid decompression. Gastric implantation was found to present a higher risk than surgical implantation. Fish were exposed within 48 hours of transmitter implantation so surgical incisions were not completely healed. The difference in results obtained for gastric and surgical implantation methods may be the result of study design and the results may have been different if tested fish had completely healed surgical wounds. However, the test did simulate the typical surgical-release time frame for in-river telemetry studies of fish survival so the results are probably representative for fish passing through a turbine shortly following release into the river. The finding of a significant difference in response to rapid decompression between fish bearing radio transmitters and those not implies a bias may exist in estimates of turbine passage survival obtained using radio telemetry. However, the rapid decompression (simulated turbine passage) conditions used for the study represented near worst case exposure

  6. "White Cord Syndrome" of Acute Hemiparesis After Posterior Cervical Decompression and Fusion for Chronic Cervical Stenosis. (United States)

    Antwi, Prince; Grant, Ryan; Kuzmik, Gregory; Abbed, Khalid


    "White cord syndrome" is a very rare condition thought to be due to acute reperfusion of chronically ischemic areas of the spinal cord. Its hallmark is the presence of intramedullary hyperintense signal on T2-weighted magnetic resonance imaging sequences in a patient with unexplained neurologic deficits following spinal cord decompression surgery. The syndrome is rare and has been reported previously in 2 patients following anterior cervical decompression and fusion. We report an additional case of this complication. A 68-year-old man developed acute left-sided hemiparesis after posterior cervical decompression and fusion for cervical spondylotic myelopathy. The patient improved with high-dose steroid therapy. The rare white cord syndrome following either anterior cervical decompression and fusion or posterior cervical decompression and fusion may be due to ischemic-reperfusion injury sustained by chronically compressed parts of the spinal cord. In previous reports, patients have improved following steroid therapy and acute rehabilitation. Copyright © 2018 Elsevier Inc. All rights reserved.

  7. Optic neuropathy in thyroid eye disease: results of the balanced decompression technique. (United States)

    Baril, Catherine; Pouliot, Denis; Molgat, Yvonne


    To determine the efficacy of combined endoscopic medial and external lateral orbital decompression for the treatment of compressive optic neuropathy (CON) in thyroid eye disease (TED). A retrospective review of all patients undergoing combined surgical orbital decompression for CON between 2000 and 2010 was conducted. Fifty-nine eyes of 34 patients undergoing combined surgical orbital decompression for CON. Clinical outcome measures included visual acuity, Hardy-Rand-Rittler (HRR) colour plate testing, relative afferent pupillary defect, intraocular pressure measurement, and Hertel exophthalmometry. A CON score was calculated preoperatively and postoperatively based on the visual acuity and the missed HRR plates. A higher CON score correlates with more severe visual dysfunction. All patients had improvement of their optic neuropathy after surgical decompression. CON score was calculated for 54 eyes and decreased significantly from a mean of 13.2 ± 10.35 preoperatively to a mean of 8.51 ± 10.24 postoperatively (p < 0.0001). Optic neuropathy was completely resolved in 93.22% (55/59 eyes). Eighteen of 34 patients (52.94%) experienced development of new-onset postoperative strabismus that required subsequent surgical intervention. Endoscopic medial combined with external lateral orbital decompression is an effective technique for the treatment of TED-associated CON. © 2013 Canadian Ophthalmological Society Published by Canadian Ophthalmological Society All rights reserved.

  8. A comparative study of the intracranial environment before and after cranioplasty in decompressive craniectamized cases

    International Nuclear Information System (INIS)

    Utsugi, Osamu; Saito, Fumio; Inaba, Izumi; Takeda, Yasuaki; Miki, Tamotsu; Miwa, Tetsurou


    The external decompression is performed as a secondary method for the surgical treatment of increased intracranial pressure due to trauma or cerebrovascular disease. We have had the experience that, if patients are kept in a decompressed state for a prolonged period, they often complain of various minor neurological disorders; cranioplasty done on such patients improves those disorders. In this investigation, the authors made a plan to elucidate this mechanism. The subjects were 30 cases of non-progressive diseases, such as postoperative lesions of ruptured aneurysms, and intracerebral hematomas. We proved that the cerebral function improves after the cranioplasty by an average score of 5.7 on Hasegawa's simple intelligent evaluation scale and by 88.9% in EEG. The morphological change was observed by a CT scan, which showed as a compressive deformity of the lateral ventricle, subdural fluid collection, and a prolonged residue of brain edema. These findings were rapidly and greatly improved after the cranioplasty. It was also found, by the measurement of the regional cerebral blood flow by means of SPECT, that the hemicerebral blood flow rate on the side of the decompressive craniectomy was significantly improved after the cranioplasty compared with the control group. From the above data, it was presumed that the persistence of neurological disorders in decompressive craniectomy is caused largely by a regional cerebral blood flow disorder. Therefore, the authors considered that, when external decompression is done, it is essential to perform cranioplasty as soon as possible after the intracranial pressure has been relieved. (author)

  9. Deadly diving? Physiological and behavioural management of decompression stress in diving mammals (United States)

    Hooker, S. K.; Fahlman, A.; Moore, M. J.; Aguilar de Soto, N.; Bernaldo de Quirós, Y.; Brubakk, A. O.; Costa, D. P.; Costidis, A. M.; Dennison, S.; Falke, K. J.; Fernandez, A.; Ferrigno, M.; Fitz-Clarke, J. R.; Garner, M. M.; Houser, D. S.; Jepson, P. D.; Ketten, D. R.; Kvadsheim, P. H.; Madsen, P. T.; Pollock, N. W.; Rotstein, D. S.; Rowles, T. K.; Simmons, S. E.; Van Bonn, W.; Weathersby, P. K.; Weise, M. J.; Williams, T. M.; Tyack, P. L.


    Decompression sickness (DCS; ‘the bends’) is a disease associated with gas uptake at pressure. The basic pathology and cause are relatively well known to human divers. Breath-hold diving marine mammals were thought to be relatively immune to DCS owing to multiple anatomical, physiological and behavioural adaptations that reduce nitrogen gas (N2) loading during dives. However, recent observations have shown that gas bubbles may form and tissue injury may occur in marine mammals under certain circumstances. Gas kinetic models based on measured time-depth profiles further suggest the potential occurrence of high blood and tissue N2 tensions. We review evidence for gas-bubble incidence in marine mammal tissues and discuss the theory behind gas loading and bubble formation. We suggest that diving mammals vary their physiological responses according to multiple stressors, and that the perspective on marine mammal diving physiology should change from simply minimizing N2 loading to management of the N2 load. This suggests several avenues for further study, ranging from the effects of gas bubbles at molecular, cellular and organ function levels, to comparative studies relating the presence/absence of gas bubbles to diving behaviour. Technological advances in imaging and remote instrumentation are likely to advance this field in coming years. PMID:22189402

  10. Decompression illness in goats following simulated submarine escape: 1993-2006. (United States)

    Seddon, F M; Thacker, J C; Fisher, A S; Jurd, K M; White, M G; Loveman, G A M


    The United Kingdom Ministry of Defence commissioned work to define the relationship between the internal pressure of a distressed submarine (DISSUB), the depth from which escape is made and the risk of decompression illness (DCI). The program of work used an animal model (goat) to define these risks and this paper reports the incidence and type of DCI observed. A total of 748 pressure exposures comprising saturation only, escape only or saturation followed by escape were conducted in the submarine escape simulator between 1993 and 2006. The DCI following saturation exposures was predominantly limb pain, whereas following escape exposures the DCI predominantly involved the central nervous system and was fast in onset. There was no strong relationship between the risk of DCI and the range of escape depths investigated. The risk of DCI incurred from escape following saturation was greater than that obtained by combining the risks for the independent saturation only, and escape only, exposures. The output from this program of work has led to improved advice on the safety of submarine escape.

  11. Zero-dimensional analysis of burn control with compression-decompression

    International Nuclear Information System (INIS)

    Okamoto, Masao; Ohnishi, Masami


    A simple but realistic method of active feedback control of a self-ignited tokamak reactor by major radius compression-decompression is presented, in which the thermal fusion output power and the ion temperature are envisaged as the variables that could be adopted as object of control. Error inherent in the measuring system for the controlled variable is taken into account in the analysis. Numerical calculations based on a point reactor model are performed, which indicate that the proposed method of control is capable of completely suppressing thermal runaway without involving any significant change in the major radius or in the fusion output power. Matching the reactor output to changes in load is shown also to be possible from a numerical example. The thermal stability of an igniting plasma governed by this feedback control is analyzed without prescribing any particular transport scaling. It is revealed that the control is achievable for a suitably chosen gain even with a response time lag longer than the thermal runaway time. Strong dependence of the stability on the scaling law is indicated. (author)

  12. Tariff design for communication-capable metering systems in conjunction with time-variant electricity consumption rates; Gestaltung von Tarifen fuer kommunikationsfaehige Messsysteme im Verbund mit zeitvariablen Stromtarifen. Eine empirische Analyse von Praeferenzen privater Stromkunden in Deutschland

    Energy Technology Data Exchange (ETDEWEB)

    Gerpott, Torsten J.; Paukert, Mathias [Duisburg-Essen Univ., Duisburg (Germany). Lehrstuhl Unternehmens- und Technologieplanung, Schwerpunkt Telekommunikationswirtschaft


    In Germany too, communication-capable electricity metering systems (CMS) together with time-based differentiation of kWh-rates for energy consumption are increasingly proliferated among household customers. Nevertheless, empirical evidence with respect to preferences of members of this customer group for the design of CMS tariff elements and of time-variant electricity consumption rates is still scarce. The present study captures such preferences by means of conjoint analysis of data obtained in an online survey of 754 German-speaking adults. Examined CMS tariff elements are a one-off installation fee and monthly recurring use charges. The studied characteristics of time-based rates are the number of time/tariff blocks, the maximum spread between kWh-rates for different time windows and the adaptability/predictability of kWh-rates. Most respondents judged multidimensional CMS and electricity consumption tariff offerings mainly in light of the CMS tariff characteristics. The vast majority of the participants perceived kWh-rates, which may change with a minimum lead time of one day as reducing the benefit of CMS and consumption tariff bundles. Tariff preferences on the one hand were only rarely significantly related to customers' socio-demographic and electricity procurement characteristics as well as their CMS-related expectations/assessments on the other. The willingness to accept CMS-related one-off installation and recurring service charges as well as the propensity to opt for time-dependent electricity consumption tariff variants differing clearly from non-differentiated electricity price schemes appear to be positively affected by customers' practical application experience with CMS and time-variant electricity consumption rates. Conclusions are drawn for energy suppliers seeking to propagate CMS-based time-variant tariffs among household customers in Germany and for future scholarly research. (orig.)

  13. Phase transitions during compression and decompression of clots from platelet-poor plasma, platelet-rich plasma and whole blood. (United States)

    Liang, Xiaojun; Chernysh, Irina; Purohit, Prashant K; Weisel, John W


    Blood clots are required to stem bleeding and are subject to a variety of stresses, but they can also block blood vessels and cause heart attacks and ischemic strokes. We measured the compressive response of human platelet-poor plasma (PPP) clots, platelet-rich plasma (PRP) clots and whole blood clots and correlated these measurements with confocal and scanning electron microscopy to track changes in clot structure. Stress-strain curves revealed four characteristic regions, for compression-decompression: (1) linear elastic region; (2) upper plateau or softening region; (3) non-linear elastic region or re-stretching of the network; (4) lower plateau in which dissociation of some newly made connections occurs. Our experiments revealed that compression proceeds by the passage of a phase boundary through the clot separating rarefied and densified phases. This observation motivates a model of fibrin mechanics based on the continuum theory of phase transitions, which accounts for the pre-stress caused by platelets, the adhesion of fibrin fibers in the densified phase, the compression of red blood cells (RBCs), and the pumping of liquids through the clot during compression/decompression. Our experiments and theory provide insights into the mechanical behavior of blood clots that could have implications clinically and in the design of fibrin-based biomaterials. The objective of this paper is to measure and mathematically model the compression behavior of various human blood clots. We show by a combination of confocal and scanning electron microscopy that compression proceeds by the passage of a front through the sample that separates a densified region of the clot from a rarefied region, and that the compression/decompression response is reversible with hysteresis. These observations form the basis of a model for the compression response of clots based on the continuum theory of phase transitions. Our studies may reveal how clot rheology under large compression in vivo due

  14. Severe capillary leak syndrome after inner ear decompression sickness in a recreational scuba diver. (United States)

    Gempp, Emmanuel; Lacroix, Guillaume; Cournac, Jean-Marie; Louge, Pierre


    Post-decompression shock with plasma volume deficit is a very rare event that has been observed under extreme conditions of hypobaric and hyperbaric exposure in aviators and professional divers. We report a case of severe hypovolemic shock due to extravasation of plasma in a recreational scuba diver presenting with inner ear decompression sickness. Impaired endothelial function can lead to capillary leak with hemoconcentration and hypotension in severe cases. This report suggests that decompression-induced circulating bubbles may have triggered the endothelial damage, activating the classic inflammatory pathway of increased vascular permeability. This observation highlights the need for an accurate diagnosis of this potentially life-threatening condition at the initial presentation in the Emergency Department after a diving-related injury. An elevated hematocrit in a diver should raise the suspicion for the potential development of capillary leak syndrome requiring specific treatment using albumin infusion as primary fluid replacement. Copyright © 2013 Elsevier Inc. All rights reserved.

  15. Complicated Pseudomeningocele Repair After Chiari Decompression: Case Report and Review of the Literature. (United States)

    De Tommasi, Claudio; Bond, Aaron E


    Pseudomeningocele is a recognised complication after posterior fossa decompression for Chiari malformation. Its management can be challenging and treatment options vary in literature. A difficult-to-treat case of a pseudomeningocele after posterior fossa decompression for a Chiari I malformation is presented. A 34-year-old woman underwent an initial decompression followed by multiple revision surgeries after the development of a symptomatic pseudomeningocele and a low-grade infection. Complications associated with standard treatment modalities, including lumbar drainage and dural repair, are discussed. A review of the existing literature is presented. The reported case ultimately required complete removal of all dural repair materials to eliminate the patient's low-grade infection, a muscular flap, and placement of a ventricular-peritoneal shunt for definitive treatment after a trial of a lumbar drain led to herniation and development of a syrinx. Copyright © 2016 Elsevier Inc. All rights reserved.

  16. General Purpose Graphics Processing Unit Based High-Rate Rice Decompression and Reed-Solomon Decoding

    Energy Technology Data Exchange (ETDEWEB)

    Loughry, Thomas A. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)


    As the volume of data acquired by space-based sensors increases, mission data compression/decompression and forward error correction code processing performance must likewise scale. This competency development effort was explored using the General Purpose Graphics Processing Unit (GPGPU) to accomplish high-rate Rice Decompression and high-rate Reed-Solomon (RS) decoding at the satellite mission ground station. Each algorithm was implemented and benchmarked on a single GPGPU. Distributed processing across one to four GPGPUs was also investigated. The results show that the GPGPU has considerable potential for performing satellite communication Data Signal Processing, with three times or better performance improvements and up to ten times reduction in cost over custom hardware, at least in the case of Rice Decompression and Reed-Solomon Decoding.

  17. Risk Associated With The Decompression Of High Pressure High Temperature Fluids - Study On Black Oil

    DEFF Research Database (Denmark)

    Figueroa, D. C.; Fosbøl, P. L.; Thomsen, K.


    Fluids produced from deep underground reservoirs may result in exponential increase in temperature. It is a consequence of adiabatic fluid decompression from the inverse Joule Thomson Effect (JTE). The phenomenon requires analysis in order to avoid any operational risks. This study evaluates...... the JTE upon decompression of black oil in high pressure-high temperature reservoirs. Also the effect caused by the presence of water and brine on the black oil is studied. The final temperature is calculated from the corresponding energy balance at isenthalpic and non-isenthalpic conditions. It is found...... that the final temperature of black oil increases upon adiabatic decompression. In the case of the isenthalpic process at initial conditions of the reservoir, e.g. 150°C and 1000 bars, it is found that the final temperature can increase to 173.7°C. At non-isenthalpic conditions the final temperature increases...

  18. Prognostic Factors for Satisfaction After Decompression Surgery for Lumbar Spinal Stenosis

    DEFF Research Database (Denmark)

    Paulsen, Rune Tendal; Bouknaitir, Jamal Bech; Fruensgaard, Søren


    : To present clinical outcome data and identify prognostic factors related to patient satisfaction 1 yr after posterior decompression surgery for lumbar spinal stenosis. METHOD: This multicenter register study included 2562 patients. Patients were treated with various types of posterior decompression. Patients...... with previous spine surgery or concomitant fusion were excluded. Patient satisfaction was analyzed for associations with age, sex, body mass index, smoking status, duration of pain, number of decompressed vertebral levels, comorbidities, and patient-reported outcome measures, which were used to quantify....... CONCLUSION: This study found smoking, long duration of leg pain, and cancerous and neurological disease to be associated with patient dissatisfaction, whereas good walking capacity at baseline was positively associated with satisfaction after 1 yr....

  19. MRI-guidance in percutaneous core decompression of osteonecrosis of the femoral head

    Energy Technology Data Exchange (ETDEWEB)

    Kerimaa, Pekka; Vaeaenaenen, Matti; Ojala, Risto; Tervonen, Osmo; Blanco Sequeiros, Roberto [Oulu University Hospital, Department of Radiology (Finland); Hyvoenen, Pekka; Lehenkari, Petri [Oulu University Hospital, Department of Surgery (Finland)


    The purpose of this study was to evaluate the usefulness of MRI-guidance for core decompression of avascular necrosis of the femoral head. Twelve MRI-guided core decompressions were performed on patients with different stages of avascular necrosis of the femoral head. The patients were asked to evaluate their pain and their ability to function before and after the procedure and imaging findings were reviewed respectively. Technical success in reaching the target was 100 % without complications. Mean duration of the procedure itself was 54 min. All patients with ARCO stage 1 osteonecrosis experienced clinical benefit and pathological MRI findings were seen to diminish. Patients with more advanced disease gained less, if any, benefit and total hip arthroplasty was eventually performed on four patients. MRI-guidance seems technically feasible, accurate and safe for core decompression of avascular necrosis of the femoral head. Patients with early stage osteonecrosis may benefit from the procedure. (orig.)

  20. MRI-guidance in percutaneous core decompression of osteonecrosis of the femoral head

    International Nuclear Information System (INIS)

    Kerimaa, Pekka; Vaeaenaenen, Matti; Ojala, Risto; Tervonen, Osmo; Blanco Sequeiros, Roberto; Hyvoenen, Pekka; Lehenkari, Petri


    The purpose of this study was to evaluate the usefulness of MRI-guidance for core decompression of avascular necrosis of the femoral head. Twelve MRI-guided core decompressions were performed on patients with different stages of avascular necrosis of the femoral head. The patients were asked to evaluate their pain and their ability to function before and after the procedure and imaging findings were reviewed respectively. Technical success in reaching the target was 100 % without complications. Mean duration of the procedure itself was 54 min. All patients with ARCO stage 1 osteonecrosis experienced clinical benefit and pathological MRI findings were seen to diminish. Patients with more advanced disease gained less, if any, benefit and total hip arthroplasty was eventually performed on four patients. MRI-guidance seems technically feasible, accurate and safe for core decompression of avascular necrosis of the femoral head. Patients with early stage osteonecrosis may benefit from the procedure. (orig.)

  1. Prognostic significance of blood-brain barrier disruption in patients with severe nonpenetrating traumatic brain injury requiring decompressive craniectomy. (United States)

    Ho, Kwok M; Honeybul, Stephen; Yip, Cheng B; Silbert, Benjamin I


    The authors assessed the risk factors and outcomes associated with blood-brain barrier (BBB) disruption in patients with severe, nonpenetrating, traumatic brain injury (TBI) requiring decompressive craniectomy. At 2 major neurotrauma centers in Western Australia, a retrospective cohort study was conducted among 97 adult neurotrauma patients who required an external ventricular drain (EVD) and decompressive craniectomy during 2004-2012. Glasgow Outcome Scale scores were used to assess neurological outcomes. Logistic regression was used to identify factors associated with BBB disruption, defined by a ratio of total CSF protein concentrations to total plasma protein concentration > 0.007 in the earliest CSF specimen collected after TBI. Of the 252 patients who required decompressive craniectomy, 97 (39%) required an EVD to control intracranial pressure, and biochemical evidence of BBB disruption was observed in 43 (44%). Presence of disruption was associated with more severe TBI (median predicted risk for unfavorable outcome 75% vs 63%, respectively; p = 0.001) and with worse outcomes at 6, 12, and 18 months than was absence of BBB disruption (72% vs 37% unfavorable outcomes, respectively; p = 0.015). The only risk factor significantly associated with increased risk for BBB disruption was presence of nonevacuated intracerebral hematoma (> 1 cm diameter) (OR 3.03, 95% CI 1.23-7.50; p = 0.016). Although BBB disruption was associated with more severe TBI and worse long-term outcomes, when combined with the prognostic information contained in the Corticosteroid Randomization after Significant Head Injury (CRASH) prognostic model, it did not seem to add significant prognostic value (area under the receiver operating characteristic curve 0.855 vs 0.864, respectively; p = 0.453). Biochemical evidence of BBB disruption after severe nonpenetrating TBI was common, especially among patients with large intracerebral hematomas. Disruption of the BBB was associated with more severe

  2. Early versus Late Decompression for Traumatic Spinal Cord Injuries; a Systematic Review and Meta-analysis

    Directory of Open Access Journals (Sweden)

    Mahmoud Yousefifard


    Full Text Available Introduction: Despite the vast number of surveys, no consensus has been reached on the optimum timing of spinal decompression surgery. This systematic review and meta-analysis aimed to compare the effects of early and late spinal decompression surgery on neurologic improvement and post-surgical complications in patients with traumatic spinal cord injuries.Methods: Two independent reviewers carried out an extended search in electronic databases. Data of neurological outcome and post-surgery complication were extracted. Finally, pooled relative risk (RR with a 95% confidence interval (CI was reported for comparing of efficacy of early and late surgical decompression.Results: Eventually 22 studies were included. The pooled RR was 0.77 (95% CI: 0.68-0.89 for at least one grade neurological improvement, and 0.84 (95% CI: 0.77-0.92 for at least two grade improvement. Pooled RR for surgical decompression performed within 12 hours after the injury was 0.26 (95% CI: 0.13-0.52; p<0.001, while it was 0.75 (95% CI: 0.63-0.90; p=0.002 when the procedure was performed within 24 hours, and 0.93 (95% CI: 0.76-1.14; p=0.48 when it was carried out in the first 72 hours after the injury. Surgical decompression performed within 24 hours after injury was found to be associated with significantly lower rates of post-surgical complications (RR=0.77; 95% CI: 0.68-0.86; p<0.001.Conclusion: The findings of this study indicate that early spinal decompression surgery can improve neurologic recovery and is associated with less post-surgical complications. The optimum efficacy is observed when the procedure is performed within 12 hours of the injury.

  3. Cutis marmorata in decompression illness may be cerebrally mediated: a novel hypothesis on the aetiology of cutis marmorata

    NARCIS (Netherlands)

    Kemper, Tom Cpm; Rienks, R.; van Ooij, P. Jam; van Hulst, R. A.


    Cutaneous decompression sickness (DCS) is often considered to be a mild entity that may be explained by either vascular occlusion of skin vessels by bubbles entering the arterial circulation through a right-to-left shunt or bubble formation due to saturated subcutaneous tissue during decompression.

  4. Use of impedance threshold device in conjunction with our novel adhesive glove device for ACD-CPR does not result in additional chest decompression. (United States)

    Shih, Andre; Udassi, Sharda; Porvasnik, Stacy L; Lamb, Melissa A; Badugu, Srinivasarao; Venkata, Giridhar Kaliki; Lopez-Colon, Dalia; Haque, Ikram U; Zaritsky, Arno L; Udassi, Jai P


    To evaluate the hemodynamic effects of using an adhesive glove device (AGD) to perform active compression-decompression CPR (AGD-CPR) in conjunction with an impedance threshold device (ITD) in a pediatric cardiac arrest model. Controlled, randomized animal study. In this study, 18 piglets were anesthetized, ventilated, and continuously monitored. After 3min of untreated ventricular fibrillation, animals were randomized (6/group) to receive either standard CPR (S-CPR), active compression-decompression CPR via adhesive glove device (AGD-CPR) or AGD-CPR along with an ITD (AGD-CPR+ITD) for 2min at 100-120compressions/min. AGD is delivered using a fingerless leather glove with a Velcro patch on the palmer aspect and the counter Velcro patch adhered to the pig's chest. Data (mean±SD) were analyzed using one-way ANOVA with pair wise multiple comparisons to assess differences between groups. p-Value≤0.05 was considered significant. Both AGD-CPR and AGD-CPR+ITD groups produced lower intrathoracic pressure (IttP, mmHg) during decompression phase (-13.4±6.7, p=0.01 and -11.9±6.5, p=0.01, respectively) in comparison to S-CPR (-0.3±4.2). Carotid blood flow (CBF, % of baseline mL/min) was higher in AGD-CPR and AGD-CPR+ITD (respectively 64.3±47.3%, p=0.03 and 67.5±33.1%, p=0.04) as compared with S-CPR (29.1±12.5%). Coronary perfusion pressure (CPP, mmHg) was higher in AGD-CPR and AGD-CPR+ITD (respectively 19.7±4.6, p=0.04 and 25.6±12.1, p=0.02) when compared to S-CPR (9.6±9.1). There was no statistically significant difference between AGD-CPR and AGD-CPR+ITD groups with reference to intra-thoracic pressure, carotid blood flow and coronary perfusion pressure. Active compression decompression delivered by this simple and inexpensive adhesive glove device resulted in improved cerebral blood flow and coronary perfusion pressure. There was no statistically significant added effect of ITD use along with AGD-CPR on the decompression of the chest. Copyright © 2013 Elsevier

  5. Continuous decompression of unicameral bone cyst with cannulated screws: a comparative study. (United States)

    Brecelj, Janez; Suhodolcan, Lovro


    We determined the role of mechanical decompression in the resolution of unicameral bone cyst. A total of 69 children with unicameral bone cysts were treated either by (i) open curettage and bone grafting, (ii) steroid injection or (iii) cannulated screw insertion. During a mean follow-up of 69 months (range, 12-58), the cysts were evaluated by radiological criteria. The healing rates in the three groups were 25, 12 and 29% after the first treatment, and a further 50, 19 and 65% after the second. The study has demonstrated the advantages of the decompression technique for unicameral bone cysts over other treatment modalities studied.

  6. [Developing and testing of decompression regimes for caisson operations while constructing Moscow metro]. (United States)

    Rodchenkov, S V; Syrovegin, A V; Shulagin, I A


    Decompression regimes for caisson operations at the pressures up to 5 ata exceeding duration of the regimes specified in the caisson regulations have been developed. The regimes were tested and validated in dry altitude chamber with participation of exercising human subjects. Seventeen test-subjects took part in 54 tests. No symptoms of decompression sickness were documented. Air embolism was observed in 28 +/- 6% of cases at rest and in 72 +/- 6% of cases following provocative leg movements. The air embolism expression tended to increase with exposure to pressure.

  7. Arthroscopic Resection of The Distal Clavicle With Concomitant Subacromial Decompression: A Case Series

    Directory of Open Access Journals (Sweden)

    HZ Chan


    Full Text Available Shoulder impingement syndrome and acromioclavicular joint osteoarthritis often occur simultaneously and easily missed. Kay et al. reported excellent results with combined arthroscopic subacromial decompression and resection of the distal end of the clavicle in patients with both disorders. Arthroscopic treatment of these disorders produces more favourable results than open procedures. We report two patients who were not responding to conservative management and were treated with direct arthroscopic distal clavicle excision and subacromial decompression in single setting. Both patients gained good postoperative outcome in terms of pain score, function and strength improvement assessed objectively with visual analogue score (VAS and University of California Los Angeles Score (UCLA.

  8. Benefits of hyperbaric oxygen pretreatment for decompression sickness in Bama pigs. (United States)

    Qing, Long; Yi, Hong-Jie; Wang, Ye-Wei; Zhou, Quan; Ariyadewa, Dinesh K; Xu, Wei-Gang


    Decompression sickness (DCS) occurs when ambient pressure is severely reduced during diving and aviation. Hyperbaric oxygen (HBO) pretreatment has been shown to exert beneficial effects on DCS in rats via heat-shock proteins (HSPs). We hypothesized that HBO pretreatment will also reduce DCS via HSPs in swine models. In the first part of our investigation, six swine were subjected to a session of HBO treatment. HSP32, 60, 70 and 90 were detected, before and at 6, 12, 18, 24 and 30 h following exposure in lymphocytes. In the second part of our investigation, another 10 swine were randomly assigned into two groups (five per group). All swine were subjected to two simulated air dives in a hyperbaric chamber with an interval of 7 days. Eighteen hours before each dive, the swine were pretreated with HBO or air: the first group received air pretreatment prior to the first dive and HBO pretreatment prior to the second; the second group were pretreated with HBO first and then air. Bubble loads, skin lesions, inflammation and endothelial markers were detected after each dive. In lymphocytes, all HSPs increased significantly ( P <0.05), with the greatest expression appearing at 18 h for HSP32 and 70. HBO pretreatment significantly reduced all the determined changes compared with air pretreatment. The results demonstrate that a single exposure to HBO 18 h prior to diving effectively protects against DCS in the swine model, possibly via induction of HSPs. © 2018. Published by The Company of Biologists Ltd.

  9. Hemifacial spasm : Intraoperative electromyographic monitoring as a guide for microvascular decompression

    NARCIS (Netherlands)

    Mooij, JJA; Mustafa, MK; van Weerden, TW


    OBJECTIVE: Microvascular decompression is the logical and well-accepted treatment of choice for hemifacial spasm (HFS). In experienced hands, good to excellent results can be obtained. However, sometimes the exact site of the vascular compression is unclear. The aim of this study was to analyze

  10. Analysis of direct costs of decompressive craniectomy in victims of traumatic brain injury. (United States)

    Badke, Guilherme Lellis; Araujo, João Luiz Vitorino; Miura, Flávio Key; Guirado, Vinicius Monteiro de Paula; Saade, Nelson; Paiva, Aline Lariessy Campos; Avelar, Tiago Marques; Pedrozo, Charles Alfred Grander; Veiga, José Carlos Esteves


    Decompressive craniectomy is a procedure required in some cases of traumatic brain injury (TBI). This manuscript evaluates the direct costs and outcomes of decompressive craniectomy for TBI in a developing country and describes the epidemiological profile. A retrospective study was performed using a five-year neurosurgical database, taking a sample of patients with TBI who underwent decompressive craniectomy. Several variables were considered and a formula was developed for calculating the total cost. Most patients had multiple brain lesions and the majority (69.0%) developed an infectious complication. The general mortality index was 68.8%. The total cost was R$ 2,116,960.22 (US$ 661,550.06) and the mean patient cost was R$ 66,155.00 (US$ 20,673.44). Decompressive craniectomy for TBI is an expensive procedure that is also associated with high morbidity and mortality. This was the first study performed in a developing country that aimed to evaluate the direct costs. Prevention measures should be a priority.

  11. Treatment of decompression illness with heliox: the best of both worlds?

    NARCIS (Netherlands)

    van Hulst, Robert A.


    There are many ways to treat decompression illness (DCI) at increased pressure. In the last 20 years much has been published on the use of oxygen and helium/oxygen mixtures at different depths. The type of information ranges from impressive work on animals, case reports, small series of case reports

  12. Women's experiences of daily life after anterior cervical decompression and fusion surgery: A qualitative interview study. (United States)

    Hermansen, Anna; Peolsson, Anneli; Kammerlind, Ann-Sofi; Hjelm, Katarina


    To explore and describe women's experiences of daily life after anterior cervical decompression and fusion surgery. Qualitative explorative design. Fourteen women aged 39-62 years (median 52 years) were included 1.5-3 years after anterior cervical decompression and fusion for cervical disc disease. Individual semi-structured interviews were analysed by qualitative content analysis with an inductive approach. The women described their experiences of daily life in 5 different ways: being recovered to various extents; impact of remaining symptoms on thoughts and feelings; making daily life work; receiving support from social and occupational networks; and physical and behavioural changes due to interventions and encounters with healthcare professionals. This interview study provides insight into women's daily life after anterior cervical decompression and fusion. Whilst the subjects improved after surgery, they also experienced remaining symptoms and limitations in daily life. A variety of mostly active coping strategies were used to manage daily life. Social support from family, friends, occupational networks and healthcare professionals positively influenced daily life. These findings provide knowledge about aspects of daily life that should be considered in individualized postoperative care and rehabilitation in an attempt to provide better outcomes in women after anterior cervical decompression and fusion.

  13. Impact of timing of cranioplasty on hydrocephalus after decompressive hemicraniectomy in malignant middle cerebral artery infarction. (United States)

    Finger, Tobias; Prinz, Vincent; Schreck, Evelyn; Pinczolits, Alexandra; Bayerl, Simon; Liman, Thomas; Woitzik, Johannes; Vajkoczy, Peter


    Patients with malignant middle cerebral artery infarction frequently develop hydrocephalus after decompressive hemicraniectomy. Hydrocephalus itself and known shunt related complications after ventriculo-peritoneal shunt implantation may negatively impact patientś outcome. Here, we aimed to identify factors associated with the development of hydrocephalus after decompressive hemicraniectomy in malignant middle cerebral artery infarction. A total of 99 consecutive patients with the diagnosis of large hemispheric infarctions and the indication for decompressive hemicraniectomy were included. We retrospectively evaluated patient characteristics (gender, age and selected preoperative risk factors), stroke characteristics (side, stroke volume and existing mass effect) and surgical characteristics (size of the bone flap, initial complication rate, time to cranioplasty, complication rate following cranioplasty, type of implant, number of revision surgeries and mortality). Frequency of hydrocephalus development was 10% in our cohort. Patients who developed a hydrocephalus had an earlier time point of bone flap reimplantation compared to the control group (no hydrocephalus=164±104days, hydrocephalus=108±52days, phydrocephalus with a trend towards significance (p=0.08). Communicating hydrocephalus is frequent in patients with malignant middle cerebral artery infarction after decompressive hemicraniectomy. A later time point of cranioplasty might lead to a lower incidence of required shunting procedures in general as we could show in our patient cohort. Copyright © 2016 Elsevier B.V. All rights reserved.

  14. Decompression sickness in a vegetarian diver: are vegetarian divers at risk? A case report

    NARCIS (Netherlands)

    van Hulst, Robert A.; van der Kamp, Wim


    We present a case of a diver who suffered decompression sickness (DCS), but who also was a strict vegetarian for more than 10 years. He presented with symptoms of tingling of both feet and left hand, weakness in both legs and sensory deficits for vibration and propriocepsis after two deep dives with

  15. Assessment of two methods of gastric decompression for the initial management of gastric dilatation-volvulus. (United States)

    Goodrich, Z J; Powell, L L; Hulting, K J


    To assess gastric trocarization and orogastric tubing as a means of gastric decompression for the initial management of gastric dilatation-volvulus. Retrospective review of 116 gastric dilatation-volvulus cases from June 2001 to October 2009. Decompression was performed via orogastric tubing in 31 dogs, gastric trocarization in 39 dogs and a combination of both in 46 dogs. Tubing was successful in 59 (75·5%) dogs and unsuccessful in 18 (23·4%) dogs. Trocarization was successful in 73 (86%) dogs and unsuccessful in 12 (14%) dogs. No evidence of gastric perforation was noted at surgery in dogs undergoing either technique. One dog that underwent trocarization had a splenic laceration identified at surgery that did not require treatment. Oesophageal rupture or aspiration pneumonia was not identified in any dog during hospitalization. No statistical difference was found between the method of gastric decompression and gastric compromise requiring surgical intervention or survival to discharge. Orogastric tubing and gastric trocarization are associated with low complication and high success rates. Either technique is an acceptable method for gastric decompression in dogs with gastric dilatation-volvulus. © 2013 British Small Animal Veterinary Association.

  16. Bubble formation after a 20-m dive: deep-stop vs. shallow-stop decompression profiles

    NARCIS (Netherlands)

    Schellart, Nico A. M.; Corstius, Jan-Jaap Brandt; Germonpré, Peter; Sterk, Wouter


    OBJECTIVES: It is claimed that performing a "deep stop," a stop at about half of maximal diving depth (MDD), can reduce the amount of detectable precordial bubbles after the dive and may thus diminish the risk of decompression sickness. In order to ascertain whether this reduction is caused by the

  17. Exogenous application of platelet-leukocyte gel during open subacromial decompression contributes to improved patient outcome

    NARCIS (Netherlands)

    Everts, P. A.; Devilee, R. J. J.; Mahoney, C. Brown; van Erp, A.; Oosterbos, C. J. M.; Stellenboom, M.; Knape, J. T. A.; van Zundert, A.


    Background: Platelet-leukocyte gel (PLG) is being used during various surgical procedures in an attempt to enhance the healing process. We studied the effects of PLG on postoperative recovery of patients undergoing open subacromial decompression (OSD). Methods: PLG was produced from

  18. Rectus extraocular muscle paths and decompression surgery for Graves orbitopathy: mechanism of motility disturbances

    NARCIS (Netherlands)

    Abràmoff, Michael D.; Kalmann, Rachel; de Graaf, Mieke E. L.; Stilma, Jan S.; Mourits, Maarten P.


    PURPOSE: To study possible causes of motility disturbances that may result from orbital decompression surgery in patients with Graves orbitopathy and especially the role of rectus extraocular muscle paths. METHODS: Sixteen patients with Graves orbitopathy were studied before and 3 to 6 months after

  19. Decoupling of bilayer leaflets under gas supersaturation: nitrogen nanobubbles in a membrane and their implication in decompression sickness (United States)

    Li, Jing; Zhang, Xianren; Cao, Dapeng


    Decompression sickness (also known as diver’s sickness) is a disease that arises from the formation of a bubble inside the body caused by rapid decompression from high atmospheric pressures. However, the nature of pre-existing micronuclei that are proposed for interpreting the formation and growth of the bubble, as well as their very existence, is still highly controversial. In this work, atomistic molecular dynamics simulations are employed to investigate the nucleation of gas bubbles under the condition of nitrogen supersaturation, in the presence of a lipid bilayer and lipid micelle representing other macromolecules with a smaller hydrophobic region. Our simulation results demonstrate that by crossing a small energy barrier, excess nitrogen molecules can enter the lipid bilayer nearly spontaneously, for which the hydrophobic core serves as a potential well for gas enrichment. At a rather low nitrogen supersaturation, gas molecules in the membrane are dispersed in the hydrophobic region of the bilayer, with a slight increase in membrane thickness. But as the level of gas supersaturation reaches a threshold, the accumulation of N2 molecules in the bilayer center causes the two leaflets to be decoupled and the formation of nanobubbles. Therefore, we propose a nucleation mechanism for bubble formation in a supersaturated solution of inert gas: a cell membrane acts as a potential well for gas enrichment, being an ideal location for forming nanobubbles that induce membrane damage at a high level of gas supersaturation. As opposed to previous models, the new mechanism involves forming gas nuclei in a very low-tension hydrophobic environment, and thus a rather low energy barrier is required and pre-existing bubble micronuclei are not needed.

  20. Chest wall thickness and decompression failure: A systematic review and meta-analysis comparing anatomic locations in needle thoracostomy. (United States)

    Laan, Danuel V; Vu, Trang Diem N; Thiels, Cornelius A; Pandian, T K; Schiller, Henry J; Murad, M Hassan; Aho, Johnathon M


    Current Advanced Trauma Life Support guidelines recommend decompression for thoracic tension physiology using a 5-cm angiocatheter at the second intercostal space (ICS) on the midclavicular line (MCL). High failure rates occur. Through systematic review and meta-analysis, we aimed to determine the chest wall thickness (CWT) of the 2nd ICS-MCL, the 4th/5th ICS at the anterior axillary line (AAL), the 4th/5th ICS mid axillary line (MAL) and needle thoracostomy failure rates using the currently recommended 5-cm angiocatheter. A comprehensive search of several databases from their inception to July 24, 2014 was conducted. The search was limited to the English language, and all study populations were included. Studies were appraised by two independent reviewers according to a priori defined PRISMA inclusion and exclusion criteria. Continuous outcomes (CWT) were evaluated using weighted mean difference and binary outcomes (failure with 5-cm needle) were assessed using incidence rate. Outcomes were pooled using the random-effects model. The search resulted in 34,652 studies of which 15 were included for CWT analysis, 13 for NT effectiveness. Mean CWT was 42.79 mm (95% CI, 38.78-46.81) at 2nd ICS-MCL, 39.85 mm (95% CI, 28.70-51.00) at MAL, and 34.33 mm (95% CI, 28.20-40.47) at AAL (P=.08). Mean failure rate was 38% (95% CI, 24-54) at 2nd ICS-MCL, 31% (95% CI, 10-64) at MAL, and 13% (95% CI, 8-22) at AAL (P=.01). Evidence from observational studies suggests that the 4th/5th ICS-AAL has the lowest predicted failure rate of needle decompression in multiple populations. Level 3 SR/MA with up to two negative criteria. Therapeutic. Copyright © 2015 Elsevier Ltd. All rights reserved.

  1. Seizure-Onset Mapping Based on Time-Variant Multivariate Functional Connectivity Analysis of High-Dimensional Intracranial EEG: A Kalman Filter Approach. (United States)

    Lie, Octavian V; van Mierlo, Pieter


    The visual interpretation of intracranial EEG (iEEG) is the standard method used in complex epilepsy surgery cases to map the regions of seizure onset targeted for resection. Still, visual iEEG analysis is labor-intensive and biased due to interpreter dependency. Multivariate parametric functional connectivity measures using adaptive autoregressive (AR) modeling of the iEEG signals based on the Kalman filter algorithm have been used successfully to localize the electrographic seizure onsets. Due to their high computational cost, these methods have been applied to a limited number of iEEG time-series (Kalman filter implementations, a well-known multivariate adaptive AR model (Arnold et al. 1998) and a simplified, computationally efficient derivation of it, for their potential application to connectivity analysis of high-dimensional (up to 192 channels) iEEG data. When used on simulated seizures together with a multivariate connectivity estimator, the partial directed coherence, the two AR models were compared for their ability to reconstitute the designed seizure signal connections from noisy data. Next, focal seizures from iEEG recordings (73-113 channels) in three patients rendered seizure-free after surgery were mapped with the outdegree, a graph-theory index of outward directed connectivity. Simulation results indicated high levels of mapping accuracy for the two models in the presence of low-to-moderate noise cross-correlation. Accordingly, both AR models correctly mapped the real seizure onset to the resection volume. This study supports the possibility of conducting fully data-driven multivariate connectivity estimations on high-dimensional iEEG datasets using the Kalman filter approach.

  2. Does Early Decompressive Craniectomy Improve Outcome? Experience from an Active UK Recruiter Centre

    Directory of Open Access Journals (Sweden)

    E. García Vicente


    Full Text Available Introduction. The results of the recent DECRA study suggest that although craniectomy decreases ICP and ICU length of stay, it is also associated with worst outcomes. Our experience, illustrated by these two striking cases, supports that early decompressive craniectomy may significantly improve the outcome in selected patients. Case Reports. The first patient, a 20-year-old man who suffered severe brain contusion and subarachnoid haemorrhage after a fall downstairs, with refractory ICP of 35 mmHg, despite maximal medical therapy, eventually underwent decompressive craniectomy. After 18 days in intensive care, he was discharged for rehabilitation. The second patient, a 23-year-old man was found at the scene of a road accident with a GCS of 3 and fixed, dilated pupils who underwent extensive unilateral decompressive craniectomy for refractory intracranial hypertension. After three weeks of cooling, paralysis, and neuroprotection, he eventually left ICU for rehabilitation. Outcomes. Four months after leaving ICU, the first patient abseiled 40 m down the main building of St. Mary’s Hospital to raise money for the Trauma Unit. He has returned to part-time work. The second patient, was decannulated less than a month later and made a full cognitive recovery. A year later, with a titanium skull prosthesis, he is back to part-time work and to playing football. Conclusions. Despite the conclusions of the DECRA study, our experience of the use of early decompressive craniectomy has been associated with outstanding outcomes. We are currently actively recruiting patients into the RESCUEicp trial and have high hopes that it will clarify the role of the decompressive craniectomy in traumatic brain injury and whether it effectively improves outcomes.

  3. Surgical outcome after decompressive craniectomy in patients with extensive cerebral infarction

    International Nuclear Information System (INIS)

    Otani, Naoki; Takasato, Yoshio; Masaoka, Hiroyuki


    Extensive cerebral hemispheric infarction is a devastating condition leading to early death in nearly 80% of cases due to the rapid rise of intracranial pressure in spite of maximum medical treatment for brain edema and swelling. Recently, decompressive craniectomy has been reevaluated to prevent the brain herniation caused by extensive hemispheric cerebral infarction. We studied the surgical results after decompressive craniectomy for extensive cerebral infarction. Between December 1997 and August 2006, 13 consecutive patients (7 males and 6 females aged from 39 to 73 with a mean age of 59 years) with massive cerebral infarction of internal carotid (IC) (11 patients) and middle cerebral artery (MCA) (2 patients) territory were treated with decompressive craniectomy and dural plasty. Five patients had a left-sided stroke with severe aphasia. The cardioembolic source of stroke was seen in 5 patients. Surgery was performed at the point of neurological deterioration, anisocoria, and effacement of perimesencephalic cistern on CT findings. The mean time between stroke onset and surgery was 39.8 hr and ranged from 13 to 102 hr. Glasgow outcome scale (GOS) on discharge was moderately disabled (MD) 1, severe disabled (SD) 5, vegetative state (VS) 1, and dead (D) 3 (mortality rate 30.8%). Severe pneumoniae were the causes of death. All survivors underwent cranioplasty and were transferred with the aim of rehabilitation. In this study, we showed that the decompressive craniectomy reduced mortality after extensive cerebral infarction. However, the functional outcome and level of independence are poor. It seems that the early decompressive craniectomy should be aggressively performed for extensive cerebral infarction before neurological deterioration such as worsening of consciousness disturbance or pupil abnormalities. Further investigations will be needed to clarify the surgical indications, timing, and functional outcomes. (author)

  4. Does decompression of odontogenic cysts and cystlike lesions change the histologic diagnosis? (United States)

    Schlieve, Thomas; Miloro, Michael; Kolokythas, Antonia


    The purpose of this study was to report the histopathologic findings after postdecompression definitive treatment of odontogenic cystlike lesions and determine whether the diagnosis was consistent with the pretreatment diagnosis, thereby answering the clinical question: does decompression change the histologic diagnosis? The authors implemented a retrospective cohort study from a sample of patients diagnosed with a benign odontogenic cystlike lesion and who underwent decompression followed by definitive surgery as part of their treatment. The predictor variable was treatment by decompression and the dependent variable was change in histologic diagnosis. Age, gender, and lesion location were included as variables. The χ(2) test was used for statistical analysis of the categorical data and P values less than .05 were considered statistically significant. Twenty-five cysts and cystlike lesions in 25 patients were treated with decompression followed by enucleation and curettage. The mean age was 34 years (range, 13 to 80 yr) and 56% (14) were male patients. Lesions were located in the mandible in 76% (19 of 25) of patients. Postdecompression histologic examination at the time of definitive surgical treatment was consistent with the preoperative biopsy diagnosis in 91% (10 of 11) of keratocystic odontogenic tumors, 67% (2 of 3) of glandular odontogenic cysts, 75% (3 of 4) of dentigerous cysts, and 100% (7 of 7) of cystic ameloblastomas. The histologic diagnosis at time of definitive treatment by enucleation and curettage is consistent with the predecompression diagnosis. Therefore, all lesions should be definitively treated after decompression based on the initial lesion diagnosis, with all patients placed on appropriate follow-up protocols. Copyright © 2014 American Association of Oral and Maxillofacial Surgeons. All rights reserved.

  5. ORACLE Stroke Study: Opinion Regarding Acceptable Outcome Following Decompressive Hemicraniectomy for Ischemic Stroke. (United States)

    Honeybul, Stephen; Ho, Kwok M; Blacker, David W


    There continues to be considerable interest in the use of decompressive hemicraniectomy in the management of malignant cerebral artery infarction; however, concerns remain about long-term outcome. To assess opinion on consent and acceptable outcome among a wide range of healthcare workers. Seven hundred seventy-three healthcare workers at the 2 major public neurosurgical centers in Western Australia participated. Participants were asked to record their opinion on consent and acceptable outcome based on the modified Rankin Score (mRS). The evidence for clinical efficacy of the procedure was presented, and participants were then asked to reconsider their initial responses. Of the 773 participants included in the study, 407 (52.7%) initially felt that they would provide consent for a decompressive craniectomy as a lifesaving procedure, but only a minority of them considered an mRS score of 4 or 5 an acceptable outcome (for mRS score ≤4, n = 67, 8.7%; for mRS score = 4, n = 57, 7.4%). After the introduction of the concept of the disability paradox and the evidence for the clinical efficacy of decompressive craniectomy, more participants were unwilling to accept decompressive craniectomy (18.1% vs 37.8%), but at the same time, more were willing to accept an mRS score ≤4 as an acceptable outcome (for mRS score ≤4, n = 92, 11.9%; for mRS score = 4, n = 79, 10.2%). Most participants felt survival with dependency to be unacceptable. However, many would be willing to provide consent for surgery in the hopes that they may survive with some degree of independence. DESTINY, Decompressive Surgery for the Treatment of Malignant Infarction of the Middle Cerebral ArterymRS, modified Rankin Scale.

  6. Facet Effusion without Radiographic Instability Has No Effect on the Outcome of Minimally Invasive Decompression Surgery. (United States)

    Tamai, Koji; Kato, Minori; Konishi, Sadahiko; Matsumura, Akira; Hayashi, Kazunori; Nakamura, Hiroaki


    Retrospective cohort study. Lumbar segmental instability is a key factor determining whether decompression alone or decompression and fusion surgery is required to treat lumbar spinal stenosis (LSS). Some recent reports have suggested that facet joint effusion is correlated with spinal segmental instability. The aim of this study is to report the effect of facet effusion without radiographic segmental instability on the outcome of less-invasive decompression surgery for LSS. Seventy-nine patients with LSS (32 women, mean age: 69.1 ± 9.1 years) who had no segmental instability on dynamic radiographs before undergoing L4-L5 microsurgical decompression and who were followed for at least 2 years postoperatively were analyzed. They were divided into three groups on the basis of the existence and size of L4-L5 facet effusion using preoperative magnetic resonance imaging: grade 0 had no effusion ( n  = 31), grade 1 had measurable effusion ( n  = 35), and grade 2 had large effusion ( n  = 13). Japanese Orthopedics Association (JOA) score, visual analog scale (VAS), and the Short-Form (SF)-36 scores were recorded preoperatively and 12 and 24 months postoperatively. JOA score; VAS of low back pain, leg pain, and numbness; and SF-36 (physical component summary and mental component summary) scores did not differ significantly between the three groups in every terms ( p  = 0.921, 0.996, 0.950, 0.693, 0.374, 0.304, and 0.624, respectively, at final follow-up). In the absence of radiographic instability, facet joint effusion has no effect on the outcome of less-invasive decompression surgery.

  7. Mortality Rates After Emergent Posterior Fossa Decompression for Ischemic or Hemorrhagic Stroke in Older Patients. (United States)

    Puffer, Ross C; Graffeo, Christopher; Rabinstein, Alejandro; Van Gompel, Jamie J


    Cerebellar stroke causes major morbidity in the aging population. Guidelines from the American Stroke Association recommend emergent decompression in patients who have brainstem compression, hydrocephalus, or clinical deterioration. The objective of this study was to determine 30-day and 1-year mortality rates in patients >60 years old undergoing emergent posterior fossa decompression. Surgical records identified all patients >60 years old who underwent emergent posterior fossa decompression. Mortality rates were calculated at 30 days and 1 year postoperatively, and these rates were compared with patient and procedure characteristics. During 2000-2014, 34 emergent posterior fossa decompressions were performed in patients >60 years old. Mortality rates at 30 days were 0%, 33%, and 25% for age deciles 60-69 years, 70-79 years, and ≥80 years. Increasing age (alive at 30 days 75.2 years ± 1.7 vs. deceased 81.1 years ± 1.7, P = 0.01) and smaller craniectomy dimensions were associated with 30-day mortality. Mortality rates at 1 year were 0%, 50%, and 67% for age deciles 60-69 years, 70-79 years, and ≥80 years. Increasing age was significantly associated with mortality at 1 year (alive at 1 year 72.3 years ± 2.0 vs. deceased 81.1 years ± 1.2, P mortality. Age was independent of admission Glasgow Coma Scale score as a predictor of mortality at 30 days, 90 days, and 1 year postoperatively. Increasing age and smaller craniectomy size were significantly associated with mortality in patients undergoing emergent posterior fossa decompression. Among patients ≥80 years old, one-quarter were dead within 1 month of the operation, and more than two-thirds were dead within 1 year. Copyright © 2016 Elsevier Inc. All rights reserved.

  8. Decompression sickness in breath-hold diving, and its probable connection to the growth and dissolution of small arterial gas emboli. (United States)

    Goldman, Saul; Solano-Altamirano, J M


    We solved the Laplace equation for the radius of an arterial gas embolism (AGE), during and after breath-hold diving. We used a simple three-region diffusion model for the AGE, and applied our results to two types of breath-hold dives: single, very deep competitive-level dives and repetitive shallower breath-hold dives similar to those carried out by indigenous commercial pearl divers in the South Pacific. Because of the effect of surface tension, AGEs tend to dissolve in arterial blood when arteries remote from supersaturated tissue. However if, before fully dissolving, they reach the capillary beds that perfuse the brain and the inner ear, they may become inflated with inert gas that is transferred into them from these contiguous temporarily supersaturated tissues. By using simple kinetic models of cerebral and inner ear tissue, the nitrogen tissue partial pressures during and after the dive(s) were determined. These were used to theoretically calculate AGE growth and dissolution curves for AGEs lodged in capillaries of the brain and inner ear. From these curves it was found that both cerebral and inner ear decompression sickness are expected to occur occasionally in single competitive-level dives. It was also determined from these curves that for the commercial repetitive dives considered, the duration of the surface interval (the time interval separating individual repetitive dives from one another) was a key determinant, as to whether inner ear and/or cerebral decompression sickness arose. Our predictions both for single competitive-level and repetitive commercial breath-hold diving were consistent with what is known about the incidence of cerebral and inner ear decompression sickness in these forms of diving. Copyright © 2015 Elsevier Inc. All rights reserved.

  9. Early biliary decompression versus conservative treatment in acute biliary pancreatitis (APEC trial): study protocol for a randomized controlled trial

    NARCIS (Netherlands)

    Schepers, N.J.; Bakker, O.J.; Besselink, M.G.; Bollen, T.L.; Dijkgraaf, M.G.; Eijck, C.H. van; Fockens, P.; Geenen, E.J. van; Grinsven, J. van; Hallensleben, N.D.; Hansen, B.E.; Santvoort, H.C. van; Timmer, R.; Anten, M.P.; Bolwerk, C.J.; Delft, F. von; Dullemen, H.M. van; Erkelens, G.W.; Hooft, J.E. van; Laheij, R.; Hulst, R.W. van der; Jansen, J.M.; Kubben, F.J.; Kuiken, S.D.; Perk, L.E.; Ridder, R.J. de; Rijk, M.C. de; Romkens, T.E.; Schoon, E.J.; Schwartz, M.P.; Spanier, B.W.; Tan, A.C.; Thijs, W.J.; Venneman, N.G.; Vleggaar, F.P.; Vrie, W. van de; Witteman, B.J.; Gooszen, H.G.; Bruno, M.J.


    BACKGROUND: Acute pancreatitis is mostly caused by gallstones or sludge. Early decompression of the biliary tree by endoscopic retrograde cholangiography (ERC) with sphincterotomy may improve outcome in these patients. Whereas current guidelines recommend early ERC in patients with concomitant

  10. Early biliary decompression versus conservative treatment in acute biliary pancreatitis (APEC trial): Study protocol for a randomized controlled trial

    NARCIS (Netherlands)

    N.J. Schepers (Nicolien); O.J. Bakker (Olaf ); M.G. Besselink (Marc); T.L. Bollen (Thomas); M.G.W. Dijkgraaf (Marcel); C.H.J. van Eijck (Casper); P. Fockens (Paul); E-J.M. Geenen (Erwin-Jan); J. van Grinsven (Janneke); N.D.L. Hallensleben (Nora D.L.); B.E. Hansen (Bettina); H.C. van Santvoort (Hjalmar); R. Timmer (Robin); M.-P.G.F. Anten (Marie-Paule G.F.); C.L. Bolwerk (Clemens); F. van Delft (Foke); H.M. van Dullemen (Hendrik); G.W. Erkelens (G.Willemien); J.E. van Hooft (Jeanin); C. Laheij (Claudia); R.W.M. van der Hulst (René); J.M. Jansen (Jeroen); F.J. Kubben; S.D. Kuiken (Sjoerd D.); L.E. Perk (Lars E.); R. de Ridder (Rogier); M.C.M. Rijk; T.E.H. Römkens; E.J. Schoon (Erik); M.P. Schwartz (Matthijs P.); B.W.M. Spanier (Marcel); A.C. Tan (Adriaan); W.J. Thijs; N.G. Venneman (Niels); F.P. Vleggaar (Frank); W. van de Vrie (Wim); B.J.M. Witteman (Ben); H.G. Gooszen (Hein); M.J. Bruno (Marco)


    textabstractBackground: Acute pancreatitis is mostly caused by gallstones or sludge. Early decompression of the biliary tree by endoscopic retrograde cholangiography (ERC) with sphincterotomy may improve outcome in these patients. Whereas current guidelines recommend early ERC in patients with

  11. Successful Treatment of Early Talar Osteonecrosis by Core Decompression Combined with Intraosseous Stem Cell Injection: A Case Report. (United States)

    Nevalainen, Mika T; Repo, Jussi P; Pesola, Maija; Nyrhinen, Jukka P


    Osteonecrosis of the talus is a fairly rare condition. Many predisposing factors have been identified including previous trauma, use of corticosteroids, alcoholism, and smoking. As a gold standard, magnetic resonance imaging (MRI) is the most sensitive and specific diagnostic examination to detect osteonecrosis. While many treatment options for talar osteonecrosis exist, core decompression is suggested on young patients with good outcome results. More recently, intraosseous stem cell and platelet-rich plasma (PRP) injection has been added to the core decompression procedure. We report a successful treatment of early talar osteonecrosis ARCO I (Association Research Circulation Osseous) by core decompression combined with stem cell and PRP injection. On 3-month and 15-month follow-up, MRI showed complete resolution of the osteonecrotic changes together with clinical improvement. This modified technique is a viable treatment option for early talar osteonecrosis. Nevertheless, future prospects should include a study comparing this combined technique with plain core decompression.

  12. Early biliary decompression versus conservative treatment in acute biliary pancreatitis (APEC trial) : Study protocol for a randomized controlled trial

    NARCIS (Netherlands)

    Schepers, Nicolien J.; Bakker, Olaf J.; Besselink, Marc G H; Bollen, Thomas L.; Dijkgraaf, Marcel G W; van Eijck, Casper H J; Fockens, Paul; van Geenen, Erwin J M; van Grinsven, Janneke; Hallensleben, Nora D L; Hansen, Bettina E.; van Santvoort, Hjalmar C.; Timmer, Robin; Anten, Marie Paule G F; Bolwerk, Clemens J M; van Delft, Foke; van Dullemen, Hendrik M.; Erkelens, G. Willemien; van Hooft, Jeanin E.; Laheij, Robert; van der Hulst, René W M; Jansen, Jeroen M.; Kubben, Frank J G M; Kuiken, Sjoerd D.; Perk, Lars E.; de Ridder, Rogier J J; Rijk, Marno C M; Römkens, Tessa E H; Schoon, Erik J.; Schwartz, Matthijs P.; Spanier, B. W Marcel; Tan, Adriaan C I T L; Thijs, Willem J.; Venneman, Niels G.; Vleggaar, Frank P.; van de Vrie, Wim; Witteman, Ben J.; Gooszen, Hein G.; Bruno, Marco J.


    Background: Acute pancreatitis is mostly caused by gallstones or sludge. Early decompression of the biliary tree by endoscopic retrograde cholangiography (ERC) with sphincterotomy may improve outcome in these patients. Whereas current guidelines recommend early ERC in patients with concomitant

  13. Operative Technique and Clinical Outcome in Endoscopic Core Decompression of Osteochondral Lesions of the Talus: A Pilot Study


    Beck, Sascha; Cla?en, Tim; Haversath, Marcel; J?ger, Marcus; Landgraeber, Stefan


    Background Revitalizing the necrotic subchondral bone and preserving the intact cartilage layer by retrograde drilling is the preferred option for treatment of undetached osteochondral lesions of the talus (OLT). We assessed the effectiveness of Endoscopic Core Decompression (ECD) in treatment of OLT. Material/Methods Seven patients with an undetached OLT of the medial talar dome underwent surgical treatment using an arthroscopically-guided transtalar drill meatus for core decompression of th...

  14. Persistent sciatica induced by quadratus femoris muscle tear and treated by surgical decompression: a case report

    Directory of Open Access Journals (Sweden)

    Tzanakakis George


    Full Text Available Abstract Introduction Quadratus femoris tear is an uncommon injury, which is only rarely reported in the literature. In the majority of cases the correct diagnosis is delayed due to non-specific symptoms and signs. A magnetic resonance imaging scan is crucial in the differential diagnosis since injuries to contiguous soft tissues may present with similar symptoms. Presentation with sciatica is not reported in the few cases existing in the English literature and the reported treatment has always been conservative. Case presentation We report here on a case of quadratus femoris tear in a 22-year-old Greek woman who presented with persistent sciatica. She was unresponsive to conservative measures and so was treated with surgical decompression. Conclusion The correct diagnosis of quadratus muscle tear is a challenge for physicians. The treatment is usually conservative, but in cases of persistent sciatica surgical decompression is an alternative option.

  15. Decompressive Abdominal Laparotomy for Abdominal Compartment Syndrome in an Unengrafted Bone Marrow Recipient with Septic Shock

    Directory of Open Access Journals (Sweden)

    Derrick J. N. Dauplaise


    Full Text Available Objective. To describe a profoundly immunocompromised (panleukopenia child with septic shock who developed abdominal compartment syndrome (ACS and was successfully treated with surgical decompression. Design. Individual case report. Setting. Pediatric intensive care unit of a tertiary children's hospital. Patient. A 32-month-old male with Fanconi anemia who underwent bone marrow transplantation (BMT 5 days prior to developing septic shock secondary to Streptococcus viridans and Escherichia coli ACS developed after massive fluid resuscitation, leading to cardiopulmonary instability. Interventions. Emergent surgical bedside laparotomy and silo placement. Measurements and Main Results. The patient's cardiopulmonary status stabilized after decompressive laparotomy. The abdomen was closed and the patient survived to hospital discharge without cardiac, respiratory, or renal dysfunction. Conclusions. The use of laparotomy and silo placement in an unengrafted BMT patient with ACS and septic shock did not result in additional complications. Surgical intervention for ACS is a reasonable option for high risk, profoundly immunocompromised patients.

  16. [Successful microvascular decompression of the medulla oblongata for a case with respiratory failure: case report]. (United States)

    Koguchi, Motofumi; Nakahara, Yukiko; Kawashima, Masatou; Takase, Yukinori; Matsushima, Toshio


    We report a case of the medulla oblongata syndrome successfully treated by microvascular decompression surgery. The patient was a 75-year-old woman and had been suffering from gradual progressive dyspnea since July, 2009. Two month later, intubation and medial ventilator treatments were began because of severe respiratory problems. The central respiratory problems were considered in extensive testing by the physician. The head MR imaging showed that the left vertebral artery had markedly compressed the medulla oblongata. We thought that her respiratory problems were associated with this vertebral artery compression of the medulla oblongata. We performed the microvascular decompression surgery by left trans-condylar fossa approach. Her hypoventilation graduately improved after the surgery and she needed neither ventilator nor oxygen in several months. She is able to perform daily activities by herself. We report the case, and discuss the cause of respiratory problems especially by compression of the medulla oblongata.

  17. MRI appearance of femoral head osteonecrosis following core decompression and bone grafting

    Energy Technology Data Exchange (ETDEWEB)

    Chan, T W; Dalinka, M K; Kressel, H Y [Pennsylvania Univ. Hospital, Philadelphia, PA (USA). Dept. of Radiology; Steinberg, M E [Pennsylvania Univ. Hospital, Philadelphia, PA (USA). Dept. of Orthopedic Surgery


    We used magnetic resonance imaging (MRI) to evaluate retrospectively 32 hips with avascular necrosis of the femoral head before and after core decompression and bone grafting. At a median follow-up time of 15 months, 4 of 9 large lesions had undergone femoral head collapse; 2 small lesions had decreased in size; and 14 small, 6 moderate, and 5 large lesions were unchanged. One hip with biopsy-proven avascular necrosis had diffuse marrow edema which resolved after surgery. The signal pattern within the lesions was analyzed in 17 hips. MRI can demonstrate changes in size and signal characteristics as well as femoral head collapse after core decompression and bone grafting. Changes in the surrounding marrow signal, including resolution of marrow edema and reconversion from fatty to hemopoietic marrow, can also be detected. (orig./GDG).

  18. Avascular bone necrosis: MR imaging findings before and after core decompression

    International Nuclear Information System (INIS)

    Adam, G.; Keulers, P.; Forst, J.; Neuerburg, J.; Kilbinger, M.; Guenther, R.W.


    17 patients with avascular epiphyseal necrosis were examined by MRI using T 1 -weighted spin echo sequences before and after gadopentetate dimeglumine application, T 2 -weighted spin echo sequences and in some patients with fat-saturated 2D gradient echo sequences up to 22 months after core decompression. All patients but one recovered from symptoms after core decompression. Although the signal morphology of the necrotic area remained unchanged in the majority of the cases, a decrease of the joint effusion was observed as well as an ongoing signal increase after gadopentetate dimeglumine application. The last examinations displayed similar signal characteristics as on the preoperative scans; however, a reduction of the necrotic zone became evident. (orig./MG) [de

  19. Developments in time-resolved high pressure x-ray diffraction using rapid compression and decompression

    International Nuclear Information System (INIS)

    Smith, Jesse S.; Sinogeikin, Stanislav V.; Lin, Chuanlong; Rod, Eric; Bai, Ligang; Shen, Guoyin


    Complementary advances in high pressure research apparatus and techniques make it possible to carry out time-resolved high pressure research using what would customarily be considered static high pressure apparatus. This work specifically explores time-resolved high pressure x-ray diffraction with rapid compression and/or decompression of a sample in a diamond anvil cell. Key aspects of the synchrotron beamline and ancillary equipment are presented, including source considerations, rapid (de)compression apparatus, high frequency imaging detectors, and software suitable for processing large volumes of data. A number of examples are presented, including fast equation of state measurements, compression rate dependent synthesis of metastable states in silicon and germanium, and ultrahigh compression rates using a piezoelectric driven diamond anvil cell

  20. Evaluation of Outcome of Posterior Decompression and Instrumented Fusion in Lumbar and Lumbosacral Tuberculosis. (United States)

    Jain, Akshay; Jain, Ravikant; Kiyawat, Vivek


    For surgical treatment of lumbar and lumbosacral tuberculosis, the anterior approach has been the most popular approach because it allows direct access to the infected tissue, thereby providing good decompression. However, anterior fixation is not strong, and graft failure and loss of correction are frequent complications. The posterior approach allows circumferential decompression of neural elements along with three-column fixation attained via pedicle screws by the same approach. The purpose of this study was to evaluate the outcome (functional, neurological, and radiological) in patients with lumbar and lumbosacral tuberculosis operated through the posterior approach. Twenty-eight patients were diagnosed with tuberculosis of the lumbar and lumbosacral region from August 2012 to August 2013. Of these, 13 patients had progressive neurological deterioration or increasing back pain despite conservative measures and underwent posterior decompression and pedicle screw fixation with posterolateral fusion. Antitubercular therapy was given till signs of radiological healing were evident (9 to 16 months). Functional outcome (visual analogue scale [VAS] score for back pain), neurological recovery (Frankel grading), and radiological improvement were evaluated preoperatively, immediately postoperatively and 3 months, 6 months, and 1 year postoperatively. The mean VAS score for back pain improved from 7.89 (range, 9 to 7) preoperatively to 2.2 (range, 3 to 1) at 1-year follow-up. Frankel grading was grade B in 3, grade C in 7, and grade D in 3 patients preoperatively, which improved to grade D in 7 and grade E in 6 patients at the last follow-up. Radiological healing was evident in the form of reappearance of trabeculae formation, resolution of pus, fatty marrow replacement, and bony fusion in all patients. The mean correction of segmental kyphosis was 9.85° postoperatively. The mean loss of correction at final follow-up was 3.15°. Posterior decompression with instrumented

  1. Documentation for the USAF School of Aerospace Medicine Altitude Decompression Sickness Research Database (United States)


    identification during some database operations and that "t" and other such identifiers are dropped in the following headings to allow easier reading of the...chamber floor, the subject cranks at 24 rpm with 20-Watt resistance as read on the 50 rpm ergometer scale, switching hands each 2 pedal revolutions...Emboli DCS Decompression Sickness EKG /ECG Electrokardiograph (German), electrocardiograph (English) EVA Extravehicular Activity ICD Informed Consent

  2. The Pathophysiology of Decompression Sickness and the Effects of Doppler Detectable Bubbles. (United States)


    workers (Harvey, 1951a and 1951b) and Blinks, Twitty and Whiteker (1951) show that muscular activity was a 23 ~I. predisposing factor to the formation of...Hills, 1966), the mechanism of action is somewhat specific (neural distension ); but for those theories utilizing circulation and/or intravascular...highly perfused non- muscular tissue, such as kidney, forms a gas phase following decompression, Doppler perivascular cuff probes were surgically placed on

  3. Timing of Decompression in Patients With Acute Spinal Cord Injury: A Systematic Review


    Wilson, Jefferson R.; Tetreault, Lindsay A.; Kwon, Brian K.; Arnold, Paul M.; Mroz, Thomas E.; Shaffrey, Christopher; Harrop, James S.; Chapman, Jens R.; Casha, Steve; Skelly, Andrea C.; Holmer, Haley K.; Brodt, Erika D.; Fehlings, Michael G.


    Study Design: Systematic review. Objective: To conduct a systematic review and synthesis of the literature to assess the comparative effectiveness, safety, and cost-effectiveness of early (≤24 hours) versus late decompression (>24 hours) in adults with acute spinal cord injury (SCI). Methods: A systematic search was conducted of Medline, EMBASE, the Cochrane Collaboration Library, and Google Scholar to identify studies published through November 6, 2014. Studies published in any language, in ...

  4. Patent Foramen Ovale as a Risk Factor for Altitude Decompression Illness (United States)


    Medical Issues in Hypo-and Hyperbaric Conditions [les Questions medicales a caractere oprationel liees aux conditions hypobares ou hyperbares ] To order the...on "Operational Medical Issues in Hypo- and Hyperbaric Conditions ", held in Toronto, Canada, 16-19 October 2000, and published in RTO MP-062. 3-2...Space Environ Med 1996; 67: 1092-6. Powell MR, Norfleet WT, Kumar KV, Butler BD. Patent foramen ovale and hypobaric decompression. Aviat Space Environ

  5. Effect of decompressive hemicraniectomy on mortality of malignant middle cerebral artery infarction


    Bahram Aminmansour; Majeed Rezvany; Davood Sharifi; Hamidreza Shemshaki


    Background: Increasing intracranial pressure (ICP) is one of the leading causes of mortality in patients with malignant infarction of the middle cerebral artery (MCA). We prospectively evaluated patients with MCA infarction for one month survival after decompressive hemicraniectomy. Methods: This study was conducted at Alzahra University Hospital, Isfahan (Iran). Twenty patients with infarction in total MCA distribution area, resulting in midline shift of brain tissue for greater than 5mm...

  6. Management of sinonasal complications after endoscopic orbital decompression for Graves' orbitopathy. (United States)

    Antisdel, Jastin L; Gumber, Divya; Holmes, Janalee; Sindwani, Raj


    Endoscopic orbital decompression (EnOD) has proven to be safe and effective for the treatment of Graves' orbitopathy; however, complications do occur. Although the literature focuses on orbital complications, sinonasal complications including postobstructive sinusitis, hemorrhage, and cerebrospinal fluid (CSF) leak can also be challenging to manage. This study examines the incidence and management of sinonasal complications in these patients. Retrospective review. Clinical data, surgical findings, and postoperative outcomes were reviewed of patients who underwent EnOD for Graves' disease between March 2004 and November 2010. The incidence and management of postoperative sinonasal complications requiring an intervention were examined. The study group consisted of 50 consecutive patients (86 decompression procedures): 11 males and 39 females with an average age of 48.6 years (SD = 12.9). Incidence of significant sinonasal complications was 3.5% (5/86): with one patient experiencing postoperative hemorrhage requiring operative management, three patients with postoperative obstructive sinusitis, and one patient with nasal obstruction secondary to nasal adhesions that required lysis. The maxillary sinus was the most commonly involved and was managed using the mega-antrostomy technique. In the case of frontal sinusitis, an endoscopic transaxillary approach was utilized to avoid injury to decompressed orbital contents. All complications were successfully managed without sequelae. Sinonasal complications following EnOD are uncommon. In the setting of a decompressed orbit, even routine types of postoperative issues can be challenging and require additional considerations. Successful management of postoperative sinusitis related to outflow obstruction may require more extensive approaches and novel techniques. Copyright © 2013 The American Laryngological, Rhinological and Otological Society, Inc.

  7. The Belgian End of Mission Transition Period: Lessons Learned from Third Location Decompression after Operational Deployment (United States)


    Third Location Decompression after Operational Deployment 11 - 2 RTO-MP-HFM-205 programs is based upon the literature on combat motivation ...exposure to normal leisure activities and tourism . Massage is another interesting element in the French program. Each soldier receives at least one... gastronomy ; during the French TLD, soldiers were allowed to drink wine or beer with their meal starting at 7pm and bars closed at 1am ultimately. Alcohol

  8. Early Autologous Cranioplasty after Decompressive Hemi-Craniectomy for Severe Traumatic Brain Injury

    International Nuclear Information System (INIS)

    Qasmi, S. A.; Ghaffar, A.; Hussain, Z.; Mushtaq, J.


    Objective: To evaluate the outcome of early replacement of autologous bone flap for decompressive hemicraniectomy in severe traumatic brain injury patients. Methods: The observational cross-sectional prospective study was conducted at the Neurosurgical Unit of the Combined Military Hospital, Rawalpindi, Pakistan, from July 2011, to June 2014, and comprised patients who underwent cranioplasty after decompressive hemicraniectomy for trauma. Patients over 20 years of age and of either gender were included. Cranioplasty was timed in all these patients using native bone flap preserved in the abdominal wall after decompressive craniectomy. Parameters recorded were mortality, wound infection, subdural collection, wound dehiscence, ventriculomegaly, bone resorption, cosmetic deformity and neurological outcome. SPSS 17 was used for data analysis. Results: Of the 30 patients in the study, 28(93.3 percent) were males. The overall mean age was age 32.03±8.01 years (range: 20-48 years). Mean cranioplasty time was 66.2±11.50 days (range: 44-89 days). Major infection necessitating bone flap removal was found in 1(3.33 percent) patient, while minor scalp wound infections, treated with antibiotics and dressings were found in 2(6.66 percent). Cosmetic18 deformity was seen in 3(10 percent). Improved neurological outcome was noted in 21(70 percent) patients; 6(20 percent) survived with a moderate to severe disability and 3(10 percent) remained in a vegetative state. No mortality was found after the procedure. Conclusion: Early autologous bone replacement for decompressive hemicraniectomy in severe traumatic brain injury patients offered cost-effective, acceptable surgical and improve dneurological outcome. (author)

  9. Macrovascular Decompression of the Brainstem and Cranial Nerves: Evolution of an Anteromedial Vertebrobasilar Artery Transposition Technique. (United States)

    Choudhri, Omar; Connolly, Ian D; Lawton, Michael T


    Tortuous and dolichoectatic vertebrobasilar arteries can impinge on the brainstem and cranial nerves to cause compression syndromes. Transposition techniques are often required to decompress the brainstem with dolichoectatic pathology. We describe our evolution of an anteromedial transposition technique and its efficacy in decompressing the brainstem and relieving symptoms. To present the anteromedial vertebrobasilar artery transposition technique for macrovascular decompression of the brainstem and cranial nerves. All patients who underwent vertebrobasilar artery transposition were identified from the prospectively maintained database of the Vascular Neurosurgery service, and their medical records were reviewed retrospectively. The extent of arterial displacement was measured pre- and postoperatively on imaging. Vertebrobasilar arterial transposition and macrovascular decompression was performed in 12 patients. Evolution in technique was characterized by gradual preference for the far-lateral approach, use of a sling technique with muslin wrap, and an anteromedial direction of pull on the vertebrobasilar artery with clip-assisted tethering to the clival dura. With this technique, mean lateral displacement decreased from 6.6 mm in the first half of the series to 3.8 mm in the last half of the series, and mean anterior displacement increased from 0.8 to 2.5 mm, with corresponding increases in satisfaction and relief of symptoms. Compressive dolichoectatic pathology directed laterally into cranial nerves and posteriorly into the brainstem can be corrected with anteromedial transposition towards the clivus. Our technique accomplishes this anteromedial transposition from an inferolateral surgical approach through the vagoaccessory triangle, with sling fixation to clival dura using aneurysm clips. Copyright © 2017 by the Congress of Neurological Surgeons

  10. Patent foramen ovale influences the presentation of decompression illness in SCUBA divers. (United States)

    Liou, Kevin; Wolfers, Darren; Turner, Robert; Bennett, Michael; Allan, Roger; Jepson, Nigel; Cranney, Greg


    Few have examined the influence of patent foramen ovale (PFO) on the phenotype of decompression illness (DCI) in affected divers. A retrospective review of our database was performed for 75 SCUBA divers over a 10-year period. Overall 4,945 bubble studies were performed at our institution during the study period. Divers with DCI were more likely to have positive bubble studies than other indications (pAustralia and New Zealand (CSANZ). Published by Elsevier B.V. All rights reserved.

  11. Total Facial Nerve Decompression for Severe Traumatic Facial Nerve Paralysis: A Review of 10 Cases

    Directory of Open Access Journals (Sweden)

    Sertac Yetiser


    Full Text Available Management of traumatic facial nerve disorders is challenging. Facial nerve decompression is indicated if 90–95% loss of function is seen at the very early period on ENoG or if there is axonal degeneration on EMG lately with no sign of recovery. Middle cranial or translabyrinthine approach is selected depending on hearing. The aim of this study is to present retrospective review of 10 patients with sudden onset complete facial paralysis after trauma who underwent total facial nerve decompression. Operation time after injury is ranging between 16 and105 days. Excitation threshold, supramaximal stimulation, and amplitude on the paralytic side were worse than at least %85 of the healthy side. Six of 11 patients had HBG-II, one patient had HBG-I, 3 patients had HBG-III, and one patient had HBG-IV recovery. Stretch, compression injuries with disruption of the endoneurial tubules undetectable at the time of surgery and lack of timely decompression may be associated with suboptimal results in our series.

  12. Nonaffine deformation under compression and decompression of a flow-stabilized solid (United States)

    Ortiz, Carlos P.; Riehn, Robert; Daniels, Karen E.


    Understanding the particle-scale transition from elastic deformation to plastic flow is central to making predictions about the bulk material properties and response of disordered materials. To address this issue, we perform experiments on flow-stabilized solids composed of micron-scale spheres within a microfluidic channel, in a regime where particle inertia is negligible. Each solid heap exists within a stress field imposed by the flow, and we track the positions of particles in response to single impulses of fluid-driven compression or decompression. We find that the resulting deformation field is well-decomposed into an affine field, with a constant strain profile throughout the solid, and a non-affine field. The magnitude of this non-affine response decays with the distance from the free surface in the long-time limit, suggesting that the distance from jamming plays a significant role in controlling the length scale of plastic flow. Finally, we observe that compressive pulses create more rearrangements than decompressive pulses, an effect that we quantify using the D\\text{min}2 statistic for non-affine motion. Unexpectedly, the time scale for the compression response is shorter than for decompression at the same strain (but unequal pressure), providing insight into the coupling between deformation and cage-breaking.

  13. Resolution of extra-axial collections after decompressive craniectomy for ischemic stroke. (United States)

    Ropper, Alexander E; Nalbach, Stephen V; Lin, Ning; Dunn, Ian F; Gormley, William B


    Extra-axial fluid collections are known consequences of decompressive hemicraniectomy. Studies have examined these collections and their management. We retrospectively reviewed 12 consecutive patients who underwent decompressive hemicraniectomy for the treatment of malignant cerebral edema after infarction and evaluated the evolution, resolution and treatment of post-operative extra-axial fluid collections. All patients underwent standard-sized frontotemporoparietal hemicraniectomy with duraplasty as treatment for medically intractable malignant cerebral edema at an average of 3 days after the stroke (median 2 days). Their 30-day mortality was 25%. Three patients developed some extra-axial fluid collections after craniectomy: two patients developed the collections early in their post-operative course, 3 days and 5 days after the craniectomy. Both experienced spontaneous resolution of the collections without corrective cranioplasty or shunt placement at 34 days and 58 days after surgery. The third patient developed a collection 55 days after the operation related to a subgaleal bacterial infection. In the final analysis, 18% of patients developed extra-axial collections and all resolved spontaneously. The incidence of extra-axial collections after decompressive hemicraniectomy following ischemic stroke was lower in our retrospective series than has been reported by others. The collections resolved spontaneously, suggesting that early anticipatory, corrective treatment with cerebrospinal fluid diversion or cranioplasty may not be warranted. Copyright © 2011 Elsevier Ltd. All rights reserved.

  14. Effect of decompressive hemicraniectomy on mortality of malignant middle cerebral artery infarction

    Directory of Open Access Journals (Sweden)

    Bahram Aminmansour


    Full Text Available Background: Increasing intracranial pressure (ICP is one of the leading causes of mortality in patients with malignant infarction of the middle cerebral artery (MCA. We prospectively evaluated patients with MCA infarction for one month survival after decompressive hemicraniectomy. Methods: This study was conducted at Alzahra University Hospital, Isfahan (Iran. Twenty patients with infarction in total MCA distribution area, resulting in midline shift of brain tissue for greater than 5mm, underwent decompressive hemicraniectomy. Mortality rate was estimated one month after surgery. Results: Patients were 8 (40% males and 12 (60% females with a mean age of 49.9 ± 3.8 (25 to 70 years. Left and right MCA were involved in 7 (35% and 13 (65% patients, respectively. Four (20% patients died within one month after surgery (3 females and one male, mean age of 59.0 ± 4.5 vs. 47.6 ± 3.4 in survived patients, p < 0.001. The mean of baseline Glasscow Coma Scale (GCS score estimated 8.60 ± 1.55 in survived patients and 6.75 ± 0.95 in patients who died (p < 0.05. Conclusions: The survival rate of malignant MCA infarction treated with decompressive hemicraniectomy was the same as previous reports. MCA infarction mortality increased with age and lower admission GCS score.

  15. The effect of rapid decompression on femur blood flow of rabbits

    International Nuclear Information System (INIS)

    Yu Shaoning; Tian Wuxun; Zhu Xiangqi


    PURPOSE: To study the influence of regional blood flow in femur trochanter (FT) of rabbits' under rapid decompression after exposure to hyperbaric air. METHODS: Rabbits were placed in a hyperbaric chamber and exposed to the pressure of 0.5 MPa for 1.5 h, and the pressure was reduced to the atmosphere pressure at a uniform rate of 0.03 mPa/min. The regional blood flow of FT in rabbits were measured with 133 Xe washout methods. RESULTS: The normal average regional blood flow in left and right FT were 14.5 +- 1.7 and 14.1 +- 1.9 ml/(min·100g) respectively. After exposure to hyperbaric air with rapid decompression, the average regional blood flow of left and right FT were 11.1 +- 1.2 and 10.5 +- 1.6 ml/(min·100g) respectively. But the symptoms of dysbarism in these rabbits were various each other. CONCLUSIONS: After being exposed to hyperbaric air with rapid decompression, the blood flow of rabbits' femur trochanter were noticeably reduced

  16. Expansion of Chiari I-associated syringomyelia after posterior-fossa decompression. (United States)

    Gil, Z; Rao, S; Constantini, S


    Chiari I malformation (CMI) is an abnormality that involves caudal herniation of the cerebellar tonsils into the foramen magnum. CMI has been shown to be closely associated with the development of syringomyelia (SM). Several theories have emerged to explain the apparent correlation between the existence of CMI with subsequent development of SM. However, the exact mechanism of the evolution of SM is still subject to controversy. We report here the case of a 12-year-old girl admitted to hospital with headache, vomiting, ataxia, and moderate pyramidal signs. Radiological evaluation revealed the presence of CMI, accompanied by a small SM. The patient underwent posterior fossa decompression and improved significantly. She was re-admitted 6 months later with clinical evidence of progressive spinal cord dysfunction. MR revealed gross expansion of the syrinx. This case raises questions regarding the pathophysiology of CMI and its association with SM. The case indicates the need for neurological and radiological follow-up for patients undergoing posterior fossa decompression due to CMI, even for those without an initial syrinx. This is the first report known to us of expansion of a syrinx following decompression of an associated CMI.

  17. Technical and economic analysis of natural ga decompression: recovery of both electricity and process frigories

    International Nuclear Information System (INIS)

    Fracastoro, G.V.; Perino, M.


    The most significant results of the economic analysis on natural gas decompression, specifically referring to EniChem's newly built plant in Porto Marghera, are shown in this article. The analysis was carried out in the framework of rational utilization of energy in compliance with Law No.9 of January 9, 1991. In order to optimize the final use of energy, the service rendered being equal (natural gas was decompressed owing to safety and technical reasons), a possible solution was found, i.e. to replace thermodynamic lamination by an expansion process in a two-stage turbine expansor (recovery of physical energy in pressure). Thanks to this new solution, the above mentioned recovery operation can be integrated by recovering the frigories associated with the availability of the fluid stream (physical energy in temperature) at the outlet of the generator, in order to supply the refrigerating quantity needed to carry out some phases of the steam-cracking process, which takes place in an area lying close to the new decompression plant

  18. DSP accelerator for the wavelet compression/decompression of high- resolution images

    Energy Technology Data Exchange (ETDEWEB)

    Hunt, M.A.; Gleason, S.S.; Jatko, W.B.


    A Texas Instruments (TI) TMS320C30-based S-Bus digital signal processing (DSP) module was used to accelerate a wavelet-based compression and decompression algorithm applied to high-resolution fingerprint images. The law enforcement community, together with the National Institute of Standards and Technology (NISI), is adopting a standard based on the wavelet transform for the compression, transmission, and decompression of scanned fingerprint images. A two-dimensional wavelet transform of the input image is computed. Then spatial/frequency regions are automatically analyzed for information content and quantized for subsequent Huffman encoding. Compression ratios range from 10:1 to 30:1 while maintaining the level of image quality necessary for identification. Several prototype systems were developed using SUN SPARCstation 2 with a 1280 {times} 1024 8-bit display, 64-Mbyte random access memory (RAM), Tiber distributed data interface (FDDI), and Spirit-30 S-Bus DSP-accelerators from Sonitech. The final implementation of the DSP-accelerated algorithm performed the compression or decompression operation in 3.5 s per print. Further increases in system throughput were obtained by adding several DSP accelerators operating in parallel.

  19. MR imaging of the central nervous system in diving-related decompression illness

    International Nuclear Information System (INIS)

    Reuter, M.; Hutzelmann, A.; Steffens, J.C.; Heller, M.; Fritsch, G.


    Purpose: This investigation was conducted to determine whether MR imaging showed cerebral or spinal damage in acute diving-related decompression illness, a term that includes decompressions sickness (DCS) and arterial gas embolism (AGE). Material and Methods: A total of 16 divers with dysbaric injuries were examined after the initiation of therapeutic recompression. Their injuries comprised: neurological DCS II n=8; AGE n=7; combined cerebral-AGE/spinal-DCS n=1. T1- and T2-weighted images of the brain were obtained in 2 planes. In addition, the spinal cord was imaged in 7 subjects. The imaging findings were correlated with the neurological symptoms. Results: MR images of the head showed ischemic cerebrovascular lesions in 6/8 patients with AGE but showed focal hyperintensities in only 2/8 divers with DCS. Spinal-cord involvement was detected in 1/7 examinations, which was the combined cerebral-AGE/spinal-DCS case. There was agreement between the locations of the documented lesions and the clinical manifestations. Conclusion: MR readily detects cerebral damage in AGE but yields low sensitivity in DCS. A negative MR investigation cannot rule out AGE or DCS. However, MR is useful in the examination of patients with decompression illness. (orig.)

  20. Endoscopic resection of acetabular screw tip to decompress sciatic nerve following total hip arthroplasty. (United States)

    Yoon, Sun-Jung; Park, Myung-Sik; Matsuda, Dean K; Choi, Yun Ho


    Sciatic nerve injuries following total hip arthroplasty are disabling complications. Although degrees of injury are variable from neuropraxia to neurotmesis, mechanical irritation of sciatic nerve might be occurred by protruding hardware. This case shows endoscopic decompression for protruded acetabular screw irritating sciatic nerve, the techniques described herein may permit broader arthroscopic/endoscopic applications for management of complications after reconstructive hip surgery. An 80-year-old man complained of severe pain and paresthesias following acetabular component revision surgery. Physical findings included right buttock pain with radiating pain to lower extremity. Radiographs and computed tomography imaging showed that the sharp end of protruded screw invaded greater sciatic foramen anterior to posterior and distal to proximal direction at sciatic notch level. A protruding tip of the acetabular screw at the sciatic notch was decompressed by use of techniques gained from experience performing endoscopic sciatic nerve decompression. The pre-operative pain and paresthesias resolved post-operatively after recovering from anesthesia. This case report describes the first documented endoscopic resection of the tip of the acetabular screw irritating sciatic nerve after total hip arthroplasty. If endoscopic resection of an offending acetabular screw can be performed in a safe and minimally invasive manner, one can envision a future expansion of the role of hip arthroscopic surgery in several complications management after total hip arthroplasty.

  1. Surgical decompression in endocrine orbitopathy. Visual evoked potential evaluation and effect on the optic nerve. (United States)

    Clauser, Luigi C; Tieghi, Riccardo; Galie', Manlio; Franco, Filippo; Carinci, Francesco


    Endocrine orbitopathy (EO) represents the most frequent and important extrathyroidal stigma of Graves disease. This chronic autoimmune condition involves the orbital contents, including extraocular muscles, periorbital connective-fatty tissue and lacrimal gland. The increase of fat tissue and the enlargement of extraocular muscles within the bony confines of the orbit leads to proptosis, and in the most severe cases optic neuropathy, caused by compression and stretching of the optic nerve. The congestion and the pressure of the enlarged muscles, constrict the nerve and can lead to reduced sight or loss of vision with the so called "orbital apex syndrome". Generally surgical treatment of EO, based on fat and/or orbital wall expansion, is possible and effective in improving exophthalmos and diplopia. Since there are limited reports focussing on optic neuropathy recovery after fat and/or orbital walls decompression the Authors decided to perform a retrospective analysis on a series of patients affected by EO. The study population was composed of 10 patients affected by EO and presenting to the Unit of Cranio Maxillofacial Surgery, Center for Craniofacial Deformities & Orbital Surgery St. Anna Hospital and University, Ferrara, Italy, for evaluation and treatment. A complete Visual Evoked Potentials (VEP) evaluation was performed. There were seven women and three men with a median age of 55 years. Optic nerve VEP amplitude and latency were recorded as normal or pathological. Abnormal results were scored as moderate, mild and severe. Differences in VEP pre and post-operatively were recorded as present or absent (i.e. VEP Delta). Pearson chi square test was applied. There were 20 operated orbits. The first VEP evaluation was performed 3.2 months before surgery and post-operative VEP control was done after a mean of 18.7 months. Fat decompression was performed in all cases and eight patients had also bony decompression. VEP amplitude and latency were affected in 10 and 15

  2. Osteonecrosis of femoral head: Treatment by core decompression and vascular pedicle grafting

    Directory of Open Access Journals (Sweden)

    Babhulkar Sudhir


    Full Text Available Background: Femoral head-preserving core decompression and bone grafting have shown excellent result in preventing collapse. The use of vascularized grafts have shown better clinical results. The vascular pedicle bone graft is an easy to perform operation and does not require special equipment. We analyzed and report a series of patients of osteonecrosis of femoral head treated by core decompression and vascular pedicle grafting of part of iliac crest based on deep circumflex iliac vessels. Materials and Methods: The article comprises of the retrospective study of 31 patients of osteonecrosis of femoral head in stage II and III treated with core decompression and vascular pedicle grafting by using part of iliac crest with deep circumflex iliac vessels from January 1990 to December 2005. The young patients with a mean age 32 years (18-52 years with a minimum follow-up of five years were included for analysis. Sixteen patients had osteonecrosis following alcohol abuse, 12 patients following corticosteroid consumption, 3 patients had idiopathic osteonecrosis. Nine patients were stage IIB, and 22 patients were stage IIIC according to ARCO′s system. The core decompression and vascular pedicle grafting was performed by anterior approach by using part of iliac crest with deep circumflex iliac vessels. Results: Digital subtraction arteriography performed in 9 patients at the end of 12 weeks showed the patency of deep circumflex artery in all cases, and bone scan performed in 6 other patients showed high uptake in the grafted area of the femoral head proving the efficacy of the operative procedure. Out of 31 patients, only one patient progressed to collapse and total joint replacement was advised. At the final follow up period of 5-8 years, Harris Hip Score improved mean ± SD of 28.2 ± 6.4 ( p < 0.05. Forty-eight percent of patients had an improvement in Harris Hip Score of more that 28 points. Conclusion: The core decompression and vascular pedicle

  3. Microvascular Decompression for Classical Trigeminal Neuralgia Caused by Venous Compression: Novel Anatomic Classifications and Surgical Strategy. (United States)

    Wu, Min; Fu, Xianming; Ji, Ying; Ding, Wanhai; Deng, Dali; Wang, Yehan; Jiang, Xiaofeng; Niu, Chaoshi


    Microvascular decompression of the trigeminal nerve is the most effective treatment for trigeminal neuralgia. However, when encountering classical trigeminal neuralgia caused by venous compression, the procedure becomes much more difficult, and failure or recurrence because of incomplete decompression may become frequent. This study aimed to investigate the anatomic variation of the culprit veins and discuss the surgical strategy for different types. We performed a retrospective analysis of 64 consecutive cases in whom veins were considered as responsible vessels alone or combined with other adjacent arteries. The study classified culprit veins according to operative anatomy and designed personalized approaches and decompression management according to different forms of compressive veins. Curative effects were assessed by the Barrow Neurological Institute (BNI) pain intensity score and BNI facial numbness score. The most commonly encountered veins were the superior petrosal venous complex (SPVC), which was artificially divided into 4 types according to both venous tributary distribution and empty point site. We synthetically considered these factors and selected an approach to expose the trigeminal root entry zone, including the suprafloccular transhorizontal fissure approach and infratentorial supracerebellar approach. The methods of decompression consist of interposing and transposing by using Teflon, and sometimes with the aid of medical adhesive. Nerve combing (NC) of the trigeminal root was conducted in situations of extremely difficult neurovascular compression, instead of sacrificing veins. Pain completely disappeared in 51 patients, and the excellent outcome rate was 79.7%. There were 13 patients with pain relief treated with reoperation. Postoperative complications included 10 cases of facial numbness, 1 case of intracranial infection, and 1 case of high-frequency hearing loss. The accuracy recognition of anatomic variation of the SPVC is crucial for the

  4. Analysis of clinical outcomes of linear vs. deep stop decompression from 3.5 to 6 atmospheres absolute (350 - 600 kpa) in awake rats

    DEFF Research Database (Denmark)

    Cronjé, Frans J; Meintjes, W A Jack; Bennett, Peter B


    Recreational divers are introducing "deep stops" at half the depth (HD-DS) to reduce the risk of spinal DCS with only Doppler evidence to support it. Therefore this research was designed to show the effect of an HD-DS on spinal DCS manifestations by evaluating whether: (1) air diving-induced spinal...... DCS could be produced in awake, freely moving rats at 3.5-6.0 atm abs (350-600 kPa); and (2) whether the introduction of an HD-DS reduced spinal DCS in such a model. Fifty-one female, Wistar rats (221 to 450 g) underwent one-hour compression at 350 to 600 kPa with seven minutes of decompression with....../without a five-minute DS (HD-DS / No-DS). Animals were observed for three hours. Outcomes were classified as: (1) asymptomatic; (2) breathing difficulties; (3) paralysis/weakness; (4) immobility; or (5) death. Eight animals, exposed to 385 kPa air breathing for 60 minutes followed by a three-staged decompression...

  5. Percutaneous laser disc decompression versus conventional microdiscectomy for patients with sciatica: Two-year results of a randomised controlled trial. (United States)

    Brouwer, Patrick A; Brand, Ronald; van den Akker-van Marle, M Elske; Jacobs, Wilco Ch; Schenk, Barry; van den Berg-Huijsmans, Annette A; Koes, Bart W; Arts, Mark A; van Buchem, M A; Peul, Wilco C


    Background Percutaneous laser disc decompression is a minimally invasive treatment, for lumbar disc herniation and might serve as an alternative to surgical management of sciatica. In a randomised trial with two-year follow-up we assessed the clinical effectiveness of percutaneous laser disc decompression compared to conventional surgery. Materials and methods This multicentre randomised prospective trial with a non-inferiority design, was carried out according to an intent-to-treat protocol with full institutional review board approval. One hundred and fifteen eligible surgical candidates, with sciatica from a disc herniation smaller than one-third of the spinal canal, were randomly allocated to percutaneous laser disc decompression ( n = 55) or conventional surgery ( n = 57). The main outcome measures for this trial were the Roland-Morris Disability Questionnaire for sciatica, visual analogue scores for back and leg pain and the patient's report of perceived recovery. Results The primary outcome measures showed no significant difference or clinically relevant difference between the two groups at two-year follow-up. The re-operation rate was 21% in the surgery group, which is relatively high, and with an even higher 52% in the percutaneous laser disc decompression group. Conclusion At two-year follow-up, a strategy of percutaneous laser disc decompression, followed by surgery if needed, resulted in non-inferior outcomes compared to a strategy of microdiscectomy. Although the rate of reoperation in the percutaneous laser disc decompression group was higher than expected, surgery could be avoided in 48% of those patients that were originally candidates for surgery. Percutaneous laser disc decompression, as a non-surgical method, could have a place in the treatment arsenal of sciatica caused by contained herniated discs.

  6. The effects of venting and decompression on Yellow Tang (Zebrasoma flavescens in the marine ornamental aquarium fish trade

    Directory of Open Access Journals (Sweden)

    Emily S. Munday


    Full Text Available Each year, over 45 countries export 30 million fish from coral reefs as part of the global marine ornamental aquarium trade. This catch volume is partly influenced by collection methods that cause mortality. Barotrauma in fish resulting from forced ascent from depth can contribute to post-collection mortality. However, implementing decompression stops during ascent can prevent barotrauma. Conversely, venting (puncturing the swim bladder to release expanded internal gas following ascent can mitigate some signs of barotrauma like positive buoyancy. Here, we evaluate how decompression and venting affect stress and mortality in the Yellow Tang (Zebrasoma flavescens. We examined the effects of three ascent treatments, each with decompression stops of varying frequency and duration, coupled with or without venting, on sublethal effects and mortality using histology and serum cortisol measurements. In fish subjected to ascent without decompression stops or venting, a mean post-collection mortality of 6.2% occurred within 24 h of capture. Common collection methods in the fishery, ascent without decompression stops coupled with venting, or one long decompression stop coupled with venting, resulted in no mortality. Histopathologic examination of heart, liver, head kidney, and swim bladder tissues in fish 0d and 21d post-collection revealed no significant barotrauma- or venting-related lesions in any treatment group. Ascent without decompression stops resulted in significantly higher serum cortisol than ascent with many stops, while venting alone did not affect cortisol. Future work should examine links in the supply chain following collection to determine if further handling and transport stressors affect survivorship and sublethal effects.

  7. Enough positive rate of paraspinal mapping and diffusion tensor imaging with levels which should be decompressed in lumbar spinal stenosis. (United States)

    Chen, Hua-Biao; Zhong, Zhi-Wei; Li, Chun-Sheng; Bai, Bo


    In lumbar spinal stenosis, correlating symptoms and physical examination findings with decompression levels based on common imaging is not reliable. Paraspinal mapping (PM) and diffusion tensor imaging (DTI) may be possible to prevent the false positive occurrences with MRI and show clear benefits to reduce the decompression levels of lumbar spinal stenosis than conventional magnetic resonance imaging (MRI) + neurogenic examination (NE). However, they must have enough positive rate with levels which should be decompressed at first. The study aimed to confirm that the positive of DTI and PM is enough in levels which should be decompressed in lumbar spinal stenosis. The study analyzed the positive of DTI and PM as well as compared the preoperation scores to the postoperation scores, which were assessed preoperatively and at 2 weeks, 3 months 6 months, and 12 months postoperatively. 96 patients underwent the single level decompression surgery. The positive rate among PM, DTI, and (PM or DTI) was 76%, 98%, 100%, respectively. All post-operative Oswestry Disability Index (ODI), visual analog scale for back pain (VAS-BP) and visual analog scale for leg pain (VAS-LP) scores at 2 weeks postoperatively were measured improvement than the preoperative ODI, VAS-BP and VAS-LP scores with statistically significance (p-value = 0.000, p-value = 0.000, p-value = 0.000, respectively). In degenetive lumbar spinal stenosis, the positive rate of (DTI or PM) is enough in levels which should be decompressed, thence using the PM and DTI to determine decompression levels will not miss the level which should be operated. Copyright © 2016 The Japanese Orthopaedic Association. Published by Elsevier B.V. All rights reserved.

  8. Magma heating by decompression-driven crystallization beneath andesite volcanoes. (United States)

    Blundy, Jon; Cashman, Kathy; Humphreys, Madeleine


    Explosive volcanic eruptions are driven by exsolution of H2O-rich vapour from silicic magma. Eruption dynamics involve a complex interplay between nucleation and growth of vapour bubbles and crystallization, generating highly nonlinear variation in the physical properties of magma as it ascends beneath a volcano. This makes explosive volcanism difficult to model and, ultimately, to predict. A key unknown is the temperature variation in magma rising through the sub-volcanic system, as it loses gas and crystallizes en route. Thermodynamic modelling of magma that degasses, but does not crystallize, indicates that both cooling and heating are possible. Hitherto it has not been possible to evaluate such alternatives because of the difficulty of tracking temperature variations in moving magma several kilometres below the surface. Here we extend recent work on glassy melt inclusions trapped in plagioclase crystals to develop a method for tracking pressure-temperature-crystallinity paths in magma beneath two active andesite volcanoes. We use dissolved H2O in melt inclusions to constrain the pressure of H2O at the time an inclusion became sealed, incompatible trace element concentrations to calculate the corresponding magma crystallinity and plagioclase-melt geothermometry to determine the temperature. These data are allied to ilmenite-magnetite geothermometry to show that the temperature of ascending magma increases by up to 100 degrees C, owing to the release of latent heat of crystallization. This heating can account for several common textural features of andesitic magmas, which might otherwise be erroneously attributed to pre-eruptive magma mixing.

  9. Facial nerve decompression surgery using bFGF-impregnated biodegradable gelatin hydrogel in patients with Bell palsy. (United States)

    Hato, Naohito; Nota, Jumpei; Komobuchi, Hayato; Teraoka, Masato; Yamada, Hiroyuki; Gyo, Kiyofumi; Yanagihara, Naoaki; Tabata, Yasuhiko


    Basic fibroblast growth factor (bFGF) promotes the regeneration of denervated nerves. The aim of this study was to evaluate the regeneration-facilitating effects of novel facial nerve decompression surgery using bFGF in a gelatin hydrogel in patients with severe Bell palsy. Prospective clinical study. Tertiary referral center. Twenty patients with Bell palsy after more than 2 weeks following the onset of severe paralysis were treated with the new procedure. The facial nerve was decompressed between tympanic and mastoid segments via the mastoid. A bFGF-impregnated biodegradable gelatin hydrogel was placed around the exposed nerve. Regeneration of the facial nerve was evaluated by the House-Brackmann (H-B) grading system. The outcomes were compared with the authors' previous study, which reported outcomes of the patients who underwent conventional decompression surgery (n = 58) or conservative treatment (n = 43). The complete recovery (H-B grade 1) rate of the novel surgery (75.0%) was significantly better than the rate of conventional surgery (44.8%) and conservative treatment (23.3%). Every patient in the novel decompression surgery group improved to H-B grade 2 or better even when undergone between 31 and 99 days after onset. Advantages of this decompression surgery are low risk of complications and long effective period after onset of the paralysis. To the authors' knowledge, this is the first clinical report of the efficacy of bFGF using a new drug delivery system in patients with severe Bell palsy.

  10. Simulation of gas bubbles in hypobaric decompressions: roles of O2, CO2, and H2O. (United States)

    Van Liew, H D; Burkard, M E


    To gain insight into the special features of bubbles that may form in aviators and astronauts, we simulated the growth and decay of bubbles in two hypobaric decompressions and a hyperbaric one, all with the same tissue ratio (TR), where TR is defined as tissue PN2 before decompression divided by barometric pressure after. We used an equation system which is solved by numerical methods and accounts for simultaneous diffusion of any number of gases as well as other major determinants of bubble growth and absorption. We also considered two extremes of the number of bubbles which form per unit of tissue. A) Because physiological mechanisms keep the partial pressures of the "metabolic" gases (O2, CO2, and H2O) nearly constant over a range of hypobaric pressures, their fractions in bubbles are inversely proportional to pressure and their large volumes at low pressure add to bubble size. B) In addition, the large fractions facilitate the entry of N2 into bubbles, and when bubble density is low, enhance an autocatalytic feedback on bubble growth due to increasing surface area. C) The TR is not closely related to bubble size; that is when two different decompressions have the same TR, metabolic gases cause bubbles to grow larger at lower hypobaric pressures. We conclude that the constancy of partial pressures of metabolic gases, unimportant in hyperbaric decompressions, affects bubble size in hypobaric decompressions in inverse relation to the exposure pressure.

  11. Transcranial doppler sonography in two patients who underwent decompressive craniectomy for traumatic brain swelling: report of two cases

    Directory of Open Access Journals (Sweden)

    Bor-Seng-Shu Edson


    Full Text Available The role of decompressive craniectomy in the treatment of severe posttraumatic cerebral swelling remains quite a controversial issue. To the best of our knowledge, there is no study demonstrating the effect of decompressive craniectomy on cerebral blood flow (CBF velocity by means of transcranial Doppler sonography (TCD. We present two patients who developed traumatic brain swelling and uncontrollable intracranial hypertension with coma and signs of transtentorial herniation. One patient underwent bifrontal, while the second, unilateral, frontotemporoparietal decompressive craniectomy with dural expansion. In both patients, TCD examinations were performed immediately before and after surgery to study the cerebral hemodynamic changes related to the operations. Pre and postoperative TCD examinations demonstrated a significant increase in blood flow velocity in the intracranial arteries in both subjects. In conclusion, our cases suggest that decompressive craniectomy with dural expansion may result in elevation of CBF velocity in patients with massive brain swelling. The increase in CBF velocity appears to occur not only in the decompressed hemisphere, but also on the opposite side.

  12. The effect of partial portal decompression on portal blood flow and effective hepatic blood flow in man: a prospective study. (United States)

    Rosemurgy, A S; McAllister, E W; Godellas, C V; Goode, S E; Albrink, M H; Fabri, P J


    With the advent of transjugular intrahepatic porta-systemic stent shunt and the wider application of the surgically placed small diameter prosthetic H-graft portacaval shunt (HGPCS), partial portal decompression in the treatment of portal hypertension has received increased attention. The clinical results supporting the use of partial portal decompression are its low incidence of variceal rehemorrhage due to decreased portal pressures and its low rate of hepatic failure, possibly due to maintenance of blood flow to the liver. Surprisingly, nothing is known about changes in portal hemodynamics and effective hepatic blood flow following partial portal decompression. To prospectively evaluate changes in portal hemodynamics and effective hepatic blood flow brought about by partial portal decompression, the following were determined in seven patients undergoing HGPCS: intraoperative pre- and postshunt portal vein pressures and portal vein-inferior vena cava pressure gradients, intraoperative pre- and postshunt portal vein flow, and pre- and postoperative effective hepatic blood flow. With HGPCS, portal vein pressures and portal vein-inferior vena cava pressure gradients decreased significantly, although portal pressures remained above normal. In contrast to the significant decreases in portal pressures, portal vein blood flow and effective hepatic blood flow do not decrease significantly. Changes in portal vein pressures and portal vein-inferior vena cava pressure gradients are great when compared to changes in portal vein flow and effective hepatic blood flow. Reduction of portal hypertension with concomitant maintenance of hepatic blood flow may explain why hepatic dysfunction is avoided following partial portal decompression.

  13. [Research on the incidence of decompression sickness in compressed air works. The development of its recent five years' study]. (United States)

    Mano, Y; Shibayama, M; Matsui, Y


    Compressed air works have been used as the safest construction work for the basic underground or underwater compressed shield or caisson works in Japan; however, the workers who were exposed to the compressed fields must have put themselves at risk of decompression sickness. Decompression sickness is generally considered to be due to the bubble effects and the bubbles originate from the supersaturated gas dissolved in the blood and other tissues. The standard decompression schedule by the Ministry of Labor has been practically applied at the end of compressed air works, and the laborers decompress slowly from the bottom pressure to the surface according to the schedule. It is difficult to completely prevent the sickness and the average percentage of contracting "bends," using the Japanese standard decompression schedule, is considered to be 0.54%. But previous papers reported higher incidences from 1.42 to 3.3% or more. We have continued an actual investigation on the incidence, and the number of the exposed trials amounted to nearly a hundred thousand. These data were compared between recent five years' group and before. Eventually, it was ascertained that the incidence has been significantly decreased in the recent five years; however, greater care in occupational safety control is still needed.

  14. Preoperative evaluation of neurovascular relationships for microvascular decompression in the cerebellopontine angle in a virtual reality environment. (United States)

    Du, Zhuo-Ying; Gao, Xiang; Zhang, Xiao-Luo; Wang, Zhi-Qiu; Tang, Wei-Jun


    In this paper the authors' goal was to evaluate the feasibility and efficacy of a virtual reality (VR) system in preoperative planning for microvascular decompression (MVD) procedures treating idiopathic trigeminal neuralgia and hemifacial spasm. The system's role in surgical simulation and training was also assessed. Between May 2008 and April 2009, the authors used the Dextroscope system to visualize the neurovascular complex and simulate MVD in the cerebellopontine angle in a VR environment in 16 patients (6 patients had trigeminal neuralgia and 10 had hemifacial spasm). Reconstructions were carried out 2-3 days before MVD. Images were printed in a red-blue stereoscopic format for teaching and discussion and were brought into the operating room to be compared with real-time intraoperative findings. The VR environment was a powerful aid for spatial understanding of the neurovascular relationship in MVD for operating surgeons and trainees. Through an initial series of comparison/confirmation experiences, the senior neurosurgeon became accustomed to the system. He could predict intraoperative problems and simulate surgical maneuvering, which increased his confidence in performing the procedure. The Dextroscope system is an easy and rapid method to create a stereoscopic neurovascular model for MVD that is highly concordant with intraoperative findings. It effectively shortens the learning curve and adds to the surgeon's confidence.

  15. The results of decompressive surgery and instrumented posterolateral fusion in refractory degenerative spondylolisthesis

    Directory of Open Access Journals (Sweden)

    Behtash H


    Full Text Available "nBackground: Degenerative spondylolisthesis is a common disease of the lumbar spine especially in older ones. The disease represents a challenge to the treating physician. At present, for those patients that deteriorate clinically, there are many proposed algorithms for the surgical treatment. This before and after study was undertaken to assess the surgical results of decompression and instrumented posterolateral fusion in these patients. "nMethods: The study population consisted of 23 patients who had undergone no prior surgery for degenerative spondylolisthesis on the lumbar spine. These patients were treated by decompression, bilateral posterolateral fusion, and segmental (pedicle screw instrumentation with mean follow-up of 29 months (range, 13-73 months. Finally, The clinical results were evaluated for all patients by means of an Oswestry Disability Index (ODI version 2.1, the Henderson's functional capacity, and persistence of leg symptoms, low back pain or claudication. Mann-Whitney and Chi-Square tests were used to assess the average values and comparison, respectively. "nResults: Henderson's functional capacity at the last visit session was excellent in 14 (60.9%, good in 7 (30.4%, fair in 2 (8.7% cases. ODI decreased from 72.2% (50-88% preoperatively to 14.4% (0-54% at the latest follow-up visit. A history of leg pain or claudication was correlated significantly with the amount of decline in ODI score and Henderson's functional capacity (p<0.05. "nConclusion: In spite of limited number of our patients, decompressive surgery plus instrumented posterolateral fusion is a safe, reliable, and satisfactory procedure for treating degenerative lumbar spondylolisthesis. This procedure may be done when conservative treatment was failed and psychological problems can be ruled out.

  16. Unilateral Approach for Bilateral Decompression of Lumbar Spinal Stenosis: A Minimal Invasive Surgery

    International Nuclear Information System (INIS)

    Usman, M.; Ali, M.; Khanzada, K.; Haq, N.U.; Aman, R.; Ali, M.


    Objective: To assess the feasibility and efficacy of a novel, minimally invasive spinal surgery technique for the correction of lumbar spinal stenosis involving unilateral approach for bilateral decompression. Study Design: Cross-sectional observational study. Place and Duration of Study: Neurosurgery Department of PGMI, Lady Reading Hospital, Peshawar, from January to December 2010. Methodology: A total of 60 patients with lumbar stenosis were randomly assigned to undergo either a conventional laminectomy (30 patients, Group A), or a unilateral approach (30 patients, Group B). Clinical outcomes was measured using the scale of Finneson and Cooper. All the data was collected by using a proforma and different parameters were assessed for a minimum follow-up period of three months. Data was analyzed by descriptive statistics using SPSS software version 17. Results: Adequate decompression was achieved in all patients. Compared with patients in the conventional laminectomy group, patients who received the novel procedure (unilateral approach) had a reduced mean duration of hospital stay, a faster recovery rate and majority of the patients (88.33%) had an excellent to fair operative result according to the Finneson and Cooper scale. Five major complications occurred in all patient groups, 2 patients had unintended dural rent and 2 wound dehiscence each and fifth patient had worsening of symptoms. There was no mortality in the series. Conclusion: The ultimate goal of the unilateral approach to treat lumbar spinal stenosis is to achieve adequate decompression of the neural elements. An additional benefit of a minimally invasive approach is adequate preservation of vertebral stability, as it requires only minimal muscle trauma, preservation of supraspinous/intraspinous ligament complex and spinous process, therefore, allows early mobilization. This also shortens the hospital stay, reduces postoperative back pain, and leads to satisfactory outcome. (author)

  17. Anterior versus lateral needle decompression of tension pneumothorax: comparison by computed tomography chest wall measurement. (United States)

    Sanchez, Leon D; Straszewski, Shannon; Saghir, Amina; Khan, Atif; Horn, Erin; Fischer, Christopher; Khosa, Faisal; Camacho, Marc A


    Recent research describes failed needle decompression in the anterior position. It has been hypothesized that a lateral approach may be more successful. The aim of this study was to identify the optimal site for needle decompression. A retrospective study was conducted of emergency department (ED) patients who underwent computed tomography (CT) of the chest as part of their evaluation for blunt trauma. A convenience sample of 159 patients was formed by reviewing consecutive scans of eligible patients. Six measurements from the skin surface to the pleural surface were made for each patient: anterior second intercostal space, lateral fourth intercostal space, and lateral fifth intercostal space on the left and right sides. The distance from skin to pleura at the anterior second intercostal space averaged 46.3 mm on the right and 45.2 mm on the left. The distance at the midaxillary line in the fourth intercostal space was 63.7 mm on the right and 62.1 mm on the left. In the fifth intercostal space the distance was 53.8 mm on the right and 52.9 mm on the left. The distance of the anterior approach was statistically less when compared to both intercostal spaces (p < 0.01). With commonly available angiocatheters, the lateral approach is less likely to be successful than the anterior approach. The anterior approach may fail in many patients as well. Longer angiocatheters may increase the chances of decompression, but would also carry a higher risk of damage to surrounding vital structures. © 2011 by the Society for Academic Emergency Medicine.

  18. The urgency of surgical decompression in acute central cord injuries with spondylosis and without instability. (United States)

    Lenehan, Brian; Fisher, Charles G; Vaccaro, Alex; Fehlings, Michael; Aarabi, Bizhan; Dvorak, Marcel F


    Systematic review, ambispective analysis of observational data. To make recommendations as to whether or not urgent surgical decompression is ever indicated as the optimal treatment for enhancing neurologic recovery in a patient with acute central cord injury without fracture or instability. There are currently no standards regarding the role and timing of decompression in acute traumatic central cord syndrome. In the setting of TCCS without spinal column instability, much controversy exists. We have performed a thorough literature search based on the following question: "Is there a role for urgent (within 24 hours from injury to surgery) surgical decompression in acute central cord syndrome without fracture or instability specifically to enhance neurologic recovery?" Data including patient demographics, mechanism of injury, comorbidities, neurologic status, and surgical treatment was analyzed from a multicenter STSG observational database. Outcome measured included ASIA Motor Score, ASIA Grade, Functional Independence Measure (FIM) Score, SF-36, Sphincter Disturbance, and Ambulatory status. Measures were recorded on admission, discharge, 6 months and 1 year. At 12-month follow-up, early surgery resulted in a 6.31 point greater improvement in total motor score than did the late surgery group, with a P = 0.0358. At 6-month follow-up, early surgery result in higher chance of improvement in ASIA Grade than late surgery, with an odds ratio = 3.39, while at 12-month follow-up early surgery resulted in a higher chance of improvement in ASIA Grade, with an odds ratio of 2.81. Patients who were operated on within 24 hours had 7.79 U more improvement in FIM Total Score than late surgery at 6 month follow-up, with P = 0.0474. The consensus of experts following review of relevant and examination of observational dataset concluded that it is reasonable and safe to consider early surgical decompression in patients with profound neurologic deficit (ASIA = C) and persistent

  19. Inadequate peak expiratory flow meter characteristics detected by a computerised explosive decompression device

    DEFF Research Database (Denmark)

    Miller, M.R.; Atkins, P.R.; Pedersen, O.F.


    Methods: The dynamic response of mini-Wright (MW), Vitalograph (V), TruZone (TZ), MultiSpiro (MS) and pneumotachograph (PT) flow meters was tested by delivering two differently shaped flow-time profiles from a computer controlled explosive decompression device fitted with a fast response solenoid.......1) and 257 (39.2), respectively, and at ≈200 l/min they were 51 (23.9) and 1 (0.5). All the meters met ATS accuracy requirements when tested with their waveforms. Conclusions: An improved method for testing the dynamic response of flow meters detects marked overshoot (underdamping) of TZ and MS responses...

  20. Utilization of steam- and explosion-decompressed aspen wood by some anaerobes

    Energy Technology Data Exchange (ETDEWEB)

    Khan, A W; Asther, M; Giuliano, C


    Tests made to study the suitability of using steam- and explosion-decompressed aspen wood as a substrate in anaerobic fermentations indicated that after washing with dilute NaOH it becomes less than 80% accessible to both mesophilic and thermophilic cellulolytic anaerobes and cellulases, compared with delignified, ball-milled pulp. After washing, this material was also suitable for the single-step conversion of cellulose to EtOH using cocultures consisting of cellulolytic and EtOH-producing saccharolytic anaerobes; and without and after washing by the use of cellulolytic enzymes and ethanologenic anaerobes.

  1. Lumbar Radiculopathy in the Setting of Degenerative Scoliosis: MIS Decompression and Limited Correction are Better Options. (United States)

    Fontes, Ricardo B; Fessler, Richard G


    Surgery for adult spinal deformity (ASD) has emerged as an efficient treatment alternative, but it is fraught with potential perioperative morbidity, incompletely mitigated by emerging minimally invasive surgical techniques. In mild-to-moderate ASD balanced in the sagittal plane, there are situations in which the counterintuitive simple decompression through a foraminotomy or laminectomy, or even a short-segment fusion may be an attractive treatment. This article presents a case example and the authors' treatment rationale and reviews the limited available literature supporting it. Copyright © 2017 Elsevier Inc. All rights reserved.

  2. Cost-effectiveness of decompression according to Gill versus instrumented spondylodesis in the treatment of sciatica due to low grade spondylolytic spondylolisthesis: A prospective randomised controlled trial [NTR1300

    NARCIS (Netherlands)

    M.P. Arts (Mark); M.J.T. Verstegen (Marco); R. Brand (René); B.W. Koes (Bart); M.E. van den Akker-van Marle (Elske); W.C. Peul (Wilco)


    textabstractBackground. Nerve root decompression with instrumented spondylodesis is the most frequently performed surgical procedure in the treatment of patients with symptomatic low-grade spondylolytic spondylolisthesis. Nerve root decompression without instrumented fusion, i.e. Gill's procedure,

  3. Risk of Decompression Sickness in Shallow No-Stop Air Diving An Analysis of Naval Safety Center Data 1990-1994

    National Research Council Canada - National Science Library

    Flynn, E


    ...) in shallow no-stop air diving using current U.S. Navy no-decompression limits (USN57). Navy and Marine Corp divers performed 163,400 no-decompression dives between 21 and 55 feet of sea water (fsw...

  4. Successful Left-Heart Decompression during Extracorporeal Membrane Oxygenation in an Adult Patient by Percutaneous Transaortic Catheter Venting

    Directory of Open Access Journals (Sweden)

    Tae Hee Hong


    Full Text Available Venoarterial extracorporeal membrane oxygenation (VA ECMO is widely used in patients with cardiogenic shock. Insufficient decompression of the left ventricle (LV is considered a major factor preventing adequate LV recovery. A 40-year-old male was diagnosed with acute myocardial infarction, and revascularization was performed using percutaneous stenting. However, cardiogenic shock occurred, and VA ECMO was initiated. Severe LV failure developed, and percutaneous transaortic catheter venting (TACV was incorporated into the venous circuit of VA ECMO under transthoracic echocardiography guidance. The patient was successfully weaned from VA ECMO. Percutaneous TACV is an effective, relatively noninvasive, and rapid method of LV decompression in patients undergoing VA ECMO.

  5. Microvascular decompression for the patient with painful tic convulsif after Bell palsy. (United States)

    Jiao, Wei; Zhong, Jun; Sun, Hui; Zhu, Jin; Zhou, Qiu-Meng; Yang, Xiao-Sheng; Li, Shi-Ting


    Painful tic convulsif is referred to as the concurrent trigeminal neuralgia and hemifacial spasm. However, painful tic convulsif after ipsilateral Bell palsy has never been reported before. We report a case of a 77-year-old woman with coexistent trigeminal neuralgia and hemifacial spasm who had experienced Bell palsy half a year ago. The patient underwent microvascular decompression. Intraoperatively, the vertebrobasilar artery was found to deviate to the symptomatic side and a severe adhesion was observed in the cerebellopontine angle. Meanwhile, an ectatic anterior inferior cerebellar artery and 2 branches of the superior cerebellar artery were identified to compress the caudal root entry zone (REZ) of the VII nerve and the rostroventral cisternal portion of the V nerve, respectively. Postoperatively, the symptoms of spasm ceased immediately and the pain disappeared within 3 months. In this article, the pathogenesis of the patient's illness was discussed and it was assumed that the adhesions developed from inflammatory reactions after Bell palsy and the anatomic features of the patient were the factors that generated the disorder. Microvascular decompression surgery is the suggested treatment of the disease, and the dissection should be started from the caudal cranial nerves while performing the operation.

  6. Spinal Epidural Hematoma after Thoracolumbar Posterior Fusion Surgery without Decompression for Thoracic Vertebral Fracture

    Directory of Open Access Journals (Sweden)

    Tsuyoki Minato


    Full Text Available We present a rare case of spinal epidural hematoma (SEH after thoracolumbar posterior fusion without decompression surgery for a thoracic vertebral fracture. A 42-year-old man was hospitalized for a thoracic vertebral fracture caused by being sandwiched against his back on broken concrete block. Computed tomography revealed a T12 dislocation fracture of AO type B2, multiple bilateral rib fractures, and a right hemopneumothorax. Four days after the injury, in order to promote early orthostasis and to improve respiratory status, we performed thoracolumbar posterior fusion surgery without decompression; the patient had back pain but no neurological deficits. Three hours after surgery, he complained of acute pain and severe weakness of his bilateral lower extremities; with allodynia below the level of his umbilicus, postoperative SEH was diagnosed. We performed immediate revision surgery. After removal of the hematoma, his symptoms improved gradually, and he was discharged ambulatory one month after revision surgery. Through experience of this case, we should strongly consider the possibility of preexisting SEH before surgery, even in patients with no neurological deficits. We should also consider perioperative coagulopathy in patients with multiple trauma, as in this case.

  7. Magnetic resonance imaging criteria of successful core decompression in avascular necrosis of the hip

    Energy Technology Data Exchange (ETDEWEB)

    Radke, S.; Kirschner, S.; Seipel, V.; Rader, C.; Eulert, J. [Department of Orthopaedic Surgery, Koenig-Ludwig-Haus, Julius-Maximilians University, Wuerzburg, Brettreichstr.11, 97074, Wuerzburg (Germany)


    To identify imaging criteria that determine the outcome of core decompression (CD) in femoral-head avascular necrosis (AVN). Radiographs and magnetic resonance imaging (MRI) of 65 hips with early stage AVN treated by core decompression between January 1990 and December 2000 for AVN were reviewed. All hips were categorized into two groups according to the result of CD using total hip arthroplasty (THA) as an end point. Hips that had no THA at follow-up were allocated to group I; those treated with a THA were allocated to group II. CD results were calculated for each group using THA as an end point. The parameters analyzed were the presence or absence of edema associated with the double-line sign on the preoperative MRI, the type of epiphyseal scar (ES) according to Jing, and the type of necrosis according to Mitchell. On follow-up, 45 hips had no THA (group I); 20 patients had a THA (group II). Patients with a radiographic crescent sign and those with edema associated with the double-line sign progressed to THA significantly more frequently. The extent of the necrosis had less discriminatory effect between the two groups. ES and necrotic tissue types had no prognostic value. In regard to the success of CD, it is important to differentiate on MRI between a double line sign plus bone marrow edema and a double-line sign only. (orig.)

  8. Continuous decompression with intramedullary nailing for the treatment of unicameral bone cysts. (United States)

    Masquijo, Julio Javier; Baroni, Eduardo; Miscione, Horacio


    To evaluate the efficacy of decompression of unicameral bone cysts (UBCs) of the long bones with intramedullary nailing and to compare responses to treatment according to location. We evaluated 48 consecutive patients treated between January 1988 and June 2000. Mean age was 10.3 years. Mean follow-up was 9.8 years. Evaluation was performed according to the radiographic criteria of Capanna. UBCs were located in the proximal humerus (n = 24), humeral shaft (n = 2), proximal femur (n = 19), distal tibia (n = 2) and fibula (n = 1). A total of 62.5% presented a pathological fracture. Successful results were observed in 89.5% (26 total healing, 17 healing with residual radiolucent areas), and there were four recurrences and, in one case, no response to treatment. There was more healing in the humerus than in the femur (92.3% versus 84.2%), and more tendency to restitution ad integrum, although the difference was not statistically significant (P = 0.1499). Intramedullary nailing is a minimally invasive method, which permits early stability and decompresses the cyst allowing healing. Significant differences were not observed among results from different locations.

  9. Compression and decompression of digital seismic waveform data for storage and communication

    International Nuclear Information System (INIS)

    Bhadauria, Y.S.; Kumar, Vijai


    Two different classes of data compression schemes, namely physical data compression schemes and logical data compression schemes are examined for their use in storage and communication of digital seismic waveform data. In physical data compression schemes, the physical size of the waveform is reduced. One, therefore, gets only a broad picture of the original waveform, when the data are retrieved and the waveform is reconstituted. Coerrelation between original and decompressed waveform varies inversely with the data compresion ratio. In the logical data compression schemes, the data are stored in a logically encoded form. Storage of unnecessary characters like blank space is avoided. On decompression original data are retrieved and compression error is nil. Three algorithms of logical data compression schemes have been developed and studied. These are : 1) optimum formatting schemes, 2) differential bit reduction scheme, and 3) six bit compression scheme. Results of the above three algorithms of logical compression class are compared with those of physical compression schemes reported in literature. It is found that for all types of data, six bit compression scheme gives the highest value of data compression ratio. (author). 6 refs., 8 figs., 1 appendix, 2 tabs

  10. Bunch decompression for laser-plasma driven free-electron laser demonstration schemes

    Directory of Open Access Journals (Sweden)

    T. Seggebrock


    Full Text Available X-ray free-electron lasers (FELs require a very high electron beam quality in terms of emittance and energy spread. Since 2004 high quality electrons produced by laser-wakefield accelerators have been demonstrated, but the electron quality up to now did not allow the operation of a compact x-ray FEL using these electrons. Maier et al. [Phys. Rev. X 2, 031019 (2012PRXHAE2160-330810.1103/PhysRevX.2.031019] suggested a concept for a proof-of-principle experiment allowing FEL operation in the vacuum ultraviolet range based on an optimized undulator and bunch decompression using electron bunches from a laser-plasma accelerator as currently available. In this paper we discuss in more detail how a chicane can be used as a bunch stretcher instead of a bunch compressor to allow the operation of a laser-wakefield accelerator driven FEL using currently available electrons. A scaling characterizing the impact of bunch decompression on the gain length is derived and the feasibility of the concept is tested numerically in a demanding scenario.

  11. Endoscopic foraminal decompression for failed back surgery syndrome under local anesthesia. (United States)

    Yeung, Anthony; Gore, Satishchandra


    The most common causes of failed back surgery are residual or recurrent herniation, foraminal fibrosis and foraminal stenosis that is ignored, untreated, or undertreated. Residual back ache may also be from facetal causes or denervation and scarring of the paraspinal muscles.(1-6) The original surgeon may advise his patient that nothing more can be done on the basis of his opinion that the nerve was visually decompressed by the original surgery, supported by improved post-op imaging and follow-up studies such as EMG and conduction velocity studies. Post-op imaging or electrophysiological assessment may be inadequate to explain all the reasons for residual or recurrent symptoms. Treatment of Failed back surgery by repeat traditional open revision surgery usually incorporates more extensive decompression causing increased instability and back pain, therefore necessitating fusion. The authors, having limited their practice to endoscopic MIS surgery over the last 15-20 years, report on their experience gained during that period to relieve pain by endoscopically visualizing and treating unrecognized causative patho-anatomy in FBSS.(7.) Thirty consecutive patients with FBSS presenting with back and leg pain that had supporting imaging diagnosis of lateral stenosis and /or residual / recurrent disc herniation, or whose pain complaint was supported by relief from diagnostic and therapeutic injections (Figure 1), were offered percutaneous transforaminal endoscopic discectomy and foraminoplasty over a repeat open procedure. Each patient sought consultation following a transient successful, partially successful or unsuccessful open translaminar surgical treatment for disc herniation or spinal stenosis. Endoscopic foraminoplasty was also performed to either decompress the bony foramen for foraminal stenosis, or foraminoplasty to allow for endoscopic visual examination of the affected traversing and exiting nerve roots in the axilla, also known as the "hidden zone" of Macnab

  12. Perforation and bacterial contamination of microscope covers in lumbar spinal decompressive surgery. (United States)

    Osterhoff, Georg; Spirig, José; Klasen, Jürgen; Kuster, Stefan P; Zinkernagel, Annelies S; Sax, Hugo; Min, Kan


    To determine the integrity of microscope covers and bacterial contamination at the end of lumbar spinal decompressive surgery. A prospective study of 25 consecutive lumbar spinal decompressions with the use of a surgical microscope was performed. For detection of perforations, the microscope covers were filled with water at the end of surgery and the presence of water leakage in 3 zones (objective, ocular and control panel) was examined. For detection of bacterial contamination, swabs were taken from the covers at the same locations before and after surgery. Among the 25 covers, 1 (4%) perforation was observed and no association between perforation and bacterial contamination was seen; 3 (4%) of 75 smears from the 25 covers showed post-operative bacterial contamination, i.e. 2 in the ocular zone and 1 in the optical zone, without a cover perforation. The incidence of microscope cover perforation was very low and was not shown to be associated with bacterial contamination. External sources of bacterial contamination seem to outweigh the problem of contamination due to failure of cover integrity. © 2014 S. Karger AG, Basel.

  13. Magnetic resonance imaging criteria of successful core decompression in avascular necrosis of the hip

    International Nuclear Information System (INIS)

    Radke, S.; Kirschner, S.; Seipel, V.; Rader, C.; Eulert, J.


    To identify imaging criteria that determine the outcome of core decompression (CD) in femoral-head avascular necrosis (AVN). Radiographs and magnetic resonance imaging (MRI) of 65 hips with early stage AVN treated by core decompression between January 1990 and December 2000 for AVN were reviewed. All hips were categorized into two groups according to the result of CD using total hip arthroplasty (THA) as an end point. Hips that had no THA at follow-up were allocated to group I; those treated with a THA were allocated to group II. CD results were calculated for each group using THA as an end point. The parameters analyzed were the presence or absence of edema associated with the double-line sign on the preoperative MRI, the type of epiphyseal scar (ES) according to Jing, and the type of necrosis according to Mitchell. On follow-up, 45 hips had no THA (group I); 20 patients had a THA (group II). Patients with a radiographic crescent sign and those with edema associated with the double-line sign progressed to THA significantly more frequently. The extent of the necrosis had less discriminatory effect between the two groups. ES and necrotic tissue types had no prognostic value. In regard to the success of CD, it is important to differentiate on MRI between a double line sign plus bone marrow edema and a double-line sign only. (orig.)

  14. Phrenic nerve decompression for the management of unilateral diaphragmatic paralysis - preoperative evaluation and operative technique. (United States)

    Hoshide, Reid; Brown, Justin


    Unilateral diaphragmatic paralysis (UDP) can be a very disabling, typically causing shortness of breath and reduced exercise tolerance. We present a case of a surgical decompression of the phrenic nerve of a patient who presented with UDP, which occurred following cervical spine surgery. The workup for the etiology of UDP demonstrated paradoxical movement on "sniff test" and notably impaired pulmonary function tests. Seven months following the onset of the UDP, he underwent a surgical decompression of the phrenic nerve at the level of the anterior scalene. He noted rapid symptomatic improvement following surgery and reversal of the above noted objective findings was documented. At his 4-year follow-up, he had complete resolution of his clinical symptoms. Repeated physiologic testing of his respiratory function had shown a complete reversal of his UDP. Anatomical compression of the phrenic nerve by redundant neck vasculature should be considered in the differential diagnosis of UDP. Here we demonstrated the techniques in workup and surgical management, with both subjective and objective evidence of success.

  15. Phrenic nerve decompression for the management of unilateral diaphragmatic paralysis – preoperative evaluation and operative technique (United States)

    Hoshide, Reid; Brown, Justin


    Background: Unilateral diaphragmatic paralysis (UDP) can be a very disabling, typically causing shortness of breath and reduced exercise tolerance. We present a case of a surgical decompression of the phrenic nerve of a patient who presented with UDP, which occurred following cervical spine surgery. Methods: The workup for the etiology of UDP demonstrated paradoxical movement on “sniff test” and notably impaired pulmonary function tests. Seven months following the onset of the UDP, he underwent a surgical decompression of the phrenic nerve at the level of the anterior scalene. Results: He noted rapid symptomatic improvement following surgery and reversal of the above noted objective findings was documented. At his 4-year follow-up, he had complete resolution of his clinical symptoms. Repeated physiologic testing of his respiratory function had shown a complete reversal of his UDP. Conclusions: Anatomical compression of the phrenic nerve by redundant neck vasculature should be considered in the differential diagnosis of UDP. Here we demonstrated the techniques in workup and surgical management, with both subjective and objective evidence of success. PMID:29184705

  16. Visualization and void fraction measurement of decompressed boiling flow in a capillary tube

    International Nuclear Information System (INIS)

    Asano, H.; Murakawa, H.; Takenaka, N.; Takiguchi, K.; Okamoto, M.; Tsuchiya, T.; Kitaide, Y.; Maruyama, N.


    A capillary tube is often used as a throttle for a refrigerating cycle. Subcooled refrigerant usually flows from a condenser into the capillary tube. Then, the refrigerant is decompressed along the capillary tube. When the static pressure falls below the saturation pressure for the liquid temperature, spontaneous boiling occurs. A vapor-liquid two-phase mixture is discharged from the tube. In designing a capillary tube, it is necessary to calculate the flow rate for given boundary conditions on pressure and temperature at the inlet and exit. Since total pressure loss is dominated by frictional and acceleration losses during two-phase flow, it is first necessary to specify the boiling inception point. However, there will be a delay in boiling inception during decompressed flow. This study aimed to clarify the boiling inception point and two-phase flow characteristics of refrigerant in a capillary tube. Refrigerant flows in a coiled copper capillary tube were visualized by neutron radiography. The one-dimensional distribution of volumetric average void fraction was measured from radiographs through image processing. From the void fraction distribution, the boiling inception point was determined. Moreover, a simplified CT method was successfully applied to a radiograph for cross-sectional measurements. The experimental results show the flow pattern transition from intermittent flow to annular flow that occurred at a void fraction of about 0.45.

  17. Single-stage transforaminal decompression, debridement, interbody fusion, and posterior instrumentation for lumbosacral brucellosis. (United States)

    Abulizi, Yakefu; Liang, Wei-Dong; Muheremu, Aikeremujiang; Maimaiti, Maierdan; Sheng, Wei-Bin


    Spinal brucellosis is a less commonly reported infectious spinal pathology. There are few reports regarding the surgical treatment of spinal brucellosis in existing literature. This retrospective study was conducted to determine the effectiveness of single-stage transforaminal decompression, debridement, interbody fusion, and posterior instrumentation for lumbosacral spinal brucellosis. From February 2012 to April 2015, 32 consecutive patients (19 males and 13 females, mean age 53.7 ± 8.7) with lumbosacral brucellosis treated by transforaminal decompression, debridement, interbody fusion, and posterior instrumentation were enrolled. Medical records, imaging studies, laboratory data were collected and summarized. Surgical outcomes were evaluated based on visual analogue scale (VAS), Oswestry Disability Index (ODI) and Japanese Orthopaedic Association (JOA) scale. The changes in C-reactive protein (CRP) levels, erythrocyte sedimentation rate (ESR), clinical symptoms and complications were investigated. Graft fusion was evaluated using Bridwell grading criteria. The mean follow-up period was 24.9 ± 8.2 months. Back pain and radiating leg pain was relieved significantly in all patients after operation. No implant failures were observed in any patients. Wound infection was observed in two patients and sinus formation was observed in one patient. Solid bony fusion was achieved in 30 patients and the fusion rate was 93.8%. The levels of ESR and CRP were returned to normal by the end of three months' follow-up. VAS and ODI scores were significantly improved (P brucellosis.

  18. Decompression Theory. (United States)


    vessel- rich group, a vessel-poor group, a fatty group, and so on ( Papper and Kitz 1963). Behnke’s original suggestion, put forth in the first...An examination of the critical released volume concept in decom- pression sickness. Proc. Roy. Soc. Lond. B. 197:299-313, 1977. Papper , E.M., and R.J

  19. [Quality of Life and Functional Outcome after Microsurgical Decompression in Lumbar Spinal Stenosis: a Register Study]. (United States)

    Zarghooni, Kourosh; Beyer, Frank; Papadaki, Joanna; Boese, Christoph Kolja; Siewe, Jan; Schiffer, Gereon; Eysel, Peer; Bredow, Jan


    Introduction Because of recent increases in life expectancy, lumbar spinal stenosis (LSS) has become one of the most common degenerative changes in the spine. In patients not responding to conservative therapy, microsurgical decompression is the gold standard of operative treatment for degenerative LSS. The goal of the current study is to evaluate quality of life after microsurgical decompression for LSS, using data from the DWG Register (previously Spine Tango). Methods 36 patients were included in this single-center, prospective, observational study from January 2013 to June 2014. Data were collected from the Spine Tango or DWG Register. The core outcome measure index (COMI), Oswestry Disability Index (ODI), and the quality of life questionnaire EuroQoL-5D were used. Data were collected prior to surgery as well as six weeks, six months, and twelve months after the operation. Results The patient cohort comprised 13 females and 23 males (36.1 and 63.9 %). Complete 12-month follow-up data on 21 patients were available for analysis. Compared to preoperative measures, the COMI score increased 8.1 ± 1.5 over the entire follow up, with 4.5 ± 3.1 at 6 weeks (p < 0.001), 4.8 ± 3.1 at 6 months, and 3.8 ± 3.2 at 12 months. ODI scores, measuring spinal function impairment, were significantly better than preoperative values overall (47.5 ± 17.3) and after 6 weeks (29.1 ± 22.4; p < 0.005), 6 months (30.0 ± 19.3), and 12 months (23.8 ± 18.2). Quality of life measures improved in a similar manner (preoperative: 0.36 ± 0.38; 6 weeks: 0.57 ± 0.34 (p < 0.019); 6 months: 0.62 ± 0.28; 12 months: 0.67 ± 0.31). Conclusion Our study shows that LSS patients without previous surgery and neurologic deficits can expect significant pain relief and improved quality of life already six weeks after undergoing stabilizing decompression. There was an increase in positive postoperative effects over 12 months. The DWG

  20. Decompression Induced Crystallization of Basaltic Andesite Magma: Constraints on the Eruption of Arenal Volcano, Costa Rica. (United States)

    Szramek, L. A.; Gardner, J. E.; Larsen, J. F.


    Arenal Volcano is a small stratovolcano located 90 km NW of San Jose, Costa Rica. In 1968 current activity began with a Plinian phase, and has continued to erupt lava flows and pyroclastic flows intermittently since. Samples from the Plinian, pyroclastic flow, strombolian, and effusive phases have been studied texturally. Little variation in crystallinity occurs amongst the different phases. Number density of crystals, both 2D and 3D are 50-70 mm-2 and 30,000-50,000 mm-3 in the Plinian sample, compared to the lesser values in other eruptive types. Characteristic crystal size also increases as explosivity decreases. Two samples, both lava flows collected while warm, overlap with the Plinian sample. This suggests that the variations seen may be a result of cooling history. Plagioclase differs between the Plinian sample, in which they are only tabular in shape, and the other eruptive types, which contain both tabular and equant crystals. To link decompression paths of the Arenal magma to possible pre-eruptive conditions, we have carried out hydrothermal experiments. The experiments were preformed in TZM pressure vessels buffered at a fugacity of Ni-NiO and water saturation. Phase equilibria results in conjunction with mineral compositions and temperature estimates by previous workers from active lava flows and two-pyroxene geothermometry, constrain the likely pre-eruptive conditions for the Arenal magma to 950-1040° C with a water pressure of 50-80 MPa. Samples that started from conditions that bracket our estimated pre-eruptive conditions were decompressed in steps of 5-30 MPa and held for various times at each step until 20 MPa was reached, approximating average decompression rates of 0.25, 0.025, 0.0013 MPa/s. Comparison of textures found in the natural samples to the experimentally produced textures suggest that the Plinian eruption likely was fed by magma ascending at 0.05-1 m/s, whereas the less explosive phases were fed by magma ascending at 0.05 m/s or less.

  1. Sural artery perforator flap with posterior tibial neurovascular decompression for recurrent foot ulcer in leprosy patients

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    Ismail, Hossam El-din Ali


    Full Text Available Introduction: The sensory loss and alteration of the shape of the foot make the foot liable to trauma and pressure, and subsequently cause more callus formation, blisters, and ulcers. Foot ulcers usually are liable to secondary infection as cellulitis or osteomyelitis, and may result in amputations. Foot ulcers are a major problem and a major cause of handicaps in leprosy patients. The current study is to present our clinical experience and evaluate the use of sural flap with posterior tibial neurovascular decompression (PTND in recurrent foot ulcers in leprosy patients.Patient and methods: A total number of 9 patients were suffering from chronic sequelae of leprosy as recurrent foot ulcers. All the patients were reconstructed with the reverse sural artery fasciocutaneous flap with posterior tibial neurovascular decompression from September 2012 to August 2015. Six patients were male and three were female with a mean age of 39.8 years (range, 30–50 years. All the soft tissue defects were in the weight-bearing area of the inside of the foot. The flap sizes ranged from 15/4 to 18/6 cm. Mean follow-up period was 21.2 months (range, 35–2 months.Results: All the flaps healed uneventfully. There was no major complication as total flap necrosis. Only minor complications occurred which were treated without surgical intervention except in two patients who developed superficial necrosis of the skin paddle. Surgical debridement was done one week later. The flap was completely viable after surgery, and the contour of the foot was restored. We found that an improvement of sensation occurred in those patients in whom the anesthesia started one year ago or less and no sensory recovery in patient in whom the anesthesia had lasted for more than two years.Conclusion: The reverse sural artery flap with posterior tibial neurovascular decompression provides a reliable method for recurrent foot soft tissue reconstruction in leprosy patients with encouraging

  2. Joint pain and Doppler-detectable bubbles in altitude (Hypobaric) decompression (United States)

    Powell, Michael R.


    The observation that altitude decompression sickness (DCS) is associated with pain in the lower extremities is not new, although it is not a consistent finding. DCS in divers is generally in the upper body, an effect often attributed to non-loading of the body while immersed. In caisson workers, DCS is reported more in the lower extremities. Surprisingly, many researchers do not mention the location of DCS joint pain, apparently considering it to be random. This is not the case for the tissue ratios encountered in studying decompression associated with simulated EVA. In NASA/JSC tests, altitude DCS generally presented first in either the ankle, knee, or hip (83 percent = 73/88). There was a definite statistical relation between the maximum Spencer precordial Doppler Grade and the incidence of DCS in the extremity, although this is not meant to imply a casual relation between circulating gas bubbles and joint pain. The risk of DCS with Grade 4 was considerably higher than that of Grades 0 to 3. The DCS risk was independent of the 'tissue ratio.' There was a predominance of lower extremity DCS even when exercise was performed with the upper body. The reason for these locations we hypothesize to be attributed to the formation of tissue gas micronuclei from kinetic and tensile forces (stress-assisted nucleation) and are the result of the individuals ambulating in a 1g environment. Additionally, since these showers of Doppler bubbles can persist for hours, it is difficult to imagine that they are emanating solely from tendons and ligaments, the supposed site of joint pain. This follows from Henry's law linking the volume of joint tissue (the solvent) and the solubility coefficient of inert gas; there is volumetrically insufficient connective tissue to produce the prolonged release of gas bubbles. If gas bubbles are spawned and released from connective tissue, their volume is increased by those from muscle tissue. Therefore, the nexus between Doppler-detectable gas

  3. Remote multiple intracranial hemorrhage in multiple metastatic lung adenocarcinoma following decompression of posterior fossa lesion: Unknown cause

    Directory of Open Access Journals (Sweden)

    Subhas Konar


    Full Text Available Cerebral metastasis can present with hemorrhage. However, multiple hemorrhages in metastatic lesions following surgical decompression of a single lesion are never reported. We report a case of cerebral metastasis from lung cancer that developed multiple hemorrhages in supratentorial metastatic lesions following surgical resection of an infratentorial lesion.

  4. Effectiveness of Standardized Physiotherapy Exercises for Patients With Difficulty Returning to Usual Activities After Decompression Surgery for Subacromial Impingement Syndrome

    DEFF Research Database (Denmark)

    Christiansen, David Høyrup; Frost, Poul; Falla, Deborah


    BACKGROUND: Little is known about the effectiveness of exercise programs after decompression surgery for subacromial impingement syndrome. For patients with difficulty returning to usual activities, special efforts may be needed to improve shoulder function. OBJECTIVE: The purpose of this study w...

  5. Non-surgical spinal decompression therapy: does the scientific literature support efficacy claims made in the advertising media?

    Directory of Open Access Journals (Sweden)

    Daniel Dwain M


    Full Text Available Abstract Background Traction therapy has been utilized in the treatment of low back pain for decades. The most recent incarnation of traction therapy is non-surgical spinal decompression therapy which can cost over $100,000. This form of therapy has been heavily marketed to manual therapy professions and subsequently to the consumer. The purpose of this paper is to initiate a debate pertaining to the relationship between marketing claims and the scientific literature on non-surgical spinal decompression. Discussion Only one small randomized controlled trial and several lower level efficacy studies have been performed on spinal decompression therapy. In general the quality of these studies is questionable. Many of the studies were performed using the VAX-D® unit which places the patient in a prone position. Often companies utilize this research for their marketing although their units place the patient in the supine position. Summary Only limited evidence is available to warrant the routine use of non-surgical spinal decompression, particularly when many other well investigated, less expensive alternatives are available.

  6. Surgical Decompression for Space-Occupying Cerebral Infarction: Outcomes at 3 Years in the Randomized HAMLET Trial

    NARCIS (Netherlands)

    Geurts, Marjolein; van der Worp, H. Bart; Kappelle, L. Jaap; Amelink, C. Johan; Algra, Ale; Hofmeijer, Jeannette


    Background and Purpose—We assessed whether the effects of surgical decompression for space-occupying hemispheric infarction, observed at 1 year, are sustained at 3 years. Methods—Patients with space-occupying hemispheric infarction, who were enrolled in the Hemicraniectomy After Middle cerebral

  7. Evaluation of transcranial surgical decompression of the optic canal as a treatment option for traumatic optic neuropathy. (United States)

    He, Zhenhua; Li, Qiang; Yuan, Jingmin; Zhang, Xinding; Gao, Ruiping; Han, Yanming; Yang, Wenzhen; Shi, Xuefeng; Lan, Zhengbo


    Traumatic optic neuropathy (TON) is a serious complication of head trauma, with the incidence rate ranging from 0.5% to 5%. The two treatment options widely practiced for TON are: (i) high-dose corticosteroid therapy and (ii) surgical decompression. However, till date, there is no consensus on the treatment protocol. This study aimed to evaluate the therapeutic efficacy of transcranial decompression of optic canal in TON patients. A total of 39 patients with visual loss resulting from TON between January 2005 and June 2013 were retrospectively reviewed for preoperative vision, preoperative image, visual evoked potential (VEP), surgical approach, postoperative visual acuity, complications, and follow-up results. All these patients underwent transcranial decompression of optic canal. During the three-month follow-up period, among the 39 patients, 21 showed an improvement in their eyesight, 6 recovered to standard logarithmic visual acuity chart "visible," 10 could count fingers, 2 could see hand movement, and 3 regained light sensation. Visual evoked potential could be used as an important preoperative and prognostic evaluation parameter for TON patients. Once TON was diagnosed, surgery is a promising therapeutic option, especially when a VEP wave is detected, irrespective of the HRCT scan findings. Operative time between trauma and operation is not necessary reference to assess the therapeutic effect of surgical decompression. The poor results of this procedure may be related to the severity of optic nerve injury. The patient's age is an important factor affecting the surgical outcomes. Copyright © 2015 Elsevier B.V. All rights reserved.

  8. Microsurgical Decompression of the Cochlear Nerve to Treat Disabling Tinnitus via an Endoscope-Assisted Retrosigmoid Approach: The Padua Experience. (United States)

    Di Stadio, Arianna; Colangeli, Roberta; Dipietro, Laura; Martini, Alessandro; Parrino, Daniela; Nardello, Ennio; D'Avella, Domenico; Zanoletti, Elisabetta


    The use of surgical cochlear nerve decompression is controversial. This study aimed at investigating the safety and validity of microsurgical decompression via an endoscope-assisted retrosigmoid approach to treat tinnitus in patients with neurovascular compression of the cochlear nerve. Three patients with disabling tinnitus resulting from a loop in the internal auditory canal were evaluated with magnetic resonance imaging and tests of pure tone auditory, tinnitus, and auditory brain response (ABR) to identify the features of the cochlear nerve involvement. We observed a loop with a caliber greater than 0.8 mm in all patients. Patients were treated via an endoscope-assisted retrosigmoid microsurgical decompression. After surgery, none of the patients reported short-term or long-term complications. After surgery, tinnitus resolved immediately in 2 patients, whereas in the other patient symptoms persisted although they improved; in all patients, hearing was preserved and ABR improved. Microsurgical decompression via endoscope-assisted retrosigmoid approach is a promising, safe, and valid procedure for treating tinnitus caused by cochlear nerve compression. This procedure should be considered in patients with disabling tinnitus who have altered ABR and a loop that has a caliber greater than 0.8 mm and is in contact with the cochlear nerve. Copyright © 2018 Elsevier Inc. All rights reserved.

  9. Results of treatment in patients with non traumatic avascular necrosis of the femoral head by monitor assisted core decompression

    International Nuclear Information System (INIS)

    Piperovski, T.


    The authors tried to evaluate the results of treatment in 32 patients (39 hips) with non-traumatic avascular necrosis (AVN) of the femoral head by monitor assisted core decompression. Average age - 44 years, 19 were male and 13 female. 7 patients had bilateral involvement. The diagnosis AVN has been made by anteroposterior and lateral conventional radiographs bone scintigraphy and MRI. It is also done histopathological examinations of the specimens taken during the operation in order to confirm the primary diagnosis. It is established early diagnosis in stage I, stage IIA and IIB (the modified staging system of Ficat and Arlet is used, in combination with the system of Steinberg at al.) All patients have been treated by core decompression. The operative technique used is modified Phemister, which is similar to Ficat- Arlet. After the operation periodically x-ray and MRI investigations are done. The mean follow up time is 4 years. 79.37% of the hips showed radiographic and MRI stabilization within 2-4 years after core decompression. In 10.25% the results are moderate and in the rest (10.25%) total or bi-polar hip prosthesis have been implanted. The benefit of core decompression in patients with non-traumatic avascular necrosis of the femoral head is justified

  10. Postural stability in patients with decompression sickness evaluated by means of Quantitative Romberg testing

    DEFF Research Database (Denmark)

    Hedetoft, Morten; Hyldegaard, Ole


    obtained with the Quantitative Romberg test were observed in the group of DCS with vertigo relative to DCS without vertigo and healthy controls. A stepwise improvement in postural instability for DCS patients with vertigo was found following HBO2 therapy. After three treatments of HBO2, postural stability...... was found to be within the normal range of healthy controls. CONCLUSIONS: The Quantitative Romberg test offers the the clinician a fast, reliable and objective set of parametrical data to document postural instability in patients with either confirmed or suspected DCS.......OBJECTIVE: The present study was designed to retrospectively evaluate the use of quantitative Romberg's testing on postural stability during the course of hyperbaric oxygen (HBO2) therapy in patients presenting with decompression sickness (DCS). METHODS: The Quantitative Romberg test was used...

  11. The influence of decompressive craniectomy on the development of hydrocephalus: a review

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    Jun Ding


    Full Text Available Decompressive craniectomy (DC is widely used to treat intracranial hypertension following traumatic brain injury (TBI or cerebral vascular disease. Many studies have discussed complications of this procedure, and hydrocephalus is a common complication of DC. To further evaluate the relationship between DC and hydrocephalus, a review of the literature was performed. Numerous complications may arise after DC, including contusion or hematoma expansion, epilepsy, herniation of the cortex through a bone defect, CSF leakage through the scalp incision, infection, subdural effusion, hydrocephalus and “syndrome of the trephined”. Several hydrocephalus predictors were identified; these included DC, distance from the midline, hygroma, age, injury severity, subarachnoid or intraventricular hemorrhage, delayed time to craniotomy, repeated operation, and duraplasity. However, results differed among studies. The impact of DC on hydrocephalus remains controversial.

  12. Modified lateral orbital wall decompression in Graves' orbitopathy using computer-assisted planning. (United States)

    Spalthoff, S; Jehn, P; Zimmerer, R; Rana, M; Gellrich, N-C; Dittmann, J


    Graves' orbitopathy, a condition seen in the autoimmune syndrome Graves' disease, affects the fatty tissue and muscles inside the orbit. Graves' orbitopathy is associated with increasing exophthalmos and sometimes leads to compressive dysthyroid optic neuropathy, resulting in progressive vision loss. Dysthyroid compressive optic neuropathy, functional problems, and cosmetic problems are the main indications for surgical decompression of the orbit, especially if conservative treatment has not led to a reduction in symptoms. Many surgical techniques are described in the literature. This article presents a modification of the lateral orbital wall osteotomy, involving the rotation and reduction of the osteotomized bone segment using preoperative planning, intraoperative computed navigation, and piezoelectric surgery. This new method combines the advantages of different techniques and appears to be a valid approach to the treatment of severe cases of Graves' orbitopathy. Copyright © 2017 International Association of Oral and Maxillofacial Surgeons. Published by Elsevier Ltd. All rights reserved.

  13. Foramen magnum decompression versus terminal ventriculostomy for the treatment of syringomyelia. (United States)

    Filizzolo, F; Versari, P; D'Aliberti, G; Arena, O; Scotti, G; Mariani, C


    The A.A review 30 consecutive cases of syringomyelia operated on during the last seven years. Six terminal ventriculostomies (TV) and twenty-seven procedures for foramen magnum decompression (FMD) were performed. All patients of TV group had CT-myelography (CTM) and/or NMR controls at different times after surgery. Clinical results are as follows: 1) of the 6 patients who had TV, only one showed an improvement while five continued to deteriorate and three of them needed a FMD, one a cysto-peritoneal shunt and the last one died from lung cancer. 2) of the 27 patients who had FMD, twenty improved, four were unchanged and three worsened. 3) no surgical deaths occurred in this series. Postoperative NMR monitoring represents an effective non-invasive neuroradiological procedure that allows follow-up of syrinx evolution over the years.

  14. Surgical results and MRI findings of cervical myelopathy treated with anterior decompression and fusion

    International Nuclear Information System (INIS)

    Miyazato, Takenari; Teruya, Yoshimitsu; Kinjo, Yukio


    We reviewed 19 patients with cervical myelopathy treated with anterior decompression and fusion. Etiology of cervical myelopathy was cervical disc herniation (CDH) in 13 patients and cervical spondylosis (CSM) in 6. Clinical recovery rate (%) was calculated from preoperative cervical myelopathy score (JOA) and the score at follow-up. Correlation between the clinical recovery rate and MRI findings (area and flatness at the narrowest part of the spinal cord), age at surgery, duration of myelopathy and pre-operative clinical score were analyzed separately in the CDH and CSM groups. Clinical recovery rate averaged 69% in the CDH group and 75% in the CSM group. In the CDH group, average clinical recovery rate in patients younger than 60 years was 80 and in patients over 60 years was 60. There was a significant negative correlation between the clinical recovery rate and age at surgery (p<0.05). No significant correlation was found between the clinical recovery rate and other factors investigated. (author)

  15. An abrupt outgassing revealed by a slow decompression experiment of cristal-bearing syrup foam (United States)

    Kanno, Y.; Namiki, A.


    Distribution of volcanic gasses in a conduit determines eruption style. Outgassing changes the distribution of volcanic gasses in a conduit.We here simulated the outgassing from ascending magma by slow decompression experiments. As molten magma ascends in a conduit, surrounding pressure becomes low and bubbles in magma expand. In our previous work, we found that the bubble expansion causes film rupturing and makes paths for outgassing. The crystals in magma may affect this newly found outgassing style. Accordingly, we slowly decompressed syrup foam including solid particles as a magma analogue. Experiments are conducted in an acrylic tank. We observed the expansion of three-phase magma analog from the front of the tank using a digital video camera. From the images and pressure measurements, we calculated time evolution of the syrup volume and permeability. We consider that there is no bubble segregation by the ascent of individual bubbles from the Stoke's velocity. We conducted our experiments with a viscosity range of 10-20 Pa s which is the same orders of magnitude of that of basaltic magma, 10-103 Pa s. At the beginning of the decompression, the volume change of the syrup foam is well explained by isothermal expansion. When the gas fractions reached to the 85-90%, we observed that deformations of bubble films caused film rupturing so that bubbles coalesce vertically to clear a path. As time elapsed, the measured gas volume in the foam becomes smaller than that estimated by the isothermal expansion, indicating the occurrence of outgassing. In the experiments with high volume fraction of solid particles (>30 vol.% for bubble-free liquid), we observed another new style of outgassing. Several large voids (> 10 mm in radius) appear at a middle height of the foam and connect each other to make a horizontally elongated cavity. The roof of the cavity collapses, and then massive outgassing occurs. At the beginning of the decompression until the foam collapses, outgassing

  16. Posterior fossa decompression with duraplasty in Chiari surgery: A technical note

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    Marcelo Ferreira Sabba

    Full Text Available Summary Chiari malformation (CM is the most common and prevalent symptomatic congenital craniocervical malformation. Radiological diagnosis is established when the cerebellar tonsils are located 5 mm or more below the level of the foramen magnum on magnetic resonance imaging (MRI. Surgical treatment is indicated whenever there is symptomatic tonsillar herniation or syringomyelia/hydrocephalus. The main surgical treatment for CM without craniocervical instability (such as atlantoaxial luxation is posterior fossa decompression, with or without duraplasty. The authors describe in details and in a stepwise fashion the surgical approach of patients with CM as performed at the State University of Campinas, emphasizing technical nuances for minimizing the risks of the procedure and potentially improving patient outcome.

  17. Decompressive craniotomy for the treatment of malignant infarction of the middle cerebral artery: mortality and outcome

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    Gianise Toboliski Bongiorni

    Full Text Available ABSTRACT Objective To assess, by Rankin scale, the functional disability of patients who had a malignant middle cerebral artery (MCA ischemic stroke, who underwent decompressive craniotomy (DC within the first 30 days. Methods A cross-sectional study in a University hospital. Between June 2007 and December 2014, we retrospectively analyzed the records of all patients submitted to DC due to a malignant MCA infarction. The mortality rate was defined during the hospitalization period. The modified outcome Rankin score (mRS was measured 30 days after the procedure, for stratification of the quality of life. Results The DC mortality rate was 30% (95% CI 14.5 to 51.9 for the 20 patients reported. The mRS 30 days postoperatively was ≥ 4 [3.3 to 6] for all patients thereafter. Conclusion DC is to be considered a real alternative for the treatment of patients with a malignant ischemic MCA infarction.

  18. Decompression illness in divers treated in Auckland, New Zealand, 1996-2012. (United States)

    Haas, Rachel M; Hannam, Jacqueline A; Sames, Christopher; Schmidt, Robert; Tyson, Andrew; Francombe, Marion; Richardson, Drew; Mitchell, Simon J


    The treatment of divers for decompression illness (DCI) in Auckland, New Zealand, has not been described since 1996, and subsequent trends in patient numbers and demographics are unmeasured. This was a retrospective audit of DCI cases requiring recompression in Auckland between 01 January 1996 and 31 December 2012. Data describing patient demographics, dive characteristics, presentation of DCI and outcomes were extracted from case notes and facility databases. Trends in annual case numbers were evaluated using Spearman's correlation coefficients (ρ) and compared with trends in entry-level diver certifications. Trends in patient demographics and delay between diving and recompression were evaluated using regression analyses. There were 520 DCI cases. Annual caseload decreased over the study period (ρ = 0.813, P Auckland have declined significantly over the last 17 years. The most plausible explanation is declining diving activity but improvements in diving safety cannot be excluded. The delay between diving and recompression has reduced.

  19. Pathological Fracture of Clavicle Following Sub-Acromial Decompression-Infraclavicular Compartment Syndrome?

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    S Mukhopadhyay


    Full Text Available A 34-year-old factory worker presented with pain and weakness of the left shoulder following a fall on ice on her left shoulder. An ultrasound scan of the shoulder taken 4 months after injury showed small partial articular surface tear of the supraspinatus tendon. Ten days following subacromial decompression she suffered a pathological fracture of her left clavicle. MRI, CT, and isotope bone scans showed no evidence of malignancy or infection but a collection of fluid was noted underlying the clavicle communicating to the acromioclavicular joint. Ultrasound scan guided aspiration of 20 millilitres of bloodstained fluid underlying the clavicle resulted in gradual recovery and adequate healing of the fracture.

  20. Magnetic Resonance Imaging in Breath-Hold Divers with Cerebral Decompression Sickness

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    Ryu Matsuo


    Full Text Available The mechanism of cerebral decompression sickness (DCS is still unclear. We report 2 cases of breath-hold divers with cerebral DCS in whom magnetic resonance imaging (MRI demonstrated distinctive characteristics. One case presented right hemiparesthesia, diplopia, and gait disturbance after breath-hold diving into the sea at a depth of 20 m. Brain MRI with fluid-attenuated inversion recovery (FLAIR sequence revealed multiple hyperintense lesions in the right frontal lobe, bilateral thalamus, pons, and right cerebellar hemisphere. The second case presented visual and gait disturbance after repetitive breath-hold diving into the sea. FLAIR imaging showed hyperintense areas in the bilateral occipito-parietal lobes. In both cases, diffusion-weighted imaging and apparent diffusion coefficient mapping revealed hyperintense areas in the lesions identified by FLAIR. Moreover, follow-up MRI showed attenuation of the FLAIR signal abnormalities. These findings are suggestive of transient hyperpermeability in the microvasculature as a possible cause of cerebral DCS.

  1. Cerebral microdialysis and PtiO2 to decide unilateral decompressive craniectomy after brain gunshot

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    Boret Henry


    Full Text Available Decompressive craniectomy (DC following brain injury can induce complications (hemorrhage, infection, and hygroma. It is then considered as a last-tier therapy, and can be deleteriously delayed. Focal neuromonitoring (microdialysis and PtiO2 can help clinicians to decide bedside to perform DC in case of intracranial pressure (ICP around 20 to 25 mmHg despite maximal medical treatment. This was the case of a hunter, brain injured by gunshot. DC was performed at day 6, because of unstable ICP, ischemic trend of PtiO2, and decreased cerebral glucose but normal lactate/pyruvate ratio. His evolution was good despite left hemiplegia due to initial injury.

  2. Microvascular Decompression for Treatment of Trigeminal Neuralgia in Patient with Facial Nerve Schwannoma. (United States)

    Marinelli, John P; Van Gompel, Jamie J; Link, Michael J; Carlson, Matthew L


    Secondary trigeminal neuralgia (TN) is uncommon. When a space-occupying lesion with mass effect is identified, the associated TN is often exclusively attributed to the tumor. This report illustrates the importance of considering coexistent actionable pathology when surgically treating secondary TN. A 51-year-old woman presented with abrupt-onset TN of the V2 and V3 nerve divisions with hypesthesia. She denied changes in hearing, balance, or facial nerve dysfunction. Magnetic resonance imaging revealed a 1.6-cm contrast-enhancing cerebellopontine angle tumor that effaced the trigeminal nerve, consistent with a vestibular schwannoma. In addition, a branch of the superior cerebellar artery abutted the cisternal segment of the trigeminal nerve on T2-weighted thin-slice magnetic resonance imaging. Intraoperative electrical stimulation of the tumor elicited a response from the facial nerve at low threshold over the entire accessible tumor surface, indicating that the tumor was a facial nerve schwannoma. Considering the patient's lack of facial nerve deficit and that the tumor exhibited no safe entry point for intracapsular debulking, tumor resection was not performed. Working between the tumor and tentorium, a branch of the superior cerebellar artery was identified and decompressed with a Teflon pad. At last follow-up, the patient exhibited resolution of her TN. Her hearing and facial nerve function remained intact. Despite obstruction from a medium-sized tumor, it is still possible to achieve microvascular decompression of the fifth cranial nerve. This emphasizes the importance of considering other actionable pathology during surgical management of presumed tumor-induced TN. Further, TN is relatively uncommon with medium-sized vestibular schwannomas and coexistent causes should be considered. Copyright © 2018 Elsevier Inc. All rights reserved.

  3. Surgical decompression of thoracic spinal stenosis in achondroplasia: indication and outcome. (United States)

    Vleggeert-Lankamp, Carmen; Peul, Wilco


    The achondroplastic spinal canal is narrow due to short pedicles and a small interpedicular distance. Compression of neural structures passing through this canal is therefore regularly encountered but rarely described. Symptomatology, radiological evaluation, and treatment of 20 patients with achondroplasia who underwent decompression of the thoracic spinal cord are described and outcome is correlated with the size of the spinal canal and the thoracolumbar kyphotic angle. Scores from the modified Japanese Orthopaedic Association scale, Nurick scale, European Myelopathy scale, Cooper myelopathy scale for lower extremities, and Odom criteria before and after surgery were compared. Magnetic resonance imaging was evaluated to determine the size of the spinal canal, spinal cord compression, and presence of myelomalacia. The thoracolumbar kyphotic angle was measured using fluoroscopy. Patient symptomatology included deterioration of walking pattern, pain, cramps, spasms, and incontinence. Magnetic resonance images of all patients demonstrated spinal cord compression due to degenerative changes. Surgery resulted in a slight improvement on all the ranking scales. Surgery at the wrong level occurred in 15% of cases, but no serious complications occurred. The mean thoracolumbar kyphotic angle was 20°, and no correlation was established between this angle and outcome after surgery. No postoperative increase in this angle was reported. There was also no correlation between size of the spinal canal and outcome. Decompressive surgery of the thoracic spinal cord in patients with achondroplasia can be performed safely if anatomical details are taken into consideration. Spondylodesis did not appear essential. Special attention should be given to the method of surgery, identification of the level of interest, and follow-up of the thoracolumbar kyphotic angle.

  4. Decompressive laminectomy for lumbar stenosis: review of 65 consecutive cases from Tema, Ghana. (United States)

    Andrews, N B; Lawson, H J; Darko, D


    There have been previous reports describing patients with lumbar stenosis (LS) in West Africa; however, to date no such report has been published from Ghana. To provide data on the pattern of lumbar stenosis and the effects of decompressive lumbar laminectomy (DLL) on the clinical course of LS in Tema. Sixty-five consecutive patients who underwent DLL for lumbar stenosis over between January 2001 and December 2004 had their medical records analyzed. The parameters of interest included demographics, pre and post surgical clinical status utilizing the modified low back pain clinical scoring system, operative procedure and complications. Sixty-five patients (36M, 29F) with a mean age of 51 years constituted the series. All had failed conservative treatment; each patient was operated on once at our institution. Eighty nine percent of the series presented with neurogenic claudication and accompanying motor and sensory deficits. Twenty-seven patients (41.5%) underwent bilateral DLL; the rest underwent unilateral DLL. The mean preoperative score for the series was 2.3; that for males 2.6, females 1.9 (p > 0.05). There was a significant difference between patients 60 years. The mean postoperative score for the series was 8.7. There was a significant difference between preoperative and postoperative scores of series. No mortality was recorded The complication rate was 15%. In Tema, decompressive lumbar laminectomy for lumbar stenosis achieves significant clinical improvement with attendant low morbidity and mortality rates in patients who have failed conservative treatment. Accompanying disc excision and or fusion are required in only a small minority of patients.

  5. Latent Presentation of Decompression Sickness After Altitude Chamber Training in an Active Duty Flier. (United States)

    Gentry, James; Rango, Juan; Zhang, Jianzhong; Biedermann, Shane


    Decompression sickness (DCS) is a potential danger and risk for both divers and aircrew alike. DCS is also a potential side effect of altitude (hypobaric) chamber training as well and can present long after training occurs. Literature review shows that altitude chamber induced DCS has approximately a 0.25% incidence. A 32-yr-old, active duty military member developed symptoms of DCS 3 h after his hypobaric chamber training. Unfortunately, he did not seek treatment for DCS until 48 h after the exposure. His initial treatment included ground level oxygen therapy for 30 min at 12 L of oxygen per minute using a nonrebreathing mask. He achieved complete symptom resolution and was returned to duty. However, 12 d after his initial Flight Medicine evaluation, the patient returned complaining of a right temporal headache, multijoint pains, and fatigue. He was treated in the hyperbaric chamber and had complete resolution of symptoms. He was returned to flying status and 5 mo later denied any return of symptoms. Hypobaric chamber familiarity training is a requirement for all military aircrew personnel to allow them assess their ability to identify symptoms of hypoxia. This training method is not only costly to maintain, but it also places aircrew and chamber technicians at risk for potential long-term side effects from failed recompression treatment of DCS. We are presenting a case of recurrent DCS symptoms 12 d after initial ground level oxygen therapy.Gentry J, Rango J, Zhang J, Biedermann S. Latent presentation of decompression sickness after altitude chamber training in an active duty flier. Aerosp Med Hum Perform. 2017; 88(4):427-430.

  6. Cognition after malignant media infarction and decompressive hemicraniectomy - a retrospective observational study

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    Neubieser Katja


    Full Text Available Abstract Background Decompressive hemicraniectomy is a life-saving procedure for patients with malignant middle cerebral artery infarctions. However, the neuropsychological sequelae in such patients have up to now received little attention. In this study we not only describe neuropsychological deficits but also the quality of life and the extent of depression and other psychiatric symptoms in patients after complete media infarction of the non-speech dominant hemisphere. Methods 20 patients from two different university hospitals (mean ± standard deviation: 52 ± 14 years of age who had undergone hemicraniectomy with duraplasty above the non-speech dominant hemisphere at least one year previously were examined using a thorough neurological and neuropsychological work-up. The quality of life and the extent of psychiatric problems were determined on the basis of self-estimation questionnaires. The patients were asked whether they would again opt for the surgical treatment when considering their own outcome. 20 healthy persons matched for age, gender and education served as a control group. Results All patients but one were neurologically handicapped, half of them severely. Age was significantly correlated with poorer values on the Rankin scale and Barthel index. All cognitive domain z values were significantly lower than in the control group. Upon re-examination, 18 of 20 patients were found to be cognitively impaired to a degree that fulfilled the formal DSM IV criteria for dementia. Conclusions Patients with non-speech dominant hemispheric infarctions and decompressive hemicraniectomy are at high risk of depression and severe cognitive impairment.

  7. Comparison of exertion required to perform standard and active compression-decompression cardiopulmonary resuscitation. (United States)

    Shultz, J J; Mianulli, M J; Gisch, T M; Coffeen, P R; Haidet, G C; Lurie, K G


    Active compression-decompression (ACD) cardiopulmonary resuscitation (CPR) utilizes a hand-held suction device with a pressure gauge that enables the operator to compress as well as actively decompress the chest. This new CPR method improves hemodynamic and ventilatory parameters when compared with standard CPR. ACD-CPR is easy to perform but may be more labor intensive. The purpose of this study was to quantify and compare the work required to perform ACD and standard CPR. Cardiopulmonary testing was performed on six basic cardiac life support- and ACD-trained St. Paul, MN fire-fighter personnel during performance of 10 min each of ACD and standard CPR on a mannequin equipped with a compression gauge. The order of CPR techniques was determined randomly with > 1 h between each study. Each CPR method was performed at 80 compressions/min (timed with a metronome), to a depth of 1.5-2 inches, and with a 50% duty cycle. Baseline cardiopulmonary measurements were similar at rest prior to performance of both CPR methods. During standard and ACD-CPR, respectively, rate-pressure product was 18.2 +/- 3.0 vs. 23.8 +/- 1.7 (x 1000, P CPR compared with standard CPR. Both methods require subanaerobic energy expenditure and can therefore be sustained for a sufficient length of time by most individuals to optimize resuscitation efforts. Due to the slightly higher work requirement, ACD-CPR may be more difficult to perform compared with standard CPR for long periods of time, particularly by individuals unaccustomed to the workload requirement of CPR, in general.

  8. Clinical and radiological outcome of craniocervical osteo-dural decompression for Chiari I-associated syringomyelia. (United States)

    Spena, Giannantonio; Bernucci, Claudio; Garbossa, Diego; Valfrè, Walter; Versari, Pietro


    The aim of this study was to analyze the long-term clinical and radiological outcomes of craniocervical decompression for patients affected by Chiari I-related syringomyelia. We performed a retrospective analysis of a group of patients affected by Chiari I-associated syringomyelia treated by craniocervical decompression (CCD). Surgical and technical aspects and preoperative factors predicting outcome were discussed. A total of 36 patients were reviewed. There were 17 men and 19 women (female/male ratio 1.11), and the mean age was 40.4 (range 18-68). The most important preoperative symptoms were related to myelopathy (pain, weakness, atrophy, spasticity, sensory loss, and dysesthesias). Most syrinxes were in the cervico-thoracic region (61.1%), and the majority of patients had tonsillar descent between the foramen magnum and C1. All patients underwent a craniectomy less than 3 cm in diameter followed by a duroplasty with dura substitute. No arachnoid manipulation was necessary. Three patients (8.1%) experienced cerebrospinal fluid leaks that resolved without complications. At a mean follow up of 40 months (range 16-72) 80.5% of patients exhibited improvement over their preoperative neurological examination while 11.1% stabilized. The syrinx shrank in 80.5% of patients. Chi-square test showed that preoperative syrinx extension and degree of tonsillar descent did not correlate with clinical and neuroradiological postoperative evolution. Treating syringomyelia associated in Chiari I malformation with CCD leads to a large percentage of patients with satisfying results and no irreversible complications.

  9. Decompressive craniectomy in massive cerebral infarction Craniectomia descompressiva no infarto cerebral extenso

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    João Paulo Mattos


    Full Text Available Twenty one patients were submitted to decompressive craniectomy for massive cerebral infarct. Ten patients (47.6% presented a good outcome at the 6 months evaluation, eight had a poor outcome (38% and three died (14.2%. There was no outcome statistical difference between surgery before and after 24 hours of ictus, dominant and non-dominant stroke groups. Patients older than 60 years and those who had a Glasgow Coma Scale (GCS8 at pre-surgical exam and decompressive craniectomy before signs of brain herniation represent the main factors related to a better outcome. Dominant hemispheric infarction does not represent exclusion criteria.Vinte e um pacientes foram submetidos a craniectomia descompressiva para o tratamento de infarto cerebral extenso. Dez pacientes (47,6% apresentaram boa evolução em avaliação após 6 meses, 8 apresentaram evolução desfavorável (38% e 3 faleceram (14,2%. Durante o seguimento, não se evidenciou diferença estatística na evolução entre pacientes operados antes e após 24 horas do ictus, nem entre lesões envolvendo o hemisfério dominante versus não dominante. Pacientes com mais de 60 anos e aqueles com Escala de Coma de Glasgow (ECG8 no exame pré-operatório e craniectomia descompressiva antes de sinais de herniação cerebral representam os principais fatores relacionados a uma melhor evolução clínica. Infarto hemisférico envolvendo o hemisfério dominante não representa um critério de exclusão.

  10. Steam explosion pretreatment of softwood: the effect of the explosive decompression on enzymatic digestibility. (United States)

    Pielhop, Thomas; Amgarten, Janick; von Rohr, Philipp Rudolf; Studer, Michael H


    Steam explosion pretreatment has been examined in many studies for enhancing the enzymatic digestibility of lignocellulosic biomass and is currently the most common pretreatment method in commercial biorefineries. The information available about the effect of the explosive decompression on the biochemical conversion is, however, very limited, and no studies prove that the latter is actually enhanced by the explosion. Hence, it is of great value to discern between the effect of the explosion on the one hand and the steaming on the other hand, to identify their particular influences on enzymatic digestibility. The effect of the explosive decompression in the steam explosion pretreatment of spruce wood chips on their enzymatic cellulose digestibility was studied systematically. The explosion had a high influence on digestibility, improving it by up to 90 % compared to a steam pretreatment without explosion. Two factors were identified to be essentially responsible for the effect of the explosion on enzymatic digestibility: pretreatment severity and pressure difference of the explosion. A higher pretreatment severity can soften up and weaken the lignocellulose structure more, so that the explosion can better break up the biomass and decrease its particle size, which enhances its digestibility. In particular, increasing the pressure difference of the explosion leads to more defibration, a smaller particle size and a better digestibility. Though differences were found in the micro- and nanostructure of exploded and non-exploded biomass, the only influence of the explosion on digestibility was found to be the macroscopic particle size reduction. Steam explosion treatments with a high severity and a high pressure difference of the explosion lead to a comparatively high cellulose digestibility of the-typically very recalcitrant-softwood biomass. This is the first study to show that explosion can enhance the enzymatic digestibility of lignocellulosic biomass. If the

  11. Angiotensin Converting Enzyme Inhibitor Has a Protective Effect on Decompression Sickness in Rats

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    Aleksandra Mazur


    Full Text Available Introduction: Commercial divers, high altitude pilots, and astronauts are exposed to some inherent risk of decompression sickness (DCS, though the mechanisms that trigger are still unclear. It has been previously showed that diving may induce increased levels of serum angiotensin converting enzyme. The renin angiotensin aldosterone system (RAAS is one of the most important regulators of blood pressure and fluid volume. The purpose of the present study was to control the influence of angiotensin II on the appearance of DCS.Methods: Sprague Dawley rats have been pre-treated with inhibitor of angiotensin II receptor type 1 (losartan; 10 mg/kg, angiotensin-converting enzyme (ACE inhibitor (enalapril; 10 mg/kg, and calcium-entry blocker (nifedipine; 20 mg/kg. The experimental groups were treated for 4 weeks before exposure to hyperbaric pressure while controls were not treated. Seventy-five rats were subjected to a simulated dive at 1000 kPa absolute pressure for 45 min before starting decompression. Clinical assessment took place over a period of 60 min after surfacing. Blood samples were collected for measurements of TBARS, interleukin 6 (IL-6, angiotensin II (ANG II and ACE.Results: The diving protocol induced 60% DCS in non-treated animals. This ratio was significantly decreased after treatment with enalapril, but not other vasoactive drugs. Enalapril did not change ANG II or ACE concentration, while losartant decreased post dive level of ACE but not ANG II. None of the treatment modified the effect of diving on TBARS and IL-6 values.Conclusion: Results suggests that the rennin angiotensin system is involved in a process of triggering DCS but this has to be further investigated. However, a vasorelaxation mediated process, which potentially could increase the load of inert gas during hyperbaric exposure, and antioxidant properties were excluded by our results.

  12. [Clinical effects of Dynesys system and transfacet decompression through Wiltse approach in the treatment of lumbar degenerative diseases]. (United States)

    Shang, K; Chen, M J; Wang, D G


    Objective: To investigate the early clinical effects of Dynesys system and transfacet decompression by Wiltse approach in the treatment of lumbar degenerative diseases. Methods: From January 2010 to December 2013, 48 patients suffering from lumbar degenerative diseases were treated with Dynesys system in addition to transfacet decompression through Wiltse approach.There were 28 males and 20 females with age of (51.8±6.8). The preoperative diagnosis included lumbar spinal stenosis(10 cases); lumber intervertebral disc herniation (38 cases). There were 23 cases in L4/5, 16 cases in L5/S1 and 9 cases in both of L4/5 and L5/S1.Posterolateral fixation with Dynesys pedicle screw through Wiltse approach.Unilateral resection of the inferior articular facet of the superior vertebra and the superior articular facet of the inferior vertebra.Decompression of the vertebral canal until the never root was decompressed satisfactorily.In the end, Dynesys was performed according to normal procedure.VAS, ODI evaluating standards were applied to evaluate the therapeutic effect.The intervertebral space and ROM of the lumbar were observed by X ray. Results: All patients underwent surgery safely without severe complications occurred.The average following up time was 33.5 (24-60) months.Compared with preoperative parameters (7.7±1.3, 70.8±13.5), the scores of VAS and ODI decreased significantly after surgery (2.3±1.5, 23.6±12.2) and at the final follow-up (2.2±1.4, 20.0±9.8) ( P 0.05). X-ray scan showed neither instability or internal fixation loosen, breakage or distortion in follow-up. Conclusion: Dynesys system in addition to transfacet decompression through Wiltse approach is a therapy option for mild lumbar degenerative disease.This method can retention the structure of lumbar posterior complex and the activity of the fixed segment, reduce the risk of low back pain together with nerve root decompressed.The early clinical results are satisfactory.

  13. A Cost-Utility Analysis of Lumbar Decompression With and Without Fusion for Degenerative Spine Disease in the Elderly. (United States)

    Devin, Clinton J; Chotai, Silky; Parker, Scott L; Tetreault, Lindsay; Fehlings, Michael G; McGirt, Matthew J


    Value-based purchasing is rapidly being implemented to rein in the unsustainably rising costs of the US healthcare system. With a growing elderly population, it is vital to understand the value of spinal surgery in this group of individuals. To compare the cost-effectiveness of lumbar decompression with and without fusion for degenerative spine disease in elderly vs nonelderly patients. A total of 221 patients undergoing elective primary surgery for degenerative lumbar pathology who were enrolled in a prospective longitudinal registry were analyzed. Patient-reported outcomes of Oswestry Disability Index, numeric rating scale for back and leg pain, and quality-of-life scores (EuroQol-5D) were recorded. Two-year back-related medical resource use, missed work, and health-state values (quality-adjusted life-years [QALYs]) were assessed. Two-year resource use was multiplied by unit costs based on Medicare national allowable payment amounts (direct cost). Patient and caregiver workday losses were multiplied by gross-of-tax wage rate (indirect cost). Patients were divided into age groups <70 and ≥70 years. Mean cumulative 2-year QALYs gained were statistically similar between younger and older patients for both decompression alone (0.67 ± 0.65 vs 0.56 ± 0.65; P = .47) and decompression with fusion (0.56 ± 0.55 vs 0.59 ± 0.55; P = .26). Mean 2-year cost per QALY gained between younger and older patients was similar for both decompression alone ($24,365 vs $31,750 per QALY; P = .11) and decompression with fusion ($64,228 vs $60,183 per QALY; P = .09). Surgical treatment provided significant improvements in pain, disability, and quality of life for elderly patients with degenerative lumbar disease. Observed costs per QALY gained for lumbar decompression with and without fusion were similar for younger and older patients, demonstrating that lumbar spine surgery in the elderly is an equally cost-effective and valuable intervention.

  14. Subcooled decompression analysis of the ROSA and the LOFT semiscale blowdown test data with the digital computer code DEPCO-MULTI

    International Nuclear Information System (INIS)

    Namatame, Ken; Kobayashi, Kensuke


    In the ROSA (Rig of Safety Assessment) program, the digital computer code DEPCO-SINGLE and DEPCO-MULTI (Subcooled Decompression Process in Loss-of-Coolant Accident - Single Pipe and - Multiple Pipe Network) were prepared to study thermo-hydraulic behavior of the primary coolant in subcooled decompression of the PWR LOCA. The analytical results with DEPCO-MULTI on the subcooled decompression phenomena are presented for ROSA-I, ROSA-II and LOFT 500, 600, 700 and 800 series experiments. The effects of space mesh length, elasticity of pressure boundary materials and simplification for computational piping system on the computed result are described. This will be the final work on the study of the subcooled decompression analysis as for the ROSA program, and the authors wish that the present code shall further be examined with the data of much advanced experiments. (auth.)

  15. Evaluation of Coflex interspinous stabilization following decompression compared with decompression and posterior lumbar interbody fusion for the treatment of lumbar degenerative disease: A minimum 5-year follow-up study. (United States)

    Yuan, Wei; Su, Qing-Jun; Liu, Tie; Yang, Jin-Cai; Kang, Nan; Guan, Li; Hai, Yong


    Few studies have compared the clinical and radiological outcomes between Coflex interspinous stabilization and posterior lumbar interbody fusion (PLIF) for degenerative lumbar disease. We compared the at least 5-year clinical and radiological outcomes of Coflex stabilization and PLIF for lumbar degenerative disease. Eighty-seven consecutive patients with lumbar degenerative disease were retrospectively reviewed. Forty-two patients underwent decompression and Coflex interspinous stabilization (Coflex group), 45 patients underwent decompression and PLIF (PLIF group). Clinical and radiological outcomes were evaluated. Coflex subjects experienced less blood loss, shorter hospital stays and shorter operative time than PLIF (all pdisease was higher in the PLIF group, but this did not achieve statistical significance (11.1% vs. 4.8%, p=0.277). Both groups provided sustainable improved clinical outcomes for lumbar degenerative disease through at least 5-year follow-up. The Coflex group had significantly better early efficacy than the PLIF group. Coflex interspinous implantation after decompression is safe and effective for lumbar degenerative disease. Copyright © 2016 Elsevier Ltd. All rights reserved.

  16. Single-stage posterior transforaminal lumbar interbody fusion, debridement, limited decompression, 3-column reconstruction, and posterior instrumentation in surgical treatment for single-segment lumbar spinal tuberculosis


    Zeng, Hao; Wang, Xiyang; Zhang, Penghui; Peng, Wei; Zhang, Yupeng; Liu, Zheng


    Objective: The aim of this study is to determine the feasibility and efficacy of surgical management of single-segment lumbar spinal tuberculosis (TB) by using single-stage posterior transforaminal lumbar interbody fusion, debridement, limited decompression, 3-column reconstruction, and posterior instrumentation.Methods: Seventeen cases of single-segment lumbar TB were treated with single-stage posterior transforaminal lumbar interbody fusion, debridement, limited decompression, 3-column reco...

  17. Early versus delayed decompression in acute subaxial cervical spinal cord injury: A prospective outcome study at a Level I trauma center from India


    Gupta, Deepak Kumar; Vaghani, Gaurang; Siddiqui, Saquib; Sawhney, Chhavi; Singh, Pankaj Kumar; Kumar, Atin; Kale, S. S.; Sharma, B. S.


    Aims: This study was done with the aim to compare the clinical outcome and patients’ quality of life between early versus delayed surgically treated patients of acute subaxial cervical spinal cord injury. The current study was based on the hypothesis that early surgical decompression and fixations in acute subaxial cervical spinal cord trauma is safe and is associated with improved outcome as compared to delayed surgical decompression. Materials and Methods: A total of 69 patients were recrui...

  18. Effect of oxygen breathing and perfluorocarbon emulsion treatment on air bubbles in adipose tissue during decompression sickness

    DEFF Research Database (Denmark)

    Randsoe, T; Hyldegaard, O


    Decompression sickness (DCS) after air diving has been treated with success by means of combined normobaric oxygen breathing and intravascular perfluorocarbon (PFC) emulsions causing increased survival rate and faster bubble clearance from the intravascular compartment. The beneficial PFC effect...... has been explained by the increased transport capacity of oxygen and inert gases in blood. However, previous reports have shown that extravascular bubbles in lipid tissue of rats suffering from DCS will initially grow during oxygen breathing at normobaric conditions. We hypothesize that the combined...... effect of normobaric oxygen breathing and intravascular PFC infusion could lead to either enhanced extravascular bubble growth on decompression due to the increased oxygen supply, or that PFC infusion could lead to faster bubble elimination due to the increased solubility and transport capacity in blood...

  19. Sigmoid volvulus in an adolescent girl: staged management with emergency colonoscopic reduction and decompression followed by elective sigmoid colectomy (United States)

    Patel, Ramnik V; Njere, Ike; Campbell, Alison; Daniel, Rejoo; Azaz, Amer; Fleet, Mahmud


    A case of acute sigmoid volvulus in a 14-year-old adolescent girl presenting with acute low large bowel obstruction with a background of chronic constipation has been presented. Abdominal radiograph and CT scan helped in diagnosis. She underwent emergency colonoscopic detorsion and decompression uneventfully. Lower gastrointestinal contrast study showed very redundant sigmoid colonic loop without any transition zone and she subsequently underwent elective sigmoid colectomy with good outcome. The sigmoid volvulus should be considered in the differential diagnosis of paediatric acute abdomen presenting with marked abdominal distention, absolute constipation and pain but without vomiting. Plain abdominal radiograph and the CT scan are helpful to confirm the diagnosis. Early colonoscopic detorsion and decompression allows direct visualisation of the vascular compromise, assessment of band width of the volvulus and can reduce complications and mortality. Associated Hirschsprung's disease should be suspected if clinical and radiological features are suggestive in which case a rectal biopsy before definitive surgery should be considered. PMID:25143313

  20. Posterior fossa reconstruction using titanium plate for the treatment of cerebellar ptosis after decompression for Chiari malformation. (United States)

    Udani, Vikram; Holly, Langston T; Chow, Daniel; Batzdorf, Ulrich


    We describe our use of a perforated titanium plate to perform a partial posterior fossa cranioplasty in the treatment of cerebellar ptosis and dural ectasia after posterior fossa decompression (PFD). Twelve patients who had undergone PFD underwent posterior fossa reconstruction using a titanium plate. Symptoms were related to either descent of the cerebellum into the decompression or to dural ectasia into the craniectomy defect. Twelve patients who had undergone large suboccipital craniectomies and who presented with persistent headaches and some with neurological symptoms related to syringomyelia, underwent reoperation with placement of a small titanium plate. Ten of 12 patients showed symptomatic improvement after reoperation. Placement of a titanium plate appears to be an effective method of treatment of cerebellar ptosis and dural ectasia after PFD for Chiari malformation. Copyright © 2014 Elsevier Inc. All rights reserved.

  1. Decompression Retinopathy after ExPRESS Shunt Implantation for Steroid-Induced Ocular Hypertension: A Case Report

    Directory of Open Access Journals (Sweden)

    Khawla Abu Samra


    Full Text Available Purpose. To present a unique case of decompression retinopathy after the implantation of ExPRESS drainage device. Method. A 25-year-old female patient underwent implantation of ExPRESS drainage device in the left eye for the management of steroid-induced ocular hypertension. Results. On the postoperative day one, best-corrected visual acuity in the left eye was 20/50. Fundus examination revealed diffuse intraretinal hemorrhages, some white-centered, throughout the retina. There was also marked tortuosity to the retinal vasculature and no evidence of choroidal effusion. Intravenous fluorescein angiography and indocyanine green did not contribute to the aetiopathogenesis. Conclusion. Decompression retinopathy can occur following the implantation of ExPRESS drainage device. It is very important to be aware of this complication in patients with relatively high intraocular pressure who is planned for filtration surgery, including the ExPRESS implant.

  2. Five-year durability of stand-alone interspinous process decompression for lumbar spinal stenosis

    Directory of Open Access Journals (Sweden)

    Nunley PD


    Full Text Available Pierce D Nunley,1 Vikas V Patel,2 Douglas G Orndorff,3 William F Lavelle,4 Jon E Block,5 Fred H Geisler6 1Spine Institute of Louisiana, Shreveport, LA, 2The Spine Center, University of Colorado Hospital, Denver, CO, 3Spine Colorado, Mercy Regional Hospital, Durango, CO, 4Upstate Bone and Joint Center, East Syracuse, NY, 5Independent Consultant, San Francisco, CA, 6Independent Consultant, Chicago, IL, USA Background: Lumbar spinal stenosis is the most common indication for spine surgery in older adults. Interspinous process decompression (IPD using a stand-alone spacer that functions as an extension blocker offers a minimally invasive treatment option for intermittent neurogenic claudication associated with spinal stenosis.Methods: This study evaluated the 5-year clinical outcomes for IPD (Superion® from a randomized controlled US Food and Drug Administration (FDA noninferiority trial. Outcomes included Zurich Claudication Questionnaire (ZCQ symptom severity (ss, physical function (pf, and patient satisfaction (ps subdomains, leg and back pain visual analog scale (VAS, and Oswestry Disability Index (ODI.Results: At 5 years, 84% of patients (74 of 88 demonstrated clinical success on at least two of three ZCQ domains. Individual ZCQ domain success rates were 75% (66 of 88, 81% (71 of 88, and 90% (79 of 88 for ZCQss, ZCQpf, and ZCQps, respectively. Leg and back pain success rates were 80% (68 of 85 and 65% (55 of 85, respectively, and the success rate for ODI was 65% (57 of 88. Percentage improvements over baseline were 42%, 39%, 75%, 66%, and 58% for ZCQss, ZCQpf, leg and back pain VAS, and ODI, respectively (all P<0.001. Within-group effect sizes were classified as very large for four of five clinical outcomes (ie, >1.0; all P<0.0001. Seventy-five percent of IPD patients were free from reoperation, revision, or supplemental fixation at their index level at 5 years.Conclusion: After 5 years of follow-up, IPD with a stand-alone spacer provides

  3. The responsiveness of sensibility and strength tests in patients undergoing carpal tunnel decompression

    Directory of Open Access Journals (Sweden)

    Miller Leanne


    Full Text Available Abstract Background Several clinical measures of sensory and motor function are used alongside patient-rated questionnaires to assess outcomes of carpal tunnel decompression. However there is a lack of evidence regarding which clinical tests are most responsive to clinically important change over time. Methods In a prospective cohort study 63 patients undergoing carpal tunnel decompression were assessed using standardised clinician-derived and patient reported outcomes before surgery, at 4 and 8 months follow up. Clinical sensory assessments included: touch threshold with monofilaments (WEST, shape-texture identification (STI™ test, static two-point discrimination (Mackinnon-Dellon Disk-Criminator and the locognosia test. Motor assessments included: grip and tripod pinch strength using a digital grip analyser (MIE, manual muscle testing of abductor pollicis brevis and opponens pollicis using the Rotterdam Intrinsic Handheld Myometer (RIHM. The Boston Carpal Tunnel Questionnaire (BCTQ was used as a patient rated outcome measure. Results Relative responsiveness at 4 months was highest for the BCTQ symptom severity scale with moderate to large effects sizes (ES = -1.43 followed by the BCTQ function scale (ES = -0.71. The WEST and STI™ were the most responsive sensory tests at 4 months showing moderate effect sizes (WEST ES = 0.55, STI ES = 0.52. Grip and pinch strength had a relatively higher responsiveness compared to thenar muscle strength but effect sizes for all motor tests were very small (ES ≤0.10 or negative indicating a decline compared to baseline in some patients. Conclusions For clinical assessment of sensibility touch threshold assessed by monofilaments (WEST and tactile gnosis measured with the STI™ test are the most responsive tests and are recommended for future studies. The use of handheld myometry (RIHM for manual muscle testing, despite more specifically targeting thenar muscles, was less responsive than grip or tripod

  4. Does minimal access tubular assisted spine surgery increase or decrease complications in spinal decompression or fusion? (United States)

    Fourney, Daryl R; Dettori, Joseph R; Norvell, Daniel C; Dekutoski, Mark B


    Systematic review. The purpose of this review was to attempt to answer the following 2 clinical questions: (1) Does minimal access tubular assisted spine surgery (MAS) decrease the rate of complications in posterior thoracolumbar decompression and/or fusion surgery compared with traditional open techniques? (2) What strategies to reduce the risk of complications in MAS have been shown to be effective? The objective of minimal access spine surgery is to reduce damage to surrounding tissues while accomplishing the same goals as conventional surgery. Patient demand and marketing for MAS is driven by the perception of better outcomes, although the purported advantages remain unproven. Whether the risk of complications is affected by minimal access techniques is unknown. A systematic review of the English language literature was undertaken for articles published between 1990 and July 2009. Electronic databases and reference lists of key articles were searched to identify published studies that compared the rate of complications after MAS to a control group that underwent open surgery. Single-arm studies were excluded. Two independent reviewers assessed the strength of literature using GRADE criteria assessing quality, quantity, and consistency of results. Disagreements were resolved by consensus. From the 361 articles identified, 13 met a priori criteria and were included for review. All of the studies evaluated only lumbar spine surgery. The single large randomized study showed less favorable results for MAS discectomy, but no significant difference in complication rates. The quality of the other studies, particularly for fusion surgery, was low. Overall, the rates of reoperation, dural tear, cerebrospinal fluid leak, nerve injury, and infection occurred in similar proportions between MAS and open surgery. Blood loss was reduced in MAS fusion; however, the quality of those studies was very low. Operation time and hospital length of stay was variable across studies

  5. Pharmacological versus microvascular decompression approaches for the treatment of trigeminal neuralgia: clinical outcomes and direct costs

    Directory of Open Access Journals (Sweden)

    Almeida A


    Full Text Available Laurinda Lemos1,2, Carlos Alegria3, Joana Oliveira3, Ana Machado2, Pedro Oliveira4, Armando Almeida11Life and Health Sciences Research Institute (ICVS, School of Health Sciences, Campus de Gualtar, University of Minho, Braga, Portugal; 2Hospital Center of Alto Ave, Unit of Fafe, Fafe, Portugal; 3Department of Neurosurgery, Hospital São Marcos; 4Products and Systems Engineering, Campus de Azurém, University of Minho, Guimarães, PortugalAbstract: In idiopathic trigeminal neuralgia (TN the neuroimaging evaluation is usually normal, but in some cases a vascular compression of trigeminal nerve root is present. Although the latter condition may be referred to surgery, drug therapy is usually the first approach to control pain. This study compared the clinical outcome and direct costs of (1 a traditional treatment (carbamazepine [CBZ] in monotherapy [CBZ protocol], (2 the association of gabapentin (GBP and analgesic block of trigger-points with ropivacaine (ROP (GBP+ROP protocol, and (3 a common TN surgery, microvascular decompression of the trigeminal nerve (MVD protocol. Sixty-two TN patients were randomly treated during 4 weeks (CBZ [n = 23] and GBP+ROP [n = 17] protocols from cases of idiopathic TN, or selected for MVD surgery (n = 22 due to intractable pain. Direct medical cost estimates were determined by the price of drugs in 2008 and the hospital costs. Pain was evaluated using the Numerical Rating Scale (NRS and number of pain crises; the Hospital Anxiety and Depression Scale, Sickness Impact Profile, and satisfaction with treatment and hospital team were evaluated. Assessments were performed at day 0 and 6 months after the beginning of treatment. All protocols showed a clinical improvement of pain control at month 6. The GBP+ROP protocol was the least expensive treatment, whereas surgery was the most expensive. With time, however, GBP+ROP tended to be the most and MVD the least expensive. No sequelae resulted in any patient after drug

  6. A new improved method for assessing brain deformation after decompressive craniectomy.

    Directory of Open Access Journals (Sweden)

    Tim L Fletcher

    Full Text Available Decompressive craniectomy (DC is a surgical intervention used following traumatic brain injury to prevent or alleviate raised intracranial pressure. However the clinical effectiveness of the intervention remains in doubt. The location of the craniectomy (unilateral or bifrontal might be expected to change the brain deformation associated with the operation and hence the clinical outcome. As existing methods for assessing brain deformation have several limitations, we sought to develop and validate a new improved method.Computed tomography (CT scans were taken from 27 patients who underwent DC (17 bifrontal patients and 10 unilateral patients. Pre-operative and post-operative images were processed and registered to determine the change in brain position associated with the operation. The maximum deformation in the herniated brain, the change in volume and estimates of the craniectomy area were determined from the images. Statistical comparison was made using the Pearson's correlation coefficient r and a Welch's two-tailed T-test, with statistical significance reported at the 5% level.There was a reasonable correlation between the volume increase and the maximum brain displacement (r = 0.64, a low correlation between the volume increase and the craniectomy area (r = 0.30 and no correlation between the maximum displacement and the craniectomy area (r = -0.01. The maximum deformation was significantly lower (P  = 0.023 in the bifrontal patients (mean = 22.5 mm compared with the unilateral patients (mean = 29.8 mm. Herniation volume was significantly lower (P = 0.023 in bifrontal (mean = 50.0 ml than unilateral patients (mean = 107.3 ml. Craniectomy area was not significantly different for the two craniectomy locations (P = 0.29.A method has been developed to quantify changes in brain deformation due to decompressive craniectomy from CT images and allow comparison between different craniectomy locations

  7. Field validation of Tasmania's aquaculture industry bounce-diving schedules using Doppler analysis of decompression stress. (United States)

    Smart, David R; Van den Broek, Cory; Nishi, Ron; Cooper, P David; Eastman, David


    Tasmania's aquaculture industry produces over 40,000 tonnes of fish annually, valued at over AUD500M. Aquaculture divers perform repetitive, short-duration bounce dives in fish pens to depths up to 21 metres' sea water (msw). Past high levels of decompression illness (DCI) may have resulted from these 'yo-yo' dives. This study aimed to assess working divers, using Doppler ultrasonic bubble detection, to determine if yo-yo diving was a risk factor for DCI, determine dive profiles with acceptable risk and investigate productivity improvement. Field data were collected from working divers during bounce diving at marine farms near Hobart, Australia. Ascent rates were less than 18 m·min⁻¹, with routine safety stops (3 min at 3 msw) during the final ascent. The Kisman-Masurel method was used to grade bubbling post dive as a means of assessing decompression stress. In accordance with Defence Research and Development Canada Toronto practice, dives were rejected as excessive risk if more than 50% of scores were over Grade 2. From 2002 to 2008, Doppler data were collected from 150 bounce-dive series (55 divers, 1,110 bounces). Three series of bounce profiles, characterized by in-water times, were validated: 13-15 msw, 10 bounces inside 75 min; 16-18 msw, six bounces inside 50 min; and 19-21 msw, four bounces inside 35 min. All had median bubble grades of 0. Further evaluation validated two successive series of bounces. Bubble grades were consistent with low-stress dive profiles. Bubble grades did not correlate with the number of bounces, but did correlate with ascent rate and in-water time. These data suggest bounce diving was not a major factor causing DCI in Tasmanian aquaculture divers. Analysis of field data has improved industry productivity by increasing the permissible number of bounces, compared to earlier empirically-derived tables, without compromising safety. The recommended Tasmanian Bounce Diving Tables provide guidance for bounce diving to a depth of 21 msw

  8. Clinical study of bilateral decompression via vertebral lamina fenestration for lumbar interbody fusion in the treatment of lower lumbar instability




    The aim of this study was to observe the clinical effects of bilateral decompression via vertebral lamina fenestration for lumbar interbody fusion in the treatment of lower lumbar instability. The 48 patients comprised 27 males and 21 females, aged 47?72 years. Three cases had first and second degree lumbar spondylolisthesis and all received bilateral vertebral lamina fenestration for posterior lumbar interbody fusion (PLIF) using a threaded fusion cage (TFC), which maintains the three-column...

  9. Application of small intestine decompression combined with oral feeding in middle and late period of malignant small bowel obstruction. (United States)

    Li, Dechun; Du, Hongtao; Shao, Guoqing; Guo, Yongtuan; Lu, Wan; Li, Ruihong


    The application value of small intestine decompression combined with oral feeding in the middle and late period of malignant small bowel obstruction was examined. A total of 22 patients with advanced malignant small bowel obstruction were included in the present study. An ileus tube was inserted via the nose under fluoroscopy into the obstructed small intestine of each patient. At the same time, the insertion depth the of the catheter was adjusted. When the catheter was blocked, small bowel selective angiography was performed to determine the location and cause of the obstruction and the extent of the obstruction, and to determine the length of the small intestine in the site of obstruction, and to select the variety and tolerance of enteral nutrition. We observed the decompression tube flow and ease of intestinal obstruction. In total, 20 patients were treated with oral enteral nutrition after abdominal distension, and 22 cases were treated by the nose to observe the drainage and the relief of intestinal obstruction. The distal end of the catheter was placed in a predetermined position. The symptoms of intestinal obstruction were relieved 1-4 days after decompression. The 22 patients with selective angiography of the small intestine showed positive X-ray signs: 18 patients with oral enteral nutrition therapy had improved the nutritional situation 2 weeks later. In 12 cases, where there was anal defecation exhaust, 2 had transient removal of intestinal obstruction catheter. In conclusion, this comprehensive treatment based on small intestine decompression combined with enteral nutrition is expected to become a new therapeutic approach and method for the treatment of patients with advanced tumor small bowel obstruction.

  10. Craniectomy-associated Progressive Extra-Axial Collections with Treated Hydrocephalus (CAPECTH): redefining a common complication of decompressive craniectomy. (United States)

    Nalbach, Stephen V; Ropper, Alexander E; Dunn, Ian F; Gormley, William B


    Extra-axial fluid collections following decompressive craniectomy have been observed in a variety of patient populations. These collections have traditionally been thought to represent extra-axial signs of hydrocephalus, but they often occur even in settings where hydrocephalus has been optimally treated. This study aims to elucidate the phenomenon of extra-axial fluid collections after decompressive craniectomy in patients with treated hydrocephalus, in order to improve identification, classification, prevention and treatment. We retrospectively reviewed all patients at a single institution undergoing decompressive craniectomy for refractory intracranial pressure elevations from June 2007 through December 2009. We identified 39 patients by reviewing clinical reports and imaging. Any patient who died on or prior to the third post-operative day (POD) was excluded. The analysis focused on patients with extra-axial collections and treated hydrocephalus. Twenty-one of 34 (62%) patients developed extra-axial collections and 18 of these developed collections despite ventricular drainage. Subgroup analysis revealed that seven of seven patients (100%) with subarachnoid hemorrhage, and 11 of 14 (79%) with traumatic brain injury developed collections. Extra-axial collections may develop after decompressive craniectomy despite aggressive treatment of communicating hydrocephalus. In these patients, the term "external hydrocephalus" does not appropriately capture the relevant pathophysiology. Instead, we define a new phenomenon, "Craniectomy-associated Progressive Extra-Axial Collections with Treated Hydrocephalus" (CAPECTH), as progressive collections despite aggressive cerebral spinal fluid (CSF) drainage. Our data indicate that early cranioplasty can help prevent the formation and worsening of this condition, presumably by returning normal CSF dynamics. Copyright © 2012 Elsevier Ltd. All rights reserved.

  11. Incidence of Decompression Illness and Other Diving Related Medical Problems Amongst Royal Navy Divers 1995-1999 (United States)


    conditions hypobares ou hyperbares ] To order the complete compilation report, use: ADA395680 The component part is provided here to allow users access to...following report: TITLE: Operational Medical Issues in Hypo-and Hyperbaric Conditions [les Questions medicales a caractere oprationel liees aux...Navy diving accidents, and with the assistance of the British Hyperbaric Association (BHA) all civilian cases of decompression illness treated by member

  12. Favourable outcome of posterior decompression and stabilization in lordosis for cervical spondylotic myelopathy: the spinal cord "back shift" concept. (United States)

    Denaro, Vincenzo; Longo, Umile Giuseppe; Berton, Alessandra; Salvatore, Giuseppe; Denaro, Luca


    Surgical management of patients with multilevel CSM aims to decompress the spinal cord and restore the normal sagittal alignment. The literature lacks of high level evidences about the best surgical approach. Posterior decompression and stabilization in lordosis allows spinal cord back shift, leading to indirect decompression of the anterior spinal cord. The purpose of this study was to investigate the efficacy of posterior decompression and stabilization in lordosis for multilevel CSM. 36 out of 40 patients were clinically assessed at a mean follow-up of 5, 7 years. Outcome measures included EMS, mJOA Score, NDI and SF-12. Patients were asked whether surgery met their expectations and if they would undergo the same surgery again. Bone graft fusion, instrumental failure and cervical curvature were evaluated. Spinal cord back shift was measured and correlation with EMS and mJOA score recovery rate was analyzed. All scores showed a significative improvement (p 0.05). Ninety percent of patients would undergo the same surgery again. There was no deterioration of the cervical alignment, posterior grafted bones had completely fused and there were no instrument failures. The mean spinal cord back shift was 3.9 mm (range 2.5-4.5 mm). EMS and mJOA recovery rates were significantly correlated with the postoperative posterior cord migration (P lordosis is a valuable procedure for patients affected by multilevel CSM, leading to significant clinical improvement thanks to the spinal cord back shift. Postoperative lordotic alignment of the cervical spine is a key factor for successful treatment.

  13. Impact of sagittal spinopelvic alignment on clinical outcomes after decompression surgery for lumbar spinal canal stenosis without coronal imbalance. (United States)

    Hikata, Tomohiro; Watanabe, Kota; Fujita, Nobuyuki; Iwanami, Akio; Hosogane, Naobumi; Ishii, Ken; Nakamura, Masaya; Toyama, Yoshiaki; Matsumoto, Morio


    The object of this study was to investigate correlations between sagittal spinopelvic alignment and improvements in clinical and quality-of-life (QOL) outcomes after lumbar decompression surgery for lumbar spinal canal stenosis (LCS) without coronal imbalance. The authors retrospectively reviewed data from consecutive patients treated for LCS with decompression surgery in the period from 2009 through 2011. They examined correlations between preoperative or postoperative sagittal vertical axis (SVA) and radiological parameters, clinical outcomes, and health-related (HR)QOL scores in patients divided according to SVA. Clinical outcomes were assessed according to Japanese Orthopaedic Association (JOA) and visual analog scale (VAS) scores. Health-related QOL was evaluated using the Roland-Morris Disability Questionnaire (RMDQ) and the JOA Back Pain Evaluation Questionnaire (JOABPEQ). One hundred nine patients were eligible for inclusion in the study. Compared to patients with normal sagittal alignment prior to surgery (Group A: SVA imbalance (Group B: SVA ≥ 50 mm) had significantly smaller lumbar lordosis and thoracic kyphosis angles and larger pelvic tilt. In Group B, there was a significant decrease in postoperative SVA compared with the preoperative SVA (76.3 ± 29.7 mm vs. 54.3 ± 39.8 mm, p = 0.004). The patients in Group B with severe preoperative sagittal imbalance (SVA > 80 mm) had residual sagittal imbalance after surgery (82.8 ± 41.6 mm). There were no significant differences in clinical and HRQOL outcomes between Groups A and B. Compared to patients with normal postoperative SVA (Group C: SVA imbalance. Decompression surgery improved the SVA value in patients with preoperative sagittal imbalance; however, the patients with severe preoperative sagittal imbalance (SVA > 80 mm) had residual imbalance after decompression surgery. Both clinical and HRQOL outcomes were negatively affected by postoperative residual sagittal imbalance.

  14. The effects of massage therapy after decompression and fusion surgery of the lumbar spine: a case study. (United States)

    Keller, Glenda


    Spinal fusion and decompression surgery of the lumbar spine are common procedures for problems such as disc herniations. Various studies for postoperative interventions have been conducted; however, no massage therapy studies have been completed. The objective of this study is to determine if massage therapy can beneficially treat pain and dysfunction associated with lumbar spinal decompression and fusion surgery. Client is a 47-year-old female who underwent spinal decompression and fusion surgery of L4/L5 due to chronic disc herniation symptoms. The research design was a case study in a private clinic involving the applications of seven, 30-minute treatments conducted over eight weeks. Common Swedish massage and myofascial techniques were applied to the back, shoulders, posterior hips, and posterior legs. Outcomes were assessed using the following measures: VAS pain scale, Hamstring Length Test, Oswestry Disability Index, and the Roland-Morris Disability Questionnaire. Hamstring length improved (in degrees of extension) from pretreatment measurements in the right leg of 40° and left leg 65° to post-treatment measurement at the final visit, when the results were right 50° and left 70°. The Oswestry Disability Index improved 14%, from 50% to 36% disability. Roland-Morris Disability decreased 1 point, from 3/24 to 2/24. The VAS pain score decreased by 2 points after most treatments, and for three of the seven treatments, client had a post-treatment score of 0/10. Massage for pain had short-term effects. Massage therapy seemed to lengthen the hamstrings bilaterally. Massage therapy does appear to have positive effects in the reduction of disability. This study is beneficial for understanding the relationship between massage therapy and clients who have undergone spinal decompression and fusion. Further research is warranted.

  15. Comparison of Porcine and Bovine Collagen Dural Substitutes in Posterior Fossa Decompression for Chiari I Malformation in Adults. (United States)

    Lee, Christine K; Mokhtari, Tara; Connolly, Ian D; Li, Gordon; Shuer, Lawrence M; Chang, Steven D; Steinberg, Gary K; Hayden Gephart, Melanie


    Posterior fossa decompression surgeries for Chiari malformations are susceptible to postoperative complications such as pseudomeningocele, external cerebrospinal fluid (CSF) leak, and meningitis. Various dural substitutes have been used to improve surgical outcomes. This study examined whether the collagen matrix dural substitute type correlated with the incidence of postoperative complications after posterior fossa decompression in adult patients with Chiari I malformations. A retrospective cohort study was conducted of 81 adult patients who underwent an elective decompressive surgery for treatment of symptomatic Chiari I malformations, with duraplasty involving a dural substitute derived from either bovine or porcine collagen matrix. Demographics and treatment characteristics were correlated with surgical outcomes. A total of 81 patients were included in the study. Compared with bovine dural substitute, porcine dural substitute was associated with a significantly higher risk of pseudomeningocele occurrence (odds ratio, 5.78; 95% confidence interval, 1.65-27.15; P = 0.01) and a higher overall complication rate (odds ratio, 3.70; 95% confidence interval, 1.23-12.71; P = 0.03) by univariate analysis. There was no significant difference in the rate of meningitis, repeat operations, or overall complication rate between the 2 dural substitutes. In addition, estimated blood loss was a significant risk factor for meningitis (P = 0.03). Multivariate analyses again showed that porcine dural substitute was associated with pseudomeningocele occurrence, although the association with higher overall complication rate did not reach significance. Dural substitutes generated from porcine collagen, compared with those from bovine collagen, were associated with a higher likelihood of pseudomeningocele development in adult patients undergoing Chiari I malformation decompression and duraplasty. Copyright © 2017 Elsevier Inc. All rights reserved.

  16. Changes in peripapillary blood vessel density in Graves' orbitopathy after orbital decompression surgery as measured by optical coherence tomography angiography. (United States)

    Lewis, Kyle T; Bullock, John R; Drumright, Ryan T; Olsen, Matthew J; Penman, Alan D


    The purpose is to evaluate the utility of optical coherence tomography (OCT) angiography in the evaluation of Graves' orbitopathy (GO) and response to orbital decompression in patients with and without dysthyroid optic neuropathy (DON). This was a single-center, prospective case series in a cohort of 12 patients (24 orbits) with GO and ±DON, (6 orbits) who underwent bilateral orbital decompression. All patients underwent pre- and postoperative OCT angiography of the peripapillary area. Vessel density indices were calculated in a 4.5 mm × 4.5 mm ellipsoid centered on the optic disk using split-spectrum amplitude decorrelation angiography algorithm, producing the vessel density measurements. Mean change in vessel density indices was compared between pre- and postoperative sessions and between patients with and without DON. Patient 1, a 34-year-old male with GO and unilateral DON OD, showed a significant reduction in blood vessel density indices oculus dexter (OD) (DON eye) after decompression while a more modest reduction was found oculus sinister (OS) with the greatest change noted intrapapillary. Patient 2, a 50-year-old male with DON OU, showed worsening neuropathy following decompression OD that was confirmed by angiographic density indices. Patient 3, a 55-year-female with DON, showed a reduction in blood vessel density OD and increased density OS. Patients without DON showed overall less impressive changes in indices as compared to those with DON. Using OCT angiography, response to surgical treatment in GO orbits, more so in orbits with DON, can be demonstrated and quantified using vessel density indices with reproducibility.

  17. Posterior Decompression, Lumber Interbody Fusion and Internal Fixation in the Treatment of Upper Lumbar Intervertebral Disc Herniation

    Directory of Open Access Journals (Sweden)

    DONG Zhan


    Full Text Available Objective: To assess the clinical outcomes of posterior decompression, interbody fusion and internal fixationfor the treatment of the upper lumbar intervertebral disc herniation. Methods: Twelve patients with the upper lumbar intervertebral disc herniation were treated by posterior decompression, interbosy fusion and internal fixation. The time of the operation, the amount of bleeding and the clinical efficacy were evaluated. Results: The time of operation was (143±36 min and the amount of bleeding during operation was (331.5±47.9 mL. There was no spinal cord and injuries, nerve injury, epidural damage and leakage of cerebrospinal fluid. All patients were followed up for 10~19 months with the average being 12.6 months. The functional scoring of Japanese Orthopedic Association (JOA before the operation was (11.4±3.3 scores and final score after follow-up was (22.9±3.1 scores and there were statistical difference (P<0.01. Lumber interbody fusion of all patients completed successfully and the good rate after the operation was 91.7%. Conclusion: Posterior decompression, interbody fusion and internal fixation for the treatment of the upper lumbar intervertebral disc herniation was characterized by full exposure, safety and significant efficacy.

  18. A review of the influence of physical condition parameters on a typical aerospace stress effect: Decompression sickness (United States)

    West, V. R.; Parker, J. F., Jr.


    The study examines data on episodes of decompression sickness, particularly from recent Navy work in which the event occurred under multiple stress conditions, to determine the extent to which decompression sickness might be predicted on the basis of personal characteristics such as age, weight, and physical condition. Such information should ultimately be useful for establishing medical selection criteria to screen individuals prior to participation inactivities involving extensive changes in ambient pressure, including those encountered in space operations. The main conclusions were as follows. There is a definite and positive relationship between increasing age and weight and the likelihood of decompression sickness. However, for predictive purposes, the relationship is low. To reduce the risk of bends, particularly for older individuals, strenuous exercise should be avoided immediately after ambient pressure changes. Temperatures should be kept at the low end of the comfort zone. For space activities, pressure changes of over 6-7 psi should be avoided. Prospective participants in future missions such as the Space Shuttle should not be excluded on the basis of age, certainly to age 60, if their general condition is reasonably good and they are not grossly obese. (Modified author abstract)

  19. How low can they go when going with the flow? Tolerance of egg and larval fishes to rapid decompression

    Energy Technology Data Exchange (ETDEWEB)

    Boys, Craig A.; Robinson, Wayne; Miller, Brett; Pflugrath, Brett; Baumgartner, Lee J.; Navarro, Anna; Brown, Richard; Deng, Zhiqun


    Egg and larval fish that drift downstream are likely to encounter river infrastructure and consequently rapid decompression, which may result in significant injury. In juvenile fish, pressure-related injury (or barotrauma) occurs when pressures fall sufficiently below the pressure at which the fish has acclimated. Because eggs and larvae are less-developed and more fragile than juveniles, there is a presumption that they may be at least as, if not more, susceptible to barotrauma injury, but studies to date report inconsistent results and none have considered the relationship between pressure change and barotrauma over a sufficiently broad range of pressure changes to enable detrimental levels to be properly determined. To address this, we exposed eggs and larvae of three physoclistic species to rapid decompression in a barometric chamber over a broad range of discrete pressure changes. Eggs, but not larvae, were unaffected by all levels of decompression tested. At exposure pressures below ~40 kPa, or ~40% of atmospheric pressure, swim bladder deflation occurred in all species and internal haemorrhage was observed in one species. None of these injuries killed the fish within 24 hours, but subsequent mortality cannot be excluded. Consequently, if larval drift is expected, it seems prudent to maintain exposure pressures at river infrastructure at 40% or more of the pressure to which a drifting larvae has acclimated.

  20. Keyhole craniotomy through retrosigmoid approach followed by microvascular decompression for primary trigeminal neuralgia:a report of 23 cases

    Directory of Open Access Journals (Sweden)

    Gang-ge CHENG


    Full Text Available Objective To explore the surgical technique,effects,and complications of keyhole craniotomy through retrosigmoid approach followed by microvascular decompression for primary trigeminal neuralgia.Methods The craniotomy with a keyhole incision above postauricular hairline followed by microvascular decompression was performed in 23 patients with primary trigeminal neuralgia.Dissection of intracranial part of trigeminal nerve under microscope was done to search for the offending vessels,which were thereby freed and between which and the root entry zone(REZ of trigeminal nerve the Teflon grafts were placed.Effects and complications were observed in follow-up,ranging from 1 month to 2 years.Results Out of 23 patients who were all found compression in REZ of trigeminal nerves by the offending vessels in operation,disappearance of symptoms post-surgery was found in 22 cases,face numbness on the surgical side in 3 cases and no effects in 1 case.Recurrence of pain was not observed in patients who had initially benefited from the surgery at the follow-up.Conclusion The keyhole craniotomy through retrosigmoid approach followed by microvascular decompression is safe and effective for primary trigeminal neuralgia,in which accurate technique during operation plays a vital role in the decrease of complications and the outcome post-surgery.

  1. How low can they go when going with the flow? Tolerance of egg and larval fishes to rapid decompression

    Directory of Open Access Journals (Sweden)

    Craig A. Boys


    Full Text Available Egg and larval fish that drift downstream are likely to encounter river infrastructure and consequently rapid decompression, which may result in significant injury. Pressure-related injury (or barotrauma has been shown in juvenile fishes when pressure falls sufficiently below that at which the fish has acclimated. There is a presumption that eggs and larvae may be at least as, if not more, susceptible to barotrauma injury because they are far less-developed and more fragile than juveniles, but studies to date report inconsistent results and none have considered the relationship between pressure change and barotrauma over a sufficiently broad range of pressure changes to enable tolerances to be properly determined. To address this, we exposed eggs and larvae of three physoclistic species to rapid decompression in a barometric chamber over a broad range of discrete pressure changes. Eggs, but not larvae, were unaffected by all levels of decompression tested. At exposure pressures below ∼40 kPa, or ∼40% of surface pressure, swim bladder deflation occurred in all species and internal haemorrhage was observed in one species. None of these injuries killed the fish within 24 h, but subsequent mortality cannot be excluded. Consequently, if larval drift is expected where river infrastructure is present, adopting design or operational features which maintain exposure pressures at 40% or more of the pressure to which drifting larvae are acclimated may afford greater protection for resident fishes.

  2. Surgical decompression for space-occupying cerebral infarction: outcomes at 3 years in the randomized HAMLET trial. (United States)

    Geurts, Marjolein; van der Worp, H Bart; Kappelle, L Jaap; Amelink, G Johan; Algra, Ale; Hofmeijer, Jeannette


    We assessed whether the effects of surgical decompression for space-occupying hemispheric infarction, observed at 1 year, are sustained at 3 years. Patients with space-occupying hemispheric infarction, who were enrolled in the Hemicraniectomy After Middle cerebral artery infarction with Life-threatening Edema Trial within 4 days after stroke onset, were followed up at 3 years. Outcome measures included functional outcome (modified Rankin Scale), death, quality of life, and place of residence. Poor functional outcome was defined as modified Rankin Scale >3. Of 64 included patients, 32 were randomized to decompressive surgery and 32 to best medical treatment. Just as at 1 year, surgery had no effect on the risk of poor functional outcome at 3 years (absolute risk reduction, 1%; 95% confidence interval, -21 to 22), but it reduced case fatality (absolute risk reduction, 37%; 95% confidence interval, 14-60). Sixteen surgically treated patients and 8 controls lived at home (absolute risk reduction, 27%; 95% confidence interval, 4-50). Quality of life improved between 1 and 3 years in patients treated with surgery. In patients with space-occupying hemispheric infarction, the effects of decompressive surgery on case fatality and functional outcome observed at 1 year are sustained at 3 years. Unique identifier: ISRCTN94237756.

  3. Online remote control systems for static and dynamic compression and decompression using diamond anvil cells

    International Nuclear Information System (INIS)

    Sinogeikin, Stanislav V.; Smith, Jesse S.; Rod, Eric; Lin, Chuanlong; Kenney-Benson, Curtis; Shen, Guoyin


    The ability to remotely control pressure in diamond anvil cells (DACs) in accurate and consistent manner at room temperature, as well as at cryogenic and elevated temperatures, is crucial for effective and reliable operation of a high-pressure synchrotron facility such as High Pressure Collaborative Access Team (HPCAT). Over the last several years, a considerable effort has been made to develop instrumentation for remote and automated pressure control in DACs during synchrotron experiments. We have designed and implemented an array of modular pneumatic (double-diaphragm), mechanical (gearboxes), and piezoelectric devices and their combinations for controlling pressure and compression/decompression rate at various temperature conditions from 4 K in cryostats to several thousand Kelvin in laser-heated DACs. Because HPCAT is a user facility and diamond cells for user experiments are typically provided by users, our development effort has been focused on creating different loading mechanisms and frames for a variety of existing and commonly used diamond cells rather than designing specialized or dedicated diamond cells with various drives. In this paper, we review the available instrumentation for remote static and dynamic pressure control in DACs and show some examples of their applications to high pressure research

  4. Decompression sickness rates for chamber personnel: case series from one facility. (United States)

    Brandt, Megan S; Morrison, Thomas O; Butler, William P


    During 2004, a case series of decompression sickness (DCS) meeting the definition of epidemic DCS was observed in the Shaw AFB Physiological Training Program. There were 10 cases of chamber-induced altitude DCS observed. Internal and external investigations focused on time, place, person, and environment. No temporal trend was observed. Chamber, masks, regulators, crew positions, and oxygen sources revealed no defects. Among the cases, mean age was 27 yr. Peak altitude in four cases was 35,000 ft and in the other six cases was 25,000 ft. Six had joint pain, one skin symptoms, and three neurological findings. Four were treated with 100% ground-level oxygen and six with hyperbaric oxygen. Four were students and six were inside observers (IO). Four were women and six men. In the IO, where four of the six were women, no gender effect was seen. Examining the IO monthly exposure load (exposures per month) against DCS suggested a dose-response relationship. This relationship held true when 4 yr of Shaw AFB IO data was studied. Indeed, Poisson regression analysis demonstrated a statistically significant 2.1-fold rise in DCS risk with each monthly exposure. Consequently, the number of exposures per month may need to be considered when devising IO schedules.

  5. A case-control study evaluating relative risk factors for decompression sickness: a research report. (United States)

    Suzuki, Naoko; Yagishita, Kazuyosi; Togawa, Seiichiro; Okazaki, Fumihiro; Shibayama, Masaharu; Yamamoto, Kazuo; Mano, Yoshihiro


    Factors contributing to the pathogenesis of decompression sickness (DCS) in divers have been described in many studies. However, relative importance of these factors has not been reported. In this case-control study, we compared the diving profiles of divers experiencing DCS with those of a control group. The DCS group comprised 35 recreational scuba divers who were diagnosed by physicians as having DCS. The control group consisted of 324 apparently healthy recreational divers. All divers conducted their dives from 2009 to 2011. The questionnaire consisted of 33 items about an individual's diving profile, physical condition and activities before, during and just after the dive. To simplify dive parameters, the dive site was limited to Izu Osezaki. Odds ratios and multiple logistic regression were used for the analysis. Odds ratios revealed several items as dive and health factors associated with DCS. The major items were as follows: shortness of breath after heavy exercise during the dive (OR = 12.12), dehydration (OR = 10.63), and maximum dive depth > 30 msw (OR = 7.18). Results of logistic regression were similar to those by odds ratio analysis. We assessed the relative weights of the surveyed dive and health factors associated with DCS. Because results of several factors conflict with previous studies, future studies are needed.

  6. The r-process nucleosynthesis during the decompression of neutron star crust material

    Energy Technology Data Exchange (ETDEWEB)

    Goriely, S. [Institut d' Astronomie et d' Astrophysique, CP-226, Université Libre de Bruxelles, 1050 Brussels (Belgium); Bauswein, A. [Department of Physics, Aristotle University of Thessaloniki, 54124 Thessaloniki, Greece and Max-Planck-Institut für Astrophysik, Postfach 1317, 85741 Garching (Germany); Janka, H.-T. [Max-Planck-Institut für Astrophysik, Postfach 1317, 85741 Garching (Germany); Sida, J.-L.; Lemaître, J.-F.; Panebianco, S. [C.E.A. Saclay, Irfu/Service de Physique Nucléaire, 91191 Gif-sur-Yvette (France); Dubray, N.; Hilaire, S. [CEA, DAM, DIF, F-91297 Arpajon (France)


    About half of the nuclei heavier than iron observed in nature are produced by the so-called rapid neutron capture process, or r-process, of nucleosynthesis. The identification of the astrophysics site and the specific conditions in which the r-process takes place remains, however, one of the still-unsolved mysteries of modern astrophysics. Another underlying difficulty associated with our understanding of the r-process concerns the uncertainties in the predictions of nuclear properties for the few thousands exotic neutron-rich nuclei involved, for which essentially no experimental data exist. The present paper emphasizes some important future challenges faced by nuclear physics in this problem, particularly in the determination of the nuclear structure properties of exotic neutron-rich nuclei as well as their radiative neutron capture rates and their fission probabilities. These quantities are particularly relevant to determine the composition of the matter resulting from the r-process. Both the astrophysics and the nuclear physics difficulties are critically reviewed with special attention paid to the r-process taking place during the decompression of neutron star matter following the merging of two neutron stars.

  7. Hemilingual spasm: defining a new entity, its electrophysiological correlates and surgical treatment through microvascular decompression. (United States)

    Osburn, Leisha L; Møller, Aage R; Bhatt, Jay R; Cohen-Gadol, Aaron A


    We report on vascular compression syndrome of the 12th cranial nerve (hypoglossal), an occurrence not previously reported, and demonstrate, through corresponding objective electrophysiological evidence, that microvascular decompression of the hypoglossal nerve root can cure hemilingual spasm. A 52-year-old man had lower face muscle twitching and tongue spasms, which worsened with talking, chewing, or emotional stress. Carbamazepine offered only temporary relief, and relief from injections of botulinum toxin was insignificant. He was referred for surgical treatment. High-resolution magnetic resonance imaging of his posterior fossa contents revealed no obvious evidence of any compressive vessel along the facial nerve, but a compressive vessel along the hypoglossal nerve was apparent. The presence of preoperative tongue spasms encouraged interoperative monitoring of tongue motor responses. The facial nerve exit zone was explored, but microsurgical inspection of the seventh/eighth cranial nerve complex did not reveal any compressive vessel. However, at the anterolateral aspect of the medulla oblongata, the hypoglossal nerve was clearly compressed and distorted laterally by a large tortuous vertebral artery. When the artery was mobilized away from the nerve, the abnormal late electromyographic response to transcranial electrical stimulation disappeared; immediately after shredded Teflon was interpositioned between the artery and the nerve, the abnormal spontaneous tongue fasciculation also disappeared. The patient has remained spasm free 6 months after surgery. Hemilingual spasm may be caused by vascular contact/compression along cranial nerve XII at the lower brainstem and belong to the same family of cranial nerve hyperactivity disorders as hemifacial spasm.

  8. Outcome of decompressive craniectomy (DC) for severe traumatic brain injury (stbi) in adults

    International Nuclear Information System (INIS)

    Qasmi, S.A.; Ghaffar, A.; Akram, M.


    To evaluate the outcomes of decompressive craniectomy (DC) in adults with severe traumatic brain injury (STBI). Study Design: Observational cross-sectional. Place and Duration of Study: Neurosurgical unit CMH Rawalpindi from July, 2011 to June 2014. Material and Methods: Total of 39 patients who underwent DC for STBI were included in the study. Patients of both sexes and of age range 20 - 48 (32.03 +- 8.01) years were included in the study. The DC was performed within 24 and after 24 hours. Parameters recorded were mortality, neurological outcome / complications like brain herniation, wound dehiscence, cerebrospinal fluid (CSF) leak, contusion expansion, sinking flap syndrome, subdural hygromas and hydrocephalus. Data was analyzed by using SPSS version 17 and descriptive statistics, frequency, rate and percentage was computed for presentation of qualitative outcomes. Results: Favourable neurological outcome was seen in 21 patients (53.85%) where as 6 patients (15.38%) had moderate to severe disability and 3 patients (7.69%) were vegetative respectively. Patients operated within 24 hours and with Glasgow coma scale (GCS) range 6-8 had better outcome. Overall 9 patients (23.08%) did not survive the injury and procedure. Conclusion: As high mortality is associated with STBI, DC is an effective option to lower down the refractory intracranial hypertension with an acceptable surgical outcome. (author)

  9. CT-guided percutaneous laser disk decompression for cervical and lumbar disk hernia

    International Nuclear Information System (INIS)

    Shimizu, Kanichiro; Koyama, Tutomu; Harada, Junta; Abe, Toshiaki


    Percutaneous laser disk decompression under X-ray fluoroscopy was first reported in 1987 for minimally invasive therapy of lumbar disk hernia. In patients with disk hernia, laser vaporizes a small portion of the intervertebral disk thereby reducing the volume and pressure of the affected disk. We present the efficacy and safety of this procedure, and analysis of fair or poor response cases. In our study, 226 cases of lumbar disk hernia and 7 cases of cervical disk hernia were treated under CT guided PLDD. Japan Orthopedic Association (JOA) score and Mac-Nab criteria were investigated to evaluate the response to treatment. Improvement ratio based on the JOA score was calculated as follows. Overall success rate was 91.6% in cases lumber disk hernia, and 100% in cases of cervical disk hernia. We experienced two cases with two cases with postoperative complication. Both cases were treated conservatively. The majority of acute cases and post operative cases were reported to be 'good' on Mac-Nab criteria. Cases of fair or poor response on Mac-Nab criteria were lateral type, foraminal stenosis or large disk hernia. CT-guided PLDD is a safe and accurate procedure. The overall success rate can be increased by carefully selecting patients. (author)

  10. Temporary Decompression in Critically Ill Patients: Retrospective Comparison of Ileostomy and Colostomy. (United States)

    Lin, Zhi-Liang; Yu, Wen-Kui; Shi, Jia-Liang; Chen, Qi-Yi; Tan, Shan-Jun; Li, Ning


    In critically ill patients, gastrointestinal function plays an important role in multiple organ dysfunction syndrome. Patients suffering from acute lower gastrointestinal dysfunction need to be performed a temporary fecal diversion after the failure of conservative treatment. This study aims to determine which type of fecal diversion is associated with better clinical outcomes in critically ill patients. Data of critically ill patients requiring surgical decompression following acute lower gastrointestinal dysfunction between January 2008 and June 2013 were retrospectively analyzed. Comparison was made between ileostomy group and colostomy group regarding the stoma-related complications and the recovery after stoma creation. 63 patients consisted of temporary ileostomy group (n = 35) and temporary colostomy group (n = 28) were included in this study. First bowel movement and length of enteral nutrition intolerance after fecal diversion were both significantly shorter in the ileostomy group than in the colostomy group (1.70 ± 0.95 vs. 3.04 ± 1.40; p colostomy group. Both procedures provide an effective defunctioning of the distant gastrointestinal tract with a low complication incidence. We prefer a temporary ileostomy to temporary colostomy for acute lower gastrointestinal dysfunction in critically ill patients.

  11. Delayed treatment of decompression sickness with short, no-air-break tables: review of 140 cases. (United States)

    Cianci, Paul; Slade, John B


    Most cases of decompression sickness (DCS) in the U.S. are treated with hyperbaric oxygen using U.S. Navy Treatment Tables 5 and 6, although detailed analysis shows that those tables were based on limited data. We reviewed the development of these protocols and offer an alternative treatment table more suitable for monoplace chambers that has proven effective in the treatment of DCS in patients presenting to our facility. We reviewed the outcomes for 140 cases of DCS in civilian divers treated with the shorter tables at our facility from January 1983 through December 2002. Onset of symptoms averaged 9.3 h after surfacing. At presentation, 44% of the patients demonstrated mental aberration. The average delay from onset of symptoms to treatment was 93.5 h; median delay was 48 h. Complete recovery in the total group of 140 patients was 87%. When 30 patients with low probability of DCS were excluded, the recovery rate was 98%. All patients with cerebral symptoms recovered. Patients with the highest severity scores showed a high rate of complete recovery (97.5%). Short oxygen treatment tables as originally described by Hart are effective in the treatment of DCS, even with long delays to definitive recompression that often occur among civilian divers presenting to a major Divers Alert Network referral center.

  12. MR guidance and thermometry of percutaneous laser disc decompression in open MRI: an initial clinical investigation

    Energy Technology Data Exchange (ETDEWEB)

    Streitparth, Florian; Walter, Thula; Bucourt, Maximilian de; Freyhardt, Patrick; Maurer, Martin; Renz, Diane; Gebauer, Bernhard; Hamm, Bernd; Teichgraeber, Ulf K.M. [Charite, Humboldt-University Medical School, Department of Radiology, Berlin (Germany); Hartwig, Tony; Putzier, Michael; Strube, Patrick [Charite, Humboldt-University, Center for Musculoskeletal Surgery, Berlin (Germany); Bretschneider, Tina [University of Magdeburg, Department of Radiology, Magdeburg (Germany)


    To assess the feasibility, safety and efficacy of real-time MR guidance and thermometry of percutaneous laser disc decompression (PLDD). Twenty-four discs in 22 patients with chronic low-back and radicular pain were treated by PLDD using open 1.0-T magnetic-resonance imaging (MRI). A fluoroscopic proton-density-weighted turbo spin-echo (PDw TSE) sequence was used to position the laser fibre. Non-spoiled gradient-echo (GRE) sequences were employed for real-time thermal monitoring based on proton resonance frequency (PRF). Radicular pain was assessed over 6 months with a numerical rating scale (NRS). PLDD was technically successful in all cases, with adequate image quality for laser positioning. The PRF-based real-time temperature monitoring was found to be feasible in practice. After 6 months, 21 % reported complete remission of radicular pain, 63 % at least great pain relief and 74 % at least mild relief. We found a significant decrease in the NRS score between the pre-intervention and the 6-month follow-up assessment (P < 0.001). No major complications occurred; the single adverse event recorded, moderate motor impairment, resolved. Real-time MR guidance and PRF-based thermometry of PLDD in the lumbar spine under open 1.0-T MRI appears feasible, safe and effective and may pave the way to more precise operating procedures. (orig.)

  13. The Management of Cerebrospinal Fluid Leak After Anterior Cervical Decompression Surgery. (United States)

    Zhai, Jiliang; Panchal, Ripul R; Tian, Ye; Wang, Shujie; Zhao, Lijuan


    Cerebrospinal fluid (CSF) leak is a rare but potentially troublesome and occasionally catastrophic complication after anterior cervical decompression surgery. There is limited literature describing this complication, and the management of CSF leak varies. The aim of this study was to retrospectively review the treatment of cases with CSF leak and develop a management algorithm. A series of 14 patients with CSF leak from January 2011 to May 2016 were included in this study. Their characteristics, management of CSF leak, and outcomes were documented. There were 5 male and 9 female patients. Mean age at surgery was 57.1±9.9 years (range, 37-76 years). All instances of CSF leak, except 1 noted postoperatively, were indirectly repaired intraoperatively. A closed straight wound drain was placed for all patients. A lumbar subarachnoid drain was placed immediately after surgery in 4 patients and postoperatively in 7 patients. In 1 patient, lumbar drain placement was unsuccessful. In 2 additional patients, the surgeon decided not to place a lumbar drain. One patient developed meningitis and recovered after antibiotic therapy with meropenem and vancomycin. Another patient had a deep wound infection and required a revision surgery. Wound drains and lumbar drains should be immediately considered when CSF leak is identified. Antibiotics also should be considered to prevent intradural infection. [Orthopedics. 2018; 41(2):e283-e288.]. Copyright 2018, SLACK Incorporated.

  14. Genetic programs can be compressed and autonomously decompressed in live cells (United States)

    Lapique, Nicolas; Benenson, Yaakov


    Fundamental computer science concepts have inspired novel information-processing molecular systems in test tubes1-13 and genetically encoded circuits in live cells14-21. Recent research has shown that digital information storage in DNA, implemented using deep sequencing and conventional software, can approach the maximum Shannon information capacity22 of two bits per nucleotide23. In nature, DNA is used to store genetic programs, but the information content of the encoding rarely approaches this maximum24. We hypothesize that the biological function of a genetic program can be preserved while reducing the length of its DNA encoding and increasing the information content per nucleotide. Here we support this hypothesis by describing an experimental procedure for compressing a genetic program and its subsequent autonomous decompression and execution in human cells. As a test-bed we choose an RNAi cell classifier circuit25 that comprises redundant DNA sequences and is therefore amenable for compression, as are many other complex gene circuits15,18,26-28. In one example, we implement a compressed encoding of a ten-gene four-input AND gate circuit using only four genetic constructs. The compression principles applied to gene circuits can enable fitting complex genetic programs into DNA delivery vehicles with limited cargo capacity, and storing compressed and biologically inert programs in vivo for on-demand activation.

  15. Radiosurgery of epidermoid tumors with gamma knife. Possiblity of radiosurgical nerve decompression

    International Nuclear Information System (INIS)

    Kida, Yoshihisa; Yoshimoto, Masayuki; Hasegawa, Toshinori; Fujitani, Shigeru


    Long-term results of radiosurgery for epidermoid tumors are reported. There are 7 cases including 2 males and 5 females, ages ranging from 6 to 46 (mean: 33.3 years). At radiosurgery whole tumor was covered in 4 cases and partially covered in 3 cases in attempting to relieve cranial nerve signs like trigeminal neuralgia and facial spasm. The mean maximum and marginal doses were 25.6 Gy and 14.6 Gy respectively. In the mean follow-up of 52.7 months, all the tumors showed good tumor control without any progression and tumor shrinkage has been confirmed in 2 out of the 7 cases. Symptomatic trigeminal neuralgia improved or disappeared in all 4 cases and facial spasm disappeared in one. No neurological deterioration was found in any of the cases after the treatment. In conclusion, it is apparent that epidermoid tumors do respond well to radiosurgery and the accompanying hyperactive dysfunction of cranial nerves is significantly improved by gamma knife treatment with either entire or partial tumor coverage. Therefore the radiosurgical nerve decompression for epidermoid tumor seems to be achieved by gamma-radiosurgery. (author)

  16. MR guidance and thermometry of percutaneous laser disc decompression in open MRI: an initial clinical investigation

    International Nuclear Information System (INIS)

    Streitparth, Florian; Walter, Thula; Bucourt, Maximilian de; Freyhardt, Patrick; Maurer, Martin; Renz, Diane; Gebauer, Bernhard; Hamm, Bernd; Teichgraeber, Ulf K.M.; Hartwig, Tony; Putzier, Michael; Strube, Patrick; Bretschneider, Tina


    To assess the feasibility, safety and efficacy of real-time MR guidance and thermometry of percutaneous laser disc decompression (PLDD). Twenty-four discs in 22 patients with chronic low-back and radicular pain were treated by PLDD using open 1.0-T magnetic-resonance imaging (MRI). A fluoroscopic proton-density-weighted turbo spin-echo (PDw TSE) sequence was used to position the laser fibre. Non-spoiled gradient-echo (GRE) sequences were employed for real-time thermal monitoring based on proton resonance frequency (PRF). Radicular pain was assessed over 6 months with a numerical rating scale (NRS). PLDD was technically successful in all cases, with adequate image quality for laser positioning. The PRF-based real-time temperature monitoring was found to be feasible in practice. After 6 months, 21 % reported complete remission of radicular pain, 63 % at least great pain relief and 74 % at least mild relief. We found a significant decrease in the NRS score between the pre-intervention and the 6-month follow-up assessment (P < 0.001). No major complications occurred; the single adverse event recorded, moderate motor impairment, resolved. Real-time MR guidance and PRF-based thermometry of PLDD in the lumbar spine under open 1.0-T MRI appears feasible, safe and effective and may pave the way to more precise operating procedures. (orig.)

  17. Decompression-induced melting of ice IV and the liquid-liquid transition in water (United States)

    Mishima, Osamu; Stanley, H. Eugene


    Although liquid water has been the focus of intensive research for over 100 years, a coherent physical picture that unifies all of the known anomalies of this liquid, is still lacking. Some of these anomalies occur in the supercooled region, and have been rationalized on the grounds of a possible retracing of the liquid-gas spinodal (metastability limit) line into the supercooled liquid region, or alternatively the presence of a line of first-order liquid-liquid phase transitions in this region which ends in a critical point,. But these ideas remain untested experimentally, in part because supercooled water can be probed only above the homogeneous nucleation temperature TH at which water spontaneously crystallizes. Here we report an experimental approach that is not restricted by the barrier imposed by TH, involving measurement of the decompression-induced melting curves of several high-pressure phases of ice in small emulsified droplets. We find that the melting curve for ice IV seems to undergo a discontinuity at precisely the location proposed for the line of liquid-liquid phase transitions. This is consistent with, but does not prove, the coexistence of two different phases of (supercooled) liquid water. From the experimental data we calculate a possible Gibbs potential surface and a corresponding equation of state for water, from the forms of which we estimate the coordinates of the liquid-liquid critical point to be at pressure Pc ~ 0.1GPa and temperature Tc ~ 220K.


    Institute of Scientific and Technical Information of China (English)

    赵卫国; 沈建康; 成侃; 胡锦清; 濮春华; 卞留贯; 孙青芳; 朱军


    Objective To summarize our clinical experience of microvascular decompression (MVD) for medically intractable hemifacial spasm(HFS) patients with emphasis on microsurgical manipulation and to improve cure rate and avoid surgical complications.MethodsThree hundred and thirty eight patients with HFS underwent MVD under general anesthesia. With the help of "zero retraction" technique, prosthesis can be properly inserted between offending vessel loop and affected facial nerve REZ in a "rolling ball" fashion under operative microscope.ResultsSurgical intervention achieved high relief rate of 91.4% and no major complications, with low recurrence rate of only 3.2% after averaging more than two years follow up (M=32 months).ConclusionIt is possible to approach to the facial nerve REZ with "zero retraction", which is fundamentally important to clear from cranial nerve and cerebellar injury. Skilled microsurgical technique along with correct recognition and mobilization of offending vessels are a must to assure MVD a highly efficacious and low risk treatment of choice for HFS patients.

  19. Isosorbide-Induced Decompression Effect on the Scala Media: Participation of Plasma Osmolality and Plasma Arginine Vasopressin. (United States)

    Takeda, Taizo; Takeda, Setsuko; Uehara, Natsumi; Yanagisawa, Shungaku; Furukawa, Tatsuya; Nibu, Ken-Ichi; Kakigi, Akinobu


    The correlation between the isosorbide-induced decompression effect on the endolymphatic space and plasma osmolality (p-OSM) or plasma arginine vasopressin (p-AVP) was investigated on comparing two different dosages of isosorbide (2.8 and 1.4 g/kg) to elucidate why the decompression effect is delayed with a large dose of isosorbide. Two experiments were performed using 80 guinea pigs. Experiment 1 was designed to morphologically investigate the sequential influence of the oral intake of 1.4- and 2.8-g/kg doses of isosorbide on the endolymphatic volume. The animals used were 50 guinea pigs (control: 10, experimental: 40). All animals underwent surgical obliteration of the endolymphatic sac of the left ear. One month after the surgery, control animals were sacrificed 3 hours after the intake of distilled water, and experimental animals were sacrificed 3 and 6 hours after the isosorbide intake. All of the left temporal bone served for the quantitative assessment of changes in the endolymphatic space, and the cross-sectional area of the scala media was measured from the mid-modiolar sections of the cochlea.Experiment 2 was designed to investigate changes in p-OSM and p-AVP levels 3 hours after the oral intake of isosorbide. Animals used were 15 guinea pigs (control: 5, experimental: 10). The control group received the oral administration of distilled water (4 ml/kg), and the experimental animals were subdivided into two groups consisting of 10 animals each by the dosage of isosorbide (1.4 or 2.8 g/kg). All animals were sacrificed for the measurement of p-OSM and p-AVP concentrations 3 hours after the intake of water or 70% isosorbide solution. Morphologically, an isosorbide-induced decompression effect was noted in animals with both 1.4- and 2.8-g/kg doses of isosorbide. According to the regression analysis, however, the volumetric decrease of the endolymphatic space was more evident in cases with the small dose (1.4 g/kg) 3 hours after the intake

  20. Tonsillar pulsatility before and after surgical decompression for children with Chiari malformation type 1: an application for true fast imaging with steady state precession

    International Nuclear Information System (INIS)

    Radmanesh, Alireza; Greenberg, Jacob K.; Smyth, Matthew D.; Limbrick, David D.; Chatterjee, Arindam; Sharma, Aseem


    We hypothesize that surgical decompression for Chiari malformation type 1 (CM-1) is associated with statistically significant decrease in tonsillar pulsatility and that the degree of pulsatility can be reliably assessed regardless of the experience level of the reader. An Institutional Review Board (IRB)-approved Health Insurance Portability and Accountability Act (HIPAA)-compliant retrospective study was performed on 22 children with CM-1 (8 males; mean age 11.4 years) who had cardiac-gated true-FISP sequence and phase-contrast cerebrospinal fluid (CSF) flow imaging as parts of routine magnetic resonance (MR) imaging before and after surgical decompression. The surgical technique (decompression with or without duraplasty) was recorded for each patient. Three independent radiologists with different experience levels assessed tonsillar pulsatility qualitatively and quantitatively and assessed peritonsillar CSF flow qualitatively. Results were analyzed. To evaluate reliability, Fleiss kappa for multiple raters on categorical variables and intra-class correlation for agreement in pulsatility ratings were calculated. After surgical decompression, the degree of tonsillar pulsatility appreciably decreased, confirmed by t test, both qualitatively (p values <0.001, <0.001, and 0.045 for three readers) and quantitatively (amount of decrease/p value for three readers 0.7 mm/<0.001, 0.7 mm/<0.001, and 0.5 mm/0.022). There was a better agreement among the readers in quantitative assessment of tonsillar pulsatility (kappa 0.753-0.834), compared to qualitative assessment of pulsatility (kappa 0.472-0.496) and qualitative assessment of flow (kappa 0.056 to 0.203). Posterior fossa decompression with duraplasty led to a larger decrease in tonsillar pulsatility, compared to posterior fossa decompression alone. Tonsillar pulsatility in CM-1 is significantly reduced after surgical decompression. Quantitative assessment of tonsillar pulsatility was more reliable across readers than

  1. Tonsillar pulsatility before and after surgical decompression for children with Chiari malformation type 1: an application for true fast imaging with steady state precession

    Energy Technology Data Exchange (ETDEWEB)

    Radmanesh, Alireza [University of California, San Francisco, Department of Radiology and Biomedical Imaging, San Francisco, CA (United States); Washington University School of Medicine, Mallinckrodt Institute of Radiology, St Louis, MO (United States); Greenberg, Jacob K.; Smyth, Matthew D.; Limbrick, David D. [Washington University School of Medicine, Department of Neurosurgery, St Louis, MO (United States); Chatterjee, Arindam; Sharma, Aseem [Washington University School of Medicine, Mallinckrodt Institute of Radiology, St Louis, MO (United States)


    We hypothesize that surgical decompression for Chiari malformation type 1 (CM-1) is associated with statistically significant decrease in tonsillar pulsatility and that the degree of pulsatility can be reliably assessed regardless of the experience level of the reader. An Institutional Review Board (IRB)-approved Health Insurance Portability and Accountability Act (HIPAA)-compliant retrospective study was performed on 22 children with CM-1 (8 males; mean age 11.4 years) who had cardiac-gated true-FISP sequence and phase-contrast cerebrospinal fluid (CSF) flow imaging as parts of routine magnetic resonance (MR) imaging before and after surgical decompression. The surgical technique (decompression with or without duraplasty) was recorded for each patient. Three independent radiologists with different experience levels assessed tonsillar pulsatility qualitatively and quantitatively and assessed peritonsillar CSF flow qualitatively. Results were analyzed. To evaluate reliability, Fleiss kappa for multiple raters on categorical variables and intra-class correlation for agreement in pulsatility ratings were calculated. After surgical decompression, the degree of tonsillar pulsatility appreciably decreased, confirmed by t test, both qualitatively (p values <0.001, <0.001, and 0.045 for three readers) and quantitatively (amount of decrease/p value for three readers 0.7 mm/<0.001, 0.7 mm/<0.001, and 0.5 mm/0.022). There was a better agreement among the readers in quantitative assessment of tonsillar pulsatility (kappa 0.753-0.834), compared to qualitative assessment of pulsatility (kappa 0.472-0.496) and qualitative assessment of flow (kappa 0.056 to 0.203). Posterior fossa decompression with duraplasty led to a larger decrease in tonsillar pulsatility, compared to posterior fossa decompression alone. Tonsillar pulsatility in CM-1 is significantly reduced after surgical decompression. Quantitative assessment of tonsillar pulsatility was more reliable across readers than

  2. Nanobubbles Form at Active Hydrophobic Spots on the Luminal Aspect of Blood Vessels: Consequences for Decompression Illness in Diving and Possible Implications for Autoimmune Disease—An Overview

    Directory of Open Access Journals (Sweden)

    Ran Arieli


    Full Text Available Decompression illness (DCI occurs following a reduction in ambient pressure. Decompression bubbles can expand and develop only from pre-existing gas micronuclei. The different hypotheses hitherto proposed regarding the nucleation and stabilization of gas micronuclei have never been validated. It is known that nanobubbles form spontaneously when a smooth hydrophobic surface is submerged in water containing dissolved gas. These nanobubbles may be the long sought-after gas micronuclei underlying decompression bubbles and DCI. We exposed hydrophobic and hydrophilic silicon wafers under water to hyperbaric pressure. After decompression, bubbles appeared on the hydrophobic but not the hydrophilic wafers. In a further series of experiments, we placed large ovine blood vessels in a cooled high pressure chamber at 1,000 kPa for about 20 h. Bubbles evolved at definite spots in all the types of blood vessels. These bubble-producing spots stained positive for lipids, and were henceforth termed “active hydrophobic spots” (AHS. The lung surfactant dipalmitoylphosphatidylcholine (DPPC, was found both in the plasma of the sheep and at the AHS. Bubbles detached from the blood vessel in pulsatile flow after reaching a mean diameter of ~1.0 mm. Bubble expansion was bi-phasic—a slow initiation phase which peaked 45 min after decompression, followed by fast diffusion-controlled growth. Many features of decompression from diving correlate with this finding of AHS on the blood vessels. (1 Variability between bubblers and non-bubblers. (2 An age-related effect and adaptation. (3 The increased risk of DCI on a second dive. (4 Symptoms of neurologic decompression sickness. (5 Preconditioning before a dive. (6 A bi-phasic mechanism of bubble expansion. (7 Increased bubble formation with depth. (8 Endothelial injury. (9 The presence of endothelial microparticles. Finally, constant contact between nanobubbles and plasma may result in distortion of proteins and their

  3. Use of liposomal bupivacaine in the postoperative management of posterior spinal decompression. (United States)

    Grieff, Anthony N; Ghobrial, George M; Jallo, Jack


    OBJECTIVE The aim in this paper was to evaluate the efficacy of long-acting liposomal bupivacaine in comparison with bupivacaine hydrochloride for lowering postoperative analgesic usage in the management of posterior cervical and lumbar decompression and fusion. METHODS A retrospective cohort-matched chart review of 531 consecutive cases over 17 months (October 2013 to February 2015) for posterior cervical and lumbar spinal surgery procedures performed by a single surgeon (J.J.) was performed. Inclusion criteria for the analysis were limited to those patients who received posterior approach decompression and fusion for cervical or lumbar spondylolisthesis and/or stenosis. Patients from October 1, 2013, through December 31, 2013, received periincisional injections of bupivacaine hydrochloride, whereas after January 1, 2014, liposomal bupivacaine was solely administered to all patients undergoing posterior approach cervical and lumbar spinal surgery through the duration of treatment. Patients were separated into 2 groups for further analysis: posterior cervical and posterior lumbar spinal surgery. RESULTS One hundred sixteen patients were identified: 52 in the cervical cohort and 64 in the lumbar cohort. For both cervical and lumbar cases, patients who received bupivacaine hydrochloride required approximately twice the adjusted morphine milligram equivalent (MME) per day in comparison with the liposomal bupivacaine groups (5.7 vs 2.7 MME, p = 0.27 [cervical] and 17.3 vs 7.1 MME, p = 0.30 [lumbar]). The amounts of intravenous rescue analgesic requirements were greater for bupivacaine hydrochloride in comparison with liposomal bupivacaine in both the cervical (1.0 vs 0.39 MME, p = 0.31) and lumbar (1.0 vs 0.37 MME, p = 0.08) cohorts as well. None of these differences was found to be statistically significant. There were also no significant differences in lengths of stay, complication rates, or infection rates. A subgroup analysis of both cohorts of opiate-naive versus

  4. Percutaneous laser disc decompression versus conventional microdiscectomy in sciatica: a randomized controlled trial. (United States)

    Brouwer, Patrick A; Brand, Ronald; van den Akker-van Marle, M Elske; Jacobs, Wilco C H; Schenk, Barry; van den Berg-Huijsmans, Annette A; Koes, Bart W; van Buchem, M A; Arts, Mark P; Peul, Wilco C


    Percutaneous laser disc decompression (PLDD) is a minimally invasive treatment for lumbar disc herniation, with Food and Drug Administration approval since 1991. However, no randomized trial comparing PLDD to conventional treatment has been performed. In this trial, we assessed the effectiveness of a strategy of PLDD as compared with conventional surgery. This randomized prospective trial with a noninferiority design was carried out in two academic and six teaching hospitals in the Netherlands according to an intent-to-treat protocol with full institutional review board approval. One hundred fifteen eligible surgical candidates, with sciatica from a disc herniation smaller than one-third of the spinal canal, were included. The main outcome measures for this trial were the Roland-Morris Disability Questionnaire for sciatica, visual analog scores for back and leg pain, and the patient's report of perceived recovery. Patients were randomly allocated to PLDD (n=57) or conventional surgery (n=58). Blinding was impossible because of the nature of the interventions. This study was funded by the Healthcare Insurance Board of the Netherlands. The primary outcome, Roland-Morris Disability Questionnaire, showed noninferiority of PLDD at 8 (-0.1; [95% confidence interval (CI), -2.3 to 2.1]) and 52 weeks (-1.1; 95% CI, -3.4 to 1.1) compared with conventional surgery. There was, however, a higher speed of recovery in favor of conventional surgery (hazard ratio, 0.64 [95% CI, 0.42-0.97]). The number of reoperations was significantly less in the conventional surgery group (38% vs. 16%). Overall, a strategy of PLDD, with delayed surgery if needed, resulted in noninferior outcomes at 1 year. At 1 year, a strategy of PLDD, followed by surgery if needed, resulted in noninferior outcomes compared with surgery. Copyright © 2015 Elsevier Inc. All rights reserved.

  5. National Survey of Neurosurgeons and Stroke Physicians on Decompressive Hemicraniectomy for Malignant Middle Cerebral Artery Infarction. (United States)

    Basu, Pallavi; Jenkins, Harri; Tsang, Kevin; Vakharia, Vejay N


    Several studies have evaluated the use of decompressive hemicraniectomy (DHC) in malignant middle cerebral artery infarction (MMCAI). In the United Kingdom, the National Institute for Health and Care Excellence (NICE) has set criteria for selection of patients for DHC in MMCAI. We set out to survey the attitudes and practice of neurosurgeons and stroke physicians within the United Kingdom towards DHC in MMCAI. An electronic survey of questions on management of MMCAI in various clinical scenarios was submitted to the academic committees of the Society of British Neurological Surgeons and the British Association of Stroke Physicians for approval before dissemination through the consultant members. Responses were collected over 2 months. A total of 78 responses, from 51 neurosurgeons and 27 stroke physicians, were included in final analysis. A total of 54% and 24% of all respondents would recommend DHC in patients aged 60-70 and 70-80 years, respectively; 60% would advocate surgery between 48 and 72 hours and 27% beyond 72 hours. A total of 36% indicated DHC with preoperative Glasgow Coma Scale 15/15. These findings do not conform to current NICE guidelines. Stroke physicians were statistically more likely to recommend DHC in patients older than 60 years (P = 0.032) and in those with dominant multiterritorial infarcts (P = 0.042) and accept a greater postoperative modified Rankin Scale (P = 0.034) compared with neurosurgeons. In view of evidence from recent trials and differences in NICE guidelines and current clinical practice within the United Kingdom, based on our survey results, it is important to reevaluate NICE guidelines. Crown Copyright © 2017. Published by Elsevier Inc. All rights reserved.

  6. Pulmonary decompression sickness at altitude: early symptoms and circulating gas emboli (United States)

    Balldin, Ulf I.; Pilmanis, Andrew A.; Webb, James T.


    INTRODUCTION: Pulmonary altitude decompression sickness (DCS) is a rare condition. 'Chokes' which are characterized by the triad of substernal pain, cough, and dyspnea, are considered to be associated with severe accumulation of gas bubbles in the pulmonary capillaries and may rapidly develop into a life-threatening medical emergency. This study was aimed at characterizing early symptomatology and the appearance of venous gas emboli (VGE). METHODS: Symptoms of simulated-altitude DCS and VGE (with echo-imaging ultrasound) were analyzed in 468 subjects who participated in 22 high altitude hypobaric chamber research protocols from 1983 to 2001 at Brooks Air Force Base, TX. RESULTS: Of 2525 subject-exposures to simulated altitude, 1030 (41%) had symptoms of DCS. Only 29 of those included DCS-related pulmonary symptoms. Of these, only 3 subjects had all three pulmonary symptoms of chokes; 9 subjects had two of the pulmonary symptoms; and 17 subjects had only one. Of the 29 subject-exposures with pulmonary symptoms, 27 had VGE and 21 had severe VGE. The mean onset times of VGE and symptoms in the 29 subject-exposures were 42 +/- 30 min and 109 +/- 61 min, respectively. In 15 subjects, the symptoms disappeared during recompression to ground level followed by 2 h of oxygen breathing. In the remaining 14 cases, the symptoms disappeared with immediate hyperbaric oxygen treatment. CONCLUSIONS: Pulmonary altitude DCS or chokes is confirmed to be a rare condition. Our data showed that when diagnosed early, recompression to ground level pressure and/or hyperbaric oxygen treatment was 100% successful in resolving the symptoms.

  7. Central nervous system decompression sickness and venous gas emboli in hypobaric conditions. (United States)

    Balldin, Ulf I; Pilmanis, Andrew A; Webb, James T


    Altitude decompression sickness (DCS) that involves the central nervous system (CNS) is a rare but potentially serious condition. Identification of early symptoms and signs of this condition might improve treatment. We studied data from 26 protocols carried out in our laboratory over the period 1983-2003; all were designed to provoke DCS in a substantial proportion of subjects. The data set included 2843 cases. We classified subject-exposures that resulted in DCS as: 1) neurological DCS of peripheral and/or central origin (NEURO); 2) a subset of those that involved only the CNS (CNS); and 3) all other cases, i.e., DCS cases that did not have a neurological component (OTHER). For each case, echo imaging data were used to document whether venous gas emboli (VGE) were present, and their level was classified as: 1) any level, i.e., Grade 1 or higher (VGE-1); and 2) high level, Grade 4 (VGE-4). There were 1108 cases of altitude DCS in the database; 218 were classified as NEURO and 49 of those as CNS. VGE-1 were recorded in 83.8% of OTHER compared with 58.7% of NEURO and 55.1% of CNS (both p Hyperbaric oxygen (HBO) was used to treat about half of the CNS cases, while all other cases were treated with 2 h breathing 100% oxygen at ground level. Since only about half of the rare cases of hypobaric CNS DCS cases were accompanied by any level of VGE, echo imaging for bubbles may have limited application for use as a predictor of such cases.

  8. Use of autologous bone graft in anterior cervical decompression: morbidity & quality of life analysis.

    LENUS (Irish Health Repository)

    Heneghan, Helen M


    BACKGROUND: Autologous iliac crest graft has long been the gold standard graft material used in cervical fusion. However its harvest has significant associated morbidity, including protracted postoperative pain scores at the harvest site. Thus its continued practice warrants scrutiny, particularly now that alternatives are available. Our aims were to assess incidence and nature of complications associated with iliac crest harvest when performed in the setting of Anterior Cervical Decompression (ACD). Also, to perform a comparative analysis of patient satisfaction and quality of life scores after ACD surgeries, when performed with and without iliac graft harvest. METHODS: All patients who underwent consecutive ACD procedures, with and without the use of autologous iliac crest graft, over a 48 month period were included (n = 53). Patients were assessed clinically at a minimum of 12 months postoperatively and administered 2 validated quality of life questionnaires: the SF-36 and Cervical Spine Outcomes Questionnaires (Response rate 96%). Primary composite endpoints included incidence of bone graft donor site morbidity, pain scores, operative duration, and quality of life scores. RESULTS: Patients who underwent iliac graft harvest experienced significant peri-operative donor site specific morbidity, including a high incidence of pain at the iliac crest (90%), iliac wound infection (7%), a jejunal perforation, and longer operative duration (285 minutes vs. 238 minutes, p = 0.026). Longer term follow-up demonstrated protracted postoperative pain at the harvest site and significantly lower mental health scores on both quality of life instruments, for those patients who underwent autologous graft harvest CONCLUSION: ACD with iliac crest graft harvest is associated with significant iliac crest donor site morbidity and lower quality of life at greater than 12 months post operatively. This is now avoidable by using alternatives to autologous bone without compromising clinical

  9. Cortical Reorganization Is Associated with Surgical Decompression of Cervical Spondylotic Myelopathy

    Directory of Open Access Journals (Sweden)

    Andrew Green


    Full Text Available Background. Cervical spondylotic myelopathy (CSM results in sensorimotor limb deficits, bladder, and bowel dysfunction, but mechanisms underlying motor plasticity changes before and after surgery are unclear. Methods. We studied 24 patients who underwent decompression surgery and 15 healthy controls. Patients with mixed upper and lower limb dysfunction (Group A and only lower limb dysfunction (Group B were then analysed separately. Results. The sum amplitude of motor evoked potentials sMEP (p<0.01 and number of focal points where MEPs were elicited (N (p<0.001 were significantly larger in CSM patients compared with controls. For Group A (16 patients, sMEP (p<0.01 and N (p<0.001 showed similar findings. However, for Group B (8 patients, only N (p=0.03 was significantly larger in patients than controls. Group A had significantly increased grip strength (p=0.02 and reduced sMEP (p=0.001 and N (p=0.003 after surgery. Changes in sMEP (cMEP significantly correlated inversely with improved feeding (p=0.03 and stacking (p=0.04 times as was the change in number of focal points (NDiff with improved writing times (p=0.03. Group B did not show significant reduction in sMEP or N after surgery, or significant correlation of cMEP or NDiff with all hand function tests. No significant differences in H reflex parameters obtained from the flexor carpi radialis, or central motor conduction time changes, were noted after surgery. Discussion. Compensatory expansion of motor cortical representation occurs largely at cortical rather than spinal levels, with a tendency to normalization after surgery. These mirrored improvements in relevant tasks requiring utilization of intrinsic hand muscles.

  10. Decompressive Craniectomy for Acute Subdual Haematoma with Expansile Duraplasty Versus Dura-Slits

    International Nuclear Information System (INIS)

    Khan, B.; Afridi, E. A. K.; Khan, S. A.; Aurangzeb, A.; Khan, A. A.; Khan, W.; Bhatti, S. N.; Khan, B.


    Background: Traumatic subdural hematoma is one of the lethal injuries to brain. Various surgical techniques are used to evacuate the acute subdural hematoma. The hematoma evacuation can either be done by opening of dura by multiple slits or by opening of dura in single large c shape and then doing the expansile duraplasty. Present study aimed to compare both these techniques. Methods: This randomized control study was conducted in department of neurosurgery, Ayub Medical College, Abbottabad from July 2011 to July 2013. A total of 59 patients were included in this study, which were randomly allocated in two groups (i.e., group A and group B) for decompressive craniectomy. Thirty-one patients were operated by craniectomy with full dural flap opening (Group A), and 28 patients were operated by craniectomy with multidural-slits (Group B). Glasgow Outcome score (GOS) at 6 weeks after the surgery was used to determine the outcome. Results: Mean age of the patients was 33.4±12.8 years. Majority were males. In group A 51.6 percent (16) of the patients survived out of which a favourable outcome (GOC 3-5) was observed in 41.9 percent of the patients, and 9.1 percent of patients ended up in vegetative state. While in group B 46.4 percent (13) of the patients survived among which favourable outcome was seen in 39.3 percent of patients and 7.1 percent of patients ended up in vegetative state. The difference in outcome measure is insignificant. Conclusion: There was no statistically significant difference among the two groups as regards the mortality, GOS, frequency of complications and hospital. While the duration of surgery was significantly shorter in patients operated with dural slits. (author)

  11. Reduced CSF leak in complete calvarial reconstructions of microvascular decompression craniectomies using calcium phosphate cement. (United States)

    Eseonu, Chikezie I; Goodwin, C Rory; Zhou, Xin; Theodros, Debebe; Bender, Matthew T; Mathios, Dimitrios; Bettegowda, Chetan; Lim, Michael


    Calcium phosphate cement provides a biomaterial that can be used for calvarial reconstruction in a retrosigmoid craniectomy for microvascular decompression (MVD). This study evaluates the outcomes of postoperative CSF leak and wound infection for patients undergoing a complete cranioplasty using calcium phosphate cement versus incomplete cranioplasty using polyethylene titanium mesh following a retrosigmoid craniectomy for MVD. The authors evaluated 211 cases involving patients who underwent first-time retrosigmoid craniectomies performed by a single attending surgeon fortrigeminal neuralgia from October 2008 to June 2014. From this patient population, 111 patients underwent calvarial reconstruction after retrosigmoid craniectomy using polyethylene titanium mesh, and 100 patients had reconstructions using calcium phosphate cement. A Pearson's chi-square test was used to compare postoperative complications of CSF leak and wound infection in these 2 types of cranioplasties. The polyethylene titanium mesh group included 5 patients (4.5%) with postoperative CSF leak or pseudomeningocele and 3 patients (2.7%) with wound infections. In the calcium phosphate cement group, no patients had a CSF leak, and 2 patients (2%) had wound infections. This represented a statistically significant reduction of postoperative CSF leak in patients who underwent calcium phosphate reconstructions of their calvarial defect compared with those who underwent polyethylene titanium mesh reconstructions (p = 0.03). No significant difference was seen between the 2 groups in the number of patients with postoperative wound infections. Calcium phosphate cement provides a viable alternative biomaterial for calvarial reconstruction of retrosigmoid craniectomy defects in patients who have an MVD. The application of this material provides a biocompatible barrier that reduces the incidence of postoperative CSF leaks.

  12. Endolymphatic Sac Decompression With Intra-Sac Dexamethasone Injection in Menière's Disease. (United States)

    Bojrab, Dennis I; LaRouere, Michael J; Bojrab, Dennis I; Babu, Seilesh C; Sargent, Eric W; Chan, Eleanor Y; Hong, Robert S


    Endolymphatic sac decompression surgery (ELSD) may be used to treat patients who have Menière's 's disease refractory to medical therapy. In this study, we investigated whether or not the injection of steroid into the endolymphatic sac at the time of ELSD provides additional benefit to patient outcomes. Randomized prospective single-blinded placebo-controlled study. Tertiary center. Patients with Menière's disease with poorly controlled vertigo despite medical therapy and serviceable hearing that were offered ELSD. Patients randomized into two groups, with control group (n = 17) undergone ELSD without steroid injection and experimental group undergone ELSD with steroid injection (n = 18) MAIN OUTCOME MEASURE(S):: Audiogram, dizziness handicap inventory, tinnitus handicap inventory, frequency of vertigo spells, functional level scale, and quality of life were obtained at multiple intervals from preoperatively to 24 months postoperatively. ELSD resulted in a statistically significant improvement in vertigo control whether or not steroid was injected into the endolymphatic sac at the time of surgery. However, no additional benefit was observed with the addition of intra-sac steroid injection. No statistical difference in pure-tone average, tinnitus handicap inventory, dizziness handicap inventory, or quality of life was observed between the steroid and nonsteroid surgical groups up to 24 months postoperatively. ELSD is an effective treatment for Menière's disease refractory to medical therapy; however, the addition of intra-sac steroid injection at the time of surgery does not seem to result in a further improvement in patient outcomes.

  13. Efficacy of Core Decompression of Femoral Head to Treat Avascular Necrosis in Intravenous Drug Users

    Directory of Open Access Journals (Sweden)

    Hossein Soleimani


    Full Text Available Core decompression (CD of the femoral head is one of the effective treatments of avascular necrosis (AVN, especially in the early stages of the disease. To investigate further the value of CD in treating the AVN, this study was performed on patients with symptomatic AVN with different etiologies who were treated with CD. This study was carried out on 25 patients (with the total number of 37 femoral head who were diagnosed AVN using X-Ray and MRI. The CD treatments for these patients were started soon after the diagnosis. The results were considered as a success if there was no progression of disease confirmed by X Ray or no subsequent operation was required. Modified Ficat staging was used to record changes before and 2 years after CD treatment. Twenty five patients were participated in this study in which 68% (n=17 were female, 32% (n=8 were male, and the average of the age of the patients were 29.58±4.58. Eight of these patients had systemic lupus erythematous (SLE (32%, 4 rheumatoid arthritis (RA (16%, 3 with kidney transplant (12%, 1 Takayasu’s vasculitis (4% and 1 Wegner vasculitis (4%. Eight of patients had a history of intravenous injection of Temgesic (32%. In patients using Temgesic the changes in Modified Ficat staging were significantly different before and after CD treatment (P=0.03 in comparison with other groups. And in all 8 Temgesic users AVN progressed to the stage 3 and 4 after CD treatment. This study demonstrated that CD treatment to prevent the changes in the femoral head has been more effective in patients with collagen vascular diseases and kidney transplant than patients using intravenous Temgesic. These patients, in spite of early operation, showed no benefit of CD to prevent the changes in the femoral head.

  14. Effect of surgical decompression of spinal metastases in acute treatment - Predictors of neurological outcome. (United States)

    Hohenberger, Christoph; Schmidt, Corinna; Höhne, Julius; Brawanski, Alexander; Zeman, Florian; Schebesch, Karl-Michael


    Space-occupying spinal metastases (SM), commonly diagnosed because of acute neurological deterioration, consequently lead to immediate decompression with tumor removal or debulking. In this study, we analyzed a series of patients with surgically treated spinal metastases and explicitly sought to determine individual predictors of functional outcome. 94 patients (26 women, 68 men; mean age 64.0 years) with spinal metastases, who had been surgically treated at our department, were included retrospectively. We reviewed the pre- and postoperative charts, surgical reports, radiographic data for demographics, duration of symptoms, histopathology, stage of systemic disease, co-morbidities, radiographic extension, surgical strategy, neurological performance (Frankel Grade Classification), and the Karnofsky Performance Index (KPI). Emergency surgery within KPI was 60% at admission that had significantly improved at discharge (KPI 70%; p = 0.01). The rate of complications without revision was 4.3%, the revision rate 4.2%. From admission to discharge, pain had been significantly reduced (p = 0.019) and motor deficits significantly improved (p = 0.003). KPI had been significantly improved during in-hospital treatment (median 60 vs 70, p = 0.010). In the multivariable analysis, predictors of poor outcome (KPI < 70) were male sex, multiple metastases, and pre-existing bowel and bladder dysfunction. Median follow up was 2 months. In our series, surgery for spinal metastases (laminectomy, tumor removal, and mass reduction) significantly reduced pain as well as sensory and motor deficits. We identified male sex, multiple metastases, and pre-existing bowel and bladder dysfunction as predictors of negative outcome. Copyright © 2018 Elsevier Ltd. All rights reserved.

  15. Surgical outcome of anterior decompression, grafting and fixation in caries of dorsolumbar spine

    International Nuclear Information System (INIS)

    Wadd, H.I.


    To evaluate the surgical outcome of anterior decompression, grafting and fixation in tuberculosis of the dorsal and lumbar spine with compression over the neural tissue and neural deficit. Study Design: A case series. Place and Duration of Study: Department of Neurosurgery Unit-I, Lahore General Hospital, Lahore, from January 2008 to March 2012. Methodology: Patients with caries spine having compression over the thecal sac with neurological deficit and kyphosis were included in the study. Patients below 17 years and above 56 years of age; those with bed sores and unfit for anesthesia were excluded from the study. Complete blood picture with ESR, X-rays of chest and of the relevant spinal level, and MRI were done. All patients were treated with corpectomy, debridement, drainage of abscess and grafting followed by fixation with poly-axial screws and rods. All patients were assessed by ASIA Impairment Scale before and after surgery and with Bridwell grading after surgery. Results: Among 79 patients, 47 were males and 32 females. The mean age was 35.97 ± 8.8 years. The commonest level involved was the dorsolumbar junction (n=42, 53.16%). Lower limb power improved to ambulatory level in 60% of patients with complete paraplegia; recovery was excellent in patients with partial weakness; only 2 patients (2.53%) deteriorated to a lower grade. There was no postoperative mortality. One patient had long ICU stay due to lung injury. Conclusion: Corpectomy followed by grafting and fixation is safe and effective procedure for dorsolumbar spinal caries. Even those patients presenting with complete paraplegia showed improvement in motor power to ambulatory level and those who had partial deficit showed excellent improvement. (author)

  16. Anterior cervical decompression and fusion on neck range of motion, pain, and function: a prospective analysis. (United States)

    Landers, Merrill R; Addis, Kate A; Longhurst, Jason K; Vom Steeg, Bree-lyn; Puentedura, Emilio J; Daubs, Michael D


    Intractable cervical radiculopathy secondary to stenosis or herniated nucleus pulposus is commonly treated with an anterior cervical decompression and fusion (ACDF) procedure. However, there is little evidence in the literature that demonstrates the impact such surgery has on long-term range of motion (ROM) outcomes. The objective of this study was to compare cervical ROM and patient-reported outcomes in patients before and after a 1, 2, or 3 level ACDF. Prospective, nonexperimental. Forty-six patients. The following were measured preoperatively and also at 3 and 6 months after ACDF: active ROM (full and painfree) in three planes (ie, sagittal, coronal, and horizontal), pain visual analog scale, Neck Disability Index, and headache frequency. Patients undergoing an ACDF for cervical radiculopathy had their cervical ROM measured preoperatively and also at 3 and 6 months after the procedure. Neck Disability Index and pain visual analog scale values were also recorded at the same time. Both painfree and full active ROM did not change significantly from the preoperative measurement to the 3-month postoperative measurement (ps>.05); however, painfree and full active ROM did increase significantly in all three planes of motion from the preoperative measurement to the 6-month postoperative measurement regardless of the number of levels fused (ps≤.023). Visual analog scale, Neck Disability Index, and headache frequency all improved significantly over time (ps≤.017). Our results suggest that patients who have had an ACDF for cervical radiculopathy will experience improved ROM 6 months postoperatively. In addition, patients can expect a decrease in pain, an improvement in neck function, and a decrease in headache frequency. Copyright © 2013 Elsevier Inc. All rights reserved.

  17. Surgical decompression for space-occupying cerebral infarction (the Hemicraniectomy After Middle Cerebral Artery infarction with Life-threatening Edema Trial [HAMLET]): a multicentre, open, randomised trial. (United States)

    Hofmeijer, Jeannette; Kappelle, L Jaap; Algra, Ale; Amelink, G Johan; van Gijn, Jan; van der Worp, H Bart


    Patients with space-occupying hemispheric infarctions have a poor prognosis, with case fatality rates of up to 80%. In a pooled analysis of randomised trials, surgical decompression within 48 h of stroke onset reduced case fatality and improved functional outcome; however, the effect of surgery after longer intervals is unknown. The aim of HAMLET was to assess the effect of decompressive surgery within 4 days of the onset of symptoms in patients with space-occupying hemispheric infarction. Patients with space-occupying hemispheric infarction were randomly assigned within 4 days of stroke onset to surgical decompression or best medical treatment. The primary outcome measure was the modified Rankin scale (mRS) score at 1 year, which was dichotomised between good (0-3) and poor (4-6) outcome. Other outcome measures were the dichotomy of mRS score between 4 and 5, case fatality, quality of life, and symptoms of depression. Analysis was by intention to treat. This trial is registered, ISRCTN94237756. Between November, 2002, and October, 2007, 64 patients were included; 32 were randomly assigned to surgical decompression and 32 to best medical treatment. Surgical decompression had no effect on the primary outcome measure (absolute risk reduction [ARR] 0%, 95% CI -21 to 21) but did reduce case fatality (ARR 38%, 15 to 60). In a meta-analysis of patients in DECIMAL (DEcompressive Craniectomy In MALignant middle cerebral artery infarction), DESTINY (DEcompressive Surgery for the Treatment of malignant INfarction of the middle cerebral arterY), and HAMLET who were randomised within 48 h of stroke onset, surgical decompression reduced poor outcome (ARR 16%, -0.1 to 33) and case fatality (ARR 50%, 34 to 66). Surgical decompression reduces case fatality and poor outcome in patients with space-occupying infarctions who are treated within 48 h of stroke onset. There is no evidence that this operation improves functional outcome when it is delayed for up to 96 h after stroke onset

  18. Decompressive craniectomy for acute subdural haematoma: An overview of current prognostic factors and a discussion about some novel prognostic parametres

    International Nuclear Information System (INIS)

    Kalayci, M.; Gul, S.; Edebali, N.; Acikgoz, B.; Aktunc, E.; Hanci, V.; Cagavi, F.


    Objective: To identify specific factors that can be used to predict functional outcome and to assess the value of decompressive craniectomy in patients with acute subdural haematoma. Methods: The retrospective study was done at the Zonguldak Karaelwas University Practice and Research Hospital, Turkey, and included 34 trauma patients who had undergone decompressive craniectomy for acute subdural haematoma from 2001 to 2009. At the 30th day of the operation, the patients were grouped as survivors and non-survivors. Besides, based on their Glasgow Outcome Scale, which was calculated 6 months post-operatively, the patients were divided into two functional groups: favourable outcomes (4-5 on the scale), and unfavourable outcomes (1-3 on the scale). The characteristics of the groups were compared using SPSS 15 for statistical analysis. Results: One-month mortality was 38.2% (n=13) and 6-month total mortality reached 47% (n=16). Patients with higher pre-operative revised trauma score, Glasgow coma scale, partial anterial pressure of carbon dioxide, arterial oxygen pressure, Charlson co-morbidity index score, blood glucose level, blood urea nitrogen, and lower age had a higher rate of survival and consequently a favourable outcome. Higher platelet values were only found to be a determinant of higher survival at the end of the first month without having any significant effect on the favourable outcome. Conclusion: In patients of traumatic acute subdural haematoma whose Glasgow coma scale on arrival was < 8, a massive craniectomy along with the evacuation of the haematoma, may be considered as a treatment option for intra-operative and post-operative brain swelling. But in patients with a score of 3 on arrival and bilaterally fixed and dilated pupils, decompressive craniectomy is unnecessary. (author)

  19. [Treatment of thoracolumbar burst fracture with lateral anterior decompression, internal fixation with Ventrofix and bone graft with titanic mesh]. (United States)

    Zhang, Shi-min; Zhang, Zhao-jie; Liu, Yu-zhang; Zhang, Lu-tang; Li, Xing


    To discuss the efficacy of lateral anterior decompression, internal fixation with Ventrofix and bone graft with titanic mesh in the treatment of severe thoracolumbar burst fracture. From January 2008 to January 2010, 21 patients with severe thoracolumbar burst fracture were treated with lateral anterior decompression, internal fixation with Ventrofix, bone graft with titanic mesh. There were 15 males and 6 females, ranging in age from 21 to 46 years with an average of 32.2 years. Segment of fracture: 3 cases were in T11, 6 cases in T12, 7 cases in L1, 5 cases in L2. The mean kyphosis angle was 20.1 degrees and loading of fracture was 7.8 scores. Twenty-one cases accompany with incomplete paralysis. Nerves functions were observed according to Frankel grade; correction and maintain of kyphosis angle were observed by X-rays and CT. All the patients were followed up from 12 to 34 months with an average of 18.5 years. Postoperative complication including injury of pleura in 1 case, dynamic ileus in 2 cases, ilioinguinal nerve injury in 1 case, faulty union of wound in 1 case. All the above complications got recovery after symptomatic treatment. The mean kyphosis angle in fusional segment were 4.2 degrees and the rate of correction was 79%. Nerves functions of all patients got improvement and no internal fixation fail, kyphosis angle obviously lost, titanium mesh shifting, loosening and breakage of screw were found at final follow-up. Lateral anterior decompression, bone graft with titanic mesh, internal fixation with Ventrofix is an idea technique for severe thoracolumber burst fracture, but the method can not be used for patient with severity osteoporosis.

  20. [The "window" surgical exposure strategy of the upper anterior cervical retropharyngeal approach for anterior decompression at upper cervical spine]. (United States)

    Wu, Xiang-Yang; Zhang, Zhe; Wu, Jian; Lü, Jun; Gu, Xiao-Hui


    To investigate the "window" surgical exposure strategy of the upper anterior cervical retropharyngeal approach for the exposure and decompression and instrumentation of the upper cervical spine. From Jan. 2000 to July 2008, 5 patients with upper cervical spinal injuries were treated by surgical operation included 4 males and 1 female with and average age of 35 years old ranging from 16 to 68 years. There were 2 cases of Hangman's fractures (type II ), 2 of C2.3 intervertebral disc displacement and 1 of C2 vertebral body tuberculosis. All patients underwent the upper cervical anterior retropharyngeal approach through the "window" between the hypoglossal nerve and the superior laryngeal nerve and pharynx and carotid artery. Two patients of Hangman's fractures underwent the C2,3 intervertebral disc discectomy, bone graft fusion and internal fixation. Two patients of C2,3 intervertebral disc displacement underwent the C2,3 intervertebral disc discectomy, decompression bone graft fusion and internal fixation. One patient of C2 vertebral body tuberculosis was dissected and resected and the focus and the cavity was filled by bone autografting. C1 anterior arch to C3 anterior vertebral body were successful exposed. Lesion resection or decompression and fusion were successful in all patients. All patients were followed-up for from 5 to 26 months (means 13.5 months). There was no important vascular and nerve injury and no wound infection. Neutral symptoms was improved and all patient got successful fusion. The "window" surgical exposure surgical technique of the upper cervical anterior retropharyngeal approach is a favorable strategy. This approach strategy can be performed with full exposure for C1-C3 anterior anatomical structure, and can get minimally invasive surgery results and few and far between wound complication, that is safe if corresponding experience is achieved.

  1. Temporary percutaneous T-fastener gastropexy and continuous decompressive gastrostomy in dogs with experimentally induced gastric dilatation. (United States)

    Fox-Alvarez, W Alexander; Case, J Brad; Cooke, Kirsten L; Garcia-Pereira, Fernando L; Buckley, Gareth J; Monnet, Eric; Toskich, Beau B


    OBJECTIVE To evaluate a percutaneous, continuous gastric decompression technique for dogs involving a temporary T-fastener gastropexy and self-retaining decompression catheter. ANIMALS 6 healthy male large-breed dogs. PROCEDURES Dogs were anesthetized and positioned in dorsal recumbency with slight left-lateral obliquity. The gastric lumen was insufflated endoscopically until tympany was evident. Three T-fasteners were placed percutaneously into the gastric lumen via the right lateral aspect of the abdomen, caudal to the 13th rib and lateral to the rectus abdominis muscle. Through the center of the T-fasteners, a 5F locking pigtail catheter was inserted into the gastric lumen and attached to a device measuring gas outflow and intragastric pressure. The stomach was insufflated to 23 mm Hg, air was allowed to passively drain from the catheter until intraluminal pressure reached 5 mm Hg for 3 cycles, and the catheter was removed. Dogs were hospitalized and monitored for 72 hours. RESULTS Mean ± SD catheter placement time was 3.3 ± 0.5 minutes. Mean intervals from catheter placement to a ≥ 50% decrease in intragastric pressure and to ≤ 6 mm Hg were 2.1 ± 1.3 minutes and 8.4 ± 5.1 minutes, respectively. After catheter removal, no gas or fluid leakage at the catheter site was visible laparoscopically or endoscopically. All dogs were clinically normal 72 hours after surgery. CONCLUSIONS AND CLINICAL RELEVANCE The described technique was performed rapidly and provided continuous gastric decompression with no evidence of postoperative leakage in healthy dogs. Investigation is warranted to evaluate its effectiveness in dogs with gastric dilatation-volvulus.

  2. Cleaning and decompression of inferior alveolar canal to treat dysesthesia and paresthesia following endodontic treatment of a third molar

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    Rudy Scala


    Full Text Available Endodontic overfilling involving the mandibular canal may cause an injury of the inferior alveolar nerve (IAN. We report a case of disabling dysesthesia and paresthesia of a 70-year-old man after endodontic treatment of his mandibular left third molar that caused leakage of root canal filling material into the mandibular canal. After radiographic evaluation, extraction of the third molar and distal osteotomy, a surgical exploration was performed and followed by removal of the material and decompression of the IAN. The patient reported an improvement in sensation and immediate disappearance of dysesthesia already from the first postoperative day.

  3. [Effectiveness of multiple small-diameter drilling decompression combined with hip arthroscopy for early osteonecrosis of the femoral head]. (United States)

    Li, Ji; Li, Zhongli; Su, Xiangzheng; Liu, Chunhui; Zhang, Hao; Wang, Ketao


    To evaluate the effectiveness of multiple small-diameter drilling decompression combined with hip arthroscopy for early oeteonecrosis of the femoral head (ONFH). Between March 2010 and December 2013, 91 patients with early ONFH were treated with the operation of multiple small-diameter drilling decompression combined with hip arthroscopy in 39 cases (53 hips, group A) or with drilling decompression alone in 52 cases (74 hips, group B). The patients in 2 groups had obvious hip pain and limited motion before operation. There was no significant difference in gender, age, etiology, effected side, stage of osteonecrosis, and preoperative Harris score between 2 groups ( P >0.05). All operations succeeded and all incisions healed by first intention. The operation time was significantly longer in group A [(73.3±10.6) minutes] than in group B [(41.5±7.2) minutes] ( t =8.726, P =0.000). Temporary of sciatic nerve apraxia after operation occurred in 2 patients of group A, and no complication occurred in other patients. Patients were followed up 24-52 months (mean, 39.3 months) in group A and 24-48 months (mean, 34.6 months) in group B. At last follow-up, the Harris scores were 83.34±8.76 in group A and 76.61±9.22 in group B, showing significant differences when compared between 2 groups ( t =-4.247, P =0.029) and when compared with preoperative values in 2 groups ( t =-10.327, P =0.001; t =-8.216, P =0.008). X-ray films showed that the collapse of the femoral head was observed in 6 hips (1 hip at stage Ⅰand 5 hips at stage Ⅱ) in group A, and in 16 hips (4 hips at stageⅠand 12 hips at stage Ⅱ) in group B; and hip arthroplasty was performed. The total effective rates were 88.68% (47/53) in group A and 78.38% (58/74) in group B, respectively; showing significant difference between 2 groups ( χ 2 =5.241, P =0.041). Multiple small-diameter drilling decompression combined with hip arthroscopy is effective in pain relief, improvement of hip function, slowing-down the

  4. Utilization of steam- and explosion-decompressed aspen wood by some anaerobes. [Acetivibrio cellulolyticus, Clostridium saccharolyticum, Zymomonas anaerobia

    Energy Technology Data Exchange (ETDEWEB)

    Khan, A W; Asther, M; Giuliano, C


    Tests made to study the suitability of using steam- and explosion-decompressed aspen wood as substrate in anaerobic fermentations indicated that after washing with dilute NaOH it becomes over 80% accessible to both mesophilic and thermophilic cellulolytic anaerobes and cellulases, compared with delignified, ball-milled pulp. After washing, this material was also found to be suitable for the single-step conversion of cellulose to ethanol using cocultures consisting of cellylolytic and ethanol-producing saccharolytic anaerobes; and without and after washing by the use of cellulolytic enzymes and ethanologenic anaerobes. 16 references, 3 tables.

  5. Cleaning and decompression of inferior alveolar canal to treat dysesthesia and paresthesia following endodontic treatment of a third molar. (United States)

    Scala, Rudy; Cucchi, Alessandro; Cappellina, Luca; Ghensi, Paolo


    Endodontic overfilling involving the mandibular canal may cause an injury of the inferior alveolar nerve (IAN). We report a case of disabling dysesthesia and paresthesia of a 70-year-old man after endodontic treatment of his mandibular left third molar that caused leakage of root canal filling material into the mandibular canal. After radiographic evaluation, extraction of the third molar and distal osteotomy, a surgical exploration was performed and followed by removal of the material and decompression of the IAN. The patient reported an improvement in sensation and immediate disappearance of dysesthesia already from the first postoperative day.

  6. The "Skull Flap" a new conceived device for decompressive craniectomy experimental study on dogs to evaluate the safety and efficacy in reducing intracranial pressure and subsequent impact on brain perfusion. (United States)

    Salvatore, Chibbaro; Fabrice, Vallee; Marco, Marsella; Leonardo, Tigan; Thomas, Lilin; Benoit, Lecuelle; Bernard, George; Pierre, Kehrli; Eric, Vicaut; Paolo, Diemidio


    Decompressive craniectomy (DC) is a procedure performed increasingly often in current neurosurgical practice. Significant perioperative morbidity may be associated to this procedure because of the large skull defect; also, later closure of the skull defect (cranioplasty) may be associated to post-operative morbidity as much as any other reconstructive operation. The authors present a newly conceived/developed device: The "Skull Flap" (SF). This system, placed at the time of the craniectomy, offers the possibility to provide cranial reconstruction sparing patients a second operation. In other words, DC and cranioplasty essentially take place at the same time and in addition, patients retain their own bone flap. The current study conducted on animal models, represents the logical continuation of a prior recent study, realized on cadaver specimens, to assess the efficacy and safety of this recently developed device. This is an experimental pilot study on dogs to assess both safety and efficacy of the SF device. Two groups of experimental raised intracranial pressure animal models underwent DC; in the first group of dogs, the bone flap was left in raised position above the skull defect using the SF device; on the second group the flap was discarded. All dogs underwent transcranial Doppler (TCD) to assess brain perfusion. Head computed tomography (CT) scan to determine flap position was also obtained in the group in which the SF device was placed. SF has proved to be a strong fixation device that allows satisfactory brain decompression by keeping the bone flap elevated from the swollen brain; later on, the SF allows cranial reconstruction in a simple way without requiring a second staged operation. In addition, it is relevant to note that brain perfusion was measured and found to be better in the group receiving the SF (while the flap being in a raised as well as in its natural position) comparing to the other group. The SF device has proved to be very easy to place

  7. The "Skull Flap" a new conceived device for decompressive craniectomy experimental study on dogs to evaluate the safety and efficacy in reducing intracranial pressure and subsequent impact on brain perfusion

    Directory of Open Access Journals (Sweden)

    Chibbaro Salvatore


    Full Text Available Background: Decompressive craniectomy (DC is a procedure performed increasingly often in current neurosurgical practice. Significant perioperative morbidity may be associated to this procedure because of the large skull defect; also, later closure of the skull defect (cranioplasty may be associated to post-operative morbidity as much as any other reconstructive operation. The authors present a newly conceived/developed device: The "Skull Flap" (SF. This system, placed at the time of the craniectomy, offers the possibility to provide cranial reconstruction sparing patients a second operation. In other words, DC and cranioplasty essentially take place at the same time and in addition, patients retain their own bone flap. The current study conducted on animal models, represents the logical continuation of a prior recent study, realized on cadaver specimens, to assess the efficacy and safety of this recently developed device. Materials and Methods: This is an experimental pilot study on dogs to assess both safety and efficacy of the SF device. Two groups of experimental raised intracranial pressure animal models underwent DC; in the first group of dogs, the bone flap was left in raised position above the skull defect using the SF device; on the second group the flap was discarded. All dogs underwent transcranial Doppler (TCD to assess brain perfusion. Head computed tomography (CT scan to determine flap position was also obtained in the group in which the SF device was placed. Results: SF has proved to be a strong fixation device that allows satisfactory brain decompression by keeping the bone flap elevated from the swollen brain; later on, the SF allows cranial reconstruction in a simple way without requiring a second staged operation. In addition, it is relevant to note that brain perfusion was measured and found to be better in the group receiving the SF (while the flap being in a raised as well as in its natural position comparing to the other

  8. Intraoperative 3-dimensional navigation and ultrasonography during posterior decompression with instrumented fusion for ossification of the posterior longitudinal ligament in the thoracic spine. (United States)

    Tian, Wei; Weng, Chong; Liu, Bo; Li, Qin; Sun, Yu-Qing; Yuan, Qiang; Zhang, Bo; Wang, Yong-Qing; He, Da


    A retrospective clinical study was conducted. The purpose of this study was to describe the clinical outcomes of intraoperative 3D navigation (ITN) and ultrasonography during posterior decompression and instrumented fusion for thoracic myelopathy due to ossification of the posterior longitudinal ligament (OPLL). The symptoms caused by thoracic-ossification of the posterior longitudinal ligament (T-OPLL) are usually progressive and do not respond to conservative treatment-surgical intervention is the only effective treatment option. Various methods have been described for the treatment of symptomatic T-OPLL, all of which have limitations. The study included 18 patients with T-OPLL who underwent posterior decompression with instrumented fusion from 2006 to 2011. A staged operative procedure was used. First, pedicle screws were placed with ITN and a wide laminectomy was performed with resection of ossification of the ligamentum flavum (if present). With insufficient decompression on intraoperative ultrasonography, additional circumferential decompression was performed through a transpedicular approach. ITN-guided OPLL resection was performed using a burr attached to a navigational tracker. In all cases, posterior instrumented fusion was performed in situ. The outcomes were evaluated with the modified Japanese Orthopaedic Association scores and recovery rates. Intraoperative ultrasonography showed that posterior laminectomy was sufficient in 6 patients; the remaining 12 were treated with additional circumferential decompression. The follow-up period ranged from 1 to 6 years (mean period, 2.8 y). Postoperative transient neurological deterioration occurred in 1 patient, and cerebrospinal fluid leakage occurred in 4 patients. All patients showed neurological recovery with a mean Japanese Orthopaedic Association score that improved from 5.5 points preoperatively to 8.5 points at the final follow-up and a mean recovery rate of 54.5%. Intraoperative ultrasonography and ITN

  9. The effect of rapid and sustained decompression on barotrauma in juvenile brook lamprey and Pacific lamprey: implications for passage at hydroelectric facilities

    Energy Technology Data Exchange (ETDEWEB)

    Colotelo, Alison HA; Pflugrath, Brett D.; Brown, Richard S.; Brauner, Colin J.; Mueller, Robert P.; Carlson, Thomas J.; Deng, Zhiqun; Ahmann, Martin L.; Trumbo, Bradly A.


    Fish passing downstream through hydroelectric facilities may pass through hydroturbines where they experience a rapid decrease in barometric pressure as they pass by turbine blades, which can lead to barotraumas including swim bladder rupture, exopthalmia, emboli, and hemorrhaging. In juvenile Chinook salmon, the main mechanism for injury is thought to be expansion of existing gases (particularly those present in the swim bladder) and the rupture of the swim bladder ultimately leading to exopthalmia, emboli and hemorrhaging. In fish that lack a swim bladder, such as lamprey, the rate and severity of barotraumas due to rapid decompression may be reduced however; this has yet to be extensively studied. Another mechanism for barotrauma can be gases coming out of solution and the rate of this occurrence may vary among species. In this study, juvenile brook and Pacific lamprey acclimated to 146.2 kPa (equivalent to a depth of 4.6 m) were subjected to rapid (<1 sec; brook lamprey only) or sustained decompression (17 minutes) to a very low pressure (13.8 kPa) using a protocol previously applied to juvenile Chinook salmon. No mortality or evidence of barotraumas, as indicated by the presence of hemorrhages, emboli or exopthalmia, were observed during rapid or sustained decompression, nor following recovery for up to 120 h following sustained decompression. In contrast, mortality or injury would be expected for 97.5% of juvenile Chinook salmon exposed to a similar rapid decompression to these very low pressures. Additionally, juvenile Chinook salmon experiencing sustained decompression died within 7 minutes, accompanied by emboli in the fins and gills and hemorrhaging in the tissues. Thus, juvenile lamprey may not be susceptible to barotraumas associated with hydroturbine passage to the same degree as juvenile salmonids, and management of these species should be tailored to their specific morphological and physiological characteristics.

  10. Surgical outcome of posterior decompression, posterolateral fusion and stabilization by pedicle screw and rod in thoracolumbar tuberculosis

    Directory of Open Access Journals (Sweden)

    Md. Anowarul Islam


    Full Text Available Spinal tuberculosis causes severe complications like neurological and spinal deformity which may lead to respiratory distress, costo-pelvic impingement, paraplegia and consequent reduction in the quality and longevity of life. The aim of the present treatment is to avoid the consequence of neural complications and gain near-normal spine. Mechanical factor causes pathological fracture or dislocation of an affected vertebral body. Surgical decompression ensues further instability. Reconstruction of spinal column by pedicle screw and rod provide stability and prevents secondary neural damage and deformity thereby helps in early mobilization. Prospective study was done to evaluate the results in 20 cases of spinal tuberculosis in thoracolumbar region associated with neurological deficit. We operated our cases (12 males and 8 females by posterolateral decompression, fusion and stabilization by pedicle screw and rod along with antitubercular drug treatment. All patients were with neurological deficit, single level involvement and 10 to 30 degree of mild kyphosis. After surgery, kyphosis improved from 20.7 ± 5.5 degrees to 12.5 ± 3.9 degree. Bony fusion was in 65.0% cases. Neurological improvement and pain subsided in all the patients.

  11. Subdural Fluid Collection and Hydrocephalus After Foramen Magnum Decompression for Chiari Malformation Type I: Management Algorithm of a Rare Complication. (United States)

    Rossini, Zefferino; Milani, Davide; Costa, Francesco; Castellani, Carlotta; Lasio, Giovanni; Fornari, Maurizio


    Chiari malformation type I is a hindbrain abnormality characterized by descent of the cerebellar tonsils beneath the foramen magnum, frequently associated with symptoms or brainstem compression, impaired cerebrospinal fluid circulation, and syringomyelia. Foramen magnum decompression represents the most common way of treatment. Rarely, subdural fluid collection and hydrocephalus represent postoperative adverse events. The treatment of this complication is still debated, and physicians are sometimes uncertain when to perform diversion surgery and when to perform more conservative management. We report an unusual occurrence of subdural fluid collection and hydrocephalus that developed in a 23-year-old patient after foramen magnum decompression for Chiari malformation type I. Following a management protocol, based on a step-by-step approach, from conservative therapy to diversion surgery, the patient was managed with urgent external ventricular drainage, and then with conservative management and wound revision. Because of the rarity of this adverse event, previous case reports differ about the form of treatment. In future cases, finding clinical and radiologic features to identify risk factors that are useful in predicting if the patient will benefit from conservative management or will need to undergo diversion surgery is only possible if a uniform form of treatment is used. Therefore, we believe that a management algorithm based on a step-by-step approach will reduce the use of invasive therapies and help to create a standard of care. Copyright © 2017 Elsevier Inc. All rights reserved.

  12. Unusual Ventilatory Response to Exercise in Patient with Arnold-Chiari Type 1 Malformation after Posterior Fossa Decompression

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    Keely Smith


    Full Text Available We present a case of a 17-year-old Hispanic male with Arnold-Chiari Type 1 [AC-Type 1] with syringomyelia, status post decompression, who complains of exercise intolerance, headaches, and fatigue with exertion. The patient was found to have diurnal hypercapnia and nocturnal alveolar hypoventilation. Cardiopulmonary testing revealed blunting of the ventilatory response to the rise in carbon dioxide (CO2 resulting in failure of the parallel correlation between increased CO2 levels and ventilation; the expected vertical relationship between PETCO2 and minute ventilation during exercise was replaced with an almost horizontal relationship. No new pathology of the brainstem was discovered by MRI or neurological evaluation to explain this phenomenon. The patient was placed on continuous noninvasive open ventilation (NIOV during the day and CPAP at night for a period of 6 months. His pCO2 level decreased to normal limits and his symptoms improved; specifically, he experienced less headaches and fatigue during exercise. In this report, we describe the abnormal response to exercise that patients with AC-Type 1 could potentially experience, even after decompression, characterized by the impairment of ventilator response to hypercapnia during exertion, reflecting a complete loss of chemical influence on breathing with no evidence of abnormality in the corticospinal pathway.

  13. The clinical efficacy and prognosis of hemisphere skull bone flap decompression and mild hypothermia treatment for severe craniocerebral trauma

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    YANG Hua-tang


    Full Text Available In this study, 1626 patients with severe craniocerebral trauma were assessed by Glasgow Coma Scale (GCS, 886 patients of 3-5 score and 740 of 6-8 score. Patients were divided into 2 groups. Ninety hundred and eleven patients (496 of 3-5 score and 415 of 6-8 score underwent hemisphere calvarial bone flap decompression with auxiliary mild hypothermia (experiment group, and 715 patients (390 of 3-5 score and 325 of 6-8 score underwent traditional frontal, temporal, parietal large traumatic craniotomy (control group. After operation the treatment of 2 groups was basically the same. Compared with control group, the intracranial pressure of experiment group on the 1st, 3rd, 5th and 7th days after surgery decreased significantly (P < 0.05, for all; the consciousness recovery time was significantly shorter (P < 0.05, for all; the prognosis after 3 months was better (P < 0.05, for all. Hemisphere calvarial bone flap decompression with auxiliary mild hypothermia treatment could significantly reduce the morbidity and mortality, and improve the quality of life and prognosis of patients with severe craniocerebral trauma.

  14. Correlation of MR tomographic findings and microvascular decompression treatment of the neurovascular compressions of the cranial nerves

    International Nuclear Information System (INIS)

    Liu Zengsheng; Chen Xiangmin; Sun Yiyan; Fang Ming; Wang Ping; Guan Yong; Sun Miao


    Objective: To explore the correlation of the operation effects of the miorovascular decompression (MVD) and the findings on magnetic resonance tomographie angiography (MRTA) in patients of neurovascular compression of the cranial nerves. Methods: Two hundred and twenty three patients treated with the microvascular decompression were analyzed retrospectively. They were grouped and graded according to the vessel compression on the cranial nerves. The compression were grouped as none, moderate and severe, and the operation effects were graded as I (complete relief), II (partial relief) and III ( no relief). The operation effects grades were correlated according to the compression groups by Kruskal-Wallis test and the operation effects between each two of the groups were compared using Nemenyi test. P 2 =16.84 and P<0.05. The mean rank of the non-compression, the moderate and the severe group was 134.21,102.37 and 110.4, respectively. The difference of the mean ranks between the non-compression group and the moderate group was 31.84, and between the non-compression and the severe group was 24.17, respectively, where P<0.05 both. Conclusions: There was close relationship between the findings on magnetic resonance tomographic angiography and the operation effects of the MVD. The operation effects of patients with moderate and severe vessel compression were much better than the non-compression group. MRTA is helpful for MVD surgical indication and its prognosis. (authors)

  15. Islamic vs. conventional banks : Business models, efficiency and stability

    NARCIS (Netherlands)

    Beck, T.H.L.; Demirgüc-Kunt, A.; Merrouche, O.


    How different are Islamic banks from conventional banks? Does the recent crisis justify a closer look at the Sharia-compliant business model for banking? When comparing conventional and Islamic banks, controlling for time-variant country-fixed effects, we find few significant differences in business

  16. Neurorestoratology evidence in an animal model with cervical spondylotic myelopathy

    Directory of Open Access Journals (Sweden)

    Li X


    Full Text Available Xiang Li,1,2 Guangsheng Li,1,3 Keith Dip-Kei Luk,1 Yong Hu1–3 1Department of Orthopaedics and Traumatology, The University of Hong Kong, Pokfulam, Hong Kong, 2Shenzhen Key Laboratory for Innovative Technology in Orthopaedic Trauma, The University of Hong Kong-Shenzhen Hospital, Shenzhen, 3Spinal Division, Department of Orthopaedics, Affiliated Hospital of Guangdong Medical University, Guangdong, People’s Republic of China Background: Cervical spondylotic myelopathy (CSM is a chronic compression injury of the spinal cord, with potentially reversible conditions after surgical decompression, and a unique model of incomplete spinal cord injury. Several animal studies showed pathological changes of demyelination, axon loss and neuron apoptosis in rats with chronic spinal cord compression. However, there is a limited understanding of the neurological change in the spinal cord after surgical decompression. The aim of this study was to validate the neurorestoratology of myelopathic lesions in the spinal cord in a rat model. Materials and methods: A total of 16 adult Sprague-Dawley rats were divided into four groups: sham control (group 1; CSM model with 4-week chronic compression (group 2, 2 weeks (group 3 and 4 weeks (group 4 after surgical decompression of CSM model. The compression and decompression were verified by magnetic resonance imaging (MRI test. Neurological function was evaluated by Basso, Beattie, and Bresnahan (BBB locomotor rating scale, ladder rung walking test and somatosensory-evoked potentials (SEPs. Neuropathological change was evaluated by histological examinations. Results: MRI confirmed the compression of the cervical spinal cord as well as the reshaping of cord morphology after decompression. After decompression, significant changes of neurological function were observed in BBB scores (p < 0.01, F = 10.52, ladder rung walking test (p < 0.05, F = 14.21 and latencies (p < 0.05, F = 5.76 and amplitudes (p < 0.05, F = 3.8 of

  17. Decompressive L5 Transverse Processectomy for Bertolotti's Syndrome: A Preliminary Study. (United States)

    Ju, Chang Il; Kim, Seok Won; Kim, Jong Gyue; Lee, Seung Myung; Shin, Ho; Lee, Hyeun Young


    postoperative VAS was 2.86 ± 1.67 (group A: 3.82 ± 1.59, group B: 2.05 ± 1.00). According to Macnab's criteria, 12 patients showed excellent results (group A: 3, group B: 9), 41 patients showed good results (group A: 11, group B: 30), 6 patients showed fair results (group A: 5, group B: 1), and 2 patients showed poor results (group A: 2, group B: 0). Thus, satisfactory results were achieved in 86.89% of the cases. In patients with Bertolotti's syndrome, pseudoarticulation as well as L4 nerve root compression can be the source of buttock pain and lower extremity pain. Bisectional cutting of the L5 transverse process and decompression of the L4 nerve root could be an optimal treatment for Bertolotti's syndrome, and it may be easily approached by the paraspinal approach. This is a retrospective study and only offers one-year follow-up data for patients with Bertolotti's syndrome who have undergone L5 transverse process resection.Key words: Bertolotti's syndrome, pseudoarticulation, L5 transverse processectomy, paraspinal approach.

  18. Simulación de sistemas eléctricos con cargas no lineales y variantes en el tiempo Simulation of electric systems with non-linear and time-variant loads

    Directory of Open Access Journals (Sweden)

    William Carvajal Carreño


    of them and it permits to analyze linear and non linear systems in the time domain, linear systems in the frequency domain and mixed systems using the proposed hybrid method. The tool is intended to be a versatile and comprehensive computation instrument. Besides, it can be used in a straightforward way to analyze harmonic propagation in electrical networks. Examples from the literature used in electrical circuits, power systems, and power electronics courses are shown. Likewise, in order to analyze non-linear or time-varying loads, test systems were created as a benchmark for testing simulators of harmonics in electrical systems. Simulation results are analyzed and observations about the convergence features and algorithm stability of the proposed method are given. Due to the complexity and computational burden of hybrid analysis, we have selected element models, system models and suitable algorithms to guarantee that the solution is reasonable in terms of simulation time and computer resources.

  19. Effects of decompressive cervical surgery on blood pressure in cervical spondylosis patients with hypertension: a time series cohort study. (United States)

    Liu, Hong; Wang, Hai-Bo; Wu, Lin; Wang, Shi-Jun; Yang, Ze-Chuan; Ma, Run-Yi; Reilly, Kathleen H; Yan, Xiao-Yan; Ji, Ping; Wu, Yang-feng


    Patients with cervical spondylosis myelopathy (CSM) and complicated with hypertension are often experiencing a blood pressure decrease after taking cervical decompressive surgery in clinical observations, but how this blood pressure reduction is associated with the surgery, which cut cervical sympathetic nervous, has never been rigorously assessed. Thus, the purpose of this study is to investigate the effect of cervical decompressive surgery on blood pressure among CSM patients with hypertension. The study will be a time series cohort study. Fifty eligible patients will be selected consecutively from the Peking University First Hospital. Two 24-h ambulatory blood pressure measurement (ABPM) will be taken before the surgery, apart by at least 3 days. The patients will be followed up for another two ABPMs at 1 and 3 months after the surgery. We will recruit subjects with cervical spondylosis myelopathy meeting operation indications and scheduled for receiving cervical decompressive surgery, aged 18-84 years, have a history of hypertension or office systolic blood pressure ≥140 mmHg on initial screening, and willing to participate in the study and provide informed consent. Exclusion criteria includes a history of known secondary hypertension, visual analogue scale (VAS) score ≥4, and unable to comply with study due to severe psychosis. The change in systolic ABPs over the four times will be analyzed to observe the overall pattern of the blood pressure change in relation to the surgery, but the primary analysis will be the comparison of systolic ABP between the 2(nd) and 3(rd), 4(th) measurements (before and after the surgery). We will also calculate the regression-to-the-mean adjusted changes in systolic ABP as sensitivity analysis. Secondary endpoints are the changes in 24 h ABPM diastolic blood pressure, blood pressure control status, the use and dose adjustment of antihypertensive medication, and the incidence of operative complications. Primary outcome

  20. Acute Hemorrhagic Encephalitis Responding to Combined Decompressive Craniectomy, Intravenous Immunoglobulin, and Corticosteroid Therapies: Association with Novel RANBP2 Variant

    Directory of Open Access Journals (Sweden)

    Abdulla Alawadhi


    Full Text Available BackgroundAcute hemorrhagic encephalomyelitis (AHEM is considered as a rare form of acute disseminated encephalomyelitis characterized by fulminant encephalopathy with hemorrhagic necrosis and most often fatal outcome.ObjectiveTo report the association with Ran Binding Protein (RANBP2 gene variant and the response to decompressive craniectomy and high-dose intravenous methylprednisolone (IVMP in life-threatening AHEM.DesignSingle case study.Case reportA 6-year-old girl known to have sickle cell disease (SCD presented an acquired demyelinating syndrome (ADS with diplopia due to sudden unilateral fourth nerve palsy. She received five pulses of IVMP (30 mg/kg/day. Two weeks after steroid weaning, she developed right hemiplegia and coma. Brain magnetic resonance imaging showed a left frontal necrotico-hemorrhagic lesion and new multifocal areas of demyelination. She underwent decompressive craniotomy and evacuation of an ongoing left frontoparietal hemorrhage. Comprehensive investigations ruled out vascular and infectious process. The neurological deterioration stopped concomitantly with combined neurosurgical drainage of the hematoma, decompressive craniotomy, IVMP, and intravenous immunoglobulins (IVIG. She developed during the following months Crohn disease and sclerosing cholangitis. After 2-year follow-up, there was no new neurological manifestation. The patient still suffered right hemiplegia and aphasia, but was able to walk. Cognitive/behavioral abilities significantly recovered. A heterozygous novel rare missense variant (c.4993A>G, p.Lys1665Glu was identified in RANBP2, a gene associated with acute necrotizing encephalopathy. RANBP2 is a protein playing an important role in the energy homeostasis of neuronal cells.ConclusionIn any ADS occurring in the context of SCD and/or autoimmune condition, we recommend to slowly wean steroids and to closely monitor the patient after weaning to quickly treat any recurrence of neurological symptom

  1. Microvascular decompression of the cochleovestibular nerve for treatment of tinnitus and vertigo : a systematic review and meta-analysis of individual patient data

    NARCIS (Netherlands)

    van den Berge, Minke J C; van Dijk, J. Marc C.; Posthumus, Iris A; Smidt, Nynke; van Dijk, Pim; Free, Rolien H

    OBJECTIVE Microvascular decompression (MVD) is regarded as a valid treatment modality in neurovascular conflicts (NVCs) causing, for example, trigeminal neuralgia and hemifacial spasms. An NVC of the cochleovestibular nerve might cause tinnitus and/or vertigo; however, general acceptance of MVD for

  2. The relationship between cervical lordosis and Nurick scores in patients undergoing circumferential vs. posterior alone cervical decompression, instrumentation and fusion for treatment of cervical spondylotic myelopathy. (United States)

    Patel, Shalin; Glivar, Phillip; Asgarzadie, Farbod; Cheng, David Juma Wayne; Danisa, Olumide


    The loss of regional cervical sagittal alignment and the progressive development of cervical kyphosis is a factor in the advancement of myelopathy. Adequate decompression of the spinal canal along with reestablishment of cervical lordosis are desired objective with regard to the surgical treatment of patients with cervical spondylotic myelopathy. A retrospective chart review was conducted in which patients who underwent either a combined anterior/posterior instrumentation and decompression or a posterior alone instrumentation and decompression for the treatment of CSM at our institution were identified. Any patient undergoing operative intervention for trauma, infection or tumors were excluded. Similarly, patients undergoing posterior instrumentation with constructs extending beyond the level of C2-C7 were similarly excluded from this study. A total of 67 patients met the inclusion criteria for this study. A total of 32 patients underwent posterior alone surgery and the remaining 35 underwent combined anterior/posterior procedure. Radiographic evaluation of patient's preoperative and postoperative cervical lordosis as measured by the C2-C7 Cobb angle was performed. Each patient's preoperative and postoperative functional disability as enumerated by the Nurick score was also recorded. Statistical analysis was conducted to determine if there was a significant relationship between improvement in cervical lordosis and improvement in patient's clinical outcomes as enumerated by the Nurick Score in patients undergoing posterior alone versus combined anterior/posterior decompression, instrumentation and fusion of the cervical spine. Copyright © 2017 Elsevier Ltd. All rights reserved.

  3. Surgical decompression for space-occupying cerebral infarction (the Hemicraniectomy After Middle Cerebral Artery infarction with Life-threatening Edema Trial [HAMLET]): a multicentre, open, randomised trial

    NARCIS (Netherlands)

    Hofmeijer, Jeannette; Kappelle, L. Jaap; Algra, Ale; Amelink, G. Johan; van Gijn, Jan; van der Worp, H. Bart; Algra, A.; Amelink, G. J.; van Gijn, J.; Hofmeijer, J.; Kappelle, L. J.; Macleod, M. R.; van der Worp, H. B.; de Bruijn, S. F. T. M.; Luijckx, G. J.; van Oostenbrugge, R.; Stam, J.; Boiten, J.; van der Graaf, Y.; Koudstaal, P. J.; Maas, A. I. R.; van Dijk, G. W.; Hacke, W.; Kalkman, C. J.; Tulleken, C. A. F.; Wijman, C. A. C.; van Buuren, M.


    BACKGROUND: Patients with space-occupying hemispheric infarctions have a poor prognosis, with case fatality rates of up to 80%. In a pooled analysis of randomised trials, surgical decompression within 48 h of stroke onset reduced case fatality and improved functional outcome; however, the effect of

  4. Clinical outcomes of radiotherapy as initial local therapy for Graves’ ophthalmopathy and predictors of the need for post-radiotherapy decompressive surgery

    International Nuclear Information System (INIS)

    Prabhu, Roshan S; Liebman, Lang; Wojno, Ted; Hayek, Brent; Hall, William A; Crocker, Ian


    The optimal initial local treatment for patients with Graves’ ophthalmopathy (GO) is not fully characterized. The purpose of this retrospective study is to describe the clinical outcomes of RT as initial local therapy for GO and define predictors of the need for post-RT salvage bony decompressive surgery. 91 patients with active GO and without prior surgery were treated with RT as initial local therapy between 01/1999 and 12/2010, with a median follow-up period of 18.3 months (range 3.7 - 142 months). RT dose was 24 Gy in 12 fractions. 44 patients (48.4%) had prior use of steroids, with 31 (34.1%) being on steroids at the initiation of RT. The most common presenting symptoms were diplopia (79%), proptosis (71%) and soft tissue signs (62%). 84 patients (92.3%) experienced stabilization or improvement of GO symptoms. 58 patients (64%) experienced improvement in their symptoms. 19 patients (20.9%) underwent salvage post-RT bony decompressive surgery. Smoking status and total symptom score at 4 months were independent predictors of post-RT bony decompression with odds ratios of 3.23 (95% CI 1.03 – 10.2) and 1.59 (95% CI 1.06 – 2.4), respectively. Persistent objective vision loss at 4 months post-RT was the most important symptom type in predicting salvage decompression. Chronic dry eye occurred in 9 patients (9.9%) and cataracts developed in 4 patients (4.4%). RT is effective and well tolerated as initial local therapy for active GO, with only 21% of patients requiring decompressive surgery post RT. Most patients experience stabilization or improvement of GO symptoms, but moderate to significant response occurs in the minority of patients. Smoking status and total symptom severity at 4 months, primarily persistent objective vision loss, are the primary determinants of the need for post-RT salvage bony decompression. Patients who smoke or present with predominantly vision loss symptoms should be advised as to their lower likelihood of symptomatic response to RT

  5. Microneurolysis and decompression of long thoracic nerve injury are effective in reversing scapular winging: Long-term results in 50 cases

    Directory of Open Access Journals (Sweden)

    Lyons Andrew B


    Full Text Available Abstract Background Long thoracic nerve injury leading to scapular winging is common, often caused by closed trauma through compression, stretching, traction, direct extrinsic force, penetrating injury, or neuritides such as Parsonage-Turner syndrome. We undertook the largest series of long thoracic nerve decompression and neurolysis yet reported to demonstrate the usefulness of long thoracic nerve decompression. Methods Winging was bilateral in 3 of the 47 patients (26 male, 21 female, yielding a total of 50 procedures. The mean age of the patients was 33.4 years, ranging from 24–57. Causation included heavy weight-lifting (31 patients, repetitive throwing (5 patients, deep massage (2 patients, repetitive overhead movement (1 patient, direct trauma (1 patient, motor bike accident (1 patient, and idiopathic causes (9 patients. Decompression and microneurolysis of the long thoracic nerve were performed in the supraclavicular space. Follow-up (average of 25.7 months consisted of physical examination and phone conversations. The degree of winging was measured by the operating surgeon (RKN. Patients also answered questions covering 11 quality-of-life facets spanning four domains of the World Health Organization Quality of Life questionnaire. Results Thoracic nerve decompression and neurolysis improved scapular winging in 49 (98% of the 50 cases, producing "good" or "excellent" results in 46 cases (92%. At least some improvement occurred in 98% of cases that were less than 10 years old. Pain reduction through surgery was good or excellent in 43 (86% cases. Shoulder instability affected 21 patients preoperatively and persisted in 5 of these patients after surgery, even in the 5 patients with persistent instability who experienced some relief from the winging itself. Conclusion Surgical decompression and neurolysis of the long thoracic nerve significantly improve scapular winging in appropriate patients, for whom these techniques should be considered

  6. A Good Short-term Outcome in Delayed Decompression of Cauda Equina Syndrome in Klebsiella pneumoniae Spinal Epidural Abscess: A Case Report

    Directory of Open Access Journals (Sweden)

    Hanifah J


    Full Text Available Spinal epidural abscess is a severe, generally pyogenic, infection of the epidural space of spinal cord or cauda equina. The swelling caused by the abscess leads to compression or vascular disruption of neurological structures that requires urgent surgical decompression to avoid significant permanent disability. We share a rare case of Klebsiella pneumoniae spinal epidural abscess secondary to haematogenous spread of previous lung infection that presented late at our centre with cauda equina syndrome that showed good short-term outcome in delayed decompression. A 50-year old female presented with one-week history of persistent low back pain with progressively worsening bilateral lower limb weakness for seven days and urinary retention associated with saddle anesthesia of 2-day duration. Magnetic resonance imaging with contrast of the lumbo-sacral region showed an intramuscular collection of abscess at left gluteus maximus and left multifidus muscle with a L3-L5 posteriorly placed extradural lesion enhancing peripherally on contrast, suggestive of epidural abscess that compressed the cauda equina. The pus was drained using the posterior lumbar approach. Tissue and pus culture revealed Klebsiella pneumoniae, suggestive of bacterial infection. The patient made immediate improvement of muscle power over bilateral lower limbs postoperative followed by ability to control micturition and defecation in the 4th post-operative day. A good short-term outcome in delayed decompression of cauda equine syndrome is extremely rare. Aggressive surgical decompression combined with antibiotic therapy led to good short-term outcome in this patient despite delayed decompression of more than 48 hours.

  7. Delayed ischemic cecal perforation despite optimal decompression after placement of a self-expanding metal stent: report of a case

    DEFF Research Database (Denmark)

    Knop, Filip Krag; Pilsgaard, Bo; Meisner, Søren


    Endoscopic deployment of self-expanding metal stents offers an alternative to surgical intervention in rectocolonic obstructions. Reported clinical failures in the literature are all related to the site of stent placement. We report a case of serious intra-abdominal disease after technically...... and clinically successful stent deployment: a potentially dangerous situation of which the surgeon should be aware. A previously healthy 72-year-old female was referred to our department with symptoms of an obstructing colorectal tumor. Successful stent placement resulted in resolution of the obstructive......, probably caused by ischemic conditions developed before stent-decompression of the colon was revealed during the operation. The patient died in the postoperative course. We discuss the observation of patients treated with self-expanding metal stents based on the selection-strategy used to allocate patients...

  8. Microvascular decompression surgery for vertebral artery compression of the medulla oblongata: 3 cases with respiratory failure and/or dysphagia. (United States)

    Nakahara, Yukiko; Kawashima, Masatou; Matsushima, Toshio; Kouguchi, Motofumi; Takase, Yukinori; Nanri, Yusuke; Yakusiji, Yusuke


    It is well known that brainstem dysfunction may be caused by vascular compression of the medulla oblongata (MO). However, only a limited number of reports have found microvascular decompression (MVD) surgery to be an effective treatment for symptomatic patients with MO dysfunction, such as essential hypertension, pyramidal tract signs, dysphagia, and respiratory failure. This report describes 3 patients with vertebral artery compression of MO who presented with respiratory failure and/or dysphagia. MVD surgery using the transcondylar fossa approach was effective in relieving patient symptoms. Although the pathogenic mechanisms of symptomatic vertebral artery compression of MO remain unclear, we should recognize that MVD surgery is effective for selected patients with brainstem dysfunction. The transcondylar fossa approach and the stitched sling retraction technique are appropriate in MVD surgery to relieve vertebral artery compression of MO. Copyright © 2014 Elsevier Inc. All rights reserved.

  9. Standardized reporting of adverse events after microvascular decompression of cranial nerves; a population-based single-institution consecutive series

    DEFF Research Database (Denmark)

    Bartek, Jiri; Gulati, Sasha; Unsgård, Geirmund


    and 1 June 2013. Adverse events occurring within 30 days were classified according to the Landriel Ibanez classification for neurosurgical complications: grade I represents any non-life threatening complication treated without invasive procedures; grade II is complications requiring invasive management......OBJECTIVE: To investigate frequencies of adverse events occurring within 30 days after microvascular decompression (MVD) surgery using a standardized report form of adverse events. METHODS: We conducted a retrospective review of 98 adult patients (≥16 years) treated with MVD between 1 January 1994......; grade III is life-threatening adverse events requiring treatment in an intensive care unit (ICU); grade IV is death as a result of complications. We sought to compare our results with reports from the literature. RESULTS: Patients' median age was 61 years (range 26-83), and 64 (65 %) were females...

  10. Comparision of results between two different techniques of cranio-cervical decompression in patients with Chiari I malformation. (United States)

    Kunert, Przemysław; Janowski, Mirosław; Zakrzewska, Agnieszka; Marchel, Andrzej


    A variety of approaches are employed for treatment of Chiari I malformation. They differ in extent of cranio-c ervical decompression. A technique based on arachnoid preservation and duroplasty was introduced in our department in 2001. The aim of the study is to compare between the previous and the present technique. Retrospective analysis of 38 patients with Chiari I malformation treated between 1998 and 2004 was performed. The previous technique including arach- noid incision, coagulation of cerebellar tonsils, and fourth ventricle exploration without duroplasty was used to treat 21 patients (group 1). A further 17 patients were treated with the present technique consisting of arachnoid preservation and duroplasty (group 2). Complication rates as well as early and late results of treatment were evaluated. Karnofsky (KPS), Rankin (RS) and Bidziński (BS) scales were used for evaluation of results. Post-operative complications were detected in 9 patients in group 1 (43%). They included liquorrhoea (5 cases), meningitis (1 case), and symptoms progression (3 cases). There were no surgical complications in group 2 (p = 0.002). Neurological improvement in the early period (until discharge from hospital) occurred in 10 (48%) patients in group 1 and in 13 (76%) in group 2 (p = NS). Further improvement or lack of symptoms progression was found in 58% in group 1 and 82% in group 2 (p = NS). Assessment in KPS, RS and BS showed slightly better results of group 2 but the difference was statistically insignificant. Results of both techniques are comparable. The risk of post-operative complications after extra-arachnoid cranio-cervical decompression with duroplasty is, however, significantly lower.

  11. A novel and simple method using a transanal intestinal long tube for protecting intestinal anastomosis and decompressing the small bowel (United States)


    Purpose I introduce the use of transanal intestinal long tube (TILT) using nasogastric tube. TILT passes from anus to the anastomosis, helping to decompress a dilated bowel loop. Methods TILT procedure was limited to those patients predicting a severe luminal size discrepancy after intestinal anastomosis, and who had postoperative prolonged ileus. We retrospectively reviewed the medical records of 10 infants (7 male an 3 female patients) who were treated using the TILT procedure between 2012 and 2016. Results Median gestational age was 27+5 weeks and birth weight was 940 g. The first operation was done at a median of 4.5 days after birth due to necrotizing enterocolitis perforation (4 cases), isolated intestinal perforation (3 cases), meconium related ileus (1 case), congenital ileal volvulus (1 case), and ileal atresia (1 case). Nine cases of ileostomy closure were planned at a median of 130.5 days with a body weight of 3,060 g. For the ileal atresia case, TILT procedure without additional small bowel resection was performed to treat postoperative prolonged ileus. Nine out of ten were well functioned and defecation via anus was observed in a median of 4.5 days. Milk feeding began at a median of 6 days and the long intestinal tube was removed in a median of 14.5 days. Conclusion I suggested that TILT procedure could be a noninvasive operative option, predicting of size mismatched anastomosis causing prolonged ileus. Passive drainage of proximal intestinal contents might be helpful for decompress endoluminal pressure during the time of anastomosis healing with bowel movement recovery. PMID:28932729

  12. Operative Technique and Clinical Outcome in Endoscopic Core Decompression of Osteochondral Lesions of the Talus: A Pilot Study (United States)

    Beck, Sascha; Claßen, Tim; Haversath, Marcel; Jäger, Marcus; Landgraeber, Stefan


    Background Revitalizing the necrotic subchondral bone and preserving the intact cartilage layer by retrograde drilling is the preferred option for treatment of undetached osteochondral lesions of the talus (OLT). We assessed the effectiveness of Endoscopic Core Decompression (ECD) in treatment of OLT. Material/Methods Seven patients with an undetached OLT of the medial talar dome underwent surgical treatment using an arthroscopically-guided transtalar drill meatus for core decompression of the lesion. Under endoscopic visualization the OLT was completely debrided while preserving the cartilage layer covering the defect. The drill tunnel and debrided OLT were filled using an injectable bone graft substitute. Various clinical scores, radiographic imaging, and MRI were evaluated after a mean follow-up of 24.1 months. Results The American Orthopedic Foot and Ankle Society Score significantly improved from 71.0±2.4 to 90.3±5.9, and the Foot and Ankle Disability Index improved from 71.8±11.1 to 91.7±4.8. Radiographically, we observed good bone remodelling of the medial talar dome contour within 3 months. In MRI, an alteration of the bony signal of the drill tunnel and the excised OLT remained for more than 12 months. Conclusions First follow-up results for the surgical technique described in this study are highly promising for treatment of undetached stable OLT grade II or transitional stage II–III according to the Pritsch classification. Even lesions larger than 150 mm2 showed good clinical scores, with full restoration of the medial talar dome contour in radiographic imaging. PMID:27362485

  13. Statistical Compression for Climate Model Output (United States)

    Hammerling, D.; Guinness, J.; Soh, Y. J.


    Numerical climate model simulations run at high spatial and temporal resolutions generate massive quantities of data. As our computing capabilities continue to increase, storing all of the data is not sustainable, and thus is it important to develop methods for representing the full datasets by smaller compressed versions. We propose a statistical compression and decompression algorithm based on storing a set of summary statistics as well as a statistical model describing the conditional distribution of the full dataset given the summary statistics. We decompress the data by computing conditional expectations and conditional simulations from the model given the summary statistics. Conditional expectations represent our best estimate of the original data but are subject to oversmoothing in space and time. Conditional simulations introduce realistic small-scale noise so that the decompressed fields are neither too smooth nor too rough compared with the original data. Considerable attention is paid to accurately modeling the original dataset-one year of daily mean temperature data-particularly with regard to the inherent spatial nonstationarity in global fields, and to determining the statistics to be stored, so that the variation in the original data can be closely captured, while allowing for fast decompression and conditional emulation on modest computers.

  14. [Clinical study on spinal cord decompression combined with traditional Chinese medicine for the treatment of cervical spondylotic myelopathy]. (United States)

    Yang, Feng; Tan, Ming-Sheng; Yi, Ping; Tang, Xiang-Sheng; Hao, Qing-Ying; Qi, Ying-Na


    To compare the clinical effect between spinal card decompression combined with traditional Chinese medicine and simple spinal card decompression for cervical spondylotic myelopathy. From June 2012 to June 2015, 73 patients with cervical spondylotic myelopathy were treated, including 42 males and 31 females, aged from 29 to 73 years old with a mean of 50.9 years old. The patients were divided into the simple operation group (34 cases) and the operation combined with traditional Chinese medicine group(39 cases) according to the idea of themselves. The anterior discectomy or subtotal corpectomy with internal fixation or posterior simple open-door decompression with lateral mass screw fixation were performed in the patients. Among them, 39 cases were treated with traditional Chinese medicine after surgery. The Japanese orthopedic association (JOA) score of spinal cord function, the improvement rate of neural function, the neck dysfunction index (NDI) score and the governor vessel stasis syndrome score were compared between two groups preoperative and postoperative 1 week, 1 month and the final follow-up respectively. The internal fixation and the condition of spinal cord decompression were observed by CT, MRI and X-rays before and after operation. All the operations were successful, no injuries such as dura mater, spinal cord and nerve root were found. All the wounds were healed without infection except one patient had a superficial infection. It was solved after intermittent debridement and anti-infective therapy. Hematoma occurred in 1 case, complicated with spinal cord compression, caused incomplete paralysis, and promptly performed the re-operation to remove the hematoma without any obvious sequelae. All the patients were followed up from 12 to 24 months, (14.6±0.8) months for simple operation group and (13.5±0.7) months for operation combined with traditional Chinese medicine group, and there was no significant difference( P >0.05). The scores of JOA, NDI and

  15. Compressive system identification of LTI and LTV ARX models: The limited data set case

    NARCIS (Netherlands)

    Sanandaij, B. M.; Vincent, T. L.; Wakin, M. B.; Toth, R.; Poolla, K.


    In this paper, we consider identifying Auto Regressive with eXternal input (ARX) models for both Linear Time-Invariant (LTI) and Linear Time-Variant (LTV) systems. We aim at doing the identification from the smallest possible number of observations. This is inspired by the field of Compressive

  16. [The role of core decompression for the treatment of femoral head avascular necrosis in renal transplant recipients]. (United States)

    Zivcić-Cosić, Stela; Stalekar, Hrvoje; Mamula, Mihaela; Miletić, Damir; Orlić, Lidija; Racki, Sanjin; Cicvarić, Tedi


    subchondral radiolucencies in the lateral part of the head circumference spreading into the proximal part of the neck of the right femur, which indicated the presence of aseptic necrosis, but these changes could have also been caused by coxarthrosis. Unexpectedly, magnetic resonance imaging (MRI) did not reveal changes characteristic for avascular bone necrosis. Due to the progressively worsening of pain and the radiographic finding, the patient was submitted to decompression surgery of the femoral head. The surgical procedure was performed under diascopic guidance (C-arm) which allowed the correct positioning of a Kuerschner wire. A cannulated drill (diameter 4.0 mm) was placed over the wire and we performed two drillings of the spongiosis of the femoral head through to the subchondral area. Postoperatively, the patient was soon verticalized and advised to walk with crooks during a period of six weeks. This time is necessary to allow the mineralisation and strengthening of the bone which is now better vascularised. The patient recovered well and had no more pain. In renal transplant recipients it is most important to raise suspicion and verify the presence of avascular bone necrosis early, because timely bone decompression surgery can eliminate pain and cure the patient or it can prevent or delay bone destruction. When clinical signs of avascular bone necrosis arise and radiographic or standard MRI findings are negative, additional investigations (i.e. SPECT or MRI with contrast) should be performed to confirm or exclude the diagnosis. In latter phases of the disease, surgical decompression of the femoral head cannot lead to permanent amelioration, and it is inevitable to perform more invasive surgical procedures like "resurfacing" or bone grafting in younger patients, or the implantation of total hip endoprotheses.

  17. Change of occurance of type 1 and type 2 decompression sickness of divers treated at the Croatian Naval Medical Institute in the period from 1967 to 2000. (United States)

    Andrić, Dejan; Petri, Nadan M; Stipancević, Hrvoje; Petri, Lena Vranjković; Kovacević, Hasan


    A significant change of occurrence (p=0.0343) of type 1 and type 2 decompression sickness (DCS) of divers in Croatia was observed in the period from 1991 to 2002 (type 1: n=26, 37.68% and type 2: n=43, 62.32%) compared with the period from 1967 to 1990 (type 1: n=93, 52.84% and type 2: n=83, 47.16%). The change was attributed to the extensive usage of diving computers and artificial gas mixtures which enable extended bottom times and deeper dives, thus putting divers at an increased decompression risk. The importance of the results of this report is in the fact that permanent neurological deficit occurs only after type 2 DCS. Injured divers with permanent loss after type 2 DCS are not fit for diving and require a long term medical care, thus becoming a significant public health problem.

  18. Correct the Coagulopathy and Scoop It Out: Complete Reversal of Anuric Renal Failure through the Operative Decompression of Extraperitoneal Hematoma-Induced Abdominal Compartment Syndrome

    Directory of Open Access Journals (Sweden)

    Paul B. McBeth


    Full Text Available We report two cases of extraperitoneal compression of the intra-abdominal space resulting in abdominal compartment syndrome (ACS with overt renal failure, which responded to operative decompression of the extra-peritoneal spaces. This discussion includes patient presentation, clinical course, diagnosis, interventions, and outcomes. Data was collected from the patient’s electronic medical record and a radiology database. ACS appears to be a rare but completely reversible complication of both retroperitoneal hematoma (RH and rectus sheath hematoma (RSH. In patients with large RH or RSH consideration of intra-abdominal pressure (IAP monitoring combined with aggressive operative drainage after correction of the coagulopathy should be considered. These two cases illustrate how a relatively benign pathology can result in increased IAP, organ failure, and ultimately ACS. Intervention with decompressive laparotomy and evacuation of clot resulted in return to normal physiologic function.

  19. Functional outcome analysis of lumbar canal stenosis patients post decompression and posterior stabilization with stenosis grading using magnetic resonance imaging (United States)

    Pili, M.; Tobing, S. D. A. L.


    Lumbar canal stenosis (LCS) is a condition that can potentially cause disability. It often occurs in aging populations. The aim of this study was to analyze the correlation between the clinical outcomes of postoperative patients and classifications that were based on MRI assessments. This prospective cohort study was carried out at Cipto Mangunkusumo General Hospital from January to July 2016 using consecutive sampling. Thirty-eight patient samples were obtained, all of whom were managed with the same surgical technique of decompression and posterior stabilization. The patients were categorized in four types based on MRI examination using the Schizas classification. Pre- and post-treatment (three months and six months) assessments of the patients were conducted according to Visual Analogue Scale (VAS), the Oswestry Disability Index (ODI), the Japanese Orthopedic Association Score (JOA), and the Roland-Morris Disability Questionnaire (RMDQ). The statistical analysis was performed using the statistical program for social science (SPSS) v.19. The average age of the patients in this sample was 58.92 years (range 50-70 years). There were 16 males and 22 females. Most patients were classified as type C (21 subjects) based on MRI examination. The improvement in the clinical scores of male subjects was better than in the female subjects. Significant differences were found in the six-month postoperative VAS (p = 0.003) and three-month postoperative JOA scores (p = 0.029). The results at follow-up showed that the VAS, ODI, JOA and RMDQ scores were improved. There were no statistical differences between the MRI-based classification and the clinical outcomes at preoperative, three and six months postoperative according to VAS (p = 0.451, p = 0.738, p = 0.448), ODI (p = 0.143, p = 0.929, p = 0.796), JOA (p = 0.157, p = 0.876, p = 0.961), and RMDQ (p = 0.065, p = 0.057, p = 0.094). There was clinical improvement after decompression and posterior stabilization in lumbar canal

  20. Fluoroscopically-guided transnasal insertion of ileus tube intestinal decompression in patients with inoperable malignant bowel obstruction

    International Nuclear Information System (INIS)

    Fang Shiming; Li Haili; Lin Qing; Mao Aiwu; Wu Shaoqiu; Jiang Haosheng; Cao Yan; Wang Zhenlei


    Objective: To assess the technical feasibility and effectiveness of fluoroscopically-guided transnasal insertion of ileus tube for intestinal decompression in the treatment of inoperable malignant bowel obstruction. Methods: A total of 211 patients with inoperable malignant bowel obstruction were enrolled in this study. The median KPS scale was 40 (ranged from 20 to 60). Under fluoroscopic guidance, transnasal insertion of ileus tube by using conventional technique or guidewire-catheter exchange technique was performed in all patients. The technical success rate, the clinical effective rate, the curative rate and adverse reactions as well as complications were documented. The correlation among the obstructive sites, obstruction causes and therapeutic effectiveness was analyzed. The ileus tube used in this study was a four-cavity and double-balloon catheter with a diameter of 16 F/18 f, which is produced by Cliny Company. Results: Transnasal drainage tube was successfully inserted into the proximal jejunum in all 211 patients with malignant bowel obstruction, and the total technical success rate was 100%. The initial technical success rate of the traditional technique and the catheter-guidewire exchange method was 85.5% (65/76) and 100% (135/135) respectively, the difference between the two was significant (P<0.05). After 24 hours, the clinical remission rate in the patients with high-level intestinal obstruction, lower-level intestinal obstruction and colorectal obstruction was 95.8% (46/48), 92.9% (117/126) and 83.8% (31/37), respectively. A follow-up of 4-245 days (mean 138 days) was conducted, and the total clinical cure rate was 27.5% (58/211). The clinical cure rate in small intestine obstruction and colorectal obstruction caused by primary tumor or recurrence was 12.7% (20/157) and 59.5% (22/37), respectively (P<0.05). The adverse reactions and complications included uncomfortable pharynx feeling or pain (99.1%, 199/221), the tube obstruction (23.2%, 49

  1. Decompression from He-N2-O2 (TRIMIX) Bounce Dives Is Not More Efficient Than From He-O2 (HELIOX) Bounce Dives (United States)


    thermoregulation in a heliox atmosphere difficult, and the high speed of sound in helium can render speech unintelligible. However, none of these...surfacing). The principal purpose of these interviews was to establish standard times at which divers were definitely free of signs and symptoms of DCS...median thermal status score at the end of bottom time was 1 (very slight discomfort ). The median thermal status score at the end of decompression was 0

  2. An Annotated Bibliography of Hypobaric Decompression Sickness Research Conducted at the Crew Technology Division, USAF School of Aerospace Medicine, Brooks AFB, Texas from 1983 to 1988 (United States)


    AN ANNOTATED BIBLIOGRAPHY OF HYPOBARIC DECOMPRESSION SICKNESS RESEARCH CONDUCTED AT THE CREW TECHNOLOGY DIVISION, USAF SCHOOL OF AEROSPACE MEDICINE...190 man-flights to four selected altitudes (30000, 27500, 25000, and 22500 ft pressure equivalent) in a hypobaric chamber. The subjects’ ages ranged...conditions and two of these developed delayed sy~rtcms. Three of these five subjects underwent hyperbaric oxygen treatment. Conclusion. Female subjects

  3. [Arthroscopy-guided core decompression and bone grafting combined with selective arterial infusion for treatment of early stage avascular necrosis of femoral head]. (United States)

    Guo, Hao-Shan; Tian, Yi-Jun; Liu, Gang; An, Long; Zhou, Zhan-Guo; Liu, Huan-Zhen


    To observe the clinical effects of arthroscopy-guided core decompression and bone grafting combined with selective arterial infusion for early stage avascular necrosis of femoral head. From January 2010 to December 2014, 76 patients(76 hips) diagnosed as Ficat II stage avascular necrosis of femoral head were randomly divided into experimental group and control group. In the experimental group, there were 27 males and 8 females aged from 24 to 55 years old with an average of (43.96±6.81) years, treated with arthroscopic-guided core decompression and bone grafting combined with selective arterial infusion. Along the direction of the femoral neck, an 8 mm-diameter tunnel to necrotic areas was drilled, then curettage of necrotic bone was performed under arthroscope, and the iliac bone was grafted. In the control group, there were 29 males and 12 females aged from 26 to 56 years old with an average of (44.62±7.33) years, treated with percutaneous core decompression combined with selective arterial infusion. The preoperative and postoperative Harris scores were recorded and the changes of X-rays were analyzed. All the patients were followed up with an average of 30 months. Postoperative follow-up at 12 months showed that there was significant difference in imaging outcome between two groups( P 0.05), but there was significant difference in postoperative Harris score( P necrosis are effective. Using arthroscopic-guided core decompression method, the necrotic bone can be positioned and scraped more accurately, and can obtain better results. Copyright© 2018 by the China Journal of Orthopaedics and Traumatology Press.

  4. The Felix-trial. Double-blind randomization of interspinous implant or bony decompression for treatment of spinal stenosis related intermittent neurogenic claudication

    Directory of Open Access Journals (Sweden)

    Brand Ronald


    Full Text Available Abstract Background Decompressive laminotomy is the standard surgical procedure in the treatment of patients with canal stenosis related intermittent neurogenic claudication. New techniques, such as interspinous process implants, claim a shorter hospital stay, less post-operative pain and equal long-term functional outcome. A comparative (cost- effectiveness study has not been performed yet. This protocol describes the design of a randomized controlled trial (RCT on (cost- effectiveness of the use of interspinous process implants versus conventional decompression surgery in patients with lumbar spinal stenosis. Methods/Design Patients (age 40-85 presenting with intermittent neurogenic claudication due to lumbar spinal stenosis lasting more than 3 months refractory to conservative treatment, are included. Randomization into interspinous implant surgery versus bony decompression surgery will take place in the operating room after induction of anesthesia. The primary outcome measure is the functional assessment of the patient measured by the Zurich Claudication Questionnaire (ZCQ, at 8 weeks and 1 year after surgery. Other outcome parameters include perceived recovery, leg and back pain, incidence of re-operations, complications, quality of life, medical consumption, absenteeism and costs. The study is a randomized multi-institutional trial, in which two surgical techniques are compared in a parallel group design. Patients and research nurses are kept blinded of the allocated treatment during the follow-up period of 1 year. Discussion Currently decompressive laminotomy is the golden standard in the surgical treatment of lumbar spinal stenosis. Whether surgery with interspinous implants is a reasonable alternative can be determined by this trial. Trial register Dutch Trial register number: NTR1307

  5. Reducing intraocular-pressure spike after intravitreal-bevacizumab injection with ocular decompression using a sterile cotton swab soaked in proparacaine 0.5%: A quasi-experimental study. (United States)

    Qureshi, Naveed A; Mansoor, Hassan; Ahmad, Sabihuddin; Zafar, Sarah; Asif, Muhammad


    The study was conducted to determine the effect of preinjection ocular decompression by a cotton swab soaked in local anesthetic on the immediate postinjection rise in intraocular pressure (IOP) after intravitreal bevacizumab (IVB). A nonrandomized, quasi-experimental interventional study was conducted at Al-Shifa Trust Eye Hospital, Pakistan, from August 1, 2013 to July 31, 2014. One hundred ( n = 100) patients receiving 0.05-mL IVB injection for the first time were assigned to two preinjection anesthetic methods: one with ocular decompression using a sterile cotton swab soaked in proparacaine 0.5%, and the other without ocular decompression using proparacaine 0.5% eyedrops. The IOP was recorded in the eye receiving IVB at three time intervals: Time 1 (preinjection), Time 2 (immediately after injection), and Time 3 (30 minutes after injection). There was a significant difference in the mean IOP change (between Time 1 and Time 2) for the group injected with ocular decompression [ M = 1.00, standard deviation (SD) = 1.47] and the group injected without ocular decompression ( M = 5.00, SD = 2.38; t (68) = 9.761, p 0.5% experience significantly lower postinjection IOP spike, and that too for a considerably shorter duration as compared to those receiving IVB without ocular decompression.

  6. Single-stage posterior transforaminal lumbar interbody fusion, debridement, limited decompression, 3-column reconstruction, and posterior instrumentation in surgical treatment for single-segment lumbar spinal tuberculosis. (United States)

    Zeng, Hao; Wang, Xiyang; Zhang, Penghui; Peng, Wei; Liu, Zheng; Zhang, Yupeng


    The aim of this study is to determine the feasibility and efficacy of surgical management of single-segment lumbar spinal tuberculosis (TB) by using single-stage posterior transforaminal lumbar interbody fusion, debridement, limited decompression, 3-column reconstruction, and posterior instrumentation. Seventeen cases of single-segment lumbar TB were treated with single-stage posterior transforaminal lumbar interbody fusion, debridement, limited decompression, 3-column reconstruction, and posterior instrumentation. The mean follow-up was 36.9 months (range: 24-62 months). The kyphotic angle ranged from 15.2-35.1° preoperatively, with an average measurement of 27.8°. The American Spinal Injury Association (ASIA) score system was used to evaluate the neurological deficits and erythrocyte sedimentation rate (ESR) used to judge the activity of TB. Spinal TB was completely cured in all 17 patients. There was no recurrent TB infection. The postoperative kyphotic angle was 6.6-10.2°, 8.1° in average, and there was no significant loss of the correction at final follow-up. Solid fusion was achieved in all cases. Neurological condition in all patients was improved after surgery. Single-stage posterior transforaminal lumbar interbody fusion, debridement, limited decompression, 3-column reconstruction, and posterior instrumentation can be a feasible and effective method the in treatment of single-segment lumbar spinal TB.

  7. Evaluation of an impedance threshold device in patients receiving active compression-decompression cardiopulmonary resuscitation for out of hospital cardiac arrest. (United States)

    Plaisance, Patrick; Lurie, Keith G; Vicaut, Eric; Martin, Dominique; Gueugniaud, Pierre-Yves; Petit, Jean-Luc; Payen, Didier


    The purpose of this multicentre clinical randomized controlled blinded prospective trial was to determine whether an inspiratory impedance threshold device (ITD), when used in combination with active compression-decompression (ACD) cardiopulmonary resuscitation (CPR), would improve survival rates in patients with out-of-hospital cardiac arrest. Patients were randomized to receive either a sham (n = 200) or an active impedance threshold device (n = 200) during advanced cardiac life support performed with active compression-decompression cardiopulmonary resuscitation. The primary endpoint of this study was 24 h survival. The 24 h survival rates were 44/200 (22%) with the sham valve and 64/200 (32%) with the active valve (P = 0.02). The number of patients who had a return of spontaneous circulation (ROSC), intensive care unit (ICU) admission, and hospital discharge rates was 77 (39%), 57 (29%), and 8 (4%) in the sham valve group versus 96 (48%) (P = 0.05), 79 (40%) (P = 0.02), and 10 (5%) (P = 0.6) in the active valve group. Six out of ten survivors in the active valve group and 1/8 survivors in the sham group had normal neurological function at hospital discharge (P = 0.1). The use of an impedance valve in patients receiving active compression-decompression cardiopulmonary resuscitation for out-of-hospital cardiac arrest significantly improved 24 h survival rates.

  8. Urgent Optic Nerve Decompression via an Endoscopic Endonasal Transsphenoidal Approach for Craniopharyngioma in a 12-Month-Old Infant: A Case Report. (United States)

    Shibata, Teishiki; Tanikawa, Motoki; Sakata, Tomohiro; Mase, Mitsuhito


    Craniopharyngiomas are benign tumors and account for approximately 5.6-13% of all intracranial tumors in children. Diagnosis of pediatric craniopharyngioma is often delayed until the tumor becomes relatively large and manifests severe visual and/or endocrine disturbance. Endoscopic endonasal approaches have recently been introduced to surgery for craniopharyngioma. These techniques, however, have rarely been utilized in patients affected with craniopharyngioma as young as 1 year old. This report documents a 12-month-old male infant with sellar craniopharyngioma who presented with acute total vision loss. To increase the chances of visual recovery, an endoscopic endonasal optic nerve decompression was performed as an urgent procedure. After decompression, which resulted in improvement of his visual disturbance, gross total resection of the tumor was undertaken through an anterior interhemispheric approach at a later date. Tumor mass reduction through an endoscopic endonasal transsphenoidal approach followed by secondary radical total resection under craniotomy was considered to be useful in cases such as this when urgent optic nerve decompression is required. © 2018 S. Karger AG, Basel.

  9. Use of concentrated bone marrow aspirate and platelet rich plasma during minimally invasive decompression of the femoral head in the treatment of osteonecrosis. (United States)

    Martin, John R; Houdek, Matthew T; Sierra, Rafael J


    The aim of this paper is to describe our surgical procedure for the treatment of osteonecrosis of the femoral head using a minimally invasive technique. We have limited the use of this procedure for patients with pre-collapse osteonecrosis of the femoral head (Ficat Stage I or II). To treat osteonecrosis of the femoral head at our institution we currently use a combination of outpatient, minimally invasive iliac crest bone marrow aspirations and blood draw combined with decompressions of the femoral head. Following the decompression of the femoral head, adult mesenchymal stem cells obtained from the iliac crest and platelet rich plasma are injected into the area of osteonecrosis. Patients are then discharged from the hospital using crutches to assist with ambulation. This novel technique was utilized on 77 hips. Sixteen hips (21%) progressed to further stages of osteonecrosis, ultimately requiring total hip replacement. Significant pain relief was reported in 86% of patients (n=60), while the rest of patients reported little or no pain relief. There were no significant complications in any patient. We found that the use of a minimally invasive decompression augmented with concentrated bone marrow and platelet rich plasma resulted in significant pain relief and halted the progression of disease in a majority of patients.

  10. Elimination of CT-detected gas bubbles derived from decompression illness with abdominal symptoms after a short hyperbaric oxygen treatment in a monoplace chamber: a case report. (United States)

    Oyaizu, Takuya; Enomoto, Mitsuhiro; Tsujimoto, Toshihide; Kojima, Yasushi; Okawa, Atsushi; Yagishita, Kazuyoshi


    We report the case of a 54-year-old male compressed-air worker with gas bubbles detected by computed tomography (CT). He had complained of strong abdominal pain 30 minutes after decompression after working at a pressure equivalent to 17 meters of sea water for three hours. The initial CT images revealed gas bubbles in the intrahepatic portal vein, pulmonary artery and bilateral femoral vein. After the first hyperbaric oxygen treatment (HBO₂ at 2.5 atmospheres absolute/ATA for 150 minutes), no bubbles were detected on repeat CT examination. The patient still exhibited abdominal distension, mild hypesthesia and slight muscle weakness in the upper extremities. Two sessions of U.S. Navy Treatment Table 6 (TT6) were performed on Days 6 and 7 after onset. The patient recovered completely on Day 7. This report describes the important role of CT imaging in evaluating intravascular gas bubbles as well as eliminating the diagnosis of other conditions when divers or compressed-air workers experience uncommon symptoms of decompression illness. In addition, a short treatment table of HBO₂ using non-TT6 HBO₂ treatment may be useful to reduce gas bubbles and the severity of decompression illness in emergent cases. Copyright© Undersea and Hyperbaric Medical Society.

  11. Clinical Effects of Novel Nanoscaled Core Decompression Rods Combined with Umbilical Cord Mesenchymal Stem Cells on the Treatment of Early Osteonecrosis of the Femoral Head

    Directory of Open Access Journals (Sweden)

    Hongyang Gao


    Full Text Available Osteonecrosis of the femoral head (ONFH is one of the most common diseases in orthopedics. In this study, we investigated the clinical effects of novel nanoscaled core decompression rods combined with mesenchymal stem cells on the treatment of the ONFH. 12 adult patients with early ONFH (at the stage of Ficat II received the treatment using the implantation of novel nanoscaled core decompression rods combined with umbilical cord mesenchymal stem cells. The grade of the patients’ hip was scored by Harris marking system before and after the surgery, and then paired t-test was done. We assessed the curative efficiency based on the change of the patients before and after the surgery. In particular, the survival rate of femoral head was assessed at 12 months after the surgery. The results demonstrated that according to the standard of Harris Scoring, the average grade of hip joint before the surgery was 54.16 ± 4.23 points while average grade of hip joint at 12 months after the surgery was 85.28 ± 3.65 points. So, the implantation of the novel nanoscaled core decompression rods combined with mesenchymal stem cells had satisfactory clinical effects, suggesting that this implantation should be effective to treat early ONFH.

  12. Hemicraniectomy after middle cerebral artery infarction with life-threatening Edema trial (HAMLET). Protocol for a randomised controlled trial of decompressive surgery in space-occupying hemispheric infarction. (United States)

    Hofmeijer, Jeannette; Amelink, G Johan; Algra, Ale; van Gijn, Jan; Macleod, Malcolm R; Kappelle, L Jaap; van der Worp, H Bart


    Patients with a hemispheric infarct and massive space-occupying brain oedema have a poor prognosis. Despite maximal conservative treatment, the case fatality rate may be as high as 80%, and most survivors are left severely disabled. Non-randomised studies suggest that decompressive surgery reduces mortality substantially and improves functional outcome of survivors. This study is designed to compare the efficacy of decompressive surgery to improve functional outcome with that of conservative treatment in patients with space-occupying supratentorial infarction The study design is that of a multi-centre, randomised clinical trial, which will include 112 patients aged between 18 and 60 years with a large hemispheric infarct with space-occupying oedema that leads to a decrease in consciousness. Patients will be randomised to receive either decompressive surgery in combination with medical treatment or best medical treatment alone. Randomisation will be stratified for the intended mode of conservative treatment (intensive care or stroke unit care). The primary outcome measure will be functional outcome, as determined by the score on the modified Rankin Scale, at one year.

  13. Microvascular decompression in treating cranial nerve diseases%微血管减压术治疗颅神经疾病疗效分析

    Institute of Scientific and Technical Information of China (English)

    张志强; 黄涛; 罗小川; 谢才军; 谢绍盈; 沈有碧; 隋立森; 韩富


    Objective To study the efficacy of microvascular decompression in treating cranial nerve diseases. Methods 156 patients were treated with microvaseular decompression,of whom 119 were with trigeminal neuralgia,34 with hemifacial spasm and three with glossopharyngeal neuralgia.Rusults The overall effective rate was 96.8%(151/156) and the corresponding effective rate for the above three conditions were 94.2%,97.1% and 66.7%. Conlusions Mierovaseular decompression iS an effective treatment for cranial nerve diseases.%目的 探讨微血管减压术治疗三叉神经痛、面肌痉挛、舌咽神经痛的疗效. 方法 微血管减压手术治疗颅神经疾病156例(三叉神经痛119例,面肌痉挛34例,舌咽神经痛3例). 结果 总有效151例,有效率96.8%,其中三又神经痛、面肌痉挛和舌咽神经痛患者手术有效率分别为94.2%、97.1%和66.7%. 结论 微血管减压术治疗颅神经疾病疗效确切.

  14. Treatment of herniated lumbar disc by percutaneous laser disc decompression combined with synchronous suction technique through syringe

    Institute of Scientific and Technical Information of China (English)

    Dhir B. Gurung; Gaojian Tao; Hongyi Lin; Yanning Qian; Jian Lin


    Objective: To compare the outcomes of percutaneous laser disc decompression (PLDD) and PLDD with synchronous suction through syringe in the patients with herniated lumbar disc (HLD). Methods: Forty-two patients with HLD on MRI and those who did not respond to conservative treatment for 6 weeks were randomly divided into group A and group B. In group A, the patients were treated with PLDD and those in group B with PLDD and synchronous suction through syringe. GaAIAS diode laser at 810 nm was used for the ablation in both groups. The treatment effect was evaluated by modified MacNab's criteria on the 7th, 30th and 90th day. Results: Evaluated by modified MacNab's criteria, the percentages of the excellent and good cases in total patients treated for group B and A were 80.95% and 57.14% on the 7th follow-up day, 85.71% and 66.67% on the 30th follow-up day, and 95.24% and 71.43% on the 90th follow-up day, respectively. Conclusion: Synchronous suction technique through syringe during PLDD improves the overall outcome in the treatment of herniated lumbar disc.

  15. Epiduroscopic laser neural decompression%硬膜外镜下激光神经减压术

    Institute of Scientific and Technical Information of China (English)

    Dae Hyun Jo; 刘华琴


    硬膜外镜下激光神经减压术(ELND)是用于诊断和治疗慢性后背痛有用的方法.它较传统介入技术创伤大,但比手术治疗方法创伤小.在治疗操作过程中,通过硬膜外镜在去除病源时还能够观察到硬膜外腔的病理状况.但是掌握ELND需要相当长的时间.%Epiduroscopic laser neural decompression(ELND) is a very useful tool for diagnosis and treatment of chronic low back pain.It is more invasive than conventional intervention technique,but less invasive than surgery.Epiduroscopy can watch the pathology conditions in the epidural space during the procedure as well as remove the pain sources at the same time.ELND has a very slow learning curve.

  16. Prospective Study of Neuroendoscopy versus Microscopy: 213 Cases of Microvascular Decompression for Trigeminal Neuralgia Performed by One Neurosurgeon. (United States)

    Xiang, Hui; Wu, Guangyong; Ouyang, Jia; Liu, Ruen


    To compare the efficacy and complications of microvascular decompression (MVD) by complete neuroendoscopy versus microscopy for 213 cases of trigeminal neuralgia (TN). Between January 2014 and January 2016, 213 patients with TN were randomly assigned to the neuroendoscopy (n = 105) or microscopy (n = 114) group for MVD via the suboccipital retrosigmoid approach. All procedures were performed by the same neurosurgeon. Follow-up was conducted by telephone interview. Statistical data were analyzed with the chi-square test, and a probability (P) value of ≤0.05 was considered statistically significant. Chi-square test was conducted using SAS 9.4 software (SAS Institute, Cary, North Carolina, USA). There were no statistical differences between the 2 groups in pain-free condition immediately post procedure, pain-free condition 1 year post procedure, hearing loss, facial hypoesthesia, transient ataxia, aseptic meningitis, intracranial infections, and herpetic lesions of the lips. There were no instances of death, facial paralysis, cerebral hemorrhage, or cerebrospinal fluid leakage in either group. There were no significant differences in the cure rates or incidences of surgical complications between neuroendoscopic and microscopic MVD. Copyright © 2017 Elsevier Inc. All rights reserved.

  17. Inspiratory impedance during active compression-decompression cardiopulmonary resuscitation: a randomized evaluation in patients in cardiac arrest. (United States)

    Plaisance, P; Lurie, K G; Payen, D


    Blood pressure is severely reduced in patients in cardiac arrest receiving standard cardiopulmonary resuscitation (CPR). Although active compression-decompression (ACD) CPR improves acute hemodynamic parameters, arterial pressures remain suboptimal with this technique. We performed ACD CPR in patients with a new inspiratory threshold valve (ITV) to determine whether lowering intrathoracic pressures during the "relaxation" phase of ACD CPR would enhance venous blood return and overall CPR efficiency. This prospective, randomized, blinded trial was performed in prehospital mobile intensive care units in Paris, France. Patients in nontraumatic cardiac arrest received ACD CPR plus the ITV or ACD CPR alone for 30 minutes during advanced cardiac life support. End tidal CO(2) (ETCO(2)), diastolic blood pressure (DAP) and coronary perfusion pressure, and time to return of spontaneous circulation (ROSC) were measured. Groups were similar with respect to age, gender, and initial rhythm. Mean maximal ETCO(2), coronary perfusion pressure, and DAP values, respectively (in mm Hg), were 13.1+/-0.9, 25.0+/-1.4, and 36.5+/-1.5 with ACD CPR alone versus 19.1+/-1.0, 43.3+/-1.6, and 56.4+/-1.7 with ACD plus valve (PCPR alone after 26.5+/-0.7 minutes versus 4 of 11 patients with ACD CPR plus ITV after 19.8+/-2.8 minutes (PCPR increases the efficiency of CPR, leading to diastolic arterial pressures of >50 mm Hg. The long-term benefits of this new CPR technology are under investigation.

  18. Decompression sickness among diving fishermen in Mexico: observational retrospective analysis of DCS in three sea cucumber fishing seasons. (United States)

    Huchim-Lara, Oswaldo; Chin, Walter; Salas, Silvia; Rivera-Canul, Normando; Cordero-Romero, Salvador; Tec, Juan; Joo, Ellie; Mendez-Dominguez, Nina


    The probabilities of decompression sickness (DCS) among diving fishermen are higher than in any other group of divers. Diving behavior of artisanal fishermen has been directed mainly to target high-value species. The aim of this study was to learn about the occurrence of DCS derived from sea cucumber harvesting in the Yucatán Peninsula, Mexico. We conducted a retrospective chart review of diving fishermen treated at a multiplace hyperbaric chamber in Tizimín, Mexico. In total, 233 recompression therapies were rendered to 166 diving fishermen from 2014 to