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Sample records for endonasal transsphenoidal approach

  1. Endoscopic Endonasal Transsphenoidal Approach for Apoplectic Pituitary Tumor: Surgical Outcomes and Complications in 45 Patients.

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    Zhan, Rucai; Li, Xueen; Li, Xingang

    2016-02-01

    Objective To assess the safety and effectiveness of the endoscopic endonasal transsphenoidal approach (EETA) for apoplectic pituitary adenoma. Design A retrospective study. Setting Qilu Hospital of Shandong University; Brain Science Research Institute, Shandong University. Participants Patients admitted to Qilu Hospital of Shandong University who were diagnosed with an apoplectic pituitary tumor and underwent EETA for resection of the tumor. Main Outcome Measures In total 45 patients were included in a retrospective chart review. Data regarding patient age, sex, presentation, lesion size, surgical procedure, extent of resection, clinical outcome, and surgical complications were obtained from the chart review. Results In total, 38 (92.7%) of 41 patients with loss of vision obtained visual remission postoperatively. In addition, 16 patients reported a secreting adenoma, and postsurgical hormonal levels were normal or decreased in 14 patients. All other symptoms, such as headache and alteration of mental status, recovered rapidly after surgery. Two patients (4.4%) incurred cerebrospinal fluid leakage. Six patients (13.3%) experienced transient diabetes insipidus (DI) postoperatively, but none of these patients developed permanent DI. Five patients (11.1%) developed hypopituitarism and were treated with replacement of hormonal medicine. No cases of meningitis, carotid artery injury, or death related to surgery were reported. Conclusion EETA offers a safe and effective surgical option for apoplectic pituitary tumors and is associated with low morbidity and mortality.

  2. Clinical Pearls in Anaesthesia for Endoscopic Endonasal Transsphenoid Pituitary Macroadenoma Surgery

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    Shah Shagun B

    2015-11-01

    Full Text Available Endoscopic Endonasal Trans-sphenoid Surgery (EETS aided by avant-garde neuro-navigation techniques, ultrasonic aspirators and bone curettes has come of age. Endoscopic surgery supersedes conventional microscopic approach due to better visualization, avoidance of craniotomy, brain retraction and undue neurovascular manipulation with less morbidity, blood loss and improved safety. Anaesthetic techniques must be tailored to cater for such advances in surgery.

  3. Anatomic Changes Caused by Endoscopic Endonasal Transsphenoidal Surgery and Their Effects on Nasal Functions.

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    Kim, Do Hyun; Hong, Yong-Kil; Jeun, Sin-Soo; Park, Yong Jin; Kim, Soo Whan; Cho, Jin Hee; Kim, Boo Young; Han, Sungwoo; Jung, Young Hoon; Lee, Yong Joo; Kim, Sung Won

    2016-06-01

    We evaluated postoperative changes in nasal cavity dimensions and their effects on nasal functions and symptoms. Case series with chart review. Tertiary referral center. We studied patients who underwent binostril, 4-hand endoscopic endonasal transsphenoidal approach surgery with the bilateral modified nasoseptal rescue flap technique. Pre- and postoperative paranasal computed tomography scans were used to assess nasal cavity dimensional changes at 4 levels. We also performed several pre- and postoperative tests, including the Connecticut Chemosensory Clinical Research Center test and the Cross-Cultural Smell Identification Test (n = 119) to evaluate olfactory functions. Also, the Nasal Obstruction Symptoms Evaluation, the Sino-Nasal Outcome Test-20, and a visual analog scale were used (n = 157) to record subjective symptoms. We compared these data with the pre- and postoperative nasal cavity dimensions. Two-dimensional objective increases in nasal passage dimensions were evident postoperatively (all cross-sectional areas, P Cultural Smell Identification Test (all cross-sectional areas, P ≥ .05). Endoscopic endonasal transsphenoidal approach surgery altered the patients' nasal anatomy, but the changes in nasal cavity dimensions did not affect nasal functions and symptoms. These results will help surgeons to appropriately expose the surgical field during endoscopic endonasal transsphenoidal approach surgery. © American Academy of Otolaryngology—Head and Neck Surgery Foundation 2016.

  4. Endoscopic endonasal transsphenoidal approach for pituitary adenomas: technical aspects and report of casuistic Abordagem endoscópica endonasal para adenomas de hipófise: aspectos técnicos e relato de casuística

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    Américo Rubens Leite dos Santos

    2010-08-01

    Full Text Available OBJECTIVE: Analyse technical aspects, effectiveness and morbidity of the endoscopic endonasal transphenoidal approach for pituitary adenomas. METHOD: From January 2005 to September 2008, 30 consecutive patients underwent endoscopic endonasal resection of pituitary adenomas with a follow up from 3 to 36 months. Their medical charts were retrospectively analysed. RESULTS: There were 18 women and 12 men, mean age 44 years (range 17-65 yr. Among the 30 patients, 23 had macroadenomas and 7 microadenomas. Twelve patients had non-functioning tumors, 9 had ACTH-secreting tumors, 8 had GH-secreting tumors and 1 prolactinoma. Complete resection and hormonal control was achieved in all microadenomas. Macroadenomas were completely removed in 6 patients, subtotal resection in 6 and partial resection in 11. Three patients had diabetes insipidus and 5 had CSF leaks treated with lumbar drainage. CONCLUSION: The endonasal endoscopic approach for pituitary tumors is effective and has low morbidity.OBJETIVO: Analisar aspectos técnicos, eficácia e morbidade do acesso transesfenoidal endonasal endoscópico para adenomas hipofisários. MÉTODO: Estudo retrospectivo de trinta pacientes consecutivos submetidos à ressecção endoscópica endonasal de adenomas hipofisários, entre janeiro de 2005 e setembro de 2008, com seguimento pós-operatório entre três e 36 meses. RESULTADOS: Foram operados 18 mulheres e 12 homens com idades variando entre 17 e 65 anos (média 44 anos. Entre os 30 casos operados, 23 eram macroadenomas e sete microadenomas. Doze pacientes apresentavam adenomas não-funcionantes, nove tumores secretores de ACTH, oito tumores secretores de GH e um prolactinoma. Ressecção macroscópica completa e controle endócrino foram conseguidos em todos microadenomas. Ressecção dos macroadenomas foi completa em seis pacientes, subtotal em seis e parcial em seis casos. Três pacientes desenvolveram diabetes insipidus e cinco tiveram fístula liqüórica p

  5. The development of a virtual simulator for training neurosurgeons to perform and perfect endoscopic endonasal transsphenoidal surgery.

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    Rosseau, Gail; Bailes, Julian; del Maestro, Rolando; Cabral, Anne; Choudhury, Nusrat; Comas, Olivier; Debergue, Patricia; De Luca, Gino; Hovdebo, Jordan; Jiang, Di; Laroche, Denis; Neubauer, Andre; Pazos, Valerie; Thibault, Francis; Diraddo, Robert

    2013-10-01

    A virtual reality (VR) neurosurgical simulator with haptic feedback may provide the best model for training and perfecting surgical techniques for transsphenoidal approaches to the sella turcica and cranial base. Currently there are 2 commercially available simulators: NeuroTouch (Cranio and Endo) developed by the National Research Council of Canada in collaboration with surgeons at teaching hospitals in Canada, and the Immersive Touch. Work in progress on other simulators at additional institutions is currently unpublished. This article describes a newly developed application of the NeuroTouch simulator that facilitates the performance and assessment of technical skills for endoscopic endonasal transsphenoidal surgical procedures as well as plans for collecting metrics during its early use. The main components of the NeuroTouch-Endo VR neurosurgical simulator are a stereovision system, bimanual haptic tool manipulators, and high-end computers. The software engine continues to evolve, allowing additional surgical tasks to be performed in the VR environment. Device utility for efficient practice and performance metrics continue to be developed by its originators in collaboration with neurosurgeons at several teaching hospitals in the United States. Training tasks are being developed for teaching 1- and 2-nostril endonasal transsphenoidal approaches. Practice sessions benefit from anatomic labeling of normal structures along the surgical approach and inclusion (for avoidance) of critical structures, such as the internal carotid arteries and optic nerves. The simulation software for NeuroTouch-Endo VR simulation of transsphenoidal surgery provides an opportunity for beta testing, validation, and evaluation of performance metrics for use in neurosurgical residency training. CTA, cognitive task analysisVR, virtual reality.

  6. Using an autologous fibrin sealant in the preventing of cerebrospinal fluid leak with large skull base defect following endoscopic endonasal transsphenoidal surgery.

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    Yildirim, Ali Erdem; Dursun, Engin; Ozdol, Cagatay; Divanlioglu, Denizhan; Nacar, Osman Arikan; Koyun, Oguz Kara; Ilmaz, Adil Ery; Belen, Ahmed Deniz

    2013-01-01

    Postoperative cerebrospinal fluid (CSF) leak following endoscopic endonasal transsphenoidal surgery (EETS) is associated with increased morbidity and mortality. This prospective study is the first evaluation of using autologous fibrin sealant for preventing postoperative CSF leak and related complications. 200 endoscopic endonasal transsphenoidal approaches were included in the study and reviewed retrospectively from September 2010 to June 2012. A total of 55 patients who have large skull base and diafragma sella defects, connected with basal cisterns or ventricles, were chosen for the study. The patients were operated via extended or classical endoscopic endonasal transsphenoidal approach. The skull base has been repaired using AFS combined with multilayer reconstruction in all cases. The incidence of CSF leak as a complication of EETS was analyzed. The ages of the patients ranged from 20 to 83 years (mean 49.3 years). There were 25 (46%) male patients and 30 (54%) females. All patients had tumors with suprasellar or parasellar extension. Postoperative CSF leak was determined in 2 patients (3.6%). There were no complications and allergic reactions associated with the use of AFS. Using of AFS combined with multilayer reconstruction technique is a safe and effective method to prevent CSF leak in large defects following EETS.

  7. Visual Outcome of an Endoscopic Endonasal Transsphenoidal Approach in Pituitary Macroadenomas: Quantitative Assessment with Diffusion Tensor Imaging Early and Long-Term Results.

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    Anik, Ihsan; Anik, Yonca; Cabuk, Burak; Caklili, Melih; Pirhan, Dilara; Ozturk, Onural; Cirak, Musa; Ceylan, Savas

    2018-02-21

    Postoperative visual recovery in patients with pituitary adenoma can be influenced by the duration of symptoms, age, and tumor volume. Diffusion tensor imaging (DTI) allows visualization of white matter structure along with quantitative information. The aims of our study were to predict the visual recovery process in the early and long-term periods and to define the parameters affecting the recovery course. A total of 200 patients with pituitary macroadenomas underwent endoscopic transsphenoidal surgery between January 2009 and July 2016. DTI and visual analysis including visual acuity and visual field analyses were performed for these patients at 5 periods, which included 3 years of follow-up. The effects of age, duration of symptoms, and tumor volume on visual recovery were evaluated. Mean tumor volume was calculated as 8871 ± 2758 mm 3 and mean symptom duration was 23.41 ± 3.72 weeks. Mean age of the patients was 43.8 ± 8.9 years in the full recovery group and 48.7 ± 15.1 years in the nonrecovery group. Visual field analysis results on a Humphrey visual chart showed a significant linear strong correlation with fractional anisotropy (FA) values and a reverse strong correlation with mean diffusivity (MD) values on DTI magnetic resonance. DTI FA and MD cutoff values for each group were respectively determined as 0.373 and 1386 (×10 -6 mm 2 /second) for the preoperative period, 0.423 and 1383 (×10 -6 mm 2 /second) for the initial period, 0.428 and 1265 (×10 -6 mm 2 /second) for the early period, 0.432 and 1238 (×10 -6 mm 2 /second) for the intermediate period, and 0.437 and 1198 (×10 -6 mm 2 /second) for the late period. DTI can assess and predict visual recovery after endoscopic transsphenoidal surgery of patients with pituitary macroadenomas causing chiasmal compression. FA values lower than or MD values greater than the cutoff values of the specific period reflect poor prognosis. Tumor volume was found to be the featured parameter that affects visual

  8. Endoscopic augmented reality navigation system for endonasal transsphenoidal surgery to treat pituitary tumors: technical note.

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    Kawamata, Takakazu; Iseki, Hiroshi; Shibasaki, Takao; Hori, Tomokatsu

    2002-06-01

    Endoscopes have been commonly used in transsphenoidal surgery to treat pituitary tumors, to compensate for the narrow surgical field. Although many navigation systems have been introduced for neurosurgical procedures, there have been few reports of navigation systems for endoscopic operations. This report presents our recently developed, endoscopic, augmented reality (AR) navigation system. The technology is based on the principles of AR environment technology. The system consisted of a rigid endoscope with light-emitting diodes, an optical tracking system, and a controller. The operation of the optical tracking system was based on two sets of infrared light-emitting diodes, which measured the position and orientation of the endoscope relative to the patient's head. We used the system during endonasal transsphenoidal operations to treat pituitary tumors in 12 recent cases. Anatomic, "real," three-dimensional, virtual images of the tumor and nearby anatomic structures (including the internal carotid arteries, sphenoid sinuses, and optic nerves) were superimposed on real- time endoscopic live images. The system also indicated the positions and directions of the endoscope and the endoscopic beam in three-dimensional magnetic resonance imaging or computed tomographic planes. Furthermore, the colors of the wire-frame images of the tumor changed according to the distance between the tip of the endoscope and the tumor. These features were superior to those of conventional navigation systems, which are available only for operating microscopes. The endoscopic AR navigation system allows surgeons to perform accurate, safe, endoscope-assisted operations to treat pituitary tumors; it is particularly useful for reoperations, in which midline landmarks may be absent. We consider the AR navigation system to be a promising tool for safe, minimally invasive, endonasal, transsphenoidal surgery to treat pituitary tumors.

  9. Endoscopic endonasal transsphenoidal surgery using the iArmS operation support robot: initial experience in 43 patients.

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    Ogiwara, Toshihiro; Goto, Tetsuya; Nagm, Alhusain; Hongo, Kazuhiro

    2017-05-01

    Objective The intelligent arm-support system, iArmS, which follows the surgeon's arm and automatically fixes it at an adequate position, was developed as an operation support robot. iArmS was designed to support the surgeon's forearm to prevent hand trembling and to alleviate fatigue during surgery with a microscope. In this study, the authors report on application of this robotic device to endoscopic endonasal transsphenoidal surgery (ETSS) and evaluate their initial experiences. Methods The study population consisted of 43 patients: 29 with pituitary adenoma, 3 with meningioma, 3 with Rathke's cleft cyst, 2 with craniopharyngioma, 2 with chordoma, and 4 with other conditions. All patients underwent surgery via the endonasal transsphenoidal approach using a rigid endoscope. During the nasal and sphenoid phases, iArmS was used to support the surgeon's nondominant arm, which held the endoscope. The details of the iArmS and clinical results were collected. Results iArmS followed the surgeon's arm movement automatically. It reduced the surgeon's fatigue and stabilized the surgeon's hand during ETSS. Shaking of the video image decreased due to the steadying of the surgeon's scope-holding hand with iArmS. There were no complications related to use of the device. Conclusions The intelligent armrest, iArmS, seems to be safe and effective during ETSS. iArmS is helpful for improving the precision and safety not only for microscopic neurosurgery, but also for ETSS. Ongoing advances in robotics ensure the continued evolution of neurosurgery.

  10. Endoscopic repair of transsellar transsphenoidal meningoencephalocele; case report and review of approaches

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    Maryam Jalessi, M.D.

    2015-06-01

    Full Text Available We present an extremely rare case of transsellar transsphenoidal meningoencephalocele in a 36-year-old woman with pituitary dwarfism complaining of nasal obstruction. Imaging studies showed a bony defect in the sellar floor and sphenoid sinus with huge nasopharyngeal mass and 3rd ventricle involvement. Using endoscopic endonasal approach the sac was partially removed and the defect was reconstructed with fat and fascial graft, and buttressed with titanium mesh and septal flap. Visual field improvement was noticed post-operatively and no complication was encountered during follow-up. So, endoscopic endonasal approach with partial resection of the sac is a safe and effective treatment for this disease

  11. Comparative analysis of outcomes following craniotomy and expanded endoscopic endonasal transsphenoidal resection of craniopharyngioma and related tumors: a single-institution study.

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    Jeswani, Sunil; Nuño, Miriam; Wu, Arthur; Bonert, Vivien; Carmichael, John D; Black, Keith L; Chu, Ray; King, Wesley; Mamelak, Adam N

    2016-03-01

    Craniopharyngiomas and similar midline suprasellar tumors have traditionally been resected via transcranial approaches. More recently, expanded endoscopic endonasal transsphenoidal approaches have gained interest. Surgeons have advocated for both approaches, and at present there is no consensus whether one approach is superior to the other. The authors therefore compared surgical outcomes between craniotomy and endoscopic endonasal transsphenoidal surgery (EETS) for suprasellar tumors treated at their institution. A retrospective review of patients undergoing resection of suprasellar lesions at Cedars-Sinai Medical Center between 2000 and 2013 was performed. Patients harboring suspected craniopharyngioma were selected for extensive review. Other pathologies or predominantly intrasellar masses were excluded. Cases were separated into 2 groups, based on the surgical approach taken. One group underwent EETS and the other cohort underwent craniotomy. Patient demographic data, presenting symptoms, and previous therapies were tabulated. Preoperative and postoperative tumor volume was calculated for each case based on MRI. Student t-test and the chi-square test were used to evaluate differences in patient demographics, tumor characteristics, and outcomes between the 2 cohorts. To assess for selection bias, 3 neurosurgeons who did not perform the surgeries reviewed the preoperative imaging studies and clinical data for each patient in blinded fashion and indicated his/her preferred approach. These data were subject to concordance analysis using Cohen's kappa test to determine if factors other than surgeon preference influenced the choice of surgical approach. Complete data were available for 53 surgeries; 19 cases were treated via EETS, and 34 were treated via craniotomy. Patient demographic data, preoperative symptoms, and tumor characteristics were similar between the 2 cohorts, except that fewer operations for recurrent tumor were observed in the craniotomy cohort

  12. History of endonasal skull base surgery.

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    Wang, Amy J; Zaidi, Hasan A; Laws, Edward D

    2016-12-01

    While the endonasal approach to the skull base continues to advance, this paper invokes its long history. The centuries of medieval neuroanatomy and early neurosurgery enabled the conception of the first transfacial approaches in the late 1800s; Henry Schloffer performed the first transsphenoidal surgery in 1907. Although the procedure was initially met with much interest, Harvey Cushing eventually led the field of neurosurgery to abandon the transsphenoidal approach in the 1920s. The following three generations of neurosurgeons contained several key figures including Norman Dott, Gerard Guiot, and Jules Hardy who were steadfast in preserving the technique as well as in addressing its shortcomings. The endoscopic approach developed simultaneously, and advances in magnifying and fiberoptics further resolved limitations previously inherent to the transsphenoidal approach. At last, in the 1960s, the transsphenoidal approach entered its renaissance. Today, the momentum of its development persists in the endoscopic endonasal approach, which has recently expanded the indications for transsphenoidal surgery across the skull base, far beyond its original jurisdiction of the sella. Continued progress must not take for granted the rich history of the transsphenoidal approach, which was developed over centuries by surgeons around the world. The authors present the evolution of modern endonasal surgery as a dynamic interplay between technology, medicine, and surgery over the past 100 years. Progress can be attributed to courageous surgeons who affirmed their contemporary practices despite gaps in technology or medicine, and to visionary individuals who produced and incorporated new elements into transsphenoidal surgery. And so while the new endoscopic technique brings forth new challenges, its development reaffirms the principles laid down by the pioneers of transsphenoidal surgery.

  13. Endoscopic endonasal approach for mass resection of the pterygopalatine fossa

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    Jan Plzák

    Full Text Available OBJECTIVES: Access to the pterygopalatine fossa is very difficult due to its complex anatomy. Therefore, an open approach is traditionally used, but morbidity is unavoidable. To overcome this problem, an endoscopic endonasal approach was developed as a minimally invasive procedure. The surgical aim of the present study was to evaluate the utility of the endoscopic endonasal approach for the management of both benign and malignant tumors of the pterygopalatine fossa. METHOD: We report our experience with the endoscopic endonasal approach for the management of both benign and malignant tumors and summarize recent recommendations. A total of 13 patients underwent surgery via the endoscopic endonasal approach for pterygopalatine fossa masses from 2014 to 2016. This case group consisted of 12 benign tumors (10 juvenile nasopharyngeal angiofibromas and two schwannomas and one malignant tumor. RESULTS: No recurrent tumor developed during the follow-up period. One residual tumor (juvenile nasopharyngeal angiofibroma that remained in the cavernous sinus was stable. There were no significant complications. Typical sequelae included hypesthesia of the maxillary nerve, trismus, and dry eye syndrome. CONCLUSION: The low frequency of complications together with the high efficacy of resection support the use of the endoscopic endonasal approach as a feasible, safe, and beneficial technique for the management of masses in the pterygopalatine fossa.

  14. A transseptal approach in transsphenoidal surgery for pituitary (hypophyseal) tumors

    International Nuclear Information System (INIS)

    Gierek, T.; Galuszko-Ignasiak, B.; Krauze, J.; Rudnik, A.

    1994-01-01

    The authors described the direct transseptal approach in transsphenoidal surgery for hypophyseal tumors. This route gives a good insight into the area of the sella. The above mentioned method is also less destructive to nasal structures in the nasal cavity, because preserves the anterior nasal septum. It is uniformity of actually views of rhinological school. 20 patients were operated using this method and none of them noticed the changes of nasal airway and the sense of smell. (author)

  15. Endoscopic endonasal repair of spontaneous sphenoid sinus lateral wall meningocele presenting with cerebrospinal fluid leak

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    Ali Erdem Yildirim

    2014-01-01

    Full Text Available Spontaneous sphenoid sinus lateral wall meningoceles are rare lesions with an unknown etiology. Endoscopic endonasal technique is a considerable route in the treatment of this condition. The aim of this paper is to report the etiology, surgical technique, and outcome in a patient repaired via endoscopic endonasal approach. A 51-year-old male patient applied with rhinorrhea started three months ago after an upper respiratory infection. There were no history of trauma or sinus operation. Biochemical analysis of the fluid was positive for beta-2-transferrin. This asypthomatic patient had undergone for repairment of lateral sphenoid sinus meningocele with endoscopic endonasal transsphenoidal approach. After endoscopic endonasal meningocele closure procedure no complications occured and a quick recovery was observed. Endoscopic endonasal approach is an effective and safe treatment modality of spontaneous lateral sphenoid sinus meningoceles and efficient in anterior skull base reconstruction.

  16. Learning curve for the endoscopic endonasal approach for suprasellar craniopharyngiomas.

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    Ding, Hailin; Gu, Ye; Zhang, Xiaobiao; Xie, Tao; Liu, Tengfei; Hu, Fan; Yu, Yong; Sun, Chongjing

    2017-08-01

    The endoscopic endonasal approach is considered an alternative minimally invasive approach for suprasellar craniopharyngiomas. However, the complicated surgical manipulations required by this approach have limited its application. We evaluate whether the approach features a learning curve. Thirty-three patients were retrospectively reviewed and grouped as early (17 patients) and late (16 patient) groups. The operation time, extent of removal, ophthalmology, endocrinology, reconstruction and modifications of standard technique were evaluated. Between the two groups, the operation time decreased from 201.1±105.3min in the early group to 107.6±90.0min in the late group (pgroups. With respect to complications, non-statistically significant decreasing trends toward transient cranial nerve paralysis (from 5.9% to 0%) and non-statistically significant increasing trends toward rate of CSF leakage, meningitis and new hypothyroidism (from 11.8% to 25%, 11.8% to 31.3%, 0 to 3%) were observed. We identified a learning curve for the endoscopic endonasal approach for suprasellar craniopharyngiomas. The exact number of patients necessary to establish a significant improvement in the clinical outcomes and decrease in the complications warrants further investigation. The outcomes of tumor recurrence may be associated with duration of follow-up. The CSF leakage represented the most common complication. Copyright © 2017 Elsevier Ltd. All rights reserved.

  17. Intraoperative Neurophysiological Monitoring for Endoscopic Endonasal Approaches to the Skull Base: A Technical Guide

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    Harminder Singh

    2016-01-01

    Full Text Available Intraoperative neurophysiological monitoring during endoscopic, endonasal approaches to the skull base is both feasible and safe. Numerous reports have recently emerged from the literature evaluating the efficacy of different neuromonitoring tests during endonasal procedures, making them relatively well-studied. The authors report on a comprehensive, multimodality approach to monitoring the functional integrity of at risk nervous system structures, including the cerebral cortex, brainstem, cranial nerves, corticospinal tract, corticobulbar tract, and the thalamocortical somatosensory system during endonasal surgery of the skull base. The modalities employed include electroencephalography, somatosensory evoked potentials, free-running and electrically triggered electromyography, transcranial electric motor evoked potentials, and auditory evoked potentials. Methodological considerations as well as benefits and limitations are discussed. The authors argue that, while individual modalities have their limitations, multimodality neuromonitoring provides a real-time, comprehensive assessment of nervous system function and allows for safer, more aggressive management of skull base tumors via the endonasal route.

  18. Volumetric Analysis of Nasopharyngectomy via Endoscopic Endonasal, Maxillary Transposition, and Lateral Temporal-Subtemporal Approaches.

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    Kapucu, Burak; Gun, Ramazan; Kirsch, Claudia; Meeks, Darlene; Otto, Bradley A; Prevedello, Daniel M; Carrau, Ricardo

    2015-10-01

    This project develops a computer model that allows volumetric analysis of the exposure afforded by an endonasal-endoscopic approach, maxillary transposition, and lateral temporal-subtemporal approaches during a nasopharyngectomy. The model will demonstrate idiosyncracies of these approaches, including sacrifice of normal tissues, ease of instrumentation, and gate of entry. Computed tomographic scans of an anatomic specimen were used to create computer simulations of the endoscopic endonasal, maxillary transposition, and lateral temporal-subtemporal approaches for T1and T4 nasopharyngeal carcinoma; therefore, allowing assessment of their surgical corridor using Intuition, a software that allows a semiautomated computerized segmented volumetric analysis. The smallest volumes of tissue mobilization or removal were observed during the endoscopic-endonasal nasopharyngectomy. The volumes of tissue mobilization for the maxillary transposition approach were higher than those of lateral temporal-subtemporal approaches. This model adds to our understanding of select surgical corridors to the nasopharynx. It suggests that an endoscopic-endonasal approach requires less manipulation or resection of smaller volumes of normal tissue to expose a nasopharyngeal tumor than the lateral temporal-subtemporal and maxillary transposition approaches. It also, however, requires instrumentation through a smaller entry gate implying greater difficulty. Nonetheless, these factors should not be construed as superiority of one approach over the other. Factors that are important in the choosing of the surgical approach, such as surgeon's training and experience, invasion of neurovascular structures and method of reconstruction are not considered in this model.

  19. Combined transnasal and transoral endoscopic approach to a transsphenoidal encephalocele in an infant.

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    Tan, Sien Hui; Mun, Kein Seong; Chandran, Patricia Ann; Manuel, Anura Michelle; Prepageran, Narayanan; Waran, Vicknes; Ganesan, Dharmendra

    2015-07-01

    This paper reports an unusual case of a transsphenoidal encephalocele and discusses our experience with a minimally invasive management. To the best of our knowledge, we present the first case of a combined endoscopic transnasal and transoral approach to a transsphenoidal encephalocele in an infant. A 17-day-old boy, who was referred for further assessment of upper airway obstruction, presented with respiratory distress and feeding difficulties. Bronchoscopy and imaging revealed a transsphenoidal encephalocele. At the age of 48 days, he underwent a combined endoscopic transnasal and transoral excision of the nasal component of the encephalocele. This approach, with the aid of neuronavigation, allows good demarcation of the extra-cranial neck of the transsphenoidal encephalocele. We were able to cauterize and carefully dissect the sac prior to excision. The defect of the neck was clearly visualized, and Valsalva manoeuvre was performed to exclude any CSF leak. As the defect was small, it was allowed to heal by secondary intention. The patient's recovery was uneventful, and he tolerated full feeds orally on day 2. Postoperative imaging demonstrated no evidence of recurrence of the nasal encephalocele. Endoscopic follow-up showed good healing of the mucosa and no cerebrospinal fluid leak. The surgical management of transsphenoidal encephalocele in neonates and infants is challenging. We describe a safe technique with low morbidity in managing such a condition. The combined endoscopic transnasal and transoral approach with neuronavigation is a minimally invasive, safe and feasible alternative, even for children below 1 year of age.

  20. A case of giant ethmoidal osteoma with orbital invasion treated via endonasal endoscopic approach

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    Eda Şimşek

    2014-12-01

    Full Text Available Osteomas are the most common benign bone tumors of paranasal sinuses. In general, they are small and asymptomatic. They may lead to local symptoms such as nasal obstruction, headache and facial pain when they become large, besides more severe signs and symptoms due to orbital and cranial expansion. The treatment in symptomatic and rapidly-growing cases is surgery. In treatment of paranasal sinus osteomas, endoscopic or open surgical techniques, which may be applied according to mass dimensions and localization, are available. Endoscopic endonasal resection is a safe method with successful results and low morbidity. It causes no cosmetic problems. In this study, a giant ethmoidal sinus osteoma invading orbital wall and extending to skull base was reported. It was totally resected by endonasal endoscopic approach.

  1. Endoscopic endonasal anatomy and approaches to the anterior skull base: a neurosurgeon's viewpoint.

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    Abuzayed, Bashar; Tanriover, Necmettin; Gazioglu, Nurperi; Sanus, Galip Zihni; Ozlen, Fatma; Biceroglu, Huseyin; Kafadar, Ali Metin; Eraslan, Berna Senel; Akar, Ziya

    2010-03-01

    The objective of this study was to review the endoscopic anatomy of the anterior skull base, defining the pitfalls of endoscopic endonasal approaches to this region. Recently, these approaches are gaining popularity among neurosurgeons, and the details of the endoscopic anatomy and approaches are highlighted from the neurosurgeons' point of view, correlated with demonstrative cases. Twelve fresh adult cadavers were studied (n = 12). We used Karl Storz 0 and 30 degrees, 4 mm, 18- and 30-cm rod lens rigid endoscope in our dissections. After preparation of the cadaveric specimens, we approached the anterior skull base by the extended endoscopic endonasal approach. After resection of the superior portion of the nasal septum, bilateral middle and superior turbinates, and bilateral anterior and posterior ethmoidal cells, we could obtain full exposure of the anterior skull base. The distance between optic canal and the posterior ethmoidal artery ranged from 8 to 16 mm (mean, 11.08 mm), and the distance between posterior ethmoidal artery and the anterior ethmoidal artery ranged from 10 to 17 mm (mean, 13 mm). After resecting the anterior skull base bony structure and the dura between the 2 medial orbital walls, we could visualize the olfactory nerves, interhemispheric sulcus, and gyri recti. With dissecting the interhemispheric sulcus, we could expose the first (A1) and second (A2) segments of the anterior cerebral artery, anterior communicating artery, and Heubner arteries. This study showed that extended endoscopic endonasal approaches are sufficient in providing wide exposure of the bony structures, and the extradural and intradural components of the anterior skull base and the neighboring structures providing more controlled manipulation of pathologic lesions. These approaches need specific skill and learning curve to achieve more minimally invasive interventions and less postoperative complications.

  2. The endoscopic endonasal approach is not superior to the microscopic transcranial approach for anterior skull base meningiomas-a meta-analysis.

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    Muskens, Ivo S; Briceno, Vanessa; Ouwehand, Tom L; Castlen, Joseph P; Gormley, William B; Aglio, Linda S; Zamanipoor Najafabadi, Amir H; van Furth, Wouter R; Smith, Timothy R; Mekary, Rania A; Broekman, Marike L D

    2018-01-01

    In the past decade, the endonasal transsphenoidal approach (eTSA) has become an alternative to the microsurgical transcranial approach (mTCA) for tuberculum sellae meningiomas (TSMs) and olfactory groove meningiomas (OGMs). The aim of this meta-analysis was to evaluate which approach offered the best surgical outcomes. A systematic review of the literature from 2004 and meta-analysis were conducted in accordance with the PRISMA guidelines. Pooled incidence was calculated for gross total resection (GTR), visual improvement, cerebrospinal fluid (CSF) leak, intraoperative arterial injury, and mortality, comparing eTSA and mTCA, with p-interaction values. Of 1684 studies, 64 case series were included in the meta-analysis. Using the fixed-effects model, the GTR rate was significantly higher among mTCA patients for OGM (eTSA: 70.9% vs. mTCA: 88.5%, p-interaction OGM (p-interaction = 0.33). CSF leak was significantly higher among eTSA patients for both OGM (eTSA: 25.1% vs. mTCA: 10.5%, p-interaction OGM resection (p-interaction = 0.10). Mortality was not significantly different between eTSA and mTCA patients for both TSM (p-interaction = 0.14) and OGM resection (p-interaction = 0.88). Random-effect models yielded similar results. In this meta-analysis, eTSA was not shown to be superior to mTCA for resection of both OGMs and TSMs.

  3. Efficacy of ultra-short single agent regimen antibiotic chemo-prophylaxis in reducing the risk of meningitis in patients undergoing endoscopic endonasal transsphenoidal surgery.

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    Somma, Teresa; Maraolo, Alberto Enrico; Esposito, Felice; Cavallo, Luigi Maria; Tosone, Grazia; Orlando, Raffaele; Cappabianca, Paolo

    2015-12-01

    The study aims to evaluate the incidence of infectious complications (namely meningitis) within 30 days after endoscopic endonasal transspheinodal neurosurgery (EETS) in patients receiving an ultra-short peri-operative chemo-prophylaxis regimen with 2 doses of 1st generation cephalosporin or macrolide. We retrospectively analyzed the clinical records of 145 patients who received an ultra-short chemoprophylaxis with two doses of an antibiotic, given 30 min before and 8h after EETS, over a 30-month time-frame. Ninety-seven patients (66.89%) received endovenous cefazolin, a 1st generation cephalosporin, administered at a dosage of 1000 mg, and 48 patients (33.10%) with an history of allergy to various agents, received endovenous clarithromycin at a dosage of 500 mg. No case of peri- and post-operative meningitis occurred in patients receiving the 2 doses of antibiotic. Only one patient (0.68%) developed cerebral fluid leakage on the 7th postoperative day, which required the switching to a broad-spectrum antibiotic prophylaxis for one week; this patient received the ultrashort prophylaxis with a macrolide. In addition, 7 patients (4.82%) developed minor infectious complications such as low-grade fever (3 cases, all of them receiving cefazolin), enlarged submandibular and cervical lymphnodes (3 cases, all of them receiving cefazolin), and upper and lower respiratory tract infection (1 case receiving clarithromycin). The cost of this prophylaxis regimen ranged from 7.76 Euro (cefazolin) to 39.54 Euro (clarithromycin). This study suggested that an ultra-short single-antibiotic prophylaxis is a safe, cheap and effective regimen to prevent post-operative meningitis in patients undergoing EETS and who do not require lumbar drainage after surgery. In these patients also the rate of minor infective complications was acceptable when compared with the previous more expensive regimen based on 3rd generation cephalosporin plus aminoglycoside or alone, that could be suitable only

  4. Extended Endoscopic Endonasal Approaches for Cerebral Aneurysms: Anatomical, Virtual Reality and Morphometric Study

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    de Notaris, Matteo; Enseñat, Joaquim; Alobid, Isam; San Molina, Joan; Berenguer, Joan; Cappabianca, Paolo

    2014-01-01

    Introduction. The purpose of the present contribution is to perform a detailed anatomic and virtual reality three-dimensional stereoscopic study in order to test the effectiveness of the extended endoscopic endonasal approaches for selected anterior and posterior circulation aneurysms. Methods. The study was divided in two main steps: (1) simulation step, using a dedicated Virtual Reality System (Dextroscope, Volume Interactions); (2) dissection step, in which the feasibility to reach specific vascular territory via the nose was verified in the anatomical laboratory. Results. Good visualization and proximal and distal vascular control of the main midline anterior and posterior circulation territory were achieved during the simulation step as well as in the dissection step (anterior communicating complex, internal carotid, ophthalmic, superior hypophyseal, posterior cerebral and posterior communicating, basilar, superior cerebellar, anterior inferior cerebellar, vertebral, and posterior inferior cerebellar arteries). Conclusion. The present contribution is intended as strictly anatomic study in which we highlighted some specific anterior and posterior circulation aneurysms that can be reached via the nose. For clinical applications of these approaches, some relevant complications, mainly related to the endonasal route, such as proximal and distal vascular control, major arterial bleeding, postoperative cerebrospinal fluid leak, and olfactory disturbances must be considered. PMID:24575410

  5. Extended Endoscopic Endonasal Approaches for Cerebral Aneurysms: Anatomical, Virtual Reality and Morphometric Study

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    Alberto Di Somma

    2014-01-01

    Full Text Available Introduction. The purpose of the present contribution is to perform a detailed anatomic and virtual reality three-dimensional stereoscopic study in order to test the effectiveness of the extended endoscopic endonasal approaches for selected anterior and posterior circulation aneurysms. Methods. The study was divided in two main steps: (1 simulation step, using a dedicated Virtual Reality System (Dextroscope, Volume Interactions; (2 dissection step, in which the feasibility to reach specific vascular territory via the nose was verified in the anatomical laboratory. Results. Good visualization and proximal and distal vascular control of the main midline anterior and posterior circulation territory were achieved during the simulation step as well as in the dissection step (anterior communicating complex, internal carotid, ophthalmic, superior hypophyseal, posterior cerebral and posterior communicating, basilar, superior cerebellar, anterior inferior cerebellar, vertebral, and posterior inferior cerebellar arteries. Conclusion. The present contribution is intended as strictly anatomic study in which we highlighted some specific anterior and posterior circulation aneurysms that can be reached via the nose. For clinical applications of these approaches, some relevant complications, mainly related to the endonasal route, such as proximal and distal vascular control, major arterial bleeding, postoperative cerebrospinal fluid leak, and olfactory disturbances must be considered.

  6. Ectopic pituitary null cell adenoma arising from the infundibulum in the third ventricle: A successful endonasal transsphenoidal resection after long-term follow-up MR imaging – A technical note

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    Yuichiro Yoneoka, M.D., Ph.D.

    2017-12-01

    Conclusion: To our best knowledge, this is the first case with long-term preoperative follow-up images, which can bridge the knowledge gap in operations of third ventricle ectPA as following: (1 Truly third ventricle ectPA can exist, (2 the third ventricle ectPA extended into the sella turcica along the pituitary stalk, (3 this ectPA can arise from the suprasellar peri-infundibular ectopic pituitary cells or the pars tuberalis of the adenohypophysis, and therefore adhere to the optic chiasm, (4 thus neurosurgeons should take great care in resection of ectPA arising from the infundibulum, and (5 it can be resected through an endoscopic extended transsphenoidal approach.

  7. Surgical resection of pituitary adenoma via neuroendoscopic single-nostril transsphenoidal approach: a clinical analysis

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    Gang-ge CHENG

    2015-06-01

    Full Text Available Objective To explore the technique and clinical efficacy of single-nostril transsphenoidal neuroendoscopic resection of pituitary adenomas. Methods A total of 47 patients with pituitary adenoma, among them 21 were male and 26 female, aged 15-70 years old with a mean of 42.7 years, were treated with neuroendoscopic single-nostril transsphenoidal surgical resection in the Air Force General Hospital of PLA from August 2007 to August 2013. Clinical data were analyzed retrospectively, including the operative results, complications, and follow up results. Results Post-operative MRI revealed that the tumor was totally removed in 38 (80.9% patients, and subtotally in 9 (19.1%, the tumors were large and had invaded the cavernous sinus. Post-operative improvement of clinical symptoms was achieved in 40 (85.1% patients, among them, headache disappeared in 35 patients, vision and visual field improved in 30 patients. Among the 47 patients, an increase in prolactin hormone (PRH type was seen in 29, an increase in growth hormone (GH type in 6, and non-functioning pituitary carcinoma in 12 patients. In 80% (28/36 of the patients hormone secretion was improved after the operation, including 23 of PRH type and 5 of GH type. Post-operative complications were diabetes insipidus in 10 patients, cerebrospinal fluid leakage in 8 and meningitis in one. All the patients were followed up for 6 months up to 6 years, and no death occurred. Conclusion Single-nostril transsphenoidal endoscopic surgery consists of many advantages, such as minimal trauma, clear visual field, higher total resection rate, and rapid recovery after operation, therefore it is a safe and effective approach for the resection of pituitary adenomas. DOI: 10.11855/j.issn.0577-7405.2015.05.15

  8. Limitations of the endonasal endoscopic approach in treating olfactory groove meningiomas. A systematic review.

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    Shetty, Sathwik Raviraj; Ruiz-Treviño, Armando S; Omay, Sacit Bulent; Almeida, Joao Paulo; Liang, Buqing; Chen, Yu-Ning; Singh, Harminder; Schwartz, Theodore H

    2017-10-01

    To review current management strategies for olfactory groove meningioma (OGM)s and the recent literature comparing endoscopic endonasal (EEA) with traditional transcranial (TCA) approaches. A PubMed search of the recent literature (2011-2016) was performed to examine outcomes following EEA and TCA for OGM. The extent of resection, visual outcome, postoperative complications and recurrence rates were analyzed using percentages and proportions, the Fischer exact test and the Student's t-test using Graphpad PRISM 7.0Aa (San Diego, CA) software. There were 444 patients in the TCA group with a mean diameter of 4.61 (±1.17) cm and 101 patients in the EEA group with a mean diameter of 3.55 (± 0.58) cm (p = 0.0589). GTR was achieved in 90.9% (404/444) in the TCA group and 70.2% (71/101) in the EEA group (p OGMs.

  9. The Usefulness of the Endonasal Incisional Approach for the Treatment of Nasal Bone Fracture

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    Hyo Seong Kim

    2012-05-01

    Full Text Available BackgroundAmong all facial fractures, nasal bone fractures are the most common, and they have been reduced by closed reduction (CR for a long time. But several authors have reported suboptimal results when using CR, and the best method of nasal bone reduction is still being debated. We have found that indirect open reduction (IOR through an endonasal incisional approach is a useful method for more accurate reduction of the nasal bone.MethodsA retrospective chart review was performed of 356 patients who underwent reduction of a nasal bone fracture in our department from January, 2006, to July, 2011. We treated 263 patients with IOR. We assessed patients' and doctors' satisfaction with surgical outcomes after IOR or CR. We evaluated the frequency of nasal bleeding owing to mucosal injury, and followed the surgical outcomes of patients who had simultaneous dorsal augmentation rhinoplasty.ResultsAccording to the analysis of the satisfaction scores, both patients and doctors were significantly more satisfied in the IOR group than the CR group (P<0.05. Mucosal injury with nasal bleeding occurred much less in the IOR group (5.3% than the CR group (12.9%. Dorsal augmentation rhinoplasty with IOR was performed simultaneously in 34 cases. Most of them (31/34 showed satisfaction with the outcomes.ConclusionsIOR enables surgeons to manipulate the bony fragment directly through the endonasal incisional approach. However, we propose that CR is the proper technique for patients under 16 and for those with comminuted nasal bone fractures because submucosal dissection in IOR can damage the growth or circulation of nasal bone.

  10. Evolution of transoral approaches, endoscopic endonasal approaches, and reduction strategies for treatment of craniovertebral junction pathology: a treatment algorithm update.

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    Dlouhy, Brian J; Dahdaleh, Nader S; Menezes, Arnold H

    2015-04-01

    The craniovertebral junction (CVJ), or the craniocervical junction (CCJ) as it is otherwise known, houses the crossroads of the CNS and is composed of the occipital bone that surrounds the foramen magnum, the atlas vertebrae, the axis vertebrae, and their associated ligaments and musculature. The musculoskeletal organization of the CVJ is unique and complex, resulting in a wide range of congenital, developmental, and acquired pathology. The refinements of the transoral approach to the CVJ by the senior author (A.H.M.) in the late 1970s revolutionized the treatment of CVJ pathology. At the same time, a physiological approach to CVJ management was adopted at the University of Iowa Hospitals and Clinics in 1977 based on the stability and motion dynamics of the CVJ and the site of encroachment, incorporating the transoral approach for irreducible ventral CVJ pathology. Since then, approaches and techniques to treat ventral CVJ lesions have evolved. In the last 40 years at University of Iowa Hospitals and Clinics, multiple approaches to the CVJ have evolved and a better understanding of CVJ pathology has been established. In addition, new reduction strategies that have diminished the need to perform ventral decompressive approaches have been developed and implemented. In this era of surgical subspecialization, to properly treat complex CVJ pathology, the CVJ specialist must be trained in skull base transoral and endoscopic endonasal approaches, pediatric and adult CVJ spine surgery, and must understand and be able to treat the complex CSF dynamics present in CVJ pathology to provide the appropriate, optimal, and tailored treatment strategy for each individual patient, both child and adult. This is a comprehensive review of the history and evolution of the transoral approaches, extended transoral approaches, endoscopie assisted transoral approaches, endoscopie endonasal approaches, and CVJ reduction strategies. Incorporating these advancements, the authors update the

  11. Outcomes following Purely Endoscopic Endonasal Resection of Pituitary adenomas

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    Rezaul Amin

    2013-01-01

    Full Text Available Background: The use of endoscope for the management of pituitary adenoma is not new. The better magnification and illumination provided by the endoscope gives better outcome than microscopic pituitary surgery. Objective: To find out the benefits of endoscope in relation to microscopic surgery. Materials and Methods: We performed 45 cases of pituitary adenoma surgery by endoscopic endonasal approach from July 2008 to July 2010. Results: Forty five cases underwent endoscopic transsphenoidal approach. Gross total removal was done in 35 cases and subtotal removal was done in 10 cases. Residual tumours were seen in 10 cases (22% in postoperative follow-up MRI scan. Visual improvement was satisfactory, and hormonal improvement of functional adenoma was nice. Postoperative visual acuity and visual field were improved in 75% cases. There were 37% cases of temporary diabetes insipidus and about 4.5% cases of permanent diabetes insipidus. The average duration of follow-up was 20 months. One patient required reexploration to correct visual deterioration in the immediate postoperative period. There were 4.5% cases of CSF leak and 6.6% mortality. Mortality was due to electrolyte imbalance and improper management of infection and hydrocephalus. Conclusion: Endoscopic endonasal pituitary surgery now has become a gold standard surgery for most of the pituitary adenomas because of its better advantages in relation to microscopic surgery and less complications and less hospital stay.

  12. Supraorbital Versus Endoscopic Endonasal Approaches for Olfactory Groove Meningiomas: A Cost-Minimization Study.

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    Gandhoke, Gurpreet S; Pease, Matthew; Smith, Kenneth J; Sekula, Raymond F

    2017-09-01

    To perform a cost-minimization study comparing the supraorbital and endoscopic endonasal (EEA) approach with or without craniotomy for the resection of olfactory groove meningiomas (OGMs). We built a decision tree using probabilities of gross total resection (GTR) and cerebrospinal fluid (CSF) leak rates with the supraorbital approach versus EEA with and without additional craniotomy. The cost (not charge or reimbursement) at each "stem" of this decision tree for both surgical options was obtained from our hospital's finance department. After a base case calculation, we applied plausible ranges to all parameters and carried out multiple 1-way sensitivity analyses. Probabilistic sensitivity analyses confirmed our results. The probabilities of GTR (0.8) and CSF leak (0.2) for the supraorbital craniotomy were obtained from our series of 5 patients who underwent a supraorbital approach for the resection of an OGM. The mean tumor volume was 54.6 cm 3 (range, 17-94.2 cm 3 ). Literature-reported rates of GTR (0.6) and CSF leak (0.3) with EEA were applied to our economic analysis. Supraorbital craniotomy was the preferred strategy, with an expected value of $29,423, compared with an EEA cost of $83,838. On multiple 1-way sensitivity analyses, supraorbital craniotomy remained the preferred strategy, with a minimum cost savings of $46,000 and a maximum savings of $64,000. Probabilistic sensitivity analysis found the lowest cost difference between the 2 surgical options to be $37,431. Compared with EEA, supraorbital craniotomy provides substantial cost savings in the treatment of OGMs. Given the potential differences in effectiveness between approaches, a cost-effectiveness analysis should be undertaken. Copyright © 2017 Elsevier Inc. All rights reserved.

  13. Pure endoscopic expanded endonasal approach for olfactory groove and tuberculum sellae meningiomas.

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    Khan, Osaama H; Krischek, Boris; Holliman, Damian; Klironomos, George; Kucharczyk, Walter; Vescan, Allan; Gentili, Fred; Zadeh, Gelareh

    2014-06-01

    The expanded endoscopic endonasal (EEE) approach for the removal of olfactory groove (OGM) and tuberculum sellae (TSM) meningiomas is currently becoming an acceptable surgical approach in neurosurgical practice, although it is still controversial with respect to its outcomes, indications and limitations. Here we provide a review of the available literature reporting results with use of the EEE approach for these lesions together with our experience with the use of the endoscope as the sole means of visualization in a series of patients with no prior surgical biopsy or resection. Surgical cases between May 2006 and January 2013 were retrospectively reviewed. Twenty-three patients (OGM n=6; TSM n=17) were identified. In our series gross total resection (GTR) was achieved in 4/6 OGM (66.7%) and 11/17 (64.7%) TSM patients. Vision improved in the OGM group (2/2) and 8/11 improved in the TSM group with no change in visual status in the remaining three patients. Post-operative cerebrospinal fluid (CSF) leak occurred in 2/6 (33%) OGM and 2/17 (11.8%) TSM patients. The literature review revealed a total of 19 OGM and 174 TSM cases which were reviewed. GTR rate was 73% for OGM and 56.3% for TSM. Post-operative CSF leak was 30% for OGM and 14% for TSM. With careful patient selection and a clear understanding of its limitations, the EEE technique is both feasible and safe. However, longer follow-ups are necessary to better define the appropriate indications and ideal patient population that will benefit from the use of these newer techniques. Crown Copyright © 2013. Published by Elsevier Ltd. All rights reserved.

  14. Endoscopic Endonasal Transclival Approach for Resection of a Pontine Glioma: Surgical Planning, Surgical Anatomy, and Technique.

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    Fernandes Cabral, David T; Zenonos, Georgios A; Nuñez, Maximiliano; Celtikci, Pinar; Snyderman, Carl; Wang, Eric; Gardner, Paul A; Fernandez-Miranda, Juan C

    2018-03-12

    The endoscopic endonasal approach (EEA) has been proposed as a potential alternative for ventral brainstem lesions. The surgical anatomy, feasibility, and limitations of the EEA for intrinsic brainstem lesions are still poorly understood. To describe the surgical planning, anatomy, and technique of an intrinsic pontine glioma operated via EEA. Six-human brainstems were prepared for white matter microdissection. Ten healthy subjects were studied with high-definition fiber tractography (HDFT). A 56-yr-old female with right-hemiparesis underwent EEA for an exophytic pontine glioma. Pre- and postoperative HDFTs were implemented. The corticospinal tracts (CSTs) are the most eloquent fibers in the ventral brainstem. At the pons, CSTs run between the pontine nuclei and the middle cerebellar peduncle (MCP). At the lower medulla, the pyramidal decussation leaves no room for safe ventral access. In our illustrative case, preoperative HDFT showed left-CST displaced posteromedially and partially disrupted, right-CST posteriorly displaced, and MCP severely disrupted. A transclival exposure was performed achieving a complete resection of the exophytic component with residual intra-axial tumor. Immediately postop, patient developed new left-side abducens nerve palsy and worse right-hemiparesis. Ten days postop, her strength returned to baseline. HDFT showed preservation and trajectory restoration of the CSTs. The EEA provides direct access to the ventral brainstem, overcoming the limitations of lateral approaches. For intrinsic pathology, HDFT helps choosing the most appropriate surgical route/boundaries for safer resection. Further experience is needed to determine the indications and limitations of this approach that should be performed by neurosurgeons with high-level expertise in EEA.

  15. [Endonasal skull base endoscopy].

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    Simal-Julián, Juan Antonio; Miranda-Lloret, Pablo; Pancucci, Giovanni; Evangelista-Zamora, Rocío; Pérez-Borredá, Pedro; Sanromán-Álvarez, Pablo; Perez-de-Sanromán, Laila; Botella-Asunción, Carlos

    2013-01-01

    The endoscopic endonasal techniques used in skull base surgery have evolved greatly in recent years. Our study objective was to perform a qualitative systematic review of the likewise systematic reviews in published English language literature, to examine the evidence and conclusions reached in these studies comparing transcranial and endoscopic approaches in skull base surgery. We searched the references on the MEDLINE and EMBASE electronic databases selecting the systematic reviews, meta-analyses and evidence based medicine reviews on skull based pathologies published from January 2000 until January 2013. We focused on endoscopic impact and on microsurgical and endoscopic technique comparisons. Full endoscopic endonasal approaches achieved gross total removal rates of craniopharyngiomas and chordomas higher than those for transcranial approaches. In anterior skull base meningiomas, complete resections were more frequently achieved after transcranial approaches, with a trend in favour of endoscopy with respect to visual prognosis. Endoscopic endonasal approaches minimised the postoperative complications after the treatment of cerebrospinal fluid (CSF) leaks, encephaloceles, meningoceles, craniopharyngiomas and chordomas, with the exception of postoperative CSF leaks. Randomized multicenter studies are necessary to resolve the controversy over endoscopic and microsurgical approaches in skull base surgery. Copyright © 2013 Sociedad Española de Neurocirugía. Published by Elsevier España. All rights reserved.

  16. Assessment of the Endoscopic Endonasal Transclival Approach for Surgical Clipping of Anterior Pontine Anterior-Inferior Cerebellar Artery Aneurysms.

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    Sanmillan, Jose L; Lawton, Michael T; Rincon-Torroella, Jordina; El-Sayed, Ivan H; Zhang, Xin; Meybodi, Ali Tayebi; Gabarros, Andreu; Benet, Arnau

    2016-05-01

    Aneurysms of the anterior pontine segment of the anterior-inferior cerebellar artery (AICA) are uncommon. Their treatment is challenging because critical neurovascular structures are adjacent to it and the available surgical corridors are narrow and deep. Although endoscopic endonasal approaches are accepted for treating midline skull base lesions, their role in the treatment vascular lesions remains undefined. The present study is aimed to assess the anatomic feasibility of the endoscopic endonasal transclival (EET) approach for treating anterior pontine AICA aneurysms and compare it with the subtemporal anterior transpetrosal (SAT) approach. Twelve cadaveric specimens were prepared for surgical simulation. The AICAs were exposed using both EET and SAT approaches. Surgical window area and the length of the exposed artery were measured. The distance from the origin of the artery to the clip applied for proximal control was measured. The number of AICA perforators exposed and the anatomic features of each AICA were recorded. The EET approach provided a wider surgical window area compared with the SAT (P AICA perforators were visualized using the EET approach (P AICA, an aneurysm clip could be applied closer to the origin of AICA using EET (0.2 ± 0.42 mm) compared with SAT (6.26 ± 3.4 mm) (P AICA aneurysms using the EET approach is feasible. Compared with SAT, the EET approach provides advantages in surgical window area, ensuring proximal control before aneurysm dissection, visualization of perforating branches, and better proximal control. Copyright © 2016 Elsevier Inc. All rights reserved.

  17. A panoramic view of the skull base: systematic review of open and endoscopic endonasal approaches to four tumors.

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    Graffeo, Christopher S; Dietrich, August R; Grobelny, Bartosz; Zhang, Meng; Goldberg, Judith D; Golfinos, John G; Lebowitz, Richard; Kleinberg, David; Placantonakis, Dimitris G

    2014-08-01

    Endoscopic endonasal surgery has been established as the safest approach to pituitary tumors, yet its role in other common skull base lesions has not been established. To answer this question, we carried out a systematic review of reported series of open and endoscopic endonasal approaches to four major skull base tumors: olfactory groove meningiomas (OGM), tuberculum sellae meningiomas (TSM), craniopharyngiomas (CRA), and clival chordomas (CHO). Data from 162 studies containing 5,701 patients were combined and compared for differences in perioperative mortality, gross total resection (GTR), cerebrospinal fluid (CSF) leak, neurological morbidity, post-operative visual function, post-operative anosmia, post-operative diabetes insipidus (DI), and post-operative obesity/hyperphagia. Weighted average rates for each outcome were calculated using relative study size. Our findings indicate similar rates of GTR and perioperative mortality between open and endoscopic approaches for all tumor types. CSF leak was increased after endoscopic surgery. Visual function symptoms were more likely to improve after endoscopic surgery for TSM, CRA, and CHO. Post-operative DI and obesity/hyperphagia were significantly increased after open resection in CRA. Recurrence rates per 1,000 patient-years of follow-up were higher in endoscopy for OGM, TSM, and CHO. Trends for open and endoscopic surgery suggested modest improvement in all outcomes over time. Our observations suggest that endonasal endoscopy is a safe alternative to craniotomy and may be preferred for certain tumor types. However, endoscopic surgery is associated with higher rates of CSF leak, and possibly increased recurrence rates. Prospective study with long-term follow-up is required to verify these preliminary observations.

  18. Endoscopic treatment of trans-sellar trans-sphenoidal encephalocele associated with morning glory syndrome presenting with non-traumatic cerebrospinal fluid rhinorrhea.

    Science.gov (United States)

    Sasani, M; Ozer, A F; Aydin, A L

    2009-03-01

    Basal encephaloceles are rare, accounting for about 1.5% of all encephaloceles. The trans-sellar trans-sphenoidal encephalocele variety is the rarest. Morning glory syndrome is often associated with basal encephalocele. Spontaneous cerebrospinal fluid (CSF) rhinorrheas are the least common of these, accounting for only 3% to 5% of all CSF rhinorrheas. The authors describe the outcome of a 10-year follow-up study of a 26-year-old male patient with a spontaneous CSF rhinorrhea occurring trans-sphenoidal encephalocele associated with bilateral morning glory syndrome that was treated with an endoscopic endonasal approach. Endoscopic exploration of the sella floor was performed and closed with abdomen fat packing and muscle fascia. The postoperative course was uneventful. A follow-up magnetic resonance (MR) image at 6 months postoperatively showed extension of encephalocele in the sphenoidal sinus, which was repaired. The patient had no further CSF rhinorrhea and showed no ophthalmologic changes over a follow-up period of over 10 years. Ophthalmologic findings such as strabismus, in association with anomalies of the optic nerve, should alert the physician to the possible presence of an unrecognized skull base midline defect and encephalocele before CSF leakage is seen. The authors believe that a surgeon who has equal confidence in performing the endoscopic endonasal and conventional microscopic trans-sphenoidal approaches should choose the less invasive surgery.

  19. A road map to the internal carotid artery in expanded endoscopic endonasal approaches to the ventral cranial base.

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    Labib, Mohamed A; Prevedello, Daniel M; Carrau, Ricardo; Kerr, Edward E; Naudy, Cristian; Abou Al-Shaar, Hussam; Corsten, Martin; Kassam, Amin

    2014-09-01

    Injuring the internal carotid artery (ICA) is a feared complication of endoscopic endonasal approaches. To introduce a comprehensive ICA classification scheme pertinent to safe endoscopic endonasal cranial base surgery. Anatomic dissections were performed in 33 cadaveric specimens (bilateral). Anatomic correlations were analyzed. Based on anatomic correlations, the ICA may be described as 6 distinct segments: (1) parapharyngeal (common carotid bifurcation to ICA foramen); (2) petrous (carotid canal to posterolateral aspect of foramen lacerum); (3) paraclival (posterolateral foramen lacerum to the superomedial aspect of the petrous apex); (4) parasellar (superomedial petrous apex to the proximal dural ring); (5) paraclinoid (from the proximal to the distal dural rings); and (6) intradural (distal ring to ICA bifurcation). Corresponding surgical landmarks included the Eustachian tube, the fossa of Rosenmüller, and levator veli palatini for the parapharyngeal segment; the vidian canal and V3 for the petrous segment; the fibrocartilage of foramen lacerum, foramen rotundum, maxillary strut, lingular process of the sphenoid bone, and paraclival protuberance for the paraclival segment; the sellar floor and petrous apex for the parasellar segment; and the medial and lateral opticocarotid and lateral tubercular recesses, as well as the distal osseous arch of the carotid sulcus for the paraclinoid segment. The proposed endoscopic classification outlines key anatomic reference points independent of the vessel's geometry or the sinonasal pneumatization, thus serving as (1) a practical guide to navigate the ventral cranial base while avoiding injury to the ICA and (2) further foundation for a modular access system.

  20. Risk factors for postoperative cerebrospinal fluid leak and meningitis after expanded endoscopic endonasal surgery.

    Science.gov (United States)

    Ivan, Michael E; Iorgulescu, J Bryan; El-Sayed, Ivan; McDermott, Michael W; Parsa, Andrew T; Pletcher, Steven D; Jahangiri, Arman; Wagner, Jeffrey; Aghi, Manish K

    2015-01-01

    Postoperative cerebrospinal fluid (CSF) leak is a serious complication of transsphenoidal surgery, which can lead to meningitis and often requires reparative surgery. We sought to identify preoperative risk factors for CSF leaks and meningitis. We reviewed 98 consecutive expanded endoscopic endonasal surgeries performed from 2008-2012 and analyzed preoperative comorbidities, intraoperative techniques, and postoperative care. Univariate and multivariate analyses were performed. The most common pathologies addressed included pituitary adenoma, Rathke cyst, chordoma, esthesioneuroblastoma, meningioma, nasopharyngeal carcinoma, and squamous cell carcinoma. There were 11 CSF leaks (11%) and 10 central nervous system (CNS) infections (10%). Univariate and multivariate analysis of preoperative risk factors showed that patients with non-ideal body mass index (BMI) were associated with higher rate of postoperative CSF leak and meningitis (both p<0.01). Also, patients with increasing age were associated with increased CSF leak (p = 0.03) and the length of time a lumbar drain was used postoperatively was associated with infection in a univariate analysis. In addition, three of three endoscopic transsphenoidal surgeries combined with open cranial surgery had a postoperative CSF leak and CNS infection rate which was a considerably higher rate than for transsphenoidal surgeries alone or surgeries staged with open cases (p<0.01 and p=0.04, respectively) In this series of expanded endoscopic transsphenoidal surgeries, preoperative BMI remains the most important preoperative predictor for CSF leak and infection. Other risk factors include age, intraoperative CSF leak, lumbar drain duration, and cranial combined cases. Risks associated with complex surgical resections when combining open and endoscopic approaches could be minimized by staging these procedures. Copyright © 2014 Elsevier Ltd. All rights reserved.

  1. Endoscopic endonasal approach for the treatment of a large clival giant cell tumor complicated by an intraoperative internal carotid artery rupture

    Directory of Open Access Journals (Sweden)

    Iacoangeli M

    2013-01-01

    Full Text Available Maurizio Iacoangeli,1 Alessandro Di Rienzo,1 Massimo Re,2 Lorenzo Alvaro,1 Niccolò Nocchi,1 Maurizio Gladi,1 Maurizio De Nicola,3 Massimo Scerrati11Department of Neurosurgery, Università Politecnica delle Marche, Umberto I General Hospital, Ancona, Italy; 2Department of Ear, Nose, and Throat Surgery, Università Politecnica delle Marche, Umberto I General Hospital, Ancona, Italy; 3Department of Radiology, Interventional Radiology Section, Università Politecnica delle Marche, Umberto I General Hospital, Ancona, ItalyAbstract: Giant cell tumors (GCTs are primary bone neoplasms that rarely involve the skull base. These lesions are usually locally aggressive and require complete removal, including the surrounding apparently healthy bone, to provide the best chance of cure. GCTs, as well as other lesions located in the clivus, can nowadays be treated by a minimally invasive fully endoscopic extended endonasal approach. This approach ensures a more direct route to the craniovertebral junction than other possible approaches (transfacial, extended lateral, and posterolateral approaches. The case reported is a clival GCT operated on by an extended endonasal approach that provides another contribution on how to address one of the most feared complications attributed to this approach: a massive bleed due to an internal carotid artery injury.Keywords: clival giant cell tumor, endoscopic endonasal approach, internal carotid artery injury, minimally invasive surgery

  2. Endoscopic endonasal surgery for giant pituitary adenomas: advantages and limitations.

    Science.gov (United States)

    Koutourousiou, Maria; Gardner, Paul A; Fernandez-Miranda, Juan C; Paluzzi, Alessandro; Wang, Eric W; Snyderman, Carl H

    2013-03-01

    Giant pituitary adenomas (> 4 cm in maximum diameter) represent a significant surgical challenge. Endoscopic endonasal surgery (EES) has recently been introduced as a treatment option for these tumors. The authors present the results of EES for giant adenomas and analyze the advantages and limitations of this technique. The authors retrospectively reviewed the medical files and imaging studies of 54 patients with giant pituitary adenomas who underwent EES and studied the factors affecting surgical outcome. Preoperative visual impairment was present in 45 patients (83%) and partial or complete pituitary deficiency in 28 cases (52%), and 7 patients (13%) presented with apoplexy. Near-total resection (> 90%) was achieved in 36 patients (66.7%). Vision was improved or normalized in 36 cases (80%) and worsened in 2 cases due to apoplexy of residual tumor. Significant factors that limited the degree of resection were a multilobular configuration of the adenoma (p = 0.002) and extension to the middle fossa (p = 0.045). Cavernous sinus invasion, tumor size, and intraventricular or posterior fossa extension did not influence the surgical outcome. Complications included apoplexy of residual adenoma (3.7%), permanent diabetes insipidus (9.6%), new pituitary insufficiency (16.7%), and CSF leak (16.7%, which was reduced to 7.4% in recent years). Fourteen patients underwent radiation therapy after EES for residual mass or, in a later stage, for recurrence, and 10 with functional pituitary adenomas received medical treatment. During a mean follow-up of 37.9 months (range 1-114 months), 7 patients were reoperated on for tumor recurrence. Three patients were lost to follow-up. Endoscopic endonasal surgery provides effective initial management of giant pituitary adenomas with favorable results compared with traditional microscopic transsphenoidal and transcranial approaches.

  3. Safety of transsphenoidal microsurgical approach in patients with an ACTH-secreting pituitary adenoma.

    Science.gov (United States)

    Donofrio, Carmine Antonio; Losa, Marco; Gemma, Marco; Giudice, Lodoviga; Barzaghi, Lina Raffaella; Mortini, Pietro

    2017-11-01

    Patients affected by Cushing's disease often have important comorbidities directly linked to hypercortisolism that might enhance the operative risk. We report the safety of transsphenoidal surgery in patients affected by Cushing's disease as compared with patients with nonfunctioning pituitary adenoma. We have retrospectively analyzed 142 patients with Cushing's disease and 299 patients with nonfunctioning pituitary adenoma who underwent transsphenoidal surgery performed by a single experienced neurosurgeon between September 2007 and December 2014. For all of them, an intraoperative computerized anesthetic record for the automatic storage of data was available. The intraoperative vital parameters and the frequency of drugs administered during anesthesia were comparable between Cushing's disease and nonfunctioning pituitary adenoma groups. The duration of surgery was similar between the two groups (41.2 ± 11.8 vs. 42.9 ± 15.6 min), while the duration of anesthesia was slightly shorter in Cushing's disease patients (97.6 ± 18.1 min) than in nonfunctioning pituitary adenoma patients (101.6 ± 20.6 min, p = 0.04). The total perioperative mortality rate was 0.2% (0% in Cushing's disease vs. 0.3% in nonfunctioning pituitary adenoma). Cushing's disease patients had surgical and medical complication rates of 3.5% each, not different from those occurring in nonfunctioning pituitary adenoma. The postoperative incidence of diabetes insipidus (10.6%) and isolated hyponatremia (10.6%) in Cushing's disease patients was significantly higher than in nonfunctioning pituitary adenoma patients (4.4 and 4.1%; p = 0.02 and p = 0.01, respectively). In a large series of unselected and consecutive patients with Cushing's disease, transsphenoidal surgery performed by one dedicated experienced neurosurgeon had a reasonably low risk of complications. In particular, despite the higher burden of comorbidities typically associated with hypercortisolism

  4. Expanded endonasal endoscopic approach for resection of a large skull base aneurysmal bone cyst in a pediatric patient with extensive cranial fibrous dysplasia.

    Science.gov (United States)

    Salmasi, Vafi; Blitz, Ari M; Ishii, Masaru; Gallia, Gary L

    2011-04-01

    Aneurysmal bone cysts (ABCs) are uncommon non-neoplastic, hemorrhagic, and expansile osseous lesions. These lesions most commonly occur in the first two decades of life and affect the long bones and spinal column. Skull base involvement is rare. The authors report the case of a 16-year-old boy who presented with acute visual decline and was found to have a large skull base ABC centered in the sphenoid sinus. In addition, the patient had extensive cranial fibrous dysplasia. The patient underwent a staged expanded endonasal endoscopic approach for complete resection of this lesion with excellent return of his vision. This case adds to the growing body of evidence supporting a role for expanded endonasal endoscopic procedures in pediatric patients with skull base pathologies.

  5. Transsellar transsphenoidal encephalocele: a series of four cases.

    Science.gov (United States)

    Rathore, Yashpal S; Sinha, Sumit; Mahapatra, A K

    2011-01-01

    Transsellar transsphenoidal encephalocele is the least common type of basal encephalocele. We present a series of four cases of transsellar transsphenoidal encephalocele. Clinical findings, imaging reviews, surgical repair techniques and postoperative morbidity are discussed with the relevant literature. Non contrast CT scan head with 3D reconstruction and magnetic resonance imaging should be done in all patients of transsphenoidal encephalocele. Endocrine assessment is also essential. Repair of a transsphenoidal encephalocele should be coordinated between a team of neurosurgeons and ENT surgeon. Our surgical outcome supports the transpalatal/ transnasal approach over the transcranial approach.

  6. Using the Endoscopic Endonasal Transclival Approach to Access Aneurysms Arising from AICA, PICA, and Vertebral Artery: An Anatomical Study.

    Science.gov (United States)

    Doan, Vivian; Lemos-Rodriguez, Ana M; Sreenath, Satyan B; Unnithan, Ajay; Recinos, Pablo F; Zanation, Adam M; Sasaki-Adams, Deanna M

    2016-06-01

    Objective To explore the use of the endoscopic endonasal transclival approach (EEA) for clipping anterior inferior cerebellar artery (AICA), posterior inferior cerebellar artery (PICA), and vertebral artery (VA) aneurysms. Design Anatomical study. Participants Fifteen adult cadavers. Main Outcome Measures Length of artery exposed and distance from the nasal ala to the arteries. Results The length of the right and left VA exposed were 1.7 ± 0.6 cm and 1.6 ± 0.6 cm, respectively. The distance to the right VA was 11.1 ± 0.9 cm and to the left was 11.1 ± 0.8 cm. Right and left AICA were exposed for an average length of 1.1 ± 0.3 cm and 0.8 ± 0.3 cm, respectively. The distance to the right AICA was 10.3 ± 0.8 cm and to the left was 10.3 ± 0.8 cm. The right PICA was exposed for a length of 0.5 ± 0.2 cm at a distance of 10.9 ± 0.5 cm. The left PICA was exposed for a length of 0.5 ± 0.2 cm at a distance of 11.1 ± 0.9 cm. Conclusion The EEA can provide direct access to AICA, PICA, and VA, making it a potential alternative to the traditional approaches for the clipping of aneurysms arising from those arteries.

  7. Quantitative Comparison of Three Endoscopic Approaches to the Parasellar Region: Laboratory Investigation.

    Science.gov (United States)

    Belykh, Evgenii; Yağmurlu, Kaan; Hong, Yuan; Mooney, Michael A; Bozkurt, Baran; Byvaltsev, Vadim A; Nakaji, Peter; Preul, Mark C

    2017-12-01

    Endoscopic endonasal transsphenoidal and contralateral sublabial transmaxillary approaches are used for approaching parasellar lesions. The aim of this anatomical study was to compare endoscopic endonasal uninostril and binostril (contralateral) and contralateral sublabial transmaxillary approaches via a quantitative analysis of exposure limits and instrument working avenues. Six formalin-fixed silicone-injected adult cadaveric heads (12 sides) were studied. The surgical working area, depth of the surgical corridor, angle of attack, and surgical freedom were measured and compared for the 3 approaches. The endoscopic binostril endonasal approach to the parasellar area provided greater surgical freedom in the opticocarotid recess (OCR) and superior orbital fissure (SOF) compared with that of the uninostril endonasal approach (OCR, P trajectory to the contralateral parasellar area (P < 0.01). An anatomical comparison of the 3 endoscopic approaches to the parasellar area showed that the binostril approach provides greater exposure and freedom for instrument manipulation. The contralateral transmaxillary route provided a more lateral view, increasing exposure on average by 48%, with shorter surgical depth; however, surgical freedom was inferior to that of the binostril approach. Copyright © 2017 Elsevier Inc. All rights reserved.

  8. Comprehensive review on endonasal endoscopic sinus surgery

    Science.gov (United States)

    Weber, Rainer K.; Hosemann, Werner

    2015-01-01

    Endonasal endoscopic sinus surgery is the standard procedure for surgery of most paranasal sinus diseases. Appropriate frame conditions provided, the respective procedures are safe and successful. These prerequisites encompass appropriate technical equipment, anatomical oriented surgical technique, proper patient selection, and individually adapted extent of surgery. The range of endonasal sinus operations has dramatically increased during the last 20 years and reaches from partial uncinectomy to pansinus surgery with extended surgery of the frontal (Draf type III), maxillary (grade 3–4, medial maxillectomy, prelacrimal approach) and sphenoid sinus. In addition there are operations outside and beyond the paranasal sinuses. The development of surgical technique is still constantly evolving. This article gives a comprehensive review on the most recent state of the art in endoscopic sinus surgery according to the literature with the following aspects: principles and fundamentals, surgical techniques, indications, outcome, postoperative care, nasal packing and stents, technical equipment. PMID:26770282

  9. Oronasal complications in patients after transsphenoidal hypophyseal surgery Complicações oronasais em pacientes pós-abordagem hipofisária via transesfenoidal

    Directory of Open Access Journals (Sweden)

    Carolina Petry

    2009-06-01

    Full Text Available Transsphenoidal surgery is the most commonly used surgical procedure to handle the hypophyseal region, sometimes associated with oronasal complications. MATERIAL AND METHODS/AIM: To evaluate prospectively (specific questionnaire, clinical evaluation undiagnosed chronic oronasal complications in patients submitted to conventional transsphenoidal adenomectomy surgery, operated at different neurosurgery services more than 6 months ago. RESULTS: 49 patients were evaluated, 37/45 presented macroadenoma. 28,5% were submitted to more than one intervention, 2/5 transsphenoidally. Transsphenoidal approach 92.8% through sublabial route. No patient had spontaneous complaint. With the specific questionnaire 63.2% presented complaints. One patient presented an oronasal fistula, 1 stenosis of the nasal valve area with external nasal deformity. Rhinoscopy detected alterations in 77.5%, nasal endoscopy in 87.7%. Septal perforation was present in 10/12 patients with scabs and 2 with purulent secretion. All 4 patients submitted to 2 transsphenoidal approaches presented septal perforation and nasal synechiae. In the endonasal, synechiae (2, alteration in medium meatus (1 and stenosis of the nasal valve area (1 were observed. Only two patients presented normal evaluation. CONCLUSION: A high incidence of nasal complications after conventional transsphenoidal surgery observed through examination and not reported spontaneously point to the need of otorhinolaryngological investigation complemented by nasal endoscopy in patients submitted to procedures through this route.A cirurgia transesfenoidal é o procedimento cirúrgico mais utilizado para abordagem da região hipofisária, sendo por vezes associada a complicações oronasais. MATERIAL E MÉTODOS/OBJETIVO: Estudo prospectivo, através de questionário específico e avaliação clínica complicações oronasais crônicas não-diagnosticadas, em pacientes submetidos à cirurgia transesfenoidal convencional em

  10. Transcranial Evacuation of Atypical Progressive Supradiaphragmatic Hematoma After Transsphenoidal Complete Resection of Pituitary Adenoma.

    Science.gov (United States)

    Metwali, Hussam; Fahlbusch, Rudolf

    2017-06-01

    Supradiaphragmatic hematoma is a type of hematoma that occurs after transsphenoidal (TS) resection of pituitary adenoma and requires special management. Two patients had symptomatic supradiaphragmatic hematomas after total TS resection of pituitary adenomas in the absence of vascular anomalies. Both patients also had hydrocephalus at the time of diagnosis of the hematoma. The initial endoscopic endonasal inspection showed no subdiaphragmatic bleeding. The hematoma was evacuated via a frontolateral approach after insertion of an external ventricular drain (EVD). The supradiaphragmatic hematoma could be clinically and radiologically distinguished. It presented early with visual deterioration without headache. The patients developed hydrocephalus, which was associated with deterioration of level of consciousness. Radiologically, the hematoma filled the suprasellar space and was associated with the extension of bleeding in the basal cisterns. Recovery was good in both patients. There were no permanent neurologic deficits. The EVD was removed in both patients. One patient required a ventriculoperitoneal shunt because of delayed hydrocephalus. Supradiaphragmatic hematoma can be clinically and radiologically distinguished from other types of hematoma occurring after TS resection of pituitary adenoma. Transcranial surgery should be performed to manage supradiaphragmatic hematoma, when symptomatic. Insertion of an EVD at the time of evacuation is mandatory to relax the brain and to alleviate the hydrocephalus. Copyright © 2017 Elsevier Inc. All rights reserved.

  11. Trans-sphenoidal excision of craniopharyngiomas.

    Directory of Open Access Journals (Sweden)

    Nagpal R

    1991-04-01

    Full Text Available Craniopharyngiomas have been by and large excised by the transcranial route. Since 1982, 11 patients have been operated by the traus-sphensidal route in the department. The clinical features with which they were presented, diagnostic investigations, details of surgical procedures and follow-up analysis is being presented here. A retrospective study of radiological investigation was done to determine the features that help decide the choice of surgical approach to these lesions. Only lesions that were primarily intrasellar, cystic and those that expanded the sella could be treated by the trans-sphenoidal route. Associated suprasellar extensions could also be removed. Predominantly calcified or firm, fleshy tumours lent themselves poorly to removal by the trans-sphenoidal route.

  12. Comparison of endoscopic endonasal and bifrontal craniotomy approaches for olfactory groove meningiomas: A matched pair analysis of outcomes and frontal lobe changes on MRI.

    Science.gov (United States)

    de Almeida, John R; Carvalho, Felipe; Vaz Guimaraes Filho, Francisco; Kiehl, Tim-Rasmus; Koutourousiou, Maria; Su, Shirley; Vescan, Allan D; Witterick, Ian J; Zadeh, Gelareh; Wang, Eric W; Fernandez-Miranda, Juan C; Gardner, Paul A; Gentili, Fred; Snyderman, Carl H

    2015-11-01

    We compare the outcomes and postoperative MRI changes of endoscopic endonasal (EEA) and bifrontal craniotomy (BFC) approaches for olfactory groove meningiomas (OGM). All patients who underwent either BFC or EEA for OGM were eligible. Matched pairs were created by matching tumor volumes of an EEA patient with a BFC patient, and matching the timing of the postoperative scans. The tumor dimensions, peritumoral edema, resectability issues, and frontal lobe changes were recorded based on preoperative and postoperative MRI. Postoperative fluid-attenuated inversion recovery (FLAIR) hyperintensity and residual cystic cavity (porencephalic cave) volume were compared using univariable and multivariable analyses. From a total of 70 patients (46 EEA, 24 BFC), 10 matched pairs (20 patients) were created. Three patients (30%) in the EEA group and two (20%) in the BFC had postoperative cerebrospinal fluid leaks (p=0.61). Gross total resections were achieved in seven (70%) of the EEA group and nine (90%) of the BFC group (p=0.26), and one patient from each group developed a recurrence. On postoperative MRI, there was no significant difference in FLAIR signal volumes between EEA and BFC approaches (6.9 versus 13.3 cm(3); p=0.17) or in porencephalic cave volumes (1.7 versus 5.0 cm(3); p=0.11) in univariable analysis. However, in a multivariable analysis, EEA was associated with less postoperative FLAIR change (p=0.02) after adjusting for the volume of preoperative edema. This study provides preliminary evidence that EEA is associated with quantifiable improvements in postoperative frontal lobe imaging. Copyright © 2015 Elsevier Ltd. All rights reserved.

  13. Endoscopic trans-sphenoidal drainage of petrous apex cholesterol ...

    African Journals Online (AJOL)

    Cholesterol granulomas of the petrous apex are rare lesions that pose challenging surgical decisions and approaches when attempting surgical drainage. In this article we present 2 cases of successful surgical management using an endoscopic trans-sphenoidal approach and review the requirements and considerations ...

  14. Characteristics of meningitis following transsphenoidal endoscopic surgery: a case series and a systematic literature review.

    Science.gov (United States)

    Pagliano, Pasquale; Caggiano, Chiara; Ascione, Tiziana; Solari, Domenico; Di Flumeri, Giusy; Cavallo, Luigi Maria; Tortora, Fabio; Cappabianca, Paolo

    2017-12-01

    Meningitis occurs in 0.8-1.5% of patients undergoing neurosurgery. The aim of the study was to evaluate the characteristics of meningitis after endoscopic endonasal transsphenoidal surgery (EETS) comparing the findings retrieved to those highlighted by literature search. Patients treated by EETS during an 18-year period in the Department of Neurosurgery of 'Federico II' University of Naples were evaluated and included in the study if they fulfilled criteria for meningitis. Epidemiological, demographic, laboratory, and microbiological findings were evaluated. A literature research according to PRISMA methodology completed the study. EETS was performed on 1450 patients, 8 of them (0.6%) had meningitis [median age 46 years (range 33-73)]. Endoscopic surgery was performed 1-15 days (median 4 days) before diagnosis. Meningeal signs were always present. CSF examination revealed elevated cells [median 501 cells/μL (range 30-5728)], high protein [median 445 mg/dL (range 230-1210)], and low glucose [median 10 mg/dL (range 1-39)]. CSF culture revealed Gram-negative bacteria in four cases (Klebsiella pneumoniae, Escherichia coli, Alcaligenes spp., and Haemophilus influenzae), Streptococcus pneumoniae in two cases, Aspergillus fumigatus in one case. An abscess occupying the surgical site was observed in two cases. Six cases reported a favorable outcome; two died. Incidence of meningitis approached to 2%, as assessed by the literature search. Incidence of meningitis after EETS is low despite endoscope goes through non-sterile structures; microorganisms retrieved are those present within sinus microenvironment. Meningitis must be suspected in patients with persistent fever and impaired conscience status after EETS.

  15. A physical simulator for endoscopic endonasal drilling techniques: technical note.

    Science.gov (United States)

    Tai, Bruce L; Wang, Anthony C; Joseph, Jacob R; Wang, Page I; Sullivan, Stephen E; McKean, Erin L; Shih, Albert J; Rooney, Deborah M

    2016-03-01

    In this paper, the authors present a physical model developed to teach surgeons the requisite drilling techniques when using an endoscopic endonasal approach (EEA) to the skull base. EEA is increasingly used for treating pathologies of the ventral and ventrolateral cranial base. Endonasal drilling is a unique skill in terms of the instruments used, the long reach required, and the restricted angulation, and gaining competency requires much practice. Based on the successful experience in creating custom simulators, the authors used 3D printing to build an EEA training model from post-processed thin-cut head CT scans, formulating the materials to provide realistic haptic feedback and endoscope handling. They performed a preliminary assessment at 2 institutions to evaluate content validity of the simulator as the first step of the validation process. Overall results were positive, particularly in terms of bony landmarks and haptic response, though minor refinements were suggested prior to use as a training device.

  16. Mechanism and surgical management of transsellar transsphenoidal encephalocele.

    Science.gov (United States)

    Yang, Zhijun; Wang, Zhenmin; Wang, Bo; Liu, Pinan

    2015-12-01

    We performed a retrospective study to assess the mechanisms and surgical strategies for transsellar transsphenoid encephalocele, a rare type of basal encephalocele. Its clinical presentations include multiple endocrine disturbances, visual deficits, cerebrospinal fluid rhinorrhea and dyspnea. However, little is known about the occurrence and optimal treatment of this disease. We retrospectively reviewed six patients who were treated in our hospital from October 2003 to September 2013; five male patients and one female, with an average age of 10 years (range: 2 - 28). We collected data on their general condition, medical history, clinical features, and outcomes. An endoscopic transsphenoidal approach was used for five patients, and one refused surgery. All patients had similar imaging findings, and their pituitary gland could not be seen on MRI. Five of the patients showed gradual disease progression. The clinical symptoms were endocrine disturbance (n=6), decreased visual acuity (n=5), dyspnea (n=3) and cerebrospinal fluid rhinorrhea (n=2). Three of the patients also had a cleft palate. Two patients suffered serious symptoms of fever, tachyarrhythmia, and electrolyte disturbance postoperatively. After a long follow-up period, the symptoms remained stable or improved in all patients postoperatively, but worsened in the patient who did not have a surgical intervention. No mortalities were recorded. This disease may result from pituitary dysplasia, and the symptoms develop as the patients grow. Surgical interventions can be helpful for symptom management, the optimal treatment being a transsphenoidal approach. Those patients with milder symptoms preoperatively have a better prognosis. Copyright © 2015 Elsevier Ltd. All rights reserved.

  17. Extended endoscopic endonasal skull base surgery: from the sella to the anterior and posterior cranial fossa

    NARCIS (Netherlands)

    Oostra, Amanda; van Furth, Wouter; Georgalas, Christos

    2012-01-01

    Skull base surgery has gone through significant changes with the development of extended endoscopic endonasal approaches over the last decade. Initially used for the transphenoidal removal of hypophyseal adenomas, the endoscopic transnasal approach gradually evolved into a way of accessing the whole

  18. Endoscopic endonasal resection of cavernous hemangioma of the palate

    Directory of Open Access Journals (Sweden)

    Kristina Piastro

    2017-11-01

    Full Text Available Hemangiomas are a common presentation in the head and neck, but intraosseous hemangiomas are exceedingly rare and account for only 1% of bone tumors. The hard palate is a unique anatomic structure consisting of mucosa rich in minor salivary glands, and is firmly attached to the palatine process of the maxilla and the horizontal plate of the palatine bone. Neoplasms of the hard palate are extremely rare and may display unique characteristics and histologic findings. Whether benign or malignant, the therapy of choice for such tumors is surgical excision performed through a transoral approach, which carries a significant risk of oronasal and oroantral fistula formation. This paper describes the use of an endoscopic endonasal technique for resection of a rare case of a cavernous hemangioma of the hard palate. Resection of favorable benign lesions like palatal hemangiomas are more likely to be successful via this endoscopic endonasal technique which avoids the traditional transoral palatal approach and thus reduces the risk of oronasal and oroantral fistulae. No complications in the immediate postoperative nor within a 1-year follow-up period were observed.

  19. Quality of life following endonasal skull base surgery.

    Science.gov (United States)

    Pant, Harshita; Bhatki, Amol M; Snyderman, Carl H; Vescan, Allan D; Carrau, Ricardo L; Gardner, Paul; Prevedello, Daniel; Kassam, Amin B

    2010-01-01

    The importance of quality of life (QOL) outcomes following treatments for head and neck tumors are now increasingly appreciated and measured to improve medical and surgical care for these patients. An understanding of the definitions in the setting of health care and the use of appropriate QOL instruments and measures are critical to obtain meaningful information that guides decision making in various aspects of patient health care. QOL outcomes following cranial base surgery is only recently being defined. In this article, we describe the current published data on QOL outcomes following cranial base surgery and provide preliminary prospective data on QOL outcomes and sinonasal morbidity in patients who underwent endonasal cranial base surgery for management of various skull base tumors at our institution. We used a disease-specific multidimensional instrument to measure QOL outcomes in these patients. Our results show that although sinonasal morbidity is increased, this is temporary, and the vast majority of patients have a very good QOL by 4 to 6 months after endonasal approach to the cranial base.

  20. Ethmoidal encephalocele associated with cerebrospinal fluid fistula: indications and results of mini-invasive transnasal approach.

    Science.gov (United States)

    Fraioli, Mario Francesco; Umana, Giuseppe Emanuele; Fiorucci, Giulia; Fraioli, Chiara

    2014-03-01

    Anterior skull base defects with encephalocele in adults are quite rare and can be a cause of spontaneous rhinoliquorrhea; however, cerebrospinal fluid (CSF) fistula can be not rarely misdiagnosed for several months or years. Five adult patients affected by ethmoidal encephalocele with CSF fistula were treated in our institute from 2006 through to 2011. Onset of clinical history was represented by rhinoliquorrhea, which was precociously recognized in only 1 patient; in the other 4, it was misdiagnosed for a period ranging from 11 months to 5 years. After clinical diagnosis of CSF fistula and after brain magnetic resonance imaging, ethmoidal encephalocele was evident in all patients; preoperative study was completed by spiral computed tomography scan, to clearly identify the skull base bone defect. All patients were operated on by transsphenoidal endonasal endoscope-assisted microsurgical approach through 1 nostril. The herniated brain was coagulated and removed, and reconstruction of cranial base was performed. Postoperative rhinoliquorrhea or other complications did not occur in any patient at short and late follow-up. All patients were discharged after a few days. Endonasal endoscope-assisted microsurgical approach was effective in exposing and repairing the ethmoidal bone defect; tridimensional vision and wide lateral and superior exposition of the operative field were possible in each patient, thanks to the use of microscope and angulated endoscope.

  1. Transsellar transsphenoidal encephalocele: A series of four cases

    OpenAIRE

    Yashpal S Rathore; Sumit Sinha; A K Mahapatra

    2011-01-01

    Transsellar transsphenoidal encephalocele is the least common type of basal encephalocele. We present a series of four cases of transsellar transsphenoidal encephalocele. Clinical findings, imaging reviews, surgical repair techniques and postoperative morbidity are discussed with the relevant literature. Non contrast CT scan head with 3D reconstruction and magnetic resonance imaging should be done in all patients of transsphenoidal encephalocele. Endocrine assessment is also essential. Repair...

  2. Predictors of sinonasal quality of life and nasal morbidity after fully endoscopic transsphenoidal surgery.

    Science.gov (United States)

    Little, Andrew S; Kelly, Daniel; Milligan, John; Griffiths, Chester; Prevedello, Daniel M; Carrau, Ricardo L; Rosseau, Gail; Barkhoudarian, Garni; Otto, Bradley A; Jahnke, Heidi; Chaloner, Charlene; Jelinek, Kathryn L; Chapple, Kristina; White, William L

    2015-06-01

    Despite the increasing application of endoscopic transsphenoidal surgery for pituitary lesions, the prognostic factors that are associated with sinonasal quality of life (QOL) and nasal morbidity are not well understood. The authors examine the predictors of sinonasal QOL and nasal morbidity in patients undergoing fully endoscopic transsphenoidal surgery. An exploratory post hoc analysis was conducted of patients who underwent endoscopic pituitary surgery and were enrolled in a prospective multicenter QOL study. End points of the study included patient-reported sinonasal QOL and objective nasal endoscopy findings. Multivariate models were developed to determine the patient and surgical factors that correlated with QOL at 2 weeks through 6 months after surgery. This study is a retrospective review of a subgroup of patients studied in the clinical trial "Rhinological Outcomes in Endonasal Pituitary Surgery" (clinical trial no. NCT01504399, clinicaltrials.gov ). Data from 100 patients who underwent fully endoscopic transsphenoidal surgery were included. Predictors of a lower postoperative sinonasal QOL at 2 weeks were use of nasal splints (p = 0.039) and female sex at the trend level (p = 0.061); at 3 months, predictors of lower QOL were the presence of sinusitis (p = 0.025), advancing age (p = 0.044), and use of absorbable nasal packing (p = 0.014). Health status (multidimensional QOL) was also predictive at 2 weeks (p = 0.001) and 3 months (p < 0.001) and was the only significant predictor of sinonasal QOL at 6 months (p < 0.001). A Kaplan-Meier analysis was performed to study time to resolution of nasal crusting, mucopurulence, and synechia as observed during nasal endoscopy after surgery. The mean time (± SEM) to absence of nasal crusting was 16.3 ± 2.1 weeks, mucopurulence was 6.2 ± 1.1 weeks, and synechia was 4.4 ± 0.5 weeks. Use of absorbable nasal packing was associated with more severe mucopurulence. Sinonasal QOL following endoscopic pituitary surgery

  3. Laser-assisted surgery of endonasal diseases

    Science.gov (United States)

    Sroka, Ronald; Leunig, Andreas; Janda, P.; Rosler, P.; Grevers, G.; Baumgartner, Reinhold

    2000-06-01

    Clinical studies were performed to assess the clinical outcome of laser assisted endonasal turbinate surgery in long-term. By means of a pulsed Ho:YAG laser emitting at (lambda) equals 2100nm 57 patients suffering form nasal obstruction due to allergic rhinitis and vasomotoric rhinitis were treated under local anesthesia. Furthermore 50 patients were treated by means of light of a diode laser. The light was fed into a fiber being introduced into a fiber guidance system which serves for suction of smoke and pyrolyse products. The distal part of this system could be bent in the range of -5 degrees up to 45 degrees due to the optical axes of the fiber. The study was conducted by a standardized questionnaire, photo documentation, allergy test, mucocilliar function test, rhinomanometry, radiology and histology. Within 2 weeks after laser treatment a significant improvement of nasal airflow correlating to the extent of the ablated turbinate tissue could be determined. This effect lasted up until 1 year post treatment resulting in an improved quality of life in more than 80 percent of the patients. Side effects like nasal dryness and pain were rare, no immediate complications were observed. The total treatment time took 3-8 minutes/turbinate and nasal packing was not necessary after the laser procedure. In conclusion laser treatment by means of the fiber guidance system can be performed as an outpatient procedure under local anesthesia with excellent ablation of soft tissue in a short treatment time with promising results. It will become a time and cost effective treatment modality in endonasal laser surgery.

  4. Non-endoscopic Mechanical Endonasal Dacryocystorhinostomy

    Directory of Open Access Journals (Sweden)

    Mohammad Etezad Razavi

    2011-01-01

    Full Text Available To circumvent the disadvantages of endoscopic dacryocystorhinostomy such as small rhinostomy size, high failure rate and expensive equipment, we hereby introduce a modified technique of non-endoscopic mechanical endonasal dacryocystorhinostomy (NE-MEDCR. Surgery is performed under general anesthesia with local decongestion of the nasal mucosa. A 20-gauge vitrectomy light probe is introduced through the upper canaliculus until it touches the bony medial wall of the lacrimal sac. While directly viewing the transilluminated target area, a nasal speculum with a fiber optic light carrier is inserted. An incision is made vertically or in a curvilinear fashion on the nasal mucosa in the lacrimal sac down to the bone using a Freer periosteum elevator. Approximately 1 to 1.5 cm of nasal mucosa is removed with Blakesley forceps. Using a lacrimal punch, the thick bone of the frontal process of the maxilla is removed and the inferior half of the sac is uncovered. The lacrimal sac is tented into the surgical site with the light probe and its medial wall is incised using a 3.2 mm keratome and then excised using the Blakesley forceps. The procedure is completed by silicone intubation. The NE-MEDCR technique does not require expensive instrumentation and is feasible in any standard ophthalmic surgical setting.

  5. Extended endoscopic endonasal surgery using three-dimensional endoscopy in the intra-operative MRI suite for supra-diaphragmatic ectopic pituitary adenoma.

    Science.gov (United States)

    Fuminari, Komatsu; Hideki, Atsumi; Manabu, Osakabe; Mitsunori, Matsumae

    2015-01-01

    We describe a supra-diaphragmatic ectopic pituitary adenoma that was safely removed using the extended endoscopic endonasal approach, and discuss the value of three-dimensional (3D) endoscopy and intra-operative magnetic resonance imaging (MRI) to this type of procedure. A 61-year-old-man with bitemporal hemianopsia was referred to our hospital, where MRI revealed an enhanced suprasellar tumor compressing the optic chiasma. The tumor extended on the planum sphenoidale and partially encased the right internal carotid artery. An endocrinological assessment indicated normal pituitary function. The extended endoscopic endonasal approach was taken using a 3D endoscope in the intraoperative MRI suite. The tumor was located above the diaphragma sellae and separated from the normal pituitary gland. The pathological findings indicated non-functioning pituitary adenoma and thus the tumor was diagnosed as a supra-diaphragmatic ectopic pituitary adenoma. Intra-operative MRI provided useful information to minimize dural opening and the supra-diaphragmatic ectopic pituitary adenoma was removed from the complex neurovascular structure via the extended endoscopic endonasal approach under 3D endoscopic guidance in the intra-operative suite. Safe and effective removal of a supra-diaphragmatic ectopic pituitary adenoma was accomplished via the extended endoscopic endonasal approach with visual information provided by 3D endoscopy and intra-operative MRI.

  6. Nasopharyngeal Mass Diagnosed as Transsphenoidal Encephalocele in an Adult Patient.

    Science.gov (United States)

    Ertas, Burak; Aksoy, Elif Ayanoglu; Unal, Omer Faruk

    2015-11-01

    Transsphenoidal encephalocele, a rare congenital malformation, is generally diagnosed during childhood when investigating the reason for complaints such as nasal obstruction and recurring cerebrospinal fluid fistula. In this adult patient, the authors identified an asymptomatic transsphenoidal encephalocele after requested monitoring of a pedunculated mass detected in the nasopharynx during nasal endoscopy. After evaluation, the authors decided to follow the patient. Few cases of transsphenoidal encephalocele have been reported, and even fewer have been reported in older patients, with no other anomaly or symptoms. The success of surgical treatment for these masses is debatable. The authors did not consider surgery for this asymptomatic case. With this case presentation, the authors wish to emphasize that without making radiologic assessments of any masses identified in a nasopharyngeal examination, it would be inappropriate to perform a biopsy or any intervention.

  7. A rare cause of short stature: transsphenoidal encephalocele.

    Science.gov (United States)

    Bayram, Özhan; Sebahat, Ağladıoğlu Yılmaz; Kadir, Ağladıoğlu; Ali, Koçyiğit

    2014-12-01

    Basal encephaloceles are rare, accounting for about 1.5% of all encephaloceles. Transsphenoidal encephaloceles represent less than 5% of basal encephaloceles. Respiratory and feeding difficulties due to mass effect in the oral or nasal cavity and episodes of recurrent meningitis are the main clinical features. Diagnosis is established in the first year of life, but without characteristic facies, the diagnosis can be delayed to adolescence or adulthood. We report the case of a 10-year-old boy who presented with short stature and eventually was diagnosed with a growth hormone deficiency because of mass effect of transsphenoidal encephalocele. Unusual presentation of an encephalocele as a short stature is described.

  8. Clinical comparison of remifentanil-sevoflurane vs. remifentanil-propofol for endoscopic endonasal transphenoidal surgery.

    Science.gov (United States)

    Cafiero, T; Cavallo, L M; Frangiosa, A; Burrelli, R; Gargiulo, G; Cappabianca, P; de Divitiis, E

    2007-05-01

    Endoscopic endonasal transphenoidal surgery has been recently proposed as a minimally invasive procedure for the treatment of pituitary adenomas. The main objective of the anaesthesiologist is to induce sufficient haemodynamic control together with rapid recovery at the end of surgery. The aim of this study was to examine recovery profile, surgical operative conditions and haemodynamic differences using remifentanil infusion with either propofol target controlled infusion system or sevoflurane. Forty-four adult patients were enrolled in a prospective, randomized, single-blind, two-group study: Group P received propofol target controlled infusion system and remifentanil; Group S received sevoflurane and remifentanil for maintenance of anaesthesia. No statistically significant differences between the two groups with regards to the haemodynamic changes, operative conditions as assessed by a four-step bleeding score (0-3), were obtained. Recovery times were considerably shorter after remifentanil-sevoflurane in comparison with remifentanil-propofol target controlled infusion system group (7.4 vs. 12.8 min, P < 0.01). This study demonstrates that sevoflurane-remifentanil gives a faster recovery and equivalent intraoperative status compared with propofol target controlled infusion system with remifentanil for the endoscopic endonasal transphenoidal approach.

  9. Outcome of Transsphenoidal Surgery for Cushing Disease: A Single-Center Experience Over 32 Years.

    Science.gov (United States)

    Chandler, William F; Barkan, Ariel L; Hollon, Todd; Sakharova, Alla; Sack, Jayson; Brahma, Barunashish; Schteingart, David E

    2016-02-01

    Transsphenoidal surgery is the standard approach for treating Cushing disease. Evidence is needed to document effectiveness. To analyze results of transsphenoidal surgery in 276 consecutive patients, including 19 children. Medical records were reviewed for patients treated initially with surgery for Cushing disease from 1980 to 2012. Radiographic features, pathology, remissions, recurrences, and complications were recorded. Patients were categorized for statistical analysis based on tumor size (microadenomas, macroadenomas, and negative imaging) and remission type (type 1 = morning cortisol ≤3 μg/dL; type 2 = morning cortisol normal). Females comprised 78% of patients and were older than men. Imaging showed 50% microadenomas, 13% macroadenomas, and 37% negative for tumor. Remission rates for microadenomas, macroadenomas, and negative imaging were 89%, 66%, and 71%, respectively. Patients with microadenomas were more likely to have type 1 remission. Pathology showed adrenocorticotropic hormone-secreting adenomas in 82% of microadenomas, in 100% of macroadenomas, and in 43% of negative imaging. The incidence of hyperplasia was 8%. The finding of hyperplasia or no tumor on pathology predicted treatment failure. The recurrence rate was 17%, with an average time to recurrence of 4.0 years. Patients with type 1 remission had a lower rate of recurrence (13% type 1 vs 50% type 2) and a longer time to recurrence. Children had similar imaging findings, remission rates, and pathology. There were no operative deaths. Transsphenoidal surgery provides a safe and effective treatment for Cushing disease. For both adults and children, the best outcomes occurred in patients with microadenomas and/or those with type 1 remission.

  10. Long-term follow-up on Cushing disease patient after transsphenoidal surgery

    Directory of Open Access Journals (Sweden)

    Insook Jeong

    2014-09-01

    Full Text Available Cushing disease is caused by excessive adrenocorticotropic hormone (ACTH production by the pituitary adenoma. Transsphenoidal surgery is its first-line treatment. The incidence of Cushing disease in children and adolescents is so rare that long-term prognoses have yet to be made in most cases. We followed-up on a 16-year-old male Cushing disease patient who presented with rapid weight gain and growth retardation. The laboratory findings showed increased 24-hour urine free cortisol and lack of overnight cortisol suppression by low-dose dexamethasone test. The serum cortisol and 24-hour urine free cortisol, by high-dose dexamethasone test, also showed a lack of suppression, and a bilateral inferior petrosal sinus sampling suggested lateralization of ACTH secretion from the right-side pituitary gland. However, after a right hemihypophysectomy by the transsphenoidal approach, the 24-hour urine free cortisol levels were persistently high. Thus the patient underwent a total hypophysectomy, since which time he has been treated with hydrocortisone, levothyroxine, recombinant human growth hormone, and testosterone enanthate. Intravenous bisphosphonate for osteoporosis had been administered for three years. At his current age of 26 years, his final height had attained the target level range; his bone mineral density was normal, and his pubic hair was Tanner stage 4. This report describes the long-term treatment course of a Cushing disease patient according to growth profile, pubertal status, and responses to hormone replacement therapy. The clinical results serve to emphasize the importance of growth optimization, puberty, and bone health in the treatment management of Cushing disease patients who have undergone transsphenoidal surgery.

  11. Long-term follow-up on Cushing disease patient after transsphenoidal surgery.

    Science.gov (United States)

    Jeong, Insook; Oh, Moonyeon; Kim, Ja Hye; Cho, Ja Hyang; Choi, Jin-Ho; Yoo, Han-Wook

    2014-09-01

    Cushing disease is caused by excessive adrenocorticotropic hormone (ACTH) production by the pituitary adenoma. Transsphenoidal surgery is its first-line treatment. The incidence of Cushing disease in children and adolescents is so rare that long-term prognoses have yet to be made in most cases. We followed-up on a 16-year-old male Cushing disease patient who presented with rapid weight gain and growth retardation. The laboratory findings showed increased 24-hour urine free cortisol and lack of overnight cortisol suppression by low-dose dexamethasone test. The serum cortisol and 24-hour urine free cortisol, by high-dose dexamethasone test, also showed a lack of suppression, and a bilateral inferior petrosal sinus sampling suggested lateralization of ACTH secretion from the right-side pituitary gland. However, after a right hemihypophysectomy by the transsphenoidal approach, the 24-hour urine free cortisol levels were persistently high. Thus the patient underwent a total hypophysectomy, since which time he has been treated with hydrocortisone, levothyroxine, recombinant human growth hormone, and testosterone enanthate. Intravenous bisphosphonate for osteoporosis had been administered for three years. At his current age of 26 years, his final height had attained the target level range; his bone mineral density was normal, and his pubic hair was Tanner stage 4. This report describes the long-term treatment course of a Cushing disease patient according to growth profile, pubertal status, and responses to hormone replacement therapy. The clinical results serve to emphasize the importance of growth optimization, puberty, and bone health in the treatment management of Cushing disease patients who have undergone transsphenoidal surgery.

  12. Predictors of resource utilization in transsphenoidal surgery for Cushing disease.

    Science.gov (United States)

    Little, Andrew S; Chapple, Kristina

    2013-08-01

    The short-term cost associated with subspecialized surgical care is an increasingly important metric and economic concern. This study sought to determine factors associated with hospital charges in patients undergoing transsphenoidal surgery for Cushing disease in an effort to identify the drivers of resource utilization. The authors analyzed the Nationwide Inpatient Sample (NIS) hospital discharge database from 2007 to 2009 to determine factors that influenced hospital charges in patients who had undergone transsphenoidal surgery for Cushing disease. The NIS discharge database approximates a 20% sample of all inpatient admissions to nonfederal US hospitals. A multistep regression model was developed that adjusted for patient demographics, acuity measures, comorbidities, hospital characteristics, and complications. In 116 hospitals, 454 transsphenoidal operations were performed. The mean hospital charge was $48,272 ± $32,060. A multivariate regression model suggested that the primary driver of resource utilization was length of stay (LOS), followed by surgeon volume, hospital characteristics, and postoperative complications. A 1% increase in LOS increased hospital charges by 0.60%. Patient charges were 13% lower when performed by high-volume surgeons compared with low-volume surgeons and 22% lower in large hospitals compared with small hospitals. Hospital charges were 12% lower in cases with no postoperative neurological complications. The proposed model accounted for 46% of hospital charge variance. This analysis of hospital charges in transsphenoidal surgery for Cushing disease suggested that LOS, hospital characteristics, surgeon volume, and postoperative complications are important predictors of resource utilization. These findings may suggest opportunities for improvement.

  13. Endoscopic trans-sphenoidal drainage of petrous apex cholesterol ...

    African Journals Online (AJOL)

    Georgalas C, Kania R, Guichard JP, Sauvaget E, Tran Ba Huy P, Herman. P. Endoscopic transsphenoidal surgery for cholesterol granulomas involving the petrous apex. Clin Otolaryngol 2008; 33: 38-42. 3. Graham MD, Kemink JL, Latack JT, Kartush JM. The giant cholesterol cyst of the petrous apex: A distinct clinical entity.

  14. Effectiveness of caudal septal extension graft application in endonasal septoplasty

    Directory of Open Access Journals (Sweden)

    Yunus Karadavut

    Full Text Available Abstract Introduction Septal deviation is a common disease seen in daily otorhinolaryngology practice and septoplasty is a commonly performed surgical procedure. Caudal septum deviation is also a challenging pathology for ear, nose, and throat specialists. Many techniques are defined for caudal septal deviation. Objective To evaluate the effectiveness of caudal septal extension graft (CSEG application in patients who underwent endonasal septoplasty for a short and deviated nasal septum. Methods Forty patients with nasal septal deviation, short nasal septum, and weak nasal tip support who underwent endonasal septoplasty with or without CSEG placement between August 2012 and June 2013 were enrolled in this study. Twenty patients underwent endonasal septoplasty with CSEG placement. The rest of the group, who rejected auricular or costal cartilage harvest for CSEG placement, underwent only endonasal septoplasty without any additional intervention. Using the Nasal Obstruction Symptom Evaluation (NOSE and Rhinoplasty Outcome Evaluation (ROE questionnaires, pre- and post-operative acoustic rhinometer measurements were evaluated to assess the effect of CESG placement on nasal obstruction. Results In the control group, preoperative and postoperative minimal cross-sectional areas (MCA1 were 0.44 ± 0.10 cm2 and 0.60 ± 0.11 cm2, respectively (p < 0.001. In the study group, pre- and postoperative MCA1 values were 0.45 ± 0.16 cm2 and 0.67 ± 0.16 cm2, respectively (p < 0.01. In the control group, the nasal cavity volume (VOL1 value was 1.71 ± 0.21 mL preoperatively and 1.94 ± 0.17 mL postoperatively (p < 0.001. In the study group, pre- and postoperative VOL1s were 1.72 ± 0.15 mL and 1.97 ± 0.12 mL, respectively (p < 0.001. Statistical analysis of postoperative MCA1 and VOL1 values in the study and the control groups could not detect any significant intergroup difference (p = 0.093 and 0.432, respectively. In the study group, mean nasolabial angles were

  15. Endoscopic endonasal transphenoidal surgery using the BrainLAB® Headband for navigation without rigid fixation.

    Science.gov (United States)

    Duque, Sara G; Gorrepati, Ramana; Kesavabhotla, Kartik; Huang, Clark; Boockvar, John A

    2014-07-01

    The number of lesions of the skull base currently resected via endoscopic, endonasal, transphenoidal approach has increased. We have successfully treated 63 consecutive patients with pituitary lesions using this technique in combination with BrainLAB reference headband and laser surface scanning (BrainLAB(®), Heimstetten, Germany) for surgical navigation. This technique affords several advantages over neuronavigation based on adhesive-mounted fiducial registration. Rigid fixation in a Mayfield clamp is not required, which allows for flexibility with respect to positioning of the head during the procedure. This is particularly important, as extension and flexion of the head provide greater exposure to the clivus and anterior skull base, respectively. Also, we demonstrate that this technique is safe, easy-to-use, and faster compared with other ones. Georg Thieme Verlag KG Stuttgart · New York.

  16. Immediate postoperative complications in transsphenoidal pituitary surgery: A prospective study

    Directory of Open Access Journals (Sweden)

    Tumul Chowdhury

    2014-01-01

    Full Text Available Background: Considering the important role of pituitary gland in regulating various endocrine axes and its unique anatomical location, various postoperative complications can be anticipated resulting from surgery on pituitary tumors. We examined and categorized the immediate postoperative complications according to various tumor pathologies. Materials and Methods: We carried out a prospective study in 152 consecutive patients and noted various postoperative complications during neurosurgical intensive care unit stay (within 48 hrs of hospital stay in patients undergoing transsphenoidal removal of pituitary tumors. Results: In our series, various groups showed different postoperative complications out of which, cerebrospinal fluid leak was the commonest followed by diabetes insipidus, postoperative nausea and vomiting, and hematoma at operation site. Conclusion: Various immediate postoperative complications can be anticipated in transsphenoidal pituitary surgery even though, it is considered to be relatively safe.

  17. Complicações rinossinusais após descompressão orbital em técnica externa e endonasal combinada Sinus complications after orbital decompression by combined external and endonasal technique

    Directory of Open Access Journals (Sweden)

    Rogério Pezato

    2004-06-01

    underwent orbital decompression, in the Ophthalmology Department at the Escola Paulista de Medicina-UNIFESP an orbital decompression was obtained by combined technique using endonasal access with an endoscope. RESULTS: Four patients during postoperative CT scan presented assymtomatic opacification of the maxillary or frontal sinuses. CONCLUSION: A combination of endoscopy in orbital decompression by external approach showed the effectiveness in prevention of sinusitis clinically manifested and its complications, although a longer time of follow-up is needed to understand better radiological findings 22% presented opacification of the sinuses and their consequences.

  18. Two-Dimensional High Definition Versus Three-Dimensional Endoscopy in Endonasal Skull Base Surgery: A Comparative Preclinical Study.

    Science.gov (United States)

    Rampinelli, Vittorio; Doglietto, Francesco; Mattavelli, Davide; Qiu, Jimmy; Raffetti, Elena; Schreiber, Alberto; Villaret, Andrea Bolzoni; Kucharczyk, Walter; Donato, Francesco; Fontanella, Marco Maria; Nicolai, Piero

    2017-09-01

    Three-dimensional (3D) endoscopy has been recently introduced in endonasal skull base surgery. Only a relatively limited number of studies have compared it to 2-dimensional, high definition technology. The objective was to compare, in a preclinical setting for endonasal endoscopic surgery, the surgical maneuverability of 2-dimensional, high definition and 3D endoscopy. A group of 68 volunteers, novice and experienced surgeons, were asked to perform 2 tasks, namely simulating grasping and dissection surgical maneuvers, in a model of the nasal cavities. Time to complete the tasks was recorded. A questionnaire to investigate subjective feelings during tasks was filled by each participant. In 25 subjects, the surgeons' movements were continuously tracked by a magnetic-based neuronavigator coupled with dedicated software (ApproachViewer, part of GTx-UHN) and the recorded trajectories were analyzed by comparing jitter, sum of square differences, and funnel index. Total execution time was significantly lower with 3D technology (P technology appears to confer an advantage in terms of time of execution and precision of surgical maneuvers. Copyright © 2017 Elsevier Inc. All rights reserved.

  19. Endoscopic anatomy of the approaches to the sellar area and planum sphenoidale.

    Science.gov (United States)

    Ramos, Henrique Faria; Monteiro, Tatiana Alves; Pinheiro Neto, Carlos Diógenes; Mariani, Pedro Paulo; Fortes, Felipe Sartor Guimarães; Sennes, Luiz Ubirajara

    2011-04-01

    The productive work between otolaryngologists and neurosurgeons has resulted in the emergence of endoscopic endonasal skull base surgery. The goal of the present study is to describe the endoscopic anatomy of the endonasal approach to the sellar region and planum sphenoidale, highlighting the key points of the surgical approach and the neurovascular landmarks. Descriptive study of the endoscopic endonasal dissection of 9 fresh cadavers with exposure of the anatomic structures. The endoscopic endonasal ethmoidectomy and sphenoidotomy allows an expanded access to the sellar area and planum sphenoidale. The surface anatomy of the sphenoid sinus is easily identifiable and provides safe landmarks, guiding the intracranial dissection. The endoscopic endonasal approach to the skull base by the ENT and neurosurgeon is feasible, but it requires adequate anatomical knowledge and endoscopic skills for its realization, which can be obtained by practicing in cadavers.

  20. Endoscopic anatomy of the approaches to the sellar area and planum sphenoidale

    Directory of Open Access Journals (Sweden)

    Henrique Faria Ramos

    2011-04-01

    Full Text Available The productive work between otolaryngologists and neurosurgeons has resulted in the emergence of endoscopic endonasal skull base surgery. The goal of the present study is to describe the endoscopic anatomy of the endonasal approach to the sellar region and planum sphenoidale, highlighting the key points of the surgical approach and the neurovascular landmarks. METHOD: Descriptive study of the endoscopic endonasal dissection of 9 fresh cadavers with exposure of the anatomic structures. RESULTS: The endoscopic endonasal ethmoidectomy and sphenoidotomy allows an expanded access to the sellar area and planum sphenoidale. The surface anatomy of the sphenoid sinus is easily identifiable and provides safe landmarks, guiding the intracranial dissection. CONCLUSION: The endoscopic endonasal approach to the skull base by the ENT and neurosurgeon is feasible, but it requires adequate anatomical knowledge and endoscopic skills for its realization, which can be obtained by practicing in cadavers.

  1. Cryptococcal meningitis after transnasal transsphenoidal pituitary microsurgery of ACTH-secreting pituitary adenoma

    OpenAIRE

    Liu, Yang; Feng, Ming; Yao, Yong; Deng, Kan; Bao, Xinjie; Liu, Xiaohai; Wang, Renzhi

    2017-01-01

    Abstract Rationale: Microbial infection should be regarded in the differential diagnosis of neurosurgical complications after transnasal transsphenoidal pituitary microsurgery, albeit cryptococcal meningitis is rare. This article will discuss the risk factors of cryptococcal meningitis in patients underwent transnasal transsphenoidal pituitary microsurgery, and summary the potential origins of infection. Patient concerns and diagnosis: Here, we report a case of 37-year-old male who had crypto...

  2. Comparative evaluation of atenolol and clonidine premedication on cardiovascular response to nasal speculum insertion during trans-sphenoid surgery for resection of pituitary adenoma: A prospective, randomised, double-blind, controlled study

    Directory of Open Access Journals (Sweden)

    Devendra Gupta

    2011-01-01

    Full Text Available Severe cardiovascular responses in the form of tachycardia and hypertension following nasal speculum insertion occur during sublabial rhinoseptal trans-sphenoid approach for resection of small pituitary tumours. We compare the effects of preoperative administration of clonidine (α-2 agonist and atenolol (α-blocker over haemodynamic response, caused by speculum insertion during trans-sphenoid pituitary resection. We enrolled 66 patients in age range 18-65 years, of ASA I-II, and of either sex undergoing elective sublabial rhinoseptal trans-sphenoidal hypophysectomy. Group I (control received placebo, group II (clonidine received tablet clonidine 5 μg/kg, and group III (atenolol received tablet atenolol 0.5 mg/kg. The heart rate increased on speculum insertion and 5 and 10 minutes following speculum insertion as compared to the pre-speculum values in the control group, while no change in the heart rate was observed in other groups (P<0.05. There was a rise in the mean arterial pressure during and 5, 10, and 15 minutes after nasal speculum insertion in the control group, whereas it was not seen in other groups (P<0.05. We therefore suggest that oral clonidine and oral atenolol (given 2 hours prior to surgery is an equally effective and safe method of attenuating haemodynamic response caused by nasal speculum insertion during trans-sphenoid pituitary resection.

  3. New mucosal flap modification for endonasal endoscopic dacryocystorhinostomy in Asians.

    Science.gov (United States)

    Ji, Qing-Shan; Zhong, Jing-Xiang; Tu, Yun-Hai; Wu, Wen-Can

    2012-01-01

    To describe a simple modification of fashioning the mucosal flap for endonasal endoscopic dacryocystorhinostomy (EES-DCR) in Asians and investigate its efficacy. A total of 120 patients with unilateral primary chronic dacryocystitis (PCD) were randomized into two groups: the new shaped nasal mucosal flap group (group A) and the removed nasal mucosal flap group (group B). All patients underwent standard EES-DCR. Patients in group A were performed a new shaped nasal mucosal flap covering the bared bone around the opened sac and those in group B was removed the nasal mucosal flap uncovering the bared bone. Patients were followed up for one year. The occurrence of granulation tissue, the proliferation of scar tissue and success rate of EES-DCR was compared. In the present study, complete postoperative data were acquired from 54 patients in group A and from 57 patients in group B. During process of review, the occurrence of granulation tissue was at the ostium margins account for 15% (8/54) in group A and 39% (22/57) in group B (Pbared bone around the opened sac and reduce formation of granulation tissue, lessen the risk of scar tissue formation and closure of ostium, thus improve the success rate of EES-DCR in Asians.

  4. Spontaneous reossification of the sella in transsphenoidal reoperation associated with strontium ranelate

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    Maria Mercedes Pineyro

    2017-07-01

    Full Text Available Spontaneous reossification of the sellar floor after transsphenoidal surgery has been rarely reported. Strontium ranelate, a divalent strontium salt, has been shown to increase bone formation, increasing osteoblast activity. We describe an unusual case of a young patient with Cushing’s disease who was treated with strontium ranelate for low bone mass who experienced spontaneous sellar reossification after transsphenoidal surgery. A 21-year-old male presented with Cushing’s features. His past medical history included delayed puberty diagnosed at 16 years, treated with testosterone for 3 years without further work-up. He was diagnosed with Cushing’s disease initially treated with transsphenoidal surgery, which was not curative. The patient did not come to follow-up visits for more than 1 year. He was prescribed strontium ranelate 2 g orally once daily for low bone mass by an outside endocrinologist, which he received for more than 1 year. Two years after first surgery he was reevaluated and persisted with active Cushing’s disease. Magnetic resonance image revealed a left 4 mm hypointense mass, with sphenoid sinus occupation by a hyperintense material. At repeated transsphenoidal surgery, sellar bone had a very hard consistency; surgery was complicated and the patient died. Sellar reossification negatively impacted surgery outcomes in this patient. While this entity is possible after transsphenoidal surgery, it remains unclear whether strontium ranelate could have affected sellar ossification.

  5. New mucosal flap modification for endonasal endoscopic dacryocystorhinostomy in Asians

    Directory of Open Access Journals (Sweden)

    Qing-Shan Ji

    2012-12-01

    Full Text Available AIM: To describe a simple modification of fashioning the mucosal flap for endonasal endoscopic dacryocystorhinostomy (EES-DCR in Asians and investigate its efficacy.METHODS: A total of 120 patients with unilateral primary chronic dacryocystitis (PCD were randomized into two groups: the new shaped nasal mucosal flap group (group A and the removed nasal mucosal flap group (group B. All patients underwent standard EES-DCR. Patients in group A were performed a new shaped nasal mucosal flap covering the bared bone around the opened sac and those in group B was removed the nasal mucosal flap uncovering the bared bone. Patients were followed up for one year. The occurrence of granulation tissue, the proliferation of scar tissue and success rate of EES-DCR was compared.RESULTS: In the present study, complete postoperative data were acquired from 54 patients in group A and from 57 patients in group B. During process of review, the occurrence of granulation tissue was at the ostium margins account for 15% (8/54 in group A and 39% (22/57 in group B (P<0.05. At the one-year review, scar tissue was present in 5 patients in group A compared with 18 in group B (P<0.05. The success rate of EES-DCR was 98% (53/54 in group A and 84% (48/57 in group B (P<0.05.CONCLUSION: The simple modification of fashioning nasal mucosal flap can effectively cover the bared bone around the opened sac and reduce formation of granulation tissue, lessen the risk of scar tissue formation and closure of ostium, thus improve the success rate of EES-DCR in Asians.

  6. Transsphenoidal surgery and diabetes mellitus: An analysis of inpatient data and complications.

    Science.gov (United States)

    Pines, Morgan J; Raikundalia, Milap D; Svider, Peter F; Baredes, Soly; Liu, James K; Eloy, Jean Anderson

    2015-10-01

    Transsphenoidal surgery (TSS) has emerged as the standard approach for pituitary resection due to its minimally invasive nature. There has been little analysis examining the impact of diabetes mellitus (DM) on patients undergoing TSS. In this study, we characterize DM's association with postoperative TSS complications. In addition to analysis of associated charges and patient demographics, we performed comparison of complication rates between DM and non-DM patients who have undergone TSS in recent years. The Nationwide Inpatient Sample, a database encompassing nearly 8 million inpatient hospitalizations, was evaluated for patients undergoing TSS from 2002 to 2010. Of 12,938 TSS patients, 2,173 (16.8%) had a DM diagnosis. The non-DM cohort was younger (50.1 y ± 16.6SD vs. 56.8 y ± 14.1; P diabetes insipidus (P diabetics when compared to non-DM blacks. DM is associated with greater length of stay and hospital charges among TSS patients. DM patients undergoing TSS have a significantly greater incidence of pulmonary and fluid/electrolyte complications among patients under the age of 60, and greater risk for urinary/renal complications across all ages. Despite a theoretical concern due to an impaired wound-healing in DM patients, association with cerebrospinal fluid rhinorrhea was only noted among black diabetics. 2C. © 2015 The American Laryngological, Rhinological and Otological Society, Inc.

  7. Endoscopic transsphenoidal surgery for cushing disease: techniques, outcomes, and predictors of remission.

    Science.gov (United States)

    Starke, Robert M; Reames, Davis L; Chen, Ching-Jen; Laws, Edward R; Jane, John A

    2013-02-01

    The efficacy of endoscopic transsphenoidal surgery (ETS) for Cushing disease has not been clearly established. To assess efficacy of a pure endoscopic approach for treatment of Cushing disease and determine predictors of remission. A prospectively acquired database of 61 patients undergoing ETS was reviewed. Remission was defined as postoperative morning serum cortisol of Cushing [100%], macroadenomas [87%]). At 2- to 3-month evaluations, 45 of 49 patients (91.8%) were in remission. Fifty patients were followed for at least 12 months (mean, 28 months; range, 12-72). Forty-two (84%) achieved remission from a single ETS. In these patients, there was no significant difference in remission rates between microadenomas (93%), magnetic resonance imaging-negative (70%), and macroadenomas (77%). Patients with history of previous surgery (n = 14, 23%) were 9 times less likely to achieve follow-up remission (P = .021). In-house cortisol level of Cushing disease provides high rates of remission with low rates of complications regardless of size. Although patients with a history of previous surgery are less likely to achieve remission, the majority can still achieve remission following treatment.

  8. Cryptococcal meningitis after transnasal transsphenoidal pituitary microsurgery of ACTH-secreting pituitary adenoma: A case report.

    Science.gov (United States)

    Liu, Yang; Feng, Ming; Yao, Yong; Deng, Kan; Bao, Xinjie; Liu, Xiaohai; Wang, Renzhi

    2017-07-01

    Microbial infection should be regarded in the differential diagnosis of neurosurgical complications after transnasal transsphenoidal pituitary microsurgery, albeit cryptococcal meningitis is rare. This article will discuss the risk factors of cryptococcal meningitis in patients underwent transnasal transsphenoidal pituitary microsurgery, and summary the potential origins of infection. Here, we report a case of 37-year-old male who had cryptococcal meningitis after transnasal transsphenoidal pituitary microsurgery of a relapsing ACTH-secreting pituitary adenoma. Standard therapy for Cryptococcus neoformans (fluconazole [400 mg per day] and flucytosine) was administered and followed by maintenance dose. The patient had been on treatment for one and a half years during follow-up and reported neurologically well with repeated negative cerebrospinal fluid (CSF) culture until sudden death of heart arrest. C neoformans can be a possible cause of meningitis in immunocompetent patients after transnasal transsphenoidal pituitary microsurgery. Risk factors, such as pre-existed pulmonary infection and Cushing-associated hypercortisolemia, should be stressed. Promising preventive measures may include preoperative routine sputum smear and India-ink stain for screening, preoperative treatment of cryptococcal pneumonia, postoperative antibiotic management, and a more secure skull base reconstruction. Radiation and pharmaceutical treatment may be alternative for recurrent Cushing disease.

  9. Evaluation of adenohypophyseal reserve in patients carrier of hypophyseal adenoma treated by trans-sphenoidal surgery

    International Nuclear Information System (INIS)

    Drubscky, A.T.

    1980-01-01

    Fifteen patients carrier hypophyseal adenomas, with ages varying between 16 to 53 years were studied. The patients presented sella changes to the conventional plane radiographies and were submited a surgery treatment, with acess to hypophysis by the trans-sphenoidal way. (author)

  10. Trans-sphenoidal encephalocele in association with Dandy-Walker complex and cardiovascular anomalies

    Energy Technology Data Exchange (ETDEWEB)

    Joy, H.M.; Barker, C.S. [Wessex Neurological Centre, Southampton (United Kingdom); Small, J.H. [Dept. of Radiology, Royal Bournemouth Hospital (United Kingdom); Armitage, M. [Bournemouth Diabetes and Endocrine Centre, Royal Bournemouth Hospital (United Kingdom)

    2001-01-01

    We present a case of trans-sphenoidal encephalomeningocele in association with a posterior cranial fossa malformation which fulfils the criteria for the Dandy-Walker complex. Congenital cardiovascular defects were also present. An abnormality of neural crest development may be responsible for the combined occurrence of these anomalies. (orig.)

  11. Outcome of Cushing's disease following transsphenoidal surgery in a single center over 20 years.

    LENUS (Irish Health Repository)

    Hassan-Smith, Zaki K

    2012-04-01

    Historically, Cushing\\'s disease (CD) was associated with a 5-yr survival of just 50%. Although advances in CD management have seen mortality rates improve, outcome from transsphenoidal surgery (TSS), the current first-line treatment, varies significantly between centers.

  12. Pre-operative assessment of patients undergoing endoscopic, transnasal, transsphenoidal pituitary surgery.

    Science.gov (United States)

    Lubbe, D; Semple, P

    2008-06-01

    To demonstrate the importance of pre-operative ear, nose and throat assessment in patients undergoing endoscopic, transsphenoidal surgery for pituitary tumours. Literature pertaining to the pre-operative otorhinolaryngological assessment and management of patients undergoing endoscopic anterior skull base surgery is sparse. We describe two cases from our series of 59 patients undergoing endoscopic pituitary surgery. The first case involved a young male patient with a large pituitary macroadenoma. His main complaint was visual impairment. He had no previous history of sinonasal pathology and did not complain of any nasal symptoms during the pre-operative neurosurgical assessment. At the time of surgery, a purulent nasal discharge was seen emanating from both middle meati. Surgery was abandoned due to the risk of post-operative meningitis, and postponed until the patient's chronic rhinosinusitis was optimally managed. The second patient was a 47-year-old woman with a large pituitary macroadenoma, who presented to the neurosurgical department with a main complaint of diplopia. She too gave no history of previous nasal problems, and she underwent uneventful surgery using the endoscopic, transnasal approach. Two weeks after surgery, she presented to the emergency unit with severe epistaxis. A previous diagnosis of hereditary haemorrhagic telangiectasia was discovered, and further surgical and medical intervention was required before the epistaxis was finally controlled. Pre-operative otorhinolaryngological assessment is essential prior to endoscopic pituitary or anterior skull base surgery. A thorough otorhinolaryngological history will determine whether any co-morbid diseases exist which could affect the surgical field. Nasal anatomy can be assessed via nasal endoscopy and sinusitis excluded. Computed tomography imaging is a valuable aid to decisions regarding additional procedures needed to optimise access to the pituitary fossa.

  13. Investigation of effectiveness of surgical treatment of chronic dacryocystitis - endonasal dacryocystorhinostomy

    Directory of Open Access Journals (Sweden)

    Borodulya V.L.

    2017-10-01

    Full Text Available Prolonged and conti­nuous lacrimation (symptom of epiphora causes discomfort, inclination to conjunctiva infect, reduces visual acuity and ultimately the quality of life of the patient. Despite the fact that there is a large number of various surgical interventions to restore tearing in patients with chronic dacryocystitis, the problem of lacrimation remains relevant. We have studied the operation of endonasal dacryocystorhinostomy and its long-term consequences. Surgical intervention in endonasal dacryocystorhinostomy is aimed at eliminating lacrimation by eliminating stenosis and forming a new combination of the cavity of the laryngeal canal with the nasal cavity, as well as the sanation of purulent foci of infection in the throat. There were 8 surgical interventions. Period of observation of patients in the postoperative period by ophthalmologist and ENT-doctor is from 1.5 to 2 years. The evaluation of the result was carried out in 6 months or more after the operation. A complete recovery with the recovery of the tear excretion in the nasal cavity has been achieved in all patients. The formed rhinostoma was wide, well functioning. Thus, endonasal dacryocystorhinostomy is a highly effective and should be a method of choice for inflammation of the lacrimal sac at any stage of development.

  14. Training to acquire psychomotor skills for endoscopic endonasal surgery using a personal webcam trainer.

    Science.gov (United States)

    Hirayama, Ryuichi; Fujimoto, Yasunori; Umegaki, Masao; Kagawa, Naoki; Kinoshita, Manabu; Hashimoto, Naoya; Yoshimine, Toshiki

    2013-05-01

    Existing training methods for neuroendoscopic surgery have mainly emphasized the acquisition of anatomical knowledge and procedures for operating an endoscope and instruments. For laparoscopic surgery, various training systems have been developed to teach handling of an endoscope as well as the manipulation of instruments for speedy and precise endoscopic performance using both hands. In endoscopic endonasal surgery (EES), especially using a binostril approach to the skull base and intradural lesions, the learning of more meticulous manipulation of instruments is mandatory, and it may be necessary to develop another type of training method for acquiring psychomotor skills for EES. Authors of the present study developed an inexpensive, portable personal trainer using a webcam and objectively evaluated its utility. Twenty-five neurosurgeons volunteered for this study and were divided into 2 groups, a novice group (19 neurosurgeons) and an experienced group (6 neurosurgeons). Before and after the exercises of set tasks with a webcam box trainer, the basic endoscopic skills of each participant were objectively assessed using the virtual reality simulator (LapSim) while executing 2 virtual tasks: grasping and instrument navigation. Scores for the following 11 performance variables were recorded: instrument time, instrument misses, instrument path length, and instrument angular path (all of which were measured in both hands), as well as tissue damage, max damage, and finally overall score. Instrument time was indicated as movement speed; instrument path length and instrument angular path as movement efficiency; and instrument misses, tissue damage, and max damage as movement precision. In the novice group, movement speed and efficiency were significantly improved after the training. In the experienced group, significant improvement was not shown in the majority of virtual tasks. Before the training, significantly greater movement speed and efficiency were demonstrated in

  15. Fatal antiphospholipid syndrome following endoscopic transnasal-transsphenoidal surgery for a pituitary tumor: A case report.

    Science.gov (United States)

    Li, Chiao-Zhu; Li, Chiao-Ching; Hsieh, Chih-Chuan; Lin, Meng-Chi; Hueng, Dueng-Yuan; Liu, Feng-Chen; Chen, Yuan-Hao

    2017-01-01

    The fatal type of antiphospholipid syndrome is a rare but life-threating condition. It may be triggered by surgery or infection. Endoscopic transnasal-transsphenoidal surgery is a common procedure for pituitary tumor. We report a catastrophic case of a young woman died of fatal antiphospholipid syndrome following endoscopic transnasal-transsphenoidal surgery. A 31-year-old woman of a history of stroke received endoscopic transnasal-transsphenoidal surgery for a pituitary tumor. The whole procedure was smooth. However, the patient suffered from acute delirium on postoperative day 4. Then, her consciousness became comatose state rapidly with dilatation of pupils. Urgent magnetic resonance imaging of brain demonstrated multiple acute lacunar infarcts. The positive antiphosphoipid antibody and severe thrombocytopenia were also noted. Fatal antiphospholipid syndrome was diagnosed. Plasma exchange, corticosteroids, anticoagulant agent were prescribed. The hemodynamic condition was gradually stable. However, the consciousness was still in deep coma. The patient died of organ donation 2 months later. If patients have a history of cerebral stroke in their early life, such as a young stroke, the APS and higher risk of developing fatal APS after major surgery should be considered. The optimal management of APS remains controversial. The best treatment strategies are only early diagnosis and aggressive therapies combing of anticoagulant, corticosteroid, and plasma exchange. The intravenous immunoglobulin is prescribed for patients with refractory APS.

  16. Assessment of frontal lobe sagging after endoscopic endonasal transcribriform resection of anterior skull base tumors: is rigid structural reconstruction of the cranial base defect necessary?

    Science.gov (United States)

    Eloy, Jean Anderson; Shukla, Pratik A; Choudhry, Osamah J; Singh, Rahul; Liu, James K

    2012-12-01

    The endoscopic endonasal transcribriform approach (EETA) is a viable alternative option for resection of selected anterior skull base (ASB) tumors. However, this technique results in the creation of large cribriform defects. Some have reported the use of a rigid substitute for ASB reconstruction to prevent postoperative frontal lobe sagging. We evaluate the degree of frontal lobe sagging using our triple-layer technique [fascia lata, acellular dermal allograft, and pedicled nasoseptal flap (PNSF)] without the use of rigid structural reconstruction for large cribriform defects. Retrospective analysis. Nine patients underwent an EETA for resection of large ASB tumors from August 2010 to November 2011. The degree of frontal lobe displacement after EETA, defined as the ASB position, was calculated based on the most inferior position of the frontal lobe relative to the nasion-sellar line defined on preoperative and postoperative imaging. A positive value signified upward displacement, and a negative value represented inferior displacement of the frontal lobe. The average cribriform defect size was 9.3 cm(2) (range, 5.0-13.8 cm(2) ). The average distance of postoperative frontal lobe displacement was 0.2 mm (range, -3.9 to 2.9 mm) without any cases of significant brain sagging. The mean follow-up period was 10.1 months (range, 4-19 months). There were no postoperative CSF leaks. Rigid structural repair may not be necessary for ASB defect repair after endoscopic endonasal resection of the cribriform plate. Our technique for multilayer cranial base reconstruction appears to be satisfactory in preventing delayed frontal lobe sagging. Copyright © 2012 The American Laryngological, Rhinological, and Otological Society, Inc.

  17. Sandwich technique using fibrin-coated collagen fleece for sellar reconstruction in large dural defects during transsphenoidal surgery.

    Science.gov (United States)

    So, Jaeyoung; Park, Hunho; Sung, Kyeong-Soo; Lee, Kyu Sung; Hong, Chang-Ki

    2017-09-01

    Various surgical methods to prevent intraoperative and postoperative cerebrospinal fluid (CSF) leaks during transsphenoidal approach (TSA) surgeries have been reported, but surgical techniques to address large dural defects have been less thoroughly investigated in the literature. The authors retrospectively evaluated the usefulness of the sandwich technique using fibrin-coated collagen fleece (TachoSil) to prevent intraoperative CSF leakage from large dural defects in TSA surgery. In total, 101 cases of intraoperative CSF leaks were observed among 465 patients who underwent TSA surgery at a single university hospital between 2002 and 2014. Among them, cases with Grade 3 intraoperative CSF leakages and large diaphragmatic/dural defects were reconstructed via the sandwich technique using TachoSil or via the conventional technique using simple intrasellar packing with fat or synthetic materials, and these cases were enrolled in this study. A total of 28 cases with Grade 3 intraoperative CSF leakages were identified and analyzed. The sandwich technique using TachoSil was applied in 13 cases, and the conventional technique was applied in 15 cases. The postoperative CSF leakage was significantly decreased by the sandwich technique as compared to the conventional technique (retrospectively, 0 cases vs. 4 cases (30.8%); P=0.044). The sandwich technique using TachoSil can effectively prevent CSF leakage in cases with large dural defects during TSA surgery. Copyright © 2017 Elsevier Ltd. All rights reserved.

  18. Successful endonasal dacryocystorhinostomy in a patient with Wegener’s granulomatosis

    Directory of Open Access Journals (Sweden)

    P Eloy

    2009-11-01

    Full Text Available P Eloy, E Leruth, B Bertrand, Ph RombauxENT and HNS department, Cliniques Universitaires de Mont-Godinne, Université Catholique de Louvain, 5530, Yvoir, BelgiumAbstract: Wegener’s granulomatosis (WG is one form of idiopathic autoimmune vasculitis. The disease has a predilection for the upper and lower respiratory tracts (lungs, nose, sinus, and kidneys. WG may be systemic, severe, and potentially lethal, but it may also be limited to the otolaryngological area or to the eyes and the orbits. Obstruction of the lacrimal pathway is a possible complication of the disease that affects approximately 7% of patients with WG. It usually occurs as a direct extension of sinonasal disease and typically is a late manifestation. Management of such a condition is generally viewed as difficult. We report the case of a patient with a quiescent WG limited to the otolaryngological area. This patient presented a bilateral obstruction of the nasolacrimal ducts caused by bilateral extensive adhesions in the nasal cavity. Because she had several episodes of left-side acute dacryocystitis which necessitated several courses of broad-spectrum antibiotics, she successfully underwent an endonasal endoscopic dacryocystorhinostomy using a diode laser and powered instrumentation. The authors describe the clinical case, the surgical technique, and review the literature.Keywords: Wegener’s granulomatosis, recurrent dacryocystitis, endonasal DCR, diode, laser, powered instrumentation

  19. Resident simulation training in endoscopic endonasal surgery utilizing haptic feedback technology.

    Science.gov (United States)

    Thawani, Jayesh P; Ramayya, Ashwin G; Abdullah, Kalil G; Hudgins, Eric; Vaughan, Kerry; Piazza, Matthew; Madsen, Peter J; Buch, Vivek; Sean Grady, M

    2016-12-01

    Simulated practice may improve resident performance in endoscopic endonasal surgery. Using the NeuroTouch haptic simulation platform, we evaluated resident performance and assessed the effect of simulation training on performance in the operating room. First- (N=3) and second- (N=3) year residents were assessed using six measures of proficiency. Using a visual analog scale, the senior author scored subjects. After the first session, subjects with lower scores were provided with simulation training. A second simulation served as a task-learning control. Residents were evaluated in the operating room over six months by the senior author-who was blinded to the trained/untrained identities-using the same parameters. A nonparametric bootstrap testing method was used for the analysis (Matlab v. 2014a). Simulation training was associated with an increase in performance scores in the operating room averaged over all measures (p=0.0045). This is the first study to evaluate the training utility of an endoscopic endonasal surgical task using a virtual reality haptic simulator. The data suggest that haptic simulation training in endoscopic neurosurgery may contribute to improvements in operative performance. Limitations include a small number of subjects and adjudication bias-although the trained/untrained identity of subjects was blinded. Further study using the proposed methods may better describe the relationship between simulated training and operative performance in endoscopic Neurosurgery. Copyright © 2016 Elsevier Ltd. All rights reserved.

  20. Endoscopic Endonasal Surgery for Remission of Cushing Disease Caused by Ectopic Intracavernous Macroadenoma: Case Report and Literature Review.

    Science.gov (United States)

    Koutourousiou, Maria; Winstead, Welby I

    2017-02-01

    Complete surgical resection of an adrenocorticotropic hormone (ACTH)-secreting pituitary adenoma is the gold standard of treatment of Cushing disease. Ectopic location of these adenomas is an extremely rare condition that may compromise the diagnosis and surgical success. We present the first case of an ectopic intracavernous ACTH-secreting macroadenoma totally resected with endoscopic endonasal surgery (EES). A 36-year-old woman presented with Cushing syndrome. Increased ACTH, serum cortisol, and free urine cortisol levels were identified; however, pituitary magnetic resonance imaging failed to show a pituitary tumor; instead, a parasellar lesion in the left cavernous sinus (CS) was noticed. Inferior petrosal sinus sampling showed a significant central to peripheral and lateralized left-sided ACTH gradient. The patient underwent EES. No tumor was found in the sella; however, the left CS was widely explored and a tumor was found lateral to the paraclival segment of the carotid artery. There were no complications after EES. Pathology confirmed the diagnosis of an ACTH-secreting adenoma. During the immediate postoperative course, serum cortisol levels decreased lower than 5 μg/dL. Postoperative magnetic resonance imaging showed complete tumor resection. At 20 months follow-up, the patient remained in clinical and biochemical remission of Cushing disease. Only 12 cases of ectopic intracavernous ACTH-secreting adenomas have been reported and all were microadenomas. The presence of an ectopic ACTH-secreting macroadenoma in the CS represents a surgical challenge. EES is the ideal approach for complete resection of ectopic intracavernous adenomas, allowing for a wide exploration of the CS with no surgical complications. Copyright © 2016 Elsevier Inc. All rights reserved.

  1. Bilateral endoscopic endonasal marsupialization of nasopalatine duct cyst

    Directory of Open Access Journals (Sweden)

    Yohei Honkura

    2015-02-01

    Full Text Available Nasopalatine duct cysts are the most common non-odontogenic cysts in the maxilla, and are conventionally treated through a sublabial or palatine approach. Recently, the endoscopic approach has been used, but experience is extremely limited. We treated a 29-year-old male with nasopalatine duct cyst by endoscopic marsupialization, but paresthesia of the incisor region occurred after surgery. This paresthesia gradually remitted within 6 months. The nasopalatine nerve, which innervates the upper incisor region, enters two lateral canals separately at the nasal floor and exits the central main canal at the palate. Damage to the bilateral nasopalatine nerves might lead to paresthesia, so we recommend careful examination for nerve fibers during endoscopic surgery, especially if fenestration is performed on both sides.

  2. Update on endoscopic endonasal resection of skull base meningiomas.

    Science.gov (United States)

    Brunworth, Joseph; Padhye, Vikram; Bassiouni, Ahmed; Psaltis, Alkis; Floreani, Stephen; Robinson, Simon; Santoreneos, Stephen; Vrodos, Nick; Parker, Andrew; Wickremesekera, Agadha; Wormald, Peter-John

    2015-04-01

    The objective of this work was to report success rates as well as potential obstacles in transnasal endoscopic resection of anterior skull base meningiomas. The study design was a case series with chart review at tertiary referral centers in South Australia and New Zealand. The patients were 37 consecutive patients who underwent endoscopic resection of skull-base meningiomas between 2004 and 2013. Review of patient charts and operative details were performed. Outcomes including complications are reported. Eighty-four percent of patients were women. There were 28 primary and 9 revision cases. Tumor locations were as follows: 14 olfactory groove/subfrontal; 12 planum/jugum sphenoidale; 7 tuberculum sellae; 3 clinoidal; and 1 clival. Vision change was the most common presenting symptom. Mean tumor volume was 33.68 cm(3) , mean diameter was 2.78 cm. Average operating times decreased with an initial learning curve and then plateaued. Primary tumors larger than 60 cm(3) took an average of 10 hours to resect. Gross total removal was achieved in 29 patients. There were no perioperative deaths. Two deaths occurred within 1 year of surgery. Postoperative cerebrospinal fluid (CSF) leaks occurred in 13 patients. Seventy-five percent of patients presenting with visual loss reported visual improvement. Of the 29 patients considered to have had complete resection at surgery, one was found to have residual disease on a postoperative magnetic resonance imaging (MRI) and another one later developed radiological evidence of recurrence. Using a 2-team approach, meningiomas of the skull base were successfully removed via an intranasal endoscopic technique. Although complete resection is typically possible even with large tumors, the lengthy resection required time for tumors larger than 60 cm(3) (diameter ≥4 cm) may obviate some of the advantages of this approach. The rate of postoperative CSF leak decreases when a synthetic dural substitute is added but does not approach zero.

  3. MRI Findings of Causalgia of the Lower Extremity Following Transsphenoidal Resection of Pituitary Tumor

    Directory of Open Access Journals (Sweden)

    D. Ryan Ormond

    2012-01-01

    Full Text Available Background. Causalgia is continuing pain, allodynia, or hyperalgesia after nerve injury with edema, changes in skin blood flow, or abnormal sudomotor activity. Here we report a case of lower extremity causalgia following elective transsphenoidal resection of a pituitary tumor in a young man. Clinical Presentation. A 33-year-old man with acromegaly underwent elective sublabial transsphenoidal resection of his pituitary tumor. During the three-hour surgery, the lower limbs were kept in a supine, neutral position with a pillow under the knees. The right thigh was slightly internally rotated with a tape to expose fascia lata, which was harvested to repair the sella. Postoperatively, he developed causalgia in a distal sciatic and common peroneal nerve distribution. Pain was refractory to several interventions. Finally, phenoxybenzamine improved his pain significantly. Conclusions. Malpositioning in the operating room resulted in causalgia in this young man. Phenoxybenzamine improved, and ultimately resolved, his symptoms. Improvement in his pain symptoms correlated with resolution of imaging changes in the distal sciatic and peroneal nerves on the side of injury.

  4. Postoperative follow-up of pituitary adenomas after trans-sphenoidal resection: MRI and clinical correlation

    International Nuclear Information System (INIS)

    Rodriguez, O.; Mateos, B.; Pedraja, R. de la; Villoria, R.; Hernando, J.I.; Pastor, A.; Pomposo, I.; Aurrecoechea, J.

    1996-01-01

    Our purpose was to correlate the morphological changes seen on MRI studies of the sellar region after trans-sphenoidal resection of pituitary adenomas with clinical and hormonal studies. Between January 1993 and March 1994, 16 patients with a pituitary adenoma (9 macroadenomas and 7 microadenomas) were subjected to trans-sphenoidal resection and included in a prospective study. The protocol consisted of MRI, hormonal and visual studies at the following times: immediately postoperative (1st week), 1st month, 4th month and 1st year after surgery. The evolution of the contents of the sella turcica (tumour remnant, packing material and gland tissue), effects on the infundibulum, optic chiasm, cavernous sinus and sphenoid sinus were correlated with the clinical and hormonal studies. Stabilisation of the postsurgical changes occurred by the 4th month. Tumour remnants were noted in the immediate postoperative period in macroadenomas. Compression of the infundibulum was the only reliable indicator of possible involvement. Optic chiasm compression, defined as close contact between the chiasm and the tumour, was the only morphological finding that indicated visual impairment. There was no standard repneumatisation pattern in the sphenoid sinus, since mucosal changes resembling sinusitis were one of the postsurgical changes. We found MRI not to be useful for follow-up of microadenomas. (orig.). With 4 figs., 4 tabs

  5. Postoperative follow-up of pituitary adenomas after trans-sphenoidal resection: MRI and clinical correlation

    Energy Technology Data Exchange (ETDEWEB)

    Rodriguez, O. [Servicio de Radiologia, Hospital de Cruces, Baracaldo (Spain); Mateos, B. [Servicio de Radiologia, Hospital de Cruces, Baracaldo (Spain); Pedraja, R. de la [Servicio de Endocrinologia, Hospital de Cruces, Baracaldo (Spain); Villoria, R. [Servicio de Radiologia, Hospital de Cruces, Baracaldo (Spain); Hernando, J.I. [Servicio de Radiologia, Hospital de Cruces, Baracaldo (Spain); Pastor, A. [Servicio de Radiologia, Hospital de Cruces, Baracaldo (Spain); Pomposo, I. [Servicio de Neurocirugia, Hospital de Cruces, Baracaldo (Spain); Aurrecoechea, J. [Servicio de Neurocirugia, Hospital de Cruces, Baracaldo (Spain)

    1996-11-01

    Our purpose was to correlate the morphological changes seen on MRI studies of the sellar region after trans-sphenoidal resection of pituitary adenomas with clinical and hormonal studies. Between January 1993 and March 1994, 16 patients with a pituitary adenoma (9 macroadenomas and 7 microadenomas) were subjected to trans-sphenoidal resection and included in a prospective study. The protocol consisted of MRI, hormonal and visual studies at the following times: immediately postoperative (1st week), 1st month, 4th month and 1st year after surgery. The evolution of the contents of the sella turcica (tumour remnant, packing material and gland tissue), effects on the infundibulum, optic chiasm, cavernous sinus and sphenoid sinus were correlated with the clinical and hormonal studies. Stabilisation of the postsurgical changes occurred by the 4th month. Tumour remnants were noted in the immediate postoperative period in macroadenomas. Compression of the infundibulum was the only reliable indicator of possible involvement. Optic chiasm compression, defined as close contact between the chiasm and the tumour, was the only morphological finding that indicated visual impairment. There was no standard repneumatisation pattern in the sphenoid sinus, since mucosal changes resembling sinusitis were one of the postsurgical changes. We found MRI not to be useful for follow-up of microadenomas. (orig.). With 4 figs., 4 tabs.

  6. Incidence, risk factors and management of severe post-transsphenoidal epistaxis.

    Science.gov (United States)

    De Los Reyes, Kenneth M; Gross, Bradley A; Frerichs, Kai U; Dunn, Ian F; Lin, Ning; Rincon-Torroella, Jordina; Annino, Donald J; Laws, Edward R

    2015-01-01

    Among the major complications of transsphenoidal surgery, less attention has been given to severe postoperative epistaxis, which can lead to devastating consequences. In this study, we reviewed 551 consecutive patients treated over a 4 year period by the senior author to evaluate the incidence, risk factors, etiology and management of immediate and delayed post-transsphenoidal epistaxis. Eighteen patients (3.3%) developed significant postoperative epistaxis - six immediately and 12 delayed (mean postoperative day 10.8). Fourteen patients harbored macroadenomas (78%) and 11 of 18 (61.1%) had complex nasal/sphenoid anatomy. In the immediate epistaxis group, 33% had acute postoperative hypertension. In the delayed group, one had an anterior ethmoidal pseudoaneurysm, and one had restarted anticoagulation on postoperative day 3. We treated the immediate epistaxis group with bedside nasal packing followed by operative re-exploration if conservative measures were unsuccessful. The delayed group underwent bedside nasal hemostasis; if unsuccessful, angiographic embolization was performed. After definitive treatment, no patients had recurrent epistaxis. Copyright © 2014 Elsevier Ltd. All rights reserved.

  7. Late Onset of CSF Rhinorrhea in a Postoperative Transsphenoidal Surgery Patient Following Robotic-Assisted Abdominal Hysterectomy

    Directory of Open Access Journals (Sweden)

    Justin T. Dowdy MD

    2014-01-01

    Full Text Available Cerebrospinal fluid (CSF leak is the most commonly encountered perioperative complication in transsphenoidal surgery for pituitary lesions. Direct closure with a combination of autologous fat, local bone, and/or synthetic grafts remains the standard of care for leaks encountered at the time of surgery as well as postoperatively. The development of the vascularized nasoseptal flap as a closure technique has increased the surgeon’s capacity to correct even larger openings in the dura of the sella as well as widely exposed anterior skull base defects. Yet these advances in the technical nuances for management of post-transsphenoidal CSF leak are useless without the ability to recognize a CSF leak by physical examination, clinical history, biochemical testing, or radiographic assessment. Here, we report a case of a patient who developed a CSF leak 28 years after transsphenoidal surgery, precipitated by a robotic-assisted hysterectomy during which increased intra-abdominal pressure and steep Trendelenberg positioning were both factors. Given the remote nature of the patient’s transsphenoidal surgery and relative paucity of data regarding such a complication, the condition went unrecognized for several months. We review the available literature regarding risk and pathophysiology of CSF leak following abdominal surgery and propose the need for increased vigilance in identification of such occurrences with the increasing acceptance and popularity of minimally invasive abdominal and pelvic surgeries as standards in the field.

  8. The Prognostic Value of Perioperative Profiles of ACTH and Cortisol for Recurrence after Transsphenoidal Hypophysectomy in Dogs with Corticotroph Adenomas

    NARCIS (Netherlands)

    van Rijn, S J; Hanson, J M; Zierikzee, D; Kooistra, H S; Penning, L C; Tryfonidou, M A; Meij, B P

    2015-01-01

    BACKGROUND: Transsphenoidal hypophysectomy is an effective treatment for dogs with pituitary-dependent hypercortisolism (PDH). However, long-term recurrence of hypercortisolism is a well-recognized problem, indicating the need for reliable prognostic indicators. OBJECTIVES: The aim of this study was

  9. Required Reading: The Most Impactful Articles in Endoscopic Endonasal Skull Base Surgery.

    Science.gov (United States)

    Zhang, Michael; Singh, Harminder; Almodovar-Mercado, Gustavo J; Anand, Vijay K; Schwartz, Theodore H

    2016-08-01

    Endoscopic endonasal skull base surgery has become widely accepted in neurosurgery and otolaryngology over the last 15 years. However, there has yet to be a formal curation of the most impactful articles for an introductory curriculum to its technical evolution. The Science Citation Index Expanded was used to generate a citation rank list (October 2015) on articles relevant to endoscopic skull base surgery. The top 35 cited articles overall, as well as the top 15 since 2009, were identified. Journal, year, author, study population, article format, and level of evidence were compiled. Additional surgeon experts were polled and made recommendations for significant contributions to the literature. The top 35 publications ranged from 98 to 467 citations and were published in 10 different journals. Four articles had more than 250 citations. A period of frequent contribution occurred between 2005 and 2009, when 21/35 reports were published. 18/35 articles were case series, and 13/35 were technical reports. There were 11/35 articles focused primarily on pituitary surgery and 10/35 on extrasellar lesions. The top 15 articles since 2009 had 8/15 articles focused on extrasellar lesions. Polled surgeons consistently identified the most prominently cited articles, and their recommendations drew attention to cerebrospinal fluid leak as well as extrasellar management. Identification of the most cited works within endoscopic endonasal skull base surgery shows greater anatomic access and safety over the last 2 decades. These articles can serve as an educational tool for novices or midlevel practitioners wishing to obtain a greater understanding of the field. Copyright © 2016 Elsevier Inc. All rights reserved.

  10. СOMPARATIVE EFFICIENCY OF USE OF METHYLETHYLPYRIDINOL BY THE ENDONASAL ELECTROPHORESIS AND PARABULBAR INJECTIONS AT THE CHORIORETINAL DYSTROPHY

    Directory of Open Access Journals (Sweden)

    A. M. Razumovskaya

    2017-01-01

    Full Text Available Research objective: comparative assessment of efficiency of use of Emoxypin® by an endonasal electrophoresis and parabulbar injections at a chorioretinal dystrophy. Methods: 71 patients (average age of 55±3 years suffering from a chorioretinal dystrophy of various genesis were in the study. The ophthalmologic examination included: evaluation of visual acuity, a field of vision, a visual fatigue, a condition of bulbar microcirculation (the general conjunctiva index. Besides, electrophysiological examination was conducted, including critical frequency of merge of flickers and electric sensitivity of an eye. The patients were divided into 2 groups. The main group (28 patients received Emoxypin® with endonasal electrophoresis and group B (43 patients received Emoxypin® by parabulbar injections. Results: Results of the statistical analysis in both groups showed visual acuity increasment, expansion of borders of a field of vision, depression of visual fatigability, indicators of electrophysiological examination and bulbar microcirculation improved. Conclusion: The comparative assessment of efficiency of use of Emoxypin® by an endonasal electrophoresis and parabulbar injections at a chorioretinal dystrophic various a genesis showed appreciable medical effect in the course of restoration of visual functions which in some cases (18% even better effect observed at parabulbar injections.

  11. Intra- and inter-rater reliability of endonasal activity estimation in granulomatosis with polyangiitis (Wegener´s).

    Science.gov (United States)

    Garske, Ulrike; Haack, Andrea; Beltrán, Olga; Flores-Suárez, Louis F; Bremer, Jan P; Lamprecht, Peter; Hedderich, Jürgen; Quetz, Joachim; Gross, Wolfgang L; Ambrosch, Petra; Laudien, Martin

    2012-01-01

    Granulomatosis with polyangiitis (GPA) frequently starts with an affection of the nasal and paranasal mucosa. Localised GPA of the nasal mucosa or persistent disease activity ('grumbling disease') is often encountered even under immunosuppressive therapy. Necessity for reconstructive surgery is common and careful scheduling to prevent failure and minimise revision rates is crucial. Therefore, reliable estimation of GPA activity in the upper airways using a score is mandatory for diagnosis, follow-up and scheduling reconstructive surgery. Fifty endoscopic, endonasal images of 45 patients with GPA were used. Twelve (4 German, 8 Mexican) experienced (n=7) and inexperienced (n=5) physicians assessed GPA-activity at two times (T1/T2) in dichotomy and in a grading approach (none, mild, moderate and high activity) using the novel ENT Activity Score (ENTAS). All documents were written in English. Estimation of activity in dichotomy (none vs. mild/moderate/high): Cohen's Kappa (κ) for intra-rater reliability T1/T2 in inexperienced and experienced physicians was κ=0.58 (agreement 85%) and κ=0.72 (agreement 91%). The inter-rater reliability (Fleiss's κ) T1/T2 for inexperienced and experienced physicians was κ=0.62/κ=0.59 and κ=0.50/κ=0.58 respectively. Estimation of activity in grading approach (none, mild, moderate, high): for inexperienced physicians the intra-rater reliability T1/T2 was κ=0.67 (agreement 56%) and the inter-rater reliability at T1/T2 was κ=0.29 (intraclass correlation coefficient, ICC=0.69) and κ=0.27 (ICC=0.59). For experienced physicians the intra-rater reliability T1/T2 was κ=0.80 (agreement 67%) and the inter-rater reliability at T1 and T2 was κ=0.41 (ICC=0.77) and κ=0.39 (ICC=0.75) respectively. Intra-rater reliability is high in decision in dichotomy and even in grading activity. There is no difference for experienced or inexperienced physicians. Inter-rater reliability is high in dichotomy, but low for activity grading. Thus, the ENTAS

  12. Outcome of Microscopic Transsphenoidal Surgery in Cushing Disease: A Case Series of 96 Patients.

    Science.gov (United States)

    Shirvani, Manochehr; Motiei-Langroudi, Rouzbeh; Sadeghian, Homa

    2016-03-01

    To analyze the results of transsphenoidal surgery in patients with Cushing disease and outcome. Retrospective analysis of the records of 96 patients with Cushing disease from 1997 to 2012. There were 73 females and 23 males, with a mean follow-up of 44 months (range, 3-13 years). The sex ratio was significantly different in children and teenagers versus adults. Magnetic resonance imaging showed microadenoma, macroadenoma, and no adenoma in 66, 18, and 12 patients, respectively. There was no surgical mortality. Early remission (normal 24-hour urinary free cortisol and basal serum cortisol Cushing disease. Macroadenomas, cavernous sinus invasion, and harder tumor consistencies, however, are associated with lower remission rates (higher disease persistence) and younger age, higher preoperative cortisol levels, and longer follow-up periods are associated with higher recurrence. Copyright © 2016 Elsevier Inc. All rights reserved.

  13. [Results of trans-sphenoidal surgery for the treatment of acromegaly].

    Science.gov (United States)

    Pumar, A; Santos, C; García-Luna, P P; Acosta, D; Pereira, J L; Gavilán, I; Leal-Cerro, A; Astorga, R

    1991-02-01

    During the past 17 years (1972-89) 55 transsphenoidal surgery (TSS) interventions were performed in our Hospital in 53 cases of acromagaly (2 cases underwent surgery twice). 22 were cured (40%); 15 partial efficacy (27%) and 18 negative efficacy (33%). Mean GH values (ngr/ml) before surgery were: Cured cases 15.8 + 12.9 (p = 0.0015). Basal GH values above 40 ngr/ml obscure the prognosis of TSS in acromegaly. Cure was perfectly achieved in smaller size hypophysis adenomas (Hardy Grade land 11 in CT scan). The complications in the early post-surgery were rare and transient. Chronic sequelae due to TSS occurred in 7 cases (13.5%), as complete or partial anterior hypophysis failure. TSS is the treatment of choice of acromegaly in our environment, however a significant number of cases do not achieve cure and need to complete treatment with hypophyseal radiotherapy.

  14. Inpatient Complications After Transsphenoidal Surgery in Cushing's Versus Non-Cushing's Disease Patients.

    Science.gov (United States)

    Svider, Peter F; Raikundalia, Milap D; Pines, Morgan J; Baredes, Soly; Folbe, Adam J; Liu, James K; Eloy, Jean Anderson

    2016-01-01

    Transsphenoidal surgery (TSS) harbors a potential for hypopituitarism, cerebrospinal fluid (CSF) leaks, and other complications. We utilized the Nationwide Inpatient Sample Database (NIS) to compare inpatient complication rates between Cushing's disease (CD) and non-Cushing's disease (NCD) patients undergoing TSS. Inpatient hospitalization data for 960 CD and 12 110 NCD patients who underwent TSS between 2002 and 2010 were accessed. Demographic information, outcomes, and complication rates were evaluated. Patients with CD had a female predilection (81.7%) and were younger (40.5 ± 14.4 years) than NCD patients (47.8% female; 52.1 ± 16.3 years) (P iatrogenic pituitary disorders overall. No differences were noted in the rate of early CSF leaks between postoperative TSS CD and NCD patients. Postoperative diabetes insipidus did not significantly differ between groups after adjusting for confounders. Only odds of urinary/renal complications in CD patients was significant after adjustment. © The Author(s) 2015.

  15. Visual Fields at Presentation and after Trans-sphenoidal Resection of Pituitary Adenomas

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    Renu Dhasmana

    2011-01-01

    Full Text Available Purpose: To evaluate visual field changes in patients with pituitary adenomas following trans-sphenoidal surgery. Methods: Eighteen patients with pituitary adenomas underwent a complete ophthalmic assessment and visual field analysis using the Humphrey Field Analyzer 30-2 program before and after trans-sphenoidal surgical resection at the Himalayan Institute of Medical Sciences over a one year period. Visual acuity, duration of symptoms, optic nerve head changes, pattern of visual field defects, and variables such as mean deviation and visual field index were compared. Results: Thirty-six eyes of 18 patients including 10 male and 8 female subjects with mean age of 35.1±9.9 years and histologically proven pituitary adenoma were included. Mean visual acuity at presentation was 0.29 logMAR which improved to 0.21 logMAR postoperatively (P = 0.305. Of 36 eyes, 24 (66.7% had visual field defects including temporal defects in 12 eyes (33.3%, non-specific defects in 10 eyes (27.8%, and peripheral field constriction in 2 eyes (5.6%. Mean deviation of visual fields at presentation was -14.28 dB which improved to -11.32 dB postoperatively. The visual field index improved from 63.5% to 75% postoperatively. Favorable visual field outcomes were correlated with shorter duration of symptoms and absence of optic nerve head changes at presentation. Conclusion: Visual field defects were present in two thirds of patients at presentation. An overall improvement in vision and visual fields was noted after surgical resection. An inverse correlation was found between the duration of symptoms and postoperative visual field recovery, signifying the importance of early surgical intervention.

  16. Late Onset of CSF Rhinorrhea in a Postoperative Transsphenoidal Surgery Patient Following Robotic-Assisted Abdominal Hysterectomy

    OpenAIRE

    Dowdy, Justin T.; Moody, Marcus W.; Cifarelli, Christopher P.

    2014-01-01

    Cerebrospinal fluid (CSF) leak is the most commonly encountered perioperative complication in transsphenoidal surgery for pituitary lesions. Direct closure with a combination of autologous fat, local bone, and/or synthetic grafts remains the standard of care for leaks encountered at the time of surgery as well as postoperatively. The development of the vascularized nasoseptal flap as a closure technique has increased the surgeon’s capacity to correct even larger openings in the dura of the se...

  17. Coagulative and ablative characteristics of a novel diode laser system (1470nm) for endonasal applications

    Science.gov (United States)

    Betz, C. S.; Havel, M.; Janda, P.; Leunig, A.; Sroka, R.

    2008-02-01

    Introduction: Being practical, efficient and inexpensive, fibre guided diode laser systems are preferable over others for endonasal applications. A new medical 1470 nm diode laser system is expected to offer good ablative and coagulative tissue effects. Methods: The new 1470 nm diode laser system was compared to a conventional 940 nm system with regards to laser tissue effects (ablation, coagulation, carbonization zones) in an ex vivo setup using fresh liver and muscle tissue. The laser fibres were fixed to a computer controlled stepper motor, and the light was applied using comparable power settings and a reproducible procedure under constant conditions. Clinical efficacy and postoperative morbidity was evaluated in two groups of 10 patients undergoing laser coagulation therapy of hyperplastic nasal turbinates. Results: In the experimental setup, the 1470 nm laser diode system proved to be more efficient in inducing tissue effects with an energy factor of 2-3 for highly perfused hepatic tissue to 30 for muscular tissue. In the clinical case series, the higher efficacy of the 1470 nm diode laser system led to reduced energy settings as compared to the conventional system with comparable clinical results. Postoperative crusting was less pronounced in the 1470 nm laser group. Conclusion: The 1470 nm diode laser system offers a highly efficient alternative to conventional diode laser systems for the coagulation of hyperplastic nasal turbinates. According to the experimental results it can be furthermore expected that it disposes of an excellent surgical potential with regards to its cutting abilities.

  18. Effectiveness of Synthetic Polyurethane Foam as a Nasal Packing Material in Endoscopic Endonasal Dacryocystorhinostomy.

    Science.gov (United States)

    Lee, Joonsik; Lee, Hwa; Lee, Hyun Kyu; Chang, Minwook; Park, Minsoo; Baek, Sehyun

    2015-10-01

    To compare the effects of 2 nasal packing materials, synthetic polyurethane foam (absorbable) and expandable polyvinyl acetate (nonabsorbable), on the surgical success rate and postoperative complications after endoscopic endonasal dacryocystorhinostomy (EDCR). A retrospective medical review of 459 patients (580 eyes) who underwent EDCR for primary acquired nasolacrimal duct obstruction at Korea University Guro Hospitals from January 2009 to February 2014. Surgical success rate (anatomical, functional), postoperative complications (granuloma, synechia, bleeding, and infection) were compared between the 2 groups, absorbable (318 eyes) and nonabsorbable (262 eyes). The absorbable group showed better results in surgical success rate regarding anatomical (90.5% versus 76.3%, P = 0.00) and functional (89.3% versus 75.9%, P = 0.00). Granulomas developed less frequently in the absorbable group (24.5% versus 38.9%, P = 0.00). Also, bleeding and crust were less frequent in the absorbable group (P = 0.00). Infections were less frequent in the nonabsorbable group (1.52%) compared with the absorbable group (7.86%, P = 0.00). The rate of revision surgery was lower in the absorbable group (7.86% versus 20.9%, P = 0.00). As for the influence of secondary outcomes to the surgical success by multiple logistic regression, granulomas had the largest effect on surgical success either anatomical or functional (odds ratio = 82.393 to anatomical and 44.058 to functional). Synechia had the second largest effect on surgical success (odds ratio = 11.897 to anatomical and 9.605 to functional). The authors suggest that using a synthetic polyurethane foam as a nasal packing material is not only a surgical option, but also a crucial and essential procedure in EDCR.

  19. Endonasal endoscopic repair of anterior skull-base fistulas: the Kuala Lumpur experience.

    Science.gov (United States)

    Gendeh, B S; Mazita, A; Selladurai, B M; Jegan, T; Jeevanan, J; Misiran, K

    2005-11-01

    The purpose of this retrospective study is to determine the pattern of cerebrospinal fluid (CSF) rhinorrhoea presenting to our tertiary referral centre in Kuala Lumpur and to assess the clinical outcomes of endonasal endoscopic surgery for repair of anterior skull base fistulas. Sixteen patients were treated between 1998 and 2004. The aetiology of the condition was spontaneous in seven and acquired in nine patients. In the acquired category, three patients had accidental trauma and this was iatrogenic in six patients (five post pituitary surgery), with one post endoscopic sinus surgery (ESS). Imaging included computed tomography (CT) scan and magnetic resonance imaging (MRI). Endoscopic repair is less suited for defects in the frontal sinuses with prominent lateral extension and defects greater than 1.5 cm in diameter involving the skull base. Fascia lata, middle turbinate mucosa, nasal perichondrium and ear fat ('bath plug') were the preferred repair materials in the anterior skull base, whereas fascia lata, cartilage and abdominal fat obliteration was preferentially used in the sphenoid leak repair. Intrathecal sodium flourescein helped to confirm the site of CSF fistula in 81.3 per cent of the patients. Ninety per cent of the patients who underwent 'bath plug' repair were successful. The overall success rate for a primary endoscopic procedure was 87.5 per cent, although in two cases a second endoscopic procedure was required for closure. In the majority of cases endoscopic repair was successful, and this avoids many of the complications associated with craniotomy, particularly in a young population. Therefore it is our preferred option, but an alternative procedure should be utilized should this prove necessary.

  20. Xanthomatous Hypophysitis Presenting with Diabetes Insipidus Completely Cured Through Transsphenoidal Surgery: Case Report and Literature Review.

    Science.gov (United States)

    Lin, Wei; Gao, Lu; Guo, Xiaopeng; Wang, Wenze; Xing, Bing

    2017-08-01

    Xanthomatous hypophysitis (XH) is extremely rare. Only 27 cases have been reported in the literature. No XH patient presenting with diabetes insipidus (DI) has been completely cured through surgery. Here, we describe the first XH case of a DI patient whose pituitary function was normalized postoperatively, without hormone replacement therapy. A 41-year-old woman suffered from polydipsia, DI, headache, and breast discharge. Laboratory investigation revealed hyperprolactinemia. Pituitary magnetic resonance imaging showed a 2.0-cm × 1.4-cm × 1.6-cm lesion that demonstrated heterogeneous intensity on T1-weighted imaging and peripheral ring enhancement following contrast; the lesion was totally removed through transsphenoidal surgery. Histopathologic and immunohistochemical examinations confirmed the diagnosis of XH. At the 4- and 15-month follow-up visits, all pituitary-related hormones were normal, and the patient was not taking medication. A repeat pituitary magnetic resonance imaging showed no evidence of recurrence. To the best of our knowledge, this case is the first documented occurrence of XH with DI completely cured through surgery. If XH is suspected, total surgical resection of the lesion is recommended and normal pituitary tissue should be carefully protected intraoperatively. Copyright © 2017 Elsevier Inc. All rights reserved.

  1. Results of repeated transsphenoidal surgery in Cushing's disease. Long-term follow-up.

    Science.gov (United States)

    Valderrábano, Pablo; Aller, Javier; García-Valdecasas, Leopoldo; García-Uría, José; Martín, Laura; Palacios, Nuria; Estrada, Javier

    2014-04-01

    Transsphenoidal surgery (TSS) is the treatment of choice for Cushing's disease (CD). However, the best treatment option when hypercortisolism persists or recurs remains unknown. The aim of this study was to analyze the short and long-term outcome of repeat TSS in this situation and to search for response predictors. Data from 26 patients with persistent (n=11) or recurrent (n=15) hypercortisolism who underwent repeat surgery by a single neurosurgeon between 1982 and 2009 were retrospectively analyzed. Remission was defined as normalization of urinary free cortisol (UFC) levels, and recurrence as presence of elevated UFC levels after having achieved remission. The following potential outcome predictors were analyzed: adrenal status (persistence or recurrence) after initial TSS, tumor identification in imaging tests, degree of hypercortisolism before repeat TSS, same/different surgeon in both TSS, and time to repeat surgery. Immediate postoperative remission was achieved in 12 patients (46.2%). Five of the 10 patients with available follow-up data relapsed after surgery (median time to recurrence, 13 months). New hormone deficiencies were seen in seven patients (37%), and two patients had cerebrospinal fluid leakage. No other major complications occurred. None of the preoperative factors analyzed was predictive of surgical outcome. When compared to initial surgery, repeat TSS for CD is associated to a lower remission rate and a higher risk of recurrence and complications. Further studies are needed to define outcome predictors. Copyright © 2013 SEEN. Published by Elsevier Espana. All rights reserved.

  2. Central diabetes insipidus after transsphenoidal surgery in dogs with Cushing's disease.

    Science.gov (United States)

    Teshima, Takahiro; Hara, Yasushi; Taoda, Takahiro; Teramoto, Akira; Tagawa, Masahiro

    2011-01-01

    Transsphenoidal surgery (TSS) is an effective treatment for canine Cushing's disease, as well as human Cushing's disease. In humans, only the pituitary adenoma tissue is resected by TSS. However, in dogs, the whole pituitary including normal tissue is resected. Hence, central diabetes insipidus (CDI) may complicate the postoperative course in almost all dogs with Cushing's disease treated by TSS. However, it is difficult to assess the duration of the postoperative CDI, and whether it may be transient or permanent. In this study, postoperative CDI in 21 dogs with Cushing's disease and its predicted prognosis by preoperative parameters was investigated. In this study, CDI after TSS was classified as either transient or permanent based on the requirement for desmopressin. Preoperative circulating serum cortisol concentrations and pre- and post-operative plasma AVP concentrations were not significantly different between the transient CDI dogs and permanent CDI dogs. The duration of postoperative CDI was not correlated to the signal intensity ratio (posterior lobe of the pituitary/cerebral cortex), which is obtained from preoperative magnetic resonance imaging (MRI). However, the pituitary height/brain area (P/B) ratio of the permanent CDI dogs was significantly greater than that of the transient CDI dogs. In addition, there was a significant difference between the enlarged-pituitary (P/B ratio > 0.31) transient CDI dogs and the permanent CDI dogs. These results suggest that the incidence of postoperative permanent CDI is strongly influenced by the pituitary size.

  3. Clinical and endocrinological evaluation of 16 acromegalic patients treated by transsphenoidal surgery.

    Science.gov (United States)

    Leavens, M E; Samaan, N A; Jesse, R H; Byers, R M

    1977-12-01

    Sixteen patients with acromegaly treated with transsphenoidal pituitary surgery were evaluated with the measurement of serum human growth hormone (HGH) before and after intravenous stimulation with thyrotropin-releasing hormone (TRH). Fourteen of these patients showed a significant rise of serum HGH after TRH stimulation before surgery. After surgery, 12 patients with Grade 2 noninvasive adenomas had normal fasting serum HGH levels which did not stimulate with TRH. Two of these patients showed high serum HGH levels both at fasting and after TRH stimulation and required a second operation to remove residual adenoma within the sella before adequate lowering of HGH was achieved. Evidence of recurrent adenoma has not occurred clinically or biochemically in this group of 12 patients followed for an average of 24 months (2 to 60 months). The results were unsatisfactory in four of these 16 patients. One patient who has a postoperative HGH of 9 ng/ml which still stimulates with TRH has made clinical improvement, but must have residual adenoma in the sella or invasive adenoma in the dura and tumor capsule. Additional treatment with irradiation has been given. Failure to achieve satisfactory results in the other three patients was attributed to the presence of locally invasive adenoma; one in the sphenoid sinus, and the other two possibly as a consequence of previous operative procedures.

  4. Comparison of hemodynamic effects of epinephrine (1:200000 infiltration with or without lignocaine in endonasal endoscopic dacryocystorhinostomy

    Directory of Open Access Journals (Sweden)

    Afroz Khan

    2016-01-01

    Full Text Available Background Obtaining adequate hemostasis is of utmost importance during surgery to improve the surgical field. Aims and Objectives The objective of this study is to determine the hemodynamic and haemostatic effects of same concentration of epinephrine with or without local anesthetic used during Endonasal Endoscopic Dacryocystorhinostomy (EE-DCR. Material and Methods Prospective, randomized study was undertaken on sixty patients selected for endonasal endoscopic dacryocystorhinostomy under general anaesthesia. Group A received 8-10ml of epinephrine 1:200,000 with Lidocaine and Group B received 8-10ml of epinephrine 1:200,000 with normal saline. Results In our study we found a statistically significant increase in SBP, DBP, MAP, HR from baseline value in group B with the value reaching a peak at around 5 min and then the parameters start normalizing towards baseline over several minutes. Whereas in case of group A patients, there was no significant changes in baseline values except a mild decrease in all parameters including SBP, DBP, MAP and HR. Conclusions The quality of surgical field was comparable in both groups without any significant differences. Addition of lignocaine to the epinephrine attenuates the cardiovascular side effects of epinephrine without affecting the visualization of the surgical field.

  5. The prognostic value of perioperative profiles of ACTH and cortisol for recurrence after transsphenoidal hypophysectomy in dogs with corticotroph adenomas.

    Science.gov (United States)

    van Rijn, S J; Hanson, J M; Zierikzee, D; Kooistra, H S; Penning, L C; Tryfonidou, M A; Meij, B P

    2015-01-01

    Transsphenoidal hypophysectomy is an effective treatment for dogs with pituitary-dependent hypercortisolism (PDH). However, long-term recurrence of hypercortisolism is a well-recognized problem, indicating the need for reliable prognostic indicators. The aim of this study was to evaluate the prognostic value of perioperative plasma ACTH and cortisol concentrations for identifying recurrence of hypercortisolism after transsphenoidal hypophysectomy. A total of 112 dogs with PDH that underwent transsphenoidal hypophysectomy met the inclusion criteria of the study. Hormone concentrations were measured preoperatively and 1-5 hours after surgery. Both absolute hormone concentrations and postoperative concentrations normalized to preoperative concentrations were included in analyses. The prognostic value of hormone concentrations was studied with Cox's proportional hazard analysis. Median follow-up and disease-free period were 1096 days and 896 days, respectively. Twenty-eight percent of patients had recurrence, with a median disease-free period of 588 days. Both absolute and normalized postoperative cortisol concentrations were significantly higher in dogs with recurrence than in dogs without recurrence. High ACTH 5 hours after surgery, high cortisol 1 and 4 hours after surgery, high normalized ACTH 3 hours after surgery, high normalized cortisol 4 hours after surgery and the random slope of cortisol were associated with a shorter disease-free period. Individual perioperative hormone curves provide valuable information about the risk of recurrence after hypophysectomy. However, because no single cutoff point could be identified, combination with other variables, such as the pituitary height/brain area (P/B) ratio, is still needed to obtain a good estimate of the risk for recurrence of hypercortisolism after hypophysectomy. Copyright © 2015 The Authors. Journal of Veterinary Internal Medicine published by Wiley Periodicals, Inc. on behalf of the American College of

  6. Factors influencing improvement of visual field after trans-sphenoidal resection of pituitary macroadenomas: a retrospective cohort study

    Directory of Open Access Journals (Sweden)

    Fen-Fen Yu

    2015-12-01

    Full Text Available To investigate the influencing factors of visual field improvement after trans-sphenoidal resection of pituitary macroadenomas. This retrospective cohort study included 201 patients (366 eyes with visual field defect induced by pituitary macroadenomas. All of them were treated with trans-sphenoidal surgery. Ophthalmologic evaluation, best-corrected visual acuity (BCVA, and visual field examination were performed before and 3mo after surgery. BCVA, visual field defect index mean deviation (MD, duration of symptoms, age, sex, and volume of tumors were compared. Expression of vascular endothelial growth factor (VEGF and Ki-67 of tumor tissue were detected by immunohistochemical technique. The mean age of patients was 44.23±1.29y. Ninety-three patients were female and 108 were male. The mean tumor volume was 14.36±6.23 cm3. The mean duration of preoperative symptoms was 11.50±0.88mo. Mean preoperative MD was -17.50±0.82 dB. Mean Preoperative visual acuity was 0.64±0.04. Postoperative visual field improved in 270 (73.77% eyes, unchanged in 96 (26.23% eyes. Multivariate logistic regression displayed that the factors independently influencing visual field improvement were young age (OR=1.71, 95%CI: 1.325-2.387, P=0.013, low preoperative MD absolute value (OR=1.277, 95%CI: 1.205-1.355, P After pituitary macroadenomas trans-sphenoidal resection, the independent influencing factors of the visual fields recovery were low preoperative MD absolute value, young age, small volume of tumor, and expression levels of VEGF/ Ki-67.

  7. Pontine encephalocele and abnormalities of the posterior fossa following transclival endoscopic endonasal surgery.

    Science.gov (United States)

    Koutourousiou, Maria; Filho, Francisco Vaz Guimaraes; Costacou, Tina; Fernandez-Miranda, Juan C; Wang, Eric W; Snyderman, Carl H; Rothfus, William E; Gardner, Paul A

    2014-08-01

    Transclival endoscopic endonasal surgery (EES) has recently been used for the treatment of posterior fossa tumors. The optimal method of reconstruction of large clival defects following EES has not been established. A morphometric analysis of the posterior fossa was performed in patients who underwent transclival EES to compare those with observed postoperative anatomical changes (study group) to 50 normal individuals (anatomical control group) and 41 matched transclival cases with preserved posterior fossa anatomy (case-control group) using the same parameters. Given the absence of clival bone following transclival EES, the authors used the line between the anterior commissure and the basion as an equivalent to the clival plane to evaluate the location of the pons. Four parameters were studied and compared in the two populations: the pontine location/displacement, the maximum anteroposterior (AP) diameter of the pons, the maximum AP diameter of the fourth ventricle, and the cervicomedullary angle (CMA). All measurements were performed on midsagittal 3-month postoperative MR images in the study group. Among 103 posterior fossa tumors treated with transclival EES, 14 cases (13.6%) with postoperative posterior fossa anatomy changes were identified. The most significant change was anterior displacement of the pons (transclival pontine encephalocele) compared with the normal location in the anatomical control group (p 50% of the clivus) and dura. Nine (64.3%) of the 14 patients were overweight (body mass index [BMI] > 25 kg/m(2)). An association between BMI and the degree of pontine encephalocele was observed, but did not reach statistical significance. The use of a fat graft as part of the reconstruction technique following transclival EES with dural opening was the single significant factor that prevented pontine displacement (p = 0.02), associated with 91% lower odds of pontine encephalocele (OR = 0.09, 95% CI 0.01-0.77). The effect of fat graft reconstruction was

  8. Outcomes of Primary Transsphenoidal Surgery in Cushing Disease: Experience of a Tertiary Center.

    Science.gov (United States)

    Keskin, Fatma Ela; Ozkaya, Hande Mefkure; Bolayirli, Murat; Erden, Secil; Kadioglu, Pınar; Tanriover, Necmettin; Gazioglu, Nurperi

    2017-10-01

    To report the initial and long-term remission rates and related factors, secondary treatments, and outcomes of a series of patients with Cushing disease (CD). We included 147 consecutive adult patients with CD who underwent primary transsphenoidal surgery (TSS) between 1998 and 2014 in this study. Eighty-two were followed up in the Cerrahpasa Medical Faculty Endocrinology and Metabolism outpatient clinic. Patients were requested to attend a long-term remission assessment; 55 could be contacted, and data for the remaining 27 patients' last visit to the outpatient clinics were reviewed for early and late remission. Six patients were excluded from the study. Magnetic resonance imaging (MRI) findings and pathologic results including mitosis, Ki-67 levels, and P53 in immunostaining of all patients were evaluated. Data of 82 patients with CD with an average age of 36 years [interquartile range: 29-47] were analyzed with a mean follow-up of 7.5 years [interquartile range: 5-10]. Overall initial remission rates were 72.3% after TSS. Among the 82 patients, 16 patients had Gamma Knife radiosurgery and 7 patients underwent adrenalectomy. After these additional treatments, the long-term remission rate was found as 69.7%. The highest remission rates were with microadenomas. Recurrence was most frequently seen in patients without tumor evidence on MRI. Patients with high Ki-67 levels had higher recurrence rates in long-term follow-up (P = 0.02). Life-long follow-up for patients with CD seems essential. Undetectable tumors on MRI before TSS and high Ki-67 immunopositivity were found as risk factors for tumor recurrence. Copyright © 2017 Elsevier Inc. All rights reserved.

  9. [Clinical observation on controlling antihypertension with the general anesthesia of TEAS and anesthetics in endoscopic endonasal surgery].

    Science.gov (United States)

    Zhao, Wensheng; Zhao Xian; Li, Jinjin; Fang, Jianqiao

    2015-12-01

    To study whether the dose of controlling antihypertensive drug is reduced by transcutaneous electrical acupoint stimulation (TEAS) and the anesthetics, as well as the control of blood pressure (BP) and heart rate (HR) in endoscopic endonasal surgery with general anesthesia. Sixty patients for selective endoscopic endonasal surgery with general anesthetics and controlling antihypertension involved were selected and randomized into a TEAS group, a sham-TEAS group, 30 cases in each one. The electric pads were attached to bilateral Hegu (LI 4), Zusanli (ST 36), Sanyinjiao (SP 6) and Quchi (LI 11), stimulated with Hans-200 apparatus, 3 to 5 mA, 2 Hz/100 Hz in the TEAS group based on the patients' response to comfort. No electric stimulation was applied to the sham-TEAS group. The general anesthesia started after 30 min intervention and lasted till the end of surgery. The BP and HR were observed and recorded at the end of monitoring in operation room, 10 min after tranquilization (T0), 30 min after intervention (Tj, after induction~of general anestiesa (T2), 30 min after surgery start (T3), 60 min after surgery start (T4) and 30 min after extubation (T5). The doses of vecuronium bromide, propofol and nitroglycerin were recorded statistically in surgery, as well as the operative bleeding volume, the operative time, the resuscitation time and the visual analogue scale (VAS) score after resuscitation. Compared with that at T0, the mean arterial pressure (MAP) at T2, T3, T4 and T5 in the TEAS group and at T3 and T4 in the sham-TEAS group was all reduced, indicating the significant difference (all P HR was not different significantly at the rest time points (all P > 0.05). HR was different at T2 to Ts in the sham-TEAS group statistically (all P 0.05). The general anesthesia with TEAS and anesthetics involved for controlling antihypertension contributes to the control of BP and HR in the patients in endoscopic endonasal surgery. The impacts are not obvious on the doses of

  10. Pituitary magnetic resonance imaging is not required in the postoperative follow-up of acromegalic patients with long-term biochemical cure after transsphenoidal surgery

    NARCIS (Netherlands)

    Zirkzee, E. J. M.; Corssmit, E. P. M.; Biermasz, N. R.; Brouwer, P. A.; Wiggers-de Bruine, F. T.; Kroft, L. J. M.; van Buchem, M. A.; Roelfsema, F.; Pereira, A. M.; Smit, J. W. A.; Romijn, J. A.

    2004-01-01

    After successful transsphenoidal surgery for acromegaly, life-long follow-up is required, because 10-15% of patients develop recurrence of disease. We assessed whether it is safe to perform postoperative follow-up with only biochemical evaluation in acromegalic patients initially cured by

  11. The Influence of Pituitary Size on Outcome After Transsphenoidal Hypophysectomy in a Large Cohort of Dogs with Pituitary-Dependent Hypercortisolism

    NARCIS (Netherlands)

    van Rijn, Sarah|info:eu-repo/dai/nl/392860163; Galac, S.|info:eu-repo/dai/nl/304830860; Tryfonidou, M. A.|info:eu-repo/dai/nl/24306599X; Hesselink, J. W.|info:eu-repo/dai/nl/11509573X; Penning, L. C.|info:eu-repo/dai/nl/110369181; Kooistra, H. S.|info:eu-repo/dai/nl/205285864; Meij, B. P.|info:eu-repo/dai/nl/164045805

    2016-01-01

    BACKGROUND Transsphenoidal hypophysectomy is one of the treatment strategies in the comprehensive management of dogs with pituitary-dependent hypercortisolism (PDH). OBJECTIVES To describe the influence of pituitary size at time of pituitary gland surgery on long-term outcome. ANIMALS

  12. A Case of Pseudoaneurysm of the Internal Carotid Artery Following Endoscopic Endonasal Pituitary Surgery: Endovascular Treatment with Flow-Diverting Stent Implantation

    Directory of Open Access Journals (Sweden)

    Ali Karadag

    2017-10-01

    Full Text Available Internal carotid artery (ICA pseudoaneurysm is a rare complication of endoscopic endonasal surgery occurring in 0.4–1.1% of cases. Pseudoaneurysms can subsequently result in other complications, such as subarachnoid hemorrhage, epistaxis, and caroticocavernous fistula with resultant death or permanent neurologic deficit. In this case, we illustrate endovascular treatment with a flow-diverting stent for an ICA pseudoaneurysm after endoscopic endonasal surgery for a pituitary adenoma in a 56-year-old male. Surgery was complicated by excessive intraoperative bleeding and emergent CT angiography confirmed an iatrogenic pseudoaneurysm on the anteromedial surface of the ICA. The pseudoaneurysm was treated endovascularly with flow-diverting stent implantation only. Follow-up CT angiography after three months demonstrated occlusion of the pseudoaneurysm.

  13. [USE OF ARTIFICIAL BONE OF TRICALCIUM PHOPHATE IN SELLAR FLOOR RECONSTRUCTION AFTER TRANSSPHENOIDAL MICROSURGERY FOR PITUITARY ADEOMA].

    Science.gov (United States)

    Cui, Peng; Wei, Hui; Lian, Zhigang; Dong, Bin; Zhao, Yongshun

    2015-11-01

    To explore the effectiveness of the usage of artificial bone of tricalcium phophate in sellar floor reconstruction after transsphenoidal microsurgery for pituitary adeoma. Between January and December 2014, 85 patients with pituitary adema underwent transsphenoidal microsurgery, and the clinical data were retrospectively analyzed. "Sandiwich" was used for sellar floor reconstruction in 46 cases (control group), and "sandiwich" combined with the artificial bone of tricalcium phophate in 39 cases (trial group). There was no significant difference in gender, age, disease duration, size of tumor, invasiveness, and the degree of damage to the sellar floor between 2 groups (P > 0.05). Total removal and subtotal removal of tumors were achieved in 39 cases and 7 cases of the control group, and in 33 cases and 6 cases of the trial group, showing no significant difference between 2 groups (Z = -1.303, P = 0.193). Cerebrospinal leakage occurred in 8 cases of the control group and in 10 cases of the trial group during operation, showing no significant difference (Z = -1.748, P = 0.080). The case number of cerebrospinal leakage in the control group (4 cases) was significantly more than that in the trial group (0) after operation (P = 0.020). The time of gauze removal in the trial group (3 days) was significant shorter than that in the control group [(4.3 ± 1.6) days] (t = 2.236, P = 0.033). The patients were followed up 3-14 months in the control group and 5-13 months in the trial group. No cerebrospinal leakage occurred during follow-up. Sellar floor reconstruction with artificial bone of tricalcium phophate is safe, and it can reduce cerebrospinal leakage and shorten the time of gauze removal.

  14. Current trends in surgical approach and outcomes following pituitary tumor resection.

    Science.gov (United States)

    Villwock, Jennifer A; Villwock, Mark R; Goyal, Parul; Deshaies, Eric M

    2015-06-01

    The goals of pituitary tumor resection include normalizing endocrine function, relieving mass effect, and minimizing risk of recurrence. This study investigated current trends in costs and complications for transfrontal and transsphenoidal pituitary surgery. Retrospective review of the 2008-2011 Nationwide Inpatient Sample for patients undergoing pituitary lesion resection. Demographics and outcomes were compared between transfrontal and transsphenoidal surgical approaches using χ(2) tests. Multivariate analysis was performed to investigate outcomes while controlling for confounders. There were 8,543 admissions for resection of pituitary lesions that met our inclusion criteria. Most (>90%) were treated transsphenoidally. The transfrontal approach was most frequent in the young (<35 years) and in the South. Rates of mortality and complications were higher in patients undergoing transfrontal surgery. Multivariate analysis found transsphenoidal resection was associated with a reduction in hospital costs and length of stay by over 50%; low-volume hospitals had increased cost and length of stay. There was an increased rate of transfrontal approaches at low-volume centers. Multiple factors influence outcomes of pituitary tumor resection. Transsphenoidal pituitary surgery is associated with a shorter length of stay, lower cost, and lower complication rates when compared to transfrontal surgery. Case specifics, including tumor location and size, influence approach and lead to a selection bias that cannot be controlled for in the present study. The prevalence of transfrontal resections at low-volume centers may indicate an area of further investigation. Additionally, when controlling for surgical approach, low-volume centers were found to adversely affect economic outcomes and also warrants investigation. 2c. © 2015 The American Laryngological, Rhinological and Otological Society, Inc.

  15. Simultaneous occurrence of subarachnoid hemorrhage and epistaxis due to ruptured petrous internal carotid artery aneurysm. Association with transsphenoidal surgery and radiation therapy. Case report

    International Nuclear Information System (INIS)

    Endo, Hidenori; Fujimura, Miki; Inoue, Takashi; Matsumoto, Yasushi; Ogawa, Yoshikazu; Kawagishi, Jun; Jokura, Hidefumi; Shimizu, Hiroaki; Tominaga, Teiji

    2011-01-01

    A 62-year-old woman presented with simultaneous subarachnoid hemorrhage (SAH) and massive epistaxis. The patient had been treated for pituitary prolactinoma by two transsphenoidal surgeries, gamma knife radiosurgery, and conventional radiation therapy since age 43 years. Cerebral angiography showed left petrous internal carotid artery (ICA) aneurysm with slight stenosis on the adjacent left petrous ICA. She underwent superficial temporal artery-middle cerebral artery (STA-MCA) double anastomosis with endovascular internal trapping without complication the day after onset. Postoperative course was uneventful; the patient did not develop symptomatic vasospasm, recurrent epistaxis, or cerebrospinal fluid rhinorrhea. Postoperative angiography demonstrated complete disappearance of the aneurysm with patent STA-MCA anastomosis. The patient was discharged 2 months after surgery without neurological deficit. The present case is extremely rare with simultaneous onset of SAH and epistaxis caused by ruptured petrous ICA aneurysm. The transsphenoidal surgeries and radiation therapies might have been critical in the formation of the petrous ICA aneurysm. (author)

  16. Comparative Evaluation of the Ostium After External and Nonendoscopic Endonasal Dacryocystorhinostomy Using Image Processing (Matlabs and Image J) Softwares.

    Science.gov (United States)

    Ganguly, Anasua; Kaza, Hrishikesh; Kapoor, Aditya; Sheth, Jenil; Ali, Mohammad Hasnat; Tripathy, Devjyoti; Rath, Suryasnata

    The purpose of this study was to compare the characteristics of the ostium after external dacryocystorhinostomy and nonendoscopic endonasal dacryocystorhinostomy (NEN-DCR). This cross-sectional study included patients who underwent a successful external dacryocystorhinostomy or NEN-DCR and had ≥1 month follow up. Pictures of the ostium were captured with a nasal endoscope (4 mm, 30°) after inserting a lacrimal probe premarked at 2 mm. Image analyses were performed using Image J and Contour softwares. Of the 113 patients included, external dacryocystorhinostomy group had 53 patients and NEN-DCR group had 60 patients. The mean age of patients in the NEN-DCR group (38 years) was significantly (p 0.05) in mean follow up (6 vs. 4 months), maximum diameter of ostium (8 vs. 7 mm), perpendicular drawn to it (4 vs. 4 mm), area of ostium (43 vs. 36 mm), and the minimum distance between common internal punctum and edge of the ostium (1 vs. 1 mm) between the external and NEN-DCR groups. Image processing softwares offer simple and objective method to measure the ostium. While ostia are comparable in size, their relative position differs with posteriorly placed ostia in external compared with inferior in NEN-DCR.

  17. Early versus late Gamma Knife radiosurgery following transsphenoidal surgery for nonfunctioning pituitary macroadenomas: a multicenter matched-cohort study.

    Science.gov (United States)

    Pomeraniec, I Jonathan; Kano, Hideyuki; Xu, Zhiyuan; Nguyen, Brandon; Siddiqui, Zaid A; Silva, Danilo; Sharma, Mayur; Radwan, Hesham; Cohen, Jonathan A; Dallapiazza, Robert F; Iorio-Morin, Christian; Wolf, Amparo; Jane, John A; Grills, Inga S; Mathieu, David; Kondziolka, Douglas; Lee, Cheng-Chia; Wu, Chih-Chun; Cifarelli, Christopher P; Chytka, Tomas; Barnett, Gene H; Lunsford, L Dade; Sheehan, Jason P

    2017-10-27

    OBJECTIVE Gamma Knife radiosurgery (GKRS) is frequently used to treat residual or recurrent nonfunctioning pituitary macroadenomas. There is no consensus as to whether GKRS should be used early after surgery or if radiosurgery should be withheld until there is evidence of imaging-defined progression of tumor. Given the high incidence of adenoma progression after subtotal resection over time, the present study intended to evaluate the effect of timing of radiosurgery on outcome. METHODS This is a multicenter retrospective review of patients with nonfunctioning pituitary macroadenomas who underwent transsphenoidal surgery followed by GKRS from 1987 to 2015 at 9 institutions affiliated with the International Gamma Knife Research Foundation. Patients were matched by adenoma and radiosurgical parameters and stratified based on the interval between last resection and radiosurgery. Operative results, imaging data, and clinical outcomes were compared across groups following early (≤ 6 months after resection) or late (> 6 months after resection) radiosurgery. RESULTS After matching, 222 patients met the authors' study criteria (from an initial collection of 496 patients) and were grouped based on early (n = 111) or late (n = 111) GKRS following transsphenoidal surgery. There was a greater risk of tumor progression after GKRS (p = 0.013) and residual tumor (p = 0.038) in the late radiosurgical group over a median imaging follow-up period of 68.5 months. No significant difference in the occurrence of post-GKRS endocrinopathy was observed (p = 0.68). Thirty percent of patients without endocrinopathy in the early cohort developed new endocrinopathies during the follow-up period versus 27% in the late cohort (p = 0.84). Fourteen percent of the patients in the early group and 25% of the patients in the late group experienced the resolution of endocrine dysfunction after original presentation (p = 0.32). CONCLUSIONS In this study, early GKRS was associated with a lower risk of

  18. Cirugía transnasal transesfenoidal endoscópica en afecciones de región selar Endoscopic transsphenoidal transnasal surgery in affections of the sellar region

    Directory of Open Access Journals (Sweden)

    Justo Luis González González

    2005-08-01

    aleatorizados y controlados, en busca de información más consistente en relación con el valor real de la técnica, a estas alturas del desarrollo de la cirugía hipofisaria.For a great number of pitituary tumors surgery is the first-line treatment and the microsurgical transsphenoidal approach is the most used. At present, it is performed by microscopic and endoscopic way. Recently, the endoscopic transnasal approach has emerged as an option under development that could predominate in a near future. The aim of the present paper was to evaluate by analyzing the results if it was possible to perform in our setting the endoscopic transsphenoidal transnasal approach for the lesions of the sellar region with surgical results similar at least to those obtained with the traditional microsurgical method. A limited strictly controlled and prospective cohort research of 10 patients selected according to the inclusion criteria that underwent transnasal endoscopic surgery between August 2002 and August 2003 at the Neurosurgery service of “Hermanos Ameijeiras” Hospital, was conducted. 6 cases with hypophyseal macroadenomas were operated on (3 GH-releasing, 1 PRL-secreting and 2 non-releasing hypophyseal macroadenomas. The other 4 were diagnosed LCR fistula through the sellar floor. Total exeresis of the tumor was performed in 5 of the 6 macroadenomas, whereas subtotal exeresis was attained in the other one. Rhinorrhea disappeared in 2 patients with LCR fistula and it was maintained in the other 2. Of the complications observed in 30 % of the cases, only in one (10 %, they were beyond the transoperative. It was concluded that the results obtained by using the endoscopic transnasal method make the procedure in our setting safe enough to justify its implementation and to carry out further randomized and controlled studies searching for more consistent information in relation to the real value of the technique at this level of development of the hypophyseal surgery.

  19. Design and Validation of an Open-Source, Partial Task Trainer for Endonasal Neuro-Endoscopic Skills Development: Indian Experience.

    Science.gov (United States)

    Singh, Ramandeep; Baby, Britty; Damodaran, Natesan; Srivastav, Vinkle; Suri, Ashish; Banerjee, Subhashis; Kumar, Subodh; Kalra, Prem; Prasad, Sanjiva; Paul, Kolin; Anand, Sneh; Kumar, Sanjeev; Dhiman, Varun; Ben-Israel, David; Kapoor, Kulwant Singh

    2016-02-01

    Box trainers are ideal simulators, given they are inexpensive, accessible, and use appropriate fidelity. The development and validation of an open-source, partial task simulator that teaches the fundamental skills necessary for endonasal skull-base neuro-endoscopic surgery. We defined the Neuro-Endo-Trainer (NET) SkullBase-Task-GraspPickPlace with an activity area by analyzing the computed tomography scans of 15 adult patients with sellar suprasellar parasellar tumors. Four groups of participants (Group E, n = 4: expert neuroendoscopists; Group N, n =19: novice neurosurgeons; Group R, n = 11: neurosurgery residents with multiple iterations; and Group T, n = 27: neurosurgery residents with single iteration) performed grasp, pick, and place tasks using NET and were graded on task completion time and skills assessment scale score. Group E had lower task completion times and greater skills assessment scale scores than both Group N and R (P ≤ 0.03, 0.001). The performance of Groups N and R was found to be equivalent; in self-assessing neuro-endoscopic skill, the participants in these groups were found to have equally low pretraining scores (4/10) with significant improvement shown after NET simulation (6, 7 respectively). Angled scopes resulted in decreased scores with tilted plates compared with straight plates (30° P ≤ 0.04, 45° P ≤ 0.001). With tilted plates, decreased scores were observed when we compared the 0° with 45° endoscope (right, P ≤ 0.008; left, P ≤ 0.002). The NET, a face and construct valid open-source partial task neuroendoscopic trainer, was designed. Presimulation novice neurosurgeons and neurosurgical residents were described as having insufficient skills and preparation to practice neuro-endoscopy. Plate tilt and endoscope angle were shown to be important factors in participant performance. The NET was found to be a useful partial-task trainer for skill building in neuro-endoscopy. Copyright © 2016 Elsevier Inc. All rights reserved.

  20. The recovery of the hypothalamo-pituitary-adrenal axis after transsphenoidal operation in three patients with Cushing's disease

    International Nuclear Information System (INIS)

    Lamberts, S.W.J.; Klijn, J.G.M.; Jong, F.H. de; Birkenhager, J.C.

    1981-01-01

    The recovery of the hypothalamo-pituitary-adrenal axis after selective transsphenoidal adenomectomy was studied in 3 patients with Cushing's disease by measuring basal plasma ACTH and cortisol concentrations, cortisol secretion rate, the diurnal rhythm of cortisol, and the reaction of cortisol to lysine vasopressin (LVP), of compound S to metyrapone and of cortisol and growth hormone to an insulin-induced hypoglycaemia. The third patient had been treated previously by external pituitary irradiation. In 2 patients basal plasma ACTH levels returned within normal values before plasma cortisol, but no supra-physiological plasma concentrations of ACTH were seen as has been observed after withdrawal of exogenous glucocorticoids. With regard to the different stimulation tests: at first the normal reaction of plasma cortisol to LVP returned after 3 months, at the same time as the restoration of growth hormone secretion in response to hypoglycaemia. A normalization of the reaction to metyrapone was seen thereafter while finally the reaction of cortisol to an insulin-induced hypoglycaemia and the diurnal rhythm of plasma cortisol returned 15 to 18 months after operation in the first patient and after 12 months in the second patient. Selective adenomectomy had also been carried out in the third patient, as evidenced by normal TSH, LH and FSH secretion. Hypocortisolism, and a deficient ACTH and growth hormone secretion in response to the stimuli mentioned, however, did not normalize up till 22 months after operation. The restoration of the hypothalamo-pituitary-adrenal axis after selective pituitary adenomectomy in Cushing's disease was prevented in this patient by prior external pituitary irradiation. (author)

  1. Primary Endoscopic Transnasal Transsphenoidal Surgery for Magnetic Resonance Image-Positive Cushing Disease: Outcomes of a Series over 14 Years.

    Science.gov (United States)

    Kuo, Chao-Hung; Yen, Yu-Shu; Wu, Jau-Ching; Chen, Yu-Chun; Huang, Wen-Cheng; Cheng, Henrich

    2015-09-01

    There are scant data of endoscopic transsphenoidal surgery (ETS) with adjuvant therapies of Cushing disease (CD). To report the remission rate, secondary management, and outcomes of a series of CD patients. Patients with CD with magnetic resonance imaging (MRI)-positive adenoma who underwent ETS as the first and primary treatment were included. The diagnostic criteria were a combination of 24-hour urine-free cortisol, elevated serum cortisol levels, or other tests (e.g., inferior petrosal sinus sampling). All clinical and laboratory evaluations and radiological examinations were reviewed. Forty consecutive CD patients, with an average age of 41.0 years, were analyzed with a mean follow-up of 40.2 ± 29.6 months. These included 22 patients with microadenoma and 18 with macroadenoma, including 9 cavernous invasions. The overall remission rate of CD after ETS was 72.5% throughout the entire follow-up. Patients with microadenoma or noninvasive macroadenoma had a higher remission rate than those who had macroadenoma with cavernous sinus invasion (81.8% or 77.8% vs. 44.4%, P = 0.02). After ETS, the patients who had adrenocorticotropic hormone-positive adenoma had a higher remission rate than those who had not (76.5% vs. 50%, P = 0.03). In the 11 patients who had persistent/recurrent CD after the first ETS, 1 underwent secondary ETS, 8 received gamma-knife radiosurgery (GKRS), and 2 underwent both. At the study end point, two (5%) of these CD patients had persistent CD and were under the medication of ketoconazole. For MRI-positive CD patients, primary (i.e., the first) ETS yielded an overall remission rate of 72.5%. Adjuvant therapies, including secondary ETS, GKRS, or both, yielded an ultimate remission rate of 95%. Copyright © 2015 Elsevier Inc. All rights reserved.

  2. Reasons and results of endoscopic surgery for prolactinomas: 142 surgical cases.

    Science.gov (United States)

    Akin, Safak; Isikay, Ilkay; Soylemezoglu, Figen; Yucel, Taskin; Gurlek, Alper; Berker, Mustafa

    2016-05-01

    We report herein a retrospective analysis of the results of 142 consecutive prolactinoma cases operated upon using an endoscopic endonasal trans-sphenoidal approach over a period of 6 years. Medical records of 142 cases were analysed with respect to indications for surgery, duration of hospital stay, early remission rates, failures and recurrence rates during a median follow-up of 36 months. On the basis of magnetic resonance imaging (MRI) data, 19 patients (13.4 %) had microadenoma, 113 (79.6 %) had macroadenoma, and the remaining 10 (7.0 %) had giant adenomas. Cavernous sinus invasion was identified in 25 patients by MRI and confirmed during surgery. Atypical adenoma was diagnosed in 16 patients. Sparsely granulated prolactin adenoma was identified in 99 patients (69.7 %). Our results demonstrate that male sex and higher preoperative prolactin levels are independent factors predicting persistent disease. The post-surgical complications are as follows: 2.8 % patients had meningitis, 2.1 % patients had postoperative cerebrospinal fluid leak and 2.1 % patients had panhypopituitarism. At the end of follow-up, 74.6 % patients went into remission. During follow-up period, five patients who had initial remission developed recurrence. Our series together with literature data suggest that an endoscopic endonasal trans-sphenoidal approach in the treatment of proloctinomas has a favourable rate of remission. According to the findings of this study, endoscopic endonasal trans-sphenoidal surgery might be an appropriate therapy choice for patients with prolactinoma who could not have been managed with recommended therapeutic modalities.

  3. Craniofacial fibrous dysplasia surgery: a functional approach.

    Science.gov (United States)

    Béquignon, E; Cardinne, C; Lachiver, X; Wagner, I; Chabolle, F; Baujat, B

    2013-09-01

    Craniofacial fibrous dysplasia has not only esthetic but functional impact. Surgery is controversial, ranging from conservative to radical. It involves elevated hemorrhage risk, and should be progressive, based on an individual risk/benefit analysis with the aim of improving quality of life. Three patients (one male, two female; mean age, 35 years) with evolutive orbital-temporal maxillary dysplasia were treated between 2008 and 2009 in our department. All showed exophthalmia and nasal obstruction. In one patient, symptomatology was aggravated by a frontal sinus cyst within the dysplasia. Another had associated auditory canal obstruction inducing recurrent external otitis. Optic nerve decompression was achieved on a combined coronal and endonasal approach, assisted by neuronavigation. Complementary remodelling resection, dacryocystorhinostomy and internal optic nerve decompression were performed. Functional results showed 70 % improvement on a subjective scale for eye tension and nasal obstruction. Surgery was feasible in all patients, with no complications. Current surgical management allies esthetic and functional concerns. Remodeling resection is the reference technique. The coronal approach is a good primary option for optic nerve decompression. Endonasal surgery with neuronavigation improves nasal ventilation and lacrimal canal permeability. Copyright © 2012 Elsevier Masson SAS. All rights reserved.

  4. The Pathophysiology of Early Hypotension Following Epinephrine-containing Local Anesthetic Infiltration of the Nasal Mucosa in Patients Undergoing Endoscopic Transsphenoidal Hypophysectomy: A Prospective, Observational Study.

    Science.gov (United States)

    Wiles, Matthew D; Sanders, Matthew I; Sinha, Saurabh; Mirza, Showkat; Andrzejowski, John C

    2017-07-01

    In patients undergoing endoscopic transsphenoidal hypophysectomy, the nasal mucosa is often infiltrated with local anesthetic solutions that contain epinephrine to aid hemostasis. This may, however, result in hemodynamic changes, especially hypotension. We characterized the cardiovascular changes using a LiDCOrapid monitor in 13 patients after the infiltration of 4% articaine containing 1:200,000 epinephrine. Nine (69%) had a >20% decrease in mean arterial pressure at a median time of 116 seconds after the infiltration of articaine with epinephrine. Analysis of the cardiac output data revealed that this was caused by a sustained reduction in systemic vascular resistance. The arterial blood pressure normalized over a period of 60 to 90 seconds secondary to increases in stroke volume and heart rate producing an elevation in cardiac output. Transient hypotension following the infiltration of epinephrine-containing local anesthetics may be caused by epinephrine stimulation of β2-adrenoceptors producing vasodilation.

  5. Basilar expansion of the human sphenoidal sinus: an integrated anatomical and computerized tomography study

    International Nuclear Information System (INIS)

    Haetinger, Rainer G.; Navarro, Joao A.C.; Liberti, Edson A.

    2006-01-01

    Basilar expansion of the sphenoidal sinus (BESS) was studied in order to demonstrate its critical relevance in endoscopic or microscopic endonasal surgical interventions, including access to the sphenoidal sinus itself or in transsphenoidal pituitary approaches. Direct evaluation of anatomical specimens (25 dry skulls and 25 formalin-fixed hemi heads) and the use of computerized tomography (CT) (50 dry skulls and 750 patients) showed a high BESS frequency (69%). The authors considered BESS to be critical when the posterior wall of the clivus was 2-mm thick and found a high incidence of this important anatomical variation (44%). This study also evaluated the relationship between the sinonasal septa, the clivus, and the internal carotid arteries, and a considerable regularity in the location of these structures was seen. The septa were anatomically related to the internal carotid arteries in 55% and to the clivus in 33% of the cases. In conclusion, the high frequency of critical BESS here described is relevant to endoscopic or microscopic endonasal surgical interventions, including access to the sphenoidal sinus itself or in transsphenoidal pituitary approaches. (orig.)

  6. Objective Validation of Perfusion-Based Human Cadaveric Simulation Training Model for Management of Internal Carotid Artery Injury in Endoscopic Endonasal Sinus and Skull Base Surgery.

    Science.gov (United States)

    Shen, Jasper; Hur, Kevin; Zhang, Zhipeng; Minneti, Michael; Pham, Martin; Wrobel, Bozena; Zada, Gabriel

    2017-12-29

    The emergence of minimally invasive endoscopic endonasal skull base surgery has necessitated reproducible and realistic simulators of rare vascular injuries. To assess the face and content validity of an innovative perfusion-based cadaveric model developed to simulate internal carotid artery (ICA) injury during endoscopic surgery. Otolaryngology and neurosurgery trainees attempted 3 consecutive trials of endoscopic control of a parasellar ICA injury, with standardized technical feedback. Time to hemostasis (TTH) and blood loss were trended. All participants completed validated questionnaires using a 5-point Likert scale to assess the domains of confidence gain, face validity, content validity, and curriculum applicability. Among all participants (n = 35), TTH and mean blood loss significantly decreased between first vs second attempt (P = .005), and first vs third attempt (P = .03). Following the first attempt, trainees experienced an average 63% reduction in blood loss and 59% reduction in TTH. In the quartile of most improved participants, average blood loss reduction was 1115 mL (84% reduction) and TTH of 259 s (84% reduction). There were no significant differences between trainees of varying postgraduate year or specialty. Average pre and postprocedural confidence scores were 1.38 and 3.16, respectively (P < .0001). All trainees reported model realism, which achieved mean face validity 4.82 ± 0.41 and content validity 4.88 ± 0.33. The perfusion-based human cadaveric ICA injury model achieves high ratings of face and content validity across all levels of surgical trainees, and enables safe, realistic simulation for standardized skull base simulation and future curriculum development. Objective improvements in performance metrics may translate to improved patient outcomes.

  7. Serum levels of 20 kilodalton human growth hormone (20K-hGH) in patients with acromegaly before and after treatment with octreotide and transsphenoidal surgery.

    Science.gov (United States)

    Murakami, Yoshio; Shimizu, Tadashi; Yamamoto, Masahiro; Kato, Yuzuru

    2004-06-01

    Circulating human GH (hGH) consists of several molecular isoforms. It was previously reported that the proportion of 20 kilodalton hGH (20K-hGH) was elevated in the serum of patients with active acromegaly. In this study, we investigated the effects of octreotide and transsphenoidal adenomectomy on the proportion of 20K-hGH in the serum of 7 acromegalic patients. To achieve an acute effect, octreotide (100 microg) was subcutaneously injected as a bolus. To observe the chronic effects of octreotide therapy and surgery, serum samples were obtained by repetitive blood sampling before and 3 to 8 weeks after treatment. Serum levels of 20K-hGH and 22 kilodalton hGH (22K-hGH) were determined by specific enzyme-linked immunosorbent assay. A bolus injection of octreotide elicited a parallel decrease in serum 22K-hGH and 20K-hGH, resulting in an unchanged proportion of 20K-hGH to total circulating hGH. The proportion of 20K-hGH was decreased in 4 of 4 patients 4 to 7 weeks after surgery and in 2 of 4 patients after chronic treatment with octreotide for 3 to 8 weeks. The proportion of serum 20K-hGH was positively related to mean serum 20K-hGH as well as serum total hGH levels, but not with serum IGF-I levels. These findings suggest that high serum levels of 20K-hGH or total hGH per se might elicit a chronic change in the clearance kinetics of 20K-hGH and increase the proportion of 20K-hGH in acromegalic patients.

  8. Evaluation of early visual recovery in pituitary macroadenomas after endoscopic endonasal transphenoidal surgery: Quantitative assessment with diffusion tensor imaging (DTI).

    Science.gov (United States)

    Anik, Ihsan; Anik, Yonca; Koc, Kenan; Ceylan, Savas; Genc, Hamza; Altintas, Ozgul; Ozdamar, Dilek; Baykal Ceylan, Duygu

    2011-04-01

    Visual field analyses reflect the degree of the compression to the optic nerve that results the structural damage of the nerve. These structural damages can be evaluated by diffusion tensor imaging (DTI), which assesses the structural integrity of white matter tracts. Thus, we evaluated the quantitative assessment of early visual recovery in patients with pituitary macroadenomas, corresponding DTI with visual field analyses. Seventy-two patients who had pituitary macroadenomas with visual field defects were included in the study retrospectively. All patients were operated on by pure endoscopic transphenoidal approach. Visual field assessment using Humphrey field analyzer and DTI with 3T magnet were performed in the preoperative and postoperative second day and sixth month. Mean symptom duration was 14.7 ± 10.5 weeks in the full recovery group patients, 50.1 ± 29.1 weeks in partial recovery patients, and 92.4 ± 15.4 weeks in the ones with no recovery. There was a significant difference at p < 0.001 among the groups. On visual field analysis, the visual lost was mostly recognized at upper temporal levels preoperatively. Visual field findings of both eyes were improved in 80% of the patients. Among these, 25% revealed full recovery, 55.6% partial recovery, and 19.4% did not demonstrate significant changes. DTI assessments of affected sides revealed preoperative fractional anisotropy (FA) values below 0.400 and mean diffusivity (MD) values over 1,400 × 10(-6) mm(2) s(-1) were related with no visual improvement in the postoperative 6 months period. The percentage increase of mean FA values of the affected areas postoperatively were found to be 21.9% in totally responded patients, 20.6% in partial responded patients, and 9.8% in patients that did not respond. There is a correlation between DTI-derived FA values of the optic nerves and visual parameters. DTI assessments of the affected sides with FA and MD values may help to estimate the response

  9. Prediction of postoperative diabetes insipidus using morphological hyperintensity patterns in the pituitary stalk on magnetic resonance imaging after transsphenoidal surgery for sellar tumors.

    Science.gov (United States)

    Hayashi, Yasuhiko; Kita, Daisuke; Watanabe, Takuya; Fukui, Issei; Sasagawa, Yasuo; Oishi, Masahiro; Tachibana, Osamu; Ueda, Fumiaki; Nakada, Mitsutoshi

    2016-12-01

    Diabetes insipidus (DI) remains a complication of transsphenoidal surgery (TSS) for sellar and parasellar tumors. Antidiuretic hormone (ADH) appears as hyper intensity (HI) in the pituitary stalk and the posterior lobe of the pituitary gland on T1-weighted magnetic resonance (MR) imaging. Its disappearance from the posterior lobe occurs with DI, indicating a lack of ADH. The appearance of HI in the pituitary stalk indicates disturbances in ADH transport. This retrospective study included 172 patients undergoing TSS for sellar tumors at our institute from 2006 to 2014. Sequential T1-weighted MR images without enhancement were evaluated for HI in the pituitary stalk and the posterior lobe to assess the localization of ADH before and at intervals after TSS. DI was assessed pre- and postoperatively. HI in the pituitary stalk showed the following morphology: (1) ovoid in the distal end of the pituitary stalk (group A), (2) linear in the distal part of the pituitary stalk (group B), (3) linear in the whole pituitary stalk (group C). Preoperative DI occurred in 6 patients (3.5 %) with no HI observed in the posterior lobe. Postoperative DI was transient in 82 patients (47.7 %), and permanent in 11 (6.4 %). One week after surgery, HI was absent in the posterior lobe in 74 patients (43.0 %), and present in the pituitary stalk in 99 patients (57.6 %); both were significantly correlated with postoperative DI (p < 0.001). The absence of HI in the posterior lobe (A, 48.9 %; B, 68.3 %; C, 92.3 %), persistence of DI (A, 3.7 days; B, 45.9 days; C, 20.5 months), and duration until HI recovery in the posterior lobe (A, 3.6 months; B, 6.8 months; C, 22.9 months) were greatest in group C, followed by group B, and then group A. Fourteen group A patients did not have postoperative DI despite having HI in the pituitary stalk and the posterior lobe. Four group C patients developed permanent DI with persistence HI in the pituitary stalk. HI in the pituitary stalk and its

  10. Long-term outcomes of tissue-based ACTH-antibody assay-guided transsphenoidal resection of pituitary adenomas in Cushing disease.

    Science.gov (United States)

    Erfe, J Mark; Perry, Avital; McClaskey, John; Inzucchi, Silvio E; James, Whitney Sheen; Eid, Tore; Bronen, Richard A; Mahajan, Amit; Huttner, Anita; Santos, Florecita; Spencer, Dennis

    2017-10-13

    OBJECTIVE Cushing disease is caused by a pituitary micro- or macroadenoma that hypersecretes adrenocorticotropic hormone (ACTH), resulting in hypercortisolemia. For decades, transsphenoidal resection (TSR) has been an efficacious treatment but with certain limitations, namely precise tumor localization and complete excision. The authors evaluated the novel use of a double-antibody sandwich assay for the real-time quantitation of ACTH in resected pituitary specimens with the goals of augmenting pathological diagnosis and ultimately improving long-term patient outcome. METHODS This study involved a retrospective review of records and an analysis of assay values, pathology slides, and MRI studies of patients with Cushing disease who had undergone TSR in the period from 2009 to 2014 and had at least 1 year of follow-up in coordination with an endocrinologist. In the operating room, biopsy specimens from the patients had been analyzed for tissue ACTH concentration. Additional samples were simultaneously sent for frozen-section pathological analysis. The ACTH assay performance was compared against pathology assessments of surgical tumor samples using receiver operating characteristic (ROC) analysis and against pre- and postoperative MRI studies. RESULTS Fourteen patients underwent TSR with guidance by ACTH-antibody assay and pathological assessment of 127 biopsy samples and were followed up for an average of 3 years. The ACTH threshold for discriminating adenomatous from normal tissue was 290,000 pg/mg of tissue, based on jointly maximized sensitivity (95.0%) and specificity (71.3%). Lateralization discordance between preoperative MRI studies and surgical visualization was noted in 3 patients, confirming the impression that MRI alone may not achieve optimal localization. A majority of the patients (85.7%) attained long-term disease remission based on urinary free cortisol levels, plasma cortisol levels, and long-term corticosteroid therapy. Comparisons of patient

  11. Virtual reality surgical anatomy of the sphenoid sinus and adjacent structures by the transnasal approach.

    Science.gov (United States)

    Wang, Shou-Sen; Xue, Liang; Jing, Jun-Jie; Wang, Ru-Mi

    2012-09-01

    To examine the three-dimensional virtual anatomical features of the sphenoid sinus and adjacent structures during virtual surgery and explore their relevance to actual transsphenoidal surgery. CT images of the sphenoid sinus and surrounding structures from 28 Chinese adult patients were measured using a 16-slice helical CT scanner. Image analysis was performed using the volume-rendering method. Two experienced neurosurgeons wearing stereoscopic glasses performed virtual transsphenoidal surgery by the transnasal approach. The virtual anatomical features of the sphenoid sinus and the adjacent structures during virtual surgery were described. The distance from the sphenopalatine foramen to the left and right sphenoid ostium was 10.1 ± 2.7 mm and 10.5 ± 3.2 mm, respectively, to the left and right sphenoidal crest 12.9 ± 2.0 mm and 12.8 ± 2.2 mm, respectively, and to the left and right uncinate process 24.0 ± 1.9 mm and 23.9 ± 2.0 mm, respectively. The distance from the uncinate process to the medial and lateral edge of the most prominent part of the anterior bend of the cavernous internal carotid artery (ICA) was 33.7 ± 3.7 mm and 34.8 ± 3.7 mm, respectively, and the angle between the two lines was 9.7 ± 1.9°. The study provides virtual anatomical information about the sphenoid sinus and important surrounding structures that is essential for successful real life transsphenoidal surgery. Copyright © 2011 European Association for Cranio-Maxillo-Facial Surgery. Published by Elsevier Ltd. All rights reserved.

  12. Cerebrospinal fluid fistula after endoscopic transsphenoidal surgery: experience in a spanish center Fístula liquórica após cirurgia transesfenoidal endoscópica: experiência de um centro espanhol

    Directory of Open Access Journals (Sweden)

    Alicia Del Carmen Becerra Romero

    2010-06-01

    Full Text Available BACKGROUND: Postoperative cerebrospinal fluid (CSF fistula is the most serious complication after transsphenoidal surgery. OBJECTIVE: To analyze the incidence of CSF fistula after endoscopic transsphenoidal surgery for tumor removal in sellar region; to discuss associated factors and methods used for sellar closure. METHOD: Retrospective study of 67 patients (73 surgeries operated via transsphenoidal endoscopy at Hospital Vall D'Hebron and Hospital Clinic of the Universidad de Barcelona, Spain. The data collected included: age, sex, hospitalization stay, suprasellar extension of the lesion, type of tumor, evidence of intraoperative CSF fistula, complications of postoperative CSF fistula, previous surgery and radiotherapy. RESULTS: Six patients (8.2% had postoperative CSF fistula, and their average hospitalization was 5 days longer with resulting complications: two of whom had pneumoencephalus and two with meningitis. No association was found between the data collected and postoperative CSF fistula. CONCLUSION: The rate of CSF fistula after endoscopic transsphenoidal surgery from the present study is contained within the literature. Unlike other reports, no association between the variables and postoperative CSF fistula was found in this report.A fístula liquórica pós-operatória é a complicação mais séria após cirurgia transesfenoidal. OBJETIVO: Analisar a incidência de fístula liquórica após cirurgia endoscópica transesfenoidal para remoção de tumores selares, discutir fatores associados e método utilizado para fechamento selar. MÉTODO: Estudo retrospectivo de 67 pacientes (73 cirurgias operados via endoscopia transesfenoidal no Hospital Vall D'Hebron e Hospital Clínic da Universidad de Barcelona, Espanha. Os dados coletados foram: idade, sexo, dias de internação, extensão supra-selar da lesão, tipo de tumor, evidência de fístula liquórica intra-operatória, complicações da fístula liquórica p

  13. Pituitary apoplexy in a teenager--case report.

    Science.gov (United States)

    Chao, Chen-Cheng; Lin, Chun-Ju

    2014-06-01

    Pituitary apoplexy is a rare clinical emergency which results from hemorrhage or infarction in the pituitary gland. We present a 14-year-old girl with pituitary apoplexy and review the literature. Our patient experienced blurred vision, nausea, and headache. Her best-corrected visual acuity was 20/200 and 20/20. Confrontation test visual field testing revealed bitemporal hemianopsia. Brain imaging demonstrated a suprasellar mass. The microscopic endonasal transsphenoidal approach only found 5-10 mL brownish fluid-like material. Pathology confirmed no malignancy. Pituitary apoplexy was diagnosed. Her nausea and headache gradually improved. Six months after operation, her best-corrected visual acuity had improved to 20/30 and 20/20. Although pituitary apoplexy is rare in pediatric patients, prompt evaluation including detailed ophthalmic examination, biochemical evaluation, endocrine workup, and image study are very important. Copyright © 2014 Elsevier Inc. All rights reserved.

  14. [Informed Treatment Consent and Refusal in Advanced Endonasal Surgery: The Ethical Dilemma of Olfaction Sacrifice in Surgery for Chronic Rhinosinusitis with Polyposis].

    Science.gov (United States)

    Subtil, João; Araújo, João Pedro; Saraiva, José; Santos, Alberto; Vera-Cruz, Paulo; Paço, João; Pais, Diogo

    2015-01-01

    Olfaction is frequently affected in chronic rhino-sinusitis with polyposis and has been recognised to have important impact on quality of life. Surgical resolution on cases of maximal medical therapy failure is an option to relieve symptoms, with debates as to how extensive surgery should be. A more radical approach will achieve better disease control with less relapse, but can also compromise olfaction. This decision about a more radical surgical approach should be shared with the patient. Thorough informed consent regarding disease control and hyposmia should be taken. Literature review and consultation with a board of experts. We propose some elements to be included in the informed consent discussion, in order to broadly address the surgical limitations regarding anosmia as a frequent complaint, as well as the different options and their associated consequences. Radical surgery decision making should be shared with the patient and the informed consent should be as thorough as possible regarding disease control and hyposmia resolution.

  15. Dacriocistorrinostomia transnasal vídeo-endoscópica com Nd: YAG laser e diodo laser Endonasal dacriocystorhinosthomy with Nd: YAG laser and diodo laser

    Directory of Open Access Journals (Sweden)

    Eurípedes da Mota Moura

    2004-10-01

    Full Text Available OBJETIVO: Avaliar a técnica de dacriocistorrinostomia para o tratamento das obstruções do ducto lacrimo-nasal, pela vídeo-endoscopia transnasal com ND:YAG "laser" e Diodo "laser". MÉTODOS: Cinqüenta e uma cirurgias de dacriocistorrinostomia transnasal vídeo-endoscópica com Nd:YAG "laser" e Diodo "laser" foram realizadas em 42 pacientes, 36 do sexo feminino e 6 do masculino com idade variando de 3 a 92 anos; idade média 52,3 anos, no período de abril 1997 a fevereiro 2003. RESULTADO: O índice de sucesso na remissão dos sintomas foi de 92,15%. Em todos os pacientes era feita entubação bicanalicular com silicone e mantida por seis a oito semanas. CONCLUSÕES: A técnica empregada mostrou-se eficaz no tratamento das obstruções do ducto lacrimo-nasal. Não se observou diferença de resultados quando se utilizou Nd:YAG e Diodo "laser". O pós-operatório em todos os casos foi confortável e sem hemorragias.PURPOSE: To evaluate the technique of dacryocysthorrinosthomy for the treatment of nasolacrimal duct obstruction, by transnasal endoscopic video-assisted approach with Nd:YAG laser and diode laser. METHODS: Fifty one surgeries dacryocysthorrinostomy transnasal endoscopic video assisted were performed in 42 patients, 36 females, 6 males, aged between 3 and 92 years, mean age 52.3 years, in the period of April 1997 to February 2003. RESULT: The surgery successfully relieved lacrimal duct obstruction in 92.15% of the patients. CONCLUSION: The technique was efficient for the treatment of nasolacrimal obstruction. In all patients bicanalicular silicone stents were inserted at the time of surgery and removed after six to eight weeks. There is no difference in the results between Nd:YAG and diode laser. The postoperative period in all cases was comfortable and there was no hemorrhage.

  16. Quality of Life and Work Capacity Are Unrelated to Approach or Complications After Pituitary Surgery.

    Science.gov (United States)

    Uvelius, Erik; Castelo, Nazia; Kahlon, Babar; Svensson, Christer; Cervin, Anders; Höglund, Peter; Valdemarsson, Stig; Siesjö, Peter

    2017-12-01

    Endoscopic pituitary surgery has shown favorable clinical outcomes. Less is known about the impact of surgical approaches on health-related quality of life (HRQoL) and work capacity. The present study was undertaken to compare transsphenoidal microscope-assisted surgery with endoscopic transsphenoidal surgery regarding preoperative and surgical factors for the final outcome of HRQoL and work capacity. In a retrospective study of patients operated on for pituitary adenoma, outcome was compared between those operated on before and after transition with endoscopic surgery at our department. Data were gathered via patient questionnaires and patients' files. After exclusions, 235 patients were included (99 microsurgical and 136 endoscopic). Frequency of complications was similar but tumor size was significantly larger in the endoscopic group. Complications did not affect HRQoL or work capacity. HRQoL was not affected by surgical technique but showed an overall trend toward lower values compared with the general population. Sick leave, return to work frequency, and permanent sick leave were not affected by surgical technique. Female gender was a factor for lower ratings in all outcome variables. Surgical technique does not influence HRQoL or work capacity in this long-term follow-up although both are decreased compared with the general population. We conclude that fully endoscopic pituitary surgery, despite including larger tumors, bears the same risk for complications as microsurgery. In addition, females have a greater risk for decrease in HRQoL and work ability. This factor should be taken into account when informing patients and appreciating expectations of treatment. Copyright © 2017 Elsevier Inc. All rights reserved.

  17. Laparoscopic adrenalectomy: Gaining experience by graded approach

    Directory of Open Access Journals (Sweden)

    Dalvi Abhay

    2006-01-01

    Full Text Available INTRODUCTION: Laparoscopic adrenalectomy (LA has become a gold standard in management of most of the adrenal disorders. Though report on the first laparoscopic adrenalectomy dates back to 1992, there is no series of LA reported from India. Starting Feb 2001, a graded approach to LA was undertaken in our center. Till March 2006, a total of 34 laparoscopic adrenalectomies were performed with success. MATERIALS AND METHODS: The endocrinology department primarily evaluated all patients. Patients were divided into Group A - unilateral LA and Group B - bilateral LA (BLA. The indications in Group A were pheochromocytoma (n=7, Conn′s syndrome (n=3, Cushing′s adenoma (n=2, incidentaloma (n=2; and in Group B, Cushing′s disease (CD following failed trans-sphenoid pituitary surgery (n = 8; ectopic ACTH- producing Cushing′s syndrome (n=1 and congenital adrenal hyperplasia (CAH (n=1. The lateral transabdominal route was used. RESULTS: The age group varied from 12-54 years, with mean age of 28.21 years. Average duration of surgery in Group A was 166.43 min (40-270 min and 190 min (150- 310 min in Group B. Average blood loss was 136.93 cc (20-400 cc in Group A and 92.5 cc (40-260 cc in Group B. There was one conversion in each group. Mean duration of surgical stay was 1.8 days (1-3 days in Group A and 2.6 days (2-4 days in Group B. All the patients in both groups were cured of their illness. Three patients in Group B developed Nelson′s syndrome. The mean follow up was of 24.16 months (4-61 months. CONCLUSION: LA though technically demanding, is feasible and safe. Graded approach to LA is the key to success.

  18. Modified One-Piece Extended Transbasal Approach for Endoscopic-Assisted Microsurgical Resection of Tuberculum Sellae Meningioma: Operative Video and Technical Nuances.

    Science.gov (United States)

    Liu, James K; Watanabe, Kentaro

    2018-02-01

    The optimal approach for surgical resection of tuberculum sellae meningiomas remains controversial. Approach selection is largely based on a variety of factors, such as tumor size, extent and location relative to the optic canal and internal carotid artery, the presence of vascular encasement, and surgeon's preference. In this operative video manuscript, the authors demonstrate the importance of an open transcranial approach when the tumor extends lateral to the optic nerve over the internal carotid artery into the opticocarotid triangle, which is a difficult region to safely access with a purely endoscopic endonasal approach. We present a case of an endoscopic-assisted microsurgical resection of a tuberculum sellae meningioma using a modified one-piece extended transbasal approach in a patient with unilateral visual loss. The approach allows both interhemispheric and subfrontal routes to the suprasellar region. Early optic nerve decompression and division of the falciform ligament is critical to optimize visual outcomes. This video atlas demonstrates the operative technique and surgical nuances of the skull base approach, optic nerve decompression, tumor-arachnoid dissection, and safe handling of the neurovascular structures. A gross total resection was achieved and the patient had restoration of normal vision with normal pituitary function. In summary, the modified one-piece extended transbasal approach with endoscopic assistance is an important strategy in the armamentarium for surgical management of tuberculum sellae meningiomas. The link to the video can be found at: https://www.youtube.com/watch?v=jKNtRzMSFVE .

  19. Frontobasal Midline Meningiomas: Is It Right To Shed Doubt on the Transcranial Approaches? Updates and Review of the Literature.

    Science.gov (United States)

    Ruggeri, Andrea Gennaro; Cappelletti, Martina; Fazzolari, Benedetta; Marotta, Nicola; Delfini, Roberto

    2016-04-01

    Traditionally, the surgical removal of tuberculum sellae meningioma (TSM) and olfactory groove meningioma (OGM) requires transcranial approaches and microsurgical techniques, but in the last decade endoscopic expanded endonasal approaches have been introduced: transcribriform for OGMs and transtuberculum-transplanum for TSM. A comparative analysis of the literature concerning the two types of surgical treatment of OGMs and TSM is, however, difficult. We conducted a literature search using the PubMed database to compare data for endoscopic and microsurgical techniques in the literature. We also conducted a retrospective analysis of selected cases from our series presenting favorable characteristics for an endoscopic approach, based on the criteria of operability of these lesions as generally accepted in the literature, and we compared the results obtained in these patients with those in the endoscopic literature. We believe that making the sample more homogeneous, the difference between microsurgical technique and endoscopic technique is no longer so striking. A greater radical removal rate, a reduced incidence of cerebrospinal fluid fistula and, especially, the possibility of removing lesions of any size are advantages of transcranial surgery; a higher percentage of improvement in visual outcome and a lower risk of a worsening of a pre-existing deficit or onset of a new deficit are advantages of the endoscopic technique. At present, the microsurgical technique is still the gold standard for the removal of the anterior cranial fossa meningiomas of all sizes, and the endoscopic technique remains a second option in certain cases. Copyright © 2016 Elsevier Inc. All rights reserved.

  20. Design of a multifiber light delivery system for photoacoustic-guided surgery

    Science.gov (United States)

    Eddins, Blackberrie; Bell, Muyinatu A. Lediju

    2017-04-01

    This work explores light delivery optimization for photoacoustic-guided minimally invasive surgeries, such as the endonasal transsphenoidal approach. Monte Carlo simulations were employed to study three-dimensional light propagation in tissue, comprising one or two 4-mm diameter arteries located 3 mm below bone, an absorbing metallic drill contacting the bone surface, and a single light source placed next to the 2.4-mm diameter drill shaft with a 2.9-mm diameter spherical drill tip. The optimal fiber distance from the drill shaft was determined from the maximum normalized fluence to the underlying artery. Using this optimal fiber-to-drill shaft distance, Zemax simulations were employed to propagate Gaussian beams through one or more 600 micron-core diameter optical fibers for detection on the bone surface. When the number of equally spaced fibers surrounding the drill increased, a single merged optical profile formed with seven or more fibers, determined by thresholding the resulting light profile images at 1/e times the maximum intensity. We used these simulations to inform design requirements, build a one to seven multifiber light delivery prototype to surround a surgical drill, and demonstrate its ability to simultaneously visualize the tool tip and blood vessel targets in the absence and presence of bone. The results and methodology are generalizable to multiple interventional photoacoustic applications.

  1. Pituitary Apoplexy due to the Diagnostic Test in a Cushing"s Disease Patient.

    Science.gov (United States)

    Kuzu, Fatih; Unal, Mustafa; Gul, Sanser; Bayraktaroglu, Taner

    2018-01-01

    Pituitary apoplexy is a medical condition that needs urgent diagnosis and treatment. It may occur spontaneously or may be precipitated by a variety of reasons including dynamic endocrine tests. Although pituitary apoplexy is usually seen in nonfunctional pituitary adenoma, it can also be seen in ACTH secreting macroadenomas. ACTH secreting adenomas present usually as microadenomas and in these patients apoplexy is rarely seen. In this paper we present a 30-year-old male patient with a history of Cushing"s disease who suffered from pituitary apoplexy after the 1 mg dexamethasone suppression test. He underwent endoscopic endonasal transsphenoidal surgery and his symptoms and signs were significantly improved.

  2. Skull base tumor model.

    Science.gov (United States)

    Gragnaniello, Cristian; Nader, Remi; van Doormaal, Tristan; Kamel, Mahmoud; Voormolen, Eduard H J; Lasio, Giovanni; Aboud, Emad; Regli, Luca; Tulleken, Cornelius A F; Al-Mefty, Ossama

    2010-11-01

    Resident duty-hours restrictions have now been instituted in many countries worldwide. Shortened training times and increased public scrutiny of surgical competency have led to a move away from the traditional apprenticeship model of training. The development of educational models for brain anatomy is a fascinating innovation allowing neurosurgeons to train without the need to practice on real patients and it may be a solution to achieve competency within a shortened training period. The authors describe the use of Stratathane resin ST-504 polymer (SRSP), which is inserted at different intracranial locations to closely mimic meningiomas and other pathological entities of the skull base, in a cadaveric model, for use in neurosurgical training. Silicone-injected and pressurized cadaveric heads were used for studying the SRSP model. The SRSP presents unique intrinsic metamorphic characteristics: liquid at first, it expands and foams when injected into the desired area of the brain, forming a solid tumorlike structure. The authors injected SRSP via different passages that did not influence routes used for the surgical approach for resection of the simulated lesion. For example, SRSP injection routes included endonasal transsphenoidal or transoral approaches if lesions were to be removed through standard skull base approach, or, alternatively, SRSP was injected via a cranial approach if the removal was planned to be via the transsphenoidal or transoral route. The model was set in place in 3 countries (US, Italy, and The Netherlands), and a pool of 13 physicians from 4 different institutions (all surgeons and surgeons in training) participated in evaluating it and provided feedback. All 13 evaluating physicians had overall positive impressions of the model. The overall score on 9 components evaluated--including comparison between the tumor model and real tumor cases, perioperative requirements, general impression, and applicability--was 88% (100% being the best possible

  3. Transsphenoidal hypophysectomy in beagle dogs: evaluation of a microsurgical technique

    International Nuclear Information System (INIS)

    Meij, B.P.; Voorhout, G.; Ingh, T.S.G.A.M. van den; Hazewinkel, H.A.W.; Verlaat, J.W. van 't

    1997-01-01

    Objective-Assessment of a microsurgical technique for transsphenoidalhypophysectomy in dogs. Study Design-Prospective study using physicalexamination, pituitary function testing, computed tomography (CT), and histological examination at autopsy. Animals or Sample Population-Eight laboratory beagle dogs. Methods-Pituitary function was assessed before and at 10 weeks after hypophysectomy by combined administration of four releasing hormones (anterior pituitary), administration of haloperidol (pars intermedia), and infusion of hypertonic saline (posterior pituitary). Results-CT imaging enabled accurate preoperative localization of the pituitary. Appropriate positioning and surgical technique facilitated exposure of the pituitary and its extraction without hemorrhage. Postoperative recovery was generally uncomplicated. None of the eight dogs had somatotropic. gonadotropic, lactotropic, melanotropic, or posterior pituitary responses to stimulation at 10 weeks after hypophysectomy. Four dogs (ACTH nonresponders) also had no corticotropicresponse and four (ACTH responders) bad small but significant responses in the combined anterior pituitary function test. Adrenocortical atrophy was more pronounced in the ACTH nonresponders than in the responders. No residual pituitary tissue was found along the ventral hypothalamic diencephalon but nests of pituitary cells were found embedded infibrous tissue in the sella turcica. Conclusions-The surgical technique proved to be safe and effective. Microscopic nests of pituitary cells in the sella turcica may be responsible for residual corticotropic response to hypophysiotropic stimulation after hypophysectomy. Clinical Relevance-The surgical technique may be used in the treatment of dogs with pituitary-dependent hyperadrenocorticism. The corticotropic response is the most sensitive criterion in assessing completeness of hypophysectomy in dogs. (C) Copyright 1997 by The American College of Veterinary Surgeons

  4. Kinetic approach

    Indian Academy of Sciences (India)

    Collapse of a Bose gas: Kinetic approach ... Thermodynamical, statistical and static properties of condensates; Ultracold and trapped gases; matter waves. ... of a harmonically trapped attractively interacting Bose gas below the condensation point by introducing a kinetic approach within the Hartee-Fock approximation.

  5. Pedagogical approaches

    DEFF Research Database (Denmark)

    Lund Larsen, Lea

    questions are: How (much) and what do teachers learn from experience? And how do teachers of adults develop their pedagogical approach? I examine the field of adult learners from the teachers’ perspective. Firstly, I identify some of the commonly described characteristics of adults as learners...... in formal settings, but in most teaching settings, the teachers act alone and develop their pedagogical approaches/- teaching strategies with no synchronous sparring from a colleague. Adult learners have particular needs and characteristics that their teachers must be able to address (cf. Knowles...

  6. Capability approach

    DEFF Research Database (Denmark)

    Jensen, Niels Rosendal; Kjeldsen, Christian Christrup

    Lærebogen er den første samlede danske præsentation af den af Amartya Sen og Martha Nussbaum udviklede Capability Approach. Bogen indeholder en præsentation og diskussion af Sen og Nussbaums teoretiske platform. I bogen indgår eksempler fra såvel uddannelse/uddannelsespolitik, pædagogik og omsorg....

  7. Narrative approaches

    DEFF Research Database (Denmark)

    Stelter, Reinhard

    2012-01-01

    Narrative coaching is representative of the new wave – or third generation – of coaching practice . The theory and practice of narrative coaching takes into account the social and cultural conditions of late modern society, and must be seen as intertwined with them. Some initial conceptualizations...... of narrative coaching were developed by David Drake (2006, 2007, 2008, 2009) in the USA and Australia, by Ho Law in the UK (Law, 2007a + b; Law & Stelter, 2009) and by Reinhard Stelter (2007, 2009, 2012, in preparation; Stelter & Law, 2010) in Denmark. In the following chapter the aim is to present coaching...... as a narrative-collaborative practice, an approach that is based on phenomenology, social constructionism and narrative theory. Seeing narrative coaching as a collaborative practice also leads to reflecting on the relationship between coach and coachee(s) in a new way, where both parts contribute to the dialogue...

  8. Transnasal endoscopic surgery for the treatment of fibrous dysplasia of maxillary sinus associated to aneurysmal bone cyst in a 5-year-old child.

    Science.gov (United States)

    Pasquini, Ernesto; Ceroni Compadretti, Giacomo; Sciarretta, Vittorio; Ippolito, Antonio

    2002-01-11

    Fibrous dysplasia (FD) and aneurysmal bone cyst involving the facial skeleton are rare but their synchronous association in other parts of the body is well-known. The most common treatment for these lesions has been based on surgical resection using an external approach. Only recently has the endonasal endoscopic approach been utilized for the partial or complete removal of these lesions. In this report, we attempt to outline the effectiveness of the endonasal endoscopic approach for the treatment of a 5-year-old child affected by a fibrous dysplasia associated with an aneurysmal bone cyst of the right maxillary.

  9. A Novel Approach to Brachycephalic Syndrome. 2. Laser-Assisted Turbinectomy (LATE).

    Science.gov (United States)

    Oechtering, Gerhard U; Pohl, Sabine; Schlueter, Claudia; Schuenemann, Riccarda

    2016-02-01

    To introduce a new surgical procedure based on interventional, laser-assisted removal of obstructing turbinate tissue to improve endonasal airway patency in brachycephalic dogs and to confirm the short and long term results using computed tomography (CT) and rhinoscopy. Prospective clinical study. Brachycephalic dogs (n = 158; 70 Pugs, 77 French Bulldogs, 11 English Bulldogs) referred for treatment of severe respiratory distress because of brachycephalic syndrome. Computed tomography and anterior and posterior rhinoscopy were performed to evaluate endonasal obstruction. Laser-assisted turbinectomy (LATE) using a diode laser was performed as part of a multilevel surgery. Nasal conchae that were causing airway obstruction were removed. The obstructing parts of the conchae were safely and efficiently removed by LATE, shaping a patent nasal airway in all dogs. The newly developed surgical procedure involved 3 steps: turbinectomy of the (1) concha nasalis ventralis; (2) rostral aberrantly growing turbinates (RAT); and (3) caudal aberrantly growing turbinates (CAT). Complications of the procedure included transient intraoperative hemorrhage in 51 of 158 dogs (32.3%); however, a temporary tamponade was necessary in only 2/158 dogs (1.3%). After 6 months, regrowth of turbinates required resection of possibly re-obstructing tissue in 25/158 dogs (15.8%; 1 Pug and 24 French Bulldogs). LATE is an effective method for creating a patent nasal airway in brachycephalic dogs with intranasal obstruction. © Copyright 2016 by The American College of Veterinary Surgeons.

  10. Cirurgia endoscópica transnasal da região selar: estudo dos primeiros 100 casos Transnasal endoscopic surgery of the sellar region: study of the first 100 cases

    Directory of Open Access Journals (Sweden)

    Jackson Gondim

    2003-09-01

    custos hospitalares. As desvantagens são a diminuição da profundidade de campo, a necessidade de constante controle do endoscópio e a necessidade de maior experiência com as técnicas de endoscopia.An endoscopic endonasal transsphenoidal approach to the sella was performed in 100 consecutive patients, with a follow up from 3 to 55 months: 57 females and 43 males, age ranging from 14 and 70 years. 76 cases pituitary adenomas: 22 were acromegaly (7 microadenomas and 15 macroadenomas; 21 null cell adenomas (3 microadenomas and 18 macroadenomas; 19 Cushing disease (11 microadenomas and 8 macroadenomas, 10 prolactinomas (6 microadenomas and 4 macroadenomas, and 4 LH adenomas (4 macroadenomas. In this serie, remission was achieved in 44.8% for macroadenomas, 60% for acromegaly, 27.7% for null cell adenoma, 50% for Cushing disease, 50% for prolactinomas and 50% for LH adenomas, and 81.4% for microadenomas 85% for acromegaly, 100% for null cell adenoma, 81.8% for Cushing disease, 66% for prolactinoma. We had also four craniopharyngiomas, four sphenoidal mucocele, three sphenoidal aspergillus, one Rathke cyst, one hypophysitis, one cavernous aneurysm, one encefalocele, one intrasellar meningioma, one intrasellar tuberculoma and a sphenoid fibrous dysplasia. In this series we also had six fistulas of the anterior base that were completely cured. We had a mortality of 2, one null cell giant adenoma in a 57 years old man and another patient, 38 years old, with a giant craniopharyngioma. The morbidity was: two cured meningitis, three cured fistulas, and two permanent diabetes insipidus. Endoscopic endonasal transsphenoidal surgery in this series resulted with comparable surgical outcomes to conventional microscopic transsphenoidal surgery. The advantages of this technique have been represented by an easier access to the lesion, better visualisation and increased illumination of the surgical sites, microdissection of the tumor with maximum preservation of the pituitary function

  11. Persistent CSF Rhinorrhoea, Pneumocephalus, and Recurrent Meningitis Following Misdiagnosis of Olfactory Neuroblastoma

    Directory of Open Access Journals (Sweden)

    Neil Barua

    2010-01-01

    Full Text Available A 41-year-old female patient was admitted with streptococcal meningitis on a background of 5-month history of CSF rhinorrhoea. Imaging revealed an extensive skull base lesion involving the sphenoid and ethmoid sinuses, the pituitary fossa with suprasellar extension and bony destruction. Histological examination of an endonasal transethmoidal biopsy suggested a diagnosis of olfactory neuroblastoma. A profuse CSF leak occurred and the patient developed coliform meningitis. A second endonasal endoscopic biopsy was undertaken which demonstrated the tumour to be a prolactinoma. Following endonasal repair of the CSF leak and lumbar drainage, she developed profound pneumocephalus. The patient underwent three further unsuccessful CSF leak repairs. Definitive control of the CSF leak was finally achieved through a transcranial approach with prolonged lumbar drainage. This case illustrates some of the potentially devastating complications which can occur as a consequence of complex skull base lesions. A multidisciplinary approach may be required to successfully manage such cases.

  12. National long-lasting effect of endonasal endoscopic sphenopalatine artery clipping for epistaxis

    DEFF Research Database (Denmark)

    Ludvigsen Gede, Lisbeth; Aanaes, Kasper; Collatz, Helle

    2013-01-01

    We consider sphenopalatine artery ligation to be a safe and effective treatment of posterior epistaxis as the long-term need for revision surgery and the complication rates are low. Surgery should be considered earlier in the treatment of posterior epistaxis....

  13. EVALUATING THE EFFICACY OF PRESERVING THE MUCOSAL FLAP IN ENDONASAL DCR

    Directory of Open Access Journals (Sweden)

    Koteswar

    2015-11-01

    Full Text Available INTRODUCTION Endoscopic DCR is routinely performed by otolaryngologists for the treatment of chronic dacryocystitis. However, postoperative stenosis and failure rates are common. OBJECTIVE The objective of our study is to evaluate the role of preserving the mucosal flap in maintaining the patency of neo ostium. The surgical technique involved the creation of nasal mucosal and large posterior lacrimal flaps at the medial lacrimal sac wall and the two flaps were placed in close apposition. Success was defined as complete resolution of epiphora and a patent lacrimal system, evaluated by lacrimal irrigation and endoscopy followed upto 1 year postoperatively. MATERIALS AND METHODS A prosective study was conducted in 60 patients and followed for a duration of 1 year in ENT department,KMC,Guntur RESULTS In our study, Symptomatic and anatomic success was seen in 59 out of 60 operations that is 98% success in syringing patency was seen with this technique, which is comparable to external DCR and better than other endoscopic techniques. CONCLUSION Mucosal flap preservation appears to be the single most important innovation in endoscopic DCR surgery, which makes it comfortable for both the surgeon and patient, apart from providing a 98% success rate in our study.

  14. Successful endoscopic endonasal repair of nasal meningoencephalocele in a 21-day-old neonate

    OpenAIRE

    Mohindra, Satyawati; Mohindra, Sandeep; Patro, Sourabha Kumar

    2015-01-01

    Introduction: Indications of surgical intervention in congenital nasal meningoencephaloceles includes presence of cerebro spinal fluid rhinorrhea having a risk of causing meningitis, episodes of prior meningitis and bilateral nasal obstruction causing respiratory difficulty in these obligate nasal breathers. Many authors would like to wait till the patient attains the age of 2 to 3 years for repair of the defect due to surgical feasibility. However, early intervention prevents further episode...

  15. Robot-assisted endoscope guidance versus manual endoscope guidance in functional endonasal sinus surgery (FESS).

    Science.gov (United States)

    Eichhorn, Klaus Wolfgang; Westphal, Ralf; Rilk, Markus; Last, Carsten; Bootz, Friedrich; Wahl, Friedrich; Jakob, Mark; Send, Thorsten

    2017-10-01

    Having one hand occupied with the endoscope is the major disadvantage for the surgeon when it comes to functional endoscopic sinus surgery (FESS). Only the other hand is free to use the surgical instruments. Tiredness or frequent instrument changes can thus lead to shaky endoscopic images. We collected the pose data (position and orientation) of the rigid 0° endoscope and all the instruments used in 16 FESS procedures with manual endoscope guidance as well as robot-assisted endoscope guidance. In combination with the DICOM CT data, we tracked the endoscope poses and workspaces using self-developed tracking markers. All surgeries were performed once with the robot and once with the surgeon holding the endoscope. Looking at the durations required, we observed a decrease in the operating time because one surgeon doing all the procedures and so a learning curve occurred what we expected. The visual inspection of the specimens showed no damages to any of the structures outside the paranasal sinuses. Robot-assisted endoscope guidance in sinus surgery is possible. Further CT data, however, are desirable for the surgical analysis of a tracker-based navigation within the anatomic borders. Our marker-based tracking of the endoscope as well as the instruments makes an automated endoscope guidance feasible. On the subjective side, we see that RASS brings a relief for the surgeon.

  16. Alternative Auditing Approaches

    Energy Technology Data Exchange (ETDEWEB)

    Kandt, Alicen J [National Renewable Energy Laboratory (NREL), Golden, CO (United States)

    2017-09-15

    This presentation for the 2017 Energy Exchange in Tampa, Florida, offers information about advanced auditing technologies and techniques including alternative auditing approaches and considerations and caveats.

  17. Articulating Design Approaches?

    DEFF Research Database (Denmark)

    Kensing, Finn; Bødker, Keld; Simonsen, Jesper

    We are working on an approach for designing CSCW systems since we advocate the importance of generalizing from own work practice as designers and from studies of designers working under industrial conditions. We use the term approach as something in between commodified methods and isolated...... techniques supporting one or a few activities. Our background is computer science. In our design approach we use a combination of intervention and ethnographic techniques. The question for us is how to present our approach: what kind of guidelines and at what level of detail might designers from industry...

  18. Magnetically guided neuronavigation of flexible instruments in shunt placement, transsphenoidal procedures, and craniotomies.

    Science.gov (United States)

    Schichor, Christian; Witte, Jens; Schöller, Karsten; Tanner, Philipp; Uhl, Eberhard; Goldbrunner, Roland; Tonn, Jörg-Christian

    2008-07-01

    Magnetically guided neuronavigation of flexible instruments is a new tool that can be used in the frameless navigation of deep-seated lesions or shunt placements. Disadvantages of optical systems such as the line-of-sight problem, the necessity of rigid pin fixation of the head, and missing tracking of the tip of flexible instruments should be solved by the new tracking system. Until now, the accuracy of magnetically guided systems was mostly estimated in laboratory setups. In this study, intraoperative accuracy of the system was tested in 60 patients with either hydrocephalus or cranial base tumors. In daily routine use, different operative setups with a variety of metallic instruments were examined. Accuracy of the neuronavigation system was estimated, comparing microscopically or endoscopically identified anatomic landmarks with neuronavigated data and postoperative computed tomographic scans. The main advantage of the new system is the tracking of a magnetic coil at the tip of a flexible instrument. After an initial learning curve during the developmental phase of the system, the latter showed reliable accuracy values with no operative setups leading to mismatch of more than 2 mm. Tracking of flexible instruments was easily accomplished as the tip of the instrument was followed within the patient's head. There were no major interferences with other metallic instruments within the surgical field.

  19. Ten practice redesign approaches.

    Science.gov (United States)

    Slayton, Val

    2013-01-01

    As healthcare delivery continues to evolve at a rapid pace, practices need to consider redesign approaches to stay ahead of the pack. From national policy and private payer initiatives to societal macro trends and the growing use of mobile technologies, delivering value, understanding customer needs, and assessing satisfaction are important elements to achieve and maintain success. This article discusses 10 practice redesign approaches.

  20. Approach behavior as information.

    Science.gov (United States)

    van Uijen, Sophie L; van den Hout, Marcel A; Engelhard, Iris M

    2017-12-01

    Anxious individuals infer danger from information about physiological responses, anxiety responses, and safety behaviors. This study investigated whether anxious individuals also infer safety from approach behavior. 325 students rated the danger they perceived in general and spider-relevant scenarios in which information about objective safety versus objective danger, and approach behavior versus no approach behavior, was varied. A high and low spider fearful group was created with a median split on spider fear. Participants with a high fear of spiders, compared to participants with low spider fear, rated spider scenarios with approach behavior as safer than spider scenarios without approach behavior. This effect was similar for objectively dangerous and safe spider scenarios. No behavior as information effects were found for general scenarios. The data were collected in a non-clinical student sample. Spider fearful individuals infer safety from approach behavior in spider-relevant scenarios. For spider fearful individuals, approach behavior may add to the beneficial effects of exposure therapy. Future research is needed to investigate whether patients with anxiety disorders also show a tendency to infer safety from approach behavior. Copyright © 2017 Elsevier Ltd. All rights reserved.

  1. Evaluating six soft approaches

    DEFF Research Database (Denmark)

    Sørensen, Lene; Vidal, Rene Victor Valqui

    2006-01-01

    ’s interactive planning principles to be supported by soft approaches in carrying out the principles in action. These six soft approaches are suitable for supporting various steps of the strategy development and planning process. These are the SWOT analysis, the Future Workshop, the Scenario methodology...

  2. Stuttering-Psycholinguistic Approach

    Science.gov (United States)

    Hategan, Carolina Bodea; Anca, Maria; Prihoi, Lacramioara

    2012-01-01

    This research promotes psycholinguistic paradigm, it focusing in delimitating several specific particularities in stuttering pathology. Structural approach, on language sides proves both the recurrent aspects found within specialized national and international literature and the psycholinguistic approaches dependence on the features of the…

  3. The Geodynamic Approach

    DEFF Research Database (Denmark)

    Steenfelt, Jørgen S.; Ibsen, Lars Bo

    1996-01-01

    The Danish National lecture: The Geodynamic approach - problem or possibility? - mirrors the authors involvement in projects and research focusing on the impact of the geodynamic approach. The lecture discusses the why and how of some of the geotechnical anomalies and the differences in traditional...

  4. Flipped Classroom Approach

    Science.gov (United States)

    Ozdamli, Fezile; Asiksoy, Gulsum

    2016-01-01

    Flipped classroom is an active, student-centered approach that was formed to increase the quality of period within class. Generally this approach whose applications are done mostly in Physical Sciences, also attracts the attention of educators and researchers in different disciplines recently. Flipped classroom learning which wide-spreads rapidly…

  5. The TLC Approach.

    Science.gov (United States)

    Welker, William A.

    2002-01-01

    Notes how the author has developed the Teaching and Learning Cues (TLC) approach, an offspring of textbook organizational patterns instruction that stresses the significance of certain words and phrases in reading. Concludes that with the TLC approach, students learn to appreciate the important role cue words and phrases play in understanding…

  6. Modular Approach for Ethics

    Science.gov (United States)

    Wyne, Mudasser F.

    2010-01-01

    It is hard to define a single set of ethics that will cover an entire computer users community. In this paper, the issue is addressed in reference to code of ethics implemented by various professionals, institutes and organizations. The paper presents a higher level model using hierarchical approach. The code developed using this approach could be…

  7. Evaluating six soft approaches

    DEFF Research Database (Denmark)

    Sørensen, Lene Tolstrup; Vidal, Rene Victor Valqui

    2008-01-01

    's interactive planning principles to be supported by soft approaches in carrying out the principles in action. These six soft approaches are suitable forsupporting various steps of the strategy development and planning process. These are the SWOT analysis, the Future Workshop, the Scenario methodology...

  8. Evaluating Six Soft Approaches

    DEFF Research Database (Denmark)

    Sørensen, Lene Tolstrup; Valqui Vidal, René Victor

    2008-01-01

    's interactive planning principles to be supported by soft approaches in carrying out the principles in action. These six soft approaches are suitable forsupporting various steps of the strategy development and planning process. These are the SWOT analysis, the Future Workshop, the Scenario methodology...

  9. Life Span Developmental Approach

    Directory of Open Access Journals (Sweden)

    Ali Eryilmaz

    2011-03-01

    Full Text Available The Life Span Developmental Approach examines development of individuals which occurs from birth to death. Life span developmental approach is a multi-disciplinary approach related with disciplines like psychology, psychiatry, sociology, anthropology and geriatrics that indicates the fact that development is not completed in adulthood, it continues during the life course. Development is a complex process that consists of dying and death. This approach carefully investigates the development of individuals with respect to developmental stages. This developmental approach suggests that scientific disciplines should not explain developmental facts only with age changes. Along with aging, cognitive, biological, and socioemotional development throughout life should also be considered to provide a reasonable and acceptable context, guideposts, and reasonable expectations for the person. There are three important subjects whom life span developmental approach deals with. These are nature vs nurture, continuity vs discontinuity, and change vs stability. Researchers using life span developmental approach gather and produce knowledge on these three most important domains of individual development with their unique scientific methodology.

  10. Open Versus Closed Septorhinoplasty Approaches for Postoperative Edema and Ecchymosis.

    Science.gov (United States)

    Sakallioğlu, Öner; Cingi, Cemal; Polat, Cahit; Soylu, Erkan; Akyigit, Abdulvahap; Soken, Hakan

    2015-06-01

    The aim of this study was to compare periorbital edema and ecchymosis seen after closed (endonasal) and open (external) septorhinoplasty (SRP). In total, 50 patients undergoing hump extraction and osteotomies were allocated to 2 groups. Group 1 consisted of 25 patients who underwent closed SRP. Group 2 consisted of 25 patients who underwent open SRP. Operation time, amount of intraoperative bleeding, and complications were recorded. Scoring of eyelid edema and periorbital ecchymosis was evaluated on the first, third, and seventh postoperative days using a scale of 0 to 4 by the first author. There was no statistically significant difference between the groups in terms of age, sex, or operation time. No significant difference was observed clinically or statistically in the scores of periorbital edema or ecchymosis between groups 1 and 2 on the first, third, and seventh postoperative days (P > 0.05). The authors observed no clinically or statistically significant difference in comparing periorbital edema and ecchymosis seen after closed and open SRP.

  11. Flipped Classroom Approach

    Directory of Open Access Journals (Sweden)

    Fezile Ozdamli

    2016-07-01

    Full Text Available Flipped classroom is an active, student-centered approach that was formed to increase the quality of period within class. Generally this approach whose applications are done mostly in Physical Sciences, also attracts the attention of educators and researchers in different disciplines recently. Flipped classroom learning which wide-spreads rapidly in the world, is not well recognized in our country. That is why the aim of study is to attract attention to its potential in education field and provide to make it recognize more by educators and researchers. With this aim, in the study what flipped classroom approach is, flipped classroom technology models, its advantages and limitations were explained.

  12. Otoplasty: A graduated approach.

    Science.gov (United States)

    Foda, H M

    1999-01-01

    Numerous otoplastic techniques have been described for the correction of protruding ears. Technique selection in otoplasty should be done only after careful analysis of the abnormal anatomy responsible for the protruding ear deformity. A graduated surgical approach is presented which is designed to address all contributing factors to the presenting auricular deformity. The approach starts with the more conservative cartilage-sparing suturing techniques, then proceeds to incorporate other more aggressive cartilage weakening maneuvers. Applying this approach resulted in better long-term results with less postoperative lateralization than that encountered on using the cartilage-sparing techniques alone.

  13. The Unusual Presentation of a Myxoma Within the Sphenoid Sinus: Case Report and Review of the Literature.

    Science.gov (United States)

    Clarke, Julian V; Mandpe, Aditi H; Weber, Peter B; Vogel, Hannes; Leng, Lewis Z

    2017-07-01

    We describe a rare case of a sphenoid sinus myxoma that was resected via an endoscopic endonasal skull base approach. We review the literature regarding these rare tumors of the paranasal sinuses. A 72-year-old woman was diagnosed with an incidental sphenoid sinus tumor and left sphenoid wing meningioma during a workup for left-sided proptosis and diplopia. Biopsies of the sphenoid wing and sphenoid sinus tumors were obtained. After undergoing surgical resection of the meningioma, the patient then underwent definitive resection of the sphenoid sinus myxoma via endoscopic endonasal skull base approach. Postoperative imaging demonstrated a gross total resection. The patient suffered postoperative thromboembolic complications due to underlying hypercoagulable state but made a complete recovery and returned to her neurologic baseline. There has been no evidence of recurrent myxoma in the sphenoid sinus 24 months after surgery. Myxomas are benign tumors derived from primitive mesenchyme. Myxomas very rarely present in the paranasal or skull base location. Complete surgical resection is the primary treatment for these tumors. The endoscopic endonasal approach is an effective technique for resecting various benign and more aggressive extradural skull base tumors. Myxomas of the sphenoid sinus are rare. The endoscopic endonasal skull base approach is an effective and minimal access technique for resection of this rare tumor of the sphenoid sinus. Copyright © 2017 Elsevier Inc. All rights reserved.

  14. Endoscopic laser ablation of clival chordoma with magnetic resonance-guided laser induced thermal therapy

    Directory of Open Access Journals (Sweden)

    James Barrese

    2014-12-01

    Conclusion: The endoscopic endonasal approach to MRI-guided laser ablation is both technically feasible and safe. As a result, this therapy may be a useful alternative in hard-to-reach chordomas, or in recurrent cases that have failed other conventional treatment modalities.

  15. Sinonasal metallic foreign body penetration of the anterior cranial fossa

    Directory of Open Access Journals (Sweden)

    Madeleine B. Samuelson

    2017-03-01

    Conclusion: Intracranial metallic foreign bodies may have significant potential morbidity. Recent advances in endonasal techniques for anterior skull base access may enhance outcomes through reduced morbidity and mortality, improved speed and precision, shorter hospital stays, and lower post-operative pain [1,2,4]. Technical nuances of these approaches and medical decision-making in the context of various neurosurgical considerations are discussed.

  16. Alternate approach slab reinforcement.

    Science.gov (United States)

    2010-06-01

    The upper mat of reinforcing steel, in exposed concrete bridge approach slabs, is prone to corrosion damage. Chlorides applied to the highways : for winter maintenance can penetrate this concrete layer. Eventually chlorides reach the steel and begin ...

  17. Approach behavior as information

    NARCIS (Netherlands)

    van Uijen, Sophie L.; van den Hout, Marcel A.; Engelhard, Iris M.

    2017-01-01

    Background and objectives Anxious individuals infer danger from information about physiological responses, anxiety responses, and safety behaviors. This study investigated whether anxious individuals also infer safety from approach behavior. Methods 325 students rated the danger they perceived in

  18. RNA/PNA Approach

    Indian Academy of Sciences (India)

    In this approach we want to develop structural analogue of the leader that might have higher affinity towards the Phosphoprotein, but would impair the dimerization process and viral leader RNA binding.

  19. Behavioral based safety approaches

    International Nuclear Information System (INIS)

    Maria Michael Raj, I.

    2009-01-01

    Approach towards the establishment of positive safety culture at Heavy Water Plant, Tuticorin includes the adoption of several important methodologies focused on human behavior and culminates with achievement of Total Safety Culture where Quality and Productivity are integrated with Safety

  20. Multidisciplinary Approaches to Allergies

    NARCIS (Netherlands)

    Gao Zhongshan,; Shen, Hua-Hao; Zheng, M.; Frewer, L.J.; Gilissen, L.J.W.J.

    2012-01-01

    Allergy is an immunological disease caused by multiple factors and characterized by variability, specificity and complexity. "Multidisciplinary Approaches to Allergies" covers diverse aspects ranging from basic molecular mechanisms to societal issues within the framework of multidisciplinary

  1. Climate Change Adaptation Approaches

    Science.gov (United States)

    2011-05-11

    US Army Corps of Engineers BUILDING STRONG® Climate Change Adaptation Approaches Presented at the E2S2 Symposium May 11th, 2011 New Orleans, LA...COVERED 00-00-2011 to 00-00-2011 4. TITLE AND SUBTITLE Climate Change Adaptation Approaches 5a. CONTRACT NUMBER 5b. GRANT NUMBER 5c. PROGRAM...10/09).  One of the four priorities is to maintain readiness in the face of climate change .  Addressing Climate Change Risk and Vulnerability: a

  2. The Knowledge Governance Approach

    DEFF Research Database (Denmark)

    Foss, Nicolai J.

    An attempt is made to characterize a `knowledge governance approach' as a distinctive, emerging field that cuts across the fields of knowledge management, organisation studies, strategy and human resource management. Knowledge governance is taken up with how the deployment of administrative...... with diverse capabilities of handling these transactions. Various open research issues that a knowledge governance approach may illuminate are sketched. Although knowledge governance draws clear inspiration from organizational economics and `rational' organization theory, it recognizes that knowledge...

  3. Theoretical Approaches to Coping

    Directory of Open Access Journals (Sweden)

    Sofia Zyga

    2013-01-01

    Full Text Available Introduction: Dealing with stress requires conscious effort, it cannot be perceived as equal to individual's spontaneous reactions. The intentional management of stress must not be confused withdefense mechanisms. Coping differs from adjustment in that the latter is more general, has a broader meaning and includes diverse ways of facing a difficulty.Aim: An exploration of the definition of the term "coping", the function of the coping process as well as its differentiation from other similar meanings through a literature review.Methodology: Three theoretical approaches of coping are introduced; the psychoanalytic approach; approaching by characteristics; and the Lazarus and Folkman interactive model.Results: The strategic methods of the coping approaches are described and the article ends with a review of the approaches including the functioning of the stress-coping process , the classificationtypes of coping strategies in stress-inducing situations and with a criticism of coping approaches.Conclusions: The comparison of coping in different situations is difficult, if not impossible. The coping process is a slow process, so an individual may select one method of coping under one set ofcircumstances and a different strategy at some other time. Such selection of strategies takes place as the situation changes.

  4. Approaching a Postcolonial Arctic

    DEFF Research Database (Denmark)

    Jensen, Lars

    2016-01-01

    This article explores different postcolonially configured approaches to the Arctic. It begins by considering the Arctic as a region, an entity, and how the customary political science informed approaches are delimited by their focus on understanding the Arctic as a region at the service of the co......This article explores different postcolonially configured approaches to the Arctic. It begins by considering the Arctic as a region, an entity, and how the customary political science informed approaches are delimited by their focus on understanding the Arctic as a region at the service...... of the contemporary neoliberal order. It moves on to explore how different parts of the Arctic are inscribed in a number of sub-Arctic nation-state binds, focusing mainly on Canada and Denmark. The article argues that the postcolonial can be understood as a prism or a methodology that asks pivotal questions to all...... approaches to the Arctic. Yet the postcolonial itself is characterised by limitations, not least in this context its lack of interest in the Arctic, and its bias towards conventional forms of representation in art. The article points to the need to develop a more integrated critique of colonial and neo...

  5. Life History Approach

    DEFF Research Database (Denmark)

    Olesen, Henning Salling

    2015-01-01

    of the social and the psychic, both in the interpretation procedure and in some main theoretical understandings of language, body and mind. My article will present the reflections on the use of life history based methodology in learning and education research as a kind of learning story of research work....... as in everyday life. Life histories represent lived lives past, present and anticipated future. As such they are interpretations of individuals’ experiences of the way in which societal dynamics take place in the individual body and mind, either by the individual him/herself or by another biographer. The Life...... History approach was developing from interpreting autobiographical and later certain other forms of language interactive material as moments of life history, i.e. it is basically a hermeneutic approach. Talking about a psycho-societal approach indicates the ambition of attacking the dichotomy...

  6. Revitalizing the setting approach

    DEFF Research Database (Denmark)

    Bloch, Paul; Toft, Ulla; Reinbach, Helene Christine

    2014-01-01

    BackgroundThe concept of health promotion rests on aspirations aiming at enabling people to increase control over and improve their health. Health promotion action is facilitated in settings such as schools, homes and work places. As a contribution to the promotion of healthy lifestyles, we have......-based. Based on a presentation of ¿Health and Local Community¿, a supersetting initiative addressing the prevention of lifestyle diseases in a Danish municipality, the paper discusses the potentials and challenges of supporting local community interventions using the supersetting approach...... impact of supersetting initiatives. The supersetting approach is an ecological approach, which places the individual in a social, environmental and cultural context, and calls for a holistic perspective to change potentials and developmental processes with a starting point in the circumstances of people...

  7. Technical approach document

    International Nuclear Information System (INIS)

    1989-12-01

    The Uranium Mill Tailings Radiation Control Act (UMTRCA) of 1978, Public Law 95-604 (PL95-604), grants the Secretary of Energy the authority and responsibility to perform such actions as are necessary to minimize radiation health hazards and other environmental hazards caused by inactive uranium mill sites. This Technical Approach Document (TAD) describes the general technical approaches and design criteria adopted by the US Department of Energy (DOE) in order to implement remedial action plans (RAPS) and final designs that comply with EPA standards. It does not address the technical approaches necessary for aquifer restoration at processing sites; a guidance document, currently in preparation, will describe aquifer restoration concerns and technical protocols. This document is a second revision to the original document issued in May 1986; the revision has been made in response to changes to the groundwater standards of 40 CFR 192, Subparts A--C, proposed by EPA as draft standards. New sections were added to define the design approaches and designs necessary to comply with the groundwater standards. These new sections are in addition to changes made throughout the document to reflect current procedures, especially in cover design, water resources protection, and alternate site selection; only minor revisions were made to some of the sections. Sections 3.0 is a new section defining the approach taken in the design of disposal cells; Section 4.0 has been revised to include design of vegetated covers; Section 8.0 discusses design approaches necessary for compliance with the groundwater standards; and Section 9.0 is a new section dealing with nonradiological hazardous constituents. 203 refs., 18 figs., 26 tabs

  8. [Endoscopic transnasal surgery for giant fibrous dysplasia of the skull base, spreading to the right orbital cavity and nasopharynx (a case report and literature review)].

    Science.gov (United States)

    Shkarubo, A N; Lubnin, A Yu; Bukharin, E Yu; Shishkina, L V; Andreev, D N; Koval', K V; Chernov, I V; Karnaukhov, V V

    An extended endoscopic endonasal approach is increasingly used in surgical treatment of space-occupying skull base lesions. The international literature reports only 20 cases of surgical treatment for fibrous dysplasia (PD) of the skull base using the endoscopic endonasal approach. We present our experience with the endoscopic endonasal approach in surgical treatment for giant fibrous dysplasia of the skull base, spreading to the right orbital cavity and nasopharynx. A 26-year-old male patient presented with cranial pain, Vth nerve dysfunction on the right, right keratopathy. OD=0.2 (near acuity - 0.3), OS=1.0, OD - incomplete eyelid closure of 2 mm, conjunctival injection, mucous discharge, corneal opacity in the lower pole and paracentrally, OS - normal appearance. Severe right-sided exophthalmos (more than 15 mm), impaired nasal breathing on the right, nasal (hemorrhagic) discharge. Magnetic resonance imaging and spiral computed tomography scans revealed a bone density lesion located in the area of the orbit, nasal cavity, maxillary sinus on the right, and labyrinth of the ethmoid bone. The patient underwent endonasal endoscopic resection of the lesion. The lesion was resected totally, which was confirmed by control SCT. Right-sided exophthalmos partially regressed (on the right: exophthalmos of 8 mm; protrusion: OD=23 mm, OS=15 mm; the eyeball was displaced downward and outward). The visual and oculomotor functions did not change. The neurological status remained at the preoperative level. Fibrous dysplasia of the skull base is an extremely rare disease. Modern techniques expand the indications for surgery of giant tumors of the skull base using minimally invasive approaches, in particular the endoscopic endonasal approach.

  9. Financial Management: An Organic Approach

    Science.gov (United States)

    Laux, Judy

    2013-01-01

    Although textbooks present corporate finance using a topical approach, good financial management requires an organic approach that integrates the various assignments financial managers confront every day. Breaking the tasks into meaningful subcategories, the current article offers one approach.

  10. Implementation of Communicative Approach

    Science.gov (United States)

    Jabeen, Shazi Shah

    2014-01-01

    In the contemporary age of high professional requirements such as excellent communicative skills, the need for successful learning of communicative skills of English language suggests communicative ability to be the goal of language teaching. In other words, to teach English language using communicative approach becomes essential. Studies to…

  11. Salt repository design approach

    International Nuclear Information System (INIS)

    Matthews, S.C.

    1983-01-01

    This paper presents a summary discussion of the approaches that have been and will be taken in design of repository facilities for use with disposal of radioactive wastes in salt formations. Since specific sites have yet to be identified, the discussion is at a general level, supplemented with illustrative examples where appropriate. 5 references, 1 figure

  12. Marxian Approaches to Education.

    Science.gov (United States)

    Carnoy, Martin

    Traditional Marxist approaches to the state relegate superstructural institutions like the school to a minor role in the process of social change. More recent theories like those of Gramsci, Althusser, and Poulantzas raise the state and the class struggle in the state apparatuses to a much more prominent position: superstructure, including the…

  13. Adopting a Pluricentric Approach

    Science.gov (United States)

    van Kerckvoorde, Colette

    2012-01-01

    This article argues for a "D-A-CH" approach, which stands for Germany (D), Austria (A), and Switzerland (CH), in language classes from the introductory level on. I begin by tracing the emergence and development of distinct Standard Swiss and Austrian German varieties. I then discuss marketing efforts for Swiss and Austrian German, and…

  14. A Personal Approach.

    Science.gov (United States)

    Breunlin, Douglas C.; Lieber, Carol Miller; Simon, Lynn; Cimmarusti, Rocco. A.

    2002-01-01

    Preventing high school violence takes more than security measures alone. Problem-solving approaches involve skill-building strategies that teach students conflict-resolution skills that become alternatives to the use of violence. Peace-making strategies seek to improve school climate by targeting key relationships in the school. Lists eight steps…

  15. Towards a Dual Approach

    DEFF Research Database (Denmark)

    Holli, Anne Maria; Harder, Mette Marie Stæhr

    2016-01-01

    Drawing on insights from state feminism and legislative studies on parliamentary committees, this article develops a dual approach for the comparative analysis of committees on gender equality. Empirically, it compares the standing committees on gender equality in Denmark and Finland, two Nordic...

  16. A variational approach

    Indian Academy of Sciences (India)

    We study the optical switching of the two-dimensional nonlinear coupler in a doped photopolymer. The coupled ... Optical switching; variational approach; Jacobi's elliptic function; surface plasmon resonance ..... [4] G P Agrawal, Applications of nonlinear fiber optics (Academic Press, New York,. 2006). [5] R G Hunsperger ...

  17. Orion Emergency Mask Approach

    Science.gov (United States)

    Tuan, George C.; Graf, John C.

    2009-01-01

    Emergency mask approach on Orion poses a challenge to the traditional Shuttle or Station approaches. Currently, in the case of a fire or toxic spill event, the crew utilizes open loop oxygen masks that provide the crew with oxygen to breath, but also dumps the exhaled oxygen into the cabin. For Orion, with a small cabin volume, the extra oxygen will exceed the flammability limit within a short period of time, unless a nitrogen purge is also provided. Another approach to a fire or toxic spill event is the use of a filtering emergency masks. These masks utilize some form of chemical beds to scrub the air clean of toxic providing the crew safe breathing air for a period without elevating the oxygen level in the cabin. Using the masks and a form of smoke-eater filter, it may be possible to clean the cabin completely or to a level for safe transition to a space suit to perform a cabin purge. Issues with filters in the past have been the reaction time, breakthroughs, and high breathing resistance. Development in a new form of chemical filters has shown promise to make the filtering approach feasible.

  18. Health: An Ecosystem Approach

    International Development Research Centre (IDRC) Digital Library (Canada)

    A sectoral approach is no longer adequate: co-management of human activity and the environment is essential. .... Suceeding in a transdisciplinary initiative requires defining a research protocol (Box 1), finding ways of integrating the community in problem definition, and ascribing appropriate importance to the various ...

  19. Approach to Absolute Zero

    Indian Academy of Sciences (India)

    Home; Journals; Resonance – Journal of Science Education; Volume 2; Issue 6. Approach to Absolute Zero 0.3 K. to a Few Milli-Kelvin. R Srinivasan. Series Article Volume 2 Issue 6 June 1997 pp 6-14. Fulltext. Click here to view fulltext PDF. Permanent link: http://www.ias.ac.in/article/fulltext/reso/002/06/0006-0014 ...

  20. Approach to Absolute Zero

    Indian Academy of Sciences (India)

    Home; Journals; Resonance – Journal of Science Education; Volume 2; Issue 2. Approach to Absolute Zero From 4. 22 K. to 0. 3 K. R Srinivasan. Series Article Volume 2 Issue 2 February 1997 pp 8-16. Fulltext. Click here to view fulltext PDF. Permanent link: http://www.ias.ac.in/article/fulltext/reso/002/02/0008-0016 ...

  1. Approach to Absolute Zero

    Indian Academy of Sciences (India)

    Home; Journals; Resonance – Journal of Science Education; Volume 2; Issue 10. Approach to Absolute Zero Below 10 milli-Kelvin. R Srinivasan. Series Article Volume 2 Issue 10 October 1997 pp 8-16. Fulltext. Click here to view fulltext PDF. Permanent link: http://www.ias.ac.in/article/fulltext/reso/002/10/0008-0016 ...

  2. Comparing Information Access Approaches.

    Science.gov (United States)

    Chalmers, Matthew

    1999-01-01

    Presents a broad view of information access, drawing from philosophy and semiology in constructing a framework for comparative discussion that is used to examine the information representations that underlie four approaches to information access--information retrieval, workflow, collaborative filtering, and the path model. Contains 32 references.…

  3. Thematic curriculum approach

    Directory of Open Access Journals (Sweden)

    Šefer Jasmina P.

    2003-01-01

    Full Text Available Thematic curriculum combines disciplines and media. The process is problem-oriented and the scenario most often follows the logic of exploring or storytelling. Those two approaches to teaching are appropriate because they fit into interdisciplinary and creative open-ended problem solving through play, as insisted upon by thematic curriculum. The matrix, where seven types of abilities intersect with five types of problems according to their degree of openness, defines well the outcomes of teaching. However, it did not prove to be suitable for planning the majority of activities in thematic curriculum, for it follows with difficulty the process of exploring or storytelling i.e. it disrupts the subject matter coherence of thematic curriculum. Therefore, it is suggested that matrix should be used for disciplinary curriculum planning but for that of thematic curriculum only in exclusive cases. The matrix should be used primarily as a framework for evaluating the distribution of various types of abilities and problem situations in teaching. The logic of diverse approaches to teaching reflects itself in the manner of planning and organizing the teaching process. Conceptual, visual-graphic, structural and other aids employed during educational process planning should suit the nature of the approach chosen. On the basis of qualitative investigations of educational process, in the present paper considerations are given to various approaches to teaching development of various drafts for the planning of teaching, and recognition of the logic of storytelling and exploring in thematic curriculum.

  4. NEW APPROACHES: Toppling trains

    Science.gov (United States)

    Parry, Malcolm

    1998-03-01

    This article explains a novel way of approaching centripetal force: theory is used to predict an orbital period at which a toy train will topple from a circular track. The demonstration has proved useful in A-level, GNVQ and undergraduate Physics and Engineering schemes.

  5. The Capability Approach

    NARCIS (Netherlands)

    I.A.M. Robeyns (Ingrid)

    2011-01-01

    textabstract In its most general description, the capability approach is a flexible and multi-purpose normative framework, rather than a precise theory of well-being, freedom or justice. At its core are two normative claims: first, the claim that the freedom to achieve well-being is of primary

  6. Approaches to acceptable risk

    International Nuclear Information System (INIS)

    Whipple, C.

    1997-01-01

    Several alternative approaches to address the question open-quotes How safe is safe enough?close quotes are reviewed and an attempt is made to apply the reasoning behind these approaches to the issue of acceptability of radiation exposures received in space. The approaches to the issue of the acceptability of technological risk described here are primarily analytical, and are drawn from examples in the management of environmental health risks. These include risk-based approaches, in which specific quantitative risk targets determine the acceptability of an activity, and cost-benefit and decision analysis, which generally focus on the estimation and evaluation of risks, benefits and costs, in a framework that balances these factors against each other. These analytical methods tend by their quantitative nature to emphasize the magnitude of risks, costs and alternatives, and to downplay other factors, especially those that are not easily expressed in quantitative terms, that affect acceptance or rejection of risk. Such other factors include the issues of risk perceptions and how and by whom risk decisions are made

  7. Approach to Absolute Zero

    Indian Academy of Sciences (India)

    Home; Journals; Resonance – Journal of Science Education; Volume 2; Issue 10. Approach to Absolute Zero Below 10 milli-Kelvin. R Srinivasan. Series Article Volume 2 Issue 10 October 1997 pp 8-16. Fulltext. Click here to view fulltext PDF. Permanent link: https://www.ias.ac.in/article/fulltext/reso/002/10/0008-0016 ...

  8. Fuel cycle oriented approach

    International Nuclear Information System (INIS)

    Petit, A.

    1987-01-01

    The term fuel cycle oriented approach is currently used to designate two quite different things: the attempt to consider all or part of a national fuel cycle as one material balance area (MBA) or to consider individual MBAs existing in a state while designing a unique safeguards approach for each and applying the principle of nondiscrimination to fuel cycles as a whole, rather than to individual facilities. The merits of such an approach are acceptability by the industry and comparison with the contemplated establishment of long-term criteria. The following points concern the acceptability by the industry: (1) The main interest of the industry is to keep an open international market and therefore, to have effective and efficient safeguards. (2) The main concerns of the industry regarding international safeguards are economic burden, intrusiveness, and discrimination. Answers to these legitimate concerns, which retain the benefits of a fuel cycle oriented approach, are needed. More specifically, the problem of reimbursing the operator the costs that he has incurred for the safeguards must be considered

  9. Ecosystem approach in education

    Science.gov (United States)

    Nabiullin, Iskander

    2017-04-01

    Environmental education is a base for sustainable development. Therefore, in our school we pay great attention to environmental education. Environmental education in our school is based on ecosystem approach. What is an ecosystem approach? Ecosystem is a fundamental concept of ecology. Living organisms and their non-living environments interact with each other as a system, and the biosphere planet functions as a global ecosystem. Therefore, it is necessary for children to understand relationships in ecosystems, and we have to develop systems thinking in our students. Ecosystem approach and systems thinking should help us to solve global environmental problems. How do we implement the ecosystem approach? Students must understand that our biosphere functions as a single ecosystem and even small changes can lead to environmental disasters. Even the disappearance of one plant or animal species can lead to irreversible consequences. So in the classroom we learn the importance of each living organism for the nature. We pay special attention to endangered species, which are listed in the Red Data List. Kids are doing projects about these organisms, make videos, print brochures and newspapers. Fieldwork also plays an important role for ecosystem approach. Every summer, we go out for expeditions to study species of plants and animals listed in the Red Data List of Tatarstan. In class, students often write essays on behalf of any endangered species of plants or animals, this also helps them to understand the importance of each living organism in nature. Each spring we organise a festival of environmental projects among students. Groups of 4-5 students work on a solution of environmental problems, such as water, air or soil pollution, waste recycling, the loss of biodiversity, etc. Participants shoot a clip about their project, print brochures. Furthermore, some of the students participate in national and international scientific Olympiads with their projects. In addition to

  10. Domain Approach: An Alternative Approach in Moral Education

    Science.gov (United States)

    Vengadasalam, Chander; Mamat, Wan Hasmah Wan; Mail, Fauziah; Sudramanian, Munimah

    2014-01-01

    This paper discusses the use of the domain approach in moral education in an upper secondary school in Malaysia. Moral Education needs a creative and an innovative approach. Therefore, a few forms of approaches are used in the teaching-learning of Moral Education. This research describes the use of domain approach which comprises the moral domain…

  11. Phase Field Approach

    Science.gov (United States)

    Koyama, Toshiyuki

    The term phase field has recently become known across many fields of materials science. The meaning of phase field is the spatial and temporal order parameter field defined in a continuum-diffused interface model. By using the phase field order parameters, many types of complex microstructure changes observed in materials science are described effectively. This methodology has been referred to as the phase field method, phase field simulation, phase field modeling, phase field approach, etc. In this chapter, the basic concept and theoretical background for the phase field approach is explained in Sects. 21.1 and 21.2. The overview of recent applications of the phase field method is demonstrated in Sects. 21.3 to 21.6.

  12. Microscopic approach to polaritons

    DEFF Research Database (Denmark)

    Skettrup, Torben

    1981-01-01

    The interaction between excitons and light has been investigated in detail. The perturbational approach turns out to be invalid. However, an exact solution can be obtained directly from the Schrödinger equation for a fixed light field. This solution corresponds to a nonlinear optical response...... contrary to experimental experience. In order to remove this absurdity the semiclassical approach must be abandoned and the electromagnetic field quantized. A simple microscopic polariton model is then derived. From this the wave function for the interacting exciton-photon complex is obtained...... of light of the crystal. The introduction of damping smears out the excitonic spectra. The wave function of the polariton, however, turns out to be very independent of damping up to large damping values. Finally, this simplified microscopic polariton model is compared with the exact solutions obtained...

  13. Transaction based approach

    Science.gov (United States)

    Hunka, Frantisek; Matula, Jiri

    2017-07-01

    Transaction based approach is utilized in some methodologies in business process modeling. Essential parts of these transactions are human beings. The notion of agent or actor role is usually used for them. The paper on a particular example describes possibilities of Design Engineering Methodology for Organizations (DEMO) and Resource-Event-Agent (REA) methodology. Whereas the DEMO methodology can be regarded as a generic methodology having its foundation in the theory of Enterprise Ontology the REA methodology is regarded as the domain specific methodology and has its origin in accountancy systems. The results of these approaches is that the DEMO methodology captures everything that happens in the reality with a good empirical evidence whereas the REA methodology captures only changes connected with economic events. Economic events represent either change of the property rights to economic resource or consumption or production of economic resources. This results from the essence of economic events and their connection to economic resources.

  14. The quality systems approach.

    Science.gov (United States)

    Nevalainen, D E

    1999-07-01

    Health care as an industry is going through an evolution similar to that experienced by manufacturing and other service sectors of the world economy. When competition threatens, the traditional management approach is slash-and-burn to manage costs. This approach affects people, services, and facilities. When the slash-and-burn method runs out of fuel, organizations start to merge, thinking that bigger is better. Just getting bigger only looks like change, with a new cast of fewer people and organizational structure. The root cause for existing problems has not been fixed. The only real solution, as manufacturing and services learned, is to understand and improve work processes to ensure that the right work is being done in a high-quality manner and at a competitive price. The era of quality systems is just dawning in health care. The focus must remain on quality patient outcomes at a competitive price by improving supporting systems and processes to accomplish these goals.

  15. Approach to reliability assessment

    International Nuclear Information System (INIS)

    Green, A.E.; Bourne, A.J.

    1975-01-01

    Experience has shown that reliability assessments can play an important role in the early design and subsequent operation of technological systems where reliability is at a premium. The approaches to and techniques for such assessments, which have been outlined in the paper, have been successfully applied in variety of applications ranging from individual equipments to large and complex systems. The general approach involves the logical and systematic establishment of the purpose, performance requirements and reliability criteria of systems. This is followed by an appraisal of likely system achievment based on the understanding of different types of variational behavior. A fundamental reliability model emerges from the correlation between the appropriate Q and H functions for performance requirement and achievement. This model may cover the complete spectrum of performance behavior in all the system dimensions

  16. Rail transport systems approach

    CERN Document Server

    2017-01-01

    This book shows how the systems approach is employed by scientists in various countries to solve specific problems concerning railway transport. In particular, the book describes the experiences of scientists from Romania, Germany, the Czech Republic, the UK, Russia, Ukraine, Lithuania and Poland. For many of these countries there is a problem with the historical differences between the railways. In particular, there are railways with different rail gauges, with different signaling and communication systems, with different energy supplies and, finally, with different political systems, which are reflected in the different approaches to the management of railway economies. The book’s content is divided into two main parts, the first of which provides a systematic analysis of individual means of providing and maintaining rail transport. In turn, the second part addresses infrastructure and management development, with particular attention to security issues. Though primarily written for professionals involved...

  17. Thermodynamics an engineering approach

    CERN Document Server

    Cengel, Yunus A

    2014-01-01

    Thermodynamics, An Engineering Approach, eighth edition, covers the basic principles of thermodynamics while presenting a wealth of real-world engineering examples so students get a feel for how thermodynamics is applied in engineering practice. This text helps students develop an intuitive understanding by emphasizing the physics and physical arguments. Cengel and Boles explore the various facets of thermodynamics through careful explanations of concepts and use of numerous practical examples and figures, having students develop necessary skills to bridge the gap between knowledge and the confidence to properly apply their knowledge. McGraw-Hill is proud to offer Connect with the eighth edition of Cengel/Boles, Thermodynamics, An Engineering Approach. This innovative and powerful new system helps your students learn more efficiently and gives you the ability to assign homework problems simply and easily. Problems are graded automatically, and the results are recorded immediately. Track individual stude...

  18. Dimensional Approach in Psychiatry

    Directory of Open Access Journals (Sweden)

    Osman Ozdemir

    2012-09-01

    Full Text Available In psychiatry there is a traditional categorical conception stating that several disorders like schizophrenia and bipolar disorder have distinct etiologies. On the other hand, dimensional approach claims that these entities are actually the same disorder reflecting different clinical aspects of same mental disorder in the course of time. ICD and DSM classifications are based on separate categories of different mental disorders. Howewer, it is quite difficult to consider a mental disorder as a discrete entity that has absolute boundaries from other disorders. There are patients manifesting symptoms of two or more categories but do not fulfill all diagnostic criteria for any mental disorder. Dimensional approach handles the psychopathology as a continuing process and establish the patients to the different ongoing points. According to this view, in fact, multiple diagnosis reflect dimensions of the same disease.

  19. Electronics a systems approach

    CERN Document Server

    Storey, Neil

    2017-01-01

    Electronics plays a central role in our everyday lives. It is at the heart of almost all of today's essential technology, from mobile phones to computers and from cars to power stations. As such, all engineers, scientists and technologists need to have a fundamental understanding of this exciting subject, and for many this will just be the beginning. Now in its sixth edition, Electronics: A Systems Approach provides an outstanding introduction to this fast-moving and important field. Comprehensively revised and updated to cover the latest developments in the world of electronics, the text continues to use Neil Storey's established and well-respected systems approach. It introduces the basic concepts first before progressing to a more advanced analysis, enabling you to contextualise what a system is designed to achieve before tackling the intricacies of designing or analysing its various components with confidence. This book is accompanied by a website which contains over 100 video tutorials to help explain ke...

  20. Approaching Service Innovation Patterns

    OpenAIRE

    NAGY Andrea

    2013-01-01

    The present paper aims at analyzing the types of innovation in the field of services. First, the concept of innovation is defined and second, field literature is reviewed from the perspective of service innovation. The main types of innovation are identified based on several attempts at defining innovation, the most notable being Schumpeter’s. Thus, it is possible to approach concepts such as product and process innovation, incremental and radical innovation. Another aim has been to regard se...

  1. Breakfast: a multidisciplinary approach

    OpenAIRE

    Affinita, Antonio; Catalani, Loredana; Cecchetto, Giovanna; De Lorenzo, Gianfranco; Dilillo, Dario; Donegani, Giorgio; Fransos, Lucia; Lucidi, Fabio; Mameli, Chiara; Manna, Elisa; Marconi, Paolo; Mele, Giuseppe; Minestroni, Laura; Montanari, Massimo; Morcellini, Mario

    2013-01-01

    Background The role of breakfast as an essential part of an healthy diet has been only recently promoted even if breakfast practices were known since the Middle Age. The growing scientific evidences on this topic are extremely sector-based nevertheless breakfast could be regarded from different point of views and from different expertises. This approach, that take into account history, sociology, anthropology, medicine, psychology and pedagogy, is useful to better understand the value of this...

  2. STRATEGIC INNOVATION APPROACH

    OpenAIRE

    Dogan, Nilhun

    2017-01-01

    In recentyears, the concept of innovation has become the most debated topic inliterature and in particular, the strategic importance of innovation managementfor businesses is emphasized. In this context, the strategic innovationapproach, which emerged as a synergy of innovation and strategic management,seems to play an important role in achieving sustainable competitive advantage.The aim of this article is to emphasize the importance of innovation andstrategic innovation approach.  

  3. [Approaches to radial shaft].

    Science.gov (United States)

    Bartoníček, J; Naňka, O; Tuček, M

    2015-10-01

    In the clinical practice, radial shaft may be exposed via two approaches, namely the posterolateral Thompson and volar (anterior) Henry approaches. A feared complication of both of them is the injury to the deep branch of the radial nerve. No consensus has been reached, yet, as to which of the two approaches is more beneficial for the proximal half of radius. According to our anatomical studies and clinical experience, Thompson approach is safe only in fractures of the middle and distal thirds of the radial shaft, but highly risky in fractures of its proximal third. Henry approach may be used in any fracture of the radial shaft and provides a safe exposure of the entire lateral and anterior surfaces of the radius.The Henry approach has three phases. In the first phase, incision is made along the line connecting the biceps brachii tendon and the styloid process of radius. Care must be taken not to damage the lateral cutaneous nerve of forearm.In the second phase, fascia is incised and the brachioradialis identified by the typical transition from the muscle belly to tendon and the shape of the tendon. On the lateral side, the brachioradialis lines the space with the radial artery and veins and the superficial branch of the radial nerve running at its bottom. On the medial side, the space is defined by the pronator teres in the proximal part and the flexor carpi radialis in the distal part. The superficial branch of the radial nerve is retracted together with the brachioradialis laterally, and the radial artery medially.In the third phase, the attachment of the pronator teres is identified by its typical tendon in the middle of convexity of the lateral surface of the radial shaft. The proximal half of the radius must be exposed very carefully in order not to damage the deep branch of the radial nerve. Dissection starts at the insertion of the pronator teres and proceeds proximally along its lateral border in interval between this muscle and insertion of the supinator

  4. Peritonitis: laparoscopic approach

    Directory of Open Access Journals (Sweden)

    Agresta Ferdinando

    2006-03-01

    Full Text Available Abstract Background Laparoscopy has became as the preferred surgical approach to a number of different diseases because it allows a correct diagnosis and treatment at the same time. In abdominal emergencies, both components of treatment – exploration to identify the causative pathology and performance of an appropriate operation – can often be accomplished via laparoscopy. There is still a debate of peritonitis as a contraindication to this kind of approach. Aim of the present work is to illustrate retrospectively the results of a case-control experience of laparoscopic vs. open surgery for abdominal peritonitis emergencies carried out at our institution. Methods From January 1992 and January 2002 a total of 935 patients (mean age 42.3 ± 17.2 years underwent emergent and/or urgent surgery. Among them, 602 (64.3% were operated on laparoscopically (of whom 112 -18.7% – with peritonitis, according to the presence of a surgical team trained in laparoscopy. Patients with a history of malignancy, more than two previous major abdominal surgeries or massive bowel distension were not treated Laparoscopically. Peritonitis was not considered contraindication to Laparoscopy. Results The conversion rate was 23.2% in patients with peritonitis and was mainly due to the presence of dense intra-abdominal adhesions. Major complications ranged as high as 5.3% with a postoperative mortality of 1.7%. A definitive diagnosis was accomplished in 85.7% (96 pat. of cases, and 90.6% (87 of these patients were treated successfully by Laparoscopy. Conclusion Even if limited by its retrospective feature, the present experience let us to consider the Laparoscopic approach to abdominal peritonitis emergencies a safe and effective as conventional surgery, with a higher diagnostic yield and allows for lesser trauma and a more rapid postoperative recovery. Such features make Laparoscopy a challenging alternative to open surgery in the management algorithm for abdominal

  5. New Encrypted Steganography Approach

    Directory of Open Access Journals (Sweden)

    Saba Mohammed Husain‎

    2017-12-01

    Full Text Available The proposed research Provides an approach for hiding an encrypted text in side a digital image. Where the text is encrypted in a complex manner used method of PlayFair to encrypt clear text and to increase security put lettering ciphertext on the geometric shape clockwise and then we write the ciphertext output in the form of lines, taken new ciphertext and converted to Ascii code and then to binary and hidden text in bits least importance in the picture. The results were good by PNSR scale

  6. HEDR modeling approach

    International Nuclear Information System (INIS)

    Shipler, D.B.; Napier, B.A.

    1992-07-01

    This report details the conceptual approaches to be used in calculating radiation doses to individuals throughout the various periods of operations at the Hanford Site. The report considers the major environmental transport pathways--atmospheric, surface water, and ground water--and projects and appropriate modeling technique for each. The modeling sequence chosen for each pathway depends on the available data on doses, the degree of confidence justified by such existing data, and the level of sophistication deemed appropriate for the particular pathway and time period being considered

  7. The collaboratory approach

    Energy Technology Data Exchange (ETDEWEB)

    Peskin, A.M.

    1997-04-01

    A {open_quotes}collaboratory{close_quotes} has been defined as a center without walls, in which researchers can perform their work without regard to geographical location. To an increasing degree, engineering design and development is also taking the form of far-flung collaborations among divisions of a plant, subcontractors, university consultants and customers. It has long been recognized that quality engineering education presents the student with an environment that duplicates as much as possible that which the graduate will encounter in industry. To that end, it is important that engineering schools begin to introduce the collaboratory approach in its preparation, and even use it in delivery of subject matter to students.

  8. The collaboratory approach

    International Nuclear Information System (INIS)

    Peskin, A.M.

    1997-01-01

    A open-quotes collaboratoryclose quotes has been defined as a center without walls, in which researchers can perform their work without regard to geographical location. To an increasing degree, engineering design and development is also taking the form of far-flung collaborations among divisions of a plant, subcontractors, university consultants and customers. It has long been recognized that quality engineering education presents the student with an environment that duplicates as much as possible that which the graduate will encounter in industry. To that end, it is important that engineering schools begin to introduce the collaboratory approach in its preparation, and even use it in delivery of subject matter to students

  9. Experimental approaches and applications

    CERN Document Server

    Crasemann, Bernd

    1975-01-01

    Atomic Inner-Shell Processes, Volume II: Experimental Approaches and Applications focuses on the physics of atomic inner shells, with emphasis on experimental aspects including the use of radioactive atoms for studies of atomic transition probabilities. Surveys of modern techniques of electron and photon spectrometry are also presented, and selected practical applications of inner-shell processes are outlined. Comprised of six chapters, this volume begins with an overview of the general principles underlying the experimental techniques that make use of radioactive isotopes for inner-sh

  10. URBAN POLITICS: KEY APPROACHES

    Directory of Open Access Journals (Sweden)

    Ledyaeva Ol'ga Mikhaylovna

    2012-10-01

    Full Text Available Several approaches that underlie urban politics are discussed in the paper. They include neo-liberalism, political economy discourse, elitist/pluralist debates, and postmodernism. The neoliberal approach focuses on the limited role of the state and individual responsibility. The legal framework protects both the rights and responsibilities of individuals and regulates the operation of the market. It is the market that fosters individual choices and provides goods and services by virtue of the processes which are flexible, efficient and transparent. The political economy approaches (regulation theory, public choice theory, neo-Marxism explain urban politics via the analysis of national and international economic processes and changes in contemporary capitalism. Changes in national and international economies determine what solutions are possible. The discourse has been influenced by the debate on globalization of capital and labour markets. Modern elitism and neopluralism are represented by theories of "growth machines" and "urban regimes". The former focuses on bargaining alliances between political and business leaders in order to manage the urban system and to promote its growth. The latter develops neopluralist explanations of power within local communities with an emphasis on the fragmented nature of the government where local authorities lack comprehensive governing powers. Postmodernism views the city as the site of the crisis of late capitalism which leads to segregation of neighbourhoods onto prosperous areas and ghettoes. In contrast to the modern city, the postmodern city is not defined by its industrial base; rather, it is determined by its consumerist environment of malls and museums, characterized by revivalist architecture. At the same time, the suburban shopping mall and a motorway network make nonsense of the idea of the city as a unique and well-defined space. These and other approaches encompass a wide spectrum of possibilities

  11. CYCLOSTRATIGRAPHY: A METHODOLOGICAL APPROACH

    Directory of Open Access Journals (Sweden)

    MARIO SPROVIERI

    2002-07-01

    Full Text Available Aim of this study is a synthetic description of the most used methodologies of cylostratigraphic analysis for the astronomical calibration of sedimentary sequences. The different numerical solutions of the insolation curve and, in particular, the most used astronomic curve La90 (1,1 are analyzed. Then, a detailed description of the methodologies for the astronomic calibration of different sedimentary sequences i on the basis of a litho-stratigraphic approach and ii on the basis of a spectral analysis applied to faunal and geochemical climate-sensitive records, is proposed. 

  12. Ethnographic Approaches in Primatology.

    Science.gov (United States)

    Dore, Kerry M; Radford, Lucy; Alexander, Sherrie; Waters, Siân

    2018-01-01

    The shared evolutionary histories and anatomical similarities between humans and non-human primates create dynamic interconnections between these alloprimates. In this foreword to Folia Primatologica's special issue on "Ethnographic Approaches in Primatology," we review the ethnographic method and existing literature at the intersection of primatology and ethnography. We summarize, compare and contrast the 5 contributions to this special issue to highlight why the human-non-human primate interface is a compelling area to investigate via ethnographic approaches and to encourage increased incorporation of ethnography into the discipline of primatology. Ethnography is a valuable and increasingly popular tool with its use no longer limited to anthropological practitioners investigating traditional, non-Western peoples. Scholars from many disciplines now use ethnographic methods to investigate all members of our globalised world, including non-humans. As our closest living relatives, non-human primates (hereafter "primates") are compelling subjects and thus appear in a range of contexts within ethnographic investigations. The goal of this special issue is to highlight the trajectory of research at the intersection of primatology and ethnography and to illustrate the importance of ethnographic methods for the advancement of primatology as a discipline. © 2018 S. Karger AG, Basel.

  13. Proteomic approach to nanotoxicity.

    Science.gov (United States)

    Matysiak, Magdalena; Kapka-Skrzypczak, Lucyna; Brzóska, Kamil; Gutleb, Arno C; Kruszewski, Marcin

    2016-03-30

    In recent years a large number of engineered nanomaterials (NMs) have been developed with promising technical benefits for consumers and medical appliances. In addition to already known potentially advantageous biological properties (antibiotic, antifungal and antiviral activity) of NMs, many new medical applications of NMs are foreseen, such as drug carriers, contrast agents, radiopharmaceuticals and many others. However, there is increasing concern about potential environmental and health effects due to NMs exposure. An increasing body of evidence suggests that NMs may trigger undesirable hazardous interactions with biological systems with potential to generate harmful effects. In this review we summarized a current state of knowledge on the proteomics approaches to nanotoxicity, including protein corona formation, in vitro and in vivo effects of exposure to NMs on proteome of different classes of organisms, from bacteria and plants to mammals. The effects of NMs on the proteome of environmentally relevant organisms are also described. Despite the benefit that development of nanotechnology may bring to the society, there are still major gaps of knowledge on the influence of nanomaterials on human health and the environment. Thus, it seems necessary to conduct further interdisciplinary research to fill the knowledge gaps in NM toxicity, using more holistic approaches than offered by conventional biological techniques. “OMICS” techniques will certainly help researchers in this field. In this paper we summarized the current stage of knowledge of the effects of nanoparticles on the proteome of different organisms, including those commonly used as an environmentally relevant indicator organisms.

  14. Technical approach document

    International Nuclear Information System (INIS)

    1988-04-01

    This document describes the general technical approaches and design criteria adopted by the US Department of Energy (DOE) in order to implement Remedial Action Plans (RAPs) and final designs that comply with EPS standards. This document is a revision to the original document. Major revisions were made to the sections in riprap selection and sizing, and ground-water; only minor revisions were made to the remainder of the document. The US Nuclear Regulatory Commission (NRC) has prepared a Standard Review Plan (NRC-SRP) which describes factors to be considered by the NRC in approving the RAP. Sections 3.0, 4.0, 5.0, and 7.0 of this document are arranged under the same headings as those used in the NRC-SRP. This approach is adopted in order to facilitate joint use of the documents. Section 2.0 (not included in the NRC-SRP) discusses design considerations; Section 3.0 describes surface-water hydrology and erosion control; Section 4.0 describes geotechnical aspects of pile design; Section 5.0 discusses the Alternate Site Selection Process; Section 6.0 deals with radiological issues (in particular, the design of the radon barrier); Section 7.0 discusses protection of groundwater resources; and Section 8.0 discusses site design criteria for the RAC

  15. Pharmacogenetics approach to therapeutics.

    Science.gov (United States)

    Koo, Seok Hwee; Lee, Edmund Jon Deoon

    2006-01-01

    1. Pharmacogenetics refers to the study of genetically controlled variations in drug response. Functional variants caused by single nucleotide polymorphisms (SNPs) in genes encoding drug-metabolising enzymes, transporters, ion channels and drug receptors have been known to be associated with interindividual and interethnic variation in drug response. Genetic variations in these genes play a role in influencing the efficacy and toxicity of medications. 2. Rapid, precise and cost-effective high-throughput technological platforms are essential for performing large-scale mutational analysis of genetic markers involved in the aetiology of variable responses to drug therapy. 3. The application of a pharmacogenetics approach to therapeutics in general clinical practice is still far from being achieved today owing to various constraints, such as limited accessibility of technology, inadequate knowledge, ambiguity of the role of variants and ethical concerns. 4. Drug actions are determined by the interplay of several genes encoding different proteins involved in various biochemical pathways. With rapidly emerging SNP discovery technological platforms and widespread knowledge on the role of SNPs in disease susceptibility and variability in drug response, the pharmacogenetics approach to therapeutics is anticipated to take off in the not-too-distant future. This will present profound clinical, economic and social implications for health care.

  16. Fournier's gangrene current approaches.

    Science.gov (United States)

    Ozkan, Omer F; Koksal, Neset; Altinli, Ediz; Celik, Atilla; Uzun, Mehmet A; Cıkman, Oztekin; Akbas, Alpaslan; Ergun, Ersin; Kiraz, Hasan A; Karaayvaz, Muammer

    2016-10-01

    Fournier's gangrene is a rare but highly mortal infectious disease characterised by fulminant necrotising fasciitis involving the genital and perineal regions. The objective of this study is to analyse the demographics, clinical feature and treatment approaches as well as outcomes of Fournier's gangrene. Data were collected retrospectively from medical records and operative notes. Patient data were analysed by demographics, aetiological factors, clinical features, treatment approaches and outcomes. Twelve patients (five female and seven male) were enrolled in this study. The most common aetiology was perianal abscess (41·6%). Wound cultures showed a mixture of microorganisms in six (50%) patients. For faecal diversion, while colostomy was performed in six cases (50%), Flexi-Seal was used in two cases (16·6%). In four patients (33·4%), no faecal diversion was performed. Negative pressure wound therapy (NPWT) system was effective in the last four patients (33·4%). The mean hospitalisation period in patients who used NPWT was 18 days, while it was 20 days in the others. NPWT in Fournier's gangrene is a safe dressing method. It promotes granulation formation. Flexi-Seal faecal management is an alternative method to colostomy and provides protection from its associated complications. The combination of two devices (Flexi-Seal and NPWT) is an effective and comfortable method in the management of Fournier's gangrene in appropriate patients. © 2014 The Authors. International Wound Journal © 2014 Medicalhelplines.com Inc and John Wiley & Sons Ltd.

  17. Breakfast: a multidisciplinary approach.

    Science.gov (United States)

    Affinita, Antonio; Catalani, Loredana; Cecchetto, Giovanna; De Lorenzo, Gianfranco; Dilillo, Dario; Donegani, Giorgio; Fransos, Lucia; Lucidi, Fabio; Mameli, Chiara; Manna, Elisa; Marconi, Paolo; Mele, Giuseppe; Minestroni, Laura; Montanari, Massimo; Morcellini, Mario; Rovera, Giuseppe; Rotilio, Giuseppe; Sachet, Marco; Zuccotti, Gian Vincenzo

    2013-07-10

    The role of breakfast as an essential part of an healthy diet has been only recently promoted even if breakfast practices were known since the Middle Age. The growing scientific evidences on this topic are extremely sector-based nevertheless breakfast could be regarded from different point of views and from different expertises. This approach, that take into account history, sociology, anthropology, medicine, psychology and pedagogy, is useful to better understand the value of this meal in our culture. The aim of this paper was to analyse breakfast-related issues based on a multidisciplinary approach with input by specialists from different fields of learning. Breakfast is now recommended as part of a diet because it is associated with healthier macro- and micronutrient intakes, body mass index and lifestyle. Moreover recent studies showed that breakfast improves cognitive function, intuitive perception and academic performance. Research demonstrates the importance of providing breakfast not only to children but in adults and elderly too. Although the important role breakfast plays in maintaining the health, epidemiological data from industrialised countries reveal that many individuals either eat a nutritionally unhealthy breakfast or skip it completely. The historical, bio-psychological and educational value of breakfast in our culture is extremely important and should be recognized and stressed by the scientific community. Efforts should be done to promote this practice for the individual health and well-being.

  18. Approaches for Stereo Matching

    Directory of Open Access Journals (Sweden)

    Takouhi Ozanian

    1995-04-01

    Full Text Available This review focuses on the last decade's development of the computational stereopsis for recovering three-dimensional information. The main components of the stereo analysis are exposed: image acquisition and camera modeling, feature selection, feature matching and disparity interpretation. A brief survey is given of the well known feature selection approaches and the estimation parameters for this selection are mentioned. The difficulties in identifying correspondent locations in the two images are explained. Methods as to how effectively to constrain the search for correct solution of the correspondence problem are discussed, as are strategies for the whole matching process. Reasons for the occurrence of matching errors are considered. Some recently proposed approaches, employing new ideas in the modeling of stereo matching in terms of energy minimization, are described. Acknowledging the importance of computation time for real-time applications, special attention is paid to parallelism as a way to achieve the required level of performance. The development of trinocular stereo analysis as an alternative to the conventional binocular one, is described. Finally a classification based on the test images for verification of the stereo matching algorithms, is supplied.

  19. Proteomics - new analytical approaches

    International Nuclear Information System (INIS)

    Hancock, W.S.

    2001-01-01

    Full text: Recent developments in the sequencing of the human genome have indicated that the number of coding gene sequences may be as few as 30,000. It is clear, however, that the complexity of the human species is dependent on the much greater diversity of the corresponding protein complement. Estimates of the diversity (discrete protein species) of the human proteome range from 200,000 to 300,000 at the lower end to 2,000,000 to 3,000,000 at the high end. In addition, proteomics (the study of the protein complement to the genome) has been subdivided into two main approaches. Global proteomics refers to a high throughput examination of the full protein set present in a cell under a given environmental condition. Focused proteomics refers to a more detailed study of a restricted set of proteins that are related to a specified biochemical pathway or subcellular structure. While many of the advances in proteomics will be based on the sequencing of the human genome, de novo characterization of protein microheterogeneity (glycosylation, phosphorylation and sulfation as well as the incorporation of lipid components) will be required in disease studies. To characterize these modifications it is necessary to digest the protein mixture with an enzyme to produce the corresponding mixture of peptides. In a process analogous to sequencing of the genome, shot-gun sequencing of the proteome is based on the characterization of the key fragments produced by such a digest. Thus, a glycopeptide and hence a specific glycosylation motif will be identified by a unique mass and then a diagnostic MS/MS spectrum. Mass spectrometry will be the preferred detector in these applications because of the unparalleled information content provided by one or more dimensions of mass measurement. In addition, highly efficient separation processes are an absolute requirement for advanced proteomic studies. For example, a combination of the orthogonal approaches, HPLC and HPCE, can be very powerful

  20. Slurry pipeline design approach

    Energy Technology Data Exchange (ETDEWEB)

    Betinol, Roy; Navarro R, Luis [Brass Chile S.A., Santiago (Chile)

    2009-12-19

    Compared to other engineering technologies, the design of a commercial long distance Slurry Pipeline design is a relatively new engineering concept which gained more recognition in the mid 1960 's. Slurry pipeline was first introduced to reduce cost in transporting coal to power generating units. Since then this technology has caught-up worldwide to transport other minerals such as limestone, copper, zinc and iron. In South America, the use of pipeline is commonly practiced in the transport of Copper (Chile, Peru and Argentina), Iron (Chile and Brazil), Zinc (Peru) and Bauxite (Brazil). As more mining operations expand and new mine facilities are opened, the design of the long distance slurry pipeline will continuously present a commercially viable option. The intent of this paper is to present the design process and discuss any new techniques and approach used today to ensure a better, safer and economical slurry pipeline. (author)

  1. Bioengineering a conceptual approach

    CERN Document Server

    Pavlovic, Mirjana

    2015-01-01

    This book explores critical principles and new concepts in bioengineering, integrating the biological, physical and chemical laws and principles that provide a foundation for the field. Both biological and engineering perspectives are included, with key topics such as the physical-chemical properties of cells, tissues and organs; principles of molecules; composition and interplay in physiological scenarios; and the complex physiological functions of heart, neuronal cells, muscle cells and tissues. Chapters evaluate the emerging fields of nanotechnology, drug delivery concepts, biomaterials, and regenerative therapy. The leading individuals and events are introduced along with their critical research. Bioengineering: A Conceptual Approach is a valuable resource for professionals or researchers interested in understanding the central elements of bioengineering. Advanced-level students in biomedical engineering and computer science will also find this book valuable as a secondary textbook or reference.

  2. Radiolab - three different approaches

    DEFF Research Database (Denmark)

    Lønstrup, Ansa

    2012-01-01

    object with a global audience, taken from one of the most popular podcasts worldwide, accessible on the internet. Finally, it is a piece of functional sound design, rather than a work of art, which raises the question of context more clearly. The result is three rather different approaches: 1) a process...... analysis, observing analytical listening strategies towards the constructed object, 2) a vocal analysis, regarding the sound object as a polyphony of voices, and 3) a contextual analysis, framing the sound object as a radio signature. Ola Stockfelt analyses the sound object as something that is constructed...... via his own repeated listening process – as a scholarly-analytical analysis of the subjectiv act of creating meaning. He draws on presumptions and prejudices, demonstrating the impossibility of a purely structural listening. The analysis relates these hermeneutical reflections to formal musicological...

  3. Editorial: Approaching 125.

    Science.gov (United States)

    Goodman, Sherryl

    2012-02-01

    With this issue, beginning Volume 121, the editorial team shifts from the strong leadership of David Watson to a team under my direction. Approaching 125 years of publication, the Journal of Abnormal Psychology has earned its place as the preeminent outlet for research in psychopathology. With gratitude to the newly assembled team of associate editors (AEs), consulting editors, and ad hoc reviewers, I look forward to guiding the journal through this next term. Nine well-respected scholars have agreed to serve as AEs: Timothy Brown, Laurie Chassin, Jeff Epstein, Jutta Joormann, Pamela Keel, Kate Keenan, Scott Lilienfeld, Angus MacDonald, and Michael Young. The new team is dedicated to working tirelessly to maintain and enhance the journal's esteemed tradition of excellence. Given the well-established strengths of the journal, I will not suggest any fundamental changes. PsycINFO Database Record (c) 2012 APA, all rights reserved.

  4. Integration a functional approach

    CERN Document Server

    Bichteler, Klaus

    1998-01-01

    This book covers Lebesgue integration and its generalizations from Daniell's point of view, modified by the use of seminorms. Integrating functions rather than measuring sets is posited as the main purpose of measure theory. From this point of view Lebesgue's integral can be had as a rather straightforward, even simplistic, extension of Riemann's integral; and its aims, definitions, and procedures can be motivated at an elementary level. The notion of measurability, for example, is suggested by Littlewood's observations rather than being conveyed authoritatively through definitions of (sigma)-algebras and good-cut-conditions, the latter of which are hard to justify and thus appear mysterious, even nettlesome, to the beginner. The approach taken provides the additional benefit of cutting the labor in half. The use of seminorms, ubiquitous in modern analysis, speeds things up even further. The book is intended for the reader who has some experience with proofs, a beginning graduate student for example. It might...

  5. The Tripod Approach

    DEFF Research Database (Denmark)

    Bang, Anne Louise

    2012-01-01

    -and-break decision for a company. However textile design research has shown that experience of emotional value is closely connected to fabric perception, and much literature suggests that textiles are experienced by a combination of sensory evaluation and memory associations. This paper introduces the Tripod......The term ‘next to my skin’ is frequently used as a way to describe the close bonds between human beings and textiles. It is also widely accepted within the broad field of textile professionals that textile attributes related to emotional value – for example hand, look and drape – can be a make...... Approach as a framework that can support designing the stimuli, which can lead to personal experiences of emotional value in relation to applied textiles. It can be used to access the relevant level of entry in the textile design process focusing on appropriate design parameters, and support designing...

  6. Neuroblastoma: A neurochemical approach

    International Nuclear Information System (INIS)

    Schor, N.F.

    1991-01-01

    Neuroblastoma is among the most common malignancies of childhood. Despite greatly improved therapy for some pediatric tumors, the prognosis for children with metastatic neuroblastoma has not changed significantly in the past 10 years. With conventional chemotherapy, radiation therapy, and surgery, children with metastatic neuroblastoma have a 20% long-term survival rate. The authors describe here approaches to neuroblastoma that target its neuronal characteristics. On the one hand, the neurotransmitter receptors on the surface of the neuroblastoma cells and, on the other hand, specific isozymes that distinguish neuroblastoma cells from their normal counterparts are the focus of these experimental therapies. In the former case, specificity for tumor cells is effected by (1) selective protection of normal neuronal elements from toxicity, or (2) selective potentiation of toxicity for neural tumor cells. It is hoped that these strategies will be generalizable to other neural crest-derived tumors. 32 references

  7. How to approach thrombocytopenia.

    Science.gov (United States)

    Stasi, Roberto

    2012-01-01

    Thrombocytopenia is a common hematologic finding with variable clinical expression. A low platelet count may be the initial manifestation of infections such as HIV and hepatitis C virus or it may reflect the activity of life-threatening disorders such as the thrombotic microangiopathies. A correct identification of the causes of thrombocytopenia is crucial for the appropriate management of these patients. In this review, we present a systematic evaluation of adults with thrombocytopenia. The approach is clearly different between outpatients, who are frequently asymptomatic and in whom we can sometimes indulge in sophisticated and relatively lengthy investigations, and the dramatic presentation of acute thrombocytopenia in the emergency department or in the intensive care unit, which requires immediate intervention and for which only a few diagnostic tests are available. A brief discussion of the most common etiologies seen in both settings is provided.

  8. Investigational approaches for mesothelioma

    Directory of Open Access Journals (Sweden)

    Veerle F Surmont

    2011-08-01

    Full Text Available MPM is a rare, aggressive tumour with a poor prognosis. In view of the poor survival benefit from first-line chemotherapy and the lack of subsequent effective treatment options, there is a strong need for the development of more effective treatment approaches for patients with MPM. This review will provide a comprehensive state of the art of new investigational approaches for mesothelioma. In an introductory section, the aetiology, epidemiology, natural history and standard of care treatment for MPM will be discussed. This review provide an update of the major clinical trials that impact mesothelioma treatment, discuss the impact of novel therapeutics and provide perspective on where the clinical research in mesothelioma is moving.The evidence was collected by a systematic analysis of the literature (2000–2011 using the databases Medline (National Library of Medicine, USA, Embase (Elsevier, Netherlands, Cochrane Library (Great Britain, National Guideline Clearinghouse (USA, HTA Database (International Network of Agencies for Health Technology Assessment – INAHTA, NIH database (USA, International Pleural Mesothelioma Program – WHOLIS (WHO Database , with the following keywords and filters: mesothelioma, guidelines, treatment, surgery, chemotherapy, radiotherapy, review, investigational, drugsCurrently different targeted therapies and biologicals are under investigation for MPM. It is important that the molecular biologic research should first focus on mesothelioma-specific pathways and biomarkers in order to have more effective treatment options for this disease. The use of array technology will be certainly an implicit gain in the identification of new potential prognostic or biomarkers or important pathways in the MPM pathogenesis. Probably a central mesothelioma virtual tissue bank may contribute to the ultimate goal to identify druggable targets and to develop personalized treatment for the MPM patients.

  9. Investigational Approaches for Mesothelioma

    International Nuclear Information System (INIS)

    Surmont, Veerle F.; Thiel, Eric R. E. van; Vermaelen, Karim; Meerbeeck, Jan P. van

    2011-01-01

    Malignant pleural mesothelioma (MPM) is a rare, aggressive tumor with a poor prognosis. In view of the poor survival benefit from first-line chemotherapy and the lack of subsequent effective treatment options, there is a strong need for the development of more effective treatment approaches for patients with MPM. This review will provide a comprehensive state of the art of new investigational approaches for mesothelioma. In an introductory section, the etiology, epidemiology, natural history, and standard of care treatment for MPM will be discussed. This review provide an update of the major clinical trials that impact mesothelioma treatment, discuss the impact of novel therapeutics, and provide perspective on where the clinical research in mesothelioma is moving. The evidence was collected by a systematic analysis of the literature (2000–2011) using the databases Medline (National Library of Medicine, USA), Embase (Elsevier, Netherlands), Cochrane Library (Great Britain), National Guideline Clearinghouse (USA), HTA Database (International Network of Agencies for Health Technology Assessment – INAHTA), NIH database (USA), International Pleural Mesothelioma Program – WHOLIS (WHO Database), with the following keywords and filters: mesothelioma, guidelines, treatment, surgery, chemotherapy, radiotherapy, review, investigational, drugs. Currently different targeted therapies and biologicals are under investigation for MPM. It is important that the molecular biologic research should first focus on mesothelioma-specific pathways and biomarkers in order to have more effective treatment options for this disease. The use of array technology will be certainly an implicit gain in the identification of new potential prognostic or biomarkers or important pathways in the MPM pathogenesis. Probably a central mesothelioma virtual tissue bank may contribute to the ultimate goal to identify druggable targets and to develop personalized treatment for the MPM patients.

  10. Standard Approaches to the Acetabulum Part 2: Ilioinguinal Approach.

    Science.gov (United States)

    Gänsslen, A; Grechenig, S T; Nerlich, M; Müller, M; Grechenig, W

    2016-01-01

    The ilioinguinal approach is one of the standard approaches in the treatment of displaced acetabular fractures used during the last decades (9). The meta-analysis of Giannoudis et al. showed that 21.9% of acetabular fractures were historically treated using this approach (3). One of the disadvantages of this study was, that studies focussing especially on posterior wall stabilization and studies dealing with more complex fracture types treated by extended approaches were integrated. Thus, these fracture types were overrepresented. Re-analysis excluding these data lead to an increase of the rate of anterior approaches to 25.9%. More recent data (years 2005-2007) from the German multicenter study showed that presently in almost 45% of the cases the single ilioinguinal approach was used and only 38% of patients were stabilized via the KocherLangenbeck approach (11). Historically, the Smith-Peterson approach (15, 17) and the iliofemoral approach were used to treat acetabular fractures. In the 60ies, based on the work by Letournel and Judet, the ilioinguinal approach was developed for acetabular fracture fixation (9). It is an extrapelvic approach resulting in an indirect reconstruction concept of the acetabulum without direct visualization of the articular acetabulum. The ilioinguinal approach was the standard anterior approach during the last 30-40 years. An important advantage is the reduced soft tissue detachment of periarticular muscles with only a small risk of developing heterotopic bone formation. The aim of the second part of "Standard approaches to the acetabulum" is to report on the special topics indication, positioning, exposure, incision, dissection, the anatomical basis of osteosynthesis and present results using ilioinguinal approach.

  11. Approach to lower back pain

    African Journals Online (AJOL)

    an approach to this common symptom and how to distinguish the benign, mechanical type of back pain from the more sinister, but less frequently encountered ... Approach to management. Therapy or management of chronic LBP involves a multidisciplinary approach. The aim is to prevent a chronic vicious cycle by means of ...

  12. Structural Sustainability - Heuristic Approach

    Science.gov (United States)

    Rostański, Krzysztof

    2017-10-01

    Nowadays, we are faced with a challenge of having to join building structures with elements of nature, which seems to be the paradigm of modern planning and design. The questions arise, however, with reference to the following categories: the leading idea, the relation between elements of nature and buildings, the features of a structure combining such elements and, finally, our perception of this structure. If we consider both the overwhelming globalization and our attempts to preserve local values, the only reasonable solution is to develop naturalistic greenery. It can add its uniqueness to any building and to any developed area. Our holistic model, presented in this paper, contains the above mentioned categories within the scope of naturalism. The model is divided into principles, actions related, and possible effects to be obtained. It provides a useful tool for determining the ways and priorities of our design. Although it is not possible to consider all possible actions and solutions in order to support sustainability in any particular design, we can choose, however, a proper mode for our design according to the local conditions by turning to the heuristic method, which helps to choose priorities and targets. Our approach is an attempt to follow the ways of nature as in the natural environment it is optimal solutions that appear and survive, idealism being the domain of mankind only. We try to describe various natural processes in a manner comprehensible to us, which is always a generalization. Such definitions, however, called artificial by naturalists, are presented as art or the current state of knowledge by artists and engineers. Reality, in fact, is always more complicated than its definitions. The heuristic method demonstrates the way how to optimize our design. It requires that all possible information about the local environment should be gathered, as the more is known, the fewer mistakes are made. Following the unquestionable principles, we can

  13. Approach to team skills training

    International Nuclear Information System (INIS)

    Koontz, J.L.; Roe, M.L.; Gaddy, C.D.

    1987-01-01

    The US commercial nuclear power industry has recognized the importance of team skills in control room operation. The desire to combine training of team interaction skills, like communications, with technical knowledge of reactor operations requires a unique approach to training. An NRC-sponsored study identified a five-phase approach to team skills training designed to be consistent with the systems approach to training currently endorsed by the NRC Policy Statement on Training and Qualification. This paper describes an approach to team skills training with emphasis on the nuclear power plant control room crew. An approach to team skills training

  14. APPROACHES TO PUBLIC INTEGRITY

    Directory of Open Access Journals (Sweden)

    Simona-Roxana ULMAN

    2015-08-01

    Full Text Available Both concepts, integrity and public integrity, are always asked qualities in the social and economic environment, but they are never well defined. In this context, finding precise definitions and offering an ample explanation of the concepts are desired and useful for both economic theoretical and practical levels and become the aim of the present paper. Without a good understanding of a concept, no one is capable to attain it. In this context, it is impossible to ask for a public sector of integrity if both public actors and the citizens do not know what it really means. Therefore, the public actors first have to understand what integrity really supposes, and, then, to be capable to respect its principles. Taking into consideration the effects of public integrity or, on its opposite, of the divergence from it, especially represented by the phenomenon of corruption, on the economy at the macro, but also, on the micro level, public integrity in itself becomes a real economic problem that is aimed to be extensively analyzed through our interdisciplinary approach.

  15. Modeling prosody: Different approaches

    Science.gov (United States)

    Carmichael, Lesley M.

    2002-11-01

    Prosody pervades all aspects of a speech signal, both in terms of raw acoustic outcomes and linguistically meaningful units, from the phoneme to the discourse unit. It is carried in the suprasegmental features of fundamental frequency, loudness, and duration. Several models have been developed to account for the way prosody organizes speech, and they vary widely in terms of their theoretical assumptions, organizational primitives, actual procedures of application to speech, and intended use (e.g., to generate speech from text vs. to model the prosodic phonology of a language). In many cases, these models overtly contradict one another with regard to their fundamental premises or their identification of the perceptible objects of linguistic prosody. These competing models are directly compared. Each model is applied to the same speech samples. This parallel analysis allows for a critical inspection of each model and its efficacy in assessing the suprasegmental behavior of the speech. The analyses illustrate how different approaches are better equipped to account for different aspects of prosody. Viewing the models and their successes from an objective perspective allows for creative possibilities in terms of combining strengths from models which might otherwise be considered fundamentally incompatible.

  16. Light cone approach

    International Nuclear Information System (INIS)

    Brodsky, Stan

    1993-01-01

    One of the most challenging problems in theoretical high energy physics is to compute the bound state structure of the proton and other hadrons from quantum chromodynamics (QCD), the field theory of quarks and gluons. The goal is not only to calculate the spectrum of hadrons masses from first principles, but also to derive the momentum and spin distributions of the quarks and gluons which control high energy hadron interactions. One approach to these difficult calculations is to simulate QCD on an artificial lattice. Recently, several new methods based on ''light-cone'' quantization have been proposed as alternatives to lattice theory for solving non-perturbative problems in QCD and other field theories. The basic idea is a generalization of Heisenberg's pioneer matrix formulation of quantum mechanics: if one could numerically diagonalize the matrix of the Hamiltonian representing the underlying QCD interaction, then the resulting eigenvalues would give the hadron spectrum, while the corresponding eigenstates would describe each hadron in terms of its quark and gluon degrees of freedom

  17. Developing regulatory approaches

    International Nuclear Information System (INIS)

    Axelsson, Lars

    2012-01-01

    Lars Axelsson presented SSM progress on oversight of LMfS/SC since the Chester 1 Workshop in 2007. Current SSM approaches for safety culture oversight include targeted safety management and safety culture inspections, compliance inspections which cover aspects of safety management/safety culture and multi-disciplinary team inspections. Examples of themes for targeted inspections include management of ambiguous operational situations or other weak signals, understanding of and attitudes to Human Performance tools, the Safety Department's role and authority and Leadership for safety. All regulatory activities provide inputs for the SSM yearly safety evaluation of each licensee. A form has been developed to capture safety culture observations from inspections and other interactions with licensees. Analysis will be performed to identify patterns and provide information to support planning of specific Safety Culture activities. Training has been developed for regulatory staff to enhance the quality of regulatory interventions on safety culture. This includes a half-day seminar to provide an overview of safety culture, and a workshop which provides more in-depth discussion on cultural issues and how to capture those during regulatory activities. Future plans include guidance for inspectors, and informal seminars on safety culture with licensees

  18. Approaches to adenomyomectomy

    Directory of Open Access Journals (Sweden)

    Serene Thain

    2015-08-01

    Full Text Available Adenomyosis is a common gynecological condition that affects women, causing menstrual disturbances, pain, and subfertility. Adenomyomectomy as an alternative to hysterectomy has been widely performed in those who have not completed childbearing or those refusing a hysterectomy for a variety of reasons. Whichever the surgical route, the challenges of adenomyomectomy include possible misdiagnosis, defining the extent of resection, technical difficulties, dealing with the associated complications, and managing the risks of uterine rupture during a subsequent pregnancy. The principles of surgery mimic those of myomectomy, but the evolution of adenomyomectomy has been relatively unexciting with a general paucity of published data to date. Laparoscopic techniques have proven feasible generally, avoiding the risks of open surgery while conferring the benefits of microsurgery. Limitations in tactile feedback and access constraints have been the main drawbacks via this route. Meticulous stitching and repair is still of paramount importance in these operations. Preoperative gonadotropin-releasing hormone agonists have proven effective in shrinking the disease and reducing blood loss during surgery, whereas the postoperative use has resulted in a dramatic reduction in symptoms. Uterine artery ligation techniques have also been shown to be useful adjuncts, although we still need to be mindful of the potential effects in those desiring fertility. Furthermore, there is still no foolproof way in predicting those at risk of uterine rupture after adenomyomectomy. Hence, a nonprescriptive approach in managing adenomyomas is advised, where proper patient selection and counseling are important.

  19. Syncope: Approach to diagnosis

    Directory of Open Access Journals (Sweden)

    Om Murti Anil

    2016-01-01

    Full Text Available Syncope is a transient loss of consciousness (LOC due to transient global cerebral hypoperfusion characterized by rapid onset, short duration, and spontaneous complete recovery. Here, the term "transient LOC" encompasses all disorders characterized by self-limited LOC irrespective of the mechanism. Central point in pathophysiology of the development of syncope is fall in systemic blood pressure (BP with a decrease in global cerebral blood flow. The evaluation and treatment of syncope are very challenging because syncope is not the only cause of transient LOC. Moreover, symptoms of syncope are fleeting, patient is usually asymptomatic at the time of evaluation, and most of the events are often unwitnessed. The guiding principle of assessment is to differentiate syncope from other causes of transient LOC and the more benign causes of syncope from the potentially serious ones. Initial assessment of syncope consists of a detailed history and examination complemented by 12-lead electrocardiography and supine and standing BP. If the cause is suspected, then further investigations may be needed to confirm the particular disorder. A deliberate approach based on initial risk stratification is more likely to give a correct diagnosis. Despite the difficulties, a thorough evaluation of the cause of syncope is warranted in all patients, not just in those deemed to be at high mortality risk. The goal in every case should be to determine the cause with sufficient confidence to provide a reliable assessment of prognosis and treatment options.

  20. Syncope: therapeutic approaches.

    Science.gov (United States)

    Benditt, David G; Nguyen, John T

    2009-05-12

    Syncope is a common clinical problem characterized by transient, spontaneously self-terminating loss of consciousness with complete and prompt recovery; the cause is insufficiency of cerebral oxygen/nutrient supply most often due to a transient fall of systemic arterial pressure to levels below those tolerated by cerebrovascular autoregulation. Careful and thorough evaluation of the cause of syncope is warranted in all patients. Determining that certain individuals are at "low mortality risk" is inadequate; syncope, although often benign from a mortality perspective, tends to recur, is associated with risk of physical injury, diminishes quality-of-life, and might lead to restriction from employment or avocation. However, the diagnostic evaluation and treatment of syncope is challenging for many reasons. First, syncope is only 1 of many causes of transient loss of consciousness. Second, the patient's symptoms are fleeting, and the patient is generally fully recovered when seen in the clinic; only infrequently are there helpful physical findings. Third, spontaneous events are often unwitnessed by medical professionals; consequently, the medical history of symptom events is usually a "second-hand" or "third-hand" story. Finally, there is often an excessive sense of diagnostic "urgency" that tends to result in a rush to undertake multiple poorly considered "diagnostic" testing procedures; a deliberate approach based on initial risk stratification is more likely to reap the dual rewards of a correct diagnosis and initiation of effective treatment in a cost-effective manner.

  1. Approaches to refractory epilepsy

    Directory of Open Access Journals (Sweden)

    Jerome Engel

    2014-01-01

    Full Text Available Epilepsy is one of the most common serious neurological conditions, and 30 to 40% of people with epilepsy have seizures that are not controlled by medication. Patients are considered to have refractory epilepsy if disabling seizures continue despite appropriate trials of two antiseizure drugs, either alone or in combination. At this point, patients should be referred to multidisciplinary epilepsy centers that perform specialized diagnostic testing to first determine whether they are, in fact, pharmacoresistant, and then, if so, offer alternative treatments. Apparent pharmacoresistance can result from a variety of situations, including noncompliance, seizures that are not epileptic, misdiagnosis of the seizure type or epilepsy syndrome, inappropriate use of medication, and lifestyle issues. For patients who are pharmacoresistant, surgical treatment offers the best opportunity for complete freedom from seizures. Surgically remediable epilepsy syndromes have been identified, but patients with more complicated epilepsy can also benefit from surgical treatment and require more specialized evaluation, including intracranial EEG monitoring. For patients who are not surgical candidates, or who are unwilling to consider surgery, a variety of other alternative treatments can be considered, including peripheral or central neurostimulation, ketogenic diet, and complementary and alternative approaches. When such alternative treatments are not appropriate or effective, quality of life can still be greatly improved by the psychological and social support services offered by multidisciplinary epilepsy centers. A major obstacle remains the fact that only a small proportion of patients with refractory epilepsy are referred for expert evaluation and treatment.

  2. Material Modelling - Composite Approach

    DEFF Research Database (Denmark)

    Nielsen, Lauge Fuglsang

    1997-01-01

    This report is part of a research project on "Control of Early Age Cracking" - which, in turn, is part of the major research programme, "High Performance Concrete - The Contractor's Technology (HETEK)", coordinated by the Danish Road Directorate, Copenhagen, Denmark, 1997.A composite-rheological ......This report is part of a research project on "Control of Early Age Cracking" - which, in turn, is part of the major research programme, "High Performance Concrete - The Contractor's Technology (HETEK)", coordinated by the Danish Road Directorate, Copenhagen, Denmark, 1997.A composite......-rheological model of concrete is presented by which consistent predictions of creep, relaxation, and internal stresses can be made from known concrete composition, age at loading, and climatic conditions. No other existing "creep prediction method" offers these possibilities in one approach.The model...... in this report is that cement paste and concrete behave practically as linear-viscoelastic materials from an age of approximately 10 hours. This is a significant age extension relative to earlier studies in the literature where linear-viscoelastic behavior is only demonstrated from ages of a few days. Thus...

  3. The narrative approach to personalisation

    Science.gov (United States)

    Conlan, Owen; Staikopoulos, Athanasios; Hampson, Cormac; Lawless, Séamus; O'keeffe, Ian

    2013-06-01

    This article describes the narrative approach to personalisation. This novel approach to the generation of personalised adaptive hypermedia experiences employs runtime reconciliation between a personalisation strategy and a number of contextual models (e.g. user and domain). The approach also advocates the late binding of suitable content and services to the generated personalised pathway resulting in an interactive composition that comprises services as well as content. This article provides a detailed definition of the narrative approach to personalisation and showcases the approach through the examination of two use-cases: the personalised digital educational games developed by the ELEKTRA and 80Days projects; and the personalised learning activities realised as part of the AMAS project. These use-cases highlight the general applicability of the narrative approach and how it has been applied to create a diverse range of real-world systems.

  4. Field theory approach to gravitation

    International Nuclear Information System (INIS)

    Yilmaz, H.

    1978-01-01

    A number of authors considered the possibility of formulating a field-theory approach to gravitation with the claim that such an approach would uniquely lead to Einstein's theory of general relativity. In this article it is shown that the field theory approach is more generally applicable and uniqueness cannot be claimed. Theoretical and experimental reasons are given showing that the Einsteinian limit appears to be unviable

  5. New Approaches to Final Cooling

    Energy Technology Data Exchange (ETDEWEB)

    Neuffer, David [Fermilab

    2014-11-10

    A high-energy muon collider scenario require a “final cooling” system that reduces transverse emittances by a factor of ~10 while allowing longitudinal emittance increase. The baseline approach has low-energy transverse cooling within high-field solenoids, with strong longitudinal heating. This approach and its recent simulation are discussed. Alternative approaches which more explicitly include emittance exchange are also presented. Round-to-flat beam transform, transverse slicing, and longitudinal bunch coalescence are possible components of the alternative approach. A more explicit understanding of solenoidal cooling beam dynamics is introduced.

  6. Student Approaches to Achieving Understanding--Approaches to Learning Revisited

    Science.gov (United States)

    Fyrenius, Anna; Wirell, Staffan; Silen, Charlotte

    2007-01-01

    This article presents a phenomenographic study that investigates students' approaches to achieving understanding. The results are based on interviews, addressing physiological phenomena, with 16 medical students in a problem-based curriculum. Four approaches--sifting, building, holding and moving--are outlined. The holding and moving approaches…

  7. Significance of surgical management for cystic prolactinoma.

    Science.gov (United States)

    Ogiwara, Toshihiro; Horiuchi, Tetsuyoshi; Nagm, Alhusain; Goto, Tetsuya; Hongo, Kazuhiro

    2017-04-01

    It is generally accepted that dopamine agonists (DA) represent the first-line treatment for most patients with prolactinoma, and patients become candidates for surgical intervention when DA is contraindicated. Surgical indication for cystic prolactinoma remains controversial. This study was performed to investigate the significance of surgery for cystic prolactinoma. A total of 28 patients that underwent transsphenoidal resection of prolactinoma between February 2004 and May 2016 were reviewed. Five consecutive patients with cystic prolactinoma were included in this study. Our surgical strategy for cystic prolactinoma was categorized as follows: first, when the purpose of surgical resection was normalization of the prolactin level, aggressive resection was performed; second, when volume reduction was essential to relieve the visual symptoms and headache, internal decompression was performed followed by DA therapy. The clinical outcomes were analyzed accordingly. All cystic prolactinoma were resected via the transsphenoidal approach without any complications, and all symptoms including visual impairment and hypogonadal activity were finally relieved combined with medication. Surgery for cystic prolactinoma could be a better option. Transsphenoidal surgery is relatively safe to remove the cystic prolactinoma, additionally it can normalize the prolactine level and achieve adequate and rapid decompression of optic chiasm. The risk of transsphenoidal surgery is highly dependent on the skill of the surgeon and treatment decision for cystic prolactinoma needs to be individualized for each patient.

  8. Mitochondrial biogenesis: pharmacological approaches.

    Science.gov (United States)

    Valero, Teresa

    2014-01-01

    Organelle biogenesis is concomitant to organelle inheritance during cell division. It is necessary that organelles double their size and divide to give rise to two identical daughter cells. Mitochondrial biogenesis occurs by growth and division of pre-existing organelles and is temporally coordinated with cell cycle events [1]. However, mitochondrial biogenesis is not only produced in association with cell division. It can be produced in response to an oxidative stimulus, to an increase in the energy requirements of the cells, to exercise training, to electrical stimulation, to hormones, during development, in certain mitochondrial diseases, etc. [2]. Mitochondrial biogenesis is therefore defined as the process via which cells increase their individual mitochondrial mass [3]. Recent discoveries have raised attention to mitochondrial biogenesis as a potential target to treat diseases which up to date do not have an efficient cure. Mitochondria, as the major ROS producer and the major antioxidant producer exert a crucial role within the cell mediating processes such as apoptosis, detoxification, Ca2+ buffering, etc. This pivotal role makes mitochondria a potential target to treat a great variety of diseases. Mitochondrial biogenesis can be pharmacologically manipulated. This issue tries to cover a number of approaches to treat several diseases through triggering mitochondrial biogenesis. It contains recent discoveries in this novel field, focusing on advanced mitochondrial therapies to chronic and degenerative diseases, mitochondrial diseases, lifespan extension, mitohormesis, intracellular signaling, new pharmacological targets and natural therapies. It contributes to the field by covering and gathering the scarcely reported pharmacological approaches in the novel and promising field of mitochondrial biogenesis. There are several diseases that have a mitochondrial origin such as chronic progressive external ophthalmoplegia (CPEO) and the Kearns- Sayre syndrome (KSS

  9. Cognitive Approaches to Automated Instruction.

    Science.gov (United States)

    Regian, J. Wesley, Ed.; Shute, Valerie J., Ed.

    This book contains a snapshot of state-of-the-art research on the design of automated instructional systems. Selected cognitive psychologists were asked to describe their approach to instruction and cognitive diagnosis, the theoretical basis of the approach, its utility and applicability, and the knowledge engineering or task analysis methods…

  10. Current approaches to norms research

    Science.gov (United States)

    John L. Heywood

    2000-01-01

    The dialogue session was a continuation of a debate about norms and the application of normative standards to wilderness management that has taken place throughout the 1990s at national meetings and in the research literature. Researchers who have made significant contributions to the normative approach to wilderness recreation management presented three approaches to...

  11. Workplace English: Approach and Analysis.

    Science.gov (United States)

    Prince, David

    1984-01-01

    Describes two approaches to teaching vocational English as a second language: (1) describing work activities in terms of processes and procedures and (2) describing work activities in terms of specific human behaviors. Suggests a goal analysis as an initial step before deciding which approach to take in any training project. (SED)

  12. Extending cosmology: the metric approach

    OpenAIRE

    Mendoza, S.

    2012-01-01

    Comment: 2012, Extending Cosmology: The Metric Approach, Open Questions in Cosmology; Review article for an Intech "Open questions in cosmology" book chapter (19 pages, 3 figures). Available from: http://www.intechopen.com/books/open-questions-in-cosmology/extending-cosmology-the-metric-approach

  13. An approach to the future

    Science.gov (United States)

    Peter C. Bishop

    2012-01-01

    This paper describes the rudiments of an approach to the future that we should teach and practice in our personal and professional lives. It begins with a consideration of change. The future is about change. If there were no change, we would have no reason to pay attention to the future. The paper concludes with an approach to long-term forecasting that takes...

  14. An Experimental Approach To… Everything!

    Science.gov (United States)

    Orr, Taylor; Flowers, Jim

    2014-01-01

    The goal of formal education is student learning. By emphasizing experimentation in the classroom or lab, students learn about the results of a particular inquiry. But more importantly, they learn to refine their approach to learning by creating new knowledge rather than merely remembering what they have been told. An inquiry approach where…

  15. Artificial intelligence approaches in statistics

    International Nuclear Information System (INIS)

    Phelps, R.I.; Musgrove, P.B.

    1986-01-01

    The role of pattern recognition and knowledge representation methods from Artificial Intelligence within statistics is considered. Two areas of potential use are identified and one, data exploration, is used to illustrate the possibilities. A method is presented to identify and separate overlapping groups within cluster analysis, using an AI approach. The potential of such ''intelligent'' approaches is stressed

  16. Probabilistic approach to pattern selection

    Science.gov (United States)

    Yukalov, V. I.

    2001-03-01

    The problem of pattern selection arises when the evolution equations have many solutions, whereas observed patterns constitute a much more restricted set. An approach is advanced for treating the problem of pattern selection by defining the probability distribution of patterns. Then the most probable pattern naturally corresponds to the largest probability weight. This approach provides the ordering principle for the multiplicity of solutions explaining why some of them are more preferable than others. The approach is applied to solving the problem of turbulent photon filamentation in resonant media.

  17. A Biosemiotic Approach to Health

    DEFF Research Database (Denmark)

    Hoffmeyer, Jesper

    2010-01-01

    approaches are invaluable. The aim is to find a common platform that serves in treating human persons as undivided wholes. Since semiosis (viz. the meaningful interpretation of cues, signals, events or states) is vital to communication at both levels, the resulting sign-process is a viable choice......By replacing the traditional chemical approach to the understanding of body function by a sign-theoretic or semiotic approach, biosemiotics enters a no-man’s-land between biological and social domains of human life. The aim is not to subsume the social under the biological or vice versa; both...

  18. Vanpooling: the three major approaches

    Energy Technology Data Exchange (ETDEWEB)

    Sears, P.M.

    1979-08-01

    The manual provides technical assistance to existing or prospective vanpool sponsors. It is designed to help them promote vanpooling in its three major approaches: employer sponsored, third party sponsored, and driver owned and operated. The first chapter is an overview of vanpooling and a second chapter, on vanpool marketing, is addressed to ridesharing coordinators and others whose responsibilities include the promotion of vanpooling. Some fact sheets on the three approaches provide convenient summaries of the needs and opportunities of each approach and suggest solutions to practical problems likely to be encountered in starting new vanpool programs.

  19. Approaches to Scandinavian Crime Fiction

    DEFF Research Database (Denmark)

    Agger, Gunhild

    2010-01-01

    as the approach of genre typology and the concept of evil – seemingly disparate concepts and approaches, but all related to the complex processes in the borderlands between crime fiction and society. Using examples from Scandinavian crime fiction, I discuss whether the growing proximity to international genres......The working paper discusses some of the major approaches to Scandinavian crime fiction in the light of the dominant features of crime culture, e.g. the broad exposure of crime fiction via different platforms and media. In this connection, the concept of mediatization is considered as well......, ways of production and standards increasingly removes Scandinavian crime fiction from its original attractions or not....

  20. Approaches to ultrafast neutron detectors

    International Nuclear Information System (INIS)

    Wang, C.L.; Kalibjian, R.; Singh, M.S.

    1984-01-01

    We discuss two approaches to obtain detectors of very high temporal resolution. In the first approach, uranium-coated cathode is used in a streak tube configuration. Secondary electrons accompanying the fission fragments from a neutron-uranium reaction are accelerated, focussed and energy analyzed through a pinhole and streaked. Calculations show that 20 ps time-resolution can be obtained. In the second approach, a uranium-coated cathode is integrated into a transmission line. State-of-the-art technology indicates that time resolution of 20 ps can be obtained by gating the cathode with a fast electric pulse

  1. On the quantum CTRW approach

    Science.gov (United States)

    Cáceres, Manuel O.

    2017-04-01

    The concept of continuous-time random walk is generalized into the quantum approach using a completely positive map. This approach introduces in a phenomenological way the concept of disorder in the transport problem of a quantum open system. If the waiting-time of the continuous-time renewal approach is exponential we recover a semigroup for a dissipative quantum walk. Two models of non-Markovian evolution have been solved considering different types of waiting-time functions. Contribution to the Topical Issue "Continuous Time Random Walk Still Trendy: Fifty-year History, Current State and Outlook", edited by Ryszard Kutner and Jaume Masoliver.

  2. Approaches to Teaching Organizational Communication.

    Science.gov (United States)

    Applebaum, Ronald L.

    1998-01-01

    Discusses fundamental problems in selecting an approach to organizational communications; the purpose of an organizational communication course; the structure and content of organizational communication coursework; and teaching strategies used in the basic course in organizational communication. (RS)

  3. Abstract Cauchy problems three approaches

    CERN Document Server

    Melnikova, Irina V

    2001-01-01

    Although the theory of well-posed Cauchy problems is reasonably understood, ill-posed problems-involved in a numerous mathematical models in physics, engineering, and finance- can be approached in a variety of ways. Historically, there have been three major strategies for dealing with such problems: semigroup, abstract distribution, and regularization methods. Semigroup and distribution methods restore well-posedness, in a modern weak sense. Regularization methods provide approximate solutions to ill-posed problems. Although these approaches were extensively developed over the last decades by many researchers, nowhere could one find a comprehensive treatment of all three approaches.Abstract Cauchy Problems: Three Approaches provides an innovative, self-contained account of these methods and, furthermore, demonstrates and studies some of the profound connections between them. The authors discuss the application of different methods not only to the Cauchy problem that is not well-posed in the classical sense, b...

  4. Some Current Approaches to Interoperability

    National Research Council Canada - National Science Library

    Carney, David; Fisher, David; Morris, Ed; Place, Pat

    2005-01-01

    .... These efforts include work in ontologies, service-oriented architectures, emergent methods, and new approaches to security. While these efforts show many signs of promise, a considerable amount of work will be needed to bring these to a mature state.

  5. Systems Approach to Urban Operations

    National Research Council Canada - National Science Library

    Sutherland, David W

    2003-01-01

    .... The battles of Aachen, Stalingrad, and Grozny (2000), reflect this rubble approach. However, several factors have driven military thinkers to look for a more efficient and effective manner to defeat an adversary within an urban environment...

  6. Anterior approach for knee arthrography

    International Nuclear Information System (INIS)

    Zurlo, J.V.; Towers, J.D.; Golla, S.

    2001-01-01

    Objective. To develop a new method of magnetic resonance arthrography (MRA) of the knee using an anterior approach analogous to the portals used for knee arthroscopy.Design. An anterior approach to the knee joint was devised mimicking anterior portals used for knee arthroscopy. Seven patients scheduled for routine knee MRA were placed in a decubitus position and under fluoroscopic guidance a needle was advanced from a position adjacent to the patellar tendon into the knee joint. After confirmation of the needle tip location, a dilute gadolinium solution was injected.Results and conclusion. All the arthrograms were technically successful. The anterior approach to knee MRA has greater technical ease than the traditional approach with little patient discomfort. (orig.)

  7. An Approach to Interface Synthesis

    DEFF Research Database (Denmark)

    Madsen, Jan; Hald, Bjarne

    1995-01-01

    Presents a novel interface synthesis approach based on a one-sided interface description. Whereas most other approaches consider interface synthesis as optimizing a channel to existing client/server modules, we consider the interface synthesis as part of the client/server module synthesis (which...... may contain the re-use of existing modules). The interface synthesis approach describes the basic transformations needed to transform the server interface description into an interface description on the client side of the communication medium. The synthesis approach is illustrated through a point......-to-point communication, but is applicable to synthesis of a multiple client/server environment. The interface description is based on a formalization of communication events....

  8. Nonlinear Approaches in Engineering Applications

    CERN Document Server

    Jazar, Reza

    2012-01-01

    Nonlinear Approaches in Engineering Applications focuses on nonlinear phenomena that are common in the engineering field. The nonlinear approaches described in this book provide a sound theoretical base and practical tools to design and analyze engineering systems with high efficiency and accuracy and with less energy and downtime. Presented here are nonlinear approaches in areas such as dynamic systems, optimal control and approaches in nonlinear dynamics and acoustics. Coverage encompasses a wide range of applications and fields including mathematical modeling and nonlinear behavior as applied to microresonators, nanotechnologies, nonlinear behavior in soil erosion,nonlinear population dynamics, and optimization in reducing vibration and noise as well as vibration in triple-walled carbon nanotubes. This book also: Provides a complete introduction to nonlinear behavior of systems and the advantages of nonlinearity as a tool for solving engineering problems Includes applications and examples drawn from the el...

  9. Paraspinal approach for thoracolumbar fracture

    Directory of Open Access Journals (Sweden)

    JIANG Rui

    2011-02-01

    Full Text Available 【Abstract】Objective: To explore the advantages and indications of the paraspinal approach by anatomical study and clinical application. Methods: The anatomical data and clinical practice of 27 cases were analyzed to explore the accurate approach between the paraspinal muscles and the structure of ambient tissues, as well as the results of clinical application of paraspinal approach. The operation time, blood loss, incision length, radiographic result (Cobb angle, height of anterior edge of the vertebrae were compared with those in 24 cases treated by traditional approach. Results: Complete exposure of the facets could be easily performed by identifying natural cleavage plane between the multifidus and longissimus muscles. The natural muscular cleavage was (1.47±0.23 cm lateral to the midline for females, and (1.64±0.35 cm for males at T12 level. The distance was (3.3±0.6 cm lateral to the midline for females, and (3.7±1.0 cm for males at L4 level. In paraspinal approach group, the operation time was (76.2±15.7 min, blood loss was (91.6±16.9 ml and incision length was (7.6±0.8 cm. In traditional approach group, the operation time was (121.4±19.6 min, blood loss was (218.7±32.3 ml and incision length was (17.4±2.1 cm. To compare paraspinal approach with traditional approach, the operation time, blood loss and incision length had statistical difference (P<0.05 and the radiographic result (Cobb angle, height of anterior edge of the vertebrae had no statistical difference (P>0.05. Conclusions: When the paraspinal approach is performed through natural cleavage plane between the multifidus and longissimus muscles, there are no wide muscular disinsertions, leaving the supraspinous and interspinous ligaments intact. The distance of natural cleavage to the midline is different at T12 and L4 planes. By this approach, the facet joints can be explored easily and completely, and a clear surgical field will be available for the placement of

  10. Bounding approaches to system identification

    CERN Document Server

    Norton, John; Piet-Lahanier, Hélène; Walter, Éric

    1996-01-01

    In response to the growing interest in bounding error approaches, the editors of this volume offer the first collection of papers to describe advances in techniques and applications of bounding of the parameters, or state variables, of uncertain dynamical systems. Contributors explore the application of the bounding approach as an alternative to the probabilistic analysis of such systems, relating its importance to robust control-system design.

  11. Approaches toward learning in physiotherapy

    Directory of Open Access Journals (Sweden)

    L. Keiller

    2013-11-01

    Full Text Available The aim of this study was to investigate the approaches toward learning of undergraduate Physiotherapy students in a PBl module to enhance facilitation of learning at the Stellenbosch University, Division of Physiotherapy in South Africa. This quantitative, descriptive study utilized the revised Two-factor Study Process Questionnaire (r-SPQ-2f to evaluate the study cohorts’ approaches toward learning in the module. results of the data instruments were analysed statistically and discussed in a descriptive manner. There were a statistically significant greater number of students who adopted a deep approach toward learning at the commencement of the academic year. Students showed a trend toward an increase in their intrinsic interest in the learning material as the module progressed. Students in the Applied Physiotherapy module (ATP started to shift their focus from a surface learning approach to a deep learning approach. further research is needed to determine the long-term changes in approach toward learning and the possible determinants of these changes. This can be done in conjunction with the implementation of quality assurance mechanisms for learning material and earlier preparation of students for the change in the learning environment.

  12. Cushing disease revealed by bilateral atypical central serous chorioretinopathy: case report.

    Science.gov (United States)

    Giovansili, Iama; Belange, Georeges; Affortit, Aude

    2013-01-01

    We report the case of a patient with Cushing disease revealed by bilateral central serous chorioretinopathy (CSCR). We present the clinical history, physical findings, laboratory results, and imaging studies of a 53-year-old Chinese woman with a Cushing disease revealed by bilateral CSCR. The association with CSCR and the pertinent literature are reviewed. A 53-year-old patient initially presented to the Department of Ophthalmology with a 4-week history of decreased vision in the left eye. Standard ophthalmologic examination and fluorescein angiography established the diagnosis of bilateral CSCR. Systemic clinical signs and biochemical analysis indicated hypercortisolism. Magnetic resonance imaging (MRI) of the pituitary gland showed a left-side lesion compatible with a microadenoma. The diagnosis of Adrenocorticotropic hormone (ACTH)-dependent Cushing syndrome secondary to a pituitary microadenoma was selected. Endoscopic endonasal transsphenoidal surgery was performed and the pituitary adenoma was successfully removed. The histology confirmed the presence of ACTH-immunopositive pituitary adenoma. Early postoperative morning cortisol levels indicated early remission. At 6 weeks postoperatively, the patient's morning cortisol remains undetectable, and serous retinal detachments had regressed. CSCR is an uncommon manifestation of endogenous Cushing syndrome. It can be the first presentation of hypercortisolism caused by Cushing disease. CSCR should be considered when assessing patients with Cushing syndrome complaining of visual disorders. On the other hand, it is useful in patients with an atypical form of CSCR to exclude Cushing's syndrome.

  13. Approach

    Directory of Open Access Journals (Sweden)

    Guido Pinto Aguirre

    2008-01-01

    Full Text Available El propósito de este documento es investigar y re-estimar los efectos de los patrones de lactancia, salud y estado nutricional de la mujer y consumo de energía sobre la duración del retorno de la fertilidad de postparto (es decir, retorno de la menstruación de postparto utilizando toda la información relevante en el estudio longitudinal del Instituto de Nutrición de Centroamérica y Panamá y un procedimiento de estimación más adecuado (modelos de riesgo. Los datos utilizados provienen del Estudio Longitudinal llevado a cabo en Guatemala entre 1967 y 1979. En este artículo se utiliza un modelo de riesgo con varios estados que reconoce diferentes caminos y estados en el proceso del retorno de la fertilidad de postparto. El modelo descansa en la existencia de cinco estados (lactancia total, lactancia parcial, destete, mortalidad infantil y menstruación. También incluye de manera explícita nutrición maternal y consumo de energía de la mujer como elementos estratégicos del modelo. El estudio encontró que los efectos de los patrones de lactancia, nutrición de la madre y patrones de trabajo de la mujer (consumo de energía sobre la fertilidad en las áreas rurales de Guatemala son fuertes y significativos. La contribución de este artículo es mostrar que la aplicación de los modelos de riesgo con múltiples estados proporciona estimados que son consistentes con hipótesis que relacionan patrones de lactancia, estado nutricional maternal y estresores maternales externos a procesos que aceleran (desaceleran el retorno de ciclos menstruales normales.

  14. Strain expansion-reduction approach

    Science.gov (United States)

    Baqersad, Javad; Bharadwaj, Kedar

    2018-02-01

    Validating numerical models are one of the main aspects of engineering design. However, correlating million degrees of freedom of numerical models to the few degrees of freedom of test models is challenging. Reduction/expansion approaches have been traditionally used to match these degrees of freedom. However, the conventional reduction/expansion approaches are only limited to displacement, velocity or acceleration data. While in many cases only strain data are accessible (e.g. when a structure is monitored using strain-gages), the conventional approaches are not capable of expanding strain data. To bridge this gap, the current paper outlines a reduction/expansion technique to reduce/expand strain data. In the proposed approach, strain mode shapes of a structure are extracted using the finite element method or the digital image correlation technique. The strain mode shapes are used to generate a transformation matrix that can expand the limited set of measurement data. The proposed approach can be used to correlate experimental and analytical strain data. Furthermore, the proposed technique can be used to expand real-time operating data for structural health monitoring (SHM). In order to verify the accuracy of the approach, the proposed technique was used to expand the limited set of real-time operating data in a numerical model of a cantilever beam subjected to various types of excitations. The proposed technique was also applied to expand real-time operating data measured using a few strain gages mounted to an aluminum beam. It was shown that the proposed approach can effectively expand the strain data at limited locations to accurately predict the strain at locations where no sensors were placed.

  15. [Modern treatment approaches to gambling].

    Science.gov (United States)

    Egorov, A Iu

    2014-01-01

    Compulsive gambling has received widespread attention in the last decade. Gambling has become the first non-chemical addiction, which went down to the section "Addiction and related disorders" of the modern DSM-V. The review considers non-pharmacological and pharmacological approaches to the treatment of gambling. Among non-drug approaches, cognitive-behavioral therapy and 12-step programs have gained the most popularity in the "Gamblers Anonymous" community. Among pharmacological approaches, three classes of drugs: antidepressants (mainly SSRIs), opiate antagonists (naltrexone and nalmefene) and mood stabilizers (valproate, lithium, topiramate) proved to be effective in treatment of gambling. No differences in the efficacy of the three classes of psychotropic drugs have been identified. Preliminary results for N-acetylcysteine and memantine cause optimism in terms of perspective.

  16. Project Supervision - An Engineering Approach

    DEFF Research Database (Denmark)

    Paulsen, Rasmus Reinhold; Larsen, Rasmus; Ersbøll, Bjarne Kjær

    2011-01-01

    For more than twenty years, a group based supervision strategy has been used when supervising engineering bachelor- and master thesis students at our research group. In recent years, we have formalised the approach and used our industry experience to create a very successful framework for project...... supervision. This paper is a best practice guide aiming at research groups that would like to try to implement our supervision approach or parts of it. The approach is based on the belief that engineering students should be prepared for their new role as development engineers or PhD students as part...... of their master thesis writing. The supervision principles are: Ownership: The student should feel that their project is their own. Ideally, they should formulate the project themselves. Write early: We strongly encourage the students to write and generate figures and images already from the first week...

  17. Toward predicate approaches to modality

    CERN Document Server

    Stern, Johannes

    2016-01-01

    In this volume, the author investigates and argues for, a particular answer to the question: What is the right way to logically analyze modalities from natural language within formal languages? The answer is: by formalizing modal expressions in terms of predicates. But, as in the case of truth, the most intuitive modal principles lead to paradox once the modal notions are conceived as predicates. The book discusses the philosophical interpretation of these modal paradoxes and argues that any satisfactory approach to modality will have to face the paradoxes independently of the grammatical category of the modal notion. By systematizing modal principles with respect to their joint consistency and inconsistency, Stern provides an overview of the options and limitations of the predicate approach to modality that may serve as a useful starting point for future work on predicate approaches to modality. Stern also develops a general strategy for constructing philosophically attractive theories of modal notions conce...

  18. Two Approaches to Entrepreneurship Education

    DEFF Research Database (Denmark)

    Moberg, Kåre

    2014-01-01

    The objective of this paper is to analyse the influence of two different approaches to entrepreneurship education at the lower secondary level of education. The influence of education for entrepreneurship and education through entrepreneurship on pupils' level of school engagement and entrepreneu......The objective of this paper is to analyse the influence of two different approaches to entrepreneurship education at the lower secondary level of education. The influence of education for entrepreneurship and education through entrepreneurship on pupils' level of school engagement...... ninth-graders (aged 14e15) and 576 randomly selected Danish tenth-graders (aged 15e16). The findings have implications for policy makers and curriculum designers, inasmuch as the influence of two educational approaches is assessed and analysed, but also for the academic community since it presents...

  19. Solid mechanics a variational approach

    CERN Document Server

    Dym, Clive L

    2013-01-01

    Solid Mechanics: A Variational Approach, Augmented Edition presents a lucid and thoroughly developed approach to solid mechanics for students engaged in the study of elastic structures not seen in other texts currently on the market. This work offers a clear and carefully prepared exposition of variational techniques as they are applied to solid mechanics. Unlike other books in this field, Dym and Shames treat all the necessary theory needed for the study of solid mechanics and include extensive applications. Of particular note is the variational approach used in developing consistent structural theories and in obtaining exact and approximate solutions for many problems.  Based on both semester and year-long courses taught to undergraduate seniors and graduate students, this text is geared for programs in aeronautical, civil, and mechanical engineering, and in engineering science. The authors’ objective is two-fold: first, to introduce the student to the theory of structures (one- and two-dimensional) as ...

  20. City evacuations an interdisciplinary approach

    CERN Document Server

    Binner, Jane; Branicki, Layla; Galla, Tobias; Jones, Nick; King, James; Kolokitha, Magdalini; Smyrnakis, Michalis

    2015-01-01

    Evacuating a city is a complex problem that involves issues of governance, preparedness education, warning, information sharing, population dynamics, resilience and recovery. As natural and anthropogenic threats to cities grow, it is an increasingly pressing problem for policy makers and practitioners.   The book is the result of a unique interdisciplinary collaboration between researchers in the physical and social sciences to consider how an interdisciplinary approach can help plan for large scale evacuations.  It draws on perspectives from physics, mathematics, organisation theory, economics, sociology and education.  Importantly it goes beyond disciplinary boundaries and considers how interdisciplinary methods are necessary to approach a complex problem involving human actors and increasingly complex communications and transportation infrastructures.   Using real world case studies and modelling the book considers new approaches to evacuation dynamics.  It addresses questions of complexity, not only ...

  1. Market-based approaches to tree valuation

    Science.gov (United States)

    Geoffrey H. Donovan; David T. Butry

    2008-01-01

    A recent four-part series in Arborist News outlined different appraisal processes used to value urban trees. The final article in the series described the three generally accepted approaches to tree valuation: the sales comparison approach, the cost approach, and the income capitalization approach. The author, D. Logan Nelson, noted that the sales comparison approach...

  2. Three Approaches to High School Classroom Music.

    Science.gov (United States)

    O'Brien, Wanda

    1985-01-01

    Three process-oriented approaches to high school classroom music--the problem-solving approach, the aesthetic criticism approach, and the interrelated fine arts approach--are discussed. These three approaches are recommended for curriculum reform related to the national reports. (RM)

  3. Systems biology approach to bioremediation

    Energy Technology Data Exchange (ETDEWEB)

    Chakraborty, Romy; Wu, Cindy H.; Hazen, Terry C.

    2012-06-01

    Bioremediation has historically been approached as a ‘black box’ in terms of our fundamental understanding. Thus it succeeds and fails, seldom without a complete understanding of why. Systems biology is an integrated research approach to study complex biological systems, by investigating interactions and networks at the molecular, cellular, community, and ecosystem level. The knowledge of these interactions within individual components is fundamental to understanding the dynamics of the ecosystem under investigation. Finally, understanding and modeling functional microbial community structure and stress responses in environments at all levels have tremendous implications for our fundamental understanding of hydrobiogeochemical processes and the potential for making bioremediation breakthroughs and illuminating the ‘black box’.

  4. Time use-economic approaches.

    Science.gov (United States)

    Hamermesh, Daniel S

    2018-03-26

    I describe an economic approach to studying time use. The literature has applied this approach to analyzing: differences and changes in work time; the gender division of chores; the determinants of the split of time outside work; differences in time use and time stress by earnings and household income; how the artificial constructs of time zones and summer time affect what people do and when they do it; how and why non-work time is used differently by race, gender and age; and how people would use non-work time if they had more. Copyright © 2018 Elsevier Ltd. All rights reserved.

  5. Elementary calculus an infinitesimal approach

    CERN Document Server

    Keisler, H Jerome

    2012-01-01

    This first-year calculus book is centered around the use of infinitesimals, an approach largely neglected until recently for reasons of mathematical rigor. It exposes students to the intuition that originally led to the calculus, simplifying their grasp of the central concepts of derivatives and integrals. The author also teaches the traditional approach, giving students the benefits of both methods.Chapters 1 through 4 employ infinitesimals to quickly develop the basic concepts of derivatives, continuity, and integrals. Chapter 5 introduces the traditional limit concept, using approximation p

  6. A Psycho-Societal Approach

    DEFF Research Database (Denmark)

    Mellon, Karsten

    This is a project about Danish vocational bachelor students admitted on the basis of an Individual Competency Assessment (VPL/IKV) in light of a Psycho-Societal Approach. The core idea of this paper is to present a PhD project which aims to contribute findings regarding students enrolled in a Dan......This is a project about Danish vocational bachelor students admitted on the basis of an Individual Competency Assessment (VPL/IKV) in light of a Psycho-Societal Approach. The core idea of this paper is to present a PhD project which aims to contribute findings regarding students enrolled...

  7. Synergistic approach to patient dialysate.

    Science.gov (United States)

    Dragotoiu, A; Checheriţă, A I; Ciocâlteu, A; Rizeanu, S

    2015-01-01

    The stress a patient is subjected to during dialysis treatment can be reduced by using a synergetic approach by the medical team. The integration into therapy of the positive psychical resources such as: active positive coping mechanisms, individual or family mental resilience, improvement of the image and self-esteem, better tolerance to frustration can represent an important part in the improvement of the patient's quality of life, determination of a positive approach of the situations both for him and close friends and relatives.

  8. New Approaches to Reliability Assessment

    DEFF Research Database (Denmark)

    Ma, Ke; Wang, Huai; Blaabjerg, Frede

    2016-01-01

    of energy. New approaches for reliability assessment are being taken in the design phase of power electronics systems based on the physics-of-failure in components. In this approach, many new methods, such as multidisciplinary simulation tools, strength testing of components, translation of mission profiles......, and statistical analysis, are involved to enable better prediction and design of reliability for products. This article gives an overview of the new design flow in the reliability engineering of power electronics from the system-level point of view and discusses some of the emerging needs for the technology...

  9. Gender Differences in Disciplinary Approaches.

    Science.gov (United States)

    Rodriguez, Nixaliz

    This study explored differences in disciplinary approaches of male and female teachers toward male and female children, examining the connection between educator's gender and method of disciplining urban, elementary school aged children. Participants were 20 New York State certified and licensed teachers in two elementary schools. Teacher surveys…

  10. Coaching Humanistically: An Alternative Approach.

    Science.gov (United States)

    Danziger, Raymond Curtis

    1982-01-01

    Four goals for a humanistic approach to athletics are: (1) elevating perception of students' physical abilities to improve self-esteem; (2) encouraging self-actualization; (3) contributing to self-understanding; and (4) improving interpersonal relationships. Implications of these objectives for team management, competition, and the attitudes of…

  11. Integrated reclamation: Approaching ecological function?

    Science.gov (United States)

    Ann L. Hild; Nancy L. Shaw; Ginger B. Paige

    2009-01-01

    Attempts to reclaim arid and semiarid lands have traditionally targeted plant species composition. Much research attention has been directed to seeding rates, species mixes and timing of seeding. However, in order to attain functioning systems, attention to structure and process must compliment existing efforts. We ask how to use a systems approach to enhance...

  12. A Psychoanalytic Approach to Fieldwork

    Science.gov (United States)

    Ramvi, Ellen

    2012-01-01

    This article focuses on what both psychoanalysis and anthropology have in common: the emphasis on the researcher's own experience. An ethnographic fieldwork will be used to illustrate how a psychoanalytical approach unfolds the material when studying conditions for learning from experience among teachers in two Norwegian junior high schools, and…

  13. International Approaches to Clinical Costing

    DEFF Research Database (Denmark)

    Chapman, Christopher; Kern, Anja; Laguecir, Aziza

    This report has been commissioned by both HFMA and Monitor and the work has been led by Imperial College Business School’s Health Management Group. The report compares current approaches to costing, primarily across Europe. The findings reveal wide-ranging practices and uses for costing data...

  14. Eschenmoser Approach to Vitamin B

    Indian Academy of Sciences (India)

    Home; Journals; Resonance – Journal of Science Education; Volume 19; Issue 7. Eschenmoser Approach to Vitamin B12 by A/D Strategy: An Unexpected Journey. G Wayne Craig. General Article Volume 19 Issue 7 July 2014 pp 624-640. Fulltext. Click here to view fulltext PDF. Permanent link:

  15. Ecological approaches to human nutrition.

    Science.gov (United States)

    DeClerck, Fabrice A J; Fanzo, Jessica; Palm, Cheryl; Remans, Roseline

    2011-03-01

    Malnutrition affects a large number of people throughout the developing world. Approaches to reducing malnutrition rarely focus on ecology and agriculture to simultaneously improve human nutrition and environmental sustainability. However, evidence suggests that interdisciplinary approaches that combine the knowledge bases of these disciplines can serve as a central strategy in alleviating hidden hunger for the world's poorest. To describe the role that ecological knowledge plays in alleviating hidden hunger, considering human nutrition as an overlooked ecosystem service. We review existing literature and propose a framework that expands on earlier work on econutrition. We provide novel evidence from case studies conducted by the authors in western Kenya and propose a framework for interdisciplinary collaboration to alleviate hidden hunger, increase agricultural productivity, and improve environmental sustainability. Our review supports the concept that an integrated approach will impact human nutrition. We provide evidence that increased functional agrobiodiversity can alleviate anemia, and interventions that contribute to environmental sustainability can have both direct and indirect effects on human health and nutritional well-being. Integrated and interdisciplinary approaches are critical to reaching development goals. Ecologists must begin to consider not only how their field can contribute to biodiversity conservation, but also, the relationship between biodiversity and provisioning of nontraditional ecosystem services such as human health. Likewise, nutritionists and agronomists must recognize that many of the solutions to increasing human wellbeing and health can best be achieved by focusing on a healthy environment and the conservation of ecosystem services.

  16. Taste as a didactic approach

    DEFF Research Database (Denmark)

    Wistoft, Karen; Christensen, Jacob

    2016-01-01

    Teaching does not necessarily condition learning, and specific didactic elements do not necessarily condition the best learning outcome; this also applies to ‘food and meal’ lessons in schools. Teachers’ didactic reflections usually reflect the content and form of the teaching, as well as a numbe...... as a didactic approach in enabling students to achieve learning goals....

  17. Taste is a didactic approach

    DEFF Research Database (Denmark)

    Christensen, Jacob Højgaard

    2015-01-01

    Teaching does not necessarily condition learning, and specific didactic elements do not necessarily condition the best learning outcome; this also applies to ‘food and meal’ lessons in schools. Teachers’ didactic reflections usually reflect the content and form of the teaching, as well as a numbe...... as a didactic approach in enabling students to achieve learning goals....

  18. Dental approach to craniofacial syndromes

    DEFF Research Database (Denmark)

    Kjær, Inger

    2012-01-01

    is essential for insight into craniofacial syndromes. The dentition, thus, becomes central in diagnostics and evaluation of the pathogenesis. Developmental fields can explore and advance the concept of dental approaches to craniofacial syndromes. Discussion. As deviations in teeth persist and do not reorganize...

  19. Approaches to translational plant science

    DEFF Research Database (Denmark)

    Dresbøll, Dorte Bodin; Christensen, Brian; Thorup-Kristensen, Kristian

    2015-01-01

    is lessened. In our opinion, implementation of translational plant science is a necessity in order to solve the agricultural challenges of producing food and materials in the future. We suggest an approach to translational plant science forcing scientists to think beyond their own area and to consider higher...

  20. Possibilistic approach to target classification

    NARCIS (Netherlands)

    Huizing, A.G.; Groen, F.C.A.

    2000-01-01

    Abstract: This chapter describes an alternative to the Bayesian approach to target classification that is based on possibility theory. A possibilistic classifier minimizes the maximum cost of the classification decision taking into account the a posteriori possibilities of the target classes given

  1. Approaching Environmental Issues in Architecture

    DEFF Research Database (Denmark)

    Petersen, Mads Dines; Knudstrup, Mary-Ann

    2013-01-01

    The research presented here takes its point of departure in the design process with a specific focus on how it is approached when designing energy efficient architecture. This is done through a case-study of a design process in a Danish architectural office. This study shows the importance...

  2. An Integrated Approach to Biology

    Indian Academy of Sciences (India)

    An Integrated Approach to Biology. Aniket Bhattacharya. Keywords. Zoology, genomics, schistoso- miasis, schistosome genomics, praziquantel, origin of clothing. Zoology, being a basic bioscience, is essential for a better understanding of applied biological disciplines. A sound back- ground in zoology can often be the key ...

  3. Multidisciplinary Approaches in Evolutionary Linguistics

    Science.gov (United States)

    Gong, Tao; Shuai, Lan; Wu, Yicheng

    2013-01-01

    Studying language evolution has become resurgent in modern scientific research. In this revival field, approaches from a number of disciplines other than linguistics, including (paleo)anthropology and archaeology, animal behaviors, genetics, neuroscience, computer simulation, and psychological experimentation, have been adopted, and a wide scope…

  4. Organ donation: a communitarian approach.

    Science.gov (United States)

    Etzioni, Amitai

    2003-03-01

    Recently, various suggestions have been made to respond to the increasingly great shortage of organs by paying for them. Because of the undesirable side effects of such approaches (commodification, injustice, and costs), a communitarian approach should be tried first. A communitarian approach to the problem of organ shortage entails changing the moral culture so that members of society will recognize that donating one's organs, once they are no longer of use to the donor, is the moral (right) thing to do. This approach requires much greater and deeper efforts than sharing information and making public service announcements. It entails a moral dialogue, in which the public is engaged, leading to a change in what people expect from one another. Among the devices that could help change the moral culture are a public statement, endorsed by community members and leaders, that expresses the community sense that donation "is what a good person does" and a community-specific web page that lists those who have made the commitment. A change in law so that a person's wishes in the matter are recognized as final and binding are also desired. This position paper deals only with cadaver organs and not living donors.

  5. A Waste Management Hierarchy Approach

    African Journals Online (AJOL)

    The purpose of the study was to identify the gaps between existing practices and the provisions of the hierarchy of waste management model in the Nadowli Township of the Upper West Region of Ghana. A cross-sectional study design with quantitative and qualitative approaches was adopted and questionnaires, ...

  6. Classical approach in atomic physics

    International Nuclear Information System (INIS)

    Solov'ev, E.A.

    2011-01-01

    The application of a classical approach to various quantum problems - the secular perturbation approach to quantization of a hydrogen atom in external fields and a helium atom, the adiabatic switching method for calculation of a semiclassical spectrum of a hydrogen atom in crossed electric and magnetic fields, a spontaneous decay of excited states of a hydrogen atom, Gutzwiller's approach to Stark problem, long-lived excited states of a helium atom discovered with the help of Poincare section, inelastic transitions in slow and fast electron-atom and ion-atom collisions - is reviewed. Further, a classical representation in quantum theory is discussed. In this representation the quantum states are treated as an ensemble of classical states. This approach opens the way to an accurate description of the initial and final states in classical trajectory Monte Carlo (CTMC) method and a purely classical explanation of tunneling phenomenon. The general aspects of the structure of the semiclassical series such as renormalization group symmetry, criterion of accuracy and so on are reviewed as well. (author)

  7. A Freudian Approach to Education.

    Science.gov (United States)

    Gartner, Sandra L.

    This document offers the point of view that Bruno Bettelheim's writings, based on Sigmund Freud's approach to education, suggest the most practical applications for achieving positive results within the classroom. The overall result of a student being taught all through school by the Freudian method would be an extremely positive one. Such a…

  8. Oncoplastic Approaches to Breast Conservation

    Directory of Open Access Journals (Sweden)

    Dennis R. Holmes

    2011-01-01

    Full Text Available When a woman is diagnosed with breast cancer many aspects of her physical, emotional, and sexual wholeness are threatened. The quickly expanding field of oncoplastic breast surgery aims to enhance the physician commitment to restore the patient's image and self-assurance. By combining a multidisciplinary approach to diagnosis and treatment with oncoplastic surgery, successful results in the eyes of the patient and physician are significantly more likely to occur. As a way to aid oncoplastic teams in determining which approach is most suitable for their patient's tumor size, tumor location, body habitus, and desired cosmetic outcome we present a review of several oncoplastic surgical approaches. For resections located anywhere in the breast, the radial ellipse segmentectomy incision and circumareolar approach for segmental resection are discussed. For resections in the upper or central breast, crescent mastopexy, the batwing incision, the hemibatwing incision, donut mastopexy, B-flap resection, and the central quadrantectomy are reviewed. For lesions of the lower breast, the triangle incision, inframammary incision, and reduction mastopexy are discussed. Surgeons who are interested in adding oncoplastic breast conserving therapies to their skill sets are encouraged to implement these surgical techniques where applicable and to seek out breast fellowships or enhanced training when appropriate.

  9. Fundamental Approaches to Software Engineering

    NARCIS (Netherlands)

    Gnesi, S.; Rensink, Arend; Unknown, [Unknown

    This volume contains the proceedings of FASE 2014, the 17th International Conferences on Fundamental Approaches to Software Engineering, which was held in Grenoble, Italy, in April 2014 as part of the annual European Joint Conferences on Theory and Practice of Software (ETAPS).

  10. An analogical approach to grammaticalization

    NARCIS (Netherlands)

    Fischer, O.; Stathi, K.; Gehweiler, E.; König, E.

    2010-01-01

    Two well-known approaches to language change illustrate a fundamental difference between functional and formal linguistics as to what are considered important mechanisms in change. In Grammaticalization, emphasis is on the semantic-pragmatic factors guiding change, while Generative Theory

  11. Four Approaches to "Authentic" Reading.

    Science.gov (United States)

    Valette, Rebecca M.

    1997-01-01

    Examines the types of readings students are likely to encounter in the "real" world and how they will interact with them. The four approaches discussed include reading in a daily-life context, reading for information, reading for pleasure, and participatory reading. (21 references) (Author/CK)

  12. Tiered Approach to Resilience Assessment.

    Science.gov (United States)

    Linkov, Igor; Fox-Lent, Cate; Read, Laura; Allen, Craig R; Arnott, James C; Bellini, Emanuele; Coaffee, Jon; Florin, Marie-Valentine; Hatfield, Kirk; Hyde, Iain; Hynes, William; Jovanovic, Aleksandar; Kasperson, Roger; Katzenberger, John; Keys, Patrick W; Lambert, James H; Moss, Richard; Murdoch, Peter S; Palma-Oliveira, Jose; Pulwarty, Roger S; Sands, Dale; Thomas, Edward A; Tye, Mari R; Woods, David

    2018-04-25

    Regulatory agencies have long adopted a three-tier framework for risk assessment. We build on this structure to propose a tiered approach for resilience assessment that can be integrated into the existing regulatory processes. Comprehensive approaches to assessing resilience at appropriate and operational scales, reconciling analytical complexity as needed with stakeholder needs and resources available, and ultimately creating actionable recommendations to enhance resilience are still lacking. Our proposed framework consists of tiers by which analysts can select resilience assessment and decision support tools to inform associated management actions relative to the scope and urgency of the risk and the capacity of resource managers to improve system resilience. The resilience management framework proposed is not intended to supplant either risk management or the many existing efforts of resilience quantification method development, but instead provide a guide to selecting tools that are appropriate for the given analytic need. The goal of this tiered approach is to intentionally parallel the tiered approach used in regulatory contexts so that resilience assessment might be more easily and quickly integrated into existing structures and with existing policies. Published 2018. This article is a U.S. government work and is in the public domain in the USA.

  13. Nuclear regulation - the Canadian approach

    International Nuclear Information System (INIS)

    Jennekens, J.

    1981-09-01

    Although the Atomic Energy Control Board was established 35 years ago the basic philosophy of nuclear regulation in Canada and the underlying principles of the regulatory process remain essentially unchanged. This paper outlines the Canadian approach to nuclear regulation and explains in practical terms how the principles of regulation are applied. (author)

  14. An Integrated Approach to Biology

    Indian Academy of Sciences (India)

    Home; Journals; Resonance – Journal of Science Education; Volume 16; Issue 8. An Integrated Approach to Biology. Aniket Bhattacharya. General Article Volume 16 Issue 8 August 2011 pp 742-753 ... Keywords. Zoology; genomics; schistosomiasis; schistosome genomics; praziquantel; origin of clothing.

  15. Institutional Planning: A Systems Approach.

    Science.gov (United States)

    Adamson, Willie D.

    This four-chapter report explores the possible contributions of a systems approach to institutional planning. After introductory comments, Chapter I reviews the management theory of Henry Fayol, which emphasizes management tasks, such as planning, organizing, commanding, coordinating, and controlling, which are "universal" regardless of the level…

  16. Molecular approaches to contraceptive development

    Indian Academy of Sciences (India)

    Unknown

    Molecular approaches for contraceptive development rely on the identification of genes and target validation. Some major genomic technologies for identification of gene targets are: expressed sequence tags (est), secreted protein analysis, differential display (Liang and Pardee. 1992), DNA micro array (Debouck and ...

  17. A Discovery Approach to Movement.

    Science.gov (United States)

    O'Hagin, Isabel B.

    1998-01-01

    Investigates the effects of the discovery approach to movement-based instruction on children's level of musicality. Finds that the students with the highest musicality were girls, demonstrated reflective movements and a personal sense of style while moving, and made sense of the music by organizing, categorizing, and developing movement ideas.…

  18. Integrative approaches: promoting socioecological resilience

    Science.gov (United States)

    J.W. Long; Carl Skinner; M. North; C.T. Hunsaker; L. Quinn-Davidson

    2014-01-01

    This chapter begins by discussing current challenges for ecosystem management that emerged from multiple chapters of the full synthesis. It then considers integrative approaches to promote resilience, including general strategies that recognize the integrated nature of socioecological systems, the importance of promoting disturbance regimes upon which these systems...

  19. Appreciating Music: An Active Approach

    Science.gov (United States)

    Levin, Andrew R.; Pargas, Roy P.

    2005-01-01

    A particularly innovative use of laptops is to enhance the music appreciation experience. Group listening and discussion, in combination with a new Web-based application, lead to deeper understanding of classical music. ["Appreciating Music: An Active Approach" was written with Joshua Austin.

  20. Cleft Palate; A Multidiscipline Approach.

    Science.gov (United States)

    Stark, Richard B., Ed.

    Nineteen articles present a multidisciplinary approach to the management of facial clefts. The following subjects are discussed: the history of cleft lip and cleft palate surgery; cogenital defects; classification; the operation of a cleft palate clinic; physical examination of newborns with cleft lip and/or palate; nursing care; anesthesia;…

  1. Approaching Bose-Einstein Condensation

    Science.gov (United States)

    Ferrari, Loris

    2011-01-01

    Bose-Einstein condensation (BEC) is discussed at the level of an advanced course of statistical thermodynamics, clarifying some formal and physical aspects that are usually not covered by the standard pedagogical literature. The non-conventional approach adopted starts by showing that the continuum limit, in certain cases, cancels out the crucial…

  2. Corpus Approaches to Language Ideology

    Science.gov (United States)

    Vessey, Rachelle

    2017-01-01

    This paper outlines how corpus linguistics--and more specifically the corpus-assisted discourse studies approach--can add useful dimensions to studies of language ideology. First, it is argued that the identification of words of high, low, and statistically significant frequency can help in the identification and exploration of language ideologies…

  3. Low current approach to ignition

    International Nuclear Information System (INIS)

    Cenacchi, G.; Sugiyama, L.; Airoldi, A.; Coppi, B.

    1996-01-01

    The open-quotes standardclose quotes path to achieve ignition conditions so far has been that of producing plasmas with the maximum current and poloidal field that axe compatible with the applied toroidal field and the geometry of the adopted configuration (the low q a approach.) The other approach is that motivated by recent experiments with reversed shear configurations, with relatively low currents and high fields corresponding to high values of q a (e-g., q a ≅ 6). While the first approach can be pursued with ohmic heating alone, the second one necessarily involves an auxiliary heating system. One of the advantages of this approach is that the onset of large scale internal modes can be avoided as q(ψ) is kept above 1 over the entire plasma column. Since quite peaked density profiles are produced in the regimes where enhanced confinement is observed, the α-particle power levels for which ignition can be reached and therefore the thermal wall loading on the first wall, can be reduced relatively to the standard, low q a , approach. The possibility is considered that ignition is reached in the reversed shear, high q a , regime and that this is followed by a transition to non-reversed profiles, or even the low q a regime, assuming that the excitation of modes involving magnetic reconnection will not undermine the needed degree of confinement. These results have been demonstrated by numerical transport simulation for the Ignitor-Ult machine, but are applicable to all high field ignition experiments

  4. Minimalist approach to perceptual interactions.

    Science.gov (United States)

    Lenay, Charles; Stewart, John

    2012-01-01

    WORK AIMED AT STUDYING SOCIAL COGNITION IN AN INTERACTIONIST PERSPECTIVE OFTEN ENCOUNTERS SUBSTANTIAL THEORETICAL AND METHODOLOGICAL DIFFICULTIES: identifying the significant behavioral variables; recording them without disturbing the interaction; and distinguishing between: (a) the necessary and sufficient contributions of each individual partner for a collective dynamics to emerge; (b) features which derive from this collective dynamics and escape from the control of the individual partners; and (c) the phenomena arising from this collective dynamics which are subsequently appropriated and used by the partners. We propose a minimalist experimental paradigm as a basis for this conceptual discussion: by reducing the sensory inputs to a strict minimum, we force a spatial and temporal deployment of the perceptual activities, which makes it possible to obtain a complete recording and control of the dynamics of interaction. After presenting the principles of this minimalist approach to perception, we describe a series of experiments on two major questions in social cognition: recognizing the presence of another intentional subject; and phenomena of imitation. In both cases, we propose explanatory schema which render an interactionist approach to social cognition clear and explicit. Starting from our earlier work on perceptual crossing we present a new experiment on the mechanisms of reciprocal recognition of the perceptual intentionality of the other subject: the emergent collective dynamics of the perceptual crossing can be appropriated by each subject. We then present an experimental study of opaque imitation (when the subjects cannot see what they themselves are doing). This study makes it possible to characterize what a properly interactionist approach to imitation might be. In conclusion, we draw on these results, to show how an interactionist approach can contribute to a fully social approach to social cognition.

  5. Maxillary bone myxoma.

    Science.gov (United States)

    Zainine, R; Mizouni, H; El Korbi, A; Beltaief, N; Sahtout, S; Besbes, G

    2014-09-01

    Maxillary bone myxoma is a rare benign mesenchymal tumor, slow-growing but locally aggressive. Pathogenesis remains disputed. To study the clinical, radiological and histological features and treatment of maxillary myxoma, based on a pediatric case report. An infant of two and a half months presented with endonasal tumor extending to ethmoid. Surgical excision was performed on an endonasal approach. Myxoma was diagnosed by histologic examination of the surgical specimen, whereas initial biopsy had suggested fibrous dysplasia. No recurrence was observed after two and a half years' surveillance. Positive diagnosis of maxillary myxoma is histological. Treatment is primarily surgical. Strict long-term surveillance is required because of the high risk of recurrence. Copyright © 2013. Published by Elsevier Masson SAS.

  6. Quantum mechanics a paradigms approach

    CERN Document Server

    McIntyre, David H; Tate, Janet

    2012-01-01

    This innovative new text presents quantum mechanics in a manner that directly reflects the methods used in modern physics research—making the material more approachable and preparing students more thoroughly for real research. Most texts in this area start with a bit of history and then move directly to wave-particle problems with accompanying heavy mathematical analysis; Quantum Mechanics provides a foundation in experimental phenomena and uses a more approachable, less intimidating, more powerful mathematical matrix model. Beginning with the Stern-Gerlach experiments and the discussion of spin measurements, and using bra-ket notation, the authors introduce an important notational system that is used throughout quantum mechanics. This non-traditional presentation is designed to enhance students’ understanding and strengthen their intuitive grasp of the subject.

  7. Gastric Adenocarcinoma: A Multimodal Approach

    Directory of Open Access Journals (Sweden)

    Humair S. Quadri

    2017-08-01

    Full Text Available Despite its declining incidence, gastric cancer (GC remains a leading cause of cancer-related deaths worldwide. A multimodal approach to GC is critical to ensure optimal patient outcomes. Pretherapy fine resolution contrast-enhanced cross-sectional imaging, endoscopic ultrasound and staging laparoscopy play an important role in patients with newly diagnosed ostensibly operable GC to avoid unnecessary non-therapeutic laparotomies. Currently, margin negative gastrectomy and adequate lymphadenectomy performed at high volume hospitals remain the backbone of GC treatment. Importantly, adequate GC surgery should be integrated in the setting of a multimodal treatment approach. Treatment for advanced GC continues to expand with the emergence of additional lines of systemic and targeted therapies.

  8. 'Academic literacies approaches to genre'?

    Directory of Open Access Journals (Sweden)

    Brian Street

    Full Text Available I provide an overview of approaches to writing referred to as 'academic literacies' building on broader traditions, such as New Literacy Studies, and I draw out the relevance of such traditions for the ways in which lecturers provide support to their students with regard to the writing requirements of the University. I offer three case studies of the application of academic literacies approaches to programmes concerned with supporting student writing, in the UK and the USA. I briefly conclude by asking how far these accounts and this work can be seen to bring together many of the themes raised at SIGET conferences - including academic literacies and its relation to genre theories - and express the hope that it opens up trajectories for future research and collaboration of the kind they were founded to develop.

  9. NEW APPROACHES TO EXPORT COMPETITIVENESS

    Directory of Open Access Journals (Sweden)

    Alina Petronela NEGREA

    2015-04-01

    Full Text Available The economic literature and the political discourse typically look at international competitiveness mainly by the means of export market shares. However, globalisation, production fragmentation and the growing importance of global value chains (GVCs increasingly challenge traditional approaches of export competitiveness and call for a more accurate and disaggregated level of analysis. Due to the growing fragmentation of production, a country exports now include a significant amount of imports of intermediate goods which are part of the export value. In this case, a simple analysis of the evolution of exports can distort the international competitive position of a country. The article suggests a new approach based on the value-added content of international trade measured by means of global value chain analysis.

  10. Intelligent Control Approaches for UAVs

    Science.gov (United States)

    KrisnaKumar, Kalmanje

    2003-01-01

    This talk will present overviews of various intelligent control technologies currently being developed and studied at the NASA Ames Research Center as applicable to Unmanned Aerial Vehicles (UAVs), Mars flyers, and to the next generation of flight controllers for manned aircraft. The approaches being examined include: (a) direct adaptive dynamic inverse controller, (b) adaptive critic-based optimal trajectory generator; (c) optimal allocation technique based on linear programming; (4) immunized maneuvering using autopilot building blocks. These approaches can utilize, but do not require, fault detection and isolation information. Piloted and unmanned simulation studies are performed to examine if the intelligent flight control techniques adequately: 1) match flying qualities of modem fly-by-wire flight controllers under nominal conditions; 2) improve performance under failure conditions when sufficient control authority is available; and 3) achieve intelligent maneuvering capabilities for unmanned vehicles. Results obtained so far will be presented and discussed.

  11. Metric approach to quantum constraints

    International Nuclear Information System (INIS)

    Brody, Dorje C; Hughston, Lane P; Gustavsson, Anna C T

    2009-01-01

    A framework for deriving equations of motion for constrained quantum systems is introduced and a procedure for its implementation is outlined. In special cases, the proposed new method, which takes advantage of the fact that the space of pure states in quantum mechanics has both a symplectic structure and a metric structure, reduces to a quantum analogue of the Dirac theory of constraints in classical mechanics. Explicit examples involving spin-1/2 particles are worked out in detail: in the first example, our approach coincides with a quantum version of the Dirac formalism, while the second example illustrates how a situation that cannot be treated by Dirac's approach can nevertheless be dealt with in the present scheme.

  12. CONCEPTS AND APPROACHES FOR THE ...

    Science.gov (United States)

    This document is intended to assist users in establishing or refining protocols, including the specific methods related to field sampling, laboratory sample processing, taxonomy, data entry, management and analysis, and final assessment and reporting. It also reviews and provides information on development of monitoring designs to address certain types of environmental questions and approaches for documenting and reporting data quality and performance characteristics for large river biological monitoring. The approaches presented are not intended to replace existing program components but may in some cases be useful for refining them. The goal of this research is to develop methods and indicators that are useful for evaluating the condition of aquatic communities, for assessing the restoration of aquatic communities in response to mitigation and best management practices, and for determining the exposure of aquatic communities to different classes of stressors (i.e., pesticides, sedimentation, habitat alteration).

  13. Variational approach in transport theory

    Energy Technology Data Exchange (ETDEWEB)

    Panta Pazos, R. [Nucler Engineering Department, UFRGS, Porto-Alegre (Brazil); Tullio de Vilhena, M. [Institute of Mathematics, UFRGS, Porto-Alegre (Brazil)

    2004-07-01

    In this work we present a variational approach to some methods to solve transport problems of neutral particles. We consider a convex domain X (for example the geometry of a slab, or a convex set in the plane, or a convex bounded set in the space) and we use discrete ordinates quadrature to get a system of differential equations derived from the neutron transport equation. The boundary conditions are vacuum for a subset of the boundary, and of specular reflection for the complementary subset of the boundary. Recently some different approximation methods have been presented to solve these transport problems. We introduce in this work the adjoint equations and the conjugate functions obtained by means of the variational approach. First we consider the general formulation, and then some numerical methods such as spherical harmonics and spectral collocation method. (authors)

  14. Novel approaches to epilepsy treatment

    DEFF Research Database (Denmark)

    Sørensen, Andreas T; Kokaia, Merab

    2013-01-01

    The aim of epilepsy treatment is to achieve complete seizure freedom. Nonetheless, numerous side effects and seizure resistance to antiepileptic drugs (AEDs) affecting about 30-40% of all patients are main unmet needs in today's epileptology. For this reason, novel approaches to treat epilepsy...... are highly needed. Herein, we highlight recent progress in stem-cell-based and gene transfer-based therapies in epilepsy according to findings in animal models and address their potential clinical application. Multiple therapeutic targets are described, including neuropeptides, neurotrophic factors......, and inhibitory neurotransmitters. We also address new molecular-genetic approaches utilizing optogenetic technology. The therapeutic strategies presented herein are predominately aimed toward treatment of partial/focal epilepsies, but could also be envisaged for targeting key seizure propagation areas...

  15. A Hamiltonian approach to Thermodynamics

    International Nuclear Information System (INIS)

    Baldiotti, M.C.; Fresneda, R.; Molina, C.

    2016-01-01

    In the present work we develop a strictly Hamiltonian approach to Thermodynamics. A thermodynamic description based on symplectic geometry is introduced, where all thermodynamic processes can be described within the framework of Analytic Mechanics. Our proposal is constructed on top of a usual symplectic manifold, where phase space is even dimensional and one has well-defined Poisson brackets. The main idea is the introduction of an extended phase space where thermodynamic equations of state are realized as constraints. We are then able to apply the canonical transformation toolkit to thermodynamic problems. Throughout this development, Dirac’s theory of constrained systems is extensively used. To illustrate the formalism, we consider paradigmatic examples, namely, the ideal, van der Waals and Clausius gases. - Highlights: • A strictly Hamiltonian approach to Thermodynamics is proposed. • Dirac’s theory of constrained systems is extensively used. • Thermodynamic equations of state are realized as constraints. • Thermodynamic potentials are related by canonical transformations.

  16. Nanorobotics current approaches and techniques

    CERN Document Server

    Ferreira, Antoine

    2013-01-01

    Nanorobot devices now perform a wide variety of tasks at the nanoscale in a wide variety of fields including but not limited to fields such as manufacturing, medicine, supply chain, biology, and outer space. Nanorobotics: Current Approaches and Techniques is a comprehensive overview of this interdisciplinary field with a wide ranging discussion that includes nano-manipulation and industrial nanorobotics, nanorobotics in biology and medicine, nanorobotic sensing, navigation and swarm behavior, and protein and DNA-based nanorobotics. Also included is the latest on topics such as bio-nano-actuators and propulsion and navigation of nanorobotic systems using magnetic fields. Nanorobotics: Current Approaches and Techniques is an ideal book for scientists, researchers, and engineers actively involved in applied and robotic research and development.

  17. A Hamiltonian approach to Thermodynamics

    Energy Technology Data Exchange (ETDEWEB)

    Baldiotti, M.C., E-mail: baldiotti@uel.br [Departamento de Física, Universidade Estadual de Londrina, 86051-990, Londrina-PR (Brazil); Fresneda, R., E-mail: rodrigo.fresneda@ufabc.edu.br [Universidade Federal do ABC, Av. dos Estados 5001, 09210-580, Santo André-SP (Brazil); Molina, C., E-mail: cmolina@usp.br [Escola de Artes, Ciências e Humanidades, Universidade de São Paulo, Av. Arlindo Bettio 1000, CEP 03828-000, São Paulo-SP (Brazil)

    2016-10-15

    In the present work we develop a strictly Hamiltonian approach to Thermodynamics. A thermodynamic description based on symplectic geometry is introduced, where all thermodynamic processes can be described within the framework of Analytic Mechanics. Our proposal is constructed on top of a usual symplectic manifold, where phase space is even dimensional and one has well-defined Poisson brackets. The main idea is the introduction of an extended phase space where thermodynamic equations of state are realized as constraints. We are then able to apply the canonical transformation toolkit to thermodynamic problems. Throughout this development, Dirac’s theory of constrained systems is extensively used. To illustrate the formalism, we consider paradigmatic examples, namely, the ideal, van der Waals and Clausius gases. - Highlights: • A strictly Hamiltonian approach to Thermodynamics is proposed. • Dirac’s theory of constrained systems is extensively used. • Thermodynamic equations of state are realized as constraints. • Thermodynamic potentials are related by canonical transformations.

  18. Sociocultural epidemiology: an essential approach.

    Directory of Open Access Journals (Sweden)

    Paul Hersch-Martínez

    2013-09-01

    Full Text Available The necessity of an inclusive epidemiological approach, capable to attend the diverse dimensions involved in health damage as a reflective phenomenon of society is analyzed. The range of perspectives involved requires an inclusive methodological scope and applicative channels, in order to deal with sanitary realities systematically related to culture and social organization. Some constitutive elements of sociocultural epidemiology are underlined, shaping an operative proposal that can enhance the relationship between disciplines and sectors regarding specific outstanding public health problems.

  19. An efficient iris segmentation approach

    Science.gov (United States)

    Gomai, Abdu; El-Zaart, A.; Mathkour, H.

    2011-10-01

    Iris recognition system became a reliable system for authentication and verification tasks. It consists of five stages: image acquisition, iris segmentation, iris normalization, feature encoding, and feature matching. Iris segmentation stage is one of the most important stages. It plays an essential role to locate the iris efficiently and accurately. In this paper, we present a new approach for iris segmentation using image processing technique. This approach is composed of four main parts. (1) Eliminating reflections of light on the eye image based on inverting the color of the grayscale image, filling holes in the intensity image, and inverting the color of the intensity image to get the original grayscale image without any reflections. (2) Pupil boundary detection based on dividing an eye image to nine sub-images and finding the minimum value of the mean intensity for each sub-image to get a suitable threshold value of pupil. (3) Enhancing the contrast of outer iris boundary using exponential operator to have sharp variation. (4) Outer iris boundary localization based on applying a gray threshold and morphological operations on the rectangular part of an eye image including the pupil and the outer boundaries of iris to find the small radius of outer iris boundary from the center of pupil. The proposed approach has been tested on CASIA v1.0 iris image database and other collected iris image database. The experimental results show that the approach is able to detect pupil and outer iris boundary with high accuracy results approximately 100% and reduce time consuming.

  20. [A sociological approach to vulnerability].

    Science.gov (United States)

    Pelège, Patrick

    2012-01-01

    The term precarity covers many realities. It has become one of those "portmanteau words" which, as a resuIt of being constantly reassessed, is losing its meaning. In order to avoid an overly sectional approach to the mechanisms of social precarity, or exclusion, it is necessary to understand in more general terms the sociological processes around the concept of the social tie and its effects of rupture.

  1. An automatic image recognition approach

    Directory of Open Access Journals (Sweden)

    Tudor Barbu

    2007-07-01

    Full Text Available Our paper focuses on the graphical analysis domain. We propose an automatic image recognition technique. This approach consists of two main pattern recognition steps. First, it performs an image feature extraction operation on an input image set, using statistical dispersion features. Then, an unsupervised classification process is performed on the previously obtained graphical feature vectors. An automatic region-growing based clustering procedure is proposed and utilized in the classification stage.

  2. Approaching work and learning indirectly

    OpenAIRE

    Macintyre, Ronald; Thomson, Joan

    2013-01-01

    This paper approaches work and learning indirectly. It is part of a mixed method longitudinal study that looks at the articulation from Higher National (HN) to part time Higher Education (HE). Since 2003 the Open University in Scotland (OU) has been collecting quantitative and qualitative data on students who have HN qualifications. This paper looks at the experiences of those students and the central place of work in those journeys. \\ud \\ud The paper beings with a statistical overview. HN St...

  3. Accident management approach in Armenia

    International Nuclear Information System (INIS)

    Ghazaryan, K.

    1999-01-01

    In this lecture the accident management approach in Armenian NPP (ANPP) Unit 2 is described. List of BDBAs had been developed by OKB Gydropress in 1994. 13 accident sequences were included in this list. The relevant analyses had been performed in VNIIAES and the 'Guidelines on operator actions for beyond design basis accident (BDBA) management at ANPP Unit 2' had been prepared. These instructions are discussed

  4. Sociocultural epidemiology: an essential approach.

    OpenAIRE

    Paul Hersch-Martínez

    2013-01-01

    The necessity of an inclusive epidemiological approach, capable to attend the diverse dimensions involved in health damage as a reflective phenomenon of society is analyzed. The range of perspectives involved requires an inclusive methodological scope and applicative channels, in order to deal with sanitary realities systematically related to culture and social organization. Some constitutive elements of sociocultural epidemiology are underlined, shaping an operative proposal that can enhance...

  5. APPROACHES ON THE COMPETITIVE INTELLIGENCE

    OpenAIRE

    Ioan PETRIªOR; Natalia Ana STRÃIN (SILAS)

    2013-01-01

    Within this study, we approached the concept of "competitive intelligence" (CI), which we consider a key element for the success of a business, especially in the current period, characterized by numerous economic and financial turbulence. According to Society of Competitive Intelligence (SCIP), competitive intelligence is defined as a method of ethical and moral collection, analysis and dissemination of information regarding the competitive environment, opportunities, vulnerabilities, and int...

  6. MODERN APPROACH TOWARDS IMMUNOMODULATION THERAPY

    Directory of Open Access Journals (Sweden)

    L. S. Namazova-Baranova

    2012-01-01

    Full Text Available This article covers one of the most discussed issues of clinical immunology — the role of dendritic cells in acquired immunity. Modern conception of dendritic cells participating in antigen handling procedure and its presentation, interaction with other immune cells made it possible to change approach towards immunomodulating therapy dramatically and to develop a new class of immunostimulants, that influence simultaneously cell and humoral immunity both in loci of antigen intervention on the mucosal level and systemically.

  7. Review og pattern matching approaches

    DEFF Research Database (Denmark)

    Manfaat, D.; Duffy, Alex; Lee, B. S.

    1996-01-01

    This paper presents a review of pattern matching techniques. The application areas for pattern matching are extensive, ranging from CAD systems to chemical analysis and from manufacturing to image processing. Published techniques and methods are classified and assessed within the context of three...... key issues: pattern classes, similiarity types and mathing methods. It has been shown that the techniques and approaches are as diverse and varied as the applications....

  8. Ares I Integrated Test Approach

    Science.gov (United States)

    Taylor, Jim

    2008-01-01

    This slide presentation reviews the testing approach that NASA is developing for the Ares I launch vehicle. NASA is planning a complete series of development, qualification and verification tests. These include: (1) Upper stage engine sea-level and altitude testing (2) First stage development and qualification motors (3) Upper stage structural and thermal development and qualification test articles (4) Main Propulsion Test Article (MPTA) (5) Upper stage green run testing (6) Integrated Vehicle Ground Vibration Testing (IVGVT) and (7) Aerodynamic characterization testing.

  9. NEW APPROACHES TO EXPORT COMPETITIVENESS

    OpenAIRE

    Alina Petronela NEGREA

    2015-01-01

    The economic literature and the political discourse typically look at international competitiveness mainly by the means of export market shares. However, globalisation, production fragmentation and the growing importance of global value chains (GVCs) increasingly challenge traditional approaches of export competitiveness and call for a more accurate and disaggregated level of analysis. Due to the growing fragmentation of production, a country exports now include a significant amount of import...

  10. HEALTHCARE MARKETING - A RELATIONAL APPROACH

    OpenAIRE

    CAZACU Lavinia; OPRESCU Alina Elena

    2015-01-01

    This paper aims to identify the unique characteristics of healthcare services, the challenges faced in the implementation of marketing principles into the healthcare services sector and also the behavior tendencies of the healthcare consumer. Taking into account the differences between healthcare services and other services and the importance of the doctor-patient relationship, a new marketing approach seems to be a solution for all problems and a response for all unanswered questions. A revi...

  11. Nonlinear approach to ternary scission

    CERN Document Server

    Kartavenco, V G

    2002-01-01

    Description of three-center configuration within mean-field approaches meets uncertainties to select a peculiar set of constraints. We suggest to use the inverse mean field method to solve single-particle Schroedinger equation, instead of constrained selfconsistent Hartree-Fock equations. It is shown, that it is possible to simulate one-dimensional three-center system in the approximation of reflectless single- particle potentials (authors)

  12. Architecture Approach in System Development

    Directory of Open Access Journals (Sweden)

    Ladislav Burita

    2017-01-01

    Full Text Available The purpose of this paper is to describe a practical solution of architecture approach in system development. The software application is the system which optimizes the transport service. The first part of the paper defines the enterprise architecture, its parts and frameworks. Next is explained the NATO Architecture Framework (NAF, a tool for command and control systems development in military environment. The NAF is used for architecture design of the system for optimization of the transport service.

  13. Approach and Landing Test emblem

    Science.gov (United States)

    1976-01-01

    This circular, red, white, and blue emblem has been chosen as the Official insignia for the Space Shuttle Approach and Landing Test (ALT) flights. A picture of the Orbiter 101 'Enterprise' is superimposed over a red triangle, which in turn is superimposed over a large inner circle of dark blue. The surnames of the members of the two ALT crews are in white in the field of blue.

  14. A possibilistic approach to clustering

    Science.gov (United States)

    Krishnapuram, Raghu; Keller, James M.

    1993-01-01

    Fuzzy clustering has been shown to be advantageous over crisp (or traditional) clustering methods in that total commitment of a vector to a given class is not required at each image pattern recognition iteration. Recently fuzzy clustering methods have shown spectacular ability to detect not only hypervolume clusters, but also clusters which are actually 'thin shells', i.e., curves and surfaces. Most analytic fuzzy clustering approaches are derived from the 'Fuzzy C-Means' (FCM) algorithm. The FCM uses the probabilistic constraint that the memberships of a data point across classes sum to one. This constraint was used to generate the membership update equations for an iterative algorithm. Recently, we cast the clustering problem into the framework of possibility theory using an approach in which the resulting partition of the data can be interpreted as a possibilistic partition, and the membership values may be interpreted as degrees of possibility of the points belonging to the classes. We show the ability of this approach to detect linear and quartic curves in the presence of considerable noise.

  15. System Approach in RIPRAN Method

    Directory of Open Access Journals (Sweden)

    Branislav Lacko

    2017-06-01

    Full Text Available The article describes reasons, principles for design, structure and using of RIPRAN method (Risk Project Analysis for risk project analysis. The RIPRAN method is used to identify, quantify risks, and design proposals that reduce risk in the project to increase the likelihood of successful completion of the project. The method uses a system and process approach to risk analysis and respects international ISO standards that recommend how to perform a high‑quality risk analysis of the project. The method has been incorporated into the national standard of the Czech Republic among the recommended knowledge for certified project managers. The third version of the method is available. The method is included in teaching at many universities in the Czech Republic, trained by a number of training firms and used by firms to analyse the risks of corporate projects or by various risk analysis institutions for projects funded by the EU structural funds. The aim of the article is to inform about the RIPRAN method. At the same time, the paper points out that the method describes the procedure for risk analysis of the project and presents the benefits of RIPRAN application. The description of a system approach application when designing the RIPRAN method serves as an example of a system approach to risk engineering.

  16. Technical approach to groundwater restoration

    International Nuclear Information System (INIS)

    1993-01-01

    The Technical Approach to Groundwater Restoration (TAGR) provides general technical guidance to implement the groundwater restoration phase of the Uranium Mill Tailings Remedial Action (UMTRA) Project. The TAGR includes a brief overview of the surface remediation and groundwater restoration phases of the UMTRA Project and describes the regulatory requirements, the National Environmental Policy Act (NEPA) process, and regulatory compliance. A section on program strategy discusses program optimization, the role of risk assessment, the observational approach, strategies for meeting groundwater cleanup standards, and remedial action decision-making. A section on data requirements for groundwater restoration evaluates the data quality objectives (DQO) and minimum data required to implement the options and comply with the standards. A section on sits implementation explores the development of a conceptual site model, approaches to site characterization, development of remedial action alternatives, selection of the groundwater restoration method, and remedial design and implementation in the context of site-specific documentation in the site observational work plan (SOWP) and the remedial action plan (RAP). Finally, the TAGR elaborates on groundwater monitoring necessary to evaluate compliance with the groundwater cleanup standards and protection of human health and the environment, and outlines licensing procedures

  17. Systems approach in energy management

    International Nuclear Information System (INIS)

    Dutta-Choudhury, K.

    1993-01-01

    Several years ago when the author was working in the chemicals division of a paper company in Instrumentation and Controls, one experience had a lasting impact on his work approach which is systems approach. The maintenance manager told the author that a very important piece of boiler instrument of the power plant had broken down and delivery of the replacement needed to be expedited. The instrument was ordered over the phone in another city. The purchase order was personally delivered at the supplier's office and arrangements were made so the instrument was put on the next flight. A week later the maintenance manager indicated that the particular instrument still had not arrived in the plant and he could not run the power plant. Thus the company incurred substantial losses. Further inquiries showed that the instrument did indeed arrive at the plant stores on time. But, in the absence of any instructions thereon, the instrument was not delivered to the power plant. The sense of urgency was lost in the existing delivery process. In other words, the process or system failed. The whole process from requisitioning to delivery of ordered items was analyzed and corrective procedures were incorporated to prevent future repetitions. This brings up the subject of systems approach in engineering management in general and energy management in particular. This involves defining an objective and designing a system for an effective way of getting there

  18. Security Management – Systems Approach

    Directory of Open Access Journals (Sweden)

    Milan Kný

    2015-12-01

    Full Text Available The aim of the contribution is the use of the systems approach to treat security management as a practical field and new scientific discipline. The philosophy of systems approach to the solution of problems generally is an adequate methodological basis even for the theory of management. The path to the real optimization of security situation leads only through the holistic and solid solution. Applications of systems analysis and synthesis back up the fact, that systems approach and systems thinking should not absent in security objects. The truthfulness of the claim, that security management is a well-established discipline, depends on ongoing discussion that represents useful process of development of new scientific discipline. At the same time the rationality of science and systematism works as a counterbalance to irrational fear of the whole society, too. Which questions of security remain open in relation to „our interests“? Current problems of Europe should be solved systematically. It is necessary to define the space of interest (territorially the border of the EU or the Schengen area, to implement the system to the object with respect to the borders of the space, to specify the structure and subjects of decision making and implementation.

  19. Home hygiene: a risk approach.

    Science.gov (United States)

    Bloomfield, Sally F

    2003-01-01

    The need to place "prevention through hygiene" at the core of strategies for infection prevention has been emphasised by recent events. Indications are that re-evaluation of current practice and the promotion of improved hygiene in the domestic setting could have a significant impact in reducing infectious disease. If the public are to play a part however they must be properly informed. Encouraging the concept of the home as a setting in which the whole range of activities occur, including food hygiene, personal hygiene and hygiene related to medical care, provides the opportunity for a rational approach to home hygiene based on risk assessment. In the home surfaces (including hand surfaces) and other sites play an important part in the transmission of infection, especially food-borne infections. From an assessment of the frequency of occurrence of pathogens and potential pathogens at reservoirs, disseminators and hand and food contact sites together with the potential for transfer within the home, the risks of exposure can be assessed. This can be used to develop a rational approach in which effective hygiene procedures involving cleaning and disinfection as appropriate are targeted at these sites to reduce risks of cross contamination. This approach is consistent with the view that good home hygiene is not about "getting rid of household germs" but about targeting hygiene measures appropriately to reduce exposure to germs and thereby prevent cross infection. In motivating change, education programmes must take account of concerns related to antimicrobial resistance, the environment and the "health" of the immune system.

  20. Nonpharmaceutical approaches to pain management.

    Science.gov (United States)

    Corti, Lisa

    2014-03-01

    A nonpharmaceutical approach to managing pain is one that does not employ a medication. The use of such approaches, in conjunction with pharmaceuticals as part of multimodal methods to managing pain, is becoming more popular as evidence is emerging to support their use. Cold therapy, for one, is used to reduce the inflammation and tissue damage seen in acute injuries and can be very effective at reducing acute pain. Incorporating the use of superficial heat therapy when treating pain associated with chronic musculoskeletal conditions is often employed as heat increases blood flow, oxygen delivery, and tissue extensibility. Acupuncture is gaining acceptance in veterinary medicine. Research is confirming that release of endogenous endorphins and enkephalins from the application of needles at specific points around the body can effectively control acute and chronic pain. The use of 2 newer therapies-extracorporeal shockwave therapy and platelet-rich plasma-represent an attempt to eliminate the causes of pain at the tissue level by promoting tissue healing and regeneration. Reviewed in this article, these therapies are intended to be used in conjunction with pharmaceuticals as part of a multimodal approach to pain management. Copyright © 2014 Elsevier Inc. All rights reserved.

  1. Ecosystem approaches to human health

    Directory of Open Access Journals (Sweden)

    Nielsen N. Ole

    2001-01-01

    Full Text Available The promotion of human health must be embedded in the wider pursuit of ecosystem health. Interventions will be impaired if ecosystem-linked determinants of health are not taken into account. In the extreme case, if ecosystems lose their capacity for renewal, society will lose life support services. Essential features of ecosystem health are the capacity to maintain integrity and to achieve reasonable and sustainable human goals. An ecosystem approach to research and management must be transdisciplinary and assure participation of stakeholders. These requisites provide a means for science to better deal with the complexity of ecosystems, and for policy-makers and managers to establish and achieve reasonable societal goals. The ecosystem approach can determine links between human health and activities or events which disturb ecosystem state and function. Examples are: landscape disturbance in agriculture, mining, forestry, urbanization, and natural disasters. An understanding of these links can provide guidance for management interventions and policy options that promote human health. An ecosystem approach to management must be adaptive because of irreducible uncertainty in ecosystem function.

  2. An abstract approach to music.

    Energy Technology Data Exchange (ETDEWEB)

    Kaper, H. G.; Tipei, S.

    1999-04-19

    In this article we have outlined a formal framework for an abstract approach to music and music composition. The model is formulated in terms of objects that have attributes, obey relationships, and are subject to certain well-defined operations. The motivation for this approach uses traditional terms and concepts of music theory, but the approach itself is formal and uses the language of mathematics. The universal object is an audio wave; partials, sounds, and compositions are special objects, which are placed in a hierarchical order based on time scales. The objects have both static and dynamic attributes. When we realize a composition, we assign values to each of its attributes: a (scalar) value to a static attribute, an envelope and a size to a dynamic attribute. A composition is then a trajectory in the space of aural events, and the complex audio wave is its formal representation. Sounds are fibers in the space of aural events, from which the composer weaves the trajectory of a composition. Each sound object in turn is made up of partials, which are the elementary building blocks of any music composition. The partials evolve on the fastest time scale in the hierarchy of partials, sounds, and compositions. The ideas outlined in this article are being implemented in a digital instrument for additive sound synthesis and in software for music composition. A demonstration of some preliminary results has been submitted by the authors for presentation at the conference.

  3. On Approach: Jupiter and Io

    Science.gov (United States)

    2007-01-01

    [figure removed for brevity, see original site] Click on the image for movie of On Approach: Jupiter and Io This sequence of images was taken on Jan. 8, 2007, with the New Horizons Long Range Reconnaissance Imager (LORRI), while the spacecraft was about 81 million kilometers (about 50 million miles) from Jupiter. Jupiter's volcanic moon Io is to the right; the planet's Great Red Spot is also visible. The image was one of 11 taken during the Jan. 8 approach sequence, which signaled the opening of the New Horizons Jupiter encounter. Even in these early approach images, Jupiter shows different face than what previous visiting spacecraft -- such as Voyager 1, Galileo and Cassini -- have seen. Regions around the equator and in the southern tropical latitudes seem remarkably calm, even in the typically turbulent 'wake' behind the Great Red Spot. The New Horizons science team will scrutinize these major meteorological features -- including the unexpectedly calm regions -- to understand the diverse variety of dynamical processes on the solar system's largest planet. These include the newly formed Little Red Spot, the Great Red Spot and a variety of zonal features.

  4. [Narrative Approach to Moral Development.] Commentary.

    Science.gov (United States)

    Lapsley, Daniel K.

    1996-01-01

    Elaborates on some issues in the debate between Kohlberg's cognitive-developmental approach and a narrative, relativistic, approach to studies of moral development. Reviews the concept of self in both approaches, ideas on the Cartesian rationality underlying Kohlberg's theories, and the reliance of the self on language in narrative approaches.…

  5. Comparison of Two Approaches to Approximated Reasoning

    NARCIS (Netherlands)

    van den Broek, P.M.; Wagenknecht, Michael; Hampel, Rainer

    A comparison is made of two approaches to approximate reasoning: Mamdani's interpolation method and the implication method. Both approaches are variants of Zadeh's compositional rule of inference. It is shown that the approaches are not equivalent. A correspondence between the approaches is

  6. Fuzzy multiple linear regression: A computational approach

    Science.gov (United States)

    Juang, C. H.; Huang, X. H.; Fleming, J. W.

    1992-01-01

    This paper presents a new computational approach for performing fuzzy regression. In contrast to Bardossy's approach, the new approach, while dealing with fuzzy variables, closely follows the conventional regression technique. In this approach, treatment of fuzzy input is more 'computational' than 'symbolic.' The following sections first outline the formulation of the new approach, then deal with the implementation and computational scheme, and this is followed by examples to illustrate the new procedure.

  7. Surgical approaches for total hip arthroplasty

    Directory of Open Access Journals (Sweden)

    Vincent M Moretti

    2017-01-01

    Full Text Available Total hip arthroplasty (THA has become one of the most reliable and patient-requested surgical interventions in all medicine. The procedure can be performed using a variety of surgical approaches, but the posterior approach, direct lateral approach, and direct anterior approach are by far the most common across the globe. This article highlights the history and technique for each of these common approaches. A review of outcomes and complications for each approach are also provided. Each approach has its own unique advantages and disadvantages, but all can be safely and successful utilized for THA. Strong, convincing, high-quality studies comparing the different approaches are lacking at this time. Surgeons are therefore recommended to choose whichever approach they are most comfortable and experienced using. Though not described here, THA can also be done using the anterolateral approach (also known as the Watson Jones approach as well as the two-incision approach. In addition, recently, some surgeons are utilizing the so-called direct superior approach for THA. While these approaches are far less commonly utilized, they are recognized as viable alternatives to traditional approaches.

  8. The calculus a genetic approach

    CERN Document Server

    Toeplitz, Otto

    2007-01-01

    When first published posthumously in 1963, this book presented a radically different approach to the teaching of calculus.  In sharp contrast to the methods of his time, Otto Toeplitz did not teach calculus as a static system of techniques and facts to be memorized. Instead, he drew on his knowledge of the history of mathematics and presented calculus as an organic evolution of ideas beginning with the discoveries of Greek scholars, such as Archimedes, Pythagoras, and Euclid, and developing through the centuries in the work of Kepler, Galileo, Fermat, Newton, and Leibniz. Through this unique a

  9. Operational gaming an international approach

    CERN Document Server

    Ståhl, Ingolf

    1983-01-01

    Operational Gaming: An International Approach focuses on various research on this method of systems analysis. The text points out the value of this method in decision making, planning, and in the implementation of policies. The book presents a survey that highlights the connection of experimental gaming, game theory, and operational gaming. The value of gaming as a balancing method in assessing multifaceted computer models, most notably about their assumptions on human behavior, is noted. The book also offers an overview of gaming in other countries, such as Bulgaria, Soviet Union, and Japan,

  10. Computational approaches to energy materials

    CERN Document Server

    Catlow, Richard; Walsh, Aron

    2013-01-01

    The development of materials for clean and efficient energy generation and storage is one of the most rapidly developing, multi-disciplinary areas of contemporary science, driven primarily by concerns over global warming, diminishing fossil-fuel reserves, the need for energy security, and increasing consumer demand for portable electronics. Computational methods are now an integral and indispensable part of the materials characterisation and development process.   Computational Approaches to Energy Materials presents a detailed survey of current computational techniques for the

  11. Cognitive reasoning a formal approach

    CERN Document Server

    Anshakov, Oleg M

    2010-01-01

    Dealing with uncertainty, moving from ignorance to knowledge, is the focus of cognitive processes. Understanding these processes and modelling, designing, and building artificial cognitive systems have long been challenging research problems. This book describes the theory and methodology of a new, scientifically well-founded general approach, and its realization in the form of intelligent systems applicable in disciplines ranging from social sciences, such as cognitive science and sociology, through natural sciences, such as life sciences and chemistry, to applied sciences, such as medicine,

  12. Integrated Approach to Competitive Advantage

    Directory of Open Access Journals (Sweden)

    Edita Ragelskaja

    2011-07-01

    Full Text Available Environmental changes and globalization of markets make an impact on intense competition in almost all business sectors. Evolutionary changes influence companies to learn, adequately react, adapt to environmental changes and to change themselves. Such a situation has revealed the problems of competitive advan­tage of industry companies. Therefore the focus to the factors impacting competitive advantage is seen as timely and relevant. The authors of the paper analyze approaches to competitive advantage and the factors impacting competitive advantage. The integrated model of competitive advantage is proposed in the paper.Article in Lithuanian

  13. 'Lean' approach gives greater efficiency.

    Science.gov (United States)

    Call, Roger

    2014-02-01

    Adapting the 'Lean' methodologies used for many years by many manufacturers on the production line - such as in the automotive industry - and deploying them in healthcare 'spaces' can, Roger Call, an architect at Herman Miller Healthcare in the US, argues, 'easily remedy many of the inefficiencies' found within a healthcare facility. In an article that first appeared in the September 2013 issue of The Australian Hospital Engineer, he explains how 'Lean' approaches such as the 'Toyota production system', and 'Six Sigma', can be harnessed to good effect in the healthcare sphere.

  14. Gene Therapy Approaches to Hemoglobinopathies.

    Science.gov (United States)

    Ferrari, Giuliana; Cavazzana, Marina; Mavilio, Fulvio

    2017-10-01

    Gene therapy for hemoglobinopathies is currently based on transplantation of autologous hematopoietic stem cells genetically modified with a lentiviral vector expressing a globin gene under the control of globin transcriptional regulatory elements. Preclinical and early clinical studies showed the safety and potential efficacy of this therapeutic approach as well as the hurdles still limiting its general application. In addition, for both beta-thalassemia and sickle cell disease, an altered bone marrow microenvironment reduces the efficiency of stem cell harvesting as well as engraftment. These hurdles need be addressed for gene therapy for hemoglobinopathies to become a clinical reality. Copyright © 2017 Elsevier Inc. All rights reserved.

  15. Real Analysis A Historical Approach

    CERN Document Server

    Stahl, Saul

    2011-01-01

    A provocative look at the tools and history of real analysis This new edition of Real Analysis: A Historical Approach continues to serve as an interesting read for students of analysis. Combining historical coverage with a superb introductory treatment, this book helps readers easily make the transition from concrete to abstract ideas. The book begins with an exciting sampling of classic and famous problems first posed by some of the greatest mathematicians of all time. Archimedes, Fermat, Newton, and Euler are each summoned in turn, illuminating the utility of infinite, power, and trigonome

  16. HEDR modeling approach: Revision 1

    International Nuclear Information System (INIS)

    Shipler, D.B.; Napier, B.A.

    1994-05-01

    This report is a revision of the previous Hanford Environmental Dose Reconstruction (HEDR) Project modeling approach report. This revised report describes the methods used in performing scoping studies and estimating final radiation doses to real and representative individuals who lived in the vicinity of the Hanford Site. The scoping studies and dose estimates pertain to various environmental pathways during various periods of time. The original report discussed the concepts under consideration in 1991. The methods for estimating dose have been refined as understanding of existing data, the scope of pathways, and the magnitudes of dose estimates were evaluated through scoping studies

  17. A psychological approach to ethics.

    Science.gov (United States)

    De Meira Penna, J O

    1985-09-01

    This article has the purpose of calling attention to C.G. Jung's archetypal concept of the Self as an approach to ethics. The distinction between simple morality and transcendent ethics is established. Comparison is made between the archetype of the Self and Kant's categorical imperative. Freud's superego, however, is assimilated to a "natural" outlook on morality, such as the notion of altruism in sociobiology. The superego is only the psychic effect of the current moral code-which could be explained either culturally or as a Lamarckian acquired characteristic of the unconscious. Jung's transcendent ethics is expressed in an "ethical mandala."

  18. Giant resonances: reaction theory approach

    International Nuclear Information System (INIS)

    Toledo Piza, A.F.R. de; Foglia, G.A.

    1989-09-01

    The study of giant resonances through the use of reaction theory approach is presented and discussed. Measurements of cross-sections to the many available decay channels following excitation of giant multipole resonances (GMR) led one to view these phenomena as complicated dynamical syndromes so that theoretical requirements for their study must be extended beyond the traditional bounds of nuclear structure models. The spectra of decay products following GMR excitation in heavy nuclei are well described by statistical model (Hauser-Feshback, HF) predictions indicated that spreading of the collective modes plays a major role in shaping exclusive cross-sections. (A.C.A.S.) [pt

  19. Computer Networks A Systems Approach

    CERN Document Server

    Peterson, Larry L

    2011-01-01

    This best-selling and classic book teaches you the key principles of computer networks with examples drawn from the real world of network and protocol design. Using the Internet as the primary example, the authors explain various protocols and networking technologies. Their systems-oriented approach encourages you to think about how individual network components fit into a larger, complex system of interactions. Whatever your perspective, whether it be that of an application developer, network administrator, or a designer of network equipment or protocols, you will come away with a "big pictur

  20. An experiential approach for innovation

    DEFF Research Database (Denmark)

    Jensen, Jesper Legaard

    2012-01-01

    , going from immaterial layers to material, with the product experience particularly present in the top layers. A benefit of using the model is that it enables a more strategic approach to innovation at different layers. The model also enables transferring experiential concepts from one product...... and assigning it to another, which can be very fruitful as a tool for innovation. I present an experiment done with a group of design students, where we used the model to analyze the experience of the Beosound 3200 stereo. We identified concepts such as the welcoming where the stereo opens by a hand gesture...

  1. HEDR modeling approach: Revision 1

    Energy Technology Data Exchange (ETDEWEB)

    Shipler, D.B.; Napier, B.A.

    1994-05-01

    This report is a revision of the previous Hanford Environmental Dose Reconstruction (HEDR) Project modeling approach report. This revised report describes the methods used in performing scoping studies and estimating final radiation doses to real and representative individuals who lived in the vicinity of the Hanford Site. The scoping studies and dose estimates pertain to various environmental pathways during various periods of time. The original report discussed the concepts under consideration in 1991. The methods for estimating dose have been refined as understanding of existing data, the scope of pathways, and the magnitudes of dose estimates were evaluated through scoping studies.

  2. Experimental design a chemometric approach

    CERN Document Server

    Deming, SN

    1987-01-01

    Now available in a paperback edition is a book which has been described as ``...an exceptionally lucid, easy-to-read presentation... would be an excellent addition to the collection of every analytical chemist. I recommend it with great enthusiasm.'' (Analytical Chemistry). Unlike most current textbooks, it approaches experimental design from the point of view of the experimenter, rather than that of the statistician. As the reviewer in `Analytical Chemistry' went on to say: ``Deming and Morgan should be given high praise for bringing the principles of experimental design to the level of the p

  3. Setup reduction approaches for machining

    Energy Technology Data Exchange (ETDEWEB)

    Gillespie, L.K.

    1997-04-01

    Rapid setup is a common improvement approach in press working operations such as blanking and shearing. It has paid major dividends in the sheet metal industry. It also has been a major improvement thrust for high-production machining operations. However, the literature does not well cover all the setup operations and constraints for job shop work. This review provides some insight into the issues involved. It highlights the floor problems and provides insights for further improvement. The report is designed to provide a quick understanding of the issues.

  4. [Medical approach to "the Quixote"].

    Science.gov (United States)

    Sánchez Granjel, Luis

    2005-01-01

    The study of the madness that turned the gentleman Alonso Quijano into the knight don Quixote, gives us no acceptable explanation about the reason of that mental disorder; this madness has already had a array of medical approaches. In order to understand it, there exist two possible factors: the repression of a sexual necessity which his nature imposed on himself, and the behaviour he was obliged to have because of his condition of gentleman; this study will try to explain and value these factors, taking also into account the information provided by the novel.

  5. Approach to Mars Field Geology

    Science.gov (United States)

    Muehlberger, William; Rice, James W.; Parker, Timothy; Lipps, Jere H.; Hoffman, Paul; Burchfiel, Clark; Brasier, Martin

    1998-01-01

    The goals of field study on Mars are nothing less than to understand the processes and history of the planet at whatever level of detail is necessary. A manned mission gives us an unprecedented opportunity to use the immense power of the human mind to comprehend Mars in extraordinary detail. To take advantage of this opportunity, it is important to examine how we should approach the field study of Mars. In this effort, we are guided by over 200 years of field exploration experience on Earth as well as six manned missions exploring the Moon.

  6. Microfluidic Approach to Cell Microencapsulation.

    Science.gov (United States)

    Sharma, Varna; Hunckler, Michael; Ramasubramanian, Melur K; Opara, Emmanuel C; Katuri, Kalyan C

    2017-01-01

    Bioartificial pancreas made of insulin-secreting islets cells holds great promise in the treatment of individuals with Type-1 diabetes. Successful islet cell microencapsulation in biopolymers is a key step for providing immunoisolation of transplanted islet cells. Because of the variability in the size and shape of pancreatic islets, one of the main obstacles in their microencapsulation is the inability to consistently control shape, size, and microstructure of the encapsulating biopolymer capsule. In this chapter, we provide a detailed description of a microfluidic approach to islet cell encapsulation in alginate that might address the microencapsulation challenges.

  7. Spontaneous regression of a giant basilar artery aneurysm in a young adult after surgical injury: case report and literature review

    International Nuclear Information System (INIS)

    Zhang He; Li Minghua; Wang Chun; Li Yongdong; Xu Tao

    2007-01-01

    A giant basilar artery aneurysm of young woman with endocrine disturbance was misdiagnosed as a large pituitary adenoma and treated surgically via a trans-sphenoidal approach was planned. But the neurosurgery was finally aborted because of massive bleeding during the procedure. One year later, a cerebral angiography confirmed this basilar artery aneurysm was obviously regressed and then endovascular coiling was successfully performed. No neurological complication occurred post-procedure and the endocrine dysfunction symptom was obviously improved. (authors)

  8. The ethnoprimatological approach in primatology.

    Science.gov (United States)

    Fuentes, Agustin; Hockings, Kimberley J

    2010-09-01

    Recent and long-term sympatries between humans and nonhuman primates (hereafter primates) are central to the behavioral ecology, conservation, and evolutionary trajectories of numerous primate species. Ethnoprimatology emphasizes that interconnections between humans and primates should be viewed as more than just disruptions of a "natural" state, and instead anthropogenic contexts must be considered as potential drivers for specific primate behavioral patterns. Rather than focusing solely on the behavior and ecology of the primate species at hand, as in traditional primatology, or on the symbolic meanings and uses of primates, as in socio-cultural anthropology, ethnoprimatology attempts to merge these perspectives into a more integrative approach. As human pressures on environments continue to increase and primate habitats become smaller and more fragmented, the need for a primatology that considers the impact of human attitudes and behavior on all aspects of primate lives and survival is imperative. In this special issue, we present both data-driven examples and more general discussions that describe how ethnoprimatological approaches can be both a contribution to the core theory and practice of primatology and a powerful tool in our goal of conservation action. 2010 Wiley-Liss, Inc.

  9. DOE systems approach and integration

    International Nuclear Information System (INIS)

    Logan, J.A.

    1987-01-01

    Six sites are now disposing of most of DOE's currently generated waste. These are: Hanford, Idaho National Engineering Laboratory, Los Alamos National Laboratory, the Nevada Test Site, Oak Ridge, and Savannah River. Within DOE, experience with disposal of solid LLW has been that arid site disposal facilities (first four) appear to have performed well, while humid site disposal facilities (last two) have experienced some waste migration. DOE's intent, of course, is to operate all its waste disposal facilities so that public health and safety are not adversely affected. To ensure that this continues to be the case, activities are underway to increase use of waste form stabilization and engineered barriers where appropriate. For the sake of overall economy, these measures are to be applied as and where needed, through use of the systems approach. In this paper the author discusses two topics: the system approach, which DOE has decided to use for resolving waste disposal problems in the management of DOE's low-level wastes; and DOE's intended integration of activities underway at the waste management systems throughout DOE facilities. 2 figures

  10. Interdisciplinary Approach in Engineering Education

    Directory of Open Access Journals (Sweden)

    Anda Zeidmane

    2011-04-01

    Full Text Available The analysis of the scientific literature available on the types of general competences and their classification caused the authors to conclude that it is necessary to implement interdisciplinary approach in engineering education to develop competences necessary for engineers to make them competitive in the labour market. The attention should be paid to a professional foreign language, computer literacy and educational psychology recommendations. To improve professional foreign language skills, CLIL (Content and Language Integrated Learning method should be integrated in the study process of engineering education. In order to develop information literacy competence, it is important to create a single e-study environment. The academic staff, developing study subjects for engineering programmes, should focus on the study content and study methods. As regards the content, the compromise should be sought between fundamental acquisition of the knowledge of the subject matter, the know-how of the application of this knowledge as well as the use of brand new software in the calculations. The paper presents the examples of the application of the interdisciplinary approach in the universities, where the authors of the paper are affiliated: the LUA (Latvia University of Agriculture and the RTU (Riga Technical University, respectively.

  11. Environmental education and indigenous approach

    International Nuclear Information System (INIS)

    Babar, S.M.; Hussain, M.; Mahmood, T.

    2005-01-01

    Environmental pollution control is the most important and highly discussed issue at the international level. Our and our's next generation survival highly depends on environment. Environmental security is not less important than territorial security. Living in the Competitive trade, Business and Commerce era. WTO threats of globalization to countries like Pakistan require sharp and immediate actions. SOS(Save our Sole) steps should be taken in Environmental Education in order to reorganizing values and clarifying Concepts to develop the necessary skills and attitude necessary to understand and appreciate the interrelatidness among masses, the Cultures and Ecosystem. Historical backgrounds along with different approaches were discussed particularly reference to Pakistan. In this presentation a new but indigenous idea is flashed to improve the environment education system in poor third world countries including Pakistan. Instead of imported ideas, previous implemented as such, indigenous approach highly Perfumed with Islamic, Ideological and cultural blends will do the right job in right direction if employed with true sense of commitment. (author)

  12. Molecular Approaches to Studying Denitrification

    Science.gov (United States)

    Voytek, M. A.

    2001-05-01

    Denitrification is carried out by a diverse array of microbes, mainly as an alternative mode of respiration that allows the organisms to respire using oxidized N compounds instead of oxygen. A common approach in biogeochemistry to the study of the regulation of denitrification is to assess activity by mass balance of substrates and products or direct rate measurements and has intrinsically assumed resource regulation of denitrification. Reported rates can vary significantly even among ecosystems characterized by similar environmental conditions, thus indicating that direct control by abiotic factors often is not sufficient to predict denitrification rates accurately in natural environments. Alternatively, a microbiological approach would proceed with the identification of the organisms responsible and an evaluation of the effect of environmental factors on the biochemical pathways involved. Traditional studies have relied on culturing techniques, such as most probable number enrichments, and have failed to assess the role of the predominately uncultivable members of the microbial community. A combination of biogeochemical measurements and the assessment of the microbial community is necessary and becoming increasingly possible with the development and application of molecular techniques. In order to understand how the composition and physiological behavior of the microbial community affects denitrification rates, we use a suite of molecular techniques developed for phylogenetic and metabolic characterization of denitrifying communities. Molecular tools available for quantifying denitrifying bacteria and assessing their diversity and activity are summarized. Their application is illustrated with examples from marine and freshwater environments. Emerging techniques and their application to ground water studies will be discussed.

  13. Approach to Rectal Cancer Surgery

    Directory of Open Access Journals (Sweden)

    Terence C. Chua

    2012-01-01

    Full Text Available Rectal cancer is a distinct subset of colorectal cancer where specialized disease-specific management of the primary tumor is required. There have been significant developments in rectal cancer surgery at all stages of disease in particular the introduction of local excision strategies for preinvasive and early cancers, standardized total mesorectal excision for resectable cancers incorporating preoperative short- or long-course chemoradiation to the multimodality sequencing of treatment. Laparoscopic surgery is also increasingly being adopted as the standard rectal cancer surgery approach following expertise of colorectal surgeons in minimally invasive surgery gained from laparoscopic colon resections. In locally advanced and metastatic disease, combining chemoradiation with radical surgery may achieve total eradication of disease and disease control in the pelvis. Evidence for resection of metastases to the liver and lung have been extensively reported in the literature. The role of cytoreductive surgery and hyperthermic intraperitoneal chemotherapy for peritoneal metastases is showing promise in achieving locoregional control of peritoneal dissemination. This paper summarizes the recent developments in approaches to rectal cancer surgery at all these time points of the disease natural history.

  14. Fast approach for toner saving

    Science.gov (United States)

    Safonov, Ilia V.; Kurilin, Ilya V.; Rychagov, Michael N.; Lee, Hokeun; Kim, Sangho; Choi, Donchul

    2011-01-01

    Reducing toner consumption is an important task in modern printing devices and has a significant positive ecological impact. Existing toner saving approaches have two main drawbacks: appearance of hardcopy in toner saving mode is worse in comparison with normal mode; processing of whole rendered page bitmap requires significant computational costs. We propose to add small holes of various shapes and sizes to random places inside a character bitmap stored in font cache. Such random perforation scheme is based on processing pipeline in RIP of standard printer languages Postscript and PCL. Processing of text characters only, and moreover, processing of each character for given font and size alone, is an extremely fast procedure. The approach does not deteriorate halftoned bitmap and business graphics and provide toner saving for typical office documents up to 15-20%. Rate of toner saving is adjustable. Alteration of resulted characters' appearance is almost indistinguishable in comparison with solid black text due to random placement of small holes inside the character regions. The suggested method automatically skips small fonts to preserve its quality. Readability of text processed by proposed method is fine. OCR programs process that scanned hardcopy successfully too.

  15. Personalized Management Approach for OSA.

    Science.gov (United States)

    Carberry, Jayne C; Amatoury, Jason; Eckert, Danny J

    2018-03-01

    OSA is a heterogeneous disorder. If left untreated, it has major health, safety, and economic consequences. In addition to varying levels of impairment in pharyngeal anatomy (narrow/collapsible airway), nonanatomical "phenotypic traits" are also important contributors to OSA for most patients. However, the majority of existing therapies (eg, CPAP, oral appliances, weight loss, positional therapy, upper airway surgery) target only the anatomical cause. These are typically administered as monotherapy according to a trial and error management approach in which the majority of patients are first prescribed CPAP. Despite its high efficacy, CPAP adherence remains unacceptably low, and second-line therapies have variable and unpredictable efficacies. Recent advances in knowledge regarding the multiple causes of OSA using respiratory phenotyping techniques have identified new targets or "treatable traits" to direct therapy. Identification of the traits and development of therapies that selectively target one or more of the treatable traits has the potential to personalize the management of this chronic health condition to optimize patient outcomes according to precision medicine principles. This brief review highlights the latest developments and emerging therapies for personalized management approaches for OSA. Copyright © 2017 American College of Chest Physicians. Published by Elsevier Inc. All rights reserved.

  16. Stochastic approach for radionuclides quantification

    Science.gov (United States)

    Clement, A.; Saurel, N.; Perrin, G.

    2018-01-01

    Gamma spectrometry is a passive non-destructive assay used to quantify radionuclides present in more or less complex objects. Basic methods using empirical calibration with a standard in order to quantify the activity of nuclear materials by determining the calibration coefficient are useless on non-reproducible, complex and single nuclear objects such as waste packages. Package specifications as composition or geometry change from one package to another and involve a high variability of objects. Current quantification process uses numerical modelling of the measured scene with few available data such as geometry or composition. These data are density, material, screen, geometric shape, matrix composition, matrix and source distribution. Some of them are strongly dependent on package data knowledge and operator backgrounds. The French Commissariat à l'Energie Atomique (CEA) is developing a new methodology to quantify nuclear materials in waste packages and waste drums without operator adjustment and internal package configuration knowledge. This method suggests combining a global stochastic approach which uses, among others, surrogate models available to simulate the gamma attenuation behaviour, a Bayesian approach which considers conditional probability densities of problem inputs, and Markov Chains Monte Carlo algorithms (MCMC) which solve inverse problems, with gamma ray emission radionuclide spectrum, and outside dimensions of interest objects. The methodology is testing to quantify actinide activity in different kind of matrix, composition, and configuration of sources standard in terms of actinide masses, locations and distributions. Activity uncertainties are taken into account by this adjustment methodology.

  17. A new approach to magic

    Directory of Open Access Journals (Sweden)

    Čvorović Jelena

    2006-01-01

    Full Text Available This paper uses the example of traditional practices of magic to suggest ways to incorporate cultural behaviors within the evolutionary paradigm. The first suggestion is to restrict hypotheses to only identifiable variables. This means avoiding the temptation of following the nonevolutionary social sciences in the practice of basing explanations on unverifiable guesses about what beliefs (or memes in evolutionary jargon may or may not inhabit people's brains. In contrast with previous explanations that magical practices result from beliefs and memes whose primarily purpose is to reduce anxiety, we propose that magic is a form of communication that promotes cooperation and often avoids anti-social behavior. This effect of increased cooperation could explain why traditional forms of magic have probably existed and had significant positive consequences for the participants. To be effective as a means of communication, magical rituals must specify both the content of the message and the receiver of the message. Although the content of the communicative message differs with different types of magic, all magical acts serve a purpose to influence the behavior of the party involved and that is the most significant identifiable effect of such behavior. An advantage of this approach over many previous explanations of magic is that because it focuses on identifiable phenomena, the definitions and explanations used in this approach can be falsified.

  18. Systematic approach to thermal leptogenesis

    Energy Technology Data Exchange (ETDEWEB)

    Frossard, T.; Kartavtsev, A. [Max-Planck-Institut fuer Kernphysik, Heidelberg (Germany); Garny, M. [Deutsches Elektronen-Synchrotron (DESY), Hamburg (Germany); Hohenegger, A. [Ecole Polytechnique Federale de Lausanne, LPPC, BSP (Switzerland); Mitrouskas, D. [Muenchen Univ. (Germany)

    2012-11-15

    In this work we study thermal leptogenesis using non-equilibrium quantum field theory. Starting from fundamental equations for correlators of the quantum fields we describe the steps necessary to obtain quantum kinetic equations for quasiparticles. These can easily be compared to conventional results and overcome conceptional problems inherent in the canonical approach. Beyond CP-violating decays we include also those scattering processes which are tightly related to the decays in a consistent approximation of fourth order in the Yukawa couplings. It is demonstrated explicitly how the S-matrix elements for the scattering processes in the conventional approach are related to two- and three-loop contributions to the effective action. We derive effective decay and scattering amplitudes taking medium corrections and thermal masses into account. In this context we also investigate CP-violating Higgs decay within the same formalism. From the kinetic equations we derive rate equations for the lepton asymmetry improved in that they include quantum-statistical effects and medium corrections to the quasiparticle properties.

  19. Improving immunization approaches to cholera.

    Science.gov (United States)

    Saha, Amit; Rosewell, Alexander; Hayen, Andrew; MacIntyre, C Raina; Qadri, Firdausi

    2017-03-01

    Cholera's impact is greatest in resource-limited countries. In the last decade several large epidemics have led to a global push to improve and implement the tools for cholera prevention and control. Areas covered: PubMed, Google Scholar and the WHO website were searched to review the literature and summarize the current status of cholera vaccines to make recommendations on improving immunization approaches to cholera. Oral cholera vaccines (OCVs) have demonstrated their effectiveness in endemic, outbreak response and emergency settings, highlighting their potential for wider adoption. While two doses of the currently available OCVs are recommended by manufacturers, a single dose would be easier to implement. Encouragingly, recent studies have shown that cold chain requirements may no longer be essential. The establishment of the global OCV stockpile in 2013 has been a major advance in cholera preparedness. New killed and live-attenuated vaccines are being actively explored as candidate vaccines for endemic settings and/or as a traveller's vaccine. The recent advances in cholera vaccination approaches should be considered in the global cholera control strategy. Expert commentary: The development of affordable cholera vaccines is a major success to improve cholera control. New vaccines and country specific interventions will further reduce the burden of this disease globally.

  20. Modeling Approaches in Planetary Seismology

    Science.gov (United States)

    Weber, Renee; Knapmeyer, Martin; Panning, Mark; Schmerr, Nick

    2014-01-01

    Of the many geophysical means that can be used to probe a planet's interior, seismology remains the most direct. Given that the seismic data gathered on the Moon over 40 years ago revolutionized our understanding of the Moon and are still being used today to produce new insight into the state of the lunar interior, it is no wonder that many future missions, both real and conceptual, plan to take seismometers to other planets. To best facilitate the return of high-quality data from these instruments, as well as to further our understanding of the dynamic processes that modify a planet's interior, various modeling approaches are used to quantify parameters such as the amount and distribution of seismicity, tidal deformation, and seismic structure on and of the terrestrial planets. In addition, recent advances in wavefield modeling have permitted a renewed look at seismic energy transmission and the effects of attenuation and scattering, as well as the presence and effect of a core, on recorded seismograms. In this chapter, we will review these approaches.

  1. Psoriasis - The Life Course Approach.

    Science.gov (United States)

    Linder, Michael Dennis; Piaserico, Stefano; Augustin, Matthias; Fortina, Anna Belloni; Cohen, Arnon D; Gieler, Uwe; Jemec, Gregor B E; Kimball, Alexa Boer; Peserico, Andrea; Sampogna, Francesca; Warren, Richard B; de Korte, John

    2016-08-23

    Over the last decades, Life Course Research (LCR), predominantly the domain of sociology, has been increasingly applied in health research, as Life Course Epidemiology (LCE). The latter is concerned with disease patterns over time, accumulation of exposures over time, critical time periods and patterns of risk. We argue that concepts from LCR and LCE could be widely applied in dermatology, in general, and, more precisely, in the study of chronic inflammatory skin diseases, e.g. atopic eczema and psoriasis. The life course approach can generally be applied in two different ways. It may be used in the more traditional manner, in which the disease and its patterns over time are examined as the outcome vari-able. Conversely, it can examine life course as the outcome variable, which is dependent on the disease course, the treatments administered, and other physical or psychosocial environmental exposures. In dermatology, this second application of the LCR concepts is both promising and relevant because of the notable impact of chronic skin diseases on the patients' quality of life. In particular, we argue how LCR may be conducive to a better understanding of the concept of 'Cumulative Life Course Impairment', which is increasingly gaining acceptance. This approach helps identifying not only individuals at risk and particularly vulnerable patients but also critical periods for optimising interventions in order to avoid life course impairment. It also may facilitate more appropriate treatment decisions in clinical practice.

  2. Spinal trauma. An imaging approach

    International Nuclear Information System (INIS)

    Cassar-Pullicino, V.N.; Imhof, H.

    2006-01-01

    The diagnosis of trauma to the spine - where the slightest oversight may have catastrophic results - requires a thorough grasp of the spectrum of resultant pathology as well as the imaging modalities used in making an accurate diagnosis. In Spinal Trauma, the internationally renowned team of experts provides a comprehensive, cutting-edge exposition of the current vital role of imaging in the diagnosis and treatment of injuries to the axial skeleton. Beginning with a valuable clinical perspective of spinal trauma, the book offers the reader a unique overview of the biomechanics underlying the pathology of cervical trauma. Acute trauma topics include: - Optimization of imaging modalities - Malalignment - signs and significance - Vertebral fractures - detection and implications - Classification of thoraco-lumbar fractures - rationale and relevance - Neurovascular injury. Distilling decades of clinical and teaching expertise, the contributors further discuss the current role of imaging in special focus topics, which include: - The pediatric spine - Sports injuries - The rigid spine - Trauma in the elderly - Vertebral collapse, benign and malignant - Spinal trauma therapy - Vertebral fractures and osteoporosis - Neuropathic spine. All throughout the book, the focus is on understanding the injury, and its implications and complications, through 'an imaging approach'. Lavishly illustrated with hundreds of superb MR images and CT scans, and clear full-color drawings, the authors conclude with a look into the future, defining clinical trends and research directions. Spinal Trauma - with its broad scope, practical imaging approach, and current focus - is designed to enhance confidence and accuracy, making it essential reading for clinicians and radiologists at all levels. (orig.)

  3. Approach/avoidance in dreams.

    Science.gov (United States)

    Malcolm-Smith, Susan; Koopowitz, Sheri; Pantelis, Eleni; Solms, Mark

    2012-03-01

    The influential threat simulation theory (TST) asserts that dreaming yields adaptive advantage by providing a virtual environment in which threat-avoidance may be safely rehearsed. We have previously found the incidence of biologically threatening dreams to be around 20%, with successful threat avoidance occurring in approximately one-fifth of such dreams. TST asserts that threat avoidance is over-represented relative to other possible dream contents. To begin assessing this issue, we contrasted the incidence of 'avoidance' dreams with that of their opposite: 'approach' dreams. Because TST states that the threat-avoidance function is only fully activated in ecologically valid (biologically threatening) contexts, we also performed this contrast for populations living in both high- and low-threat environments. We find that 'approach' dreams are significantly more prevalent across both contexts. We suggest these results are more consistent with the view that dreaming is generated by reward-seeking systems than by fear-conditioning systems, although reward-seeking is clearly not the only factor determining the content of dreams. Copyright © 2011 Elsevier Inc. All rights reserved.

  4. Semiclassical approaches to mesoscopic systems

    International Nuclear Information System (INIS)

    Brack, M.

    2001-01-01

    We review semiclassical methods of determining both average trends and quantum shell effects in the properties of finite fermion systems. I. Extended Thomas-Fermi model (ETF): the average, self-consistent mean field can be determined by density variational calculations using the semiclassical gradient-expanded ETF density functional for the kinetic energy. From this, average ground-state properties such as binding energies, densities, separation energies, etc. can be derived. II. Periodic orbit theory (POT): quantum oscillations in a mean-field system can be obtained from the semiclassical trace formula that expresses the quantum-mechanical density of states in terms of the periodic orbits of the corresponding classical system. Only the shortest periodic orbits with highest degeneracy are important for the coarse-grained level density, i.e., for the gross shell effects. Particular uniform approximations are required to treat systems with mixed classical dynamics due to the effects of symmetry breaking and orbit bifurcations. Ill. Local-current approximation (LCA): the collective dynamics of the fermions can be described in linear-response theory, approximating the particle-hole excitation operators semi-classically by local current distributions. The method is suitable in combination with both the ETF density variational approach or with the Kohn-Sham density functional approach for the ground state, and allows one to describe optic response properties such as static polarizabilities and plasmon resonances. Applications of all methods to metal clusters and various mesoscopic nano-structures are given. (author)

  5. Endoscopic transnasal repair of cerebrospinal fluid leaks with and without an encephalocele in pediatric patients: from infants to children.

    Science.gov (United States)

    Ma, Jingying; Huang, Qian; Li, Xiaokui; Huang, Dongsheng; Xian, Junfang; Cui, Shunjiu; Li, Yunchuan; Zhou, Bing

    2015-09-01

    The diagnosis and management of pediatric cerebrospinal fluid (CSF) leak and encephalocele are challenging. The current study aimed to identify patient characteristics, review operative techniques, and evaluate the efficacy and safety of endoscopic endonasal repair in a pediatric population. We retrospectively reviewed the records of pediatric patients who underwent transnasal endoscopic repair of CSF leak with or without a meningocele or an encephalocele at Beijing Tongren Hospital, Capital Medical University, between July 2003 and May 2014. All patients had preoperative radiological evaluations and underwent endoscopic endonasal repair of their skull base defects. Altogether, 23 children (mean age 7.0 years) underwent the procedures. Sixteen cases were congenital, and 7 patients had trauma history. The herniations or defects included meningoencephaloceles in 15 cases, meningoceles in 4 cases, and CSF leak in 4 cases (2 patients had bilateral leaks). The leak or herniation sites were ethmoid roof in 10 patients (one was bilateral), cribriform plate in 5, lateral to the foramen cecum in 3, posterior wall of the frontal sinus in 1, sphenoid sinus in 2, lateral recess of the sphenoid sinus in 1, and sella turcica base in 2. All subjects had favorable clinical outcomes without recurrence during a follow-up of 6-123 months (mean 61.1 months). The endoscopic endonasal approach was the preferred method for repairing CSF leaks with or without an encephalocele in pediatric patients. Compared to traditional operations, this endoscopic procedure is minimally invasive, efficient, and safe.

  6. The Bayesian Approach to Association

    Science.gov (United States)

    Arora, N. S.

    2017-12-01

    The Bayesian approach to Association focuses mainly on quantifying the physics of the domain. In the case of seismic association for instance let X be the set of all significant events (above some threshold) and their attributes, such as location, time, and magnitude, Y1 be the set of detections that are caused by significant events and their attributes such as seismic phase, arrival time, amplitude etc., Y2 be the set of detections that are not caused by significant events, and finally Y be the set of observed detections We would now define the joint distribution P(X, Y1, Y2, Y) = P(X) P(Y1 | X) P(Y2) I(Y = Y1 + Y2) ; where the last term simply states that Y1 and Y2 are a partitioning of Y. Given the above joint distribution the inference problem is simply to find the X, Y1, and Y2 that maximizes posterior probability P(X, Y1, Y2| Y) which reduces to maximizing P(X) P(Y1 | X) P(Y2) I(Y = Y1 + Y2). In this expression P(X) captures our prior belief about event locations. P(Y1 | X) captures notions of travel time, residual error distributions as well as detection and mis-detection probabilities. While P(Y2) captures the false detection rate of our seismic network. The elegance of this approach is that all of the assumptions are stated clearly in the model for P(X), P(Y1|X) and P(Y2). The implementation of the inference is merely a by-product of this model. In contrast some of the other methods such as GA hide a number of assumptions in the implementation details of the inference - such as the so called "driver cells." The other important aspect of this approach is that all seismic knowledge including knowledge from other domains such as infrasound and hydroacoustic can be included in the same model. So, we don't need to separately account for misdetections or merge seismic and infrasound events as a separate step. Finally, it should be noted that the objective of automatic association is to simplify the job of humans who are publishing seismic bulletins based on this

  7. Variational approach to 68 Se

    International Nuclear Information System (INIS)

    Petrovici, A.; Schmid, K.W.; Faessler, A.; Baktash, C.; Shashi, P.

    1999-01-01

    For a unified description of the structure of medium mass proton-rich nuclei at low as well as high angular momenta we used the complex version of the Excited Vampir approach. We employed chains of variational calculations based on symmetry-projected essentially complex Hartree-Fock-Bogoliubov (HFB) vacua which include neutron-proton pairing and unnatural-parity correlations. Since the Vampir approaches allow the use of rather large model spaces and of general two-body interactions, large-scale nuclear structure studies going far beyond the abilities of the conventional shell-model configuration-mixing approach are possible. Furthermore, since these approaches provide detailed spectroscopic information for the lowest few states for each spin and parity, they also have considerable advantages with respect to the shell-model Monte Carlo method in which only expectation values of operators in the thermodynamic ensembles or the ground state can be calculated. Our previous investigations on microscopic aspects of shape coexistence in N∼Z nuclei in the A∼70 mass region indicated the presence of a strong competition between particular configurations based on large and small oblate and prolate quadrupole deformations. Furthermore, since in N = Z nuclei neutrons and protons fill the same single particle orbits, the isovector neutron-proton and the like-nucleon pairing correlations were found to be strongly competitive in even-even systems. In addition, the neutron and proton alignments with increasing angular momentum occur simultaneously in these nuclei. On the other hand the theoretical results suggest that certain properties of these nuclei are extremely sensitive to small variations of particular parts of the effective Hamiltonian. Thus, our results indicate that the oblate-prolate coexistence and mixing at low spins depend on the strengths of the neutron-proton T = 0 matrix elements involving nucleons occupying f 5/2 (f 7/2 ) and g 9/2 single particle orbits

  8. Kinetic approach to relativistic dissipation

    Science.gov (United States)

    Gabbana, A.; Mendoza, M.; Succi, S.; Tripiccione, R.

    2017-08-01

    Despite a long record of intense effort, the basic mechanisms by which dissipation emerges from the microscopic dynamics of a relativistic fluid still elude complete understanding. In particular, several details must still be finalized in the pathway from kinetic theory to hydrodynamics mainly in the derivation of the values of the transport coefficients. In this paper, we approach the problem by matching data from lattice-kinetic simulations with analytical predictions. Our numerical results provide neat evidence in favor of the Chapman-Enskog [The Mathematical Theory of Non-Uniform Gases, 3rd ed. (Cambridge University Press, Cambridge, U.K., 1970)] procedure as suggested by recent theoretical analyses along with qualitative hints at the basic reasons why the Chapman-Enskog expansion might be better suited than Grad's method [Commun. Pure Appl. Math. 2, 331 (1949), 10.1002/cpa.3160020403] to capture the emergence of dissipative effects in relativistic fluids.

  9. Branding approach and valuation models

    Directory of Open Access Journals (Sweden)

    Mamula Tatjana

    2006-01-01

    Full Text Available Much of the skill of marketing and branding nowadays is concerned with building equity for products whose characteristics, pricing, distribution and availability are really quite close to each other. Brands allow the consumer to shop with confidence. The real power of successful brands is that they meet the expectations of those that buy them or, to put it another way, they represent a promise kept. As such they are a contract between a seller and a buyer: if the seller keeps to its side of the bargain, the buyer will be satisfied; if not, the buyer will in future look elsewhere. Understanding consumer perceptions and associations is an important first step to understanding brand preferences and choices. In this paper, we discuss different models to measure value of brand according to couple of well known approaches according to request by companies. We rely upon several empirical examples.

  10. Therapeutic approaches for celiac disease

    Science.gov (United States)

    Plugis, Nicholas M.; Khosla, Chaitan

    2015-01-01

    Celiac disease is a common, lifelong autoimmune disorder for which dietary control is the only accepted form of therapy. A strict gluten-free diet is burdensome to patients and can be limited in efficacy, indicating there is an unmet need for novel therapeutic approaches to supplement or supplant dietary therapy. Many molecular events required for disease pathogenesis have been recently characterized and inspire most current and emerging drug-discovery efforts. Genome-wide association studies (GWAS) confirm the importance of human leukocyte antigen genes in our pathogenic model and identify a number of new risk loci in this complex disease. Here, we review the status of both emerging and potential therapeutic strategies in the context of disease pathophysiology. We conclude with a discussion of how genes identified during GWAS and follow-up studies that enhance susceptibility may offer insight into developing novel therapies. PMID:26060114

  11. Possible State Approaches to Cryptocurrencies

    Directory of Open Access Journals (Sweden)

    Jan Lansky

    2018-01-01

    Full Text Available Cryptocurrencies are a type of digital currencies that are relying on cryptographic proofs for confirmation of transactions. Cryptocurrencies usually achieve a unique combination of three features: ensuring limited anonymity, independence from central authority and double spending attack protection. No other group of currencies, including fiat currencies, has this combination of features. We will define cryptocurrency ownership and account anonymity. We will define cryptocurrency ownership and account anonymity. We will introduce a classification of the types of approaches to regulation of cryptocurrencies by various individual countries. We will present the risks that the use of cryptocurrencies involves and the possibilities of prevention of those risks. We will present the possible use of cryptocurrencies for the benefit of the state. The conclusion addresses the implications of adoption of a cryptocurrency as a national currency.

  12. SIMD approach to IDA* search

    Science.gov (United States)

    Lyons, Gary; Cook, Dianne J.

    1992-03-01

    Heuristic search is a fundamental component of artificial intelligence applications. Because search routines are frequently a computational bottleneck, numerous methods have been explored to increase the efficiency of search. While sequential search methods use exponential amounts of storage and yield exponential run times, parallel algorithms designed for MIMD machines significantly reduce the time spent in search. In this paper, we present a massively- parallel SIMD approach to search named MIDA* search. The components of MIDA* include a very fast distribution algorithm which biases the search to one side of the tree, and an incrementally-deepening depth-first search of all the processors in parallel. We show the results of applying MIDA* to instances of the fifteen puzzle problem. Results reveal an efficiency of 76% and a speedup of 8553% and 492% over serial and 16- processor MIMD algorithms, respectively.

  13. Gene Therapy Approaches to Immunodeficiency.

    Science.gov (United States)

    Ghosh, Sujal; Gaspar, H Bobby

    2017-10-01

    Transfer of gene-corrected autologous hematopoietic stem cells in patients with primary immunodeficiencies has emerged as a new therapeutic approach. Patients with various conditions lacking a suitable donor have been treated with retroviral vectors and a gene-addition strategy. Initial promising results were shadowed by the occurrence of malignancies in some of these patients. Current trials, developed in the last decade, use safer viral vectors to overcome the risk of genotoxicity and have led to improved clinical outcomes. This review reflects the progresses made in specific disorders, including adenosine deaminase deficiency, X-linked severe combined immunodeficiency, chronic granulomatous disease, and Wiskott-Aldrich syndrome. Copyright © 2017 Elsevier Inc. All rights reserved.

  14. Multivariate approaches in plant science

    DEFF Research Database (Denmark)

    Gottlieb, D.M.; Schultz, j.; Bruun, Susanne Wrang

    2004-01-01

    includes labor intensive work in order to manage, handle and analyze data. The field of classical proteomics should therefore be extended to also include handling of large datasets in an objective way. The separation obtained by two-dimensional electrophoresis and mass spectrometry gives rise to huge...... is to encircle the identity of proteins of interest. However, the overall relation between proteins must also be explained. Classical proteomics consist of separation and characterization, based on two-dimensional electrophoresis, trypsin digestion, mass spectrometry and database searching. Characterization...... amount of data. We present a multivariate approach to the handling of data in proteomics with the advantage that protein patterns can be spotted at an early stage and consequently the proteins selected for sequencing can be selected intelligently. These methods can also be applied to other data...

  15. Raman spectroscopy an intensity approach

    CERN Document Server

    Guozhen, Wu

    2017-01-01

    This book summarizes the highlights of our work on the bond polarizability approach to the intensity analysis. The topics covered include surface enhanced Raman scattering, Raman excited virtual states and Raman optical activity (ROA). The first chapter briefly introduces the Raman effect in a succinct but clear way. Chapter 2 deals with the normal mode analysis. This is a basic tool for our work. Chapter 3 introduces our proposed algorithm for the Raman intensity analysis. Chapter 4 heavily introduces the physical picture of Raman virtual states. Chapter 5 offers details so that the readers can have a comprehensive idea of Raman virtual states. Chapter 6 demonstrates how this bond polarizability algorithm is extended to ROA intensity analysis. Chapters 7 and 8 offer details on ROA, showing many findings on ROA mechanism that were not known or neglected before. Chapter 9 introduces our proposed classical treatment on ROA which, as combined with the results from the bond polarizability analysis, leads to a com...

  16. Queueing networks a fundamental approach

    CERN Document Server

    Dijk, Nico

    2011-01-01

    This handbook aims to highlight fundamental, methodological and computational aspects of networks of queues to provide insights and to unify results that can be applied in a more general manner.  The handbook is organized into five parts: Part 1 considers exact analytical results such as of product form type. Topics include characterization of product forms by physical balance concepts and simple traffic flow equations, classes of service and queue disciplines that allow a product form, a unified description of product forms for discrete time queueing networks, insights for insensitivity, and aggregation and decomposition results that allow subnetworks to be aggregated into single nodes to reduce computational burden. Part 2 looks at monotonicity and comparison results such as for computational simplification by either of two approaches: stochastic monotonicity and ordering results based on the ordering of the proces generators, and comparison results and explicit error bounds based on an underlying Markov r...

  17. Episodic Memory: A Comparative Approach

    Science.gov (United States)

    Martin-Ordas, Gema; Call, Josep

    2013-01-01

    Historically, episodic memory has been described as autonoetic, personally relevant, complex, context-rich, and allowing mental time travel. In contrast, semantic memory, which is theorized to be free of context and personal relevance, is noetic and consists of general knowledge of facts about the world. The field of comparative psychology has adopted this distinction in order to study episodic memory in non-human animals. Our aim in this article is not only to reflect on the concept of episodic memory and the experimental approaches used in comparative psychology to study this phenomenon, but also to provide a critical analysis of these paradigms. We conclude the article by providing new avenues for future research. PMID:23781179

  18. Epidemiological Approaches to Metal Toxicology

    DEFF Research Database (Denmark)

    Grandjean, Philippe; Budtz-Jørgensen, Esben

    2014-01-01

    Epidemiological methods are crucial to extract as much valid information as possible from human metal exposures. Thus, modern epidemiological approaches have elucidated human health effects that were not apparent in the past. At the same time, metal toxicology has served as a useful arena...... for testing and further refining methods for study design and data analysis. In contrast to most organic compounds, metals are not broken down, and many of them are retained in the body for long periods, thereby facilitating exposure assessment. In conjunction with the use of inexpensive metal analytical...... to their propensity to cause chronic or delayed toxicity, epidemiological studies of metal toxicity have focused on a wide variety of organ systems, subtle effects as well as mortality, and differences in susceptibility. Toxic metals often serve as paradigms of environmental and occupational toxicity...

  19. Lignin Sulfonation - A different Approach

    DEFF Research Database (Denmark)

    Bjørkmann, Anders

    2001-01-01

    The research on sulfite pulping has been characterized by the attempts to explain its chemistry. The. different approach presented is incited by perceptions about the (still) unsolved problem of the ultrastructural features of lignin in wood. A simple kinetic model has been chosen to describe...... the reaction order of lignin as "concentration" (weight) in the dissolution kinetics, the cooking liquor being used in substantial excess. Three states of lignin were used: in wood as sawdust (W), in milled. wood (MW) and as milled wood lignin (MWL). Cooks were performed at pH 1.5, and 6. (measured at room...... temperature). The lignin was also modified chemically in two ways: alkaline borohydride reduction and diazomethane methylation. The reaction order (with the kinetics used) was found to be about 2/3, which is the value to be expected for particles of equal size reacting, at the particle surface. The cooks were...

  20. IAEA safeguards approaches and goals

    International Nuclear Information System (INIS)

    Khlebnikov, Nikolai

    2001-01-01

    IAEA safeguards provide a technical means of verifying that political obligations undertaken by States party to international agreements relating to the peaceful uses of nuclear energy are being honored. The Agency assures the international community that States party to Safeguards Agreements are complying with their undertaking not to use facilities and divert nuclear materials from peaceful uses to the manufacture of nuclear explosive devices. The task of IAEA safeguards can be summed up as to detect diversion of nuclear materials committed to peaceful uses of nuclear energy, or the misuse of equipment or facilities subject to certain safeguards agreements, and to deter such diversion or misuse through the risk of early detection. This lecture concentrates on the factors the Agency takes into account in designing and implementing safeguards approaches at facilities. (author)

  1. Chaotic inflation: A numerical approach

    International Nuclear Information System (INIS)

    Biller, P.; Pertuccione, F.

    1991-01-01

    A numerical study of chaotic inflation is presented. Following a semiclassical treatment of quantum effects, the dynamics is described as a random process. The relevant Langevin equation is then integrated numerically for a large number of realizations and results are evaluated as ensemble averages. For the understanding of the global structure of the universe the fact that different domains of the universe have different growth rates is important. This is handled by a new modified algorithm. The simulation results for the probability distribution functions at constant and proper volume are given for two typical initial conditions. We compare them to the approximate results of an already existing analytical approach. The picture of an eternally existing self-reproducing universe is confirmed. (orig.)

  2. A programming approach to computability

    CERN Document Server

    Kfoury, A J; Arbib, Michael A

    1982-01-01

    Computability theory is at the heart of theoretical computer science. Yet, ironically, many of its basic results were discovered by mathematical logicians prior to the development of the first stored-program computer. As a result, many texts on computability theory strike today's computer science students as far removed from their concerns. To remedy this, we base our approach to computability on the language of while-programs, a lean subset of PASCAL, and postpone consideration of such classic models as Turing machines, string-rewriting systems, and p. -recursive functions till the final chapter. Moreover, we balance the presentation of un solvability results such as the unsolvability of the Halting Problem with a presentation of the positive results of modern programming methodology, including the use of proof rules, and the denotational semantics of programs. Computer science seeks to provide a scientific basis for the study of information processing, the solution of problems by algorithms, and the design ...

  3. Computational approach to Riemann surfaces

    CERN Document Server

    Klein, Christian

    2011-01-01

    This volume offers a well-structured overview of existent computational approaches to Riemann surfaces and those currently in development. The authors of the contributions represent the groups providing publically available numerical codes in this field. Thus this volume illustrates which software tools are available and how they can be used in practice. In addition examples for solutions to partial differential equations and in surface theory are presented. The intended audience of this book is twofold. It can be used as a textbook for a graduate course in numerics of Riemann surfaces, in which case the standard undergraduate background, i.e., calculus and linear algebra, is required. In particular, no knowledge of the theory of Riemann surfaces is expected; the necessary background in this theory is contained in the Introduction chapter. At the same time, this book is also intended for specialists in geometry and mathematical physics applying the theory of Riemann surfaces in their research. It is the first...

  4. An approach to risk assessment

    DEFF Research Database (Denmark)

    Simonsen, L.; Lund, S. P.; Hass, Ulla

    1998-01-01

    of Ministers with the task to propose criteria for neurotoxicity. Functional effects on the nervous system, such as reduction in memory and learning ability, decrease in attention, and alteration of behavior due to toxic chemicals in the environment is now being acknowledged as an important public health...... problem. This change in concern from obvious effects of high dose exposure to the more subtle effects of environmental exposure to neurotoxicants was incorporated in the criteria. The new criteria for evaluating neurotoxicity data has subsequently been used on 79 common industrial chemicals. The results...... indicate that numerous persons are exposed in the working as well as in the general environment to several chemicals, for which almost no data on the effect on subtle neurophysiological functions are available. Development of an approach to risk assessment dealing with this problem is a major challenge...

  5. Pharmacotherapy of Schizophrenia: Ploypharmacy Approaches

    Directory of Open Access Journals (Sweden)

    Fatemeh Rahiminejad

    2010-07-01

    Full Text Available "nSchizophrenia is a debilitating illness, rating as one of the leading causes of lost years of quality of life. The illness imposes a disproportionate burden on patients and their families, healthcare systems and society. Pharmacological management is the cornerstone of treatment of schizophrenia, and antipsychotics, both first generation of antipsychotics and second generation of antipsychotics, are efficacious in reducing levels of psychopathology in acute episodes of schizophrenia. Clearly a need for innovative treatment strategies in schizophrenia that will ensure increased effectiveness against negative symptoms and cognitive dysfunction dysfunction. Therefore, in majority of cases polypharmacy is one of the effective approaches. This review focused on polypharmacy in the treatment of schizophrenia and in particular negative symptoms.

  6. Entropy: The Markov Ordering Approach

    Directory of Open Access Journals (Sweden)

    Alexander N. Gorban

    2010-05-01

    Full Text Available The focus of this article is on entropy and Markov processes. We study the properties of functionals which are invariant with respect to monotonic transformations and analyze two invariant “additivity” properties: (i existence of a monotonic transformation which makes the functional additive with respect to the joining of independent systems and (ii existence of a monotonic transformation which makes the functional additive with respect to the partitioning of the space of states. All Lyapunov functionals for Markov chains which have properties (i and (ii are derived. We describe the most general ordering of the distribution space, with respect to which all continuous-time Markov processes are monotonic (the Markov order. The solution differs significantly from the ordering given by the inequality of entropy growth. For inference, this approach results in a convex compact set of conditionally “most random” distributions.

  7. Molecular approaches for bacterial azoreductases

    Directory of Open Access Journals (Sweden)

    Montira Leelakriangsak

    2013-12-01

    Full Text Available Azo dyes are the dominant types of synthetic dyes, widely used in textiles, foods, leather, printing, tattooing, cosmetics, and pharmaceutical industries. Many microorganisms are able to decolorize azo dyes, and there is increasing interest in biological waste treatment methods. Bacterial azoreductases can cleave azo linkages (-N=N- in azo dyes, forming aromatic amines. This review mainly focuses on employing molecular approaches, including gene manipulation and recombinant strains, to study bacterial azoreductases. The construction of the recombinant protein by cloning and the overexpression of azoreductase is described. The mechanisms and function of bacterial azoreductases can be studied by other molecular techniques discussed in this review, such as RT-PCR, southern blot analysis, western blot analysis, zymography, and muta-genesis in order to understand bacterial azoreductase properties, function and application. In addition, understanding the regulation of azoreductase gene expression will lead to the systematic use of gene manipulation in bacterial strains for new strategies in future waste remediation technologies.

  8. Topological approach of Jungian psychology.

    Science.gov (United States)

    Viret, Jacques

    2010-09-01

    In this work, we compare two global approaches which are usually considered as completely unconnected one with the other. The former is Thom's topology and the latter is Jung's psychology. More precisely, it seemed to us interesting to adapt some morphologies of Thom's catastrophe theory to some Jung's notions. Thus, we showed that the swallowtail, which is one of these morphologies, was able to describe geometrically the structural organisation of the psyche according to Jung, with its collective unconscious, personal unconscious and conscious. Moreover, we have correlated this morphology with Jung's evolutive processes like individualization and individuation. These comparisons incited us to think that some morphologies of Thom's catastrophe theory are the geometrical dealing of Jung's archetypes.

  9. A Dialogic Approach to Pragmatics

    Directory of Open Access Journals (Sweden)

    Иштван Кечкеш

    2016-12-01

    Full Text Available This paper focuses on how the limits of pragmatics - as long as it is restricted to the analysis of one utterance at a time - are overcome by including the hearer not only as interpreter who tries to understand the speaker’s utterance but as an interlocutor who tries to come to an understanding with the speaker. The goal of the paper is not to describe and analyze the dialogue approach rather explain what inner developments in the pragmatics paradigm have made it necessary to move in a dialogic direction, specifically emphasizing the importance of evaluating speaker meaning from the perspective of the speaker rather than from the perspective of the hearer and the double role of the interlocutor (speaker-hearer.

  10. Quantum Plasmas An Hydrodynamic Approach

    CERN Document Server

    Haas, Fernando

    2011-01-01

    This book provides an overview of the basic concepts and new methods in the emerging scientific area known as quantum plasmas. In the near future, quantum effects in plasmas will be unavoidable, particularly in high density scenarios such as those in the next-generation intense laser-solid density plasma experiment or in compact astrophysics objects. Currently, plasmas are in the forefront of many intriguing questions around the transition from microscopic to macroscopic modeling of charged particle systems. Quantum Plasmas: an Hydrodynamic Approach is devoted to the quantum hydrodynamic model paradigm, which, unlike straight quantum kinetic theory, is much more amenable to investigate the nonlinear realm of quantum plasmas. The reader will have a step-by-step construction of the quantum hydrodynamic method applied to plasmas. The book is intended for specialists in classical plasma physics interested in methods of quantum plasma theory, as well as scientists interested in common aspects of two major areas of...

  11. Hydrogeological challenges through gender approaches

    Science.gov (United States)

    Di Lorenzo, Maria Rosaria; Saltari, Davide; Di Giacomo, Tullia Valeria

    2017-04-01

    Women and Men play a different role in the society, tied from the differences (physical, biological, somatic, etc…) typical of each one. In the last decades, more gender approach has been introduced in a number of fields including the hydrogeological risk. Experiences, needs and potential of each one, women and men, covers both the risk reduction before the occurrence of extreme events (vulnerability assessment and prediction of the expected risk), then in the next emergency and intervention in follow-up actions to the overcoming of the event for the return to everyday life. The response of the extreme hydrological events are also subordinated from gender participation and it is closely related from other aspects, as natural disasters (flood events), gender inequalities and urban floodings. These aspects are also scheduled by the different approaches: a woman focuses different primary and social aspects than a man. How women can help organizations offering new 'policies' and government is the main aspect to be considered and how a gender approach can mitigate disasters to hydrological risk. It depends on some factors: gender inequalities (gender perception and sensibility), importance of natural disasters and urban floodings. Gender inequalities can match both in the natural disasters and urban floodings in a relevant way. ICT solutions can also give a helpful framework to accelerate and focus the quicker condition to get the better approach and solution. Gender has a particular significant, explanatory variable in disaster research. Many studies, show how women have higher mortality and morbidity rates than men during natural disasters, especially in lower income countries. In the aftermath disasters, at the same time, specific responsibilities on women are imposed from the gendered division of labour. Furthermore gender differences are sometimes attributed to traditional women's roles, discrimination, lower physical strength, nutritional deficiencies, etc. as

  12. Computer architecture a quantitative approach

    CERN Document Server

    Hennessy, John L

    2019-01-01

    Computer Architecture: A Quantitative Approach, Sixth Edition has been considered essential reading by instructors, students and practitioners of computer design for over 20 years. The sixth edition of this classic textbook is fully revised with the latest developments in processor and system architecture. It now features examples from the RISC-V (RISC Five) instruction set architecture, a modern RISC instruction set developed and designed to be a free and openly adoptable standard. It also includes a new chapter on domain-specific architectures and an updated chapter on warehouse-scale computing that features the first public information on Google's newest WSC. True to its original mission of demystifying computer architecture, this edition continues the longstanding tradition of focusing on areas where the most exciting computing innovation is happening, while always keeping an emphasis on good engineering design.

  13. Diffraction operators in paraxial approach

    Science.gov (United States)

    Lasso, William; Navas, Marianela; Añez, Liz; Urdaneta, Romer; Díaz, Leonardo; Torres, César O.

    2014-07-01

    Nowadays, research in the field of science education points to the creation of alternative ways of teaching contents encouraging the development of more elaborate reasoning, where a high degree of abstraction and generalization of scientific knowledge prevails. On that subject, this research shows a didactic alternative proposal for the construction of Fresnel and Fraunhoffer diffraction concepts applying the Fourier transform technique in the study of electromagnetic waves propagation in free space. Curvature transparency and Fourier sphere operators in paraxial approximation are used in order to make the usual laborious mathematical approach easier. The main result shows that the composition of optic metaxial operators results in the discovery of a simpler way out of the standard electromagnetic wave propagation in free space between a transmitter and a receptor separated from a given distance. This allows to state that the didactic proposal shown encourages the construction of Fresnel and Fraunhoffer diffraction concepts in a more effective and easier way than the traditional teaching.

  14. Four Approaches to Project Evaluation

    DEFF Research Database (Denmark)

    Laursen, Markus; Svejvig, Per; Rode, Anna Le Gerstrøm

    management methodologies that work and combat project failure, and research methods that can assess effective project management and methodologies, as well as empirical research on the actuality of projects as practice, evaluation research on projects including project management and methodologies is scarce....... Each of the framework’s four approaches provides a distinct evaluation that sheds light on some issues while leaving others unattended. Following these lines, the paper calls for more multi-faceted project evaluations. Introducing a framework that can help analyze existing evaluations and structure...... upcoming evaluations by highlighting beneficial aspects and/or revealing hidden issues, the aim of this paper is to contribute to the theoretical and practical field of project management. The paper contributes to project theory and practice by inspiring project researchers and aiding project workers...

  15. Special relativity a heuristic approach

    CERN Document Server

    Hassani, Sadri

    2017-01-01

    Special Relativity: A Heuristic Approach provides a qualitative exposition of relativity theory on the basis of the constancy of the speed of light. Using Einstein's signal velocity as the defining idea for the notion of simultaneity and the fact that the speed of light is independent of the motion of its source, chapters delve into a qualitative exposition of the relativity of time and length, discuss the time dilation formula using the standard light clock, explore the Minkowski four-dimensional space-time distance based on how the time dilation formula is derived, and define the components of the two-dimensional space-time velocity, amongst other topics. Provides a heuristic derivation of the Minkowski distance formula Uses relativistic photography to see Lorentz transformation and vector algebra manipulation in action Includes worked examples to elucidate and complement the topic being discussed Written in a very accessible style

  16. Computational Approaches to Vestibular Research

    Science.gov (United States)

    Ross, Muriel D.; Wade, Charles E. (Technical Monitor)

    1994-01-01

    The Biocomputation Center at NASA Ames Research Center is dedicated to a union between computational, experimental and theoretical approaches to the study of neuroscience and of life sciences in general. The current emphasis is on computer reconstruction and visualization of vestibular macular architecture in three-dimensions (3-D), and on mathematical modeling and computer simulation of neural activity in the functioning system. Our methods are being used to interpret the influence of spaceflight on mammalian vestibular maculas in a model system, that of the adult Sprague-Dawley rat. More than twenty 3-D reconstructions of type I and type II hair cells and their afferents have been completed by digitization of contours traced from serial sections photographed in a transmission electron microscope. This labor-intensive method has now been replace d by a semiautomated method developed in the Biocomputation Center in which conventional photography is eliminated. All viewing, storage and manipulation of original data is done using Silicon Graphics workstations. Recent improvements to the software include a new mesh generation method for connecting contours. This method will permit the investigator to describe any surface, regardless of complexity, including highly branched structures such as are routinely found in neurons. This same mesh can be used for 3-D, finite volume simulation of synapse activation and voltage spread on neuronal surfaces visualized via the reconstruction process. These simulations help the investigator interpret the relationship between neuroarchitecture and physiology, and are of assistance in determining which experiments will best test theoretical interpretations. Data are also used to develop abstract, 3-D models that dynamically display neuronal activity ongoing in the system. Finally, the same data can be used to visualize the neural tissue in a virtual environment. Our exhibit will depict capabilities of our computational approaches and

  17. Design approaches to experimental mediation☆

    Science.gov (United States)

    Pirlott, Angela G.; MacKinnon, David P.

    2016-01-01

    Identifying causal mechanisms has become a cornerstone of experimental social psychology, and editors in top social psychology journals champion the use of mediation methods, particularly innovative ones when possible (e.g. Halberstadt, 2010, Smith, 2012). Commonly, studies in experimental social psychology randomly assign participants to levels of the independent variable and measure the mediating and dependent variables, and the mediator is assumed to causally affect the dependent variable. However, participants are not randomly assigned to levels of the mediating variable(s), i.e., the relationship between the mediating and dependent variables is correlational. Although researchers likely know that correlational studies pose a risk of confounding, this problem seems forgotten when thinking about experimental designs randomly assigning participants to levels of the independent variable and measuring the mediator (i.e., “measurement-of-mediation” designs). Experimentally manipulating the mediator provides an approach to solving these problems, yet these methods contain their own set of challenges (e.g., Bullock, Green, & Ha, 2010). We describe types of experimental manipulations targeting the mediator (manipulations demonstrating a causal effect of the mediator on the dependent variable and manipulations targeting the strength of the causal effect of the mediator) and types of experimental designs (double randomization, concurrent double randomization, and parallel), provide published examples of the designs, and discuss the strengths and challenges of each design. Therefore, the goals of this paper include providing a practical guide to manipulation-of-mediator designs in light of their challenges and encouraging researchers to use more rigorous approaches to mediation because manipulation-of-mediator designs strengthen the ability to infer causality of the mediating variable on the dependent variable. PMID:27570259

  18. Spinal trauma. An imaging approach

    Energy Technology Data Exchange (ETDEWEB)

    Cassar-Pullicino, V.N. [The Robert Jones and Agnes Hunt Orthopaedic Hospital, Oswestry, Shropshire (United Kingdom). Dept. of Radiology; Imhof, H. [University and General Hospital Vienna (Austria). Dept. of Radiodiagnostics

    2006-07-01

    The diagnosis of trauma to the spine - where the slightest oversight may have catastrophic results - requires a thorough grasp of the spectrum of resultant pathology as well as the imaging modalities used in making an accurate diagnosis. In Spinal Trauma, the internationally renowned team of experts provides a comprehensive, cutting-edge exposition of the current vital role of imaging in the diagnosis and treatment of injuries to the axial skeleton. Beginning with a valuable clinical perspective of spinal trauma, the book offers the reader a unique overview of the biomechanics underlying the pathology of cervical trauma. Acute trauma topics include: - Optimization of imaging modalities - Malalignment - signs and significance - Vertebral fractures - detection and implications - Classification of thoraco-lumbar fractures - rationale and relevance - Neurovascular injury. Distilling decades of clinical and teaching expertise, the contributors further discuss the current role of imaging in special focus topics, which include: - The pediatric spine - Sports injuries - The rigid spine - Trauma in the elderly - Vertebral collapse, benign and malignant - Spinal trauma therapy - Vertebral fractures and osteoporosis - Neuropathic spine. All throughout the book, the focus is on understanding the injury, and its implications and complications, through 'an imaging approach'. Lavishly illustrated with hundreds of superb MR images and CT scans, and clear full-color drawings, the authors conclude with a look into the future, defining clinical trends and research directions. Spinal Trauma - with its broad scope, practical imaging approach, and current focus - is designed to enhance confidence and accuracy, making it essential reading for clinicians and radiologists at all levels. (orig.)

  19. A Zen Approach to Volunteer Management.

    Science.gov (United States)

    Barnett, Michael L.; Cahill, Gloria

    2002-01-01

    New York University's Zen approach to community service focuses on the principles of mindfulness, awareness, compassion, and engagement in the present moment. It enables a more holistic approach to the measurement of volunteer management objectives. (SK)

  20. Dynamical System Approaches to Combinatorial Optimization

    DEFF Research Database (Denmark)

    Starke, Jens

    2013-01-01

    Several dynamical system approaches to combinatorial optimization problems are described and compared. These include dynamical systems derived from penalty methods; the approach of Hopfield and Tank; self-organizing maps, that is, Kohonen networks; coupled selection equations; and hybrid methods...

  1. A Gestalt Approach to Psychological Education.

    Science.gov (United States)

    Childers, John H., Jr.; Basse, Don T.

    1980-01-01

    Gestalt approaches serve as a valuable tool for psychological education. They serve to enhance self-awareness and responsibility. Gestalt approaches can enliven a curriculum and promote self-understanding. Exercises are presented. (Author)

  2. Biliary lithiasis approach in open laparoscopy

    International Nuclear Information System (INIS)

    Pose, J.; Hermida, M.; Berhouet, H.; Delgado, F.

    2000-01-01

    Laparoscopic approach is currently the elective approach in the treatment of non complicated biliary lithiasis.There was a time when an umbilical herniation presented a series of problems at the time of deciding on the approach to be taken.The paper refers to 2 cases of laparoscopic approach in the treatment of symptomatised biliary lithiasis, with an open laparoscopy technique through umbilical hernia ton ring.The repair of herniation was performed in the same operative act with good immediate results

  3. A systems approach to traditional oriental medicine

    DEFF Research Database (Denmark)

    Kim, Hyun Uk; Ryu, Jae Yong; Lee, Jong Ok

    2015-01-01

    Analyzing structural similarities between compounds derived from traditional oriental medicine and human metabolites is a systems-based approach that can help identify mechanisms of action and suggest approaches to reduce toxicity.......Analyzing structural similarities between compounds derived from traditional oriental medicine and human metabolites is a systems-based approach that can help identify mechanisms of action and suggest approaches to reduce toxicity....

  4. [Risk factors of postoperative meningitis in patients with chiasm-sellar tumors].

    Science.gov (United States)

    Popugaev, K A; Savin, I A; Ershova, O N; Kurdyumova, N V; Tabasaransky, T F; Oshorov, A V; Kadashev, B A; Kalinin, P L; Kutin, M A

    2014-01-01

    Postoperative intracranial infectious complications are one of the most topical problems of neurosurgical intensive care due to theirs significant capability to impair outcomes of the main disease. To define the risk factors of postoperative meningitis in patients with chiasm-sellar tumors. 1. to define the effect of somatic and intracranial risk factors on occurrence of postoperative meningitis in patients after transsphenoidal and transcranial approaches to the tumor. 2. To define the effect of postoperative meningitis on outcomes of treatment in patients after transsphenoidal and transcranial approaches to the tumor. Somatic and intracranial risk factors of occurrence of postoperative meningitis (pneumonia, urinary tract infection, sepsis, intra-abdominal hypertension, the presence of external ventricular and lumbar drainage, monitoring of intracranial pressure, cerebrospinal fluid, and reoperation) were fixed every day. The study was conducted in the ICU of the Burdenko from October, 2010 to July, 2012. The 34 patients (19 males, 15 females) were included in the study (average age 47.5 years). The patients were divided into two groups; 17 patients each group. The group-1 included patients after transcranial approach to the tumor and the group-2 included patients after transsphenoidal approach. In the group-1 a meningitis occurred in 3 patients (17.6% +/- 9.2%, DI [-0.4 - 35.6]). In the group-2 a meningitis occurred in 7 patients (41.2% +/- 11.9) DI 95% [17.8 - 64.4]. Accumulation of cerebrospinal fluid under the skin flap authentically increased a risk of a meningitis occurrence in patients after transcranial approach to the tumor (p = 0.031). There was no defined statistical significance of other risk factors. But there was defined a trend of the increasing of meningitis occurrence in patients after transsphenoidal approach in case of lumbar drainage or reoperation. Duration of mechanical ventilation and ICU stay in patients with meningitis was authentically

  5. Marital Counseling: An Integrated Brief Therapy Approach.

    Science.gov (United States)

    Magnuson, Sandy; Norem, Ken

    1998-01-01

    Addresses advantages of, and potential pitfalls in, integrated approaches to marital counseling. Presents a sequential approach in which various approaches to marital counseling are integrated without jeopardizing internal consistency and uniformity in treatment. Offers precounseling considerations and procedures for a five-session series.…

  6. Comprehensive Approach Workshop: Hard Problem First Steps

    Science.gov (United States)

    2011-10-01

    solving hard problems in general. The workshop participants agreed that the Comprehensive Approach is about entities working together towards the...généralement des conflits humains . Ils ont conclu que des problèmes difficiles ce qui utiliser « Comprehensive Approach » sont similaires au problème...Comprehensive Approach Solution .......................................................................................... 6 3.1 Working Definition

  7. Risk communication: a mental models approach

    National Research Council Canada - National Science Library

    Morgan, M. Granger (Millett Granger)

    2002-01-01

    ... information about risks. The procedure uses approaches from risk and decision analysis to identify the most relevant information; it also uses approaches from psychology and communication theory to ensure that its message is understood. This book is written in nontechnical terms, designed to make the approach feasible for anyone willing to try it. It is illustrat...

  8. Effective emergency management: reconsidering the bureaucratic approach.

    Science.gov (United States)

    Neal, D M; Phillips, B D

    1995-12-01

    The command and control approach is compared with the Emergent Human Resources Model (EHRM) approach to emergency management. Four decades of systematic research shows that a rigid, bureaucratic command and control approach to emergency management generally leads to an ineffective emergency response. Previous studies and our own research suggest that flexible, malleable, loosely coupled, organizational configurations can create a more effective disaster response.

  9. Nonlinear approaches in engineering applications 2

    CERN Document Server

    Jazar, Reza N

    2013-01-01

    Provides updated principles and applications of the nonlinear approaches in solving engineering and physics problems Demonstrates how nonlinear approaches may open avenues to better, safer, cheaper systems with less energy consumption Has a strong emphasis on the application, physical meaning, and methodologies of nonlinear approaches in different engineering and science problems

  10. The Rule-Assessment Approach and Education.

    Science.gov (United States)

    Siegler, Robert S.

    1982-01-01

    This paper describes the rule-assessment approach to cognitive development. The basic question that motivated the rule-assessment approach is how people's existing knowledge influences their ability to learn. Research using the rule-assessment approach is summarized in terms of eight conclusions, each illustrated with empirical examples.…

  11. A Hybrid Approach to Teaching Managerial Economics

    Science.gov (United States)

    Metzgar, Matthew

    2014-01-01

    Many institutions in higher education are experimenting with hybrid teaching approaches to undergraduate courses. Online resources may provide a number of advantages to students as compared to in-class approaches. Research regarding the effectiveness of hybrid approaches is mixed and still accumulating. This paper discusses the use of a hybrid…

  12. The dynamical systems approach to numerical integration

    Science.gov (United States)

    Wisdom, Jack

    2018-03-01

    The dynamical systems approach to numerical integration is reviewed and extended. The new method is compared to some alternative methods based on the Lie series approach. The test problem is the motion of the outer planets. The algorithms developed using the dynamical systems approach perform well.

  13. The Planets Approach to Migration Tools

    DEFF Research Database (Denmark)

    Zierau, Eld; van Wijk, Caroline

    2008-01-01

    This paper discusses the Planets approach to migration tool development. The approach consists of enhancing existing migration tools rather than developing tools from scratch. This pragmatic approach is based on the Planets view of the current situation for migration tools and two claims. The first...

  14. Statistical sampling approaches for soil monitoring

    NARCIS (Netherlands)

    Brus, D.J.

    2014-01-01

    This paper describes three statistical sampling approaches for regional soil monitoring, a design-based, a model-based and a hybrid approach. In the model-based approach a space-time model is exploited to predict global statistical parameters of interest such as the space-time mean. In the hybrid

  15. Anterior approach v. posterior approach - ultrasound-guided shoulder arthrogram injection

    Directory of Open Access Journals (Sweden)

    Merle Neethling-du Toit

    2008-03-01

    Full Text Available Anterior approach ultrasound guided arthrogram injections are a quick reliable way of injecting contrast prior to MRI scan. We did a retrospective study on patients, previously injected and scanned at our clinic, to compare the more manifested posterior approach with the anterior approach. The success rate for successful intra-articular injections for the anterior approach far outweighs the posterior approach. Also the anterior approach is more tolerable for patients as the injections are much quicker and seemingly less painful. In our knowledge it is thus far better to perform anterior approach shoulder arthrogram injections than posterior approach injections

  16. Two approaches to physics tutoring

    Science.gov (United States)

    Solomaniuck, Tania

    One in two first-year students at science or biomedical faculties fail in basic subjects such as mathematics, chemistry or physics. Course-specific tutoring is one of the available means for improving their performance. In the present research, two tutoring models are developed. Both incorporate independent learning, but from different perspectives and priorities. A pragmatic tutoring approach. The first part of the thesis describes the search process for an optimal course-specific tutoring strategy for a standard first-year physics course in life sciences curricula. After a number of empirical research rounds, a pragmatic compromise emerged as the most suitable form of tutoring. The approach is characterised by: (1) priority to questions from students; (2) a high degree of interactivity with the tutor and among students; (3) due consideration to the number of questions to be dealt with and the depth in which they should be discussed. Most students participating in the tutoring sessions expressed their satisfaction and performed sufficiently well in their exams. However, there was still a problem: the students' insight into the course material was restricted to first-order processing of the syllabus. While this would be satisfactory in non-scientific study programmes, it is deemed insufficient in programmes where deeper insight is required in order that students be able to deal adequately with new conceptual questions or problems. In-depth tutoring. In science programmes, the core objective is for students to acquire in-depth knowledge. Therefore, science educators are designing and studying teaching methods that are geared not only to the acquisition of in-depth knowledge as such, but also to the motivation of students to take a more in-depth approach to learning. Some of the crucial notions in their research are: the extent to which the course content ties in with students' prior knowledge, problem-setting strategies and concept-context linking. 'In

  17. A Novel Approach for Solving Semidefinite Programs

    Directory of Open Access Journals (Sweden)

    Hong-Wei Jiao

    2014-01-01

    Full Text Available A novel linearizing alternating direction augmented Lagrangian approach is proposed for effectively solving semidefinite programs (SDP. For every iteration, by fixing the other variables, the proposed approach alternatively optimizes the dual variables and the dual slack variables; then the primal variables, that is, Lagrange multipliers, are updated. In addition, the proposed approach renews all the variables in closed forms without solving any system of linear equations. Global convergence of the proposed approach is proved under mild conditions, and two numerical problems are given to demonstrate the effectiveness of the presented approach.

  18. Australia: Approaching an energy crossroads

    International Nuclear Information System (INIS)

    Falk, Jim; Settle, Domenica

    2011-01-01

    This paper considers energy policy in Australia in the context of its considerable energy resources, climate change and a recent change in government. It examines the possible paths that future energy use and policy in Australia could take, including published projections based largely on a 'business as usual' approach and projections based on a dramatic shift towards more efficient use of energy and renewable energy technologies. It also considers the various factors affecting future policy direction, including energy security, the advocacy in Australia for establishing nuclear electricity generation and other parts of the nuclear fuel-cycle, responses to climate change, and carbon sequestration. It concludes that while the Australian Government is currently reluctant to move away from a dependence on coal, and unlikely to adopt nuclear energy generation, a low-emissions future without waiting for the deployment of carbon capture and storage and without resorting to nuclear power is within reach. However, in the face of strong pressure from interest groups associated with energy intensive industry, making the necessary innovations will require further growth of community concern about climate change, and the development of greater understanding of the feasibility of employing low carbon-emissions options.

  19. Common approach to common interests

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2001-06-01

    In referring to issues confronting the energy field in this region and options to be exercised in the future, I would like to mention the fundamental condition of the utmost importance. That can be summed up as follows: any subject in energy area can never be solved by one country alone, given the geographical and geopolitical characteristics intrinsically possessed by energy. So, a regional approach is needed and it is especially necessary for the main players in the region to jointly address problems common to them. Though it may be a matter to be pursued in the distant future, I am personally dreaming a 'Common Energy Market for Northeast Asia,' in which member countries' interests are adjusted so that the market can be integrated and the region can become a most economically efficient market, thus formulating an effective power to encounter the outside. It should be noted that Europe needed forty years to integrate its market as the unified common market. It is necessary for us to follow a number of steps over the period to eventually materialize our common market concept, too. Now is the time for us to take a first step to lay the foundation for our descendants to enjoy prosperity from such a common market.

  20. The wonder approach to learning

    Directory of Open Access Journals (Sweden)

    Catherine eL'Ecuyer

    2014-10-01

    Full Text Available Wonder, innate in the child, is an inner desire to learn that awaits reality in order to be awakened. Wonder is at the origin of reality-based consciousness, thus of learning. The scope of wonder, which occurs at a metaphysical level, is greater than that of curiosity. Unfortunate misinterpretations of neuroscience have led to false brain-based ideas in the field of education, all of these based on the scientifically wrong assumption that children’s learning depends on an enriched environment. These beliefs have re-enforced the Behaviorist Approach to education and to parenting and have contributed to deadening our children’s sense of wonder. We suggest wonder as the center of all motivation and action in the child. Wonder is what makes life genuinely personal. Beauty is what triggers wonder. Wonder attunes to beauty through sensitivity and is unfolded by attachment. When wonder, beauty, sensitivity and secure attachment are present, learning is meaningful.On the contrary, when there is no volitional dimension involved (no wonder, no end or meaning (no beauty and no trusting predisposition (secure attachment, the rigid and limiting mechanical process of so-called learning through mere repetition become a deadening and alienating routine. This could be described as training, not as learning, because it does not contemplate the human being as a whole.