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Sample records for high-resolution temporal bone

  1. High resolution CT of temporal bone trauma

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    Youn, Eun Kyung [Korea General Hospital, Seoul (Korea, Republic of)

    1986-10-15

    Radiographic studies of the temporal bone following head trauma are indicated when there is cerebrospinal fluid otorrhea or rhinorrhoea, hearing loss, or facial nerve paralysis. Plain radiography displays only 17-30% of temporal bone fractures and pluridirectional tomography is both difficult to perform, particularly in the acutely ill patient, and less satisfactory for the demonstration of fine fractures. Consequently, high resolution CT is the imaging method of choice for the investigation of suspected temporal bone trauma and allows special resolution of fine bony detail comparable to that attainable by conventional tomography. Eight cases of temporal bone trauma examined at Korea General Hospital April 1985 through May 1986. The results were as follows: Seven patients (87%) suffered longitudinal fractures. In 6 patients who had purely conductive hearing loss, CT revealed various ossicular chain abnormality. In one patient who had neuro sensory hearing loss, CT demonstrated intract ossicular with a fracture nearing lateral wall of the lateral semicircular canal. In one patient who had mixed hearing loss, CT showed complex fracture.

  2. Clinically relevant human temporal bone measurements using novel high-resolution cone-beam CT

    Directory of Open Access Journals (Sweden)

    Jing Zou

    2017-03-01

    Conclusion: This novel high-resolution CBCT system has potentially broad applications in the diagnosis of inner ear disease and in monitoring associated pathological changes, surgical planning, navigation for the ear surgery, and temporal bone training.

  3. High-resolution computed tomography of the temporal bone. Part 2.: pathology; Kosc skroniowa w tomografii komputerowej wysokiej rozdzielczosci. Czesc 2.: patologia

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    Grzegorzewski, M.; Boron, Z.; Burzynska-Makuch, M. [Katedra i Zaklad Radiologii i Diagnostyki Narzadowej, Akademia Medyczna, Bydgoszcz (Poland)

    1995-12-31

    Selected cases of the temporal bone pathology on high resolution CT were demonstrated. Transverse and coronal sections of the cases were selected from 68 patients with various otological diseases. (author) 14 refs, 5 figs

  4. Nerve canals at the fundus of the internal auditory canal on high-resolution temporal bone CT

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    Ji, Yoon Ha; Youn, Eun Kyung; Kim, Seung Chul [Sungkyunkwan Univ., School of Medicine, Seoul (Korea, Republic of)

    2001-12-01

    To identify and evaluate the normal anatomy of nerve canals in the fundus of the internal auditory canal which can be visualized on high-resolution temporal bone CT. We retrospectively reviewed high-resolution (1 mm thickness and interval contiguous scan) temporal bone CT images of 253 ears in 150 patients who had not suffered trauma or undergone surgery. Those with a history of uncomplicated inflammatory disease were included, but those with symptoms of vertigo, sensorineural hearing loss, or facial nerve palsy were excluded. Three radiologists determined the detectability and location of canals for the labyrinthine segment of the facial, superior vestibular and cochlear nerve, and the saccular branch and posterior ampullary nerve of the inferior vestibular nerve. Five bony canals in the fundus of the internal auditory canal were identified as nerve canals. Four canals were identified on axial CT images in 100% of cases; the so-called singular canal was identified in only 68%. On coronal CT images, canals for the labyrinthine segment of the facial and superior vestibular nerve were seen in 100% of cases, but those for the cochlear nerve, the saccular branch of the inferior vestibular nerve, and the singular canal were seen in 90.1%, 87.4% and 78% of cases, respectiveIy. In all detectable cases, the canal for the labyrinthine segment of the facial nerve was revealed as one which traversed anterolateralIy, from the anterosuperior portion of the fundus of the internal auditory canal. The canal for the cochlear nerve was located just below that for the labyrinthine segment of the facial nerve, while that canal for the superior vestibular nerve was seen at the posterior aspect of these two canals. The canal for the saccular branch of the inferior vestibular nerve was located just below the canal for the superior vestibular nerve, and that for the posterior ampullary nerve, the so-called singular canal, ran laterally or posteolateralIy from the posteroinferior aspect of

  5. High-resolution computed tomography of the temporal bone. Part 1.: normal anatomy; Kosc skroniowa w tomografii komputerowej wysokiej rozdzielczosci. Czesc 1.: anatomia prawidlowa

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    Grzegorzewski, M.; Boron, Z.; Burzynska-Makuch, M. [Katedra i Zaklad Radiologii i Diagnostyki Narzadowej, Akademia Medyczna, Bydgoszcz (Poland)

    1995-12-31

    Normal anatomy of the temporal bone in transverse and coronal sections was presented. CT studies were performed using high-resolution program. The images of an asymptomatic ear of 2 patients were selected from 68 cases examined on account of various otological diseases. All the sections showed as many as 68 anatomic structures. (author) 5 refs, 2 figs

  6. High-resolution CT of temporal bone trauma: review of 38 cases; L'apport du scanner dans les traumatismes du rocher: a propos de 38 cas

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    Hiroual, M.R.; Zougarhi, A.; Cherif Idrissi El Ganouni, N.; Essadki, O.; Ousehal, A. [CHU Mohamed 6, Service de Radiologie, Marrakech (Morocco); Tijani Adil, O.; Maliki, O.; Aderdour, L.; Raji, A. [CHU Mohamed 6, Service d' ORL, Marrakech (Morocco)

    2010-01-15

    Purpose Temporal bone trauma is frequent but difficult to assess due to the diversity of clinical presentations and complex anatomy. We have sought to assess the different types of fractures and complications on high-resolution CT. Materials and methods Descriptive retrospective study over a 24 month period performed in the ENT radiology section of the Mohammed 6 university medical center in Marrakech. A total of 38 cases of temporal bone trauma were reviewed. All patients underwent ENT evaluation and high-resolution CT of the temporal bone using 1 mm axial and coronal sections. Results Mean patient age was 33 years (range: 14-55 years) with male predominance (sex ratio: 36/2). Clinical symptoms were mainly otorrhagia and conductive hearing loss. Oblique extra-labyrinthine fractures were most frequent. Two cases of pneumo-labyrinth were noted. Management was conservative in most cases with deafness in 3 cases. Conclusion High-resolution CT of the temporal bone provides accurate depiction of lesions explaining the clinical symptoms and helps guide management. MRI is complimentary to further assess the labyrinth and VII-VIII nerve complex. (author)

  7. Initial results of a new generation dual source CT system using only an in-plane comb filter for ultra-high resolution temporal bone imaging.

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    Meyer, Mathias; Haubenreisser, Holger; Raupach, Rainer; Schmidt, Bernhard; Lietzmann, Florian; Leidecker, Christianne; Allmendinger, Thomas; Flohr, Thomas; Schad, Lothar R; Schoenberg, Stefan O; Henzler, Thomas

    2015-01-01

    To prospectively evaluate radiation dose and image quality of a third generation dual-source CT (DSCT) without z-axis filter behind the patient for temporal bone CT. Forty-five patients were either examined on a first, second, or third generation DSCT in an ultra-high-resolution (UHR) temporal bone-imaging mode. On the third generation DSCT system, the tighter focal spot of 0.2 mm(2) removes the necessity for an additional z-axis-filter, leading to an improved z-axis radiation dose efficiency. Images of 0.4 mm were reconstructed using standard filtered-back-projection or iterative reconstruction (IR) technique for previous generations of DSCT and a novel IR algorithm for the third generation DSCT. Radiation dose and image quality were compared between the three DSCT systems. The statistically significantly highest subjective and objective image quality was evaluated for the third generation DSCT when compared to the first or second generation DSCT systems (all p generation examination as compared to the first and second generation DSCT. Temporal bone imaging without z-axis-UHR-filter and a novel third generation IR algorithm allows for significantly higher image quality while lowering effective dose when compared to the first two generations of DSCTs. • Omitting the z-axis-filter allows a reduction in radiation dose of 50% • A smaller focal spot of 0.2 mm (2) significantly improves spatial resolution • Ultra-high-resolution temporal-bone-CT helps to gain diagnostic information of the middle/inner ear.

  8. Evaluation of temporal bone pneumatization on high resolution CT (HRCT) measurements of the temporal bone in normal and otitis media group and their correlation to measurements of internal auditory meatus, vestibular or cochlear aqueduct

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    Nakamura, Miyako

    1988-07-01

    High resolution CT axial scans were made at the three levels of the temoral bone 91 cases. These cases consisted of 109 sides of normal pneumatization (NR group) and 73 of poor pneumatization resulted by chronic otitis (OM group). NR group included sensorineural hearing loss cases and/or sudden deafness on the side. Three levels of continuous slicing were chosen at the internal auditory meatus, the vestibular and the cochlear aqueduct, respectively. In each slice two sagittal and two horizontal measurements were done on the outer contour of the temporal bone. At the proper level, diameter as well as length of the internal acoustic meatus, the vestibular or the cochlear aqueduct were measured. Measurements of the temporal bone showed statistically significant difference between NR and OM groups. Correlation of both diameter and length of the internal auditory meatus to the temporal bone measurements were statistically significant. Neither of measurements on the vestibular or the cochlear aqueduct showed any significant correlation to that of the temporal bone.

  9. Initial results of a new generation dual source CT system using only an in-plane comb filter for ultra-high resolution temporal bone imaging

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    Meyer, Mathias; Haubenreisser, Holger; Schoenberg, Stefan O.; Henzler, Thomas [Heidelberg University, Institute of Clinical Radiology and Nuclear Medicine, University Medical Center Mannheim, Medical Faculty Mannheim, Mannheim (Germany); Raupach, Rainer; Schmidt, Bernhard; Leidecker, Christianne; Allmendinger, Thomas; Flohr, Thomas [Siemens Healthcare, Imaging and Therapy Division, Forchheim (Germany); Lietzmann, Florian; Schad, Lothar R. [Heidelberg University, Computer Assisted Clinical Medicine, University Medical Center Mannheim, Medical Faculty Mannheim, Mannheim (Germany)

    2015-01-15

    To prospectively evaluate radiation dose and image quality of a third generation dual-source CT (DSCT) without z-axis filter behind the patient for temporal bone CT. Forty-five patients were either examined on a first, second, or third generation DSCT in an ultra-high-resolution (UHR) temporal bone-imaging mode. On the third generation DSCT system, the tighter focal spot of 0.2 mm{sup 2} removesthe necessity for an additional z-axis-filter, leading to an improved z-axis radiation dose efficiency. Images of 0.4 mm were reconstructed using standard filtered-back-projection or iterative reconstruction (IR) technique for previous generations of DSCT and a novel IR algorithm for the third generation DSCT. Radiation dose and image quality were compared between the three DSCT systems. The statistically significantly highest subjective and objective image quality was evaluated for the third generation DSCT when compared to the first or second generation DSCT systems (all p < 0.05). Total effective dose was 63 %/39 % lower for the third generation examination as compared to the first and second generation DSCT. Temporal bone imaging without z-axis-UHR-filter and a novel third generation IR algorithm allows for significantly higher image quality while lowering effective dose when compared to the first two generations of DSCTs. (orig.)

  10. On temporal correlations in high-resolution frequency counting

    CERN Document Server

    Dunker, Tim; Rønningen, Ole Petter

    2016-01-01

    We analyze noise properties of time series of frequency data from different counting modes of a Keysight 53230A frequency counter. We use a 10 MHz reference signal from a passive hydrogen maser connected via phase-stable Huber+Suhner Sucoflex 104 cables to the reference and input connectors of the counter. We find that the high resolution gap-free (CONT) frequency counting process imposes long-term correlations in the output data, resulting in a modified Allan deviation that is characteristic of random walk phase noise. Equally important, the CONT mode results in a frequency bias. In contrast, the counter's undocumented raw continuous mode (RCON) yields unbiased frequency stability estimates with white phase noise characteristics, and of a magnitude consistent with the counter's 20 ps single-shot resolution. Furthermore, we demonstrate that a 100-point running average filter in conjunction with the RCON mode yields resolution enhanced frequency estimates with flicker phase noise characteristics. For instance,...

  11. SHEEP TEMPORAL BONE

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    Kesavan

    2016-03-01

    Full Text Available INTRODUCTION Human temporal bones are difficult to procure now a days due to various ethical issues. Sheep temporal bone is a good alternative due to morphological similarities, easy to procure and less cost. Many middle ear exercises can be done easily and handling of instruments is done in the procedures like myringoplasty, tympanoplasty, stapedotomy, facial nerve dissection and some middle ear implants. This is useful for resident training programme.

  12. Chondroblastoma of temporal bone

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    Tanohta, K.; Noda, M.; Katoh, H.; Okazaki, A.; Sugiyama, S.; Maehara, T.; Onishi, S.; Tanida, T.

    1986-07-01

    The case of a 55-year-old female with chondroblastoma arising from the left temporal bone is presented. Although 10 cases of temporal chondroblastoma have been reported, this is the first in which plain radiography, pluridirectional tomography, computed tomography (CT) and angiography were performed. We discuss the clinical and radiological aspects of this rare tumor.

  13. Virtual Temporal Bone Anatomy

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    Background The Visible Human Project(VHP) initiated by the U.S. National Library of Medicine has drawn much attention and interests from around the world. The Visible Chinese Human (VCH) project has started in China. The current study aims at acquiring a feasible virtual methodology for reconstructing the temporal bone of the Chinese population, which may provide an accurate 3-D model of important temporal bone structures that can be used in teaching and patient care for medical scientists and clinicians. Methods A series of sectional images of the temporal bone were generated from section slices of a female cadaver head. On each sectional image, SOIs (structures of interest) were segmented by carefully defining their contours and filling their areas with certain gray scale values. The processed volume data were then inducted into the 3D Slicer software(developed by the Surgical Planning Lab at Brigham and Women's Hospital and the MIT AI Lab) for resegmentation and generation of a set of tagged images of the SOIs. 3D surface models of SOIs were then reconstructed from these images. Results The temporal bone and structures in the temporal bone, including the tympanic cavity, mastoid cells, sigmoid sinus and internal carotid artery, were successfully reconstructed. The orientation of and spatial relationship among these structures were easily visualized in the reconstructed surface models. Conclusion The 3D Slicer software can be used for 3-dimensional visualization of anatomic structures in the temporal bone, which will greatly facilitate the advance of knowledge and techniques critical for studying and treating disorders involving the temporal bone.

  14. Imaging of inflammatory and infectious diseases in the temporal bone.

    NARCIS (Netherlands)

    Lemmerling, M.M.; Foer, B. De; Verbist, B.M.; Vyver, V. van de

    2009-01-01

    Inflammatory and infectious diseases of the temporal bone are a major indication to perform high-resolution CT and MR imaging studies. Such studies allow one to evaluate the extent of the disease in the soft tissues and in the bony structures of the temporal bone. On these same imaging studies the p

  15. Congenital malformations of the temporal bone.

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    Mukerji, Shraddha S; Parmar, Hemant A; Ibrahim, Mohannad; Mukherji, Suresh K

    2011-08-01

    Congenital ear or temporal bone malformations are a diagnostic challenge to radiologists and surgeons alike. Newer imaging techniques can detect subtle changes in middle ear and cochlear anatomy. This information is invaluable with increasing use of hearing restoration surgeries and/or cochlear implants in such patients. This article discusses the embryogenesis, classification system, and salient imaging findings of congenital outer, middle ear, and inner ear anomalies in children. Both high-resolution computerized tomography and magnetic resonance imaging scans of the temporal bones are described.

  16. Temporal bone imaging

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    Lemmerling, Marc [Algemeen Ziekenhuis Sint-Lucas, Gent (Belgium). Dept. of Radiology; Foer, Bert de (ed.) [Sint-Augustinus Ziekenhuis, Wilrijk (Belgium). Dept. of Radiology

    2015-04-01

    Complete overview of imaging of normal and diseased temporal bone. Straightforward structure to facilitate learning. Detailed consideration of newer imaging techniques, including the hot topic of diffusion-weighted imaging. Includes a chapter on anatomy that will be of great help to the novice interpreter of imaging findings. Excellent illustrations throughout. This book provides a complete overview of imaging of normal and diseased temporal bone. After description of indications for imaging and the cross-sectional imaging anatomy of the area, subsequent chapters address the various diseases and conditions that affect the temporal bone and are likely to be encountered regularly in clinical practice. The classic imaging methods are described and discussed in detail, and individual chapters are included on newer techniques such as functional imaging and diffusion-weighted imaging. There is also a strong focus on postoperative imaging. Throughout, imaging findings are documented with the aid of numerous informative, high-quality illustrations. Temporal Bone Imaging, with its straightforward structure based essentially on topography, will prove of immense value in daily practice.

  17. All-Optical Temporal Differentiator Using a High Resolution Optical Arbitrary Waveform Shaper

    Institute of Scientific and Technical Information of China (English)

    DONG Jian-Ji; LUO Bo-Wen; ZHANG Yin; LEI Lei; HUANG De-Xiu; ZHANG Xin-Liang

    2012-01-01

    We experimentally demonstrate an all-optical temporal differentiator using a high resolution optical arbitrary waveform shaper, which is based on liquid crystal on silicon switching elements, and both amplitude and phase of the spectrum are programmable. By designing specific transfer functions with the optical waveform shaper, we obtain first-, second-, and third-order differentiators for periodic pulses with small average errors. We also theoretically analyze the bandwidth limitation of optical waveform shaper on the differentiator.%We experimentally demonstrate an all-optical temporal differentiator using a high resolution optical arbitrary waveform shaper,which is based on liquid crystal on silicon switching elements,and both amplitude and phase of the spectrum are programmable.By designing specific transfer functions with the optical waveform shaper,we obtain first-,second-,and third-order differentiators for periodic pulses with small average errors.We also theoretically analyze the bandwidth limitation of optical waveform shaper on the differentiator.

  18. Temporal Bone Localized Chondroblastoma.

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    Demirhan, Hasan; Acioğlu, Engin; Durna, Yusuf Muhammed; Yiğit, Özgür; Bozkurt, Erol Rüştü; Karagöz, Yeşim

    2015-11-01

    Chondroblastoma is a highly destructive tumor originating from immature cartilage cells. Although chondroblastoma is defined as a benign tumor, it may exhibit malign tumor behaviors such as invasion or metastasis on neighboring structures. Magnetic resonance (MR) image is a solid mass lesion, which included heterogeneous hypointense in T2A and heterogeneous minimal hyperintense in T1A with destructive expansile characteristics and millimetric calcifications. Temporal bone chondroblastomas may complicate the diagnosis because of their different histologic characteristics. Microscopically, chondroblastic cell nests and calcification of locally "chicken wire" type around the cells are observed. These tumors secrete s-100 and vimentin and are used for differential diagnosis. In this study, a temporal bone localized chondroblastoma case is presented.

  19. Virtual temporal bone

    Institute of Scientific and Technical Information of China (English)

    QIU Ming-guo; ZHANG Shao-xiang; LIU Zheng-jin; TAN Li-wen; WANG Yu-su; DENG Jun-hui; TANG Ze-sheng

    2002-01-01

    Objective:To provide the virtual model of the temporal bone for improving 3-dimension (3D) visualization of the inner ear. Methods: Plastination technique was used to make equidistant serial thin sections 1.0 mm in thickness. On SGI workstation, a Contours+Marching Cubes algorithm was selected to reconstruct the temporal bone and intratemporal structures in 3D, then to view the middle ear, inner ear, and intratemporal structures which imitate the scenes observed by the traditional endoscopy. Results: The virtual model of the temporal bone was successfully constructed, with all reconstructed structures being represented individually or jointly and being rotated continuously in any plane. Virtual endoscopy improved 3D visualization of the middle ear, inner ear, and intratemporal structures. Conclusion: The reconstructed model can be used for the medical students to rehearse or review the surgeries on this part and for the surgeons to develop a new approach for operation. Virtual otoscopy stands as a promising new visualization technique for elucidating the structure and relation of the middle ear, inner ear, and intratemporal structures.

  20. Bone Structure and Estimated Bone Strength in Obese Patients Evaluated by High-Resolution Peripheral Quantitative Computed Tomography

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    Andersen, Stine; Frederiksen, Katrine Diemer; Hansen, Stinus;

    2014-01-01

    Obesity is associated with high bone mineral density (BMD), but whether obesity-related higher bone mass increases bone strength and thereby protect against fractures is uncertain. We estimated effects of obesity on bone microarchitecture and estimated strength in 36 patients (12 males and 24...... females, age 25-56 years and BMI 33.2-57.6 kg/m(2)) matched with healthy controls (age 25-54 years and BMI 19.5-24.8 kg/m(2)) in regard to gender, menopausal status, age (±6 years) and height (±6 cm) using high resolution peripheral quantitative computed tomography and dual energy X-ray absorptiometry...

  1. High Resolution Peripheral Quantitative Computed Tomography for Assessment of Bone Quality

    Science.gov (United States)

    Kazakia, Galateia

    2014-03-01

    The study of bone quality is motivated by the high morbidity, mortality, and societal cost of skeletal fractures. Over 10 million people are diagnosed with osteoporosis in the US alone, suffering 1.5 million osteoporotic fractures and costing the health care system over 17 billion annually. Accurate assessment of fracture risk is necessary to ensure that pharmacological and other interventions are appropriately administered. Currently, areal bone mineral density (aBMD) based on 2D dual-energy X-ray absorptiometry (DXA) is used to determine osteoporotic status and predict fracture risk. Though aBMD is a significant predictor of fracture risk, it does not completely explain bone strength or fracture incidence. The major limitation of aBMD is the lack of 3D information, which is necessary to distinguish between cortical and trabecular bone and to quantify bone geometry and microarchitecture. High resolution peripheral quantitative computed tomography (HR-pQCT) enables in vivo assessment of volumetric BMD within specific bone compartments as well as quantification of geometric and microarchitectural measures of bone quality. HR-pQCT studies have documented that trabecular bone microstructure alterations are associated with fracture risk independent of aBMD.... Cortical bone microstructure - specifically porosity - is a major determinant of strength, stiffness, and fracture toughness of cortical tissue and may further explain the aBMD-independent effect of age on bone fragility and fracture risk. The application of finite element analysis (FEA) to HR-pQCT data permits estimation of patient-specific bone strength, shown to be associated with fracture incidence independent of aBMD. This talk will describe the HR-pQCT scanner, established metrics of bone quality derived from HR-pQCT data, and novel analyses of bone quality currently in development. Cross-sectional and longitudinal HR-pQCT studies investigating the impact of aging, disease, injury, gender, race, and

  2. A study with high resolution computed tomography of bone destruction in cholesteatoma

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    Kikuchi, Shigeru; Yamaso, Tatsuya; Higo, Ryusaburo (Kameda General Hospital, Kamogawa, Chiba (Japan)); Senba, Tetsuo; Iinuma, Yoshitaka

    1992-07-01

    The modes and incidences of bone destruction in the middle ear cholesteatoma were evaluated by high resolution computed tomography, comparing with chronic otitis media with central perforation (COM) as control. The head of the malleus, the body and long process of the incus were more markedly destroyed in cholesteatoma than in COM with statistical significance. With the further extension of cholesteatoma into the antrum, the tegmen of the aditus ad antrum, the lateral semicircular canal, the handle of the malleus and the Korner's septum were involved in bone destruction. (author).

  3. [High resolution peripheral quantitative computed tomography for the assessment of morphological and mechanical bone parameters].

    Science.gov (United States)

    Fuller, Henrique; Fuller, Ricardo; Pereira, Rosa Maria R

    2015-01-01

    High resolution peripheral quantitative computed tomography (HR-pQCT) is a new technology commercially available for less than 10 years that allows performing in vivo assessment of bone parameters. HR-pQCT assesses the trabecular thickness, trabecular separation, trabecular number and connectivity density and, in addition, cortical bone density and thickness and total bone volume and density in high-definition mode, which additionally allows obtaining digital constructs of bone microarchitecture. The application of mathematics to captured data, a method called finite element analysis (FEA), allows the estimation of the physical properties of the tissue, simulating supported loads in a non-invasive way. Thus, HR-pQCT simultaneously acquires data previously provided separately by dual energy x-ray absorptiometry (DXA), magnetic resonance imaging and histomorphometry, aggregating biomechanical estimates previously only possible in extracted tissues. This method has a satisfactory reproducibility, with coefficients of variation rarely exceeding 3%. Regarding accuracy, the method shows a fair to good agreement (r(2) = 0.37-0.97). The main clinical application of this method is in the quantification and monitoring of metabolic bone disorders, more fully evaluating bone strength and fracture risk. In rheumatoid arthritis patients, this allows gauging the number and size of erosions and cysts, in addition to joint space. In osteoarthritis, it is possible to characterize the bone marrow edema-like areas that show a correlation with cartilage breakdown. Given its high cost, HR-pQCT is still a research tool, but the high resolution and efficiency of this method reveal advantages over the methods currently used for bone assessment, with a potential to become an important tool in clinical practice. Copyright © 2014 Elsevier Editora Ltda. All rights reserved.

  4. Pulmonary infections following bone marrow transplantation: High-resolution CT findings in 35 paediatric patients

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    Davaus Gasparetto, Taisa [Department of Diagnostic Radiology of the Federal Universitie Fluminense, Niteroi (Brazil); Federal University of Rio de Janeiro, Rio de Janeiro (Brazil)], E-mail: taisadavaus@gmail.com; Escuissato, Dante L. [Department of Diagnostic Radiology of the University of Parana, Curitiba (Brazil); Marchiori, Edson [Department of Diagnostic Radiology of the Federal Universitie Fluminense, Niteroi (Brazil); Federal University of Rio de Janeiro, Rio de Janeiro (Brazil)

    2008-04-15

    Purpose: The purpose of this study was to assess the high-resolution CT findings of paediatric patients who had pulmonary infections following bone marrow transplantation (BMT), and to evaluate the differential diagnosis through high-resolution CT of the various pathogens responsible for pulmonary infections after BMT. Patients and methods: The study included 35 consecutive patients who had documented pulmonary infection, high-resolution CT of the chest performed within 24 h of the beginning of symptoms, and proven diagnosis within 1 week of the onset of symptoms. The pulmonary infections were due to viruses (n = 16), bacteria (n = 9), fungi (n = 9), and protozoa (n = 1). Two radiologists analyzed the CT scans and reached final decisions regarding the findings by consensus. Results: Four patients with confirmed pneumonia had normal high-resolution CT scans. Regarding the viral infections, the most frequent features were areas of ground-glass attenuation (43.7%) and small centrilobular nodules (31.2%). Airspace consolidation (88.9%), small centrilobular nodules (22.2%) and ground-glass attenuation (22.2%) were the most frequent findings in patients with bacterial pneumonia following BMT. Large nodules were seen in 66.7% of the patients with fungal pneumonia, and in only one case of virus infection. The 'halo sign' (n = 5) was seen only in patients with fungal pneumonia. Conclusion: In conclusion, the main causes of pulmonary infection in paediatric patients following BMT share similar high-resolution CT findings. Large nodules and 'halo sign' are more common in patients with fungal infections.

  5. Ivory Osteoma Of Temporal Bone

    Directory of Open Access Journals (Sweden)

    Ravi Meher

    2006-03-01

    Full Text Available Osteomas are slow growing bony tumors common in fronto-ethmoid regions and rare in temporal bone. These are usually asymptomatic and require treatment mainly for cosmetic reasons. We describe a case of temporal bone osteoma in a female.

  6. A hyper-temporal remote sensing protocol for high-resolution mapping of ecological sites.

    Science.gov (United States)

    Maynard, Jonathan J; Karl, Jason W

    2017-01-01

    ) spectral variability through time, 2) field sampling protocols that accurately characterize key soil properties (e.g., texture, depth) need to be adopted, and 3) additional environmental covariates (e.g. terrain attributes) need to be evaluated that may help further differentiate sites with similar spectral signals. Finally, the proposed hyper-temporal remote sensing framework may provide a standardized approach to evaluate and test our ecological site concepts through examining differences in vegetation dynamics in response to climatic variability and other drivers of land-use change. Results from this study demonstrate the efficacy of the hyper-temporal remote sensing approach for high resolution mapping of ecological sites, and highlights its utility in terms of reduced cost and time investment relative to traditional manual mapping approaches.

  7. Agro-hydrology and multi temporal high resolution remote sensing: toward an explicit spatial processes calibration

    Science.gov (United States)

    Ferrant, S.; Gascoin, S.; Veloso, A.; Salmon-Monviola, J.; Claverie, M.; Rivalland, V.; Dedieu, G.; Demarez, V.; Ceschia, E.; Probst, J.-L.; Durand, P.; Bustillo, V.

    2014-07-01

    The recent and forthcoming availability of high resolution satellite image series offers new opportunities in agro-hydrological research and modeling. We investigated the perspective offered by improving the crop growth dynamic simulation using the distributed agro-hydrological model, Topography based Nitrogen transfer and Transformation (TNT2), using LAI map series derived from 105 Formosat-2 (F2) images during the period 2006-2010. The TNT2 model (Beaujouan et al., 2002), calibrated with discharge and in-stream nitrate fluxes for the period 1985-2001, was tested on the 2006-2010 dataset (climate, land use, agricultural practices, discharge and nitrate fluxes at the outlet). A priori agricultural practices obtained from an extensive field survey such as seeding date, crop cultivar, and fertilizer amount were used as input variables. Continuous values of LAI as a function of cumulative daily temperature were obtained at the crop field level by fitting a double logistic equation against discrete satellite-derived LAI. Model predictions of LAI dynamics with a priori input parameters showed an temporal shift with observed LAI profiles irregularly distributed in space (between field crops) and time (between years). By re-setting seeding date at the crop field level, we proposed an optimization method to minimize efficiently this temporal shift and better fit the crop growth against the spatial observations as well as crop production. This optimization of simulated LAI has a negligible impact on water budget at the catchment scale (1 mm yr-1 in average) but a noticeable impact on in-stream nitrogen fluxes (around 12%) which is of interest considering nitrate stream contamination issues and TNT2 model objectives. This study demonstrates the contribution of forthcoming high spatial and temporal resolution products of Sentinel-2 satellite mission in improving agro-hydrological modeling by constraining the spatial representation of crop productivity.

  8. Pan-Tropical Forest Mapping by Exploiting Textures of Multi-Temporal High Resolution SAR Data

    Science.gov (United States)

    Knuth, R.; Eckardt, R.; Richter, N.; Schmullius, C.

    2012-12-01

    radar images were processed using an operational processing chain that includes radiometric transformation, noise reduction, and georeferencing of the SAR data. In places with pronounced topography both satellites were used as single pass interferometer to derive a digital surface model in order to perform an orthorectification followed by a topographic normalization of the SAR backscatter values. As prescribed by the FAO, the final segment-based classification algorithm was fed by multi-temporal backscatter information, a set of textural features, and information on the degree of coherence between the multi-temporal acquisitions. Validation with available high resolution optical imagery suggests that the produced forest maps possess an overall accuracy of 75 percent or higher.

  9. Determination of Destructed and Infracted Forest Areas with Multi-temporal High Resolution Satellite Images

    Science.gov (United States)

    Seker, D. Z.; Unal, A.; Kaya, S.; Alganci, U.

    2015-12-01

    Migration from rural areas to city centers and their surroundings is an important problem of not only our country but also the countries that under development stage. This uncontrolled and huge amount of migration brings out urbanization and socio - economic problems. The demand on settling the industrial areas and commercial activities nearby the city centers results with a negative change in natural land cover on cities. Negative impacts of human induced activities on natural resources and land cover has been continuously increasing for decades. The main human activities that resulted with destruction and infraction of forest areas can be defined as mining activities, agricultural activities, industrial / commercial activities and urbanization. Temporal monitoring of the changes in spatial distribution of forest areas is significantly important for effective management and planning progress. Changes can occur as spatially large destructions or small infractions. Therefore there is a need for reliable, fast and accurate data sources. At this point, satellite images proved to be a good data source for determination of the land use /cover changes with their capability of monitoring large areas with reasonable temporal resolutions. Spectral information derived from images provides discrimination of land use/cover types from each other. Developments in remote sensing technology in the last decade improved the spatial resolution of satellites and high resolution images were started to be used to detect even small changes in the land surface. As being the megacity of Turkey, Istanbul has been facing a huge migration for the last 20 years and effects of urbanization and other human based activities over forest areas are significant. Main focus of this study is to determine the destructions and infractions in forest areas of Istanbul, Turkey with 2.5m resolution SPOT 5 multi-temporal satellite imagery. Analysis was mainly constructed on threshold based classification of

  10. Spatial-temporal fractions verification for high-resolution ensemble forecasts

    Directory of Open Access Journals (Sweden)

    Le Duc

    2013-04-01

    Full Text Available Experiments with two ensemble systems of resolutions 10 km (MF10km and 2 km (MF2km were designed to examine the value of cloud-resolving ensemble forecast in predicting precipitation on small spatio-temporal scales. Since the verification was performed on short-term precipitation at high resolution, uncertainties from small-scale processes caused the traditional verification methods to be inconsistent with the subjective evaluation. An extended verification method based on the Fractions Skill Score (FSS was introduced to account for these uncertainties. The main idea is to extend the concept of spatial neighbourhood in FSS to the time and ensemble dimension. The extension was carried out by recognising that even if ensemble forecast is used, small-scale variability still exists in forecasts and influences verification results. In addition to FSS, the neighbourhood concept was also incorporated into reliability diagrams and relative operating characteristics to verify the reliability and resolution of two systems. The extension of FSS in time dimension demonstrates the important role of temporal scales in short-term precipitation verification at small spatial scales. The extension of FSS in ensemble space is called the ensemble FSS, which is a good representative of FSS for ensemble forecast in comparison with the FSS of ensemble mean. The verification results show that MF2km outperforms MF10km in heavy rain forecasts. In contrast, MF10km was slightly better than MF2km in predicting light rains, suggesting that the horizontal resolution of 2 km is not necessarily enough to completely resolve convective cells.

  11. Comparative Study of Temporal Bone High-resolution CT and Intra-operative Findings in Patients with Traumatic Facial Nerve Paralysis%外伤性面瘫患者的颞骨高分辨率CT表现及其术中对照研究

    Institute of Scientific and Technical Information of China (English)

    袁辉; 金延方; 岳云龙; 李健东; 赵亮

    2013-01-01

    Purpose To investigate the value of the temporal bone high-resolution CT (HRCT) in traumatic facial paralysis. Materials and Methods HRCT with cross-sectional scanning and multi-planar reformation (MPR) was applied to 21 ears in patients with traumatic facial paralysis, and the imaging manifestations were retrospectively analyzed according to the surgical results. Results In the 21 ears, there were 15 ears with longitudinal fractures, 3 ears with transverse fractures, 3 ears with mixed type. 32 segments of facial nerve canal involvement were observed on HRCT, fracture involved in the facial nerve canal and the tympanic segment of the geniculate ganglion segment in 8 ears, only involved in the geniculate ganglion segment in 8 ears, involved in the labyrinthine segment and the geniculate ganglion segment in 2 ears, only involved in the tympanic segment in 1 ear, involved in the labyrinthine segment 1 ear, and the tympanic segment and after knee segment involvement 1 ear. 49 segments of facial nerve were involved in surgery. Compared with surgical results, HRCT had the full agreement with all segments involvement in 3 ears (3/21), 1 segment involvement in 10 ears (10/21), 2 segments involvement in 8 ears (8/21). Conclusion Temporal bone HRCT can underestimate the extent of damage, and provide important information for the clinical treatment of traumatic paralysis. However, HRCT will underestimate the damage extent of facial nerve canal compared with the surgical results, especially in post-knee segment and mastoid segment damage.%  目的探讨颞骨高分辨率CT(HRCT)在外伤性面瘫中的应用价值。资料与方法对外伤性面瘫患者的21侧耳行HRCT横断面扫描及多平面重组(MPR),对照其手术结果回顾性分析影像学表现。结果21耳中,纵行骨折15耳,横行骨折3耳,混合型3耳。HRCT共显示32段面神经管受累,其中,骨折同时累及面神经管膝状神经节段及鼓室段8耳,

  12. Osteoradionecrosois of the temporal bone

    Energy Technology Data Exchange (ETDEWEB)

    Thornley, G.D.; Gullane, P.J.; Ruby, R.R.; Heeneman, H.

    1979-10-01

    Six cases of osteoradionecrosis of the temporal bone are described. Persistent symptoms of otitis externa refractory to local treatment measures should alert the physician to the possibility of underlying osteoradionecrosis. Treatment of superficial parotidectomy and partial temporal bone resection with preservation of the facial nerve is indicated if local aggressive conservative measures fail to control the disease. Benign mixed tumors of the parotid gland should be treated surgically with avoidance of radiotherapy.

  13. The Impact of Horizontal and Temporal Resolution on Convection and Precipitation with High-Resolution GEOS-5

    Science.gov (United States)

    Putman, William P.

    2012-01-01

    Using a high-resolution non-hydrostatic version of GEOS-5 with the cubed-sphere finite-volume dynamical core, the impact of spatial and temporal resolution on cloud properties will be evaluated. There are indications from examining convective cluster development in high resolution GEOS-5 forecasts that the temporal resolution within the model may playas significant a role as horizontal resolution. Comparing modeled convective cloud clusters versus satellite observations of brightness temperature, we have found that improved. temporal resolution in GEOS-S accounts for a significant portion of the improvements in the statistical distribution of convective cloud clusters. Using satellite simulators in GEOS-S we will compare the cloud optical properties of GEOS-S at various spatial and temporal resolutions with those observed from MODIS. The potential impact of these results on tropical cyclone formation and intensity will be examined as well.

  14. Temporal bone squamous cell carcinoma - Penang experience.

    Science.gov (United States)

    Ng, S Y; Pua, K C; Zahirrudin, Z

    2015-12-01

    Temporal bone squamous cell carcinoma (TBSCC) is rare and poses difficulties in diagnosing, staging and management. We describe a case series with six patients who were diagnosed TBSCC, from January 2009 to June 2014, with median age of 62 years old. All patients presented with blood-stain discharge and external auditory canal mass, showing that these findings should highly alert the diagnosis of TBSCC. Three patients staged T3 and another three with T4 disease. High-resolution CT (HRCT) temporal findings were noted to be different from intraoperative findings and therefore we conclude that MRI should be done to look for middle ear involvement or other soft tissue invasion for more accurate staging. Lateral temporal bone resection (LTBR) and parotidectomy was done for four patients with or without neck dissection. Patients with positive margin, perineural invasion or parotid and glenoid involvement carry poorer prognosis and postoperative radiotherapy may improve the survival rate. One patient had successful tumor resection via piecemeal removal approach in contrast with the recommended en bloc resection shows that with negative margin achieved, piecemeal removal approach can be a good option for patients with T2-3 disease. In general, T4 tumor has dismal outcome regardless of surgery or radiotherapy given.

  15. Decoding Overlapping Memories in the Medial Temporal Lobes Using High-Resolution fMRI

    Science.gov (United States)

    Chadwick, Martin J.; Hassabis, Demis; Maguire, Eleanor A.

    2011-01-01

    The hippocampus is proposed to process overlapping episodes as discrete memory traces, although direct evidence for this in human episodic memory is scarce. Using green-screen technology we created four highly overlapping movies of everyday events. Participants were scanned using high-resolution fMRI while recalling the movies. Multivariate…

  16. A Novel Temporal Bone Simulation Model Using 3D Printing Techniques.

    Science.gov (United States)

    Mowry, Sarah E; Jammal, Hachem; Myer, Charles; Solares, Clementino Arturo; Weinberger, Paul

    2015-09-01

    An inexpensive temporal bone model for use in a temporal bone dissection laboratory setting can be made using a commercially available, consumer-grade 3D printer. Several models for a simulated temporal bone have been described but use commercial-grade printers and materials to produce these models. The goal of this project was to produce a plastic simulated temporal bone on an inexpensive 3D printer that recreates the visual and haptic experience associated with drilling a human temporal bone. Images from a high-resolution CT of a normal temporal bone were converted into stereolithography files via commercially available software, with image conversion and print settings adjusted to achieve optimal print quality. The temporal bone model was printed using acrylonitrile butadiene styrene (ABS) plastic filament on a MakerBot 2x 3D printer. Simulated temporal bones were drilled by seven expert temporal bone surgeons, assessing the fidelity of the model as compared with a human cadaveric temporal bone. Using a four-point scale, the simulated bones were assessed for haptic experience and recreation of the temporal bone anatomy. The created model was felt to be an accurate representation of a human temporal bone. All raters felt strongly this would be a good training model for junior residents or to simulate difficult surgical anatomy. Material cost for each model was $1.92. A realistic, inexpensive, and easily reproducible temporal bone model can be created on a consumer-grade desktop 3D printer.

  17. Temporal Dynamics of Motivation-Cognitive Control Interactions Revealed by High-Resolution Pupillometry

    OpenAIRE

    Chiew, Kimberly S.; Braver, Todd S.

    2013-01-01

    Motivational manipulations, such as the presence of performance-contingent reward incentives, can have substantial influences on cognitive control. Previous evidence suggests that reward incentives may enhance cognitive performance specifically through increased preparatory, or proactive, control processes. The present study examined reward influences on cognitive control dynamics in the AX-Continuous Performance Task (AX-CPT), using high-resolution pupillometry. In the AX-CPT, contextual cue...

  18. High resolution CT in the investigation of bone destruction in the outer ear

    Energy Technology Data Exchange (ETDEWEB)

    Koester, O.; Straehler-Pohl, H.J.

    1986-12-01

    Eleven patients with known malignant tumours of the outer ear and three patients with otitis externa maligna were examined by high resolution CT. CT provided accurate information concerning soft tissue infiltration into the parotid or subtemporal tissues, and of the bony destruction in the mastoid, meatus and tympanic cavity. Absolute differentiation between a malignant tumour and otitis cisterna maligna is not possible, not even by high resolution CT.

  19. Automated simulation of areal bone mineral density assessment in the distal radius from high-resolution peripheral quantitative computed tomography

    OpenAIRE

    Burghardt, A. J.; Kazakia, G. J.; Link, T.M.; Majumdar, S

    2009-01-01

    Summary An automated image processing method is presented for simulating areal bone mineral density measures using high-resolution peripheral quantitative computed tomography (HR-pQCT) in the ultra-distal radius. The accuracy of the method is validated against clinical dual X-ray absorptiometry (DXA). This technique represents a useful reference to gauge the utility of novel 3D quantification methods applied to HR-pQCT in multi-center clinical studies and potentially negates the need for sepa...

  20. Quantification of Deltaic Coastal Zone Change Based on Multi-Temporal High Resolution Earth Observation Techniques

    Directory of Open Access Journals (Sweden)

    Emmanuel Vassilakis

    2014-01-01

    Full Text Available A series of methodologies are described in this paper aiming to quantify the natural hazard due to the coastal changes at a deltaic fan. The coastline of Istiaia (North Evia, Greece has been chosen for this study as several areas of accretion and erosion have been identified during the past few decades. We combined different types of datasets, extracted from high resolution panchromatic aerial photographs and traced the contemporary shoreline by high accuracy surveying with Real Time Kinematics (RTK GPS equipment. The interpretation of all shorelines required geo-statistical analysis in a Geographical Information System. A large number of high resolution morphological sections were constructed normally to the coast, revealing erosional and depositional parts of the beach. Retreating and extension rates were calculated for each section reaching the values of 0.98 m/yr and 1.36 m/yr, respectively. The results proved to be very accurate, allowing us to expand the developed methodology by using more complete time-series of remote sensing datasets along with more frequent RTK-GPS surveying.

  1. Evaluation of high resolution spatio-temporal precipitation extremes from a stochastic weather generator

    DEFF Research Database (Denmark)

    Sørup, Hjalte Jomo Danielsen; Christensen, O. B.; Arnbjerg-Nielsen, Karsten

    Spatio-temporal rainfall is modelled for the North-Eastern part of Zealand (Denmark) using the Spatio-Temporal Neyman-Scott Rectangular Pulses model as implemented in the RainSim software. Hourly precipitation series for fitting the model are obtained from a dense network of tipping bucket rain g...

  2. Evaluation of high resolution spatio-temporal precipitation extremes from a stochastic weather generator

    DEFF Research Database (Denmark)

    Sørup, Hjalte Jomo Danielsen; Christensen, O. B.; Arnbjerg-Nielsen, Karsten;

    Spatio-temporal rainfall is modelled for the North-Eastern part of Zealand (Denmark) using the Spatio-Temporal Neyman-Scott Rectangular Pulses model as implemented in the RainSim software. Hourly precipitation series for fitting the model are obtained from a dense network of tipping bucket rain g...

  3. Exploiting Temporal Context in High-Resolution Movement-Related EEG Classification

    OpenAIRE

    2011-01-01

    The contribution presents an application of a movement-related EEG temporal development classification which improves the classification score of voluntary movements controlled by closely localized regions of the brain. A dynamic Hidden Markov Model-based (HMM) classifier specifically designed to capture EEG temporal behavior was used. Surprisingly, HMM classifiers are rarely used for BCI design despite of their advantages. Because of this we also experimented with Learning Vector Quantizatio...

  4. The evolution of active Lavina di Roncovetro landslides by multi-temporal high-resolution topographic data

    Science.gov (United States)

    Isola, Ilaria; Fornaciai, Alessandro; Favalli, Massimiliano; Gigli, Giovanni; Nannipieri, Luca; Mucchi, Lorenzo; Intrieri, Emanuele; Pizziolo, Marco; Bertolini, Giovanni; Trippi, Federico; Casagli, Nicola; Schina, Rosa; Carnevale, Ennio

    2017-04-01

    High-resolution topographic data has been collected over the Lavina di Roncovetro active landslide (Reggio Emilia, Italy) for about 3 years by using various methods and technologies. Tha Lavina di Roncovetro landslide can be considered as a fluid-viscous mudflow, which can reach a down flow maximum rate of 10 m/day. The landslide started between the middle and the end of the XIX century and since then it has had a rapid evolution mainly characterized by the rapid retrogression of the crown to the extent that now reaches the top of Mount Staffola. In the frame of EU Wireless Sensor Network for Ground Instability Monitoring - Wi-GIM project (LIFE12ENV/IT/001033) the Lavina di Roncovetro landslide has been periodically tracked using technologies that span from the LiDAR, both terrestrial and aerial, to the Structure from Motion (SfM) photogrammetry method based on Unmanned Aerial Vehicle (UAV) and aerial survey. These data are used to create six high-resolution Digital Terrain Models (DEMs), which imaged the landslide surface on March 2014, October 2014, June 2015, July 2015, January 2016 and December 2016. Multi-temporal high-resolution topographic data have been used for qualitative and quantitative morphometric analysis and topographic change detection of the landslide with the aim to estimate and map the volume of removed and/or accumulated material, the average rates of vertical and horizontal displacement and the deformation structures affecting the landslide over the investigated period.

  5. Visual short-term memory for high resolution associations is impaired in patients with medial temporal lobe damage.

    Science.gov (United States)

    Koen, Joshua D; Borders, Alyssa A; Petzold, Michael T; Yonelinas, Andrew P

    2017-02-01

    The medial temporal lobe (MTL) plays a critical role in episodic long-term memory, but whether the MTL is necessary for visual short-term memory is controversial. Some studies have indicated that MTL damage disrupts visual short-term memory performance whereas other studies have failed to find such evidence. To account for these mixed results, it has been proposed that the hippocampus is critical in supporting short-term memory for high resolution complex bindings, while the cortex is sufficient to support simple, low resolution bindings. This hypothesis was tested in the current study by assessing visual short-term memory in patients with damage to the MTL and controls for high resolution and low resolution object-location and object-color associations. In the location tests, participants encoded sets of two or four objects in different locations on the screen. After each set, participants performed a two-alternative forced-choice task in which they were required to discriminate the object in the target location from the object in a high or low resolution lure location (i.e., the object locations were very close or far away from the target location, respectively). Similarly, in the color tests, participants were presented with sets of two or four objects in a different color and, after each set, were required to discriminate the object in the target color from the object in a high or low resolution lure color (i.e., the lure color was very similar or very different, respectively, to the studied color). The patients were significantly impaired in visual short-term memory, but importantly, they were more impaired for high resolution object-location and object-color bindings. The results are consistent with the proposal that the hippocampus plays a critical role in forming and maintaining complex, high resolution bindings. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

  6. High-resolution-cone beam tomography analysis of bone microarchitecture in patients with acromegaly and radiological vertebral fractures.

    Science.gov (United States)

    Maffezzoni, Filippo; Maddalo, Michele; Frara, Stefano; Mezzone, Monica; Zorza, Ivan; Baruffaldi, Fabio; Doglietto, Francesco; Mazziotti, Gherardo; Maroldi, Roberto; Giustina, Andrea

    2016-11-01

    Vertebral fractures are an emerging complication of acromegaly but their prediction is still difficult occurring even in patients with normal bone mineral density. In this study we evaluated the ability of high-resolution cone-beam computed tomography to provide information on skeletal abnormalities associated with vertebral fractures in acromegaly. 40 patients (24 females, 16 males; median age 57 years, range 25-72) and 21 healthy volunteers (10 females, 11 males; median age 60 years, range: 25-68) were evaluated for trabecular (bone volume/trabecular volume ratio, mean trabecular separation, and mean trabecular thickness) and cortical (thickness and porosity) parameters at distal radius using a high-resolution cone-beam computed tomography system. All acromegaly patients were evaluated for morphometric vertebral fractures and for mineral bone density by dual-energy X-ray absorptiometry at lumbar spine, total hip, femoral neck, and distal radius. Acromegaly patients with vertebral fractures (15 cases) had significantly (p cone-beam computed tomography at the distal radius may be useful to evaluate and predict the effects of acromegaly on bone microstructure.

  7. Exploiting Temporal Context in High-Resolution Movement-Related EEG Classification

    Directory of Open Access Journals (Sweden)

    J. Dolezal

    2011-09-01

    Full Text Available The contribution presents an application of a movement-related EEG temporal development classification which improves the classification score of voluntary movements controlled by closely localized regions of the brain. A dynamic Hidden Markov Model-based (HMM classifier specifically designed to capture EEG temporal behavior was used. Surprisingly, HMM classifiers are rarely used for BCI design despite of their advantages. Because of this we also experimented with Learning Vector Quantization, Perceptron, and Support Vector Machine classifiers using a feature space which captures the temporal dynamics of the data. The results presented in this work show that HMM achieves the best performance due to an a priori information on physiological behavior of EEG inserted to the HMM classifier. Feature extraction process and problems with classification were analyzed as well. Classification scores of 66.7% – 94.7% were achieved in our experiments.

  8. Multi-temporal high resolution monitoring of debris-covered glaciers using unmanned aerial vehicles

    Science.gov (United States)

    Kraaijenbrink, Philip; Immerzeel, Walter; de Jong, Steven; Shea, Joseph; Pellicciotti, Francesca; Meijer, Sander; Shresta, Arun

    2016-04-01

    Debris-covered glaciers in the Himalayas are relatively unstudied due to the difficulties in fieldwork caused by the inaccessible terrain and the presence of debris layers, which complicate in situ measurements. To overcome these difficulties an unmanned aerial vehicle (UAV) has been deployed multiple times over two debris covered glaciers in the Langtang catchment, located in the Nepalese Himalayas. Using differential GPS measurements and the Structure for Motion algorithm the UAV imagery was processed into accurate high-resolution digital elevation models and orthomosaics for both pre- and post-monsoon periods. These data were successfully used to estimate seasonal surface flow and mass wasting by using cross-correlation feature tracking and DEM differencing techniques. The results reveal large heterogeneity in mass loss and surface flow over the glacier surfaces, which are primarily caused by the presence of surface features such as ice cliffs and supra-glacial lakes. Accordingly, we systematically analyze those features using an object-based approach and relate their characteristics to the observed dynamics. We show that ice cliffs and supra-glacial lakes are contributing to a significant portion of the melt water of debris covered glaciers and we conclude that UAVs have great potential in understanding the key surface processes that remain largely undetected by using satellite remote sensing.

  9. Temporal dynamics of motivation-cognitive control interactions revealed by high-resolution pupillometry

    Directory of Open Access Journals (Sweden)

    Kimberly Sarah Chiew

    2013-01-01

    Full Text Available Motivational manipulations, such as the presence of performance-contingent reward incentives, can have substantial influences on cognitive control. Previous evidence suggests that reward incentives may enhance cognitive performance specifically through increased preparatory, or proactive, control processes. The present study examined reward influences on cognitive control dynamics in the AX-Continuous Performance Task (AX-CPT, using high-resolution pupillometry. In the AX-CPT, contextual cues must be actively maintained over a delay in order to appropriately respond to ambiguous target probes. A key feature of the task is that it permits dissociable characterization of preparatory, proactive control processes (i.e., utilization of context and reactive control processes (i.e., target-evoked interference resolution. Task performance profiles suggested that reward incentives enhanced proactive control (context utilization. Critically, pupil dilation was also increased on reward incentive trials during context maintenance periods, suggesting trial-specific shifts in proactive control, particularly when context cues indicated the need to overcome the dominant target response bias. Reward incentives had both transient (i.e., trial-by-trial and sustained (i.e., block-based effects on pupil dilation, which may reflect distinct underlying processes. The transient pupillary effects were present even when comparing against trials matched in task performance, suggesting a unique motivational influence of reward incentives. These results suggest that pupillometry may be a useful technique for investigating reward motivational signals and their dynamic influence on cognitive control.

  10. Temporal dynamics of motivation-cognitive control interactions revealed by high-resolution pupillometry.

    Science.gov (United States)

    Chiew, Kimberly S; Braver, Todd S

    2013-01-01

    Motivational manipulations, such as the presence of performance-contingent reward incentives, can have substantial influences on cognitive control. Previous evidence suggests that reward incentives may enhance cognitive performance specifically through increased preparatory, or proactive, control processes. The present study examined reward influences on cognitive control dynamics in the AX-Continuous Performance Task (AX-CPT), using high-resolution pupillometry. In the AX-CPT, contextual cues must be actively maintained over a delay in order to appropriately respond to ambiguous target probes. A key feature of the task is that it permits dissociable characterization of preparatory, proactive control processes (i.e., utilization of context) and reactive control processes (i.e., target-evoked interference resolution). Task performance profiles suggested that reward incentives enhanced proactive control (context utilization). Critically, pupil dilation was also increased on reward incentive trials during context maintenance periods, suggesting trial-specific shifts in proactive control, particularly when context cues indicated the need to overcome the dominant target response bias. Reward incentives had both transient (i.e., trial-by-trial) and sustained (i.e., block-based) effects on pupil dilation, which may reflect distinct underlying processes. The transient pupillary effects were present even when comparing against trials matched in task performance, suggesting a unique motivational influence of reward incentives. These results suggest that pupillometry may be a useful technique for investigating reward motivational signals and their dynamic influence on cognitive control.

  11. Chondroblastoma of the temporal bone

    Energy Technology Data Exchange (ETDEWEB)

    Kobayashi, Yuko; Murakami, Ryusuke; Toba, Masahiro; Ichikawa, Taro [Dept. of Radiology, Nippon Medical School, Tokyo (Japan); Kanazawa, Ryuzaburo; Sanno, Naoko; Shimura, Toshiro [Dept. of Neurosurgery, Nippon Medical School, Tokyo (Japan); Sawada, Namie; Hosone, Masaru [Dept. of Pathology, Nippon Medical School, Tokyo (Japan); Kumazaki, Tatsuo [Dept. of Radiology, Nippon Medical School, Tokyo (Japan)

    2001-12-01

    A rare case of chondroblastoma arising from the temporal bone that occurred in a 60-year-old woman is reported. The tumor appeared well demarcated and osteolytic on the radiographs. CT scan clearly depicted marginal and central calcification in the tumor. MR imaging demonstrated two components in the tumor: a solid component with predominantly low signal intensities on both T1- and T2-weighted sequences, and a multilocular cystic component with T1- and T2-elongation and fluid-fluid levels on the T2-weighted images. Postcontrast MR imaging revealed marked enhancement in the solid component and the septa of the cystic component. (orig.)

  12. Using high resolution satellite multi-temporal interferometry for landslide hazard detection in tropical environments: the case of Haiti

    Science.gov (United States)

    Wasowski, Janusz; Nutricato, Raffaele; Nitti, Davide Oscar; Bovenga, Fabio; Chiaradia, Maria Teresa; Piard, Boby Emmanuel; Mondesir, Philemon

    2015-04-01

    Synthetic aperture radar (SAR) multi-temporal interferometry (MTI) is one of the most promising satellite-based remote sensing techniques for fostering new opportunities in landslide hazard detection and assessment. MTI is attractive because it can provide very precise quantitative information on slow slope displacements of the ground surface over huge areas with limited vegetation cover. Although MTI is a mature technique, we are only beginning to realize the benefits of the high-resolution imagery that is currently acquired by the new generation radar satellites (e.g., COSMO-SkyMed, TerraSAR-X). In this work we demonstrate the potential of high resolution X-band MTI for wide-area detection of slope instability hazards even in tropical environments that are typically very harsh (eg. coherence loss) for differential interferometry applications. This is done by presenting an example from the island of Haiti, a tropical region characterized by dense and rapidly growing vegetation, as well as by significant climatic variability (two rainy seasons) with intense precipitation events. Despite the unfavorable setting, MTI processing of nearly 100 COSMO-SkyMed (CSK) mages (2011-2013) resulted in the identification of numerous radar targets even in some rural (inhabited) areas thanks to the high resolution (3 m) of CSK radar imagery, the adoption of a patch wise processing SPINUA approach and the presence of many man-made structures dispersed in heavily vegetated terrain. In particular, the density of the targets resulted suitable for the detection of some deep-seated and shallower landslides, as well as localized, very slow slope deformations. The interpretation and widespread exploitation of high resolution MTI data was facilitated by Google EarthTM tools with the associated high resolution optical imagery. Furthermore, our reconnaissance in situ checks confirmed that MTI results provided useful information on landslides and marginally stable slopes that can represent a

  13. 3D high resolution tracking of ice flow using mutli-temporal stereo satellite imagery, Franz Josef Glacier, New Zealand

    Science.gov (United States)

    Leprince, S.; Lin, J.; Ayoub, F.; Herman, F.; Avouac, J.

    2013-12-01

    We present the latest capabilities added to the Co-Registration of Optically Sensed Images and Correlation (COSI-Corr) software, which aim at analyzing time-series of stereoscopic imagery to document 3D variations of the ground surface. We review the processing chain and present the new and improved modules for satellite pushbroom imagery, in particular the N-image bundle block adjustment to jointly optimize the viewing geometry of multiple acquisitions, the improved multi-scale image matching based on Semi-Global Matching (SGM) to extract high resolution topography, and the triangulation of multi-temporal disparity maps to derive 3D ground motion. In particular, processes are optimized to run on a cluster computing environment. This new suite of algorithms is applied to the study of Worldview stereo imagery above the Franz Josef, Fox, and Tasman Glaciers, New Zealand, acquired on 01/30/2013, 02/09/2013, and 02/28/2013. We derive high resolution (1m post-spacing) maps of ice flow in three dimensions, where ice velocities of up to 4 m/day are recorded. Images were collected in early summer during a dry and sunny period, which followed two weeks of unsettled weather with several heavy rainfall events across the Southern Alps. The 3D tracking of ice flow highlights the surface response of the glaciers to changes in effective pressure at the ice-bedrock interface due to heavy rainfall, at an unprecedented spatial resolution.

  14. High-resolution (spatial and temporal) Hydrodynamic Modeling in the Lower Mississippi River Delta

    Science.gov (United States)

    Karadogan, E.; Danchuk, S.; Berger, C.; Brown, G.; Willson, C.

    2007-12-01

    The lower Mississippi River is a highly engineered system existing in one of the world's largest deltas. This system is subject to a variety of spatial and temporal forcings due to its large watershed (drains about 41% of the continental U.S.) and from the Gulf of Mexico. Future perturbations on this system are anticipated due to the impacts of global climate change (e.g., rising eustatic sea level, changes in weather patterns) and from proposed modifications to the system such as diversion structures aimed at providing freshwater nutrients and sediments to the rapidly degrading coastal wetlands. Numerical modeling will play a large role in improving our understanding and management of the system and the ability to properly design future structural features. These models will need to have the necessary spatial and temporal resolution to account for the many important processes in the river, the Gulf of Mexico, and in the wetland areas where small distributary channels will form and wetting/drying must be accounted for. This paper will investigate the ability of a 2D shallow water and sediment model to reproduce the complex distributary development associated with flow diversions into quiescent bays. A reach of the Lower Mississippi River from Point a la Hache to the Gulf of Mexico was used as a test domain to evaluate the performance and capabilities of the U.S. Army Corps of Engineers ADaptive Hydraulics (ADH) model. ADH is an unstructured finite element modeling system that includes unsaturated Richards' equations for groundwater, Navier Stokes for nonhydrostatic flow calculations, and Shallow Water equations. ADH conducts automated refinement and coarsening of the mesh based upon flow characteristics. In this case the 2D shallow water model is being used. It includes coupled flow and sedimentation. An unstructured mesh was developed for the study area which includes detailed bathymetry and topography from available survey data. The mesh is fine enough to capture

  15. Sentiment in New York City: A High Resolution Spatial and Temporal View

    CERN Document Server

    Bertrand, Karla Z; Virdee, Kawandeep; Gros, Andreas; Bar-Yam, Yaneer

    2013-01-01

    Measuring public sentiment is a key task for researchers and policymakers alike. The explosion of available social media data allows for a more time-sensitive and geographically specific analysis than ever before. In this paper we analyze data from the micro-blogging site Twitter and generate a sentiment map of New York City. We develop a classifier specifically tuned for 140-character Twitter messages, or tweets, using key words, phrases and emoticons to determine the mood of each tweet. This method, combined with geotagging provided by users, enables us to gauge public sentiment on extremely fine-grained spatial and temporal scales. We find that public mood is generally highest in public parks and lowest at transportation hubs, and locate other areas of strong sentiment such as cemeteries, medical centers, a jail, and a sewage facility. Sentiment progressively improves with proximity to Times Square. Periodic patterns of sentiment fluctuate on both a daily and a weekly scale: more positive tweets are posted...

  16. Changes in bone macro- and microstructure in diabetic obese mice revealed by high resolution microfocus X-ray computed tomography

    Science.gov (United States)

    Kerckhofs, G.; Durand, M.; Vangoitsenhoven, R.; Marin, C.; van der Schueren, B.; Carmeliet, G.; Luyten, F. P.; Geris, L.; Vandamme, K.

    2016-10-01

    High resolution microfocus X-ray computed tomography (HR-microCT) was employed to characterize the structural alterations of the cortical and trabecular bone in a mouse model of obesity-driven type 2 diabetes (T2DM). C57Bl/6J mice were randomly assigned for 14 weeks to either a control diet-fed (CTRL) or a high fat diet (HFD)-fed group developing obesity, hyperglycaemia and insulin resistance. The HFD group showed an increased trabecular thickness and a decreased trabecular number compared to CTRL animals. Midshaft tibia intracortical porosity was assessed at two spatial image resolutions. At 2 μm scale, no change was observed in the intracortical structure. At 1 μm scale, a decrease in the cortical vascular porosity of the HFD bone was evidenced. The study of a group of 8 week old animals corresponding to animals at the start of the diet challenge revealed that the decreased vascular porosity was T2DM-dependant and not related to the ageing process. Our results offer an unprecedented ultra-characterization of the T2DM compromised skeletal micro-architecture and highlight an unrevealed T2DM-related decrease in the cortical vascular porosity, potentially affecting the bone health and fragility. Additionally, it provides some insights into the technical challenge facing the assessment of the rodent bone structure using HR-microCT imaging.

  17. Schneiderian papilloma of the temporal bone

    NARCIS (Netherlands)

    van der Putten, L.; Bloemena, E.; Merkus, P.; Hensen, E.F.

    2013-01-01

    Temporal bone Schneiderian papilloma may present as a primary tumour originating from the middle ear and mastoid process, or an extension from sinonasal disease. Both forms are rare, this being only the 18th case of primary temporal bone Schneiderian papilloma described to date. Although the current

  18. Bilateral Asymmetry of Radius and Tibia Bone Macroarchitecture and Microarchitecture: A High-Resolution Peripheral Quantitative Computed Tomography Study.

    Science.gov (United States)

    Hildebrandt, Erin M; Manske, Sarah L; Hanley, David A; Boyd, Steven K

    2016-01-01

    Studies assessing bone health often select the dominant or nondominant limb to scan, but not both, for efficiency reasons. New scanning technology allows 3-dimensional (3D) visualization of the microarchitecture in bone, but it is not well understood whether there are differences between the dominant and nondominant limbs. Using 3D high-resolution peripheral quantitative computed tomography (HR-pQCT), the aim of this study is to investigate the effect of limb dominance on bone macroarchitecture and microarchitecture. Healthy male and female participants (N=100; 59 female, 41 male), mean age 30.7±12.1 years, were scanned at both radii and tibiae using HR-pQCT. Hand and foot dominance were determined by the participant's self-report. Most participants were right hand dominant (94.0%) and right foot dominant (91.0%). In the pooled cohort, the dominant radius had significantly greater cortical area (2.11%; p=0.002) and failure load (3.00%; p=0.001). At the tibia, the dominant foot had significantly lower bone mineral density (-0.77%; p=0.042), cortical area (-1.05%; p=0.031), and thickness (-1.51%; p=0.017). For females, there were no differences at the radius, but at the tibia, the dominant side had greater cross-sectional area (1.03%; p=0.044). Our data suggest that dominance has a small yet significant effect on macroarchitecture at both the ultradistal radius and tibia but not microarchitecture. This work emphasizes that it is important to be consistent in the selection of either dominant or nondominant limbs for HR-pQCT cohort studies; however, in the case where the opposite limb needs to be scanned, there would be small differences in macroarchitecture and no significant differences in microarchitecture anticipated.

  19. Semi-automatic verification of cropland and grassland using very high resolution mono-temporal satellite images

    Science.gov (United States)

    Helmholz, Petra; Rottensteiner, Franz; Heipke, Christian

    2014-11-01

    Many public and private decisions rely on geospatial information stored in a GIS database. For good decision making this information has to be complete, consistent, accurate and up-to-date. In this paper we introduce a new approach for the semi-automatic verification of a specific part of the, possibly outdated GIS database, namely cropland and grassland objects, using mono-temporal very high resolution (VHR) multispectral satellite images. The approach consists of two steps: first, a supervised pixel-based classification based on a Markov Random Field is employed to extract image regions which contain agricultural areas (without distinction between cropland and grassland), and these regions are intersected with boundaries of the agricultural objects from the GIS database. Subsequently, GIS objects labelled as cropland or grassland in the database and showing agricultural areas in the image are subdivided into different homogeneous regions by means of image segmentation, followed by a classification of these segments into either cropland or grassland using a Support Vector Machine. The classification result of all segments belonging to one GIS object are finally merged and compared with the GIS database label. The developed approach was tested on a number of images. The evaluation shows that errors in the GIS database can be significantly reduced while also speeding up the whole verification task when compared to a manual process.

  20. Landuse change detection in a surface coal mine area using multi-temporal high resolution satellite images

    Energy Technology Data Exchange (ETDEWEB)

    Demirel, N.; Duzgun, S.; Kemal Emil, M. [Middle East Technical Univ., Ankara (Turkey). Dept. of Mining Engineering

    2010-07-01

    Changes in the landcover and landuse of a mine area can be caused by surface mining activities, exploitation of ore and stripping and dumping overburden. In order to identify the long-term impacts of mining on the environment and land cover, these changes must be continuously monitored. A facility to regularly observe the progress of surface mining and reclamation is important for effective enforcement of mining and environmental regulations. Remote sensing provides a powerful tool to obtain rigorous data and reduce the need for time-consuming and expensive field measurements. The purpose of this study was to conduct post classification change detection for identifying, quantifying, and analyzing the spatial response of landscape due to surface lignite coal mining activities in Goynuk, Bolu, Turkey, from 2004 to 2008. The paper presented the research algorithm which involved acquiring multi temporal high resolution satellite data; preprocessing the data; performing image classification using maximum likelihood classification algorithm and performing accuracy assessment on the classification results; performing post classification change detection algorithm; and analyzing the results. Specifically, the paper discussed the study area, data and methodology, and image preprocessing using radiometric correction. Image classification and change detection were also discussed. It was concluded that the mine and dump area decreased by 192.5 ha from 2004 to 2008 and was caused by the diminishing reserves in the area and decline in the required production. 5 refs., 2 tabs., 4 figs.

  1. Bi-Temporal Analysis of High-Resolution Satellite Imagery in Support of a Forest Conservation Program in Western Uganda

    Science.gov (United States)

    Thomas, N.; Lambin, E.; Audy, R.; Biryahwaho, B.; de Laat, J.; Jayachandran, S.

    2014-12-01

    Recent studies in land use sustainability have shown the conservation value of even small forest fragments in tropical smallholder agricultural regions. Forest patches provide important ecosystem services, wildlife habitat, and support human livelihoods. Our study incorporates multiple dates of high-resolution Quickbird imagery to map forest disturbance and regrowth in a smallholder agricultural landscape in western Uganda. This work is in support of a payments for ecosystem services (PES) project which uses a randomized controlled trial to assess the efficacy of PES for enhancing forest conservation. The research presented here details the remote sensing phase of this project. We developed an object-based methodology for detecting forest change from high-resolution imagery that calculates per class image reflectance and change statistics to determine persistent forest, non-forest, forest gain, and forest loss classes. The large study area (~ 2,400 km2) necessitated using a combination of 10 different image pairs of varying seasonality, sun angle, and viewing angle. We discuss the impact of these factors on mapping results. Reflectance data was used in conjunction with texture measures and knowledge-driven modeling to derive forest change maps. First, baseline Quickbird images were mapped into tree cover and non-tree categories based on segmented image objects and field inventory data, applied through a classification and regression tree (CART) classifier. Then a bi-temporal segmentation layer was generated and a series of object metrics from both image dates were extracted. A sample set of persistent forest objects that remained undisturbed was derived from the tree cover map and the red band (B3) change values. We calculated a variety of statistical indices for these persistent tree cover objects from the post- survey imagery to create maps of both forest cover loss and forest cover gain. These results are compared to visually assessed image objects in addition

  2. Schneiderian papilloma of the temporal bone.

    Science.gov (United States)

    van der Putten, Lisa; Bloemena, Elisabeth; Merkus, Paul; Hensen, Erik F

    2013-12-05

    Temporal bone Schneiderian papilloma may present as a primary tumour originating from the middle ear and mastoid process, or an extension from sinonasal disease. Both forms are rare, this being only the 18th case of primary temporal bone Schneiderian papilloma described to date. Although the current patient has remained disease free after excision of the papilloma, the reported recurrence rate is high, comparable to sinonasal Schneiderian papilloma with extrasinus extension. Malignant progression of primary Schneiderian papillomas is significantly reduced as compared to Schneiderian papillomas that extend from the sinonasal tract into the temporal bone. A positive human papilloma virus status, as found in this case, is a common feature and prognostic factor of sinonasal Schneiderian papilloma but an infrequent finding in temporal bone disease. Owing to the high recurrence rate, the risk of malignant progression and the absence of reliable prognostic markers, stringent follow-up consisting of otoscopy, nasendoscopy and imaging is essential.

  3. Agro-hydrology and multi-temporal high-resolution remote sensing: toward an explicit spatial processes calibration

    Science.gov (United States)

    Ferrant, S.; Gascoin, S.; Veloso, A.; Salmon-Monviola, J.; Claverie, M.; Rivalland, V.; Dedieu, G.; Demarez, V.; Ceschia, E.; Probst, J.-L.; Durand, P.; Bustillo, V.

    2014-12-01

    The growing availability of high-resolution satellite image series offers new opportunities in agro-hydrological research and modeling. We investigated the possibilities offered for improving crop-growth dynamic simulation with the distributed agro-hydrological model: topography-based nitrogen transfer and transformation (TNT2). We used a leaf area index (LAI) map series derived from 105 Formosat-2 (F2) images covering the period 2006-2010. The TNT2 model (Beaujouan et al., 2002), calibrated against discharge and in-stream nitrate fluxes for the period 1985-2001, was tested on the 2005-2010 data set (climate, land use, agricultural practices, and discharge and nitrate fluxes at the outlet). Data from the first year (2005) were used to initialize the hydrological model. A priori agricultural practices obtained from an extensive field survey, such as seeding date, crop cultivar, and amount of fertilizer, were used as input variables. Continuous values of LAI as a function of cumulative daily temperature were obtained at the crop-field level by fitting a double logistic equation against discrete satellite-derived LAI. Model predictions of LAI dynamics using the a priori input parameters displayed temporal shifts from those observed LAI profiles that are irregularly distributed in space (between field crops) and time (between years). By resetting the seeding date at the crop-field level, we have developed an optimization method designed to efficiently minimize this temporal shift and better fit the crop growth against both the spatial observations and crop production. This optimization of simulated LAI has a negligible impact on water budgets at the catchment scale (1 mm yr-1 on average) but a noticeable impact on in-stream nitrogen fluxes (around 12%), which is of interest when considering nitrate stream contamination issues and the objectives of TNT2 modeling. This study demonstrates the potential contribution of the forthcoming high spatial and temporal resolution

  4. Pulmonary fungal infections after bone marrow transplantation: the value of high-resolution computed tomography in predicting their etiology

    Institute of Scientific and Technical Information of China (English)

    LI Xiang-sheng; ZHU Hong-xian; FAN Hong-xia; ZHU Ling; WANG Heng-xiang; SONG Yun-long

    2011-01-01

    Background The correct diagnosis of etiology of fungal infection after bone marrow transplantation is very important to the choice of antifungal drugs and a premise for improvement of therapeutic efficacy.This study aimed to compare high-resolution computed tomography (HRCT) findings of the pulmonary fungal infections to determine whether the etiology of various fungal infections could be diagnosed with HRCT.Methods Eighty-five cases were enrolled.According to the pathogens responsible for fungal infections,the patients were classified into three groups including invasive aspergillosis (n=52),candidiasis (n=19) and cryptococcosis (n=14)groups.All the patients underwent HRCT scans.Two independent radiologists retrospectively analyzed the HRCT scans regarding CT patterns and distribution of lung abnormality.Results Most fungal infections in the three groups occurred in the neutropenic phase.There was no significant difference in the constituent ratio of fungal infections at different phases after bone marrow transplantation among the three groups.Agreement between the two observers for all the CT characteristics of fungal infections was excellent (k>0.75).There was a significant difference in occurrence ratio of mass among the three groups (P=0.02).Occurrence ratio of mass (43.3%,13/30) in the group with invasive aspergillosis was higher than in each of other two groups (20.0%,2/10;14.3%,1/7).There was no significant difference in other CT characteristics of nodules or masses; including number,margin,halo sign,cavitation and air-crescent sign.There was no significant difference in number,margin,air bronchogram and distribution of air-space consolidation.Conclusions The HRCT appearance of various pulmonary fungal infections has a great deal of overlap and is nonspecific.Mass is more common in invasive aspergillosis,which is helpful to the diagnosis of invasive aspergillosis after bone marrow transplantation.

  5. Imaging innovations in temporal bone disorders.

    Science.gov (United States)

    Corrales, C Eduardo; Fischbein, Nancy; Jackler, Robert K

    2015-04-01

    The development of new imaging techniques coupled with new treatment algorithms has created new possibilities in treating temporal bone diseases. This article provides an overview of recent imaging innovations that can be applied to temporal bone diseases. Topics covered include the role of magnetic resonance (MR) diffusion-weighted imaging in cholesteatomas and skull base epidermoids, whole-body molecular imaging in paragangliomas of the jugular foramen, and MR arterial spin labeling perfusion for dural arteriovenous fistulas and arteriovenous malformations.

  6. Standardization of experimental animals temporal bone sections

    Institute of Scientific and Technical Information of China (English)

    Dalian Ding; Jintao Yu; Peng Li; Kelei Gao; Haiyan Jiang; Wenjuan Zhang; Hong Sun; Shankai Yin; Richard Salvi

    2015-01-01

    Preparation of the temporal bone for light microscopy is an important step in histological studies of the inner ear. Due to the complexity of structures of the inner ear, it is difficult to measure or compare structures of interest without a commonly accepted standardized measure of temporal bone sections. Therefore, standardization of temporal bone sections is very important for histological assessment of sensory hair cells and peripheral ganglion neurons in the cochlear and vestibular systems. The standardized temporal bone sectioning is oriented to a plane parallel to the outer and internal auditory canals. Sections are collected from the epitympanum to the hypotympanum to reveal layers in the order of the crista ampullaris of the superior and lateral semicircular canals, macula utriculi and macula sacculi, superior vestibular ganglion neurons, macula of saccule and inferior vestibular ganglion neurons, cochlear modiolus, endolymphatic duct and endolymphatic sac, and finally the crista ampullaris of the posterior semicircular canal. Moreover, technical details of preparing for temporal bone sectioning including fixation, decalcification, whole temporal bone staining, embedding penetration, and embedding orientation are also discussed.

  7. Giant osteoblastoma of temporal bone: case report

    Directory of Open Access Journals (Sweden)

    FIGUEIREDO EBERVAL GADELHA

    1998-01-01

    Full Text Available Benign osteoblastoma is an uncommon bone tumor accounting for approximately 1% of all bone tumors. There are only 35 cases of skull osteoblastoma reported in the literature. We describe the case of a 23 year old male with a giant osteoblastoma of temporal bone submitted to a total removal of the tumor after an effective embolization of all external carotid branches. The authors discuss diagnostic and management aspects of this uncommon skull tumor.

  8. A high-resolution temporal record of environmental changes in the Eastern Caribbean (Guadeloupe) from 40 to 10 ka BP

    Science.gov (United States)

    Royer, Aurélien; Malaizé, Bruno; Lécuyer, Christophe; Queffelec, Alain; Charlier, Karine; Caley, Thibaut; Lenoble, Arnaud

    2017-01-01

    In neotropical regions, fossil bat guano accumulated over time as laminated layers in caves, hence providing a high-resolution temporal record of terrestrial environmental changes. Additionally, cave settings have the property to preserve such organic sediments from processes triggered by winds (deflation, abrasion and sandblasting) and intense rainfall (leaching away). This study reports both stable carbon and nitrogen isotope compositions of frugivorous bat guano deposited in a well-preserved stratigraphic succession of Blanchard Cave on Marie-Galante, Guadeloupe. These isotopic data are discussed with regard to climate changes and its specific impact on Eastern Caribbean vegetation during the Late Pleistocene from 40 to 10 ka cal. BP. Guano δ13C values are higher than modern ones, suggesting noticeable vegetation changes. This provides also evidence for overall drier environmental conditions during the Pleistocene compared to today. Meanwhile, within this generally drier climate, shifts between wetter and drier conditions can be observed. Large temporal amplitudes in both δ13C and δ15N variations reaching up to 5.9‰ and 16.8‰, respectively, also indicate these oceanic tropical environments have been highly sensitive to regional or global climatic forcing. Stable isotope compositions of bat guano deposited from 40 to 35 ka BP, the Last Glacial Maximum and the Younger-Dryas reveal relatively wet environmental conditions whereas, at least from the end of the Heinrich event 1 and the Bølling period the region experienced drier environmental conditions. Nevertheless, when considering uncertainties in the model age, the isotopic record of Blanchard Cave show relatively similar variations with known proxy records from the northern South America and Central America, suggesting thus that the Blanchard Cave record is a robust proxy of past ITCZ migration. Teleconnections through global atmospheric pattern suggest that islands of the eastern Caribbean Basin could

  9. Parathyroidectomy improves bone geometry and microarchitecture in female patients with primary hyperparathyroidism. A 1-year prospective controlled study using high resolution peripheral quantitative computed tomography

    DEFF Research Database (Denmark)

    Hansen, Stinus; Hauge, Ellen M; Rasmussen, Lars

    2012-01-01

    controlled study, high-resolution peripheral quantitative computed tomography (HR-pQCT) was used to evaluate changes in bone geometry, volumetric BMD (vBMD), microarchitecture, and estimated strength in female patients with PHPT before and 1 year after PTX, compared to healthy controls. Twenty-seven women...

  10. Pneumolabyrinth secondary to temporal bone fracture: a case report and review of the literature

    Directory of Open Access Journals (Sweden)

    Bacciu A

    2014-09-01

    Full Text Available Andrea Bacciu,1 Vincenzo Vincenti,1 Sampath Chandra Prasad,1 Daniela Tonni,1 Elisa Ventura,2 Salvatore Bacciu,1 Enrico Pasanisi1 1Department of Clinical and Experimental Medicine, Unit of Audiology and Paediatric Otolaryngology, 2Department of Neuroradiology, University Hospital of Parma, Parma, Italy Abstract: Pneumolabyrinth following temporal bone fracture is an extremely rare condition. It results from air entering the inner ear when a communication between the air-filled middle ear spaces and inner ear is established. The imaging modality of choice for pneumolabyrinth is high-resolution computed tomography of the temporal bone. Treatment options include conservative management (bed rest, antibiotics, corticosteroids or surgery (exploratory tympanotomy. We present the case of a 31-year-old female who had pneumolabyrinth secondary to a temporal bone fracture. The patient was treated surgically and made a full clinical recovery. Keywords: pneumolabyrinth, temporal bone fractures, head trauma

  11. Unsaturation level decreased in bone marrow fat of postmenopausal women with low bone density using high resolution magic angle spinning (HRMAS) (1)H NMR spectroscopy.

    Science.gov (United States)

    Li, Xiaojuan; Shet, Keerthi; Xu, Kaipin; Rodríguez, Juan Pablo; Pino, Ana María; Kurhanewicz, John; Schwartz, Ann; Rosen, Clifford J

    2017-08-18

    There are increasing evidences suggesting bone marrow adiposity tissue (MAT) plays a critical role in affecting both bone quantity and quality. However, very limited studies that have investigated the association between the composition of MAT and bone mineral density (BMD). The goal of this study was to quantify MAT unsaturation profile of marrow samples from post-menopausal women using ex vivo high-resolution magic angle spinning (HRMAS) proton nuclear magnetic resonance ((1)H NMR) spectroscopy, and to investigate the relationship between MAT composition and BMD. Bone marrow samples were obtained by iliac crest aspiration during surgical procedures from 24 postmenopausal women (65-89years) who had hip surgery due to bone fracture or arthroplasty. Marrow fat composition parameters, in particular, unsaturation level (UL), mono-unsaturation level (MUL) and saturation level (SL), were quantified using HRMAS (1)H NMR spectroscopy. The patients were classified into three groups based on the DXA BMD T-scores: controls, osteopenia and osteoporosis. Marrow fat composition was compared between these three groups as well as between subjects with and without factures using ANOCOVA, adjusted for age. Subjects with lower BMD (n=17) had significantly lower MUL (P=0.003) and UL (P=0.039), and significantly higher SL (P=0.039) compared to controls (n=7). When separating lower BMD into osteopenia (n=9) and osteoporosis (n=8) groups, subjects with osteopenia had significantly lower MUL (P=0.002) and UL (P=0.010), and significantly higher SL (P=0.010) compared to healthy controls. No significant difference was observed between subjects with osteopenia and osteoporosis. Using HRMAS (1)H NMR, significantly lower unsaturation and significantly higher saturation levels were observed in the marrow fat of subjects with lower BMD. HRMAS (1)H NMR was shown to be a powerful tool for identifying novel MR markers of marrow fat composition that are associated with bone quality and potentially

  12. High Resolution Spatio Temporal Moments Analysis of Solute Migration Captured using Pre-clinical Medical Imaging Techniques

    Science.gov (United States)

    Dogan, M.; Moysey, S. M.; Powell, B. A.; DeVol, T. A.

    2016-12-01

    Advances in medical imaging technologies are continuously expanding the range of applications enabled within the earth sciences. While computed x-ray tomography (CT) scans have traditionally been used for investigating the structure of geologic materials, it is now possible to perform 3D time-lapse imaging of dynamic processes, such as monitoring the infiltration of water into a soil, with sub-millimeter resolution. Likewise, single photon emission computed tomography (SPECT) can provide information on the evolution of solute transport with spatial resolution on the order of a millimeter by tracking the migration of gamma-ray emitting isotopes like 99mTc and 111In. While these imaging techniques are revolutionizing our ability to look within porous media, techniques for the analysis of such rich and large data sets are limited. The spatial and temporal moments of a plume have long been used to provide quantitative measures to describe plume movement in a wide range of settings from the lab to field. Moment analysis can also be used to estimate the hydrologic properties of the porous media. In this research, we investigate the use of moments for analyzing a high resolution 4D SPECT data set collected during a 99mTc transport experiment performed in a heterogeneous column. The 4D nature of the data set makes it amenable to the use of data mining and pattern recognition methods, such as cluster analysis, to identify regions or zones within the data that exhibit abnormal or unexpected behaviors. We then compare anomalous features within the SPECT data to similar features identified within the CT image to relate the flow behavior to pore-scale structures, such as porosity differences and macropores. Such comparisons help to identify whether these features are good predictors of preferential transport. Likewise, we evaluate whether local analysis of moments can be used to infer apparent parameters governing non-conservative transport in a heterogeneous porous media, such

  13. Temporal Variations in the Roughness of Eroding River Banks Revealed by High-Resolution Digital Photogrammetry and Terrestrial Laser Scanning

    Science.gov (United States)

    Darby, S. E.; Leyland, J.; Rinaldi, M.; Teruggi, L.; Ostuni, D.

    2010-12-01

    of the roughness is approximated as a series of user defined Gaussian functions, with the skin drag component characterised by the deviation of points from the fitted curves. In our study these bank ‘roughness profiles’ are extracted from an annual series (2003-present) of high-resolution DEMs of the river bank, the latter being constructed either through digital photogrammetry or terrestrial laser scanning surveys. The DEMs are used to quantify accurately the spatial trends and amounts of annual bank erosion observed in relation to the hydrological regime of the river, and are compared to the temporal variations in river bank form and skin roughness components as the bank erodes. The data are used to evaluate the extent to which there is a dynamic feedback between the bank erosion process and bank form roughness.

  14. Stereo morphology of temporal bone and ear

    Institute of Scientific and Technical Information of China (English)

    戴朴; 刘阳; 姜泗长; 方耀云; 王今; 杨伟炎

    2004-01-01

    Background The temporal bone has the most complicated anatomic feature among the whole human body, which always challenges otolaryngologists. This study was to study three-dimensional (3D) morphology of the temporal bone and the ear by means of a computer image processing technique, for the purpose of providing a 3D image to help in pathological, diagnostic and surgical procedures. Methods Forty sets of temporal bone celloidin serial sections with reference points were prepared and the contours of selected structures and reference points were entered into a graphics programme. The technique of computer-aided 3D reconstruction was applied to obtain 3D images and parameters of the temporal bones and the ears. Stereo views of the ossicles (n=5), the facial nerves (n=11), the posterior tympanic sinuses (n=11), the posterior ampullary nerves (n=4), the endolymphatic ducts and sacs (n=5), and the bony and membranous labyrinth (n=1) were reconstructed. Results Three-dimensional images, including the cochlea, the ossicles, the nerves, the tendons and the endolymphatic fluid system in the temporal bone, were obtained. Stereo picture pairs and 3D parameters of spatial dimensions, angle and volume for these reconstructed structures were calculated. The arrangement of the ossicles, spatial relationship of the bony and membranous labyrinth, the whole course of the facial nerves, the endolymphatic sac and posterior tympanic cavity were clearly observable. Stereo picture pairs made the spatial relationships among the above-mentioned structures much clearer. The operation of the posterior ampullary nerve transection was designed and simulated on the graphic computer based on 3D anatomic investigations. Conclusion The technique of computer-aided 3D reconstruction provides a new tool to observe the morphology of the temporal bone and thus may allow design and study of new surgical approaches.

  15. Sex- and Age-Related Differences in Bone Microarchitecture in Men Relative to Women Assessed by High-Resolution Peripheral Quantitative Computed Tomography

    Directory of Open Access Journals (Sweden)

    Shreyasee Amin

    2012-01-01

    Full Text Available The trabecular and cortical compartments of bone each contributes to bone strength. Until recently, assessment of trabecular and cortical microstructure has required a bone biopsy. Now, trabecular and cortical microstructure of peripheral bone sites can be determined noninvasively using high-resolution peripheral quantitative computed tomography (HR-pQCT. Studies that have used HR-pQCT to evaluate cohorts of both men and women have provided novel insights into the changes in bone microarchitecture that occur with age between the sexes, which may help to explain the lower fracture incidence in older men relative to women. This review will highlight observations from these studies on both the sex- and age-related differences in trabecular and cortical microstructure that may underlie the differences in bone strength, and thereby fracture risk, between men and women.

  16. Temporal bone fracture and its complications

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    Objective: To explore the characteristics and treatment oftemporal bone fractures and injuries in the medial-inner ear.Methods: The clinical data of 48 cases of temporal bone fractures admitted to our hospital from January 1989 to November 1999 were retrospectively analyzed.Results: Forty-eight patients with temporal bone fractures accounted for 17.00% of the homochronous craniofacial fractures. Of the 48 cases, temporal bone fractures induced by traffic accidents accounted for 66.67%, capillary fractures for 93.75%, medial-inner ear injuries or craniocerebral injuries for 77.08% and hearing loss or tinnitus for 48.00%. The cerebrospinal fluid (CSF) otorrhea and facioplegia accounted for 36.70% and 3.00%, respectively, in the longitudinal fractures, while they were 25.00% and 37.50%, respectively, in the transversal fractures. Primary emergent operations were performed on 46 cases and neurosurgery accounted for 46.00%. Secondary procedures accounted for 16.70%. As a result, 43 cases survived (89.58%) and 5 died (10.41%).Conclusions: Traffic injury is the first high-dangerous factor for temporal bone fractures, which are often complicated with medial-inner ear or craniocerebral injury. The CSF otorrhea is common in the longitudinal fractures and facioplegia is common in the transversal fractures. The key step is to rescue the life, keep the airway unobstructed and maintain the circulation in the primary emergency treatment.

  17. Characteristic anatomical structures of rat temporal bone

    Institute of Scientific and Technical Information of China (English)

    Peng Li; Kelei Gao; Dalian Ding; Richard Salvi

    2015-01-01

    As most gene sequences and functional structures of internal organs in rats have been well studied, rat models are widely used in experi-mental medical studies. A large number of descriptions and atlas of the rat temporal bone have been published, but some detailed anatomy of its surface and inside structures remains to be studied. By focusing on some unique characteristics of the rat temporal bone, the current paper aims to provide more accurate and detailed information on rat temporal bone anatomy in an attempt to complete missing or unclear areas in the existed knowledge. We also hope this paper can lay a solid foundation for experimental rat temporal bone surgeries, and promote information exchange among colleagues, as well as providing useful guidance for novice researchers in the field of hearing research involving rats. Copyright © 2015 The Authors. Production & hosting by Elsevier (Singapore) Pte Ltd On behalf of PLA General Hospital Department of Otolaryngology Head and Neck Surgery. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/).

  18. Application of the Minkowski functionals in 3D to high-resolution MR images of trabecular bone: prediction of the biomechanical strength by nonlinear topological measures

    Science.gov (United States)

    Boehm, Holger F.; Link, Thomas M.; Monetti, Roberto A.; Mueller, Dirk; Rummeny, Ernst J.; Newitt, David; Majumdar, Sharmila; Raeth, Christoph W.

    2004-05-01

    Multi-dimensional convex objects can be characterized with respect to shape, structure, and the connectivity of their components using a set of morphological descriptors known as the Minkowski functionals. In a 3D Euclidian space, these correspond to volume, surface area, mean integral curvature, and the Euler-Poincaré characteristic. We introduce the Minkowski functionals to medical image processing for the morphological analysis of trabecular bone tissue. In the context of osteoporosis-a metabolic disorder leading to a weakening of bone due to deterioration of micro-architecture-the structure of bone increasingly gains attention in the quantification of bone quality. The trabecular architecture of healthy cancellous bone consists of a complex 3D system of inter-connected mineralised elements whereas in osteoporosis the micro-structure is dominated by gaps and disconnections. At present, the standard parameter for diagnosis and assessment of fracture risk in osteoporosis is the bone mineral density (BMD) - a bulk measure of mineralisation irrespective of structural texture characteristics. With the development of modern imaging modalities (high resolution MRI, micro-CT) with spatial resolutions allowing to depict individual trabeculae bone micro-architecture has successfully been analysed using linear, 2- dimensional structural measures adopted from standard histo-morphometry. The preliminary results of our study demonstrate that due to the complex - i.e. the non-linear - network of trabecular bone structures non-linear measures in 3D are superior to linear ones in predicting mechanical properties of trabecular bone from structural information extracted from high resolution MR image data.

  19. [Computed tomography and magnetic resonance imaging of congenital abnormalities of the temporal bone].

    Science.gov (United States)

    Czerny, C; Gstöttner, W; Imhof, H

    2003-03-01

    Congenital abnormalities of the temporal bone are mostly accompanied by conductive or sensori-neural hearing loss. Before any therapeutic procedures are done high resolution CT (HRCT) and magnetic resonance imaging (MRI) should be performed to establish the correct diagnosis and to plan the potentially surgical intervention. HRCT best depicts osseous changes especially those of the external auditory canal and the middle ear containing the ossicles and the osseous structures of the temporal bone and the petrous bone containing the inner ear. MRI excellently shows soft tissue changes of the inner ear especially on the high resolution 3DT2-weighted sequences which give a superb contrast between the nerves and the cerebro-spinal fluid. Malformations of the external auditory canal consists of aplasia or hypoplasia and those of the middle ear range form extreme hypoplasia or aplasia to very mild deformations of the ossicles. Malformations of the inner ear also range form complete aplasia to very mild hypoplasia of the organs of the inner ear as well as malformations concerning the nerves in the internal auditory canal range from aplasia to hypoplasia. Malformations of the temporal bone can either occur isolated or in combination in which malformations of the external and middle ear may be accompanied by those of the inner ear. Furthermore, malformations of the temporal bone may also occur in otofacial, otocervical or otoskeletal syndromes. These syndromes may be accompanied by certain malformations of the temporal bone. HRCT and MRI are both excellent methods to depict congenital abnormalities of the temporal bone and of the inner ear and should be used as complementary methods because HRCT best depicts osseous changes and MRI superbly depicts soft tissue changes. Both methods are important to establish the correct diagnosis to plan the therapeutic procedures.

  20. Non-invasive predictors of human cortical bone mechanical properties: T(2-discriminated H NMR compared with high resolution X-ray.

    Directory of Open Access Journals (Sweden)

    R Adam Horch

    Full Text Available Recent advancements in magnetic resonance imaging (MRI have enabled clinical imaging of human cortical bone, providing a potentially powerful new means for assessing bone health with molecular-scale sensitivities unavailable to conventional X-ray-based diagnostics. To this end, (1H nuclear magnetic resonance (NMR and high-resolution X-ray signals from human cortical bone samples were correlated with mechanical properties of bone. Results showed that (1H NMR signals were better predictors of yield stress, peak stress, and pre-yield toughness than were the X-ray derived signals. These (1H NMR signals can, in principle, be extracted from clinical MRI, thus offering the potential for improved clinical assessment of fracture risk.

  1. Establishing a temporal bone laboratory: considerations for ENT specialist training.

    LENUS (Irish Health Repository)

    Fennessy, B G

    2012-02-01

    Cadaveric temporal bone dissection in a temporal bone laboratory is a vital component in training safe, competent otorhinolaryngologists. Recent controversies pertaining to organ retention have resulted in a more limited supply of temporal bones. Consequently, current trainees are dissecting far fewer bones than their consultants. We discuss the establishment of a temporal bone laboratory in the Department of Anatomy in the University College Cork, from the timely preparation and preservation of the tissue to its disposal. Comparisons are drawn between our experience and that of the United States training schemes. The temporal bone laboratory in Cork is the only one in existence in Ireland. The exposure and experience obtained by registrars rotating through Cork, has resulted in noticeable improvements in their operative abilities. The temporal bone laboratory remains a core component to training. It is hoped that this article may facilitate other units overcoming obstacles to establish a temporal bone laboratory.

  2. Bilateral Facial Paralysis Caused by Temporal Bone Fracture: A Case Report

    Directory of Open Access Journals (Sweden)

    Ghiasi

    2016-02-01

    Full Text Available Introduction Although bilateral facial nerve palsy is a rare condition, its etiology is more detectable than the unilateral type. A temporal bone fracture is one cause of bilateral facial nerve palsy, contributing in 3% of the cases. Case Presentation Here, we report the case of a 35-year-old man complaining of bilateral incomplete eye closure, two weeks after a closed head injury caused by a motor vehicle accident. Conclusions The high resolution computed tomography findings revealed a bilateral temporal bone fracture line, which extended to the fallopian canal. With regard to treatment, near complete recovery was obvious after two weeks of treatment with oral corticosteroids. Overall, bilateral facial palsy is hard to diagnose; therefore, clinical suspicion and the early detection of facial nerve injuries is necessary for good nerve recovery in temporal bone fractures.

  3. Primary Ameloblastoma of the Temporal Bone.

    Science.gov (United States)

    Košec, Andro; Ajduk, Jakov; Ries, Mihael; Trotić, Robert

    2017-06-01

    Ameloblastoma is a locally aggressive tumor derived from odontogenic epithelium. Although benign, its clinical behavior can often exhibit malignant characteristics. It is marked by slow and persistent growth with infiltration of adjacent tissues. Almost 70% occur in the mandible in patients older than 30 years. Recurrence of ameloblastoma from inadequate treatment is frequent. Because of its slow growth, recurrences can present decades after primary surgery. A primary ameloblastoma in an area outside the mandibular, maxillary, and infratemporal fossa regions has not been described in detail to date, with only 1 possible case mentioned in the literature. The authors present a case of primary temporal bone ameloblastoma in a 17-year-old boy. The tumor originated in the left mastoid, infiltrated the lateral semicircular canal, facial nerve, and cochlea, and adhered to the sigmoid sinus and posterior cranial fossa dura. Although invasion of multiple structures in the infratemporal fossa and temporal bone leads to variable disease presentation, this case is unique because the first symptom of disease was sudden and recurring unilateral sensorineural hearing loss. Surgery required transection of the facial nerve. Histopathology confirmed primary temporal bone ameloblastoma. The difficulties in achieving wide surgical margins, diagnostics, and further management are addressed. Copyright © 2017 American Association of Oral and Maxillofacial Surgeons. Published by Elsevier Inc. All rights reserved.

  4. CT of temporal bone - IV. inner ear

    Energy Technology Data Exchange (ETDEWEB)

    Kwon, Jae Yoon; Sung, Kyu Bo; Youn, Eun Kyoung; Park, Youn Kyeung; Lee, Young Uk [Koryo general Hospital, Seoul (Korea, Republic of)

    1990-07-15

    Temporal bone CT was done in 697 patients from April 1985 to October 1989. The abnormal findings were seen in 453 patients, which were chronic otitis media in 355 patients, fracture in 49 patients and congenital anomaly in 44 patients, etc. The abnormal findings of inner ear were observed on 46 patients. The results were summarized as follows : 1. The incidence of inner ear involvement by chronic otitis media was 7.3% (26/355 : labyrinthine fistula in 17 patients, labyrinthitis ossificans in 9 patients). Labyrinthine fistula was most commonly located on lateral semicircular canal (15/17, 88.2%). 2. Fusion of vestibule with lateral semicircular canal and formation of common cavity was demonstrated incidentally in 5 patients (0.7% of total number of temporal bone CT), and bilateral in 3 patients. 3. The incidence of inner ear anomaly in congenital ear anomaly was 11.4% (5/44). All cases were bilateral and three patients showed associated middle ear anomaly. 4. The incidence of involvement of bony labyrinth in temporal bone fracture was 10.2% (5/49). Labyrinthine fracture was seen all patients of transverse(3) and mixed fracture(1). In longitudinal fracture, labyrinthine fracture was seen in 2.2% (1/45). 5. Others were traumatic labyrinthitis ossificans(1), intracanalicular acoustic neuroma(3) and facial nerve neuroma(1)

  5. In vivo application of 3D-line skeleton graph analysis (LSGA) technique with high-resolution magnetic resonance imaging of trabecular bone structure.

    Science.gov (United States)

    Pothuaud, Laurent; Newitt, David C; Lu, Ying; MacDonald, Brian; Majumdar, Sharmila

    2004-05-01

    Over the last several years magnetic resonance (MR) imaging has emerged as a means of measuring in vivo 3D trabecular bone structure. In particular, MR based diagnosis could be used to complement standard bone mineral density (BMD) methods for assessing osteoporosis and evaluating longitudinal changes. The aim of this study was to demonstrate the feasibility of using the 3D-LSGA technique for the evaluation of trabecular bone structure of high-resolution MR images, particularly for assessing longitudinal changes, in vivo. First, the reproducibility of topological 3D-LSGA based measurements was evaluated in a set of seven volunteers, and coefficients of variations ranged from 3.5% to 6%. Second, high-resolution MR images of the radius in 30 postmenopausal women from a placebo controlled drug study (Idoxifene), divided into placebo ( n=9) and treated ( n=21) groups, were obtained at baseline (BL) and after 1 year of treatment (follow-up, FU). In addition, dual X-ray absorptiometry (DXA) measures of BMD were obtained in the distal radius. Standard morphological measurements based on the mean intercept length (MIL) technique as well as 3D-LSGA based measurements were applied to the 3D MR images. Significant changes from BL to FU were detected, in the treated group, using the topological 3D-LSGA based measurements, morphological measures of volume of connected trabeculae and App Tb.N from MIL analysis. The duration of the study was short, and the number of patients remaining in the study was small, hence these results cannot be interpreted with regard to a true therapeutic response. Furthermore, the site (wrist) and the drug (idoxifene) are not optimal for follow-up study. However, this paper demonstrated the feasibility of using 3D-LSGA based evaluation coupled with in vivo high-resolution MR imaging as a complementary approach for the monitoring of trabecular bone changes in individual subjects.

  6. Non-invasive bone competence analysis by high-resolution pQCT: an in vitro reproducibility study on structural and mechanical properties at the human radius.

    Science.gov (United States)

    Mueller, Thomas L; Stauber, Martin; Kohler, Thomas; Eckstein, Felix; Müller, Ralph; van Lenthe, G Harry

    2009-02-01

    Osteoporosis is defined as a skeletal disorder characterized by compromised bone strength. Bone strength depends, among others, on bone density, bone geometry and its internal architecture. With the recent introduction of a new generation high-resolution 3D peripheral quantitative computed tomography (HR-pQCT) system, direct quantification of structural bone parameters has become feasible. Furthermore, it has recently been demonstrated that bone mechanical competence can be derived from HR-pQCT based micro-finite element modeling (microFE). However, reproducibility data for HR-pQCT-derived mechanical indices is not well-known. Therefore, the aim of this study was to quantify reproducibility of HR-pQCT-derived indices. We measured 14 distal formalin-fixed cadaveric forearms three times and analyzed three different regions for each measurement. For each region cortical and trabecular parameters were determined. Reproducibility was assessed with respect to precision error (PE) and intraclass correlation coefficient (ICC). Reproducibility values were found to be best in all three regions for the full bone compartment with an average PE of 0.79%, followed by the cortical compartment (PE=1.19%) and the trabecular compartment with an average PE of 2.31%. The mechanical parameters showed similar reproducibility (PE=0.48%-2.93% for bone strength and stiffness, respectively). ICC showed a very high reproducibility of subject-specific measurements, ranging from 0.982 to 1.000, allowing secure identification of individual donors ranging from healthy to severely osteoporotic subjects. From these in vitro results we conclude that HR-pQCT derived morphometric and mechanical parameters are highly reproducible such that differences in bone structure and strength can be detected with a reproducibility error smaller than 3%; hence, the technique has a high potential to become a tool for detecting bone quality and bone competence of individual subjects.

  7. Spatial-Temporal Dynamics of High-Resolution Animal Networks: What Can We Learn from Domestic Animals?

    Directory of Open Access Journals (Sweden)

    Shi Chen

    Full Text Available Animal social network is the key to understand many ecological and epidemiological processes. We used real-time location system (RTLS to accurately track cattle position, analyze their proximity networks, and tested the hypothesis of temporal stationarity and spatial homogeneity in these networks during different daily time periods and in different areas of the pen. The network structure was analyzed using global network characteristics (network density, subgroup clustering (modularity, triadic property (transitivity, and dyadic interactions (correlation coefficient from a quadratic assignment procedure at hourly level. We demonstrated substantial spatial-temporal heterogeneity in these networks and potential link between indirect animal-environment contact and direct animal-animal contact. But such heterogeneity diminished if data were collected at lower spatial (aggregated at entire pen level or temporal (aggregated at daily level resolution. The network structure (described by the characteristics such as density, modularity, transitivity, etc. also changed substantially at different time and locations. There were certain time (feeding and location (hay that the proximity network structures were more consistent based on the dyadic interaction analysis. These results reveal new insights for animal network structure and spatial-temporal dynamics, provide more accurate descriptions of animal social networks, and allow more accurate modeling of multiple (both direct and indirect disease transmission pathways.

  8. Spatial-Temporal Dynamics of High-Resolution Animal Networks: What Can We Learn from Domestic Animals?

    Science.gov (United States)

    Chen, Shi; Ilany, Amiyaal; White, Brad J; Sanderson, Michael W; Lanzas, Cristina

    2015-01-01

    Animal social network is the key to understand many ecological and epidemiological processes. We used real-time location system (RTLS) to accurately track cattle position, analyze their proximity networks, and tested the hypothesis of temporal stationarity and spatial homogeneity in these networks during different daily time periods and in different areas of the pen. The network structure was analyzed using global network characteristics (network density), subgroup clustering (modularity), triadic property (transitivity), and dyadic interactions (correlation coefficient from a quadratic assignment procedure) at hourly level. We demonstrated substantial spatial-temporal heterogeneity in these networks and potential link between indirect animal-environment contact and direct animal-animal contact. But such heterogeneity diminished if data were collected at lower spatial (aggregated at entire pen level) or temporal (aggregated at daily level) resolution. The network structure (described by the characteristics such as density, modularity, transitivity, etc.) also changed substantially at different time and locations. There were certain time (feeding) and location (hay) that the proximity network structures were more consistent based on the dyadic interaction analysis. These results reveal new insights for animal network structure and spatial-temporal dynamics, provide more accurate descriptions of animal social networks, and allow more accurate modeling of multiple (both direct and indirect) disease transmission pathways.

  9. Identification and characterization of plasma cells in normal human bone marrow by high-resolution flow cytometry

    NARCIS (Netherlands)

    Terstappen, Leon W.M.M.; Johnsen, Steen; Segers-Nolten, Ine M.J.; Loken, Michael R.

    1990-01-01

    The low frequency of plasma cells and the lack of specific cell surface markers has been a major obstacle for a detailed characterization of plasma cells in normal human bone marrow. Multiparameter flow cytometry enabled the identification of plasma cells in normal bone marrow aspirates. The plasma

  10. Bone Microarchitecture and Estimated Strength in 499 Adult Danish Women and Men: A Cross-Sectional, Population-Based High-Resolution Peripheral Quantitative Computed Tomographic Study on Peak Bone Structure

    DEFF Research Database (Denmark)

    Hansen, Stinus; Shanbhogue, V.; Folkestad, L.;

    2014-01-01

    High-resolution peripheral quantitative computed tomography (HR-pQCT) allows in vivo assessment of cortical and trabecular bone mineral density (BMD), geometry, and microarchitecture at the distal radius and tibia in unprecedented detail. In this cross-sectional study, we provide normative...

  11. High Resolution Measurement of Rhizosphere Priming Effects and Temporal Variability of CO2 Fluxes under Zea Mays

    Science.gov (United States)

    Splettstößer, T.; Pausch, J.

    2016-12-01

    Plant induced increase of soil organic matter turnover rates contribute to carbon emissions in agricultural land use systems. In order to better understand these rhizosphere priming effects, we conducted an experiment, which enabled us to monitor CO2 fluxes under zea mays plants with high resolution. The experiment was conducted in a climate chamber where the plants were grown in thin, tightly sealed boxes for 40 days and CO2 efflux from soil was measured twice a day. 13C-CO2 was introduced to allow differentiation between plant and soil derived CO2.This enabled us to monitor root respiration and soil organic matter turnover in the early stages of plant growth and to highlight changes in soil CO2 emissions and priming effects between day and night. The measurements were conducted with a PICARRO G2131-I δ13C high-precision isotopic CO2 Analyzer (PICARRO INC.) utilizing an automated valve system governed by a CR1000 data logger (Campbell Scientific). After harvest roots and shoots were analyzed for 13C content. Microbial biomass, root length density and enzymatic activities in soil were measured and linked to soil organic matter turnover rates. In order to visualize the spatial distribution of carbon allocation to the root system a few plants were additionally labeled with 14C and 14C distribution was monitored by 14C imaging of the root systems over 4 days. Based on the 14C distribution a grid was chosen and the soil was sampled from each square of the grid to investigate the impact of carbon allocation hotspots on enzymatic activities and microbial biomass. First initial results show an increase of soil CO2 efflux in the night periods, whereby the contribution of priming is not fully analyzed yet. Additionally, root tips were identified as hotspots of short term carbon allocation via 14C imaging and an in increase in microbial biomass could be measured in this regions. The full results will be shown at AGU 2016.

  12. Temporal bone chondroblastoma totally invisible on MRI.

    Science.gov (United States)

    Hiraumi, Harukazu; Arakawa, Yoshiki; Yamamoto, Norio; Sakamoto, Tatsunori; Ito, Juichi

    2016-08-01

    We report a case of temporal bone chondroblastoma that was totally invisible on MRI. The patient was a 64-year-old man who presented with several months history of vertigo. The CT scan with bone window setting showed destruction of the temporomandibular joint, the floor of the middle cranial fossa, and the superior semicircular canal. Calcific foci were seen within the tumor. On MR imaging, the tumor, situating mainly medial to the temporomandibular joint, showed no signal on both T1- and T2-weighted images. The tumor was not enhanced with gadolinium. In summary, the tumor was totally signal negative or "invisible" on pre- and postcontrast T1- and T2-weighted images. The tumor was resected through transpetrosal - transzygomatic approach.

  13. Investigation of spatial resolution and temporal performance of SAPHIRE (scintillator avalanche photoconductor with high resolution emitter readout) with integrated electrostatic focusing

    Science.gov (United States)

    Scaduto, David A.; Lubinsky, Anthony R.; Rowlands, John A.; Kenmotsu, Hidenori; Nishimoto, Norihito; Nishino, Takeshi; Tanioka, Kenkichi; Zhao, Wei

    2014-03-01

    We have previously proposed SAPHIRE (scintillator avalanche photoconductor with high resolution emitter readout), a novel detector concept with potentially superior spatial resolution and low-dose performance compared with existing flat-panel imagers. The detector comprises a scintillator that is optically coupled to an amorphous selenium photoconductor operated with avalanche gain, known as high-gain avalanche rushing photoconductor (HARP). High resolution electron beam readout is achieved using a field emitter array (FEA). This combination of avalanche gain, allowing for very low-dose imaging, and electron emitter readout, providing high spatial resolution, offers potentially superior image quality compared with existing flat-panel imagers, with specific applications to fluoroscopy and breast imaging. Through the present collaboration, a prototype HARP sensor with integrated electrostatic focusing and nano- Spindt FEA readout technology has been fabricated. The integrated electron-optic focusing approach is more suitable for fabricating large-area detectors. We investigate the dependence of spatial resolution on sensor structure and operating conditions, and compare the performance of electrostatic focusing with previous technologies. Our results show a clear dependence of spatial resolution on electrostatic focusing potential, with performance approaching that of the previous design with external mesh-electrode. Further, temporal performance (lag) of the detector is evaluated and the results show that the integrated electrostatic focusing design exhibits comparable or better performance compared with the mesh-electrode design. This study represents the first technical evaluation and characterization of the SAPHIRE concept with integrated electrostatic focusing.

  14. High resolution spatio-temporal mapping of NO2 pollution for estimating personal exposures of the Dutch population

    Science.gov (United States)

    Soenario, Ivan; Helbich, Marco; Schmitz, Oliver; Strak, Maciek; Hoek, Gerard; Karssenberg, Derek

    2017-04-01

    Air pollution has been associated with adverse health effects (e.g., cardiovascular and respiration diseases) in the urban environments. Therefore, the assessment of people's exposure to air pollution is central in epidemiological studies. The estimation of exposures on an individual level can be done by combining location information across space and over time with spatio-temporal data on air pollution concentrations. When detailed information on peoples' space-time paths (e.g. commuting patterns calculated by means of spatial routing algorithms or tracked through GPS) and peoples' major activity locations (e.g. home location, work location) are available, it is possible to calculate more precise personal exposure levels depending on peoples' individual space-time mobility patterns. This requires air pollution values not only at a high level of spatial accuracy and high temporal granularity but such data also needs to be available on a nation-wide scale. As current data is seriously limited in this respect, we introduce a novel data set of NO2 levels across the Netherlands. The provided NO2 concentrations are accessible on hourly timestamps on a 5 meter grid cell resolution for weekdays and weekends, and each month of the year. We modeled a single Land Use Regression model using a five year average of NO2 data from the Dutch NO2 measurement network consisting of N=46 sampling locations distributed over the country. Predictor variables for this model were selected in a data-driven manner using an Elastic Net and Best Subset Selection procedure from 70 candidate predictors including traffic, industry, infrastructure and population-based variables. Subsequently, to model NO2 for each time scale (hour, week, month), the LUR coefficients were fitted using the NO2 data, aggregated per time scale. Model validation was grounded on independent data collected in an ad hoc measurement campaign. Our results show a considerable difference in urban concentrations between

  15. Bilateral sudden sensorineural hearing loss following unilateral temporal bone fracture.

    Science.gov (United States)

    Hunchaisri, Niran

    2009-06-01

    Temporal bone fractures usually cause unilateral sensorineural hearing loss (SNHL) by fracture that violated otic capsule of that side. Bilateral SNHL from unilateral temporal bone fracture were rarely seen. Labyrinthine concussion was considered to be the pathogenesis in these cases. This article reports an additional case of bilateral SNHL from unilateral temporal bone fracture but in a different pattern of SNHL which may result from an occlusion of the internal auditory artery.

  16. A customized protocol to assess bone quality in the metacarpal head, metacarpal shaft and distal radius: a high resolution peripheral quantitative computed tomography precision study.

    Science.gov (United States)

    Feehan, Lynne; Buie, Helen; Li, Linda; McKay, Heather

    2013-12-24

    High Resolution-Peripheral Quantitative Computed Tomography (HR-pQCT) is an emerging technology for evaluation of bone quality in Rheumatoid Arthritis (RA). However, there are limitations with standard HR-pQCT imaging protocols for examination of regions of bone commonly affected in RA. We developed a customized protocol for evaluation of volumetric bone mineral density (vBMD) and microstructure at the metacarpal head (MH), metacarpal shaft (MS) and ultra-ultra-distal (UUD) radius; three sites commonly affected in RA. The purpose was to evaluate short-term measurement precision for bone density and microstructure at these sites. 12 non-RA participants, individuals likely to have no pre-existing bone damage, consented to participate [8 females, aged 23 to 71 y [median (IQR): 44 (28) y]. The custom protocol includes more comfortable/stable positioning and adapted cortical segmentation and direct transformation analysis methods. Dominant arm MH, MS and UUD radius scans were completed on day one; repeated twice (with repositioning) three to seven days later. Short-term precision for repeated measures was explored using intraclass correlational coefficient (ICC), mean coefficient of variation (CV%), root mean square coefficient of variation (RMSCV%) and least significant change (LSC%95). Bone density and microstructure precision was excellent: ICCs varied from 0.88 (MH2 trabecular number) to .99 (MS3 polar moment of inertia); CV% varied from 3 on 5 point scale. In our facility, this custom protocol extends the potential for in vivo HR-pQCT imaging to assess, with high precision, regional differences in bone quality at three sites commonly affected in RA. Our methods are easy to adopt and we recommend other users of HR-pQCT consider this protocol for further evaluations of its precision and feasibility in their imaging facilities.

  17. CT diagnosis and differential diagnosis of otodystrophic lesions of the temporal bone

    Energy Technology Data Exchange (ETDEWEB)

    D' Archambeau, O.; Parizel, P.M.; Schepper, A.M. De (Antwerp University Hospital (Belgium). Department of Radiology); Koekelkoren, E.; Van De Heyning, P. (Antwerp University Hospital (Belgium). Department of E.N.T.)

    The purpose of this study was to assess the diagnostic and differential diagnostic value of high-resolution computed tomography in the evaluation of temporal-bone dystrophies. The study group included 55 patients with osseous abnormalities of the temporal bone in general, and the labyrinthine capsule in particular. In 27 patients the CT scan revealed evidence of otodystrophic lesions. The CT findings in patients with otosclerosis (21 patients), osteogenesis imperfecta (two patients), fibrous dysplasia (one patient). Paget's disease (one patient) and osteoporosis (two patients) are described. The CT scans of 17 patients revealed secondary osseous lesions due to metastasis (five patients), post-inflammatory changes (10 patients) or labyrinthitis ossificans (two patients). Normal variants and congenital mineralization defects were diagnosed in nine patients, Down's syndrome in two. Our results indicate the importance of high-resolution computed tomography as the primary imaging modality in evaluating osseous lesions of the temporal bone and labyrinth. (author). 14 refs.; 13 figs; 2 tabs.

  18. Correlation among external auditory canal anomaly, temporal bone malformation, and hearing levels in patients with microtia.

    Science.gov (United States)

    Chen, Kun; Liu, Liu; Shi, Runjie; Wang, Peihua; Chen, Dong; Xiao, Hua

    2017-06-01

    We conducted a retrospective study to evaluate the relationship between external auditory canal (EAC) anomaly, temporal bone abnormality, and hearing levels using objective scoring systems in Chinese patients with microtia. The study population consisted of 106 ears of 94 Chinese patients (67 male and 27 female) aged 5 to 45 years (mean: 12.6) with microtia. The EAC abnormalities were classified into 4 types according to Schuknecht's criteria: type A, type B, type C, and type D. Developmental anomalies of the temporal bone were evaluated by Jahrsdoerfer computed tomography (CT) scoring system using high-resolution CT scans of the temporal bone. Temporal bone malformation parameters were divided into 4 subgroups: ossicular chain development, windows connected to the cochlea, aeration development of the middle ear, and facial nerve aberration. Hearing levels (air conduction and bone conduction) were examined. Outcomes parameters included correlation coefficients (r) and a number of other variables. The total points (10 points) and subtotal points related to ossicles (4 points), windows (2 points), aeration (2 points), and facial nerve (1 point) correlated inversely with the EAC abnormalities. The hearing levels (air conduction, r = 0.396, p serve as an indicator to determine whether a patient will be suitable for reconstructive surgery.

  19. Comparison of high-resolution peripheral quantitative computerized tomography with dual-energy X-ray absorptiometry for measuring bone mineral density.

    Science.gov (United States)

    Colt, E; Akram, M; Pi Sunyer, F X

    2017-06-01

    The objective of this study was to compare the measurement of areal bone mineral density (aBMD) by dual-energy X-ray absorptiometry (DXA) with the measurement of volumetric bone mineral density (vBMD) by high-resolution peripheral computerized tomography (HR-pQCT) in subjects with a wide range of body mass indices (BMI). We scanned the arms and legs of 49 premenopausal women, aged 21-45 years, with BMI from 18.5 to 46.5, by HR-pQCT and found that there was a nonsignificant change in vBMD associated with increased BMI, whereas aBMD (DXA) was associated with a positive significant increase. HR-pQCT scans a slice at the extremity of the tibia and radius, whereas DXA scans the entire leg and arm. The correlation coefficients (r) of BMD (DXA) of the legs with BMI were 0.552, PD100) of legs and arms measured by HR-pQCT with BMI, W and %fat were not significant. Although HR-pQCT and DXA scan different parts of the bone, the high r of BMD with BMI and low r of bone density measured by HR-pQCT with BMI suggest that BMD measured by DXA is artifactually increased in the presence of obesity.

  20. The relationship of bone properties using high resolution peripheral quantitative computed tomography to radiographic components of hip osteoarthritis.

    Science.gov (United States)

    Edwards, M H; Paccou, J; Ward, K A; Jameson, K A; Moss, C; Woolston, J; Javaid, M K; Cooper, C; Dennison, E M

    2017-09-01

    Positive associations between radiographic osteoarthritis (OA) and areal bone mineral density (BMD) have been demonstrated and appear strongest when bony features of OA are considered. To date, these associations have not been assessed using HRpQCT. A total of 318 participants (170 men and 148 women), aged 72.1-81.4 years from a non-selected cohort, underwent HRpQCT of the distal radius and tibia along with hip radiography. Differences in bone microarchitecture were assessed between those with and without osteophytes, sclerosis or joint space narrowing (JSN) in either hip. Men with osteophytes alone had significantly higher radial trabecular volumetric BMD (Tb.vBMD) and radial and tibial trabecular thickness (Tb.Th). Men with both sclerosis and osteophytes had significantly higher cortical volumetric BMD (Ct.vBMD) and cortical thickness (Ct.Th) at the distal tibia than those with osteophytes alone (P < 0.05). These relationships were maintained after adjustment for age and Body Mass Index (BMI), and were not replicated in women. Bone microarchitecture did not differ significantly in those with JSN from those without it in men or women. Our findings suggest higher Tb.vBMD and Tb.Th in men with osteophytosis but higher tibial Ct.vBMD and Ct.Th in men with hip joint sclerosis. These results do however require replication in other cohorts. Copyright © 2017 Osteoarthritis Research Society International. Published by Elsevier Ltd. All rights reserved.

  1. Bone geometry, density, and microarchitecture in the distal radius and tibia in adults with osteogenesis imperfecta type I assessed by high-resolution pQCT.

    Science.gov (United States)

    Folkestad, Lars; Hald, Jannie Dahl; Hansen, Stinus; Gram, Jeppe; Langdahl, Bente; Abrahamsen, Bo; Brixen, Kim

    2012-06-01

    Osteogenesis imperfecta (OI) is a hereditary disorder characterized by decreased biosynthesis or impaired morphology of type I collagen that leads to decreased bone mass and increased bone fragility. We hypothesized that patients with OI have altered bone microstructure and bone geometry. In this cross-sectional study we compared patients with type I OI to age- and gender-matched healthy controls. A total of 39 (13 men and 26 women) patients with OI, aged 53 (range, 21-77) years, and 39 controls, aged 53 (range, 21-77) years, were included in the study. Twenty-seven of the patients had been treated with bisphosphonates. High-resolution peripheral quantitative computed tomography (HR-pQCT) at the distal radius and distal tibia and dual-energy X-ray absorptiometry of total hip, femoral neck, trochanteric region, and the lumbar spine (L1-L4) were performed. The patients were shorter than the controls (159 ± 10 cm versus 170 ± 9 cm, p radius (p radius, total bone area was 5% lower in OI than in controls (p radius and tibia the number of trabeculae was lower in patients compared to the controls (35% and 38%, respectively, p radius (p < 0.001 at both sites) when compared with controls. We conclude that patients with type I OI have lower aBMD, vBMD, bone area, and trabecular number when compared with healthy age- and gender-matched controls.

  2. [Modern imaging of the temporal bone].

    Science.gov (United States)

    Kösling, S

    2017-06-01

    This article describes the current significance of computed tomography (CT), magnetic resonance imaging (MRI), cone beam CT, digital subtraction angiography (DSA), and special X‑rays in the diagnostics of temporal bone diseases. The latter is obsolete for diagnostic intentions. Possibilities and limitations in terms of detection and/or depiction of the extent of inflammatory, traumatic, tumorous, and postoperative pathologies are discussed. A concrete question and conveyance of clinical findings influence the choice of the method to be applied in the individual case. Malformations of the middle ear can only be detected noninvasively by CT or cone beam CT. These are also the methods that may support the diagnosis of otosclerosis in clinically unclear cases. MRI is the method of choice for pathologies of the inner ear and internal auditory canal, including inner ear malformations. At present, only in few institutions is a successful visualization of endolymphatic hydrops in Menière's disease realized.

  3. Reconstructing Large-Scale Brain Resting-State Networks from High-Resolution EEG: Spatial and Temporal Comparisons with fMRI.

    Science.gov (United States)

    Yuan, Han; Ding, Lei; Zhu, Min; Zotev, Vadim; Phillips, Raquel; Bodurka, Jerzy

    2016-03-01

    Functional magnetic resonance imaging (fMRI) studies utilizing measures of hemodynamic signal, such as the blood oxygenation level-dependent (BOLD) signal, have discovered that resting-state brain activities are organized into multiple large-scale functional networks, coined as resting-state networks (RSNs). However, an important limitation of the available fMRI studies is that hemodynamic signals only provide an indirect measure of the neuronal activity. In contrast, electroencephalography (EEG) directly measures electrophysiological activity of the brain. However, little is known about the brain-wide organization of such spontaneous neuronal population signals at the resting state. It is not entirely clear if or how the network structure built upon slowly fluctuating hemodynamic signals is represented in terms of fast, dynamic, and spontaneous neuronal activity. In this study, we investigated the electrophysiological representation of RSNs from simultaneously acquired EEG and fMRI data in the resting human brain. We developed a data-driven analysis approach that reconstructed multiple large-scale electrophysiological networks from high-resolution EEG data alone. The networks derived from EEG were then compared with RSNs independently derived from simultaneously acquired fMRI in their spatial structures as well as temporal dynamics. Results reveal spatially and temporally specific electrophysiological correlates for the fMRI-RSNs. Findings suggest that the spontaneous activity of various large-scale cortical networks is reflected in macroscopic EEG potentials.

  4. Bilateral mesial temporal sclerosis: MRI with high-resolution fast spin-echo and fluid-attenuated inversion-recovery sequences

    Energy Technology Data Exchange (ETDEWEB)

    Oppenheim, C.; Dormont, D.; Lehericy, S.; Marsault, C. [Dept. of Neuroradiology, Groupe Hospitalier Pite-Salpetriere, Paris (France); Hasboun, D. [Dept. of Neuroradiology, Groupe Hospitalier Pite-Salpetriere, Paris (France)]|[Dept. of Neurology, Paris VI Univ. (France); Bazin, B.; Samson, S.; Baulac, M. [Dept. of Neurology, Paris VI Univ. (France)

    1999-07-01

    We report a retrospective analysis of MRI in 206 patients with intractable seizures and describe the findings in bilateral mesial temporal sclerosis (MTS) on fast spin-echo (FSE) and fast fluid-attenuated inversion-recovery (fFLAIR) sequences. Criteria for MTS were atrophy, signal change and loss of the digitations of the head of the hippocampus. In patients with bilateral MRI signs of MTS, correlation with clinical electro, volumetric MRI data and neuropsychological tests, when available, was performed. Bilateral MTS was observed in seven patients. Bilateral loss of the digitations and signal change of fFLAIR was seen in all seven. In three, bilateral atrophy was obvious. In two patients, mild bilateral atrophy was observed and in two others, the hippocampi were: asymmetrical, with obvious atrophy on only one side. Volumetric data confirmed bilateral symmetrical atrophy in five patients, and volumes were at the lowest of the normal range in other two. The EEG showed temporal abnormalities in all patients, unilateral in five and bilateral in two. All patients had memory impairment and neuropsychological data confirmed visual and verbal memory deficits; two patients failed the Wada test on both sides. High-resolution T2-weighted FSE and fFLAIR sequences allow diagnosis of bilateral MTS, which has important therapeutic and prognostic implications. (orig.)

  5. Radiation injury to the temporal bone

    Energy Technology Data Exchange (ETDEWEB)

    Guida, R.A.; Finn, D.G.; Buchalter, I.H.; Brookler, K.H.; Kimmelman, C.P. (New York Eye and Ear Infirmary/New York Medical College (USA))

    1990-01-01

    Osteoradionecrosis of the temporal bone is an unusual sequela of radiation therapy to the head and neck. Symptoms occur many years after the radiation is administered, and progression of the disease is insidious. Hearing loss (sensorineural, conductive, or mixed), otalgia, otorrhea, and even gross tissue extrusion herald this condition. Later, intracranial complications such as meningitis, temporal lobe or cerebellar abscess, and cranial neuropathies may occur. Reported here are five cases of this rare malady representing varying degrees of the disease process. They include a case of radiation-induced necrosis of the tympanic ring with persistent squamous debris in the external auditory canal and middle ear. Another case demonstrates the progression of radiation otitis media to mastoiditis with bony sequestration. Further progression of the disease process is seen in a third case that evolved into multiple cranial neuropathies from skull base destruction. Treatment includes systemic antibiotics, local wound care, and debridement in cases of localized tissue involvement. More extensive debridement with removal of sequestrations, abscess drainage, reconstruction with vascularized tissue from regional flaps, and mastoid obliteration may be warranted for severe cases. Hyperbaric oxygen therapy has provided limited benefit.

  6. Utility of the inspiratory phase in high-resolution computed tomography evaluations of pediatric patients with bronchiolitis obliterans after allogeneic bone marrow transplant: reducing patient radiation exposure

    Directory of Open Access Journals (Sweden)

    Paulo Henrique Togni Filho

    Full Text Available Abstract Objective: To evaluate the utility of the inspiratory phase in high-resolution computed tomography (HRCT of the chest for the diagnosis of post-bone marrow transplantation bronchiolitis obliterans. Materials and Methods: This was a retrospective, observational, cross-sectional study. We selected patients of either gender who underwent bone marrow transplantation and chest HRCT between March 1, 2002 and December 12, 2014. Ages ranged from 3 months to 20.7 years. We included all examinations in which the HRCT was performed appropriately. The examinations were read by two radiologists, one with extensive experience in pediatric radiology and another in the third year of residency, who determined the presence or absence of the following imaging features: air trapping, bronchiectasis, alveolar opacities, nodules, and atelectasis. Results: A total of 222 examinations were evaluated (mean, 5.4 ± 4.5 examinations per patient. The expiratory phase findings were comparable to those obtained in the inspiratory phase, except in one patient, in whom a small uncharacteristic nodule was identified only in the inspiratory phase. Air trapping was identified in a larger number of scans in the expiratory phase than in the inspiratory phase, as was atelectasis, although the difference was statistically significant only for air trapping. Conclusion: In children being evaluated for post-bone marrow transplantation bronchiolitis obliterans, the inspiratory phase can be excluded from the chest HRCT protocol, thus reducing by half the radiation exposure in this population.

  7. Distal radius plate of CFR-PEEK has minimal effect compared to titanium plates on bone parameters in high-resolution peripheral quantitative computed tomography: a pilot study.

    Science.gov (United States)

    de Jong, Joost J A; Lataster, Arno; van Rietbergen, Bert; Arts, Jacobus J; Geusens, Piet P; van den Bergh, Joop P W; Willems, Paul C

    2017-02-27

    Carbon-fiber-reinforced poly-ether-ether-ketone (CFR-PEEK) has superior radiolucency compared to other orthopedic implant materials, e.g. titanium or stainless steel, thus allowing metal-artifact-free postoperative monitoring by computed tomography (CT). Recently, high-resolution peripheral quantitative CT (HRpQCT) proved to be a promising technique to monitor the recovery of volumetric bone mineral density (vBMD), micro-architecture and biomechanical parameters in stable conservatively treated distal radius fractures. When using HRpQCT to monitor unstable distal radius fractures that require volar distal radius plating for fixation, radiolucent CFR-PEEK plates may be a better alternative to currently used titanium plates to allow for reliable assessment. In this pilot study, we assessed the effect of a volar distal radius plate made from CFR-PEEK on bone parameters obtained from HRpQCT in comparison to two titanium plates. Plates were instrumented in separate cadaveric human fore-arms (n = 3). After instrumentation and after removal of the plates duplicate HRpQCT scans were made of the region covered by the plate. HRpQCT images were visually checked for artifacts. vBMD, micro-architectural and biomechanical parameters were calculated, and compared between the uninstrumented and instrumented radii. No visible image artifacts were observed in the CFR-PEEK plate instrumented radius, and errors in bone parameters ranged from -3.2 to 2.6%. In the radii instrumented with the titanium plates, severe image artifacts were observed and errors in bone parameters ranged between -30.2 and 67.0%. We recommend using CFR-PEEK plates in longitudinal in vivo studies that monitor the healing process of unstable distal radius fractures treated operatively by plating or bone graft ingrowth.

  8. Vascular anomalies, sutures and small canals of the temporal bone on axial CT

    Energy Technology Data Exchange (ETDEWEB)

    Koesling, Sabrina [Department of Diagnostic Radiology, University of Halle, E. Grube Str. 40, 06097 Halle (Germany)]. E-mail: sabrina.koesling@medizin.uni-halle.de; Kunkel, Petra [Department of Diagnostic Radiology, University of Leipzig (Germany); Schul, Thomas [Department of Diagnostic Radiology, University of Leipzig (Germany)

    2005-06-01

    Purpose: Subtle bony structures, small canals and fine sutures cause sometimes problems in the analysis of CTs of the temporal bone. The aim of this study was: to analyze the visibility of subtle structures and to estimate the incidence of vascular anomalies. Patients and method: We retrospectively analyzed axial scans of 223 high-resolution CTs of the temporal bone obtained as single slice or spiral CT with 1 mm slice thickness. All CTs had clinical indications. Two experienced radiologists studied CTs regarding the visibility of the fine sutures, fissures and small canals and the occurrence of vascular anomalies. Results: The following structures were seen commonly: sphenosquamosal suture (76%), arcuate artery canal (93%), vestibular aqueduct (89%), mastoid emissary vein (82%), singular canal (56%). Not so commonly were observed: tympanosquamosal suture (31%), mastoid canaliculus (28%), lateral sigmoid sinus (28%), petrotympanic fissure (24%), tympanomastoid suture (10%). Seldom we identified: the inferior tympanic canaliculus (6%), high jugular bulb (6%), anterior sigmoid sinus (5%), dehiscent internal carotid artery canal (2%), persistent petrosquamosal sinus (1%), dehiscent jugular bulb (1%). Persistent stapedial artery, aberrant internal carotid artery, dehiscent jugular bulb, high jugular bulb with diverticulum, anterior and dehiscent sigmoid sinus were detected in below 1% of the analyzed temporal bones. The frequency of asymmetry of the jugular foramen, which varied between 3% and 42%, depended on different criterions of size. Conclusion: A profound knowledge of normal anatomy and anomalies of the temporal bone avoids misinterpretation as pathological lesions and iatrogenic bleedings.

  9. Temporal Variability in Vertical Groundwater Fluxes and the Effect of Solar Radiation on Streambed Temperatures Based on Vertical High Resolution Distributed Temperature Sensing

    Science.gov (United States)

    Sebok, E.; Karan, S.; Engesgaard, P. K.; Duque, C.

    2013-12-01

    Due to its large spatial and temporal variability, groundwater discharge to streams is difficult to quantify. Methods using vertical streambed temperature profiles to estimate vertical fluxes are often of coarse vertical spatial resolution and neglect to account for the natural heterogeneity in thermal conductivity of streambed sediments. Here we report on a field investigation in a stream, where air, stream water and streambed sediment temperatures were measured by Distributed Temperature Sensing (DTS) with high spatial resolution to; (i) detect spatial and temporal variability in groundwater discharge based on vertical streambed temperature profiles, (ii) study the thermal regime of streambed sediments exposed to different solar radiation influence, (iii) describe the effect of solar radiation on the measured streambed temperatures. The study was carried out at a field site located along Holtum stream, in Western Denmark. The 3 m wide stream has a sandy streambed with a cobbled armour layer, a mean discharge of 200 l/s and a mean depth of 0.3 m. Streambed temperatures were measured with a high-resolution DTS system (HR-DTS). By helically wrapping the fiber optic cable around two PVC pipes of 0.05 m and 0.075 m outer diameter over 1.5 m length, temperature measurements were recorded with 5.7 mm and 3.8 mm vertical spacing, respectively. The HR-DTS systems were installed 0.7 m deep in the streambed sediments, crossing both the sediment-water and the water-air interface, thus yielding high resolution water and air temperature data as well. One of the HR-DTS systems was installed in the open stream channel with only topographical shading, while the other HR-DTS system was placed 7 m upstream, under the canopy of a tree, thus representing the shaded conditions with reduced influence of solar radiation. Temperature measurements were taken with 30 min intervals between 16 April and 25 June 2013. The thermal conductivity of streambed sediments was calibrated in a 1D flow

  10. Osteonecrosis Diagnosed on MR Images of the Knee. Relationship to reduced bone mineral density determined by high resolution peripheral quantitative CT

    Energy Technology Data Exchange (ETDEWEB)

    Zanetti, M.; Hodler, J. [Orthopedic Univ. Hospital Balgrist, Zuerich (Switzerland). Dept. of Radiology; Romero, J. [Orthopedic Univ. Hospital Balgrist, Zuerich (Switzerland). Dept. of Orthopedic Surgery; Dambacher, M.A. [Univ. Hospital Balgrist, Zuerich (Switzerland). Inst. of Physical Medicine and Rheumatology

    2003-09-01

    Purpose: To evaluate if osteonecrosis diagnosed on MR images of the knee relates to reduced bone mineral density (BMD) and may be caused by an insufficiency fracture. Material and Methods: Thirty-two consecutive patients (8 men, 24 women; age range 27-82 years, mean 62 years) with MR findings of osteonecrosis of the femoral or tibial condyle were prospectively included. Trabecular and cortical BMD were measured with high resolution peripheral quantitative CT in the non-dominant distal radius and the tibia of the involved extremity. One tibia was not measured due to posttraumatic deformity. Results: The mean trabecular BMD of the radius was 81% of the young-adult average peak BMD (range 19-160%). The mean cortical BMD in the radius was 86% (range 63-108%). The mean trabecular BMD in the tibia was 92% (range 28-160%). The mean cortical BMD in the tibia was 86% (range 49-132%). The values of the trabecular bone of the distal radius (tibia) were normal in 11 (15) patients, osteopenic in 12 (4), and osteoporotic in 9 (12), respectively. The cortical bone values of the distal radius (tibia) were normal in 12 (13) patients, osteopenic in 12 (12), and osteoporotic in 8 (6), respectively. Conclusion: Osteoporosis and osteopenia are commonly found in patients with osteonecrosis of the knee as diagnosed on MR images. This indicates that for some patients an insufficiency mechanism may be responsible for the MR findings. However, in the patients with normal bone density other reasons for osteonecrosis may be present.

  11. Cluster analysis of bone microarchitecture from high resolution peripheral quantitative computed tomography demonstrates two separate phenotypes associated with high fracture risk in men and women.

    Science.gov (United States)

    Edwards, M H; Robinson, D E; Ward, K A; Javaid, M K; Walker-Bone, K; Cooper, C; Dennison, E M

    2016-07-01

    Osteoporosis is a major healthcare problem which is conventionally assessed by dual energy X-ray absorptiometry (DXA). New technologies such as high resolution peripheral quantitative computed tomography (HRpQCT) also predict fracture risk. HRpQCT measures a number of bone characteristics that may inform specific patterns of bone deficits. We used cluster analysis to define different bone phenotypes and their relationships to fracture prevalence and areal bone mineral density (BMD). 177 men and 159 women, in whom fracture history was determined by self-report and vertebral fracture assessment, underwent HRpQCT of the distal radius and femoral neck DXA. Five clusters were derived with two clusters associated with elevated fracture risk. "Cluster 1" contained 26 women (50.0% fractured) and 30 men (50.0% fractured) with a lower mean cortical thickness and cortical volumetric BMD, and in men only, a mean total and trabecular area more than the sex-specific cohort mean. "Cluster 2" contained 20 women (50.0% fractured) and 14 men (35.7% fractured) with a lower mean trabecular density and trabecular number than the sex-specific cohort mean. Logistic regression showed fracture rates in these clusters to be significantly higher than the lowest fracture risk cluster [5] (pcluster 5 in women in cluster 1 and 2 (pcluster 2 (pclusters in both men and women which may differ in etiology and response to treatment. As cluster 1 in men does not have low areal BMD, these men may not be identified as high risk by conventional DXA alone. Copyright © 2016. Published by Elsevier Inc.

  12. Multi-Temporal Land-Cover Classification of Agricultural Areas in Two European Regions with High Resolution Spotlight TerraSAR-X Data

    Directory of Open Access Journals (Sweden)

    Sylvia Herrmann

    2011-04-01

    Full Text Available Functioning ecosystems offer multiple services for human well-being (e.g., food, freshwater, fiber. Agriculture provides several of these services but also can cause negative impacts. Thus, it is essential to derive up-to-date information about agricultural land use and its change. This paper describes the multi-temporal classification of agricultural land use based on high resolution spotlight TerraSAR-X images. A stack of l4 dual-polarized radar images taken during the vegetation season have been used for two different study areas (North of Germany and Southeast Poland. They represent extremely diverse regions with regard to their population density, agricultural management, as well as geological and geomorphological conditions. Thereby, the transferability of the classification method for different regions is tested. The Maximum Likelihood classification is based on a high amount of ground truth samples. Classification accuracies differ in both regions. Overall accuracy for all classes for the German area is 61.78% and 39.25% for the Polish region. Accuracies improved notably for both regions (about 90% when single vegetation classes were merged into groups of classes. Such regular land use classifications, applicable for different European agricultural sites, can serve as basis for monitoring systems for agricultural land use and its related ecosystems.

  13. Temporal Bone Fracture Causing Superior Semicircular Canal Dehiscence

    Directory of Open Access Journals (Sweden)

    Kevin A. Peng

    2014-01-01

    Full Text Available Importance. Superior semicircular canal dehiscence (SCD is a third window lesion of the inner ear causing symptoms of vertigo, autophony, tinnitus, and hearing loss. A “two-hit” hypothesis has traditionally been proposed, whereby thinly developed bone overlying the superior canal is disrupted by a sudden change in intracranial pressure. Although the symptoms of SCD may be precipitated by head injury, no previous reports have described a temporal bone fracture directly causing SCD. Observations. Two patients sustained temporal bone fractures after closed head trauma, and developed unilateral otologic symptoms consistent with SCD. In each instance, computed tomography imaging revealed fractures extending through the bony roof of the superior semicircular canal. Conclusions and Relevance. Temporal bone fractures, which are largely treated nonoperatively, have not previously been reported to cause SCD. As it is a potentially treatable entity, SCD resulting from temporal bone fracture must be recognized as a possibility and diagnosed promptly if present.

  14. Cadaveric Temporal Bone Dissection: Is It Obsolete Today?

    Directory of Open Access Journals (Sweden)

    Naik, Sulabha M.

    2014-01-01

    Full Text Available Introduction Traditionally, surgical training in otology, is imparted by dissecting harvested human cadaveric temporal bones. However, maintenance of a cadaveric temporal bone laboratory is expensive and carries risk of exposure to infection. In recent times, other modalities of training are gaining ground and are likely to eventually replace cadaveric temporal bone dissection altogether. Objectives Other alternative methods of training are emerging. New technology like simulation and virtual reality as high-fidelity, safer alternatives, are making rapid strides as teaching tools. Other options are the use of animal temporal bones as teaching tools. The advantages of these are compared. Data Synthesis None of these modalities can replicate the innumerable anatomical variations which are a characteristic feature of the human temporal bone. A novice surgeon not only needs exposure to surgical anatomy and it's variations but also needs to develop hand-eye coordination skills to gain expertise. Conclusion Deliberate practice on human cadaveric temporal bones only, will confer both mastery in anatomy and surgical technique. The human cadaveric temporal bone is ideal simulator for training in otology.

  15. Temporal bone dissection practice using a chicken egg.

    Science.gov (United States)

    Meléndez García, José Manuel; Araujo Da Costa, Ana Sofía; Rivera Schmitz, Teresa; Chiesa Estomba, Carlos Miguel; Hamdan Zavarce, Miriam Ileana

    2014-07-01

    Temporal bone drilling practice constitutes an essential stage in training for the surgical approach to this complex anatomic structure. To facilitate adaptation and surgical skills in otologic surgery, we recall the easy cost-effective practice of drilling a chicken egg. The resident in training must master the use of the surgical microscope, the burr, and fine drilling instruments used in dissection. Animal models, plastic temporal bones, prototyped temporal bones, and virtual reality temporal bones have all been used. This article describes a method of training residents' otologic skills by drilling a chicken egg. We used basic support materials found in a typical temporal bone dissection laboratory, with a surgical microscope, a desk, and a drilling system. Practice includes drilling and dissection of the eggshell, preserving the natural eggshell membrane. Learning temporal bone drilling on an egg, using basic materials, allows the surgeon to simulate surgery on a physical model using the same instrumentation that is used in surgery, obviating the need for laboratory conditions required for cadaveric dissection. Simulation is emerging as a mandatory component of surgical training. The egg is an excellent cost-effective model for drilling and dissection training and helps in improving surgical skills, enables learning of fine motor skills, and allows repeated practice. Although this method of training does help one control a drill and manual instrumentation, it does not help with temporal bone anatomy knowledge.

  16. Dynamics in mangroves assessed by high-resolution and multi-temporal satellite data: a case study in Zhanjiang Mangrove National Nature Reserve (ZMNNR), P. R. China

    Science.gov (United States)

    Leempoel, K.; Satyaranayana, B.; Bourgeois, C.; Zhang, J.; Chen, M.; Wang, J.; Bogaert, J.; Dahdouh-Guebas, F.

    2013-08-01

    Mangrove forests are declining across the globe, mainly because of human intervention, and therefore require an evaluation of their past and present status (e.g. areal extent, species-level distribution, etc.) to implement better conservation and management strategies. In this paper, mangrove cover dynamics at Gaoqiao (P. R. China) were assessed through time using 1967, 2000 and 2009 satellite imagery (sensors Corona KH-4B, Landsat ETM+, GeoEye-1 respectively). Firstly, multi-temporal analysis of satellite data was undertaken, and secondly biotic and abiotic differences were analysed between the different mangrove stands, assessed through a supervised classification of a high-resolution satellite image. A major decline in mangrove cover (-36%) was observed between 1967 and 2009 due to rice cultivation and aquaculture practices. Moreover, dike construction has prevented mangroves from expanding landward. Although a small increase of mangrove area was observed between 2000 and 2009 (+24%), the ratio mangrove / aquaculture kept decreasing due to increased aquaculture at the expense of rice cultivation in the vicinity. From the land-use/cover map based on ground-truth data (5 × 5 m plot-based tree measurements) (August-September, 2009) as well as spectral reflectance values (obtained from pansharpened GeoEye-1), both Bruguiera gymnorrhiza and small Aegiceras corniculatum are distinguishable at 73-100% accuracy, whereas tall A. corniculatum was correctly classified at only 53% due to its mixed vegetation stands with B. gymnorrhiza (overall classification accuracy: 85%). In the case of sediments, sand proportion was significantly different between the three mangrove classes. Overall, the advantage of very high resolution satellite images like GeoEye-1 (0.5 m) for mangrove spatial heterogeneity assessment and/or species-level discrimination was well demonstrated, along with the complexity to provide a precise classification for non-dominant species (e.g. Kandelia obovata

  17. Dynamics in mangroves assessed by high-resolution and multi-temporal satellite data: a case study in Zhanjiang Mangrove National Nature Reserve (ZMNNR, P. R. China

    Directory of Open Access Journals (Sweden)

    K. Leempoel

    2013-08-01

    Full Text Available Mangrove forests are declining across the globe, mainly because of human intervention, and therefore require an evaluation of their past and present status (e.g. areal extent, species-level distribution, etc. to implement better conservation and management strategies. In this paper, mangrove cover dynamics at Gaoqiao (P. R. China were assessed through time using 1967, 2000 and 2009 satellite imagery (sensors Corona KH-4B, Landsat ETM+, GeoEye-1 respectively. Firstly, multi-temporal analysis of satellite data was undertaken, and secondly biotic and abiotic differences were analysed between the different mangrove stands, assessed through a supervised classification of a high-resolution satellite image. A major decline in mangrove cover (−36% was observed between 1967 and 2009 due to rice cultivation and aquaculture practices. Moreover, dike construction has prevented mangroves from expanding landward. Although a small increase of mangrove area was observed between 2000 and 2009 (+24%, the ratio mangrove / aquaculture kept decreasing due to increased aquaculture at the expense of rice cultivation in the vicinity. From the land-use/cover map based on ground-truth data (5 × 5 m plot-based tree measurements (August–September, 2009 as well as spectral reflectance values (obtained from pansharpened GeoEye-1, both Bruguiera gymnorrhiza and small Aegiceras corniculatum are distinguishable at 73–100% accuracy, whereas tall A. corniculatum was correctly classified at only 53% due to its mixed vegetation stands with B. gymnorrhiza (overall classification accuracy: 85%. In the case of sediments, sand proportion was significantly different between the three mangrove classes. Overall, the advantage of very high resolution satellite images like GeoEye-1 (0.5 m for mangrove spatial heterogeneity assessment and/or species-level discrimination was well demonstrated, along with the complexity to provide a precise classification for non-dominant species (e

  18. CT-scanning of ancient Greenlandic Inuit temporal bones

    DEFF Research Database (Denmark)

    Homøe, P; Lynnerup, N; Videbaek, H

    1992-01-01

    bones. The CT-scans showed sclerosing and obliteration of the air cells and even destruction of the cellular septae, and a high degree of irregularity of the cells. Sclerosing of the surrounding bone tissue was also found. The findings in one cranium were dubious and could both be regarded...... as a congenital malformation or an infection in infanthood. CT-scan confirms and even adds to the results of conventional X-ray of temporal bones making hypotheses of paleopathology more reliable. The findings also support the environmental theory of pneumatization of the air cell system in the temporal bones....

  19. Surgical treatment and outcomes of temporal bone chondroblastoma.

    Science.gov (United States)

    Moon, In Seok; Kim, Jin; Lee, Ho-Ki; Lee, Won-Sang

    2008-12-01

    Chondroblastoma is an uncommon primary benign bone tumor that usually arises in the epiphyses of the long bones. Temporal bone chondroblastoma is a rare primary bone tumor that affects the floor of the middle cranial fossa and temporomandibular joint (TMJ). The biological nature of temporal bone chondroblastoma is occasionally aggressive because of local invasion and is known to have a high recurrence after curettage. Therefore, complete resection is recommended. However, the literature provides little information regarding long-term surgical outcomes and complications after surgical resection. The authors have retrospectively analyzed four cases of temporal bone chondroblastoma that had been completely excised by a single surgeon with an eventual long-term follow-up. A single surgeon operated on four patients, two males and two females, with a mean age of 34 years, at the Department of Otorhinolaryngology, Severance Hospital. In all cases, the tumor involved the middle cranial fossa dura and the mandibular fossa with variable degree of infiltration. All patients have had no tumor recurrence to date (mean follow-up period of 5 years). Complete surgical resection of the temporal bone chondroblastoma is the gold standard for treatment. Precise preoperative image evaluation of tumor extension and proper management of the dura mater and temporomandibular joint (TMJ) are the major important features in complete surgical removal that minimize complications in temporal bone chondroblastoma treatment.

  20. [CT findings of the temporal bones in Waardenburg's syndrome].

    Science.gov (United States)

    Irie, K; Ogata, H; Mitsudome, A

    1990-05-01

    We reported three cases of Waardenburg's syndrome and discussed CT findings of the temporal bones. Two cases of these patients were mother and daughter. Case 1, a two-year-old girl, had lateral displacement of the medial canthi, a broad nasal root, hetero-chromic iridis, left ptosis, albinotic fundus, and bilateral congenital deafness. CT findings of the temporal bones showed enlarged vestibules, short lateral semicircular canal, and absent right posterior semicircular canal. The mother had congenital deafness, heterochromia iridis, and a white forelock and showed similar abnormal CT findings of the temporal bones. Case 2, a one-year-old boy, had lateral displacement of the medial canthi, a broad nasal root, partial heterochromia iridis, albinotic fundus, and bilateral congenital deafness. CT findings of the temporal bones showed enlarged vestibules and absence of semicircular canals except the right lateral semicircular canal. These cases were diagnosed as Waardenburg's syndrome on the basis of the characteristic features.

  1. Polarity and temporality of high-resolution y-chromosome distributions in India identify both indigenous and exogenous expansions and reveal minor genetic influence of Central Asian pastoralists.

    Science.gov (United States)

    Sengupta, Sanghamitra; Zhivotovsky, Lev A; King, Roy; Mehdi, S Q; Edmonds, Christopher A; Chow, Cheryl-Emiliane T; Lin, Alice A; Mitra, Mitashree; Sil, Samir K; Ramesh, A; Usha Rani, M V; Thakur, Chitra M; Cavalli-Sforza, L Luca; Majumder, Partha P; Underhill, Peter A

    2006-02-01

    Although considerable cultural impact on social hierarchy and language in South Asia is attributable to the arrival of nomadic Central Asian pastoralists, genetic data (mitochondrial and Y chromosomal) have yielded dramatically conflicting inferences on the genetic origins of tribes and castes of South Asia. We sought to resolve this conflict, using high-resolution data on 69 informative Y-chromosome binary markers and 10 microsatellite markers from a large set of geographically, socially, and linguistically representative ethnic groups of South Asia. We found that the influence of Central Asia on the pre-existing gene pool was minor. The ages of accumulated microsatellite variation in the majority of Indian haplogroups exceed 10,000-15,000 years, which attests to the antiquity of regional differentiation. Therefore, our data do not support models that invoke a pronounced recent genetic input from Central Asia to explain the observed genetic variation in South Asia. R1a1 and R2 haplogroups indicate demographic complexity that is inconsistent with a recent single history. Associated microsatellite analyses of the high-frequency R1a1 haplogroup chromosomes indicate independent recent histories of the Indus Valley and the peninsular Indian region. Our data are also more consistent with a peninsular origin of Dravidian speakers than a source with proximity to the Indus and with significant genetic input resulting from demic diffusion associated with agriculture. Our results underscore the importance of marker ascertainment for distinguishing phylogenetic terminal branches from basal nodes when attributing ancestral composition and temporality to either indigenous or exogenous sources. Our reappraisal indicates that pre-Holocene and Holocene-era--not Indo-European--expansions have shaped the distinctive South Asian Y-chromosome landscape.

  2. The temporal response of bone to unloading

    Science.gov (United States)

    Globus, R. K.; Bikle, D. D.; Morey-Holton, E.

    1984-01-01

    Rats were suspended by their tails with the forelimbs bearing the weight load to simulate the weightlessness of space flight. Growth in bone mass ceased by 1 week in the hindlimbs and lumbar vertebrae in growing rats, while growth in the forelimbs and cervical vertebrae remained unaffected. The effects of selective skeletal unloading on bone formation during 2 weeks of suspension was investigated using radio iostope incorporation (with Ca-45 and H-3 proline) and histomorphometry (with tetracycline labeling). The results of these studies were confirmed by histomorphometric measurements of bone formation using triple tetracycline labeling. This model of simulated weightlessness results in an initial inhibition of bone formation in the unloaded bones. This temporary cessation of bone formation is followed in the accretion of bone mass, which then resumes at a normal rate by 14 days, despite continued skeletal unloading. This cycle of inhibition and resumption of bone formation has profound implication for understanding bone dynamics durng space flight, immobilization, or bed rest and offers an opportunity to study the hormonal and mechanical factors that regulate bone formation.

  3. A New Hybrid Spatio-temporal Model for Estimating Daily Multi-year PM2.5 Concentrations Across Northeastern USA Using High Resolution Aerosol Optical Depth Data

    Science.gov (United States)

    Kloog, Itai; Chudnovsky, Alexandra A.; Just, Allan C.; Nordio, Francesco; Koutrakis, Petros; Coull, Brent A.; Lyapustin, Alexei; Wang, Yujie; Schwartz, Joel

    2014-01-01

    The use of satellite-based aerosol optical depth (AOD) to estimate fine particulate matter PM(sub 2.5) for epidemiology studies has increased substantially over the past few years. These recent studies often report moderate predictive power, which can generate downward bias in effect estimates. In addition, AOD measurements have only moderate spatial resolution, and have substantial missing data. We make use of recent advances in MODIS satellite data processing algorithms (Multi-Angle Implementation of Atmospheric Correction (MAIAC), which allow us to use 1 km (versus currently available 10 km) resolution AOD data.We developed and cross validated models to predict daily PM(sub 2.5) at a 1X 1 km resolution across the northeastern USA (New England, New York and New Jersey) for the years 2003-2011, allowing us to better differentiate daily and long term exposure between urban, suburban, and rural areas. Additionally, we developed an approach that allows us to generate daily high-resolution 200 m localized predictions representing deviations from the area 1 X 1 km grid predictions. We used mixed models regressing PM(sub 2.5) measurements against day-specific random intercepts, and fixed and random AOD and temperature slopes. We then use generalized additive mixed models with spatial smoothing to generate grid cell predictions when AOD was missing. Finally, to get 200 m localized predictions, we regressed the residuals from the final model for each monitor against the local spatial and temporal variables at each monitoring site. Our model performance was excellent (mean out-of-sample R(sup 2) = 0.88). The spatial and temporal components of the out-of-sample results also presented very good fits to the withheld data (R(sup 2) = 0.87, R(sup)2 = 0.87). In addition, our results revealed very little bias in the predicted concentrations (Slope of predictions versus withheld observations = 0.99). Our daily model results show high predictive accuracy at high spatial resolutions

  4. Correlation of lung abnormalities on high-resolution CT with clinical graft-versus-host disease after allogeneic versus autologous bone marrow transplantation in children

    Energy Technology Data Exchange (ETDEWEB)

    Merlini, Laura; Borzani, Irene Maria Olivia; Anooshiravani, Mehrak; Hanquinet, Sylviane [University of Geneva Children' s Hospital, Paediatric Radiology Unit, Geneva (Switzerland); Rochat, Isabelle [University of Geneva Children' s Hospital, Paediatric Pneumology Unit, Geneva (Switzerland); Ozsahin, Ayse Hulya [University of Geneva Children' s Hospital, Paediatric Oncology Unit, Geneva (Switzerland)

    2008-11-15

    Late-onset noninfectious pulmonary complications (LONIPCs) are life-threatening complications of bone marrow transplantation (BMT). Several pathological patterns are described in the literature with different prognoses, and with different relationships to graft-versus-host disease (GVHD). The role of high-resolution CT (HRCT) is not yet well established. To illustrate different patterns of LONIPCs on HRCT in allogeneic versus autologous BMT in order to investigate the correlation with chronic GVHD (cGVHD). A total of 67 HRCT scans were performed in 24 patients with noninfectious pulmonary disease at least 3 months after BMT (16 allogeneic, 8 autologous). Abnormality patterns and extension on HRCT images were correlated with the clinical outcome and with the severity of cGVHD. Of 24 patients, 9 showed LONIPCs (1 autologous, 8 allogeneic). There was a significant association between abnormalities on HRCT and severe cGVHD (P = 0.038), with no specific pattern. Prognosis seemed to be related to the severity of cGVHD and not to the extent of abnormalities on HRCT. The significant association between abnormalities on HRCT and severe GVHD suggests that LONIPCs can be a pulmonary manifestation of the disease. HRCT is a useful tool when combined with clinical data. (orig.)

  5. Bilateral Non-Hodgkin’s Lymphoma of the Temporal Bone: A Rare and Unusual Presentation

    Directory of Open Access Journals (Sweden)

    Sanjay Vaid

    2016-01-01

    Full Text Available Primary lymphoma of the temporal bone is an unusual finding in clinical practice and bilateral affection is even more rare. To the best of our knowledge, there are no reports of bilateral primary temporal bone lymphoma without middle ear involvement in the English medical literature so far. We report, for the first time, a case of primary lymphoma involving both temporal bones which presented with left-sided infranuclear facial palsy. A combination of contrast enhanced magnetic resonance imaging (MRI and high resolution computed tomography (HRCT was used to characterize and to map the extent of the lesion, as well as to identify the exact site of facial nerve affection. An excision biopsy and immunohistochemistry revealed diffuse large B-cell non-Hodgkin’s lymphoma (DLBCL. Whole body fluorodeoxyglucose (FDG positron emission tomography-computed tomography study (PET-CT was performed to stage the disease. The patient was treated with chemotherapy and radiation therapy and is now on regular follow-up. The patient is alive and asymptomatic without disease progression for the last twenty months after initial diagnosis.

  6. Assessment of bone microarchitecture in chronic kidney disease: a comparison of 2D bone texture analysis and high-resolution peripheral quantitative computed tomography at the radius and tibia.

    Science.gov (United States)

    Bacchetta, Justine; Boutroy, Stéphanie; Vilayphiou, Nicolas; Fouque-Aubert, Anne; Delmas, Pierre D; Lespessailles, Eric; Fouque, Denis; Chapurlat, Roland

    2010-11-01

    Bone microarchitecture can be studied noninvasively using high-resolution peripheral quantitative computed tomography (HR-pQCT). However, this technique is not widely available, so more simple techniques may be useful. BMA is a new 2D high-resolution digital X-ray device, allowing for bone texture analysis with a fractal parameter (H(mean)). The aims of this study were (1) to evaluate the reproducibility of BMA at two novel sites (radius and tibia) in addition to the conventional site (calcaneus), (2) to compare the results obtained with BMA at all of those sites, and (3) to study the relationship between H(mean) and trabecular microarchitecture measured with an in vivo 3D device (HR-pQCT) at the distal tibia and radius. BMA measurements were performed at three sites (calcaneus, distal tibia, and radius) in 14 healthy volunteers to measure the short-term reproducibility and in a group of 77 patients with chronic kidney disease to compare BMA results to HR-pQCT results. The coefficient of variation of H(mean) was 1.2, 2.1, and 4.7% at the calcaneus, radius, and tibia, respectively. We found significant associations between trabecular volumetric bone mineral density and microarchitectural variables measured by HR-pQCT and H(mean) at the three sites (e.g., Pearson correlation between radial trabecular number and radial H(mean) r = 0.472, P technique with few technical constraints. Thus, it may represent an interesting tool for evaluating bone structure, in association with biological parameters and DXA.

  7. Chondromyxoid fibroma of the temporal bone: CT and MRI findings

    Energy Technology Data Exchange (ETDEWEB)

    Tarhan, N.C.; Yologlu, Z.; Tutar, N.U.; Coskun, M.; Agildere, A.M. [Baskent Univ. School of Medicine, Bahcelievler Ankara (Turkey). Dept. of Radiology; Arikan, U. [Baskent Univ. School of Medicine, Bahcelievler Ankara (Turkey). Dept. of Pathology

    2000-10-01

    We present the case of a 44-year-old woman with chondromyxoid fibroma of temporal bone origin. Since this is the least common bone tumor of cartilaginous origin, it is highly unusual to find this tumor in the skull. In fact, the literature describes 18 cases of this form of neoplasia arising in the skull, only 4 of these having originated in the temporal bone. To date, the radiological features of these tumors, and especially features detected using the latest imaging modalities, have not been described in detail. This report is unique in that it is the first to present a case of chondromyxoid fibroma of the temporal bone accompanied by detailed CT and MRI findings. (orig.)

  8. A randomized double-blind placebo-controlled trial to investigate the effects of nasal calcitonin on bone microarchitecture measured by high-resolution peripheral quantitative computerized tomography in postmenopausal women — Study protocol

    Directory of Open Access Journals (Sweden)

    Azria Moise

    2008-04-01

    Full Text Available Abstract Background Bone microarchitecture is a significant determinant of bone strength. So far, the assessment of bone microarchitecture has required bone biopsies, limiting its utilization in clinical practice to one single skeletal site. With the advance of high-resolution imaging techniques, non-invasive in vivo measurement of bone microarchitecture has recently become possible. This provides an opportunity to efficiently assess the effects of anti-osteoporotic therapies on bone microarchitecture. We therefore designed a protocol to investigate the effects of nasal salmon calcitonin, an inhibitor of osteoclast activity, on bone microarchitecture in postmenopausal women, comparing weight bearing and non-weight bearing skeletal sites. Methods One hundred postmenopausal women will be included in a randomized, placebo-controlled, double-blind trial comparing the effect of nasal salmon calcitonin (200 UI/day to placebo over two years. Bone microarchitecture at the distal radius and distal tibia will be determined yearly by high-resolution peripheral quantitative computerized tomography (p-QCT with a voxel size of 82 μm and an irradiation of less than 5 μSv. Serum markers of bone resorption and bone formation will be measured every 6 months. Safety and compliance will be assessed. Primary endpoint is the change in bone microarchitecture; secondary endpoint is the change in markers of bone turnover. Hypothesis The present study should provide new information on the mode of action of nasal calcitonin. We hypothezise that - compared to placebo - calcitonin impacts on microstructural parameters, with a possible difference between weight bearing and non-weight bearing bones. Trial Registration ClinicalTrials.gov NCT00372099

  9. CT-MR image data fusion for computer assisted navigated neurosurgery of temporal bone tumors

    Energy Technology Data Exchange (ETDEWEB)

    Nemec, Stefan Franz [Department of Radiology/Osteology, Medical University Vienna, Waehringerguertel 18-20, A-1090 Vienna (Austria)]. E-mail: stefan.nemec@meduniwien.ac.at; Donat, Markus Alexander [Department of Neurosurgery, Medical University Vienna, Waehringerguertel 18-20, A-1090 Vienna (Austria); Mehrain, Sheida [Department of Radiology/Osteology, Medical University Vienna, Waehringerguertel 18-20, A-1090 Vienna (Austria); Friedrich, Klaus [Department of Radiology/Osteology, Medical University Vienna, Waehringerguertel 18-20, A-1090 Vienna (Austria); Krestan, Christian [Department of Radiology/Osteology, Medical University Vienna, Waehringerguertel 18-20, A-1090 Vienna (Austria); Matula, Christian [Department of Neurosurgery, Medical University Vienna, Waehringerguertel 18-20, A-1090 Vienna (Austria); Imhof, Herwig [Department of Radiology/Osteology, Medical University Vienna, Waehringerguertel 18-20, A-1090 Vienna (Austria); Czerny, Christian [Department of Radiology/Osteology, Medical University Vienna, Waehringerguertel 18-20, A-1090 Vienna (Austria)

    2007-05-15

    Purpose: To demonstrate the value of multi detector computed tomography (MDCT) and magnetic resonance imaging (MRI) in the preoperative work up of temporal bone tumors and to present, especially, CT and MR image fusion for surgical planning and performance in computer assisted navigated neurosurgery of temporal bone tumors. Materials and methods: Fifteen patients with temporal bone tumors underwent MDCT and MRI. MDCT was performed in high-resolution bone window level setting in axial plane. The reconstructed MDCT slice thickness was 0.8 mm. MRI was performed in axial and coronal plane with T2-weighted fast spin-echo (FSE) sequences, un-enhanced and contrast-enhanced T1-weighted spin-echo (SE) sequences, and coronal T1-weighted SE sequences with fat suppression and with 3D T1-weighted gradient-echo (GE) contrast-enhanced sequences in axial plane. The 3D T1-weighted GE sequence had a slice thickness of 1 mm. Image data sets of CT and 3D T1-weighted GE sequences were merged utilizing a workstation to create CT-MR fusion images. MDCT and MR images were separately used to depict and characterize lesions. The fusion images were utilized for interventional planning and intraoperative image guidance. The intraoperative accuracy of the navigation unit was measured, defined as the deviation between the same landmark in the navigation image and the patient. Results: Tumorous lesions of bone and soft tissue were well delineated and characterized by CT and MR images. The images played a crucial role in the differentiation of benign and malignant pathologies, which consisted of 13 benign and 2 malignant tumors. The CT-MR fusion images supported the surgeon in preoperative planning and improved surgical performance. The mean intraoperative accuracy of the navigation system was 1.25 mm. Conclusion: CT and MRI are essential in the preoperative work up of temporal bone tumors. CT-MR image data fusion presents an accurate tool for planning the correct surgical procedure and is a

  10. Study of the feasible size of a bone conduction implant transducer in the temporal bone.

    Science.gov (United States)

    Reinfeldt, Sabine; Östli, Per; Håkansson, Bo; Taghavi, Hamidreza; Eeg-Olofsson, Måns; Stalfors, Joacim

    2015-04-01

    The aim was to assess the temporal bone volume to determine the suitable size and position of a bone conduction implant (BCI) transducer. A BCI transducer needs to be sufficiently small to fit in the mastoid portion of the temporal bone for a majority of patients. The anatomical geometry limits both the dimension of an implanted transducer and its positions in the temporal bone to provide a safe and simple surgery. Computed tomography (CT) scans of temporal bones from 22 subjects were virtually reconstructed. With an algorithm in MATLAB, the maximum transducer diameter as function of the maximum transducer depth in the temporal bone, and the most suitable position were calculated in all subjects. An implanted transducer diameter of 16 mm inserted at a depth of 4 mm statistically fitted 95% of the subjects. If changing the transducer diameter to 12 mm, a depth of 6 mm would fit in 95% of the subjects. The most suitable position was found to be around 20 mm behind the ear canal. The present BCI transducer casing, used in ongoing clinical trials, was designed from the results in this study, demonstrating that the present BCI transducer casing (largest diameter [diagonal]: 15.5 mm, height: 6.4 mm) will statistically fit more than 95% of the subjects. Hence, the present BCI transducer is concluded to be sufficiently small to fit most normal-sized temporal bones and should be placed approximately 20 mm behind the ear canal.

  11. Contralateral Cochlear Labyrinthine Concussion without Temporal Bone Fracture: Unusual Posttraumatic Consequence

    Science.gov (United States)

    Méndez, D.; Silva, J. M. Duque; del Álamo, P. Ortega

    2016-01-01

    Introduction. Labyrinthine concussion is a term used to describe a rare cause of sensorineural hearing loss with or without vestibular symptoms occurring after head trauma. Isolated damage to the inner ear without involving the vestibular organ would be designated as a cochlear labyrinthine concussion. Hearing loss is not a rare finding in head trauma that involves petrous bone fractures. Nevertheless it generally occurs ipsilateral to the side of the head injury and extraordinarily in the contralateral side and moreover without the presence of a fracture. Case Report. The present case describes a 37-year-old patient with sensorineural hearing loss and tinnitus in his right ear after a blunt head trauma of the left-sided temporal bone (contralateral). Otoscopy and radiological images showed no fractures or any abnormalities. A severe sensorineural hearing loss was found in his right ear with a normal hearing of the left side. Conclusion. The temporal bone trauma requires a complete diagnostic battery which includes a neurotologic examination and a high resolution computed tomography scan in the first place. Hearing loss after a head injury extraordinarily occurs in the contralateral side of the trauma as what happened in our case. In addition, the absence of fractures makes this phenomenon even more unusual.

  12. Myxoma of the temporal bone: A rare neoplasm

    Directory of Open Access Journals (Sweden)

    Kapil Sikka

    2011-01-01

    Full Text Available Myxomas of the temporal bone are rare mesenchymal tumors. We present a case of a 16-year-old girl who presented with complaint of mass lesion protruding from the right ear canal and from behind the ear for last 2 years. Biopsy of the mass was suggestive of benign mesenchymal lesion with prominent myxoid changes. Radiology of the temporal bone showed soft tissue density involving right side external auditory canal, middle ear, mastoid antrum and both lobes of the parotid gland. Tumour excision along with total parotidectomy was performed. Postoperative histopatholgy was consistent with myxoma. The patient is on regular follow-up for last 5months with no recurrence till date. Temporal bone myxomas are rare neoplasms which are surgically treatable but have a strong tendency to recur, necessiating long-term follow-up.

  13. Massive Cerebrospinal Fluid Leak of the Temporal Bone

    Directory of Open Access Journals (Sweden)

    Giannicola Iannella

    2016-01-01

    Full Text Available Cerebrospinal fluid (CSF leakage of the temporal bone region is defined as abnormal communications between the subarachnoidal space and the air-containing spaces of the temporal bone. CSF leak remains one of the most frequent complications after VS surgery. Radiotherapy is considered a predisposing factor for development of temporal bone CSF leak because it may impair dural repair mechanisms, thus causing inadequate dural sealing. The authors describe the case of a 47-year-old man with a massive effusion of CSF which extended from the posterior and lateral skull base to the first cervical vertebrae; this complication appeared after a partial enucleation of a vestibular schwannoma (VS with subsequent radiation treatment and second operation with total VS resection.

  14. Characteristics of osteoma of the temporal bone in young adolescents.

    Science.gov (United States)

    Viswanatha, Borlingegowda

    2011-02-01

    The author conducted a retrospective review of the clinical presentation, management, and complications of temporal bone osteoma in young adolescents. The study population was made up of 9 patients-5 girls and 4 boys, aged 12 to 15 years at presentation (mean: 13.7)-who had been seen for radiologically and histopathologically proven temporal bone osteoma at the author's institution over a 9-year period. Of this group, 5 patients had extracanalicular osteoma (3 in the mastoid portion of the temporal bone, 1 in the squamous portion, and 1 in the mastoid antrum) and 4 patients had osteoma of the external auditory canal. Six of the 9 patients underwent surgical treatment; of the remainder, 1 refused surgery and 2 were managed conservatively with ongoing observation. All patients were followed for a minimum of 1 year, and no recurrences and no complications were observed during that time.

  15. High Resolution Elevation Contours

    Data.gov (United States)

    Minnesota Department of Natural Resources — This dataset contains contours generated from high resolution data sources such as LiDAR. Generally speaking this data is 2 foot or less contour interval.

  16. Diagnosis of ossicular deformities and inner ear anomalies by high resolution CT scanning of the temporal bone

    Energy Technology Data Exchange (ETDEWEB)

    Isono, Michio

    1988-04-01

    A comparative study was undertaken to determine the optimum slice thickness and slice gaps that can define the fine contour and continuity of the ossicles and the inner ear. Horizontal tomography was proved to be contributory enough to obtain the whole ossicular chains and the whole labyrinthine capsule. Comparison of 1.5 mm slice thickness / 1.5 mm slice gaps, 1.0 mm slice thickness / 1.0 mm slice gaps and 1.5 mm slice thickness / 1.0 mm slice gaps revealed that the last condition was optimal for demonstrating the ossicular chains, the first for the inner ear. A significant relationship was found between CT findings and surgical findings of ossicular chains in chronic otitis media and cholesteatoma. Radiological classification of the inner ear malformation, which was obtained by this method, were agenesis of the whole labyrinthine capsule, agenesis of the cochlea, slight protrusion of the cochlear growth, poor cochlear turning, agenesis of all the semicircular canals, anterior semicircular canals (s.c.) without posterior and lateral s.c., anterior s.c. without hypoplasia of posterior s.c. and aplasia of lateral s.c., and smallness of the vestibule. (author) 59 refs.

  17. Craniofacial and temporal bone CT findings in cleidocranial dysplasia

    Energy Technology Data Exchange (ETDEWEB)

    Gonzalez, Guido E. [Massachusetts General Hospital and Harvard Medical School, Department of Radiology, Boston, MA (United States); Clinica Alemana de Santiago, Departamento de Imagenes, Santiago (Chile); Caruso, Paul A.; Curtin, Hugh D. [Massachusetts Eye and Ear Infirmary and Harvard Medical School, Department of Radiology, Boston, MA (United States); Small, Juan E. [Massachusetts General Hospital and Harvard Medical School, Department of Radiology, Boston, MA (United States); Massachusetts Eye and Ear Infirmary and Harvard Medical School, Department of Radiology, Boston, MA (United States); Jyung, Robert W. [Massachusetts Eye and Ear Infirmary and Harvard Medical School, Department of Otology, Boston, MA (United States); Troulis, Maria J. [Massachusetts General Hospital and Harvard Medical School, Department of Oral and Maxillofacial Surgery, Boston, MA (United States)

    2008-08-15

    Cleidocranial dysplasia (CCD) is a multistructural polyostotic genetic disorder that results from mutation of the CBFA1 gene. Hearing loss is a frequent finding in CCD. We describe the CT craniofacial findings in CCD and provide a comprehensive discussion of the CT temporal bone findings in these patients. (orig.)

  18. Good experiences with interactive temporal bone surgical simulator

    DEFF Research Database (Denmark)

    Andersen, Steven A W; Mikkelsen, Peter Trier; Noe, Karsten Ostergaard;

    2014-01-01

    The Visible Ear Simulator (VES) is a freeware temporal bone surgical simulator utilizing a high-fidelity haptic and graphical voxel model compiled from segmented digital images of fresh frozen sections. A haptic device provides the 3-dimensional handling and drilling with force-feedback in real...

  19. Temporal bone verrucous carcinoma: outcomes and treatment controversy

    Science.gov (United States)

    Martin, Neil; Juillard, Guy F.; Bhuta, Sunita; Ishiyama, Akira

    2010-01-01

    Verrucous carcinoma is a rare tumor that presents in the head and neck with the most common sites being the oral cavity and larynx. Fourteen cases of verrucous carcinoma of the temporal bone have been described in literature; this study aims to examine treatment outcomes and discuss the controversy surrounding postoperative radiation. The study design included a literature review along with individual case report in the setting of a tertiary care medical center. Outcome analysis of all cases of verrucous carcinoma of the temporal bone, which are documented in the English literature, and presentation of a single patient report including gross, histologic and radiologic analyses were performed. The longest recorded survival for verrucous carcinoma of the temporal bone occurs in patients treated with surgery alone. Poorer outcomes for patients treated with adjuvant (chemo)radiation may be due to more advanced stage of disease at the time of treatment. Early reports of radiation leading to tumor dedifferentiation or early recurrence are not supported by more recent studies. Whether adjuvant radiation therapy is indicated in verrucous carcinoma of the temporal bone remains controversial. PMID:20502907

  20. Langerhans cell histiocytosis of the temporal bone in a child

    Directory of Open Access Journals (Sweden)

    A Chakravarti

    2011-12-01

    Full Text Available Langerhans cell histiocytosis of temporal bone is a benign tumor like condition with variable clinical course. This rare clinical entity may mimic common ENT clinical condition like otitis media , mastoiditis and otitis externa . A high index of suspicion is required to reach to a diagnosis of langerhans cell histiocytosis to prevent delay in proper management of this disease.

  1. High-resolution computed tomography findings in pulmonary complications after bone marrow transplantation: iconographic essay; Tomografia computadorizada de alta resolucao nas complicacoes pulmonares pos-transplante de medula ossea: ensaio iconografico

    Energy Technology Data Exchange (ETDEWEB)

    Gasparetto, Emerson L.; Ono, Sergio E.; Souza, Carolina A. [Parana Univ., Curitiba, PR (Brazil). Hospital de Clinicas. Servico de Radiologia Medica e Diagnostico por Imagem]. E-mail: gasparetto@hotmail.com; Escuissato, Dante L. [Parana Univ., Curitiba, PR (Brazil). Faculdade de Medicina. Disciplina de Radiologia Medica; Rocha, Gabriela de Melo; Inoue, Cezar; Falavigna, Joao M. [Parana Univ., Curitiba, PR (Brazil). Faculdade de Medicina; Marchiori, Edson [Universidade Federal Fluminense (UFF), Niteroi, RJ (Brazil). Faculdade de Medicina. Dept. de Radiologia; Universidade Federal, Rio de Janeiro (UFRJ), RJ (Brazil). Curso de Pos-graduacao em Radiologia

    2005-12-01

    Bone marrow transplantation has been the treatment of choice for many hematologic diseases. However, pulmonary complications, which may occur in up to 60% of the patients, are the main cause of treatment failure and may be divided in three phases according to the patient's immunity. In the first phase, up to 30 days after the procedure, there is a predominance of non-infectious complications and fungal pneumonia. Viral infections, mainly by cytomegalovirus, are common in the second phase (up to 100 days after bone marrow transplantation). Finally, in the late phase after bone marrow transplantation, non-infectious complications as bronchiolitis obliterans organizing pneumonia and graft-versus-host disease are most commonly seen. The authors present a pictorial essay of the high-resolution computed tomography findings in patients with pulmonary complications after bone marrow transplantation. (author)

  2. Multimodal imaging of the human temporal bone: A comparison of CT and optical scanning techniques

    Science.gov (United States)

    Voie, Arne H.; Whiting, Bruce; Skinner, Margaret; Neely, J. Gail; Lee, Kenneth; Holden, Tim; Brunsden, Barry

    2003-10-01

    A collaborative effort between Washington University in St. Louis and Spencer Technologies in Seattle, WA has been undertaken to create a multimodal 3D reconstruction of the human cochlea and vestibular system. The goal of this project is to improve the accuracy of in vivo CT reconstructions of implanted cochleae, and to expand the knowledge of high-resolution anatomical detail provided by orthogonal-plane optical sectioning (OPFOS). At WUSL, computed tomography (CT) images of the cochlea are used to determine the position of cochlear implant electrodes relative to target auditory neurons. The cochlear implant position is determined using pre- and post-operative CT scans. The CT volumes are cross-registered to align the semicircular canals and internal auditory canal, which have a unique configuration in 3-D space. The head of a human body donor was scanned with a clinical CT device, after which the temporal bones were removed, fixed in formalin and trimmed prior to scanning with a laboratory Micro CT scanner. Following CT, the temporal bones were sent to the OPFOS Imaging Lab at Spencer Technologies for a further analysis. 3-D reconstructions of CT and OPFOS imaging modalities were compared, and results are presented. [Work supported by NIDCD Grants R44-03623-5 and R01-00581-13.

  3. Post-Traumatic Bilateral Facial Paralysis Associated with Temporal Bone Fracture.

    Science.gov (United States)

    Habib, Syed Shahid; Al Rouq, Fawzia; Meo, Imran

    2015-10-01

    Bilateral traumatic facial paralysis is a very rare clinical condition. Loss of taste sensation, associated with bilateral traumatic paralysis, is even rarer and has not been well described in the literature. In this report, a 23-year old male, who developed bilateral facial paralysis with loss of taste sensation and hearing impairment, following a motor vehicle accident, is presented. He had initially presented with unconsciousness for about 2 hours after he sustained closed head injury after a motor vehicle accident. Initial Computed Tomography (CT) scans revealed a small epidural hematoma, right temporal bone fracture and air densities around the basal cistern. On the 4th day after trauma, he was noted to have incomplete closure of both eyes and was feeling difficulty with chewing and drooling of saliva. Electrodiagnostic testing confirmed the diagnosis of bilateral facial paralysis-House-Brackmann (HB) grade V. Electroneuronography (ENoG) showed degeneration of 90% nerve fibres bilaterally. The high-resolution CT scans showed bilateral temporal bone fractures. At 3 months of follow-up, the patient had partial recovery of facial nerve function bilaterally and improvement in HB classification to grade III and ENoG of 60% was observed.

  4. Aspects of temporal bone anatomy and pathology in conjunction with cochlear implant surgery

    Energy Technology Data Exchange (ETDEWEB)

    Stjernholm, Christina [Karolinska Inst., Stockholm (Sweden). Soedersjukhuset

    2003-07-01

    Cochlear implantation is a treatment for patients with severe sensorineural hearing loss/deafness, who get no help from ordinary hearing aids. The cochlear implant is surgically placed under the skin near the ear and a very thin electrode array is introduced into the cochlea of the inner ear, where it stimulates the remaining nerve fibers. The operation is complicated; it is performed with the aid of a microscope, and involves drilling very close to vital vessels and important nerves. High resolution computed tomography (CT) of the temporal bone is a part of the preoperative evaluation preceding cochlear implantation. It is a method for visualizing the bony structures of the middle and inner ear - to diagnose pathology and to describe the anatomy. The first work concerns CT of the temporal bone and cochlear implant surgery in children with CHARGE association. This is a rare condition with multiple congenital abnormalities, sometimes lethal. Children with CHARGE have different combinations of disabilities, of which impairments of vision and hearing, as well as balance problems and facial palsy can lead to developmental delay. There have been few reports of radiological temporal bone changes and none of cochlear implant surgery for this group. The work includes a report of the findings on preoperative CT and at surgery, as well as postimplant results in two children. A review of the latest diagnostic criteria of CHARGE and the temporal bone changes found in international literature is also included. The conclusion was that certain combinations of temporal bone changes in CHARGE are, if not specific, at least extremely rare in other materials. CT can visualize these changes and be used as a diagnostic tool. This is important, since some of the associated disabilities are not so obvious from the start. Early treatment is vital for the child's development. This work also shows that cochlear implantation may help some of these often very isolated children to

  5. Temporal bone characterization and cochlear implant feasibility in the common marmoset (Callithrix jacchus).

    Science.gov (United States)

    Johnson, Luke A; Della Santina, Charles C; Wang, Xiaoqin

    2012-08-01

    The marmoset (Callithrix jacchus) is a valuable non-human primate model for studying behavioral and neural mechanisms related to vocal communication. It is also well suited for investigating neural mechanisms related to cochlear implants. The purpose of this study was to characterize marmoset temporal bone anatomy and investigate the feasibility of implanting a multi-channel intracochlear electrode into the marmoset scala tympani. Micro computed tomography (microCT) was used to create high-resolution images of marmoset temporal bones. Cochlear fluid spaces, middle ear ossicles, semicircular canals and the surrounding temporal bone were reconstructed in three-dimensional space. Our results show that the marmoset cochlea is ∼16.5 mm in length and has ∼2.8 turns. The cross-sectional area of the scala tympani is greatest (∼0.8 mm(2)) at ∼1.75 mm from the base of the scala, reduces to ∼0.4 mm(2) at 5 mm from the base, and decreases at a constant rate for the remaining length. Interestingly, this length-area profile, when scaled 2.5 times, is similar to the scala tympani of the human cochlea. Given these dimensions, a compatible multi-channel implant electrode was identified. In a cadaveric specimen, this electrode was inserted ¾ turn into the scala tympani through a cochleostomy at ∼1 mm apical to the round window. The depth of the most apical electrode band was ∼8 mm. Our study provides detailed structural anatomy data for the middle and inner ear of the marmoset, and suggests the potential of the marmoset as a new non-human primate model for cochlear implant research.

  6. High-resolution headlamp

    Science.gov (United States)

    Gut, Carsten; Cristea, Iulia; Neumann, Cornelius

    2016-04-01

    The following article shall describe how human vision by night can be influenced. At first, front lighting systems that are already available on the market will be described, followed by their analysis with respect to the positive effects on traffic safety. Furthermore, how traffic safety by night can be increased since the introduction of high resolution headlamps shall be discussed.

  7. Temporal bone trauma and imaging; Schlaefenbeintrauma und Bildgebung

    Energy Technology Data Exchange (ETDEWEB)

    Turetschek, K.; Czerny, C.; Wunderbaldinger, P. [Universitaetsklinik fuer Radiodiagnostik, AKH Wien (Austria); Steiner, E. [Inst. fuer Digitale Bilddiagnostik, St. Poelten (Austria)

    1997-12-01

    Fractures of the temporal bone result from direct trauma to the temporal bone or occur as one component of a severe craniocerebral injury. Complications of temporal trauma are hemotympanon, facial nerve paralysis, conductive or sensorineur hearing loss, and leakage of cerebrospinal fluid. Erly recognition and an appropiate therapy may improve or prevent permanent deficits related to such complications. Only 20-30% of temporal bone fractures can be visualized by plain films. CT has displaced plain radiography in the investigation of the otological trauma because subtle bony details are best evaluated by CT which even can be reformatted in multiple projections, regardless of the original plane of scanning. Associated epidural, subdural, and intracerebral hemorrhagic lesions are better defined by MRI. (orig.) [Deutsch] Frakturen des Schlaefenbeins koennen entweder isoliert oder im Rahmen eines schweren Schaedel-/Hirntraumas auftreten. Die haeufigsten Komplikationen dieser Traumen sind Haematotympanon, Fazialisparese, Hoerverlust und eine Liquorfistel. Die prompte und rasche Diagnose dieser Komplikationen sowie eine gezielte Therapie koennen Spaetfolgen (v.a. Hoer- und/oder Gleichgewichtsverlust) verhindern. Auf konventionellen Roentgenaufnahmen koennen nur 20-30% aller Schlaefenbeinfrakturen nachgewiesen werden. Somit ist die Computertomographie bei diesen Patienten heute die Methode der Wahl, da selbst subtile knoecherne Details noch in hervorragender Aufloesung dargestellt werden. Begleitende intrakranielle Komplikationen (epi-/subdurale oder auch intrazerebrale Loesionen) sind mittels Magnetresonanztomographie besser nachweisbar. (orig.)

  8. Osteoradionecrosis of the Temporal Bone Leading to Cerebellar Abscess.

    Science.gov (United States)

    Layton, Thomas B

    2017-01-01

    Squamous cell carcinoma of the temporal bone is a rare and destructive malignancy and represents both diagnostic and therapeutic challenge. The complex regional anatomy of the temporal bone requires equally intricate surgical techniques to adequately resect the tumour mass during surgical excision. Adjuvant radiotherapy is offered to patients with advanced disease and has been showed to confer a survival benefit in carefully selected patients. One feared complication of radiotherapy is osteoradionecrosis and is a major obstacle faced in the treatment of head and neck cancers. The case presented here is a rare example of a patient who was successfully treated for SCC of the temporal with both surgical resection and adjuvant radiotherapy who subsequently developed two major complications: first, osteoradionecrosis of the temporal bone that leads to penetrating osteomyelitis; second, the formation of a large cerebellar abscess that required surgical drainage. This case is a rare example of the complications that are possible following radiotherapy to the head and the close follow-up that is required in patients.

  9. CT findings of the temporal bone in CHARGE syndrome : aspects of importance in cochlear implant surgery

    NARCIS (Netherlands)

    Vesseur, A. C.; Verbist, B. M.; Westerlaan, H. E.; Kloostra, F. J. J.; Admiraal, R. J. C.; van Ravenswaaij-Arts, C. M. A.; Free, R. H.; Mylanus, E. A. M.

    2016-01-01

    To provide an overview of anomalies of the temporal bone in CHARGE syndrome relevant to cochlear implantation (CI), anatomical structures of the temporal bone and the respective genotypes were analysed. In this retrospective study, 42 CTs of the temporal bone of 42 patients with CHARGE syndrome were

  10. Temporal bone trauma and complications: computed tomography findings

    Energy Technology Data Exchange (ETDEWEB)

    Costa, Ana Maria Doffemond; Gaiotti, Juliana Oggioni; Couto, Caroline Laurita Batista; Gomes, Natalia Delage; Diniz, Renata Lopes Furletti Caldeira; Motta, Emilia Guerra Pinto Coelho, E-mail: anadoffemond@yahoo.com.br [Hospital Mater Dei, Belo Horizonte, MG (Brazil). Unit of Radiology and Imaging Diagnosis

    2013-03-15

    Most temporal bone fractures result from high-energy blunt head trauma, and are frequently related to other skull fractures or to polytrauma. Fractures and displacements of ossicular chain in the middle ear represent some of the main complications of temporal bone injury, and hence they will be more deeply approached in the present article. Other types of injuries include labyrinthine fractures, dural fistula, facial nerve paralysis and extension into the carotid canal. Computed tomography plays a fundamental role in the initial evaluation of polytrauma patients, as it can help to identify important structural injuries that may lead to severe complications such as sensorineural hearing loss, conductive hearing loss, dizziness and balance dysfunction, perilymphatic fistulas, facial nerve paralysis, vascular injury and others. (author)

  11. Ultra high resolution tomography

    Energy Technology Data Exchange (ETDEWEB)

    Haddad, W.S.

    1994-11-15

    Recent work and results on ultra high resolution three dimensional imaging with soft x-rays will be presented. This work is aimed at determining microscopic three dimensional structure of biological and material specimens. Three dimensional reconstructed images of a microscopic test object will be presented; the reconstruction has a resolution on the order of 1000 A in all three dimensions. Preliminary work with biological samples will also be shown, and the experimental and numerical methods used will be discussed.

  12. High Resolution Acoustical Imaging

    Science.gov (United States)

    1989-05-01

    1028 (September 1982). 26 G. Arfken , Mathematical Methods for Physicists (Academic Press, New York, 1971), 2nd printing, pp.662-666. 27 W. R. Hahn...difference in the approach used by the two methods , as noted in the previous paragraph, forming a direct mathematical com- parison may be impossible...examines high resolution methods which use a linear array to locate stationary objects which have scattered the fressure waves. Several;- new methods

  13. A metastatic glomus jugulare tumor. A temporal bone report

    Energy Technology Data Exchange (ETDEWEB)

    El Fiky, F.M.; Paparella, M.M.

    1984-01-01

    The clinicopathologic findings in the temporal bone of a patient with a highly malignant metastasizing glomus jugulare tumor are reported. The patient exhibited all the symptoms of primary malignant tumors of the ear, including facial paralysis, otorrhea, pain, hearing loss, tinnitus, dizziness, and vertigo. He was treated with cobalt irradiation followed by radium implant in the ear canal for a residual tumor; then a left-sided radical mastoidectomy was performed.

  14. Bone geometry, density, and microarchitecture in the distal radius and tibia in adults with osteogenesis imperfecta type I assessed by high-resolution pQCT

    DEFF Research Database (Denmark)

    Folkestad, Lars; Hald, Jannie Dahl; Hansen, Stinus

    2012-01-01

    Osteogenesis Imperfecta (OI) is a hereditary disorder characterized by decreased biosynthesis or impaired morphology of collagen type-1 that leads to decreased bone mass and increased bone fragility. We hypothesized that patients with OI have altered bone microstructure and bone geometry. In this...... treated with bisphosphonates. HR-pQCT at the distal radius and distal tibia and dual-energy X-ray absorptiomentry of total hip, femoral neck, trochanteric region and the lumbar spine (L1-L4) were performed. The patients were shorter than the controls (159¿±¿10¿cm vs. 170¿±¿9¿cm, p¿...

  15. High resolution three-dimensional (256 to the 3rd) spatio-temporal measurements of the conserved scalar field in turbulent shear flows

    Science.gov (United States)

    Dahm, Werner J. A.; Buch, Kenneth A.

    Results from highly resolved three-dimensional spatio-temporal measurements of the conserved scalar field zeta(x,t) in a turbulent shear flow. Each of these experiments consists of 256 to the 3rd individual point measurements of the local instantaneous conserved scalar value in the flow. The spatial and temporal resolution of these measurements reach beyond the local Kolmogorov scale and resolve the local strain-limited molecular diffusion scale in the flow. The results clearly show molecular mixing occurring in thin strained laminar diffusion layers in a turbulent flow.

  16. MR and CT findings of temporal bone langerhans cell histiocytosis

    Energy Technology Data Exchange (ETDEWEB)

    Bae, Jae Ig; Lee, Hee Jung; Kim, Heung Sik [Keimyung Univ. School of Medicine, Dongsan Medical Center, Taegu (Korea, Republic of)

    2001-11-01

    To describe the MRI and CT findings of temperal bone langerhans cell histiocytosis. The MRI (n=8) and CT (n=7) findings of nine lesions of temporal bone Langerhans cell histiocytosis in six children were retrospectively reviewed. Eight lesions were pathologically confirmed and one was clinically diagnosed. The findings were analyzed for bilaterality, location, lesion extent, signal intensity, the attenuation of soft tissue lesions seen at MRI or precontrast CT, enhancement pattern at MRI or CT, and the pattern of bony destruction at CT. Bilateral involvement was present in three of six patients (50%). Lesions were most frequently located in the mastoid (n=8, 89%), followed by the petrous ridge (n=6, 67%), and the squamous portion (n=3, 33%). Seven (78%) lesions extended to the ipsilateral cavernous sinus (n=3), sphenoid bone (n=3), orbit (n=2), or epidural space (n=2). The signals of the soft tissue lesions were isointense in five cases (63%) on T1-weighted images and hyperintense in six (75%) at MRI, and homogeneous in five (71%) at CT. All lesions demonstrated bony destruction without periosteal reaction and five (71%) showed ill-defined destruction, with crossing sutures. Familiarity with findings of predominant mastoid involvement, isointense or isodense soft tissue lesions seen on T1-weighted images or at precontrast CT, with relatively homogeneous enhancement at CT, and irregular bony destruction with crossing sutures may be helpful in narrowing the diagnosis of temporal bone langerhans cell histiocytosis.

  17. Using high-resolution soil moisture modelling to assess the uncertainty of microwave remotely sensed soil moisture products at the correct spatial and temporal support

    NARCIS (Netherlands)

    Wanders, N.; Karssenberg, D.; Bierkens, M. F. P.; Van Dam, J. C.; De Jong, S. M.

    2012-01-01

    Soil moisture is a key variable in the hydrological cycle and important in hydrological modelling. When assimilating soil moisture into flood forecasting models, the improvement of forecasting skills depends on the ability to accurately estimate the spatial and temporal patterns of soil moisture con

  18. Classification of temporal bone pneumatization based on sigmoid sinus using computed tomography

    Energy Technology Data Exchange (ETDEWEB)

    Han, S.-J. [Department of Otorhinolaryngology, National Health Insurance Corporation Ilsan Hospital, Seoul (Korea, Republic of); Song, M.H. [Department of Otorhinolaryngology, Yonsei University College of Medicine, Kang-nam Gu, Do-gok Dong, 146-92, Seoul, Republic of Korea 135-720 (Korea, Republic of); Kim, J. [Department of Radiology, Yonsei University College of Medicine, Seoul (Korea, Republic of); Lee, W.-S. [Department of Otorhinolaryngology, Yonsei University College of Medicine, Kang-nam Gu, Do-gok Dong, 146-92, Seoul, Republic of Korea 135-720 (Korea, Republic of); Lee, H.-K. [Department of Otorhinolaryngology, Yonsei University College of Medicine, Kang-nam Gu, Do-gok Dong, 146-92, Seoul, Republic of Korea 135-720 (Korea, Republic of)], E-mail: hoki@yuhs.ac

    2007-11-15

    Aim: To analyse several reference structures using axial computed tomography (CT) imaging of the temporal bone, which may reflect pneumatization of the entire temporal bone by statistical correlation to the actual volume of the temporal bone measured using three-dimensional reconstruction. Materials and methods: One hundred and sixteen temporal bones were studied, comprising 48 with normal findings and 68 sides showing chronic otitis media or temporal bone fracture. After measuring the volume of temporal bone air cells by the volume rendering technique using three-dimensional reconstruction images, classification of temporal bone pneumatization was performed using various reference structures on axial images to determine whether significant differences in the volume of temporal bone air cells could be found between the groups. Results: When the sigmoid sinus at the level of the malleoincudal complex was used in the classification, there were statistically significant differences between the groups that correlated with the entire volume of the temporal bone. Grouping based on the labyrinth and the ascending carotid artery showed insignificant differences in volume. Furthermore, there was no significant correlation between the cross-sectional area of the antrum and the entire volume of the temporal bone. Conclusion: The degree of pneumatization of temporal bone can be estimated easily by the evaluation of the air cells around the sigmoid sinus on axial CT images.

  19. Temporal bone chondroblastoma with secondary aneurysmal bone cyst presenting as an intracranial mass with clinical seizure activity.

    Science.gov (United States)

    Stapleton, Christopher J; Walcott, Brian P; Linskey, Katy R; Kahle, Kristopher T; Nahed, Brian V; Asaad, Wael F

    2011-06-01

    Chondroblastomas are rare tumors that characteristically arise from the epiphyseal cartilage of long bones of the immature skeleton. Intracranial involvement is uncommon, though the squamous portion of the temporal bone is preferentially affected due to its cartilaginous origin. Patients with temporal bone chondroblastomas classically present with otologic symptoms, while primary neurological complaints are rare. In this report, we describe a 33 year-old man with a chondroblastoma of the temporal bone and an associated aneurysmal bone cyst constituting a large intracranial mass lesion who presented with new-onset seizure activity. We review issues relevant to the pathology and treatment of these lesions.

  20. Use of Aerial high resolution visible imagery to produce large river bathymetry: a multi temporal and spatial study over the by-passed Upper Rhine

    Science.gov (United States)

    Béal, D.; Piégay, H.; Arnaud, F.; Rollet, A.; Schmitt, L.

    2011-12-01

    Aerial high resolution visible imagery allows producing large river bathymetry assuming that water depth is related to water colour (Beer-Bouguer-Lambert law). In this paper we aim at monitoring Rhine River geometry changes for a diachronic study as well as sediment transport after an artificial injection (25.000 m3 restoration operation). For that a consequent data base of ground measurements of river depth is used, built on 3 different sources: (i) differential GPS acquisitions, (ii) sounder data and (iii) lateral profiles realized by experts. Water depth is estimated using a multi linear regression over neo channels built on a principal component analysis over red, green and blue bands and previously cited depth data. The study site is a 12 km long reach of the by-passed section of the Rhine River that draws French and German border. This section has been heavily impacted by engineering works during the last two centuries: channelization since 1842 for navigation purposes and the construction of a 45 km long lateral canal and 4 consecutive hydroelectric power plants of since 1932. Several bathymetric models are produced based on 3 different spatial resolutions (6, 13 and 20 cm) and 5 acquisitions (January, March, April, August and October) since 2008. Objectives are to find the optimal spatial resolution and to characterize seasonal effects. Best performances according to the 13 cm resolution show a 18 cm accuracy when suspended matters impacted less water transparency. Discussions are oriented to the monitoring of the artificial reload after 2 flood events during winter 2010-2011. Bathymetric models produced are also useful to build 2D hydraulic model's mesh.

  1. Saturn's rings - high resolution

    Science.gov (United States)

    1981-01-01

    Voyager 2 obtained this high-resolution picture of Saturn's rings Aug. 22, when the spacecraft was 4 million kilometers (2.5 million miles) away. Evident here are the numerous 'spoke' features, in the B-ring; their very sharp, narrow appearance suggests short formation times. Scientists think electromagnetic forces are responsible in some way for these features, but no detailed theory has been worked out. Pictures such as this and analyses of Voyager 2's spoke movies may reveal more clues about the origins of these complex structures. The Voyager project is managed for NASA by the Jet Propulsion Laboratory, Pasadena, Calif.

  2. Temporal bone dissection simulator for training pediatric otolaryngology surgeons

    Science.gov (United States)

    Tabrizi, Pooneh R.; Sang, Hongqiang; Talari, Hadi F.; Preciado, Diego; Monfaredi, Reza; Reilly, Brian; Arikatla, Sreekanth; Enquobahrie, Andinet; Cleary, Kevin

    2017-03-01

    Cochlear implantation is the standard of care for infants born with severe hearing loss. Current guidelines approve the surgical placement of implants as early as 12 months of age. Implantation at a younger age poses a greater surgical challenge since the underdeveloped mastoid tip, along with thin calvarial bone, creates less room for surgical navigation and can result in increased surgical risk. We have been developing a temporal bone dissection simulator based on actual clinical cases for training otolaryngology fellows in this delicate procedure. The simulator system is based on pre-procedure CT (Computed Tomography) images from pediatric infant cases (surgery environment, (2) a newly developed haptic interface for holding the surgical drill, (3) an Oculus Rift to provide a microscopic-like view of the temporal bone surgery, and (4) user interface to interact with the simulator through the Oculus Rift and the haptic device. To evaluate the system, we have collected 10 representative CT data sets and segmented the key structures: cochlea, round window, facial nerve, and ossicles. The simulator will present these key structures to the user and warn the user if needed by continuously calculating the distances between the tip of surgical drill and the key structures.

  3. Compromised trabecular microarchitecture and lower finite element estimates of radius and tibia bone strength in adults with turner syndrome: a cross-sectional study using high-resolution-pQCT.

    Science.gov (United States)

    Hansen, Stinus; Brixen, Kim; Gravholt, Claus H

    2012-08-01

    Although bone mass appear ample for bone size in Turner syndrome (TS), epidemiological studies have reported an increased risk of fracture in TS. We used high-resolution peripheral quantitative computed tomography (HR-pQCT) to measure standard morphological parameters of bone geometry and microarchitecture, as well as estimated bone strength by finite element analysis (FEA) to assess bone characteristics beyond bone mineral density (BMD) that possibly contribute to the increased risk of fracture. Thirty-two TS patients (median age 35, range 20-61 years) and 32 healthy control subjects (median age 36, range 19-58 years) matched with the TS participants with respect to age and body-mass index were studied. A full region of interest (ROI) image analysis and a height-matched ROI analysis adjusting for differences in body height between groups were performed. Mean bone cross-sectional area was lower in TS patients in radius (-15%) and tibia (-13%) (both p radius (18%, p radius, -36% in tibia, both p radius, -22% in tibia, both p radius, -12% in tibia, both p radius, 23% in tibia, both p radius, and trabecular number in tibia. FEA estimated failure load was lower in TS patients in both radius (-11%) and tibia (-16%) (both p < 0.01) and remained significantly lower in the height-matched ROI analysis. Conclusively, TS patients had compromised trabecular microarchitecture and lower bone strength at both skeletal sites, which may partly account for the increased risk of fracture observed in these patients.

  4. [A case of chondroblastoma arising from the temporal bone].

    Science.gov (United States)

    Tsutsumi, Satoshi; Mishima, Yumiko; Nonaka, Yasuomi; Abe, Yusuke; Yasumoto, Yukimasa; Ito, Masanori

    2010-11-01

    A 33-year-old male sustained hearing disturbance in the left ear that exacerbated over a period of three years. The patient was referred to the department of otorhynolaryngology for severe stenosis of the left external auditory canal, where neuroimaging study revealed a huge tumor in the left temporal fossa. On first examination, he showed a significant facial nerve paresis and conductive hearing loss. CT scans identified a 4.5×4.5×4.5 cm mass with intralesional calcification and extensive bony destruction in the squamous and petrous parts of the temporal bone and middle cranial fossa floor. MR imaging demonstrated the tumor of heterogenous intensity on T1-and hypointensity on T2-weighted image. The patient underwent gross total resection of the lesion via frontotemporal craniotomy. The bony and ligamentous structures around the temporomandibular joint appeared mostly intact and did not need any reconstructive surgery after tumor resection. Postoperatively the patient's facial nerve paresis showed a transient exacerbation which resolved gradually, while hearing disturbance did not improve. Histological findings of the tumor were consistent with the qualities of chondroblastoma. We should assume chondroblastoma as differential diagnosis when we encounter a temporal bone tumor that is curable by surgical resection.

  5. Using high-resolution soil moisture modelling to assess the uncertainty of microwave remotely sensed soil moisture products at the correct spatial and temporal support

    Science.gov (United States)

    Wanders, N.; Karssenberg, D.; Bierkens, M. F. P.; Van Dam, J. C.; De Jong, S. M.

    2012-04-01

    Soil moisture is a key variable in the hydrological cycle and important in hydrological modelling. When assimilating soil moisture into flood forecasting models, the improvement of forecasting skills depends on the ability to accurately estimate the spatial and temporal patterns of soil moisture content throughout the river basin. Space-borne remote sensing may provide this information with a high temporal and spatial resolution and with a global coverage. Currently three microwave soil moisture products are available: AMSR-E, ASCAT and SMOS. The quality of these satellite-based products is often assessed by comparing them with in-situ observations of soil moisture. This comparison is however hampered by the difference in spatial and temporal support (i.e., resolution, scale), because the spatial resolution of microwave satellites is rather low compared to in-situ field measurements. Thus, the aim of this study is to derive a method to assess the uncertainty of microwave satellite soil moisture products at the correct spatial support. To overcome the difference in support size between in-situ soil moisture observations and remote sensed soil moisture, we used a stochastic, distributed unsaturated zone model (SWAP, van Dam (2000)) that is upscaled to the support of different satellite products. A detailed assessment of the SWAP model uncertainty is included to ensure that the uncertainty in satellite soil moisture is not overestimated due to an underestimation of the model uncertainty. We simulated unsaturated water flow up to a depth of 1.5m with a vertical resolution of 1 to 10 cm and on a horizontal grid of 1 km2 for the period Jan 2010 - Jun 2011. The SWAP model was first calibrated and validated on in-situ data of the REMEDHUS soil moisture network (Spain). Next, to evaluate the satellite products, the model was run for areas in the proximity of 79 meteorological stations in Spain, where model results were aggregated to the correct support of the satellite

  6. High Resolution Laboratory Spectroscopy

    CERN Document Server

    Brünken, Sandra

    2016-01-01

    In this short review we will highlight some of the recent advancements in the field of high-resolution laboratory spectroscopy that meet the needs dictated by the advent of highly sensitive and broadband telescopes like ALMA and SOFIA. Among these is the development of broadband techniques for the study of complex organic molecules, like fast scanning conventional absorption spectroscopy based on multiplier chains, chirped pulse instrumentation, or the use of synchrotron facilities. Of similar importance is the extension of the accessible frequency range to THz frequencies, where many light hydrides have their ground state rotational transitions. Another key experimental challenge is the production of sufficiently high number densities of refractory and transient species in the laboratory, where discharges have proven to be efficient sources that can also be coupled to molecular jets. For ionic molecular species sensitive action spectroscopic schemes have recently been developed to overcome some of the limita...

  7. Monitoring of the Spatial Distribution and Temporal Dynamics of the Green Vegetation Fraction of Croplands in Southwest Germany Using High-Resolution RapidEye Satellite Images

    Science.gov (United States)

    Imukova, Kristina; Ingwersen, Joachim; Streck, Thilo

    2014-05-01

    The green vegetation fraction (GVF) is a key input variable to the evapotranspiration scheme applied in the widely used NOAH land surface model (LSM). In standard applications of the NOAH LSM, the GVF is taken from a global map with a 15 km×15 km resolution. The central objective of the present study was (a) to derive gridded GVF data in a high spatial and temporal resolution from RapidEye images for a region in Southwest Germany, and (b) to improve the representation of the GVF dynamics of croplands in the NOAH LSM for a better simulation of water and energy exchange between land surface and atmosphere. For the region under study we obtained monthly RapidEye satellite images with a resolution 5 m×5 m by the German Aerospace Center (DLR). The images hold five spectral bands: blue, green, red, red-edge and near infrared (NIR). The GVF dynamics were determined based on the Normalized Difference Vegetation Index (NDVI) calculated from the red and near-infrared bands of the satellite images. The satellite GVF data were calibrated and validated against ground truth measurements. Digital colour photographs above the canopy were taken with a boom-mounted digital camera at fifteen permanently marked plots (1 m×1 m). Crops under study were winter wheat, winter rape and silage maize. The GVF was computed based on the red and the green band of the photographs according to Rundquist's method (2002). Based on the obtained calibration scheme GVF maps were derived in a monthly resolution for the region. Our results confirm a linear relationship between GVF and NDVI and demonstrate that it is possible to determine the GVF of croplands from RapidEye images based on a simple two end-member mixing model. Our data highlight the high variability of the GVF in time and space. At the field scale, the GVF was normally distributed with a coefficient of variation of about 32%. Variability was mainly caused by soil heterogeneities and management differences. At the regional scale the GVF

  8. 10 Yr Spatial and Temporal Trends of PM2.5 Concentrations in the Southeastern US Estimated Using High-resolution Satellite Data

    Science.gov (United States)

    Hu, X.; Waller, L. A.; Lyapustin, A.; Wang, Y.; Liu, Y.

    2013-01-01

    Long-term PM2.5 exposure has been reported to be associated with various adverse health outcomes. However, most ground monitors are located in urban areas, leading to a potentially biased representation of the true regional PM2.5 levels. To facilitate epidemiological studies, accurate estimates of spatiotemporally continuous distribution of PM2.5 concentrations are essential. Satellite-retrieved aerosol optical depth (AOD) has been widely used for PM2.5 concentration estimation due to its comprehensive spatial coverage. Nevertheless, an inherent disadvantage of current AOD products is their coarse spatial resolutions. For instance, the spatial resolutions of the Moderate Resolution Imaging Spectroradiometer (MODIS) and the Multiangle Imaging SpectroRadiometer (MISR) are 10 km and 17.6 km, respectively. In this paper, a new AOD product with 1 km spatial resolution retrieved by the multi-angle implementation of atmospheric correction (MAIAC) algorithm was used. A two-stage model was developed to account for both spatial and temporal variability in the PM2.5-AOD relationship by incorporating the MAIAC AOD, meteorological fields, and land use variables as predictors. Our study area is in the southeastern US, centered at the Atlanta Metro area, and data from 2001 to 2010 were collected from various sources. The model was fitted for each year individually, and we obtained model fitting R2 ranging from 0.71 to 0.85, MPE from 1.73 to 2.50 g m3, and RMSPE from 2.75 to 4.10 g m3. In addition, we found cross validation R2 ranging from 0.62 to 0.78, MPE from 2.00 to 3.01 g m3, and RMSPE from 3.12 to 5.00 g m3, indicating a good agreement between the estimated and observed values. Spatial trends show that high PM2.5 levels occurred in urban areas and along major highways, while low concentrations appeared in rural or mountainous areas. A time series analysis was conducted to examine temporal trends of PM2.5 concentrations in the study area from 2001 to 2010. The results showed

  9. Simultaneous 3D segmentation of three bone compartments on high resolution knee MR images from osteoarthritis initiative (OAI) using graph cuts

    Science.gov (United States)

    Shim, Hackjoon; Kwoh, C. Kent; Yun, Il Dong; Lee, Sang Uk; Bae, Kyongtae

    2009-02-01

    Osteoarthritis (OA) is associated with degradation of cartilage and related changes in the underlying bone. Quantitative measurement of those changes from MR images is an important biomarker to study the progression of OA and it requires a reliable segmentation of knee bone and cartilage. As the most popular method, manual segmentation of knee joint structures by boundary delineation is highly laborious and subject to user-variation. To overcome these difficulties, we have developed a semi-automated method for segmentation of knee bones, which consisted of two steps: placement of seeds and computation of segmentation. In the first step, seeds were placed by the user on a number of slices and then were propagated automatically to neighboring images. The seed placement could be performed on any of sagittal, coronal, and axial planes. The second step, computation of segmentation, was based on a graph-cuts algorithm where the optimal segmentation is the one that minimizes a cost function, which integrated the seeds specified by the user and both the regional and boundary properties of the regions to be segmented. The algorithm also allows simultaneous segmentation of three compartments of the knee bone (femur, tibia, patella). Our method was tested on the knee MR images of six subjects from the osteoarthritis initiative (OAI). The segmentation processing time (mean+/-SD) was (22+/-4)min, which is much shorter than that by the manual boundary delineation method (typically several hours). With this improved efficiency, our segmentation method will facilitate the quantitative morphologic analysis of changes in knee bones associated with osteoarthritis.

  10. Langerhans' Cell Histiocytosis (Histiocytosis X) of the Temporal Bone

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    Objectives Langerhans' Cell histiocytosis (LCH) is a rare disease, which remains poorly understood and whose cellular origin remains unknown. To increase understanding of temporal bone LCH, it is necessary to study recent advances in the diagnosis and treatment of this disease. Methods The long term(5 to 30 years) results of 21 temporal bone LCH cases treated between 1973 and 2003 were reviewed. Surgery, radiotherapy,pharmacologic therapy or a combination of these treatments were employed in these cases. Results Eighteen patients were cured (18/21, 85%). Six patients developed residual diabetes insipidus (DI) and dwarfism (28%).Three patients died (14%). Conclusions The Alessi classification system for LCH based on the extent of disease accurately predicts prognosis and is a useful guide in selecting treatment methodologies. X-ray, computed tomography and magnetic resonance imaging have proved useful in defining the extent of osseous and soft tissue diseases. Diagnosis of LCH is based on clinical presentations, radiographic findings and histopathological results.Surgery and radiotherapy are the main treatment modalities. Pharmacologic therapy should be used in patients with aggressive, disseminate, and refractory lesions. LCH has a predilection for children and prognosis depends on age and extent of vital organ involvement.

  11. Utility of combined high-resolution bone SPECT and MRI for the identification of rheumatoid arthritis patients with high-risk for erosive progression

    Energy Technology Data Exchange (ETDEWEB)

    Buchbender, Christian, E-mail: christian.buchbender@med.uni-duesseldorf.de [Univ Dusseldorf, Medical Faculty, Department of Diagnostic and Interventional Radiology, Moorenstr. 5, D-40225 Dusseldorf (Germany); Sewerin, Philipp, E-mail: philipp.sewerin@med.uni-duesseldorf.de [Univ Dusseldorf, Medical Faculty, Department of Rheumatology, Moorenstr. 5, D-40225 Dusseldorf (Germany); Mattes-György, Katalin, E-mail: katalin.mattes@med.uni-duesseldorf.de [Univ Dusseldorf, Medical Faculty, Department of Nuclear Medicine, Moorenstr. 5, D-40225 Dusseldorf (Germany); Miese, Falk, E-mail: falk.miese@med.uni-duesseldorf.de [Univ Dusseldorf, Medical Faculty, Department of Diagnostic and Interventional Radiology, Moorenstr. 5, D-40225 Dusseldorf (Germany); Wittsack, Hans-Joerg, E-mail: hans-joerg.wittsack@med.uni-duesseldorf.de [Univ Dusseldorf, Medical Faculty, Department of Diagnostic and Interventional Radiology, Moorenstr. 5, D-40225 Dusseldorf (Germany); Specker, Christof, E-mail: c.specker@kliniken-essen-sued.de [Department of Rheumatology and Clinical Immunology, Kliniken Essen-Sud, Propsteistrasse 2, D-45239 Essen (Germany); Antoch, Gerald, E-mail: antoch@med.uni-duesseldorf.de [Univ Dusseldorf, Medical Faculty, Department of Diagnostic and Interventional Radiology, Moorenstr. 5, D-40225 Dusseldorf (Germany); Müller, Hans-Wilhelm, E-mail: HansW.Mueller@med.uni-duesseldorf.de [Univ Dusseldorf, Medical Faculty, Department of Nuclear Medicine, Moorenstr. 5, D-40225 Dusseldorf (Germany); Schneider, Matthias, E-mail: matthias.schneider@med.uni-duesseldorf.de [Univ Dusseldorf, Medical Faculty, Department of Rheumatology, Moorenstr. 5, D-40225 Dusseldorf (Germany); Scherer, Axel, E-mail: scherer@med.uni-duesseldorf.de [Univ Dusseldorf, Medical Faculty, Department of Diagnostic and Interventional Radiology, Moorenstr. 5, D-40225 Dusseldorf (Germany); Ostendorf, Benedikt, E-mail: ostendorf@med.uni-duesseldorf.de [Univ Dusseldorf, Medical Faculty, Department of Rheumatology, Moorenstr. 5, D-40225 Dusseldorf (Germany)

    2013-02-15

    Objectives: To evaluate the utility of sequentially acquired, post hoc fused, magnetic resonance imaging (MRI) and multi-pinhole single photon emission computed tomography (MPH-SPECT) with technetium-99m-labeled disphosphonates (Tc99m-DPD) for the identification of finger joints with later erosive progression in early rheumatoid arthritis (ERA) patients. Methods: Ten consecutive ERA patients prospectively underwent MPH-SPECT and MRI of metacarpophalangeal (MCP) joints prior to and after 6 months methotrexate therapy. Tc99m-DPD uptake was measured at proximal and distal MCP sites using regional analysis. The course of joint pathologies was scored according to the Rheumatoid Arthritis MRI Score (RAMRIS) criteria. Results: The frequency of increased Tc99m-DPD uptake, synovitis and bone marrow edemadecreased under MTX therapy; but the number of bone erosions increased. Joints with progressive and new erosions on follow-up had a higher baseline Tc99m-DPD uptake (2.64 ± 1.23 vs. 1.43 ± 0.91) (p = 0.02). Conclusions: Joints with erosive progression are characterized by an early increased Tc99m-DPD uptake, even in absence of MRI bone pathologies. Tc99m-DPD MPH-SPECT might thus be of additional value to morphological MRI for the identification of RA patients with a high risk for erosive progression.

  12. Osteoradionecrosis of the temporal bone with cancer of the middle ear. A case report

    Energy Technology Data Exchange (ETDEWEB)

    Ishida, Katsunori; Sakai, Makoto [Chigasaki Central Hospital, Kanagawa (Japan); Shinkawa, Atsushi

    1999-12-01

    Osteoradionecrosis of the temporal bone may occur as a result of radiation therapy for head and neck carcinomas or brain tumors. A 64-year-old female received radiation therapy for squamous cell carcinoma of the middle ear 20 years ago, and then she developed osteoradionecrosis of the temporal bone. The patient underwent extensive debridement with removal of sequestrations in the temporal bone and adjacent areas, and abscess drainage. Her postoperative course was satisfactory and there was no progression of the disease. (author)

  13. Primary aneurysmal bone cyst of the petrous temporal bone: A case report and review of literature

    Science.gov (United States)

    Sharma, Mayur; Velho, Vernon; Kharosekar, Hrushikesh

    2016-01-01

    Aneurysmal bone cyst (ABC) arising in the petrous portion of the temporal bone is a rare entity with only five such reported cases in the literature. We report the case of a 28-year-old man who presented with a tender swelling in the right preauricular region with right ear discharge and conductive hearing loss of 4 years' duration. Computed tomography and Magnetic Resonance imaging showed a destructive lesion in the right petrous bone with cavitation consistent with the diagnosis of ABC. Gross total resection of the lesion was achieved and diagnosis was confirmed histologically. The patient had no recurrence at 12 months of follow-up. This report presents the unusual location of an uncommon bony tumor with a review of its clinical, radiological, and histopathological features as well as the treatment modalities available.

  14. Helmholtz-pair transmit coil with integrated receive array for high-resolution MRI of trabecular bone in the distal tibia at 7 T

    Science.gov (United States)

    Wright, Alexander C.; Lemdiasov, Rostislav; Connick, Thomas J.; Bhagat, Yusuf A.; Magland, Jeremy F.; Song, Hee Kwon; Toddes, Steven P.; Ludwig, Reinhold; Wehrli, Felix W.

    2011-05-01

    A Helmholtz-pair local transmit RF coil with an integrated four-element receive array RF coil and foot immobilization platform was designed and constructed for imaging the distal tibia in a whole-body 7 T MRI scanner. Simulations and measurements of the B1 field distribution of the transmit coil are described, along with SAR considerations for operation at 7 T. Results of imaging the trabecular bone of three volunteers at 1.5 T, 3 T and 7 T are presented, using identical 1.5 T and 3 T versions of the 7 T four-element receive array. The spatially registered images reveal improved visibility for individual trabeculae and show average gains in SNR of 2.8× and 4.9× for imaging at 7 T compared to 3 T and 1.5 T, respectively. The results thus display an approximately linear dependence of SNR with field strength and enable the practical utility of 7 T scanners for micro-MRI of trabecular bone.

  15. High Resolution Formaldehyde Photochemistry

    Science.gov (United States)

    Ernest, C. T.; Bauer, D.; Hynes, A. J.

    2010-12-01

    Formaldehyde (HCHO) is the most abundant and most important organic carbonyl compound in the atmosphere. The sources of formaldehyde are the oxidation of methane, isoprene, acetone, and other volatile organic compounds (VOCs); fossil fuel combustion; and biomass burning. The dominant loss mechanism for formaldehyde is photolysis which occurs via two pathways: (R1) HCHO + hv → HCO + H (R2) HCHO + hv → H2 + CO The first pathway (R1) is referred to as the radical channel, while the second pathway (R2) is referred to as the molecular channel. The products of both pathways play a significant role in atmospheric chemistry. The CO that is produced in the molecular channel undergoes further oxidation to produce CO2. Under atmospheric conditions, the H atom and formyl radical that are produced in the radical channel undergo rapid reactions with O2 to produce the hydroperoxyl radical (HO2) via (R3) and (R4). (R3) HCO + O2 → HO2 + CO (R4) H + O2 → HO2 Thus, for every photon absorbed, the photolysis of formaldehyde can contribute one CO2 molecule to the global greenhouse budget or two HO2 radicals to the tropospheric HOx (OH + HO2) cycle. The HO2 radicals produced during formaldehyde photolysis have also been implicated in the formation of photochemical smog. The HO2 radicals act as radical chain carriers and convert NO to NO2, which ultimately results in the catalytic production of O3. Constraining the yield of HO2 produced via HCHO photolysis is essential for improving tropospheric chemistry models. In this study, both the absorption cross section and the quantum yield of the radical channel (R1) were measured at high resolution over the tropospherically relevant wavelength range 304-330 nm. For the cross section measurements a narrow linewidth Nd:YAG pumped dye laser was used with a multi-pass cell. Partial pressures of HCHO were kept below 0.3 torr. Simultaneous measurement of OH LIF in a flame allowed absolute calibration of the wavelength scale. Pressure

  16. Problems of laser vibrometry of temporal bone specimens

    Science.gov (United States)

    Zahnert, Thomas; Vogel, Uwe; Hofmann, Gert; Huettenbrink, Karl-Bernd

    1996-08-01

    Laser vibrometry became a well-established method for vibration detection of solids. By the means of laser Doppler interferometry it is possible to obtain information about displacement and velocity of the system under test. This approach allows the non-contact measurement of small vibrations, and is therefore capable of investigating vibration response of the middle ear ossicles or tympanic membrane due to sound simulation. There have been investigated 20 fresh human temporal bone specimens. Various components related to the sound transmission due to acoustic or mechanic stimulation have been measured by a commercial laser vibrometer (OFV3000 + OFV302/Polytec). Data acquisition, signal processing and test signal generation have been provided by a signal analyzer B&K3550/Bruel&Kjaer or integrated into a Notebook PC. The samples became prepared to allow laser beam access to the regions of interest. Generally our experiments show the capability of laser vibration measurements of the temporal bone specimen for middle ear sound transmission investigations. But the complexity is limiting that method unfortunately. 1D detection could represent insufficient information about the acoustic transmission characteristics only. The request of possibly 3D scanning is limited by anatomic conditions, e.g., according to the narrowness of the tympanic cavity. Nevertheless, for specific problems, e.g., investigation of spatially resolved tympanic membrane vibration characteristics, laser vibrometry performs a unique and high-sensitive approach. After removing the external ear canal different, well-defined points of the tympanic membrane surface have been manually scanned by the open laser beam. Particular care has been taken of the problem of perpendicular beam incidence, in order to detect identical vector components of the vibration amplitude. Laser vibrometry becomes suitable for functional investigation of the vibrating system `ear' influenced by boundary condition changes too

  17. A case of mushroom shape temporal bone osteoma.

    Science.gov (United States)

    Akamatsu, Tadashi; Tanaka, Rica; Fukui, Tsuyoshi; Miyasaka, Muneo; Yamada, Shinya

    2009-09-20

    A cranial vault Osteoma is relatively common benign tumor. Mushroom shaped skull osteoma is, however, extremely rare. Twenty seven years old female developed slow growing hard mass posterior to the ear. CT scan revealed a mushroom shaped osseous mass approximately 2.5 cm in diameter protruding from the temporal bone at the site of asterion. And the tumor was located over the right sigmoid sinus. The sigmoid sinus engraved approximately 4mm to the tumor and had a branching to one emissaries' vein. Operation was performed under general anesthesia. The tumor was excised first by cutting the base of the tumor, and then residual tumor was grinded using a round head cutting bar. A chisel dissection was not recommended because of underlining sinus. Histological findings were consistent with a benign osteoma. The postoperative course was uneventful. CT examination immediately done after operation revealed no evidence of intracranial hemorrhage, or injury of vessels. Osetoma was excised, and the surface of cranial bone at the operation site was smooth and cosmetically acceptable. At 6-months follow up, patient remains asymptomatic and recurrence free. CT examination with Multi Planer Reconstruction imaging or 3D reconstruction is highly recommended for the operational planning of cranial osteoma.

  18. High-resolution peripheral quantitative computed tomography and finite element analysis of bone strength at the distal radius in ovariectomized adult rhesus monkey demonstrate efficacy of odanacatib and differentiation from alendronate.

    Science.gov (United States)

    Cabal, Antonio; Jayakar, Richa Y; Sardesai, Swanand; Phillips, Eual A; Szumiloski, John; Posavec, Diane J; Mathers, Parker D; Savitz, Alan T; Scott, Boyd B; Winkelmann, Christopher T; Motzel, Sherri; Cook, Lynn; Hargreaves, Richard; Evelhoch, Jeffrey L; Dardzinski, Bernard J; Hangartner, Thomas N; McCracken, Paul J; Duong, Le T; Williams, Donald S

    2013-10-01

    Translational evaluation of disease progression and treatment response is critical to the development of therapies for osteoporosis. In this study, longitudinal in-vivo monitoring of odanacatib (ODN) treatment efficacy was compared to alendronate (ALN) in ovariectomized (OVX) non-human primates (NHPs) using high-resolution peripheral computed tomography (HR-pQCT). Treatment effects were evaluated using several determinants of bone strength, density and quality, including volumetric bone mineral density (vBMD), three-dimensional structure, finite element analysis (FEA) estimated peak force and biomechanical properties at the ultradistal (UD) radius at baseline, 3, 6, 9, 12, and 18 months of dosing in three treatment groups: vehicle (VEH), low ODN (2 mg/kg/day, L-ODN), and ALN (30 μg/kg/week). Biomechanical axial compression tests were performed at the end of the study. Bone strength estimates using FEA were validated by ex-vivo mechanical compression testing experiments. After 18months of dosing, L-ODN demonstrated significant increases from baseline in integral vBMD (13.5%), cortical thickness (24.4%), total bone volume fraction BV/TV (13.5%), FEA-estimated peak force (26.6%) and peak stress (17.1%), respectively. Increases from baseline for L-ODN at 18 months were significantly higher than that for ALN in DXA-based aBMD (7.6%), cortical thickness (22.9%), integral vBMD (12.2%), total BV/TV (10.1%), FEA peak force (17.7%) and FEA peak stress (11.5%), respectively. These results demonstrate a superior efficacy of ODN treatment compared to ALN at the UD radii in ovariectomized NHPs.

  19. Anatomic and Quantitative Temporal Bone CT for Preoperative Assessment of Branchio-Oto-Renal Syndrome.

    Science.gov (United States)

    Ginat, D T; Ferro, L; Gluth, M B

    2016-12-01

    We describe the temporal bone computed tomography (CT) findings of an unusual case of branchio-oto-renal syndrome with ectopic ossicles that are partially located in the middle cranial fossa. We also describe quantitative temporal bone CT assessment pertaining to cochlear implantation in the setting of anomalous cochlear anatomy associated with this syndrome.

  20. Statistical model estimating the occurrence of otitis media from temporal bone pneumatization

    DEFF Research Database (Denmark)

    Homøe, P; Lynnerup, N; Rasmussen, N

    1994-01-01

    In order to investigate the relationship between the pneumatization of temporal bones and the occurrence of otitis media in Greenlandic Inuit, 36 Greenlandic Inuit were examined by radiography of the temporal bones. The pneumatized cell area was measured planimetrically. All subjects answered a q...

  1. Histology of sheep temporal bone A histologia do osso temporal do ovino

    Directory of Open Access Journals (Sweden)

    Hormy Biavatti Soares

    2011-06-01

    Full Text Available Previous studies suggest that there is an excellent correlation between the morphology and dimensions of ear structures in sheep and human beings. AIM: To analyze and describe the histology of structures inside the temporal bone in sheep. MATERIAL AND METHODS: A total of 307 slides obtained from vertical and horizontal sections of the temporal bone of eight sheep were analyzed. Structures were classified as similar or not similar to human structures, based on cellularity and histological architecture parameters. STUDY DESIGN: Experimental. RESULTS: The study revealed similarities between sheep and humans in terms of type of epithelium, bone component, spaces in the auditory meatus, in addition to a marked histological resemblance of cellularity and that of the structures surrounding the ear. The main differences observed were the presence of an anatomic bulla, the absence of aeration in the mastoid and the inferior opening of the hypotympanum into the bulla in sheep. CONCLUSION: Based on these observations, it is possible to conclude that sheep represent an adequate option for training and research in otologic surgery.Resultados prévios apontam para uma ótima correlação entre a morfologia e as dimensões das estruturas anatômicas de ovelhas e seres humanos. OBJETIVO: Analisar e descrever a histologia das estruturas que compõem o osso temporal do ovino. MATERIAL E MÉTODO: Um total de 307 lâminas obtidas a partir de secções verticais e horizontais do osso temporal de oito ovelhas foi analisado. As estruturas foram caracterizadas como semelhantes ou não semelhantes às do ser humano, com base na celularidade e na arquitetura histológica das estruturas. DESENHO CIENTÍFICO: Experimental. RESULTADOS: Constatou-se semelhança quanto ao tipo de epitélio, componente ósseo, espaços da fenda auditiva e arquitetura, além da semelhança, em nível histológico, tanto dos componentes celulares como das estruturas contíguas ao ouvido. As

  2. Osteodistrofias raras do osso temporal Rare osteodysplasia of the temporal bone

    Directory of Open Access Journals (Sweden)

    Marcos L. Antunes

    2005-04-01

    Full Text Available As osteodistrofias do osso temporal podem se manifestar de diversas maneiras, como envolvimento restrito ao osso temporal ou com envolvimento de outros ossos do crânio ou ainda fazerem parte de uma manifestação sistêmica. Consideramos, em nosso trabalho, duas entidades como osteodistofias raras, a osteopetrose e a doença de Camurati-Engelmann, esta última de incidência extremamente rara, com poucos relatos na literatura. Apresentamos dois casos de osteopetrose em sua forma benigna (doença de Albers-Schöenberg, um paciente de 11 anos e outro de 48 anos, ambos do sexo masculino, e um paciente de 28 anos do sexo feminino com a doença de Camurati-Engelmann (displasia diafisária hereditária progressiva, doenças hereditárias autossômicas que apresentam sintomas diversos. A paralisia facial periférica se manifestou em dois dos nossos pacientes. Discutimos alguns aspectos relacionados às manifestações clínicas destas doenças, achados radiológicos, assim como o diagnóstico diferencial e a conduta terapêutica diante de complicações das doenças.Temporal bone osteodysplasia can produce many different symptoms, such as involvement restricted to the temporal bone or impairment of other bones. We consider, in this study two entities that are rare osteodysplasia cases, which are osteopetrosis and Camurati-Engelmann disease, the latter being extremely rare. We present two cases of benign form of osteopetrosis (Albers-Schulenburg's disease, a patient of 11 years old and another one of 48 years old, both male, and a patient of 28 years old, female, with Camurati-Engelmann's disease. The facial palsy was a manifestation in two of the patients. We discuss some aspects about the clinical manifestations, radiological findings, as well as differential diagnostic and therapy in view of the complications of the diseases.

  3. High resolution computed tomography for peripheral facial nerve paralysis

    Energy Technology Data Exchange (ETDEWEB)

    Koester, O.; Straehler-Pohl, H.J.

    1987-01-01

    High resolution computer tomographic examinations of the petrous bones were performed on 19 patients with confirmed peripheral facial nerve paralysis. High resolution CT provides accurate information regarding the extent, and usually regarding the type, of pathological process; this can be accurately localised with a view to possible surgical treatments. The examination also differentiates this from idiopathic paresis, which showed no radiological changes. Destruction of the petrous bone, without facial nerve symptoms, makes early suitable treatment mandatory.

  4. [A general review on the procedures in a human temporal bone laboratory].

    Science.gov (United States)

    Oktay, Mehmet Faruk; Cüreoğlu, Sebahattin; Schachern, Patricia A; Paparella, Micheal M

    2006-01-01

    Structures of the human ear are usually inaccessible during life for examination of pathologic changes of the underlying disease, which is only possible with postmortem studies of the human temporal bone. Human temporal bone laboratories serve as a unique source of material for research in this respect. They enable comparison between histologic findings of temporal bone sections and the ear pathologies documented prior to death, as well as comparison of diseased ears with any selected temporal bone specimens, both of which provide invaluable knowledge to be shared among researchers and other laboratories. This article aims to provide insight into the functions of temporal bone laboratories and to familiarize the reader with histopathologic studies conducted therein.

  5. Case of bilateral pneumolabyrinth presenting as sudden, bilateral deafness, without temporal bone fracture, after a fall.

    Science.gov (United States)

    Lee, E J; Yang, Y S; Yoon, Y J

    2012-07-01

    We report a case of bilateral pneumolabyrinth presenting as sudden, bilateral deafness, without temporal bone fracture, after a fall. A 49-year-old man presented with sudden, bilateral deafness and whirling vertigo, without any other neurological manifestations. Temporal bone computed tomography clearly demonstrated the presence of air in the vestibule and cochlea on both sides. However, there was no definite fracture line, ossicular chain anomaly or soft tissue density in the temporal bone or middle-ear cavity. The patient was treated conservatively. Unfortunately, there was no improvement in his hearing. Pneumolabyrinth is an uncommon condition in which air is present in the vestibule or cochlea. It is rarely found, even with fractures violating the otic capsule or with transverse fractures of the temporal bone. In addition, its bilateral occurrence is extremely rare. In this article, we describe a case of bilateral pneumolabyrinth presenting as sudden, bilateral deafness, without temporal bone fracture, an occurrence which has not previously been reported.

  6. An individual drug-therapy and genetic testing report of temporal bone verrucous carcinoma.

    Science.gov (United States)

    Tan, Haolei; Liu, Yong; Zhu, Gangcai; Pi, Leiming; Huang, Donghai; Zhang, Xin

    2014-01-01

    To investigate the pathology and pathogenesis of and treatment methods for temporal bone verrucous carcinoma. A single-patient report of verrucous carcinoma on the left external auditory canal is presented and analyzed along with all cases of temporal bone verrucous carcinoma that have been documented in the English literature. Most of the patients with verrucous carcinoma of the temporal bone have histories of surgery, trauma, or infection, and verrucous carcinomas are sensitive to antimicrotubule chemotherapeutic medicines. Adjuvant radiation therapy is not effective, but surgical treatment might be relatively more effective. Temporal bone verrucous carcinoma has a poor prognosis; therefore, the preferred treatment is surgical resection facilitated with antimicrotubule chemotherapeutic treatment. Adjuvant radiation therapy is not a preferred treatment for temporal bone verrucous carcinoma.

  7. Histopathologic ear findings of syphilis: a temporal bone study.

    Science.gov (United States)

    Hızlı, Ömer; Hızlı, Pelin; Kaya, Serdar; Monsanto, Rafael da Costa; Paparella, Michael M; Cureoglu, Sebahattin

    2016-09-01

    To the best of our knowledge, histopathologic studies of syphilitic ears have generally focused on hydropic changes; so far, no such studies have investigated peripheral vestibular otopathology using differential interference contrast microscopy, in patients with syphilis. For this study, we examined 13 human temporal bone samples from 8 patients with a history of syphilis. Using conventional light microscopy, we performed qualitative histopathologic assessment. In addition, using differential interference contrast microscopy, we performed type I and type II vestibular hair cell counts on each vestibular sense organ with minimal autolysis; in which the neuroepithelium was oriented perpendicular to the plane of section. We then compared vestibular hair cell densities (cells per 0.01 mm² surface area) in the syphilis group vs. the control group. In the syphilis group, we observed precipitate in the endolymphatic or perilymphatic spaces in 1 (7.7 %) of the samples and endolymphatic hydrops in eight (61.5 %) of the samples. Hydrops involved the cochlea (four samples) and/or saccule (four samples). In addition, the syphilis group experienced a significant loss of type II vestibular hair cells in the maculae of the utricle and saccule, and in the cristae of the lateral and posterior semicircular canals, as compared with the control group (P < 0.05).

  8. HYPEROSTOSIS OF THE FRONTAL, TEMPORAL, AND SPHENOID BONES: CASE REPORT AND REVIEW OF LITERATURE

    Directory of Open Access Journals (Sweden)

    Austin Huy Nguyen

    2015-03-01

    Full Text Available Hyperostosis of the internal table of the frontal bone is not an uncommon phenomenon. However, such hyperostosis of the temporal and/or sphenoid bone is rarely discussed in the available literature, especially in the absence of meningioma. We report a case of hyperostosis of the frontal, temporal, and sphenoid bones found during routine cadaveric dissection of an 81 year-old female. Histology revealed thickening and increased density of the lamellar bone. The periosteum was unaffected. Possible etiology is discussed.

  9. Fuzzy logic structure analysis of trabecular bone of the calcaneus to estimate proximal femur fracture load and discriminate subjects with and without vertebral fractures using high-resolution magnetic resonance imaging at 1.5 T and 3 T.

    Science.gov (United States)

    Patel, Priyesh V; Eckstein, Felix; Carballido-Gamio, Julio; Phan, Catherine; Matsuura, Maiko; Lochmüller, Eva-Maria; Majumdar, Sharmila; Link, Thomas M

    2007-10-01

    Newly developed fuzzy logic-derived structural parameters were used to characterize trabecular bone architecture in high-resolution magnetic resonance imaging (HR-MRI) of human cadaver calcaneus specimens. These parameters were compared to standard histomorphological structural measures and analyzed concerning performance in discriminating vertebral fracture status and estimating proximal femur fracture load. Sets of 60 sagittal 1.5 T and 3.0 T HR-MRI images of the calcaneus were obtained in 39 cadavers using a fast gradient recalled echo sequence. Structural parameters equivalent to bone histomorphometry and fuzzy logic-derived parameters were calculated using two chosen regions of interest. Calcaneal, spine, and hip bone mineral density (BMD) measurements were also obtained. Fracture status of the thoracic and lumbar spine was assessed on lateral radiographs. Finally, mechanical strength testing of the proximal femur was performed. Diagnostic performance in discriminating vertebral fracture status and estimating femoral fracture load was calculated using regression analyses, two-tailed t-tests of significance, and receiver operating characteristic (ROC) analyses. Significant correlations were obtained at both field strengths between all structural and fuzzy logic parameters (r up to 0.92). Correlations between histomorphological or fuzzy logic parameters and calcaneal BMD were mostly significant (r up to 0.78). ROC analyses demonstrated that standard structural parameters were able to differentiate persons with and without vertebral fractures (area under the curve [A(Z)] up to 0.73). However, none of the parameters obtained in the 1.5-T images and none of the fuzzy logic parameters discriminated persons with and without vertebral fractures. Significant correlations were found between fuzzy or structural parameters and femoral fracture load. Using multiple regression analysis, none of the structural or fuzzy parameters were found to add discriminative value to BMD

  10. CT VIRTUAL ENDOSCOPY IN ASSESSING OSSICULAR CHAIN DISRUPTION CSUSED BY TEMPORAL BONE FRACTURE AND EAR TRAUMA

    Institute of Scientific and Technical Information of China (English)

    JIANG Lixin; XIAO Zhiwen

    2013-01-01

    Objective To explore the value of computed tomography virtual endoscopy (VE) in assessing ossicular chain disruption in temporal bone fracture and ear trauma with intact tympanum. Methods High resolution spiral computerized tomography (CT) was completed in 35 cases of temporal bone fracture and 5 cases of tympanum trauma, all with intact or healed tympanum. Three-dimensional reconstruction was completed us-ing a virtual endoscopy software. Audiological tests were conducted in all patients and evaluation of facial nerve injury in patients with facial paralysis. Patients with mild conductive deafness, ossicular chain sublux-ation on VE, and no facial paralysis were treated conservatively for 4-12 weeks with repeated hearing evalu-ation; those with facial paralysis underwent surgery if no recovery after 4-8 weeks of conservative treat-ment. Patients with moderate to severe conductive hearing loss or mixed hearing loss, incus long process fracture or dislocation on VE and facial paralysis, underwent ossicular chain reconstruction and facial nerve decompression after conservative treatment for 4-8 weeks, or exploratory tympanotomy only if no facial pa-ralysis. VE, audiological tests and facial nerve function tests were repeated in 3-6 months after surgery. Re-sults Of the 6 cases with mild conductive hearing loss, ossicular chain subluxation and no facial paralysis, 3 recovered to normal hearing spontaneously and 3 showed no significant improvement, after 4-12 weeks of conservative treatment. After conservative treatment for 4-8 weeks, 3 of the 12 cases with mild conductive deafness, ossicular chain dislocation on VE and facial paralysis recovered to normal hearing and House-Brackmann (HB) grade I facial function from HB grade II ,4 showed facial function recovery to HB grade I (n=2) or II (n=2) from HB grade III but no hearing recovery, and 5 gained no recovery and went on to receive exploratory tympanotomy and facial nerve decompression. The 11 cases with moderate to

  11. Three-dimensional CT imaging with a helical scan on temporal bone

    Energy Technology Data Exchange (ETDEWEB)

    Gong, Honghan; Hiraishi, Kumiko; Uesugi, Yasuo; Sakakura, Atsushi; Yoshikawa, Shuji; Shimizu, Takaya; Sueyoshi, Kozo; Narabayashi, Isamu [Osaka Medical Coll., Takatsuki (Japan)

    1996-06-01

    To evaluate the usefulness of three-dimensional (3D) CT on the lesions of temporal bone, we studied 19 patients with disorders on the region of temporal bone by high speed helical CT. The results showed that 8 patients with congenital hearing disorder had deficiency of the auditory ossicles, 2 patients with chronic otitis media had deformity and shortness of the auditory ossicles, 4 patients with trauma had fracture of the temporal bone (1 patient was complicated by doubtful fracture of the incus), 5 patients (4 patients with acquired hearing disorder and 1 patient with otorrhea) had space-occupying lesions. 3-D helical CT could detect abnormal findings on all the patients and it was an important examination for the temporal bone. (author)

  12. Osteoradionecrosis of sphenoid and temporal bones in a patient with maxillary sinus carcinoma: A case report

    Energy Technology Data Exchange (ETDEWEB)

    Inokuchi, T.; Sano, K.; Kaminogo, M. (Nagasaki Univ. School of Dentistry (Japan))

    1990-09-01

    A case of radionecrosis of sphenoid and temporal bones is reported. The patient received a combination of surgery, radiotherapy, and chemotherapy for his left maxillary sinus carcinoma. After the combined therapy, necrosis accompanying inflammation developed in the maxillary and temporal regions. Excision of the necrotic tissues was done, and the left ascending ramus of the mandible was resected because of persistent tumor mass at the left infratemporal fossa. Although the excision wound of the maxilla healed by epithelialization, an area of nonvital bone remained exposed in the temporal region, where progressive osteonecrosis with infection led to breakdown of the skin. The necrotic bones of the zygomatic arch and the sphenotemporal sutural region became visible through the skin defect, and computerized tomography scan revealed bone necrosis involving the inferolateral area and the base of the skull. Excision of the necrotic bone and reconstruction with sternocleidomastoid myocutaneous flap were performed.

  13. Computed tomography of common congenital lesions of the temporal bone

    Energy Technology Data Exchange (ETDEWEB)

    Yuen, H.Y. E-mail: drhyyuen@doctors.org.uk; Ahuja, A.T.; Wong, K.T.; Yue, V.; Hasselt, A.C. van

    2003-09-01

    This pictorial review describes the application of high-resolution computed tomography to the investigation and pre-operative work-up of the common lesions of congenital hearing loss, including congenital aural dysplasia, various congenital ossicular anomalies, inner ear dysmorphology, large vestibular aqueduct syndrome, and congenital absence of cochlear nerve and labyrinthitis ossificans from previous infection. The aim is to help radiologists to provide a more accurate diagnosis of underlying aetiology and assist in surgical planning.

  14. A high-resolution imaging technique using a whole-body, research photon counting detector CT system

    Science.gov (United States)

    Leng, S.; Yu, Z.; Halaweish, A.; Kappler, S.; Hahn, K.; Henning, A.; Li, Z.; Lane, J.; Levin, D. L.; Jorgensen, S.; Ritman, E.; McCollough, C.

    2016-03-01

    A high-resolution (HR) data collection mode has been introduced to a whole-body, research photon-counting-detector CT system installed in our laboratory. In this mode, 64 rows of 0.45 mm x 0.45 mm detector pixels were used, which corresponded to a pixel size of 0.25 mm x 0.25 mm at the iso-center. Spatial resolution of this HR mode was quantified by measuring the MTF from a scan of a 50 micron wire phantom. An anthropomorphic lung phantom, cadaveric swine lung, temporal bone and heart specimens were scanned using the HR mode, and image quality was subjectively assessed by two experienced radiologists. High spatial resolution of the HR mode was evidenced by the MTF measurement, with 15 lp/cm and 20 lp/cm at 10% and 2% modulation. Images from anthropomorphic phantom and cadaveric specimens showed clear delineation of small structures, such as lung vessels, lung nodules, temporal bone structures, and coronary arteries. Temporal bone images showed critical anatomy (i.e. stapes superstructure) that was clearly visible in the PCD system. These results demonstrated the potential application of this imaging mode in lung, temporal bone, and vascular imaging. Other clinical applications that require high spatial resolution, such as musculoskeletal imaging, may also benefit from this high resolution mode.

  15. High-Resolution US of Rheumatologic Diseases.

    Science.gov (United States)

    Taljanovic, Mihra S; Melville, David M; Gimber, Lana H; Scalcione, Luke R; Miller, Margaret D; Kwoh, C Kent; Klauser, Andrea S

    2015-01-01

    For the past 15 years, high-resolution ultrasonography (US) is being routinely and increasingly used for initial evaluation and treatment follow-up of rheumatologic diseases. This imaging technique is performed by using high-frequency linear transducers and has proved to be a powerful diagnostic tool in evaluation of articular erosions, simple and complex joint and bursal effusions, tendon sheath effusions, and synovitis, with results comparable to those of magnetic resonance imaging, excluding detection of bone marrow edema. Crystal deposition diseases including gouty arthropathy and calcium pyrophosphate deposition disease (CPPD) have characteristic appearances at US, enabling differentiation between these two diseases and from inflammatory arthropathies. Enthesopathy, which frequently accompanies psoriatic and reactive arthritis, also has a characteristic appearance at high-resolution US, distinguishing these two entities from other inflammatory and metabolic arthropathies. The presence of Doppler signal in examined joints, bursae, and tendon sheaths indicates active synovitis. Microbubble echo contrast agents augment detection of tissue vascularity and may act in the future as a drug delivery vehicle. Frequently, joint, tendon sheath, and bursal fluid aspirations and therapeutic injections are performed under US guidance. The authors describe the high-resolution US technique including gray-scale, color or power Doppler, and contrast agent-enhanced US that is used in evaluation of rheumatologic diseases of the wrist and hand and the ankle and foot in their routine clinical practice. This article demonstrates imaging findings of normal joints, rheumatoid arthritis, gouty arthritis, CPPD, psoriatic and reactive arthritis, and osteoarthritis.

  16. Inflammatory Pseudotumor of the Temporal Bone: Three Cases and a Review of the Literature

    Directory of Open Access Journals (Sweden)

    Huiqin Tian

    2013-01-01

    Full Text Available Inflammatory pseudotumor (IP is a clinically aggressive but histologically benign condition of unknown cause. Its appearance in the temporal bone is uncommon. We present clinical, radiological, and histopathologic findings of three cases originating in the temporal bone. In the first case, a simultaneous IP of the temporal bone and parotid gland was found with histopathologic confirmation. In the second case, an enlarged cervical node, which was also believed to be related to IP, was observed accompanied with the temporal lesion. While the third case presented with chronic suppurative otitis media. Two of them were treated by surgery alone with complete resolve of the diseases. Another one underwent tympanomastoidectomy in combination with oral steroids, radiation, and chemotherapy, but the IP still recurred. A comprehensive review of the literature on clinical features of the temporal pseudotumor was conducted.

  17. Anatomia do osso temporal de ovelhas sob aspectos didáticos Lambs' temporal bone anatomy under didactic aspects

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    André Gurr

    2011-02-01

    Full Text Available É difícil encontrar ossos temporais humanos para o ensino de cirurgia otológica. Ossos temporais de ovelhas podem representar uma possível alternativa. MATERIAIS E MÉTODOS: Os ossos temporais de ovelhas foram dissecados em um programa convencional de dissecação de osso temporal no laboratório. Incluímos mastoidectomia, abordagens endaurais, mas também analisamos a aparência externa, o meato acústico externo e o hipotímpano. Algumas etapas são diferentes das preparações de ossos humanos. Os resultados morfométricos foram comparados à anatomia conhecida de humanos para verificar se o osso temporal de ovelhas seria utilizável para o ensino de cirurgia otológica. RESULTADOS: O osso temporal de ovelhas parece menor do que o humano. Encontramos uma área bolhosa se estendendo ao hipotímpano abaixo do meato acústico externo. A membrana timpânica é muito semelhante à humana. O meato acústico externo é menor e mais curto. A cadeia ossicular exibe analogias para com a humana. DISCUSSÃO: Esse estudo mostra que especificamente o ouvido médio, a membrana timpânica e o conduto auditivo externo são morfologicamente semelhantes às suas contrapartidas encontradas nos ossos temporais humanos. A ovelha parece ser um modelo viável para o ensino da anatomia do ouvido. A menor escala de algumas estruturas, especialmente dos componentes externos do osso temporal representa uma desvantagem. CONCLUSÕES: A ovelha parece representar uma alternativa viável no ensino de cirurgia otológica.Human temporal bones in teaching ear surgery are rare. The lamb's temporal bone might be a possible alternative. MATERIAL AND METHODS: Temporal bones of the lamb were dissected with a typical temporal bone lab drilling program. We included a mastoidectomy, endaural approaches, but also analyzed the outer appearance, the external ear canal and the hypotympanon. Some steps differed from preparation done in humans. The morphometric results were compared to

  18. High resolution digital delay timer

    Science.gov (United States)

    Martin, Albert D.

    1988-01-01

    Method and apparatus are provided for generating an output pulse following a trigger pulse at a time delay interval preset with a resolution which is high relative to a low resolution available from supplied clock pulses. A first lumped constant delay (20) provides a first output signal (24) at predetermined interpolation intervals corresponding to the desired high resolution time interval. Latching circuits (26, 28) latch the high resolution data (24) to form a first synchronizing data set (60). A selected time interval has been preset to internal counters (142, 146, 154) and corrected for circuit propagation delay times having the same order of magnitude as the desired high resolution. Internal system clock pulses (32, 34) count down the counters to generate an internal pulse delayed by an interval which is functionally related to the preset time interval. A second LCD (184) corrects the internal signal with the high resolution time delay. A second internal pulse is then applied to a third LCD (74) to generate a second set of synchronizing data (76) which is complementary with the first set of synchronizing data (60) for presentation to logic circuits (64). The logic circuits (64) further delay the internal output signal (72) to obtain a proper phase relationship of an output signal (80) with the internal pulses (32, 34). The final delayed output signal (80) thereafter enables the output pulse generator (82) to produce the desired output pulse (84) at the preset time delay interval following input of the trigger pulse (10, 12).

  19. High Resolution Orientation Imaging Microscopy

    Science.gov (United States)

    2012-05-02

    carbon distribution as it relates to the presence of Bainite phase (with small tetragonality) interspersed among the cubic ferrite. An example of the...preferentially segregate. The view offered by these high resolution methods differs from what has been considered before: grains thought to be Bainite

  20. High-Resolution Instrumentation Radar.

    Science.gov (United States)

    1986-09-30

    30 September 1986 Los Angeles Air Force Station 13. NUMBER OF PAGES Los Angeles, Calif. 90009-2960 36 74. MONITORING AGENCY NAME & ADDRESS(If...TREE PLMUT ",-20 -CUTLIASS DumpER SED AN... TREE TRUNK, -0 - MERC BUMPER f - 40 H!-I -50 iI Fig. 7. High-Resolution Instrumentation Radar View of

  1. Aggressive osteoblastoma in mastoid process of temporal bone with facial palsy

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    Manoj Jain

    2013-01-01

    Full Text Available Osteoblastoma is an uncommon primary bone tumor with a predilection for posterior elements of spine. Its occurrence in temporal bone and middle ear is extremely rare. Clinical symptoms are non-specific and cranial nerve involvement is uncommon. The cytomorphological features of osteoblastoma are not very well defined and the experience is limited to only few reports. We report an interesting and rare case of aggressive osteoblastoma, with progressive hearing loss and facial palsy, involving the mastoid process of temporal bone and middle ear along with the description of cyto-morphological features.

  2. Giant cell tumor of the temporal bone – a case report

    Directory of Open Access Journals (Sweden)

    Rao Saraswathi G

    2005-09-01

    Full Text Available Abstract Background Giant cell tumor is a benign but locally aggressive bone neoplasm which uncommonly involves the skull. The petrous portion of the temporal bone forms a rare location for this tumor. Case presentation The authors report a case of a large giant cell tumor involving the petrous and squamous portions of the temporal bone in a 26 year old male patient. He presented with right side severe hearing loss and facial paresis. Radical excision of the tumor was achieved but facial palsy could not be avoided. Conclusion Radical excision of skull base giant cell tumor may be hazardous but if achieved is the optimal treatment and may be curative.

  3. Determination of osteocalcin in meat and bone meal of bovine and porcine origin using matrix-assisted laser desorption ionization/time-of-flight mass spectrometry and high-resolution hybrid mass spectrometry.

    Science.gov (United States)

    Balizs, Gabor; Weise, Christoph; Rozycki, Christel; Opialla, Tobias; Sawada, Stefanie; Zagon, Jutta; Lampen, Alfonso

    2011-05-05

    A method has been developed for determining the origin of meat and bone meal (MBM) by detecting species-specific osteocalcin (OC) using matrix-assisted laser desorption ionization/time-of-flight (MALDI/TOF) and high-resolution hybrid mass spectrometry (HR-Q/TOF MS). The analysis is based on the detection of typical species-specific OC and its tryptic peptide fragments which differ in mass due to differences in the amino-acid sequences between species. After dissolving the MBM samples in EDTA buffer, purification after ultrafiltration was performed using two methods: solid-phase extraction using Zip-Tip C(18) or size exclusion coupled with reverse-phase chromatography. Fractions containing partially purified intact OC were analyzed using LC-Q/TOF and MALDI/TOF mass spectrometry. Species-specific OC was detected at the typical protonated and doubly protonated molecular ions. Furthermore, typical porcine- and bovine-derived tryptic fragments from MBM were detected after enzymatic digestion. In order to determine the underlying amino-acid sequences and to confirm the assignment to OC-derived peptides, MS/MS analysis was carried out. In conclusion, we were able to detect OC in bovine and porcine MBM with high sensitivity and the MS-based method described here by which total OC mass and marker peptides of digested OC are recorded can be used as an alternative approach to detect genus-specific differences in MBM and can be applied as a confirmatory method to mainly immunological osteocalcin screening methods.

  4. Determination of osteocalcin in meat and bone meal of bovine and porcine origin using matrix-assisted laser desorption ionization/time-of-flight mass spectrometry and high-resolution hybrid mass spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Balizs, Gabor, E-mail: gabor.balizs@bfr.bund.de [Federal Institute for Risk Assessment, Thielallee 88-92, D-14195 Berlin (Germany); Weise, Christoph [Freie Universitaet Berlin, Institute for Chemistry and Biochemistry, Thielallee 63, D-14195 Berlin (Germany); Rozycki, Christel; Opialla, Tobias; Sawada, Stefanie; Zagon, Jutta; Lampen, Alfonso [Federal Institute for Risk Assessment, Thielallee 88-92, D-14195 Berlin (Germany)

    2011-05-05

    A method has been developed for determining the origin of meat and bone meal (MBM) by detecting species-specific osteocalcin (OC) using matrix-assisted laser desorption ionization/time-of-flight (MALDI/TOF) and high-resolution hybrid mass spectrometry (HR-Q/TOF MS). The analysis is based on the detection of typical species-specific OC and its tryptic peptide fragments which differ in mass due to differences in the amino-acid sequences between species. After dissolving the MBM samples in EDTA buffer, purification after ultrafiltration was performed using two methods: solid-phase extraction using Zip-Tip C{sub 18} or size exclusion coupled with reverse-phase chromatography. Fractions containing partially purified intact OC were analyzed using LC-Q/TOF and MALDI/TOF mass spectrometry. Species-specific OC was detected at the typical protonated and doubly protonated molecular ions. Furthermore, typical porcine- and bovine-derived tryptic fragments from MBM were detected after enzymatic digestion. In order to determine the underlying amino-acid sequences and to confirm the assignment to OC-derived peptides, MS/MS analysis was carried out. In conclusion, we were able to detect OC in bovine and porcine MBM with high sensitivity and the MS-based method described here by which total OC mass and marker peptides of digested OC are recorded can be used as an alternative approach to detect genus-specific differences in MBM and can be applied as a confirmatory method to mainly immunological osteocalcin screening methods.

  5. TEMPORAL MODELING OF DNA DEGRADATION IN BONE REMAINS

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    Andrei Stefan

    2012-06-01

    Full Text Available The aim of this study is to follow the changes that occur, in time, at DNA level and to establish an efficient and reliable protocol for ancestral DNA extraction from bones found in archaeological sites. To test whether the protocol is efficient and capable of yielding good quality DNA, extraction was first performed on fresh bones. The material consists of fresh pig (Sus scrofa and cow (Bos taurus bones that were grounded by using a drill operating at low speed. The bone powder was then incubated in lysis buffer in the presence of proteinase K. DNA isolation and purification were done by using the phenol:chloroform protocol and DNA was precipitated with absolute ethanol stored at -20oC. The extractions were carried out once every month for a total of four extractions

  6. Cholesterol granuloma of temporal bone: CT and MR findings. Granulomas colesterinicos del hueso temporal: hallazgos por TC y RM

    Energy Technology Data Exchange (ETDEWEB)

    Ruiz Jauriguizuria, J.C.; Ferrero Collado, A.; Ereo Ealo, M.J.; Grande Icaran, D.

    1994-01-01

    Three cases of cholesterol granuloma of the left temporal bone are presented, two located in the petrous apex and the other at the otomastoid level. One of the patients had a history of mastoid surgery and the other surgery of the bone ridge. The three cases were confirmed histologically following surgical resection. The etiopathogenesis of the lesion is discussed, as are the clinical, histological and radiological features, with a broad description of the computed tomography and magnetic resonance findings. The differential diagnosis is also dealt with. (Author)

  7. Temporal Bone Osteomyelitis: The Relationship with Malignant Otitis Externa, the Diagnostic Dilemma, and Changing Trends

    Directory of Open Access Journals (Sweden)

    Jia-Cheng Chen

    2014-01-01

    Full Text Available Fifty-five patients hospitalized for osteomyelitis of the temporal bone between 1990 and 2011 were divided into two study groups: group 1 was patients collected from 1990 to 2001 and group 2 was composed of patients between 2002 and 2011. Clinical diagnostic criteria and epidemiologic data were analyzed to illustrate the altering features of osteomyelitis of the temporal bone. Group 1 patients were characterized by high prevalence of diabetes and more commonly suffered from otalgia, otitis externa and granulation tissue in the external auditory canal and higher positive culture for Pseudomonas aeruginosa. Noticeable changing trends were found between both groups, including declining prevalence of diabetes, fewer patients complaining of pain or presenting with otitis externa, and canal granulation, and increased variety of pathogens in group 2. We should highlight the index of clinical suspicion for osteomyelitis of the temporal bone, even in nondiabetic or immunocompetent patients. Painless otorrhea patients were also at risk of osteomyelitis of the temporal bone, especially patients with previous otologic operation. Increased multiplicity of pathogens amplified the difficulty of diagnosis for osteomyelitis of the temporal bone.

  8. Temporal bone osteomyelitis: the relationship with malignant otitis externa, the diagnostic dilemma, and changing trends.

    Science.gov (United States)

    Chen, Jia-Cheng; Yeh, Chien-Fu; Shiao, An-Suey; Tu, Tzong-Yang

    2014-01-01

    Fifty-five patients hospitalized for osteomyelitis of the temporal bone between 1990 and 2011 were divided into two study groups: group 1 was patients collected from 1990 to 2001 and group 2 was composed of patients between 2002 and 2011. Clinical diagnostic criteria and epidemiologic data were analyzed to illustrate the altering features of osteomyelitis of the temporal bone. Group 1 patients were characterized by high prevalence of diabetes and more commonly suffered from otalgia, otitis externa and granulation tissue in the external auditory canal and higher positive culture for Pseudomonas aeruginosa. Noticeable changing trends were found between both groups, including declining prevalence of diabetes, fewer patients complaining of pain or presenting with otitis externa, and canal granulation, and increased variety of pathogens in group 2. We should highlight the index of clinical suspicion for osteomyelitis of the temporal bone, even in nondiabetic or immunocompetent patients. Painless otorrhea patients were also at risk of osteomyelitis of the temporal bone, especially patients with previous otologic operation. Increased multiplicity of pathogens amplified the difficulty of diagnosis for osteomyelitis of the temporal bone.

  9. Temporal Bone Pneumatization and Pulsatile Tinnitus Caused by Sigmoid Sinus Diverticulum and/or Dehiscence

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    Liu Wenjuan

    2015-01-01

    Full Text Available Background. Although air cells within temporal bone may play an important role in the transmission of pulsatile tinnitus (PT noise, it has not been studied systematically. Purpose. To evaluate the difference in temporal bone pneumatization between PT patients with sigmoid sinus diverticulum and/or dehiscence (SSDD and healthy people. Material and Methods. A total of 199 unilateral persistent PT patients with SSDD and 302 control subjects underwent dual-phase contrast-enhanced CT (DP-CECT, to assess the grade of temporal bone pneumatization in each ear. Results. In the bilateral temporal bone of 302 controls, 16 ears were grade I, 53 were grade II, 141 were grade III, and 394 were grade IV. Among the affected ears of 199 PT cases, 1 ear was grade I, 18 were grade II, 53 were grade III, and 127 were grade IV. There was no significant difference in the pneumatization grade between the affected PT ear and either ear in the healthy subjects (p>0.05.  Conclusion. Although air cells within the temporal bone are an important factor in the occurrence of PT, its severity does not differ significantly from the pneumatization of healthy people.

  10. Evaluation of facial nerve and its landmarks in adult temporal bones

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    Saeid Soheilipour

    2010-06-01

    Full Text Available Introduction: The aim of this study was to identify variations of different segments of facial nerve in temporal bone. Materials and Methods: In this descriptive study that conducted on drilled bones in the temporal bone center of the Al-Zahra Hospital of Isfahan University of Medical Sciences, the landmarks of facial nerve in temporal bone were identified as separate variables and their distances from outer cortex of temporal bone and Henles spine and distances between different segments of nerve were recorded. Results: In the 50 temporal bones dissected, the distance between the tip of incus short process to the cortex was 14.2±1.96 mm, the distance between the facial recess from the facial nerve to the cortex was 14.5±2.58 mm, the distance between the stylomastoid foramen to the cortex was 20.6±2.49 mm, the distance between the lateral semicircular canal to the cortex was 15.9±2.31 mm and the distance between the sigmoid sinus dome to the cortex was 14.08±2.83 mm. The mean length of tympanic and mastoid segments (2nd and 3rd segments of facial nerve were 11.35±0.68 mm and 13.28±1.11mm, respectively. Conclusion: The mean lengths of segment of facial nerve and distant of landmarks from outer cortex of temporal bone are partially similar compared to those described in the western literature and text books, but different compared to eastern researches.

  11. Temporal bone CT findings of tuberculous otitis media : comparison with chronic otitis media

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    Chang, Jeong A; Rho, Myung Ho; Kim, Young Min; Lee, Ho Seung; Choi, Pil Yeob; Seong, Young Soon; Kwon, Jae Soo; Lee, Sang Wook [Masan Samsung Hospital, Sungkyunkwan Univ. College of Medicine, Seoul (Korea, Republic of); Jung, Keon Sik [Pohang Sunrin Hospital, Pohang (Korea, Republic of)

    1999-06-01

    To compare the differential findings of tuberculous otitis media(TOM) with those of chronic sup purative otitis media with or without cholesteatoma, as seen on high resolution temporal bone CT. We retrospectively reviewed 14 cases of TOM, 30 cases of chronic suppurative otitis media(CSOM), and 30 cases of chronic otitis media with cholesteatoma(Chole). All had been pathologically confirmed. We evaluated the preservation of mastoid cells without sclerotic change, the location and extension of soft tissue to the external auditary canal, and erosion of ossicles, the tegmen tympani, scutum, bony labyrinth, facial nerve canal and sigmoid sinus, and the presence of intracranial complications. Soft tissue in the mastoid antrum was seen in all cases of TOM(100%), 29 cases of CSOM(96.7%), and 26 cases of Chole(86.7%). In contrast, the soft tissue in the entire middle ear cavity was noted in 13 cases of TOM(92.8%), 7 cases of CSOM(23.3%), and 12 cases of Chole(40%). Soft tissue extended to the superior aspect of the external auditory canal in 4 cases of TOM (28.6%) and 5 cases of Chole (16.7%). Mastoid air cells were seen in 9 cases of TOM (64.3%), 4 cases of CSOM (13.3%), and 3 cases of Chole(10%). Ossicular erosion was noted in 6 cases of TOM (42.9%), 12 cases of CSOM (40%), and 26 cases of Chole(86.7%), while in one case of TOM (7.1%), 5 cases of CSOM (16.7%), and 15 cases of Chole(50%) there was erosion of the scutum. In one case of TOM, follow-up CT study after 9 months of antituberculous medication without surgery revealed complete clearing of previously noted soft tissue in the middle ear cavity. Specific CT findings of TOM were not seen, but if there were findings of soft tissue in the entire middle ear cavity, soft tissue extension to the external auditory canal, preservation of mastoid air cells without sclerotic change, and intact scutum, TOM may be differentiated from other chronic otitis media.

  12. Bilateral Facial Paralysis Caused by Bilateral Temporal Bone Fracture: A Case Report and a Literature Review

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    Sultan Şevik Eliçora

    2015-01-01

    Full Text Available Bilateral facial paralysis caused by bilateral temporal bone fracture is a rare clinical entity, with seven cases reported in the literature to date. In this paper, we describe a 40-year-old male patient with bilateral facial paralysis and hearing loss that developed after an occupational accident. On physical examination, House-Brackmann (HB facial paralysis of grade 6 was observed on the right side and HB grade 5 paralysis on the left. Upon temporal bone computed tomography (CT examination, a fracture line exhibiting transverse progression was observed in both petrous temporal bones. Our patient underwent transmastoid facial decompression surgery of the right ear. The patient refused a left-side operation. Such patients require extensive monitoring in intensive care units because the presence of multiple injuries means that facial functions are often very difficult to evaluate. Therefore, delays may ensue in both diagnosis and treatment of bilateral facial paralysis.

  13. High-resolution axial MR imaging of tibial stress injuries

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    Mammoto Takeo

    2012-05-01

    Full Text Available Abstract Purpose To evaluate the relative involvement of tibial stress injuries using high-resolution axial MR imaging and the correlation with MR and radiographic images. Methods A total of 33 patients with exercise-induced tibial pain were evaluated. All patients underwent radiograph and high-resolution axial MR imaging. Radiographs were taken at initial presentation and 4 weeks later. High-resolution MR axial images were obtained using a microscopy surface coil with 60 × 60 mm field of view on a 1.5T MR unit. All images were evaluated for abnormal signals of the periosteum, cortex and bone marrow. Results Nineteen patients showed no periosteal reaction at initial and follow-up radiographs. MR imaging showed abnormal signals in the periosteal tissue and partially abnormal signals in the bone marrow. In 7 patients, periosteal reaction was not seen at initial radiograph, but was detected at follow-up radiograph. MR imaging showed abnormal signals in the periosteal tissue and entire bone marrow. Abnormal signals in the cortex were found in 6 patients. The remaining 7 showed periosteal reactions at initial radiograph. MR imaging showed abnormal signals in the periosteal tissue in 6 patients. Abnormal signals were seen in the partial and entire bone marrow in 4 and 3 patients, respectively. Conclusions Bone marrow abnormalities in high-resolution axial MR imaging were related to periosteal reactions at follow-up radiograph. Bone marrow abnormalities might predict later periosteal reactions, suggesting shin splints or stress fractures. High-resolution axial MR imaging is useful in early discrimination of tibial stress injuries.

  14. Measurements of bone density on high resolution CT in diagnosis of fenestral otosclerosis%高分辨率CT骨密度测量诊断前庭窗型耳硬化症

    Institute of Scientific and Technical Information of China (English)

    邓白茹; 陈燕萍; 易云平; 谭健儿; 吴俊铠

    2014-01-01

    目的 探讨应用高分辨率CT(HRCT)骨密度测量法诊断耳硬化症的应用价值.方法 回顾性分析经手术证实的30例耳硬化症患者(耳硬化组)和32名正常对照者(对照组),将ROI置于前庭窗前区进行骨密度CT值测量,并对耳硬化患者进行语频气导和气骨导差听力测试.采用两样本t检验对硬化耳和正常耳骨密度平均CT值进行统计学分析、采用Pearson相关系数分析对耳硬化组平均CT值和听力水平进行分析,并采用ROC曲线分析检测应用CT值诊断耳硬化症的效能.结果 硬化组前庭前区CT值范围462.81~2285.00 HU,平均(1372.82士76.50)HU,对照组前庭前区CT值范围1801.71~2680.55 HU,平均(2171.42士23.53)HU,耳硬化组平均CT值明显低于正常组(P<0.0001);硬化耳平均CT值与语频气导阈值(r=0.18,P=0.19)、与气骨导差(r=-0.01,P=0.93)均无明显相关性.采用平均CT值鉴别耳硬化症的ROC曲线下面积为0.88 (P<0.05),诊断阈值为1938.29 HU,诊断的敏感度为80.7%,特异度为90.6%.结论 骨密度测量对于诊断耳硬化症具有重要应用价值,但其对听力评估的应用有待进一步研究.%Objective To explore the value of bone density measure in the diagnosis of fenestral otosclerosis by high resolution CT (HRCT).Methods Totally 30 patients with otosclerosis (otosclerosis group) proved by operation and 32 normal controls (control group) were analyzed retrospectively.A ROI was placed in the bony labyrinth located anterior to oval window to measure the bone density,and the average for the speech frequency air conduction threshold levels and air-bone gap in otosclerosis group were measured.The mean CT value were compared between otosclerosis group and control group using two-sample t-test,and the correlation between mean CT value and hearing levels were analyzed by pearson correlation coefficient analysis.In addition,the efficiency of mean CT value in diagnosis of otosclerosis were analyzed by

  15. A CASE REPORT OF POST-TRAUMATIC CHOLESTEATOMA FOLLOWING TEMPORAL BONE FRACTURE

    Directory of Open Access Journals (Sweden)

    Vijay

    2016-05-01

    Full Text Available We report a case of chronic suppurative otitis media squamous disease following temporal bone fracture. Patient had road traffic accident and longitudinal fracture with facial palsy four years back with recent onset ear discharge. Upon further evaluation, patient was found to have attic cholesteatoma which was managed with canal wall down mastoidectomy and type IV tympanoplasty. We would like to recommend a longterm follow-up in all cases of temporal bone fracture even with a negative history of prior ear discharge or hard of hearing.

  16. CT-scanning of the temporal bone in an inner ear malformation

    Energy Technology Data Exchange (ETDEWEB)

    Murata, K.; Hosoi, H.; Isono, M.; Ohta, F. (Kinki Univ., Higashi-Osaka, Osaka (Japan))

    1982-05-01

    CT-scanning of the temporal bone revealed a fine contour of the inner ear anomaly in a 8-year-old boy with total deafness on the right. In the inner ear there was a globular mass with a small protrusion anteriorly and with a probably immature superior semi-circular canal. The globular mass was considered to be the utriculosaccular capsule, and the anterior protrusion to be an incipient cochlear duct. CT-scanning of the temporal bone may bring significant progress in diagnosis of inner ear anomalies. Detailed configuration of an inner ear may be shown before histological examination.

  17. Inflammatory diseases of the petrous portion of the temporal bone; Entzuendliche Erkrankungen des Felsenbeins

    Energy Technology Data Exchange (ETDEWEB)

    Koerner, H. [Universitaetsklinikum des Saarlandes, Klinik fuer Diagnostische und Interventionelle Neuroradiologie, Homburg/Saar (Germany)

    2014-04-15

    Inflammatory lesions of the petrous portion of the temporal bone are very common and can be followed by cerebral complications. Thin layer computed tomography (CT) is useful for detecting bony changes of the temporal bone and contrast-enhanced magnetic resonance imaging (CE MRI) is a sensitive method for detecting cerebral complications. (orig.) [German] Entzuendliche Erkrankungen des Felsenbeins sind sehr haeufig und koennen mit zerebralen Komplikationen einhergehen. Mit der Duennschicht-CT lassen sich sehr gut ossaere Veraenderungen im Felsenbein nachweisen. Die kontrastmittelgestuetzte MRT ist sensitiv fuer zerebrale Komplikationen. (orig.)

  18. Displasia fibrosa do osso temporal: relato de dois casos Fibrous dysplasia of the temporal bone: report of two cases

    Directory of Open Access Journals (Sweden)

    Roberto Claudio B. Oliveira

    2004-10-01

    Full Text Available A displasia fibrosa do osso temporal é uma doença de etiologia ainda controversa, manifestando-se principalmente por estenose progressiva do conduto auditivo externo e pela perda condutiva da audição. Outras manifestações incluem abaulamento na região temporal ou retroauricular, otorréia, otalgia e disacusia sensório-neural. A incidência é maior no sexo masculino e acomete principalmente a raça branca. O exame radiológico característico demonstra um aspecto de "vidro-fosco" homogêneo envolvido por uma concha de tecido cortical denso, embora existam outros padrões radiológicos desta enfermidade. O exame microscópico demonstra um trabeculado ósseo semelhante aos caracteres chineses. Este estudo relata dois casos de displasia fibrosa do osso temporal que se destacam, pois ultrapassaram o osso temporal, acometendo a região zigomática, sendo que no segundo caso houve também comprometimento do osso esfenóide e o pterigóide. Os pacientes foram submetidos à mastoidectomia radical modificada e tiveram boa evolução.Fibrous dysplasia of the temporal bone (FDTB is a disorder which etiology is still controversial. Its main clinical feature is a progressive narrowing of the external auditory canal following by conductive hearing loss. Temporal or retroauricular enlargement, ear discharge, otalgia, and sensorineural hearing loss are additional findings. Women and Caucasians are more affected. The prominent finding is a homogeneous radiodense "grounded glass" like image shell surrounded by dense cortical tissue. However, other radiological patterns of this disease may be displayed. Microscopically, a trabecular of bone in "Chinese letter" configuration is found. The two cases of FDTB herein reported are particularly special for a far beyond temporal commitment reaching the zygomatic area in the first case and sphenoid and pterygoid bones in the second one. This infrequent clinical feature with unusual radiological findings made these

  19. Validation of exposure visualization and audible distance emission for navigated temporal bone drilling in phantoms.

    Directory of Open Access Journals (Sweden)

    Eduard H J Voormolen

    Full Text Available BACKGROUND: A neuronavigation interface with extended function as compared with current systems was developed to aid during temporal bone surgery. The interface, named EVADE, updates the prior anatomical image and visualizes the bone drilling process virtually in real-time without need for intra-operative imaging. Furthermore, EVADE continuously calculates the distance from the drill tip to segmented temporal bone critical structures (e.g. the sigmoid sinus and facial nerve and produces audiovisual warnings if the surgeon drills in too close vicinity. The aim of this study was to evaluate the accuracy and surgical utility of EVADE in physical phantoms. METHODOLOGY/PRINCIPAL FINDINGS: We performed 228 measurements assessing the position accuracy of tracking a navigated drill in the operating theatre. A mean target registration error of 1.33±0.61 mm with a maximum error of 3.04 mm was found. Five neurosurgeons each drilled two temporal bone phantoms, once using EVADE, and once using a standard neuronavigation interface. While using standard neuronavigation the surgeons damaged three modeled temporal bone critical structures. No structure was hit by surgeons utilizing EVADE. Surgeons felt better orientated and thought they had improved tumor exposure with EVADE. Furthermore, we compared the distances between surface meshes of the virtual drill cavities created by EVADE to actual drill cavities: average maximum errors of 2.54±0.49 mm and -2.70±0.48 mm were found. CONCLUSIONS/SIGNIFICANCE: These results demonstrate that EVADE gives accurate feedback which reduces risks of harming modeled critical structures compared to a standard neuronavigation interface during temporal bone phantom drilling.

  20. Computed tomography and magnetic resonance imaging of congenital abnormalities of the temporal bone; Computertomographie und Magnetresonanztomographie kongenitaler Veraenderungen des aeusseren Ohrs, Mittel- und Innenohrs sowie des inneren Gehoergangs

    Energy Technology Data Exchange (ETDEWEB)

    Czerny, C.; Imhof, H. [Abteilung fuer Osteologie, Univ.-Klinik fuer Radiodiagnostik, Wien (Austria); Gstoettner, W. [Univ.-Klinik fuer Hals-Nasen-Ohren-Heilkunde, Frankfurt/Main (Germany)

    2003-03-01

    Congenital abnormalities of the temporal bone are mostly accompanied by conductive or sensori-neural hearing loss. Before any therapeutic procedures are done high resolution CT (HRCT) and magnetic resonance imaging (MRI) should be performed to establish the correct diagnosis and to plan the potentially surgical intervention. HRCT best depicts osseous changes especially those of the external auditory canal and the middle ear containing the ossicles and the osseous structures of the temporal bone and the petrous bone containing the inner ear. MRI excellently shows soft tissue changes of the inner ear especially on the high resolution 3DT2-weighted sequences which give a superb contrast between the nerves and the cerebro-spinal fluid. Malformations of the external auditory canal consists of aplasia or hypoplasia and those of the middle ear range form extreme hypoplasia or aplasia to very mild deformations of the ossicles. Malformations of the inner ear also range form complete aplasia to very mild hypoplasia of the organs of the inner ear as well as malformations concerning the nerves in the internal auditory canal range from aplasia to hypoplasia. Malformations of the temporal bone can either occur isolated or in combination in which malformations of the external and middle ear may be accompanied by those of the inner ear. Furthermore, malformations of the temporal bone may also occur in otofacial, otocervical or otoskeletal syndromes. These syndromes may be accompanied by certain malformations of the temporal bone. HRCT and MRI are both excellent methods to depict congenital abnormalities of the temporal bone and of the inner ear and should be used as complementary methods because HRCT best depicts osseous changes and MRI superbly depicts soft tissue changes. Both methods are important to establish the correct diagnosis to plan the therapeutic procedures. (orig.) [German] Angeborene Missbildungen des Schlaefenbeins sind oft mit Schwerhoerigkeit bis Taubheit

  1. High-resolution land topography

    Science.gov (United States)

    Massonnet, Didier; Elachi, Charles

    2006-11-01

    After a description of the background, methods of production and some scientific uses of high-resolution land topography, we present the current status and the prospect of radar interferometry, regarded as one of the best techniques for obtaining the most global and the most accurate topographic maps. After introducing briefly the theoretical aspects of radar interferometry - principles, limits of operation and various capabilities -, we will focus on the topographic applications that resulted in an almost global topographic map of the earth: the SRTM map. After introducing the Interferometric Cartwheel system, we will build on its expected performances to discuss the scientific prospects of refining a global topographic map to sub-metric accuracy. We also show how other fields of sciences such as hydrology may benefit from the products generated by interferometric radar systems. To cite this article: D. Massonnet, C. Elachi, C. R. Geoscience 338 (2006).

  2. High-resolution image analysis.

    Science.gov (United States)

    Preston, K

    1986-01-01

    In many departments of cytology, cytogenetics, hematology, and pathology, research projects using high-resolution computerized microscopy are now being mounted for computation of morphometric measurements on various structural components, as well as for determination of cellular DNA content. The majority of these measurements are made in a partially automated, computer-assisted mode, wherein there is strong interaction between the user and the computerized microscope. At the same time, full automation has been accomplished for both sample preparation and sample examination for clinical determination of the white blood cell differential count. At the time of writing, approximately 1,000 robot differential counting microscopes are in the field, analyzing images of human white blood cells, red blood cells, and platelets at the overall rate of about 100,000 slides per day. This mammoth through-put represents a major accomplishment in the application of machine vision to automated microscopy for hematology. In other areas of automated high-resolution microscopy, such as cytology and cytogenetics, no commercial instruments are available (although a few metaphase-finding machines are available and other new machines have been announced during the past year). This is a disappointing product, considering the nearly half century of research effort in these areas. This paper provides examples of the state of the art in automation of cell analysis for blood smears, cervical smears, and chromosome preparations. Also treated are new developments in multi-resolution automated microscopy, where images are now being generated and analyzed by a single machine over a range of 64:1 magnification and from 10,000 X 20,000 to 500 X 500 in total picture elements (pixels). Examples of images of human lymph node and liver tissue are presented. Semi-automated systems are not treated, although there is mention of recent research in the automation of tissue analysis.

  3. High resolution tomographic instrument development

    Energy Technology Data Exchange (ETDEWEB)

    1992-08-01

    Our recent work has concentrated on the development of high-resolution PET instrumentation reflecting in part the growing importance of PET in nuclear medicine imaging. We have developed a number of positron imaging instruments and have the distinction that every instrument has been placed in operation and has had an extensive history of application for basic research and clinical study. The present program is a logical continuation of these earlier successes. PCR-I, a single ring positron tomograph was the first demonstration of analog coding using BGO. It employed 4 mm detectors and is currently being used for a wide range of biological studies. These are of immense importance in guiding the direction for future instruments. In particular, PCR-II, a volume sensitive positron tomograph with 3 mm spatial resolution has benefited greatly from the studies using PCR-I. PCR-II is currently in the final stages of assembly and testing and will shortly be placed in operation for imaging phantoms, animals and ultimately humans. Perhaps the most important finding resulting from our previous study is that resolution and sensitivity must be carefully balanced to achieve a practical high resolution system. PCR-II has been designed to have the detection characteristics required to achieve 3 mm resolution in human brain under practical imaging situations. The development of algorithms by the group headed by Dr. Chesler is based on a long history of prior study including his joint work with Drs. Pelc and Reiderer and Stearns. This body of expertise will be applied to the processing of data from PCR-II when it becomes operational.

  4. High resolution tomographic instrument development

    Energy Technology Data Exchange (ETDEWEB)

    1992-01-01

    Our recent work has concentrated on the development of high-resolution PET instrumentation reflecting in part the growing importance of PET in nuclear medicine imaging. We have developed a number of positron imaging instruments and have the distinction that every instrument has been placed in operation and has had an extensive history of application for basic research and clinical study. The present program is a logical continuation of these earlier successes. PCR-I, a single ring positron tomograph was the first demonstration of analog coding using BGO. It employed 4 mm detectors and is currently being used for a wide range of biological studies. These are of immense importance in guiding the direction for future instruments. In particular, PCR-II, a volume sensitive positron tomograph with 3 mm spatial resolution has benefited greatly from the studies using PCR-I. PCR-II is currently in the final stages of assembly and testing and will shortly be placed in operation for imaging phantoms, animals and ultimately humans. Perhaps the most important finding resulting from our previous study is that resolution and sensitivity must be carefully balanced to achieve a practical high resolution system. PCR-II has been designed to have the detection characteristics required to achieve 3 mm resolution in human brain under practical imaging situations. The development of algorithms by the group headed by Dr. Chesler is based on a long history of prior study including his joint work with Drs. Pelc and Reiderer and Stearns. This body of expertise will be applied to the processing of data from PCR-II when it becomes operational.

  5. HRSC: High resolution stereo camera

    Science.gov (United States)

    Neukum, G.; Jaumann, R.; Basilevsky, A.T.; Dumke, A.; Van Gasselt, S.; Giese, B.; Hauber, E.; Head, J. W.; Heipke, C.; Hoekzema, N.; Hoffmann, H.; Greeley, R.; Gwinner, K.; Kirk, R.; Markiewicz, W.; McCord, T.B.; Michael, G.; Muller, Jan-Peter; Murray, J.B.; Oberst, J.; Pinet, P.; Pischel, R.; Roatsch, T.; Scholten, F.; Willner, K.

    2009-01-01

    The High Resolution Stereo Camera (HRSC) on Mars Express has delivered a wealth of image data, amounting to over 2.5 TB from the start of the mapping phase in January 2004 to September 2008. In that time, more than a third of Mars was covered at a resolution of 10-20 m/pixel in stereo and colour. After five years in orbit, HRSC is still in excellent shape, and it could continue to operate for many more years. HRSC has proven its ability to close the gap between the low-resolution Viking image data and the high-resolution Mars Orbiter Camera images, leading to a global picture of the geological evolution of Mars that is now much clearer than ever before. Derived highest-resolution terrain model data have closed major gaps and provided an unprecedented insight into the shape of the surface, which is paramount not only for surface analysis and geological interpretation, but also for combination with and analysis of data from other instruments, as well as in planning for future missions. This chapter presents the scientific output from data analysis and highlevel data processing, complemented by a summary of how the experiment is conducted by the HRSC team members working in geoscience, atmospheric science, photogrammetry and spectrophotometry. Many of these contributions have been or will be published in peer-reviewed journals and special issues. They form a cross-section of the scientific output, either by summarising the new geoscientific picture of Mars provided by HRSC or by detailing some of the topics of data analysis concerning photogrammetry, cartography and spectral data analysis.

  6. Quantitative analysis of Neanderthal temporal bone morphology using three-dimensional geometric morphometrics.

    Science.gov (United States)

    Harvati, Katerina

    2003-04-01

    The temporal bone is the location of several traits thought to differentiate Neanderthals from modern humans, including some proposed Neanderthal-derived traits. Most of these, however, are difficult to measure and are usually described qualitatively. This study applied the techniques of geometric morphometrics to the complex morphology of the temporal bone, in order to quantify the differences observed between Neanderthal and modern human anatomy. Two hundred and seventy modern human crania were measured, representing 9 populations of 30 individuals each, and spanning the extremes of the modern human geographical range. Twelve Neanderthal specimens, as well as Reilingen, Kabwe, Skhul 5, Qafzeh 9, and 4 Late Paleolithic European specimens, were included in the fossil sample. The data were collected in the form of three-dimensional (3-D) landmark coordinates, and specimen configurations were superimposed using generalized Procrustes analysis. The fitted coordinates were then analyzed by an array of multivariate statistical methods, including principal components analysis, canonical variates analysis, and Mahalanobis D(2). The temporal bone landmark analysis was very successful in separating Neanderthals from modern humans. Neanderthals were separated from modern humans in both the principal components and canonical variates analyses. They were much further in Mahalanobis distances from all modern human populations than any two modern human groups were from each other. Most of the previously described temporal bone traits contributed to this separation. Copyright 2003 Wiley-Liss, Inc.

  7. Pneumatization of the Temporal Bones in a Greenlandic Inuit Anthropological Material

    DEFF Research Database (Denmark)

    Homøe, P; Lynnerup, N

    1991-01-01

    The degree of pneumatization of the temporal bones correlates with exposure during childhood and adolescence to infectious middle ear diseases (IMED), both acute and chronic. The pneumatized area as seen on cranial X-rays can be measured. This was applied to an anthropological material in order...

  8. Incidental internal carotid artery calcifications on temporal bone CT in children

    Energy Technology Data Exchange (ETDEWEB)

    Koch, Bernadette; Jones, Blaise [Cincinnati Children' s Hospital Medical Center, Department of Radiology, Cincinnati, OH (United States); Blackham, Aaron [University of Cincinnati College of Medicine, Cincinnati, OH (United States)

    2007-02-15

    Incidental internal carotid artery (ICA) calcifications are occasionally noted on CT images of the brain and temporal bone. In adults, incidental calcifications have been correlated with increased incidence of hypercholesterolemia, cardiac disease, diabetes and carotid stenosis. To determine the incidence of incidental calcifications of the carotid siphon on temporal bone CT in children. We retrospectively reviewed 24 months of consecutive temporal bone CT examinations in children aged 18 years and younger. CT examinations on 663 patients were reviewed and the presence or absence of ICA calcifications was ranked as absent, questionable or definitive. In patients in whom definitive calcifications were identified, hospital charts were reviewed for evidence of diabetes mellitus, hypercholesterolemia, hypertriglyceridemia, hyperlipidemia and chronic renal disease as potential causes of early atherosclerosis. Of the 663 patients, 25% had definitive calcifications within the wall of the ICA: 6% of children younger than 2 years and 28% of children 12-19 years of age. Incidentally noted ICA calcifications are a common finding on temporal bone CT in children, most likely a physiologic response to turbulent flow at natural bends in the artery rather than secondary to underlying disease predisposing to early atherosclerotic calcification. (orig.)

  9. Factors Associated with No or Insufficient Temporal Bone Window Using Transcranial Color-coded Sonography

    Directory of Open Access Journals (Sweden)

    Yi-Pin Lin

    2015-09-01

    Conclusion: The failure rate of temporal bone window was considered high as compared to Western countries but, not surprisingly, age and sex remained the significant factors. Introducing echo contrast agents during the TCCS examination might help to increase the success rate of TCCS examination and provide useful information to clinicians.

  10. Successful Function-Preserving Therapy for Chondroblastoma of the Temporal Bone Involving the Temporomandibular Joint

    Directory of Open Access Journals (Sweden)

    Junkichi Yokoyama

    2011-02-01

    Full Text Available We present a case involving a late diagnosis of chondroblastoma of the temporal skull base involving the temporomandibular joint (TMJ. Following an initial misdiagnosis and unsuccessful treatment over a period of 5 years, the patient was referred to our department for further evaluation and possible surgical intervention for occlusal abnormalities, trismus, clicking of the TMJ, and hearing impairment. Based on preoperative immunochemical studies showing positive reaction of multinucleated giant cells for S-100 protein, the final diagnosis was chondroblastoma. The surgical approach – postauricular incision and total parotidectomy, with complete removal of the temporal bone, including the TMJ via the extended middle fossa – was successful in preserving facial nerves and diminishing clinical manifestations. This study highlights a misdiagnosed case in an effort to underline the importance of medical examinations and accurate differential diagnosis in cases involving any tumor mass in the temporal bone.

  11. Successful function-preserving therapy for chondroblastoma of the temporal bone involving the temporomandibular joint.

    Science.gov (United States)

    Yokoyama, Junkichi; Yoshimoto, Hitoshi; Ito, Shin; Ohba, Shinichi; Fujimaki, Mitsuhisa; Ikeda, Katsuhisa; Yazawa, Masaki; Fujimiya, Nozomi; Hanaguri, Makoto

    2011-02-14

    We present a case involving a late diagnosis of chondroblastoma of the temporal skull base involving the temporomandibular joint (TMJ). Following an initial misdiagnosis and unsuccessful treatment over a period of 5 years, the patient was referred to our department for further evaluation and possible surgical intervention for occlusal abnormalities, trismus, clicking of the TMJ, and hearing impairment. Based on preoperative immunochemical studies showing positive reaction of multinucleated giant cells for S-100 protein, the final diagnosis was chondroblastoma. The surgical approach - postauricular incision and total parotidectomy, with complete removal of the temporal bone, including the TMJ via the extended middle fossa - was successful in preserving facial nerves and diminishing clinical manifestations. This study highlights a misdiagnosed case in an effort to underline the importance of medical examinations and accurate differential diagnosis in cases involving any tumor mass in the temporal bone.

  12. Unbiased Stereologic Estimation of the Spatial Distribution of Paget’s Disease in the Human Temporal Bone

    DEFF Research Database (Denmark)

    Bloch, Sune Land; Sørensen, Mads Sølvsten

    2014-01-01

    BACKGROUND: It has been suggested that Paget's disease of bone and otosclerosis may share a myxoviral etiology. However, the association between virus infection and pathologic bone remodeling is still controversial. The aim of this study was to estimate the spatial distribution of pagetic bone...... remodeling around the inner ear space and to compare it with that of otosclerosis in a contemporary context of temporal bone dynamics. MATERIALS AND METHODS: From the temporal bone collection of Massachusetts Eye and Ear Infirmary, 15 of 29 temporal bones with Paget's disease were selected to obtain...... is similar to the normal distribution of perilabyrinthine bone remodeling but entirely different from the spatial location of otosclerosis, which are focal and centripetally distributed around the inner ear space. CONCLUSION: In Paget's disease, the antiresorptive barrier around the inner ear space becomes...

  13. Integrated High Resolution Monitoring of Mediterranean vegetation

    Science.gov (United States)

    Cesaraccio, Carla; Piga, Alessandra; Ventura, Andrea; Arca, Angelo; Duce, Pierpaolo; Mereu, Simone

    2017-04-01

    The study of the vegetation features in a complex and highly vulnerable ecosystems, such as Mediterranean maquis, leads to the need of using continuous monitoring systems at high spatial and temporal resolution, for a better interpretation of the mechanisms of phenological and eco-physiological processes. Near-surface remote sensing techniques are used to quantify, at high temporal resolution, and with a certain degree of spatial integration, the seasonal variations of the surface optical and radiometric properties. In recent decades, the design and implementation of global monitoring networks involved the use of non-destructive and/or cheaper approaches such as (i) continuous surface fluxes measurement stations, (ii) phenological observation networks, and (iii) measurement of temporal and spatial variations of the vegetation spectral properties. In this work preliminary results from the ECO-SCALE (Integrated High Resolution Monitoring of Mediterranean vegetation) project are reported. The project was manly aimed to develop an integrated system for environmental monitoring based on digital photography, hyperspectral radiometry , and micrometeorological techniques during three years of experimentation (2013-2016) in a Mediterranean site of Italy (Capo Caccia, Alghero). The main results concerned the analysis of chromatic coordinates indices from digital images, to characterized the phenological patterns for typical shrubland species, determining start and duration of the growing season, and the physiological status in relation to different environmental drought conditions; then the seasonal patterns of canopy phenology, was compared to NEE (Net Ecosystem Exchange) patterns, showing similarities. However, maximum values of NEE and ER (Ecosystem respiration), and short term variation, seemed mainly tuned by inter annual pattern of meteorological variables, in particular of temperature recorded in the months preceding the vegetation green-up. Finally, green signals

  14. High Resolution Measurement of the Glycolytic Rate

    Science.gov (United States)

    Bittner, Carla X.; Loaiza, Anitsi; Ruminot, Iván; Larenas, Valeria; Sotelo-Hitschfeld, Tamara; Gutiérrez, Robin; Córdova, Alex; Valdebenito, Rocío; Frommer, Wolf B.; Barros, L. Felipe

    2010-01-01

    The glycolytic rate is sensitive to physiological activity, hormones, stress, aging, and malignant transformation. Standard techniques to measure the glycolytic rate are based on radioactive isotopes, are not able to resolve single cells and have poor temporal resolution, limitations that hamper the study of energy metabolism in the brain and other organs. A new method is described in this article, which makes use of a recently developed FRET glucose nanosensor to measure the rate of glycolysis in single cells with high temporal resolution. Used in cultured astrocytes, the method showed for the first time that glycolysis can be activated within seconds by a combination of glutamate and K+, supporting a role for astrocytes in neurometabolic and neurovascular coupling in the brain. It was also possible to make a direct comparison of metabolism in neurons and astrocytes lying in close proximity, paving the way to a high-resolution characterization of brain energy metabolism. Single-cell glycolytic rates were also measured in fibroblasts, adipocytes, myoblasts, and tumor cells, showing higher rates for undifferentiated cells and significant metabolic heterogeneity within cell types. This method should facilitate the investigation of tissue metabolism at the single-cell level and is readily adaptable for high-throughput analysis. PMID:20890447

  15. High resolution measurement of the glycolytic rate

    Directory of Open Access Journals (Sweden)

    Carla X Bittner

    2010-09-01

    Full Text Available The glycolytic rate is sensitive to physiological activity, hormones, stress, aging and malignant transformation. Standard techniques to measure the glycolytic rate are based on radioactive isotopes, are not able to resolve single cells and have poor temporal resolution, limitations that hamper the study of energy metabolism in the brain and other organs. A new method is described in this article, which makes use of a recently-developed FRET glucose nanosensor to measure the rate of glycolysis in single cells with high temporal resolution. Used in cultured astrocytes, the method showed for the first time that glycolysis can be activated within seconds by a combination of glutamate and K+, supporting a role for astrocytes in neurometabolic and neurovascular coupling in the brain. It was also possible to make a direct comparison of metabolism in neurons and astrocytes lying in close proximity, paving the way to a high-resolution characterization of brain energy metabolism. Single-cell glycolytic rates were also measured in fibroblasts, adipocytes, myoblasts and tumor cells, showing higher rates for undifferentiated cells and significant metabolic heterogeneity within cell types. This method should facilitate the investigation of tissue metabolism at the single-cell level and is readily adaptable for high-throughput analysis.

  16. High-resolution infrared imaging

    Science.gov (United States)

    Falco, Charles M.

    2010-08-01

    The hands and mind of an artist are intimately involved in the creative process of image formation, intrinsically making paintings significantly more complex than photographs to analyze. In spite of this difficulty, several years ago the artist David Hockney and I identified optical evidence within a number of paintings that demonstrated artists began using optical projections as early as c1425 - nearly 175 years before Galileo - as aids for producing portions of their images. In the course of our work, Hockney and I developed insights that I have been applying to a new approach to computerized image analysis. Recently I developed and characterized a portable high resolution infrared for capturing additional information from paintings. Because many pigments are semi-transparent in the IR, in a number of cases IR photographs ("reflectograms") have revealed marks made by the artists that had been hidden under paint ever since they were made. I have used this IR camera to capture photographs ("reflectograms") of hundreds of paintings in over a dozen museums on three continents and, in some cases, these reflectograms have provided new insights into decisions the artists made in creating the final images that we see in the visible.

  17. High-Resolution Mass Spectrometers

    Science.gov (United States)

    Marshall, Alan G.; Hendrickson, Christopher L.

    2008-07-01

    Over the past decade, mass spectrometry has been revolutionized by access to instruments of increasingly high mass-resolving power. For small molecules up to ˜400 Da (e.g., drugs, metabolites, and various natural organic mixtures ranging from foods to petroleum), it is possible to determine elemental compositions (CcHhNnOoSsPp…) of thousands of chemical components simultaneously from accurate mass measurements (the same can be done up to 1000 Da if additional information is included). At higher mass, it becomes possible to identify proteins (including posttranslational modifications) from proteolytic peptides, as well as lipids, glycoconjugates, and other biological components. At even higher mass (˜100,000 Da or higher), it is possible to characterize posttranslational modifications of intact proteins and to map the binding surfaces of large biomolecule complexes. Here we review the principles and techniques of the highest-resolution analytical mass spectrometers (time-of-flight and Fourier transform ion cyclotron resonance and orbitrap mass analyzers) and describe some representative high-resolution applications.

  18. Does low-field dedicated extremity MRI (E-MRI) reliably detect bone erosions in rheumatoid arthritis? A comparison of two different E-MRI units and conventional radiography with high-resolution CT scanning

    DEFF Research Database (Denmark)

    Duer-Jensen, A; Ejbjerg, B; Albrecht-Beste, E

    2008-01-01

    OBJECTIVES: To compare the ability of two different E-MRI units and conventional radiography (CR) to identify bone erosions in rheumatoid arthritis (RA) metacarpophalangeal (MCP) and wrist joints with CT scanning as the standard reference method. METHODS: 20 patients with RA and 5 controls...... underwent CR, CT and two E-MRI examinations (Esaote Biomedica Artoscan and MagneVu MV1000) of one hand during a 2-week period. In all modalities, each bone of the wrist and MCP joints was blindly evaluated for erosions. MagneVu images were also assessed for the proportion of each bone being visualised...... were visualised entirely and 37.9% of bones were 67-99% visualised. In MCP joints, 84.2% of bones were visualised entirely and 15.8% of bones were 67-99% visualised. CONCLUSION: With CT as the reference method for detecting erosions in RA hands, the Artoscan showed higher sensitivity than the Magne...

  19. Large capillary hemangioma of the temporal bone with a dural tail sign: A case report

    KAUST Repository

    YANG, GUANG

    2014-05-13

    The present study reports a rare case of large capillary hemangioma of the temporal bone with a dural tail sign. A 57-year-old female presented with pulsatile tinnitus and episodic vertigo associated with a ten-year history of an intermittent faint headache. Magnetic resonance imaging revealed a mass in the right petrous bone, which was hypointense on T1-weighted images and heterogeneously hyperintense on T2-weighted images, and showed a dural tail sign following gadolinium administration. Pre-operatively, this tumor was believed to be a meningioma. During surgery, the vascular tumor was removed by a modified pterional approach. A histopathological examination indicated that the tumor was a capillary hemangioma. Although intraosseous capillary hemangiomas are rare, they most frequently affect the temporal bone. Hemangiomas of the temporal bone may mimic other more common basal tumors. The diagnosis is most often made during surgical resection. The dural tail sign is not specific for meningioma, as it also occurs in other intracranial or extracranial tumors. The treatment of intratemporal hemangiomas is complete surgical excision, with radiotherapy used for unresectable lesions. To the best of our knowledge, the present study is the fourth case of intraosseous intracranial capillary hemangioma, but the largest intratemporal hemangioma to be reported in the literature to date.

  20. Large capillary hemangioma of the temporal bone with a dural tail sign: A case report.

    Science.gov (United States)

    Yang, Guang; Li, Chenguang; Chen, Xin; Liu, Yaohua; Han, Dayong; Gao, Xin; Kawamoto, Keiji; Zhao, Shiguang

    2014-07-01

    The present study reports a rare case of large capillary hemangioma of the temporal bone with a dural tail sign. A 57-year-old female presented with pulsatile tinnitus and episodic vertigo associated with a ten-year history of an intermittent faint headache. Magnetic resonance imaging revealed a mass in the right petrous bone, which was hypointense on T1-weighted images and heterogeneously hyperintense on T2-weighted images, and showed a dural tail sign following gadolinium administration. Pre-operatively, this tumor was believed to be a meningioma. During surgery, the vascular tumor was removed by a modified pterional approach. A histopathological examination indicated that the tumor was a capillary hemangioma. Although intraosseous capillary hemangiomas are rare, they most frequently affect the temporal bone. Hemangiomas of the temporal bone may mimic other more common basal tumors. The diagnosis is most often made during surgical resection. The dural tail sign is not specific for meningioma, as it also occurs in other intracranial or extracranial tumors. The treatment of intratemporal hemangiomas is complete surgical excision, with radiotherapy used for unresectable lesions. To the best of our knowledge, the present study is the fourth case of intraosseous intracranial capillary hemangioma, but the largest intratemporal hemangioma to be reported in the literature to date.

  1. High-resolution slug testing.

    Science.gov (United States)

    Zemansky, G M; McElwee, C D

    2005-01-01

    The hydraulic conductivity (K) variation has important ramifications for ground water flow and the transport of contaminants in ground water. The delineation of the nature of that variation can be critical to complete characterization of a site and the planning of effective and efficient remedial measures. Site-specific features (such as high-conductivity zones) need to be quantified. Our alluvial field site in the Kansas River valley exhibits spatial variability, very high conductivities, and nonlinear behavior for slug tests in the sand and gravel aquifer. High-resolution, multilevel slug tests have been performed in a number of wells that are fully screened. A general nonlinear model based on the Navier-Stokes equation, nonlinear frictional loss, non-Darcian flow, acceleration effects, radius changes in the wellbore, and a Hvorslev model for the aquifer has been used to analyze the data, employing an automated processing system that runs within the Excel spreadsheet program. It is concluded that slug tests can provide the necessary data to identify the nature of both horizontal and vertical K variation in an aquifer and that improved delineation or higher resolution of K structure is possible with shorter test intervals. The gradation into zones of higher conductivity is sharper than seen previously, and the maximum conductivity observed is greater than previously measured. However, data from this project indicate that well development, the presence of fines, and the antecedent history of the well are important interrelated factors in regard to slug-test response and can prevent obtaining consistent results in some cases.

  2. Giant Cell Tumor of the Temporal Bone with Direct Invasion into the Middle Ear and Skull Base: A Case Report

    Directory of Open Access Journals (Sweden)

    Takashi Iizuka

    2012-01-01

    Full Text Available Giant cell tumor (GCT is classified as a benign bone tumor, and it is frequently identified at the epiphysis of long bones and relatively rare in the temporal bone. For orthopedists expert at recognizing bone and soft tissue tumors, the diagnosis of GCT is relatively easy; however, since head and neck surgeons experience few cases of GCT, it may be difficult to diagnose when it occurs in the temporal bone. A 32-year-old man complained of left hearing loss, aural fullness, and tinnitus. Examination of the ear revealed a bulging tumor. Audiologic examination demonstrated conductive hearing loss of the left ear. Computer tomograph of the temporal bone showed a soft-tissue-density specification indicating bone destruction at the left temporal bone. The tumor invaded the skull base. Imaging examinations using magnetic resonance imaging revealed a nonhomogenous isosignal intensity area on T1 at the left temporal bone. After intravenous gadolinium, the mass showed unequal enhancement. This patient subsequently underwent surgery to remove the lesion using transmastoid and middle fossa approach. Pathological examinations from specimens of the tumor revealed characteristic of GCT. No clinical or radiological evidence of tumor recurrence was detected for 4 years.

  3. Does low-field dedicated extremity MRI (E-MRI) reliably detect RA bone erosions? A comparison of two different E-MRI units and conventional radiography with high resolution CT

    DEFF Research Database (Denmark)

    Duer, Anne; Ejbjerg, Bo; Albrecht-Beste, Elisabeth;

    2008-01-01

    underwent, within 2 weeks, CR, CT and two E-MRI (Esaote Biomedica; Artoscan and MagneVu; MV1000) examination of one hand. In all modalities each bone of wrist and (MCP) joints was blindedly evaluated for erosions. Furthermore, MagneVu images were assessed for the proportion of each bone being visualized...

  4. High-resolution spectroscopy of gamma-ray transients

    Energy Technology Data Exchange (ETDEWEB)

    Cline, T.L.

    1988-09-25

    The first high-resolution spectrometer flown to observe gamma-ray bursts was launched on the ISEE-3 spacecraft over nine years ago. It recorded two events before instrument failure, giving results that were suggestive but marginal. Other studies, with coarser energy resolution, also show evidence for spectral features as well as for spectral evolution on short time scales. Absolute source strength calibration will be possible only with source identification, but understanding of the burst emission processes will surely come only from the measurements having the best spectral and temporal precision. The only high- resolution gamma-ray spectrometer now planned, here or abroad, for space flight is an instrument sequel to the ISEE-3 spectrometer, to be flown on the interplanetary 'GGS Wind' mission. Much larger and higher-sensitivity, high-resolution instruments may have their optimum opportunities in conjunction with studies of solar flares in the time frame of the solar maximum of 2002.

  5. Climatologies at high resolution for the Earth land surface areas

    CERN Document Server

    Karger, Dirk Nikolaus; Böhner, Jürgen; Kawohl, Tobias; Kreft, Holger; Soria-Auza, Rodrigo Wilber; Zimmermann, Niklaus; Linder, H Peter; Kessler, Michael

    2016-01-01

    High resolution information of climatic conditions is essential to many application in environmental sciences. Here we present the CHELSA algorithm to downscale temperature and precipitation estimates from the European Centre for Medium-Range Weather Forecast (ECMWF) climatic reanalysis interim (ERA-Interim) to a high resolution of 30 arc sec. The algorithm for temperature is based on a statistical downscaling of atmospheric temperature from the ERA-Interim climatic reanalysis. The precipitation algorithm incorporates orographic predictors such as wind fields, valley exposition, and boundary layer height, and a bias correction using Global Precipitation Climatology Center (GPCC) gridded and Global Historical Climate Network (GHCN) station data. The resulting data consist of a monthly temperature and precipitation climatology for the years 1979-2013. We present a comparison of data derived from the CHELSA algorithm with two other high resolution gridded products with overlapping temporal resolution (Tropical R...

  6. Semicircular canal dehiscence: Frequency and distribution on temporal bone CT and its relationship with the clinical outcomes

    Energy Technology Data Exchange (ETDEWEB)

    Elmali, Muzaffer, E-mail: muzafel@yahoo.com.tr [Department of Radiology, Ondokuz Mayis University, Faculty of Medicine, Samsun (Turkey); Polat, Ahmet Veysel, E-mail: veyselp@hotmail.com [Department of Radiology, Ondokuz Mayis University, Faculty of Medicine, Samsun (Turkey); Kucuk, Harun, E-mail: hardrmd@yahoo.com [Department of Otorhinolaryngology, Ondokuz Mayis University, Faculty of Medicine, Samsun (Turkey); Atmaca, Sinan, E-mail: sinanatmaca@yahoo.com [Department of Otorhinolaryngology, Ondokuz Mayis University, Faculty of Medicine, Samsun (Turkey); Aksoy, Ahmet, E-mail: toxocara47@hotmail.com [Department of Otorhinolaryngology, Ondokuz Mayis University, Faculty of Medicine, Samsun (Turkey)

    2013-10-01

    Purpose: In this study, we aimed to investigate the frequency of SCD and its distribution and relationship with clinical outcomes on thin-section CT of the temporal bone. Materials and methods: Digital temporal bone CT images of 850 consecutive patients (1700 temporal bone CTs, 5100 SCs) who presented with a range of complaints such as vertigo, deafness, ear pain, fullness, and discharge between January 2008 and December 2011 were re-evaluated. Axial and oblique coronal reconstruction images of the temporal bone were made with a reconstruction thickness of 0.5 mm. Additionally, superior SC was evaluated in two perpendicular planes. Results: Out of 850 patients, 70 had completely normal temporal bone CT. Ninety-three patients had at least one SCD. In the temporal bone-based evaluation, 119 (26 bilateral, 67 unilateral) of 1700 temporal bones (7%) showed dehiscence. The SC-based evaluation revealed 125 SCD (2.5%) in 5100 SCs. The total number and rates of SCD were as follows: superior 103 (82.4%), posterior 13 (10.4%), and lateral nine (7.2%). Twenty of the 93 patients with SCD (21.5%) revealed no other findings on their temporal bone CTs. We determined a significant correlation between vestibular complaints, conductive hearing loss and SCD but there was no correlation between mixed, sensorineural hearing loss and SCD. Conclusion: We determined the frequency of SCD in 11% of patients and 7% of temporal bones. With regards to the distribution, the superior SC showed the highest dehiscence rate (82.4%). We found a significant correlation between vestibular symptoms, conductive hearing loss and SCD.

  7. High-resolution intravital microscopy.

    Directory of Open Access Journals (Sweden)

    Volker Andresen

    Full Text Available Cellular communication constitutes a fundamental mechanism of life, for instance by permitting transfer of information through synapses in the nervous system and by leading to activation of cells during the course of immune responses. Monitoring cell-cell interactions within living adult organisms is crucial in order to draw conclusions on their behavior with respect to the fate of cells, tissues and organs. Until now, there is no technology available that enables dynamic imaging deep within the tissue of living adult organisms at sub-cellular resolution, i.e. detection at the level of few protein molecules. Here we present a novel approach called multi-beam striped-illumination which applies for the first time the principle and advantages of structured-illumination, spatial modulation of the excitation pattern, to laser-scanning-microscopy. We use this approach in two-photon-microscopy--the most adequate optical deep-tissue imaging-technique. As compared to standard two-photon-microscopy, it achieves significant contrast enhancement and up to 3-fold improved axial resolution (optical sectioning while photobleaching, photodamage and acquisition speed are similar. Its imaging depth is comparable to multifocal two-photon-microscopy and only slightly less than in standard single-beam two-photon-microscopy. Precisely, our studies within mouse lymph nodes demonstrated 216% improved axial and 23% improved lateral resolutions at a depth of 80 µm below the surface. Thus, we are for the first time able to visualize the dynamic interactions between B cells and immune complex deposits on follicular dendritic cells within germinal centers (GCs of live mice. These interactions play a decisive role in the process of clonal selection, leading to affinity maturation of the humoral immune response. This novel high-resolution intravital microscopy method has a huge potential for numerous applications in neurosciences, immunology, cancer research and

  8. Temporal gene expression profiling during rat femoral marrow ablation-induced intramembranous bone regeneration.

    Directory of Open Access Journals (Sweden)

    Joel K Wise

    Full Text Available Enhanced understanding of differential gene expression and biological pathways associated with distinct phases of intramembranous bone regeneration following femoral marrow ablation surgery will improve future advancements regarding osseointegration of joint replacement implants, biomaterials design, and bone tissue engineering. A rat femoral marrow ablation model was performed and genome-wide microarray data were obtained from samples at 1, 3, 5, 7, 10, 14, 28, and 56 days post-ablation, with intact bones serving as controls at Day 0. Bayesian model-based clustering produced eight distinct groups amongst 9,062 significant gene probe sets based on similar temporal expression profiles, which were further categorized into three major temporal classes of increased, variable, and decreased expression. Osteoblastic- and osteoclastic-associated genes were found to be significantly expressed within the increased expression groups. Chondrogenesis was not detected histologically. Adipogenic marker genes were found within variable/decreased expression groups, emphasizing that adipogenesis was inhibited during osteogenesis. Differential biological processes and pathways associated with each major temporal group were identified, and significantly expressed genes involved were visually represented by heat maps. It was determined that the increased expression group exclusively contains genes involved in pathways for matrix metalloproteinases (MMPs, Wnt signaling, TGF-β signaling, and inflammatory pathways. Only the variable expression group contains genes associated with glycolysis and gluconeogenesis, the notch signaling pathway, natural killer cell mediated cytotoxicity, and the B cell receptor signaling pathway. The decreased group exclusively consists of genes involved in heme biosynthesis, the p53 signaling pathway, and the hematopoietic cell lineage. Significant biological pathways and transcription factors expressed at each time point post

  9. Diagnosis of temporal bone diseases using three-dimensional images with multislice CT

    Energy Technology Data Exchange (ETDEWEB)

    Toyama, Yoshihiro; Togami, Taro; Murota, Makiko; Fukunaga, Kotaro; Hino, Ichiro; Sato, Katashi; Ohkawa, Motoomi [Kagawa Medical Univ., Miki (Japan)

    2001-08-01

    We evaluated the usefulness of three-dimensional images with multislice CT in the temporal bone diseases. Fifty-nine cases (26 with medial otitis, 8 choresteatoma, 10 congenital malformation, 3 high jugular bulb, 2 otosclerosis, and 10 others) were included in this study. In the ossicular and inner ear lesions, oblique multiplanar images of the long axis of each ossicle was useful the detection of abnormality. Structural deformity of ossicles and bony labyrinth were clearly delineated by surface rendering images. (author)

  10. Variability of the temporal bone surface's topography: implications for otologic surgery

    Science.gov (United States)

    Lecoeur, Jérémy; Noble, Jack H.; Balachandran, Ramya; Labadie, Robert F.; Dawant, Benoit M.

    2012-02-01

    Otologic surgery is performed for a variety of reasons including treatment of recurrent ear infections, alleviation of dizziness, and restoration of hearing loss. A typical ear surgery consists of a tympanomastoidectomy in which both the middle ear is explored via a tympanic membrane flap and the bone behind the ear is removed via mastoidectomy to treat disease and/or provide additional access. The mastoid dissection is performed using a high-speed drill to excavate bone based on a pre-operative CT scan. Intraoperatively, the surface of the mastoid component of the temporal bone provides visual feedback allowing the surgeon to guide their dissection. Dissection begins in "safe areas" which, based on surface topography, are believed to be correlated with greatest distance from surface to vital anatomy thus decreasing the chance of injury to the brain, large blood vessels (e.g. the internal jugular vein and internal carotid artery), the inner ear, and the facial nerve. "Safe areas" have been identified based on surgical experience with no identifiable studies showing correlation of the surface with subsurface anatomy. The purpose of our study was to investigate whether such a correlation exists. Through a three-step registration process, we defined a correspondence between each of twenty five clinically-applicable temporal bone CT scans of patients and an atlas and explored displacement and angular differences of surface topography and depth of critical structures from the surface of the skull. The results of this study reflect current knowledge of osteogenesis and anatomy. Based on two features (distance and angular difference), two regions (suprahelical and posterior) of the temporal bone show the least variability between surface and subsurface anatomy.

  11. Tuberculous otitis media: findings on high-resolution CT

    Energy Technology Data Exchange (ETDEWEB)

    Lungenschmid, D. [Dept. of Radiodiagnostics, University Hospital Innsbruck (Austria)]|[Dept. of Magnetic Resonance and Spectroscopy, University Hospital of Innsbruck (Austria); Buchberger, W. [Dept. of Radiodiagnostics, University Hospital Innsbruck (Austria)]|[Dept. of Magnetic Resonance and Spectroscopy, University Hospital of Innsbruck (Austria); Schoen, G. [Dept. of Radiodiagnostics, University Hospital Innsbruck (Austria); Schoepf, R. [Radiologic Inst., Landeck (Austria); Mihatsch, T. [Dept. of Oto-Rhino-Laryngology, University Hospital of Innsbruck (Austria); Birbamer, G. [Dept. of Magnetic Resonance and Spectroscopy, University Hospital of Innsbruck (Austria); Wicke, K. [Inst. of Computed Tomography, University Hospital of Innsbruck (Austria)

    1993-12-01

    We describe two cases of tuberculous otitis media studied with high-resolution computed tomography (CT). Findings included extensive soft tissue densities with fluid levels in the tympanic cavity, the antrum, the mastoid and petrous air cells. Multifocal bony erosions and reactive bone sclerosis were seen as well. CT proved valuable for planning therapy by accurately displaying the involvement of the various structures of the middle and inner ear. However, the specific nature of the disease could only be presumed. (orig.)

  12. Suture restriction of the temporal bone as a risk factor for acute otitis media in children: cohort study

    Directory of Open Access Journals (Sweden)

    Morin Chantal

    2012-11-01

    Full Text Available Abstract Background Eustachian tube (ET dysfunction plays an important role in the pathogenesis of acute otitis media (AOM. Unfortunately, there is a lack of knowledge about the exact role of the ET’s bony support, the temporal bone, on occurrence of AOM. This study investigates whether severe suture restriction of the temporal bone is a risk factor for development of AOM in young children. Methods Using a prospective cohort design, 64 children aged 6 to 18 months without prior history of AOM were followed during the cold season (September 2009 to April 2010. Temporal bone status (categorized as with or without severe suture restriction was evaluated using palpation and a cranial bone mobility test. Information about potential baseline confounders and risk factors for AOM (gender, age, birth weight, gestational age, use of pacifier, daycare attendance, presence of siblings, low socioeconomic status, breastfeeding ≥ 6 months, parental smoking and history of upper respiratory tract infection were also collected. Occurrence of AOM diagnosed by physicians blinded to temporal bone status was the main outcome. Data were analyzed using hierarchical linear and nonlinear (multilevel models. Results Severe suture restriction of the temporal bone was identified in 23 children (35.9%. At least one AOM episode was diagnosed in 14 (48.3% of the ears associated with temporal bones previously identified as having severe suture restriction and in 28 (28.3% of those without severe suture restriction. Higher risk for AOM was explained by severe suture restriction of the temporal bone (adjusted relative risk (RR, 2.26, 95% CI 1.43 to 2.91, p Conclusions The study results indicate that severe suture restriction of the temporal bone is a risk factor for AOM in young children. Subsequent intervention studies are needed to determine if this mechanical risk factor can be modified in young children.

  13. Temporal bone MRI with 3D-FIESTA in the evaluation of facial and audiovestibular dysfunction.

    Science.gov (United States)

    Cavusoglu, M; Cılız, D S; Duran, S; Ozsoy, A; Elverici, E; Karaoglanoglu, R; Sakman, B

    2016-09-01

    To evaluate the clinical usefulness of magnetic resonance imaging (MRI) of the temporal bone using three-dimensional fast imaging employing steady-state acquisition (3D-FIESTA) sequences in patients with facial and audiovestibular dysfunction. We retrospectively reviewed the MR images of 1263 patients who presented with hearing loss (n=429), peripheral facial palsy (n=96), tinnitus (n=341) or vertigo (n=397). There were 605 men and 658 women, with a mean age of 46.97±16.95 (SD) years (range: 2-83 years). Positive MRI findings that were responsible for clinical manifestations in individual patients were categorized according to the anatomic sites and etiologies of the lesions. Positive MRI findings possibly responsible for clinical manifestations were found in 232/1263 (18.37%) patients, including 86/429 (20.05%) patients with hearing loss, 21/96 (21.88%) patients with facial palsy, 62/341 (18.18%) patients with tinnitus, and 63/397 (15.87%) patients with vertigo. Although the use of MRI of the temporal bone using 3D-FIESTA shows positive findings in only 18.37% of patients, it provides important information in those with facial and audiovestibular dysfunction. However, for patients with normal MRI of the temporal bone, other etiological factors should be investigated in order to clarify or elucidate the cause of clinical manifestations. Copyright © 2015 Éditions françaises de radiologie. Published by Elsevier Masson SAS. All rights reserved.

  14. Inflammation and tumors of the temporal bone; Entzuendungen und Tumoren des Schlaefenbeins

    Energy Technology Data Exchange (ETDEWEB)

    Burian, M. [Universitaetsklinik fuer Hals-, Nasen- und Ohrenkrankheiten, Allgemeines Krankenhaus, Wien (Austria)

    1997-12-01

    The term `inflammation of the middle ear` covers a couple of deseases which range from the acute otitis media to the middle ear cholesteatoma. However, a clear characterization of a certain pathology is essential for any further treatment. Therefore this article presents a short overview about the different types of infections and their clinical manifestation. The tumors of the temporal bone show a great variety in their incidence. Even if tumors like the acoustic neurinoma or the paraganglioma are compareable common, the chondroblastoma of the temporal bone is absolutely rare. In spite of these differences the individual temporal bone neoplasias are shortly mentioned herein. (orig.) [Deutsch] Der Begriff Mittelohrentzuendung umfasst ein weites Spektrum von Krankheiten welches von der akuten Mittelohrentzuendung bis hin zum Cholesteatom reicht. Es soll in diesem Artikel eine kurze Uebersicht ueber die verschiedenen Entzuendungen gegeben werden, wobei vor allem auf eine klare Begriffsdefinition der einzelnen Entzuendungsformen und deren klinisches Erscheinungsbild geachtet wurde. Bei den Tumoren des Schlaefenbeins ist ein grosser Unterschied in der Inzidenz der einzelnen Tumoren gegeben. Waehrend Neubildungen wie das Akustikusneurinom oder das Paragangliom vergleichsweise haeufig im klinischen Alltag zu sehen sind, stellen Veraenderungen wie das Chondroblastom eine Raritaet dar. Trotz dieses Unterschieds im Vorkommen der verschiedenen Tumoren, wurde versucht, einen kurzen Gesamtueberblick ueber die Tumore des Mittel- und Innenohres zu geben. (orig.)

  15. Section on High Resolution Optical Imaging (HROI)

    Data.gov (United States)

    Federal Laboratory Consortium — The Section on High Resolution Optical Imaging (HROI) develops novel technologies for studying biological processes at unprecedented speed and resolution. Research...

  16. Morphometrical Study of the Temporal Bone and Auditory Ossicles in Guinea Pig

    Directory of Open Access Journals (Sweden)

    Ahmadali Mohammadpour

    2011-03-01

    Full Text Available In this research, anatomical descriptions of the structure of the temporal bone and auditory ossicles have been performed based on dissection of ten guinea pigs. The results showed that, in guinea pig temporal bone was similar to other animals and had three parts; squamous, tympanic and petrous .The tympanic part was much better developed and consisted of oval shaped tympanic bulla with many recesses in tympanic cavity. The auditory ossicles of guinea pig concluded of three small bones; malleus, incus and stapes but the head of the malleus and the body of incus were fused and forming a malleoincudal complex. The average of morphometric parameters showed that the malleus was 3.53 ± 0.22 mm in total length. In addition to head and handle, the malleus had two distinct process; lateral and muscular. The incus had a total length 1.23 ± 0.02mm. It had long and short crus although the long crus was developed better than short crus. The lenticular bone was a round bone that articulated with the long crus of incus. The stapes had a total length 1.38 ± 0.04mm. The anterior crus(0.86 ± 0.08mm was larger than posterior crus (0.76 ± 0.08mm. It is concluded that, in the guinea pig, the malleus and the incus are fused, forming a junction called incus-malleus, while in the other animals these are separate bones. The stapes is larger and has a triangular shape and the anterior and posterior crus are thicker than other rodents. Therefore, for otological studies, the guinea pig is a good lab animal.

  17. 3-D颞骨模型的制作与应用%Manufacture and Application of Three-dimensional Prototyped Model of Temporal Bone

    Institute of Scientific and Technical Information of China (English)

    杨静雅; 田广永; 黄文华; 许靖; 吴章林; 张芳

    2015-01-01

    目的:探讨利用粉末堆积打印技术制作的高仿真3-D颞骨模型在解剖技能训练及模拟手术中的应用。方法利用高分辨率CT获取活体颞骨断层图像(正常人2例,慢性中耳炎患者2例),数据导入Mimics软件行图像分割及颞骨三维重建,以石膏粉末为原料,利用粉末堆积快速成型技术打印出颞骨模型,重要解剖结构与组织(听骨链、面神经、位听器、炎性渗出及胆脂瘤等)以不同颜色打印,并在显微镜下进行手术演练。结果颞骨模型的硬度与人骨相近,模型表面及内部骨性标志明显,解剖精确度高,钻磨触感接近真实,满足颞骨解剖技能训练及模拟手术的要求。结论利用粉末堆积打印技术能制作出仿真度更高、更接近实际人体解剖结构的颞骨模型,帮助临床医生在术前全面了解患者的颞骨及周围组织解剖结构与病变情况,制定和优化手术方案,减少并发症。%Objective The aim of this study was to investigate the temporal bone model of high precision for anatomi⁃cal skill chaining and surgery simulation by using 3-D printing technology. Methods A high-resolution computed tomogra⁃phy (CT) images were obtained from 2 normal human and 2 chronic tympanitis temporal bone . The Mimics was use for image segmentation and three-dimensional reconstruction. The temporal bone model was duplicated with Powder packing rapid pro⁃totyping technology with the material of plaster powder. The printer applied colors to the important components (like ossicular chain, facial nerve and vestibulocochlear organ ). Operational practice was performed under a microscope. Results The mate⁃rial properties were as hard as real bone. Anatomic details of the temporal bone model were dimensionally accurate and gener⁃ally comparable to the human temporal bone. Conclusion The anatomic and haptic fidelity of the temporal bone model could be manufactured by the

  18. Congenital external auditory canal atresia and stenosis: temporal bone CT findings

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Dong Hoon; Kim, Bum Soo; Jung, So Lyung; Kim, Young Joo; Chun, Ho Jong; Choi, Kyu Ho; Park, Shi Nae [College of Medicine, Catholic Univ. of Korea, Seoul (Korea, Republic of)

    2002-04-01

    To determine the computed tomographic (CT) findings of atresia and stenosis of the external auditory canal (EAC), and to describe associated abnormalities in surrounding structures. We retrospectively reviewed the axial and coronal CT images of the temporal bone in 15 patients (M:F=8:7;mean age, 15.8 years) with 16 cases of EAC atresia (unilateral n=11, bilateral n=1) and EAC stenosis (unilateral n=3). Associated abnormalities of the EAC, tympanic cavity, ossicles, mastoid air cells, eustachian tube, facial nerve course, mandibular condyle and condylar fossa, sigmoid sinus and jugular bulb, and the base of the middle cranial fossa were evaluated. Thirteen cases of bony EAC atresia (one bilateral), with an atretic bony plate, were noted, and one case of unilateral membranous atresia, in which a soft tissue the EAC. A unilateral lesion occurred more frequently on the right temporal bone (n=8, 73%). Associated abnormalities included a small tympanic cavity (n=8, 62%), decreased mastoid pneumatization (n=8, 62%), displacement of the mandibular condyle and the posterior wall of the condylar fossa (n=7, 54%), dilatation of the Eustachian tube (n=7, 54%), and inferior displacement of the temporal fossa base (n=8, 62%). Abnormalities of ossicles were noted in the malleolus (n=12, 92%), incus (n=10, 77%) and stapes (n=6, 46%). The course of the facial nerve was abnormal in four cases, and abnormality of the auditory canal was noted in one. Among three cases of EAC stenosis, ossicular aplasia was observed in one, and in another the location of the mandibular condyle and condylar fossa was abnormal. In the remaining case there was no associated abnormality. Atresia of the EAC is frequently accompanied by abnormalities of the middle ear cavity, ossicles, and adjacent structures other than the inner ear. For patients with atresia and stenosis of this canal, CT of the temporal bone is essentially helpful in evaluating these associated abnormalities.

  19. DESIR high resolution separator at GANIL, France

    Directory of Open Access Journals (Sweden)

    Toprek Dragan

    2012-01-01

    Full Text Available A high-resolution separator for the SPIRAL2/DESIR project at GANIL has been designed. The extracted isotopes from SPIRAL2 will be transported to and cooled in a RFQ cooler yielding beams with very low transverse emittance and energy spread. These beams will then be accelerated to 60 keV and sent to a high-resolution mass separator where a specific isotope will be selected. The good beam properties extracted from the RFQ cooler will allow one to obtain a mass resolution of č26000 with the high-resolution mass separator.

  20. The temporal bones from Sima de los Huesos Middle Pleistocene site (Sierra de Atapuerca, Spain). A phylogenetic approach.

    Science.gov (United States)

    Martínez, I; Arsuaga, J L

    1997-01-01

    Three well-preserved crania and 22 temporal bones were recovered from the Sima de los Huesos Middle Pleistocene site up to and including the 1994 field season. This is the largest sample of hominid temporal bones known from a single Middle Pleistocene site and it offers the chance to characterize the temporal bone morphology of an European Middle Pleistocene population and to study the phylogenetic relationships of the SH sample with other Upper and Middle Pleistocene hominids. We have carried out a cladistic analysis based on nine traits commonly used in phylogenetic analysis of Middle and Late Pleistocene hominids: shape of the temporal squama superior border, articular eminence morphology, contribution of the sphenoid bone to the median glenoid wall, postglenoid process projection, tympanic plate orientation, presence of the styloid process, mastoid process projection, digastric groove morphology and anterior mastoid tubercle. We have found two autapomorphies on the Home erectus temporal bone: strong reduction of the postglenoid process and absence of the styloid process. Modern humans, Neandertals and the Middle Pleistocene fossils from Europe and Africa constitute a clade characterized by a convex superior border of the temporal squama. The European Middle Pleistocene fossils from Sima de los Huesos, Petralona, Steinheim, Bilzingsleben and Castel di Guido share a Neandertal apomorphy: a relatively flat articular eminence. The fossils from Ehringsdorf, La Chaise Suardi and Biache-Saint-Vaast also display another Neandertal derived trait: an anteriorly obliterated digastric groove. Modern humans and the African Middle Pleistocene fossils share a synapomorphy: a sagittally orientated tympanic plate.

  1. Evaluation of haptic interfaces for simulation of drill vibration in virtual temporal bone surgery.

    Science.gov (United States)

    Ghasemloonia, Ahmad; Baxandall, Shalese; Zareinia, Kourosh; Lui, Justin T; Dort, Joseph C; Sutherland, Garnette R; Chan, Sonny

    2016-11-01

    Surgical training is evolving from an observership model towards a new paradigm that includes virtual-reality (VR) simulation. In otolaryngology, temporal bone dissection has become intimately linked with VR simulation as the complexity of anatomy demands a high level of surgeon aptitude and confidence. While an adequate 3D visualization of the surgical site is available in current simulators, the force feedback rendered during haptic interaction does not convey vibrations. This lack of vibration rendering limits the simulation fidelity of a surgical drill such as that used in temporal bone dissection. In order to develop an immersive simulation platform capable of haptic force and vibration feedback, the efficacy of hand controllers for rendering vibration in different drilling circumstances needs to be investigated. In this study, the vibration rendering ability of four different haptic hand controllers were analyzed and compared to find the best commercial haptic hand controller. A test-rig was developed to record vibrations encountered during temporal bone dissection and a software was written to render the recorded signals without adding hardware to the system. An accelerometer mounted on the end-effector of each device recorded the rendered vibration signals. The newly recorded vibration signal was compared with the input signal in both time and frequency domains by coherence and cross correlation analyses to quantitatively measure the fidelity of these devices in terms of rendering vibrotactile drilling feedback in different drilling conditions. This method can be used to assess the vibration rendering ability in VR simulation systems and selection of ideal haptic devices.

  2. Vestibular system changes in sudden deafness with and without vertigo: a human temporal bone study.

    Science.gov (United States)

    Inagaki, Taro; Cureoglu, Sebahattin; Morita, Norimasa; Terao, Kyoichi; Sato, Teruyuki; Suzuki, Mamoru; Paparella, Michael M

    2012-09-01

    To investigate the vestibular system changes in sudden deafness with vertigo (SDwV) and sudden deafness without vertigo (SDwoV) and the cause of persistent canal paresis (CP) in SDwV patients. Retrospective study. Four temporal bones from the affected ear in 4 patients with unilateral sudden deafness (SD), 2 SDwV and 2 SDwoV, were selected. Four contralateral temporal bones with normal-hearing ears were defined as the control. Morphologic findings of the labyrinth, the number of Scarpa's ganglion cells, and the density of vestibular hair cells were investigated in all temporal bones. Clinical data and the results of vestibular tests of 11 patients with unilateral SD, as a separate group, also were investigated. Atrophic change of the organ of Corti, tectorial membrane, and stria vascularis in cochlea, and deposits and atrophic otoconial membrane in vestibular sense organs were seen on affected ears more than control ears. The density of Type I hair cells seemed to decrease on the saccular macula and the posterior semicircular canal crista on affected ears, and there was no remarkable difference between SDwV and SDwoV. In 1 patient with SDwoV who died 10 months after the onset of SD, there were large amount of deposits on the cupula, the atrophied otoconial membrane was peeling off from the saccular macula, and the saccular membrane collapsed to the saccular macula in the affected ear. In the clinical data, all SDwV who were examined within 2 years from the onset had CP, and all SDwV had profound hearing loss. There is no remarkable difference between SDwV and SDwoV in the number of Scarpa's ganglion cells and the density of vestibular hair cells. The damage of the extracellular superstructure is seen in SD with or without vertigo. The damage of extracellular superstructure is potentially one of the causes of persistent CP in patients with SD.

  3. Three dimensional CT of stapes. Stapedial imagings in dry temporal bone and clinical applications

    Energy Technology Data Exchange (ETDEWEB)

    Edamatsu, Hideo; Kubota, Osamu; Yamashita, Koichi [Kanazawa Medical Univ., Ishikawa (Japan)

    1995-03-01

    This study was performed to evaluate the usefulness and limitations of three dimensional (3-D) imagings of stapes in the middle ear by high speed helical CT. One dissected human temporal bone, ten normal and diseased ears were scanned with a slice of 1.0 mm and reconstructed in a thickness of 0.2-0.5 mm. Every specimen of 3-D can be observed in any plane and from any direction. Ossicular imagings of the temporal bone in 3-D were reconstructed as if the malleus, incus and stapes were observed under microscope. The whole structure of stapes was impossible to be represented by two dimensional CT heretofore in use, but 3-D in our study showed the head, crus and foot plate of the stapes in detail. Stapedial imagings of 3-D CT in normal ears showed the same findings as those recorded in temporal bone. Preoperative diagnostic findings of ossicles in the affected ears were very useful. Especially in ossicular anomalies, 3-D CT was positive in diagnosis and its accuracies were confirmed with operative observation. For the postoperative evaluation concerning the ossicular reconstruction, i.e. TORP and PORP, 3-D CT was also important method. It could present an anatomical relation between those prosthesis and the oval window. High speed helical CT can scan an object more quickly and clearly than formerly used CT, and its biological damage for human is less than that of the others. 3-D CT can be more clearly reconstructed with helical CT than former CT. (author).

  4. Temporal bone histopathology in trisomy 18 syndrome: a report of two cases.

    Directory of Open Access Journals (Sweden)

    Saito,Ryusuke

    1987-06-01

    Full Text Available Temporal bone histopathological findings of two patients with trisomy 18 syndrome are described. Many of the abnormalities previously described were seen in the present cases; namely, atresia of the external auditory canal, aberrant course of the tensor tympani muscle, malformed stapes, aberrant course of the facial nerve with an obtuse angulation at the first genu and displacement of geniculate ganglion cells into the internal auditory canal, shortened cochlea with decreased spiral ganglion cell population, and vestibular anomalies, such as bony and membranous blockage of the superior semicircular canal. Moreover, an extremely underdeveloped malleus and incus continuous with a persistent Meckel's cartilage were observed.

  5. Infantile desmoid-type fibromatosis with involvement of temporal bone: case report

    Energy Technology Data Exchange (ETDEWEB)

    Hagen, T. [Dept. of Neuroradiology, Saarland Univ., Homburg (Germany); Feiden, W. [Dept. of Neuropathology, Saarland Univ., Homburg (Germany); Piepgras, U. [Dept. of Neuroradiology, Saarland Univ., Homburg (Germany)

    1995-12-31

    Infantile desmoid-type fibromatosis is a rare, benign, infiltratively growing tumor of the soft tissue. The histological classification is often confusing due to various patterns. Although surgical excision is the treatment of choice, local recurrence is high. Ultrasound, CT, and MRI cannot differentiate the different types of fibrous lesions, but are very essential, showing the localization and infiltrated tissues. We report an unusual case of desmoid-type fibromatosis destroying the temporal bone in a now-5-year-old boy. The literature contains only few reports of radiological findings in patients with infantile fibromatosis. (orig.)

  6. [Glomus tumors of the temporal bone: a report of 6 cases].

    Science.gov (United States)

    Arruda, W O; Teive, H A; Torres, L F; Ramina, R; Parolim, M K; Maniglia, J J; Barrionuevo, C E

    1989-03-01

    The authors review the clinical, radiological and pathological features of 6 cases of glomus tumors of the temporal bone. Out of the 6 patients, 5 were female; age was distributed between 22 and 76 years (mean 48 years). The main clinical features were hypoacusia, tinnitus and otoscopic findings suggestive of the diagnosis. In one case was noted the concomitant presence of a neurinoma of the VIII cranial nerve with a ipsilateral glomus tumor, and in another case there was a concomitancy of carotid body tumor with temporal glomus jugularis tumor. Metastases were not observed in any case. Tumoral lesions were successfully ressected employing microsurgical techniques and a multidisciplinary staff involving neurosurgeons, head and neck surgeons and otolaryngologists. Radioteraphy was not employed, neither pre-operative embolization. Some aspects related to the nosology, embriology, pathophysiology, diagnosis and treatment of this interesting type of neoplasms are discussed.

  7. High Resolution Silicon Deformable Mirrors Project

    Data.gov (United States)

    National Aeronautics and Space Administration — This proposal describes a plan to build a prototype small stroke, high precision deformable mirror suitable for space-based operation in systems for high-resolution...

  8. High Resolution Silicon Deformable Mirrors Project

    Data.gov (United States)

    National Aeronautics and Space Administration — In this proposal we describe a plan to build a deformable mirror suitable for space-based operation in systems for high-resolution imaging. The prototype DM will be...

  9. VT Hydrography Dataset - High Resolution NHD

    Data.gov (United States)

    Vermont Center for Geographic Information — (Link to Metadata) The Vermont Hydrography Dataset (VHD) is compliant with the local resolution (also known as High Resolution) National Hydrography Dataset (NHD)...

  10. High-resolution neutron microtomography with noiseless neutron counting detector

    Energy Technology Data Exchange (ETDEWEB)

    Tremsin, A.S., E-mail: ast@ssl.berkeley.edu [Space Sciences Laboratory, University of California, Berkeley, CA 94720 (United States); McPhate, J.B.; Vallerga, J.V.; Siegmund, O.H.W. [Space Sciences Laboratory, University of California, Berkeley, CA 94720 (United States); Feller, W.B. [Nova Scientific Inc., 10 Picker Road, Sturbridge, MA 01566 (United States); Lehmann, E. [Paul Scherrer Institute, CH-5232 Villigen (Switzerland); Butler, L.G. [Louisiana State University, Baton Rouge, LA 70803 (United States); Dawson, M. [Helmholtz Centre Berlin for Materials and Energy (Germany)

    2011-10-01

    The improved collimation and intensity of thermal and cold neutron beamlines combined with recent advances in neutron imaging devices enable high-resolution neutron radiography and microtomography, which can provide information on the internal structure of objects not achievable with conventional X-ray imaging techniques. Neutron detection efficiency, spatial and temporal resolution (important for the studies of dynamic processes) and low background count rate are among the crucial parameters defining the quality of radiographic images and tomographic reconstructions. The unique capabilities of neutron counting detectors with neutron-sensitive microchannel plates (MCPs) and with Timepix CMOS readouts providing high neutron detection efficiency ({approx}70% for cold neutrons), spatial resolutions ranging from 15 to 55 {mu}m and a temporal resolution of {approx}1 {mu}s-combined with the virtual absence of readout noise-make these devices very attractive for high-resolution microtomography. In this paper we demonstrate the capabilities of an MCP-Timepix detection system applied to microtomographic imaging, performed at the ICON cold neutron facility of the Paul Scherrer Institute. The high resolution and the absence of readout noise enable accurate reconstruction of texture in a relatively opaque wood sample, differentiation of internal tissues of a fly and imaging of individual {approx}400 {mu}m grains in an organic powder encapsulated in a {approx}700 {mu}m thick metal casing.

  11. Structure of high-resolution NMR spectra

    CERN Document Server

    Corio, PL

    2012-01-01

    Structure of High-Resolution NMR Spectra provides the principles, theories, and mathematical and physical concepts of high-resolution nuclear magnetic resonance spectra.The book presents the elementary theory of magnetic resonance; the quantum mechanical theory of angular momentum; the general theory of steady state spectra; and multiple quantum transitions, double resonance and spin echo experiments.Physicists, chemists, and researchers will find the book a valuable reference text.

  12. Differential diagnosis between chronic otitis media with and without cholesteatoma by temporal bone CT: focus on bone change and mass effect

    Energy Technology Data Exchange (ETDEWEB)

    Jung, Cheol Kyu; Park, Dong Woo; Seong, Jin Yong; Lee, Kak Soo; Park Choong Ki; Lee, Seung Ro; Hahm, Chang Kok [College of Medicine, Hanyang University, Seoul (Korea, Republic of)

    2000-01-01

    In order to determine specific differences, we compared the temporal bone CT findings of chronic otitis media (COM) with and without cholesteatoma, focusing on bone change. Between 1997 and 1998, 82 patients (84 cases) underwent temporal bone CT and were shown to have COM, with or without cholesteatoma after mastoidectomy and tympanoplasty. There were 36 cases of COM with cholesteatoma (26 patients, M:F =3D 11:15; age range, 16-61 (mean, 36,2) years), and 58 cases without chlesteatoma (56 patients, M:F =3D 25:31, age range, 15-61 (mean, 36.2) years). The findings of temporal bone CT were analysed at the point of bony changes including erosion and medial displacement of ossicles (malleus, incus, and stapes), erosion or destruction of the scutum, tegmen, facial canal, and lateral semicircular canal, and ballooning of the tympanic cavity and mastoid antrum. In addition, the soft tissue changes seen on temporal bone CT were analyzed at the site of lateral bulging of soft tissue in Prussak's space, perforation of the pars flaccida, tympanic membrane retraction, and tympanosclerosis. We retrospectively compared the findings of temporal bone CT with the surgical findings, and to assess statistical significance, the Chi-square test was used. Bone erosion or destruction was seen in 36.2% of COM cases without cholesteatoma, and in 96.2% of cases with cholesteatoma. Comparing COM with and without cholesteatoma, the erosion of ossicles including the malleus (81%, 24%), incus (88%, 14%), stapes (58%, 10%), scutum (88%, 10%), facial canal (8%, 0%), and lateral semicircular canal (8%, 0%), was more common in COM with cholesteatoma (p-value less than 0.05), with the exception of erosion of the tegmen (8%, 3%). Other bony changes including medial displacement of ossicles (27%, 3%), ballooning of tympanic cavity and mastoid antrum (96%, 16%), and the soft tissue changes including lateral bulging of soft tissue in Prussak's space (58%, 14%) and perforation of the pars

  13. SUBJECTIVE TINNITUS AS FIRST PRESENTATION IN A PATIENT WITH METASTATIC LUNG CANCER IN TEMPORAL BONE-A CASE REPORT

    Institute of Scientific and Technical Information of China (English)

    ZHANG Jing; WANG Hongtian; JIA Jingjie; XIAO Yueyong; SHI Huaiyin; YANG Weiyan

    2013-01-01

    Metastasis of lung cancer to the temporal bone is a very rare disease and subjective tinnitus as the present-ing symptom in these patients is even rarer. Here we report a case in which a 42-year-old male presented with subjective tinnitus of three months, with no pulmonary disease symptoms. Pure tone audiometry indi-cated moderate conductive deafness in left ear with an air-bone gap of 21.3 dB. HRCT temporal bone scan-ning indicated high-density shadows in the left epitympanic cavity, sinus tympani and mastoid cavity. Chron-ic otitis media with cholesteatoma was suspected and surgical treatment recommended. However, preopera-tive chest x-ray revealed high-density millet lesions scattered widely in both lungs. HRCT lung scanning confirmed the lungs lesions and indicated lung cancer. In order to determine correlations between the tempo-ral bone and pulmonary lesions, a CT-guided trans-mastoid aspiration biopsy and immunohistochemical study were conducted, which confirmed that the temporal bone lesion was metastatic from the lungs. The pa-tient was given a series of chemotherapy immediately and his tinnitus significantly improved after three months of treatment, with full recovery of his hearing and complete resolution of shadows in the mastoid cavity. Unfortunately, he subsequently developed multiple bone metastases in the 9th month and cerebral metastasis in the 18th month. Multiple organ failure resulted in death in 2.5 years.

  14. Histomorphometric analysis of the temporal bone after change of direction of force vector of mandible: an experimental study in rabbits

    Directory of Open Access Journals (Sweden)

    Edela Puricelli

    2012-10-01

    Full Text Available OBJECTIVES: The present study aimed at performing a histological evaluation of the response of temporal bone tissue to a change of direction of the force vector of the mandible in relation to the base of the skull. MATERIAL AND METHODS: Adult rabbits were assigned into four groups with two control and four experimental animals in each group. experimental animals underwent surgery, which resulted in a change of direction of the force vector on the right temporomandibular joint. Samples were collected after 15, 30, 60 and 90 days for histological analysis. RESULTS: In the two-way analysis of variance, the effect of group and time was statistically significant (p<0.001. Additionally, a statistically significant interaction between group and time was observed (p<0.001. Control animals showed normal growth and development of the temporal region. In the experimental group, the change in direction of the force vector of the mandible induced significant changes in the temporal bone, with a bone modeling process, which suggests growth of this cranial structure. CONCLUSIONS: The methodology used in this experiment allows us to conclude that the change in direction of the force vector of the mandible in relation to the skull base induces remodeling and modeling processes in the temporal bone. The resumption of normal oral functions after bone healing of the mandibular fracture appears to increase cell activation in the remodeling and modeling of the temporal bone structure. The observation of areas of temporal bone modeling shows the relevance of further investigation on the correlation between the joint structures and craniofacial growth and development.

  15. Familial dysautonomia (Riley-Day syndrome). Temporal bone findings and otolaryngological manifestations.

    Science.gov (United States)

    Tokita, N; Sekhar, H K; Sachs, M; Daly, J F

    1978-01-01

    Familial dysautonomia, or Riley-Day syndrome, is inherited in an autosomal recessive fashion and occurs almost exclusively in Jewish families. This disorder is characterized by a smooth tongue devoid of fungiform papillae and of taste buds, and is clinically associated with poor taste discrimination. An unsteady gait and dizziness on change in position are also common presenting symptoms. This study reports the histopathological findings of eight temporal bones from four patients with documented familial dysautonomia. For the control series, 13 normal temporal bones were also studied. The most striking finding in the dysautonomic patients was an extreme paucity of geniculate ganglion cells (P less than 0.001). A statistically significant reduction in the number of neurons was also found both in the superior and in the inferior divisions of the vestibular nerve (P less than 0.001). The paucity of the geniculate ganglion cells correlates well with the impairment of the taste in dysautonomic individuals, since the afferent fibers leaving taste buds of the anterior two-thirds of the tongue run via the chorda tympani and have their cell bodies in the geniculate ganglion. Furthermore, the reduction in the number of Scarpa's ganglion cells observed in the dysautonomic patients studied here could account for a poor response to caloric test, positional vertigo and an unsteady gait in this condition.

  16. Displasia fibrosa do osso temporal: relato de caso e revisão da literatura Fibrous dysplasia of the temporal bone: case report and review of the literature

    Directory of Open Access Journals (Sweden)

    Vanier S. Júnior

    2004-12-01

    Full Text Available Displasia fibrosa é uma doença caracterizada por progressiva substituição dos elementos normais do osso por tecido fibroso. É uma patologia benigna incomum de etiologia desconhecida. Existem duas categorias primárias da doença: displasia fibrosa monostótica que envolve somente um osso e displasia fibrosa poliostótica acometendo múltiplos ossos. Embora o esqueleto crânio-facial seja sede freqüente da doença, o osso temporal raramente está envolvido. O envolvimento do osso temporal tem como sintoma mais comum a surdez. O diagnóstico é baseado em imagens radiológicas. Quando a displasia fibrosa é acompanhada por sintomas clínicos significantes, o tratamento cirúrgico é recomendado. O acompanhamento clínico do paciente é fundamental para o diagnóstico precoce de recidivas. Neste artigo relatamos um caso de displasia fibrosa do osso temporal e revisão da patologia na literatura.Fibrous dysplasia is a disease characterized by progressive replacement of normal bone elements by fibrous tissue. It is an uncommon benign disorder of unknown etiology. There are two primary categories of the disease: monostotic fibrous dysplasia that involves a single bone and polyostotic fibrous dysplasia that involves multiple bones. Although the craniofacial skeleton is a common site of the disease, the temporal bone rarely becomes involved. The most common presenting symptom is deafness and diagnosis is based on radiological images. When fibrous dysplasia is accompanied by significant clinical symptoms, surgery is recommended. The follow up of these patients is very important to make early diagnosis of recurrences. In this article we report a case of fibrous dysplasia of the temporal bone and review the literature.

  17. Improving Depiction of Temporal Bone Anatomy With Low-Radiation Dose CT by an Integrated Circuit Detector in Pediatric Patients

    Science.gov (United States)

    He, Jingzhen; Zu, Yuliang; Wang, Qing; Ma, Xiangxing

    2014-01-01

    Abstract The purpose of this study was to determine the performance of low-dose computed tomography (CT) scanning with integrated circuit (IC) detector in defining fine structures of temporal bone in children by comparing with the conventional detector. The study was performed with the approval of our institutional review board and the patients’ anonymity was maintained. A total of 86 children  0.05). The low-dose CT images acquired with the IC detector provide better depiction of fine osseous structures of temporal bone than that with the conventional DC detector. PMID:25526489

  18. Pneumatization of the zygomatic process of temporal bone on computed tomograms

    Directory of Open Access Journals (Sweden)

    Friedrich, Reinhard E.

    2016-06-01

    Full Text Available Purpose: Zygomatic air cells (ZAC are a variant of temporal bone pneumatization that needs no treatment. However, ZAC can have an impact on surgical procedures in the temporo-mandibular joint region. Recent reports suggest that computed tomography will disclose more ZAC than can be diagnosed on panoramic radiography. The aim of this study was to analyze ZAC prevalence on CT in a population that was not pre-selected by admission to a dental clinic. Furthermore, an extensive literature review was performed to assess the prevalence of ZAC and to address the impact of imaging technique on the definition of the item.Material and methods: Digitalized cranial CTs of 2007 patients were retrospectively analyzed. The Frankfort horizontal was used to define a ZAC on sagittal CTs. Results: In this study group, 806 were female (40.16% and 1,201 were male (59.84%. Mean age was 49.96 years in the whole group (female: 55.83 years, male: 46.01 years. A ZAC was diagnosed in 152 patients (female: 66, male: 86. Unilateral ZAC surpasses bilateral findings (115 vs. 37 patients. ZAC were diagnosed in children 5 years of age and older. Sectional imaging techniques show a better visualization of the region of interest. However, presently an increase of ZAC prevalence attributable to imaging technique cannot conclusively be derived from the current literature. The normal finding of a ZAC on radiograms is a sharply defined homogenous transparent lesion restricted to the zygomatic process of the temporal bone that has no volume effect on the shape of the process.Conclusion: ZAC is an anatomical variant of the temporal bone that has come into focus of maxillofacial radiology due to its noticeable aspect on panoramic radiograms. The harmless variant can be expected in about one in thirteen individuals undergoing facial radiology. Panoramic radiograms appear to be sufficient to present ZAC of relevant size. However, in preparation for surgical procedures affecting the

  19. High resolution full-spectrum water Raman lidar

    Institute of Scientific and Technical Information of China (English)

    LIU FuChao; YI Fan; JIA JingYu; ZHANG YunPeng; ZHANG ShaoDong; YU ChangMing; TAN Ying

    2012-01-01

    Knowledge of the temporal-spatial distribution of water content in atmosphere and water phase change in cloud is important for atmospheric study.For this purpose,we have developed a high resolution full-spectrum water Raman lidar that can collect Raman signals from ice,water droplets and water vapor simultaneously.A double-grating polychromator and a 32-channel photomultiplier-tube detector are used to obtain a spectral resolution of ~0.19 nm in the full Raman spectrum range of water.Preliminary observations present the water Raman spectrum characteristics of both the mixed-phase cloud and humid air under cloudless condition.

  20. Decolonizing Straight Temporality Through Genre Trouble in Edwidge Danticat's The Farming of Bones

    Directory of Open Access Journals (Sweden)

    Eliana de Souza Ávila

    2014-12-01

    Full Text Available http://dx.doi.org/10.5007/2175-8026.2014n67p21 Framing genre trouble (McKenzie 2006 as a decolonial methodology, this paper considers the relevance of Edwidge Danticat’s The Farming of Bones (1998 for reading migrant texts against the grain of straight temporality which sustains the coloniality of power (Lugones 2007. Scrutinizing historiographic suppression, Danticat’s migrant text interrupts the chrononormative portrayal of the Trujillo genocide of Haitian workers in the Dominican Republic as a reality pertaining to an obsolete past and to the geocultural margins alone. Read in the aftermath of the testimonio controversy, it may thus decenter the ongoing deflection of attention from Rigoberta Menchú’s impact on the geocultural structures that sanction ongoing military intervention and genocide by refocusing on historiography as a terrain of relentless decolonial contestation rather than prescriptive narrative closure.

  1. Eosinophilic granuloma of the temporal bone- its clinical manifestations and management

    Directory of Open Access Journals (Sweden)

    Kirtane Jyotsna

    1978-01-01

    Full Text Available Eosinophilic granuloma is a variety of Histiocytosis-X. Its etio-logy is unknown. When it involves the temporal bone it may mimic chronic otitis media, or a mastoid abscess, very often leading to an erroneous diagnosis. Its X-ray appearance and histopathology are characteristic. Infiltration with eosinophils and histiocytes is a constant feature. Very good results are achieved with surgery accompanied by radiotherapy. In this series of 3 patients, one pa-tient presented with facial paralysis and another one with bilateral post-auricular swellings. The first 2 cases were diagnosed only after surgery and histopathological examination of the tissue removed, while the third case was diagnosed pre-operatively on clinical and radiological findings.

  2. Clinical and experimental study on facial paralysis in temporal bone fracture

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    Objective: To study the main prognostic factors and significanceof facial nerve decompression for facial paralysis in temporal bone fracture.Methods: The main relative prognostic factors of 64 patients with facial paralysis were analyzed. An experimental model of facial paralysis was made. The expansion rates of facial nerve in the facial canal opening group and the facial canal non-opening group were measured and observed under electron microscope.Results: The main factors affecting the prognosis were facial nerve decompression and selection of surgery time. The expansion rate of facial nerve in the facial canal opening group was significantly higher than that of the facial canal non-opening group (t=7.53, P<0.01). The injury degree of the nerve fiber in the facial canal non-opening group was severe.Conclusions: Early facial nerve decompression is beneficial to restoration of the facial nerve function.

  3. Concurrent necrotising otitis externa and adenocarcinoma of the temporal bone: a diagnostic challenge.

    Science.gov (United States)

    Foden, Neil; Burgess, Christopher; Damato, Stephen; Ramsden, James

    2013-11-06

    We present a case of an 81-year-old man who was diagnosed with a necrotising (malignant) otitis externa (NOE). Initial biopsies from the external auditory canal showed scanty squamous epithelium but no evidence of malignancy. Despite an initial improvement on intravenous antibiotics and subsequent discharge from hospital, the patient returned with worsening otalgia. Following readmission to the hospital, intravenous antibiotics were restarted. Despite this, the patient developed a lower motor neurone palsy of cranial nerve VII on the ipsilateral side of the pain. He was taken to the theatre for an exploration of the left mastoid with further biopsies. Adenocarcinoma was diagnosed histologically and the patient was started on palliative radiotherapy. This case adds to the known literature on metastatic disease in the temporal bone and highlights the need to exclude malignancy in cases of NOE.

  4. High-resolution Imaging Techniques for the Assessment of Osteoporosis

    Science.gov (United States)

    Krug, Roland; Burghardt, Andrew J.; Majumdar, Sharmila; Link, Thomas M.

    2010-01-01

    Synopsis The importance of assessing the bone’s microarchitectural make-up in addition to its mineral density in the context of osteoporosis has been emphasized in a number of publications. The high spatial resolution required to resolve the bone’s microstructure in a clinically feasible scan time is challenging. Currently, the best suited modalities meeting these requirements in vivo are high-resolution peripheral quantitative imaging (HR-pQCT) and magnetic resonance imaging (MRI). Whereas HR-pQCT is limited to peripheral skeleton regions like the wrist and ankle, MRI can also image other sites like the proximal femur but usually with lower spatial resolution. In addition Multidetector-CT has been used for high-resolution imaging of trabecular bone structure, however, the radiation dose is a limiting factor. This article provides an overview of the different modalities, technical requirements and recent developments in this emerging field. Details regarding imaging protocols as well as image post-processing methods for bone structure quantification are discussed. PMID:20609895

  5. 3D-CT of the temporal bone area with high-speed processing

    Energy Technology Data Exchange (ETDEWEB)

    Hattori, Taku [Nagoya Univ. (Japan). Branch Hospital

    1994-12-01

    Three-dimentional (3D)-CT was introduced to represent abnormal findings in the temporal bone area utilizing a SOMATOM DRH CT scanner with accessory 3D reconstruction software and an exclusive high-speed 3D processing system, VOXEL FLINGER. In a patient with eosinophilic granuloma, a defect in the squamous part of the temporal bone was demonstrated suggesting exposure of the dura mater during surgery. In a patient with a normal ear, well-developed mastoid cavity, a part of the handle and the head of the malleus, the incudomalleal joint, the short limb, body and a part of the long limb of the incus and the round window niche were demonstrated. In a case of chronic otitis media, poorly developed mastoid cavity and a possible defect of the tip of the long limb of the incus were demonstrated, in contrast to the patient with the normal ear. 3D-CT yields objective and solid images which are useful for diagnosis, treatment planning and explanation of the pathology to patients and their family. To obtain convincing 3D images, physicians themselves have to choose exact rotation angles. It is not adequate to reconstruct original CT data using a CT computer with accessory 3D software whose processing capability is not good enough for this purpose. The conclusion is as follows: (1) it is necessary and effective to transfer original CT data into the memory of the exclusive high-speed 3D processing system and (2) process the data by the voxel memory method to establish a clinically valuable 3D-CT imaging system. (author).

  6. Temporal bone trauma: correlative study between CT findings and clinical manifestations

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Jung Hee; Kim, Hyung Jin; Kim, Jae Hyoung [College of Medicine, Gyeongsang National University, Jinju (Korea, Republic of)

    1994-11-15

    To assess how accurately computed tomography (CT) can demonstrate the abnormal findings which are believed to cause the clinical signs and symptoms of hearing loss (HL), vertigo and facial paralysis (FP) in patients with temporal bone trauma. The authors studied CT scans of 39 ears in 35 patients with temporal bone trauma. CT scans were performed with 1-1.5 mm slice thickness and table incrementation. Both axial and coronal scans were obtained in 32 patients and in three patients only axial scans were obtained. We analyzed CT with special reference to the structural abnormalities of the external auditory canal, middle ear cavity, bony labyrinth, and facial nerve canal, and correlated these findings with the actual clinical signs and symptoms. As to hearing loss, we evaluated 32 ears in which pure tone audiometry or brainstem evoked response audiometry had been performed. With respect to the specific types of HL, CT accurately showed the abnormalities in 84% (16/19) in conductive HL, 100% (2/2) in sensorineural HL, and 25% (2/8) for mixed HL. When we categorized HL simply as conductive and sensorineural, assuming that mixed be the result of combined conductive and sensorineural HL, CT demonstrated the abnormalities in 89% (24/27) for conductive HL and 50% (5/10) for sensorineural HL. Concerning vertigo and FP, CT demonstrated abnormalities in 67%(4/6), and 29% (4/14), respectively. Except for conductive HL, CT seems to have a variable degree of limitation for the demonstration of the structural abnormalities resulting sensorineural HL, vertigo or facial paralysis. It is imperative to correlate the CT findings with the signs and symptoms in those clinical settings.

  7. The future of high resolution electron microscopy

    Institute of Scientific and Technical Information of China (English)

    D Van Dyck

    2000-01-01

    The state of the art and the future in quantitative high resolution electron microscopy are discussed in the framework of parameter estimation. Reconstruction methods are then to be considered as direct methods to yield a starting structure for further refinement. With the increasing flexibility of the instruments, computer aided experimental strategy will become important.

  8. High resolution spectroscopy of planet bearing stars

    Directory of Open Access Journals (Sweden)

    M. C. Gálvez

    2007-01-01

    Full Text Available We present here the first steps of an extended spectroscopic survey in order to characterize the stellar hosts of extra-solar planets. We have selected several known stars with plan- ets and using high resolution spectroscopy, we have studied their properties.

  9. High-resolution seismic profiling on water

    OpenAIRE

    McGee, T.M.

    2000-01-01

    Herein is presented an overview of high-resolution seismic profiling on water. Included are basic concepts and terminology as well as discussions of types of sources and receivers, field practice, data recording and data processing. Emphasis is on digital single-channel profiling for engineering and environmental purposes.

  10. Compact high-resolution spectral phase shaper

    NARCIS (Netherlands)

    Postma, S.; Walle, van der P.; Offerhaus, H.L.; Hulst, van N.F.

    2005-01-01

    The design and operation of a high-resolution spectral phase shaper with a footprint of only 7×10 cm2 is presented. The liquid-crystal modulator has 4096 elements. More than 600 independent degrees of freedom can be positioned with a relative accuracy of 1 pixel. The spectral shaping of pulses fro

  11. A High-Resolution Stopwatch for Cents

    Science.gov (United States)

    Gingl, Z.; Kopasz, K.

    2011-01-01

    A very low-cost, easy-to-make stopwatch is presented to support various experiments in mechanics. The high-resolution stopwatch is based on two photodetectors connected directly to the microphone input of a sound card. Dedicated free open-source software has been developed and made available to download. The efficiency is demonstrated by a free…

  12. Compressive sensing for high resolution radar imaging

    NARCIS (Netherlands)

    Anitori, L.; Otten, M.P.G.; Hoogeboom, P.

    2010-01-01

    In this paper we present some preliminary results on the application of Compressive Sensing (CS) to high resolution radar imaging. CS is a recently developed theory which allows reconstruction of sparse signals with a number of measurements much lower than what is required by the Shannon sampling th

  13. Sensorineural hearing loss: there is no correlation with isolated dysplasia of the lateral semi-circular canal on temporal bone CT

    Energy Technology Data Exchange (ETDEWEB)

    Yamashita, Koji; Yoshiura, Takashi; Hiwatashi, Akio; Tuvshinjargal, Dashjamts; Kamano, Hironori; Honda, Hiroshi (Dept. of Clinical Radiology, Graduate School of Medical Sciences, Kyushu Univ. Fukuoka (Japan)), email: tyoshiu@radiol.med.kyushu-u.ac.jp; Inoguchi, Takashi (Dept. of Otolaryngology, Kitakyushu Municipal Medical Center, Kitakyushu (Japan))

    2011-02-15

    Background: Inner ear malformations may cause sensorineural hearing loss (SNHL). However, the correlation between the small lateral semi-circular canal (LSCC) and SNHL is controversial. Purpose: To determine whether there is a correlation between the two using CT-based measurement. Material and Methods: We retrospectively reviewed the high-resolution CT images of the temporal bone obtained from consecutive patients. A total 136 ears of 68 patients (25 men and 43 women; age range 20-85 years, mean 49.8 years) were included in this study. Patients who were clinically suspected to have otosclerosis were also excluded. Two radiologists independently measured the width and cross-sectional area of the bony island of LSCC. We evaluated the correlation between LSCC bone island width or cross-sectional area and hearing level in all cases using Pearson correlation co-efficients. In addition, we compared hearing levels among the patient group with normal-sized LSCC (>=mean-SD), small LSCC (0.05). No significant difference in hearing levels were found among groups of the normal-sized, small and very small LSCC (P>0.05). Conclusion: We conclude that there is no correlation between isolated small LSCC and SNHL

  14. Giant cell granuloma of the temporal bone in a mixed martial arts fighter.

    Science.gov (United States)

    Maerki, Jennifer; Riddle, Nicole D; Newman, Jason; Husson, Michael A; Lee, John Y K

    2012-10-01

    Background and Importance Giant cell granuloma (GCG) is a rare, benign, non-neoplastic lesion of the head and neck. More common in the jaw bones, there have been few reports of the lesion arising in the temporal bone. Initially referred to as a "giant cell reparative granuloma," due to the previously accepted notion of its nature in attempting to repair areas of injury, the term "giant cell granuloma" is now more frequently used as this lesion has been found in patients without a history of trauma. In addition, several cases with a destructive nature, in contrast to a reparative one, have been observed. Clinical Presentation We report a case of GCG presenting as a head and neck tumor with dural attachments and extension into the middle cranial fossa in a mixed martial arts fighter. Conclusion Giant cell granulomas are typically treated surgically and have a good prognosis; however, care must be taken when they present in unusual locations. This case supports the theory of trauma and inflammation as risk factors for GCG.

  15. Multi-temporal MRI carpal bone volumes analysis by principal axes registration

    Science.gov (United States)

    Ferretti, Roberta; Dellepiane, Silvana

    2016-03-01

    In this paper, a principal axes registration technique is presented, with the relevant application to segmented volumes. The purpose of the proposed registration is to compare multi-temporal volumes of carpal bones from Magnetic Resonance Imaging (MRI) acquisitions. Starting from the study of the second-order moment matrix, the eigenvectors are calculated to allow the rotation of volumes with respect to reference axes. Then the volumes are spatially translated to become perfectly overlapped. A quantitative evaluation of the results obtained is carried out by computing classical indices from the confusion matrix, which depict similarity measures between the volumes of the same organ as extracted from MRI acquisitions executed at different moments. Within the medical field, the way a registration can be used to compare multi-temporal images is of great interest, since it provides the physician with a tool which allows a visual monitoring of a disease evolution. The segmentation method used herein is based on the graph theory and is a robust, unsupervised and parameters independent method. Patients affected by rheumatic diseases have been considered.

  16. Analysis of Vibrant Soundbridge placement against the round window membrane in a human cadaveric temporal bone model.

    NARCIS (Netherlands)

    Pennings, R.J.E.; Ho, A.; Brown, J.; Wijhe, R.G. van; Bance, M.

    2010-01-01

    OBJECTIVE: To evaluate optimal placement of the Floating Mass Transducer of the Vibrant Soundbridge (Med-El, Innsbruck, Austria) against the round window membrane, particularly the impact of interposed coupling fascia and of covering materials. METHOD: : Six fresh human cadaveric temporal bones were

  17. Systemic Lupus Erythematosus and hearing disorders: Literature review and meta-analysis of clinical and temporal bone findings.

    Science.gov (United States)

    Di Stadio, Arianna; Ralli, Massimo

    2017-01-01

    Objective This literature review and meta-analysis was performed to evaluate the correlations among hearing and vestibular clinical symptoms, temporal bone findings, and pathological mechanisms in patients with systemic lupus erythematosus (SLE). Study design Relevant papers in the literature were retrospectively reviewed. Clinical hearing aspects in patients with SLE and relevant temporal bone studies in the same field were analyzed. Methods PubMed and Google Scholar searches were performed using the following keywords: "auto-immune disease," "systemic lupus erythematosus (SLE)," "hearing loss," "temporal bone study," "vertigo," "dizziness," "tinnitus," "ear symptoms," "treatment," "diagnosis," "symptoms," "etiopathogenesis," "Wegener granulomatosis," "Sjogren," "polyarteritis nodosa," "Cogan syndrome," and "granulomatosis." Also included were reviews in which the following terms were present: "SLE," "temporal bone," and "hearing symptoms." Review and conclusion This literature review and meta-analysis focused on the pathological mechanisms through which SLE can damage inner ear structures and determinate hearing and vestibular symptoms. The main mechanisms involved in inner ear damage include the autoimmune response, deposition of immune complexes in the vessels and, to a lesser extent, cytotoxic damage.

  18. Cochlear Implantation through the Middle Fossa Approach: A Review of Related Temporal Bone Studies and Reported Cases.

    Science.gov (United States)

    Lesser, Juan Carlos Cisneros; Brito Neto, Rubens Vuono de; Martins, Graziela de Souza Queiroz; Bento, Ricardo Ferreira

    2017-01-01

    Introduction Middle fossa approach has been suggested as an alternative for patients in whom other routes of electrode insertion are contraindicated. Even though there are temporal bone studies about the feasibility of introducing the cochlear implant through the middle fossa, until now, very few studies have described results when cochlear implant surgery is done through this approach. Objective The objective of this study is to review a series of temporal bone studies related to cochlear implantation through the middle fossa and the results obtained by different surgical groups after cochlear implantation through this approach. Data Sources PubMed, MD consult and Ovid-SP databases. Data Synthesis A total of 8 human cadaveric temporal bone studies and 6 studies reporting cochlear implant surgery through the middle fossa approach met the inclusion criteria. Temporal bone studies show that it is feasible to perform cochlear implantation through this route. So far, only two surgical groups have performed cochlear implantation through the middle fossa with a total of 15 implanted patients. One group entered the cochlea in the most upper part of the basal turn, inserting the implant in the direction of the middle and apical turns; meanwhile, the other group inserted the implant in the apical turn directed in a retrograde fashion to the middle and basal turns. Results obtained in both groups were similar. Conclusions The middle fossa approach is a good alternative for cochlear implantation when other routes of electrode insertion are contraindicated.

  19. Analysis of Vibrant Soundbridge placement against the round window membrane in a human cadaveric temporal bone model.

    NARCIS (Netherlands)

    Pennings, R.J.E.; Ho, A.; Brown, J.; Wijhe, R.G. van; Bance, M.

    2010-01-01

    OBJECTIVE: To evaluate optimal placement of the Floating Mass Transducer of the Vibrant Soundbridge (Med-El, Innsbruck, Austria) against the round window membrane, particularly the impact of interposed coupling fascia and of covering materials. METHOD: : Six fresh human cadaveric temporal bones were

  20. Dual-time-point FDG-PET/CT Imaging of Temporal Bone Chondroblastoma: A Report of Two Cases.

    Science.gov (United States)

    Toriihara, Akira; Tsunoda, Atsunobu; Takemoto, Akira; Kubota, Kazunori; Machida, Youichi; Tateishi, Ukihide

    2015-01-01

    Temporal bone chondroblastoma is an extremely rare benign bone tumor. We encountered two cases showing similar imaging findings on computed tomography (CT), magnetic resonance imaging (MRI), and dual-time-point (18)F-fluorodeoxyglucose ((18)F-FDG) positron emission tomography (PET)/CT. In both cases, CT images revealed temporal bone defects and sclerotic changes around the tumor. Most parts of the tumor showed low signal intensity on T2-weighted MRI images and non-uniform enhancement on gadolinium contrast-enhanced T1-weighted images. No increase in signal intensity was noted in diffusion-weighted images. Dual-time-point PET/CT showed markedly elevated (18)F-FDG uptake, which increased from the early to delayed phase. Nevertheless, immunohistochemical analysis of the resected tumor tissue revealed weak expression of glucose transporter-1 and hexokinase II in both tumors. Temporal bone tumors, showing markedly elevated (18)F-FDG uptake, which increases from the early to delayed phase on PET/CT images, may be diagnosed as malignant bone tumors. Therefore, the differential diagnosis should include chondroblastoma in combination with its characteristic findings on CT and MRI.

  1. Dual-time-point FDG-PET/CT Imaging of Temporal Bone Chondroblastoma: A Report of Two Cases

    Directory of Open Access Journals (Sweden)

    Akira Toriihara

    2015-07-01

    Full Text Available Temporal bone chondroblastoma is an extremely rare benign bone tumor. We encountered two cases showing similar imaging findings on computed tomography (CT, magnetic resonance imaging (MRI, and dual-time-point 18F-fluorodeoxyglucose (18F-FDG positron emission tomography (PET/CT. In both cases, CT images revealed temporal bone defects and sclerotic changes around the tumor. Most parts of the tumor showed low signal intensity on T2- weighted MRI images and non-uniform enhancement on gadolinium contrast-enhanced T1-weighted images. No increase in signal intensity was noted in diffusion-weighted images. Dual-time-point PET/CT showed markedly elevated 18F-FDG uptake, which increased from the early to delayed phase. Nevertheless, immunohistochemical analysis of the resected tumor tissue revealed weak expression of glucose transporter-1 and hexokinase II in both tumors. Temporal bone tumors, showing markedly elevated 18F-FDG uptake, which increases from the early to delayed phase on PET/CT images, may be diagnosed as malignant bone tumors. Therefore, the differential diagnosis should include chondroblastoma in combination with its characteristic findings on CT and MRI.

  2. Application of high resolution synchrotron micro-CT radiation in dental implant osseointegration

    DEFF Research Database (Denmark)

    Neldam, Camilla Albeck; Lauridsen, Torsten; Rack, Alexander

    2015-01-01

    The purpose of this study was to describe a refined method using high-resolution synchrotron radiation microtomography (SRmicro-CT) to evaluate osseointegration and peri-implant bone volume fraction after titanium dental implant insertion. SRmicro-CT is considered gold standard evaluating bone...... microarchitecture. Its high resolution, high contrast, and excellent high signal-to-noise-ratio all contribute to the highest spatial resolutions achievable today. Using SRmicro-CT at a voxel size of 5 μm in an experimental goat mandible model, the peri-implant bone volume fraction was found to quickly increase...... to 50% as the radial distance from the implant surface increased, and levelled out to approximately 80% at a distance of 400 μm. This method has been successful in depicting the bone and cavities in three dimensions thereby enabling us to give a more precise answer to the fraction of the bone-to-implant...

  3. Accelerated High-Resolution Photoacoustic Tomography via Compressed Sensing

    CERN Document Server

    Arridge, Simon; Betcke, Marta; Cox, Ben; Huynh, Nam; Lucka, Felix; Ogunlade, Olumide; Zhang, Edward

    2016-01-01

    Current 3D photoacoustic tomography (PAT) systems offer either high image quality or high frame rates but are not able to deliver high spatial and temporal resolution simultaneously, which limits their ability to image dynamic processes in living tissue. A particular example is the planar Fabry-Perot (FP) scanner, which yields high-resolution images but takes several minutes to sequentially map the photoacoustic field on the sensor plane, point-by-point. However, as the spatio-temporal complexity of many absorbing tissue structures is rather low, the data recorded in such a conventional, regularly sampled fashion is often highly redundant. We demonstrate that combining variational image reconstruction methods using spatial sparsity constraints with the development of novel PAT acquisition systems capable of sub-sampling the acoustic wave field can dramatically increase the acquisition speed while maintaining a good spatial resolution: First, we describe and model two general spatial sub-sampling schemes. Then...

  4. Delayed loss of hearing after hearing preservation cochlear implantation: Human temporal bone pathology and implications for etiology.

    Science.gov (United States)

    Quesnel, Alicia M; Nakajima, Hideko Heidi; Rosowski, John J; Hansen, Marlan R; Gantz, Bruce J; Nadol, Joseph B

    2016-03-01

    After initially successful preservation of residual hearing with cochlear implantation, some patients experience subsequent delayed hearing loss. The etiology of such delayed hearing loss is unknown. Human temporal bone pathology is critically important in investigating the etiology, and directing future efforts to maximize long term hearing preservation in cochlear implant patients. Here we present the temporal bone pathology from a patient implanted during life with an Iowa/Nucleus Hybrid S8 implant, with initially preserved residual hearing and subsequent hearing loss. Both temporal bones were removed for histologic processing and evaluated. Complete clinical and audiologic records were available. He had bilateral symmetric high frequency severe to profound hearing loss prior to implantation. Since he was implanted unilaterally, the unimplanted ear was presumed to be representative of the pre-implantation pathology related to his hearing loss. The implanted and contralateral unimplanted temporal bones both showed complete degeneration of inner hair cells and outer hair cells in the basal half of the cochleae, and only mild patchy loss of inner hair cells and outer hair cells in the apical half. The total spiral ganglion neuron counts were similar in both ears: 15,138 (56% of normal for age) in the unimplanted right ear and 13,722 (51% of normal for age) in the implanted left ear. In the basal turn of the implanted left cochlea, loose fibrous tissue and new bone formation filled the scala tympani, and part of the scala vestibuli. Delayed loss of initially preserved hearing after cochlear implantation was not explained by additional post-implantation degeneration of hair cells or spiral ganglion neurons in this patient. Decreased compliance at the round window and increased damping in the scala tympani due to intracochlear fibrosis and new bone formation might explain part of the post-implantation hearing loss. Reduction of the inflammatory and immune response to

  5. [The potential of cone beam computed tomography of the temporal bones in the patients presenting with otosclerosis].

    Science.gov (United States)

    Karpishchenko, S A; Zubareva, A A; Filimonov, V N; Shavgulidze, M A; Azovtseva, E A

    The objective of the present study was to analyze the potential of cone beam computed tomography of the temporal bones in the patients presenting with otosclerosis for the detection of surgically significant specific structural features of the labyrinth wall of the tympanic cavity. More than 400 tomograms of the temporal bones were obtained with the use of a cone beam tomographwere available for the investigation during the period from 2012 till 2016. The study was carried out in several steps, viz. the search for the optimal (for the given instrument) position of the patient, the experimental stage, the retrospective analysis of the tomograms and the comparison of the temporal bones of different types (pneumatic, mixed, and sclerotic) in individual patients, the comparison of the results of cone beam computed tomography (CBCT) with the intraoperative observations, and the modification of the algorithm for the analysis of temporal bone cone beam tomograms. The study included a total of 16 patients (15 women at the age from 32 to 56 years and one managed 58 years) presenting with the clinical diagnosis of otosclerosis. The results of the study were used to elaborate the algorithm for the analysis of cone beam tomograms of the temporal bones to be performed inthe stage by stage manner including the qualitative analysis of tomograms, evaluation of their quantitative parameters and additional characteristics to be taken into consideration when planning the surgical interventions on the labyrinth wall and the tympanic cavity as a preparation for the stapedoplastic treatment. The results of CBCT obtained in the present study were compared with the surgical observations. The diagnostic sensitivity and specificity of the method were estimated to be 100% and 83% respectively. It is concluded that cone beam computed tomography can be employed as a component of the diagnostic algorithm prior to the planning of surgical interventions onthe medial wall of the tympanic cavity

  6. High resolution 3D nonlinear integrated inversion

    Institute of Scientific and Technical Information of China (English)

    Li Yong; Wang Xuben; Li Zhirong; Li Qiong; Li Zhengwen

    2009-01-01

    The high resolution 3D nonlinear integrated inversion method is based on nonlinear theory. Under layer control, the log data from several wells (or all wells) in the study area and seismic trace data adjacent to the wells are input to a network with multiple inputs and outputs and are integratedly trained to obtain an adaptive weight function of the entire study area. Integrated nonlinear mapping relationships are built and updated by the lateral and vertical geologic variations of the reservoirs. Therefore, the inversion process and its inversion results can be constrained and controlled and a stable seismic inversion section with high resolution with velocity inversion, impedance inversion, and density inversion sections, can be gained. Good geologic effects have been obtained in model computation tests and real data processing, which verified that this method has high precision, good practicality, and can be used for quantitative reservoir analysis.

  7. Smartphone microendoscopy for high resolution fluorescence imaging

    CERN Document Server

    Hong, Xiangqian; Mugler, Dale H; Yu, Bing

    2016-01-01

    High resolution optical endoscopes are increasingly used in diagnosis of various medical conditions of internal organs, such as the gastrointestinal tracts, but they are too expensive for use in resource-poor settings. On the other hand, smartphones with high resolution cameras and Internet access have become more affordable, enabling them to diffuse into most rural areas and developing countries in the past decade. In this letter we describe a smartphone microendoscope that can take fluorescence images with a spatial resolution of 3.1 {\\mu}m. Images collected from ex vivo, in vitro and in vivo samples using the device are also presented. The compact and cost-effective smartphone microendoscope may be envisaged as a powerful tool for detecting pre-cancerous lesions of internal organs in low and middle income countries.

  8. Progress toward high resolution EUV spectroscopy

    Science.gov (United States)

    Korendyke, C.; Doschek, G. A.; Warren, H.; Young, P. R.; Chua, D.; Hassler, D. M.; Landi, E.; Davila, J. M.; Klimchuck, J.; Tun, S.; DeForest, C.; Mariska, J. T.; Solar C Spectroscopy Working Group; LEMUR; EUVST Development Team

    2013-07-01

    HIgh resolution EUV spectroscopy is a critical instrumental technique to understand fundamental physical processes in the high temperature solar atmosphere. Spectroscopic observations are used to measure differential emission measure, line of sight and turbulent flows, plasma densities and emission measures. Spatially resolved, spectra of these emission lines with adequate cadence will provide the necessary clues linking small scale structures with large scale, energetic solar phenomena. The necessary observations to determine underlying physical processes and to provide comprehensive temperature coverage of the solar atmosphere above the chromosphere will be obtained by the proposed EUVST instrument for Solar C. This instrument and its design will be discussed in this paper. Progress on the VEry high Resolution Imaging Spectrograph (VERIS) sounding rocket instrument presently under development at the Naval Research Laboratory will also be discussed.

  9. Stellar Tools for High Resolution Population Synthesis

    Science.gov (United States)

    Chávez, M.; Bertone, E.; Rodríguez-Merino, L.; Buzzoni, A.

    2005-12-01

    We present preliminary results of the application of a new stellar library of high-resolution synthetic spectra (based upon ATLAS9 and SYNTHE codes developed by R. L. Kurucz) in the calculation of the ultraviolet-optical spectral energy distribution of simple stellar populations (SSPs). For this purpose, the library has been coupled with Buzzoni's population synthesis code. Part of this paper is also devoted to illustrate quantitatively the extent to which synthetic stellar libraries represent real stars.

  10. Petrous apex mucocele: high resolution CT

    Energy Technology Data Exchange (ETDEWEB)

    Memis, A. [Dept. of Radiology, Hospital of Ege Univ., Bornova, Izmir (Turkey); Memis, A. [Dept. of Radiology, Hospital of Ege Univ., Bornova, Izmir (Turkey); Alper, H. [Dept. of Radiology, Hospital of Ege Univ., Bornova, Izmir (Turkey); Calli, C. [Dept. of Radiology, Hospital of Ege Univ., Bornova, Izmir (Turkey); Ozer, H. [Dept. of Radiology, Hospital of Ege Univ., Bornova, Izmir (Turkey); Ozdamar, N. [Dept. of Neurosurgery, Hospital of Ege Univ., Bornova, Izmir (Turkey)

    1994-11-01

    Mucocele of the petrous apex is very rare, only three cases having been reported. Since this area is inaccessible to direct examination, imaging, preferably high resolution computed tomography (HR CT) is essential. We report a case showing an eroding, non enhancing mass with sharp, lobulated contours, within the petrous apex. The presence of a large air cell on the opposite side suggested a mucocele. (orig.)

  11. High resolution NMR theory and chemical applications

    CERN Document Server

    Becker, Edwin D

    1969-01-01

    High Resolution NMR: Theory and Chemical Applications focuses on the applications of nuclear magnetic resonance (NMR), as well as chemical shifts, lattices, and couplings. The book first offers information on the theory of NMR, including nuclear spin and magnetic moment, spin lattice relaxation, line widths, saturation, quantum mechanical description of NMR, and ringing. The text then ponders on instrumentation and techniques and chemical shifts. Discussions focus on the origin of chemical shifts, reference compounds, empirical correlations of chemical shifts, modulation and phase detection,

  12. 4MOST: the high-resolution spectrograph

    Science.gov (United States)

    Seifert, W.; Xu, W.; Buschkamp, P.; Feiz, C.; Saviauk, A.; Barden, S.; Quirrenbach, A.; Mandel, H.

    2016-08-01

    4MOST (4-meter Multi-Object Spectroscopic Telescope) is a wide-field, fiber-feed, high-multiplex spectroscopic survey facility to be installed on the 4-meter ESO telescope VISTA in Chile. It consists of two identical low resolution spectrographs and one high resolution spectrograph. The instrument is presently in the preliminary design phase and expected to get operational end of 2022. The high resolution spectrograph will afford simultaneous observations of up to 812 targets - over a hexagonal field of view of 4.1 sq.degrees on sky - with a spectral resolution R>18,000 covering a wavelength range from 393 to 679nm in three channels. In this paper we present the optical and mechanical design of the high resolution spectrograph (HRS) as prepared for the review at ESO, Garching. The expected performance including the highly multiplexed fiber slit concept is simulated and its impact on the optical performance given. We show the thermal and finite element analyses and the resulting stability of the spectrograph under operational conditions.

  13. High-resolution traction force microscopy.

    Science.gov (United States)

    Plotnikov, Sergey V; Sabass, Benedikt; Schwarz, Ulrich S; Waterman, Clare M

    2014-01-01

    Cellular forces generated by the actomyosin cytoskeleton and transmitted to the extracellular matrix (ECM) through discrete, integrin-based protein assemblies, that is, focal adhesions, are critical to developmental morphogenesis and tissue homeostasis, as well as disease progression in cancer. However, quantitative mapping of these forces has been difficult since there has been no experimental technique to visualize nanonewton forces at submicrometer spatial resolution. Here, we provide detailed protocols for measuring cellular forces exerted on two-dimensional elastic substrates with a high-resolution traction force microscopy (TFM) method. We describe fabrication of polyacrylamide substrates labeled with multiple colors of fiducial markers, functionalization of the substrates with ECM proteins, setting up the experiment, and imaging procedures. In addition, we provide the theoretical background of traction reconstruction and experimental considerations important to design a high-resolution TFM experiment. We describe the implementation of a new algorithm for processing of images of fiducial markers that are taken below the surface of the substrate, which significantly improves data quality. We demonstrate the application of the algorithm and explain how to choose a regularization parameter for suppression of the measurement error. A brief discussion of different ways to visualize and analyze the results serves to illustrate possible uses of high-resolution TFM in biomedical research. © 2014 Elsevier Inc. All rights reserved.

  14. Temporal variation and lack of host specificity among bacterial endosymbionts of Osedax bone worms (Polychaeta: Siboglinidae

    Directory of Open Access Journals (Sweden)

    Salathé Rahel M

    2012-09-01

    Full Text Available Abstract Background Osedax worms use a proliferative root system to extract nutrients from the bones of sunken vertebrate carcasses. The roots contain bacterial endosymbionts that contribute to the nutrition of these mouthless and gutless worms. The worms acquire these essential endosymbionts locally from the environment in which their larvae settle. Here we report on the temporal dynamics of endosymbiont diversity hosted by nine Osedax species sampled during a three-year investigation of an experimental whale fall at 1820-m depth in the Monterey Bay, California. The host species were identified by their unique mitochondrial COI haplotypes. The endosymbionts were identified by ribotyping with PCR primers specifically designed to target Oceanospirillales. Results Thirty-two endosymbiont ribotypes associated with these worms clustered into two distinct bacterial ribospecies that together comprise a monophyletic group, mostly restricted to deep waters (>1000 m. Statistical analyses confirmed significant changes in the relative abundances of host species and the two dominant endosymbiont ribospecies during the three-year sampling period. Bone type (whale vs. cow also had a significant effect on host species, but not on the two dominant symbiont ribospecies. No statistically significant association existed between the host species and endosymbiont ribospecies. Conclusions Standard PCR and direct sequencing proved to be an efficient method for ribotyping the numerically dominant endosymbiont strains infecting a large sample of host individuals; however, this method did not adequately represent the frequency of mixed infections, which appears to be the rule rather than an exception for Osedax individuals. Through cloning and the use of experimental dilution series, we determined that minority ribotypes constituting less than 30% of a mixture would not likely be detected, leading to underestimates of the frequency of multiple infections in host

  15. Tomografia computadorizada de alta resolução nas complicações pulmonares pós-transplante de medula óssea: ensaio iconográfico High-resolution computed tomography findings in pulmonary complications after bone marrow transplantation: iconographic essay

    Directory of Open Access Journals (Sweden)

    Emerson L. Gasparetto

    2005-12-01

    Full Text Available O transplante de medula óssea (TMO tem sido utilizado como tratamento de escolha para diversas doenças hematológicas. Entretanto, as complicações pulmonares, que podem ocorrer em até 60% dos pacientes, são o principal motivo de falha no tratamento. As complicações pulmonares pós-TMO podem ser divididas em três fases, de acordo com a imunidade do paciente. Na primeira fase, até 30 dias após o procedimento, predominam as complicações não infecciosas e as pneumonias fúngicas. Na fase precoce, que vai até o 100º dia pós-TMO, as infecções virais, principalmente por citomegalovírus, são mais comuns. Finalmente, na fase tardia pós-TMO, complicações não infecciosas como bronquiolite obliterante com pneumonia em organização e doença do enxerto contra o hospedeiro são mais comumente observadas. Os autores apresentam um ensaio iconográfico, enfatizando os aspectos de tomografia de alta resolução em pacientes com complicações pulmonares pós-TMO.Bone marrow transplantation has been the treatment of choice for many hematologic diseases. However, pulmonary complications, which may occur in up to 60% of the patients, are the main cause of treatment failure and may be divided in three phases according to the patient's immunity. In the first phase, up to 30 days after the procedure, there is a predominance of non-infectious complications and fungal pneumonia. Viral infections, mainly by cytomegalovirus, are common in the second phase (up to 100 days after bone marrow transplantation. Finally, in the late phase after bone marrow transplantation, non-infectious complications as bronchiolitis obliterans organizing pneumonia and graft-versus-host disease are most commonly seen. The authors present a pictorial essay of the high-resolution computed tomography findings in patients with pulmonary complications after bone marrow transplantation.

  16. Proceedings of the workshop on high resolution computed microtomography (CMT)

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1997-02-01

    The purpose of the workshop was to determine the status of the field, to define instrumental and computational requirements, and to establish minimum specifications required by possible users. The most important message sent by implementers was the remainder that CMT is a tool. It solves a wide spectrum of scientific problems and is complementary to other microscopy techniques, with certain important advantages that the other methods do not have. High-resolution CMT can be used non-invasively and non-destructively to study a variety of hierarchical three-dimensional microstructures, which in turn control body function. X-ray computed microtomography can also be used at the frontiers of physics, in the study of granular systems, for example. With high-resolution CMT, for example, three-dimensional pore geometries and topologies of soils and rocks can be obtained readily and implemented directly in transport models. In turn, these geometries can be used to calculate fundamental physical properties, such as permeability and electrical conductivity, from first principles. Clearly, use of the high-resolution CMT technique will contribute tremendously to the advancement of current R and D technologies in the production, transport, storage, and utilization of oil and natural gas. It can also be applied to problems related to environmental pollution, particularly to spilling and seepage of hazardous chemicals into the Earth's subsurface. Applications to energy and environmental problems will be far-ranging and may soon extend to disciplines such as materials science--where the method can be used in the manufacture of porous ceramics, filament-resin composites, and microelectronics components--and to biomedicine, where it could be used to design biocompatible materials such as artificial bones, contact lenses, or medication-releasing implants. Selected papers are indexed separately for inclusion in the Energy Science and Technology Database.

  17. Role of high resolution multislice CT scan in otosclerosis

    Directory of Open Access Journals (Sweden)

    Atef EL Maraghy

    2015-11-01

    Full Text Available This prospective study was carried out to assess the radiological findings in patients with otosclerosis using high resolution multislice CT scan and to correlate these findings with audiological findings in those patients. This study was done at Al Azhar University hospitals during the period from Jan 2012 to Jun 2014. Thirty-two patients were enrolled in this study; 13 (40.63% males and 19 (59.37% females. Their age ranged from 13 to 55 with a mean of 36.21 ± 8.7 years. Written consent was taken from all patients. Multislice CT scan was done to all patients and reports were done by computer assisted analysis with thorough audiological assessment including pure tone audiometry, tympanometry and stapedial reflex. Positive findings were present in 40/58 ears (69% while negative findings were present in 18/58 ears (31%. Otosclerotic foci were more detected when slice thickness was lesser than one millimeter especially at fissula ante fenestrum and round window region. There was a good correlation between air bone gap and CT score (p = 0.002. High resolution multislice CT helps in the diagnosis of otosclerosis with sensitivity (69% and it aids in the diagnosis of doubtful cases. Otosclerosis has a special predilection to affect certain sites mainly the fissula ante fenestrum followed by the round window and the cochlear promontory.

  18. Quantitative analysis of cholesteatoma using high resolution computed tomography

    Energy Technology Data Exchange (ETDEWEB)

    Kikuchi, Shigeru; Yamasoba, Tatsuya (Kameda General Hospital, Chiba (Japan)); Iinuma, Toshitaka

    1992-05-01

    Seventy-three cases of adult cholesteatoma, including 52 cases of pars flaccida type cholesteatoma and 21 of pars tensa type cholesteatoma, were examined using high resolution computed tomography, in both axial (lateral semicircular canal plane) and coronal sections (cochlear, vestibular and antral plane). These cases were classified into two subtypes according to the presence of extension of cholesteatoma into the antrum. Sixty cases of chronic otitis media with central perforation (COM) were also examined as controls. Various locations of the middle ear cavity were measured in terms of size in comparison with pars flaccida type cholesteatoma, pars tensa type cholesteatoma and COM. The width of the attic was significantly larger in both pars flaccida type and pars tensa type cholesteatoma than in COM. With pars flaccida type cholesteatoma there was a significantly larger distance between the malleus and lateral wall of the attic than with COM. In contrast, the distance between the malleus and medial wall of the attic was significantly larger with pars tensa type cholesteatoma than with COM. With cholesteatoma extending into the antrum, regardless of the type of cholesteatoma, there were significantly larger distances than with COM at the following sites: the width and height of the aditus ad antrum, and the width, height and anterior-posterior diameter of the antrum. However, these distances were not significantly different between cholesteatoma without extension into the antrum and COM. The hitherto demonstrated qualitative impressions of bone destruction in cholesteatoma were quantitatively verified in detail using high resolution computed tomography. (author).

  19. Temporal bone studies of the human peripheral vestibular system. Aminoglycoside ototoxicity.

    Science.gov (United States)

    Tsuji, K; Velázquez-Villaseñor, L; Rauch, S D; Glynn, R J; Wall, C; Merchant, S N

    2000-05-01

    Quantitative assessments of vestibular hair cells and Scarpa's ganglion cells were performed on 17 temporal bones from 10 individuals who had well-documented clinical evidence of aminoglycoside ototoxicity (streptomycin, kanamycin, and neomycin). Assessment of vestibular hair cells was performed by Nomarski (differential interference contrast) microscopy. Hair cell counts were expressed as densities (number of cells per 0.01 mm2 surface area of the sensory epithelium). The results were compared with age-matched normal data. Streptomycin caused a significant loss of both type I and type II hair cells in all 5 vestibular sense organs. In comparing the ototoxic effect on type I versus type II hair cells, there was greater type I hair cell loss for all 3 cristae, but not for the maculae. The vestibular ototoxic effects of kanamycin appeared to be similar to those of streptomycin, but the small sample size precluded definitive conclusions from being made. Neomycin did not cause loss of vestibular hair cells. Within the limits of this study (maximum postototoxicity survival time of 12 months), there was no significant loss of Scarpa's ganglion cells for any of the 3 drugs. The findings have implications in several clinical areas, including the correlation of vestibular test results to pathological findings, the rehabilitation of patients with vestibular ototoxicity, the use of aminoglycosides to treat Meniere's disease, and the development of a vestibular prosthesis.

  20. The new mid-scala electrode array: a radiologic and histologic study in human temporal bones.

    Science.gov (United States)

    Hassepass, Frederike; Bulla, Stefan; Maier, Wolfgang; Laszig, Roland; Arndt, Susan; Beck, Rainer; Traser, Lousia; Aschendorff, Antje

    2014-09-01

    To analyze the quality of insertion of the newly developed midscala (MS) electrode, which targets a midscalar electrode position to reduce the risk of trauma to the lateral wall and the modiolus. Modern cochlear implant surgery aims for a safe intracochlear placement of electrode arrays with an ongoing debate regarding cochleostomy or round window (RW) insertion and the use of lateral wall or perimodiolar electrode placement. Intracochlear trauma after insertion of different electrodes depends on insertion mode and electrode design and may result in trauma to the delicate structures of the cochlear. We performed a temporal bone (TB) trial with insertion of the MS electrode in n = 20 TB's after a mastoidectomy and posterior tympanotomy. Insertion was performed either via the RW or a cochleostomy. Electrode positioning, length of insertion, and angle of insertion were analyzed with rotational tomography (RT). TBs were histologically analyzed. Results of RT and histology were compared. Scala tympani (ST) insertion could be accomplished reliably by both RW and via a cochleostomy approach. In 20 TBs, 1 scala vestibuli insertion, 1 incomplete (ST), and 1 elevation of basilar membrane were depicted. No trauma was found in 94.7% of all ST insertions. RT allowed determination of the intracochlear electrode position, which was specified by histologic sectioning. The new MS electrode seems to fulfill reliable atraumatic intracochlear placement via RW and cochleostomy approaches. RT is available for evaluation of intracochlear electrode position, serving as a potential quality control instrument in human implantation.

  1. A 3-D analysis of the protympanum in human temporal bones with chronic ear disease.

    Science.gov (United States)

    Pauna, Henrique F; Monsanto, Rafael C; Schachern, Patricia; Paparella, Michael M; Cureoglu, Sebahattin

    2017-03-01

    Eustachian tube dysfunction is believed to be an important factor to cholesteatoma development and recurrence of disease after surgical treatment. Although many studies have described prognostic factors, evaluation methods, or surgical techniques for Eustachian tube dysfunction, they relied on the soft tissues of its structure; little is known about its bony structure-the protympanum-which connects the Eustachian tube to the tympanic cavity, and can also be affected by several inflammatory conditions, both from the middle ear or from the nasopharynx. We studied temporal bones from patients with cholesteatoma, chronic otitis media (with and without retraction pockets), purulent otitis media, and non-diseased ears, looking for differences between the volume of the protympanum, the diameter of the Eustachian tube isthmus, and the distance between the anterior tympanic annulus and the promontory. Light microscopy and 3-D reconstruction software were used for the measurements. We observed a decrease of volume in the lumen of the four middle ear diseased ears compared to the control group. We observed a significant decrease in the volume of the protympanic space in the cholesteatoma group compared to the chronic otitis media group. We also observed a decrease in the bony space (protympanum space) in cholesteatoma, chronic otitis media with retraction pockets, and purulent otitis media compared to the control group. We found a correlation in middle ear diseases and a decrease in the middle ear space. Our findings may suggest that a smaller bony volume in the protympanic area may trigger middle ear dysventilation problems.

  2. Differential Intracochlear Sound Pressure Measurements in Human Temporal Bones with an Off-the-Shelf Sensor.

    Science.gov (United States)

    Grossöhmichen, Martin; Salcher, Rolf; Püschel, Klaus; Lenarz, Thomas; Maier, Hannes

    2016-01-01

    The standard method to determine the output level of acoustic and mechanical stimulation to the inner ear is measurement of vibration response of the stapes in human cadaveric temporal bones (TBs) by laser Doppler vibrometry. However, this method is reliable only if the intact ossicular chain is stimulated. For other stimulation modes an alternative method is needed. The differential intracochlear sound pressure between scala vestibuli (SV) and scala tympani (ST) is assumed to correlate with excitation. Using a custom-made pressure sensor it has been successfully measured and used to determine the output level of acoustic and mechanical stimulation. To make this method generally accessible, an off-the-shelf pressure sensor (Samba Preclin 420 LP, Samba Sensors) was tested here for intracochlear sound pressure measurements. During acoustic stimulation, intracochlear sound pressures were simultaneously measurable in SV and ST between 0.1 and 8 kHz with sufficient signal-to-noise ratios with this sensor. The pressure differences were comparable to results obtained with custom-made sensors. Our results demonstrated that the pressure sensor Samba Preclin 420 LP is usable for measurements of intracochlear sound pressures in SV and ST and for the determination of differential intracochlear sound pressures.

  3. A High Resolution Scale-of-four

    Science.gov (United States)

    Fitch, V.

    1949-08-25

    A high resolution scale-of-four has been developed to be used in conjunction with the nuclear particle detection devices in applications where the counting rate is unusually high. Specifically, it is intended to precede the commercially available medium resolution scaling circuits and so decrease the resolving time of the counting system. The circuit will function reliably on continuously recurring pulses separated by less than 0.1 microseconds. It will resolve two pulses (occurring at a moderate repetition rate) which are spaced at 0.04 microseconds. A five-volt input signal is sufficient to actuate the device.

  4. SPIRAL2/DESIR high resolution mass separator

    Energy Technology Data Exchange (ETDEWEB)

    Kurtukian-Nieto, T., E-mail: kurtukia@cenbg.in2p3.fr [Centre d’Études Nucléaires de Bordeaux Gradignan, Université Bordeaux 1-CNRS/IN2P3, BP 120, F-33175 Gradignan Cedex (France); Baartman, R. [TRIUMF, 4004 Wesbrook Mall, Vancouver B.C., V6T 2A3 (Canada); Blank, B.; Chiron, T. [Centre d’Études Nucléaires de Bordeaux Gradignan, Université Bordeaux 1-CNRS/IN2P3, BP 120, F-33175 Gradignan Cedex (France); Davids, C. [Physics Division, Argonne National Laboratory, Argonne, IL 60439 (United States); Delalee, F. [Centre d’Études Nucléaires de Bordeaux Gradignan, Université Bordeaux 1-CNRS/IN2P3, BP 120, F-33175 Gradignan Cedex (France); Duval, M. [GANIL, CEA/DSM-CNRS/IN2P3, Bd Henri Becquerel, BP 55027, F-14076 Caen Cedex 5 (France); El Abbeir, S.; Fournier, A. [Centre d’Études Nucléaires de Bordeaux Gradignan, Université Bordeaux 1-CNRS/IN2P3, BP 120, F-33175 Gradignan Cedex (France); Lunney, D. [CSNSM-IN2P3-CNRS, Université de Paris Sud, F-91405 Orsay (France); Méot, F. [BNL, Upton, Long Island, New York (United States); Serani, L. [Centre d’Études Nucléaires de Bordeaux Gradignan, Université Bordeaux 1-CNRS/IN2P3, BP 120, F-33175 Gradignan Cedex (France); Stodel, M.-H.; Varenne, F. [GANIL, CEA/DSM-CNRS/IN2P3, Bd Henri Becquerel, BP 55027, F-14076 Caen Cedex 5 (France); and others

    2013-12-15

    DESIR is the low-energy part of the SPIRAL2 ISOL facility under construction at GANIL. DESIR includes a high-resolution mass separator (HRS) with a designed resolving power m/Δm of 31,000 for a 1 π-mm-mrad beam emittance, obtained using a high-intensity beam cooling device. The proposed design consists of two 90-degree magnetic dipoles, complemented by electrostatic quadrupoles, sextupoles, and a multipole, arranged in a symmetric configuration to minimize aberrations. A detailed description of the design and results of extensive simulations are given.

  5. Fast Backprojection Techniques for High Resolution Tomography

    CERN Document Server

    Koshev, Nikolay; Miqueles, Eduardo X

    2016-01-01

    Fast image reconstruction techniques are becoming important with the increasing number of scientific cases in high resolution micro and nano tomography. The processing of the large scale three-dimensional data demands new mathematical tools for the tomographic reconstruction task because of the big computational complexity of most current algorithms as the sizes of tomographic data grow with the development of more powerful acquisition hardware and more refined scientific needs. In the present paper we propose a new fast back-projection operator for the processing of tomographic data and compare it against other fast reconstruction techniques.

  6. Single shot high resolution digital holography.

    Science.gov (United States)

    Khare, Kedar; Ali, P T Samsheer; Joseph, Joby

    2013-02-11

    We demonstrate a novel computational method for high resolution image recovery from a single digital hologram frame. The complex object field is obtained from the recorded hologram by solving a constrained optimization problem. This approach which is unlike the physical hologram replay process is shown to provide high quality image recovery even when the dc and the cross terms in the hologram overlap in the Fourier domain. Experimental results are shown for a Fresnel zone hologram of a resolution chart, intentionally recorded with a small off-axis reference beam angle. Excellent image recovery is observed without the presence of dc or twin image terms and with minimal speckle noise.

  7. High resolution SAR applications and instrument design

    Science.gov (United States)

    Dionisio, C.; Torre, A.

    1993-01-01

    The Synthetic Aperture Radar (SAR) has viewed, in the last two years, a huge increment of interest from many preset and potential users. The good spatial resolution associated to the all weather capability lead to considering SAR not only a scientific instrument but a tool for verifying and controlling the daily human relationships with the Earth Environment. New missions were identified for SAR as spatial resolution became lower than three meters: disasters, pollution, ships traffic, volcanic eruptions, earthquake effect are only a few of the possible objects which can be effectively detected, controlled and monitored by SAR mounted on satellites. High resolution radar design constraints and dimensioning are discussed.

  8. Principles of high resolution NMR in solids

    CERN Document Server

    Mehring, Michael

    1983-01-01

    The field of Nuclear Magnetic Resonance (NMR) has developed at a fascinating pace during the last decade. It always has been an extremely valuable tool to the organic chemist by supplying molecular "finger print" spectra at the atomic level. Unfortunately the high resolution achievable in liquid solutions could not be obtained in solids and physicists and physical chemists had to live with unresolved lines open to a wealth of curve fitting procedures and a vast amount of speculations. High resolution NMR in solids seemed to be a paradoxon. Broad structure­ less lines are usually encountered when dealing with NMR in solids. Only with the recent advent of mUltiple pulse, magic angle, cross-polarization, two-dimen­ sional and multiple-quantum spectroscopy and other techniques during the last decade it became possible to resolve finer details of nuclear spin interactions in solids. I have felt that graduate students, researchers and others beginning to get involved with these techniques needed a book which trea...

  9. Limiting liability via high resolution image processing

    Energy Technology Data Exchange (ETDEWEB)

    Greenwade, L.E.; Overlin, T.K.

    1996-12-31

    The utilization of high resolution image processing allows forensic analysts and visualization scientists to assist detectives by enhancing field photographs, and by providing the tools and training to increase the quality and usability of field photos. Through the use of digitized photographs and computerized enhancement software, field evidence can be obtained and processed as `evidence ready`, even in poor lighting and shadowed conditions or darkened rooms. These images, which are most often unusable when taken with standard camera equipment, can be shot in the worst of photographic condition and be processed as usable evidence. Visualization scientists have taken the use of digital photographic image processing and moved the process of crime scene photos into the technology age. The use of high resolution technology will assist law enforcement in making better use of crime scene photography and positive identification of prints. Valuable court room and investigation time can be saved and better served by this accurate, performance based process. Inconclusive evidence does not lead to convictions. Enhancement of the photographic capability helps solve one major problem with crime scene photos, that if taken with standard equipment and without the benefit of enhancement software would be inconclusive, thus allowing guilty parties to be set free due to lack of evidence.

  10. High-Resolution Scintimammography: A Pilot Study

    Energy Technology Data Exchange (ETDEWEB)

    Rachel F. Brem; Joelle M. Schoonjans; Douglas A. Kieper; Stan Majewski; Steven Goodman; Cahid Civelek

    2002-07-01

    This study evaluated a novel high-resolution breast-specific gamma camera (HRBGC) for the detection of suggestive breast lesions. Methods: Fifty patients (with 58 breast lesions) for whom a scintimammogram was clinically indicated were prospectively evaluated with a general-purpose gamma camera and a novel HRBGC prototype. The results of conventional and high-resolution nuclear studies were prospectively classified as negative (normal or benign) or positive (suggestive or malignant) by 2 radiologists who were unaware of the mammographic and histologic results. All of the included lesions were confirmed by pathology. Results: There were 30 benign and 28 malignant lesions. The sensitivity for detection of breast cancer was 64.3% (18/28) with the conventional camera and 78.6% (22/28) with the HRBGC. The specificity with both systems was 93.3% (28/30). For the 18 nonpalpable lesions, sensitivity was 55.5% (10/18) and 72.2% (13/18) with the general-purpose camera and the HRBGC, respectively. For lesions 1 cm, 7 of 15 were detected with the general-purpose camera and 10 of 15 with the HRBGC. Four lesions (median size, 8.5 mm) were detected only with the HRBGC and were missed by the conventional camera. Conclusion: Evaluation of indeterminate breast lesions with an HRBGC results in improved sensitivity for the detection of cancer, with greater improvement shown for nonpalpable and 1-cm lesions.

  11. High-Resolution PET Detector. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Karp, Joel

    2014-03-26

    The objective of this project was to develop an understanding of the limits of performance for a high resolution PET detector using an approach based on continuous scintillation crystals rather than pixelated crystals. The overall goal was to design a high-resolution detector, which requires both high spatial resolution and high sensitivity for 511 keV gammas. Continuous scintillation detectors (Anger cameras) have been used extensively for both single-photon and PET scanners, however, these instruments were based on NaI(Tl) scintillators using relatively large, individual photo-multipliers. In this project we investigated the potential of this type of detector technology to achieve higher spatial resolution through the use of improved scintillator materials and photo-sensors, and modification of the detector surface to optimize the light response function.We achieved an average spatial resolution of 3-mm for a 25-mm thick, LYSO continuous detector using a maximum likelihood position algorithm and shallow slots cut into the entrance surface.

  12. Digital interface for high-resolution displays

    Science.gov (United States)

    Hermann, David J.; Gorenflo, Ronald L.

    1999-08-01

    Commercial display interfaces are currently transitioning from analog to digital. Although this transition is in the very early stages, the military needs to begin planning their own transition to digital. There are many problems with the analog interface in high-resolution display systems that are solved by changing to a digital interface. Also, display system cost can be lower with a digital interface to a high resolution display. Battelle is under contract with DARPA to develop an advanced Display Interface (ADI) to replace the analog RGB interfaces currently used in high definition workstation displays. The goal is to create a standard digital display interface for military applications that is based on emerging commercial standards. Support for military application- specific functionality is addressed, including display test and control. The main challenges to implementing a digital display interface are described, along with approaches to address the problems. Conceptual ADI architectures are described and contrasted. The current and emerging commercial standards for digital display interfaces are reviewed in detail. Finally, the tasks required to complete the ADI effort are outlined and described.

  13. Inclusion body myopathy, Paget's disease of the bone and fronto-temporal dementia: a disorder of autophagy

    OpenAIRE

    Ju, Jeong-Sun; Weihl, Conrad C

    2010-01-01

    Inclusion body myopathy associated with Paget's disease of the bone and fronto-temporal dementia (IBMPFD) is a progressive autosomal dominant disorder caused by mutations in p97/VCP (valosin-containing protein). p97/VCP is a member of the AAA+ (ATPase associated with a variety of activities) protein family and participates in multiple cellular processes. One particularly important role for p97/VCP is facilitating intracellular protein degradation. p97/VCP has traditionally been thought to med...

  14. Pou3f4-mediated regulation of ephrin-b2 controls temporal bone development in the mouse.

    Directory of Open Access Journals (Sweden)

    Steven Raft

    Full Text Available The temporal bone encases conductive and sensorineural elements of the ear. Mutations of POU3F4 are associated with unique temporal bone abnormalities and X-linked mixed deafness (DFNX2/DFN3. However, the target genes and developmental processes controlled by POU3F4 transcription factor activity have remained largely uncharacterized. Ephrin-B2 (Efnb2 is a signaling molecule with well-documented effects on cell adhesion, proliferation, and migration. Our analyses of targeted mouse mutants revealed that Efnb2 loss-of-function phenocopies temporal bone abnormalities of Pou3f4 hemizygous null neonates: qualitatively identical malformations of the stapes, styloid process, internal auditory canal, and cochlear capsule were present in both mutants. Using failed/insufficient separation of the stapes and styloid process as a quantitative trait, we found that single gene Efnb2 loss-of-function and compound Pou3f4/Efnb2 loss-of-function caused a more severe phenotype than single gene Pou3f4 loss-of-function. Pou3f4 and Efnb2 gene expression domains overlapped at the site of impending stapes-styloid process separation and at subcapsular mesenchyme surrounding the cochlea; at both these sites, Efnb2 expression was attenuated in Pou3f4 hemizygous null mutants relative to control. Results of immunoprecipitation experiments using chromatin isolated from nascent middle ear mesenchyme supported the hypothesis of a physical association between Pou3f4 and specific non-coding sequence of Efnb2. We propose that Efnb2 is a target of Pou3f4 transcription factor activity and an effector of mesenchymal patterning during temporal bone development.

  15. End User Comparison of Anatomically Matched 3-Dimensional Printed and Virtual Haptic Temporal Bone Simulation: A Pilot Study.

    Science.gov (United States)

    Hochman, Jordan Brent; Rhodes, Charlotte; Kraut, Jay; Pisa, Justyn; Unger, Bertram

    2015-08-01

    Simulation has assumed a prominent role in education. It is important to explore the effectiveness of different modalities. In this article, we directly compare surgical resident impression of 2 distinct temporal bone simulations (physical and haptic). Research Ethics Board-approved prospective cohort study. A haptic voxel-based virtual model (VM) and a physical 3-dimensional printed temporal bone model (PBM) were developed. Participants rated each construct on a number of parameters and performed a direct comparison of the simulations using a survey instrument that employed a 7-point Likert scale and rank lists. Ten otolaryngology residents dissected anatomically identical, matched physical and virtual models. Data for both simulations originated from 10 unique cadaveric micro-computed tomography images. Subjects rated the PBM drill quality as being more similar to cadaveric temporal bone than the VM (cortical bone mean: 5.5 vs 3.2, P = .011; trabecular bone mean: 5.2 vs 2.8, P = .004) and with better air cell system representation (mean: 5.4 vs 4.5, P = .003). Subjects strongly agreed that both simulations are effective educational tools, but they rated the PBM higher (mean: 6.7 vs 5.4, P = .019). Notably, subjects agreed that both modalities should be integrated into training, but they were more favorably inclined toward the PBM (mean: 7.0 vs 5.5, P = .002). In direct comparison, the PBM was the preferred simulation in 7 of 9 educational domains. Appraisal of a PBM and a VM found both to have perceived educational benefit. However, the PBM was considered to have more realistic physical properties and was considered the preferred training instrument. © American Academy of Otolaryngology—Head and Neck Surgery Foundation 2015.

  16. A high-resolution record of Greenland mass balance

    Science.gov (United States)

    McMillan, Malcolm; Leeson, Amber; Shepherd, Andrew; Briggs, Kate; Armitage, Thomas W. K.; Hogg, Anna; Kuipers Munneke, Peter; Broeke, Michiel; Noël, Brice; Berg, Willem Jan; Ligtenberg, Stefan; Horwath, Martin; Groh, Andreas; Muir, Alan; Gilbert, Lin

    2016-07-01

    We map recent Greenland Ice Sheet elevation change at high spatial (5 km) and temporal (monthly) resolution using CryoSat-2 altimetry. After correcting for the impact of changing snowpack properties associated with unprecedented surface melting in 2012, we find good agreement (3 cm/yr bias) with airborne measurements. With the aid of regional climate and firn modeling, we compute high spatial and temporal resolution records of Greenland mass evolution, which correlate (R = 0.96) with monthly satellite gravimetry and reveal glacier dynamic imbalance. During 2011-2014, Greenland mass loss averaged 269 ± 51 Gt/yr. Atmospherically driven losses were widespread, with surface melt variability driving large fluctuations in the annual mass deficit. Terminus regions of five dynamically thinning glaciers, which constitute less than 1% of Greenland's area, contributed more than 12% of the net ice loss. This high-resolution record demonstrates that mass deficits extending over small spatial and temporal scales have made a relatively large contribution to recent ice sheet imbalance.

  17. High resolution solar observations from first principles to applications

    Science.gov (United States)

    Verdoni, Angelo P.

    2009-10-01

    The expression "high-resolution observations" in Solar Physics refers to the spatial, temporal and spectral domains in their entirety. High-resolution observations of solar fine structure are a necessity to answer many of the intriguing questions related to solar activity. However, a researcher building instruments for high-resolution observations has to cope with the fact that these three domains often have diametrically opposed boundary conditions. Many factors have to be considered in the design of a successful instrument. Modern post-focus instruments are more closely linked with the solar telescopes that they serve than in past. In principle, the quest for high-resolution observations already starts with the selection of the observatory site. The site survey of the Advanced Technology Solar Telescope (ATST) under the stewardship of the National Solar Observatory (NSO) has identified Big Bear Solar Observatory (BBSO) as one of the best sites for solar observations. In a first step, the seeing characteristics at BBSO based on the data collected for the ATST site survey are described. The analysis will aid in the scheduling of high-resolution observations at BBSO as well as provide useful information concerning the design and implementation of a thermal control system for the New Solar Telescope (NST). NST is an off-axis open-structure Gregorian-style telescope with a 1.6 m aperture. NST will be housed in a newly constructed 5/8-sphere ventilated dome. With optics exposed to the surrounding air, NST's open-structure design makes it particularly vulnerable to the effects of enclosure-related seeing. In an effort to mitigate these effects, the initial design of a thermal control system for the NST dome is presented. The goal is to remediate thermal related seeing effects present within the dome interior. The THermal Control System (THCS) is an essential component for the open-telescope design of NST to work. Following these tasks, a calibration routine for the

  18. Improved methods for high resolution electron microscopy

    Energy Technology Data Exchange (ETDEWEB)

    Taylor, J.R.

    1987-04-01

    Existing methods of making support films for high resolution transmission electron microscopy are investigated and novel methods are developed. Existing methods of fabricating fenestrated, metal reinforced specimen supports (microgrids) are evaluated for their potential to reduce beam induced movement of monolamellar crystals of C/sub 44/H/sub 90/ paraffin supported on thin carbon films. Improved methods of producing hydrophobic carbon films by vacuum evaporation, and improved methods of depositing well ordered monolamellar paraffin crystals on carbon films are developed. A novel technique for vacuum evaporation of metals is described which is used to reinforce microgrids. A technique is also developed to bond thin carbon films to microgrids with a polymer bonding agent. Unique biochemical methods are described to accomplish site specific covalent modification of membrane proteins. Protocols are given which covalently convert the carboxy terminus of papain cleaved bacteriorhodopsin to a free thiol. 53 refs., 19 figs., 1 tab.

  19. Constructing a WISE High Resolution Galaxy Atlas

    Science.gov (United States)

    Jarrett, T. H.; Masci, F.; Tsai, C. W.; Petty, S.; Cluver, M.; Assef, Roberto J.; Benford, D.; Blain, A.; Bridge, C.; Donoso, E.; Eisenhardt, P.; Fowler, J.; Koribalski, B.; Lake, S.; Neill, James D.; Seibert, M.; Stanford, S.; Wright, E.

    2012-01-01

    After eight months of continuous observations, the Wide-field Infrared Survey Explorer (WISE) mapped the entire sky at 3.4 micron, 4.6 micron, 12 micron, and 22 micron. We have begun a dedicated WISE High Resolution Galaxy Atlas project to fully characterize large, nearby galaxies and produce a legacy image atlas and source catalog. Here we summarize the deconvolution techniques used to significantly improve the spatial resolution of WISE imaging, specifically designed to study the internal anatomy of nearby galaxies. As a case study, we present results for the galaxy NGC 1566, comparing the WISE enhanced-resolution image processing to that of Spitzer, Galaxy Evolution Explorer, and ground-based imaging. This is the first paper in a two-part series; results for a larger sample of nearby galaxies are presented in the second paper.

  20. Speleothems as high-resolution paleoflood archives

    Science.gov (United States)

    Denniston, Rhawn F.; Luetscher, Marc

    2017-08-01

    Over the last two decades, speleothems have become widely utilized records of past environmental variability, typically through their stable isotopic and trace elemental chemistry. Numerous speleothem researchers have identified evidence of flooding recorded by detrital layers trapped within speleothems, but few studies have developed paleoflood reconstructions from such samples. Because they can be precisely dated, are generally immune to post-depositional distortion or erosion, and can be tied to a fixed elevational baseline, speleothems hold enormous potential as high-resolution archives of cave floods, and thus as proxies for extreme rainfall or other hydrologic drivers of cave flooding. Here we review speleothem-based paleoflood reconstruction methods, identify potential biases and pitfalls, and suggest standard practices for future studies.

  1. High-resolution CT of otosclerosis

    Energy Technology Data Exchange (ETDEWEB)

    Dewen, Yang; Kodama, Takao; Tono, Tetsuya; Ochiai, Reiji; Kiyomizu, Kensuke; Suzuki, Yukiko; Yano, Takanori; Watanabe, Katsushi [Miyazaki Medical Coll., Kiyotake (Japan)

    1997-11-01

    High-resolution CT (HRCT) scans of thirty-two patients (60 ears) with the clinical diagnosis of fenestral otosclerosis were evaluated retrospectively. HRCT was performed with 1-mm-thick targeted sections and 1-mm (36 ears) or 0.5-mm (10 ears) intervals in the semiaxial projection. Seven patients (14 ears) underwent helical scanning with a 1-mm slice thickness and 1-mm/sec table speed. Forty-five ears (75%) were found to have one or more otospongiotic or otosclerotic foci on HRCT. In most instances (30 ears), the otospongiotic foci were found in the region of the fissula ante fenestram. No significant correlations between CT findings and air conduction threshold were observed. We found a significant relationship between lesions of the labyrinthine capsule and sensorineural hearing loss. We conclude that HRCT is a valuable modality for diagnosing otosclerosis, especially when otospongiotic focus is detected. (author)

  2. High-resolution TOF with RPCs

    Energy Technology Data Exchange (ETDEWEB)

    Fonte, P. E-mail: fonte@lipc.fis.uc.pt; Peskov, V

    2002-01-21

    In this work, we describe some recent results concerning the application of Resistive Plate Chambers operated in avalanche mode at atmospheric pressure for high-resolution time-of-flight measurements. A combination of multiple, mechanically accurate, thin gas gaps and state-of-the-art electronics yielded an overall (detector plus electronics) timing accuracy better than 50 ps {sigma} with a detection efficiency up to 99% for MIPs. Single gap chambers were also tested in order to clarify experimentally several aspects of the mode of operation of these detectors. These results open perspectives of affordable and reliable high granularity large area TOF detectors, with an efficiency and time resolution comparable to the existing scintillator-based TOF technology but with a significantly, up to an order of magnitude, lower price per channel.

  3. High resolution studies of massive primordial haloes

    CERN Document Server

    Latif, M A; Schmidt, W; Niemeyer, J

    2012-01-01

    Atomic cooling haloes with T_vir > 10^4 K are the most plausible sites for the formation of the first galaxies. In this article, we aim to study the implications of gravity driven turbulence in protogalactic haloes. By varying the resolution per Jeans length, we explore whether the turbulent cascade is resolved well enough to obtain converged results. We have performed high resolution cosmological simulations using the adaptive mesh refinement code Enzo including a subgrid-scale turbulence model to study the role of unresolved turbulence. We compared the results of three different Jeans resolutions from 16 to 64 cells. While radially averaged profiles roughly agree at different resolutions, differences in the morphology reveal that even the highest resolution employed provides no convergence. Moreover, taking into account unresolved turbulence significantly influences the morphology of a halo. We have quantified the properties of the high-density clumps in the halo. These clumps are gravitationally unbound wi...

  4. GRANULOMETRIC MAPS FROM HIGH RESOLUTION SATELLITE IMAGES

    Directory of Open Access Journals (Sweden)

    Catherine Mering

    2011-05-01

    Full Text Available A new method of land cover mapping from satellite images using granulometric analysis is presented here. Discontinuous landscapes such as steppian bushes of semi arid regions and recently growing urban settlements are especially concerned by this study. Spatial organisations of the land cover are quantified by means of the size distribution analysis of the land cover units extracted from high resolution remotely sensed images. A granulometric map is built by automatic classification of every pixel of the image according to the granulometric density inside a sliding neighbourhood. Granulometric mapping brings some advantages over traditional thematic mapping by remote sensing by focusing on fine spatial events and small changes in one peculiar category of the landscape.

  5. High resolution CT of Meckel's cave.

    Science.gov (United States)

    Chui, M; Tucker, W; Hudson, A; Bayer, N

    1985-01-01

    High resolution CT of the parasellar region was carried out in 50 patients studied for suspected pituitary microadenoma, but who showed normal pituitary gland or microadenoma on CT. This control group of patients all showed an ellipsoid low-density area in the posterior parasellar region. Knowledge of the gross anatomy and correlation with metrizamide cisternography suggest that the low density region represents Meckel's cave, rather than just the trigeminal ganglion alone. Though there is considerable variation in the size of Meckel's cave in different patients as well as the two sides of the same patient, the rather constant ellipsoid configuration of the cave in normal subjects will aid in diagnosing small pathological lesions, thereby obviating more invasive cisternography via the transovale or lumbar route. Patients with "idiopathic" tic douloureux do not show a Meckel's cave significantly different from the control group.

  6. Venus gravity - A high-resolution map

    Science.gov (United States)

    Reasenberg, R. D.; Goldberg, Z. M.; Macneil, P. E.; Shapiro, I. I.

    1981-01-01

    The Doppler data from the radio tracking of the Pioneer Venus Orbiter (PVO) have been used in a two-stage analysis to develop a high-resolution map of the gravitational potential of Venus, represented by a central mass and a surface mass density. The two-stage procedure invokes a Kalman filter-smoother to determine the orbit of the spacecraft, and a stabilized linear inverter to estimate the surface mass density. The resultant gravity map is highly correlated with the topographic map derived from the PVO radar altimeter data. However, the magnitudes of the gravity variations are smaller than would be expected if the topography were uncompensated, indicating that at least partial compensation has taken place.

  7. High-resolution electrohydrodynamic jet printing

    Science.gov (United States)

    Park, Jang-Ung; Hardy, Matt; Kang, Seong Jun; Barton, Kira; Adair, Kurt; Mukhopadhyay, Deep Kishore; Lee, Chang Young; Strano, Michael S.; Alleyne, Andrew G.; Georgiadis, John G.; Ferreira, Placid M.; Rogers, John A.

    2007-10-01

    Efforts to adapt and extend graphic arts printing techniques for demanding device applications in electronics, biotechnology and microelectromechanical systems have grown rapidly in recent years. Here, we describe the use of electrohydrodynamically induced fluid flows through fine microcapillary nozzles for jet printing of patterns and functional devices with submicrometre resolution. Key aspects of the physics of this approach, which has some features in common with related but comparatively low-resolution techniques for graphic arts, are revealed through direct high-speed imaging of the droplet formation processes. Printing of complex patterns of inks, ranging from insulating and conducting polymers, to solution suspensions of silicon nanoparticles and rods, to single-walled carbon nanotubes, using integrated computer-controlled printer systems illustrates some of the capabilities. High-resolution printed metal interconnects, electrodes and probing pads for representative circuit patterns and functional transistors with critical dimensions as small as 1μm demonstrate potential applications in printed electronics.

  8. Georadar - high resolution geophysical electromagnetic device

    Directory of Open Access Journals (Sweden)

    Janez Stern

    1995-12-01

    Full Text Available Georadar is a high resolution geophysical electromagnetic device that was developed in the first part of the 1980's. In Slovenia it was first tested in 1991 on several objects of economicgeological, geotechnical and hydrogeologic nature.Here its usefulness in karst studied is presented. The first part of the paper deals with description of measurement procedure and methodological bases, and the second part with experience and results of case histories. Shown are radargrams from ornamental stone quarry Hotavlje, calcite mine Stahovica, Golobja jama karstcave near Divača and from highway construction site Razdrto-Čebulovica. All measurements were performed with the georadar instrument Pulse EKKO IV with a lOOMHz antenna according to the method of reflection profiling.

  9. Novel high-resolution VGA QWIP detector

    Science.gov (United States)

    Kataria, H.; Asplund, C.; Lindberg, A.; Smuk, S.; Alverbro, J.; Evans, D.; Sehlin, S.; Becanovic, S.; Tinghag, P.; Höglund, L.; Sjöström, F.; Costard, E.

    2017-02-01

    Continuing with its legacy of producing high performance infrared detectors, IRnova introduces its high resolution LWIR IDDCA (Integrated Detector Dewar Cooler assembly) based on QWIP (quantum well infrared photodetector) technology. The Focal Plane Array (FPA) has 640×512 pixels, with small (15μm) pixel pitch, and is based on the FLIRIndigo ISC0403 Readout Integrated Circuit (ROIC). The QWIP epitaxial structures are grown by metal-organic vapor phase epitaxy (MOVPE) at IRnova. Detector stability and response uniformity inherent to III/V based material will be demonstrated in terms of high performing detectors. Results showing low NETD at high frame rate will be presented. This makes it one of the first 15μm pitch QWIP based LWIR IDDCA commercially available on the market. High operability and stability of our other QWIP based products will also be shared.

  10. High-Resolution Movement EEG Classification

    Directory of Open Access Journals (Sweden)

    Jakub Štastný

    2007-01-01

    Full Text Available The aim of the contribution is to analyze possibilities of high-resolution movement classification using human EEG. For this purpose, a database of the EEG recorded during right-thumb and little-finger fast flexion movements of the experimental subjects was created. The statistical analysis of the EEG was done on the subject's basis instead of the commonly used grand averaging. Statistically significant differences between the EEG accompanying movements of both fingers were found, extending the results of other so far published works. The classifier based on hidden Markov models was able to distinguish between movement and resting states (classification score of 94–100%, but it was unable to recognize the type of the movement. This is caused by the large fraction of other (nonmovement related EEG activities in the recorded signals. A classification method based on advanced EEG signal denoising is being currently developed to overcome this problem.

  11. Ultra-high resolution computed tomography imaging

    Energy Technology Data Exchange (ETDEWEB)

    Paulus, Michael J. (Knoxville, TN); Sari-Sarraf, Hamed (Knoxville, TN); Tobin, Jr., Kenneth William (Harriman, TN); Gleason, Shaun S. (Knoxville, TN); Thomas, Jr., Clarence E. (Knoxville, TN)

    2002-01-01

    A method for ultra-high resolution computed tomography imaging, comprising the steps of: focusing a high energy particle beam, for example x-rays or gamma-rays, onto a target object; acquiring a 2-dimensional projection data set representative of the target object; generating a corrected projection data set by applying a deconvolution algorithm, having an experimentally determined a transfer function, to the 2-dimensional data set; storing the corrected projection data set; incrementally rotating the target object through an angle of approximately 180.degree., and after each the incremental rotation, repeating the radiating, acquiring, generating and storing steps; and, after the rotating step, applying a cone-beam algorithm, for example a modified tomographic reconstruction algorithm, to the corrected projection data sets to generate a 3-dimensional image. The size of the spot focus of the beam is reduced to not greater than approximately 1 micron, and even to not greater than approximately 0.5 microns.

  12. Investigation of the vestibular aqueduct and the cochlear aqueduct by temporal bone CT scan

    Energy Technology Data Exchange (ETDEWEB)

    Shimizu, Ryuichi; Kamei, Tamio; Ito, Fumihide (Gunma Univ., Maebashi (Japan). School of Medicine)

    1984-02-01

    The visualization of the vestibular aqueduct and the cochlear aqueduct was investigated by temporal bone CT scan. The vestibular aqueduct was visualized in horizontal CT sections of 70.0% of normal ears, 61.5% of ears with chronic otitis media, 58.3% of ears with combined hearing impairment, 66.7% of ears in cases of sudden deafness, 70.8% of ears of patients with sensorineural hearing impairment without sudden deafness, 71.4% of cases of vertigo without hearing impairment and 12.5% of both diseased and contralateral ears of patients with Meniere's disease. Only in Meniere's disease was the vestibular aqueduct less visible in the diseased than in the normal ear (P<0.01). The cochlear aqueduct was visible in coronal sections of 50.0% of normal ears, 76.9% of those with chronic otitis media, 58.3% of those with combined hearing impairment, 66.7% of those with sudden deafness 41.7% of those with sensorineural hearing impairment without sudden deafness, 50.0% of the diseased ears of patients with Meniere's disease, 37.5% of the contralateral ears of those with Meniere's disease and 64.3% of those with vertigo without hearing impairment. Although the cochlear aqueduct was thus highly demonstrable in patients with chronic otitis media or sudden deafness, the difference between the percentage of visualization in these diseased and in normal ears was not statistically significant.

  13. A modified preauricular-temporal approach for fixing comminuted and redisplaced zygomatic arch fractures with the resorbable bone plate

    Institute of Scientific and Technical Information of China (English)

    CHEN Peng; LIU Bing; ZHANG Hai-zhong; BU Jing-qiu

    2012-01-01

    Objective: To evaluate the effectiveness of the rigid internal fixation for comminuted and redisplaced zygomatic arch fractures by modified preauricular-temporal approach with the resorbable bone fixation.Methods: Totally twenty patients aged from 14 to 68 years and admitted to our hospital between September 2006 and June 2011 were reviewed,of whom seventeen had a unilateral comminuted zygomatic arch fracture and three redisplaced arch fracture after failed closed reduction.The fracture segments were aligned to restore the preinjury form of the arch by rigid fixation with resorbable plates and screws through a modified preauricular-temporal incision.Results: The fractures were well reduced,preauricular-temporal scar and lateral facial contour were aesthetically satisfying,and no case had limited mouth opening as well as facial palsy.The resorbable plates were not palpated one year after the operation.Conclusion: The rigid internal fixation through the preauricular-temporal approach with the resorbable bone is an effective method for the comminuted and redisplaced zygomatic arch fractures.

  14. High-resolution transcriptome of human macrophages.

    Directory of Open Access Journals (Sweden)

    Marc Beyer

    Full Text Available Macrophages are dynamic cells integrating signals from their microenvironment to develop specific functional responses. Although, microarray-based transcriptional profiling has established transcriptional reprogramming as an important mechanism for signal integration and cell function of macrophages, current knowledge on transcriptional regulation of human macrophages is far from complete. To discover novel marker genes, an area of great need particularly in human macrophage biology but also to generate a much more thorough transcriptome of human M1- and M1-like macrophages, we performed RNA sequencing (RNA-seq of human macrophages. Using this approach we can now provide a high-resolution transcriptome profile of human macrophages under classical (M1-like and alternative (M2-like polarization conditions and demonstrate a dynamic range exceeding observations obtained by previous technologies, resulting in a more comprehensive understanding of the transcriptome of human macrophages. Using this approach, we identify important gene clusters so far not appreciated by standard microarray techniques. In addition, we were able to detect differential promoter usage, alternative transcription start sites, and different coding sequences for 57 gene loci in human macrophages. Moreover, this approach led to the identification of novel M1-associated (CD120b, TLR2, SLAMF7 as well as M2-associated (CD1a, CD1b, CD93, CD226 cell surface markers. Taken together, these data support that high-resolution transcriptome profiling of human macrophages by RNA-seq leads to a better understanding of macrophage function and will form the basis for a better characterization of macrophages in human health and disease.

  15. Pyramidal fractal dimension for high resolution images

    Science.gov (United States)

    Mayrhofer-Reinhartshuber, Michael; Ahammer, Helmut

    2016-07-01

    Fractal analysis (FA) should be able to yield reliable and fast results for high-resolution digital images to be applicable in fields that require immediate outcomes. Triggered by an efficient implementation of FA for binary images, we present three new approaches for fractal dimension (D) estimation of images that utilize image pyramids, namely, the pyramid triangular prism, the pyramid gradient, and the pyramid differences method (PTPM, PGM, PDM). We evaluated the performance of the three new and five standard techniques when applied to images with sizes up to 8192 × 8192 pixels. By using artificial fractal images created by three different generator models as ground truth, we determined the scale ranges with minimum deviations between estimation and theory. All pyramidal methods (PM) resulted in reasonable D values for images of all generator models. Especially, for images with sizes ≥1024 ×1024 pixels, the PMs are superior to the investigated standard approaches in terms of accuracy and computation time. A measure for the possibility to differentiate images with different intrinsic D values did show not only that the PMs are well suited for all investigated image sizes, and preferable to standard methods especially for larger images, but also that results of standard D estimation techniques are strongly influenced by the image size. Fastest results were obtained with the PDM and PGM, followed by the PTPM. In terms of absolute D values best performing standard methods were magnitudes slower than the PMs. Concluding, the new PMs yield high quality results in short computation times and are therefore eligible methods for fast FA of high-resolution images.

  16. Evaluation of the temporal bone malformations by HRCT in 17 patients with Treacher Collins Syndrome

    Energy Technology Data Exchange (ETDEWEB)

    Chihara, Yasuhiro [Kanto Medical Center NTT EC, Tokyo (Japan); Takegoshi, Hideki [Saitama Medical School, Moroyama (Japan); Kaga, Kimitaka [Tokyo Univ. (Japan). Faculty of Medicine

    2003-05-01

    Patients with Treacher Collins Syndrome have severe middle ear malformations. We have studied high-resolution computed tomography (HRCT) of seventeen patients with Treacher Collins Syndrome by using Jahrsdoerfer's grading system. Four patients underwent canalplasty. The appearance of the auricle (which we evaluated by using Marx's grading system) was correlated with the development of the middle ear in patients with Treacher Collins Syndrome. The four cases who underwent canalplasty were using a canal type hearing aid. (author)

  17. High resolution computed tomography for malformations of the cochlear and vestibular organs

    Energy Technology Data Exchange (ETDEWEB)

    Koester, O.; Straehler-Pohl, H.J.; Kim, K.H.

    1987-07-01

    Twenty-one patients with congenital deformities of the petrous bones were examined by high resolution computed tomography. This allows an accurate description of the extent of the malformation in all parts of the cochlear and vestibular organs; only localised changes in the auditory ossicles, such as fixation of the stapes and changes in the soft tissue portions of the labyrinth, cannot be shown. Improved demonstration of soft tissues while using less radiation makes high resolution CT preferable to conventional polytomography. It is also easier to perform and provides axial projections which are essential for the elucidation of malformations of the middle and inner ear.

  18. Superconducting High Resolution Fast-Neutron Spectrometers

    Energy Technology Data Exchange (ETDEWEB)

    Hau, Ionel Dragos [Univ. of California, Berkeley, CA (United States)

    2006-01-01

    Superconducting high resolution fast-neutron calorimetric spectrometers based on 6LiF and TiB{sub 2} absorbers have been developed. These novel cryogenic spectrometers measure the temperature rise produced in exothermal (n, α) reactions with fast neutrons in 6Li and 10B-loaded materials with heat capacity C operating at temperatures T close to 0.1 K. Temperature variations on the order of 0.5 mK are measured with a Mo/Cu thin film multilayer operated in the transition region between its superconducting and its normal state. The advantage of calorimetry for high resolution spectroscopy is due to the small phonon excitation energies kBT on the order of μeV that serve as signal carriers, resulting in an energy resolution ΔE ~ (kBT2C)1/2, which can be well below 10 keV. An energy resolution of 5.5 keV has been obtained with a Mo/Cu superconducting sensor and a TiB2 absorber using thermal neutrons from a 252Cf neutron source. This resolution is sufficient to observe the effect of recoil nuclei broadening in neutron spectra, which has been related to the lifetime of the first excited state in 7Li. Fast-neutron spectra obtained with a 6Li-enriched LiF absorber show an energy resolution of 16 keV FWHM, and a response in agreement with the 6Li(n, α)3H reaction cross section and Monte Carlo simulations for energies up to several MeV. The energy resolution of order of a few keV makes this novel instrument applicable to fast-neutron transmission spectroscopy based on the unique elemental signature provided by the neutron absorption and scattering resonances. The optimization of the energy resolution based on analytical and numerical models of the detector response is discussed in the context of these applications.

  19. Crusta: Visualizing High-resolution Global Data

    Science.gov (United States)

    Bernardin, T. S.; Kreylos, O.; Bowles, C. J.; Cowgill, E.; Hamann, B.; Kellogg, L. H.

    2009-12-01

    Virtual globes have become indispensable tools for visualizing, understanding and presenting data from Earth and other planetary bodies. The scientific community has invested much effort into exploiting existing globes to their fullest potential by refining and adapting their capabilities to better satisfy specific needs. For example, Google Earth provides users with the ability to view hillshade images derived from airborne LiDAR data such as the 2007 Northern California GeoEarthScope data. However, because most available globes were not designed with the specific needs of geoscientists in mind, shortcomings are becoming increasingly evident in geoscience applications such as terrain visualization. In particular, earth scientists struggle to visualize digital elevation models with both high spatial resolution (0.5 - 1 square meters per sample) and large extent (>2000 square kilometers), such as those obtained with airborne LiDAR. To address the specific earth science need of real-time terrain visualization of LiDAR data, we are developing Crusta as part of a close collaboration involving earth and computer scientists. Crusta is a new virtual globe that differs from widely used globes by both providing accurate global data representation and the ability to easily visualize custom topographic and image data. As a result, Crusta enables real-time, interactive visualization of high resolution digital elevation data spanning thousands of square kilometers, such as the complete 2007 Northern California GeoEarthScope airborne LiDAR data set. To implement an accurate data representation and avoid distortion of the display at the poles, where other projections have singularities, Crusta represents the globe as a thirty-sided polyhedron. Each side of this polyhedron can be subdivided to an arbitrarily fine grid on the surface of the globe, which allows Crusta to accommodate input data of arbitrary resolution ranging from global (e.g., Blue Marble) to local (e.g., a tripod

  20. Spatial Ensemble Postprocessing of Precipitation Forecasts Using High Resolution Analyses

    Science.gov (United States)

    Lang, Moritz N.; Schicker, Irene; Kann, Alexander; Wang, Yong

    2017-04-01

    Ensemble prediction systems are designed to account for errors or uncertainties in the initial and boundary conditions, imperfect parameterizations, etc. However, due to sampling errors and underestimation of the model errors, these ensemble forecasts tend to be underdispersive, and to lack both reliability and sharpness. To overcome such limitations, statistical postprocessing methods are commonly applied to these forecasts. In this study, a full-distributional spatial post-processing method is applied to short-range precipitation forecasts over Austria using Standardized Anomaly Model Output Statistics (SAMOS). Following Stauffer et al. (2016), observation and forecast fields are transformed into standardized anomalies by subtracting a site-specific climatological mean and dividing by the climatological standard deviation. Due to the need of fitting only a single regression model for the whole domain, the SAMOS framework provides a computationally inexpensive method to create operationally calibrated probabilistic forecasts for any arbitrary location or for all grid points in the domain simultaneously. Taking advantage of the INCA system (Integrated Nowcasting through Comprehensive Analysis), high resolution analyses are used for the computation of the observed climatology and for model training. The INCA system operationally combines station measurements and remote sensing data into real-time objective analysis fields at 1 km-horizontal resolution and 1 h-temporal resolution. The precipitation forecast used in this study is obtained from a limited area model ensemble prediction system also operated by ZAMG. The so called ALADIN-LAEF provides, by applying a multi-physics approach, a 17-member forecast at a horizontal resolution of 10.9 km and a temporal resolution of 1 hour. The performed SAMOS approach statistically combines the in-house developed high resolution analysis and ensemble prediction system. The station-based validation of 6 hour precipitation sums

  1. High-resolution EEG (HR-EEG) and magnetoencephalography (MEG).

    Science.gov (United States)

    Gavaret, M; Maillard, L; Jung, J

    2015-03-01

    High-resolution EEG (HR-EEG) and magnetoencephalography (MEG) allow the recording of spontaneous or evoked electromagnetic brain activity with excellent temporal resolution. Data must be recorded with high temporal resolution (sampling rate) and high spatial resolution (number of channels). Data analyses are based on several steps with selection of electromagnetic signals, elaboration of a head model and use of algorithms in order to solve the inverse problem. Due to considerable technical advances in spatial resolution, these tools now represent real methods of ElectroMagnetic Source Imaging. HR-EEG and MEG constitute non-invasive and complementary examinations, characterized by distinct sensitivities according to the location and orientation of intracerebral generators. In the presurgical assessment of drug-resistant partial epilepsies, HR-EEG and MEG can characterize and localize interictal activities and thus the irritative zone. HR-EEG and MEG often yield significant additional data that are complementary to other presurgical investigations and particularly relevant in MRI-negative cases. Currently, the determination of the epileptogenic zone and functional brain mapping remain rather less well-validated indications. In France, in 2014, HR-EEG is now part of standard clinical investigation of epilepsy, while MEG remains a research technique.

  2. A three-dimensional reconstruction of the temporal bone by the helical scanning CT and its clinical application

    Energy Technology Data Exchange (ETDEWEB)

    Yonekawa, Hiroyuki; Ohashi, Masami; Miyashita, Souji; Gotoh, Mizuho; Nemoto, Satohiko; Kikuchi, Hideki (Azabu Triology Hospital, Sapporo (Japan)); Sakai, Noboru; Inuyama, Yukio

    1993-09-01

    The current availability of 3 dimensional (3-D) imaging from Computed Tomography (CT) has yielded new anatomical information and pre- and postoperative evaluations. However, little discussion as to the 3-D structural image of the temporal bone has been reported because conventional CT does provide sufficient data to produce such images. The helical scanning CT gathers continuous and multiple slice image data since it consists of an X-ray tube that continuously rotates around the patient while the patient moves continuously into the CT scanner. Thus, application of the helical scanning CT has made it possible to reconstruct 3-D images of the minute and complicated structure of the temporal bone. We evaluated 3-D images from 9 typical cases, examined from February to October 1992. As a result, we found that the 3-D images reconstructed with this system are useful for evaluation of the postoperative state of tympanoplasty, the diagnosis of anomalies of the bony labyrinth, and examining the extent of bone destruction induced by trauma, cholesteatoma, etc. (author).

  3. 颞骨骨折导致的双侧周围性面瘫%Facial Nerve Decompression for Bilateral Facial Paralysis in Temporal Bone Fracture

    Institute of Scientific and Technical Information of China (English)

    李晓红; 刘菲; 王若雅; 韩维举

    2014-01-01

    Objective The purpose of this rieview is to study management of bilateral facial nerve paralysis in temporal bone fracture. Methods This is a retrospective review of 8 cases of bilateral facial paralysis after bilateral temporal bone frac-ture that were treated with facial nerve decompression on at least one side. High-resolution computed tomography, audiomet-rictests and electromyogram (EMG) were obtained. Evaluation of the facial nerve function according to the House-Brackmann (H-B) grading scale. The decision for surgery was based mainly on the results of afore mentioned evaluations. Timing and the efficacy of surgical intervention were evaluated by pre-vs. post-operative facial nerve function assessments, as well as com-parison between the operation side and the opposite side. Results All the 8 patients were male, aged between 19 and 49 years. Traffic accident was the most commom cause (5/8). Fracture was longitudinal in all 16 temporal bones, with immediate onset of facial paralysis. Preoperative facial nerve function is between gradesⅤ and Ⅵ, in H-B scale, and with l patient showing bilateral conductive hearing loss, 4 Ratients showing bilateral lugh-frequency sensorineural deafness and 3 Ratients showing normal hearing. Among 8 patients, Facial nerve decompression was performed in 11 ears. H-B gradeⅠ-Ⅱfacial nerve function were aclueved in all cases at follow up (more than l year in some). The only patient with bilateral conductive hearing loss also received bilateral ossicular reconstruction, followed by recovery to normal hearing. Conclusions Traffic crash continues to be themain cause of temporal bone fracture and hilaterd faial paralysis and hilaterd faial paralysis. Facial paralysis caused by tempo-ral bone trauma can be satisfactorily treated with decompression.%目的:探讨外伤后双侧颞骨纵形骨折致双侧周围性面瘫行面神经减压手术的适应症、手术时机及疗效。方法回顾性收集外伤后双侧颞骨骨折

  4. Logging Data High-Resolution Sequence Stratigraphy

    Institute of Scientific and Technical Information of China (English)

    Li Hongqi; Xie Yinfu; Sun Zhongchun; Luo Xingping

    2006-01-01

    The recognition and contrast of bed sets in parasequence is difficult in terrestrial basin high-resolution sequence stratigraphy. This study puts forward new methods for the boundary identification and contrast of bed sets on the basis of manifold logging data. The formation of calcareous interbeds, shale resistivity differences and the relation of reservoir resistivity to altitude are considered on the basis of log curve morphological characteristics, core observation, cast thin section, X-ray diffraction and scanning electron microscopy. The results show that the thickness of calcareous interbeds is between 0.5 m and 2 m, increasing on weathering crusts and faults. Calcareous interbeds occur at the bottom of Reservoir resistivity increases with altitude. Calcareous interbeds may be a symbol of recognition for the boundary of bed sets and isochronous contrast bed sets, and shale resistivity differences may confirm the stack relation and connectivity of bed sets. Based on this, a high-rcsolution chronostratigraphic framework of Xi-1 segment in Shinan area, Junggar basin is presented, and the connectivity of bed sets and oil-water contact is confirmed. In this chronostratigraphic framework, the growth order, stack mode and space shape of bed sets are qualitatively and quantitatively described.

  5. AIRBORNE HIGH-RESOLUTION DIGITAL IMAGING SYSTEM

    Directory of Open Access Journals (Sweden)

    Prado-Molina, J.

    2006-04-01

    Full Text Available A low-cost airborne digital imaging system capable to perform aerial surveys with small-format cameras isintroduced. The equipment is intended to obtain high-resolution multispectral digital photographs constituting so aviable alternative to conventional aerial photography and satellite imagery. Monitoring software handles all theprocedures involved in image acquisition, including flight planning, real-time graphics for aircraft position updatingin a mobile map, and supervises the main variables engaged in the imaging process. This software also creates fileswith the geographical position of the central point of every image, and the flight path followed by the aircraftduring the entire survey. The cameras are mounted on a three-axis stabilized platform. A set of inertial sensorsdetermines platform's deviations independently from the aircraft and an automatic control system keeps thecameras at a continuous nadir pointing and heading, with a precision better than ± 1 arc-degree in three-axis. Thecontrol system is also in charge of saving the platform’s orientation angles when the monitoring software triggersthe camera. These external orientation parameters, together with a procedure for camera calibration give theessential elements for image orthocorrection. Orthomosaics are constructed using commercial GIS software.This system demonstrates the feasibility of large area coverage in a practical and economical way using smallformatcameras. Monitoring and automatization reduce the work while increasing the quality and the amount ofuseful images.

  6. Radiation length imaging with high resolution telescopes

    CERN Document Server

    Stolzenberg, U; Schwenker, B; Wieduwilt, P; Marinas, C; Lütticke, F

    2016-01-01

    The construction of low mass vertex detectors with a high level of system integration is of great interest for next generation collider experiments. Radiation length images with a sufficient spatial resolution can be used to measure and disentangle complex radiation length $X$/$X_0$ profiles and contribute to the understanding of vertex detector systems. Test beam experiments with multi GeV particle beams and high-resolution tracking telescopes provide an opportunity to obtain precise 2D images of the radiation length of thin planar objects. At the heart of the $X$/$X_0$ imaging is a spatially resolved measurement of the scattering angles of particles traversing the object under study. The main challenges are the alignment of the reference telescope and the calibration of its angular resolution. In order to demonstrate the capabilities of $X$/$X_0$ imaging, a test beam experiment has been conducted. The devices under test were two mechanical prototype modules of the Belle II vertex detector. A data sample of ...

  7. High-resolution light microscopy of nanoforms

    Science.gov (United States)

    Vodyanoy, Vitaly; Pustovyy, Oleg; Vainrub, Arnold

    2007-09-01

    We developed a high resolution light imaging system. Diffraction gratings with 100 nm width lines as well as less than 100 nm size features of different-shaped objects are clearly visible on a calibrated microscope test slide (Vainrub et al., Optics Letters, 2006, 31, 2855). The two-point resolution increase results from a known narrowing of the central diffraction peak for the annular aperture. Better visibility and advanced contrast of the smallest features in the image are due to enhancement of high spatial frequencies in the optical transfer function. The imaging system is portable, low energy, and battery operated. It has been adapted to use in both transmitting and reflecting light. It is particularly applicable for motile nanoform systems where structure and functions can be depicted in real time. We have isolated micrometer and submicrometer particles, termed proteons, from human and animal blood. Proteons form by reversible seeded aggregation of proteins around proteon nucleating centers (PNCs). PNCs are comprised of 1-2nm metallic nanoclusters containing 40-300 atoms. Proteons are capable of spontaneous assembling into higher nanoform systems assuming structure of complicated topology. The arrangement of complex proteon system mimics the structure of a small biological cell. It has structures that imitate membrane and nucleolus or nuclei. Some of these nanoforms are motile. They interact and divide. Complex nanoform systems can spontaneously reduce to simple proteons. The physical properties of these nanoforms could shed some light on the properties of early life forms or forms at extreme conditions.

  8. Automatic abundance analysis of high resolution spectra

    CERN Document Server

    Bonifacio, P; Bonifacio, Piercarlo; Caffau, Elisabetta

    2003-01-01

    We describe an automatic procedure for determining abundances from high resolution spectra. Such procedures are becoming increasingly important as large amounts of data are delivered from 8m telescopes and their high-multiplexing fiber facilities, such as FLAMES on ESO-VLT. The present procedure is specifically targeted for the analysis of spectra of giants in the Sgr dSph; however, the procedure may be, in principle, tailored to analyse stars of any type. Emphasis is placed on the algorithms and on the stability of the method; the external accuracy rests, ultimately, on the reliability of the theoretical models (model-atmospheres, synthetic spectra) used to interpret the data. Comparison of the results of the procedure with the results of a traditional analysis for 12 Sgr giants shows that abundances accurate at the level of 0.2 dex, comparable with that of traditional analysis of the same spectra, may be derived in a fast and efficient way. Such automatic procedures are not meant to replace the traditional ...

  9. High Resolution Radar Measurements of Snow Avalanches

    Science.gov (United States)

    McElwaine, Jim; Sovilla, Betty; Vriend, Nathalie; Brennan, Paul; Ash, Matt; Keylock, Chris

    2013-04-01

    Geophysical mass flows, such as snow avalanches, are a major hazard in mountainous areas and have a significant impact on the infrastructure, economy and tourism of such regions. Obtaining a thorough understanding of the dynamics of snow avalanches is crucial for risk assessment and the design of defensive structures. However, because the underlying physics is poorly understood there are significant uncertainties concerning current models, which are poorly validated due to a lack of high resolution data. Direct observations of the denser core of a large avalanche are particularly difficult, since it is frequently obscured by the dilute powder cloud. We have developed and installed a phased array FMCW radar system that penetrates the powder cloud and directly images the dense core with a resolution of around 1 m at 50 Hz over the entire slope. We present data from recent avalanches at Vallee de la Sionne that show a wealth of internal structure and allow the tracking of individual fronts, roll waves and surges down the slope for the first time. We also show good agreement between the radar results and existing measurement systems that record data at particular points on the avalanche track.

  10. Holographic high-resolution endoscopic image recording

    Science.gov (United States)

    Bjelkhagen, Hans I.

    1991-03-01

    Endoscopic holography or endoholography combines the features of endoscopy and holography. The purpose of endoholographic imaging is to provide the physician with a unique means of extending diagnosis by providing a life-like record of tissue. Endoholographic recording will provide means for microscopic examination of tissue and in some cases may obviate the need to excise specimens for biopsy. In this method holograms which have the unique properties of three-dimensionality large focal depth and high resolution are made with a newly designed endoscope. The endoscope uses a single-mode optical fiber for illumination and single-beam reflection holograms are recorded in close contact with the tissue at the distal end of the endoscope. The holograms are viewed under a microscope. By using the proper combinations of dyes for staining specific tissue types with various wavelengths of laser illumination increased contrast on the cellular level can be obtained. Using dyes such as rose bengal in combination with the 514. 5 nm line of an argon ion laser and trypan blue or methylene blue with the 647. 1 nm line of a krypton ion laser holograms of the stained colon of a dog showed the architecture of the colon''s columnar epithelial cells. It is hoped through chronological study using this method in-vivo an increased understanding of the etiology and pathology of diseases such as Crohn''s diseases colitis proctitis and several different forms of cancer will help

  11. High-resolution imaging using endoscopic holography

    Science.gov (United States)

    Bjelkhagen, Hans I.

    1990-08-01

    Endoscopic holography or endoholography combines the features of endoscopy and holography. The purpose of endoholographic imaging is to provide the physician with a unique means of extending diagnosis by providing a life-like record of tissue. Endoholographic recording will provide means for microscopic examination of tissue and in some cases may obviate the need to excise specimens for biopsy. In this method holograms which have the unique properties of three-dimensionality large focal depth and high resolution are made with a newly designed endoscope. The endoscope uses a single-mode optical fiber for illumination and single-beam reflection holograms are recorded in close contact with the tissue at the distal end of the endoscope. The holograms are viewed under a microscope. By using the proper combinations of dyes for staining specific tissue types with various wavelengths of laser illumination increased contrast on the cellular level can be obtained. Using dyes such as rose bengal in combination with the 514. 5 nm line of an argon ion laser and trypan blue or methylene blue with the 647. 1 nm line of a krypton ion laser holograms of the stained colon of a dog showed the architecture of the colon''s columnar epithelial cells. It is hoped through chronological study using this method in-vivo an increased understanding of the etiology and pathology of diseases such as Crohn''s diseases colitis proctitis and several different forms of cancer will help to their control. 1.

  12. Supporting observation campaigns with high resolution modeling

    Science.gov (United States)

    Klocke, Daniel; Brueck, Matthias; Voigt, Aiko

    2017-04-01

    High resolution simulation in support of measurement campaigns offers a promising and emerging way to create large-scale context for small-scale observations of clouds and precipitation processes. As these simulation include the coupling of measured small-scale processes with the circulation, they also help to integrate the research communities from modeling and observations and allow for detailed model evaluations against dedicated observations. In connection with the measurement campaign NARVAL (August 2016 and December 2013) simulations with a grid-spacing of 2.5 km for the tropical Atlantic region (9000x3300 km), with local refinement to 1.2 km for the western part of the domain, were performed using the icosahedral non-hydrostatic (ICON) general circulation model. These simulations are again used to drive large eddy resolving simulations with the same model for selected days in the high definition clouds and precipitation for advancing climate prediction (HD(CP)2) project. The simulations are presented with the focus on selected results showing the benefit for the scientific communities doing atmospheric measurements and numerical modeling of climate and weather. Additionally, an outlook will be given on how similar simulations will support the NAWDEX measurement campaign in the North Atlantic and AC3 measurement campaign in the Arctic.

  13. Laser wavelength comparison by high resolution interferometry.

    Science.gov (United States)

    Layer, H P; Deslattes, R D; Schweitzer, W G

    1976-03-01

    High resolution interferometry has been used to determine the wavelength ratio between two molecularly stabilized He-Ne lasers, one locked to a methane absorption at 3.39 microm and the other locked to the k peak of (129)I(2) at 633 nm. An optical beat frequency technique gave fractional orders while a microwave sideband method yielded the integer parts. Conventional (third derivative) peak seeking servoes stabilized both laser and cavity lengths. Reproducibility of the electronic control system and optics was a few parts in 10(12), while systematic errors associated with curvature of the cavity mirrors limited the accuracy of the wavelength ratio measurement to 2 parts in 10(10). The measured wavelength ratio of the methane stabilized He-Ne laser at 3.39 microm [P(7) line, nu(3) band] to the (129)I(2) (k peak) stabilized He-Ne laser at 633 nm was 5.359 049 260 6 (0.000 2 ppm). This ratio agrees with that calculated from the (lower accuracy) results of earlier wavelength measurements made relative to the (86)Kr standard. Its higher accuracy thus permits a provisional extension of the frequency scale based on the cesium oscillator into the visible spectrum.

  14. Estudo anatômico do osso temporal de um primata não-humano (Callithrix sp Anatomical study of a temporal bone from a non-human primate (Callithrix sp

    Directory of Open Access Journals (Sweden)

    Andrei Borin

    2008-06-01

    Full Text Available A busca por modelos experimentais constitui passo fundamental para o avanço da medicina. OBJETIVO: Demonstrar, através da dissecção com técnicas microcirúrgicas, as estruturas anatômicas do osso temporal do primata Callithrix sp. FORMA DE ESTUDO: Experimental. MÉTODO: Dissecção de ossos temporais de Callithrix sp e documentação fotográfica. RESULTADOS: Identificamos as principais estruturas do osso temporal (orelhas externa, média e interna, e nervo facial. CONCLUSÃO: O primata não-humano Callithrix sp representa aparentemente um modelo viável para o estudo do osso temporal uma vez que apresenta alta similaridade anatômica com humanos.The search for experimental (animal models is essential to the development of clinical studies. AIM: To demonstrate, by means of micro dissection techniques, the anatomical structures of temporal bones from the primate Callithrix sp. STUDY DESIGN: Experimental. METHODS: Dissection of temporal bone structures of Callithrix sp and photographic documentation. RESULTS: We identified the main constituents of the temporal bone (external, medium and inner ear and facial nerve. CONCLUSION: The non-human primate Callithrix sp. is an adequate experimental model for the studies of temporal bone structures given its close anatomical similarities to that found in humans.

  15. The temporal expression of estrogen receptor alpha-36 and runx2 in human bone marrow derived stromal cells during osteogenesis

    Energy Technology Data Exchange (ETDEWEB)

    Francis, W.R., E-mail: w.francis@swansea.ac.uk [Institute of Life Science, College of Medicine, Swansea University (United Kingdom); Owens, S.E.; Wilde, C. [Institute of Life Science, College of Medicine, Swansea University (United Kingdom); Pallister, I. [Institute of Life Science, College of Medicine, Swansea University (United Kingdom); Trauma and Orthopaedics, Morriston Hospital, Swansea (United Kingdom); Kanamarlapudi, V. [Institute of Life Science, College of Medicine, Swansea University (United Kingdom); Zou, W., E-mail: weizou60@hotmail.com [College of Life Sciences, Liaoning Normal University, Dalian 116081 (China); Liaoning Key Laboratories of Biotechnology and Molecular Drug Research and Development, Dalian 116081 (China); Xia, Z. [Institute of Life Science, College of Medicine, Swansea University (United Kingdom)

    2014-10-24

    Highlights: • ERα36 is the predominant ERα isoform involved in bone regulation in human BMSC. • ERα36 mRNA is significantly upregulated during the process of osteogenesis. • The pattern of ERα36 and runx2 mRNA expression is similar during osteogenesis. • ERα36 appears to be co-localised with runx2 during osteogenesis. - Abstract: During bone maintenance in vivo, estrogen signals through estrogen receptor (ER)-α. The objectives of this study were to investigate the temporal expression of ERα36 and ascertain its functional relevance during osteogenesis in human bone marrow derived stromal cells (BMSC). This was assessed in relation to runt-related transcription factor-2 (runx2), a main modulatory protein involved in bone formation. ERα36 and runx2 subcellular localisation was assessed using immunocytochemistry, and their mRNA expression levels by real time PCR throughout the process of osteogenesis. The osteogenically induced BMSCs demonstrated a rise in ERα36 mRNA during proliferation followed by a decline in expression at day 10, which represents a change in dynamics within the culture between the proliferative stage and the differentiative stage. The mRNA expression profile of runx2 mirrored that of ERα36 and showed a degree subcellular co-localisation with ERα36. This study suggests that ERα36 is involved in the process of osteogenesis in BMSCs, which has implications in estrogen deficient environments.

  16. Large Scale, High Resolution, Mantle Dynamics Modeling

    Science.gov (United States)

    Geenen, T.; Berg, A. V.; Spakman, W.

    2007-12-01

    To model the geodynamic evolution of plate convergence, subduction and collision and to allow for a connection to various types of observational data, geophysical, geodetical and geological, we developed a 4D (space-time) numerical mantle convection code. The model is based on a spherical 3D Eulerian fem model, with quadratic elements, on top of which we constructed a 3D Lagrangian particle in cell(PIC) method. We use the PIC method to transport material properties and to incorporate a viscoelastic rheology. Since capturing small scale processes associated with localization phenomena require a high resolution, we spend a considerable effort on implementing solvers suitable to solve for models with over 100 million degrees of freedom. We implemented Additive Schwartz type ILU based methods in combination with a Krylov solver, GMRES. However we found that for problems with over 500 thousend degrees of freedom the convergence of the solver degraded severely. This observation is known from the literature [Saad, 2003] and results from the local character of the ILU preconditioner resulting in a poor approximation of the inverse of A for large A. The size of A for which ILU is no longer usable depends on the condition of A and on the amount of fill in allowed for the ILU preconditioner. We found that for our problems with over 5×105 degrees of freedom convergence became to slow to solve the system within an acceptable amount of walltime, one minute, even when allowing for considerable amount of fill in. We also implemented MUMPS and found good scaling results for problems up to 107 degrees of freedom for up to 32 CPU¡¯s. For problems with over 100 million degrees of freedom we implemented Algebraic Multigrid type methods (AMG) from the ML library [Sala, 2006]. Since multigrid methods are most effective for single parameter problems, we rebuild our model to use the SIMPLE method in the Stokes solver [Patankar, 1980]. We present scaling results from these solvers for 3D

  17. Potential High Resolution Dosimeters For MRT

    Science.gov (United States)

    Bräuer-Krisch, E.; Rosenfeld, A.; Lerch, M.; Petasecca, M.; Akselrod, M.; Sykora, J.; Bartz, J.; Ptaszkiewicz, M.; Olko, P.; Berg, A.; Wieland, M.; Doran, S.; Brochard, T.; Kamlowski, A.; Cellere, G.; Paccagnella, A.; Siegbahn, E. A.; Prezado, Y.; Martinez-Rovira, I.; Bravin, A.; Dusseau, L.; Berkvens, P.

    2010-07-01

    Microbeam Radiation Therapy (MRT) uses highly collimated, quasi-parallel arrays of X-ray microbeams of 50-600 keV, produced by 2nd and 3rd generation synchrotron sources, such as the National Synchrotron Light Source (NSLS) in the U.S., and the European Synchrotron Radiation Facility (ESRF) in France, respectively. High dose rates are necessary to deliver therapeutic doses in microscopic volumes, to avoid spreading of the microbeams by cardiosynchronous movement of the tissues. A small beam divergence and a filtered white beam spectrum in the energy range between 30 and 250 keV results in the advantage of steep dose gradients with a sharper penumbra than that produced in conventional radiotherapy. MRT research over the past 20 years has allowed a vast number of results from preclinical trials on different animal models, including mice, rats, piglets and rabbits. Microbeams in the range between 10 and 100 micron width show an unprecedented sparing of normal radiosensitive tissues as well as preferential damage to malignant tumor tissues. Typically, MRT uses arrays of narrow (˜25-100 micron-wide) microplanar beams separated by wider (100-400 microns centre-to-centre, c-t-c) microplanar spaces. We note that thicker microbeams of 0.1-0.68 mm used by investigators at the NSLS are still called microbeams, although some invesigators in the community prefer to call them minibeams. This report, however, limits it discussion to 25-100 μm microbeams. Peak entrance doses of several hundreds of Gy are surprisingly well tolerated by normal tissues. High resolution dosimetry has been developed over the last two decades, but typical dose ranges are adapted to dose delivery in conventional Radiation Therapy (RT). Spatial resolution in the sub-millimetric range has been achieved, which is currently required for quality assurance measurements in Gamma-knife RT. Most typical commercially available detectors are not suitable for MRT applications at a dose rate of 16000 Gy/s, micron

  18. High-resolution downscaling for hydrological management

    Science.gov (United States)

    Ulbrich, Uwe; Rust, Henning; Meredith, Edmund; Kpogo-Nuwoklo, Komlan; Vagenas, Christos

    2017-04-01

    Hydrological modellers and water managers require high-resolution climate data to model regional hydrologies and how these may respond to future changes in the large-scale climate. The ability to successfully model such changes and, by extension, critical infrastructure planning is often impeded by a lack of suitable climate data. This typically takes the form of too-coarse data from climate models, which are not sufficiently detailed in either space or time to be able to support water management decisions and hydrological research. BINGO (Bringing INnovation in onGOing water management; ) aims to bridge the gap between the needs of hydrological modellers and planners, and the currently available range of climate data, with the overarching aim of providing adaptation strategies for climate change-related challenges. Producing the kilometre- and sub-daily-scale climate data needed by hydrologists through continuous simulations is generally computationally infeasible. To circumvent this hurdle, we adopt a two-pronged approach involving (1) selective dynamical downscaling and (2) conditional stochastic weather generators, with the former presented here. We take an event-based approach to downscaling in order to achieve the kilometre-scale input needed by hydrological modellers. Computational expenses are minimized by identifying extremal weather patterns for each BINGO research site in lower-resolution simulations and then only downscaling to the kilometre-scale (convection permitting) those events during which such patterns occur. Here we (1) outline the methodology behind the selection of the events, and (2) compare the modelled precipitation distribution and variability (preconditioned on the extremal weather patterns) with that found in observations.

  19. High-resolution phylogenetic microbial community profiling

    Energy Technology Data Exchange (ETDEWEB)

    Singer, Esther; Coleman-Derr, Devin; Bowman, Brett; Schwientek, Patrick; Clum, Alicia; Copeland, Alex; Ciobanu, Doina; Cheng, Jan-Fang; Gies, Esther; Hallam, Steve; Tringe, Susannah; Woyke, Tanja

    2014-03-17

    The representation of bacterial and archaeal genome sequences is strongly biased towards cultivated organisms, which belong to merely four phylogenetic groups. Functional information and inter-phylum level relationships are still largely underexplored for candidate phyla, which are often referred to as microbial dark matter. Furthermore, a large portion of the 16S rRNA gene records in the GenBank database are labeled as environmental samples and unclassified, which is in part due to low read accuracy, potential chimeric sequences produced during PCR amplifications and the low resolution of short amplicons. In order to improve the phylogenetic classification of novel species and advance our knowledge of the ecosystem function of uncultivated microorganisms, high-throughput full length 16S rRNA gene sequencing methodologies with reduced biases are needed. We evaluated the performance of PacBio single-molecule real-time (SMRT) sequencing in high-resolution phylogenetic microbial community profiling. For this purpose, we compared PacBio and Illumina metagenomic shotgun and 16S rRNA gene sequencing of a mock community as well as of an environmental sample from Sakinaw Lake, British Columbia. Sakinaw Lake is known to contain a large age of microbial species from candidate phyla. Sequencing results show that community structure based on PacBio shotgun and 16S rRNA gene sequences is highly similar in both the mock and the environmental communities. Resolution power and community representation accuracy from SMRT sequencing data appeared to be independent of GC content of microbial genomes and was higher when compared to Illumina-based metagenome shotgun and 16S rRNA gene (iTag) sequences, e.g. full-length sequencing resolved all 23 OTUs in the mock community, while iTags did not resolve closely related species. SMRT sequencing hence offers various potential benefits when characterizing uncharted microbial communities.

  20. Radiation dose optimization in pediatric temporal bone computed tomography: influence of tube tension on image contrast and image quality

    Energy Technology Data Exchange (ETDEWEB)

    Nauer, Claude Bertrand [University Hospital Berne, Institute of Diagnostic and Interventional Neuroradiology, Berne (Switzerland); Zentrales Roentgeninstitut, Kantonsspital Graubuenden, Chur (Switzerland); Zubler, Christoph; Weisstanner, Christian [University Hospital Berne, Institute of Diagnostic and Interventional Neuroradiology, Berne (Switzerland); Stieger, Christof [University Berne, Group for Artificial Hearing Research, ARTORG Center, Berne (Switzerland); Senn, Pascal [University Hospital Berne, Department of ENT, Head and Neck Surgery, Berne (Switzerland); Arnold, Andreas [University Berne, Group for Artificial Hearing Research, ARTORG Center, Berne (Switzerland); University Hospital Berne, Department of ENT, Head and Neck Surgery, Berne (Switzerland)

    2012-03-15

    The purpose of this experimental study was to investigate the effect of tube tension reduction on image contrast and image quality in pediatric temporal bone computed tomography (CT). Seven lamb heads with infant-equivalent sizes were scanned repeatedly, using four tube tensions from 140 to 80 kV while the CT-Dose Index (CTDI) was held constant. Scanning was repeated with four CTDI values from 30 to 3 mGy. Image contrast was calculated for the middle ear as the Hounsfield unit (HU) difference between bone and air and for the inner ear as the HU difference between bone and fluid. The influence of tube tension on high-contrast detail delineation was evaluated using a phantom. The subjective image quality of eight middle and inner ear structures was assessed using a 4-point scale (scores 1-2 = insufficient; scores 3-4 = sufficient). Middle and inner ear contrast showed a near linear increase with tube tension reduction (r = -0.94/-0.88) and was highest at 80 kV. Tube tension had no influence on spatial resolution. Subjective image quality analysis showed significantly better scoring at lower tube tensions, with highest image quality at 80 kV. However, image quality improvement was most relevant for low-dose scans. Image contrast in the temporal bone is significantly higher at low tube tensions, leading to a better subjective image quality. Highest contrast and best quality were found at 80 kV. This image quality improvement might be utilized to further reduce the radiation dose in pediatric low-dose CT protocols. (orig.)

  1. High-resolution global irradiance monitoring from photovoltaic systems

    Science.gov (United States)

    Buchmann, Tina; Pfeilsticker, Klaus; Siegmund, Alexander; Meilinger, Stefanie; Mayer, Bernhard; Pinitz, Sven; Steinbrecht, Wolfgang

    2016-04-01

    Reliable and regional differentiated power forecasts are required to guarantee an efficient and economic energy transition towards renewable energies. Amongst other renewable energy technologies, e.g. wind mills, photovoltaic systems are an essential component of this transition being cost-efficient and simply to install. Reliable power forecasts are however required for a grid integration of photovoltaic systems, which among other data requires high-resolution spatio-temporal global irradiance data. Hence the generation of robust reviewed global irradiance data is an essential contribution for the energy transition. To achieve this goal our studies introduce a novel method which makes use of photovoltaic power generation in order to infer global irradiance. The method allows to determine high-resolution temporal global irradiance data (one data point every 15 minutes at each location) from power data of operated photovoltaic systems. Due to the multitude of installed photovoltaic systems (in Germany) the detailed spatial coverage is much better than for example only using global irradiance data from conventional pyranometer networks (e.g. from the German Weather Service). Our designated method is composed of two components: a forward component, i.e. to conclude from predicted global irradiance to photovoltaic (PV) power, and a backward component, i.e. from PV power with suitable calibration to global irradiance. The forward process is modelled by using the radiation transport model libRadtran (B. Mayer and A. Kylling (1)) for clear skies to obtain the characteristics (orientation, size, temperature dependence, …) of individual PV systems. For PV systems in the vicinity of a meteorological station, these data are validated against calibrated pyranometer readings. The forward-modelled global irradiance is used to determine the power efficiency for each photovoltaic system using non-linear optimisation techniques. The backward component uses the power efficiency

  2. High resolution modeling of a small urban catchment

    Science.gov (United States)

    Skouri-Plakali, Ilektra; Ichiba, Abdellah; Gires, Auguste; Tchiguirinskaia, Ioulia; Schertzer, Daniel

    2016-04-01

    Flooding is one of the most complex issues that urban environments have to deal with. In France, flooding remains the first natural risk with 72% of decrees state of natural disaster issued between October 1982 and mid-November 2014. Flooding is a result of meteorological extremes that are usually aggravated by the hydrological behavior of urban catchments and human factors. The continuing urbanization process is indeed changing the whole urban water cycle by limiting the infiltration and promoting runoff. Urban environments are very complex systems due to their extreme variability, the interference between human activities and natural processes but also the effect of the ongoing urbanization process that changes the landscape and hardly influences their hydrologic behavior. Moreover, many recent works highlight the need to simulate all urban water processes at their specific temporal and spatial scales. However, considering urban catchments heterogeneity still challenging for urban hydrology, even after advances noticed in term of high-resolution data collection and computational resources. This issue is more to be related to the architecture of urban models being used and how far these models are ready to take into account the extreme variability of urban catchments. In this work, high spatio-temporal resolution modeling is performed for a small and well-equipped urban catchment. The aim of this work is to identify urban modeling needs in terms of spatial and temporal resolution especially for a very small urban area (3.7 ha urban catchment located in the Perreux-sur-Marne city at the southeast of Paris) MultiHydro model was selected to carry out this work, it is a physical based and fully distributed model that interacts four existing modules each of them representing a portion of the water cycle in urban environments. MultiHydro was implemented at 10m, 5m and 2m resolution. Simulations were performed at different spatio-temporal resolutions and analyzed with

  3. Two developmentally temporal quantitative trait loci underlie convergent evolution of increased branchial bone length in sticklebacks.

    Science.gov (United States)

    Erickson, Priscilla A; Glazer, Andrew M; Cleves, Phillip A; Smith, Alyson S; Miller, Craig T

    2014-08-07

    In convergent evolution, similar phenotypes evolve repeatedly in independent populations, often reflecting adaptation to similar environments. Understanding whether convergent evolution proceeds via similar or different genetic and developmental mechanisms offers insight towards the repeatability and predictability of evolution. Oceanic populations of threespine stickleback fish, Gasterosteus aculeatus, have repeatedly colonized countless freshwater lakes and streams, where new diets lead to morphological adaptations related to feeding. Here, we show that heritable increases in branchial bone length have convergently evolved in two independently derived freshwater stickleback populations. In both populations, an increased bone growth rate in juveniles underlies the convergent adult phenotype, and one population also has a longer cartilage template. Using F2 crosses from these two freshwater populations, we show that two quantitative trait loci (QTL) control branchial bone length at distinct points in development. In both populations, a QTL on chromosome 21 controls bone length throughout juvenile development, and a QTL on chromosome 4 controls bone length only in adults. In addition to these similar developmental profiles, these QTL show similar chromosomal locations in both populations. Our results suggest that sticklebacks have convergently evolved longer branchial bones using similar genetic and developmental programmes in two independently derived populations. © 2014 The Author(s) Published by the Royal Society. All rights reserved.

  4. High Resolution Airborne Shallow Water Mapping

    Science.gov (United States)

    Steinbacher, F.; Pfennigbauer, M.; Aufleger, M.; Ullrich, A.

    2012-07-01

    In order to meet the requirements of the European Water Framework Directive (EU-WFD), authorities face the problem of repeatedly performing area-wide surveying of all kinds of inland waters. Especially for mid-sized or small rivers this is a considerable challenge imposing insurmountable logistical efforts and costs. It is therefore investigated if large-scale surveying of a river system on an operational basis is feasible by employing airborne hydrographic laser scanning. In cooperation with the Bavarian Water Authority (WWA Weilheim) a pilot project was initiated by the Unit of Hydraulic Engineering at the University of Innsbruck and RIEGL Laser Measurement Systems exploiting the possibilities of a new LIDAR measurement system with high spatial resolution and high measurement rate to capture about 70 km of riverbed and foreland for the river Loisach in Bavaria/Germany and the estuary and parts of the shoreline (about 40km in length) of lake Ammersee. The entire area surveyed was referenced to classic terrestrial cross-section surveys with the aim to derive products for the monitoring and managing needs of the inland water bodies forced by the EU-WFD. The survey was performed in July 2011 by helicopter and airplane and took 3 days in total. In addition, high resolution areal images were taken to provide an optical reference, offering a wide range of possibilities on further research, monitoring, and managing responsibilities. The operating altitude was about 500 m to maintain eye-safety, even for the aided eye, the airspeed was about 55 kts for the helicopter and 75 kts for the aircraft. The helicopter was used in the alpine regions while the fixed wing aircraft was used in the plains and the urban area, using appropriate scan rates to receive evenly distributed point clouds. The resulting point density ranged from 10 to 25 points per square meter. By carefully selecting days with optimum water quality, satisfactory penetration down to the river bed was achieved

  5. Spiral and vestibular ganglion estimates in archival temporal bones obtained by design based stereology and Abercrombie methods.

    Science.gov (United States)

    Ishiyama, Gail; Geiger, Christopher; Lopez, Ivan A; Ishiyama, Akira

    2011-03-15

    The objective of this study was to make direct comparisons of the estimates of spiral and vestibular neuronal number in human archival temporal bone specimens using design-based stereology with those using the assumption-based Abercrombie method. Archival human temporal bone specimens from subjects ranging in age from 16 to 80 years old were used. The number of spiral and vestibular ganglia neurons within the counting areas was estimated using the stereology-optical disector technique and compared with estimates obtained using the assumption-based Abercrombie method on the same specimens. Using the optical disector method, there was an average of 41,480 (coefficient of variation=0.12) spiral ganglia neurons and 28,930 (coefficient of variation=0.15) vestibular ganglia neurons. The mean coefficient of error was 0.076 for the spiral ganglion estimates, and 0.091 for the vestibular ganglion estimates. Using the Abercrombie correction method of two-dimensional analysis, an average of 23,110 (coefficient of variation of 0.08) spiral ganglia neurons, and 16,225 vestibular ganglia neurons (coefficient of variation of 0.15) was obtained. We found that there was a large disparity between the estimates with a significant 44% underestimation of the spiral and vestibular ganglion counts obtained using the Abercrombie method when compared with estimates using the optical disector method.

  6. A dynamic aerodynamic resistance approach to calculate high resolution sensible heat fluxes in urban areas

    Science.gov (United States)

    Crawford, Ben; Grimmond, Sue; Kent, Christoph; Gabey, Andrew; Ward, Helen; Sun, Ting; Morrison, William

    2017-04-01

    Remotely sensed data from satellites have potential to enable high-resolution, automated calculation of urban surface energy balance terms and inform decisions about urban adaptations to environmental change. However, aerodynamic resistance methods to estimate sensible heat flux (QH) in cities using satellite-derived observations of surface temperature are difficult in part due to spatial and temporal variability of the thermal aerodynamic resistance term (rah). In this work, we extend an empirical function to estimate rah using observational data from several cities with a broad range of surface vegetation land cover properties. We then use this function to calculate spatially and temporally variable rah in London based on high-resolution (100 m) land cover datasets and in situ meteorological observations. In order to calculate high-resolution QH based on satellite-observed land surface temperatures, we also develop and employ novel methods to i) apply source area-weighted averaging of surface and meteorological variables across the study spatial domain, ii) calculate spatially variable, high-resolution meteorological variables (wind speed, friction velocity, and Obukhov length), iii) incorporate spatially interpolated urban air temperatures from a distributed sensor network, and iv) apply a modified Monte Carlo approach to assess uncertainties with our results, methods, and input variables. Modeled QH using the aerodynamic resistance method is then compared to in situ observations in central London from a unique network of scintillometers and eddy-covariance measurements.

  7. High-resolution noncontact atomic force microscopy.

    Science.gov (United States)

    Pérez, Rubén; García, Ricardo; Schwarz, Udo

    2009-07-01

    original papers authored by many of the leading groups in the field with the goal of providing a well-balanced overview on the state-of-the-art in this rapidly evolving field. These papers, many of which are based on notable presentations given during the Madrid conference, feature highlights such as (1) the development of sophisticated force spectroscopy procedures that are able to map the complete 3D tip-sample force field on different surfaces; (2) the considerable resolution improvement of Kelvin probe force microscopy (reaching, in some cases, the atomic scale), which is accompanied by a thorough, quantitative understanding of the contrast observed; (3) the perfecting of atomic resolution imaging on insulating substrates, which helps reshape our microscopic understanding of surface properties and chemical activity of these surfaces; (4) the description of instrumental and methodological developments that pave the way to the atomic-scale characterization of magnetic and electronic properties of nanostructures, and last but not least (5) the extension of dynamic imaging modes to high-resolution operation in liquids, ultimately achieving atomic resolution. The latter developments are already having a significant impact in the highly competitive field of biological imaging under physiological conditions. This special issue of Nanotechnology would not have been possible without the highly professional support from Nina Couzin, Amy Harvey, Alex Wotherspoon and the entire Nanotechnology team at IOP Publishing. We are thankful for their help in pushing this project forward. We also thank the authors who have contributed their excellent original articles to this issue, the referees whose comments have helped make the issue an accurate portrait of this rapidly moving field, and the entire NC-AFM community that continues to drive NC-AFM to new horizons.

  8. Understanding reconstructed Dante spectra using high resolution spectroscopy

    Science.gov (United States)

    May, M. J.; Weaver, J.; Widmann, K.; Kemp, G. E.; Thorn, D.; Colvin, J. D.; Schneider, M. B.; Moore, A.; Blue, B. E.

    2016-11-01

    The Dante is an 18 channel filtered diode array used at the National Ignition Facility (NIF) to measure the spectrally and temporally resolved radiation flux between 50 eV and 20 keV from various targets. The absolute flux is determined from the radiometric calibration of the x-ray diodes, filters, and mirrors and a reconstruction algorithm applied to the recorded voltages from each channel. The reconstructed spectra are very low resolution with features consistent with the instrument response and are not necessarily consistent with the spectral emission features from the plasma. Errors may exist between the reconstructed spectra and the actual emission features due to assumptions in the algorithm. Recently, a high resolution convex crystal spectrometer, VIRGIL, has been installed at NIF with the same line of sight as the Dante. Spectra from L-shell Ag and Xe have been recorded by both VIRGIL and Dante. Comparisons of these two spectroscopic measurements yield insights into the accuracy of the Dante reconstructions.

  9. Understanding reconstructed Dante spectra using high resolution spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    May, M. J., E-mail: may13@llnl.gov; Widmann, K.; Kemp, G. E.; Thorn, D.; Colvin, J. D.; Schneider, M. B.; Moore, A.; Blue, B. E. [L-170 Lawrence Livermore National Laboratory, 7000 East Ave., Livermore, California 94551 (United States); Weaver, J. [Naval Research Laboratory, 4555 Overlook Ave. SW, Washington, DC 20375 (United States)

    2016-11-15

    The Dante is an 18 channel filtered diode array used at the National Ignition Facility (NIF) to measure the spectrally and temporally resolved radiation flux between 50 eV and 20 keV from various targets. The absolute flux is determined from the radiometric calibration of the x-ray diodes, filters, and mirrors and a reconstruction algorithm applied to the recorded voltages from each channel. The reconstructed spectra are very low resolution with features consistent with the instrument response and are not necessarily consistent with the spectral emission features from the plasma. Errors may exist between the reconstructed spectra and the actual emission features due to assumptions in the algorithm. Recently, a high resolution convex crystal spectrometer, VIRGIL, has been installed at NIF with the same line of sight as the Dante. Spectra from L-shell Ag and Xe have been recorded by both VIRGIL and Dante. Comparisons of these two spectroscopic measurements yield insights into the accuracy of the Dante reconstructions.

  10. High Resolution Studies of Mass Loss from Massive Binary Stars

    Science.gov (United States)

    Corcoran, Michael F.; Gull, Theodore R.; Hamaguchi, Kenji; Richardson, Noel; Madura, Thomas; Post Russell, Christopher Michael; Teodoro, Mairan; Nichols, Joy S.; Moffat, Anthony F. J.; Shenar, Tomer; Pablo, Herbert

    2017-01-01

    Mass loss from hot luminous single and binary stars has a significant, perhaps decisive, effect on their evolution. The combination of X-ray observations of hot shocked gas embedded in the stellar winds and high-resolution optical/UV spectra of the cooler mass in the outflow provides unique ways to study the unstable process by which massive stars lose mass both through continuous stellar winds and rare, impulsive, large-scale mass ejections. The ability to obtain coordinated observations with the Hubble Space Telescope Imaging Spectrograph (HST/STIS) and the Chandra High-Energy Transmission Grating Spectrometer (HETGS) and other X-ray observatories has allowed, for the first time, studies of resolved line emisssion over the temperature range of 104- 108K, and has provided observations to confront numerical dynamical models in three dimensions. Such observations advance our knowledge of mass-loss asymmetries, spatial and temporal variabilities, and the fundamental underlying physics of the hot shocked outflow, providing more realistic constraints on the amount of mass lost by different luminous stars in a variety of evolutionary stages. We discuss the impact that these joint observational studies have had on our understanding of dynamical mass outflows from massive stars, with particular emphasis on two important massive binaries, Delta Ori Aa, a linchpin of the mass luminosity relation for upper HRD main sequence stars, and the supermassive colliding wind binary Eta Carinae.

  11. High resolution Doppler imager on the Upper Atmosphere Research Satellite

    Energy Technology Data Exchange (ETDEWEB)

    Skinner, W.R.; Hays, P.B.; Grassl, H.J.; Gell, D.A.; Burrage, M.D.; Marshall, A.R.; Ortland, D.A. [Univ. of Michigan, Ann Arbor, MI (United States)

    1994-12-31

    The High Resolution Doppler Imager (HRDI) on the Upper Atmosphere Research Satellite has been providing measurements of the wind field in the stratosphere, mesosphere and lower thermosphere since November 1991. Examination of various calibration data indicates the instrument has remained remarkably stable since launch. The instrument has a thermal drift of about 30 m/s/{degree}C (slightly dependent on wavelength) and a long-term temporal drift that has amounted to about 80 m/s since launch. These effects are removed in the data processing leaving an uncertainty in the instrument stability of {minus}2 nVs. The temperature control of the instrument has improved significantly since launch as a new method was implemented. The initial temperature control held the instrument temperature at about {+-}1{degree}C. The improved method, which holds constant the temperature of the optical bench instead of the radiator, keeps the instrument temperature at about 0.2{degree}C. The calibrations indicate very little change in the sensitivity of the instrument. The detector response has shown no degradation and the optics have not changed their transmittance.

  12. Evaluation of Round Window Stimulation Using the Floating Mass Transducer by Intracochlear Sound Pressure Measurements in Human Temporal Bones

    Science.gov (United States)

    Nakajima, Hideko Heidi; Dong, Wei; Olson, Elizabeth S.; Rosowski, John J.; Ravicz, Michael E.; Merchant, Saumil N.

    2009-01-01

    Hypothesis Round window (RW) stimulation with a floating mass transducer (FMT) can be studied experimentally and optimized to enhance auditory transduction. Background The FMT (MED-EL Vibrant Soundbridge) has been recently implanted in patients with refractory conductive or mixed hearing loss to stimulate the RW with varying degrees of success. The mechanics of RW stimulation with the FMT have not been studied in a systematic manner. Methods In cadaveric human temporal bones, measurements of stapes velocity with laser vibrometry in response to FMT-RW stimulation were used to optimize FMT insertion. The effect of RW stimulation on hearing was estimated using simultaneous measurements of intracochlear pressures in both perilymphatic scalae with micro-optical pressure transducers. This enabled calculation of the differential pressure across the cochlear partition, which is directly tied to auditory transduction. Results The best coupling between the FMT and RW was achieved with a piece of fascia placed between the RW and the FMT, and by "bracing" the free end of the FMT against the hypotympanic wall with dental impression material. FMT-RW stimulation provided differential pressures comparable to sound-induced oval window stimulation above 1 kHz. However, below 1 kHz the FMT was less capable. Conclusions Measurements of stapes velocity and intracochlear sound pressures in scala vestibuli and scala tympani enabled experimental evaluation of FMT stimulation of the RW. The efficacy of FMT-RW coupling was influenced significantly by technical and surgical factors, which can be optimized. This temporal bone preparation also lays the foundation for future studies to investigate multiple issues of relevance to both basic and clinical science such as RW stimulation in stapes fixation, non-aerated middle-ears and third-window lesions, and to answer basic questions regarding bone conduction. PMID:19841600

  13. Using high-resolution displays for high-resolution cardiac data.

    Science.gov (United States)

    Goodyer, Christopher; Hodrien, John; Wood, Jason; Kohl, Peter; Brodlie, Ken

    2009-07-13

    The ability to perform fast, accurate, high-resolution visualization is fundamental to improving our understanding of anatomical data. As the volumes of data increase from improvements in scanning technology, the methods applied to visualization must evolve. In this paper, we address the interactive display of data from high-resolution magnetic resonance imaging scanning of a rabbit heart and subsequent histological imaging. We describe a visualization environment involving a tiled liquid crystal display panel display wall and associated software, which provides an interactive and intuitive user interface. The oView software is an OpenGL application that is written for the VR Juggler environment. This environment abstracts displays and devices away from the application itself, aiding portability between different systems, from desktop PCs to multi-tiled display walls. Portability between display walls has been demonstrated through its use on walls at the universities of both Leeds and Oxford. We discuss important factors to be considered for interactive two-dimensional display of large three-dimensional datasets, including the use of intuitive input devices and level of detail aspects.

  14. Accelerated high-resolution photoacoustic tomography via compressed sensing

    Science.gov (United States)

    Arridge, Simon; Beard, Paul; Betcke, Marta; Cox, Ben; Huynh, Nam; Lucka, Felix; Ogunlade, Olumide; Zhang, Edward

    2016-12-01

    Current 3D photoacoustic tomography (PAT) systems offer either high image quality or high frame rates but are not able to deliver high spatial and temporal resolution simultaneously, which limits their ability to image dynamic processes in living tissue (4D PAT). A particular example is the planar Fabry-Pérot (FP) photoacoustic scanner, which yields high-resolution 3D images but takes several minutes to sequentially map the incident photoacoustic field on the 2D sensor plane, point-by-point. However, as the spatio-temporal complexity of many absorbing tissue structures is rather low, the data recorded in such a conventional, regularly sampled fashion is often highly redundant. We demonstrate that combining model-based, variational image reconstruction methods using spatial sparsity constraints with the development of novel PAT acquisition systems capable of sub-sampling the acoustic wave field can dramatically increase the acquisition speed while maintaining a good spatial resolution: first, we describe and model two general spatial sub-sampling schemes. Then, we discuss how to implement them using the FP interferometer and demonstrate the potential of these novel compressed sensing PAT devices through simulated data from a realistic numerical phantom and through measured data from a dynamic experimental phantom as well as from in vivo experiments. Our results show that images with good spatial resolution and contrast can be obtained from highly sub-sampled PAT data if variational image reconstruction techniques that describe the tissues structures with suitable sparsity-constraints are used. In particular, we examine the use of total variation (TV) regularization enhanced by Bregman iterations. These novel reconstruction strategies offer new opportunities to dramatically increase the acquisition speed of photoacoustic scanners that employ point-by-point sequential scanning as well as reducing the channel count of parallelized schemes that use detector arrays.

  15. Bone

    Science.gov (United States)

    Helmberger, Thomas K.; Hoffmann, Ralf-Thorsten

    The typical clinical signs in bone tumours are pain, destruction and destabilization, immobilization, neurologic deficits, and finally functional impairment. Primary malignant bone tumours are a rare entity, accounting for about 0.2% of all malignancies. Also benign primary bone tumours are in total rare and mostly asymptomatic. The most common symptomatic benign bone tumour is osteoid osteoma with an incidence of 1:2000.

  16. Methods to assess high-resolution subsurface gas concentrations and gas fluxes in wetland ecosystems

    DEFF Research Database (Denmark)

    Elberling, Bo; Kühl, Michael; Glud, Ronnie N.

    2013-01-01

    The need for measurements of soil gas concentrations and surface fluxes of greenhouse gases at high temporal and spatial resolution in wetland ecosystem has lead to the introduction of several new analytical techniques and methods. In addition to the automated flux chamber methodology for high......-resolution estimates of greenhouse gas fluxes across the soil-atmosphere interface, these high-resolution methods include microsensors for quantification of spatiotemporal concentration dynamics in O2 and N2O at micrometer scales, fiber-optic optodes for long-term continuous point measurements of O2 concentrations...... and peat soils are highly heterogeneous, containing a mosaic of dynamic macropore systems created by both macrofauna and flora leading to distinct spatial and temporal variations in gas concentration on a scale of millimeters and minutes. Applications of these new methodologies allow measurements...

  17. High-Resolution Force Balance Analyses of Tidewater Glacier Dynamics

    Science.gov (United States)

    Enderlin, E. M.; Hamilton, G. S.; O'Neel, S.

    2015-12-01

    Changes in glacier velocity, thickness, and terminus position have been used to infer the dynamic response of tidewater glaciers to environmental perturbations, yet few analyses have attempted to quantify the associated variations in the glacier force balance. Where repeat high-resolution ice thickness and velocity estimates are available, force balance time series can be constructed to investigate the redistribution of driving and resistive forces associated with changes in terminus position. Comparative force balance analyses may, therefore, help us understand the variable dynamic response observed for glaciers in close proximity to each other. Here we construct force balance time series for Helheim Glacier, SE Greenland, and Columbia Glacier, SE Alaska, to investigate differences in dynamic sensitivity to terminus position change. The analysis relies on in situ and remotely sensed observations of ice thickness, velocity, and terminus position. Ice thickness time series are obtained from stereo satellite image-derived surface elevation and continuity-derived bed elevations that are constrained by airborne radar observations. Surface velocity time series are obtained from interferometric synthetic aperture radar (InSAR) observations. Approximately daily terminus positions are from a combination of satellite images and terrestrial time-lapse photographs. Helheim and Columbia glaciers are two of the best-studied Arctic tidewater glaciers with comprehensive high-resolution observational time series, yet we find that bed elevation uncertainties and poorly-constrained stress-coupling length estimates still hinder the analysis of spatial and temporal force balance variations. Here we use a new observationally-based method to estimate the stress-coupling length which successfully reduces noise in the derived force balance but preserves spatial variations that can be over-smoothed when estimating the stress-coupling length as a scalar function of the ice thickness

  18. Sunspot Group Development in High Resolution

    CERN Document Server

    Muraközy, J; Ludmány, A

    2014-01-01

    The Solar and Heliospheric Obseratory/Michelson Doppler Imager--Debrecen Data (SDD) sunspot catalogue provides an opportunity to study the details and development of sunspot groups on a large statistical sample. The SDD data allow, in particular, the differential study of the leading and following parts with a temporal resolution of 1.5 hours. In this study, we analyse the equilibrium distance of sunspot groups as well as the evolution of this distance over the lifetime of the groups and the shifts in longitude associated with these groups. We also study the asymmetry between the compactness of the leading and following parts, as well as the time-profiles for the development of the area of sunspot groups. A logarithmic relationship has been found between the total area and the distance of leading-following parts of active regions (ARs) at the time of their maximum area. In the developing phase the leading part moves forward; this is more noticeable in larger ARs. The leading part has a higher growth rate than...

  19. 3D curved multiplanar cone beam CT reconstruction for intracochlear position assessment of straight electrodes array. A temporal bone and clinical study.

    Science.gov (United States)

    De Seta, D; Mancini, P; Russo, F Y; Torres, R; Mosnier, I; Bensimon, J L; De Seta, E; Heymann, D; Sterkers, O; Bernardeschi, D; Nguyen, Y

    2016-12-01

    A retrospective review of post-op cone beam CT (CBCT) of 8 adult patients and 14 fresh temporal bones that underwent cochlear implantation with straight flexible electrodes array was performed to determine if the position of a long and flexible electrodes array within the cochlear scalae could be reliably assessed with CBCT. An oto-radiologist and two otologists examined the images and assessed the electrodes position. The temporal bone specimens underwent histological analysis for confirm the exact position. The position of the electrodes was rated as scala tympani, scala vestibule, or intermediate position for the electrodes at 180°, 360° and for the apical electrode. In the patient group, for the electrodes at 180° all observers agreed for scala tympani position except for 1 evaluation, while a discrepancy in 3 patients both for the 360° and for the apical electrode assessment were found. In five temporal bones the evaluations were in discrepancy for the 180° electrode, while at 360° a disagreement between raters on the scalar positioning was seen in six temporal bones. A higher discrepancy between was found in assessment of the scalar position of the apical electrode (average pairwise agreement 45.4%, Fleiss k = 0.13). A good concordance was found between the histological results and the consensus between raters for the electrodes in the basal turn, while low agreement (Cohen's k 0.31, pairwise agreement 50%) was found in the identification of the apical electrode position confirming the difficulty to correct identify the electrode position in the second cochlear turn in temporal bones. In conclusion, CBCT is a reliable radiologic exam to correctly evaluate the position of a lateral wall flexible array in implanted patients using the proposed imaging reconstruction method, while some artefacts impede exact evaluation of the position of the apical electrode in temporal bone and other radiological techniques should be preferred in ex vivo studies.

  20. Achieving sensitive, high-resolution laser spectroscopy at CRIS

    Energy Technology Data Exchange (ETDEWEB)

    Groote, R. P. de [Instituut voor Kern- en Stralingsfysica, KU Leuven (Belgium); Lynch, K. M., E-mail: kara.marie.lynch@cern.ch [EP Department, CERN, ISOLDE (Switzerland); Wilkins, S. G. [The University of Manchester, School of Physics and Astronomy (United Kingdom); Collaboration: the CRIS collaboration

    2017-11-15

    The Collinear Resonance Ionization Spectroscopy (CRIS) experiment, located at the ISOLDE facility, has recently performed high-resolution laser spectroscopy, with linewidths down to 20 MHz. In this article, we present the modifications to the beam line and the newly-installed laser systems that have made sensitive, high-resolution measurements possible. Highlights of recent experimental campaigns are presented.

  1. High-resolution X-ray diffraction studies of multilayers

    DEFF Research Database (Denmark)

    Christensen, Finn Erland; Hornstrup, Allan; Schnopper, H. W.

    1988-01-01

    High-resolution X-ray diffraction studies of the perfection of state-of-the-art multilayers are presented. Data were obtained using a triple-axis perfect-crystal X-ray diffractometer. Measurements reveal large-scale figure errors in the substrate. A high-resolution triple-axis set up is required...

  2. Improving depiction of temporal bone anatomy with low-radiation dose CT by an integrated circuit detector in pediatric patients: a preliminary study.

    Science.gov (United States)

    He, Jingzhen; Zu, Yuliang; Wang, Qing; Ma, Xiangxing

    2014-12-01

    The purpose of this study was to determine the performance of low-dose computed tomography (CT) scanning with integrated circuit (IC) detector in defining fine structures of temporal bone in children by comparing with the conventional detector. The study was performed with the approval of our institutional review board and the patients' anonymity was maintained. A total of 86 children0.05). The low-dose CT images acquired with the IC detector provide better depiction of fine osseous structures of temporal bone than that with the conventional DC detector.

  3. High-resolution CT with histopathological correlates of the classic metaphyseal lesion of infant abuse

    Energy Technology Data Exchange (ETDEWEB)

    Tsai, Andy; Kleinman, Paul K. [Boston Children' s Hospital, Department of Radiology, Boston, MA (United States); McDonald, Anna G. [Office of the Chief Medical Examiner, Boston, MA (United States); Rosenberg, Andrew E. [University of Miami Hospital, Department of Pathology, Miami, FL (United States); Gupta, Rajiv [Massachusetts General Hospital, Department of Radiology, Boston, MA (United States)

    2014-02-15

    The classic metaphyseal lesion (CML) is a common high specificity indicator of infant abuse and its imaging features have been correlated histopathologically in infant fatalities. High-resolution CT imaging and histologic correlates were employed to (1) characterize the normal infant anatomy surrounding the chondro-osseous junction, and (2) confirm the 3-D model of the CML previously inferred from planar radiography and histopathology. Long bone specimens from 5 fatally abused infants, whose skeletal survey showed definite or suspected CMLs, were studied postmortem. After skeletal survey, selected specimens were resected and imaged with high-resolution digital radiography. They were then scanned with micro-CT (isotropic resolution of 45 μm{sup 3}) or with high-resolution flat-panel CT (isotropic resolutions of 200 μm{sup 3}). Visualization of the bony structures was carried out using image enhancement, segmentation and isosurface extraction, together with volume rendering and multiplanar reformatting. These findings were then correlated with histopathology. Study of normal infant bone clarifies the 3-D morphology of the subperiosteal bone collar (SPBC) and the radiographic zone of provisional calcification (ZPC). Studies on specimens with CML confirm that this lesion is a fracture extending in a planar fashion through the metaphysis, separating a mineralized fragment. This disk-like mineralized fragment has two components: (1) a thick peripheral component encompassing the SPBC; and (2) a thin central component comprised predominantly of the radiologic ZPC. By manipulating the 3-D model, the varying appearances of the CML are displayed. High-resolution CT coupled with histopathology provides elucidation of the morphology of the CML, a strong indicator of infant abuse. This new information may prove useful in assessing the biomechanical factors that produce this strong indicator of abusive assaults in infants. (orig.)

  4. Ultra-high resolution electron microscopy

    Science.gov (United States)

    Oxley, Mark P.; Lupini, Andrew R.; Pennycook, Stephen J.

    2017-02-01

    The last two decades have seen dramatic advances in the resolution of the electron microscope brought about by the successful correction of lens aberrations that previously limited resolution for most of its history. We briefly review these advances, the achievement of sub-Ångstrom resolution and the ability to identify individual atoms, their bonding configurations and even their dynamics and diffusion pathways. We then present a review of the basic physics of electron scattering, lens aberrations and their correction, and an approximate imaging theory for thin crystals which provides physical insight into the various different imaging modes. Then we proceed to describe a more exact imaging theory starting from Yoshioka’s formulation and covering full image simulation methods using Bloch waves, the multislice formulation and the frozen phonon/quantum excitation of phonons models. Delocalization of inelastic scattering has become an important limiting factor at atomic resolution. We therefore discuss this issue extensively, showing how the full-width-half-maximum is the appropriate measure for predicting image contrast, but the diameter containing 50% of the excitation is an important measure of the range of the interaction. These two measures can differ by a factor of 5, are not a simple function of binding energy, and full image simulations are required to match to experiment. The Z-dependence of annular dark field images is also discussed extensively, both for single atoms and for crystals, and we show that temporal incoherence must be included accurately if atomic species are to be identified through matching experimental intensities to simulations. Finally we mention a few promising directions for future investigation.

  5. [Malformations and abnormalities of the petrous portion of the temporal bone].

    Science.gov (United States)

    Reith, W; Yilmaz, U; Heumüller, I

    2014-04-01

    High-resolution computed tomography (HRCT) is the procedure of choice in the diagnostics of abnormalities of the middle and inner ear. It allows a detailed presentation of anatomical features and achieves the prerequisites for selection of the various therapeutic options. The highly diverse abnormalities can be described using detailed imaging analyses. Malformations with an abnormally developed modiolus are assumed to be early embryological defects, such as the classical Mondini dysplasia. The essential therapeutic option for middle ear deformities is still a cochlear implant. The domain of magnetic resonance imaging (MRI) is not only in the analysis of the cochlear nerve and for exclusion of fibrosis or ossification of the labyrinth but is also able to visualize details of isolated malformations, such as an extended vestibular aqueduct or subtle alterations to the vestibule or can visualize them better in comparison to CT. Radiological diagnostics are used not only for classification but also to recognize typical clinical problem situations and play a key role in the diagnostics of hearing disorders and selection of the optimal therapeutic procedure.

  6. High resolution multi-scalar drought indices for Iberia

    Science.gov (United States)

    Russo, Ana; Gouveia, Célia; Trigo, Ricardo; Jerez, Sonia

    2014-05-01

    The Iberian Peninsula has been recurrently affected by drought episodes and by adverse associated effects (Gouveia et al., 2009), ranging from severe water shortages to losses of hydroelectricity production, increasing risk of forest fires, forest decline and triggering processes of land degradation and desertification. Moreover, Iberia corresponds to one of the most sensitive areas to current and future climate change and is nowadays considered a hot spot of climate change with high probability for the increase of extreme events (Giorgi and Lionello, 2008). The spatial and temporal behavior of climatic droughts at different time scales was analyzed using spatially distributed time series of multi-scalar drought indicators, such as the Standardized Precipitation Evapotranspiration Index (SPEI) (Vicente-Serrano et al., 2010). This new climatic drought index is based on the simultaneous use of precipitation and temperature fields with the advantage of combining a multi-scalar character with the capacity to include the effects of temperature variability on drought assessment. Moreover, reanalysis data and the higher resolution hindcasted databases obtained from them are valuable surrogates of the sparse observations and widely used for in-depth characterizations of the present-day climate. Accordingly, this work aims to enhance the knowledge on high resolution drought patterns in Iberian Peninsula, taking advantage of high-resolution (10km) regional MM5 simulations of the recent past (1959-2007) over Iberia. It should be stressed that these high resolution meteorological fields (e.g. temperature, precipitation) have been validated for various purposes (Jerez et al., 2013). A detailed characterization of droughts since the 1960s using the 10 km resolution hidncasted simulation was performed with the aim to explore the conditions favoring drought onset, duration and ending, as well as the subsequent short, medium and long-term impacts affecting the environment and the

  7. Significance of temporal bone CT scan for exposure of the facial canal and the lateral semicircular canal in cholesteatoma

    Energy Technology Data Exchange (ETDEWEB)

    Sung, Ki Joon; Kim, Dong Jin; Kim, Myung Soon; Kim, Young Ju; Kweon, Joon [Wonju College of Medicine, Yonsei University, Wonju (Korea, Republic of)

    1991-09-15

    By reviewing retrospectively the HRCT findings in 130 surgically proven cases of chronic otitis media with cholesteatoma, we estimated the sensitivity, specificity, and positive predictability of the HRCT compared to surgical findings. For exposure of the facial canal, the sensitivity, specificity, and positive predictability was 59.7%, 84.9%, and 85.2% respectively. For exposure of the lateral semicircular canal, the sensitivity was 80.6%, the specificity 99.0%, and the positive predictability 96.2%. Conclusively, the diagnostic accuracy of preoperative temporal bone CT regarding the state of the lateral semicircular canal seems to be highly reliable. Gross invasion of the facial canal can be usually detected. However, relatively low sensitivity suggests that evaluation of the ultra-thin structures of the tympanic segment is often problematic.

  8. Malformations and abnormalities of the petrous portion of the temporal bone; Fehlbildungen und Missbildungen des Felsenbeins

    Energy Technology Data Exchange (ETDEWEB)

    Reith, W.; Yilmaz, U. [Universitaetsklinikum des Saarlandes, Klinik fuer Diagnostische und Interventionelle Neuroradiologie, Homburg/Saar (Germany); Heumueller, I. [Westpfalzklinikum Kaiserslautern, Institut fuer Radiologie, Kaiserslautern (Germany)

    2014-04-15

    High-resolution computed tomography (HRCT) is the procedure of choice in the diagnostics of abnormalities of the middle and inner ear. It allows a detailed presentation of anatomical features and achieves the prerequisites for selection of the various therapeutic options. The highly diverse abnormalities can be described using detailed imaging analyses. Malformations with an abnormally developed modiolus are assumed to be early embryological defects, such as the classical Mondini dysplasia. The essential therapeutic option for middle ear deformities is still a cochlear implant. The domain of magnetic resonance imaging (MRI) is not only in the analysis of the cochlear nerve and for exclusion of fibrosis or ossification of the labyrinth but is also able to visualize details of isolated malformations, such as an extended vestibular aqueduct or subtle alterations to the vestibule or can visualize them better in comparison to CT. Radiological diagnostics are used not only for classification but also to recognize typical clinical problem situations and play a key role in the diagnostics of hearing disorders and selection of the optimal therapeutic procedure. (orig.) [German] Die hochaufloesende CT ist das Verfahren der Wahl in der Diagnostik von Fehlbildungen des Mittel- und Innenohrs. Sie erlaubt die detaillierte Darstellung anatomischer Details und schafft die Voraussetzung fuer die unterschiedlichen Therapieoptionen. Durch detaillierte bildgebenden Analysen koennen die unterschiedlichsten Fehlbildungen beschrieben werden. Fehlbildungen mit einem nicht normal ausgebildeten Modiolus werden als fruehere embryologische Schaedigungen als die klassische Mondini-Dysplasie angesehen. Die wesentliche therapeutische Option bei Mittelohrfehlbildung bleibt das Kochleaimplantat. Die Domaene der MRT liegt nicht nur in der Analyse des N. cochlearis und im Ausschluss von Fibrosierungen oder Ossifikationen des Labyrinths, sondern darueber hinaus ist sie in der Lage, Details einzelner

  9. The usefulness of MR imaging of the temporal bone in the evaluation of patients with facial and audiovestibular dysfunction

    Energy Technology Data Exchange (ETDEWEB)

    Park, Sang Uk; Kim, Hyung Jin; Cho, Young Kuk; Lim, Myung Kwan; Kim, Won Hong; Suh, Chang Hae; Lee, Seung Chul [Inha University College of Medicine, Incheon (Korea, Republic of)

    2002-01-01

    To evaluate the clinical utility of MR imaging of the temporal bone in patients with facial and audiovestibular dysfunction with particular emphasis on the importance of contrast enhancement. We retrospectively reviewed the MR images of 179 patients [72 men, 107 women; average age, 44 (range, 1-77) years] who presented with peripheral facial palsy (n=15), audiometrically proven sensorineural hearing loss (n=104), vertigo (n=109), or tinnitus (n=92). Positive MR imaging findings possibly responsible for the patients' clinical manifestations were categorized according to the anatomic sites and presumed etiologies of the lesions. We also assessed the utility of contrast-enhanced MR imaging by analyzing its contribution to the demonstration of lesions which would otherwise not have been apparent. All MR images were interpreted by two neuroradiologists, who reached their conclusions by consensus. MR images demonstrated positive findings, thought to account for the presenting symptoms, in 78 (44%) of 179 patients, including 15 (100%) of 15 with peripheral facial palsy, 43 (41%) of 104 with sensorineural hearing loss, 40 (37%) of 109 with vertigo, and 39 (42%) of 92 with tinnitus. Thirty (38%) of those 78 patients had lesions that could be confidently recognized only at contrast-enhanced MR imaging. Even though its use led to positive findings in less than half of these patients, MR imaging of the temporal bone is a useful diagnostic procedure in the evaluation of those with facial and audiovestibular dysfunction. Because it was only at contrast-enhanced MR imaging that a significant number of patients showed positive imaging findings which explained their clinical manifestations, the use of contrast material is highly recommended.

  10. Anatomy-Specific Virtual Reality Simulation in Temporal Bone Dissection: Perceived Utility and Impact on Surgeon Confidence.

    Science.gov (United States)

    Locketz, Garrett D; Lui, Justin T; Chan, Sonny; Salisbury, Kenneth; Dort, Joseph C; Youngblood, Patricia; Blevins, Nikolas H

    2017-06-01

    Objective To evaluate the effect of anatomy-specific virtual reality (VR) surgical rehearsal on surgeon confidence and temporal bone dissection performance. Study Design Prospective pre- and poststudy of a novel virtual surgical rehearsal platform. Setting Academic otolaryngology-head and neck surgery residency training programs. Subjects and Methods Sixteen otolaryngology-head and neck surgery residents from 2 North American training institutions were recruited. Surveys were administered to assess subjects' baseline confidence in performing 12 subtasks of cortical mastoidectomy with facial recess. A cadaver temporal bone was randomly assigned to each subject. Cadaver specimens were scanned with a clinical computed tomography protocol, allowing the creation of anatomy-specific models for use in a VR surgical rehearsal platform. Subjects then rehearsed a virtual mastoidectomy on data sets derived from their specimens. Surgical confidence surveys were administered again. Subjects then dissected assigned cadaver specimens, which were blindly graded with a modified Welling scale. A final survey assessed the perceived utility of rehearsal on dissection performance. Results Of 16 subjects, 14 (87.5%) reported a significant increase in overall confidence after conducting an anatomy-specific VR rehearsal. A significant correlation existed between perceived utility of rehearsal and confidence improvement. The effect of rehearsal on confidence was dependent on trainee experience and the inherent difficulty of the surgical subtask. Postrehearsal confidence correlated strongly with graded dissection performance. Subjects rated anatomy-specific rehearsal as having a moderate to high contribution to their dissection performance. Conclusion Anatomy-specific virtual rehearsal improves surgeon confidence in performing mastoid dissection, dependent on surgeon experience and task difficulty. The subjective confidence gained through rehearsal correlates positively with subsequent

  11. The songbird syrinx morphome: a three-dimensional, high-resolution, interactive morphological map of the zebra finch vocal organ

    DEFF Research Database (Denmark)

    During, D. N.; Ziegler, A.; Thompson, C. K.;

    2013-01-01

    and micro-computed tomography) and invasive techniques (histology and micro-dissection) to construct the annotated high-resolution three-dimensional dataset, or morphome, of the zebra finch (Taeniopygia guttata) syrinx. We identified and annotated syringeal cartilage, bone and musculature in situ...

  12. A novel framework for the temporal analysis of bone mineral density in metastatic lesions using CT images of the femur

    Science.gov (United States)

    Knoop, Tom H.; Derikx, Loes C.; Verdonschot, Nico; Slump, Cornelis H.

    2015-03-01

    In the progressive stages of cancer, metastatic lesions in often develop in the femur. The accompanying pain and risk of fracture dramatically affect the quality of life of the patient. Radiotherapy is often administered as palliative treatment to relieve pain and restore the bone around the lesion. It is thought to affect the bone mineralization of the treated region, but the quantitative relation between radiation dose and femur remineralization remains unclear. A new framework for the longitudinal analysis of CT-scans of patients receiving radiotherapy is presented to investigate this relationship. The implemented framework is capable of automatic calibration of Hounsfield Units to calcium equivalent values and the estimation of a prediction interval per scan. Other features of the framework are temporal registration of femurs using elastix, transformation of arbitrary Regions Of Interests (ROI), and extraction of metrics for analysis. Build in Matlab, the modular approach aids easy adaptation to the pertinent questions in the explorative phase of the research. For validation purposes, an in-vitro model consisting of a human cadaver femur with a milled hole in the intertrochanteric region was used, representing a femur with a metastatic lesion. The hole was incrementally stacked with plates of PMMA bone cement with variable radiopaqueness. Using a Kolmogorov-Smirnov (KS) test, changes in density distribution due to an increase of the calcium concentration could be discriminated. In a 21 cm3 ROI, changes in 8% of the volume from 888 ± 57mg • ml-1 to 1000 ± 80mg • ml-1 could be statistically proven using the proposed framework. In conclusion, the newly developed framework proved to be a useful and flexible tool for the analysis of longitudinal CT data.

  13. High Resolution Projection of Future Air Quality in South Asia

    Science.gov (United States)

    Kumar, R.; Barth, M. C.; Pfister, G.; Lamarque, J. F.; Walters, S.; Naja, M. K.; Ghude, S. D.

    2015-12-01

    About one seventh of the world's population living in South Asia faces the risk of severe air pollution due to high anthropogenic emissions of air pollutants. Recent studies have shown that exposure to present day air pollution in South Asia is sufficient enough to reduce the lifespan of about 660 million people by about 3 years, destroy food that can feed about 94 million poor people and cause economic loss of several billion dollars. This problem may worsen in the future as anthropogenic emissions are expected to increase due to rapid economic growth in South Asia, and climate change is expected to lead to atmospheric conditions conducive for the production and accumulation of air pollutants. In order to predict how air quality will change in South Asia in future (2050), we are conducting high resolution air quality simulations for the present day (2005-2014) and future (2046-2055) time periods using the Nested Regional Climate Model coupled with Chemistry (NRCM-Chem). The model domain covers entire South Asia at a horizontal grid spacing of 60 km with a nested domain over the densely populated and polluted Indo-Gangetic Plain region at a horizontal grid spacing of 12 km. The model results are being evaluated with available in situ and satellite based observations and the evaluation results show that NRCM-Chem model is able to capture several important features of the observed spatial and temporal distribution of key meteorological parameters and air pollutants. Initial model results show that annual average surface ozone and PM2.5 concentrations may increase by up to 15 ppbv and 25 μg m-3, respectively with highest increase in the Indo-Gangetic Plain.

  14. Nontumorous enlargement of the internal auditory canal. A risk factor for sensorineural hearing loss? A high resolution CT-study

    Energy Technology Data Exchange (ETDEWEB)

    Stimmer, H.; Rummeny, E.J. [Technical University Munich, Klinikum rechts der Isar (Germany). Dept. of Radiology; Niedermeyer, H.P. [Technical University Munich, Klinikum rechts der Isar (Germany). ENT-Clinic; Kehl, V. [Technical University Munich, Klinikum rechts der Isar (Germany). Inst. for Medical Statistics and Epidemiology

    2015-06-15

    First aim of the study was to define normal shape and diameter of the internal auditory canal (IAC). In the second part the clinical relevance of IAC-enlargement was analyzed, considering also lesions of the subtle structures at the fundus of the internal auditory canal. 440 high resolution CT-scans of the temporal bone were used for retrospective analysis of the internal auditory canal and its fundus region. The mean value of the IAC diameter in axial and coronal plane was determined. In 20 of 440 patients IAC enlargement was found. In the group with pronounced enlargement (3fold SD) nearly all patients suffered from hearing impairment. In some of them we found structural abnormalities near the IAC fundus in the CSF/perilymph border zone. A new CT-based definition of normal shape and diameter of the internal auditory canal is presented. There is some evidence that a pathologic transmission of CSF-pressure in case of IAC-enlargement and/or abnormal fistulous communications could play an important role in the pathophysiology of hearing loss.

  15. High-Resolution Finite Volume Modeling of Wave Propagation in Orthotropic Poroelastic Media

    CERN Document Server

    Lemoine, Grady I; LeVeque, Randall J

    2012-01-01

    Poroelasticity theory models the dynamics of porous, fluid-saturated media. It was pioneered by Maurice Biot in the 1930s through 1960s, and has applications in several fields, including geophysics and modeling of in vivo bone. A wide variety of methods have been used to model poroelasticity, including finite difference, finite element, pseudospectral, and discontinuous Galerkin methods. In this work we use a Cartesian-grid high-resolution finite volume method to numerically solve Biot's equations in the time domain for orthotropic materials, with the stiff relaxation source term in the equations incorporated using operator splitting. This class of finite volume method has several useful properties, including the ability to use wave limiters to reduce numerical artifacts in the solution, ease of incorporating material inhomogeneities, low memory overhead, and an explicit time-stepping approach. To the authors' knowledge, this is the first use of high-resolution finite volume methods to model poroelasticity. T...

  16. High Resolution CryoFESEM of Microbial Surfaces

    Science.gov (United States)

    Erlandsen, Stanley; Lei, Ming; Martin-Lacave, Ines; Dunny, Gary; Wells, Carol

    2003-08-01

    The outer surfaces of three microorganisms, Giardia lamblia, Enterococcus faecalis, and Proteus mirabilis, were investigated by cryo-immobilization followed by sublimation of extracellular ice and cryocoating with either Pt alone or Pt plus carbon. Cryocoated samples were examined at [minus sign]125°C in either an in-lens field emission SEM or a below-the-lens field emission SEM. Cryocoating with Pt alone was sufficient for low magnification observation, but attempts to do high-resolution imaging resulted in radiolysis and cracking of the specimen surface. Double coating with Pt and carbon, in combination with high resolution backscatter electron detectors, enabled high-resolution imaging of the glycocalyx of bacteria, revealing a sponge-like network over the surface. High resolution examination of bacterial flagella also revealed a periodic substructure. Common artifacts included radiolysis leading to “cracking” of the surface, and insufficient deposition of Pt resulting in the absence of detectable surface topography.

  17. High resolution emission tomography; Tomographie d`emission haute resolution

    Energy Technology Data Exchange (ETDEWEB)

    Charon, Y.; Laniece, P.; Mastrippolito, R.; Pinot, L.; Ploux, L.; Valda Ochoa, A.; Valentin, L. [Groupe I.P.B., Experimental Research Division, Inst. de Physique Nucleaire, Paris-11 Univ., 91 - Orsay (France)

    1999-11-01

    We have developed an original high resolution tomograph for in-vivo small animal imaging. A first prototype is under evaluation. Initial results of its characterisation are presented. (authors) 3 figs.

  18. High Resolution Orthoimagery = Orthorectified Metro Areas: 2000 - Present

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — High resolution orthorectified images combine the image characteristics of an aerial photograph with the geometric qualities of a map. An orthoimage is a...

  19. Methodology of high-resolution photography for mural condition database

    Science.gov (United States)

    Higuchi, R.; Suzuki, T.; Shibata, M.; Taniguchi, Y.

    2015-08-01

    Digital documentation is one of the most useful techniques to record the condition of cultural heritage. Recently, high-resolution images become increasingly useful because it is possible to show general views of mural paintings and also detailed mural conditions in a single image. As mural paintings are damaged by environmental stresses, it is necessary to record the details of painting condition on high-resolution base maps. Unfortunately, the cost of high-resolution photography and the difficulty of operating its instruments and software have commonly been an impediment for researchers and conservators. However, the recent development of graphic software makes its operation simpler and less expensive. In this paper, we suggest a new approach to make digital heritage inventories without special instruments, based on our recent our research project in Üzümlü church in Cappadocia, Turkey. This method enables us to achieve a high-resolution image database with low costs, short time, and limited human resources.

  20. High Resolution Screening of biologically active compounds and metabolites

    NARCIS (Netherlands)

    Kool, J.

    2007-01-01

    High Resolution Screening of biologically active compounds and metabolites Jeroen Kool Biotransformation enzymes play a crucial role in the metabolism of both endogenous compounds and xenobiotics. Usually, the detoxication of these compounds by biotransformation enzymes results in harmless metab

  1. NOAA High-Resolution Sea Surface Temperature (SST) Analysis Products

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This archive covers two high resolution sea surface temperature (SST) analysis products developed using an optimum interpolation (OI) technique. The analyses have a...

  2. High Resolution, Range/Range-Rate Imager Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Visidyne proposes to develop a design for a small, lightweight, high resolution, in x, y, and z Doppler imager to assist in the guidance, navigation and control...

  3. High-resolution spectroscopy of gases for industrial applications

    DEFF Research Database (Denmark)

    Fateev, Alexander; Clausen, Sønnik

    High-resolution spectroscopy of gases is a powerful technique which has various fundamental and practical applications: in situ simultaneous measurements of gas temperature and gas composition, radiative transfer modeling, validation of existing and developing of new databases and etc. Existing...... to, for example, atmospheric research, combustion and gasification. Some high-temperature, high-resolution IR/UV absorption/transmission measurements gases (e.g. CO2, SO2, SO3 and phenol) are presented....

  4. Developing Visual Editors for High-Resolution Haptic Patterns

    DEFF Research Database (Denmark)

    Cuartielles, David; Göransson, Andreas; Olsson, Tony

    2012-01-01

    In this article we give an overview of our iterative work in developing visual editors for creating high resolution haptic patterns to be used in wearable, haptic feedback devices. During the past four years we have found the need to address the question of how to represent, construct and edit high...... resolution haptic patterns so that they translate naturally to the user’s haptic experience. To solve this question we have developed and tested several visual editors...

  5. Geometric calibration of high-resolution remote sensing sensors

    Institute of Scientific and Technical Information of China (English)

    LIANG Hong-you; GU Xing-fa; TAO Yu; QIAO Chao-fei

    2007-01-01

    This paper introduces the applications of high-resolution remote sensing imagery and the necessity of geometric calibration for remote sensing sensors considering assurance of the geometric accuracy of remote sensing imagery. Then the paper analyzes the general methodology of geometric calibration. Taking the DMC sensor geometric calibration as an example, the paper discusses the whole calibration procedure. Finally, it gave some concluding remarks on geometric calibration of high-resolution remote sensing sensors.

  6. Scalable Algorithms for Large High-Resolution Terrain Data

    DEFF Research Database (Denmark)

    Mølhave, Thomas; Agarwal, Pankaj K.; Arge, Lars Allan

    2010-01-01

    In this paper we demonstrate that the technology required to perform typical GIS computations on very large high-resolution terrain models has matured enough to be ready for use by practitioners. We also demonstrate the impact that high-resolution data has on common problems. To our knowledge, some...... of the computations we present have never before been carried out by standard desktop computers on data sets of comparable size....

  7. Osteogenesis for postoperative temporal bone defects using human ear adipose-derived stromal cells and tissue engineering: an animal model study.

    Science.gov (United States)

    Kim, Yeon Ju; Park, Seung Gu; Shin, Beomyong; Kim, Jangho; Kim, Seung Won; Choo, Oak-Sung; Yin, Xiang Yun; Min, Byoung Hyun; Choung, Yun-Hoon

    2017-09-05

    Mastoidectomy, the removal of infected mastoid bones, is a common surgical procedure for the treatment of chronic otitis media. Persistent and recurrent otorrhea and accumulation of keratin debris following open cavity mastoidectomy are still bothersome issues for both patients and otologists. In this study, we used human ear adipose-derived stromal cells (hEASCs) in combination with polycaprolactone (PCL) scaffolds and osteogenic differentiation medium (ODM) to regenerate temporal bone defects. The hEASCs showed stem cell phenotypes, and these characteristics were maintained up to passage 5. Mastoid bulla and cranial bone defects were induced in Sprague-Dawley rats using AgNO3 and burr hole drilling, respectively, and the rats were then divided into five groups: (1) control, (2) hEASCs, (3) hEASCs + ODM, (4) hEASCs + PCL scaffolds, and (5) hEASCs + PCL scaffolds + ODM. Osteogenesis was evaluated by micro-computed tomography and histology. Compared with the control group, the groups transplanted with hEASCs and PCL scaffolds had significantly higher bone formation along the periphery of the mastoid bulla area. Moreover, ODM synergistically enhanced bone formation in mastoid bulla defects. Our results suggest that combining hEASCs with PCL scaffolds represents a promising method for anatomical and functional reconstruction of postoperative temporal bone defects following mastoidectomy. This article is protected by copyright. All rights reserved. © 2017 Wiley Periodicals, Inc.

  8. Performance of high-resolution X-band radar for rainfall measurement in The Netherlands

    Directory of Open Access Journals (Sweden)

    C. Z. van de Beek

    2010-02-01

    Full Text Available This study presents an analysis of 195 rainfall events gathered with the X-band weather radar SOLIDAR and a tipping bucket rain gauge network near Delft, The Netherlands, between May 1993 and April 1994. The aim of this paper is to present a thorough analysis of a climatological dataset using a high spatial (120 m and temporal (16 s resolution X-band radar. This makes it a study of the potential for high-resolution rainfall measurements with non-polarimetric X-band radar over flat terrain. An appropriate radar reflectivity – rain rate relation is derived from measurements of raindrop size distributions and compared with radar – rain gauge data. The radar calibration is assessed using a long-term comparison of rain gauge measurements with corresponding radar reflectivities as well as by analyzing the evolution of the stability of ground clutter areas over time. Three different methods for ground clutter correction as well as the effectiveness of forward and backward attenuation correction algorithms have been studied. Five individual rainfall events are discussed in detail to illustrate the strengths and weaknesses of high-resolution X-band radar and the effectiveness of the presented correction methods. X-band radar is found to be able to measure the space-time variation of rainfall at high resolution, far greater than what can be achieved by rain gauge networks or a typical operational C-band weather radar. On the other hand, SOLIDAR can suffer from receiver saturation, wet radome attenuation as well as signal loss along the path. During very strong convective situations the signal can even be lost completely. In combination with several rain gauges for quality control, high resolution X-band radar is considered to be suitable for rainfall monitoring over relatively small (urban catchments. These results offer great prospects for the new high resolution polarimetric doppler X-band radar IDRA.

  9. Performance of high-resolution X-band radar for rainfall measurement in The Netherlands

    Directory of Open Access Journals (Sweden)

    C. Z. van de Beek

    2009-09-01

    Full Text Available This study presents an analysis of 195 rainfall events gathered with the X-band weather radar SOLIDAR and a tipping bucket rain gauge network near Delft, The Netherlands, between May 1993 and April 1994. The high spatial (120 m and temporal (16 s resolution of the radar combined with the extent of the database make this study a climatological analysis of the potential for high-resolution rainfall measurement with non-polarimetric X-band radar over completely flat terrain. An appropriate radar reflectivity – rain rate relation is derived from measurements of raindrop size distributions and compared with radar – rain gauge data. The radar calibration is assessed using a long-term comparison of rain gauge measurements with corresponding radar reflectivities as well as by analyzing the evolution of the stability of ground clutter areas over time. Three different methods for ground clutter correction as well as the effectiveness of forward and backward attenuation correction algorithms have been studied. Five individual rainfall events are discussed in detail to illustrate the strengths and weaknesses of high-resolution X-band radar and the effectiveness of the presented correction methods. X-band radar is found to be able to measure the space-time variation of rainfall at high resolution, far greater than can be achieved by rain gauge networks or a typical operational C-band weather radar. On the other hand, SOLIDAR can suffer from receiver saturation, wet radome attenuation as well as signal loss along the path. During very strong convective situations the signal can even be lost completely. In combination with several rain gauges for quality control, high resolution X-band radar is considered to be suitable for rainfall monitoring over relatively small (urban catchments. These results offer great prospects for the new high resolution polarimetric doppler X-band radar IDRA.

  10. Data Driven Approach for High Resolution Population Distribution and Dynamics Models

    Energy Technology Data Exchange (ETDEWEB)

    Bhaduri, Budhendra L [ORNL; Bright, Eddie A [ORNL; Rose, Amy N [ORNL; Liu, Cheng [ORNL; Urban, Marie L [ORNL; Stewart, Robert N [ORNL

    2014-01-01

    High resolution population distribution data are vital for successfully addressing critical issues ranging from energy and socio-environmental research to public health to human security. Commonly available population data from Census is constrained both in space and time and does not capture population dynamics as functions of space and time. This imposes a significant limitation on the fidelity of event-based simulation models with sensitive space-time resolution. This paper describes ongoing development of high-resolution population distribution and dynamics models, at Oak Ridge National Laboratory, through spatial data integration and modeling with behavioral or activity-based mobility datasets for representing temporal dynamics of population. The model is resolved at 1 km resolution globally and describes the U.S. population for nighttime and daytime at 90m. Integration of such population data provides the opportunity to develop simulations and applications in critical infrastructure management from local to global scales.

  11. Construction of a high resolution microscope with conventional and holographic optical trapping capabilities.

    Science.gov (United States)

    Butterfield, Jacqualine; Hong, Weili; Mershon, Leslie; Vershinin, Michael

    2013-04-22

    High resolution microscope systems with optical traps allow for precise manipulation of various refractive objects, such as dielectric beads (1) or cellular organelles (2,3), as well as for high spatial and temporal resolution readout of their position relative to the center of the trap. The system described herein has one such "traditional" trap operating at 980 nm. It additionally provides a second optical trapping system that uses a commercially available holographic package to simultaneously create and manipulate complex trapping patterns in the field of view of the microscope (4,5) at a wavelength of 1,064 nm. The combination of the two systems allows for the manipulation of multiple refractive objects at the same time while simultaneously conducting high speed and high resolution measurements of motion and force production at nanometer and piconewton scale.

  12. Very high resolution crop surface models (CSMs) from UAV-based stereo images for rice growth monitoring In Northeast China

    OpenAIRE

    Bendig, J.; Willkomm, M; N. Tilly; M. L. Gnyp; S. Bennertz; Qiang, C.; Y. Miao; Lenz-Wiedemann, V. I. S.; G. Bareth

    2013-01-01

    Unmanned aerial vehicles (UAVs) became popular platforms for the collection of remotely sensed geodata in the last years (Hardin & Jensen 2011). Various applications in numerous fields of research like archaeology (Hendrickx et al., 2011), forestry or geomorphology evolved (Martinsanz, 2012). This contribution deals with the generation of multi-temporal crop surface models (CSMs) with very high resolution by means of low-cost equipment. The concept of the generation of multi-temporal...

  13. High Resolution Ionospheric Mapping Using Spaceborne Synthetic Aperture Radars

    Science.gov (United States)

    Meyer, F. J.; Chotoo, K.; Roth, A. P.

    2012-12-01

    properties, and (if applicable) geographic location. Three case studies will be presented to highlight the type and quality of ionospheric information that can be retrieved: (1) The high spatial resolution of SAR-derived TEC maps is emphasized in a case study that focuses on high resolution mapping of aurora arcs in central Alaska. Here, TEC enhancements associated with aurora activity are mapped and compared to reference observations from sky cameras and GPS; (2) observations of mid-latitudal traveling ionospheric disturbances are shown to showcase the accuracy of SAR-derived TEC maps. Several SAR-based TEC mapping methods are compared to highlight their respective advantages and disadvantages regarding processing complexity and estimation accuracy; (3) a third example focuses on analyzing post-sunset scintillation phenomena in equatorial regions. SAR is used to assess the frequency of occurrence of scintillation and analyze their associated power spectra. To conclude the paper, the temporal and spatial sampling of the ionosphere provided by the fleet of current and future spaceborne SAR sensors is analyzed to provide an assessment of the global ionospheric mapping capabilities of SAR.

  14. Spatially adaptive regularized iterative high-resolution image reconstruction algorithm

    Science.gov (United States)

    Lim, Won Bae; Park, Min K.; Kang, Moon Gi

    2000-12-01

    High resolution images are often required in applications such as remote sensing, frame freeze in video, military and medical imaging. Digital image sensor arrays, which are used for image acquisition in many imaging systems, are not dense enough to prevent aliasing, so the acquired images will be degraded by aliasing effects. To prevent aliasing without loss of resolution, a dense detector array is required. But it may be very costly or unavailable, thus, many imaging systems are designed to allow some level of aliasing during image acquisition. The purpose of our work is to reconstruct an unaliased high resolution image from the acquired aliased image sequence. In this paper, we propose a spatially adaptive regularized iterative high resolution image reconstruction algorithm for blurred, noisy and down-sampled image sequences. The proposed approach is based on a Constrained Least Squares (CLS) high resolution reconstruction algorithm, with spatially adaptive regularization operators and parameters. These regularization terms are shown to improve the reconstructed image quality by forcing smoothness, while preserving edges in the reconstructed high resolution image. Accurate sub-pixel motion registration is the key of the success of the high resolution image reconstruction algorithm. However, sub-pixel motion registration may have some level of registration error. Therefore, a reconstruction algorithm which is robust against the registration error is required. The registration algorithm uses a gradient based sub-pixel motion estimator which provides shift information for each of the recorded frames. The proposed algorithm is based on a technique of high resolution image reconstruction, and it solves spatially adaptive regularized constrained least square minimization functionals. In this paper, we show that the reconstruction algorithm gives dramatic improvements in the resolution of the reconstructed image and is effective in handling the aliased information. The

  15. High resolution mesospheric sodium properties for adaptive optics applications

    Science.gov (United States)

    Pfrommer, T.; Hickson, P.

    2014-05-01

    Context. The performance of laser guide star adaptive optics (AO) systems for large optical and infrared telescopes is affected by variability of the sodium layer, located at altitudes between 80 and 120 km in the upper mesosphere and lower thermosphere. The abundance and density structure of the atomic sodium found in this region is subject to local and global weather effects, planetary and gravity waves and magnetic storms, and is variable on time scales down to tens of milliseconds, a range relevant to AO. Aims: It is therefore important to characterize the structure and dynamical evolution of the sodium region on small, as well as large spatial and temporal scales. Parameters of particular importance for AO are the mean sodium altitude, sodium layer width and the temporal power spectrum of the centroid altitude. Methods: We have conducted a three-year campaign employing a high-resolution lidar system installed on the 6-m Large Zenith Telescope (LZT) located near Vancouver, Canada. During this period, 112 nights of useful data were obtained. Results: The vertical density profile of atomic sodium shows remarkable structure and variability. Smooth Gaussian-shaped profiles rarely occur. Multiple internal layers are frequently found. These layers often have sharp lower edges, with scale heights of just a few hundred meters, and tend to drift downwards at a typical rate of one kilometer every two to three hours. Individual layers can persist for many hours, but their density and internal structure can be highly variable. Sporadic layers are seen reaching peak densities several times the average, often in just a few minutes. Coherent vertical oscillations are often found, typically extending over tens of kilometers in altitude. Regions of turbulence are evident and Kelvin-Helmholtz instability are sometimes seen. The mean value of the centroid altitude is found to be 90.8 ± 0.1 km. The sodium layer width was determined by computing the altitude range that contains a

  16. Non-Invasive Monitoring of Temporal and Spatial Blood Flow during Bone Graft Healing Using Diffuse Correlation Spectroscopy.

    Directory of Open Access Journals (Sweden)

    Songfeng Han

    Full Text Available Vascular infiltration and associated alterations in microvascular blood flow are critical for complete bone graft healing. Therefore, real-time, longitudinal measurement of blood flow has the potential to successfully predict graft healing outcomes. Herein, we non-invasively measure longitudinal blood flow changes in bone autografts and allografts using diffuse correlation spectroscopy in a murine femoral segmental defect model. Blood flow was measured at several positions proximal and distal to the graft site before implantation and every week post-implantation for a total of 9 weeks (autograft n = 7 and allograft n = 10. Measurements of the ipsilateral leg with the graft were compared with those of the intact contralateral control leg. Both autografts and allografts exhibited an initial increase in blood flow followed by a gradual return to baseline levels. Blood flow elevation lasted up to 2 weeks in autografts, but this duration varied from 2 to 6 weeks in allografts depending on the spatial location of the measurement. Intact contralateral control leg blood flow remained at baseline levels throughout the 9 weeks in the autograft group; however, in the allograft group, blood flow followed a similar trend to the graft leg. Blood flow difference between the graft and contralateral legs (ΔrBF, a parameter defined to estimate graft-specific changes, was elevated at 1-2 weeks for the autograft group, and at 2-4 weeks for the allograft group at the proximal and the central locations. However, distal to the graft, the allograft group exhibited significantly greater ΔrBF than the autograft group at 3 weeks post-surgery (p < 0.05. These spatial and temporal differences in blood flow supports established trends of delayed healing in allografts versus autografts.

  17. The role of angiography in managing patients with temporal bone fractures: a retrospective study of 64 cases.

    Science.gov (United States)

    Ahmed, K Asif; Alison, David; Whatley, Wesley S; Chandra, Rakesh K

    2009-05-01

    We conducted a retrospective study of the utility of angiography in the evaluation of patients with temporal bone fractures. Our study population was made up of 64 patients-58 males and 6 females, aged 14 to 75 years (mean: 35.3)-with a temporal bone fracture who had presented to a level I trauma center over a 1-year period. Records were reviewed and data were obtained on the mechanism of injury; the type of fracture; associated injuries, particularly neurocranial injuries detected on computed tomography (CT) of the head; and any angiographic findings that might have been obtained. The primary outcomes measures were the type of treatment administered (conservative vs. surgical) and mortality. Patients were assigned to 1 of 4 groups according to CT results and angiographic findings, if any: normal CT and no angiogram (group 1; n = 12), abnormal CT and no angiogram (group 2; n = 28), abnormal CT and an abnormal angiogram (group 3; n = 9), and abnormal CT and a normal angiogram (group 4; n = 15). Conservative treatment was administered to all 12 patients in group 1 and to 9 patients (60%) in group 4; surgical treatment was provided to two-thirds of the patients in both group 2 and group 3. Mortality was low in group 1 (n = 0), group 3 (n = 1; 11%), and group 4 (n = 1; 7%), but high in group 2 (n = 10; 36%). In fact, the key finding of this study was that mortality in the group with an abnormal CT and no angiogram (group 2) was significantly higher than mortality in the group with an abnormal CT and an abnormal angiogram (group 3) (p = 0.02), even though the injuries in the 2 groups were similarly severe and their management was similarly aggressive. We conclude that current guidelines for angiography may need to be expanded to include all patients who have CT evidence of neurocranial injury in order to detect those vascular injuries that need aggressive management and thus lower overall mortality.

  18. Design and implementation of spaceborne high resolution infrared touch screen

    Science.gov (United States)

    Li, Tai-guo; Li, Wen-xin; Dong, Yi-peng; Ma, Wen; Xia, Jia-gao

    2015-10-01

    For the consideration of the special application environment of the electronic products used in aerospace and to further more improve the human-computer interaction of the manned aerospace area. The research is based on the design and implementation way of the high resolution spaceborne infrared touch screen on the basis of FPGA and DSP frame structure. Beside the introduction of the whole structure for the high resolution spaceborne infrared touch screen system, this essay also gives the detail information about design of hardware for the high resolution spaceborne infrared touch screen system, FPGA design, GUI design and DSP algorithm design based on Lagrange interpolation. What is more, the easy makes a comprehensive research of the reliability design for the high resolution spaceborne infrared touch screen for the special purpose of it. Besides, the system test is done after installation of spaceborne infrared touch screen. The test result shows that the system is simple and reliable enough, which has a stable running environment and high resolution, which certainly can meet the special requirement of the manned aerospace instrument products.

  19. Is It Necessary to Do Temporal Bone Computed Tomography of the Internal Auditory Canal in Tinnitus with Normal Hearing?

    Directory of Open Access Journals (Sweden)

    Tolgar Lutfi Kumral

    2013-01-01

    Full Text Available Objective. To investigate the compression of the vestibulocochlear nerve in the etiology of the tinnitus in the normal hearing ears with temporal bone computed tomography scans. Methods. A prospective nonrandomized study of 30 bilateral tinnitus and 30 normal hearing patients enrolled in this study. Results. A total of 60 patients (ages ranged from 16 to 87 were included. The tinnitus group comprised 11 males and 19 females (mean age 49,50 ± 12,008 and the control group comprised 6 males and 24 females (mean age 39,47 ± 12,544. Regarding the right and left internal acoustic canals measurements (inlet, midcanal, and outlet canal lengths, there were no significant differences between the measurements of the control and tinnitus groups (P>0.005. There was no narrowness in the internal acoustic canal of the tinnitus group compared with the control group. High-frequency audiometric measurements of the right and left ears tinnitus group at 8000, 9000, 10000, 11200, 12500, 14000, 16000, and 18000 Hz frequencies were significantly lower than the control group thresholds (P<0.05. There was high-frequency hearing loss in the tinnitus group. Conclusion. There were no anatomical differences in the etiology of tinnitus rather than physiological degeneration in the nerves.

  20. Measurement of stapes vibration in Human temporal bones by round window stimulation using a 3-coil transducer.

    Science.gov (United States)

    Shin, Dong Ho; Kim, Dong Wook; Lim, Hyung Gyu; Jung, Eui Sung; Seong, Ki Woong; Lee, Jyung Hyun; Kim, Myoung Nam; Cho, Jin Ho

    2014-01-01

    Round window placement of a 3-coil transducer offers a new approach for coupling an implantable hearing aid to the inner ear. The transducer exhibits high performance at low-frequencies. One remarkable feature of the 3-coil transducer is that it minimizes leakage flux. Thus, the transducer, which consists of two permanent magnets and three coils, can enhance vibrational displacement. In human temporal bones, stapes vibration was observed by laser Doppler vibrometer in response to round window stimulation using the 3-coil transducer. Coupling between the 3-coil transducer and the round window was connected by a wire-rod. The stimulation created stapes velocity when the round window stimulated. Performance evaluation was conducted by measuring stapes velocity. To verify the performance of the 3-coil transducer, stapes velocity for round window and tympanic membrane stimulation were compared, respectively. Stapes velocity by round window stimulation using the 3-coil transducer was approximately 14 dB higher than that achieved by tympanic membrane stimulation. The study shows that 3-coil transducer is suitable for implantable hearing aids.

  1. Inclusion body myopathy, Paget's disease of the bone and fronto-temporal dementia: a disorder of autophagy.

    Science.gov (United States)

    Ju, Jeong-Sun; Weihl, Conrad C

    2010-04-15

    Inclusion body myopathy associated with Paget's disease of the bone and fronto-temporal dementia (IBMPFD) is a progressive autosomal dominant disorder caused by mutations in p97/VCP (valosin-containing protein). p97/VCP is a member of the AAA+ (ATPase associated with a variety of activities) protein family and participates in multiple cellular processes. One particularly important role for p97/VCP is facilitating intracellular protein degradation. p97/VCP has traditionally been thought to mediate the ubiquitin-proteasome degradation of proteins; however, recent studies challenge this dogma. p97/VCP clearly participates in the degradation of aggregate-prone proteins, a process principally mediated by autophagy. In addition, IBMPFD mutations in p97/VCP lead to accumulation of autophagic structures in patient and transgenic animal tissue. This is likely due to a defect in p97/VCP-mediated autophagosome maturation. The following review will discuss the evidence for p97/VCP in autophagy and how a disruption in this process contributes to IBMPFD pathogenesis.

  2. Different temporal patterns in the expressions of bone morphogenetic proteins and noggin during astroglial scar formation after ischemic stroke.

    Science.gov (United States)

    Shin, Jin A; Kang, Jihee Lee; Lee, Kyung-Eun; Park, Eun-Mi

    2012-05-01

    Bone morphogenetic proteins (BMPs) and their antagonists have roles in scar formation and regeneration after central nervous system injuries. However, temporal changes in their expression during astroglial scar formation in the ischemic brain are unknown. Here, we examined protein levels of BMP2, BMP7, and their antagonist noggin in the ischemic brain up to 4 weeks after experimental stroke in mice. BMP2 and BMP7 levels were increased from 1 to 4 weeks in the ischemic brain, and their expression was associated with astrogliosis. BMP7 expression was more intense and co-localized in reactive astrocytes in the ischemic subcortex at 1 week. Noggin expression began to increase after 2 weeks and was further increased at 4 weeks only in the ischemic subcortex, but the intensity was weak compared to the intensity of BMPs. Noggin was co-localized mainly in activated microglia. These findings show that expression of BMPs and noggin differed over time, in intensity and in types of cell, and suggest that BMPs and noggin have different roles in the processes of glial scar formation and neurorestoration in the ischemic brain.

  3. Compact and high-resolution optical orbital angular momentum sorter

    Directory of Open Access Journals (Sweden)

    Chenhao Wan

    2017-03-01

    Full Text Available A compact and high-resolution optical orbital angular momentum (OAM sorter is proposed and demonstrated. The sorter comprises a quadratic fan-out mapper and a dual-phase corrector positioned in the pupil plane and the Fourier plane, respectively. The optical system is greatly simplified compared to previous demonstrations of OAM sorting, and the performance in resolution and efficiency is maintained. A folded configuration is set up using a single reflective spatial light modulator (SLM to demonstrate the validity of the scheme. The two phase elements are implemented on the left and right halves of the SLM and connected by a right-angle prism. Experimental results demonstrate the high resolution of the compact OAM sorter, and the current limit in efficiency can be overcome by replacing with transmissive SLMs and removing the beam splitters. This novel scheme paves the way for the miniaturization and integration of high-resolution OAM sorters.

  4. High-resolution SPECT for small-animal imaging

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    This article presents a brief overview of the development of high-resolution SPECT for small-animal imaging. A pinhole collimator has been used for high-resolution animal SPECT to provide better spatial resolution and detection efficiency in comparison with a parallel-hole collimator. The theory of imaging characteristics of the pinhole collimator is presented and the designs of the pinhole aperture are discussed. The detector technologies used for the development of small-animal SPECT and the recent advances are presented. The evolving trend of small-animal SPECT is toward a multi-pinhole and a multi-detector system to obtain a high resolution and also a high detection efficiency.

  5. High resolution single particle refinement in EMAN2.1.

    Science.gov (United States)

    Bell, James M; Chen, Muyuan; Baldwin, Philip R; Ludtke, Steven J

    2016-05-01

    EMAN2.1 is a complete image processing suite for quantitative analysis of grayscale images, with a primary focus on transmission electron microscopy, with complete workflows for performing high resolution single particle reconstruction, 2-D and 3-D heterogeneity analysis, random conical tilt reconstruction and subtomogram averaging, among other tasks. In this manuscript we provide the first detailed description of the high resolution single particle analysis pipeline and the philosophy behind its approach to the reconstruction problem. High resolution refinement is a fully automated process, and involves an advanced set of heuristics to select optimal algorithms for each specific refinement task. A gold standard FSC is produced automatically as part of refinement, providing a robust resolution estimate for the final map, and this is used to optimally filter the final CTF phase and amplitude corrected structure. Additional methods are in-place to reduce model bias during refinement, and to permit cross-validation using other computational methods.

  6. A high-resolution vehicle emission inventory for China

    Science.gov (United States)

    Zheng, B.; Zhang, Q.; He, K.; Huo, H.; Yao, Z.; Wang, X.

    2012-12-01

    Developing high resolution emission inventory is an essential task for air quality modeling and management. However, current vehicle emission inventories in China are usually developed at provincial level and then allocated to grids based on various spatial surrogates, which is difficult to get high spatial resolution. In this work, we developed a new approach to construct a high-resolution vehicle emission inventory for China. First, vehicle population at county level were estimated by using the relationship between per-capita GDP and vehicle ownership. Then the Weather Research and Forecasting (WRF) model were used to drive the International Vehicle Emission (IVE) model to get monthly emission factors for each county. Finally, vehicle emissions by county were allocated to grids with 5-km horizon resolution by using high-resolution road network data. This work provides a better understanding of spatial representation of vehicle emissions in China and can benefit both air quality modeling and management with improved spatial accuracy.

  7. High-resolution low-dose scanning transmission electron microscopy.

    Science.gov (United States)

    Buban, James P; Ramasse, Quentin; Gipson, Bryant; Browning, Nigel D; Stahlberg, Henning

    2010-01-01

    During the past two decades instrumentation in scanning transmission electron microscopy (STEM) has pushed toward higher intensity electron probes to increase the signal-to-noise ratio of recorded images. While this is suitable for robust specimens, biological specimens require a much reduced electron dose for high-resolution imaging. We describe here protocols for low-dose STEM image recording with a conventional field-emission gun STEM, while maintaining the high-resolution capability of the instrument. Our findings show that a combination of reduced pixel dwell time and reduced gun current can achieve radiation doses comparable to low-dose TEM.

  8. Novel techniques in VUV high-resolution spectroscopy

    CERN Document Server

    Ubachs, W; Eikema, K S E; de Oliveira, N; Nahon, L

    2013-01-01

    Novel VUV sources and techniques for VUV spectroscopy are reviewed. Laser-based VUV sources have been developed via non-linear upconversion of laser pulses in the nanosecond (ns), the picosecond (ps), and femtosecond (fs) domain, and are applied in high-resolution gas phase spectroscopic studies. While the ns and ps pulsed laser sources, at Fourier-transform limited bandwidths, are used in wavelength scanning spectroscopy, the fs laser source is used in a two-pulse time delayed mode. In addition a Fourier-transform spectrometer for high resolution gas-phase spectroscopic studies in the VUV is described, exhibiting the multiplex advantage to measure many resonances simultaneously.

  9. High-resolution spectroscopy of gases for industrial applications

    DEFF Research Database (Denmark)

    Fateev, Alexander; Clausen, Sønnik

    High-resolution spectroscopy of gases is a powerful technique which has various fundamental and practical applications: in situ simultaneous measurements of gas temperature and gas composition, radiative transfer modeling, validation of existing and developing of new databases and etc. Existing...... for analysis of complex experimental data and further development of the databases. High-temperature gas cell facilities available at DTU Chemical Engineering are presented and described. The gas cells and high-resolution spectrometers allow us to perform high-quality reference measurements of gases relevant...

  10. INTERACTIVE CHANGE DETECTION USING HIGH RESOLUTION REMOTE SENSING IMAGES BASED ON ACTIVE LEARNING WITH GAUSSIAN PROCESSES

    Directory of Open Access Journals (Sweden)

    H. Ru

    2016-06-01

    Full Text Available Although there have been many studies for change detection, the effective and efficient use of high resolution remote sensing images is still a problem. Conventional supervised methods need lots of annotations to classify the land cover categories and detect their changes. Besides, the training set in supervised methods often has lots of redundant samples without any essential information. In this study, we present a method for interactive change detection using high resolution remote sensing images with active learning to overcome the shortages of existing remote sensing image change detection techniques. In our method, there is no annotation of actual land cover category at the beginning. First, we find a certain number of the most representative objects in unsupervised way. Then, we can detect the change areas from multi-temporal high resolution remote sensing images by active learning with Gaussian processes in an interactive way gradually until the detection results do not change notably. The artificial labelling can be reduced substantially, and a desirable detection result can be obtained in a few iterations. The experiments on Geo-Eye1 and WorldView2 remote sensing images demonstrate the effectiveness and efficiency of our proposed method.

  11. Damage extraction of buildings in the 2015 Gorkha, Nepal earthquake from high-resolution SAR data

    Science.gov (United States)

    Yamazaki, Fumio; Bahri, Rendy; Liu, Wen; Sasagawa, Tadashi

    2016-05-01

    Satellite remote sensing is recognized as one of the effective tools for detecting and monitoring affected areas due to natural disasters. Since SAR sensors can capture images not only at daytime but also at nighttime and under cloud-cover conditions, they are especially useful at an emergency response period. In this study, multi-temporal high-resolution TerraSAR-X images were used for damage inspection of the Kathmandu area, which was severely affected by the April 25, 2015 Gorkha Earthquake. The SAR images obtained before and after the earthquake were utilized for calculating the difference and correlation coefficient of backscatter. The affected areas were identified by high values of the absolute difference and low values of the correlation coefficient. The post-event high-resolution optical satellite images were employed as ground truth data to verify our results. Although it was difficult to estimate the damage levels for individual buildings, the high resolution SAR images could illustrate their capability in detecting collapsed buildings at emergency response times.

  12. A DVD Spectroscope: A Simple, High-Resolution Classroom Spectroscope

    Science.gov (United States)

    Wakabayashi, Fumitaka; Hamada, Kiyohito

    2006-01-01

    Digital versatile disks (DVDs) have successfully made up an inexpensive but high-resolution spectroscope suitable for classroom experiments that can easily be made with common material and gives clear and fine spectra of various light sources and colored material. The observed spectra can be photographed with a digital camera, and such images can…

  13. High-resolution TFT-LCD for spatial light modulator

    Science.gov (United States)

    Lee, JaeWon; Kim, Yong-Hae; Byun, Chun-Won; Pi, Jae-Eun; Oh, Himchan; Kim, GiHeon; Lee, Myung-Lae; Chu, Hye-Yong; Hwang, Chi-Sun

    2014-06-01

    SLM with very fine pixel pitch is needed for the holographic display system. Among various kinds of SLMs, commercially available high resolution LCoS has been widely used as a spatial light modulator. But the size of commercially available LCoS SLM is limited because the manufacturing technology of LCoS is based on the semiconductor process developed on small size Si wafer. Recently very high resolution flat panel display panel (~500ppi) was developed as a "retina display". Until now, the pixel pitch of flat panel display is several times larger than the pixel pitch of LCoS. But considering the possibility of shrink down the pixel pitch with advanced lithographic tools, the application of flat panel display will make it possible to build a SLM with high spatial bandwidth product. We simulated High resolution TFT-LCD panel on glass substrate using oxide semiconductor TFT with pixel pitch of 20um. And we considered phase modulation behavior of LC(ECB) mode. The TFT-LCD panel is reflective type with 4-metal structure with organic planarization layers. The technical challenge for high resolution large area SLM will be discussed with very fine pixel.

  14. High resolution positron tomography using PCR-I

    Energy Technology Data Exchange (ETDEWEB)

    Brownell, G.L.; Burnham, C.A.; Sandrew, B.; Elmaleh, D.R.; Livni, E.; Kizuka, H.

    1984-01-01

    PCR-I is a high resolution positron tomograph developed by the Physics Research Laboratory of the Massachusetts General Hospital to explore resolution limits of positron tomographs. PCR-I currently obtains images with 4.8 mm FWHM resolution at the center. Plane thickness may be varied between 5 and 10 mm. The instrument uses analog coding to obtain high resolution images without mechanical motion. This permits rapid dynamic imaging and gated cardiac imaging as well as conventional high resolution imaging. A series of studies has been carried out to demonstrate the ability of PCR-I to image structures in small animals. F-18 in the rat skeleton is clearly defined and various structures such as the spinal processes can be clearly resolved. A sequence of images at different spacing provides a three-dimensional reconstruction of the rat skeleton. Blood volume and palmitic acid have been imaged in the dog heart. Again, the sequence of images provides a clear delineation of the three dimensional nature of the blood pools and of the surrounding musculature. Blood flow, blood volume and glucose metabolism have been studied in the monkey brain. Structures within the brain of the Resus monkey can be clearly resolved. Increased activity resulting from induced seizures in the squirrel monkey have been observed and delineated. All of these studies indicate areas of future animal and clinical research using the high resolution tomograph, PCR-I.

  15. A Large Scale, High Resolution Agent-Based Insurgency Model

    Science.gov (United States)

    2013-09-30

    2007). HSCB Models can be employed for simulating mission scenarios, determining optimal strategies for disrupting terrorist networks, or training and...High Resolution Agent-Based Insurgency Model ∑ = ⎜ ⎜ ⎝ ⎛ − −− = desired 1 move,desired, desired,,desired, desired,, N j ij jmoveij moveiD rp prp

  16. Towards high resolution data assimilation and ensemble forecasting

    NARCIS (Netherlands)

    Stappers, R.J.J.

    2013-01-01

    Due the increase in computational power of supercomputers the grid resolution of high resolution numerical weather prediction models is now reaching the 1 km scale. As a result, mesoscale processes related to high impact weather (such as deep convection) can now explicitly be resolved by the models.

  17. Workshop on high-resolution, large-acceptance spectrometers

    Energy Technology Data Exchange (ETDEWEB)

    Zeidman, B. (ed.)

    1981-01-01

    The purpose of the Workshop on High-Resolution, Large-Acceptance Spectrometers was to provide a means for exchange of information among those actively engaged in the design and construction of these new spectrometers. Thirty-seven papers were prepared for the data base.

  18. Remote parallel rendering for high-resolution tiled display walls

    KAUST Repository

    Nachbaur, Daniel

    2014-11-01

    © 2014 IEEE. We present a complete, robust and simple to use hardware and software stack delivering remote parallel rendering of complex geometrical and volumetric models to high resolution tiled display walls in a production environment. We describe the setup and configuration, present preliminary benchmarks showing interactive framerates, and describe our contributions for a seamless integration of all the software components.

  19. High resolution STEM of quantum dots and quantum wires

    DEFF Research Database (Denmark)

    Kadkhodazadeh, Shima

    2013-01-01

    This article reviews the application of high resolution scanning transmission electron microscopy (STEM) to semiconductor quantum dots (QDs) and quantum wires (QWRs). Different imaging and analytical techniques in STEM are introduced and key examples of their application to QDs and QWRs...

  20. Structure Identification in High-Resolution Transmission Electron Microscopic Images

    DEFF Research Database (Denmark)

    Vestergaard, Jacob Schack; Kling, Jens; Dahl, Anders Bjorholm

    2014-01-01

    A connection between microscopic structure and macroscopic properties is expected for almost all material systems. High-resolution transmission electron microscopy is a technique offering insight into the atomic structure, but the analysis of large image series can be time consuming. The present ...

  1. Developing Visual Editors for High-Resolution Haptic Patterns

    DEFF Research Database (Denmark)

    Cuartielles, David; Göransson, Andreas; Olsson, Tony;

    2012-01-01

    In this article we give an overview of our iterative work in developing visual editors for creating high resolution haptic patterns to be used in wearable, haptic feedback devices. During the past four years we have found the need to address the question of how to represent, construct and edit high...

  2. Signal Processing for High Resolution FMCW SAR and Moving Target

    NARCIS (Netherlands)

    Meta, A.; Hoogeboom, P.

    2005-01-01

    The combination of Frequency Modulated ContinuousWave (FMCW) technology and Synthetic Aperture Radar (SAR) leads to lightweight, cost-effective imaging sensors of high resolution. In FMCW SAR applications the conventional stop-and-go approximation used in pulse radar algorithms cannot be considered

  3. High Resolution Digital Imaging of Paintings: The Vasari Project.

    Science.gov (United States)

    Martinez, Kirk

    1991-01-01

    Describes VASARI (the Visual Art System for Archiving and Retrieval of Images), a project funded by the European Community to show the feasibility of high resolution colormetric imaging directly from paintings. The hardware and software used in the system are explained, storage on optical disks is described, and initial results are reported. (five…

  4. Ultra-high-resolution small-animal SPECT imaging

    NARCIS (Netherlands)

    Have, F. van der

    2007-01-01

    The main subject of this thesis is the development of the first two in a series of dedicated ultra-high resolution Single Photon Emission Computed Tomography (SPECT) systems (U-SPECT-I and II) for the imaging of distributions of radio-isotope labeled tracers in small laboratory animals such as mice

  5. Evacuee Compliance Behavior Analysis using High Resolution Demographic Information

    Energy Technology Data Exchange (ETDEWEB)

    Lu, Wei [ORNL; Han, Lee [University of Tennessee, Knoxville (UTK); Liu, Cheng [ORNL; Tuttle, Mark A [ORNL; Bhaduri, Budhendra L [ORNL

    2014-01-01

    The purpose of this study is to examine whether evacuee compliance behavior with route assignments from different resolutions of demographic data would impact the evacuation performance. Most existing evacuation strategies assume that travelers will follow evacuation instructions, while in reality a certain percent of evacuees do not comply with prescribed instructions. In this paper, a comparison study of evacuation assignment based on Traffic Analysis Zones (TAZ) and high resolution LandScan USA Population Cells (LPC) were conducted for the detailed road network representing Alexandria, Virginia. A revised platform for evacuation modeling built on high resolution demographic data and activity-based microscopic traffic simulation is proposed. The results indicate that evacuee compliance behavior affects evacuation efficiency with traditional TAZ assignment, but it does not significantly compromise the efficiency with high resolution LPC assignment. The TAZ assignment also underestimates the real travel time during evacuation, especially for high compliance simulations. This suggests that conventional evacuation studies based on TAZ assignment might not be effective at providing efficient guidance to evacuees. From the high resolution data perspective, traveler compliance behavior is an important factor but it does not impact the system performance significantly. The highlight of evacuee compliance behavior analysis should be emphasized on individual evacuee level route/shelter assignments, rather than the whole system performance.

  6. HIGH RESOLUTION RESISTIVITY LEAK DETECTION DATA PROCESSING & EVALUATION MEHTODS & REQUIREMENTS

    Energy Technology Data Exchange (ETDEWEB)

    SCHOFIELD JS

    2007-10-04

    This document has two purposes: {sm_bullet} Describe how data generated by High Resolution REsistivity (HRR) leak detection (LD) systems deployed during single-shell tank (SST) waste retrieval operations are processed and evaluated. {sm_bullet} Provide the basic review requirements for HRR data when Hrr is deployed as a leak detection method during SST waste retrievals.

  7. High resolution ultrasonography in isolated soft tissue and intramuscular cysticercosis

    Directory of Open Access Journals (Sweden)

    Gaurav Sharma

    2016-01-01

    Conclusions: With the advent of high resolution ultrasonography and increased clinical awareness of the isolated soft tissue-intramuscular cysticercosis especially in endemic zone, a more conservative non-invasive approach can be applied both in diagnosis and treatment of these isolated cases of cysticercosis. [Int J Res Med Sci 2016; 4(1.000: 42-46

  8. Vehicle Detection and Classification from High Resolution Satellite Images

    Science.gov (United States)

    Abraham, L.; Sasikumar, M.

    2014-11-01

    In the past decades satellite imagery has been used successfully for weather forecasting, geographical and geological applications. Low resolution satellite images are sufficient for these sorts of applications. But the technological developments in the field of satellite imaging provide high resolution sensors which expands its field of application. Thus the High Resolution Satellite Imagery (HRSI) proved to be a suitable alternative to aerial photogrammetric data to provide a new data source for object detection. Since the traffic rates in developing countries are enormously increasing, vehicle detection from satellite data will be a better choice for automating such systems. In this work, a novel technique for vehicle detection from the images obtained from high resolution sensors is proposed. Though we are using high resolution images, vehicles are seen only as tiny spots, difficult to distinguish from the background. But we are able to obtain a detection rate not less than 0.9. Thereafter we classify the detected vehicles into cars and trucks and find the count of them.

  9. Systematic high-resolution assessment of global hydropower potential

    NARCIS (Netherlands)

    Hoes, Olivier A C; Meijer, Lourens J J; Van Der Ent, Ruud J.; Van De Giesen, Nick C.

    2017-01-01

    Population growth, increasing energy demand and the depletion of fossil fuel reserves necessitate a search for sustainable alternatives for electricity generation. Hydropower could replace a large part of the contribution of gas and oil to the present energy mix. However, previous high-resolution

  10. High-resolution radio imaging of young supernovae

    CERN Document Server

    Pérez-Torres, M A; Alberdi, A; Ros, E; Guirado, J C; Lara, L; Mantovani, F; Stockdale, C J; Weiler, K W; Diamond, P J; Van Dyk, S D; Lundqvist, P; Panagia, N; Shapiro, I I; Sramek, R

    2004-01-01

    The high resolution obtained through the use of VLBI gives an unique opportunity to directly observe the interaction of an expanding radio supernova with its surrounding medium. We present here results from our VLBI observations of the young supernovae SN 1979C, SN 1986J, and SN 2001gd.

  11. High-resolution palaeoclimatology of the last millennium

    DEFF Research Database (Denmark)

    Vinther, Bo Møllesøe; Jones, P.D.; Briffa, K.R.

    2009-01-01

    Palaeoclimatology • high-resolution • last millennium • tree rings • dendroclimatology • chronology • uncertainty • corals • ice-cores • speleothems • documentary evidence • instrumental records • varves • borehole temperature • marine sediments • composite plus scaling • CPS • climate field...

  12. High resolution SPM imaging of organic molecules with functionalized tips

    Science.gov (United States)

    Jelínek, Pavel

    2017-08-01

    One of the most remarkable and exciting achievements in the field of scanning probe microscopy (SPM) in the last years is the unprecedented sub-molecular resolution of both atomic and electronic structures of single molecules deposited on solid state surfaces. Despite its youth, the technique has already brought many new possibilities to perform different kinds of measurements, which cannot be accomplished by other techniques. This opens new perspectives in advanced characterization of physical and chemical processes and properties of molecular structures on surfaces. Here, we discuss the history and recent progress of the high resolution imaging with a functionalized probe by means of atomic force microscopy (AFM), scanning tunnelling microscopy (STM) and inelastic electron tunneling spectroscopy (IETS). We describe the mechanisms responsible for the high-resolution AFM, STM and IETS-STM contrast. The complexity of this technique requires new theoretical approaches, where a relaxation of the functionalized probe is considered. We emphasise the similarities of the mechanism driving high-resolution SPM with other imaging methods. We also summarise briefly significant achievements and progress in different branches. Finally we provide brief perspectives and remaining challenges of the further refinement of these high-resolution methods.

  13. The research of road and vehicle information extraction algorithm based on high resolution remote sensing image

    Science.gov (United States)

    Zhou, Tingting; Gu, Lingjia; Ren, Ruizhi; Cao, Qiong

    2016-09-01

    With the rapid development of remote sensing technology, the spatial resolution and temporal resolution of satellite imagery also have a huge increase. Meanwhile, High-spatial-resolution images are becoming increasingly popular for commercial applications. The remote sensing image technology has broad application prospects in intelligent traffic. Compared with traditional traffic information collection methods, vehicle information extraction using high-resolution remote sensing image has the advantages of high resolution and wide coverage. This has great guiding significance to urban planning, transportation management, travel route choice and so on. Firstly, this paper preprocessed the acquired high-resolution multi-spectral and panchromatic remote sensing images. After that, on the one hand, in order to get the optimal thresholding for image segmentation, histogram equalization and linear enhancement technologies were applied into the preprocessing results. On the other hand, considering distribution characteristics of road, the normalized difference vegetation index (NDVI) and normalized difference water index (NDWI) were used to suppress water and vegetation information of preprocessing results. Then, the above two processing result were combined. Finally, the geometric characteristics were used to completed road information extraction. The road vector extracted was used to limit the target vehicle area. Target vehicle extraction was divided into bright vehicles extraction and dark vehicles extraction. Eventually, the extraction results of the two kinds of vehicles were combined to get the final results. The experiment results demonstrated that the proposed algorithm has a high precision for the vehicle information extraction for different high resolution remote sensing images. Among these results, the average fault detection rate was about 5.36%, the average residual rate was about 13.60% and the average accuracy was approximately 91.26%.

  14. Forecast of muddy floods using high-resolution radar precipitation forcasting data and erosion modelling

    Science.gov (United States)

    Hänsel, Phoebe; Schindewolf, Marcus; Schmidt, Jürgen

    2016-04-01

    In the federal province of Saxony, Eastern Germany, almost 60 % of the agricultural land is endangered by erosion processes, mainly caused by heavy rainfall events. Beside the primary impact of soil loss and decreasing soil fertility, erosion can cause significant effects if transported sediments are entering downslope settlements, infrastructure or traffic routes. Available radar precipitation data are closing the gap between the conventional rainfall point measurements and enable the nationwide rainfall distribution with high spatial and temporal resolution. By means of the radar precipitation data of the German Weather Service (DWD), high-resolution radar-based rainfall data totals up to 5 minute time steps are possible. The radar data are visualised in a grid-based hourly precipitation map. In particular, the daily and hourly precipitation maps help to identify regions with heavy rainfall and possible erosion events. In case of an erosion event on agricultural land, these areas are mapped with an unmanned airborne vehicle (UAV). The camera-equipped UAV delivers high-resolution images of the erosion event, that allow the generation of high-resolution orthophotos. By the application of the high-resolution radar precipitation data as an input for the process-based soil loss and deposition model EROSION 3D, these images are for validation purposes. Future research is focused on large scale soil erosion modelling with the help of the radar forecasting product and an automatic identification of sediment pass over points. The study will end up with an user friendly muddy flood warning tool, which allows the local authorities to initiate immediate measures in order to prevent severe damages in settlements, infrastructure or traffic routes.

  15. Dispersal patterns in the North Sea, insights from a high resolution model

    Science.gov (United States)

    Mayorga Adame, Claudia Gabriela; Polton, Jeff; Holt, Jason; Graham, Jennifer; Henry, Lea-Anne

    2017-04-01

    Lagrangian particle tracking simulations are useful to elucidate the fate of materials transported by ocean currents ( i.e. larvae, pollutants, debris, drifters), and can therefore be useful to study important process in coastal seas. Dispersal patterns should be improved by the new generation of high horizontal resolution (ocean circulation models which provide an improved, more dynamic representation of the coastal ocean. We used the new high resolution Northwest European Shelf NEMO ocean circulation model and LTRANS, a particle tracking code, to study the effects of the increased resolution on the dispersion of Lagrangian particles in the North Sea. Particles were released at the locations of offshore oil and gas platforms in the North Sea and tracked for periods similar to the larval duration of benthic organisms that have colonized the subsea platforms. Dispersal patterns and spatio-temporal scales are identified for the summer (stratified) and winter (mixed) oceanographic regimes. The high resolution of the new NEMO model allows for fine scale detail of flow speed and variability. The small scale features (i.e. eddies and fronts) now represented in the model trap particles, decreasing their dispersal and increasing retention times in comparison to simulations done on a previous coarser resolution NEMO version (7 km AMM7). We isolated the effects of resolution from those due to different representations of the circulation in the different versions of the ocean circulation model by averaging the high resolution model velocity fields to the coarser (7 km) grid, and comparing the results of identical particle tracking experiments using these two flow fields. Our results provide a measure of the importance of high resolution flow fields when estimating transport of materials in an enclosed sea and provide a more realistic characterisation of dispersion in the North Sea.

  16. Optical cochlear implant: evaluation of insertion forces of optical fibres in a cochlear model and of traumata in human temporal bones.

    Science.gov (United States)

    Balster, Sven; Wenzel, Gentiana I; Warnecke, Athanasia; Steffens, Melanie; Rettenmaier, Alexander; Zhang, Kaiyin; Lenarz, Thomas; Reuter, Guenter

    2014-02-01

    Optical stimulation for hearing restoration is developing as an alternative therapy to electrical stimulation. For a more frequency-specific activation of the auditory system, light-guiding fibres need to be inserted into the coiled cochlea. To enable insertion with minimal trauma, glass fibres embedded in silicone were used as models. Thus, glass fibres of varying core/cladding diameter with and without silicon coating (single as well as in bundles) were inserted into a human scala tympani (ST) model. Insertion cochlear model force measurements were performed, and the thinner glass fibres that showed low insertion forces in the model were inserted into cadaveric human temporal bones. Silicone-coated glass fibres with different core/cladding diameters and bundle sizes could be inserted up to a maximum depth of 20 mm. Fibres with a core/cladding diameter of 50/55 μm break during insertion deeper than 7-15 mm into the ST model, whereas thinner fibres (20/25 μm) could be inserted in the model without breakage and in human temporal bones without causing trauma to the inner ear structures. The insertion forces of silicone-coated glass fibres are comparable to those measured with conventional cochlear implant (CI) electrodes. As demonstrated in human temporal bones, a minimal traumatic implantation of an optical CI may be considered feasible.

  17. Subcutaneous Cysticercosis: Role of High Resolution Ultrasound in Diagnosis

    Directory of Open Access Journals (Sweden)

    Sachin Lohra

    2014-02-01

    Full Text Available BACKGROUND: Though the commonest site of extraintestinal infestation with Taenia solium is brain, Subcutaneous cysticercosis is fairly common in asia. The advent of high resolution ultrasound, FNAC, and a heightened clinician awareness of the existence of isolated soft tissue cysticerci has probably supplanted the need for surgical intervention and excision biopsy in asymptomatic subcutaneous cysts, as cysts have high rate of spontaneous resolution. OBJECTIVES: - To observe role of high resolution ultrasound in diagnosis and need of surgical intervention in treatment of subcutaneous cysticercosis. MATERIALS and METHODS: retrospective study of seven cases of extraneural cysticercosis, all involving the subcutaneous tissues or muscles over the arms and torso. Either high resolution ultrasound, FNAC, or excision biopsy, or a combination of these were used to arrive at a diagnosis. All patients were followed up with serial ultrasounds. All patients received oral nitazoxanide for autoinfection. Surgical excision was resorted to in two patients, in whom it was possible to obtain a histopathologic diagnosis. RESULTS: of the seven cases of subcutaneous cysticercosis all have rural background, most of the patients (6 were vegetarian and one was non vegetarian. Age and gender of patient, size and duration of lesion were insignificant in establishing the diagnosis. High resolution ultrasound was highly significant in establishing the diagnosis over FNAC and histopathology. Five of the cases resolved spontaneously and surgical intervention was required only in two cases. INTERPRETATION and CONCLUSIONS: With heightened clinician awareness of the existence of isolated subcutaneous cysticercosis in patients with close animal contact, and the widespread availability of high resolution ultrasound and FNAC, subcutaneous cysticercosis can be diagnosed readily. Surgery can be avoided in the great majority of these patients, as the cysts mostly resolve on their own

  18. Multiscaling analysis of high resolution space-time lidar-rainfall

    Directory of Open Access Journals (Sweden)

    P. V. Mandapaka

    2009-09-01

    Full Text Available In this study, we report results from scaling analysis of 2.5 m spatial and 1 s temporal resolution lidar-rainfall data. The high resolution spatial and temporal data from the same observing system allows us to investigate the variability of rainfall at very small scales ranging from few meters to ~1 km in space and few seconds to ~30 min in time. The results suggest multiscaling behaviour in the lidar-rainfall with the scaling regime extending down to the resolution of the data. The results also indicate the existence of a space-time transformation of the form t~Lz at very small scales, where t is the time lag, L is the spatial averaging scale and z is the dynamic scaling exponent.

  19. Developing a high-resolution regional atmospheric reanalysis for Australia

    Science.gov (United States)

    White, Christopher; Fox-Hughes, Paul; Su, Chun-Hsu; Jakob, Dörte; Kociuba, Greg; Eisenberg, Nathan; Steinle, Peter; Harris, Rebecca; Corney, Stuart; Love, Peter; Remenyi, Tomas; Chladil, Mark; Bally, John; Bindoff, Nathan

    2017-04-01

    A dynamically consistent, long-term atmospheric reanalysis can be used to support high-quality assessments of environmental risk and likelihood of extreme events. Most reanalyses are presently based on coarse-scale global systems that are not suitable for regional assessments in fire risk, water and natural resources, amongst others. The Australian Bureau of Meteorology is currently working to close this gap by producing a high-resolution reanalysis over the Australian and New Zealand region to construct a sequence of atmospheric conditions at sub-hourly intervals over the past 25 years from 1990. The Australia reanalysis consists of a convective-scale analysis nested within a 12 km regional-scale reanalysis, which is bounded by a coarse-scale ERA-Interim reanalysis that provides the required boundary and initial conditions. We use an unchanging atmospheric modelling suite based on the UERRA system used at the UK Met Office and the more recent version of the Bureau of Meteorology's operational numerical prediction model used in ACCESS-R (Australian Community Climate and Earth-System Simulator-Regional system). An advanced (4-dimensional variational) data assimilation scheme is used to optimally combine model physics with multiple observations from aircrafts, sondes, surface observations and satellites to create a best estimate of state of the atmosphere over a 6-hour moving window. This analysis is in turn used to drive a higher-resolution (1.5 km) downscaling model over selected subdomains within Australia, currently eastern New South Wales and Tasmania, with the capability to support this anywhere in the Australia-New Zealand domain. The temporal resolution of the gridded analysis fields for both the regional and higher-resolution subdomains are generally one hour, with many fields such as 10 m winds and 2 m temperatures available every 10 minutes. The reanalysis also produces many other variables that include wind, temperature, moisture, pressure, cloud cover

  20. High-resolution DEM Effects on Geophysical Flow Models

    Science.gov (United States)

    Williams, M. R.; Bursik, M. I.; Stefanescu, R. E. R.; Patra, A. K.

    2014-12-01

    Geophysical mass flow models are numerical models that approximate pyroclastic flow events and can be used to assess the volcanic hazards certain areas may face. One such model, TITAN2D, approximates granular-flow physics based on a depth-averaged analytical model using inputs of basal and internal friction, material volume at a coordinate point, and a GIS in the form of a digital elevation model (DEM). The volume of modeled material propagates over the DEM in a way that is governed by the slope and curvature of the DEM surface and the basal and internal friction angles. Results from TITAN2D are highly dependent upon the inputs to the model. Here we focus on a single input: the DEM, which can vary in resolution. High resolution DEMs are advantageous in that they contain more surface details than lower-resolution models, presumably allowing modeled flows to propagate in a way more true to the real surface. However, very high resolution DEMs can create undesirable artifacts in the slope and curvature that corrupt flow calculations. With high-resolution DEMs becoming more widely available and preferable for use, determining the point at which high resolution data is less advantageous compared to lower resolution data becomes important. We find that in cases of high resolution, integer-valued DEMs, very high-resolution is detrimental to good model outputs when moderate-to-low (<10-15°) slope angles are involved. At these slope angles, multiple adjacent DEM cell elevation values are equal due to the need for the DEM to approximate the low slope with a limited set of integer values for elevation. The first derivative of the elevation surface thus becomes zero. In these cases, flow propagation is inhibited by these spurious zero-slope conditions. Here we present evidence for this "terracing effect" from 1) a mathematically defined simulated elevation model, to demonstrate the terracing effects of integer valued data, and 2) a real-world DEM where terracing must be

  1. Analysis of Misdiagnosis of Ossifying Fibroma of the Temporal Bone%颞骨骨化纤维瘤误诊分析

    Institute of Scientific and Technical Information of China (English)

    李红霞; 李晓明; 单珊; 杨泽垠

    2015-01-01

    Objective To summarize the clinical features, diagnostic and differential diagnostic measures of ossifying fibroma of the temporal bone, analyze the cause of misdiagnose, improve the understanding of the disease, and avoid misdiag-nosis and mistreatment. Methods Retrospective analysis of the clinical data of a misdiagnosed case of ossifying fibroma of the temporal bone in our division was carried out. Results The patient was admitted for right ear pain associated with hearing loss for more than two years and tinnitus for four months. The patient had been diagnosed with otitis media in another local hospital. After 6 months of anti-infection and glucocorticoid treatment, improvement of symptoms was not significant. In our hospital, the patient was suspected as having lesions, combining with the history, clinical signs and medical examination. The right temporal bone resection, and infratemporal fossa tumor resection, temporalis muscle flap transfer for repair were per-formed. Postoperative pathology confirmed temporal bone ossifying fibroma. Postoperative hearing improved significantly and tinnitus disappeared. Conclusion The prophase clinical manifestations of temporal bone ossifying fibroma lack specificity and tend to be missed diagnosis and misdiagnosed. Improved awareness of temporal bone ossifying fibroma,careful examinations and system checks may reduce or avoid misdiagnosis and mistreatment of temporal bone ossifying fibroma.%目的:总结颞骨骨化纤维瘤的临床特点、诊断及鉴别诊断措施,提高对其认识,减少误诊误治。方法回顾性分析我科收治的曾误诊为中耳炎的颞骨骨化纤维瘤1例的临床资料。结果患者因右耳疼痛伴听力下降2年余,耳鸣4个月以颞骨肿瘤收住入院。当地医院曾诊断为中耳炎,给予抗感染及糖皮质激素治疗15 d,症状改善不明显,入我院后结合病史、临床特征及医技检查结果,拟诊为颞骨占位性病变,行右侧颞骨部分切除、

  2. Wide-field, high-resolution Fourier ptychographic microscopy

    CERN Document Server

    Zheng, Guoan; Yang, Changhuei

    2014-01-01

    In this article, we report an imaging method, termed Fourier ptychographic microscopy (FPM), which iteratively stitches together a number of variably illuminated, low-resolution intensity images in Fourier space to produce a wide-field, high-resolution complex sample image. By adopting a wavefront correction strategy, the FPM method can also correct for aberrations and digitally extend a microscope's depth-of-focus beyond the physical limitations of its optics. As a demonstration, we built a microscope prototype with a resolution of 0.78 um, a field-of-view of ~120 mm2, and a resolution-invariant depth-of-focus of 0.3 mm (characterized at 632 nm). Gigapixel colour images of histology slides verify FPM's successful operation. The reported imaging procedure transforms the general challenge of high-throughput, high-resolution microscopy from one that is coupled to the physical limitations of the system's optics to one that is solvable through computation.

  3. The Gaia FGK Benchmark Stars - High resolution spectral library

    CERN Document Server

    Blanco-Cuaresma, S; Jofré, P; Heiter, U

    2014-01-01

    Context. An increasing number of high resolution stellar spectra is available today thanks to many past and ongoing spectroscopic surveys. Consequently, numerous methods have been developed in order to perform an automatic spectral analysis on a massive amount of data. When reviewing published results, biases arise and they need to be addressed and minimized. Aims. We are providing a homogeneous library with a common set of calibration stars (known as the Gaia FGK Benchmark Stars) that will allow to assess stellar analysis methods and calibrate spectroscopic surveys. Methods. High resolution and signal-to-noise spectra were compiled from different instruments. We developed an automatic process in order to homogenize the observed data and assess the quality of the resulting library. Results. We built a high quality library that will facilitate the assessment of spectral analyses and the calibration of present and future spectroscopic surveys. The automation of the process minimizes the human subjectivity and e...

  4. High Resolution Muon Computed Tomography at Neutrino Beam Facilities

    CERN Document Server

    Suerfu, Burkhant

    2015-01-01

    X-ray computed tomography (CT) has an indispensable role in constructing 3D images of objects made from light materials. However, limited by absorption coefficients, X-rays cannot deeply penetrate materials such as copper and lead. Here we show via simulation that muon beams can provide high resolution tomographic images of dense objects and of structures within the interior of dense objects. The effects of resolution broadening from multiple scattering diminish with increasing muon momentum. As the momentum of the muon increases, the contrast of the image goes down and therefore requires higher resolution in the muon spectrometer to resolve the image. The variance of the measured muon momentum reaches a minimum and then increases with increasing muon momentum. The impact of the increase in variance is to require a higher integrated muon flux to reduce fluctuations. The flux requirements and level of contrast needed for high resolution muon computed tomography are well matched to the muons produced in the pio...

  5. Design of UAV high resolution image transmission system

    Science.gov (United States)

    Gao, Qiang; Ji, Ming; Pang, Lan; Jiang, Wen-tao; Fan, Pengcheng; Zhang, Xingcheng

    2017-02-01

    In order to solve the problem of the bandwidth limitation of the image transmission system on UAV, a scheme with image compression technology for mini UAV is proposed, based on the requirements of High-definition image transmission system of UAV. The video codec standard H.264 coding module and key technology was analyzed and studied for UAV area video communication. Based on the research of high-resolution image encoding and decoding technique and wireless transmit method, The high-resolution image transmission system was designed on architecture of Android and video codec chip; the constructed system was confirmed by experimentation in laboratory, the bit-rate could be controlled easily, QoS is stable, the low latency could meets most applied requirement not only for military use but also for industrial applications.

  6. High resolution MAS-NMR in combinatorial chemistry.

    Science.gov (United States)

    Shapiro, M J; Gounarides, J S

    High-resolution magic angle spinning (hr-MAS) NMR is a powerful tool for characterizing organic reactions on solid support. Because magic angle spinning reduces the line-broadening due to dipolar coupling and variations in bulk magnetic susceptibility, line widths approaching those obtained in solution-phase NMR can be obtained. The magic angle spinning method is amenable for use in conjunction with a variety of NMR-pulse sequences, making it possible to perform full-structure determinations and conformational analysis on compounds attached to a polymer support. Diffusion-weighted MAS-NMR methods such as SPEEDY (Spin-Echo-Enhanced Diffusion-Filtered Spectroscopy) can be used to remove unwanted signals from the solvent, residual reactants, and the polymer support from the MAS-NMR spectrum, leaving only those signals arising from the resin-bound product. This review will present the applications of high-resolution magic angle spinning NMR for use in combinatorial chemistry research.

  7. High resolution reservoir geological modelling using outcrop information

    Energy Technology Data Exchange (ETDEWEB)

    Zhang Changmin; Lin Kexiang; Liu Huaibo [Jianghan Petroleum Institute, Hubei (China)] [and others

    1997-08-01

    This is China`s first case study of high resolution reservoir geological modelling using outcrop information. The key of the modelling process is to build a prototype model and using the model as a geological knowledge bank. Outcrop information used in geological modelling including seven aspects: (1) Determining the reservoir framework pattern by sedimentary depositional system and facies analysis; (2) Horizontal correlation based on the lower and higher stand duration of the paleo-lake level; (3) Determining the model`s direction based on the paleocurrent statistics; (4) Estimating the sandbody communication by photomosaic and profiles; (6) Estimating reservoir properties distribution within sandbody by lithofacies analysis; and (7) Building the reservoir model in sandbody scale by architectural element analysis and 3-D sampling. A high resolution reservoir geological model of Youshashan oil field has been built by using