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Sample records for resonance arthrography pt

  1. Arthrography

    Medline Plus

    Full Text Available ... joint. Arthrography may use computed tomography (CT) scanning, magnetic resonance imaging (MRI) or fluoroscopy – a form of real- ... methods of direct arthrography examinations may also use magnetic resonance imaging (MRI) or computed tomography (CT) following contrast ...

  2. Arthrography

    Medline Plus

    Full Text Available ... joint. Arthrography may use computed tomography (CT) scanning, magnetic resonance imaging (MRI) or fluoroscopy – a form of real-time x- ... methods of direct arthrography examinations may also use magnetic resonance imaging (MRI) or computed tomography (CT) following contrast material ...

  3. Arthrography

    Medline Plus

    Full Text Available ... joint. Arthrography may use computed tomography (CT) scanning, magnetic resonance imaging (MRI) or fluoroscopy – a form of real-time ... methods of direct arthrography examinations may also use magnetic resonance imaging (MRI) or computed tomography (CT) following contrast material ...

  4. Arthrography

    Medline Plus

    Full Text Available ... is injected into the joint. Arthrography may use computed tomography (CT) scanning, magnetic resonance imaging (MRI) or fluoroscopy – a form of real- ... methods of direct arthrography examinations may also use magnetic resonance ... tomography (CT) following contrast material injection into the joint. ...

  5. Arthrography

    Medline Plus

    Full Text Available ... Z Direct Arthrography Arthrography is a type of medical imaging used to help evaluate and diagnose joint conditions ... Direct Arthrography? What is Direct Arthrography? Arthrography is medical imaging to evaluate conditions of joints. It can either ...

  6. Patient perception of magnetic resonance arthrography

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    Robbins, M.I.; Anzilotti, K.F. Jr.; Katz, L.D.; Lange, R.C. [Dept. of Diagnostic Radiology, Yale University School of Medicine, New Haven, CT (United States)

    2000-05-01

    Objective. Magnetic resonance (MR) arthrography has been demonstrated to be more accurate than MR imaging alone in the identification of a variety of musculoskeletal pathology. While the complication rate of intra-articular gadolinium: saline injection has been shown to be relatively low, MR arthrography is more invasive, painful, and costly, and less convenient, than MR imaging alone. The purpose of this study was to evaluate patients' perception of the fear and discomfort, and to assess their overall acceptance of the intra-articular gadolinium injection.Design and patients. Between October 1997 and January 1998, 113 outpatients who were referred to Yale-New Haven Hospital for MR arthrography of the ankle, elbow, hip, knee, shoulder, or wrist were asked to complete a questionnaire rating their fear of factors most commonly associated with the procedure including ''pain'', ''needles'', ''complications'', and ''discovery of results that would lead to surgery''. In addition, after having undergone the intra-articular gadolinium:saline injection, patients were asked to rate their perception of pain.Results. While many patients expressed fear of ''pain'' and ''needles'', after having undergone the injection their overall pain rating score was low. Only 6% actually found gadolinium arthrography more painful than expected.Conclusion. Despite the fact that patients expressed apprehension about certain aspects of MR arthrography, subjects who underwent the intra-articular gadolinium injection considered the discomfort less than expected. Clinicians should not hesitate to order MR arthrography because the accuracy of the procedure is high enough that patients accept the discomfort. (orig.)

  7. Arthrography

    Medline Plus

    Full Text Available ... What are the limitations of Direct Arthrography? What is Direct Arthrography? Arthrography is medical imaging to evaluate ... ray, CT and ultrasound. top of page How is the procedure performed? This examination is usually done ...

  8. Arthrography

    Medline Plus

    Full Text Available ... a joint abnormality. There are several methods to perform direct arthrography. Conventional direct arthrography of a joint ... to numb the joint area. You may feel pressure or even pain when the needle is advanced ...

  9. Arthrography

    Medline Plus

    Full Text Available ... Your preparation may vary depending on which imaging method your exam will use. Tell your doctor if ... in assessing a joint abnormality. There are several methods to perform direct arthrography. Conventional direct arthrography of ...

  10. Arthrography

    Medline Plus

    Full Text Available ... the joint by a radiologist. Direct arthrography is preferred over indirect arthrography because it distends or enlarges ... MRI scanners are air-conditioned and well-lit. Music may be played through the headphones to help ...

  11. Arthrography

    Medline Plus

    Full Text Available ... Us News Physician Resources Professions Site Index A-Z Direct Arthrography Arthrography is a type of medical ... if possible, or removed prior to the MRI scan. Because they can interfere with the magnetic field ...

  12. Arthrography

    Medline Plus

    Full Text Available ... Your preparation may vary depending on which imaging method your exam will use. Tell your doctor if ... in assessing a joint abnormality. There are several methods to perform direct arthrography. Conventional direct arthrography of ...

  13. Arthrography

    Medline Plus

    Full Text Available ... of the radiation while soft tissue, such as muscle, fat and organs, allow more of the x- ... of arthrography? The limitations of arthrography include: Partial tears of the rotator cuff may not be detected ...

  14. Arthrography

    Medline Plus

    Full Text Available ... vessel or a nerve adjacent to the joint. Injury to these structures, however, is minimal particularly when ... be detected with conventional direct arthrography. Some joint injuries cannot be detected with conventional direct arthrography, including ...

  15. Arthrography

    Medline Plus

    Full Text Available ... Z Direct Arthrography Arthrography is a type of medical imaging used to help evaluate and diagnose joint ... you are pregnant and discuss any recent illnesses, medical conditions, medications you’re taking, and allergies – especially ...

  16. Arthrography

    Medline Plus

    Full Text Available ... vessel or a nerve adjacent to the joint. Injury to these structures, however, is minimal particularly when ... be detected with conventional direct arthrography. Some joint injuries cannot be detected with conventional direct arthrography, including ...

  17. Arthrography

    Medline Plus

    Full Text Available ... conventional direct arthrography and may be supplemented by air to produce a double contrast CT arthrogram. CT ... tissue shows up in shades of gray and air appears black. Until recently, x-ray images were ...

  18. Arthrography

    Medline Plus

    Full Text Available ... and cartilage. It may be indirect, where contrast material is injected into the bloodstream, or direct, where contrast material is injected into the joint. Arthrography may use ...

  19. Arthrography

    Medline Plus

    Full Text Available ... No special preparation is necessary before direct arthrography. Food and fluid intake do not need to be ... to iodine or x-ray contrast material, drugs, food, or environmental agents. However, the contrast material used ...

  20. Arthrography

    Medline Plus

    Full Text Available ... top of page What are the benefits vs. risks? Benefits Direct arthrography is particularly effective for detecting ... used for conventional x-rays and CT scanning. Risks Any procedure where the skin is penetrated carries ...

  1. Arthrography

    Medline Plus

    Full Text Available ... indirect. Indirect arthrography is a medical imaging technique in which contrast material is injected into the blood ... non-arthrographic exam is felt to be inadequate in assessing a joint abnormality. There are several methods ...

  2. Arthrography

    Medline Plus

    Full Text Available ... over time. top of page What are the benefits vs. risks? Benefits Direct arthrography is particularly effective for detecting disease ... cancer from excessive exposure to radiation. However, the benefit of an accurate diagnosis far outweighs the risk. ...

  3. Arthrography

    Medline Plus

    Full Text Available ... Your preparation may vary depending on which imaging method your exam will use. Tell your doctor if ... or indirect. Indirect arthrography is a medical imaging technique in which contrast material is injected into the ...

  4. Arthrography

    Medline Plus

    Full Text Available ... No special preparation is necessary before direct arthrography. Food and fluid intake do not need to be ... to iodine or x-ray contrast material, drugs, food, or environmental agents. However, the contrast material used ...

  5. Arthrography

    Medline Plus

    Full Text Available ... medical imaging to evaluate conditions of joints. It can either be direct or indirect. Indirect arthrography is ... virtually all other internal body structures. The images can then be examined on a computer monitor connected ...

  6. Arthrography

    Medline Plus

    Full Text Available ... felt to be inadequate in assessing a joint abnormality. There are several methods to perform direct arthrography. ... The procedure is most often used to identify abnormalities within the: shoulder elbow wrist hip knee ankle ...

  7. Arthrography

    Medline Plus

    Full Text Available ... preparation is necessary before direct arthrography. Food and fluid intake do not need to be restricted, unless ... a syringe to drain (or aspirate) the joint fluid, which may be sent to a laboratory for ...

  8. Arthrography

    Medline Plus

    Full Text Available ... and unexplained pain. It is very effective at detecting disease within the ligaments, tendons and cartilage. It ... risks? Benefits Direct arthrography is particularly effective for detecting disease of the structures within the joints such ...

  9. Arthrography

    Medline Plus

    Full Text Available ... had surgery. Some conditions, such as severe kidney disease, may prevent you from being given MRI or CT arthrogram contrast material. If you are scheduled to have MR or CT arthrography and have claustrophobia (fear of enclosed spaces) or anxiety, you may want to ask your physician about ...

  10. Arthrography

    Medline Plus

    Full Text Available ... Español More Info Images/Videos About Us News Physician Resources Professions Site Index A-Z Direct Arthrography ... imaging method your exam will use. Tell your doctor if there’s a possibility that you are pregnant ...

  11. Arthrography

    Medline Plus

    Full Text Available ... had surgery. Some conditions, such as severe kidney disease, may prevent you from being given MRI or CT arthrogram contrast material. If you are scheduled to have MR or CT arthrography and have claustrophobia (fear of enclosed spaces) or anxiety, you may want to ask your physician about ...

  12. Review of three magnetic resonance arthrography related infections

    OpenAIRE

    Vollman, Andrew T; Craig, Joseph G; Hulen, Rachel; Ahmed, Abraham; Zervos, Marcus J.; van Holsbeeck, Marnix

    2013-01-01

    We report three cases of intra-articular infection which followed injection for magnetic resonance arthrography. In an effort to reduce the risk of arthrogram related infection, representatives from radiology, infectious disease medicine, and microbiology departments convened to analyze the contributing factors. The proposed source was oral contamination from barium swallow studies which preceded the arthrogram injections in the same room. We propose safety measures to reduce incidence of art...

  13. Review of three magnetic resonance arthrography related infections.

    Science.gov (United States)

    Vollman, Andrew T; Craig, Joseph G; Hulen, Rachel; Ahmed, Abraham; Zervos, Marcus J; van Holsbeeck, Marnix

    2013-02-28

    We report three cases of intra-articular infection which followed injection for magnetic resonance arthrography. In an effort to reduce the risk of arthrogram related infection, representatives from radiology, infectious disease medicine, and microbiology departments convened to analyze the contributing factors. The proposed source was oral contamination from barium swallow studies which preceded the arthrogram injections in the same room. We propose safety measures to reduce incidence of arthrogram related infections.

  14. Intravenous magnetic resonance arthrography of the knee

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Jung Hyeon; Lee, Young Uk; Suh, Jong Dae; Lee, Seung Hee; Kim, Dong Joo [Kangbuk Samsung Hospital, Seoul (Korea, Republic of)

    1995-10-15

    Knee MR images were repeatedly obtained after intravenous administration of gadopentetate dimeglumine to evaluate the arthrographic effect and to determine the optimal scan timing and technique. Sagittal T1-weighted (650/15) sequences were repeated before and after intravenous gadolinium enhancement in 26 patients who were divided into exercise (14/26) and nonexercise (12/26) groups. Fourteen patients in exercise group were allowed to move the affected knee joint actively for 10 minutes immediately after the first post-enhancement scan and before repeating scans. The signal intensities in central and peripheral portions of the joint were measured and compared between these two groups. In all cases, enhancement of joint fluid began at peripheral portion and progressed toward central portion. The diffusion rate in exercise group was far faster than that in nonexercise group and homogeneous arthrographic image was revealed within 10 minutes after completion of joint movement. The arthrographic effect continued and the rate of signal decrease was quite slow. MR arthrographic image of knee joint can be obtained within 10 minutes after completion of a few minute exercise following intravenous injection of gadopentetate dimeglumine. Intravenous MR arthrography is expected to become an useful method as a convenient alternative to direct MR arthrography.

  15. Arthrography

    Medline Plus

    Full Text Available ... you! Do you have a personal story about radiology? Share your patient story here Images × Image Gallery ... Magnetic Resonance Imaging (MRI) - Shoulder X-ray, Interventional Radiology and Nuclear Medicine Radiation Safety Images related to ...

  16. Arthrography

    Medline Plus

    Full Text Available ... side effects from the contrast material, including nausea, headache and pain at the site of injection. Similarly, ... have special pediatric considerations. The teddy bear denotes child-specific content. Related Articles and Media Magnetic Resonance ...

  17. Arthrography

    Medline Plus

    Full Text Available ... ankle arthrogram. View full size with caption Pediatric Content Some imaging tests and treatments have special pediatric considerations. The teddy bear denotes child-specific content. Related Articles and Media Magnetic Resonance Imaging (MRI) - ...

  18. Discrepancy between fluoroscopic arthrography and magnetic resonance arthrography in patients with arthroscopically confirmed supraspinatus tendon tears: The additional benefit of cine fluoroscopic arthrography images

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    Hahn, Seok; Lee, Young Han; Suh, Jin Suck [Dept. Radiology, Research Institute of Radiological Science, Medical Convergence Research Institute, and Severance Biomedical Science Institute, Yonsei University College of Medicine, Seoul (Korea, Republic of)

    2016-12-15

    To determine the additional diagnostic benefits of fluoroscopic arthrography (FA) in patients with full-thickness supraspinatus tendon (SST) tears by comparing FA images with magnetic resonance arthrography (MRA) images. This study included FA and MRA images of 53 patients who were confirmed to have full-thickness SST tears by arthroscopy. In the FA analysis, the presence of contrast leakage into the subacromial-subdeltoid bursa was recorded. In the MRA analysis, contrast leakage, retraction of a torn tendon, width and length of the tear, and supraspinatus atrophy were evaluated. Patients were divided into the concordant group or the discordant group based on the presence of contrast leakage to compare the characteristics of SST tears. We used Fisher's exact test and two-sample t-test for the comparison. Of the 53 patients, 34 were included in the concordant group and 19 were included in the discordant group. In the concordant group, the grades of retraction were higher than those in the discordant group; the width and length of the tears were larger. Muscle atrophy was more severe in the concordant group. A full-thickness SST tear did not always exhibit contrast leakage on FA, particularly small SST tears or tears with low-grade retraction. FA can provide diagnostic information regarding the severity of full-thickness SST tears by itself.

  19. Shoulder magnetic resonance arthrography in the sagittal oblique plane: pictorial essay

    Energy Technology Data Exchange (ETDEWEB)

    Andrews, G.; Forster, B.; Cheong, Y.; Sidhu, G. [Univ. of British Columbia, Dept. of Radiology, Vancouver, British Columbia (Canada); Hawkins, R.; Leith, J. [Univ. of British Columbia, Dept. of Orthopedics, Vancouver, British Columbia (Canada)

    2003-06-01

    Shoulder magnetic resonance (MR) arthrography is the imaging study of choice for investigating glenohumeral instability. The axial and coronal oblique planes have traditionally been used because it is on these planes that the glenoid labrum, as well as the biceps anchor and rotator cuff, are thought to be best evaluated. The purpose of this illustrative review is to demonstrate the diagnostic utility of the sagittal oblique plane in shoulder MR arthrography. Images identifying the normal and abnormal appearance of the labral, ligamentous, myotendinous and osteocartilaginous structures are presented, and comparisons to the axial and coronal oblique planes are made. (author)

  20. Ultrasound versus Magnetic Resonance Arthrography in Acetabular Labral Tear Diagnostics: A Prospective Comparison in 20 Dysplastic Hips

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    Troelsen, A.; Jacobsen, S.; Bolvig, L.; Gelineck, J.; Roemer, L.; Soeballe, K. [Orthopedic Research Unit and Dept. of Radiology, Univ. Hospital of Aarhus, A arhus (Denmark)

    2007-11-15

    Background: Acetabular labral tears are highly associated with hip dysplasia. Magnetic resonance arthrography (MR arthrography) is the expensive and time-consuming contemporary gold-standard method in the radiological assessment of acetabular labral tears. Purpose: To assess the diagnostic ability of noninvasive ultrasound (US) examination compared to MR arthrography in diagnosing acetabular labral tears in dysplastic hip joints. Material and Methods: The study compared US examination and MR arthrography diagnosis of labral tears in 20 consecutively referred dysplastic hip joints. Results: The ability to diagnose acetabular labral tears upon US examination was calculated: sensitivity 44%, specificity 75%, positive predictive value 88%, and negative predictive value 25%. Conclusion: The ability of US examination in diagnosing acetabular labral tears is not yet good enough. The technique is still to be developed, and more experience, especially with the interpretation of US examinations, is needed.

  1. Preoperative conventional magnetic resonance images versus magnetic resonance arthrography of subacromial impingement syndrome

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    Ahn, Sang Hyuk; Park, Jung Hwan; Moon, Tae Yong [Pusan National Univ. Yangsan Hospital, Yangsan (Korea, Republic of); Lee, In Sook; Lee, Seung Jun [Pusan National Univ. Hospital, Busan (Korea, Republic of)

    2012-09-15

    To evaluate the usefulness of conventional magnetic resonance images (MRI) for arthroscopic surgery in subacromial impingement syndrome of the shoulder, as an alternative to MR arthrography with additional T2 fat saturation images (MRA). The preoperative MRI of 77 patients (45 females, 32 males) (52 right, 25 left) and MRA of 34 patients (14 females, 20 males) (24 right, 10 left) with subsequent arthroscopic confirmation of subacromial impingement syndrome were reviewed retrospectively. The lesions requiring arthroscopic surgery were 95 subacromial spurs, 101 subacromial bursitis, and 51 full-thickness and 44 partial thickness tears of the supraspinatus among 111 cases for both studies. A two by two table was constructed in order to calculate the sensitivity and specificity of both studies against arthroscopic outcomes. Also we analyzed the false positive and false negative cases of the full-thickness tears individually. The detection rates of subacromial spur and bursitis and full and partial thickness tears of the supraspinatus were 91%, 94%, 77%, and 65% in MRI and 93%, 100%, 83%, and 77% in MRA respectively. Their specificities were 33%, 33%, 90%, and 76% in MRI and 50%, 75%, 100%, and 71% in MRA respectively. Eleven false negative cases in regards to MRI resulted in Ellman's grade 3 partial thickness tear (72.7%), mild bursitis (63.6%), greater tuberosity erosion (45.5%), and negative fluid signal of the glenohumeral joint (81.8%). Three false positive cases on the MRI were induced from errors with lower window depth and width on the imagings. Two false negative cases on MRA were induced from the adhesion between Ellman's grade 3 rim rent tear and the glenohumeral joint cavity. Conventional MR images could be used to decide the arthroscopic surgery in subacromial impingement syndrome, as an alternative to MR arthrography with additional T2 fat saturation images.

  2. Tears of the Supraspinatus Tendon: Assessment with Indirect Magnetic Resonance Arthrography in 67 Patients with Arthroscopic Correlation

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    Dyck, P. van; Gielen, J.L.; Parizel, P.M. (Dept. of Radiology, Univ. Hospital Antwerp and Univ. of Antwerp, Antwerp (Belgium)) (and others)

    2009-11-15

    Background: Magnetic resonance (MR) arthrography is generally regarded as the gold standard for shoulder imaging. As an alternative to direct MR arthrography, the less invasive indirect MR arthrography technique was proposed, offering logistic advantages because fluoroscopic or ultrasonographic guidance for joint injection is not required. Purpose: To assess the diagnostic performance of indirect MR arthrography in the diagnosis of full- and partial-thickness supraspinatus tears in a symptomatic population. Material and Methods: Two radiologists with different levels of experience independently and retrospectively interpreted indirect MR (1.5T) arthrograms of the shoulder obtained in 67 symptomatic patients who underwent subsequent arthroscopy. On MR, the supraspinatus tendon was evaluated for full- or partial-thickness tear. With arthroscopy as the standard of reference, sensitivity, specificity, and diagnostic accuracy of indirect MR arthrography in the detection of full- and partial-thickness tears of the supraspinatus tendon was calculated. Kappa (kappa) statistics were used for the assessment of the agreement between arthroscopic and imaging findings and for the assessment of interobserver agreement. Results: For full-thickness tears of the supraspinatus tendon, sensitivities, specificities, and accuracies exceeded 90% for both observers, with excellent interobserver agreement (kappa = 0.910). For partial-thickness tears, sensitivities (38-50%) and accuracies (76-78%) were poor for both reviewers, and interobserver agreement was moderate (kappa = 0.491). Discrepancies between MR diagnosis and arthroscopy were predominantly observed with small partial-thickness tears. Conclusion: Indirect MR arthrography is highly accurate in the diagnosis of full-thickness rotator cuff tears. However, the diagnosis of partial-thickness tears with indirect MR arthrography remains faulty, because exact demarcation of degenerative change and partial rupture is difficult. On the

  3. Fluoroscopically-Guided Posterior Approach for Shoulder Magnetic Resonance Arthrography: Comparison with Conventional Anterior Approach

    Energy Technology Data Exchange (ETDEWEB)

    Yoo, Koun J.; Ha, Doo Hoe; Lee, Sang Min [Dept. of Radiology, CHA Budang Medical Center, CHA University College of Medicine, Seongnam (Korea, Republic of)

    2011-10-15

    To prospectively evaluate the usefulness of the fluoroscopically-guided posterior approach compared with the anterior approach for shoulder magnetic resonance(MR) arthrography. Institutional review board approval and informed consent were obtained. Among 60 shoulder MR arthrographies performed on 59 patients with symptomatic shoulders, an intra-articular injection was performed (30 cases using the anterior approach and 30 using the posterior approach). Procedure-related pain was assessed by using a 5 score visual analogue scale (VAS). Depth of the puncture and standardized depth of puncture by body mass index (BMI) were recorded. The contrast leakage along the course of the puncture was evaluated by reviewing the MR. The statistical analyses included the Mann-Whitney U and Kruskal-Wallis test. There was no significant difference in VAS scores between the anterior and posterior groups (1.77 {+-} 1.10 vs. 1.80 {+-} 0.96). Depth of puncture and standardized depth of puncture by BMI were significantly shorter in the posterior group than those in the anterior group (4.4 {+-} 0.8 cm and 1.8 {+-} 0.3 cm vs. 6.6 {+-} 0.9 cm and 2.8 {+-} 0.4 cm, p < 0.001), respectively. The incidence of contrast leakage was more frequent in the posterior group (p = 0.003). The posterior approach will be useful in shoulder MR arthrography with a suspected anterior pathology, a postoperative follow-up study or obese patient.

  4. Validity of magnetic resonance arthrography as a diagnostic tool in femoroacetabular impingement syndrome.

    Science.gov (United States)

    González Gil, A B; Llombart Blanco, R; Díaz de Rada, P

    2015-01-01

    Femoroacetabular impingement (FAI) is one of the main causes of hip pain in young adult and a contributory factor for development of early primary osteoarthritis. An accurate clinical diagnosis, supported by imaging studies, is important to determine the best treatment for the patient. The aim of this study is to determine the diagnostic correlation between direct magnetic resonance imaging (MRI) arthrography and the arthroscopic findings. A review was performed on a series of 36 patients diagnosed with FAI, and who underwent hip arthroscopy surgery between 2009 and 2012. All of them had a direct MRI arthrography performed in our hospital. The presence of labral lesions, CAM deformity, and acetabular and femoral cartilage damage, were evaluated in both imaging techniques. After analysing the results and taking the hip arthroscopy as 'gold standard', a sensitivity of 87% and a specificity of 77% were obtained, with a PPV of 87% for the diagnosis of labral lesions by direct MR arthrography. The specificity for CAM deformity was 100%, with a sensitivity of 79% and PPV of 100%. For chondral disorders lower values were found for both acetabulum and femoral head. For acetabular lesions the sensitivity was 78.5%, and specificity was 82% with a PPV of 73% and NPV of 80%. For femoral lesions, there was a sensitivity of 71.5%, a specificity of 73%, with a PPV of 62.5% and NPV of 80%. Due to the high sensitivity for the detection of labral lesions and the high specificity to detect CAM deformity, hip MR arthrography is a useful diagnostic tool for femoroacetabular impingement. Copyright © 2014 SECOT. Published by Elsevier Espana. All rights reserved.

  5. The role of radiocarpal injection arthrography and magnetic resonance imaging in the diagnosis of triangular fibrocartilage complex injuries

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    Objective: To investigate the radiocarpal joint injectionarthrography and magnetic resonance imaging for diagnosis of the triangular fibrocartilage complex (TFCC) injuries.Methods: Thirteen cases whose main complaints were ulnar wrist pain were given radiocarpal joint arthrography and eight of them were also given magnetic resonance imaging for evaluating the integrity of the triangular fibrocartilage complex.Results: Ten of thirteen cases presented the leakage of contrast medium to distal radioulnar joint from the radiocarpal joint, in whom, 8 were demonstrated triangular fibrocartilage tear on magnetic resonance imaging, and 3 located at radial side, 2 at central, 3 at ulnar side. One of three cases which were demonstrated without the leakage of contrast medium in arthrography were displayed with marked TFCC tear on magnetic resonance imaging.Conclusions: The wrist arthrography can provide a definite diagnosis for triangular fibrocartilage disruption with higher sensitivity. magnetic resonance imaging not only demonstrates the site of triangular fibrocartilage disruption as the same value as wrist arthrography, but also displays the other related bony and soft tissues changes.

  6. Comparison of MDCTA (16-slice multi-detector row computed tomography arthrography) and MRA (magnetic resonance arthrography) for detecting labral lesions of the shoulder

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    Choi, Seung A; Cha, Jang Gyu; Hong, Hyun Sook; Choi, Deuk Lin; Park, Jai Soung; Lee, Hae Kyung; Kim, Dae Ho [Soonchunhyang University Bucheon Hospital, Bucheon (Korea, Republic of)

    2007-11-15

    To compare the accuracy of 16-slice multi-detector row computed tomographic arthrography (MDCTA) and magnetic resonance arthrography (MRA) for making the diagnosis and classification of labroligamentous injuries. This study is a prospective series that used MRA and MDCTA to examine 23 patients who complained of shoulder instability. Two radiologists independently analyzed the MRA and MDCTA. The sensitivity, specificity, accuracy, positive and negative predictive values were calculated from the arthrograms and the arthroscopic findings. The images of MDCTA and MRA corresponded with the findings on arthroscopy. Both imaging modalities had the same sensitivity for detecting Bankart lesions (n = 10, 90%) and posterior labral tears (n = 2, 50%) on McNemar test ({rho} = 1.00). For superior labrum anterior-to-posterior (SLAP) lesions, 6 MRA cases and 4 MDCTA cases corresponded with the arthroscopic findings. The difference between the sensitivities of MDCTA (66.7%) and MRA (100%) was not significant ({rho} 0.09). We suggest that the sensitivity of diagnosing labral lesions that induce shoulder instability is similar for MDCTA and MRA. MDCTA is effective for diagnosing and evaluating shoulder instability.

  7. Anatomy, variants, and pathologies of the superior glenohumeral ligament: Magnetic resonance imaging with three-dimensional volumetric interpolated breath-hold examination sequence and conventional magnetic resonance arthrography

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    Ogul, Hayri; Karaca, Leyla; Emre, Cahit; Pirimoglu, Berhan; Tuncer, Kutsi; Topai, Murat; Okur, Aylin; Kantarci, Mecit [Medical Faculty, Ataturk University, Erzurum (Turkmenistan)

    2014-08-15

    The purpose of this review was to demonstrate magnetic resonance (MR) arthrography findings of anatomy, variants, and pathologic conditions of the superior glenohumeral ligament (SGHL). This review also demonstrates the applicability of a new MR arthrography sequence in the anterosuperior portion of the glenohumeral joint. The SGHL is a very important anatomical structure in the rotator interval that is responsible for stabilizing the long head of the biceps tendon. Therefore, a torn SGHL can result in pain and instability. Observation of the SGHL is difficult when using conventional MR imaging, because the ligament may be poorly visualized. Shoulder MR arthrography is the most accurately established imaging technique for identifying pathologies of the SGHL and associated structures. The use of three dimensional (3D) volumetric interpolated breath-hold examination (VIBE) sequences produces thinner image slices and enables a higher in-plane resolution than conventional MR arthrography sequences. Therefore, shoulder MR arthrography using 3D VIBE sequences may contribute to evaluating of the smaller intraarticular structures such as the SGHL.

  8. Magnetic resonance arthrography in recurrent anterior shoulder instability as compared to arthroscopy: a prospective comparative study.

    Directory of Open Access Journals (Sweden)

    Parmar H

    2002-10-01

    Full Text Available AIM: To evaluate the accuracy of magnetic resonance (MR arthrographic imaging in the diagnosis of glenoid labral and ligament tears in recurrent shoulder instability. SETTINGS AND DESIGN: Prospective, comparative study at a tertiary care centre. MATERIAL AND METHODS: Patients with three or more episodes of anterior shoulder dislocation were enrolled in the study. They were subjected to magnetic resonance arthrography (MRA for delineation of abnormalities. The findings obtained at MRA were compared with those found at arthroscopy and surgical exploration. RESULTS: MRA detected glenoid tears in all 22 patients with 20 (90% patients having antero-inferior tears, 3 (14% patients had superior labral involvement and 2 (10% patients had posterior labral abnormality. On arthroscopy, antero-inferior, superior and posterior labral tear were found in 21 (95%, 5 (22% and 7 (32% patients respectively. MRA showed a sensitivity of 95%, and a specificity of 100% for the detection of the antero-inferior labral tears. The sensitivity of MRA for the detection of superior, middle and inferior glenohumeral ligament tear was 83%, 80% and 86% with a specificity of 100%, 71% and 93% respectively. MRA was 100% sensitive for the detection of rotator cuff injuries and detection of bony lesions like Hill-Sach′s and bony Bankart′s lesion. CONCLUSIONS: MRA is a sensitive and specific modality for evaluation of anterior shoulder instability.

  9. Shoulder Magnetic Resonance Arthrography: A Prospective Randomized Study of Anterior and Posterior Ultrasonography-Guided Contrast Injections

    Energy Technology Data Exchange (ETDEWEB)

    Koivikko, M.P.; Mustonen, A.O.T. (Dept. of Radiology, Helsinki Univ. Central Hospital, Helsinki (Finland))

    2008-10-15

    Background: Magnetic resonance (MR) arthrography is an accurate imaging method for internal shoulder derangements and rotator cuff pathologies. Both anterior and posterior contrast injection techniques, under palpatory, fluoroscopic, or ultrasonographic guidance have been described in the literature. However, clinical comparisons of the injection techniques remain few. Purpose: To compare the performance of anterior and posterior ultrasonography (US)-guided arthrography injections of the shoulder regarding patient discomfort and influence on diagnostic MR reading, and to illustrate the typical artifacts resulting from contrast leakage in the respective techniques. Material and Methods: 43 MR arthrographies were prospectively randomized into anterior and posterior US-guided contrast injections and performed by two radiologists, with the study of artifacts from contrast leakage. Pain from the injections was assessed by a survey utilizing a 100-mm visual analogue scale (VAS). Results: Of the 23 anterior injections, nine caused contrast artifacts in the subscapular tendon, and in three the leakage extended further anteriorly. Of the 20 posterior injections, 12 showed injection artifacts of the rotator cuff, extending outside the cuff in seven. Two of the anterior and none of the posterior artifacts compromised diagnostic quality. In posterior injections, the leakage regularly occurred at the caudal edge of the infraspinatus muscle and was easily distinguishable from rotator cuff tears. All patients completed the pain survey. Mean VAS scores were 25.0 (median 18, SD 22) for anterior, and 25.4 (median 16, SD 25) for posterior injections. The two radiologists achieved different mean VAS scores but closely agreed as to anterior and posterior VAS scores. Conclusion: Arthrography injections were fairly simple to perform under US guidance. Patient discomfort for anterior and posterior injections was equally minor. A tailored approach utilizing anterior or posterior injections

  10. A comparison of magnetic resonance arthrography and arthroscopic findings in the assessment of anterior shoulder dislocations

    Energy Technology Data Exchange (ETDEWEB)

    Jordan, R.W.; Naeem, R.; Srinivas, K.; Shyamalan, G. [Birmingham Heartlands Hospital, Birmingham (United Kingdom)

    2015-05-01

    The aim of this study is to establish the sensitivity and specificity of MRA in the investigation of patients with traumatic anterior shoulder dislocations. A retrospective analysis of consecutive patients undergoing both magnetic resonance arthrography and arthroscopic assessment after a traumatic anterior shoulder dislocation between January 2011 and 2014 was performed. Demographic data were collected from electronic records. Images were interpreted by 8 musculoskeletal radiologists and patients were treated by 8 consultant orthopaedic surgeons. Arthroscopic findings were obtained from surgical notes and these findings were used as a reference for MRA. The sensitivity, specificity, and positive predictive value were calculated for the different injuries. Sixty-nine patients underwent both an MRA and shoulder arthroscopy during the study period; however, clinical notes were unavailable in 9 patients. Fifty-three patients (88 %) were male, the mean age was 28 years (range 18 to 50) and 16 subjects (27 %) had suffered a primary dislocation. The overall sensitivity and specificity of MRA to all associated injuries was 0.9 (CI 0.83-0.95) and 0.94 (CI 0.9-0.96) retrospectively. The lowest sensitivity was seen in osseous Bankart 0.8 (CI 0.44-0.96) and superior labral tear (SLAP) lesions 0.5 (CI 0.14-0.86). The overall positive predictive value was 0.88 (CI 0.76-0.91) with the lowest values found in rotator cuff 0.4 (CI 0.07-0.83) and glenohumeral ligament (GHL) lesions 0.29 (CI 0.05-0.7). Magnetic resonance angiography has a high sensitivity when used to identify associated injuries in shoulder dislocation, although in 8 patients (13 %) arthroscopy identified an additional injury. The overall agreement between MRA and arthroscopic findings was good, but the identification of GHL and rotator cuff injuries was poor. (orig.)

  11. The Role of Wrist Magnetic Resonance Arthrography in Diagnosing Triangular Fibrocartilage Complex Tears; Experience at King Hussein Medical Center, Jordan

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    Asem A. Al-Hiari

    2013-05-01

    Full Text Available Objectives: The aims of the study were to evaluate the role of magnetic resonance arthrography (MRA of the wrist in detecting full-thickness tears of the triangular fibrocartilage complex (TFCC and to compare the results of the magnetic resonance arthrography (MRA with the gold standard arthroscopic findings. Methods:The study was performed at King Hussein Medical Center, Amman, Jordan, between January 2008 and December 2011. A total of 42 patients (35 males and 7 females who had ulnar-sided wrist pain and clinical suspicions of TFCC tears were included in the study. All patients underwent wrist magnetic resonance arthrography (MRA and then a wrist arthroscopy. The results of MRA were compared with the arthroscopic findings. Results: After comparison with the arthroscopic findings, the MRA had three false-negative results (sensitivity = 93% and no false-positive results. A total of 39 patients were able to return to work. Satisfaction was high in 38 of the patients and 33 had satisfactorypain relief. The sensitivity of the wrist MRA in detecting TFCC full-thickness tears was 93% (39, and specificity was 80% (16/20. The overall accuracy of wrist arthroscopy in detecting a full-thickness tear of the TFCC in our study was 85% (29/34. Conclusion: These results illustrate the role of wrist MRA in assessing the TFCC pathology and suggest its use as the first imaging technique, following a plain X-ray, in evaluating patients with chronic ulnar side wrist pain with suspected TFCC injuries.

  12. Magnetic resonance imaging arthrography of traumatic anterior instability of the shoulder

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    Miyazawa, Hiroshi [Showa Univ., Tokyo (Japan). School of Medicine

    2000-04-01

    Recently arthroscopic Bankart suture repair has been performed for the traumatic anterior instability of the shoulder. We investigated the use of MR arthrography in the diagnosis of anterior instability of the shoulder. The purpose of this study was to compare MR arthrography findings of an anterior inferior glenohumeral ligament-labrum complex with arthroscopic findings. Fifty shoulders with traumatic initial anterior dislocation and 50 shoulders with recurrent anterior dislocation and 10 shoulders of a control group without complaints were evaluated. Spin echo T1-weighted images in the transaxial plane and oblique coronal plane were obtained after injecting 20 ml of Gd-DTPA diluted with saline (1:100). Bankart lesion was evaluated by MR arthrography according to Hirose's classification (Type Na, Nb, 1a, 1b, 2, 3). There was a difference in the type of Bankart lesion between traumatic initial anterior dislocation and recurrent anterior dislocation. In the thickness of the anterior inferior glenohumeral ligament (AIGHL), there was a significant correlation between traumatic initial anterior dislocation and recurrent anterior dislocation (p<0.01) although the types of Bankart lesion were not related to the number of dislocation. Secondly, MR arthrography findings were compared with the Arthroscopic findings in 97 shoulders of 97 patients with recurrent shoulder dislocation. Arthroscopic findings were classified according to Kurokawa's classification (Type 1, 2n, 2a, 3n, 3a, 4a). MR arthrography findings of the Bankart lesion significantly correlated with the arthroscopic findings (p<0.01). MR arthrography clearly visualized AIGHL and was helpful in determining operative indications. (author)

  13. Diagnostic shortcomings of magnetic resonance arthrography to evaluate partial rotator cuff tears in adolescents.

    Science.gov (United States)

    Edmonds, Eric W; Eisner, Eric A; Kruk, Peter G; Roocroft, Joanna H; Dwek, Jerry D

    2015-06-01

    Recent evidence suggests an increase in the incidence of partial articular-sided rotator cuff tears in adolescent athletes, but the accuracy of diagnostic studies has not been previously assessed in this cohort. This study was performed to assess the ability of magnetic resonance imaging with arthrography (MRIa) to diagnose partial rotator cuff (PRC) pathology in the adolescent age group. All patients under the age of 19 years who underwent shoulder arthroscopy, between August 2008 and August 2010, were grouped based on the presence of a PRC tear diagnosed by either MRIa or arthroscopy. The control cohort included children without evidence of an intraoperative PRC. Surgical findings were then correlated with the preoperative MRIa findings and the accuracy of MRIa reading. Interclass coefficient was then determined for the MRIa reviewers. Thirty-one of 89 adolescents (mean age, 15.9 y; 36% girls and 64% boys) who underwent arthroscopic shoulder surgery were found to have radiographic or arthroscopic evidence of a PRC injury. There were 17 boys and 14 girls in the PRC group, with a mean age of 15.6 years. The PRC injuries involved either the supraspinatus tendon, infraspinatus tendon, or both. MRIa was 44% sensitive and 87% specific, with a positive predictive value of 64% and a negative predictive value of 74% with arthroscopic findings used as the gold standard. The ICC between reviewers was κ=0.57, with an absolute agreement of 84%. The overall diagnostic accuracy of the MRIa with regard to adolescent PRC injuries was 72%. MRIa was found to be specific, but not sensitive for the diagnosis of this pathology. The high false-negative rate seen in this adolescent cohort indicates that a PRC injury may be present even with a negative MRIa. Therefore, if clinical suspicion indicates a PRC injury, then the treating physician should consider management for rotator cuff pathology despite negative MRIa findings. Level III--retrospective cohort study.

  14. Effects of iodinated contrast agent, xylocaine and gadolinium concentration on the signal emitted in magnetic resonance arthrography: a samples study

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    Yvana Lopes Pinheiro da Silva

    2015-04-01

    Full Text Available Objective: To investigate the effects of dilution of paramagnetic contrast agent with iodinated contrast and xylocaine on the signal intensity during magnetic resonance arthrography, and to improve the paramagnetic contrast agent concentration utilized in this imaging modality. Materials and Methods: Samples specially prepared for the study with three different concentrations of paramagnetic contrast agent diluted in saline, iodinated contrast agent and xylocaine were imaged with fast spin echo T1-weighted sequences with fat saturation. The samples were placed into flasks and graphical analysis of the signal intensity was performed as a function of the paramagnetic contrast concentration. Results: As compared with samples of equal concentrations diluted only with saline, the authors have observed an average signal intensity decrease of 20.67% for iodinated contrast agent, and of 28.34% for xylocaine. However, the increased gadolinium concentration in the samples caused decrease in signal intensity with all the dilutions. Conclusion: Minimizing the use of iodinated contrast media and xylocaine and/or the use of a gadolinium concentration of 2.5 mmol/L diluted in saline will improve the sensitivity of magnetic resonance arthrography.

  15. Magnetic resonance arthrography in chronic wrist pain. Artografia con Risonanza Magnetica (arto-RM) nelle malattie dolorose croniche del polso

    Energy Technology Data Exchange (ETDEWEB)

    Valeri, G.; Ferrara, C. (Ancona Univ. (Italy). Cattedra di Radiologia); Carloni, S. (Ancona Univ. (Italy). Cattedra di Ortopedia) (and others)

    The purpose of this paper is to investigate the clinical role of Magnetic Resonance Arthrography (MRA) of the wrist in subjects with chronic pain. Thirty-five patients complaining of wrist pain for more than 6 months were submitted to MRI an MRA. All patients received and intra-articular injection of 2-10 mL of a 10 mmol saline solution of Gd-DPTA. The overall diagnostic accuracy rates of MRI and MRA were 40% and 81% respectively, with sensitivity and specificity of 63% and 39% (MRI) and of 82% and 79% (MRA). The conclusion is that compared with MRI, MRA can be considered a useful tool for the visualization of interosseus carpal ligaments and of the triangular fibrocartilage complex. MRA also helps detect injuries in these structures.

  16. Evaluation of lesions of the internal ligaments of the wrist; conventional magnetic resonance imaging versus MR arthrography (MRA

    Directory of Open Access Journals (Sweden)

    Heba Ahmed Kamal

    2014-09-01

    Conclusion: MR arthrography is a potent additional tool facilitating the diagnosis of different pathologic entities affecting the major internal ligaments of the wrist joint and helps to reduce arthroscopic interventions.

  17. Magnetic resonance arthrography including ABER view in diagnosing partial-thickness tears of the rotator cuff: Accuracy, and inter- and intra-observer agreements

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    Jung, Joon-Yong; Jee, Won-Hee; Chun, Ho Jong; Ahn, Myeong Im (Dept. of Radiology, Seoul St. Mary' s Hospital, School of Medicine, Catholic Univ. of Korea, Seoul (Korea)), e-mail: whjee@catholic.ac.kr; Kim, Yang-Soo (Dept. of Orthopedic Surgery, Seoul St. Mary' s Hospital, School of Medicine, Catholic Univ. of Korea, Seoul (Korea))

    2010-03-15

    Background: Partial-thickness tear of the rotator cuff is a common cause of shoulder pain. Magnetic resonance (MR) arthrography has been described as a useful measure to diagnose rotator cuff abnormalities. Purpose: To determine the reliability and accuracy of MR arthrography with abduction and external rotation (ABER) view for the diagnosis of partial-thickness tears of the rotator cuff. Material and Methods: Among patients who underwent MR arthrographies, 22 patients (12 men, 10 women; mean age 45 years) who had either partial-thickness tear or normal tendon on arthroscopy were included. MR images were independently scored by two observers for partial-thickness tears of the rotator cuff. Interobserver and intraobserver agreements for detection of partial-thickness tears of the rotator cuff were calculated by using kappa coefficients. The differences in areas under the receiver operating characteristic (ROC) curves were assessed with a univariate Z-score test. Differences in sensitivity and specificity for interpretations based on different imaging series were tested for significance using the McNemar statistic. Results: Sensitivity, specificity, and accuracy of each reader on MR imaging without ABER view were 83%, 90%, and 86%, and 83%, 80%, and 82%, respectively, whereas on overall interpretation including ABER view, the sensitivity, specificity, and accuracy of each reader were 92%, 70%, and 82%, and 92%, 80%, and 86%, respectively. Including ABER view, interobserver agreement for partial-thickness tear increased from kappa=0.55 to kappa=0.68. Likewise, intraobserver agreements increased from kappa=0.79 and 0.53 to kappa=0.81 and 0.70 for each reader, respectively. The areas under the ROC curves for each reader were 0.96 and 0.90, which were not significantly different. Conclusion: Including ABER view in routine sequences of MR arthrography increases the sensitivity, and inter- and intraobserver agreements for detecting partial-thickness tear of rotator cuff

  18. The diagnostic value of magnetic resonance arthrography of the shoulder in detection and grading of SLAP lesions: Comparison with arthroscopic findings

    Energy Technology Data Exchange (ETDEWEB)

    Amin, Mohammed Farghally, E-mail: Mohammed_amin37@yahoo.com [Department of Radiodiagnosis ElMinya University, ElMinya High Road, ElMinya (Egypt); Youssef, Ahmed Omar [Department of Orthropedic Surgery El Minya University, ElMinya (Egypt)

    2012-09-15

    Purpose: The purpose of the study is to determine the usefulness of magnetic resonance arthrography (MRA) in diagnosis and grading of superior labrum anterior to posterior (SLAP) lesions of the Glenoid Labrum Compared with surgery Material and methods: This was a prospective study including fifty nine clinically diagnosed SLAP patients. The study was done during the period from January 2008 to June 2010. All patients were submitted to history taking, clinical examination and conventional MRI examination of the shoulder, MRA was done in patients with negative conventional MRI, all of these patients underwent arthroscopy for diagnosis wither open or arthroscopy for diagnosis and treatment and results were compared with MRA findings. Main outcome measures: Sensitivity, specificity, positive and negative predictive values, and overall accuracy of MR arthrography in detection and grading of SLAP lesions of the gelnoid labrum. Results: Out of fifty nine patients, 25 patients had positive MR findings in conventional MRI, and 34 patients had negative MR findings, who underwent MR arthrography; 10 out of them had normal arthrogram (only 6 of them underwent arthroscopy), 22 had SLAP (superior labrum anterior to posterior) lesions, one had Bankart's lesion and one had internal impingement syndrome. These results were compared with arthroscopy results. The overall sensitivity of MRA in detection of SLAP lesions was 90% while the specificity was 50%, negative predictive value (NPV) was 66.6% and positive predicative value (PPV) was 81.8%. MRA and arthroscopy results were concurrent in 79.3% patients. Conclusion: MR arthrography is a sensitive minimally invasive technique for detection and grading of SLAP lesions, it can help in avoiding patients unnecessary diagnostic arthroscopy.

  19. Magnetic resonance imaging and magnetic resonance arthrography of the shoulder: dependence on the level of training of the performing radiologist for diagnostic accuracy

    Energy Technology Data Exchange (ETDEWEB)

    Theodoropoulos, John S. [University of Toronto, Division of Orthopaedics, Mount Sinai Hospital and the University Health Network, Toronto, ON (Canada); Andreisek, Gustav [University of Toronto, Department of Medical Imaging, Mount Sinai Hospital and the University Health Network, Toronto, ON (Canada); University Hospital Zuerich, Institute for Diagnostic Radiology, Zuerich (Switzerland); Harvey, Edward J. [McGill University, Division of Orthopaedics, MUHC - Montreal General Hospital, Montreal, Quebec (Canada); Wolin, Preston [Center for Athletic Medicine, Chicago, IL (United States)

    2010-07-15

    Discrepancies were identified between magnetic resonance (MR) imaging and clinical findings in patients who had MR imaging examinations evaluated by community-based general radiologists. The purpose of this study was to evaluate the diagnostic performance of MR imaging examinations of the shoulder with regard to the training level of the performing radiologist. A review of patient charts identified 238 patients (male/female, 175/63; mean age, 40.4 years) in whom 250 arthroscopies were performed and who underwent MR imaging or direct MR arthrography in either a community-based or hospital-based institution prior to surgery. All MR imaging and surgical reports were reviewed and the diagnostic performance for the detection of labral, rotator cuff, biceps, and Hill-Sachs lesions was determined. Kappa and Student's t test analyses were performed in a subset of cases in which initial community-based MR images were re-evaluated by hospital-based musculoskeletal radiologists, to determine the interobserver agreement and any differences in image interpretation. The diagnostic performance of community-based general radiologists was lower than that of hospital-based sub-specialized musculoskeletal radiologists. A sub-analysis of re-evaluated cases showed that musculoskeletal radiologists performed better. {kappa} values were 0.208, 0.396, 0.376, and 0.788 for labral, rotator cuff, biceps, and Hill-Sachs lesions (t test statistics: p =<0.001, 0.004, 0.019, and 0.235). Our results indicate that the diagnostic performance of MR imaging and MR arthrography of the shoulder depends on the training level of the performing radiologist, with sub-specialized musculoskeletal radiologists having a better diagnostic performance than general radiologists. (orig.)

  20. Texture analysis of torn rotator cuff on preoperative magnetic resonance arthrography as a predictor of postoperative tendon status

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    Kang, Yeon Ah; Lee, Guen Young; Lee, Joon Woo; Lee, Eugene; Kim, Boh Young; Kim, Su Jin; Ahn, Joong Mo; Kang, Heung Sik [Dept. of Radiology, Seoul National University Bundang Hospital, Seongnam (Korea, Republic of)

    2017-08-01

    To evaluate texture data of the torn supraspinatus tendon (SST) on preoperative T2-weighted magnetic resonance arthrography (MRA) using the gray-level co-occurrence matrix (GLCM) for prediction of post-operative tendon state. Fifty patients who underwent arthroscopic rotator cuff repair for full-thickness tears of the SST were included in this retrospective study. Based on 1-year follow-up, magnetic resonance imaging showed that 30 patients had intact SSTs, and 20 had rotator cuff retears. Using GLCM, two radiologists measured independently the highest signal intensity area of the distal end of the torn SST on preoperative T2-weighted MRA, which were compared between two groups.The relationships with other well-known prognostic factors, including age, tear size (anteroposterior dimension), retraction size (mediolateral tear length), grade of fatty degeneration of the SST and infraspinatus tendon, and arthroscopic fixation technique (single or double row), also were evaluated. Of all the GLCM features, the retear group showed significantly higher entropy (p < 0.001 and p = 0.001), variance (p = 0.030 and 0.011), and contrast (p = 0.033 and 0.012), but lower angular second moment (p < 0.001 and p = 0.002) and inverse difference moment (p = 0.027 and 0.027), as well as larger tear size (p = 0.001) and retraction size (p = 0.002) than the intact group. Retraction size (odds ratio [OR] = 3.053) and entropy (OR = 17.095) were significant predictors. Texture analysis of torn SSTs on preoperative T2-weighted MRA using the GLCM may be helpful to predict postoperative tendon state after rotator cuff repair.

  1. Ultrasound guidance to perform intra-articular injection of gadolinium-based contrast material for magnetic resonance arthrography as an alternative to fluoroscopy: the time is now

    Energy Technology Data Exchange (ETDEWEB)

    Messina, Carmelo [Universita degli Studi di Milano, Scuola di Specializzazione in Radiodiagnostica, Milano (Italy); Banfi, Giuseppe [IRCCS Istituto Ortopedico Galeazzi, Milano (Italy); Universita Vita-Salute San Raffaele, Milano (Italy); Aliprandi, Alberto [Universita degli Studi di Milano, Dipartimento di Scienze Biomediche per la Salute, Milano (Italy); Mauri, Giovanni [Universita degli Studi di Milano, Dipartimento di Scienze Biomediche per la Salute, Milano (Italy); Istituto Europeo di Oncologia, Unita di Radiologia Interventistica, Milano (Italy); Secchi, Francesco; Sardanelli, Francesco; Sconfienza, Luca Maria [Universita degli Studi di Milano, Dipartimento di Scienze Biomediche per la Salute, Milano (Italy); IRCCS Policlinico San Donato, Servizio di Radiologia, San Donato, Milanese (Italy)

    2016-05-15

    Magnetic resonance (MR) imaging has been definitively established as the reference standard in the evaluation of joints in the body. Similarly, magnetic resonance arthrography has emerged as a technique that has been proven to increase significantly the diagnostic performance if compared with conventional MR imaging, especially when dealing with fibrocartilage and articular cartilage abnormalities. Diluted gadolinium can be injected in the joint space using different approaches: under palpation using anatomic landmarks or using an imaging guidance, such as fluoroscopy, computed tomography, or ultrasound. Fluoroscopy has been traditionally used, but the involvement of ionizing radiation should represent a remarkable limitation of this modality. Conversely, ultrasound has emerged as a feasible, cheap, quick, and radiation-free modality that can be used to inject joints, with comparable accuracy of fluoroscopy. In the present paper, we discuss the advantages and disadvantages of using fluoroscopy or ultrasound in injecting gadolinium-based contrast agents in joints to perform magnetic resonance arthrography, also in view of the new EuroSAFE Imaging initiative promoted by the European Society of Radiology and the recent updates to the European Atomic Energy Community 2013/59 directive on the medical use of ionizing radiation. (orig.)

  2. Magnetic resonance arthrography of the shoulder: accuracy of gadolinium versus saline for rotator cuff and labral pathology

    Energy Technology Data Exchange (ETDEWEB)

    Helms, Clyde A.; McGonegle, Shane J.; Vinson, Emily N.; Whiteside, Michael B. [Duke University Medical Center, Department of Radiology, Durham, NC (United States)

    2011-02-15

    The purpose of this study was to evaluate the necessity of intra-articular gadolinium versus saline alone in magnetic resonance arthrography (MRA) of the shoulder. Our database was reviewed for 100 consecutive shoulder MRA examinations performed between January 2007 and December 2007. Patient information was blinded and images were retrospectively reviewed by at least two radiologists with dedicated musculoskeletal training. T2-weighted (T2W) images were initially analyzed in isolation to simulate MRA with saline alone. After a delay, the full study was analyzed including T1-weighted (T1W) and T2W images. If there was a significant discordance between the two analyses with regard to rotator cuff or labral pathology, the study was again reviewed by all evaluators in consensus to determine if the T1W images offered additional diagnostic information and increased diagnostic confidence. Of the 100 MRA examinations, there were 15 discordant cases. Two cases were discordant with regard to rotator cuff pathology and 13 were discordant on the basis of labral pathology. When the discordant cases were reviewed in consensus, the T2W images appeared to display rotator cuff and labral pathology as definitively as the T1W images. Interobserver and intraobserver variability was favored to have played a role in causing the discordances. MRA of the shoulder performed with joint distention provided by saline alone appears to offer equivalent diagnostic information to MRA performed with gadolinium enhancement. This protocol modification improves efficiency by eliminating several image series and provides a small cost savings by eliminating gadolinium. (orig.)

  3. Indirect magnetic resonance arthrography of the shoulder; a reliable diagnostic tool for investigation of suspected labral pathology

    Energy Technology Data Exchange (ETDEWEB)

    Fallahi, Farshid [North Cumbria University Hospitals NHS Trust, Carlisle (United Kingdom); North Cumbria University Hospitals, Department of Radiology, Carlisle (United Kingdom); Green, Nick; Gadde, Sarat; Jeavons, Lisa; Armstrong, Patrick; Jonker, Leon [North Cumbria University Hospitals NHS Trust, Carlisle (United Kingdom)

    2013-09-15

    Indirect magnetic resonance arthrography (I-MRA) confers significant logistical advantages over direct MRA and does not require articular injection. In this study, we determined the diagnostic performance of I-MRA in relation to conventional MRI and arthroscopy or surgery in detecting tears of the glenoid labrum, including Bankart lesions and superior labral antero-posterior (SLAP) tears in a standard clinical setting. Ninety-one symptomatic patients underwent conventional MRI and I-MRA of the affected shoulder, followed by either arthroscopy or open surgery. The scans were interpreted independently by two experienced radiology consultants with a special interest in musculoskeletal radiology. Using the surgical findings as the standard of reference, sensitivity, specificity, and diagnostic accuracy of conventional non-contrast MRI and I-MRA in the detection of labral tears were calculated. The sensitivity of I-MRA was 95 and 97 %, respectively, for two radiologists as opposed to 79 and 83 % for conventional MRI. For both radiologists, the specificity of I-MRA, as well as MRI, was 91 % for detection of labral tears of all types. Accuracy of diagnosis was 93 and 95 %, respectively, for two radiologists with indirect MRA, compared to 84 and 86 % with non-contrast MRI. This retrospective study shows that I-MRA is a highly accurate and sensitive method for the detection of labral tears. The data obtained supports the use of I-MRA as standard practice in patients with shoulder instability due to suspected labral pathology where further investigative imaging is indicated. (orig.)

  4. Retears of postoperative knee meniscus: findings on magnetic resonance imaging (MRI) and magnetic resonance arthrography (MRA) by using low and high field magnets

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    Cardello, Paolo; Pofi, Enrico [Belcolle Hospital, Department of Radiodiagnostic, Viterbo (Italy); Gigli, Carlo; Voglino, Nicola [Belcolle Hospital, Division of Knee Surgery and Arthroscopy, Department of Orthopedics and Traumatology, Viterbo (Italy); Ricci, Alessandra; Chiatti, Leonardo [Belcolle Hospital, Department of Medical Physics, Viterbo (Italy)

    2009-02-15

    The purpose of this study was to determine the diagnostic performance of magnetic resonance (MR) obtained with intra-articular contrast medium in the evaluation of recurrent meniscal tears using low-field extremity-only and high-field whole-body magnets. Postoperative standard MR examinations and MR arthrographies of 95 knees were reviewed. Patients experiencing pain and disability after meniscal repair underwent standard MR and MR arthrography (Gadoterate meglumine 0.0025 mmol/ml) on both a 0.2-T and 1.5-T magnet. In 52 of 95 patients, second-look arthroscopy was performed; in the remaining 43 of 95 patients, clinical follow-up was used as the standard of reference. Sensitivity, specificity, positive and negative predictive values as well as accuracy of MRI/MR arthrographic signs as meniscal morphologic changes and the presence of contrast medium tracking into the tear at T1- and T2-weighted sequences in the detection of recurrent meniscal tears were determined. All MR and MR arthrograpic signs were sensitive in the detection of recurrent tears (range 80-91%). Abnormal meniscal morphology had low specificity [26% (13/50)] for both the 0.2-T and 1.5-T scanner, whereas accuracy was 55% (52/95) and 57% (54/95), respectively. The presence of contrast medium within the meniscus substance on T2-weighted images had higher value of specificity [84% (42/50)] and accuracy [84% (80/95)] by using low field strength magnet than by using high field strength magnet [74% (37/50) and 81% (77/95), respectively]. Whereas, the increased intrameniscal signal intensity extending to the meniscal surface at T1-weighted sequences after intra-articular contrast medium administration had lower specificity and accuracy on 0.2-T images [84% (42/50) and 82% (78/95), respectively] than on 1.5-T images [90% (45/50) and 88% (84/95), respectively]. A diagnosis of recurrent meniscal tear in a previously arthroscopically repaired meniscus can be made both on 0.2-T and 1.5-T magnets on the basis of

  5. Magnetic resonance imaging arthrography following type II superior labrum from anterior to posterior repair: interobserver and intraobserver reliability

    Directory of Open Access Journals (Sweden)

    Kurji HM

    2015-11-01

    Full Text Available Hafeez M Kurji,1 Yohei Ono,2,3 Atiba A Nelson,2 Kristie D More,2 Ben Wong,4 Corinne Dyke,4 Richard S Boorman,2 Gail M Thornton,2,5 Ian KY Lo2 1College of Medicine, University of Saskatchewan, Saskatoon, SK, Canada; 2Department of Surgery, Section of Orthopaedic Surgery, McCaig Institute for Bone and Joint Health, University of Calgary, Calgary, AB, Canada; 3Department of Orthopedic Surgery, Nagoya University Graduate School of Medicine, Nagoya, Japan; 4Department of Radiology, University of Calgary, Calgary, AB, Canada; 5Department of Orthopaedics, University of British Columbia, Vancouver, BC, Canada Background: Arthroscopic repair of type II superior labrum from anterior to posterior (SLAP lesions is a common surgical procedure. However, anatomic healing following repair has rarely been investigated. The intraobserver and interobserver reliability of magnetic resonance imaging arthrography (MRA following type II SLAP repair has not previously been investigated. This is of particular interest due to recent reports of poor clinical results following type II SLAP lesion repair. Purpose: To evaluate the MRA findings following arthroscopic type II SLAP lesion repair and determine its intraobserver and interobserver reliability. Study design: Cohort study (diagnosis, Level of Evidence, 2. Methods: Twenty-five patients with an isolated type II SLAP lesion (confirmed via diagnostic arthroscopy underwent standard suture anchor-based repair. At a mean of 25.2 months postoperatively, patients underwent a standardized MRA protocol to investigate the integrity of the repair. MRAs were independently reviewed by two radiologists and a fellowship trained shoulder surgeon. The outcomes were classified as healed SLAP repair or re-torn SLAP repair. Results: On average, 54% of MRAs were interpreted as healed SLAP repairs while 46% of MRAs were interpreted as having a re-torn SLAP repair. Overall, only 43% of the studies had 100% agreement across all

  6. Is a single direct MR arthrography series in ABER position as accurate in detecting anteroinferior labroligamentous lesions as conventional MR arthography?

    NARCIS (Netherlands)

    Schreinemachers, S.A.; van der Hulst, V.P.M.; Willems, W.J.; Bipat, S.; van der Woude, H.J.

    2009-01-01

    The purpose of this study is to retrospectively compare accuracy of single magnetic resonance (MR) arthrography series in Abduction External Rotation (ABER) with conventional MR arthrography for detection and characterisation of anteroinferior labroligamentous lesions, with arthroscopy as reference

  7. PT -symmetric spectral singularity and negative-frequency resonance

    Science.gov (United States)

    Pendharker, Sarang; Guo, Yu; Khosravi, Farhad; Jacob, Zubin

    2017-03-01

    Vacuum consists of a bath of balanced and symmetric positive- and negative-frequency fluctuations. Media in relative motion or accelerated observers can break this symmetry and preferentially amplify negative-frequency modes as in quantum Cherenkov radiation and Unruh radiation. Here, we show the existence of a universal negative-frequency-momentum mirror symmetry in the relativistic Lorentzian transformation for electromagnetic waves. We show the connection of our discovered symmetry to parity-time (PT ) symmetry in moving media and the resulting spectral singularity in vacuum fluctuation-related effects. We prove that this spectral singularity can occur in the case of two metallic plates in relative motion interacting through positive- and negative-frequency plasmonic fluctuations (negative-frequency resonance). Our work paves the way for understanding the role of PT -symmetric spectral singularities in amplifying fluctuations and motivates the search for PT symmetry in novel photonic systems.

  8. Study on hip magnetic resonance arthrography and scan technology%髋关节磁共振造影及扫描技术的研究

    Institute of Scientific and Technical Information of China (English)

    郁冰冰; 丁娟; 朱明; 李杰; 姜庆军

    2011-01-01

    Objective To investigate the technology of the hip joint puncture and to optimize the protocol of magnetic resonance ( MR) arthrography scan sequences . Methods Twenty patients complaint hip pain ,who were confirmed no femoral head necrosis by MRI , were received fluoroscope -guided injection of the contrast media into the hip joint ( hip arthrography ) . Four kinds of sequences including fat -saturated spin-echo T2WI,fat-saturated spin-echo T1WI, proton dense weighted and 3D T1WI-FSPGR were used to scan separately. According to whether acetahular labral and its tears were displayed clearly , all the images were scored blindly. Results All of patients undergone the puncture of hip joints were successful . In all sequences ,T1WI sequence can better showed the acetabular labral and its tears ; PDWI sequence was took advantage to show cartilage abnormalities signals ; T2WI sequence were the best in the display of bone marrow abnormalities signals. Conclusions The fluoroscope-guided hip injection is convenient and safe . Optimization of MRI sequences include the followings : ( 1 ) oblique axial paralleled to the femur neck ( T1WI fat-saturated spin-echo) . ( 2) oblique coronal perpendicular to the acetabular line ( PDWI fat-saturated spinecho ) . ( 3 ) oblique axial paralleled to the femur neck ( T1WI-FSPGR spin -echo ) . Fat-saturated spin -echo T2 weighted sequence is needed if there is no conventional MR scanning .%目的 探讨髋关节MR造影穿刺技术及优化扫描方案.方法 临床髋部疼痛,常规MRI检查除外股骨头坏死的患者20例,共21个髋关节在透视下进行髋关节造影;分别采用T2WI、T1WI、PDWI、3D-T1WI-FSPGR四种序列进行扫描,将所有图像根据髋臼唇及撕裂显示是否清晰,软骨、骨髓异常信号显示是否清晰进行盲法评分,并进行统计分析.结果 透视下髋关节穿刺成功率100%(21/21).T1WI序列在显示髋臼唇及撕裂方面占有优势,PDWI序列在显示软骨异

  9. Localization, quantum resonances, and ratchet acceleration in a periodically kicked PT -symmetric quantum rotator

    Science.gov (United States)

    Longhi, Stefano

    2017-01-01

    We consider wave transport phenomena in a PT -symmetric extension of the periodically kicked quantum rotator model and reveal that dynamical localization assists the unbroken PT phase. In the delocalized (quantum resonance) regime, PT symmetry is always in the broken phase and ratchet acceleration arises as a signature of unidirectional non-Hermitian transport. An optical implementation of the periodically kicked PT -symmetric Hamiltonian, based on transverse beam propagation in a passive optical resonator with combined phase and loss gratings, is suggested to visualize acceleration modes in fractional Talbot cavities.

  10. Shape resonances and EXAFS scattering in the $Pt L_{2,3}$ XANES from a Pt electrode

    CERN Document Server

    O'Grady, W E

    1999-01-01

    Atomic hydrogen and oxygen adsorption on a platinum electrode in H /sub 2/SO/sub 4/ and HClO/sub 4/ electrolytes were studied by Pt L /sub 23/ XANES. The Pt electrode was formed of highly dispersed 1.5-3.0 nm particles supported on $9 carbon. A difference procedure utilizing the L/sub 2/ and L/sub 3/ spectra at various applied voltages was used to isolate the electronic and geometric effects in the XANES spectra. At 0.54 V (relative to RHE) the Pt electrode in $9 HClO/sub 4/ is assumed to be "clean". By taking the difference between the spectra at 0.0 and 0.54 V, the Pt-H antibonding state (electronic effect) is isolated and found to have a Fano-resonance line shape. In addition, a $9 significant Pt-H EXAFS scattering (geometric effect) was found for photon energies 0 to 20 eV above the edge. The difference between the spectra at 1.14 and 0.54 V allows isolation of the Pt-O antibonding state and the Pt-O EXAFS $9 scattering. (7 refs).

  11. Magnetic resonance arthrography assessment of the superior labrum using the BLC system: age-related changes mimicking SLAP-2 lesions

    Energy Technology Data Exchange (ETDEWEB)

    Koziak, Adrian [Queen' s School of Medicine, Kingston, Ontario (Canada); Chuang, Michael J.; Jancosko, Jason J.; Nottage, Wesley M. [The Sport Clinic Orthopedic Medical Associates, Inc., Laguna Hills, CA (United States); Burnett, Keith R. [Saddleback Valley Radiology, Laguna Hills, CA (United States)

    2014-08-15

    The purpose of the study was to describe the variation of the superior labrum with increasing age by assessing magnetic resonance (MR) arthrograms. Inclusion criteria were used to include only the MR arthrograms of patients devoid of clinical labral pathology. Two hundred thiry-six MR arthrograms were blindly assessed for biceps-labral complex (BLC) type 1-3 and sublabral recess size by a musculoskeletal radiologist. We have chosen the BLC system, which defines normal superior labral variants, since it is established in the literature and is used by reporting musculoskeletal (MSK) radiologists. The MR arthrograms demonstrated that the majority of patients <40 years old were BLC type 1 and showed a steady increase in BLC types 2 and 3 with increasing age. Assessments demonstrated significantly greater (p < 0.01) mean BLC types (1.62 vs 1.29) and recess size (1.35 vs 0.66 mm) in those over 40 compared with those less than 40 years of age. Furthermore, significant differences (p < 0.05) were noted between mean BLC assessments between different decades of age. There appears to be a physiologic deepening of the superior labrum sulcus with age, which becomes significant after the age of 40. These findings can contribute to whether the superior labrum is considered abnormal when assessed radiographically. The differentiation of normal age-related changes in the shoulder, from those of a type 2 SLAP tear can reduce the rates of unnecessary SLAP-2 repairs. This is the first reported series to use the BLC system; we believe it provides a common nomenclature to allow clear communication between specialists. (orig.)

  12. Perpendicular Magnetic Anisotropy and Induced Magnetic Structures of Pt Layers in the Fe/Pt Multilayers Investigated by Resonant X-ray Magnetic Scattering

    Science.gov (United States)

    Lee, Mihee; Takechi, Ryota; Hosoito, Nobuyoshi

    2017-02-01

    Depth distribution of the magnetization induced in the paramagnetic Pt layers of Fe/Pt multilayers was investigated by resonant X-ray magnetic scattering (RXMS) near the Pt L3 absorption edge. Two samples with different perpendicular magnetic anisotropy (PMA) were chosen for RXMS measurements. The magnetic depth profile of the Pt layer was determined in the magnetic saturation state of the Fe magnetization with the sample of weak PMA. The magnetization process of the Pt layer was investigated with the sample of moderate PMA. It is found that the Pt atoms near the interface region have a perpendicular component of the induced magnetization even in the saturation state of the Fe magnetization, suggesting that the PMA of Fe/Pt multilayers originates from the Pt atoms near the interface region. Concerning the magnetization process, the induced Pt magnetization is not proportional to the Fe magnetization. This implies a complicated magnetizing mechanism of the Pt layer by the Fe magnetization.

  13. Wrist arthrography: a simple method

    Energy Technology Data Exchange (ETDEWEB)

    Berna-Serna, Juan D.; Reus, Manuel; Alonso, Jose [Virgen de la Arrixaca University Hospital, Department of Radiology, El Palmar (Murcia) (Spain); Martinez, Francisco; Domenech-Ratto, Gines [University of Murcia, Department of Human Anatomy, Faculty of Medicine, Murcia (Spain)

    2006-02-01

    A technique of wrist arthrography is presented using an adhesive marker-plate with radiopaque coordinates to identify precisely sites for puncture arthrography of the wrist and to obviate the need for fluoroscopic guidance. Radiocarpal joint arthrography was performed successfully in all 24 cases, 14 in the cadaveric wrists and 10 in the live patients. The arthrographic procedure described in this study is simple, safe, and rapid, and has the advantage of precise localisation of the site for puncture without need for fluoroscopic guidance. (orig.)

  14. Diagnosis of lesions of the acetabular labrum, of the labral-chondral transition zone, and of the cartilage in femoroacetabular impingement: Correlation between direct magnetic resonance arthrography and hip arthroscopy.

    Science.gov (United States)

    Crespo Rodríguez, A M; de Lucas Villarrubia, J C; Pastrana Ledesma, M A; Millán Santos, I; Padrón, M

    2015-01-01

    To determine the sensitivity and accuracy of direct MR arthrography in the diagnosis of intra-articular lesions associated with femoroacetabular impingement. We used direct MR arthrography to study 51 patients with femoroacetabular impingement who underwent arthroscopic hip surgery. Surgery demonstrated 37 labral tears, 44 lesions in the labral-chondral transitional zone, and 40 lesions of the articular cartilage. We correlated the findings at preoperative direct MR arthrography with those of hip arthroscopy and calculated the sensitivity, specificity, positive predictive value, negative predictive value, and validity index for direct MR arthrography. The sensitivity and specificity of MR arthrography were 94.5% and 100%, respectively, for diagnosing labral tears, 100% and 87.5%, respectively, for diagnosing lesions of the labral-chondral transition zone, and 92.5% and 54.5%, respectively, for diagnosing lesions of the articular cartilage. The negative predictive value of MR arthrography for lesions of the labral-chondral transitional zone was 100%. MR arthrography accurately defined extensive lesions of the cartilage and the secondary osseous changes (the main factor in poor prognosis), although its diagnostic performance was not so good in small chondral lesions. In patients with femoroacetabular impingement, direct MR arthrography can adequately detect and characterize lesions of the acetabular labrum and of the labral-chondral transitional zone as well as extensive lesions of the articular cartilage and secondary osseous changes. Copyright © 2013 SERAM. Published by Elsevier España, S.L.U. All rights reserved.

  15. Coalescence of resonances in dissipationless resonant tunneling structures and PT-symmetry breaking

    Science.gov (United States)

    Gorbatsevich, A. A.; Shubin, N. M.

    2017-01-01

    We study the phenomenon of spontaneous symmetry breaking in dissipationless resonant tunneling structures (RTS). To describe the quantum transport in this system we apply both the nonequilibrium Green function formalism based on a tight-binding model and a numerical solution of the Schrödinger equation within the envelope wavefunction formalism. An auxiliary non-Hermitian Hamiltonian is introduced. Its eigenvalues determine exactly the transparency peak positions. In spatially symmetric RTS the corresponding auxiliary non-Hermitian Hamiltonian becomes PT-symmetric and possesses real eigenvalues, which can coalesce at exceptional points of this Hamiltonian. A coalescence of the auxiliary non-Hermitian Hamiltonian eigenvalues means a coalescence of perfect resonances in RTS, which can be accompanied be symmetry breaking of the electron wavefunction probability distribution (at a given direction of the particle flow). Also we construct a classification of different types of the coalescence of resonances in terms of the catastrophe theory and investigate the impact of small imperfections (scattering and asymmetry) on these phenomena.

  16. Rotator cuff tears noncontrast MRI compared to MR arthrography

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Ji Hyun; Yoon, Young Cheol [Sungkyunkwan University, School of Medicine, Department of Radiology, Samsung Medical Center, Gangnam-gu, Seoul (Korea, Republic of); Jung, Jee Young [Chungang University School of Medicine, Department of Radiology, Chungang University Hospital, Seoul (Korea, Republic of); Yoo, Jae Chul [Sungkyunkwan University, School of Medicine, Department of Orthopedic Surgery, Samsung Medical Center, Seoul (Korea, Republic of)

    2015-12-15

    To compare the accuracy of indirect magnetic resonance arthrography and noncontrast magnetic resonance imaging for diagnosing rotator cuff tears. In total, 333 patients who underwent noncontrast magnetic resonance imaging or indirect magnetic resonance arthrography were included retrospectively. Two musculoskeletal radiologists evaluated the images for the presence of supraspinatus-infraspinatus and subscapularis tendon tears. The overall diagnostic performance was calculated using the arthroscopic findings as the reference standard. Statistical differences between the diagnostic performances of the two methods were analyzed. Ninety-six and 237 patients who underwent noncontrast magnetic resonance imaging and indirect magnetic resonance arthrography were assigned into groups A and B, respectively. Sensitivity for diagnosing articular-surface partial-thickness supraspinatus-infraspinatus tendon tear was slightly higher in group B than in group A. Statistical significance was confirmed by multivariate analysis using the generalized estimating equation (p = 0.046). The specificity for diagnosing subscapularis tendon tear (85 % vs. 68 %, p = 0.012) and grading accuracy (57 % vs. 40 %, p = 0.005) was higher in group B than in group A; the differences were statistically significant for one out of two readers. Univariate analysis using the generalized estimating equation showed that the accuracy for diagnosing subscapularis tendon tear in group B was higher than in group A (p = 0.042). There were no statistically significant differences between the diagnostic performances of both methods for any other parameters. Indirect magnetic resonance arthrography may facilitate more accurate diagnosis and grading of subscapularis tendon tears compared with noncontrast magnetic resonance imaging. (orig.)

  17. Comparison of MR-arthrography and CT-arthrography in hyaline cartilage-thickness measurement in radiographically normal cadaver hips with anatomy as gold standard.

    Science.gov (United States)

    Wyler, A; Bousson, V; Bergot, C; Polivka, M; Leveque, E; Vicaut, E; Laredo, Jean-Denis

    2009-01-01

    To compare magnetic resonance (MR)-arthrography and multidetector-spiral-computed-tomography (MDSCT)-arthrography in cartilage-thickness measurement, in hips without cartilage loss, with coronal anatomic slices as gold standard. Institutional review board permission to study cadavers of individuals who willed their bodies to science was obtained. Two independent observers measured femoral and acetabular cartilage thicknesses of 12 radiographically normal hips (six women, five men; age range, 52-98 years; mean age, 76.5 years), on MDSCT-arthrographic and MR-arthrographic reformations, and on coronal anatomic slices, excluding regions of cartilage loss. Inter- and intraobserver reproducibilities were determined. Analysis of variance (ANOVA) was used to test differences between MR-arthrographic and MDSCT-arthrographic measurement errors compared to anatomy. By MR-arthrography, cartilage was not measurable at approximately 50% of points on sagittal and transverse sections, compared to 0-6% of the points by MDSCT-arthrography. In the coronal plane, the difference between MDSCT-arthrographic and MR-arthrographic measurement errors was not significant (P=0.93). In the coronal plane, MR-arthrography and MDSCT-arthrography were similarly accurate for measuring hip cartilage thickness.

  18. Value and limits of knee arthrography

    Energy Technology Data Exchange (ETDEWEB)

    Fischedick, O.

    1981-09-01

    In the view of modern knowledges of biomechanic of the knee and the introduce of arthroscopy, the possibilities of arthrography will be discussed. The value of arthrography is not reduced, especially for the cruciate ligaments. Arthroscopy should follow arthrography in uncertain cases.

  19. Supraspinatus tendon tears: comparison of US and MR arthrography with surgical correlation

    Energy Technology Data Exchange (ETDEWEB)

    Ferrari, Francesco S.; Governi, Simone; Burresi, Francesca; Vigni, Francesco; Stefani, Paolo [Department of Radiologic and Orthopaedic-Rehabilitative Sciences, University Hospital Siena (Italy)

    2002-05-01

    The aim of this study was to compare the diagnostic reliability of US with MR arthrography in diagnosing supraspinatus tendon tears. Surgical findings were used as the gold standard in detecting tears. A total of 44 patients were assessed with transverse and longitudinal US scans with respect to the long axis of the rotator cuff tendons and then examined with MR arthrography. This technique involved free-hand injection of contrast medium into the shoulder joint. At surgery 20 incomplete and 24 complete tears were observed. Ultrasound offered good results for the large tears, but its sensitivity decreased proportionally with the size of the tears. Magnetic resonance arthrography correctly diagnosed 43 tears, whereas only one false-negative diagnosis of tendinosis was made for a partial tear on the bursal side. Since it improves the diagnosis of small tears, MR arthrography must be performed on all patients for whom surgical repair is necessary in order to restore normal functions. (orig.)

  20. MRI and arthrography in the evaluation of TMJ disorders

    Energy Technology Data Exchange (ETDEWEB)

    Nakasato, Tatsuhiko; Ehara, Shigeru; Tamakawa, Yoshiharu (Iwate Medical Univ., Morioka (Japan). School of Medicine); Kobayakawa, Takafumi

    1991-08-01

    Arthrosis of the temporomandibular joint (TMJ) is a noninfectious, noninflammatory condition characterized by joint pain, noise (clicking) and abnormal motion. It contains various disease processes, such as abnormalities in the menisci or masticating muscles, subluxation of the condyle and degenerative joint disease. Analysis of the morphology and dynamics of TMJ by means of imaging modalities has become highly advanced since the development of arthrography in the late 1970s. Magnetic resonance imaging (MRI) has become the modality of choice in the evaluation of TMJ owing to the development of surface coils. We retrospectively studied MRI and inferior joint compartment arthrography in the evaluation of TMJ disorders. Nineteen joints of 14 patients included 15 with internal derangement, two with osteoarthrosis and two normal joints. Sagittal MR images were routinely obtained in a resting position and in positions with the mouth half open, and also with the mouth fully open on balanced images. Although perforation of the menisci was difficult to evaluate, MRI and arthrography were equally useful in identifying the shape and position of the meniscus. However, MRI was more reliable in depicting TMJ abnormalities than arthrography. MRI is considered to be the modality of choice in screening arthrosis of TMJ, making the definitive diagnosis of internal derangement and monitoring conservative therapy for arthrosis. (author).

  1. Electron spin resonance of Er{sup 3+} in YBiPt

    Energy Technology Data Exchange (ETDEWEB)

    Martins, G.B. [Universidade Estadual de Campinas (Brazil). Inst. de Fisica; Rao, D. [Universidade Estadual de Campinas (Brazil). Inst. de Fisica; Barberis, G.E. [Universidade Estadual de Campinas (Brazil). Inst. de Fisica; Rettori, C. [Universidade Estadual de Campinas (Brazil). Inst. de Fisica; Duro, R.J. [La Coruna Univ., Ferrol (Spain). Dept. de Ingenieria Industrial; Sarrao, J. [Los Alamos National Lab., NM (United States); Fisk, Z. [Los Alamos National Lab., NM (United States)]|[Florida State Univ., Tallahassee, FL (United States). Nat. High Magnetic Field Lab.; Oseroff, S. [California State Univ., San Diego (United States). Dept. of Physics; Thompson, J.D. [Los Alamos National Lab., NM (United States)]|[Florida State Univ., Tallahassee, FL (United States). Nat. High Magnetic Field Lab.

    1996-07-01

    Electron spin resonance (ESR) experiments at 4.15 K of Er{sup 3+} in YBiPt show that Er{sup 3+} is in a site of cubic local symmetry, with a {Gamma}{sup (3)}{sub 8} ground state and an overall crystal field splitting of {proportional_to}85(10) K. We inferred from the spectra the existence of lattice distortions at the rare-earth (RE) site. These results may help in understanding the heavy-fermion system YbBiPt, which has the same structure as YBiPt. (orig.).

  2. Resonant mode conversion in the waveguides with an unbroken and broken PT-symmetry

    CERN Document Server

    Vysloukh, Victor A

    2014-01-01

    We study resonant mode conversion in the PT-symmetric multimode waveguides, where symmetry breaking manifests itself in sequential destabilization (appearance of the complex eigenvalues) of the pairs of adjacent guided modes. We show that the efficient mode conversion is possible even in the presence of the resonant longitudinal modulation of the complex refractive index. The distinguishing feature of the resonant mode conversion in the PT-symmetric structure is a drastic growth of the width of the resonance curve when the gain/losses coefficient approaches a critical value, at which symmetry breaking occurs. We found that in the system with broken symmetry the resonant coupling between exponentially growing mode with stable higher-order one effectively stabilizes dynamically coupled pair of modes and remarkably diminishes the average rate of the total power growth.

  3. PT-symmetric microring lasers: Self-adapting broadband mode-selective resonators

    CERN Document Server

    Hodaei, Hossein; Heinrich, Matthias; Christodoulides, Demetrios N; Khajavikhan, Mercedeh

    2014-01-01

    We demonstrate experimentally that stable single longitudinal mode operation can be readily achieved in PT-symmetric arrangements of coupled microring resonators. Whereas any active resonator is in principle capable of displaying single-wavelength operation, selective breaking of PT-symmetry can be utilized to systematically enhance the maximum achievable gain of this mode, even if a large number of competing longitudinal or transverse resonator modes fall within the amplification bandwidth of the inhomogeneously broadened active medium. This concept is robust with respect to fabrication tolerances, and its mode selectivity is established without the need for additional components or specifically designed filters. Our results may pave the way for a new generation of versatile cavities lasing at a desired longitudinal resonance. Along these lines, traditionally highly multi-moded microring resonator configurations can be fashioned to suppress all but one longitudinal mode.

  4. Investigations on ferroelectric PMN-PT and PZN-PT single crystals ability for power or resonant actuators.

    Science.gov (United States)

    Lebrun, L; Sebald, G; Guiffard, B; Richard, C; Guyomar, D; Pleska, E

    2004-04-01

    Ferroelectric single crystals of PZN-PT and PMN-PT exhibit outstanding properties: high charge coefficient (dij), high coupling factor (kij) and high strain levels under DC fields. Besides, their mechanical quality factor is believed to be low. Their usefulness for non-resonant or large bandwidth transducers has therefore been previously investigated. However, few studies have been devoted to the dielectric and mechanical losses of single crystals and to their stability under high levels of excitations (electric fields, temperature and mechanical stress). A knowledge and understanding of such performances is needed to determine whether single crystals are suitable materials for power or resonant transducers. In this work, losses and non-linearity versus external excitations are investigated. Dielectric losses and mechanical losses are measured versus electric field for different compositions, orientations. The evolution of d33 and epsilonT33 are obtained versus electric field and temperature for the longitudinal mode. Strain and hysteresis versus sweep mode (up and down) are measured near the resonance frequency using a laser Doppler vibrometer.

  5. Distribution of total radiation widths for neutron resonances of Pt isotopes

    Directory of Open Access Journals (Sweden)

    Koehler P.E.

    2015-01-01

    Full Text Available High quality neutron capture and transmission data were measured on isotopically enriched 192,194,195,196Pt and natural Pt samples at ORELA. R-matrix analysis of this data revealed resonance parameters for 159, 413, 423, 258, and 11 neutron resonances for neutron energies below 5.0, 16.0, 7.5, 16.0, and 5.0 keV for 192,194,195,196,198Pt+n, respectively. Earlier analysis of data on reduced neutron widths, Γ0n, showed that the distributions of Γ0n for 192,194Pt deviate significantly from the Porter-Thomas distribution (PTD predicted by random matrix theory. In this contribution we report on preliminary results of the analysis of distribution of total radiation widths, Γγ, in 192,194,195,196Pt+n reactions. Comparison of experimental data with predictions made within the nuclear statistical model indicates that standard models of Photon Strength Functions (PSFs and Nuclear Level Density predict Γγ distributions which are too narrow. We found that satisfactory agreement between experimental and simulated distributions can be obtained only by a strong suppression of the PSFs at low γ-ray energies and/or by violation of the usual assumption that primary transitions from neutron resonances follow the PTD. The shape of PSFs needed for reproduction of our Γγ data also nicely reproduces spectra from several (n,γ experiments on the neighbor nuclide 198Au.

  6. Comparison of conventional MRI and MR arthrography in the evaluation of wrist ligament tears: A preliminary experience

    Directory of Open Access Journals (Sweden)

    Shivani Pahwa

    2014-01-01

    Full Text Available Aims: To compare conventional magnetic resonance imaging (MRI and direct magnetic resonance (MR arthrography in the evaluation of triangular fibrocartilage complex (TFCC and intrinsic wrist ligament tears. Materials and Methods: T1-weighted, fat suppressed (FS proton density plus T2-weighted (FS PD/T2, 3D multiple-echo data image combination (MEDIC sequences and direct MR arthrography were performed in 53 patients with wrist pain. Images were evaluated for the presence and location of TFCC, scapholunate ligament (SLL and lunatotriquetral ligament (LTL tears, and imaging findings were compared with operative findings in 16 patients who underwent arthroscopy or open surgery (gold standard. Results: Sixteen patients underwent arthroscopy/open surgery: 12 TFCC tears were detected arthroscopically out of which 9 were detected on FS PD/T2 sequence, 10 on MEDIC sequence, and all 12 were detected on MR arthrography. The sensitivities of FS PD/T2, MEDIC sequences, and MR arthrography in the detection of TFCC tears were 75%, 83.3%, and 100%, respectively. Out of the eight arthroscopically confirmed SLL tears, three tears were detected on FS PD/T2 sequence, five on MEDIC sequence, and all eight were visualized on MR arthrography. The sensitivities of FS PD/T2, MEDIC sequences, and MR arthrography in detecting SLL tears were 37.5%, 62.5%, and 100%, respectively. One arthroscopically confirmed LTL tear was diagnosed on FS PD/T2 sequence, three on MEDIC sequence, and all five arthroscopically confirmed LTL tears were detected with MR arthrography. The sensitivities of PD, MEDIC sequences, and MR arthrography in detecting LTL tears were 20%, 40%, and 100%, respectively. Conclusions: MR arthrography is the most sensitive and specific imaging modality for the evaluation of wrist ligament tears.

  7. Observation of double pygmy resonances in $^{195,196}$Pt and enhanced astrophysical reaction rates

    CERN Document Server

    Giacoppo, F; Eriksen, T K; Görgen, A; Guttormsen, M; Hagen, T W; Larsen, A C; Kheswa, B V; Klintefjord, M; Koehler, P E; Nyhus, H T; Renstr\\om, T; Sahin, E; Siem, S; Tornyi, T G

    2014-01-01

    Our measurements of $^{195,196}$Pt $\\gamma$-strength functions show a double-humped enhancement in the $E_{\\gamma}= 4-8$ MeV region. For the first time, the detailed shape of these resonances is revealed for excitation energies in the quasicontinuum. We demonstrate that the corresponding neutron-capture cross sections and astrophysical reaction rates are increased by up to a factor of 2 when these newly observed pygmy resonances are included. These results lend credence to theoretical predictions of enhanced reaction rates due to such pygmy resonances and hence are important for a better understanding of r-process nucleosynthesis.

  8. Transverse waveguide mode suppression for Pt-electrode SAW resonators on quartz and LGS.

    Science.gov (United States)

    Meulendyk, Bennett J; Pereira da Cunha, Mauricio

    2011-12-01

    SAW resonators on ST-X quartz and langasite (LGS) [0°, 144°, 24°] are currently being used for hydrogen fluoride (HF) vapor sensing and high-temperature sensing, respectively. For these applications, the use of Pt-based electrodes allows the resonators to withstand the targeted harsh environments. This work reveals that for Pt-electrode resonators with conventional short-circuit gratings on the aforementioned quartz and LGS orientations, acoustic energy leaks from the grating region to the bus bars, thus degrading the resonator response. To resolve this problem, this paper proposes and implements open-circuit gratings for resonators fabricated with these substrate/metal combinations. The open-circuit gratings guide the acoustic energy within the grating region, resulting in greater quality factors and reduced losses in the resonator response. In addition, scalar potential theory is utilized in this work to identify transverse waveguide modes in the responses of open-circuit grating resonators on quartz and LGS. A transverse waveguide mode dispersion relation was derived to extend the scalar potential theory to account for asymmetry in the slowness curve around the propagation direction. This is the case for several commonly used LGS orientations, in particular LGS [0°, 144°, 24°]. Finally, this work addresses spurious transverse mode mitigation by scaling both the transducer's grating aperture and electrode overlap width. Open circuit grating resonators with appropriately scaled transducer designs were fabricated and tested, resulting in a 71% increase in quality factor and a spurious mode rejection of over 26 dBc for Pt-electrode devices on ST-X quartz. This progress directly translates into better frequency resolution and increased dynamic range for HF vapor sensors and high-temperature SAW devices.

  9. Localization, quantum resonances and ratchet acceleration in a periodically-kicked $\\mathcal{PT}$-symmetric quantum rotator

    CERN Document Server

    Longhi, Stefano

    2016-01-01

    We consider wave transport phenomena in a $\\mathcal{PT}$-symmetric extension of the periodically-kicked quantum rotator model and reveal that dynamical localization assists the unbroken $\\mathcal{PT}$ phase. In the delocalized (quantum resonance) regime, $\\mathcal{PT}$ symmetry is always in the broken phase and ratchet acceleration arises as a signature of unidirectional non-Hermitian transport. An optical implementation of the periodically-kicked $\\mathcal{PT}$-symmetric Hamiltonian, based on transverse beam propagation in a passive optical resonator with combined phase and loss gratings, is suggested to visualize acceleration modes in fractional Talbot cavities.

  10. Thickness dependence of spin torque ferromagnetic resonance in Co{sub 75}Fe{sub 25}/Pt bilayer films

    Energy Technology Data Exchange (ETDEWEB)

    Ganguly, A.; Barman, A., E-mail: abarman@bose.res.in [Thematic Unit of Excellence on Nanodevice Technology, Department of Condensed Matter Physics and Material Sciences, S. N. Bose National Centre for Basic Sciences, Block JD, Sec III, Salt Lake, Kolkata 700 098 (India); Kondou, K., E-mail: kkondou@riken.jp [RIKEN-CEMS, 2-1 Hirosawa, Wako, Saitama 351-0198 (Japan); Sukegawa, H.; Mitani, S. [National Institute for Materials Science (NIMS), Tsukuba, Ibaraki 305-0047 (Japan); Kasai, S. [RIKEN-CEMS, 2-1 Hirosawa, Wako, Saitama 351-0198 (Japan); National Institute for Materials Science (NIMS), Tsukuba, Ibaraki 305-0047 (Japan); Niimi, Y. [Institute for Solid State Physics, University of Tokyo, 5-1-5 Kashiwa-no-ha, Kashiwa, Chiba 277-8581 (Japan); Otani, Y. [RIKEN-CEMS, 2-1 Hirosawa, Wako, Saitama 351-0198 (Japan); Institute for Solid State Physics, University of Tokyo, 5-1-5 Kashiwa-no-ha, Kashiwa, Chiba 277-8581 (Japan)

    2014-02-17

    The spin Hall angle of Pt in Co{sub 75}Fe{sub 25}/Pt bilayer films was experimentally investigated by means of the spin-torque ferromagnetic resonance and the modulation of damping measurements. By comparing the present results with the Ni{sub 80}Fe{sub 20}/Pt system, we found that the ferromagnetic layer underneath the Pt one greatly affects the estimation of the spin Hall angle. We also discuss the spin diffusion length of Pt and the ferromagnetic thickness dependence of the Gilbert damping coefficient.

  11. Conventional angiography in comparison with magnetic resonance tomography and arthroscopy for the diagnosis of knee joint lesion - specific indications?; Die konventionelle Arthrographie im Vergleich zu Magnetresonanztomographie und Arthroskopie bei Kniegelenkbinnenlaesionen: Verbleiben Indikationen?

    Energy Technology Data Exchange (ETDEWEB)

    Koenig, H. [Universitaetsklinikum Steglitz, Radiologische Klinik, Abt. fuer Roentgendiagnostik und Nuklearmedizin, FU Berlin (Germany); Andresen, R. [Universitaetsklinikum Steglitz, Radiologische Klinik, Abt. fuer Roentgendiagnostik und Nuklearmedizin, FU Berlin (Germany); Radmer, S. [Orthopaedisches Institut, Berlin (Germany); Schmidt, M. [Krankenhaus Moabit, Roentgenabteilung, Berlin (Germany); Wolf, K.J. [Universitaetsklinikum Steglitz, Radiologische Klinik, Abt. fuer Roentgendiagnostik und Nuklearmedizin, FU Berlin (Germany)

    1995-03-01

    Twenty-one patients with suspected internal knee joint lesions were examined prospectively. In all patients an MRI was carried out first and was followed within two weeks by an arthrography and an arthrocopy. Lesions of the menisci, cruciate ligaments, hyaline cartilage, and synovial tissues were evaluated. Arthroscopy findings were defined as the `gold standard`. MRI achieved an accuracy of 96.4%, a sensitivity of 93.6%, and a specifity of 92.5%, whereas arthrography achieved an accuracy of 67.8%, a sensitivity of 66.6%, and a specifity of 71.4%. These statistical data as well as the single findings revealed no special indications for arthrography in suspected knee joint lesions. (orig.) [Deutsch] In einer prospektiven Studie wurden insgesamt 21 Patienten mit suspekten Kniegelenksbinnenlaesionen untersucht. Bei allen Patienten erfolgte zunaechst eine Magnetresonanztomographie (MRT), anschliessend innerhalb von zwei Wochen eine Arthrographie und Arthroskopie des Kniegelenks. Beurteilt wurden Laesionen der Meniski, der Kreuzbaender, des hyalinen Gelenkknorpels und des Synovialgewebes. Bezogen auf den Arthroskopiebefund als `Gold-Standard` erreichte die MRT eine Treffsicherheit von 96,4%, eine Sensitivitaet von 93,6% und eine Spezifitaet von 92,5%; dagegen die Arthrographie eine Treffsicherheit von 67,8%, eine Sensitivitaet von 66,6% und eine Spezifitaet von 71,4%. Sowohl eine Uebersicht als auch die Auswertung der Einzelbefunde ergaben keine speziellen Indikationen zur Durchfuehrung einer Kniegelenksarthrographie bei suspekten Binnenlaesionen. (orig.)

  12. Ferromagnetic resonance measurements of (Co/Ni/Co/Pt) multilayers with perpendicular magnetic anisotropy

    Science.gov (United States)

    Sbiaa, R.; Shaw, J. M.; Nembach, H. T.; Bahri, M. Al; Ranjbar, M.; Åkerman, J.; Piramanayagam, S. N.

    2016-10-01

    Multilayers of [Co/Ni(t)/Co/Pt]×8 with varying Ni thickness were investigated for possible use as a free layer in magnetic tunnel junctions and spintronics devices. The thickness t of the Ni sub-layer was varied from 0.3 nm to 0.9 nm and the resulting magnetic properties were compared with (Co/Ni) and (Co/Pt) multilayers. As determined from magnetic force microscopy, magnetometry and ferromagnetic resonance measurements, all multilayers exhibited perpendicular magnetic anisotropy. Compared with (Co/Pt) multilayers, the sample with t of 0.9 nm showed almost the same anisotropy field of μ 0 H k   =  1.15 T but the damping constant was 40% lower. These characteristics make these multilayers attractive for spin torque based magnetoresistive devices with perpendicular anisotropy.

  13. Zero width resonance (spectral singularity) in a complex PT-symmetric potential

    CERN Document Server

    Ahmed, Zafar

    2009-01-01

    We show that the complex PT-Symmetric potential, $V(x)=-V_1 {sech}^2x + iV_2 {sech}x ~\\tanh x, $, entails a single zero-width resonance (spectral singularity) when $V_1+|V_2|=4n^2+4n+{3\\over 4}(n=1,2,3.., |V_2|>|V_1|+ {{sgn}(V_1) \\over 4})$ and the positive resonant energy is given as $E_*={1 \\over 4}[|V_2|-(1/4+V_1)]$.

  14. Antiferromagentic resonance detected by direct current voltages in MnF{sub 2}/Pt bilayers

    Energy Technology Data Exchange (ETDEWEB)

    Ross, Philipp, E-mail: philipp.ross.13@ucl.ac.uk [Walther-Meißner-Institut, Bayerische Akademie der Wissenschaften, Garching (Germany); Schreier, Michael, E-mail: michael.schreier@wmi.badw.de; Lotze, Johannes [Walther-Meißner-Institut, Bayerische Akademie der Wissenschaften, Garching (Germany); Physik-Department, Technische Universität München, Garching (Germany); Huebl, Hans; Goennenwein, Sebastian T. B. [Walther-Meißner-Institut, Bayerische Akademie der Wissenschaften, Garching (Germany); Nanosystems Initiative Munich, Munich (Germany); Gross, Rudolf [Walther-Meißner-Institut, Bayerische Akademie der Wissenschaften, Garching (Germany); Physik-Department, Technische Universität München, Garching (Germany); Nanosystems Initiative Munich, Munich (Germany)

    2015-12-21

    We performed coplanar waveguide-based broadband ferromagnetic resonance experiments on the antiferromagnetic insulator MnF{sub 2}, while simultaneously recording the DC voltage arising in a thin platinum film deposited onto the MnF{sub 2}. The antiferromagnetic resonance is clearly reflected in both the transmission through the waveguide as well as the DC voltage in the Pt strip. The DC voltage remains largely unaffected by field reversal and thus presumably stems from microwave rectification and/or heating effects. However, we identify a small magnetic field orientation dependent contribution, compatible with antiferromagnetic spin pumping theory.

  15. Detection of partial-thickness supraspinatus tendon tears: is a single direct MR arthrography series in ABER position as accurate as conventional MR arthrography?

    Energy Technology Data Exchange (ETDEWEB)

    Schreinemachers, Saskia A. [Onze Lieve Vrouwe Gasthuis, Department of Radiology, Amsterdam (Netherlands); Onze Lieve Vrouwe Gasthuis, Amsterdam (Netherlands); Hulst, Victor P.M. van der; Woude, Henk-Jan van der [Onze Lieve Vrouwe Gasthuis, Department of Radiology, Amsterdam (Netherlands); Willems, W.J. [Onze Lieve Vrouwe Gasthuis, Orthopaedic Surgery, Amsterdam (Netherlands); Bipat, Shandra [University of Amsterdam (NL). Department of Radiology, Academic Medical Center (Netherlands)

    2009-10-15

    The purpose of this study was to retrospectively evaluate sensitivity and specificity of a single magnetic resonance (MR) arthrography series in abduction external rotation (ABER) position compared with conventional MR arthrography for detection of supraspinatus tendon tears, with arthroscopy as gold standard, and to assess interobserver variability. Institutional review board approval was obtained; informed consent was waived. MR arthrograms of 250 patients (170 men and 80 women; mean age, 36 years) were retrospectively and independently evaluated by three observers. Oblique coronal T1-weighted fat-suppressed images, proton density, and T2-weighted images and axial T1-weighted images and oblique sagittal T1-weighted fat-suppressed images were analyzed to detect supraspinatus tendon tears. Separately, a single T1-weighted fat-suppressed oblique axial series in ABER position was evaluated. Both protocols were scored randomly without knowledge of patients' clinical history and arthroscopy results. Tears were subclassified, based on articular surface integrity and extension (Lee classification). Interobserver agreement was assessed by kappa statistics for all patients. Ninety-two of 250 patients underwent arthroscopy; sensitivity and specificity of ABER and conventional MR arthrography were calculated and compared using paired McNemar test. Weighted kappa values of ABER and conventional MR arthrography were 0.48-0.65 and 0.60-0.67, respectively. According to arthroscopy, 69 of 92 patients had an intact cuff, and 23 patients had a cuff tear (16 partial thickness and seven full thickness). There were no statistically significant differences between ABER and conventional MR arthrography regarding sensitivity (48-61% and 52-70%, respectively) and specificity (80-94% and 91-95%). Sensitivity and specificity of a single T1-weighted series in ABER position and conventional MR arthrography are comparable for assessment of rotator cuff tears. (orig.)

  16. C1-2 arthrography

    Energy Technology Data Exchange (ETDEWEB)

    Chevrot, A. [Service de Radiologie B, Hopital Cochin, 75 - Paris (France); Cermakova, E. [Service de Radiologie B, Hopital Cochin, 75 - Paris (France); Vallee, C. [Service de Radiologie B, Hopital Cochin, 75 - Paris (France); Chancelier, M.D. [Service de Radiologie B, Hopital Cochin, 75 - Paris (France); Chemla, N. [Service de Radiologie B, Hopital Cochin, 75 - Paris (France); Rousselin, B. [Service de Radiologie B, Hopital Cochin, 75 - Paris (France); Langer-Cherbit, A. [Service de Radiologie B, Hopital Cochin, 75 - Paris (France)

    1995-08-01

    One hundred patients with the following conditions were studied: cervical pain or neuralgia without radiographic changes, osteoarthritis, rheumatoid arthritis, ankylosing spondylarthritis and diverse conditions. The technique consists of lateral puncture of the posterior aspect of the C1-2 joint with a 20-gauge needle under fluoroscopic control, arthrography using 1 ml contrast medium, and a 1-ml long-acting steroid injection subsequently. The articular cavity has an anterior and a posterior recess. Sometimes the posterior recess is large. In 18% of cases the contralateral joint also opacifies. C1-2 arthrography appears to be an efficient and safe technique for the treatment of upper cervical pain due to C1-2 articular disorders. (orig.)

  17. An overview of MR arthrography with emphasis on the current technique and applicational hints and tips

    Energy Technology Data Exchange (ETDEWEB)

    Sahin, Guelden [Department of Radiology, Faculty of Medicine, Ankara University, Samanpazari, 06100 Ankara (Turkey)]. E-mail: gsahin@medicine.ankara.edu.tr; Demirtas, Mehmet [Department of Hand Surgery, Faculty of Medicine, Ankara University, Samanpazari, 06100 Ankara (Turkey)

    2006-06-15

    Magnetic resonance (MR) arthrography has been investigated in every major peripheral joint of the body, and has been proven to be effective in determining the integrity of intraarticular ligamentous and fibrocartilaginous structures and in the detection or assessment of osteochondral lesions and loose bodies in selected cases. Several methods could be used to create arthrogram effect during MR imaging, however, direct MR arthrography using diluted gadolinium as the contrast agent is the most commonly used technique and is the most reliable of all. MR arthrography is useful for demonstrating labrocapsular-ligamentous abnormalities and distinguishing partial thickness rotator cuff tears from focal full thickness tears in the shoulder, identifying or excluding recurrent tears following meniscal operations in the knee, demonstrating perforations of the triangular fibrocartilage complex (TFCC) and ligaments in the wrist, showing labral tears in the hip, diagnosing ligament tears in the ankle and identifying osteochondral lesions or loose bodies in any of the aforementioned joints. In this article, an overview of techniques of MR arthrography is provided with emphasis on direct MR arthrography using diluted gadolinium as the contrast agent. The current applications of the technique in major peripheral joints are reviewed, with emphasis given to the shoulder joint where the role of this technique has become well established.

  18. Arthrography of the knee joint

    Energy Technology Data Exchange (ETDEWEB)

    Keyl, W.; Jaeger, M.

    1981-10-01

    The standardized examination technique and the clinical problems of the arthrographic mehtod applied on the knee joint is explained by the results obtained in 3000 examinations. Whereas the accuracy of the knee-joint arthrography provides a high degree in cases of meniscus lesions, computer tomography presents in chondral and capsular ligament lesions, and sonography in popliteal cysts better diagnostic information; but in any case arthroscopy gains more and more importance in knee-joint diagnostics.

  19. FIESTA: an MR arthrography celebration of shoulder joint anatomy, variants, and their mimics.

    Science.gov (United States)

    Yu, D; Turmezei, T D; Kerslake, R W

    2013-03-01

    Magnetic resonance (MR) arthrography is currently the gold standard radiological investigation for shoulder joint instability. Not only does this investigation allow for identification of important disease processes, but the reduced slice thickness and increased in-plane resolution allowed by the latest imaging sequences also gives excellent demonstration of shoulder joint internal anatomy. This article describes the technique of MR arthrography of the shoulder practiced at our institution, briefly outlining features of the FIESTA (fast imaging employing steady state acquisition) MR sequence employed, including its advantages and limitations. A pictorial review of shoulder MR arthrography performed with this technique is presented, concentrating on normal shoulder joint internal anatomy and anatomical variants that may mimic pathology. Copyright © 2012 Wiley Periodicals, Inc.

  20. Angle resolved photoelectron distribution of the 1{pi} resonance of CO/Pt(111)

    Energy Technology Data Exchange (ETDEWEB)

    Haarlammert, Thorben; Wegner, Sebastian; Tsilimis, Grigorius; Zacharias, Helmut [Physikalisches Institut, Westfaelische Wilhelms Universitaet, Muenster (Germany); Golovin, Alexander [Institute of Physics, St. Petersburg State University (Russian Federation)

    2009-07-01

    The CO 1{pi} level of a c(4 x 2)-2CO/Pt(111) reconstruction shows a significant resonance when varying the photon energy between h{nu}=23 eV and h{nu}=48 e V. This resonance has not been observed in gas phase measurements or on the Pt(1 10) surface. To investigate the photoelectron distribution of the 1{pi} level high harmonic radiaton has been used. By conversion in rare gases like argon, neon, or helium photon energies of up to 100 eV have been generated at repetition r ates of up to 10 kHz. The single harmonics have been separated and focused by a toroidal grating and directed to the sample surface. A time-of-flight detector with multiple anodes registers the kinetic energies of the emitted photoelectrons and enables the simultaneous detection of multiple emission angles. The angular distributions of photoelectrons emitted from the CO 1{pi} level have been measured for a variety of initial photon energies. Further the angular distributions of the CO 1{pi} level photoelectrons emitted from a CO-Pt{sub 7} cluster have been calculated using the MSX{alpha}-Method which shows good agreement with the ex perimental data.

  1. Resonant Slepton Production Yields CMS $eejj$ and $ejj$ Missing $p_T$ Excesses

    CERN Document Server

    Allanach, B C; Mondal, S; Mitra, M

    2014-01-01

    Recent CMS searches for di-leptoquark production report local excesses of 2.4$\\sigma$ in a $eejj$ channel and 2.6$\\sigma$ in a $ejj$ missing $p_T$ channel. Here, we simultaneously explain both excesses with resonant slepton production in ${\\mathcal R}-$parity violating supersymmetry (SUSY). We consider resonant slepton production, which decays to a lepton and a chargino/neutralino, followed by three-body decays of the neutralino/chargino via an $\\mathcal{R}-$parity violating coupling. There are regions of parameter space which are also compatible at the 95% confidence level (CL) with a 2.8$\\sigma$ $eejj$ excess in a recent CMS $W_R$ search, while being compatible with other direct search constraints. Phase-II of the GERDA neutrinoless double beta decay ($0\

  2. Random-matrix theory of amplifying and absorbing resonators with PT or PTT' symmetry

    CERN Document Server

    Birchall, Christopher

    2012-01-01

    We formulate gaussian and circular random-matrix models representing a coupled system consisting of an absorbing and an amplifying resonator, which are mutually related by a generalized time-reversal symmetry. Motivated by optical realizations of such systems we consider a PT or a PTT' time-reversal symmetry, which impose different constraints on magneto-optical effects, and then focus on five common settings. For each of these, we determine the eigenvalue distribution in the complex plane in the short-wavelength limit, which reveals that the fraction of real eigenvalues among all eigenvalues in the spectrum vanishes if all classical scales are kept fixed. Numerically, we find that the transition from real to complex eigenvalues in the various ensembles display a different dependence on the coupling strength between the two resonators. These differences can be linked to the level spacing statistics in the hermitian limit of the considered models.

  3. Multidetector spiral CT arthrography of the shoulder

    Energy Technology Data Exchange (ETDEWEB)

    Lecouvet, Frederic E. [Departments of Radiology and Orthopaedic Surgery, Cliniques Universitaires Saint-Luc, Universite Catholique de Louvain, Hippocrate Avenue 10/2942, 1200 Brussels (Belgium)], E-mail: frederic.lecouvet@uclouvain.be; Simoni, Paolo; Koutaissoff, Sophie; Vande Berg, Bruno C.; Malghem, Jacques; Dubuc, Jean-Emile [Departments of Radiology and Orthopaedic Surgery, Cliniques Universitaires Saint-Luc, Universite Catholique de Louvain, Hippocrate Avenue 10/2942, 1200 Brussels (Belgium)

    2008-10-15

    Although MR imaging and MR arthrography are the first choice modalities for shoulder imaging, CT arthrography (CTA) may be used successfully to address many clinical questions. The advent of submillimeter multiple detector CT technology and subsequent excellent three-plane resolution has considerably increased the quality of CTA examinations and has propelled this technique to the forefront in a growing number of indications. The combined use of iodinated contrast material for fluoroscopic confirmation of the articular position of the needle before injection of gadolinium chelates for MR arthrography offers the unique opportunity to compare CTA and MRA findings in carefully selected cases. This paper illustrates capabilities and limits of CTA for the study of rotator cuff tears, shoulder instability, cartilage lesions, anatomical variants and abnormalities of the glenoid labrum, with correlations to MR arthrography and surgical findings.

  4. Shoulder, hip, and knee arthrography needle placement using fluoroscopic guidance: practice patterns of musculoskeletal radiologists in North America

    Energy Technology Data Exchange (ETDEWEB)

    Shortt, Conor P. [Thomas Jefferson University Hospital, Department of Radiology, Philadelphia, PA (United States); Hospital of the University of Pennsylvania, Department of Radiology, Philadelphia, PA (United States); Morrison, William B.; Deely, Diane M.; Gopez, Angela G.; Zoga, Adam C. [Thomas Jefferson University Hospital, Department of Radiology, Philadelphia, PA (United States); Roberts, Catherine C. [Mayo Clinic College of Medicine, Department of Radiology, Phoenix, AZ (United States)

    2009-04-15

    The aim of this study was to evaluate the range of techniques used by radiologists performing shoulder, hip, and knee arthrography using fluoroscopic guidance. Questionnaires on shoulder, hip, and knee arthrography were distributed to radiologists at a national radiology meeting. We enquired regarding years of experience, preferred approaches, needle gauge, gadolinium dilution, and volume injected. For each approach, the radiologist was asked their starting and end needle position based on a numbered and lettered grid superimposed on a radiograph. Sixty-eight questionnaires were returned. Sixty-eight radiologists performed shoulder and hip arthrography, and 65 performed knee arthrograms. Mean experience was 13.5 and 12.8 years, respectively. For magnetic resonance arthrography, a gadolinium dilution of 1/200 was used by 69-71%. For shoulder arthrography, an anterior approach was preferred by 65/68 (96%). The most common site of needle end position, for anterior and posterior approaches, was immediately lateral to the humeral cortex. A 22-gauge needle was used by 46/66 (70%). Mean injected volume was 12.7 ml (5-30). For hip arthrography, an anterior approach was preferred by 51/68 (75%). The most common site of needle end position, for anterior and lateral approaches, was along the lateral femoral head/neck junction. A 22-gauge needle was used by 53/68 (78%). Mean injected volume was 11.5 ml (5-20). For knee arthrography, a lateral approach was preferred by 41/64 (64%). The most common site of needle end position, for lateral and medial approaches, was mid-patellofemoral joint level. A 22-gauge needle was used by 36/65 (56%). Mean injected volume was 28.2 ml (5-60). Arthrographic approaches for the shoulder, hip, and knee vary among radiologists over a wide range of experience levels. (orig.)

  5. Surface acoustic load sensing using a face-shear PIN-PMN-PT single-crystal resonator.

    Science.gov (United States)

    Kim, Kyungrim; Zhang, Shujun; Jiang, Xiaoning

    2012-11-01

    Pb(In(0.5)Nb(0.5))O(3)-Pb(Mg(1/3)Nb(2/3))O(3)-PbTiO(3) (PIN-PMN-PT) resonators for surface acoustic load sensing are presented in this paper. Different acoustic loads are applied to thickness mode, thickness-shear mode, and face-shear mode resonators, and the electrical impedances at resonance and anti-resonance frequencies are recorded. More than one order of magnitude higher sensitivity (ratio of electrical impedance change to surface acoustic impedance change) at the resonance is achieved for the face-shear-mode resonator compared with other resonators with the same dimensions. The Krimholtz, Leedom, and Matthaei (KLM) model is used to verify the surface acoustic loading effect on the electrical impedance spectrum of face-shear PIN-PMN-PT single-crystal resonators. The demonstrated high sensitivity of face-shear mode resonators to surface loads is promising for a broad range of applications, including artificial skin, biological and chemical sensors, touch screens, and other touch-based sensors.

  6. Characterization of PMN-PT piezoelectric single crystal and PMN-PT 1-3 composite at elevated temperatures by electrical impedance resonance analysis.

    Science.gov (United States)

    Wu, Zhengbin; Xi, Kui

    2014-07-01

    In this paper, lead magnesium niobate-lead titanate (PMN-PT) piezoelectric single crystal and its 1-3 composite counterpart were characterized and analyzed under different stable temperatures using both a Simulated Annealing (SA) optimization algorithm and the commercial software PRAP (Piezoelectric Resonance Analysis Program). Electrical impedance resonance characteristics of the two material samples over the range 25-125 °C were measured. The correlation between experimental data and numerical fits derived from both SA and PRAP is considered. Calculation of the determination coefficient (R1(2)) between numerically fitted and measured results is above 95% for both methods. Furthermore, variations in the number of data values used for the fit introduced no more than 3.1% uncertainty on the calculated material parameters. It is found that the complex material parameters of PMN-PT composite are more dependent on temperature than the single crystal. The phase transition of the PMN-PT, which is close to 90 °C, has an effect on the high temperature material characteristics of both piezoelectric materials. These calculated complex material parameters can be used for the design of ultrasonic transducers for elevated temperature applications.

  7. Lesions of the rotator cuff footprint: diagnostic performance of MR arthrography compared with arthroscopy.

    Science.gov (United States)

    Stoppino, L P; Ciuffreda, P; Rossi, M; Lelario, M; Bristogiannis, C; Vinci, R; Genovese, E A; Macarini, L

    2013-08-01

    To evaluate the diagnostic performance of magnetic resonance arthrography (MR-A) of the shoulder in the diagnosis of rotator cuff tears involving the humeral insertion of the supraspinatus and infraspinatus tendon (footprint), using arthroscopy as the reference standard. The study population included 90 consecutive patients with history and clinical diagnosis of instability of the shoulder, rotator cuff tear or posterosuperior glenoid impingement. A total of 108 MR arthrograms were performed, since 18 patients had undergone a bilateral procedure. Arthroscopy, which was performed within 45 days after MR-A, was used as the reference standard. Sensitivity, specificity, accuracy, positive and negative predictive values were then calculated. Magnetic resonance arthrography showed a sensitivity of 92 % and a specificity of 78 % for the overall detection of tears involving the rotator cuff footprint. The diagnostic accuracy was 90 %, and the positive and negative predictive values were 95 and 64 %, respectively. Ten lesions were non-classifiable on surgery, of which eight were non-classifiable on MR-A also. Magnetic resonance arthrography is extremely accurate for the detection and classification of rotator cuff footprint tears. Most of these lesions are articular-sided (partial articular-sided supraspinatus tendon avulsion lesions) with predominance in younger patients and concealed type of tear (concealed interstitial delamination lesions).

  8. MR arthrography of the ankle joint; MR-Arthrographie des Sprunggelenkes

    Energy Technology Data Exchange (ETDEWEB)

    Trattnig, S.; Rand, T.; Breitenseher, M.; Ba-Ssalamah, A.; Schick, S.; Imhof, H. [Universitaetsklinik fuer Radiodiagnostik, AKH-Wien (Austria)

    1999-01-01

    Due to its superior soft tissue contrast conventional MRI is the imaging method of choice in the evaluation of ankle joint disorders. Conventional MR imaging can accurately demonstrate normal or acutely injured ligaments; however, in subacute and chronic injury joint fluid necessary for delineation of injured ligaments is absent and MR arthrography should be performed. MR arthrography uses the intraarticular injection of contrast material to distend the joint, yielding improved discrimination of intraarticular structures. This joint distension with MR arthrography is also helpful in the staging of osteochondritis dissecans, since in cases of unstable lesions tracking of contrast material into the interface can be more easily demonstrated. Finally, high contrast and joint distension by MR arthrography improves the detection of intraarticular loose bodies, which often require surgery. MR artrography, although invasive, may provide additional information in various ankle joint disorders. (orig.) [Deutsch] Aufgrund des ausgezeichneten Weichteilkontrastes ist die konventionelle MRT die bildgebende Methode der Wahl in der Beurteilung von Sprunggelenkserkrankungen. Die konventionelle MRT kann zuverlaessig normale und akut verletzte Ligamente darstellen. Im subakuten und chronischen Stadium der Verletzung fehlt jedoch oft die Gelenksfluessigkeit die fuer eine exakte Abgrenzung der verletzten Ligamente notwendig ist. Die MR-Arthrographie sollte in diesen Faellen durchgefuehrt werden, da die intraartikulaere KM-Applikation den Gelenksraum distendiert mit verbesserter Unterscheidbarkeit intraartikulaerer Strukturen. Diese Gelenksdistension mit der MR-Arthrographie ist auch in der Stadiumbeurteilung der Osteochondritis dissecans hilfreich, da in Faellen von instabilen Laesionen eine KM-Umspuelung des Dissekats leichter dargestellt werden kann. Schliesslich verbessert die MR-Arthrographie aufgrund des hohen Kontrastes und der Gelenksdistension auch den Nachweis von

  9. Arthrography

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    Full Text Available ... during x-ray examinations to use the lowest radiation dose possible while producing the best images for evaluation. National and international radiology protection organizations continually review ...

  10. Arthrography

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    Full Text Available ... evaluation. National and international radiology protection organizations continually review and update the technique standards used by radiology ... the possible charges you will incur. Web page review process: This Web page is reviewed regularly by ...

  11. Arthrography

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    Full Text Available ... being imaged, send and receive radio waves, producing signals that are detected by the coils. The electric current does not come in contact with the patient. A computer then processes the signals and generates a series of images, each of ...

  12. Arthrography

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    Full Text Available ... the body. X-rays are the oldest and most frequently used form of medical imaging. Fluoroscopy makes ... involves taking radiographs for documentation. These images are most often stored and viewed electronically. Similarly, direct MR ...

  13. Arthrography

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    Full Text Available ... magnetic field of the MRI unit, metal and electronic items are not allowed in the exam room. ... tell the technologist if you have medical or electronic devices in your body. These objects may interfere ...

  14. Arthrography

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    Full Text Available ... to numb the joint area. You may feel pressure or even pain when the needle is advanced ... but rare, complication of MRI believed to be caused by the injection of high doses of gadolinium- ...

  15. Arthrography

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    Full Text Available ... procedure. top of page What does the equipment look like? The equipment typically used for this examination ... almost no risk to the average patient when appropriate safety guidelines are followed. If sedation is used, ...

  16. Arthrography

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    Full Text Available ... and have claustrophobia (fear of enclosed spaces) or anxiety, you may want to ask your physician about ... the magnet. Some MRI units, called short-bore systems , are designed so that the magnet does not ...

  17. Arthrography

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  18. Arthrography

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    Full Text Available ... of which shows a thin slice of the body. The images can then be studied from different angles by ... It is normal for the area of your body being imaged to feel slightly warm, but ... still while the images are being obtained, which is typically only a ...

  19. Arthrography

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    Full Text Available ... risks of excessive sedation. However, the technologist or nurse will monitor your vital signs to minimize this ... possible charges you will incur. Web page review process: This Web page is reviewed regularly by a ...

  20. Arthrography

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    Full Text Available ... a powerful magnetic field, radiofrequency pulses and a computer to produce detailed pictures of organs, soft tissues, ... The images can then be examined on a computer monitor connected to an image archive (PACS system) ...

  1. Arthrography

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    Full Text Available ... current x-ray images for diagnosis and disease management. Fluoroscopy uses a continuous or pulsed x-ray beam to create a sequence of images that are projected onto a fluorescent screen, or television-like monitor. When used with a contrast material, which clearly defines the area being examined by ...

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    Full Text Available ... understanding of the possible charges you will incur. Web page review process: This Web page is reviewed regularly by a physician with ... not responsible for the content contained on the web pages found at these links. About Us | Contact ...

  3. Arthrography

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    Full Text Available ... of which shows a thin slice of the body. The images can then be studied from different angles by ... doctor if they persist after two days. Vigorous exercise is not recommended for at least 24 hours ...

  4. Arthrography

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    Full Text Available ... doctor if they persist after two days. Vigorous exercise is not recommended for at least 24 hours ... is also recommended that you refrain from vigorous exercise of the joint for about two weeks. top ...

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    Full Text Available ... evaluation. National and international radiology protection organizations continually review and update the technique standards used by radiology ... the possible charges you will incur. Web page review process: This Web page is reviewed regularly by ...

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    Full Text Available ... allergies – especially to contrast materials. Leave jewelry at home and wear loose, comfortable clothing. You may be ... Jewelry and other accessories should be left at home, if possible, or removed prior to the MRI ...

  7. Arthrography

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    Full Text Available ... include a variety of needles, syringes and a water-soluble contrast material. top of page How does ... possible charges you will incur. Web page review process: This Web page is reviewed regularly by a ...

  8. Arthrography

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    Full Text Available ... an ankle arthrogram. View full size with caption Pediatric Content Some imaging tests and treatments have special pediatric considerations. The teddy bear denotes child-specific content. ...

  9. Arthrography

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    Full Text Available ... computer then processes the signals and generates a series of images, each of which shows a thin ... few seconds to a few minutes at a time. You will know when images are being recorded ...

  10. Arthrography

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    ... any kind, such as allergy to iodine or x-ray contrast material, drugs, food, or environmental agents. However, the contrast ... the procedure. The video is produced by the x-ray machine and a detector that is suspended over a table on which ...

  11. Arthrography

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    Full Text Available ... film sheets (much like a large photographic negative). Today, most images are digital files that are stored ... standards used by radiology professionals. Modern x-ray systems have very controlled x-ray beams and dose ...

  12. Arthrography

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    Full Text Available ... of page What are some common uses of the procedure? Arthrographic images help physicians evaluate alterations in ... after your procedure. top of page What does the equipment look like? The equipment typically used for ...

  13. Arthrography

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    Full Text Available ... rays. top of page What are some common uses of the procedure? Arthrographic images help physicians evaluate ... a table on which the patient lies. The traditional MRI unit is a large cylinder-shaped tube ...

  14. Arthrography

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    Full Text Available ... doctor if they persist after two days. Vigorous exercise is not recommended for at least 24 hours after the exam as there is a slight increased risk of dislocation after your procedure. Typically, if an ...

  15. Arthrography

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    Full Text Available ... pictures of organs, soft tissues, bone and virtually all other internal body structures. The images can then ... include: jewelry, watches, credit cards and hearing aids, all of which can be damaged pins, hairpins, metal ...

  16. Arthrography

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    Full Text Available ... physician and technologist if they may be pregnant. Children younger than 13 may need to be sedated ... also screened for safety in the magnetic environment. Children will be given appropriately sized earplugs or headphones ...

  17. Arthrography

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    Full Text Available ... clothing that might interfere with the x-ray images. Women should always inform their physician and x-ray ... of which shows a thin slice of the body. The images can then be studied from different angles by ...

  18. Arthrography

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    Full Text Available ... not responsible for the content contained on the web pages found at these links. About Us | Contact Us | FAQ | Privacy | Terms of Use | Links | Site Map Copyright © 2017 Radiological Society of North America, ...

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    Full Text Available ... other physician will be available for immediate assistance. A Word About Minimizing Radiation Exposure Special care is ... encourage linking to this site. × Recommend RadiologyInfo to a friend Send to (friend's e-mail address): From ( ...

  20. Arthrography

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    Full Text Available ... These items include: jewelry, watches, credit cards and hearing aids, all of which can be damaged pins, ... the joint as it is filled and possibly hear gurgling when the joint is moved. If your ...

  1. Arthrography

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    Full Text Available ... ear) implant some types of clips used for brain aneurysms some types of metal coils placed within ... may distort images of the facial area or brain, so the radiologist should be aware of them. ...

  2. Arthrography

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    Full Text Available ... standards used by radiology professionals. Modern x-ray systems have very controlled x-ray beams and dose control methods to minimize stray (scatter) radiation. This ensures ...

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    Full Text Available ... which may be sent to a laboratory for analysis. Aspiration is typically performed when an infection is ... type your comment or suggestion into the following text box: Comment: E-mail: Area code: Phone no: ...

  4. Arthrography

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    Full Text Available ... and have claustrophobia (fear of enclosed spaces) or anxiety, you may want to ask your physician about ... the magnet. Some MRI units, called short-bore systems , are designed so that the magnet does not ...

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    Full Text Available ... metallic items, which can distort MRI images removable dental work pens, pocket knives and eyeglasses body piercings ... may also be asked to remove jewelry, removable dental appliances, eye glasses and any metal objects or ...

  6. Arthrography

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    Full Text Available ... may sense a temporary metallic taste in their mouth after the contrast injection. If you do not ... vessel or a nerve adjacent to the joint. Injury to these structures, however, is minimal particularly when ...

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    Full Text Available ... community, you can search the ACR-accredited facilities database . This website does not provide cost information. The ... entered here will not be used for any purpose other than this referral.

  8. Arthrography

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    Full Text Available ... or x-ray contrast material, drugs, food, or environmental agents. However, the contrast material used for an ... are also screened for safety in the magnetic environment. Children will be given appropriately sized earplugs or ...

  9. Arthrography

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    Full Text Available ... metallic items, which can distort MRI images removable dental work pens, pocket knives and eyeglasses body piercings In most cases, an MRI exam is safe for patients with metal implants, except for a few types. People with the ...

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    Full Text Available ... include a variety of needles, syringes and a water-soluble contrast material. top of page How does ... current x-ray images for diagnosis and disease management. Fluoroscopy uses a continuous or pulsed x-ray ...

  11. Arthrography

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    Full Text Available ... a form of radiation like light or radio waves. X-rays pass through most objects, including the ... the body being imaged, send and receive radio waves, producing signals that are detected by the coils. ...

  12. Arthrography

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    Full Text Available ... very effective at detecting disease within the ligaments, tendons and cartilage. It may be indirect, where contrast ... the structures within the joints such as ligaments, tendons and cartilage. This is particularly true for the ...

  13. Arthrography

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    Full Text Available ... bore which can be more comfortable for larger size patients or patients with claustrophobia. Other MRI machines ... images to plan an ankle arthrogram. View full size with caption Pediatric Content Some imaging tests and ...

  14. Arthrography

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    Full Text Available ... include a variety of needles, syringes and a water-soluble contrast material. top of page How does ... the cause of chronic joint pain and what therapies may be effective. It is also recommended that ...

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    Full Text Available ... earplugs, while others use headphones to reduce the intensity of the sounds made by the MRI machine. ... be asked to keep a log of your level of joint discomfort over the following days or ...

  16. Arthrography

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    Full Text Available ... material. top of page How does the procedure work? X-rays are a form of radiation like ... might be obscured by bone with other imaging methods. The contrast material used in MRI exams is ...

  17. Arthrography

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    Full Text Available ... utilize ionizing radiation. Instead, radiofrequency pulses re-align hydrogen atoms that naturally exist within the body while ... any chemical changes in the tissues. As the hydrogen atoms return to their usual alignment, they emit ...

  18. Arthrography

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    Full Text Available ... E-mail: Area code: Phone no: Thank you! Images × Image Gallery Musculoskeletal radiologist using fluoroscopic images to plan ... address): From (your name): Your e-mail address: Personal message (optional): Bees: Wax: Notice: RadiologyInfo respects your ...

  19. Arthrography

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    Full Text Available ... one hour. top of page What will I experience during and after the procedure? You will experience a slight pinprick and may feel a momentary ... discomfort when it is inserted and you may experience some bruising. There is also a very small ...

  20. Arthrography

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    Full Text Available ... Examples include but are not limited to: artificial heart valves implanted drug infusion ports artificial limbs or ... with fluoroscopy or ultrasound. In some cases, additional medications, such as anti-inflammatory steroids, may be injected ...

  1. Arthrography

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    Full Text Available ... Examples include but are not limited to: artificial heart valves implanted drug infusion ports artificial limbs or ... fluid from the joint. If steroids or anesthetic medications are injected into ... no side effects in the typical diagnostic range for this exam. ...

  2. Arthrography

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    Full Text Available ... through the body, recording an image on photographic film or a special detector. Different parts of the ... recently, x-ray images were maintained on large film sheets (much like a large photographic negative). Today, ...

  3. Arthrography

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    Full Text Available ... include a variety of needles, syringes and a water-soluble contrast material. top of page How does ... period is necessary. You may resume your usual activities and normal diet immediately after the exam. On ...

  4. Arthrography

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    Full Text Available ... radiologist or technologist may ask if you have asthma, or allergies of any kind, such as an ... physician and technologist if they may be pregnant. Children younger than 13 may need to be sedated ...

  5. Arthrography

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    Full Text Available ... evaluate and diagnose joint conditions and unexplained pain. It is very effective at detecting disease within the ligaments, tendons and cartilage. It may be indirect, where contrast material is injected ...

  6. Arthrography

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    Full Text Available ... two weeks. top of page Who interprets the results and how do I get them? A radiologist , ... care or referring physician , who will discuss the results with you. Follow-up examinations may be necessary. ...

  7. Arthrography

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    Full Text Available ... pregnant. Many imaging tests are not performed during pregnancy so as not to expose the fetus to ... See the Safety page for more information about pregnancy and x-rays. Though MRI does not use ...

  8. Arthrography

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    Full Text Available ... will hear and feel loud tapping or thumping sounds when the coils that generate the radiofrequency pulses ... use headphones to reduce the intensity of the sounds made by the MRI machine. You may be ...

  9. Arthrography

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    Full Text Available ... field of the MRI unit, metal and electronic items are not allowed in the exam room. In addition to affecting the MRI images, ... damaged pins, hairpins, metal zippers and similar metallic items, which can distort ... In most cases, an MRI exam is safe for patients with metal implants, except ...

  10. Arthrography

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    Full Text Available ... radiologist or other physician will be available for immediate assistance. If you experience allergic symptoms, a radiologist or other physician will be available for immediate assistance. After the examination, you may experience swelling ...

  11. Arthrography

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    Full Text Available ... aneurysms some types of metal coils placed within blood vessels nearly all cardiac defibrillators and pacemakers You should ... vessel or a nerve adjacent to the joint. Injury to these structures, however, is minimal particularly when ...

  12. Arthrography

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    Full Text Available ... current x-ray images for diagnosis and disease management. Fluoroscopy uses a continuous or pulsed x-ray ... may feel a momentary burning if a local anesthesia is used to numb the joint area. You ...

  13. Arthrography

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    Full Text Available ... a powerful magnetic field, radiofrequency pulses and a computer to produce detailed pictures of organs, soft tissues, ... The images can then be examined on a computer monitor connected to an image archive (PACS system) ...

  14. Arthrography

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    Full Text Available ... during an MRI scan, but this is rare. Tooth fillings and braces usually are not affected by ... joint area. You may feel pressure or even pain when the needle is advanced into the joint. ...

  15. Arthrography

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    Full Text Available ... are easily accessible and are frequently compared to current x-ray images for diagnosis and disease management. ... magnetic field is produced by passing an electric current through wire coils in most MRI units. Other ...

  16. Arthrography

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    Full Text Available ... inflammation and provide physicians additional information about possible sources of pain. top of page How should I ... or patients with claustrophobia. Other MRI machines are open on the sides (open MRI). Open units are ...

  17. Arthrography

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    Full Text Available ... allergy to iodine or x-ray contrast material, drugs, food, or environmental agents. However, the contrast material ... are not limited to: artificial heart valves implanted drug infusion ports artificial limbs or metallic joint prostheses ...

  18. Arthrography

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    Full Text Available ... it is useful to bring that to the attention of the scheduler before the exam and bring ... images and send a signed report to your primary care or referring physician , who will discuss the ...

  19. Arthrography

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    Full Text Available ... help evaluate and diagnose joint conditions and unexplained pain. It is very effective at detecting disease within ... often used to help diagnose persistent, unexplained joint pain or discomfort. In some cases, local anesthetic medications ...

  20. Arthrography

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    Full Text Available ... radiation like light or radio waves. X-rays pass through most objects, including the body. Once it ... organs, allow more of the x-rays to pass through them. As a result, bones appear white ...

  1. Arthrography

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    Full Text Available ... in patients with very poor kidney function. Careful assessment of kidney function before considering a contrast injection minimizes the risk of this very rare complication. There is a ...

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    Full Text Available ... it is useful to bring that to the attention of the technologist or scheduler before the exam. ... image contrast to white), this special x-ray technique makes it possible for the physician to view ...

  3. Arthrography

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    Full Text Available ... examination consists of a radiographic table, one or two x-ray tubes and a television-like monitor ... speak with you at all times using a two-way intercom. Many MRI centers allow a friend ...

  4. Arthrography

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    Full Text Available ... Please note RadiologyInfo.org is not a medical facility. Please contact your physician with specific medical questions ... your community, you can search the ACR-accredited facilities database . This website does not provide cost information. ...

  5. Arthrography

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    Full Text Available ... of small internal structures. This leads to improved evaluation of diseases or conditions within the joint. It ... joint which becomes clearly visible during x-ray evaluation, allowing the radiologist to assess the anatomy and ...

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    Full Text Available ... recently had surgery. Some conditions, such as severe kidney disease, may prevent you from being given MRI or ... frequently compared to current x-ray images for diagnosis and disease management. Fluoroscopy uses a continuous or ...

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    Full Text Available ... computer monitor connected to an image archive (PACS system) or printed or copied to CD. MRI does ... the magnet. Some MRI units, called short-bore systems , are designed so that the magnet does not ...

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    Full Text Available ... standards used by radiology professionals. Modern x-ray systems have very controlled x-ray beams and dose ... Send us your feedback Did you find the information you were looking for? Yes No Please type ...

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    Full Text Available ... joint thus allowing for enhanced imaging of small internal structures. This leads to improved evaluation of diseases ... makes it possible to see bones, joints and internal organs in real time. When iodine contrast is ...

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    Full Text Available ... current x-ray images for diagnosis and disease management. Fluoroscopy uses a continuous or pulsed x-ray ... are in the scanner without causing any chemical changes in the tissues. As the hydrogen atoms return ...

  11. Arthrography

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    Full Text Available ... for about two weeks. top of page Who interprets the results and how do I get them? ... radiologist , a physician specifically trained to supervise and interpret radiology examinations, will analyze the images and send ...

  12. Arthrography

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    Full Text Available ... ray called fluoroscopy to guide and evaluate the injection of iodine contrast material directly into the joint. ... MRI) or computed tomography (CT) following contrast material injection into the joint. An x-ray (radiograph) is ...

  13. Arthrography

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    Full Text Available ... X-rays are a form of radiation like light or radio waves. X-rays pass through most ... material and experience hives, itchy eyes or other reactions. If you experience allergic symptoms, notify the technologist. ...

  14. Arthrography

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    Full Text Available ... related pain or inflammation and provide physicians additional information about possible sources of pain. top of page ... the baby. See the Safety page for more information about pregnancy and x-rays. Though MRI does ...

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    Full Text Available ... doctor if there’s a possibility that you are pregnant and discuss any recent illnesses, medical conditions, medications ... if there is any possibility that they are pregnant. Many imaging tests are not performed during pregnancy ...

  16. Arthrography

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    Full Text Available ... doctor if they persist after two days. Vigorous exercise is not recommended for at least 24 hours ... is also recommended that you refrain from vigorous exercise of the joint for about two weeks. top ...

  17. Arthrography

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    Full Text Available ... a large photographic negative). Today, most images are digital files that are stored electronically. These stored images ... a physician specially trained to supervise and interpret radiology examinations, will often use fluoroscopy or ultrasound to ...

  18. Arthrography

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    Full Text Available ... images for evaluation. National and international radiology protection organizations continually review and update the technique standards used ... information you were looking for? Yes No Please type your comment or suggestion into the following text ...

  19. Arthrography

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    Full Text Available ... a large photographic negative). Today, most images are digital files that are stored electronically. These stored images ... field is not harmful in itself, implanted medical devices that contain metal may malfunction or cause problems ...

  20. Arthrography

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    Full Text Available ... Some conditions, such as severe kidney disease, may prevent you from being given MRI or CT arthrogram ... injection. If you do not require sedation, no recovery period is necessary. You may resume your usual ...

  1. Arthrography

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    Full Text Available ... up examinations may be necessary. Your doctor will explain the exact reason why another exam is requested. Sometimes a follow-up exam is done because a potential abnormality needs further evaluation with additional views or a ...

  2. Arthrography

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    Full Text Available ... which may be sent to a laboratory for analysis. Aspiration is typically performed when an infection is ... images for evaluation. National and international radiology protection organizations continually review and update the technique standards used ...

  3. Arthrography

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    Full Text Available ... to numb the joint area. You may feel pressure or even pain when the needle is advanced ... intercom. Many MRI centers allow a friend or parent to stay in the room as long as ...

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    Full Text Available ... may be required prior to sedation. You should plan to have a relative or friend drive you ... Image Gallery Musculoskeletal radiologist using fluoroscopic images to plan an ankle arthrogram. View full size with caption ...

  5. Arthrography

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    Full Text Available ... choose to use these for reference. Next, the skin around the joint is cleansed with antiseptic and ... a very small chance of irritation of your skin at the site of the IV tube insertion. ...

  6. Arthrography

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    Full Text Available ... produced. MRI uses a powerful magnetic field, radiofrequency pulses and a computer to produce detailed pictures of ... MRI does not utilize ionizing radiation. Instead, radiofrequency pulses re-align hydrogen atoms that naturally exist within ...

  7. Arthrography

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    Full Text Available ... ray evaluation, allowing the radiologist to assess the anatomy and function of the joint. Although the injection ... to detect and identify any metal objects. In general, metal objects used in orthopedic surgery pose no ...

  8. Arthrography

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    Full Text Available ... it fills the entire joint which becomes clearly visible during x-ray evaluation, allowing the radiologist to ... X-rays are a form of radiation like light or radio waves. X-rays pass through most ...

  9. Arthrography

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    Full Text Available ... any questions. Some implanted devices require a short period of time after placement (usually six weeks) before ... If you do not require sedation, no recovery period is necessary. You may resume your usual activities ...

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    Full Text Available Toggle navigation Test/Treatment Patient Type Screening/Wellness Disease/Condition Safety En Español More Info Images/Videos About Us News Physician ... An x-ray (radiograph) is a noninvasive medical test that helps physicians diagnose and treat medical conditions. ...

  11. Arthrography

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    Full Text Available ... over time. Follow-up examinations are sometimes the best way to see if treatment is working or ... the lowest radiation dose possible while producing the best images for evaluation. National and international radiology protection ...

  12. Arthrography

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    Full Text Available ... choose to use these for reference. Next, the skin around the joint is cleansed with antiseptic and ... a very small chance of irritation of your skin at the site of the IV tube insertion. ...

  13. Arthrography

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    Full Text Available ... of the radiation while soft tissue, such as muscle, fat and organs, allow more of the x- ... and cartilage. This is particularly true for the shoulder in the setting of shoulder dislocation and in ...

  14. Arthrography

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    Full Text Available ... a non-arthrographic exam is felt to be inadequate in assessing a joint abnormality. There are several ... You should tell the technologist if you have medical or electronic devices in your ... does the equipment look like? The equipment typically used for this ...

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    Full Text Available ... other physician will be available for immediate assistance. A Word About Minimizing Radiation Exposure Special care is ... encourage linking to this site. × Recommend RadiologyInfo to a friend Send to (friend's e-mail address): From ( ...

  16. Arthrography

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    Full Text Available ... or internal organs in motion. Still images or movies are also captured and stored electronically on a ... the area. After the local anesthetic has taken effect, a longer needle is then inserted into the ...

  17. Arthrography

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    Full Text Available ... used in tattoos may contain iron and could heat up during an MRI scan, but this is ... to get a better understanding of the possible charges you will incur. Web page review process: This ...

  18. Arthrography

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    Full Text Available ... material. top of page How does the procedure work? X-rays are a form of radiation like ... as long as they are also screened for safety in the magnetic environment. Children will be given ...

  19. Arthrography

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    Full Text Available ... of the radiation while soft tissue, such as muscle, fat and organs, allow more of the x- ... to current x-ray images for diagnosis and disease management. Fluoroscopy uses a continuous or pulsed x- ...

  20. Arthrography

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    Full Text Available ... that might interfere with the x-ray images. Women should always inform their physician and x-ray ... rays. Though MRI does not use ionizing radiation, women should still inform their physician and technologist if ...

  1. Arthrography

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    Full Text Available ... illnesses, medical conditions, medications you’re taking, and allergies – especially to contrast materials. Leave jewelry at home ... and if you have any kidney problems or allergies, especially to iodinated or gadolinium-based contrast materials. ...

  2. Arthrography

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    Full Text Available ... Leave jewelry at home and wear loose, comfortable clothing. You may be asked to wear a gown. ... will be asked to remove some of your clothes and to wear a gown during the exam. ...

  3. Arthrography

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    Full Text Available ... the skin is penetrated carries a risk of infection. The chance of infection requiring antibiotic treatment appears to be less than ... Contact Us | FAQ | Privacy | Terms of Use | Links | Site Map Copyright © 2017 Radiological Society of North America, ...

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    Full Text Available ... understanding of the possible charges you will incur. Web page review process: This Web page is reviewed regularly by a physician with expertise ... not responsible for the content contained on the web pages found at these links. About Us | Contact Us | ...

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    Full Text Available ... for immediate assistance. A Word About Minimizing Radiation Exposure Special care is taken during x-ray examinations ... patient's body not being imaged receive minimal radiation exposure. top of page What are the limitations of ...

  6. Arthrography

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    Full Text Available ... claustrophobia. Newer open MRI units provide very high quality images for many types of exams; however, older ... MRI units may not provide this same image quality. Certain types of exams cannot be performed using ...

  7. Arthrography

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    Full Text Available ... a radiologist or other physician. To locate a medical imaging or radiation oncology provider in your community, you can search the ACR- ... with your prescribed procedure with your doctor, the medical facility staff and/or your insurance provider to get a better understanding of the possible ...

  8. Arthrography

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    Full Text Available ... x-ray images were maintained on large film sheets (much like a large photographic negative). Today, most ... accredited facilities database . This website does not provide cost information. The costs for specific medical imaging tests, ...

  9. Arthrography

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    Full Text Available ... atoms return to their usual alignment, they emit energy that varies according to the type of body ... which they come. The MR scanner captures this energy and creates a picture of the tissues scanned ...

  10. Arthrography

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    Full Text Available ... they emit energy that varies according to the type of body tissue from which they come. The ... information you were looking for? Yes No Please type your comment or suggestion into the following text ...

  11. Arthrography

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    Full Text Available ... bone absorbs much of the radiation while soft tissue, such as muscle, fat and organs, allow more of the x-rays to pass through them. As a result, bones appear white on the x-ray, soft tissue shows up in shades of gray and air ...

  12. Arthrography

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    Full Text Available ... and especially lodged in the eyes are particularly important. Dyes used in tattoos may contain iron and ... you, notify the radiologist or technologist. It is important that you remain perfectly still while the images ...

  13. Arthrography

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    Full Text Available ... the scan, possibly causing blindness. Dyes used in tattoos may contain iron and could heat up during ... the area. After the local anesthetic has taken effect, a longer needle is then inserted into the ...

  14. Arthrography

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    Full Text Available ... a contrast material into the joint. The contrast material used for MR evaluation is different from that used for x-ray; it contains gadolinium, which affects the local magnetic field within the ... the contrast material outlines the structures within the joint, such as ...

  15. Arthrography

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    Full Text Available ... ionizing radiation. Instead, radiofrequency pulses re-align hydrogen atoms that naturally exist within the body while you ... chemical changes in the tissues. As the hydrogen atoms return to their usual alignment, they emit different ...

  16. Arthrography

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    Full Text Available ... See the Safety page for more information about pregnancy and x-rays. Though MRI does not use ionizing radiation, women should still inform their physician and technologist if ...

  17. Arthrography

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    Full Text Available ... allowing the radiologist to assess the anatomy and function of the joint. Although the injection is typically ... images help physicians evaluate alterations in structure and function of a joint and help to determine the ...

  18. Arthrography

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    Full Text Available ... of the radiation while soft tissue, such as muscle, fat and organs, allow more of the x- ... follow-up exam is done because a potential abnormality needs further evaluation with additional views or a ...

  19. Arthrography

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    Full Text Available ... Some conditions, such as severe kidney disease, may prevent you from being given MRI or CT arthrogram ... injection. If you have not been sedated, no recovery period is necessary. You may resume your usual ...

  20. Arthrography

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    Full Text Available ... ear) implant some types of clips used for brain aneurysms some types of metal coils placed within ... may distort images of the facial area or brain, so you should let the radiologist know about ...

  1. Arthrography

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    Full Text Available ... allergy to iodine or x-ray contrast material, drugs, food, or environmental agents. However, the contrast material ... are not limited to: artificial heart valves implanted drug infusion ports artificial limbs or metallic joint prostheses ...

  2. Arthrography

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    Full Text Available ... MRI scanners are air-conditioned and well-lit. Music may be played through the headphones to help ... from the contrast material, including nausea, headache and pain at the site of injection. Similarly, patients are ...

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    Full Text Available ... magnetic field of the MRI unit, metal and electronic items are not allowed in the exam room. ... tell the technologist if you have medical or electronic devices in your body. These objects may interfere ...

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    Full Text Available ... it contains gadolinium, which affects the local magnetic field within the joint and appears on the MR ... images are produced. MRI uses a powerful magnetic field, radiofrequency pulses and a computer to produce detailed ...

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    Full Text Available ... ray examination. X-rays usually have no side effects in the typical diagnostic range for this exam. Exams involving MR imaging: MRI is a noninvasive imaging technique that does not involve exposure to ionizing radiation. MRI enables the discovery of abnormalities that might ...

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    Full Text Available ... x-ray may be taken to detect and identify any metal objects. In general, metal objects used in orthopedic surgery pose no risk during MRI. However, a recently placed artificial joint ...

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    Full Text Available ... evaluate and diagnose joint conditions and unexplained pain. It is very effective at detecting disease within the ligaments, tendons and cartilage. It may be indirect, where contrast material is injected ...

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  20. Comparison study of indirect MR arthrography and direct MR arthrography of the shoulder

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    Jung, Jee Young; Yoon, Young Cheol [Sungkyunkwan University, Department of Radiology, Samsung Medical Center, School of Medicine, Seoul (Korea); Yi, Sang-Kyu [Sungkyunkwan University, Department of Radiology, Samsung Medical Center, School of Medicine, Seoul (Korea); Sekye Radiologic Clinic, Daejeon (Korea); Yoo, Jaechul [Sungkyunkwan University, Department of Orthopedic Surgery, School of Medicine, Seoul (Korea); Choe, Bong-Keun [Kyung Hee University, Department of Preventive Medicine, School of Medicine, Seoul (Korea)

    2009-07-15

    To compare the diagnostic value of indirect magnetic resonance arthrography (I-MRA) with that of direct MR arthrography (D-MRA) for labral tears, rotator cuff tears, and long head of biceps tendon (LHBT) tears using a 3-T MR unit. Institutional review board approval was given; written informed consent was obtained from all patients. From November 2005 to June 2006, 19 patients (eight men and 11 women; mean age, 51 years) who had undergone both I-MRA and D-MRA underwent arthroscopic surgery. Both methods were performed in fat-saturated axial, coronal oblique, and sagittal oblique T1-weighted sequences, as well as axial and coronal oblique T2-weighted sequences. Two radiologists independently and retrospectively evaluated two sets of MRA for the diagnosis of superior and anterior labral tears, subscapularis tendon (SSC), and supraspinatus-infraspinatus tendon (SSP-ISP) tears, and LHBT tears. With the arthroscopic finding as a gold standard, we analyzed statistical differences of sensitivities and specificities between two sets of MRA and inter-observer agreement was evaluated using the kappa value. The sensitivity and specificity of I-MRA and D-MRA for reader 1 were 79/80% and 71/80%, respectively, for superior labral tears; 100/100% and 100/100%, respectively, for anterior labral tears; 64/75% and 64/100%, respectively, for SSC tears; 100/86% and 100/100%, respectively, for SSP-ISP tears; and 67/100% and 78/100%, respectively, for LHBT tears. Those of I-MRA and D-MRA for reader 2 were 86/80% and 71/100%, respectively, for superior labral tears; 100/83% and 100/100%, respectively, for anterior labral tears; 64/88% and 82/100%, respectively, for SSC tears; 92/86% and 100/100%, respectively, for SSP-ISP tears; and 78/90% and 89/100%, respectively, for LHBT tears. No significant differences were found between the methods. Inter-observer agreements were higher than moderate ({kappa} > 0.41) with both methods. Based on a relatively small number of patients, no significant

  1. Dual joint space arthrography in temporomandibular joint disorders: Comparison with single inferior joint space arthrography

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    Choi, Hyung Sik; Chang, Duk Soo; Lee, Kyung Soo; Kim, Woo Sun; Sung, Jung Ho; Jun, Young Hwan [Capital Armed Forces General Hospital, Seoul (Korea, Republic of)

    1989-02-15

    The temporomandibular joint(TMJ) is really a complex of two synovial space separated by fibrocartilaginous disc. Single inferior joint space arthrography is commonly performed for evaluation of TMJ disorders, which is known to be superior in demonstrating joint dynamics. But it reveals only the inferior surface of the disc. Therefore, dual space arthrography is superior to demonstrate the soft tissue anatomic feature of the joint such as disc position and shape. Authors performed 83 TMJ arthrograms in TMJ problems. Initially, the inferior joint space was done and then the superior space was sequentially contrasted. The follow results were noted: 1. In all cases, dual space arthrography revealed accurate disc shape and positions. 2. Concordant findings between the two techniques: 68 cases (82%). Discordance between the two techniques: 15 cases (18%) 3. Possible causes of discordance between inferior and dual space arthrography. a) Normal varians of anterior recess: 3 cases b) Posterior disc displacement: 4 cases c) Influence of the patient's head position change :4 cases d) False perforation: 2 cases e) Reduction change: 2 cases 4. In 5 cases with anterior displacement, dual space arthrography gave additional findings such as adhesion within the superior space, which could not be evaluated by single inferior space.

  2. Is a single direct MR arthrography series in ABER position as accurate in detecting anteroinferior labroligamentous lesions as conventional MR arthography?

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    Schreinemachers, Saskia A.; Hulst, Victor P.M. van der; Woude, Henk-Jan van der [Onze Lieve Vrouwe Gasthuis, Department of Radiology, Amsterdam (Netherlands); Jaap Willems, W. [Onze Lieve Vrouwe Gasthuis, Orthopaedic Surgery, Amsterdam (Netherlands); Bipat, Shandra [University of Amsterdam, Department of Radiology, Academic Medical Centre, Amsterdam (Netherlands)

    2009-07-15

    The purpose of this study is to retrospectively compare accuracy of single magnetic resonance (MR) arthrography series in Abduction External Rotation (ABER) with conventional MR arthrography for detection and characterisation of anteroinferior labroligamentous lesions, with arthroscopy as reference standard. Inter-observer variability of both protocols was determined. Institutional review board approval was obtained; informed consent was waived. MR arthrograms, including oblique axial fat suppressed T1-weighted images in ABER position and conventional imaging directions of 250 patients (170 men, 80 women; mean age, 36 years), were retrospectively and independently evaluated by three reviewers. Reviewers were blinded to clinical information and arthroscopic results. Labroligamentous lesions were registered in both ABER and MRa. The lesions were sub-classified (Bankart, Perthes, anterior labrum periosteal sleeve avulsion (ALPSA) or lesions not otherwise specified). Inter-observer agreement was assessed by Kappa statistics for all 250 patients. Ninety-two of 250 patients underwent arthroscopy. Sensitivity, specificity and accuracy of ABER versus conventional MR arthrography were calculated and compared using paired McNemar test. Kappa values of the ABER and conventional MR arthrography ranged from 0.44 to 0.56 and 0.44 to 0.62, respectively. According to arthroscopy, 45 of 92 patients had an intact anteroinferior labrum, and in 44 patients, a labroligamentous lesion (eight Bankart, seven Perthes, 29 ALPSA and three lesions not otherwise specified) was diagnosed. There were no statistically significant differences between ABER and conventional MR arthrography regarding sensitivity (85-89%, 89-96%), specificity (82-91%, 84-89%) and overall accuracy (50-62%, 53-63%). The results of a single MR arthrography series in ABER position are comparable with those of conventional MR arthrography for detecting anteroinferior labroligamentous lesions. (orig.)

  3. Fast MR arthrography using VIBE sequences to evaluate the rotator cuff

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    Vandevenne, Jan E. [Ziekenhuizen Oost-Limburg, Department of Radiology, Genk (Belgium); Universitair Ziekenhuis Antwerpen, University of Antwerp, Department of Radiology, Edegem (Belgium); Vanhoenacker, Filip; Parizel, Paul M. [Universitair Ziekenhuis Antwerpen, University of Antwerp, Department of Radiology, Edegem (Belgium); Mahachie John, Jestinah M. [University of Hasselt, Centre for Statistics, Diepenbeek (Belgium); Gelin, Geert [Ziekenhuizen Oost-Limburg, Department of Radiology, Genk (Belgium)

    2009-07-15

    The purpose of this paper was to evaluate if short volumetric interpolated breath-hold examination (VIBE) sequences can be used as a substitute for T1-weighted with fat saturation (T1-FS) sequences when performing magnetic resonance (MR) arthrography to diagnose rotator cuff tears. Eighty-two patients underwent direct MR arthrography of the shoulder joint using VIBE (acquisition time of 13 s) and T1-FS (acquisition time of 5 min) sequences in the axial and paracoronal plane on a 1.0-T MR unit. Two radiologists scored rotator cuff tendons on VIBE and T1-FS images separately as normal, small/large partial thickness and full thickness tears with or without geyser sign. T1-FS sequences were considered the gold standard. Surgical correlation was available in a small sample. Sensitivity, specificity, and positive and negative predictive values of VIBE were greater than 92% for large articular-sided partial thickness and full thickness tears. For detecting fraying and articular-sided small partial thickness tears, these parameters were 55%, 94%, 94%, and 57%, respectively. The simple kappa value was 0.76, and the weighted kappa value was 0.86 for agreement between T1-FS and VIBE scores. All large partial and full thickness tears at surgery were correctly diagnosed using VIBE or T1-FS MR images. Fast MR arthrography of the shoulder joint using VIBE sequences showed good concordance with the classically used T1-FS sequences for the appearance of the rotator cuff, in particular for large articular-sided partial thickness tears and for full thickness tears. Due to its very short acquisition time, VIBE may be especially useful when performing MR arthrography in claustrophobic patients or patients with a painful shoulder. (orig.)

  4. Fast MR arthrography using VIBE sequences to evaluate the rotator cuff.

    Science.gov (United States)

    Vandevenne, Jan E; Vanhoenacker, Filip; Mahachie John, Jestinah M; Gelin, Geert; Parizel, Paul M

    2009-07-01

    The purpose of this paper was to evaluate if short volumetric interpolated breath-hold examination (VIBE) sequences can be used as a substitute for T1-weighted with fat saturation (T1-FS) sequences when performing magnetic resonance (MR) arthrography to diagnose rotator cuff tears. Eighty-two patients underwent direct MR arthrography of the shoulder joint using VIBE (acquisition time of 13 s) and T1-FS (acquisition time of 5 min) sequences in the axial and paracoronal plane on a 1.0-T MR unit. Two radiologists scored rotator cuff tendons on VIBE and T1-FS images separately as normal, small/large partial thickness and full thickness tears with or without geyser sign. T1-FS sequences were considered the gold standard. Surgical correlation was available in a small sample. Sensitivity, specificity, and positive and negative predictive values of VIBE were greater than 92% for large articular-sided partial thickness and full thickness tears. For detecting fraying and articular-sided small partial thickness tears, these parameters were 55%, 94%, 94%, and 57%, respectively. The simple kappa value was 0.76, and the weighted kappa value was 0.86 for agreement between T1-FS and VIBE scores. All large partial and full thickness tears at surgery were correctly diagnosed using VIBE or T1-FS MR images. Fast MR arthrography of the shoulder joint using VIBE sequences showed good concordance with the classically used T1-FS sequences for the appearance of the rotator cuff, in particular for large articular-sided partial thickness tears and for full thickness tears. Due to its very short acquisition time, VIBE may be especially useful when performing MR arthrography in claustrophobic patients or patients with a painful shoulder.

  5. A Simple Technique for Shoulder Arthrography

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    Berna-Serna, J.D.; Redondo, M.V.; Martinez, F.; Reus, M.; Alonso, J.; Parrilla, A.; Campos, P.A. [Virgen de la Arrixaca Univ. Hospital, El Palmar, Murcia (Spain). Dept. of Radiology

    2006-09-15

    Purpose: To present a systematic approach to teaching a technique for arthrography of the shoulder. Using an adhesive marker-plate with radiopaque coordinates, precise sites for puncture can be identified and the need for fluoroscopic guidance obviated. Material and Methods: Forty-six glenohumeral arthrograms were performed in 45 patients; in 1 case involving examination of both shoulders. The stages of the technique are described in detail, as are the fundamental aspects of achieving an effective glenohumeral injection. Pain intensity was measured in all patients using a verbal description scale. Results: Shoulder arthrography was successful in all cases. Average time taken for the procedure was 7 min, with no difference in the respective times required by an experienced radiologist and a resident. The procedure was well tolerated by most patients, with slight discomfort being observed in a very few cases. Conclusion: The arthrographic technique used in this study is simple, safe, rapid, and reproducible, and has the advantage of precise localization of the site for puncture without need for fluoroscopic guidance. The procedure described in this study can be of help in teaching residents and can reduce the learning curve for radiologists with no experience in arthrographic methods. It also reduces the time of exposure to fluoroscopy Keywords: Arthrography, joint, shoulder.

  6. Comparison of three dimensional isotropic and two dimensional conventional indirect MR arthrography for the diagnosis of rotator cuff tears

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    Lee, Ji Hyun; Yoon, Young Cheol; Kwon, Jong Won; Yoo, Jae Chul [Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul (Korea, Republic of); Cha, Jang Kyu [Dept. of Radiology, Soonchunhyang University Bucheon Hospital, Bucheon (Korea, Republic of); Jee, Suk Kyoung [Joeun Madi Hospital, Seoul (Korea, Republic of)

    2014-12-15

    To compare the accuracy between a three-dimensional (3D) indirect isotropic T1-weighted fast spin-echo (FSE) magnetic resonance (MR) arthrography and a conventional two-dimensional (2D) T1-weighted sequences of indirect MR arthrography for diagnosing rotator cuff tears. The study was approved by our Institutional Review Board. In total, 205 patients who had undergone indirect shoulder MR arthrography followed by arthroscopic surgery for 206 shoulders were included in this study. Both conventional 2D T1-weighted FSE sequences and 3D isotropic T1-weighted FSE sequence were performed in all patients. Two radiologists evaluated the images for the presence of full- or partial-thickness tears in the supraspinatus-infraspinatus (SSP-ISP) tendons and tears in the subscapularis (SSC) tendons. Using the arthroscopic findings as the reference standard, the diagnostic performances of both methods were analyzed by the area under the receiver operating characteristic curve (AUC). Arthroscopy confirmed 165 SSP-ISP tendon tears and 103 SSC tendon tears. For diagnosing SSP-ISP tendon tears, the AUC values were 0.964 and 0.989 for the 2D sequences and 3D T1-weighted FSE sequence, respectively, in reader I and 0.947 and 0.963, respectively, in reader II. The AUC values for diagnosing SSC tendon tears were 0.921 and 0.925, respectively, for reader I and 0.856 and 0.860, respectively, for reader II. There was no significant difference between the AUC values of the 2D and 3D sequences in either reader for either type of tear. 3D indirect isotropic MR arthrography with FSE sequence and the conventional 2D arthrography are not significantly different in terms of accuracy for diagnosing rotator cuff tears.

  7. Articular cartilage defect detectability in human knees with MR-arthrography

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    Engel, A. [Orthopaedic Clinic, Univ. of Vienna (Austria); Kramer, J. [MR-Inst., Univ. of Vienna (Austria); Stiglbauer, R. [MR-Inst., Univ. of Vienna (Austria); Hajek, P.C. [MR-Inst., Univ. of Vienna (Austria); Imhof, H. [MR-Inst., Univ. of Vienna (Austria)

    1993-04-01

    One hundred and thirteen knee joints were examined, of which 48 showed damage of the hyaline cartilage in one or more locations. For the evaluation of the magnetic resonance (MR) arthrographic images we used the macroscopic staging according to Outerbridge, the defect staging according to Bauer, as well as a new MR-arthrographic staging. The results of the evaluation were compared with the surgical findings in 61 knee joints. This revealed a sensitivity of 86 %, a specificity of 100 % and accuracy of 90 %. All lesions that could not be classified on MR-arthrography were of stage-I chondromalacia. (orig.)

  8. Arthrography in sport injuries of the knee joint

    Energy Technology Data Exchange (ETDEWEB)

    Schaefer, H.

    1983-09-01

    The arthrography is one of the most important diagnostic methods of sport injuries of the knee joint. The examination must give an exact information to the surgeon; a good technique and standard X-rays are an absolute postulate. The submitted examinations are based on 6687 arthrographies during a period of 5 years. The arthrography should not be carried out before the acute symptomatology has ceased, usually after an interval of 2-3 weeks. Most frequent are the meniscus injuries by rotary traumas of the knee-joint. Football as the most popular sport is responsible for more than 50% of the injuries, followed by skiing, handball and jogging.

  9. A Severe Case of Arthrographis kalrae Keratomycosis

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    Siti Roszilawati Ramli

    2013-01-01

    Full Text Available A 52-year-old man with diabetes developed a unilateral central corneal ulcer after accidental foreign body inoculation. He complained of pain and loss of visual acuity in the injured eye, which displayed redness and edema and eventually discharged pus. A corneal scraping from the left eye orbit revealed fungal elements, and cultures of the material grew a fungus. The isolate was identified as Arthrographis kalrae based on gross and microscopic morphologies. The patient received amphotericin B intravenously and itraconazole orally. The wound healed following surgical intervention, but the patient lost the use of his left eye.

  10. Multidetector spiral CT arthrography of the shoulder. Clinical applications and limits, with MR arthrography and arthroscopic correlations.

    Science.gov (United States)

    Lecouvet, Frédéric E; Simoni, Paolo; Koutaïssoff, Sophie; Vande Berg, Bruno C; Malghem, Jacques; Dubuc, Jean-Emile

    2008-10-01

    Although MR imaging and MR arthrography are the first choice modalities for shoulder imaging, CT arthrography (CTA) may be used successfully to address many clinical questions. The advent of submillimeter multiple detector CT technology and subsequent excellent three-plane resolution has considerably increased the quality of CTA examinations and has propelled this technique to the forefront in a growing number of indications. The combined use of iodinated contrast material for fluoroscopic confirmation of the articular position of the needle before injection of gadolinium chelates for MR arthrography offers the unique opportunity to compare CTA and MRA findings in carefully selected cases. This paper illustrates capabilities and limits of CTA for the study of rotator cuff tears, shoulder instability, cartilage lesions, anatomical variants and abnormalities of the glenoid labrum, with correlations to MR arthrography and surgical findings.

  11. MR arthrography of the shoulder: Do we need local anesthesia?

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    Spick, Claudio, E-mail: claudio.spick@meduniwien.ac.at [Department of Biomedical Imaging and Image-guided Therapy, Medical University of Vienna (AKH), Waehringer-Guertel 18-20, 1090 Vienna (Austria); Szolar, Dieter H.M.; Reittner, Pia; Preidler, Klaus W.; Tillich, Manfred [Diagnostikum Graz-Südwest, Weblinger Guertel 25, 8054 Graz (Austria)

    2014-06-15

    Purpose: To assess pain intensity with and without subcutaneous local anesthesia prior to intraarticular administration of contrast medium for magnetic resonance arthrography (MRa) of the shoulder. Materials and methods: This single-center study was conducted after an IRB waiver of authorization, between January 2010 and December 2012. All patients provided written, informed consent for the procedure. Our prospectively populated institutional database was searched, based on our inclusion criteria. There were 249 outpatients (178 men and 71 women; mean age, 44.4 years ± 14.6; range, 15–79) who underwent MRa and were enrolled in this study. Patients were excluded if they had received surgery of the shoulder before MRa, had undergone repeated MRa of the same shoulder, and/or had undergone MRa of both shoulders on the same day. Patients were randomly assigned into one of three groups. Patients in group A (n = 61) received skin infiltration with local anesthesia. Patients in control group B (n = 92) and group C (n = 96) did not receive local anesthesia. Pain levels were immediately assessed after the injection for MRa using a horizontal visual analog scale (VAS) that ranged from 0 to 10. To compare the pain scores of the three groups for male and female patients, a two-way analysis of variance was used. A p-value equal to or less than 0.05 was considered to indicate a significant result. Results: Patients who received local anesthesia (group A) showed a mean pain level on the VAS of 2.6 ± 2.3. In patients who did not receive local anesthetics (groups B and C), a mean pain level on the VAS of 2.6 ± 2.2 and 2.7 ± 2.4 were detected, respectively. Between the three groups, no statistically significant difference in pain intensity was detected (p = .960). There were significant differences in subjective pain perception between men and women (p = .009). Moreover, the sex difference in all three groups was equal (p = .934). Conclusion: Local anesthesia is not required to

  12. MDCT arthrography of the wrist: Diagnostic accuracy and indications

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    De Filippo, Massimo [Department of Clinical Sciences, Section of Radiological Sciences, University of Parma, Parma Hospital, Via Gramsci, 14, 43100 Parma (Italy)], E-mail: massimo.defilippo@unipr.it; Pogliacomi, Francesco [Orthopaedics, Traumatology and Functional Rehabilitation Unit, Department of Surgical Sciences, University of Parma, Parma Hospital, Via Gramsci 14, 43100 Parma (Italy); Bertellini, Annalisa [Department of Clinical Sciences, Section of Radiological Sciences, University of Parma, Parma Hospital, Via Gramsci, 14, 43100 Parma (Italy); Araoz, Philip A. [Department of Radiology, Division of Biostatistics, Mayo Clinic, 200 First St SW, Rochester, MN 55905 (United States); Averna, Raffaele; Sverzellati, Nicola; Ingegnoli, Anna [Department of Clinical Sciences, Section of Radiological Sciences, University of Parma, Parma Hospital, Via Gramsci, 14, 43100 Parma (Italy); Corradi, Maurizio; Costantino, Cosimo [Orthopaedics, Traumatology and Functional Rehabilitation Unit, Department of Surgical Sciences, University of Parma, Parma Hospital, Via Gramsci 14, 43100 Parma (Italy); Zompatori, Maurizio [Department of Radiological and Histopathological Sciences, Policlinic S.Orsola-Malpighi, University of Bologna, Via Massarenti 9, 40138 Bologna (Italy)

    2010-04-15

    Purpose: To evaluate the diagnostic accuracy and indications of arthrography with Multidetector Computed Tomography (arthro-MDCT) of the wrist in patients with absolute or relative contraindications to magnetic resonance imaging (MRI) studies and in patients with periarticular metal implants using diagnostic arthroscopy as the gold standard. Materials and methods: After intra-articular injection of iodixanol and volumetric acquisition, 43 wrists in patients of both genders (18 females, 25 males, age range 32-60 years) were examined with a 16-detector-row CT scanner. Fifteen patients had prior wrist surgery. The patients had arthralgia, degenerative and traumatic arthropathies as well as limited range of motion, but no radiologically detected fractures. All examinations were interpreted by two experienced musculoskeletal radiologists. The findings were compared with arthroscopic findings carried out within 28 days of the CT study. Results: In non-operated and operated wrists the comparison between arthro-MDCT and arthroscopy showed sensitivity, specificity and accuracy ranging between 92% and 94% for triangular fibrocartilage complex (TFCC), between 80% and 100% for intrinsic ligaments located within the proximal carpal compartment, and between 94% and 100% for articular cartilage. Inter-observer agreement between two radiologists, in the evaluation of all types of lesions, was almost perfect (k = 0.96) and statistically significant (p < 0.05). Conclusions: Arthro-MDCT of the wrist provides an accurate diagnosis to identify chondral, fibrocartilaginous and intra-articular ligament lesions in patients who cannot be evaluated by MRI, and in post-surgical patients.

  13. Potential Utility of a Combined Approach with US and MR Arthrography to Image Medial Elbow Pain in Baseball Players.

    Science.gov (United States)

    Roedl, Johannes B; Gonzalez, Felix M; Zoga, Adam C; Morrison, William B; Nevalainen, Mika T; Ciccotti, Michael G; Nazarian, Levon N

    2016-06-01

    Purpose To evaluate a combined imaging approach with both ultrasonography (US; conventional US and valgus stress US) and magnetic resonance (MR) arthrography in baseball players with medial elbow pain. Materials and Methods Institutional review board approval was obtained and the requirement for informed consent was waived. The study is compliant with HIPAA. Baseball players with medial elbow pain underwent US in addition to MR arthrography. Findings were assessed with each modality alone and both combined in this retrospective investigation. For the evaluation of ulnar collateral ligament (UCL) tears with stress US, the interval gapping of the medial elbow joint was measured between rest and valgus stress both at the injured and at the uninjured (contralateral) elbow. Surgical or arthroscopic correlation was available as the so-called gold standard. McNemar tests compared the accuracies of the imaging modalities. Results In this study, 144 baseball players had 191 findings of medial elbow pain, including 53 UCL tears. With stress US, joint gapping at the injured elbow greater than 1.0 mm compared with the contralateral elbow yielded a sensitivity, specificity, and accuracy of 96%, 81%, and 87%, respectively, for diagnosing UCL tears. With MR arthrography, the sensitivity, specificity, and accuracy for UCL tears were 81%, 91%, and 88%, respectively, and increased to 96% (P = .013, McNemar test), 99% (P = .023), and 98% (P < .001), respectively, when combined with US to a dual modality MR and US approach. For 31 patients with ulnar neuritis, the sensitivity, specificity, and accuracy increased from 74%, 92%, and 88%, respectively, with MR arthrography alone to 90% (P = .07, McNemar test), 100% (P < .001), and 98% (P < .001) combined with US. For the 59 myotendinous and the 48 osteochondral diagnoses, the sensitivity, specificity, and accuracy with MR arthrography alone were 93%, 93%, and 93%, and 94%, 98%, and 97%, respectively, with no additional diagnostic value

  14. Usefulness of MR arthrography of the hip with leg traction in the evaluation of ligamentum teres injuries

    Energy Technology Data Exchange (ETDEWEB)

    Cerezal, Luis; Fernandez-Hernando, Moises [Department of Radiology, Diagnostico Medico Cantabria, Santander, Cantabria (Spain); Perez Carro, Luis [Learnig Trauma Med. Centro de Consultas Medicas CCM, Orthopedic Surgery department, Santander (Spain); Llorca, Javier [University of Cantabria - IDIVAL, Santander (Spain); CIBER Epidemiology and Public Health, Santander (Spain); Llopis, Eva [Alzira Hospital, Department of Radiology, Valencia (Spain); Montero, Juan Antonio [Cantabria University, Anatomy and Cell Biology, Santander (Spain); Canga, Ana [Cantabria University, Anatomy and Cell Biology, Santander (Spain); Department of Radiology Marques de Valdecilla University Hospital, Santander, Cantabria (Spain)

    2015-11-15

    To retrospectively evaluate the diagnostic accuracy of magnetic resonance (MR) arthrography of the hip with leg traction in the evaluation of ligamentum teres lesions and to evaluate whether there is increased articular distraction, possibly indicating secondary instability, in hips with ligamentum teres injuries. Institutional review board approval and informed consent were obtained for this retrospective study. MR arthrograms of the hip with leg traction of 184 consecutive patients, including 108 men (mean age, 32.6 years; range, 19-53 years) and 76 women (mean age, 38.5 years; range, 18-56 years), who underwent hip arthroscopy were assessed for the presence of ligamentum teres lesions. The MR arthrographic findings were independently assessed by two radiologists who were blinded to the arthroscopic results. The inclusion criteria stipulated no previous surgery, arthroscopy within 1 month after MR arthrography, and availability of a detailed surgical report with ligamentum teres findings. The arthroscopy findings served as the reference standard. Sensitivity, specificity, accuracy, and K statistics for interobserver and intraobserver agreement were calculated. At arthroscopy, 32 ligamentum teres injuries were found. The ligamentum teres was normal in 152 (82.6 %) patients and had suffered low-grade partial tears in 15 (8.1 %) patients, high-grade partial tears in 10 (5.4 %) patients, and complete ruptures in 7 (3.8 %) patients. MR arthrography with axial traction demonstrated moderate sensitivity and high specificity for both low-grade (62/93 %) and high-grade (66/96 %) partial tears. Grouping low- and high-grade partial tears increased the diagnostic performance of MR arthrography, yielding a sensitivity of 87 % and a specificity of 95 %. For complete ligamentum teres tears, MR arthrography with leg traction demonstrated high sensitivity (92 %) and specificity (98 %). Articular distraction was significantly increased in patients with complete ruptures of the

  15. MR arthrography of the shoulder: possible indications for clinical use; Einsatzmoeglichkeiten der MR-Arthrographie bei Erkrankungen des Schultergelenkes

    Energy Technology Data Exchange (ETDEWEB)

    Kreitner, K.F. [Mainz Univ. (Germany). Klinik mit Poliklinik fuer Radiologie; Grebe, P. [Mainz Univ. (Germany). Klinik mit Poliklinik fuer Radiologie; Kersjes, W. [Mainz Univ. (Germany). Klinik mit Poliklinik fuer Radiologie; Runkel, M. [Mainz Univ. (Germany). Klinik fuer Unfallchirurgie; Kirschner, P. [Elisabeth-Hospital, Mainz (Germany). Abt. fuer Unfall- und Wiederherstellungschirurgie St. Vincenz; Schild, H.H. [Mainz Univ. (Germany). Klinik mit Poliklinik fuer Radiologie

    1994-02-01

    In a prospective study possible indications for MR arthrography of the shoulder were evaluated. 37 patients were examined before and after intraarticular administration of a 2-mmolar solution of Gd-DTPA. MR arthrography was performed if there was no joint effusion and/or an uncertain finding concerning the rotator cuff or the capsulolabral complex on plain MR images. MR arthrography leads to a better demonstration of labrum pathology in 11/22 patients and to a superior delineation of the capsuloligamentous apparatus in 20/22 cases. In 9/15 patients with impingement lesions MR arthrography allowed a differentiation of severe tendinitis from partial and small full-thickness tears of the rotator cuff. MR arthrography of the shoulder joint enhances the accuracy of MR in case of an uncertain finding on plain MR images. (orig.) [Deutsch] In einer prospektiven Studie sollten Einsatzmoeglichkeiten der MR-Arthrographie bei Erkrankungen des Schultergelenkes herausgearbeitet werden. 37 Patienten wurden sowohl nativ als auch nach intraartikulaerer Gabe einer 2mmolaren Gd-DTPA-Loesung untersucht. Voraussetzungen fuer die KM-Gabe waren ein fehlender Gelenkerguss und/oder ein unklarer Befund des Labrum-Kapsel-Komplexes oder der Rotatorenmanschette in der Nativuntersuchung. Durch die MR-Arthrographie wurde bei 11/22 Patienten eine verbesserte Darstellung der Labrumpathologie erzielt; in 20/22 Faellen ergabe sich eine zuverlaessige Beurteilung der Gelenkkapsel. Bei 9/15 Patienten mit Erkrankungen der Rotatorenmanschette konnten Tendinitiden von partiellen und kleinen kompletten Rotatorenmanschettenrupturen sicher differenziert werden. Die MR-Arthrographie des Schultergelenkes fuehrt bei nicht eindeutigen Befunden in der Nativuntersuchung zu einer verbesserten Treffsicherheit der MR-Diagnostik. (orig.)

  16. Biceps tendon disorders: ultrasound, MR imaging and MR arthrography; Bizepsprobleme: Ultraschall, Magnetresonanztomographie und MR-Arthrographie

    Energy Technology Data Exchange (ETDEWEB)

    Zanetti, M.; Pfirrmann, C.W.A. [Radiologie, Uniklinik Balgrist Zuerich (Switzerland)

    2004-06-01

    Ultrasound and MR imaging are competitive imaging modalities for the diagnosis of pathologic conditions of the biceps tendon. MR imaging has substantial advantages over ultrasound because biceps tendon lesions are most commonly located in the proximal part where lesions are hidden under the acromion for ultrasound assessment. The value of MR arthrography is substantiated by the capability to assess associated diagnoses which are otherwise difficult to assess. Associated diagnoses include full- and partial thickness tears of supraspinatus and subscapularis tendons, pulley lesions, and adhesive capsulitis (frozen shoulder). Moreover, MR arthrography is the method of choice for the assessment of superior labral anterior posterior (SLAP) lesions. (orig.) [German] Der nachfolgende Uebersichtsartikel beschreibt die haeufigsten Bizepsprobleme der Schulter, wie sie in einem orthopaedisch ausgerichteten Radiologieinstitut gesehen werden. Ultraschall und MRT sind geeignet zur Evaluation von Bizepsproblemen. Der Ultraschall weist Vorteile in der dynamischen Untersuchung auf, vermag aber die proximal gelegenen Laesionen nicht zuverlaessig zu erfassen. Die MRT liefert Zusatzinformationen zu den haeufig assoziierten Begleitpathologien an der Rotatorenmanschette und an den Kapsel- und Ligamentstrukturen. Die MR-Arthrographie ist die Methode der Wahl zur Diagnose der SLAP-(superior-labral-anterior-posterior-)Laesion. (orig.)

  17. Giant electric field control of magnetism and narrow ferromagnetic resonance linewidth in FeCoSiB/Si/SiO2/PMN-PT multiferroic heterostructures

    Science.gov (United States)

    Gao, Y.; Wang, X.; Xie, L.; Hu, Z.; Lin, H.; Zhou, Z.; Nan, T.; Yang, X.; Howe, B. M.; Jones, J. G.; Brown, G. J.; Sun, N. X.

    2016-06-01

    It has been challenging to achieve combined strong magnetoelectric coupling and narrow ferromagnetic resonance (FMR) linewidth in multiferroic heterostructures. Electric field induced large effective field of 175 Oe and narrow FMR linewidth of 40 Oe were observed in FeCoSiB/Si/SiO2/PMN-PT heterostructures with substrate clamping effect minimized through removing the Si substrate. As a comparison, FeCoSiB/PMN-PT heterostructures with FeCoSiB film directly deposited on PMN-PT showed a comparable voltage induced effective magnetic field but a significantly larger FMR linewidth of 283 Oe. These multiferroic heterostructures exhibiting combined giant magnetoelectric coupling and narrow ferromagnetic resonance linewidth offer great opportunities for integrated voltage tunable RF magnetic devices.

  18. Augmented reality visualization with use of image overlay technology for MR imaging-guided interventions: assessment of performance in cadaveric shoulder and hip arthrography at 1.5 T.

    Science.gov (United States)

    Fritz, Jan; U-Thainual, Paweena; Ungi, Tamas; Flammang, Aaron J; Fichtinger, Gabor; Iordachita, Iulian I; Carrino, John A

    2012-10-01

    To prospectively assess overlay technology in providing accurate and efficient targeting for magnetic resonance (MR) imaging-guided shoulder and hip joint arthrography. A prototype augmented reality image overlay system was used in conjunction with a clinical 1.5-T MR imager. A total of 24 shoulder joint and 24 hip joint injections were planned in 12 human cadavers. Two operators (A and B) participated, each performing procedures on different cadavers using image overlay guidance. MR imaging was used to confirm needle positions, monitor injections, and perform MR arthrography. Accuracy was assessed according to the rate of needle adjustment, target error, and whether the injection was intraarticular. Efficiency was assessed according to arthrography procedural time. Operator differences were assessed with comparison of accuracy and procedure times between the operators. Mann-Whitney U test and Fisher exact test were used to assess group differences. Forty-five arthrography procedures (23 shoulders, 22 hips) were performed. Three joints had prostheses and were excluded. Operator A performed 12 shoulder and 12 hip injections. Operator B performed 11 shoulder and 10 hip injections. Needle adjustment rate was 13% (six of 45; one for operator A and five for operator B). Target error was 3.1 mm±1.2 (standard deviation) (operator A, 2.9 mm±1.4; operator B, 3.5 mm±0.9). Intraarticular injection rate was 100% (45 of 45). The average arthrography time was 14 minutes (range, 6-27 minutes; 12 minutes [range, 6-25 minutes] for operator A and 16 minutes [range, 6-27 min] for operator B). Operator differences were not significant with regard to needle adjustment rate (P=.08), target error (P=.07), intraarticular injection rate (P>.99), and arthrography time (P=.22). Image overlay technology provides accurate and efficient MR guidance for successful shoulder and hip arthrography in human cadavers. © RSNA, 2012.

  19. Blast wave fits with resonances to $p_t$ spectra from nuclear collisions at the LHC

    CERN Document Server

    Melo, Ivan

    2015-01-01

    We report our results for the freeze-out temperature and transverse flow profile obtained from fits to hadronic spectra measured by the ALICE collaboration. The influence of resonance decays is important and cannot be simply accounted for without the inclusion of their decays into the fits.

  20. Assessment of the rotator cable in various rotator cuff conditions using indirect MR arthrography.

    Science.gov (United States)

    Choo, Hye Jung; Lee, Sun Joo; Kim, Dong Wook; Park, Young-Mi; Kim, Jung-Han

    2014-11-01

    The rotator cable is an important structure providing stress shield to the rotator cuff, similar to the mechanism of suspension bridge. To evaluate the visibility and appearance of the rotator cable in various conditions of the rotator cuff, using indirect magnetic resonance (MR) arthrography. Indirect MR arthrography images from 27 patients (age range, 20-63 years) with normal rotator cuffs, and 47 (age range, 20-73 years) with tendinosis, 32 (age range, 49-71 years) with partial-thickness tears, and 55 (age range, 44-75 years) with full-thickness tears in the supraspinatus and infraspinatus tendons (SST-ISTs) were included in this study. In these various rotator cuff conditions, the visibility and appearance (thickness and width) of the rotator cable and the relationships between the rotator cable appearance, rotator cuff tear size, rotator cuff thickness, and patient's age were assessed. On the sagittal MR images, all rotator cables were visible in the normal rotator cuffs and tendinosis/partial-thickness tears of SST-ISTs. In the order of normal cuff, tendinosis, partial-thickness tear, and full-thickness tear of SST-ISTs, the rotator cable tended to become thicker (1.07, 1.27, 1.32, and 1.59 mm, respectively) and narrower (12.1, 10.68, 10.90, and 8.55 mm, respectively). The thickness of the rotator cable was significantly positively correlated with the rotator cuff thickness in the normal rotator cuffs (coefficient, 0.49; P = 0.010) and tendinosis of SST-ISTs (coefficient, 0.53; P < 0.001), but was not correlated with patients' age. On sagittal plane of indirect MR arthrography, most rotator cables were visible. The appearance of the rotator cable changed according to the rotator cuff condition. © The Foundation Acta Radiologica 2013 Reprints and permissions: sagepub.co.uk/journalsPermissions.nav.

  1. Pre-clinical functional magnetic resonance imaging. Pt. II. The heart

    Energy Technology Data Exchange (ETDEWEB)

    Messner, Nadja M.; Zoellner, Frank G.; Kalayciyan, Raffi; Schad, Lothar R. [Heidelberg Univ., Mannheim (Germany). Computer Assisted Clinical Medicine

    2014-07-01

    One third of all deaths worldwide in 2008 were caused by cardiovascular diseases (CVD), and the incidence of CVD related deaths rises ever more. Thus, improved imaging techniques and modalities are needed for the evaluation of cardiac morphology and function. Cardiac magnetic resonance imaging (CMRI) is a minimally invasive technique that is increasingly important due to its high spatial and temporal resolution, its high soft tissue contrast and its ability of functional and quantitative imaging. It is widely accepted as the gold standard of cardiac functional analysis. In the short period of small animal MRI, remarkable progress has been achieved concerning new, fast imaging schemes as well as purpose-built equipment. Dedicated small animal scanners allow for tapping the full potential of recently developed animal models of cardiac disease. In this paper, we review state-of-the-art cardiac magnetic resonance imaging techniques and applications in small animals at ultra-high fields (UHF).

  2. Diagnosis of chondromalacia patellae using CT arthrography

    Energy Technology Data Exchange (ETDEWEB)

    Reiser, M.; Karpf, P.M.; Bernett, P.

    1982-08-01

    Using anatomical specimens for experimental investigations, the physical-technical prerequisites for proper demonstration of the femoro-patellar articulation were determined and the following results obtained: hyaline cartilage possesses an attenuation value of 25-35 HU; artificial lesions from 1 mm. deep and 2 mm. wide minimum can be visualized; the use of positive contrast medium is best suited for demonstration of chondral lesions. In clinical practice we found that the various stages of cartilaginous degeneration peculiar to chondromalacia (Fruend I to III) are clearly demonstrated by CT arthrography. In CT the predisposing changes in the morphology of the patella and the femoro-patellar articulation are more precisely defined than in conventional tangential roentgenograms. In 69 cases the CT arthrographic findings could be verified at operation. However, the extent and severity of the lesions was, at times, underestimated.

  3. A ressonância magnética e a artrorressonância magnética na lesão labral e condral do quadril: comparação com achados na artroscopia Magnetic resonance imaging and magnetic resonance arthrography in labral and chondral lesion of the hip: comparison with arthroscopy findings

    Directory of Open Access Journals (Sweden)

    Marcos Emilio Kuschnaroff Contreras

    2008-06-01

    Full Text Available OBJETIVO: Estudar a sensibilidade da ressonância magnética (RM e da artrorressonância magnética (artro RM para o diagnóstico das lesões do lábio acetabular e das lesões de cartilagem do quadril. MÉTODOS: Foram incluídos 90 pacientes (90 quadris, submetidos à videoartroscopia do quadril, no período entre maio de 2004 e julho de 2007, na Ultralitho Centro Médico e no Hospital Governador Celso Ramos, ambos em Florianópolis, Santa Catarina. Dos 90 pacientes, 25 (27,7% realizaram RM, sem contraste, 54 (60% realizaram artro RM e 11 (12,22% realizaram os dois exames. Nos pacientes submetidos a artro RM, foi introduzido junto com o contraste um anestésico local (bupivacaína 0,5%, ou ropivacaína 1%, sem adrenalina. Em todos os casos, verificou-se a presença de lesão do lábio acetabular e de lesão condral durante a videoartroscopia. RESULTADOS: Os autores encontraram maior sensibilidade para o diagnostico de lesão do lábio acetabular com a artro RM (96,9%, do que com RM (86,1%, sendo esta diferença estatisticamente significante. Quanto ao diagnóstico de lesão da cartilagem do quadril, a sensibilidade da artro RM foi de 78,4% e a da RM foi de 55,5%, encontrando-se também diferença estatisticamente significante. Houve maior percentagem de falso-negativo na RM, tanto para o diagnostico de lesão labral quanto condral. Não foi encontrado nenhum caso de falso-positivo nesta série. A introdução de anestésico local para a realização de artro RM mostrou alivio da dor em 56,9%dos casos. CONCLUSÃO: Os autores concluíram que a artro RM apresentou maior sensibilidade de diagnóstico que a RM para lesões do lábio acetabular e da cartilagem do quadril. A indiferença ou a piora da dor, após a introdução de anestésico local na artro RM, não foi considerada como fator preditivo para lesões intra-articulares.OBJECTIVE: To study the sensitivity of magnetic resonance imaging (MRI and magnetic resonance arthrography (MRA for the

  4. Pre-clinical functional magnetic resonance imaging. Pt. I. The kidney

    Energy Technology Data Exchange (ETDEWEB)

    Zoellner, Frank G.; Kalayciyan, Raffi; Chacon-Caldera, Jorge; Zimmer, Fabian; Schad, Lothar R. [Heidelberg Univ., Mannheim (Germany). Computer Assisted Clinical Medicine

    2014-07-01

    The prevalence of chronic kidney disease (CKD) is increasing worldwide. In Europe alone, at least 8% of the population currently has some degree of CKD. CKD is associated with serious comorbidity, reduced life expectancy, and high economic costs; hence, the early detection and adequate treatment of kidney disease is important. Pre-clinical research can not only give insights into the mechanisms of the various kidney diseases but it also allows for investigating the outcome of new drugs developed to treat kidney disease. Functional magnetic resonance imaging provides non-invasive access to tissue and organ function in animal models. Advantages over classical animal research approaches are numerous: the same animal might be repeatedly imaged to investigate a progress or a treatment of disease over time. This has also a direct impact on animal welfare and the refinement of classical animal experiments as the number of animals in the studies might be reduced. In this paper, we review current state of the art in functional magnetic resonance imaging with a focus on pre-clinical kidney imaging.

  5. Comparison of three-dimensional isotropic and two-dimensional conventional indirect MR arthrography for the diagnosis of rotator cuff tears.

    Science.gov (United States)

    Lee, Ji Hyun; Yoon, Young Cheol; Jee, Sukkyung; Kwon, Jong Won; Cha, Jang Gyu; Yoo, Jae Chul

    2014-01-01

    To compare the accuracy between a three-dimensional (3D) indirect isotropic T1-weighted fast spin-echo (FSE) magnetic resonance (MR) arthrography and a conventional two-dimensional (2D) T1-weighted sequences of indirect MR arthrography for diagnosing rotator cuff tears. The study was approved by our Institutional Review Board. In total, 205 patients who had undergone indirect shoulder MR arthrography followed by arthroscopic surgery for 206 shoulders were included in this study. Both conventional 2D T1-weighted FSE sequences and 3D isotropic T1-weighted FSE sequence were performed in all patients. Two radiologists evaluated the images for the presence of full- or partial-thickness tears in the supraspinatus-infraspinatus (SSP-ISP) tendons and tears in the subscapularis (SSC) tendons. Using the arthroscopic findings as the reference standard, the diagnostic performances of both methods were analyzed by the area under the receiver operating characteristic curve (AUC). Arthroscopy confirmed 165 SSP-ISP tendon tears and 103 SSC tendon tears. For diagnosing SSP-ISP tendon tears, the AUC values were 0.964 and 0.989 for the 2D sequences and 3D T1-weighted FSE sequence, respectively, in reader I and 0.947 and 0.963, respectively, in reader II. The AUC values for diagnosing SSC tendon tears were 0.921 and 0.925, respectively, for reader I and 0.856 and 0.860, respectively, for reader II. There was no significant difference between the AUC values of the 2D and 3D sequences in either reader for either type of tear. 3D indirect isotropic MR arthrography with FSE sequence and the conventional 2D arthrography are not significantly different in terms of accuracy for diagnosing rotator cuff tears.

  6. Comparison of Three-Dimensional Isotropic and Two-Dimensional Conventional Indirect MR Arthrography for the Diagnosis of Rotator Cuff Tears

    Science.gov (United States)

    Lee, Ji Hyun; Jee, Sukkyung; Kwon, Jong Won; Cha, Jang Gyu; Yoo, Jae Chul

    2014-01-01

    Objective To compare the accuracy between a three-dimensional (3D) indirect isotropic T1-weighted fast spin-echo (FSE) magnetic resonance (MR) arthrography and a conventional two-dimensional (2D) T1-weighted sequences of indirect MR arthrography for diagnosing rotator cuff tears. Materials and Methods The study was approved by our Institutional Review Board. In total, 205 patients who had undergone indirect shoulder MR arthrography followed by arthroscopic surgery for 206 shoulders were included in this study. Both conventional 2D T1-weighted FSE sequences and 3D isotropic T1-weighted FSE sequence were performed in all patients. Two radiologists evaluated the images for the presence of full- or partial-thickness tears in the supraspinatus-infraspinatus (SSP-ISP) tendons and tears in the subscapularis (SSC) tendons. Using the arthroscopic findings as the reference standard, the diagnostic performances of both methods were analyzed by the area under the receiver operating characteristic curve (AUC). Results Arthroscopy confirmed 165 SSP-ISP tendon tears and 103 SSC tendon tears. For diagnosing SSP-ISP tendon tears, the AUC values were 0.964 and 0.989 for the 2D sequences and 3D T1-weighted FSE sequence, respectively, in reader I and 0.947 and 0.963, respectively, in reader II. The AUC values for diagnosing SSC tendon tears were 0.921 and 0.925, respectively, for reader I and 0.856 and 0.860, respectively, for reader II. There was no significant difference between the AUC values of the 2D and 3D sequences in either reader for either type of tear. Conclusion 3D indirect isotropic MR arthrography with FSE sequence and the conventional 2D arthrography are not significantly different in terms of accuracy for diagnosing rotator cuff tears. PMID:25469089

  7. The use of arthrography in pediatric orthopaedic surgery.

    Science.gov (United States)

    Nowicki, Philip D; Duhn, Ryan

    2014-08-01

    Surgery near pediatric joints can be challenging because it is difficult to visualize vital articular structures. Assessment of underlying pathology is also challenging because the joint structures have not yet ossified. Arthrography is a useful tool that is quick and minimally invasive and allows adequate visualization of joint anatomy during surgery, which aids intraoperative decision making. In pediatric patients, arthrography is most useful for visualization of the elbow, knee, and hip joints. This tool can help the surgeon to refine the diagnosis and management of pediatric fractures and aids in surgical assessment during joint and limb reconstruction. Arthrography adds minimal time to surgery and carries a low risk of complications; it should be part of the armamentarium of any surgeon who treats pediatric orthopaedic patients. Copyright 2014 by the American Academy of Orthopaedic Surgeons.

  8. Panoramic radiography for temporomandibular joint arthrography: a description of arthropanoramograms.

    Science.gov (United States)

    Abramovitch, K; Langlais, R P; Dolwick, M F

    1989-06-01

    TMJ arthrograms done with panoramic radiography, i.e., arthropanoramography, can demonstrate intracapsular disk displacement and perforation pathoses. These views are very practical for inferior synovial cavity arthrograms performed in the dental operatory since panoramic radiographic machines have become common in modern dental practices. Specific advantages of arthropanoramography include the decreased financial cost and decreased radiation exposure to the patient. Arthropanoramography does not replace tomography or videofluoroscopy in TMJ arthrography. It is, however, described as a simple alternative to the more conventional forms of arthrography.

  9. Epinephrine enhanced double contrast knee arthrography

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Jae Mun; Choi, Byung Ihn [Capital Armed Forces General Hospital, Seoul (Korea, Republic of)

    1981-12-15

    It is well known that double contrast knee arthrography is useful in diagnosis of meniscal lesion and other knee pathology. But intra-articular structures become less well delineated shortly after injection into the knee joint with water soluble contrast media because of rapid absorption and dilution of the injected media. This limits the time when sharply detailed arthrograms are obtained and precludes repeat delayed arthrogram without reinjection of contrast media. In order to overcome this major disadvantage, the authors used epinephrine which has vasoconstrictive effect and is expected to reduce fluid movement across the synovial membrane temporarily. The authors attempted to compare epinephrine enhanced double contrast arthrographic group, epinephrine (+) group, to the double contrast arthrographic group without epinephrine, epinephrine (-) group, by statistical evaluation. Each group consisted of 35 cases and 7 lateral films of knee joint were taken sequentially 2, 6, 10, 15, 20, 30, and 60 minutes after injection of contrast media, and were assessed by 5 certified radiologist. The results were as follows: 1. The differences of mean score of quality between epinephrine (+) group and epinephrine (-) group was statistically significant at every time interval (p value<0.01 at 2 minutes, p<0.001 at all other time interval). Epinephrine (+) group was superior to the epinephrine (-) group in quality of film. 2. Numbers of cases above score of 2 which was considered to be of diagnostic quality in evaluating meniscal lesions were larger in epinephrine (+) group than epinephrine (-) group at every time interval. And the differences between two groups was highly significant statistically (p,0.001). 3. Only 43% of cases was above score of 2 at 10 minutes in epinephrine (-) group, but 97% at 10 minutes and 80% at 20 minutes respectively in epinephrine (+) group. Therefore duration for adequate study of arthrogram is prolonged more than two times epinephrine (+) group. 4

  10. Epinephrine inhanced double contrast knee arthrography

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Jae Mun; Choi, Byung Ihn [Capital Armed Forces General Hospital, Seoul (Korea, Republic of)

    1981-09-15

    It is well known that double contrast knee arthrography is useful in diagnosis of meniscal lesions and other knee pathology. But intra-articular structures become less well delineated shortly after injection into the knee joint with water soluble contrast media because of rapid absorption and dilution of the injected media. This limits the time when sharply detailed arthrograms are obtainable and precludes repeat delayed arthrogram without reinjection of contrast media. In order to overcome this major disadvantage, the authors used epinephrine which has vasoconstrictive effect and is expected to reduce fluid movement across the synovial membrane temporarily. The authors attempted to compare epinephrine inhanced double contrast arthrographic group, epinephrine(+) group, to the double contrast arthrographic group without epinephrine, epinephrine(-) group, by statistical evaluation. Each group consisted of 35 cases and 7 lateral films of knee joint were taken sequentially 2, 6, 10, 15, 20, 30, and 60 minutes after injection of contrast media, and were assessed by 5 certified radiologists. The results were as follows: 1. The difference of mean score of quality between epinephrine(+) group and epinephrine(-) group was statistically significant at every time interval ({rho} value < 0.01 at 2 minutes, {rho} < 0.001 at all other time intervals). Epinephrine(+) group was superior to the epinephrine(-) group in quality of film. 2. Numbers of cases above score of 2 which was considered to be of diagnostic quality in evaluating meniscal lesions were larger in epinephrine(+) group than epinephrine(-) group at every time interval. And the difference between two groups was highly significant statistically ({rho} < 0.001). 3. Only 43% of cases was above score of 2 at 10 minutes in epinephrine(-) group, but 97% at 10 minutes and 80% at 20 minutes respectively in epinephrine(+) group. Therefore duration for adequate study of arthrogram is prolonged more than two times in epinephrine

  11. Ultrasonography and arthrography in rotator cuff lesions: algorithmic approach

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Eui Jong; Ryu, Kyung Nam; Lee, Sun Wha; Lim, Jae Hoon; Rhee, Yong Girl [Kyung Hee University Hospital, Seoul (Korea, Republic of); Yu, Pil Mun [Dankuk University College of Medicine, Chenona (Korea, Republic of)

    1992-11-15

    Twenty-six patients with chief complaint of shoulder pain who underwent both ultrasonographic examination and arthrography of the shoulder were analyzed. Ten out of 12 cases with clinical impression of frozen shoulder, showed normal findings on the ultrasonographic examination of the shoulder. Among these ten cases, nine cases showed adhesive capsulitis and one case showed rotator cuff tear on arthrography. Among six cases with the clinical impression of rotator cuff tear, five cases showed rotator cuff tear and one case showed combined calcific tendinitis and adhesive capsulitis on ultrasonographic examination. In arthrography, four cases of rotator cuff tear, one case of calcific tendinitis and biceps tendinitis and one case of normal finding were diagnosed. For the remaining eight cases in the ultrasonographic examination, normal finding or biceps tendinitis were found and for the remaining of the cases in arthrography adhesive capsulitis were found. With the above results, we recommend that the shoulder ultrasonography as the first line diagnostic modality for a patient with chief complaint of shoulder pain.

  12. Electric-Field-Induced Amplitude Tuning of Ferromagnetic Resonance Peak in Nano-granular Film FeCoB-SiO2/PMN-PT Composites

    Science.gov (United States)

    Luo, Mei; Zhou, Peiheng; Liu, Yunfeng; Wang, Xin; Xie, Jianliang

    2016-11-01

    One of the challenges in the design of microwave absorbers lies in tunable amplitude of dynamic permeability. In this work, we demonstrate that electric-field-induced magnetoelastic anisotropy in nano-granular film FeCoB-SiO2/PMN-PT (011) composites can be used to tune the amplitude of ferromagnetic resonance peak at room temperature. The FeCoB magnetic particles are separated from each other by SiO2 insulating matrix and present slightly different in-plane anisotropy fields. As a result, multi-resonances appear in the imaginary permeability ( μ″) curve and mixed together to form a broadband absorption peak. The amplitude of the resonance peak could be modulated by external electric field from 118 to 266.

  13. Feasibility and preliminary results of SPECT/CT arthrography of the wrist in comparison with MR arthrography in patients with suspected ulnocarpal impaction

    Energy Technology Data Exchange (ETDEWEB)

    Strobel, Klaus [Lucerne Cantonal Hospital, Department of Nuclear Medicine and Radiology, Lucerne (Switzerland); Kantonsspital Luzern, Roentgeninstitut/Nuklearmedizin, Luzern (Switzerland); Steurer-Dober, Isabelle; Huellner, Martin W.; Sol Perez Lago, Maria del; Veit-Haibach, Patrick; Tornquist, Katharina [Lucerne Cantonal Hospital, Department of Nuclear Medicine and Radiology, Lucerne (Switzerland); Silva, Angela J. da [Advanced Molecular Imaging, Philips Healthcare, San Jose, CA (United States); Bodmer, Elvira; Wartburg, Urs von; Hug, Urs [Lucerne Cantonal Hospital, Division of Hand and Plastic Surgery, Lucerne (Switzerland)

    2014-03-15

    To evaluate the feasibility and performance of SPECT/CT arthrography of the wrist in comparison with MR arthrography in patients with suspected ulnocarpal impaction. This prospective study included 28 wrists of 27 patients evaluated with SPECT/CT arthrography and MR arthrography. Iodine contrast medium and gadolinium were injected into the distal radioulnar and midcarpal joints. Late-phase SPECT/CT was performed 3.5 h after intravenous injection of approximately 650 MBq {sup 99m}Tc-DPD. MR and SPECT/CT images were separately reviewed in relation to bone marrow oedema, radionuclide uptake, and tears in the scapholunate (SL) and lunotriquetral (LT) ligaments and triangular fibrocartilage complex (TFCC), and an overall diagnosis of ulnar impaction. MR, CT and SPECT/CT imaging findings were compared with each other, with the surgical findings in 12 patients and with clinical follow-up. The quality of MR arthrography and SPECT/CT arthrography images was fully diagnostic in 23 of 28 wrists (82 %) and 25 of 28 wrists (89 %), respectively. SPECT/CT arthrography was not diagnostic for ligament lesions due to insufficient intraarticular contrast in one wrist. MR and SPECT/CT images showed concordant findings regarding TFCC lesions in 22 of 27 wrists (81 %), SL ligament in 22 of 27 wrists (81 %) and LT ligament in 23 of 27 wrists (85 %). Bone marrow oedema on MR images and scintigraphic uptake were concordant in 21 of 28 wrists (75 %). MR images showed partial TFCC defects in four patients with normal SPECT/CT images. MR images showed bone marrow oedema in 4 of 28 wrists (14 %) without scintigraphic uptake, and scintigraphic uptake was present without MR bone marrow oedema in three wrists (11 %). Regarding diagnosis of ulnar impaction the concordance rate between CT and SPECT/CT was 100 % and reached 96 % (27 of 28) between MR and SPECT/CT arthrography. The sensitivity and specificity of MR, CT and SPECT/CT arthrography were 93 %, 100 % and 100 %, and 93 %, 93 % and 93

  14. Displaceability of SLAP lesion on shoulder MR arthrography with external rotation position

    Energy Technology Data Exchange (ETDEWEB)

    Jung, Jin Young; Ha, Doo Hoe; Lee, Sang Min [CHA University, Department of Radiology, CHA Bundang Medical Center, Gyeonggi-do (Korea, Republic of); Blacksin, Marcia F. [University of Medicine and Dentistry of New Jersey, Department of Radiology, New Jersey Medical School, Newark, NJ (United States); Kim, Kyung Ah [Inje University Ilsan-Paik Hospital, Department of Radiology, Gyeonggi-do (Korea, Republic of); Kim, Jae Wha [CHA University, Department of Orthopedics, CHA Bundang Medical Center, Gyeonggi-do (Korea, Republic of)

    2011-08-15

    To investigate the usefulness of the external rotation (ER) position on magnetic resonance (MR) arthrography for the diagnosis of superior labral anterior to posterior (SLAP) lesion. Approval of institutional review board was obtained, and informed consent was waived. The MR arthrograms of 210 shoulders that were arthroscopically confirmed as SLAP lesion in 163 shoulders and intact superior labrum in 47 shoulders were retrospectively reviewed in each neutral and ER position for the diagnosis of SLAP lesion, the extent of distraction of the torn labrum, and the external rotation angle. The sensitivity, specificity, and diagnostic accuracy of MR arthrograms for determining SLAP lesion were assessed in each position. For the arthroscopically confirmed group, the diagnosis of SLAP lesion and the extent of distraction about the tear were compared between neutral and ER positions by Fisher's exact test and the paired t-test. The correlation between the external rotation angle and the diagnosis of SLAP lesion, and between the external rotation angle and the differences in the extent of distraction were evaluated in the ER position using the ANOVA test. Sensitivity and diagnostic accuracy of MR arthrography for SLAP lesion increased from 64.4% and 71.0% in the neutral position to 78.5% and 81.9% in the ER position, respectively, without change of specificity, which was 93.6% in both positions. The diagnosis of SLAP lesion was changed from negative to SLAP lesion in 16.0% of the arthroscopically confirmed group. Mean difference in the extent of distraction about the tear was 0.69 mm (range -1.40 {proportional_to} 6.67 mm), which was statistically significant. There was no relationship between the external rotation angle and the diagnosis of SLAP lesion, and between the external rotation angle and the differences in the extent of distraction. Shoulder MR arthrography with additional ER positioning helps in the diagnosis of SLAP lesion and provides information about the

  15. Immediate Reduction of a Retro-odontoid Synovial Cyst Following Lateral Atlantoaxial Joint Puncture and Arthrography: A Case Report.

    Science.gov (United States)

    Ikegami, Daisuke; Matsuoka, Takashi; Aoki, Yasuaki

    2015-05-15

    Case report. We report on a case with a retro-odontoid synovial cyst, and the immediate reduction of the cyst was confirmed after lateral atlantoaxial joint puncture and arthrography. Retro-odontoid synovial cysts are rare diseases located posteriorly to a dense axis. Because most reports have focused on surgical treatment, only a few have examined nonsurgical treatment. However, several months are required after nonsurgical treatment until cyst regression. A 52-year-old female presented with atlantoaxial instability. She complained of neck pain and numbness in her hands. Magnetic resonance imaging revealed a retro-odontoid synovial cyst. Lateral atlantoaxial joint puncture and arthrography were performed. Two days after treatment, the patient showed significant improvement in the numbness of her hands, and a follow-up magnetic resonance imaging revealed an immediate reduction in the cyst. During a 4.5-year follow-up period, no recurrence of the clinical symptoms occurred. Lateral atlantoaxial joint puncture may immediately reduce retro-odontoid synovial cysts, and the lateral atlantoaxial joint has a communication channel with the retro-odontoid synovial cyst via the atlantodental joint. Once disappearance of the cyst is confirmed, an acceptable long-term outcome can be achieved with nonsurgical treatment even in cases with atlantoaxial instability. N/A.

  16. Resonant core spectroscopies of the charge transfer interactions between C60 and the surfaces of Au(111), Ag(111), Cu(111) and Pt(111)

    Science.gov (United States)

    Gibson, Andrew J.; Temperton, Robert H.; Handrup, Karsten; O'Shea, James N.

    2017-03-01

    Charge transfer interactions between C60 and the metal surfaces of Ag(111), Cu(111), Au(111) and Pt(111) have been studied using synchrotron-based photoemission, resonant photoemission and X-ray absorption spectroscopies. By placing the X-ray absorption and valence band spectra on a common binding energy scale, the energetic overlap of the unoccupied molecular orbitals with the density of states of the underlying metal surface have been assessed in the context of possible charge transfer pathways. Resonant photoemission and resonant Auger data, measuring the valence region as a function of photon energy for C60 adsorbed on Au(111) reveals three constant high kinetic energy features associated with Auger-like core-hole decay involving an electron transferred from the surface to the LUMO of the molecule and electrons from the three highest occupied molecular orbitals, respectively and in the presence of ultra-fast charge transfer of the originally photoexcited molecule to the surface. Data for the C60/Ag(111) surface reveals an additional Auger-like feature arising from a core-hole decay process involving more than one electron transferred from the surface into the LUMO. An analysis of the relative abundance of these core-hole decay channels estimates that on average 2.4 ± 0.3 electrons are transferred from the Ag(111) surface into the LUMO. A core-hole clock analysis has also been applied to assess the charge transfer coupling in the other direction, from the molecule to the Au(111) and Ag(111) surfaces. Resonant photoemission and resonant Auger data for C60 molecules adsorbed on the Pt(111) and Cu(111) surfaces are shown to exhibit no super-Auger features, which is attributed to the strong modification of the unoccupied molecular orbitals arising from stronger chemical coupling of the molecule to the surface.

  17. Indirect MR-arthrography in osteochondral autograft and crushed bone graft with a collagen membrane-Correlation with histology

    Energy Technology Data Exchange (ETDEWEB)

    Streitparth, F. [Klinik fuer Strahlenheilkunde, Charite, Campus Virchow-Klinikum, Humboldt-University, Berlin (Germany)], E-mail: florian.streitparth@charite.de; Schoettle, P.; Schell, H. [Center for Musculoskeletal Surgery, Charite, Campus Virchow-Klinikum, Humboldt-University, Berlin (Germany); Lehmkuhl, L.; Madej, T.; Wieners, G. [Klinik fuer Strahlenheilkunde, Charite, Campus Virchow-Klinikum, Humboldt-University, Berlin (Germany); Duda, G.N. [Center for Musculoskeletal Surgery, Charite, Campus Virchow-Klinikum, Humboldt-University, Berlin (Germany); Schroeder, R.J. [Klinik fuer Strahlenheilkunde, Charite, Campus Virchow-Klinikum, Humboldt-University, Berlin (Germany)

    2009-04-15

    Objective: To analyze the spectrum of findings in indirect MR-arthrography following osteochondral autograft transfer system (OATS) and crushed bone graft using a magnetic resonance imaging (MRI) scoring and grading system in relation to histology as the standard of reference. Materials and methods: Iatrogenic lesions were set at ovine condylar facets (n = 6/group), treated with OATS or crushed bone graft. 1.5 T MRI was performed 6 months after surgery using PD-weighted (w fat saturated (fs) fast spin echo (FSE), T1-w 2D, and 3D fs gradient echo (GE) sequences 30 min. after i.v. Gd-DTPA administration and passive joint exercise. The repair tissue was evaluated by two independent radiologists. The MR findings were compared to histology. Results: In all cases, MRI and histologic grading correlated well and showed significant superior repair in OATS at 6 months (p < 0.05), reproducing the original articular contour and a good subchondral restoration. FsT1-w3DGE proved most appropriate identifying characteristic post-operative findings: the OATS group demonstrated bone marrow edema at the donor site and the graft/host interface showed significant enhancement in indirect MR-arthrography, indicating fibrocartilage. After crushed bone graft, we found an irregular structure and significant contrast uptake, consistent with remnants of bone grafts surrounded by inflammatory tissue. Conclusion: Indirect MR-arthrography is an accurate, non-invasive monitoring tool following OATS and crushed bone graft as the MRI scoring and grading system allows a reliable evaluation of normal and pathological osteochondral repair with a high histologic correlation.

  18. Rotator cuff tears: assessment with MR arthrography in 275 patients with arthroscopic correlation

    Energy Technology Data Exchange (ETDEWEB)

    Waldt, S.; Bruegel, M.; Mueller, D.; Holzapfel, K.; Rummeny, E.J.; Woertler, K. [Technische Universitaet Muenchen, Department of Radiology, Munich (Germany); Imhoff, A.B. [Technische Universitaet Muenchen, Department of Sports Orthopedics, Munich (Germany)

    2007-02-15

    We assessed the diagnostic performance of magnetic resonance (MR) arthrography in the diagnosis of articular-sided partial-thickness and full-thickness rotator cuff tears in a large symptomatic population. MR arthrograms obtained in 275 patients including a study group of 139 patients with rotator cuff tears proved by arthroscopy and a control group of 136 patients with arthroscopically intact rotator cuff tendons were reviewed in random order. MR imaging was performed on a 1.0 T system (Magnetom Expert, Siemens). MR arthrograms were analyzed by two radiologists in consensus for articular-sided partial-thickness and full-thickness tears of the supraspinatus, infraspinatus, and subscapularis tendons. At arthroscopy, 197 rotator cuff tears were diagnosed, including 105 partial-thickness (93 supraspinatus, nine infraspinatus, three subscapularis) and 92 full-thickness (43 supraspinatus, 20 infraspinatus, 29 subscapularis) tendon tears. For full-thickness tears, sensitivity, specificity, and accuracy were 96%, 99%, and 98%, respectively, and for partial tears 80%, 97%, and 95%, respectively. False negative and positive assessments in the diagnosis of articular-sided partial-thickness tears were predominantly [78% (35/45)] observed with small articular-sided (Ellman grade1) tendon tears. MR arthrography is highly accurate in the diagnosis of full-thickness rotator cuff tears and is accurate in the diagnosis of articular-sided partial-thickness tears. Limitations in the diagnosis of partial-thickness tears are mainly restricted to small articular-sided tears (Ellman grade 1) due to difficulties in differentiation between fiber tearing, tendinitis, synovitic changes, and superficial fraying at tendon margins. (orig.)

  19. Utilization of surface plasmon resonance of Au/Pt nanoparticles for highly photosensitive ZnO nanorods network based plasmon field effect transistor

    Science.gov (United States)

    Kumar, Ashish; Dixit, Tejendra; Palani, I. A.; Nakamura, D.; Higashihata, M.; Singh, Vipul

    2017-09-01

    Hydrothermally processed highly photosensitive ZnO nanorods based plasmon field effect transistors (PFETs) have been demonstrated utilizing the surface plasmon resonance coupling of Au and Pt nanoparticles at Au/Pt and ZnO interface. A significantly enhanced photocurrent was observed due to the plasmonic effect of the metal nanoparticles (NPs). The Pt coated PFETs showed Ion/Ioff ratio more than 3 × 104 under the dark condition, with field-effect mobility of 26 cm2 V-1 s-1 and threshold voltage of -2.7 V. Moreover, under the illumination of UV light (λ = 350 nm) the PFET revealed photocurrent gain of 105 under off-state (-5 V) of operation. Additionally, the electrical performance of PFETs was investigated in detail on the basis of charge transfer at metal/ZnO interface. The ZnO nanorods growth temperature was preserved at 110 °C which allowed a low temperature, economical and simple method to develop highly photosensitive ZnO nanorods network based PFETs for large scale production.

  20. Lumbar intraspinal juxtafacet cysts: MR imaging and CT-arthrography; Lumbale intraspinale Juxta-Facettenzysten: Kernspintomograpie und CT-Arthrographie

    Energy Technology Data Exchange (ETDEWEB)

    Schmid, G.; Jergas, M.; Pennekamp, W.; Bickert, U.; Koester, O. [Bochum Univ. (Germany). Klinik fuer Radiologie und Nuklearmedizin; Willburger, R. [Bochum Univ. (Germany). Klinik fuer Orthopaedie

    2002-10-01

    Purpose: To present data on the MR imaging appearance of lumbar intraspinal juxtafacet cysts (JFC) and to assess the importance of additional CT arthrography. Material and Methods: Twenty-eight patients (16 women, 12 men) with a mean age of 64 years (range: 43-82), who underwent MR imaging because of radicular pain or spinal claudication, were found to have an intraspinal cyst associated with the facet joint. In 14 patients, additional CT-arthrography was performed to determine whether a communication exists between the cyst and the facet joint and to try to rupture the cyst. Results: In T{sub 2}-weighted images, juxtafacet cysts show a typical pattern consisting of a hyperintense center and hypointense rim. The center is likely to be inhomogeneous because of recurrent hemorrhage in the cyst. In T1-weighted images, the cysts are hypo/isointense. Irregular hyperintensity may indicate subacute hemorrhage, which may aggravate the clinical symptoms. MR allows superior visualization of the cyst in all anatomical planes. It also enables assessment of typical accompanying changes, such as degenerative spondylolisthesis and facet hypertrophy. All patients, who had CT-arthrography, were found to have a direct communication between joint space and cyst. Transarticular rupture of the cyst was possible in five patients. Two of these five patients had good to excellent improvement, and the remaining three patients underwent surgery. (orig.) [German] Ziel: Darstellung der kernspintomographischen Charakteristika sowie Wertigkeit der CT-Arthrographie bei lumbalen intraspinalen Juxta-Facettenzysten (JFZ). Material und Methode: Bei 28 Patienten (16 w, 12 m) mit einem Durchschnittsalter von 64 Jahren (43-82 Jahre) wurde im Rahmen der Abklaerung einer Lumboischialgie oder einer Claudicatio spinalis eine intraspinale facettgelenksassoziierte Zyste durch CT/MR diagnostiziert. Bei 14 Patienten wurde eine CT-gesteuerte Arthrographie des betroffenen Intervertebralgelenks durchgefuehrt zum

  1. Lateral atlantoaxial joint arthrography in atlantoaxial rotatory fixation.

    Science.gov (United States)

    Hosono, Noboru; Yonenobu, Kazuo; Tada, Koichi; Yoshikawa, Hideki

    2003-04-01

    There has been much debate about the pathogenesis of atlantoaxial rotatory fixation. Intraarticular abnormality has not been well documented thus far. This is the first case of chronic atlantoaxial rotatory fixation in which atlantoaxial joints were examined by consecutive arthrography. A 7-year-old girl was diagnosed with atlantoaxial rotatory fixation on a three-dimensional CT scan. Arthrography of the lateral atlantoaxial joints indicated a rupture of the joint capsule on the dislocated side at first, followed by a successful repair after 5 weeks' immobilization with a halo apparatus. Because torticollis recurred after taking off the halo vest, we performed surgery in which severe adhesion of the cartilage surface of facet joint was noted on the undislocated side and release of the adhesion was needed to mobilize the atlas. Atlantoaxial arthrodesis by screw fixation facilitated a solid fusion of the segment.

  2. Arthrography of the TMJ. Indications, technique and interpretation

    Energy Technology Data Exchange (ETDEWEB)

    Jend, H.H.; Triebel, H.J.; Jend-Rossmann, I.

    1986-09-01

    Articular dysfunction of the TMJ with anterior displacement of the disc ('internal derangement') is an entity which has been separated from other types of the 'myofascial pain syndromes' and which can be treated conservatively or by surgery. Arthrography of the TMJ has contributed greatly to an understanding of normal and abnormal function and, in many cases, it can provide a diagnosis. On the basis of our experience with 80 investigations we discuss technical problems and the clinical indications. The indications for arthrography are in the pre-operative diagnosis, when clinical findings are uncertain, in order to demonstrate perforation, in order to confirm a suspected diagnosis and to assist in prosthetic treatment.

  3. Comparison of shoulder positions at MR arthrography: change of labroligamentous complex shape and diagnosis of labral tears

    Energy Technology Data Exchange (ETDEWEB)

    Kwak, Jin Young; Ha, Doo Hoe; Kim, Jeung Sook; Lee, Young Soo [College of Medicine, Pochon CHA Univ., Sungnam (Korea, Republic of)

    2001-11-01

    To compare the neutral, internal, and external rotation positions of the glenohumeral joint during magnetic resonance (MR) arthrography performed to assess changes in the shape of the labroligamentous complex (LLC) and in the labral tear. MR arthrography of the shoulder was retrospectively evaluated in 36 patients aged 14-66 (mean, 40) years. Fourteen cases were confirmed by arthroscopic surgery (7 SLAP lesions, 2 Bankart lesions, 1 both SLAP and Bankart lesions). Axial fat-suppressed T1-weighted spin-echo images were acquired with each shoulder in the neutral position, and with internal and external rotations. In each position, we measured the angle of rotation between the perpendicular line on the glenoid fossa and the long axis of the humeral head, analyzing the relationship between the rotational angle and changes in the shape of the LLC at each internal and external rotation, relative to the neutral position. In addition, labral tears in 14 arthroscopically confirmed joints were evaluated in each position. Mean angles of rotation relative to the neutral position were 44.1 and 45.3 degrees in internal and external rotation, respectively. Changes in the anterior LLC occurred in 25 and 24 cases of internal and external rotation, respectively. There was a significantly meaningful relationship between rotational angle and changes in the shape of the anterior LLC during external rotation, and when this changes was noticed, the rotational angle was wider (p<0.05). The posterior LLC changed in shape in 13 and 16 cases of internal and external rotation, respectively, but changes according to the angle of rotation were not statistically significant. In arthroscopically confirmed joints, diagnosis of the eight SLAP lesions at external rotation tended to become more accurate, but no statistically significant differences were noted (p=0.07). Two Bankart lesions were interpreted as a tear in all three positions, and one other such lesion was interpreted as a tear in the

  4. Inadvertent intraosseous gadolinium injection during pediatric shoulder MR arthrography

    Energy Technology Data Exchange (ETDEWEB)

    Pack, Jason R.; Jordanov, Martin I.; Block, John J. [Vanderbilt University Medical Center, Department of Radiology and Radiological Sciences, Nashville, TN (United States)

    2008-07-15

    A variety of problems can arise while performing MR arthrography of the shoulder. These have been well documented in the literature and range from improper patient selection to errors in technique or in the choice of imaging sequences. We present a rare case of inadvertent, painless intraosseous injection of dilute gadolinium into the proximal humeral epiphysis of a 13-year-old male athlete. The clinical relevance is discussed and technical recommendations are offered. (orig.)

  5. Investigation of the commensurate magnetic structure in the heavy-fermion compound CePt2In7 using magnetic resonant x-ray diffraction

    Science.gov (United States)

    Gauthier, Nicolas; Wermeille, Didier; Casati, Nicola; Sakai, Hironori; Baumbach, Ryan E.; Bauer, Eric D.; White, Jonathan S.

    2017-08-01

    We investigated the magnetic structure of the heavy-fermion compound CePt2In7 below TN=5.34 (2 ) K using magnetic resonant x-ray diffraction at ambient pressure. The magnetic order is characterized by a commensurate propagation vector k1 /2=(1/2 ,1/2 ,1/2 ) with spins lying in the basal plane. Our measurements did not reveal the presence of an incommensurate order propagating along the high-symmetry directions in reciprocal space but cannot exclude other incommensurate modulations or weak scattering intensities. The observed commensurate order can be described equivalently by either a single-k structure or by a multi-k structure. Furthermore we explain how a commensurate-only ordering may explain the broad distribution of internal fields observed in nuclear quadrupolar resonance experiments [Sakai et al., Phys. Rev. B 83, 140408 (2011), 10.1103/PhysRevB.83.140408] that was previously attributed to an incommensurate order. We also report powder x-ray diffraction showing that the crystallographic structure of CePt2In7 changes monotonically with pressure up to P =7.3 GPa at room temperature. The determined bulk modulus B0=81.1 (3 ) GPa is similar to those of the Ce-115 family. Broad diffraction peaks confirm the presence of pronounced strain in polycrystalline samples of CePt2In7 . We discuss how strain effects can lead to different electronic and magnetic properties between polycrystalline and single crystal samples.

  6. Augmented Reality Visualization with Use of Image Overlay Technology for MR Imaging–guided Interventions: Assessment of Performance in Cadaveric Shoulder and Hip Arthrography at 1.5 T

    Science.gov (United States)

    Fritz, Jan; U-Thainual, Paweena; Ungi, Tamas; Flammang, Aaron J.; Fichtinger, Gabor; Iordachita, Iulian I.

    2012-01-01

    Purpose: To prospectively assess overlay technology in providing accurate and efficient targeting for magnetic resonance (MR) imaging–guided shoulder and hip joint arthrography. Materials and Methods: A prototype augmented reality image overlay system was used in conjunction with a clinical 1.5-T MR imager. A total of 24 shoulder joint and 24 hip joint injections were planned in 12 human cadavers. Two operators (A and B) participated, each performing procedures on different cadavers using image overlay guidance. MR imaging was used to confirm needle positions, monitor injections, and perform MR arthrography. Accuracy was assessed according to the rate of needle adjustment, target error, and whether the injection was intraarticular. Efficiency was assessed according to arthrography procedural time. Operator differences were assessed with comparison of accuracy and procedure times between the operators. Mann-Whitney U test and Fisher exact test were used to assess group differences. Results: Forty-five arthrography procedures (23 shoulders, 22 hips) were performed. Three joints had prostheses and were excluded. Operator A performed 12 shoulder and 12 hip injections. Operator B performed 11 shoulder and 10 hip injections. Needle adjustment rate was 13% (six of 45; one for operator A and five for operator B). Target error was 3.1 mm ± 1.2 (standard deviation) (operator A, 2.9 mm ± 1.4; operator B, 3.5 mm ± 0.9). Intraarticular injection rate was 100% (45 of 45). The average arthrography time was 14 minutes (range, 6–27 minutes; 12 minutes [range, 6–25 minutes] for operator A and 16 minutes [range, 6–27 min] for operator B). Operator differences were not significant with regard to needle adjustment rate (P = .08), target error (P = .07), intraarticular injection rate (P > .99), and arthrography time (P = .22). Conclusion: Image overlay technology provides accurate and efficient MR guidance for successful shoulder and hip arthrography in human cadavers.

  7. Irreversible magnetic-field dependence of ferromagnetic resonance and inverse spin Hall effect voltage in CoFeB/Pt bilayer

    Science.gov (United States)

    Kim, Sang-Il; Seo, Min-Su; Choi, Yeon Suk; Park, Seung-Young

    2017-01-01

    Magnetic field (H) sweeping direction dependences of the mixed voltage Vmix induced by the inverse-spin Hall effect(ISHE) and spin-rectified effect (SRE) in a CoFeB (5 nm)/Pt (10 nm) bilayer structure are investigated using the ferromagnetic resonance in the TE mode cavities and coplanar waveguide methods. Conventionally, the magnitude of ISHE voltage VISH (symmetric) excluding the SRE (antisymmetric component) was unavoidably separated from the fitting curve of Vmix (a sum of a symmetric and an antisymmetric part) for one direction of H-source. By studying the ratio of the two voltage parts with the bi-directional H sweeping, the optimized VISH (no SRE condition) value which also include a well-defined spin Hall angle can be obtained via the linear response relation of ISHE and SRE components.

  8. Arthrography, talar tilt and surgical findings after inversion trauma of the ankle

    Energy Technology Data Exchange (ETDEWEB)

    van Moppes, F.I.; van den Hoogenband, C.R.; van Engelshoven, J.M.; Betts-Brown, A.

    1981-04-01

    Both inversion stress examination under general anesthesia and arthrography are sensitive indicators of lateral ankle ligament pathology (91%, 96% resp.). Arthrography is significantly superior to inversion stress examination done under local anesthesia (96%, 70% resp.). Peroneus tendon sheath filling is always pathological, but although this does not always indicate calcaneo-fibular ligament rupture, such rupture cannot be excluded in its absence. Talar tilt difference cannot be correlated with the extent of ligamentous rupture and therefore inversion stress examination, while providing valuable additional information, must be regarded as a secondary technique to ankle arthrography.

  9. Giant Electric Field Control of Magnetism and Narrow Ferromagnetic Resonance Linewidth in FeCoSiB/Si/SiO2/PMN PT Multiferroic Heterostructures (Open Access Author’s Manuscript)

    Science.gov (United States)

    2016-06-06

    1 Giant electric field control of magnetism and narrow ferromagnetic resonance linewidth in FeCoSiB/Si/SiO2/PMN-PT multiferroic heterostructures...coupling and narrow ferromagnetic resonance (FMR) linewidth in multiferroic heterostructures. Electric field induced large effective field of 175Oe...in which the electric field applied to the piezoelectric layer produces a mechanical deformation that couples to the magnetic film, and hence induces

  10. Utility of MR arthrography in the diagnosis of adhesive capsulitis

    Energy Technology Data Exchange (ETDEWEB)

    Manton, G.L.; Schweitzer, M.E.; Weishaupt, D.; Karasick, D. [Dept. of Radiology, Thomas Jefferson Univ. Hospital, Philadelphia, PA (United States)

    2001-06-01

    Objective. Arthrographically, adhesive capsulitis is characterized by decreased joint volume; histologically, the capsule and synovium are thickened. We therefore compared using MR arthrography the joint volumes and capsule/synovial thickness of patients with and without adhesive capsulitis in order to assess the utility of MR arthrography in diagnosing adhesive capsulitis.Design and patients. The 1.5 T MR arthrography images of 28 subjects with (n=9) and without (n=19) adhesive capsulitis were compared. Adhe- sive capsulitis was diagnosed when there was an injected glenohumeral joint volume of less than 10 ml. Two masked observers working in consensus assessed the images for the relative amount of fluid in the biceps tendon sheath and axillary recess, corrugation at the margin of the capsule, capsule/synovial thickness, abnormalities of the rotator interval capsule, and for the presence of a cuff tear.Results. There was a trend towards differences in capsular and synovial thickness (P>0.07) between the subjects with and without adhesive capsulitis; however, the controls had thicker synovium/capsules. Surprisingly, the amount of fluid in the axillary recess and biceps tendon sheath was not significantly different between the groups (P>0.25). There were more tears of the rotator cuff in controls than in patients with adhesive capsulitis (6, 3 vs 1, 1: complete, partial). Also, both corrugation (7 vs 0) and interval abnormalities (7 vs 0) were more common in the controls.Conclusion. There appear to be no useful MR arthrographic signs of adhesive capsulitis. Capsular/synovial thickness, static fluid volume, and the presence of corrugation are inconclusive as MR arthrographic signs for distinguishing shoulders with adhesive capsulitis from those without. (orig.)

  11. Feasibility of ultrasonography and MR arthrography during evaluation of rotator cuff injury

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    Hu, Jin Guang [Yanji Hospital, Jilin (China); Lee, Jong Min; Ryeom, Hun Kyu [School of Medicine Kyungpook National University, Daegu (Korea, Republic of)

    2005-10-15

    To evaluate the feasibility of MR arthrography and ultrasonography in evaluating shoulder pain. The subject group consisted of all patients who visited our institute complaining of shoulder pain or instability form June 2002 to December 2004. There were a total of 92 patients with an mean age of 48. On the basis of arthroscopic results, the sensitivity, specificity, and accuracy of ultrasonography and MR arthrography were evaluated by comparing them with each other. In the diagnosis of separateness tendon tears, ultrasonography had sensitivity and specificity of 100% and 64%, respectively, whereas MR arthrography had sensitivity and specificity of 80% and 94%, respectively. Ultrasonography also had high sensitivity and specificity in the diagnosis of subscapularis tendon tears (100% and 90%). MR arthrography was appropriate for identifying glenoid labral abnormalities (sensitivity, 95% and specificity, 61%). Similar results from ultrasonography and MR arthrography were obtained in the diagnosis of subscapular tendon tears or full-thickness tears of the rotator cuff tendons (kappa value, 0.644 and 0.911). While evaluating rotator cuff abnormalities, ultrasonography was appropriate for screening, whereas MR arthrography was useful to confirm the results of the ultrasonography.

  12. Efficacy of ultrasonography-guided shoulder MR arthrography using a posterior approach

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    Gokalp, Gokhan; Dusak, Abdurrahim; Yazici, Zeynep [Uludag University Medical Faculty, Goeruekle Kampusu, Department of Radiology, Bursa (Turkey)

    2010-06-15

    Shoulder MR arthrography has an important role in the assessment of rotator cuff lesions, labral tears, glenohumeral ligaments, rotator interval lesions, and postoperative shoulder status. Injection in direct MR arthrography can be performed with palpation, fluoroscopy, ultrasonography (US), or MRI. Recently, the posterior approach is the preferred method due to the presence of fewer stabilizers, absence of important articular structures and less extravasation, has been advocated. Our aim was to assess the efficacy of US-guided MR arthrography via a posterior approach on the glenohumeral joint. Thirty MR arthrographies were performed on 29 patients. Ultrasonography (Xario, Toshiba) examinations were conducted by a wide-band 5-12 Mhz linear array transducer set to muscle-skeleton. Diluted contrast medium (1 ml gadolinium chelate and 100 ml saline, approximately 15 ml) was delivered into the glenohumeral joint space from between the humeral head and posterior labrum with a 20-gauge spinal needle. MRI examination was conducted by a 1.5 T scanner. Fat-saturated T1-weighted spin echo was applied on coronal, axial, and sagittal planes within the first 30 min after contrast material injection. One (3.3%) arthrography was not successful due to technical reasons associated with obesity. Contrast extravasation around the infraspinatus and teres minoer muscles was depicted in twelve examinations. One (3.3%) patient developed vasovagal collapse. Ultrasonography-guided posterior approach is an easy, reliable, fast, and comfortable method in experienced hands. It may be an alternative for fluoroscopy-guided shoulder MR arthrography. (orig.)

  13. Multidetector Computed Tomography Arthrography of the Shoulder: Diagnostic Accuracy and Indications

    Energy Technology Data Exchange (ETDEWEB)

    De Filippo, M.; Bertellini, A.; Sverzellati, N.; Pogliacomi, F.; Costantino, C.; Vitale, M.; Zappia, M.; Corradi, D.; Garlaschi, G.; Zompatori, M. (Dept. of Clinical Sciences, Section of Radiological Sciences, Univ. of Parma, Parma Hospital, Parma (Italy))

    2008-06-15

    Background: The presence of subcutaneous implants, such as permanent defibrillators, is an absolute contraindication to the use of magnetic resonance imaging (MRI). Moreover, MRI is unadvisable in subjects with metallic hardware near the area of study, as artifacts generated by such materials distort image quality. Purpose: To evaluate the diagnostic accuracy and indications of arthrography with multidetector computed tomography arthrography (arthro-MDCT) of the shoulder in patients with absolute or relative contraindications to MRI and in patients with periarticular metal implants using diagnostic arthroscopy as the gold standard. Material and Methods: After intraarticular injection of iodixanol and volumetric acquisition, 70 shoulders in 70 patients (30 females, 40 males, age range 32-60 years) were examined with a 16-detector-row CT scanner. The patients had arthralgia but no radiologically detected fractures. They could not be studied by MRI because of absolute contraindications (subcutaneous electronic implants), surgical metal implants, or claustrophobia. In 28 of the 70 patients who had had previous shoulder surgery, the arthro-CT examination was preceded by an MRI on the same day. All examinations were interpreted by two experienced musculoskeletal radiologists. The findings were compared with arthroscopic findings carried out within 28 days of the CT study. Results: In the 42 non-operated patients, the comparison between arthro-MDCT and arthroscopy showed sensitivity and specificity ranging between 87% and 100%. In the 28 operated shoulders, arthro-MDCT had an accuracy of 94% compared with 25% with MRI. Interobserver agreement was almost perfect (kappa=0.95) in the evaluation of all types of lesions, both on MDCT and MRI. When arthro-MDCT was compared with MRI in the postoperative patients by a McNemar test, a significant difference (P<0.05) was found between these two techniques. Conclusion: Arthro-MDCT of the shoulder is a safe technique that provides

  14. Diagnostic Value of CT Arthrography for Evaluation of Osteochondral Lesions at the Ankle

    Directory of Open Access Journals (Sweden)

    Jan S. Kirschke

    2016-01-01

    Full Text Available Background. To retrospectively determine the diagnostic value of computed tomography arthrography (CTA of the ankle in the evaluation of (osteochondral lesions in comparison to conventional magnetic resonance imaging (MRI and intraoperative findings. Methods. A total of N=79 patients had CTAs and MRI of the ankle; in 17/79 cases surgical reports with statements on cartilage integrity were available. Cartilage lesions and bony defects at talus and tibia were scored according to defect depth and size by two radiologists. Statistical analysis included sensitivity analyses and Cohen’s kappa calculations. Results. On CTA, 41/79 and 31/79 patients had full thickness cartilage defects at the talus and at the tibia, respectively. MRI was able to detect 54% of these defects. For the detection of full thickness cartilage lesions, interobserver agreement was substantial (0.72 ± 0.05 for CTA and moderate (0.55 ± 0.07 for MRI. In surgical reports, 88–92% and 46–62% of full thickness defects detected by CTA and MRI were described. CTA findings changed the further clinical management in 15.4% of cases. Conclusions. As compared to conventional MRI, CTA improves detection and visualization of cartilage defects at the ankle and is a relevant tool for treatment decisions in unclear cases.

  15. Magnetic resonance imaging and magnetic resonance arthography of the acetabular labrum: Comparison with surgical findings; Magnetresonanztomographie und Magnetresonanzarthrographie des Labrum acetabulare: Vergleich mit operativen Ergebnissen

    Energy Technology Data Exchange (ETDEWEB)

    Czerny, C. [Universitaetsklinik fuer Radiodiagnostik, Vienna (Austria). Abt. fuer Osteologie; Kramer, J. [Universitaetsklinik fuer Radiodiagnostik, Vienna (Austria). Abt. fuer Osteologie; Institut fuer bildgebende Diagnostik am Schillerpark, Linz (Austria); Neuhold, A. [Krankenhaus Rudolfinerhaus, Vienna (Austria). Inst. fuer bildgebende Diagnostik; Urban, M. [Krankenhaus Sozialmedizinisches Zentrum Ost, Vienna (Austria). Abt. fuer Radiodiagnostik; Tschauner, C. [Orthopaedisches Landeskrankenhaus Stolzalpe (Austria); Hofmann, S. [Krankenhaus Sozialmedizinisches Zentrum Ost, Vienna (Austria). Abt. fuer Radiodiagnostik; Orthopaedisches Landeskrankenhaus Stolzalpe (Austria)

    2001-08-01

    Aim of the study: To evaluate the accuracy of magnetic resonance imaging (MRI) and magnetic resonance (MR) arthrography in detecting acetabular labral lesions in correlation to surgical findings. Patients and methods: Forty patients (40 hips) with chronic hip pain and a strong clinical suspicion of labral lesions were examined with MRI in the coronal and axial plane by obtaining T{sub 1} weighted and proton density-weighted spin echo sequences. Additionally, MR arthrography of the high joint in the coronal oblique and sagittal oblique plane was performed by obtaining T{sub 1}-weighted three-dimensional gradient echo sequences after the intraarticular injection of gadopentate dimeglumine. The labra were prospectively evaluated on the basis of morphology, signal intensity, the presence or absence of a tear, and their attachment to the acetabulum. All patients underwent surgery, and the MRI findings and MR arthrography findings were compared with the surgical results. Results: Surgically, 34 labral lesions, and 6 normal labra were detected. MRI correctly depicted labral lesions in 24 patients and two normal labra, and MR arthrography correctly depicted labral lesions in 30 patients and 5 normal labra compared with the surgical results. The sensitivity of MRI was 80%, the accuracy of MRI was 65%, the sensitivity of MR arthrography was 95%, and the accuracy of MR arthgrography was 88%. Conclusions: MR arthrography enables considerably more accurate detection of acetabular labral lesions than MRI. MR arthrography should be the method of choice for the diagnosis of the presence or absence of acetabular labral lesions in patients with chronic hip pain and a strong clinical suspicion of labral lesions. (orig.) [German] Ziel: Die Bestimmung der Wertigkeit der konventionellen Magnetresonanztomographie (MRT) und der Magnetresonanzarthrographie (MR-Arthrographie) in der Abklaerung von Laesionen des Labrum acetabulare im Vergleich mit Operationsbefunden (Goldstandard). Methode

  16. SLAP tears: diagnosis using 3-T shoulder MR arthrography with the 3D isotropic turbo spin-echo space sequence versus conventional 2D sequences

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    Jung, Joon-Yong; Jee, Won-Hee; Park, Michael Yong [The Catholic University of Korea, Department of Radiology, Seoul St. Mary' s Hospital, College of Medicine, Seoul (Korea, Republic of); Lee, So-Yeon [Sungkyunkwan University School of Medicine, Department of Radiology, Kangbuk Samsung Hospital, Seoul (Korea, Republic of); Kim, Yang-Soo [The Catholic University of Korea, Department of Orthopaedic Surgery, Seoul St. Mary' s Hospital, College of Medicine, Seoul (Korea, Republic of)

    2013-02-15

    The aim of this study was to determine the accuracy and reliability of shoulder magnetic resonance (MR) arthrography with three-dimensional (3D) isotropic intermediate-weighted turbo spin-echo (TSE) sampling perfection with application-optimised contrasts using different flip angle evolution (SPACE) in the diagnosis of superior labrum anterior-to-posterior (SLAP) lesions compared with two-dimensional (2D) TSE at 3.0 T. MR arthrograms, including 2D TSE and 3D TSE-SPACE, in 87 patients who underwent arthroscopy were retrospectively analysed by two reviewers for the presence and type of SLAP lesions. Sensitivity and specificity were compared using McNemar's test, and inter-observer agreement was calculated using Cohen's kappa. Receiver operating characteristic (ROC) curve analyses were performed. The mean sensitivity, specificity and accuracy were 90%, 85% and 86% for 2D TSE, and 81%, 86% and 85% for 3D TSE-SPACE respectively, with no statistically significant differences. Inter-observer agreements were substantial in 2D TSE ({kappa} = 0.76) and 3D TSE-SPACE ({kappa} = 0.68). The areas under the ROC curves were 0.92 for 2D TSE and 0.90 for 3D TSE-SPACE, which were not significantly different. MR arthrography with 3D TSE-SPACE showed comparable accuracy and substantial inter-observer agreement for the diagnosis of SLAP lesions circle MR arthrography is regarded as the definitive method of shoulder imaging circle Different MR sequences are evolving for SLAP lesions circle 3D TSE-SPACE demonstrated comparable overall accuracy to 2D TSE for SLAP lesions. (orig.)

  17. Femoro-acetabular impingement: can indirect MR arthrography be considered a valid method to detect endoarticular damage? A preliminary study.

    Science.gov (United States)

    Pozzi, Grazia; Stradiotti, Paola; Parra, Cleber Garcia; Zagra, Luigi; Sironi, Sandro; Zerbi, Alberto

    2009-01-01

    To assess the effectiveness of indirect Magnetic Resonance arthrography (i-MRa) in the detection of chondral and labral lesions related to femoro-acetabular impingement (FAI) a series of 21 hip joints in 17 patients with a clinical diagnosis of FAI were examined either with standard MR imaging, i-MRa and direct-MR arthrography (d-MRa). Sensitivity and accuracy of i-MRa in detecting chondral, labral and tardive lesions were calculated and compared with standard MR. The agreement in detecting endoarticular damage between i-MRa and d-MRa and the interobserver agreement was assessed by K statistic (p<0.05). Finally the presence of trocanteric bursitis was evaluated. I-MRa showed higher values of both sensivity and accuracy than standard MR in detecting chondral damage, with an increase to 92% for the first item and 95% for the second. The same was noticed in labrum evaluation with an increase to 88% and 90% respectively. The level of agreement between i-MRa and d-MRa in detection of chondral lesions was excellent, substantial for the labral damage and absolute for early osteoarthritic changes. An excellent interobserver agreement resulted in detection of both chondral and labral damages with i-MRa. In 6 hips (28,5%) we also found the presence of peri-trochanteric soft tissue inflammation that indicated the possibility of extrarticular involvement in FAI. Indirect-MRa can be considered a valid method of assessing endoarticular damage related to FAI, in comparison to d-MRa. It should be performed instead of standard MR if d-MRa is not available.

  18. Supraspinatus tendon tears: comparison of 3D US and MR arthrography with surgical correlation

    Energy Technology Data Exchange (ETDEWEB)

    Kang, Chang Ho [Kangwon National University Hospital, Department of Radiology, Kangwon-do (Korea); Korea University Anam Hospital, Korea University College of Medicine, Department of Radiology, Seoul (Korea); Kim, Sam Soo [Kangwon National University Hospital, Department of Radiology, Kangwon-do (Korea); Kim, Jung Hyuk; Chung, Kyoo Byung; Kim, Yun Hwan; Oh, Yu-Whan [Korea University Anam Hospital, Korea University College of Medicine, Department of Radiology, Seoul (Korea); Jeong, Woong-Kyo [Korea University Anam Hospital, Korea University College of Medicine, Orthopaedic Surgery, Seoul (Korea); Kim, Baek Hyun [Korea University Ansan Hospital, Korea University College of Medicine, Department of Radiology, Ansan City (Korea)

    2009-11-15

    The objective of the study was to compare the diagnostic reliability of 3D US with MR arthrography in diagnosing supraspinatus tendon tears, with arthroscopic findings used as the standard. In a prospective study 50 patients who later underwent arthroscopic surgery of the rotator cuff were examined pre-operatively by 3D US with MR arthrography. The presence or absence of a full- or partial-thickness supraspinatus tendon tear and the tear size as demonstrated by each imaging and arthroscopy was recorded. The tear size was divided into three grades: small (<1 cm), medium (1-3 cm), and large (>3 cm). The arthroscopic diagnosis was a full-thickness tear in 40 patients, partial-thickness tears in 5, and intact supraspinatus tendon in 5. 3D US correctly diagnosed 35 out of 40 full-thickness tears and MR arthrography 39 out of 40 full-thickness tears. Regarding partial-thickness tears, 3D US underestimated 2 cases as no tear and overestimated 1 case as a full-thickness tear. MR arthrography underestimated 1 case as a partial-thickness tear and overestimated 2 cases as full-thickness and partial-thickness tears respectively. 3D US and MR arthrography yield a sensitivity for full-thickness tears of 87.5% and 97.5% with specificity of 90.0% and 90.0%. Based on the grading system, 3D US measurements correctly predicted the tear size of 23 (65.7%) of the 35 full-thickness tears and MR arthrography 30 (75.0%) of the 39 full-thickness tears. Three-dimensional ultrasound seems to be a promising imaging modality comparable to MR arthrography for the assessment of the supraspinatus tendon tears. (orig.)

  19. Paralabral cysts in the hip joint: findings at MR arthrography

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    Magerkurth, Olaf [University of Michigan, Department of Radiology, Ann Arbor, MI (United States); University Children' s Hospital, Department of Radiology, Basel (Switzerland); Jacobson, Jon A.; Girish, Gandikota; Kalume Brigido, Monica; Fessell, David [University of Michigan, Department of Radiology, Ann Arbor, MI (United States); Bedi, Asheesh [University of Michigan, Department of Orthopedic Surgery, Ann Arbor, MI (United States)

    2012-10-15

    The purpose of this research was to retrospectively characterize paralabral cysts of the hip as seen at MR arthrography. After Institutional Review Board approval, 704 patients who had MR arthrography were identified over a 3-year period and 40 patients were identified as having a cyst or fluid collection at the hip by MR report. MR images from these 40 patients were retrospectively reviewed by three radiologists where 18 were found to have a paralabral cyst, which were characterized as follows: location, configuration, contrast filling, size of the cyst, extent, direction, and whether associated osseous changes were present. In addition, the acetabular labrum was assessed for tears and, if present, the location and pattern were characterized. Paralabral cysts were located anterosuperiorly in 56%, anteriorly in 22%, posterosuperiorly in 17%, and anteroinferiorly in 6% of cases. The vast majority (94%) were multilocular and filled with intra-articular contrast medium. The average dimensions were 8 x 7 x 11 mm. The paralabral cyst demonstrated extracapsular extension in 72% of cases, with 39% located between the ilium and gluteus minimus, and 22% between the ilium and iliopsoas. Remodeling of the ilium adjacent to the cyst was observed in 50% of these cases. A labral tear was at the base of the labrum adjacent to the cyst in 78% of cases, while the tear was isolated to the body of the labrum in 22%. Tears were most commonly anterosuperior (55%) or anterior (28%) in location. Our results show that paralabral cysts of the hip are most commonly located anterosuperiorly, are multilocular, fill with intra-articular contrast medium, have average dimensions up to 11 mm, and often extend extracapsularly between muscle and bone where they may remodel the adjacent ilium. (orig.)

  20. Cone-beam computed tomography arthrography: an innovative modality for the evaluation of wrist ligament and cartilage injuries

    Energy Technology Data Exchange (ETDEWEB)

    Ramdhian-Wihlm, Reeta [University Hospital of Strasbourg, Department of Orthopedic Surgery, Strasbourg (France); Le Minor, Jean-Marie [University of Strasbourg, Institute of Anatomy, Strasbourg (France); University of Strasbourg, Faculty of Dentistry, Strasbourg (France); Schmittbuhl, Matthieu [University of Strasbourg, Faculty of Dentistry, Strasbourg (France); Jeantroux, Jeremy; Veillon, Francis; Dosch, Jean-Claude; Dietemann, Jean-Louis; Bierry, Guillaume [University Hospital of Strasbourg, Department of Radiology, Strasbourg (France); Mahon, Peter Mac [Massachusetts General Hospital, Department of Musculoskeletal Radiology, Boston, MA (United States)

    2012-08-15

    Cone-beam computed tomography (CBCT) has become an important modality in dento-facial imaging but remains poorly used in the exploration of the musculoskeletal system. The purpose of this study was to prospectively evaluate the performance and radiation exposure of CBCT arthrography in the evaluation of ligament and cartilage injuries in cadaveric wrists, with gross pathology findings as the standard of reference. Conventional arthrography was performed under fluoroscopic guidance on 10 cadaveric wrists, followed by MDCT acquisition and CBCT acquisition. CBCT arthrography and MDCT arthrography images were independently analyzed by two musculoskeletal radiologists working independently and then in consensus. The following items were observed: scapholunate and lunotriquetral ligaments, triangular fibrocartilage complex (TFCC) (tear, integrity), and proximal carpal row cartilage (chondral tears). Wrists were dissected and served as the standard of reference for comparisons. Interobserver agreement, sensitivity, specificity, and accuracy were determined. Radiation dose (CTDI) of both modalities was recorded. CBCT arthrography provides equivalent results to MDCT arthrography in the evaluation of ligaments and cartilage with sensitivity and specificity between 82 and 100%, and interobserver agreement between 0.83 and 0.97. However, radiation dose was significantly lower (p < 0.05) for CBCT arthrography than for MDCT arthrography with a mean CTDI of 2.1 mGy (range 1.7-2.2) versus a mean of 15.1 mGy (range 14.7-16.1). CBCT arthrography appears to be an innovative alternative to MDCT arthrography of the wrist as it allows an accurate and low radiation dose evaluation of ligaments and cartilage. (orig.)

  1. MR arthrography of elbow: evaluation of the ulnar collateral ligament of elbow

    Energy Technology Data Exchange (ETDEWEB)

    Nakanishi, Katsunuki [Department of Radiology, Osaka University Medical School, 2-2 Yamadaoka, Suita-city, Osaka 565 (Japan); Masatomi, Takashi [Department of Orthopedic Surgery, Osaka University Medical School, Osaka (Japan); Ochi, Takahiro [Department of Orthopedic Surgery, Osaka University Medical School, Osaka (Japan); Ishida, Takeshi [Department of Radiology, Osaka University Medical School, 2-2 Yamadaoka, Suita-city, Osaka 565 (Japan); Hori, Shinichi [Department of Radiology, Izumisano Municipal Hospital, Osaka (Japan); Ikezoe, Junpei [Department of Radiology, Osaka University Medical School, 2-2 Yamadaoka, Suita-city, Osaka 565 (Japan); Nakamura, Hironobu [Department of Radiology, Osaka University Medical School, 2-2 Yamadaoka, Suita-city, Osaka 565 (Japan)

    1996-10-01

    Objective. The purpose of this study was to evaluate ulnar collateral ligament (UCL) injury of the elbow in throwing athletes by MRI and MR arthrography. Design. Ten elbows of throwing athletes were examined on both plain MRI and MR saline arthrography and the injuries subsequently surgically proven. Spin-echo (SE) T1-weighted and fast SE T2-weighted coronal images were obtained. Results. The UCL was unclear in all ten cases on T1-weighted MRI. In five cases an avulsion fracture was also found on T1-weighted MRI. On T2-weighted MRI, abnormal high-intensity areas were identified in or around the UCL. On T2-weighted MR arthrography images, extracapsular high-intensity areas, which represent extracapsular leakage, were found in four of five cases with avulsion fracture. At surgery, all these four cases showed avulsion fractures with instability; the other case had a fracture but it was stable and adherent to the humerus. On T2-weighted MR arthrography images, an extracapsular high-intensity area was found in one of the five cases without avulsion fracture. At surgery this patient had a complete tear of the UCL itself. Conclusion. MR arthrography provided additional information for evaluating the degree of UCL injury. (orig.). With 5 figs., 1 tab.

  2. Low-field MR arthrography of the shoulder joint: technique, indications, and clinical results

    Energy Technology Data Exchange (ETDEWEB)

    Kreitner, K.-F.; Thelen, M. [Department of Radiology, Johannes Gutenberg University, Langenbeckstrasse 1, 55131 Mainz (Germany); Loew, R. [Department of Radiology, Johannes Gutenberg University, Langenbeckstrasse 1, 55131 Mainz (Germany); Department of Radiology, University Hospital, 1201 Basel (Switzerland); Runkel, M. [Department of Traumatology, Johannes Gutenberg University, Langenbeckstrasse 1, 55131 Mainz (Germany); Department of Traumatology and Hand Surgery, Klinikum Konstanz, Konstanz (Germany); Zoellner, J. [Department of Orthopedic Surgery, Johannes Gutenberg University, Langenbeckstrasse 1, 55131 Mainz (Germany)

    2003-02-01

    In the age of cost containment and urgent reductions in health care expenditures, new options have to be explored to satisfy both diagnostic requirements and economic limitations. The introduction of low-field MR systems for assessment of joint disorders seemed to be an option for lower costs. The purpose of this article is to summarize available experiences with low-field MR arthrography of the glenohumeral joint with respect to image quality and diagnostic accuracy in detecting labral and rotator cuff lesions. Up to now, there has been only a limited number of studies available dealing with low-field MR arthrography of the glenohumeral joint. They reveal that, despite a minor image quality in comparison with high-field imaging, low-field MR arthrography of the shoulder allows for sufficient evaluation of intra- and extra-articular structures in the detection of major abnormalities such as glenohumeral instability or rotator cuff disease. Furthermore, open-configured MR scanners enable kinematic studies: Besides the analysis of normal motion, pathological findings in patients with instabilities and impingement syndrome can be delineated. They further offer the possibility for performing MR imaging-guided arthrography of the shoulder. This was first described using an open C-arm scanner with a vertically oriented magnetic field so that MR arthrography may be performed in one setting. (orig.)

  3. Indirect MR arthrography in the evaluation of tears of the glenoid labrum; Indirekte MR-Arthrographie in der Diagnostik von Laesionen des Labrum glenoidale

    Energy Technology Data Exchange (ETDEWEB)

    Sommer, T.; Vahlensieck, M.; Lutterbey, G.; Pauleit, D.; Kreft, B.; Keller, E.; Schild, H. [Radiologische Universitaetsklinik Bonn (Germany); Wallny, T. [Orthopaedische Universitaetsklinik Bonn (Germany); Steuer, K.; Golombek, V. [Klinik fuer Unfallchirurgie, Univ. Bonn (Germany)

    1997-07-01

    Purpose: It has been shown that intravenous administration of contrast media produces an MR arthrographic effect without the need for intraarticular injection. This is the first study evaluating this new technique of indirect MR arthrography in the diagnosis of glenoid labrum tears. Methods: 28 patients with clinically suspected labral injuries were prospectively investigated (1.5 Tesla, flexible surface coil). A plain MR examination of the shoulder (transverse and oblique-coronal orientation, T{sub 1}-weighted spin- [T{sub E}/T{sub R} 15/675], proton density- and T{sub 2}*-weighted gradient echo [T{sub E}/T{sub R}/Flip 14,32/600/30 ] sequences) and indirect MR arthrography (transverse and oblique-coronal orientation, fat-suppressed T{sub 1}-weighted spin-echo sequences [T{sub E}/T{sub R} 15/675], intravenous injection of gadopentetate dimeglumine [0.1 mmol/kg], followed by 10-15 min of joint movement) were performed. Results were confirmed by arthroscopy and/or open surgery. Results: Indirect MR arthrography significantly improved delineation of the glenoid labrum and hyaline cartilage (p<0.05). Sensitivity and specificity of indirect MR arthrography in the diagnosis of labral injuries were 90% and 89%, compared to 79% and 67% of the native MR examination. Conclusion: Indirect MR arthrography is a promising non-invasive technique in the evaluation of the glenoid labrum. (orig.) [Deutsch] Ziel: In frueheren Studien wurde gezeigt, dass die intravenoese Injektion gadoliniumhaltiger Kontrastmittel zur Signalintensitaetssteigerung im Gelenkkavum fuehrt. In dieser Studie wurde erstmals diese Technik der indirekten MR-Arthrographie am Schultergelenk in der Diagnostik von Labrumlaesionen evaluiert. Methode: 28 Patienten mit klinischem Verdacht auf eine Verletzung des Labrum glenoidale und/oder der Rotatorenmanschette wurden prospektiv nach folgendem Protokoll an einem 1,5-Tesla-System mit einer Oberflaechen-Ringspule untersucht: 1. Native MR-Standard-Untersuchung mit

  4. Diagnostic performance of MR arthrography with anterior trans-subscapularis versus posterior injection approach for subscapularis tendon tears at 3.0 T

    Energy Technology Data Exchange (ETDEWEB)

    Jung, Joon-Yong; Jee, Won-Hee [Seoul St. Mary' s Hospital, College of Medicine, The Catholic University of Korea, Department of Radiology, Seoul (Korea, Republic of); Chun, Chang-Woo [Uijeongbu St. Mary' s Hospital, College of Medicine, The Catholic University of Korea, Department of Radiology, Uijeongbu-si, Gyeonggi-do (Korea, Republic of); Kim, Yang-Soo [Seoul St. Mary' s Hospital, College of Medicine, The Catholic University of Korea, Department of Orthopedic Surgery, Seoul (Korea, Republic of)

    2017-03-15

    To compare the diagnostic performance of shoulder magnetic resonance arthrography (MRA) with the anterior trans-subscapularis versus posterior injection approach to diagnose subscapularis tendon (SCT) tears. One hundred and sixty-seven arthroscopically confirmed patients (84 anterior and 83 posterior approaches) were included. Two readers retrospectively scored SCT tears. Proportions of correctly graded tears between MR arthrography and arthroscopy were calculated. Retrospective error analysis was performed. The sensitivity and specificity were 80 % (24/30) and 72 % (39/54) by reader 1, 73 % (22/30) and 76 % (41/54) by reader 2 in the anterior approach, and 86 % (30/35) and 79 % (38/48) by reader 1, 80 % (28/35) and 88 % (42/48) by reader 2 in the posterior approach, respectively. There were no significant differences in sensitivity and specificity between the two groups. Proportions of correctly graded tears of both readers were 48 % and 36 % in the anterior approach, and 70 % and 68 % in the posterior approach, respectively. The intratendinous collection of contrast material was not statistically significantly different between anterior (n = 8) and posterior (n = 3) approach group. For the MRA diagnosis of SCT tears, there was no significant difference between the anterior trans-subscapularis and the posterior approach. (orig.)

  5. Findings of the subcoracoid bursa on MR arthrography and their clinical significance

    Energy Technology Data Exchange (ETDEWEB)

    Hirano, Yoshinori [Akita Municipal Hospital (Japan); Sashi, Ryuji; Izumi, Junichi; Watarai, Jiroh; Itoi, Eiji [Akita Univ. (Japan). School of Medicine

    2002-10-01

    We studied visualization of the subcoracoid bursa by conducting a retrospective analysis of the MR arthrograms of 101 shoulders with surgical confirmation. MR arthrography showed the subcoracoid bursa in 28 shoulders, among which the bursa was revealed by inadvertent direct injection of contrast material into the bursa in 10 shoulders. Of the remaining 18 shoulders, 16 shoulders had rotator cuff tears, one had shoulder instability, and one had dislocation of the long head of the biceps tendon. Both the subcoracoid and subscapularis bursae are located in the subcoracoid space. The subcoracoid bursa does not communicate with the subscapularis bursa, but occasionally communicates with the subacromial-subdeltoid bursa. On MR arthrography, contrast material in the subcoracoid bursa indicates a pathologic condition such as rotator cuff tear. Careful examination of the subcoracoid bursa on MR arthrography helps to achieve better assessment of the rotator cuff. (author)

  6. Experience of CT arthrography of the cruciate ligaments of the knee

    Energy Technology Data Exchange (ETDEWEB)

    Reiser, M.; Rupp, N.; Karpf, P.M.; Feuerbach, S.; Paar, O.

    1982-10-01

    CT arthrography of the cruciate ligaments in 512 patients has shown that this new procedure provides a reproducible method for demonstrating these ligaments and for making a confident diagnosis of abnormalities. A classification of cruciate ligament lesions into five injury types was introduced in order to distinguish the morphological CT findings. The indication for CT arthrography of the cruciate ligaments is uncertainty after clinical examination. CT can help materially in deciding on treatment and in planning surgery, particularly in cases of possible knee joint instability with a long history, in recent cases with marked muscle spasm and in patients with isolated anterior ligament rupture.

  7. Resonances

    DEFF Research Database (Denmark)

    an impetus or drive to that account: change, innovation, rupture, or discontinuity. Resonances: Historical Essays on Continuity and Change explores the historiographical question of the modes of interrelation between these motifs in historical narratives. The essays in the collection attempt to realize...... theoretical consciousness through historical narrative ‘in practice’, by discussing selected historical topics from Western cultural history, within the disciplines of history, literature, visual arts, musicology, archaeology, philosophy, and theology. The title Resonances indicates the overall perspective...

  8. Arthrography of the lumber facet joint and facet block

    Energy Technology Data Exchange (ETDEWEB)

    Cho, Hee Kyung; Chung, Tae Sub; Kim, Young Soo; Park, Hyung Chun; Moon, Jae Ho; Suh, Jung Ho; Kim, Dong Ik [Yonsei University College of Medicine, Seoul (Korea, Republic of)

    1988-12-15

    In spite of numerous clinical and patho-anatomical studied made in the past, there are still different opinions concerning the mechanism of low back pain. We have focused attention on the posterior structures as an alternative source of low back pain with sciatica. So we have studied and analyzed the finding of arthrography of facet joint and effect of the injection of methyprednisolone acetate suspension (Depomedrol) 20mg into the each facet joint. Our results are as follows: 1. Abnormal findings of facet joint arthrogram were degenerative osteoarthritis of facet joint (70.5%), synovial cyst (11.8%), accessory bone (11.8%), and spondylolysis (5.9%). 2. The mean facet angulations of patients of facet syndrome were abnormal on lower lumbar facet joint in 9 of 13 cases (69.2%). 3. On initial assessment, 11 of 17 cases (64.7%) showed complete relief and one month later, 6 of 11 cases (35.3%) showed continuous relief, after steroid injection.

  9. Diagnosis of classification of SLAP lesion with MR arthrography

    Energy Technology Data Exchange (ETDEWEB)

    Yamaguchi, Takayuki; Eto, Masao; Tomonaga, Tadashi; Takahara, Kazuhiro; Kushida, Manabu; Inatomi, Kenshiro; Akase, Keisuke; Wake, Satoshi; Shindo, Hiroyuki [Nagasaki Univ. (Japan). School of Medicine

    2003-03-01

    To determine the accuracy of MR Arthrography (MRA) in the classification of super labrum anterior posterior (SLAP) lesions, we investigated 15 patients (15 men, average 27.5 years) who underwent MRA before arthroscopic operation from 1998 to 2001. Based on the Snyder's classification, we defined the diagnostic criteria for classification of SLAP lesion on MRA: Type I shows irregularity of the labrum, without evidence of detachment from the superior glenoid rim. Type II shows complete detachment of the bicipital-labral complex. Type III shows detachment and inferior displacement of the superior labrum. Type IV shows Gd-DTPA dissecting into the biceps tendon. MRA findings correlated with arthroscopic findings. In MRA, 4 patients were diagnosed as type I, 10 type II, and 1 type IV. But in surgical findings, 3 out of the 4 patients diagnosed as type I were type II, and 3 out of the 10 patients (type II) were type I. MRA had a sensitivity of 25%, specificity of 73%, accuracy of 60% in type I, and sensitivity of 70%, specificity of 40%, accuracy of 60% in type II. The MRA classification corresponded with those of arthroscopy in 9 out of 15 patients (60%). MRA is a useful technique in the diagnosis of SLAP lesion, but classification is still difficult. (author)

  10. Comparison of MRI and arthrography in the preoperative work up of Legg-Calve-Perthes disease; Bilan preoperatoire des osteochondrites de hanches: comparaison de l'arthrographie et de l'IRM avec des cliches en abduction

    Energy Technology Data Exchange (ETDEWEB)

    Boyer, C.; Leclet, H.; Sutter, B.; Delforge, P.M. [Institut Calot, Service de l' Unite d' Imagerie de l' Appareil Locomoteur, 62 - Berck sur Mer (France)

    2001-05-01

    Purpose. Comparison between conventional arthrography and MRI in the preoperative work up of Legg-Calve-Perthes disease. Material and methods. We studied 17 children (18 hips) who had arthrography and MRI (open-magnet configuration) the same day. Coronal and sagittal T1 weighted were realised with the hip in neutral position. Additional coronal T1 weighted with abduction of the hip were obtained. Two readers analysed individually MRI and arthrographic findings: shape of femoral head, index of Heyman (antero-external covering), came effect, re-centering of femoral head and quality of examination. Results. No statistical difference between MRI and arthrography could be noted-exception made for the index of Heyman. Conclusion. MRI can replace arthrography in Legg-Calve-Perthes disease. (authors)

  11. Feasibility of ultrasound-guided intraarticular contrast injection for MR arthrography

    Energy Technology Data Exchange (ETDEWEB)

    Baek, Soo Jin; Lee, Jong Min; Kang, Duck Sick [Kyungpook National University School of Medicine, Daegu (Korea, Republic of)

    2005-07-15

    To assess the feasibility of ultrasound-guided intraarticular contrast injection using the posterior approach for MR arthrography. Between June 2002 and October 2004, 132 patients (29 female, 103 male: mean age, 33.6 years) underwent ultrasound-guided intraarticular contrast media injection (40 ml saline + 10 ml 2% lidocaine + 0.2 ml gadopentetate dimeglumine + 0.4 ml epinephrine) for MR arthrography. The patients were classified into four groups, viz. the no leakage group, the minor leakage with successful intraarticular injection group, the major leakage with unsuccessful intraarticular injection group, and the injection failure group. The 'no leakage' and 'minor leakage' groups were considered to be technical successes, while the 'major leakage' and 'injection failure' groups were regarded as technical failures. The technical success rate of ultrasound-guided intraarticular contrast injection using the posterior approach for MR Arthrography was 99.2% (131/132 patients) and one patients 0.7% (1/132 patients) was included in the 'major leakage' group. Ultrasound-guided intraarticular contrast injection using the posterior approach for MR arthrography was feasible with a high success rate.

  12. Direct shoulder MR arthrography using low field scanner for assessment of labral tears to assess scan reliability in claustrophobic patients

    OpenAIRE

    Heba Ibrahim Ali; Hossam Abdelkader

    2016-01-01

    Purpose: Shoulder instability is a common condition that primarily affects young active people. MR arthrography (MRA) has enhanced the capability of conventional MRI in assessing intra articular structures. Claustrophobic patients cannot tolerate scanning by closed magnet machines, so the aim of our study was to assess the labral tears by direct MR arthrography of the shoulder in claustrophobic patients using low field 0.32T machine and to evaluate the reliability of this scanning protocol co...

  13. Reduction of Pt2+ species in model Pt-CeO2 fuel cell catalysts upon reaction with methanol

    Science.gov (United States)

    Neitzel, Armin; Johánek, Viktor; Lykhach, Yaroslava; Skála, Tomáš; Tsud, Nataliya; Vorokhta, Mykhailo; Matolín, Vladimír; Libuda, Jörg

    2016-11-01

    The stability of atomically dispersed Pt2+ species on the surface of nanostructured CeO2 films during the reaction with methanol has been investigated by means of synchrotron radiation photoelectron spectroscopy and resonant photoemission spectroscopy. The isolated Pt2+ species were prepared at low Pt concentration in Pt-CeO2 film. Additionally, Pt2+ species coexisting with metallic Pt particles were prepared at high Pt concentration. We found that adsorption of methanol yields similar decomposition products regardless of Pt concentration in Pt-CeO2 films. A small number of oxygen vacancies formed during the methanol decomposition can be replenished in the Pt-CeO2 film with low Pt concentration by diffusion of oxygen from the bulk. In the presence of supported Pt particles, a higher number of oxygen vacancies leads to a partial reduction of the Pt2+ species. The isolated Pt2+ species are reduced under rather strongly reducing conditions only, i.e. during annealing under continuous exposure to methanol. Reduction of isolated Pt2+ species results in the formation of ultra-small Pt particles containing around 25 atoms per particle or less. Such ultra-small Pt particles demonstrate excellent stability against sintering during annealing of Pt-CeO2 film with low Pt concentration under reducing conditions.

  14. MR arthrography: pharmacology, efficacy and safety in clinical trials

    Energy Technology Data Exchange (ETDEWEB)

    Schulte-Altedorneburg, G.; Gebhard, M.; Wohlgemuth, W.A.; Fischer, W.; Zentner, J.; Bohndorf, K. [Department of Radiology, Klinikum Augsburg, Stenglinstrasse 2, 86156 Augsburg (Germany); Wegener, R.; Balzer, T. [Clinical Development Diagnostics and Radiopharmaceuticals II, Schering AG, Berlin (Germany)

    2003-01-01

    A meta-analysis was carried out of clinical trials published between 1987 and 2001 in respect of the clinical pharmacology and safety as well as the diagnostic efficacy of gadolinium-DTPA (Gd-DTPA) for direct intra-articular injection before MRI examination.Design. Scientific papers (clinical, postmortem and experimental studies) and information from the manufacturer regarding intra-articular injection of Gd-DTPA that addressed questions of mode of action, optimal concentration and dose, elimination and safety were reviewed. Clinical studies were classified according to their study design. The sensitivity, specificity and accuracy of MR arthrography (MRA) were compared with a ''gold standard'' (arthroscopy, arthrotomy) and other radiological evidence for different joints.Results. Fifty-two clinical studies of the overall 112 studies addressed aspects of diagnostic efficacy of MRA in patients or in healthy volunteers. The shoulder was the most assessed joint (29 of 52 studies). Good (>80%) or even excellent (90-100%) sensitivity, specificity and accuracy were found for MRA in most indications, especially for the shoulder and knee joints and induced extension of rotator cuff lesions, labrum abnormalities and postoperative meniscal tears. Two millimoles per liter has proven to be the best concentration for intra-articular administration of Gd-DTPA. After passive complete diffusion from the joint within 6-24 h, complete and rapid renal elimination takes place after intra-articular injection. Local safety proved to be excellent after intra-articular administration of Gd-DTPA. Regarding systemic tolerance almost no side effects have been reported, but the same safety considerations apply for intra-articular administration of Gd-DTPA as for intravenous injection.Conclusions. The diagnostic efficacy of intra-articular MRA in most clinical conditions affecting major joints is greater than that of plain MRI. In some diagnostic problems MRA achieves almost

  15. Shoulder arthrography: comparison of morbidity after use of various contrast media

    Energy Technology Data Exchange (ETDEWEB)

    Hall, F.M.; Goldberg, R.P.; Wyshak, G.; Kilcoyne, R.F.

    1985-02-01

    This prospective study compares immediate and delayed patient discomfort in 177 patients following shoulder arthrography using intraarticular combinations of metrizamide, meglumine/sodium diatrizoate, meglumine diatrizoate, lidocaine, epinephrine, and air. Patients receiving conventional ionic monomeric positive contrast media had a 60% (90/150) incidence of moderate or severe delayed exacerbation of their baseline symptoms; only 14% (3/21) of patients receiving metrizamide, a nonionic contrast medium had similar levels of postprocedural discomfort. Morbidity was somewhat diminished with the use of double-contrast (45%, 34/75) rather than single-contrast (75%, 56/75) examinations, and with avoidance of sodium-containing contrast agents or epinephrine. Nonionic or monovalent polymeric contrast media, despite their present high cost, may be the agents of choice if single-contrast arthrography is performed in joints associated with a high incidence of postprocedural pain.

  16. Normal anatomy and common labral lesions at MR arthrography of the shoulder

    Energy Technology Data Exchange (ETDEWEB)

    Robinson, G. [Royal United Hospital, Bath (United Kingdom)]. E-mail: gro@doctors.org.uk; Ho, Y. [Hamilton Health Sciences, Hamilton, Henderson Hospital, McMaster University, Hamilton (Canada); Finlay, K. [Hamilton Health Sciences, Hamilton, Henderson Hospital, McMaster University, Hamilton (Canada); Friedman, L. [Hamilton Health Sciences, Hamilton, Henderson Hospital, McMaster University, Hamilton (Canada); Harish, S. [Hamilton Health Sciences, Hamilton, Henderson Hospital, McMaster University, Hamilton (Canada)

    2006-10-15

    MR arthrography of the shoulder is the most accurate imaging modality in demonstrating abnormalities of the glenoid labrum and associated structures. Tears of the labrum, the capsule or the gleno-humeral ligaments can lead to pain, catching, popping or instability. The anatomy of this region is complex. We present the normal anatomy of the glenoid labrum, biceps anchor and gleno-humeral ligaments together with their normal variants and then describe common labral-ligamentous pathologies.

  17. Intrinsic carpal ligaments on MR and multidetector CT arthrography: comparison of axial and axial oblique planes

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Ryan K.L.; Griffith, James F.; Ng, Alex W.H.; Law, Eric K.C. [The Chinese University of Hong Kong, Department of Imaging and Interventional Radiology, Prince Of Wales Hospital, Hong Kong (China); Tse, W.L.; Wong, Clara W.Y.; Ho, P.C. [The Chinese University of Hong Kong, Department of Orthopedics and Traumatology, Prince Of Wales Hospital, Hong Kong (China)

    2017-03-15

    To compare axial and oblique axial planes on MR arthrography (MRA) and multidetector CT arthrography (CTA) to evaluate dorsal and volar parts of scapholunate (SLIL) and lunotriquetral interosseous (LTIL) ligaments. Nine cadaveric wrists of five male subjects were studied. The visibility of dorsal and volar parts of the SLIL and LTIL was graded semi-quantitatively (good, intermediate, poor) on MRA and CTA. The presence of a ligament tear was determined on arthrosocopy and sensitivity, specificity and accuracy of tear detection were calculated. Oblique axial imaging was particularly useful for delineating dorsal and volar parts of the LTIL on MRA with overall 'good' visibility increased from 11 % to 78 %. The accuracy of MRA and CTA in revealing SLIL and LTIL tear was higher using the oblique axial plane. The overall accuracy for detecting SLIL tear on CTA improved from 94 % to 100 % and from 89 % to 94 % on MRA; the overall accuracy of detecting LTIL tear on CTA improved from 89 % to 100 % and from 72 % to 89 % on MRA Oblique axial imaging during CT and MR arthrography improves detection of tears in the dorsal and volar parts of both SLIL and LTIL. (orig.)

  18. Reproducibility of X-rays and CT arthrography in SLAC, SNAC, SCAC wrists.

    Science.gov (United States)

    Belhaouane, R; Lebeau, N; Maes-Clavier, C; Hustin, C; Krief, E; Bonnaire, B; Warin, M; Rotari, V; David, E

    2016-12-01

    The purpose of this study was to assess the inter-observer and intra-observer reproducibility of the interpretation of CT arthrography and plain X-rays for scapholunate advanced collapse (SLAC), scaphoid non-union advanced collapse (SNAC) and scaphoid chondrocalcinosis advanced collapse (SCAC) wrist conditions, as well as the clinical relevance of these imaging modalities. The CT and X-rays images were reviewed twice in a blinded and randomized manner by two experienced orthopedic surgeons specialized in hand surgery, two orthopedic surgery residents and two experienced radiologists specialized in bone and joint imaging. Cohen's kappa and Fleiss' kappa coefficients were used to analyze the reproducibility of interpretation of the radiological examinations. With CT arthrography, the overall diagnosis was often a problem, in terms of both inter- or intra-observer reproducibility. The assessment of the joint line appeared to be fairly reproducible for each observer but was poorly reproducible between different observers. Plain X-rays are not sufficient to assess cartilage quality in degenerative wrist disease. CT arthrography is a reliable examination, but its interpretation is not always standardized. Diagnostic arthroscopy may be justified in doubtful cases.

  19. Abduction and external rotation (ABER) MR arthrography of the shoulder. Benefits and limitations

    Energy Technology Data Exchange (ETDEWEB)

    Mostafa, A.; Gokan, Takehiko; Munechika, Hirotsugu; Ogawa, Takashi [Showa Univ., Tokyo (Japan). School of Medicine; El-Feky, A.A.

    2001-12-01

    The purpose of this study was to show the benefits and limitations of using abduction and external rotation (ABER) positions of the arm during MR arthrography of the shoulder in the evaluation of the rotator-cuff tendon, the capsulolabral complex and the shoulder joint after surgery. Forty-seven patients complaining of either shoulder instability, chronic shoulder pain, pain of unknown cause or pain following shoulder surgery were studied using the direct MR arthrography technique in both the standard neutral position with the arm adducted as well as with the arm in the ABER position. A correlation was obtained between the MR arthrography findings and the surgical findings in 10 reports and clinical presentations of the examined patients. Three patients [6%] were unable to perform ABER positioning. ABER oblique axial images were better than standard oblique coronal images in revealing undersurface tears of the rotator cuff particularly of the grade I type. Four tears were missed in standard images. Oblique axial images were better than standard axial images in demonstrating non-displaced anterior labral tears. One tear was missed and two tears were suspected in the standard images. Oblique axial images were less sensitive than oblique coronal images in the diagnosis of superior labral tears. Two tears were missed in ABER images. The ABER oblique axial MR arthrogram is a useful adjunct to the standard axial and oblique coronal MR arthrograms for assessment of capsulolabral abnormalities and rotator-cuff tendon tears despite some limitations. (author)

  20. CT arthrography and virtual arthroscopy in the diagnosis of the anterior cruciate ligament and meniscal abnormalities of the knee joint

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Whal; Chung, Jin-Wook; Kang, Heung-Sik; Hong, Sung-Hwan; Choi, Ja-Young [Seoul National University, Seoul (Korea, Republic of); Kim, Ho-Sung; Kim, Seok-Jung; Kim, Hyung-Ho [Aeromedical Center, Seoul (Korea, Republic of)

    2004-03-15

    To determine the diagnostic accuracy of CT arthrography and virtual arthroscopy in the diagnosis of anterior cruciate ligament and meniscus pathology. Thirty-eight consecutive patients sho underwent CT arthrography and arthroscopy of the knee were included in this study. The ages of the patients ranged from 19 to 52 years and all of the patients were male. Sagittal, coronal, transverse and oblique coronal multiplanar reconstruction images were reformatted from CT arthrography. Virtual arthroscopy was performed from 6 standard views using a volume rendering technique. Three radiologists analyzed the MPR images and two orthopedic surgeons analyzed the virtual arthroscopic images. The sensitivity and specificity of CT arthrography for the diagnosis of anterior cruciate ligament abnormalities were 87.5%-100% and 93.3%-96.7%, respectively and those for meniscus abnormalities were 91.7%-100% and 98.1%, respectively. The sensitivity and specificity of virtual arthroscopy for the diagnosis of anterior cruciate ligament abnormalities were 87.5% and 83.3%-90%, respectively, and those for meniscus abnormalities were 83.3%-87.5% and 96.1-98.1%, respectively. CT arthrography and virtual arthroscopy showed good diagnostic accuracy for anterior cruciate ligament and meniscal abnormalities.

  1. Diagnostic performance of CT-arthrography and 1.5T MR-arthrography for the assessment of glenohumeral joint cartilage: a comparative study with arthroscopic correlation

    Energy Technology Data Exchange (ETDEWEB)

    Omoumi, Patrick [Cliniques Universitaires St Luc - Universite Catholique de Louvain, Department of Radiology, Brussels (Belgium); Lausanne University Hospital, Department of Radiology, Lausanne (Switzerland); Rubini, Alexandra; Berg, Bruno C. vande; Lecouvet, Frederic E. [Cliniques Universitaires St Luc - Universite Catholique de Louvain, Department of Radiology, Brussels (Belgium); Dubuc, Jean-Emile [Cliniques Universitaires St Luc - Universite Catholique de Louvain, Department of Orthopedic Surgery, Brussels (Belgium)

    2015-04-01

    To compare the diagnostic performance of multi-detector CT arthrography (CTA) and 1.5-T MR arthrography (MRA) in detecting hyaline cartilage lesions of the shoulder, with arthroscopic correlation. CTA and MRA prospectively obtained in 56 consecutive patients following the same arthrographic procedure were independently evaluated for glenohumeral cartilage lesions (modified Outerbridge grade ≥2 and grade 4) by two musculoskeletal radiologists. The cartilage surface was divided in 18 anatomical areas. Arthroscopy was taken as the reference standard. Diagnostic performance of CTA and MRA was compared using ROC analysis. Interobserver and intraobserver agreement was determined by κ statistics. Sensitivity and specificity of CTA varied from 46.4 to 82.4 % and from 89.0 to 95.9 % respectively; sensitivity and specificity of MRA varied from 31.9 to 66.2 % and from 91.1 to 97.5 % respectively. Diagnostic performance of CTA was statistically significantly better than MRA for both readers (all p ≤ 0.04). Interobserver agreement for the evaluation of cartilage lesions was substantial with CTA (κ = 0.63) and moderate with MRA (κ = 0.54). Intraobserver agreement was almost perfect with both CTA (κ = 0.94-0.95) and MRA (κ = 0.83-0.87). The diagnostic performance of CTA and MRA for the detection of glenohumeral cartilage lesions is moderate, although statistically significantly better with CTA. (orig.)

  2. Following the molecular motion of near-resonant excited CO on Pt(111): A simulated x-ray photoelectron diffraction study based on molecular dynamics calculations

    Science.gov (United States)

    Greif, Michael; Nagy, Tibor; Soloviov, Maksym; Castiglioni, Luca; Hengsberger, Matthias; Meuwly, Markus; Osterwalder, Jürg

    2015-01-01

    A THz-pump and x-ray-probe experiment is simulated where x-ray photoelectron diffraction (XPD) patterns record the coherent vibrational motion of carbon monoxide molecules adsorbed on a Pt(111) surface. Using molecular dynamics simulations, the excitation of frustrated wagging-type motion of the CO molecules by a few-cycle pulse of 2 THz radiation is calculated. From the atomic coordinates, the time-resolved XPD patterns of the C 1s core level photoelectrons are generated. Due to the direct structural information in these data provided by the forward scattering maximum along the carbon-oxygen direction, the sequence of these patterns represents the equivalent of a molecular movie. PMID:26798798

  3. Following the molecular motion of near-resonant excited CO on Pt(111: A simulated x-ray photoelectron diffraction study based on molecular dynamics calculations

    Directory of Open Access Journals (Sweden)

    Michael Greif

    2015-05-01

    Full Text Available A THz-pump and x-ray-probe experiment is simulated where x-ray photoelectron diffraction (XPD patterns record the coherent vibrational motion of carbon monoxide molecules adsorbed on a Pt(111 surface. Using molecular dynamics simulations, the excitation of frustrated wagging-type motion of the CO molecules by a few-cycle pulse of 2 THz radiation is calculated. From the atomic coordinates, the time-resolved XPD patterns of the C 1s core level photoelectrons are generated. Due to the direct structural information in these data provided by the forward scattering maximum along the carbon-oxygen direction, the sequence of these patterns represents the equivalent of a molecular movie.

  4. High origin of the anterior band of the inferior glenohumeral ligament: MR arthrography with anatomic and histologic correlation in cadavers

    Energy Technology Data Exchange (ETDEWEB)

    Ramirez Ruiz, Francisco Alejandro [University of California and VA healthcare system, Department of Radiology, Musculoskeletal Division, San Diego, CA (United States); University of California and VA healthcare system, San Diego, CA (United States); Hospital Pablo Tobon Uribe, Departamento de Radiologia, Medellin (Colombia); Baranski Kaniak, Beatriz Cristina; Trudell, Debra; Resnick, Donald L. [University of California and VA healthcare system, Department of Radiology, Musculoskeletal Division, San Diego, CA (United States); Haghighi, Parviz [University of California and VA healthcare system, Department of Radiology, Musculoskeletal Division, San Diego, CA (United States); University of California San Diego, VA Healthcare System Dan Diego, Department of Pathology, San Diego, CA (United States)

    2012-05-15

    The anterior band of the inferior glenohumeral ligament has been described to arise from the anteroinferior labrum, but we have observed that in some persons its origin is from the anterior or anterosuperior labrum, creating diagnostic difficulties. Ten fresh unembalmed cadaveric shoulders underwent magnetic resonance arthrography (MRA) using a posterior approach with a 1.5 T GE magnet, with the following sequences: T1-weighted fast spin-echo in axial, coronal and sagittal planes, and T1 fat-suppressed spin-echo in the axial plane (TR/TE 600/20, section thickness 2.5 mm, 0.5 mm interslice space, number of signals acquired, two, field of view 12 x 12 cm, and matrix 512 x 256 pixels). Following imaging, the shoulders were frozen and later sectioned using a band saw into 3-mm sections corresponding to the axial imaging plane. Histological analysis was also performed to determine the origin of the anterior band. Four of the ten shoulders had an origin of the anterior band above or at the 3 o'clock position: one at the 1 o'clock position, two at the 2 o'clock position, and one at the 3 o'clock position. In another shoulder, the anterior band of the inferior glenohumeral ligament originated from the middle glenohumeral ligament, and in five other shoulders, the anterior band originated from the anteroinferior labrum as has been described in the literature. This finding is of clinical significance as a high origin of the anterior band of the inferior glenohumeral ligament leads to MR arthrographic finding that can simulate those of labral tears or detachments. (orig.)

  5. Freehand direct arthrography of the shoulder using near real-time guidance in an open 1.0-T MRI scanner

    Energy Technology Data Exchange (ETDEWEB)

    Wybranski, Christian [University Hospital of Cologne, Institute of Diagnostic and Interventional Radiology, Cologne (Germany); Adamchic, Ilya; Ricke, Jens; Fischbach, Frank; Fischbach, Katharina [Otto-von-Guericke University Medical School, Department of Radiology and Nuclear Medicine, Magdeburg (Germany); Roehl, Friedrich-Wilhelm [Otto-von-Guericke University Medical School, Institute of Biometry and Medical Informatics, Magdeburg (Germany)

    2017-01-15

    To assess the technical success and duration of magnetic resonance imaging (MRI)-guided freehand direct shoulder arthrography (FDSA) with near real-time imaging implemented in a routine shoulder MRI examination on an open 1.0-T MRI scanner, and to assess the learning curve of residents new to this technique. An experienced MRI interventionalist (the expert) performed 125 MRI-guided FDSA procedures, and 75 patients were treated by one of three residents without previous experience in MRI-guided FDSA. Technical success rate and duration of MRI-guided FDSA of the expert and the residents were compared. The residents' learning curves were assessed. The occurrence of extra-articular deposition and leakage of contrast media from the puncture site and the subsequent impairment of image interpretation were retrospectively analyzed. Overall technical success was 97.5 %. The expert needed overall fewer puncture needle readjustments and was faster at puncture needle positioning (p < 0.01). The learning curve of the residents, however, was steep. They leveled with the performance of the expert after ∼ 15 interventions. With a minimal amount of training all steps of MRI-guided FDSA can be performed in ≤10 min. Magnetic resonance-guided FDSA in an open 1.0-T MRI scanner can be performed with high technical success in a reasonably short amount of time. Only a short learning curve is necessary to achieve expert level. (orig.)

  6. Comparisons of the Various Partial-Thickness Rotator Cuff Tears on MR Arthrography and Arthroscopic Correlation

    Energy Technology Data Exchange (ETDEWEB)

    Chun, Kyung Ah; Kim, Min Sung; Kim, Young Joo [Catholic University of Korea Uijeongbu St.Mary' s Hospital, Uijeongbu (Korea, Republic of)

    2010-10-15

    To assess the diagnostic performance of MR arthrography in the diagnosis of the various types of partial-thickness rotator cuff tears by comparing the MR imaging findings with the arthroscopic findings. The series of MR arthrography studies included 202 patients consisting of 100 patients with partial-thickness rotator cuff tears proved by arthroscopy and a control group of 102 patients with arthroscopically intact rotator cuffs, which were reviewed in random order. At arthroscopy, 54 articularsided, 26 bursal-sided, 20 both articular- and bursal-sided partial-thickness tears were diagnosed. The MR arthrographies were analyzed by two radiologists for articular-sided tears, bursal-sided tears, and both articular- and bursal-sided tears of the rotator cuff. The sensitivity and specificity of each type of partial-thickness tears were determined. Kappa statistics was calculated to determine the interand intra-observer agreement of the diagnosis of partial-thickness rotator cuff tears. The sensitivity and specificity of the various types of rotator cuff tears were 85% and 90%, respectively for articular-sided tears, 62% and 95% for bursal- sided tears, as well as 45% and 99% for both articular- and bursal-sided tears. False-negative assessments were primarily observed in the diagnosis of bursal-sided tears. Conversely, both articular- and bursal-sided tears were overestimated as full-thickness tears. Inter-observer agreement was excellent for the diagnosis of articular-sided tears (k = 0.70), moderate (k = 0.59) for bursal-sided tears, and fair (k = 0.34) for both articular- and bursal-sided tears, respectively. Intra-observer agreement for the interpretation of articular- and bursal-sided tears was excellent and good, respectively, whereas intra-observer agreement for both articular- and bursal-sided tears was moderate. MR arthrography is a useful diagnostic tool for partial-thickness rotator cuff tears, but has limitations in that it has low sensitivity in bursal- and

  7. A study of the anatomy and injection techniques of the ovine stifle by positive contrast arthrography, computed tomography arthrography and gross anatomical dissection.

    Science.gov (United States)

    Vandeweerd, Jean-Michel; Kirschvink, Nathalie; Muylkens, Benoit; Depiereux, Eric; Clegg, Peter; Herteman, Nicolas; Lamberts, Matthieu; Bonnet, Pierre; Nisolle, Jean-Francois

    2012-08-01

    Although ovine stifle models are commonly used to study osteoarthritis, meniscal pathology and cruciate ligament injuries and repair, there is little information about the anatomy of the joint or techniques for synovial injections. The objectives of this study were to improve anatomical knowledge of the synovial cavities of the ovine knee and to compare intra-articular injection techniques. Synovial cavities of 24 cadaver hind limbs from 12 adult sheep were investigated by intra-articular resin, positive-contrast arthrography, computed tomography (CT) arthrography and gross anatomical dissection. Communication between femoro-patellar, medial femoro-tibial and lateral femoro-tibial compartments occurred in all cases. The knee joint should be considered as one synovial structure with three communicating compartments. Several unreported features were observed, including a communication between the medial femoro-tibial and lateral femoro-tibial compartments and a latero-caudal recess of the lateral femoro-tibial compartment. No intermeniscal ligament was identified. CT was able to define many anatomical features of the stifle, including the anatomy of the tendinous synovial recess on the lateral aspect of the proximal tibia under the combined tendon of the peroneus tertius, extensor longus digitorum and extensor digiti III proprius. An approach for intra-articular injection into this recess (the subtendinous technique) was assessed and compared with the retropatellar and paraligamentous techniques. All three injection procedures were equally successful, but the subtendinous technique appeared to be most appropriate for synoviocentesis and for injections in therapeutic research protocols with less risk of damaging the articular cartilage.

  8. Comparison of Plain MRI and MR Arthrography in the Evaluation of Lateral Ligamentous Injury of the Ankle Joint

    Directory of Open Access Journals (Sweden)

    Mei-Chun Chou

    2006-01-01

    Conclusion: For evaluating ankle disability, using plain MRI alone is not adequate for correctly detecting lateral collateral ligamentous injury of the ankle joint. MR arthrography improves the sensitivity and the accuracy for ATaF and CF ligament injuries. It also helps in assessing coexisting pathologic lesions of ankle joints, especially impingement syndromes and osteochondral lesions, and provides more information for therapeutic decision making.

  9. Evaluation of patellar cartilage surface lesions: comparison of CT arthrography and fat-suppressed FLASH 3D MR imaging

    Energy Technology Data Exchange (ETDEWEB)

    Daenen, B.R.; Ferrara, M.A.; Marcelis, S.; Dondelinger, R.F. [Department of Medical Imaging, University Hospital Sart-Tilman, Liege (Belgium)

    1998-07-01

    The aim of this study was to evaluate the sensitivity and specificity of fat-suppressed fast low-angle shot (FLASH) 3D MR imaging in the detection of patellar cartilage surface lesions in comparison with CT arthrography. Fifty patients, with or without symptoms of chondromalacia, were prospectively examined by CT arthrography and fat-suppressed 3D gradient-echo MR imaging. All MR examinations were evaluated by three observers, two of them reaching a consensus interpretation. The lesions were graded according to their morphology and their extent. The CT arthrography was considered as the reference examination. For both sets of observers, the final diagnosis of chondromalacia was obtained in 92.5 %. The specificity was 60 % on a patient-by-patient basis. Fissures were missed in 83 and 60 %, respectively, but were isolated findings only in 2.5 % of the cases. Considering ulcers involving more than 50 % of the cartilage thickness, 65 and 88 %, respectively, were recognized. Fat-suppressed FLASH 3D is an adequate pulse sequence for the detection of patellar cartilage ulcers. It can be applied on a routine clinical basis, but it does not show as many fissures as CT arthrography and is less precise for grading of lesions. (orig.) With 4 figs., 3 tabs., 21 refs.

  10. C-arm flat-panel CT arthrography of the shoulder: Radiation dose considerations and preliminary data on diagnostic performance

    Energy Technology Data Exchange (ETDEWEB)

    Guggenberger, Roman; Ulbrich, Erika J.; Kaelin, Pascal; Pfammatter, Thomas; Alkadhi, Hatem; Andreisek, Gustav [University Hospital Zurich, Institute of Diagnostic and Interventional Radiology, Zuerich (Switzerland); Dietrich, Tobias J. [Balgrist University Hospital, Department of Radiology, Zurich (Switzerland); Scholz, Rosemarie; Koehler, Christoph; Elsaesser, Thilo [Siemens Healthcare GmbH, Business Area Advanced Therapies, Forchheim (Germany); Le Corroller, Thomas [Aix-Marseille Universite, CNRS, ISM UMR 7287, Marseille (France); Radiology Department, APHM, Marseille (France)

    2017-02-15

    To investigate radiation dose and diagnostic performance of C-arm flat-panel CT (FPCT) versus standard multi-detector CT (MDCT) shoulder arthrography using MRI-arthrography as reference standard. Radiation dose of two different FPCT acquisitions (5 and 20 s) and standard MDCT of the shoulder were assessed using phantoms and thermoluminescence dosimetry. FPCT arthrographies were performed in 34 patients (mean age 44 ± 15 years). Different joint structures were quantitatively and qualitatively assessed by two independent radiologists. Inter-reader agreement and diagnostic performance were calculated. Effective radiation dose was markedly lower in FPCT 5 s (0.6 mSv) compared to MDCT (1.7 mSv) and FPCT 20 s (3.4 mSv). Contrast-to-noise ratios (CNRs) were significantly (p < 0.05) higher in FPCT 20-s versus 5-s protocols. Inter-reader agreements of qualitative ratings ranged between κ = 0.47-1.0. Sensitivities for cartilage and rotator cuff pathologies were low for FPCT 5-s (40 % and 20 %) and moderate for FPCT 20-s protocols (75 % and 73 %). FPCT showed high sensitivity (81-86 % and 89-99 %) for bone and acromioclavicular-joint pathologies. Using a 5-s protocol FPCT shoulder arthrography provides lower radiation dose compared to MDCT but poor sensitivity for cartilage and rotator cuff pathologies. FPCT 20-s protocol is moderately sensitive for cartilage and rotator cuff tendon pathology with markedly higher radiation dose compared to MDCT. (orig.)

  11. Comparison of Indirect MR Arthrography With Conventional MRI in the Diagnosis of Knee Pathologies in Patients With Knee Pain

    Directory of Open Access Journals (Sweden)

    Babaei Jandaghi

    2016-03-01

    Full Text Available Background Knee pain is a common problem in the general population. In order to determine the extent of the injury and the appropriate treatment, MRI provides the most accurate imaging method. This may be done through conventional MRI techniques or by injecting a contrast material (MR arthrography. Objectives The purpose of this study was to compare the diagnostic value of these two methods. Patients and Methods The study involved the diagnostic evaluation on 60 patients with knee pain who received treatment over the course of a one-year period. Referred patients were randomly divided into two groups: indirect MR arthrography was performed on one group, and conventional MRI was performed on the other group. Both groups then underwent arthroscopy. The results from both groups were compared with the arthroscopic findings. Results In all of the pathologies studied, the sensitivity, specificity, and the positive and negative predictive values were evaluated. A high rate of accuracy was found between MR arthrography and arthroscopy (P < 0.05 for all knee injuries, however a similar rate of accuracy between conventional MRI and arthroscopy was only seen in patients with damage to the posterior cruciate ligament (PCL, the tibio-femoral articular cartilage, and patella chondromalacia (P < 0.05. The highest rate of accuracy was seen in cases where indirect MR arthrography was used for the diagnosis of anterior cruciate ligament (ACL damage (K = 1. Conclusions Our results have shown that indirect MR arthrography had greater diagnostic accuracy in regards to the sensitivity, specificity, and positive and negative predictive values than conventional MRI in knee pathologies.

  12. MR arthrography of the shoulder: tolerance evaluation of four different injection techniques

    Energy Technology Data Exchange (ETDEWEB)

    Perdikakis, Evangelos; Drakonaki, Eleni; Karantanas, Apostolos [University Hospital, Department of Medical Imaging, Heraklion, Crete (Greece); Maris, Thomas [University Hospital, Department of Medical Physics, Heraklion, Crete (Greece)

    2013-01-15

    We sought to prospectively evaluate patients' pain perception and technical success of four different arthrographic techniques for shoulder MR arthrography. A total of 125 consecutive patients were referred for shoulder MR arthrography. The patients were randomly injected under fluoroscopic guidance (n{sub 1} = 37), with CT guidance using an anterior (n{sub 2} = 29) or a posterior approach (n{sub 3} = 32) and with ultrasound guidance (n{sub 4} = 27). For each patient, absolute periprocedural pain on a numerical rating pain scale (0 = ''no pain'', 10 = ''intolerable pain''), technical success of the method used, and reason for referral were recorded. The technical success rate was 100 % for all injection methods. The results regarding absolute periprocedural pain were as follows: fluoroscopic guidance showed a mean pain of 4.05 {+-} 1.24, CT anterior guidance demonstrated a mean pain of 3.87 {+-} 0.95, CT posterior guidance showed a mean pain of 1.59 {+-} 0.81, and ultrasound guidance a mean pain of 3.63 {+-} 1.12. A significant difference (p <.05) was observed for the posterior route under CT guidance. The mean pain level was significantly higher for older (> 51 year) female patients. No differences were found for the technical success rate of the aforementioned techniques. A CT-guided posterior approach seems to be a more comfortable method for the patient. (orig.)

  13. Double-contrast CT arthrography for the initial anterior dislocation of the shoulder

    Energy Technology Data Exchange (ETDEWEB)

    Suzuki, Katsunori; Minami, Akio; Takahara, Masatoshi; Kaneda, Kiyoshi (Hokkaido Univ., Sapporo (Japan). School of Medicine); Fukuda, Kimitaka; Takahashi, Shuji

    1994-09-01

    It is believed that age at the time of sustaining traumatic initial anterior dislocations of the shoulder may be greatly involved in the development of recurrent dislocations. The purpose of this study was to define lesion inside the shoulder joint using double-contrast arthrography in initial anterior dislocation. Thirty-three patients (33 shoulders) with a mean age of 32.5 years underwent double contrast-arthrography within 2 weeks after sustaining initial anterior dislocations. According to the age, the patients were divided into the [<=]30 year group (n=19) and the >30 year group (n=14). In the [<=]30 year group, 16 patients (84%) had an avulsion of the anterior capsule and glenoid labrum from the glenoid rim (Bankart lesion), as well as in the control group of 45 patients (46 shoulders) with recurrent dislocations. In the >30 year group, leakage of contrast material into the subacromial bursa and bone fracture of the tuberculum majus humeri were seen in 6 patients (43%), suggesting rupture of the tendon and joint capsule. Only 4 patients (29%) in this group had Bankart lesion. These findings suggest that adduction may be useless for Bankart lesion repair in younger patients, resulting in shoulder instability. Thus younger patients may be prone to develop recurrent dislocations of the shoulder. (N.K.).

  14. MR arthrography in calcific tendinitis of the shoulder: diagnostic performance and pitfalls

    Energy Technology Data Exchange (ETDEWEB)

    Zubler, Christoph; Mengiardi, Bernard; Schmid, Marius R.; Hodler, Juerg; Pfirrmann, Christian W.A. [University Hospital Balgrist, Radiology, Zurich (Switzerland); Jost, Bernhard [University Hospital Balgrist, Orthopedic Surgery, Zurich (Switzerland)

    2007-06-15

    The purpose was to assess the diagnostic performance of MR arthrography to diagnose calcific tendinitis of the shoulder and to assess the reasons for diagnostic errors. Standard MR arthrograms of 22 patients with calcific tendinitis and 61 controls were retrospectively analyzed by two independent and blinded radiologists. All cases were consecutively collected from a database. Conventional radiographs were available in all cases serving as gold standard. The supraspinatus was involved in 16, the infraspinatus in four and the subscapularis in two patients. All diagnostic errors were analyzed by two additional readers. Reader 1 correctly detected 12 of the 22 shoulders with and 42 of the 61 shoulders without calcific tendinitis (sensitivity 0.55, specificity 0.66). The corresponding values for reader 2 were 13 of 22 and 40 of 61 cases (sensitivity 0.59, specificity 0.69). Inter-rater agreement (kappa-value) was 0.42. Small size of the calcific deposits and isointensity compared to the surrounding tissue were the most important reasons for false negative results. Normal hypointense areas within the supraspinatus tendon substance and attachment were the main reason for false positive results. In conclusion, MR arthrography is insufficient in the diagnosis of calcific tendinitis. Normal hypointense parts of the rotator cuff may mimic calcific deposits and calcifications may not be detected when they are isointense compared to the rotator cuff. Therefore, MR imaging should not be interpreted without corresponding radiographs. (orig.)

  15. Glenohumeral position during CT arthrography with arthroscopic correlation: optimization of diagnostic yield

    Energy Technology Data Exchange (ETDEWEB)

    Simeone, F.J.; Gill, Corey M.; Torriani, Martin; Bredella, Miriam A. [Massachusetts General Hospital and Harvard Medical School, Division of Musculoskeletal Imaging and Intervention, Boston, MA (United States); Taneja, Atul K. [Hospital Israelita Albert Einstein, Hospital do Coracao (HCor) and Teleimagem, Musculoskeletal Imaging, Sao Paulo, SP (Brazil)

    2017-06-15

    To evaluate the diagnostic yield of two acquisitions of single-contrast CT arthrography (CTA) of the shoulder in internal, neutral, or external glenohumeral rotation with arthroscopic correlation. The CT study was obtained using two acquisitions (first the humerus positioned in maximum tolerated external rotation with the arm along the body and the second with the humerus in internal rotation with the palm placed flat on the table). Two independent readers blinded to the arthroscopic results evaluated the CTA images for labral tears, glenoid bone loss/fractures, and cartilage loss. For each CTA acquisition, sensitivity and specificity for detection of the aforementioned pathology were assessed. Inter-reader agreement was quantified by weighted k statistics. Sensitivity and specificity for detecting anteroinferior or posterior labral tears was highest with neutral rotation (sensitivity 91-100%, specificity 61-100%). For glenoid fracture, sensitivity (67%) was highest with external rotation and specificity (100%) was highest with internal rotation. For cartilage loss, sensitivity (64%) and specificity (89%) was highest with external rotation and neutral rotation, respectively. Neutral rotation showed high sensitivity and specificity for glenoid fractures and cartilage loss. Inter-reader agreement ranged from fair to very good. Neutral glenohumeral position in shoulder CT arthrography was adequately sensitive and specific for the detection of intra-articular pathology, avoiding the use of more than one acquisition. (orig.)

  16. Prothrombin time (PT)

    Science.gov (United States)

    PT; Pro-time; Anticoagulant-prothrombin time; Clotting time: protime; INR; International normalized ratio ... PT is measured in seconds. Most of the time, results are given as what is called INR ( ...

  17. Recent Advances in FePt Nanoparticles for Biomedicine

    Directory of Open Access Journals (Sweden)

    Yujuan Shi

    2015-01-01

    Full Text Available FePt nanoparticles have great potential for biomedical applications due to their superior characteristics, including superparamagnetism, resistance to oxidation, and high chemical stability. The present paper reviews the methods used to prepare FePt nanoparticles, surface modifications, and their applications in the biomedical field, such as biosensing, magnetic resonance imaging (MRI, targeted drug delivery, and therapy.

  18. [Double-contrast arthrography in chondropathia patellae--clinical and experimental study on pathogenesis and diagnosis (author's transl)].

    Science.gov (United States)

    Reichelt, A; Hehne, H J; Rau, W S; Schlageter, M

    1979-10-01

    This study is based on the evaluation of 250 arthrographies of the patellofemoral joint ("défilé" arthrographs in Ficat's terminology) which were performed because of clinical suspicion of chondropathia patellae and which could be controlled intraoperatively in 30 cases, as well as on examinations employing an etching paste as used in metallurgy and performed on 20 knee-joints of corpses. 46% of the arthrographies showed a ridge-shaped cartilaginous thickening which was not pre-modelled in the osseous structure and which separated the medial facette into a paramedian and a marginal segment and correlated with chondromalacia to a greater degree than patellar dysplasias or secondary osseous changes. This variant, which could not be detected by plain roentgenography, must be considered as a pre-arthrotic deformity on account of the high point-shaped pressure load on the ridge. The findings were fully confirmed by macroscopic examination of the postmortem material.

  19. Spiral CT arthrography of the knee: technique and value in the assessment of internal derangement of the knee

    Energy Technology Data Exchange (ETDEWEB)

    Berg, Vande B.C.; Lecouvet, F.E.; Maldague, B.; Malghem, J. [Department of Radiology, Cliniques Universitaires St. Luc, Universite Catholique de Louvain, Brussels (Belgium); Poilvache, P. [Department of Orthopedic Surgery, Cliniques Universitaires St. Luc, Universite Catholique de Louvain, Brussels (Belgium)

    2002-07-01

    Computed tomography imaging has achieved excellent multiplanar capability and submillimeter spatial resolution due to the development of the spiral acquisition mode and multidetector row technology. Multidetector spiral CT arthrography (CTA) yields valuable information for the assessment of internal derangement of the joints. This article focuses on the value of spiral CTA of the knee in the assessment of the meniscus, anterior cruciate ligament, and hyaline cartilage lesions. Advantages and disadvantages of spiral CTA with respect to MR imaging are presented. (orig.)

  20. Comparison of MR arthrography with arthroscopy of the hip for the assessment of intra-articular loose bodies

    Energy Technology Data Exchange (ETDEWEB)

    Neckers, Andrew C. [Columbus Radiology Corporation, Columbus, OH (United States); Polster, Joshua M.; Winalski, Carl S.; Sundaram, M. [The Cleveland Clinic Foundation, Diagnostic Radiology/A21, Cleveland, OH (United States); Krebs, Viktor E. [The Cleveland Clinic Foundation, Department of Orthopedic Surgery, Cleveland, OH (United States)

    2007-10-15

    To assess the specificity and sensitivity of MR arthrography of the hip in comparison with arthroscopy for the evaluation of intra-articular loose bodies. Over a 3-year period, 81 consecutive patients underwent a total of 82 hip arthroscopies by a single orthopedic surgeon for intractable hip pain. Of the 82 arthroscopies, 70 had pre-operative MR arthrograms. Of these, 57 were available for retrospective review, after which they were compared with the operative notes of the subsequent arthroscopies. Of 82 arthroscopies 16 (20%) demonstrated intra-articular loose bodies, while, in the study group, nine of 57 had loose bodies (16%). There was a total of seven discordant cases (five false negatives and two false positives). The sensitivity of MR arthrography for detection of intra-articular loose bodies was 44%, while the specificity was 96%. While the specificity of MR arthrography for the detection of intra-articular loose bodies was high (96%), the sensitivity was not nearly as good (44%). (orig.)

  1. Invisibility and PT symmetry

    OpenAIRE

    MOSTAFAZADEH, Ali

    2013-01-01

    PHYSICAL REVIEW A 87, 012103 (2013) Invisibility and PT symmetry Ali Mostafazadeh* Department of Mathematics, Koc¸ University, Sarıyer 34450, Istanbul, Turkey (Received 9 July 2012; published 3 January 2013) For a general complex scattering potential defined on a real line, we show that the equations governing invisibility of the potential are invariant under the combined action of parity and time-reversal (PT ) transformation. We determine the PT -symmetric as well as no...

  2. MORPHOLOGICAL AND SIGNAL CHARACTERISTICS OF ROTATOR CUFF TEARS ON CONVENTIONAL MRI AND MR ARTHROGRAPHY:COMPARING WITH GROSS ANATOMY AND HISTOPATHOLOGY

    Institute of Scientific and Technical Information of China (English)

    XU Jian-rong; DENG Xia; HUA Jia; CAI Wei-min; LI Lei; ZHU Jian-shan

    2005-01-01

    Objective To study the MR characterizations of supraspinatus and infraspinatus tendon lesions by comparing with gross anatomy and histopathology. Methods The study group consisted of 20 cadaver shoulders which were underwent the same imaging protocols of conventional MRI and MR arthrography. Results SE-T2WI images or MR arthrography respectively possessed of high specificity (95.6%, 100%), but low sensitivity (70.6%, 58.8%) for diagnosing rotator cuff tears. By uniting two images techniques, could remedy its limitations and would markedly increase the sensitivity (88.2%). There were many factors influencing the visualizations of partial thickness tears of rotator cuff on MR images, from which uppermost factors are tear extent, ruptured synovial capsule, scar and synovial proliferation. Conclusion MRI diagnoses of rotator cuff lesions (especially partial thickness tears) must carefully be estimated by combining T2WI images and MR arthrography.

  3. Light propagation through a PT-symmetric photonic-crystal.

    Science.gov (United States)

    Konotop, Vladimir V; Mantsyzov, Boris I

    2016-11-14

    Light propagation through a finite-width periodically modulated layer obeying parity-time (PT) symmetry is considered. We consider the configuration when the resonant conditions of mode coupling by the grating are satisfied. It is shown that the dependence of the transmission and reflection coefficients on the slab width has resonant character featuring strong amplification of reflected and transmitted waves with negative angles. The dependence of the scattering data on the gain-and-loss intensity also feature strong resonances near the PT-symmetry breaking point, when the slab strongly amplifies waves reflected and transmitted with negative angles, provided the incident wave has a positive angle of incidence.

  4. MR arthrography of the shoulder: Optimizing pulse sequence protocols for the evaluation of cartilage and labrum

    Energy Technology Data Exchange (ETDEWEB)

    Guermazi, Ali, E-mail: Ali.Guermazi@aspetar.com [ASPETAR – Qatar Orthopaedic and Sports Medicine Hospital, Sport City Street, Near Khalifa Stadium, P.O. Box 29222 (Qatar); Department of Radiology, Boston University School of Medicine, 820 Harrison Avenue, FGH Building, 3rd Floor, Boston, MA 02118 (United States); Jomaah, Nabil [ASPETAR – Qatar Orthopaedic and Sports Medicine Hospital, Sport City Street, Near Khalifa Stadium, P.O. Box 29222 (Qatar); Hayashi, Daichi [ASPETAR – Qatar Orthopaedic and Sports Medicine Hospital, Sport City Street, Near Khalifa Stadium, P.O. Box 29222 (Qatar); Department of Radiology, Boston University School of Medicine, 820 Harrison Avenue, FGH Building, 3rd Floor, Boston, MA 02118 (United States); Department of Radiology, Bridgeport Hospital, Yale University School of Medicine, 267 Grant Street, Bridgeport, CT 06610 (United States); Jarraya, Mohamed [ASPETAR – Qatar Orthopaedic and Sports Medicine Hospital, Sport City Street, Near Khalifa Stadium, P.O. Box 29222 (Qatar); Department of Radiology, Boston University School of Medicine, 820 Harrison Avenue, FGH Building, 3rd Floor, Boston, MA 02118 (United States); Silva, Jose Roberto [Department of Radiology, Boston University School of Medicine, 820 Harrison Avenue, FGH Building, 3rd Floor, Boston, MA 02118 (United States); Niu, Jingbo [Clinical Epidemiology Research and Training Unit, Boston University School of Medicine, 650 Albany Street, Suite 200, Boston, MA 02118 (United States); Almusa, Emad; Landreau, Philippe [ASPETAR – Qatar Orthopaedic and Sports Medicine Hospital, Sport City Street, Near Khalifa Stadium, P.O. Box 29222 (Qatar); and others

    2014-08-15

    Objectives: To compare axial T1weighted fat-saturated (T1w fs) and T1w non-fs sequences, and coronal T1w-fs and T2w-fs sequences, for evaluation of cartilage and labrum using CT arthrography (CTA) as the reference. Methods: Patients had MR arthrography (MRA) and CTA of the shoulder on the same day. Cartilage was assessed for superficial and full thickness focal and diffuse damage. Labral lesions were graded for Bankart variants and SLAP lesions. CTA images were read for the same features. The diagnostic performance of MRA including area under the curve (AUC) was evaluated against CTA. Results: When comparing axial sequences, the diagnostic performance for cartilage lesion detection on T1w non-fs was 61.9% (sensitivity) 93.6% (specificity) and 89.5% (accuracy) with AUC 0.782, while that for T1w fs was 61.9%, 94.0%, 89.8% and 0.783. For labral assessment, it was 89.1%, 93.0%, 91.4% and 0.919 for T1w non-fs, and 89.9%, 94.0%, 92.6% and 0.922 for T1w fs. Comparing coronal sequences, diagnostic performance for cartilage was 42.5%, 97.5%, 89.8% and 0.702 for T1w fs, and 38.4%, 98.7%, 90.2%, and 0.686 for T2w fs. For the labrum it was 85.1%, 87.5%, 86.2%, and 0.868 for T1w fs, and 75.7%, 97.5%, 80.8% and 0.816 for T2w fs. Conclusions: Axial T1w fs and T1w non-fs sequences are comparable in their ability to diagnose cartilage and labral lesions. Coronal T1w fs sequence offers slightly higher sensitivity but slightly lower specificity than T2w fs sequence for diagnosis of cartilage and labral lesions.

  5. Indirect MR-arthography in the fellow up of autologous osteochondral transplantation; Indirekte MR-Arthrographie zur Verlaufskontrolle nach autologer osteochondraler Transplantation

    Energy Technology Data Exchange (ETDEWEB)

    Herber, S.; Pitton, M.B.; Kalden, P.; Thelen, M.; Kreitner, K.F. [Mainz Univ. (Germany). Klinik und Poliklinik fuer Radiologie; Runkel, M. [Mainz Univ. (Germany). Klinik und Poliklinik fuer Unfallchirurgie

    2003-02-01

    Purpose: To evaluate the spectrum of findings in indirect MR-arthrography following autologous osteochondral transplantation. Patients and Methods: 10 patients with autogenous osteochondral homografts underwent indirect MR-arthrography at three, 6 and 12 months postoperatively. The MR protocol at 1.5T comprised unenhanced imagings with PD- and T{sub 2}-weighted TSE-sequences with and without fat-suppression as well as T{sub 1}-weighted fat-suppressed SE-sequences before and after iv. contrast administration and after active joint exercise. Image analysis was done by two radiologists in conference and comprised the evaluation of signal intensity (SI) and integrity of the osseous plug and the cartilage surface, as well as the presence of joint effusion or bone marrow edema. Results: At three months, all cases demonstrated a significant bone marrow edema at the recipient and donor site that corresponded to a significant enhancement after iv. contrast administration. The interface between the transplant and the normal bone showed an increased SI at three and 6 months in T{sub 2}-weighted images as well as in indirect MR-arthrography. The marrow signal normalized in most cases after 6 to 12 months, indicating vitality and healing of the transplanted osteochondral graft. The SI of the interface decreased in the same period, demonstrating the stability of the homograft at the recipient site. The osteochondral plugs were well-seated in 9/10 cases. Indirect MR-arthrography was superior to unenhanced imaging in the assessment of the cartilage surface. Cartilage coverage was complete in every case. The transplanted hyaline cartilage as well as the original cartilage showed a significant increase of the SI in indirect MR-arthrography, that did not change in follow up studies. There were no pathological alterations of signal and thickness alterations of the transplanted cartilage in follow up investigations. Conclusion: Indirect MR-arthrography is a useful diagnostic tool

  6. Observation of spin rectification in Pt/yttrium iron garnet bilayer

    Energy Technology Data Exchange (ETDEWEB)

    Rao, Jinwei; Fan, Xiaolong, E-mail: fanxiaolong@lzu.edu.cn; Zhou, Hengan; Zhao, Xiaobing; Zhao, Jing; Zhang, Fengzhen; Xue, Desheng [The Key Lab for Magnetism and Magnetic Materials of Ministry of Education, Lanzhou University, Lanzhou 730000 (China); Ma, Li; Zhou, Shiming [Shanghai Key Laboratory of Special Artificial Microstructure and Technology and Pohl Institute of Solid State Physics and School of Physics Science and Engineering, Tongji University, Shanghai 200092 (China)

    2015-05-07

    We used the ferromagnetic resonance (FMR) to study the dc voltage generation in Pt 20 nm layer deposited on yttrium iron garnet. Although the main contribution to the FMR voltage comes from the inverse spin Hall effect associated with spin pumping, the spin rectification would also contribute the resonance signal via the “new” magnetoresistance effect in Pt layer. Based on a symmetry consideration, we can separate those two effects through angular dependent resonance amplitude.

  7. Use of MR arthrography in detecting tears of the ligamentum teres with arthroscopic correlation

    Energy Technology Data Exchange (ETDEWEB)

    Chang, Connie Y.; Gill, Corey M.; Huang, Ambrose J.; Simeone, Frank J.; Torriani, Martin; Bredella, Miriam A. [Massachusetts General Hospital, Division of Musculoskeletal Imaging and Intervention, Department of Radiology, Boston, MA (United States); McCarthy, Joseph C. [Massachusetts General Hospital, Department of Orthopedics, Boston, MA (United States)

    2014-12-20

    To demonstrate the normal appearance of the ligamentum teres on MR arthrography (MRA) and evaluate the accuracy of MRA in detecting ligamentum teres tears with arthroscopic correlation. Institutional Review Board approval was obtained with a waiver for informed consent because of the retrospective study design. A total of 165 cases in 159 patients (111 females, 48 males; mean age 41 ± 12 years) who underwent both MRA and hip arthroscopy were evaluated for appearance of the ligamentum teres, including the size, number of bundles, and ligamentum teres tears. Marrow edema of the fovea capitis adjacent to the ligamentum teres insertion and the presence of hip plicae were also recorded. The mean thickness and length of the ligamentum teres were 3.5 ± 1.5 mm and 25.2 ± 3.8 mm, respectively. Sensitivity, specificity, positive and negative predictive value, and accuracy of MRA for the detection of ligamentum teres tears were 78, 97, 74, 97, and 95 %, respectively. MRA is an accurate method to evaluate the normal morphology and to detect tears of the ligamentum teres. (orig.)

  8. The diagnostic value of direct CT arthrography using MDCT in the evaluation of acetabular labral tear: with arthroscopic correlation

    Energy Technology Data Exchange (ETDEWEB)

    Ha, Yong-Chan; Kim, Jae Yoon [Chung-Ang University College of Medicine, Department of Orthopaedic Surgery, Seoul (Korea, Republic of); Choi, Jung-Ah; Lee, Guen Young; Kang, Heung Sik [Seoul National University Bundang Hospital, Departments of Radiology, Seoul National University College of Medicine, 166 Gumi-ro, Bundang-gu, Seongnam (Korea, Republic of); Lee, Young-Kyun; Koo, Kyung-Hoi [Seoul National University Bundang Hospital, Orthopaedic Surgery, Seoul National University College of Medicine, Seongnam (Korea, Republic of)

    2013-05-15

    The purpose of this study was first, to determine the sensitivity, specificity, and accuracy of MDCT arthrography (CTA) for the diagnosis of acetabular labral tear and sulcus; second, to correlate tear types using the Lage classification system on CTA compared with the arthroscopic classification; and third, to correlate CTA localization with arthroscopic localization. Direct CTA was performed using 16- or 64-slice MDCT in 126 hips (124 patients) who had chronic groin pain and positive impingement test. Images were reviewed and evaluated by two experienced musculoskeletal radiologists preoperatively. CTA findings were compared with arthroscopic findings in 58 hips (56 patients) under consensus by two orthopedic surgeons. Forty-one of the 58 hips were diagnosed as labral tears on CT arthrography. Forty-three of the 58 hips were shown to have a labral tear on arthroscopy. Sensitivity, specificity, and accuracy for detecting labral tear and sulcus by CTA were 90.7%, 86.7%, and 89.7%, and 93.8%, 97.6% and 96.6% respectively for observer 1, and 90.7% and 80.0%, 87.9% and 87.5%, 95.2%, and 93.1 % respectively for observer 2. Thirty-five out of 41 hips (85%) that were diagnosed with labral tear on CTA correlated substantially with arthroscopic Lage classification (kappa coefficient = 0.65). CTA and arthroscopic findings showed similar distribution patterns of the tears with most lesions located in antero- and postero-superior areas (p = 0.013). Direct CT arthrography using MDCT may be a useful diagnostic technique in the detection of acetabular labral tear. (orig.)

  9. MDCT arthrography of the hip: value of the adaptive statistical iterative reconstruction technique and potential for radiation dose reduction.

    Science.gov (United States)

    Tobalem, Frank; Dugert, Eric; Verdun, Francis R; Dunet, Vincent; Ott, Julien G; Rudiger, Hannes A; Cherix, Stephane; Meuli, Reto; Becce, Fabio

    2014-12-01

    The purpose of this article is to assess the effect of the adaptive statistical iterative reconstruction (ASIR) technique on image quality in hip MDCT arthrography and to evaluate its potential for reducing radiation dose. Thirty-seven patients examined with hip MDCT arthrography were prospectively randomized into three different protocols: one with a regular dose (volume CT dose index [CTDIvol], 38.4 mGy) and two with a reduced dose (CTDIvol, 24.6 or 15.4 mGy). Images were reconstructed using filtered back projection (FBP) and four increasing percentages of ASIR (30%, 50%, 70%, and 90%). Image noise and contrast-to-noise ratio (CNR) were measured. Two musculoskeletal radiologists independently evaluated several anatomic structures and image quality parameters using a 4-point scale. They also jointly assessed acetabular labrum tears and articular cartilage lesions. With decreasing radiation dose level, image noise statistically significantly increased (p=0.0009) and CNR statistically significantly decreased (p=0.001). We also found a statistically significant reduction in noise (p=0.0001) and increase in CNR (p≤0.003) with increasing percentage of ASIR; in addition, we noted statistically significant increases in image quality scores for the labrum and cartilage, subchondral bone, overall diagnostic quality (up to 50% ASIR), and subjective noise (p≤0.04), and statistically significant reductions for the trabecular bone and muscles (p≤0.03). Regardless of the radiation dose level, there were no statistically significant differences in the detection and characterization of labral tears (n=24; p=1) and cartilage lesions (n=40; p≥0.89) depending on the ASIR percentage. The use of up to 50% ASIR in hip MDCT arthrography helps to reduce radiation dose by approximately 35-60%, while maintaining diagnostic image quality comparable to that of a regular-dose protocol using FBP.

  10. PT-symmetric strings

    Energy Technology Data Exchange (ETDEWEB)

    Amore, Paolo, E-mail: paolo.amore@gmail.com [Facultad de Ciencias, CUICBAS, Universidad de Colima, Bernal Díaz del Castillo 340, Colima, Colima (Mexico); Fernández, Francisco M., E-mail: fernande@quimica.unlp.edu.ar [INIFTA (UNLP, CCT La Plata-CONICET), División Química Teórica, Diag. 113 y 64 (S/N), Sucursal 4, Casilla de Correo 16, 1900 La Plata (Argentina); Garcia, Javier [INIFTA (UNLP, CCT La Plata-CONICET), División Química Teórica, Diag. 113 y 64 (S/N), Sucursal 4, Casilla de Correo 16, 1900 La Plata (Argentina); Gutierrez, German [Facultad de Ciencias, CUICBAS, Universidad de Colima, Bernal Díaz del Castillo 340, Colima, Colima (Mexico)

    2014-04-15

    We study both analytically and numerically the spectrum of inhomogeneous strings with PT-symmetric density. We discuss an exactly solvable model of PT-symmetric string which is isospectral to the uniform string; for more general strings, we calculate exactly the sum rules Z(p)≡∑{sub n=1}{sup ∞}1/E{sub n}{sup p}, with p=1,2,… and find explicit expressions which can be used to obtain bounds on the lowest eigenvalue. A detailed numerical calculation is carried out for two non-solvable models depending on a parameter, obtaining precise estimates of the critical values where pair of real eigenvalues become complex. -- Highlights: •PT-symmetric Hamiltonians exhibit real eigenvalues when PT symmetry is unbroken. •We study PT-symmetric strings with complex density. •They exhibit regions of unbroken PT symmetry. •We calculate the critical parameters at the boundaries of those regions. •There are exact real sum rules for some particular complex densities.

  11. Physics counterpart of the PT non-hermitian tight-binding chain

    CERN Document Server

    Jin, L

    2010-01-01

    We explore an alternative way of finding the link between a PT non-Hermitian Hamiltonian and a Hermitian one. Based on the analysis of the scattering problem for an imaginary potential and its time reversal process, it is shown that any real-energy eigenstate of a PT tight-binding lattice with on-site imaginary potentials shares the same wave function with a resonant transmission state of the corresponding Hermitian lattice embedded in a chain. It indicates that the PT eigenstate of a PT non-Hermitian Hamiltonian has connection to the resonance transmission state of the extended Hermitian Hamiltonian.

  12. Inverse spin Hall effect in Pt/(Ga,Mn)As

    Energy Technology Data Exchange (ETDEWEB)

    Nakayama, H. [Laboratory for Nanoelectronics and Spintronics, Research Institute of Electrical Communication, Tohoku University, 2-1-1 Katahira, Aoba-ku, Sendai 980-8577 (Japan); Chen, L. [WPI-Advanced Institute for Materials Research (WPI-AIMR), Tohoku University, 2-1-1 Katahira, Aoba-ku, Sendai 980-8577 (Japan); Chang, H. W. [Laboratory for Nanoelectronics and Spintronics, Research Institute of Electrical Communication, Tohoku University, 2-1-1 Katahira, Aoba-ku, Sendai 980-8577 (Japan); Department of Physics and Center for Nanoscience and Nanotechnology, National Sun Yat-Sen University, Kaohsiung 804, Taiwan (China); Ohno, H.; Matsukura, F., E-mail: f-matsu@wpi-aimr.tohoku.ac.jp [Laboratory for Nanoelectronics and Spintronics, Research Institute of Electrical Communication, Tohoku University, 2-1-1 Katahira, Aoba-ku, Sendai 980-8577 (Japan); WPI-Advanced Institute for Materials Research (WPI-AIMR), Tohoku University, 2-1-1 Katahira, Aoba-ku, Sendai 980-8577 (Japan); Center for Spintronics Integrated Systems, Tohoku University, 2-1-1 Katahira, Aoba-ku, Sendai 980-8577 (Japan)

    2015-06-01

    We investigate dc voltages under ferromagnetic resonance in a Pt/(Ga,Mn)As bilayer structure. A part of the observed dc voltage is shown to originate from the inverse spin Hall effect. The sign of the inverse spin Hall voltage is the same as that in Py/Pt bilayer structure, even though the stacking order of ferromagnetic and nonmagnetic layers is opposite to each other. The spin mixing conductance at the Pt/(Ga,Mn)As interface is determined to be of the order of 10{sup 19 }m{sup −2}, which is about ten times greater than that of (Ga,Mn)As/p-GaAs.

  13. Magnetism of FePt Nanoclusters in Polyimide

    Directory of Open Access Journals (Sweden)

    Mircea Chipara

    2015-01-01

    Full Text Available FePt nanoclusters have been implanted onto polyimide films and subjected to thermal annealing in order to obtain a special magnetic phase (L10 dispersed within the polymer. SQUID measurements quantified the magnetic features of the as-prepared and annealed hybrid films. As-implanted FePt nanoparticles in polyimide films exhibited a blocking temperature of 70 ± 5 K. Thermal annealing in zero and 10 kOe applied magnetic field increased the magnetic anisotropy and coercivity of the samples. Wide Angle X-Ray Scattering confirmed the presence of FePt and L10 phase. All samples (as deposited and annealed exhibited electron spin resonance spectra consisting of two overlapping lines. The broad line was a ferromagnetic resonance originating from FePt nanoparticles. Its angular dependence indicated the magnetic anisotropy of FePt nanoparticles. SEM micrographs suggest a negligible coalescence of FePt nanoparticles, supporting that the enhancement of the magnetic properties is a consequence of the improvement of the L10 structure. The narrow ESR line was assigned to nonmagnetic (paramagnetic impurities within the samples consistent with graphite-like structures generated by the local degradation of the polymer during implantation and annealing. Raman spectroscopy confirmed the formation of graphitic structures in annealed KHN and in KHN-FePt.

  14. Quantitative in vivo CT arthrography of the human osteoarthritic knee to estimate cartilage sulphated glycosaminoglycan content : correlation with ex-vivo reference standards

    NARCIS (Netherlands)

    van Tiel, J; Siebelt, M; Reijman, M; Bos, P.K.; Waarsing, J H; Zuurmond, A-M; Nasserinejad, K; van Osch, G J V M; Verhaar, J A N; Krestin, G P; Weinans, H; Oei, E H G

    OBJECTIVE: Recently, computed tomography arthrography (CTa) was introduced as quantitative imaging biomarker to estimate cartilage sulphated glycosaminoglycan (sGAG) content in human cadaveric knees. Our aim was to assess the correlation between in vivo CTa in human osteoarthritis (OA) knees and ex

  15. Quantitative in vivo CT arthrography of the human osteoarthritic knee to estimate cartilage sulphated glycosaminoglycan content: correlation with ex-vivo reference standards

    NARCIS (Netherlands)

    Tiel, J. van; Siebelt, M.; Reijman, M.; Bos, P.K.; Waarsing, J.H.; Zuurmond, A.M.; Nasserinejad, K.; Osch, G.J.V.M. van; Verhaar, J.A.N.; Krestin, G.P.; Weinans, H.; Oei, E.H.G.

    2016-01-01

    Objective. Recently, computed tomography arthrography (CTa) was introduced as quantitative imaging biomarker to estimate cartilage sulphated glycosaminoglycan (sGAG) content in human cadaveric knees. Our aim was to assess the correlation between in vivo CTa in human osteoarthritis (OA) knees and ex

  16. Inter- and intraobserver variability of MR arthrography in the detection and classification of superior labral anterior posterior (SLAP) lesions: evaluation in 78 cases with arthroscopic correlation

    Energy Technology Data Exchange (ETDEWEB)

    Holzapfel, Konstantin; Waldt, Simone; Bruegel, Melanie; Rummeny, Ernst J.; Woertler, Klaus [Technische Universitaet Muenchen, Department of Radiology, Klinikum rechts der Isar, Munich (Germany); Paul, Jochen; Imhoff, Andreas B. [Technische Universitaet Muenchen, Department of Sports Orthopedics, Klinikum rechts der Isar, Munich (Germany); Heinrich, Petra [Technische Universitaet Muenchen, Institute of Medical Statistics and Epidemiology, Klinikum rechts der Isar, Munich (Germany)

    2010-03-15

    The purpose of this study was to determine inter- and intraobserver variability of MR arthrography of the shoulder in the detection and classification of superior labral anterior posterior (SLAP) lesions. MR arthrograms of 78 patients who underwent MR arthrography before arthroscopy were retrospectively analysed by three blinded readers for the presence and type of SLAP lesions. MR arthrograms were reviewed twice by each reader with a time interval of 4 months between the two readings. Inter- and intraobserver agreement for detection and classification of SLAP lesions were calculated using {kappa} coefficients. Arthroscopy confirmed 48 SLAP lesions: type I (n = 4), type II (n = 37), type III (n = 3), type IV (n = 4). Sensitivity and specificity for detecting SLAP lesions with MR arthrography for each reader were 88.6%/93.3%, 90.9%/80.0% and 86.4%/76.7%. MR arthrographic and arthroscopic grading were concurrent for 72.7%, 68.2% and 70.5% of SLAP lesions for readers 1-3, respectively. Interobserver agreement was excellent ({kappa} = 0.82) for detection and substantial ({kappa} = 0.63) for classification of SLAP lesions. For each reader intraobserver agreement was excellent for detection ({kappa} = 0.93, {kappa} = 0.97, {kappa} = 0.97) and classification ({kappa} = 0.94, {kappa} = 0.84, {kappa} = 0.93) of SLAP lesions. MR arthrography allows reliable and accurate detection of SLAP lesions. In addition, SLAP lesions can be diagnosed and classified with substantial to excellent inter- and intraobserver agreement. (orig.)

  17. PT quantum mechanics.

    Science.gov (United States)

    Bender, Carl M; DeKieviet, Maarten; Klevansky, S P

    2013-04-28

    PT-symmetric quantum mechanics (PTQM) has become a hot area of research and investigation. Since its beginnings in 1998, there have been over 1000 published papers and more than 15 international conferences entirely devoted to this research topic. Originally, PTQM was studied at a highly mathematical level and the techniques of complex variables, asymptotics, differential equations and perturbation theory were used to understand the subtleties associated with the analytic continuation of eigenvalue problems. However, as experiments on PT-symmetric physical systems have been performed, a simple and beautiful physical picture has emerged, and a PT-symmetric system can be understood as one that has a balanced loss and gain. Furthermore, the PT phase transition can now be understood intuitively without resorting to sophisticated mathematics. Research on PTQM is following two different paths: at a fundamental level, physicists are attempting to understand the underlying mathematical structure of these theories with the long-range objective of applying the techniques of PTQM to understanding some of the outstanding problems in physics today, such as the nature of the Higgs particle, the properties of dark matter, the matter-antimatter asymmetry in the universe, neutrino oscillations and the cosmological constant; at an applied level, new kinds of PT-synthetic materials are being developed, and the PT phase transition is being observed in many physical contexts, such as lasers, optical wave guides, microwave cavities, superconducting wires and electronic circuits. The purpose of this Theme Issue is to acquaint the reader with the latest developments in PTQM. The articles in this volume are written in the style of mini-reviews and address diverse areas of the emerging and exciting new area of PT-symmetric quantum mechanics.

  18. Low-field MR arthrography of the shoulder: early results using an open 0.2 T MR system; Niederfeld MR-Arthrographie der Schulter: Erste Ergebnisse mit einem offenen 0,2 T MR-System

    Energy Technology Data Exchange (ETDEWEB)

    Loew, R.; Kreitner, K.F.; Thelen, M. [Mainz Univ. (Germany). Klinik und Poliklinik fuer Radiologie; Runkel, M. [Mainz Univ. (Germany). Klinik und Poliklinik fuer Unfallchirurgie; Zoellner, J. [Mainz Univ. (Germany). Klinik und Poliklinik fuer Orthopaedie

    1998-04-01

    Purpose: To assess the practicability and image quality of doing MR arthrography of the shoulder using a 0.2 T system. Results: Image quality of the T{sub 1}- and T{sub 2}{sup *}-weighted FLASH 2D sequences was regarded as good or adequate and movement artifacts were minor or moderate. STIR sequences were statistically significantly worse in respect of image quality and movement artifacts (p<0.001, p<0.005). The sensitivity and specificity in the diagnosis of rotator cuff rupture as confirmed by surgery was 100% (labrum lesions 100%, 93%). Agreement in the diagnosis of rupture of the supraspinatus and infraspinatus tendons was 0.93 and 0.65. (orig./AJ) [Deutsch] Ziel: Die Durchfuehrbarkeit und die Bildqualitaet einer MR-Arthrographie der Schulter an einem 0,2 Tesla Niederfeldsystem sollten ueberprueft werden. Ergebnisse: Fuer die T{sub 1}-gewichteten und die T{sub 2}{sup *}-gewichteten FLASH-2D-Sequenzen wurde die Bildqualitaet als gut bzw. ausreichend und Bewegungsartefakte als gering oder moderat bewertet. STIR-Sequenzen wurden in bezug auf Bildqualitaet und Bewegungsartefakte statistisch signifikant schlechter beurteilt (p<0,001, p<0,005). Sensitivitaet und Spezifitaet der operierten Patienten in der Beurteilung von Rotatorenmanschettenrupturen betrugen 100% (Labrumlaesionen 100%, 93%). {kappa}-Werte fuer die Uebereinstimmung der Beurteilung von Rupturen der Supraspinatussehne und der Infraspinatussehne betrugen 0,93 und 0,65. (orig./AJ)

  19. Magnetic resonance imaging of the shoulder: a review of potential sources of diagnostic errors

    Energy Technology Data Exchange (ETDEWEB)

    Carroll, K.W. [Radiology Regional Center, Naples, FL (United States); Helms, C.A. [Duke University Medical Center, Department of Radiology, Durham, NC (United States)

    2002-07-01

    Shoulder magnetic resonance (MR) imaging and MR arthrography are frequently utilized in the evaluation of shoulder pain and instability. The clinical scenario and imaging findings may be confusing to clinicians and radiologists and may present diagnostic challenges for those involved in evaluating and treating shoulder pathology. Often rotator cuff and labral abnormalities may be coexistent, clinical manifestations of denervation syndromes may be confusing to clinicians, and normal anatomic variations, imaging pitfalls, and various artifacts may cause dilemmas for the radiologist. This article will review the most frequently encountered mimickers and pitfalls of MR imaging of the shoulder. (orig.)

  20. Diagnostic performance of direct traction MR arthrography of the hip: detection of chondral and labral lesions with arthroscopic comparison

    Energy Technology Data Exchange (ETDEWEB)

    Schmaranzer, Florian; Klauser, Andrea; Henninger, Benjamin [Medical University Innsbruck, Department of Radiology, Innsbruck (Austria); Kogler, Michael; Schmaranzer, Ehrenfried [District Hospital St. Johann in Tyrol, Department of Radiology, St. Johann in Tyrol (Austria); Forstner, Thomas [Johannes Keppler University, Department for Applied Systems Research and Statistics, Linz (Austria); Reichkendler, Markus [District Hospital St. Johann in Tyrol, Department of Orthopedic Surgery, St. Johann in Tyrol (Austria)

    2015-06-01

    To assess diagnostic performance of traction MR arthrography of the hip in detection and grading of chondral and labral lesions with arthroscopic comparison. Seventy-five MR arthrograms obtained ± traction of 73 consecutive patients (mean age, 34.5 years; range, 14-54 years) who underwent arthroscopy were included. Traction technique included weight-adapted traction (15-23 kg), a supporting plate for the contralateral leg, and intra-articular injection of 18-27 ml (local anaesthetic and contrast agent). Patients reported on neuropraxia and on pain. Two blinded readers independently assessed femoroacetabular cartilage and labrum lesions which were correlated with arthroscopy. Interobserver agreement was calculated using κ values. Joint distraction ± traction was evaluated in consensus. No procedure had to be stopped. There were no cases of neuropraxia. Accuracy for detection of labral lesions was 92 %/93 %, 91 %/83 % for acetabular lesions, and 92 %/88 % for femoral cartilage lesions for reader 1/reader 2, respectively. Interobserver agreement was moderate (κ = 0.58) for grading of labrum lesions and substantial (κ = 0.7, κ = 0.68) for grading of acetabular and femoral cartilage lesions. Joint distraction was achieved in 72/75 and 14/75 hips with/without traction, respectively. Traction MR arthrography safely enabled accurate detection and grading of labral and chondral lesions. (orig.)

  1. Humeral avulsion of the anterior shoulder stabilizing structures after anterior shoulder dislocation: demonstration by MRI and MR arthrography

    Energy Technology Data Exchange (ETDEWEB)

    Tirman, P.F.J. [San Francisco Magnetic Resonance Center, San Francisco, CA (United States); Steinbach, L.S. [Department of Radiology, University of California, San Francisco, CA (United States); Feller, J.F. [Department of Veterans Affairs, David Grant USAF Medical Center, Travis Air Force Base, CA (United States); Stauffer, A.E. [Radiologic Imaging Associates, Mission Viejo, CA (United States)

    1996-11-01

    Objective. To demonstrate the MRI findings of an anterior shoulder capsular avulsion from the humerus, with or without subscapularis rupture, after anterior dislocation or severe abduction external rotation injury. Design and patients. We retrospectively reviewed the MRI and MR arthrographic examinations of seven patients who were identified at surgery with avulsion of the anterior shoulder stabilizers from the humerus. MRI was correlated with clinical history and surgical results. Results. MRI findings included: inhomogeneity or frank disruption of the anterior capsule at the humeral insertion (all), fluid intensity anterior to the shoulder (six patients), tear of the subscapularis tendon (six patients), dislocation of the biceps tendon (four patients), and a Hill-Sachs deformity (four patients). MR arthrography additionally found extravasation of contrast through the capsular defect (two patients). Conclusions. Our findings suggest that MRI is helpful for diagnosing humeral avulsion of the anterior glenohumeral capsule, especially when a tear of the subscapularis tendon insertion is present. MR arthrography may be of benefit for diagnosing capsular avulsion without associated subscapularis tendon abnormality. (orig.). With 4 figs.

  2. 16-slice MDCT arthrography of the shoulder: accuracy for detection of glenoid labral and rotator cuff tears

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Gang Deuk; Kim, Huoung Jun; Kim, Hye Won; Oh, Jung Taek; Juhng, Seon Kwan [Wonkwang University Hospital, Iksan (Korea, Republic of); Lee, Sung Ah [Seoul Medical Center, Seoul (Korea, Republic of)

    2007-04-15

    We wanted to determine the diagnostic accuracy of 16-slice MDCT arthrography (CTA) for glenoid labral and rotator cuff tears of the shoulder. We enrolled forty-five patients who underwent arthroscopy after CTA for pain or instability of the shoulder joint. The CTA images were analyzed for the existence, sites and types of glenoid labral tears and the presence and severity of rotator cuff tears. We determined the sensitivity, specificity and accuracy of CTA for detecting glenoid labral and rotator cuff tears on the basis of the arthroscopy findings. At arthroscopy, there were 33 SLAP lesions (9 type I, 23 type II and 1 type III), 6 Bankart lesions and 31 rotator cuff lesions (21 supraspinatus, 9 infraspinatus and 1 subscapularis). On CTA, the sensitivity, specificity and accuracy for detecting 24 SLAP lesions, excluding the type I lesions, were 83%, 100% and 91%, the total rotator cuff tears were 90%, 100% and 98%, the full thickness supraspinatus tendon tears were 100%, 94% and 96%, and the partial thickness supraspinatus tendon tears were 29%, 100% and 89%, respectively. 16-slice MDCT arthrography has high accuracy for the diagnosis of abnormality of the glenoid labrum or rotator cuff tears and it can be a useful alternative to MRI or US.

  3. Ankle post-traumatic osteoarthritis: a CT arthrography study in patients with bi- and trimalleolar fractures

    Energy Technology Data Exchange (ETDEWEB)

    Kraniotis, Pantelis; Petsas, Theodore [University Hospital of Patras, Department of Radiology, Rion, Patras (Greece); Maragkos, Spyridon; Tyllianakis, Minos [University Hospital of Patras, Department of Orthopedics, Rion, Patras (Greece); Karantanas, Apostolos H. [University Hospital, Heraklion, Department of Medical Imaging, Stavrakia, Crete (Greece)

    2012-07-15

    To detect radiographically occult cartilage lesions using CT arthrography (CTa) in patients with malleolar fractures treated with open reduction internal fixation and to correlate the lesions with the functional outcome score. Twenty-one patients (13 men and 8 women, mean age 35 years, range 16-55) underwent ankle CTa after a mean postoperative period of 565 days (range 271-756). CTa images were analyzed by two radiologists. Articular surface post-traumatic collapse and subsequent cartilage defects or erosions were recorded in millimeters and in a binary mode (i.e., present if >50% of cartilage thickness) respectively. The functional outcome was assessed using the American Orthopedic Foot and Ankle Society (AOFAS) score by two orthopaedic surgeons. The statistical analysis correlated the AOFAS score with both imaging parameters and was performed with ANOVA using the MedCalc statistical package, version 11.3. Of the total of 12 articular surface steps recorded, 2/12 (16.67%) were anterolateral, 4/12 (33.33%) posterolateral, 5/12 (41.67%) anteromedial, and 1/12(8.33%) posteromedial. Of the total of 42 cartilage lesions, 7/42 (16.67%) were anterolateral, 14/42 (33.33%) posterolateral, 12/42 (28.57%) anteromedial, and 9/42 (21.43%) posteromedial. The mean AOFAS score was 8.67 (range 5.95-9.70). There was no statistically significant correlation between the AOFAS score and the post-traumatic internal derangement of the ankle joint (p = 0.524). CTa detects radiographically silent cartilage lesions in patients with fractures of the ankle joint. There is no correlation of the extent of lesions and the patient's AOFAS score. (orig.)

  4. Multidetector computed tomography arthrography of the knee: Diagnostic accuracy and indications

    Energy Technology Data Exchange (ETDEWEB)

    De Filippo, Massimo [Department of Clinical Sciences, Section of Radiological Sciences, University of Parma, Parma Hospital, Via Gramsci 14, 43100 Parma (Italy)], E-mail: massimo.defilippo@unipr.it; Bertellini, Annalisa [Department of Clinical Sciences, Section of Radiological Sciences, University of Parma, Parma Hospital, Via Gramsci 14, 43100 Parma (Italy); Pogliacomi, Francesco [Department of Surgery, University of Parma, Parma Hospital, Via Gramsci 14, 43100 Parma (Italy); Sverzellati, Nicola [Department of Clinical Sciences, Section of Radiological Sciences, University of Parma, Parma Hospital, Via Gramsci 14, 43100 Parma (Italy); Corradi, Domenico [Department of Anatomy, University of Parma, Parma Hospital, Via Gramsci 14, 43100 Parma (Italy); Garlaschi, Giacomo [Department of Radiology, University of Genoa, Genoa Hospital, Via Balbi, 5-16126 Genova (Italy); Zompatori, Maurizio [Department of Clinical Sciences, Section of Radiological Sciences, University of Parma, Parma Hospital, Via Gramsci 14, 43100 Parma (Italy)

    2009-05-15

    Purpose: To evaluate the diagnostic accuracy and indications of arthrography with multidetector computed tomography (arthro-MDCT) of the knee, in patients with absolute or relative contraindications to MRI and in patients with periarticular metal implants using diagnostic arthroscopy as the gold standard. Materials and methods: After intra-articular injection of iodixanol and volumetric acquisition, 68 knees in patients of both sexes (30 females, 38 males, age range 32-60 years) were examined with a 16-detector-row CT scanner. The patients had arthralgia but no radiologically detected fractures. They could not be studied by MRI either because of absolute contraindications (subcutaneous electronic implants), surgical metal implants or claustrophobia. In 37 of 68 patients who had had previous knee surgery, the arthro-CT examination was preceded by an MRI on the same day. All examinations were interpreted by two experienced musculoskeletal radiologists. The findings were compared with arthroscopic findings carried out within 28 days of the CT study. Results: In non-operated patients the comparison between arthro-MDCT and arthroscopy showed sensitivity and specificity ranging between 86% and 100%. In the 37 operated knees, arthro-MDCT had an accuracy of 95% compared with 53% of the MRI. Inter-observer agreement was almost perfect (K = 0.97) in the evaluation of all types lesions, both on MDCT and MRI. When arthro-MDCT was compared with MRI in post-operative patients by a McNemar test, a significant difference (p < 0.05) was found between these two techniques. Conclusions: Arthro-MDCT of the knee is a safe technique that provides accurate diagnosis in identifying chondral, fibrocartilaginous and intra-articular ligamentous lesions, in patients that cannot be evaluated by MRI, and in patients after surgical.

  5. Synovial plicae of the hip: evaluation using MR arthrography in patients with hip pain

    Energy Technology Data Exchange (ETDEWEB)

    Bencardino, Jenny T.; La Rocca Vieira, Renata [NYU Hospital for Joint Diseases, Department of Radiology, New York, NY (United States); Kassarjian, Ara [Corades, S.L., Majadahonda-Madrid (Spain); Schwartz, Richard [Longwood MRI Specialists, Brookline, MA (United States); Mellado, Jose M. [Hospital Reina Sofia, Department of Radiology, Tudela (Spain); Kocher, Mininder [Children' s Hospital of Boston, Department of Orthopedic Surgery, Boston, MA (United States)

    2011-04-15

    The appearance and distribution of the intra-articular plicae of the hip have been addressed in few reports in the anatomic and radiological literature. This study aims to determine the prevalence of visible synovial hip plicae using MR arthrography and to measure the association of visible synovial hip plicae with MR arthrographic diagnosis of labral tears, femoroacetabular impingement, and osteoarthritis. Following institutional review board approval, 63 direct MR arthrographic examinations of the hip in 61 patients with a clinical history of hip pain were retrospectively reviewed by two experienced musculoskeletal radiologists in consensus. The following variables were measured using a binary system (0 = absent; 1 = present): labral plica, neck plica, ligamental plica, labral tear, femoroacetabular impingement, and osteoarthritis. The surgical reports and arthroscopic images of 10 patients were reviewed. Statistical analysis was performed using the Fisher's exact test. In all 63 cases at least one plica was visualized on MR-arthrographic images. Labral, neck, and ligamental plicae were found with a prevalence of 76, 97, and 78%, respectively. There was no statistically significant association between the presence of labral tears, femoroacetabular impingement, and osteoarthritis among patients with visible labral, neck, and ligamental plicae. The prevalence of labral tears, femoroacetabular impingement, and osteoarthritis in our patient population was 79, 28, and 28%, respectively. The presence of intra-articular plicae was the only MR-arthrographic finding in 5 of our 63 symptomatic cases. Visible labral, neck, and/or ligamental plicae are highly prevalent on MR-arthrographic images of the hip performed in the setting of hip pain. There was no statistically significant association between the presence of labral tears, femoroacetabular impingement, and osteoarthritis and visible labral, neck, and ligamental plicae. (orig.)

  6. Long head of the biceps brachii tendon: unenhanced MRI versus direct MR arthrography

    Energy Technology Data Exchange (ETDEWEB)

    Tadros, Anthony S.; Huang, Brady K. [University of California, Department of Radiology, San Diego, CA (United States); Wymore, Lucas; Hoenecke, Heinz; Fronek, Jan [Scripps Clinic, Department of Orthopedic Surgery, La Jolla, CA (United States); Chang, Eric Y. [VA San Diego Healthcare System, Radiology Service, San Diego, CA (United States); University of California, Department of Radiology, San Diego, CA (United States)

    2015-09-15

    We sought to determine the diagnostic accuracy of unenhanced MRI and direct MR arthrography (MRA) for evaluation of the intra-articular long head of the biceps brachii tendon (LHBT) using arthroscopy as the gold standard. A retrospective review of patients who underwent shoulder MRI (n = 132) and MRA (n = 67) within 12 months prior to arthroscopy was performed. MR images were independently reviewed by two blinded musculoskeletal radiologists. Routinely recorded arthroscopic photos/videos were reviewed by an orthopedic surgeon. The LHBT was graded as normal, tendinosis, partial thickness tear less or greater than 50 %, and complete tear. Sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), and accuracy for tendinosis and tear detection were calculated. MRI correctly diagnosed fewer normal LHBTs compared to MRA (39-54 % versus 74-84 %, respectively; p < 0.005). MRI and MRA did not differ significantly in the diagnosis of tendinosis (18-36 % and 15-38 %, respectively; p > 0.05) and tears (75-83 % and 64-73 %, respectively; p > 0.05). For tendinosis, MRI versus MRA showed 18-36 % and 15-38 % sensitivity, 69-79 % and 83-91 % specificity, 22-28 % and 18-50 % PPV, 74-76 % and 80-86 % NPV, and 61-64 % and 70-81 % accuracy; respectively. For tears, MRI versus MRA showed 75-83 % and 64-73 % sensitivity, 73-75 % and 82-91 % specificity, 66-69 % and 41-62 % PPV, 82-87 % and 92-94 % NPV, and 74-78 % and 79-88 % accuracy; respectively. No significant difference was found between unenhanced MRI and direct MRA for the detection of tendinosis and tears of LHBTs. (orig.)

  7. PT symmetry and supersymmetry

    CERN Document Server

    Znojil, M

    2002-01-01

    A re-formulated, non-Hermitian version of the Witten's supersymmetric quantum mechanics is presented. Its use of pseudo-Hermitian (so called PT symmetric) Hamiltonians is reviewed and illustrated via several forms of an innovated supersymmetric partnership between strongly singular ("spiked") harmonic oscillators.

  8. Pt nanoparticles embedded on reduced graphite oxide with excellent electrocatalytic properties

    Science.gov (United States)

    Saravanan, Gengan; Mohan, Subramanian

    2016-11-01

    Economically viable electrochemical approach has been developed for the synthesis of Pt nanoparticles through electrodeposition technique on the surface of Reduced Graphite Oxide (RGO). Pt nanoparticles embedded Reduced Graphite Oxide on Glassy Carbon Electrode are employed (Pt-rGO/GCE) for electrooxidation of formic acid. Scanning Electron Microscopy (SEM) image and Transmission Electron Microscopy (TEM) image shows that reduced graphite oxide act as an excellent support to anchor the Pt nanoparticles. Cyclic voltammetry results confirmed that Pt-rGO/GCE enhanced current density as many folds than that of bare platinum electrode for electrooxidation of formic acid. X-ray diffraction (XRD) patterns for Pt-graphene composites illustrate that peaks at 69.15 and 23° for Pt (220) and graphene carbon (002) respectively. 13C NMR spectrum of the electrochemically reduced graphite oxide resonance contains only one peak at 133 ppm which retains graphitic sp2 carbon and does not contain any oxygenated carbon and the carbonyl carbons.

  9. Magnetoelectric effect in FeCo/PMN-PT/FeCo trilayers prepared by electroless deposition of FeCo on PMN-PT crystals with various orientations

    Energy Technology Data Exchange (ETDEWEB)

    Shen, H.Q.; Wang, Y.G., E-mail: yingang.wang@nuaa.edu.cn; Xie, D.; Cheng, J.H.

    2014-10-15

    Highlights: • The composites FeCo/PMN-PT/FeCo were prepared by electroless deposition. • The influence of the crystal cut of PMN-PT on ME coupling is discussed. • Optimizing the crystal cut of the piezoelectric substrate, proper resonant frequency and ME effect could be obtained. - Abstract: The magnetoelectric (ME) effect was studied in the FeCo/PMN-PT/FeCo trilayer composites prepared by electroless deposition of the FeCo layers on the single crystal PMN-PT substrates with various crystal cuts. X-ray diffraction reveals that the orientation of PMN-PT substrate has no effect on the growth of FeCo layer. The structures with PMN-PT crystals of various orientations have different acoustic resonance frequencies. FeCo/PMN-PT/FeCo composites with PMN-PT of 〈0 0 1〉{sup L} × 〈01{sup ‾}1〉{sup W} × 〈0 1 1〉{sup T} crystal cut shows superior ME performance, which is due to the highest piezoelectric module of PMN-PT.

  10. Strong Spin Hall effect in PtMn

    Science.gov (United States)

    Ou, Yongxi; Shi, Shengjie; Ralph, Daniel; Buhrman, Robert

    Recent reports indicate that certain metallic antiferromagnets (AFM) can exhibit a significant spin Hall effect. Here we report a large damping-like spin torque efficiency (ξDL) in PtMn/ferromagnet(FM) bilayer structures, determined from both FM-thickness-dependent spin-torque ferromagnetic resonance (ST-FMR), and harmonic response (HR) measurements of layers with perpendicular magnetic anisotropy (PMA). We find that ξDL can vary from 0.15, depending on the thickness of PtMn, the stacking order of the samples, and the choice of the FM material. The field-like spin torque efficiency (ξFL) is also quite variable, 0phase diagram. These results indicate that AFM PtMn has significant potential both for advancing the understanding the physics of the spin Hall effect in Pt alloys, and for enabling new spintronics functionality.

  11. Selective laser extraction of the Pt group metals

    Energy Technology Data Exchange (ETDEWEB)

    Fadeeva, S.; Krynetsky, B.; Prokhorov, A.; Zhidkov, A. [General Physics Institute, Russian Academy of Science, Moscow (Russian Federation)

    1995-11-15

    The interest to the platinum-group metals extraction from solutions, especially industry waste, is stimulated by their extraordinary chemical inert. The traditional chemical methods of the extraction are uneffective. Have been investigated process of the extraction of metal Pt-group from acid solutions. Discussed processes reduction of noble metals by resonance laser action.

  12. Evaluation of articular cartilage thickness of the humeral head and the glenoid fossa by MR arthrography: anatomic correlation in cadavers

    Energy Technology Data Exchange (ETDEWEB)

    Yeh, L.R. [Univ. of California, San Diego, CA (United States). Veterans Affairs Medical Center]|[Kaohsiung Veterans General Hospital (Taiwan, Province of China). Dept. of Radiology]|[National Yang-Ming Univ., Taipei (Taiwan, Province of China). Dept. of Radiology; Kwak, S.; Kim, Y.S.; Chou, D.S.W.; Muhle, C.; Skaf, A.; Trudell, D.; Resnik, D. [Univ. of California, San Diego, CA (United States). Veterans Affairs Medical Center

    1998-09-01

    To evaluate the accuracy of MR arthrography in determining the thickness of articular cartilage of the humeral head and glenoid fossa. Results. The correlation coefficients for MR arthrographic measurement versus anatomic measurement of the cartilage thickness were 0.7324 and 0.8757 for humeral head and glenoid fossa, respectively. With regard to the humeral head, there was a tendency to overestimate regions of thin cartilage and underestimate regions of thick cartilage. This tendency was not found in the assessment of glenoid cartilage. The mean of the absolute value of MR-anatomic differences was similar on the glenoid side (0.27 mm) and the humeral side (0.29 mm). The accuracy of measurement was significantly better on the glenoid side (Fisher`s r-to-Z transformation: Z=5.21, P=0.000001). (orig.)

  13. Spiral CT arthrography of multiplanar reconstruction and virtual arthroscopy technique in diagnosis of knee with internal derangements

    Institute of Scientific and Technical Information of China (English)

    熊传芝; 郝敬明

    2004-01-01

    5Objective:To evaluate the values of spiral CT arthrography with multiplanar reconstruction and virtual arthroscopy technique in diagnosis of internal derangements of the knee. Methods:Ten bovine knees were used for experiment. The menisci, anterior and posterior cruciate ligaments and cartilage of these 10 bovine knees were injured with a hook. Each of the joints was injected with 100 mi air, then soon scanned with a PQ6000 spiral computed tomography scanner. The data obtained was input into the work station, and multiplanar reconstruction technique was used to illustrate lesions in the knees. The results of CT diagnosis were compared to those found by gross inspection of the specimens. Clinically, 10 knees of 9 patients diagnosed as internal derangement were evaluated with the same method after 50-70 ml air was injected into each of the joints. Nine months later, the data of 2 patients were used for CT endoscopy reconstruction. The results were compared with intraoperative findings. Results:Experimentally,the sensitivity and specificity were 88.9% and 93.9% by detection of meniscal abnormalities, 85.7% and 100% by detection of cruciate ligament lesions, and 72.7% and 100% by detection of cartilage damage, respectively. Clinically, the sensitivity and specificity were 90. 0% and 95.0% by detection of meulscal lesion. As to ligament, the figures were 85.7% and 100% respectively. Images of virtual arthroscopy simulated the images of real arthroscopy. Conclnsious:Spiral CT arthrography of multiplanar reconstruction technique offers fime images of internal structures of the knee, with clear border and internal structure. It is an accurate method for detecting meulscal, cruciate and collateral ligament and cartilaginous lesions that cause internal derangement of the knee.Virtual arthroscopy technique is a hopeful method for detecting reasons of derangement of the knee.

  14. Role of the limbus in femoral-head deformation in developmental dislocation of the hip: findings of two-directional hip arthrography.

    OpenAIRE

    Hara S; Akazawa H; Mitani S; Oda K; Inoue H

    2002-01-01

    Two-directional arthrographic findings made during conservative treatment of developmental dislocation of the hip were compared with the femoral-head configurations and radiological results obtained from long-term follow-up examinations in this retrospective study. Sixty hips were followed until at least age 14. Arthrography was carried out according to Terazawa's method. The shape of the superior, anterior, and posterior limbus was evaluated based on a modified Fujii's classification. The fe...

  15. Pt nanoparticles embedded on reduced graphite oxide with excellent electrocatalytic properties

    Energy Technology Data Exchange (ETDEWEB)

    Saravanan, Gengan, E-mail: saravanan3che@gmail.com [Central University of Tamil Nadu, Department of Chemistry, Thiruvarur, 610101 (India); Mohan, Subramanian, E-mail: sanjnamohan@yahoo.com [EMFT Division, CSIR-Central Electrochemical Research Institute, Tamilnadu, Karaikudi 630 006 (India)

    2016-11-15

    Graphical abstract: RGO/Nano Pt: This study explore the electrocatalytic oxidation performance of reduced graphite oxide (RGO) anchored with nano Pt. This graphene composite reveal superior electrooxidation performance that is associated with the flexible RGO matrix and the uniform distribution of Pt particles, which enhances surface area, fast electron transfer, uniform particle size distribution; consequently, the RGO matrix provides more stability to Pt particles during electrooxidation process. Display Omitted - Highlights: • Greener electrochemical method applied to prepare well-dispersed Pt-rGO. • Pt-rGO large surface area excellent charge transfer better catalytic activity. • Low-cost highly efficient carbon-based electrodes for direct formic acid fuel cell. • rGO an excellent support to anchor Pt nanoparticles on its surface. • Pt-rGO distinctly enhanced current density towards formic acid electrooxidation. - Abstract: Economically viable electrochemical approach has been developed for the synthesis of Pt nanoparticles through electrodeposition technique on the surface of Reduced Graphite Oxide (RGO). Pt nanoparticles embedded Reduced Graphite Oxide on Glassy Carbon Electrode are employed (Pt-rGO/GCE) for electrooxidation of formic acid. Scanning Electron Microscopy (SEM) image and Transmission Electron Microscopy (TEM) image shows that reduced graphite oxide act as an excellent support to anchor the Pt nanoparticles. Cyclic voltammetry results confirmed that Pt-rGO/GCE enhanced current density as many folds than that of bare platinum electrode for electrooxidation of formic acid. X-ray diffraction (XRD) patterns for Pt-graphene composites illustrate that peaks at 69.15 and 23° for Pt (220) and graphene carbon (002) respectively. {sup 13}C NMR spectrum of the electrochemically reduced graphite oxide resonance contains only one peak at 133 ppm which retains graphitic sp{sup 2} carbon and does not contain any oxygenated carbon and the carbonyl

  16. A New Promising Technique of 3D Isovoxel Imaging Using 3T MRI in the Wrist: Comparison with 3T MR Arthrography

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Guen Young; Kim, Baek Hyun; Park, Jong Woong [Korea University Ansan Hospital, Korea University College of Medicine, Ansan (Korea, Republic of)

    2011-02-15

    We wanted to evaluate the usefulness of 3D isovoxel MR imaging using 3T MRI in the wrist joint, as compared with 3T MR arthrography. A total of 33 patients underwent both MR arthrography and 3D isovoxel imaging of the wrist joints using 3T MR, including 11 patients with arthroscopic confirmation. 3D isovoxel MR imaging was performed using an intermediateweighted fast spin echo coronal scan with a 0.4-mm slice thickness and the axial images were reconstructed with a 1-mm slice thickness. One radiologist evaluated for the presence of scapholunate or lunotriquetral ligament tear and she determined the grade of the triangular fibrocartilage complex tear and chondromalacia with its location. We compared the two examinations using kappa values. The rates of detecting wrist injury were similar for both exams with substantial to almost perfect inter-examination agreement (kappa value = 0.864 for scapholunate ligament tear, 0.835 for lunotriquetral ligament tear, 0.799 for TFCC tear and 0.940 for chondromalacia). For the eleven cases that underwent arthroscopy, their results of 3D isovoxel MRI were also similar to that of MR arthrography. 3D isovoxel MR imaging is useful for the evaluation of the wrist joint

  17. Injuries of the scapholunate and lunotriquetral ligaments as well as the TFCC in intra-articular distal radius fractures. Prevalence assessed with MDCT arthrography

    Energy Technology Data Exchange (ETDEWEB)

    Klempka, A.; Wagner, M.; Fodor, S.; Schmitt, R. [Cardiovascular Center Bad Neustadt an der Saale, Department of Diagnostic and Interventional Radiology, Bad Neustadt an der Saale (Germany); Prommersberger, K.J. [Clinic for Hand Surgery, Bad Neustadt an der Saale (Germany); Uder, M. [Friedrich-Alexander-University Erlangen-Nuernberg (FAU), Department of Diagnostic Radiology, Erlangen (Germany)

    2016-03-15

    To evaluate the prevalence of injuries of the scapholunate and lunotriquetral interosseous ligaments (SLIL, LTIL) as well as the triangular fibrocartilage complex (TFCC) in intra-articular distal radius fractures (iaDRF). Two hundred and thirty-three patients with acute iaDRF underwent MDCT arthrography. The SLIL and LTIL were described as normal, partially or completely ruptured. Major injuries of the SLIL were defined as completely ruptured dorsal segments, those of the LTIL as completely ruptured palmar segments. The TFCC was judged as normal or injured. Interobserver variability was calculated. Injury findings were correlated with the types of iaDRF (AO classification). In 159 patients (68.2 %), no SLIL injuries were seen. Minor SLIL injuries were detected in 54 patients (23.2 %), major injuries in 20 patients (8.6 %). No correlation was found between the presence of SLIL lesions and the types of iaDRF. Minor LTIL injuries were seen in 23 patients (9.9 %), major injuries in only 5 patients (2.2 %). The TFCC was altered in 141 patients (60.5 %). Interobserver variability was high for MDCT arthrography in assessing SLIL and TFC lesions, and fair for LTIL lesions. In iaDRF, prevalence of major injuries of the most relevant SLIL is about 9 % as evaluated with CT arthrography. (orig.)

  18. Gamma Radiolytic Formation of Alloyed Ag-Pt Nanocolloids

    Directory of Open Access Journals (Sweden)

    M. K. Temgire

    2011-01-01

    Full Text Available Colloidal dispersions of Ag-Pt composite nanoparticles were prepared by gamma radiolysis technique in the presence of nonionic surfactant Brij'97. Simultaneous as well as sequential reduction methods were employed in order to study the structural formation of Ag-Pt bimetallic clusters. Similar shape and trend was observed in optical spectra for both methods. Radiolysis yielded nearly spherical Ag-Pt bimetallic clusters by use of AgNO3 instead of AgClO4. The disappearance of the silver resonance and the simultaneous growth of the 260 nm resonance are independent of cluster structure and degree of alloying. To understand formation of Ag-Pt aggregate, the optical studies were also done as a function of amount of dose absorbed, concentration of surfactant, that is, Brij'97. The shape of the absorption spectrum did not change with increase in gamma radiation dose. TEM analysis exhibited fine dispersions of Ag-Pt clusters surrounded by a mantle when capped with Brij'97. The particle size obtained was in the range of 5–9 nm. On the basis of optical, XRD, and TEM analysis, alloy formation is discussed.

  19. High-resolution electron microscopy in spin pumping NiFe/Pt interfaces

    Energy Technology Data Exchange (ETDEWEB)

    Ley Domínguez, D., E-mail: david.ley@cimav.edu.mx; Sáenz-Hernández, R. J.; Faudoa Arzate, A.; Arteaga Duran, A. I.; Ornelas Gutiérrez, C. E.; Solís Canto, O.; Botello-Zubiate, M. E.; Rivera-Gómez, F. J.; Matutes-Aquino, J. A. [Centro de Investigación en Materiales Avanzados, S.C., Miguel de Cervantes 120, Complejo Industrial Chihuahua, Chihuahua 31109 (Mexico); Azevedo, A.; Silva, G. L. da; Rezende, S. M. [Departamento de Física, Universidade Federal de Pernambuco, 50670-901 Recife, PE (Brazil)

    2015-05-07

    In order to understand the effect of the interface on the spin pumping and magnetic proximity effects, high resolution transmission electron microscopy and ferromagnetic resonance (FMR) were used to analyze Py/Pt bilayer and Pt/Py/Pt trilayer systems. The samples were deposited by dc magnetron sputtering at room temperature on Si (001) substrates. The Py layer thickness was fixed at 12 nm in all the samples and the Pt thickness was varied in a range of 0–23 nm. A diffusion zone of approximately 8 nm was found in the Py/Pt interfaces and confirmed by energy dispersive X-ray microanalysis. The FMR measurements show an increase in the linewidth and a shift in the ferromagnetic resonance field, which reach saturation.

  20. Characterization of azo dyes on Pt and Pt/polyaniline/dispersed Pt electrodes

    Energy Technology Data Exchange (ETDEWEB)

    Molina, J.; Fernandez, J.; Rio, A.I. del; Bonastre, J. [Departamento de Ingenieria Textil y Papelera, EPS de Alcoy, Universitat Politecnica de Valencia, Plaza Ferrandiz y Carbonell s/n, 03801 Alcoy (Spain); Cases, F., E-mail: fjcases@txp.upv.es [Departamento de Ingenieria Textil y Papelera, EPS de Alcoy, Universitat Politecnica de Valencia, Plaza Ferrandiz y Carbonell s/n, 03801 Alcoy (Spain)

    2012-06-15

    The electrochemical characterization of two organic dyes (amaranth and procion orange MX-2R) has been performed on Pt electrodes and Pt electrodes coated with polyaniline and dispersed Pt. Electrodes with different Pt loads have been synthesized and characterized obtaining that a load of 300 {mu}g cm{sup -2} was the optimum one. Scanning electron microscopy (SEM) and atomic force microscopy (AFM) was employed to observe the distribution and morphology of the Pt nanoparticles. The electroactivity of the electrodes has also been characterized by means of scanning electrochemical microscopy (SECM). The chemical characterization of Pt dispersed Pani coated Pt electrodes (Pt-Pani-Pt) was performed by means of X-ray photoelectron spectroscopy (XPS). The electrochemical characterization of the dyes has been performed by means of cyclic voltammetry. Voltammograms have shown that the presence of the dyes diminishes characteristic Pt oxidation and reduction peaks. However, redox processes due to the dyes, appeared in the voltammograms. The different species responsible of these redox processes were generated in the vicinity of the electrode and were not adsorbed on the electrode surface since after stirring, the different redox processes disappeared. Characterization with different scan rates showed that redox processes of both dyes were controlled by diffusion.

  1. Bounded dynamics in finite PT-symmetric magnetic metamaterials.

    Science.gov (United States)

    Molina, Mario I

    2014-03-01

    We examine the PT-symmetry-breaking transition for a magnetic metamaterial of a finite extent, modeled as an array of coupled split-ring resonators in the equivalent circuit model approximation. Small-size arrays are solved completely in closed form, while for arrays larger than N=5 results were computed numerically for several gain and loss spatial distributions. In all cases, it is found that the parameter stability window decreases rapidly with the size of the array, until at N=20 approximately it is not possible to support a stable PT-symmetric phase.

  2. Nonreciprocal Scattering by PT-symmetric stack of the layers

    CERN Document Server

    Shramkova, Oksana

    2015-01-01

    The nonreciprocal wave propagation in PT-symmetric periodic stack of binary dielectric layers characterised by balances loss and gain is analysed. The main mechanisms and resonant properties of the scattered plane waves are illustrated by the simulation results, and the effects of the periodicity and individual layer parameters on the stack nonreciprocal response are discussed. Gaussian beam dynamics in this type of structure is examined. The beam splitting in PT-symmetric periodic structure is observed. It is demonstrated that for slant beam incidence the break of the symmetry of field distribution takes place.

  3. PT-symmetric quantum oscillator in an optical cavity

    CERN Document Server

    Longhi, Stefano

    2016-01-01

    The quantum harmonic oscillator with parity-time ($\\mathcal{PT}$) symmetry, obtained from the ordinary (Hermitian) quantum harmonic oscillator by an imaginary displacement of the spatial coordinate, provides an important and exactly-solvable model to investigate non-Hermitian extension of the Ehrenfest theorem. Here it is shown that transverse light dynamics in an optical resonator with off-axis longitudinal pumping can emulate a $\\mathcal{PT}$-symmetric quantum harmonic oscillator, providing an experimentally accessible system to investigate non-Hermitian coherent state propagation.

  4. Comparison between conventional MR arthrograhphy and abduction and external rotation MR arthrography in revealing tears of the antero-inferior glenoid labrum

    Energy Technology Data Exchange (ETDEWEB)

    Choi, Jung Ah; Suh, Sang Il; Kim, Baek Hyun; Cha, Sang Hoon [Korea University Guro Hospital, Seoul (Korea, Republic of); Kim, Myung Gyu; Lee, Ki Yeol [Inje University, Gimhae (Korea, Republic of); Lee, Chang Hee [Konkok University, Seoul (Korea, Republic of)

    2001-12-01

    To compare, in terms of their demonstration of tears of the anterior glenoid labrum, oblique axial MR arthrography obtained with the patient's shoulder in the abduction and external rotation (ABER) position, with conventional axial MR arthrography obtained with the patient's arm in the neutral position. MR arthrography of the shoulder, including additional oblique axial sequences with the patient in the ABER position, was performed in 30 patients with a clinical history of recurrent anterior shoulder dislocation. The degree of anterior glenoid labral tear or defect was evaluated in both the conventional axial and the ABER position by two radiologists. Decisions were reached by consensus, and a three-point scale was used: grade 1=normal; grade 2=probable tear, diagnosed when subtle increased signal intensity in the labrum was apparent; grade 3=definite tear/defect, when a contrast material-filled gap between the labrum and the glenoid rim or deficient labrum was present. The scores for each imaging sequence were averaged and to compare conventional axial and ABER position scans, Student's t test was performed. In 21 (70%) of 30 patients, the same degree of anterior instability was revealed by both imaging sequences. Eight (27%) had a lower grade in the axial position than in the ABER position, while one (3%) had a higher grade in the axial position. Three whose axial scan was grade 1 showed only equivocal evidence of tearing, but their ABER-position scan, in which a contrast material-filled gap between the labrum and the glenoid rim was present, was grade 3. The average grade was 2.5 (SD=0.73) for axial scans and 2.8 (SD=0.46) for the ABER position. The difference between axial and ABER-position scans was statistically significant (p<0.05). MR arthrography with the patient's shoulder in the ABER position is more efficient than conventional axial scanning in revealing the degree of tear or defect of the anterior glenoid labrum. When equivocal

  5. Microscopic evidence of strain-mediated magnetoelectric coupling in Co/Pt multilayers/PMN-PT(011) heterostructures

    Science.gov (United States)

    Sun, Ying; Wang, Wenbo; Wu, Weida; Zheng, Xiaoli; Cai, Jianwang; Zhao, Yonggang; Liu, Ming

    A promising way to control magnetization(M) via an electric field(E-field) is using magnetoelectric(ME) effect in FM/FE heterostructures. We use magnetic(electric) force microscopy(M(e)FM) to study the strain-mediated E-field modulation of M in (Co/Pt)n with perpendicular magnetic anisotropy(PMA) or in-plane anisotropy on PMN-PT(011) substrates. MFM were performed on (Co/Pt)n with an DC E-field applied to PMN-PT. In MeFM, we superimpose an AC modulation on a DC one and utilize lock-in technique to detect weak ME effect. For (Co/Pt)n with PMA, MFM images show stripe domains with no obvious changes at varied DC E-fields. However, MeFM shows interesting structures and the image contrast reverses sign at opposite strain slopes of the PMN-PT substrate. For sample with in-plane anisotropy, both MFM and MeFM images show dipole-like domains. Interestingly, the MeFM image contrast reverses sign at opposite strain slopes of the substrate. The sign reversal of MeFM contrast indicates that features revealed by MeFM are intrinsic local ME effect. Our MeFM data are consistent with the ferromagnetic resonance results showing that strain-induced anisotropy change will cause part of M switching to the in-plane direction. Possible scenarios will be discussed.

  6. NQRS Data for Ga5PtU (Subst. No. 2235)

    Science.gov (United States)

    Chihara, H.; Nakamura, N.

    This document is part of Subvolume B 'Substances Containing C10H16 … Zn' of Volume 48 'Nuclear Quadrupole Resonance Spectroscopy Data' of Landolt-Börnstein - Group III 'Condensed Matter'. It contains an extract of Section '3.2 Data tables' of the Chapter '3 Nuclear quadrupole resonance data' providing the NQRS data for Ga5PtU (Subst. No. 2235)

  7. Analysis of the excitation profiles of Raman bands of linear-chain mixed-valence complexes. The geometry of [Pt(en) 2][Pt(en) 2Br 2]Br 4 in the intervalence state

    Science.gov (United States)

    Clark, Robin J. H.; Dines, Trevor J.

    1991-10-01

    Calculations of the resonance Raman excitation profiles for the ν 1 band and its overtones have been performed for the linear- chain mixed-valence platinum complex [Pt(en) 2Br 2]Br 4. It is found that the Pt IV length increases by 0.075 Å in the intervalence state. A satisfactory fit to the excitation profiles requires the inclusion of a second excited state at 16500 cm -1, which we have assigned to Br→Pt IV charge transfer.

  8. Detection of rotator cuff lesions with indirect MR angiography; Indirekte MR-Arthrographie in der Diagnostik von Rotatorenmanschettenlaesionen

    Energy Technology Data Exchange (ETDEWEB)

    Rudolph, J.; Lorenz, M.; Schroeder, R.; Felix, R. [Humboldt-Universitaet, Berlin (Germany). Klinik fuer Strahlenheilkunde; Suedkamp, N.P. [Humboldt-Universitaet, Berlin (Germany). Klinik fuer Unfall- und Wiederherstellungschirurgie; Maeurer, J. [Radiologie am Prinzregentenplatz, Muenchen (Germany)

    2000-08-01

    Purpose: To determine the value of indirect MR arthrography in lesions of the rotator cuff, prospectively versus arthroscopy. Methods: 63 patients with suspected shoulder pathology were examined: Oblique-coronary and axial T{sub 1}w sequences, axial FLASH-2 D sequences, furthermore oblique-coronary T{sub 2}- and PD-weighted sequences were taken. After intravenous administration of 0.1 mmol Gd-DTPA/kilogram body weight and active motion of the shoulder T{sub 1}w sequences were repeated. Signal intensities (SI) inside the tendon were quantitatively measured by the ROI technique (region-of-interest) and the percentual contrast-enhancement CE was calculated. In 32 patients the results were confirmed by surgical follow-up. Results: The mean SI measured in the supraspinous tendon were higher in lesions (degeneration, impingement, partial and total rupture), before as well as after contrast medium, compared to intact findings (p<0.05). Similarly the percentual CE (p<0.05) was higher. We detected 9 total ruptures and three impingements (for both sensitivity before/after Gd-DTPA 100%), furthermore 6 partial ruptures. Of the latter three were false positive and one false negative, leading to sensitivity of 75% and a specificity of 50%. Conclusion: The visualization of rotator cuff lesions can be optimized with indirect MR arthrography. The detection of partial ruptures remains faulty, because the exact demarcation of degenerative change and partial rupture is still difficult. (orig.) [German] Ziel: Untersuchung der Wertigkeit der indirekten MR-Arthrograhie bei Laesionen der Rotatorenmanschette (RM) im Rahmen einer prospektiven Studie vs. Arthroskopie. Methoden: 63 Patienten mit Verdacht auf Schulterlaesionen wurden untersucht: T{sub 1}-Sequenzen nativ obliquekoronar und axial, FLASH-2-D-Sequenzen axial sowie T{sub 2}- und PD-gewichtete Sequenzen oblique-koronar. Nach intravenoeser Gabe von 0,1 mmol Gd-DTPA/kg Koerpergewicht aktive Bewegung der Schulter und wiederum T{sub 1

  9. Zero index metamaterials with PT symmetry in a waveguide system.

    Science.gov (United States)

    Fu, Yangyang; Xu, Yadong; Chen, Huanyang

    2016-01-25

    Inspired by the concept of parity-time symmetry, we propose a new waveguide system consisting of zero index metamaterials with an air gap. Based on analytical calculations and numerical simulations, we demonstrate that there are two exceptional points in such a system, which can induce unidirectional transparency. However, the introduced air gap could effectively manipulate the property of the waveguide system with PT symmetry. In particular, coherent perfect absorber-laser modes could be excited in PT broken phase, if a specific phase difference in the air gap is obtained. More interestingly, when Fabry-Pérot resonances take place in the air gap, the PT symmetry property will be suppressed, i.e., the value of loss/gain could not affect transmission and reflection of the waveguide. As a result, perfect bidirectional transmission without reflection can occur in the waveguide system.

  10. PtSi Clustering in Silicon Probed by Transport Spectroscopy

    Directory of Open Access Journals (Sweden)

    Massimo Mongillo

    2013-12-01

    Full Text Available Metal silicides formed by means of thermal annealing processes are employed as contact materials in microelectronics. Control of the structure of silicide/silicon interfaces becomes a critical issue when the characteristic size of the device is reduced below a few tens of nanometers. Here, we report on silicide clustering occurring within the channel of PtSi/Si/PtSi Schottky-barrier transistors. This phenomenon is investigated through atomistic simulations and low-temperature resonant-tunneling spectroscopy. Our results provide evidence for the segregation of a PtSi cluster with a diameter of a few nanometers from the silicide contact. The cluster acts as a metallic quantum dot giving rise to distinct signatures of quantum transport through its discrete energy states.

  11. Coexistence of multiple charge-density waves and superconductivity in SrPt2As2 revealed by 75As-NMR /NQR and 195Pt-NMR

    Science.gov (United States)

    Kawasaki, Shinji; Tani, Yoshihiko; Mabuchi, Tomosuke; Kudo, Kazutaka; Nishikubo, Yoshihiro; Mitsuoka, Daisuke; Nohara, Minoru; Zheng, Guo-qing

    2015-02-01

    The relationship between charge-density wave (CDW) orders and superconductivity in arsenide superconductor SrPt2As2 with Tc=5.2 K which crystallizes in the CaBe2Ge2 -type structure was studied by 75As nuclear magnetic resonance (NMR) measurements up to 520 K, and 75As nuclear quadrupole resonance (NQR) and 195Pt-NMR measurements down to 1.5 K. At high temperature, 75As-NMR spectrum and nuclear-spin-relaxation rate (1 /T1) have revealed two distinct CDW orders, one realized in the As-Pt-As layer below TCDWAs (1 )=410 K and the other in the Pt-As-Pt layer below TCDWAs (2 )=255 K . The 1 /T1 measured by 75As-NQR shows a clear Hebel-Slichter peak just below Tc and decreases exponentially well below Tc. Concomitantly, 195Pt Knight shift decreases below Tc. Our results indicate that superconductivity in SrPt2As2 is in the spin-singlet state with an s -wave gap and is robust under the two distinct CDW orders in different layers.

  12. Development of SMD 32.768 kHz tuning fork-type crystals using photolithography and selective etching process. Pt. I. Selective etching of an array of quartz tuning fork resonators

    Energy Technology Data Exchange (ETDEWEB)

    Lee, S. [Samsung Electro-Mechanics Co., Ltd., Suwon City (Korea); Kang, K.M. [National Univ. of Technology, Seoul (Korea). Dept. of Materials Engineering

    2001-05-01

    Negative photoresist photolithography was found superior to previously used positive photoresist photolithography to etch array of quartz tuning forks for use in Qualcomm trademark mobile station modem (MSM), 3000{sup TM} central processing unit (CPU), chips of code division multiple access (CDMA), personal communication system (PCS), and global system for mobile communication (GSM) units. Optimum processing condition was devised for reproducible precision etching of Z-cut quartz wafer into array of tuning forks. Tuning fork pattern was transferred via ordinary photolithographical chromium/quartz glass template using a standard single-sided aligner and subsequent negative photoresist development. A tightly adhering and pinhole-free 600/2000 A chromium/gold mask is coated over the developed photoresist pattern which was subsequently stripped in acetone. This procedure was repeated on the backside of the wafer. With protective metallization area of tuning fork geometry thus formed, etching through quartz wafer was done at 80 C in a {+-} 1.5 C controlled bath containing concentrated solution of ammonium bifluoride to remove unwanted area of the quartz wafer. The quality of quartz wafer surface finish after quartz etching depended primarily on the surface finish of quartz wafer prior to etching and the quality of quartz crystals used. At 80 C, selective etching of 100 {mu}m quartz wafer could be effected within 90 min. Reproducible precision selective etching method has thus been established and enables mass production of miniature tuning fork resonators with electrode patterns on them photolithographically. (orig.)

  13. Rotator cuff disorders: How to write a surgically relevant magnetic resonance imaging report?

    Science.gov (United States)

    Tawfik, Ahmed M; El-Morsy, Ahmad; Badran, Mohamed Aboelnour

    2014-06-28

    Evaluation of rotator cuff is a common indication for magnetic resonance imaging (MRI) scanning of the shoulder. Conventional MRI is the most commonly used technique, while magnetic resonance (MR) arthrography is reserved for certain cases. Rotator cuff disorders are thought to be caused by a combination of internal and external mechanisms. A well-structured MRI report should comment on the relevant anatomic structures including the acromial type and orientation, the presence of os acromiale, acromio-clavicular degenerative spurs and fluid in the subacromial subdeltoid bursa. In addition, specific injuries of the rotator cuff tendons and the condition of the long head of biceps should be accurately reported. The size and extent of tendon tears, tendon retraction and fatty degeneration or atrophy of the muscles are all essential components of a surgically relevant MRI report.

  14. Identification of {sup 166}Pt and {sup 167}Pt

    Energy Technology Data Exchange (ETDEWEB)

    Bingham, C.R.; Toth, K.S.; Batchelder, J.C.; Blumenthal, D.J.; Brown, L.T.; Busse, B.C.; Conticchio, L.F.; Davids, C.N.; Davinson, T.; Henderson, D.J.; Irvine, R.J.; Seweryniak, D.; Walters, W.B.; Woods, P.J.; Zimmerman, B.E. [The University of Tennessee, Knoxville, Tennessee 37996 (United States)]|[Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831 (United States)]|[Louisiana State University, Baton Rouge, Louisiana 70803 (United States)]|[Argonne National Laboratory, Argonne, Illinois 60439 (United States)]|[Vanderbilt University, Nashville, Tennessee 37235 (United States)]|[Oregon State University, Corvallis, Oregon 97331 (United States)]|[University of Maryland, College Park, Maryland 20742 (United States)]|[Edinburgh University, Edinburgh, EH9 3JZ (United Kingdom)

    1996-07-01

    In a series of {sup 78}Kr bombardments of {sup 92}Mo the new isotopes {sup 166}Pt and {sup 167}Pt were identified via their {alpha}-decay properties. The {alpha}-decay energies and half-lives of these two nuclides are as follows. (1) {sup 166}Pt, {ital E}{sub {alpha}} = 7110(15) keV, {ital T}{sub 1/2} = 0.3(1) ms, and (2) {sup 167}Pt, {ital E}{sub {alpha}} = 6988(10) keV, {ital T}{sub 1/2} = 0.7(2) ms. Also, the half-life of {sup 168}Pt, which was previously unknown, was determined to be 2.0(4) ms. In a separate but concurrent experiment involving {sup 78}Kr + {sup 96}Ru reactions, {sup 170}Pt was made and a half-life of 14.7(5) ms was measured for it; the one published value is 6{sub {minus}2}{sup +5} ms. Results for {sup 162{minus}164}Os contained in the same data sets were also analyzed and by using mother-daughter correlations, the {alpha} branches of {sup 162,163,164}Os were established to be near 100{percent}. {copyright} {ital 1996 The American Physical Society.}

  15. PT Metamaterials via Complex-Coordinate Transformation Optics

    CERN Document Server

    Castaldi, Giuseppe; Galdi, Vincenzo; Alu', Andrea; Engheta, Nader

    2012-01-01

    We extend the transformation-optics paradigm to a complex spatial coordinate domain, in order to deal with electromagnetic metamaterials characterized by balanced loss and gain, giving special emphasis to parity-time (PT) symmetry metamaterials. We apply this general theory to complex-source-point radiation and unidirectional invisibility, illustrating the capability and potentials of our approach in terms of systematic design, analytical modeling and physical insights into complex-coordinate wave-objects and resonant states.

  16. MR arthrography including abduction and external rotation images in the assessment of atraumatic multidirectional instability of the shoulder

    Energy Technology Data Exchange (ETDEWEB)

    Schaeffeler, Christoph [Technische Universitaet Muenchen, Department of Radiology, Munich (Germany); Kantonsspital Graubuenden, Musculoskeletal Imaging, Chur (Switzerland); Waldt, Simone; Bauer, Jan S.; Rummeny, Ernst J.; Woertler, Klaus [Technische Universitaet Muenchen, Department of Radiology, Munich (Germany); Kirchhoff, Chlodwig [Technische Universitaet Muenchen, Department of Traumatology, Munich (Germany); Haller, Bernhard [Technische Universitaet Muenchen, Institute for Medical Statistics and Epidemiology, Munich (Germany); Schroeder, Michael [Center for Sports Orthopedics and Medicine, Orthosportiv, Munich (Germany); Imhoff, Andreas B. [Technische Universitaet Muenchen, Department of Orthopedic Sports Medicine, Munich (Germany)

    2014-06-15

    To evaluate diagnostic signs and measurements in the assessment of capsular redundancy in atraumatic multidirectional instability (MDI) of the shoulder on MR arthrography (MR-A) including abduction/external rotation (ABER) images. Twenty-one MR-A including ABER position of 20 patients with clinically diagnosed MDI and 17 patients without instability were assessed by three radiologists. On ABER images, presence of a layer of contrast between the humeral head (HH) and the anteroinferior glenohumeral ligament (AIGHL) (crescent sign) and a triangular-shaped space between the HH, AIGHL and glenoid (triangle sign) were evaluated; centring of the HH was measured. Anterosuperior herniation of the rotator interval (RI) capsule and glenoid version were determined on standard imaging planes. The crescent sign had a sensitivity of 57 %/62 %/48 % (observers 1/2/3) and specificity of 100 %/100 %/94 % in the diagnosis of MDI. The triangle sign had a sensitivity of 48 %/57 %/48 % and specificity of 94 %/94 %/100 %. The combination of both signs had a sensitivity of 86 %/90 %/81 % and specificity of 94 %/94 %/94 %. A positive triangle sign was significantly associated with decentring of the HH. Measurements of RI herniation, RI width and glenoid were not significantly different between both groups. Combined assessment of redundancy signs on ABER position MR-A allows for accurate differentiation between patients with atraumatic MDI and patients with clinically stable shoulders; measurements on standard imaging planes appear inappropriate. (orig.)

  17. Cartilage lesions of the glenohumeral joint: diagnostic effectiveness of multidetector spiral CT arthrography and comparison with arthroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Lecouvet, Frederic E.; Dorzee, Benjamin; Berg, Bruno C. vande; Malghem, Jacques [Cliniques Universitaires St Luc, Universite Catholique de Louvain, Department of Radiology, Brussels (Belgium); Dubuc, Jean E. [Cliniques Universitaires St Luc, Universite Catholique de Louvain, Department of Orthopaedic Surgery, Brussels (Belgium); Jamart, Jacques [Mont Godinne University Hospital, Center of Biostatistics, Yvoir (Belgium)

    2007-07-15

    This study assessed the diagnostic effectiveness of multidetector spiral CT arthrography (MDCTa) in detecting hyaline cartilage abnormalities of the shoulder joint, with correlation to arthroscopy. Shoulder MDCTa images prospectively obtained in 22 consecutive patients (mean age, 50 years; age range, 23-74 years; 12 female, 10 male) were evaluated for glenohumeral cartilage lesions. Two musculoskeletal radiologists independently analysed the cartilage surfaces of the humeral head and of the glenoid fossa in nine anatomical surface areas. Observations of MDCTa were compared to arthroscopic findings. The sensitivity and specificity of MDCTa for grade 2 (substance loss <50%) or higher and grade 3 (substance loss {>=}50%) or higher cartilage lesions, the Spearman correlation coefficient between arthrographic and arthroscopic grading, and K statistics for assessing Intra and Interobserver reproducibility were determined. At MDCTa, sensitivities and specificities ranged between 80% and 94% for the detection of grade 2 or higher cartilage lesions, and between 88% and 98% for the detection of grade 3 or higher cartilage lesions. Spearman correlation coefficients between MDCTa and arthroscopic grading of articular surfaces ranged between 0.532 and 0.651. Interobserver agreement was moderate for grading all articular surfaces ({kappa} = 0.457), but substantial to almost perfect for detecting lesions with substance loss ({kappa}, 0.618-0.876). In conclusion, MDCTa is accurate for the study of cartilage surface in the entire shoulder joint. This technique may beneficially impact patient's management by means of selecting the proper treatment approach. (orig.)

  18. A radiological study of the patella and the cartilage of patella by computed tomography following double-contrast arthrography

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Myung Joon; Yang, Seoung Oh [Capital Armed Forces General Hospital, Seoul (Korea, Republic of)

    1987-04-15

    Recurrent subluxation or dislocation of the patella is a painful condition that frequently leads to chondromalacia or arthrosis of the patellofemoral joint. A radiographic evaluation of the patella and patella cartilage is important in the diagnosis of chondromalacia and mal alignment. Authors performed the patellofemoral joint CT following the double contrast arthrography in 53 patients with knee joint pains who had visited to Capital Armed Forces General Hospital from July to December, 1986. Authors analysed the shape and position of patella and the shape of patella cartilage. The results were as follows; 1. shape of patella:The most common types are type II/III (14 cases) and type III (14 cases). type III {yields} IV-9 cases, type I-5 cases, type IV-5 cases, other type-4 cases, type II-2 cases, no type V. 2. position of patella:Only 2 cases showed subluxation and external rotation of patella. 3. shape of patella cartilage:a)congruous cartilage-21 cases (39.6%) b)regular cartilage-22 cases (41.5%) c)irregular cartilage-10 cases (18.9%) irregular imbibition of contrast media-7 cases localized loss of cartilage or erosion-2 cases thinning of cartilage-1 case 4. Fissure and erosions of cartilages in 3 cases were confirmed by operation and knee arthroscopy.

  19. Prevalence of the acetabular sublabral sulcus at MR arthrography in patients under 17 years of age: does it exist?

    Energy Technology Data Exchange (ETDEWEB)

    Magerkurth, Olaf [University of Michigan, Department of Radiology, Ann Arbor, MI (United States); Hospital Baden, Department of Radiology, Baden (Switzerland); Jacobson, Jon A.; Morag, Yoav; Fessell, David [University of Michigan, Department of Radiology, Ann Arbor, MI (United States); Bedi, Asheesh; Sekiya, Jon K. [University of Michigan, Department of Orthopedic Surgery, Ann Arbor, MI (United States)

    2015-04-18

    To retrospectively determine characteristics of contrast-filled acetabular labral clefts in patients under the age of 17 years at MR arthrography (Mra) correlated with arthroscopy, which may impact the thinking regarding the existence of a sublabral sulcus. After IRB approval, 41 patients under the age of 17 who had MRa were identified. The following observations of contrast-filled clefts were assessed: (1) presence/absence, (2) location, (3) depth, (4) abnormal signal within the labrum and (5) shape (linear, gaping, complex). Fisher's exact and the Wilcoxon matched-pairs signed-rank test were performed. Interreader agreement was calculated with Cohen's k. Reader 1 found clefts in 41 %. Depth was less than half in 6 %, more than half in 65 % and full thickness in 29 %. Shape was linear in 53 %, gaping in 18 % and complex in 29 %. Signal changes occurred in 88 %. Reader 2 found clefts in 29 %. Depth was less than half in 17 %, more than half in 58 % and full thickness in 25 %. Shape was linear in 50 %, gaping in 42 % and complex in 17 %. Signal changes occurred in 50 %. None of the clefts fulfilled the criteria for a sublabral sulcus at MRa and arthroscopy. None of the clefts found in our subjects under the age of 17 years met the MRa and arthroscopy criteria for a sublabral sulcus, which supports the theory that such clefts represent labral tears. (orig.)

  20. Supraspinatus tendon tears at 3.0 T shoulder MR arthrography: diagnosis with 3D isotropic turbo spin-echo SPACE sequence versus 2D conventional sequences

    Energy Technology Data Exchange (ETDEWEB)

    Jung, Joon-Yong; Jee, Won-Hee; Park, Michael Y.; Lee, So-Yeon [Seoul St. Mary' s Hospital, The Catholic University of Korea, Department of Radiology, Seoul (Korea, Republic of); Kim, Yang-Soo [Seoul St. Mary' s Hospital, The Catholic University of Korea, Department of Orthopedic Surgery, Seoul (Korea, Republic of)

    2012-11-15

    To assess the diagnostic performance of shoulder MR arthrography with 3D isotropic fat-suppressed (FS) turbo spin-echo sequence (TSE-SPACE) for supraspinatus tendon tears in comparison with 2D conventional sequences at 3.0 T. The study was HIPAA-compliant and approved by the institutional review board with a waiver of informed consent. Eighty-seven arthroscopically confirmed patients who underwent 3.0 T shoulder MR arthrography with 2D sequences and 3D TSE-SPACE were included in a consecutive fashion from March 2009 to February 2010. Two reviewers independently analyzed 2D sequences and 3D TSE-SPACE. Sensitivity, specificity, accuracy, and interobserver agreement ({kappa}) were compared between 2D sequences and 3D TSE-SPACE for full-thickness and partial-thickness supraspinatus tendon tears together and for partial-thickness supraspinatus tendon tears alone. There were 33 full-thickness tears and 28 partial-thickness tears of supraspinatus tendons. For full-thickness and partial-thickness supraspinatus tendon tears together, the mean sensitivity, specificity, and accuracy of both readers were 96, 92, and 94% on 2D sequences and 91, 84, and 89% on 3D TSE-SPACE. For partial-thickness supraspinatus tendon tears alone, the mean sensitivity, specificity, and accuracy were 95, 92, and 94% on 2D sequences and 84, 85, and 84% on 3D TSE-SPACE. There was no statistical difference between 2D sequences and 3D TSE-SPACE. Interobserver agreements were almost perfect on 2D conventional sequences and substantial on 3D TSE-SPACE. Compared with 2D conventional sequences, MR arthrography using 3D TSE-SPACE was comparable for diagnosing supraspinatus tendon tears despite limitations in detecting small partial-thickness tears and in discriminating between full-thickness and deep partial-thickness tears. (orig.)

  1. 3-T direct MR arthrography of the wrist: Value of finger trap distraction to assess intrinsic ligament and triangular fibrocartilage complex tears

    Energy Technology Data Exchange (ETDEWEB)

    Cerny, Milena; Marlois, Romain [Department of Diagnostic and Interventional Radiology, Centre Hospitalier Universitaire Vaudois, University of Lausanne, Rue du Bugnon 46, 1011 Lausanne (Switzerland); Theumann, Nicolas [Institute of Radiology, Clinique Hirslanden Bois-Cerf, Avenue d’Ouchy 31, 1006 Lausanne (Switzerland); Bollmann, Christof; Wehrli, Laurent [Department of Plastic and Hand Surgery, Clinique Longeraie and Centre Hospitalier Universitaire Vaudois, University of Lausanne, Avenue de la Gare 9, 1003 Lausanne (Switzerland); Richarme, Delphine [Institute of Radiology, Clinique Hirslanden Bois-Cerf, Avenue d’Ouchy 31, 1006 Lausanne (Switzerland); Meuli, Reto [Department of Diagnostic and Interventional Radiology, Centre Hospitalier Universitaire Vaudois, University of Lausanne, Rue du Bugnon 46, 1011 Lausanne (Switzerland); Becce, Fabio, E-mail: fabio.becce@chuv.ch [Department of Diagnostic and Interventional Radiology, Centre Hospitalier Universitaire Vaudois, University of Lausanne, Rue du Bugnon 46, 1011 Lausanne (Switzerland)

    2013-10-01

    Purpose: To determine the value of applying finger trap distraction during direct MR arthrography of the wrist to assess intrinsic ligament and triangular fibrocartilage complex (TFCC) tears. Materials and methods: Twenty consecutive patients were prospectively investigated by three-compartment wrist MR arthrography. Imaging was performed with 3-T scanners using a three-dimensional isotropic (0.4 mm) T1-weighted gradient-recalled echo sequence, with and without finger trap distraction (4 kg). In a blind and independent fashion, two musculoskeletal radiologists measured the width of the scapholunate (SL), lunotriquetral (LT) and ulna-TFC (UTFC) joint spaces. They evaluated the amount of contrast medium within these spaces using a four-point scale, and assessed SL, LT and TFCC tears, as well as the disruption of Gilula's carpal arcs. Results: With finger trap distraction, both readers found a significant increase in width of the SL space (mean Δ = +0.1 mm, p ≤ 0.040), and noticed more contrast medium therein (p ≤ 0.035). In contrast, the differences in width of the LT (mean Δ = +0.1 mm, p ≥ 0.057) and UTFC (mean Δ = 0 mm, p ≥ 0.728) spaces, as well as the amount of contrast material within these spaces were not statistically significant (p = 0.607 and ≥0.157, respectively). Both readers detected more SL (Δ = +1, p = 0.157) and LT (Δ = +2, p = 0.223) tears, although statistical significance was not reached, and Gilula's carpal arcs were more frequently disrupted during finger trap distraction (Δ = +5, p = 0.025). Conclusion: The application of finger trap distraction during direct wrist MR arthrography may enhance both detection and characterisation of SL and LT ligament tears by widening the SL space and increasing the amount of contrast within the SL and LT joint spaces.

  2. NMR studies in the half-Heusler type compound YbPtSb

    Energy Technology Data Exchange (ETDEWEB)

    Koyama, T; Abe, M; Mito, T; Ueda, K; Kohara, T [Graduate School of Material Science, University of Hyogo, Kamigori, Hyogo 678-1297 (Japan); Suzuki, H S, E-mail: t-koyama@sci.u-hyogo.ac.jp [National Institute for Materials Science, Tsukuba 305-0047 (Japan)

    2011-01-01

    {sup 121}Sb and {sup 19B}Pt nuclear magnetic resonance (NMR) has been studied in the half-Heusler type compound YbPtSb to obtain information on local magnetic behavior. The characteristics of the localized 4f spins are observed in the Cuire-Weiss type behavior of the Knight shifts K for both {sup 121}Sb and {sup 19B}Pt. From the slope of K-{sub {chi}} plots we estimated hyperfine coupling constants of -3.8 and -4.6 kOe/{mu}{sub B} at Sb and Pt sites, respectively. It was found that the spin-echo decay rate 1/T{sub 2} of {sup 121}Sb shows a clear peaks at 10 K. Similar tendency was also observed in case of {sup 19B}Pt. However, static properties do not show any anomalies near 10 K.

  3. Magnetic anisotropy, damping, and interfacial spin transport in Pt/LSMO bilayers

    Directory of Open Access Journals (Sweden)

    H. K. Lee

    2016-05-01

    Full Text Available We report ferromagnetic resonance measurements of magnetic anisotropy and damping in epitaxial La0.7Sr0.3MnO3 (LSMO and Pt capped LSMO thin films on SrTiO3 (001 substrates. The measurements reveal large negative perpendicular magnetic anisotropy and a weaker uniaxial in-plane anisotropy that are unaffected by the Pt cap. The Gilbert damping of the bare LSMO films is found to be low α = 1.9(1 × 10−3, and two-magnon scattering is determined to be significant and strongly anisotropic. The Pt cap increases the damping by 50% due to spin pumping, which is also directly detected via inverse spin Hall effect in Pt. Our work demonstrates efficient spin transport across the Pt/LSMO interface.

  4. Pt/C Fuel Cell Catalyst Degradation

    DEFF Research Database (Denmark)

    Zana, Alessandro

    This thesis investigates the degradation behavior of Pt/C catalysts under simulated automotive conditions. By using the “tool box” synthesis method the Pt loading has been changed from low to high Pt loadings, therefore permitting to study the role of Pt on the degradation of high surface area (H...

  5. Pt/C Fuel Cell Catalyst Degradation

    DEFF Research Database (Denmark)

    Zana, Alessandro

    This thesis investigates the degradation behavior of Pt/C catalysts under simulated automotive conditions. By using the “tool box” synthesis method the Pt loading has been changed from low to high Pt loadings, therefore permitting to study the role of Pt on the degradation of high surface area (H...

  6. Study on the preparation of Pt nanocapsules

    Science.gov (United States)

    Zhang, Yi-fan; Ji, Zhen; Chen, Ke; Liu, Bo-wen; Jia, Cheng-chang; Yang, Shan-wu

    2017-01-01

    Ag@Pt core-shell nanoparticles (Ag@Pt NPs) were prepared by a co-reduction method. Pt nanocapsules with diameters of less than 10 nm were obtained by an electrochemical method. Cyclic voltammetry (CV) scanning was used to cavitate the Ag@Pt NPs, and the morphology, structure, and cavitation conditions were studied. The results indicate that the effective cavitation conditions to obtain Pt nanoparticles from Ag@Pt NPs are a scanning voltage of 0 to 0.8 V and continuous CV scanning over 2 h. This cavitation method is also applicable for the syntheses of Ir, Ru, and Ru-Pt nanocapsules.

  7. MR-arthrography of the acetabular labrum - radiologic-pathologic correlation in 20 cadaveric hip joints; MR-Arthrographie des Labrum acetabulare - Radiologisch-anatomische Korrelation an 20 Leichenhueften

    Energy Technology Data Exchange (ETDEWEB)

    Brossmann, J.; Steffens, J.C.; Heller, M. [Kiel Univ. (Germany). Klinik fuer Diagnostische Radiologie; Ploetz, G.M.J.; Hassenpflug, J. [Kiel Univ. (Germany). Klinik fuer Orthopadie

    1999-08-01

    Purpose: To investigate frequency of acetabular labral lesions in elderly hip joints, and to determine sensitivity and specificity of MR arthrography (MRa) for the detection of these abnormalities. Materials and Methods: Twenty cadaveric hip joints were examined by MRa. For MRa, 15 ml of a solution of iodinated contrast solution (Solutrast 300) and Gd-DTPA (100:1) were injected under fluoroscopic guidance. MR imaging was performed on a 1.5 TM scanner (Vision, Siemens; FOV 16 cm, matrix 256x256, fat-suppressed 3D-FLASH). Multiplanar image reconstructions were done perpendicular to the acetabulum in the oblique-coronal, oblique-axial, and radial planes. The labral specimens were examined macroscopically. Results: In 12/20 hips (60%), a labral lesion was found on pathologic examination. In 7 specimens, the labrum was partially or completely detached in the weight-bearing superior region. One flap-like variant of the labrum was seen; in 4 hip joints, the labrum was degenerated (one cystic degeneration). Pathologic findings were confirmed by MRa in 8/12 specimens (sensitivity 67%). All degenerated labra were correctly diagnosed on MRa. Three small labral detachments and the flap-like variant were misinterpreted as being normal. There were no false positive findings (specificity 100%). The accuracy was 80%. Labral lesions were seen in 6/8 and in 6/12 of hips with and without osteoarthritis, respectively. Conclusion: MRa is well suited to delineate the acetabular labrum and to diagnose labral abnormalities. Detection of small labral detachments and anatomic variants is difficult and requires some experience. Labral lesions are correlated to osteoarthritis of the hip, but may be frequently seen in the elderly without underlying osteoarthritis. (orig.) [German] Ziel: Feststellung der Haeufigkeit von Laesionen des Labrum acetabulare bei aelteren Hueftgelenkspraeparaten und Untersuchung der Sensitivitaet und Spezifitaet der MR-Arthrographie (MRa) fuer die Darstellung dieser

  8. Magnetic resonance imaging in glenohumeral instability

    Science.gov (United States)

    Jana, Manisha; Gamanagatti, Shivanand

    2011-01-01

    The glenohumeral joint is the most commonly dislocated joint of the body and anterior instability is the most common type of shoulder instability. Magnetic resonance (MR) imaging, and more recently, MR arthrography, have become the essential investigation modalities of glenohumeral instability, especially for pre-procedure evaluation before arthroscopic surgery. Injuries associated with glenohumeral instability are variable, and can involve the bones, the labor-ligamentous components, or the rotator cuff. Anterior instability is associated with injuries of the anterior labrum and the anterior band of the inferior glenohumeral ligament, in the form of Bankart lesion and its variants; whereas posterior instability is associated with reverse Bankart and reverse Hill-Sachs lesion. Multidirectional instability often has no labral pathology on imaging but shows specific osseous changes such as increased chondrolabral retroversion. This article reviews the relevant anatomy in brief, the MR imaging technique and the arthrographic technique, and describes the MR findings in each type of instability as well as common imaging pitfalls. PMID:22007285

  9. Pt···Pt vs Pt···S contacts between Pt-containing heterobimetallic lantern complexes.

    Science.gov (United States)

    Baddour, Frederick G; Fiedler, Stephanie R; Shores, Matthew P; Bacon, Jeffrey W; Golen, James A; Rheingold, Arnold L; Doerrer, Linda H

    2013-12-01

    A trio of Pt-based heterobimetallic lantern complexes of the form [(py)PtM(SAc)4(py)] (M = Co, 1; Ni, 2; Zn, 3) with unusual octahedral coordination of Pt(II) was prepared from a reaction of [PtM(SAc)4] with excess pyridine. These dipyridine lantern complexes could be converted to monopyridine derivatives with gentle heat to give the series [PtM(SAc)4(py)] (M = Co, 4; Ni, 5; Zn, 6). An additional family of the form [PtM(SAc)4(pyNH2)] (M = Co, 7; Ni, 8; Zn, 9) was synthesized from reaction of [PtM(SAc)4(OH2)] or [PtM(SAc)4] with 4-aminopyridine. Dimethylsulfoxide and N,N-dimethylformamide were also determined to react with [PtM(SAc)4] (M = Co, Ni), respectively, to give [PtCo(SAc)4(DMSO)](DMSO), 10, and [PtNi(SAc)4(DMF)](DMF), 11. Structural and magnetic data for these compounds and those for two other previously published families, [PtM(tba)4(OH2)] and [PtM(SAc)4(L)], L = OH2, pyNO2, are used to divide the structures among three distinct categories based on Pt···Pt and Pt···S distances. In general, the weaker donors H2O and pyNO2 seem to favor metallophilicity and antiferromagnetic coupling between 3d metal centers. When Pt···S interactions are favored over Pt···Pt ones, no coupling is observed and the pKa of the pyridine donor correlates with the interlantern S···S distance. UV-vis-NIR electronic and (1)H NMR spectra provide complementary characterization as well.

  10. Premature temporal theta (PT theta).

    Science.gov (United States)

    Hughes, J R; Fino, J J; Hart, L A

    1987-07-01

    A distinctive pattern called premature temporal theta (PT theta) was studied in 436 infants, ranging in age from 24 to 46 weeks. The pattern is seen in early prematurity, maximizes at 29-31 weeks and then diminishes and disappears near term. Usually the pattern is found independently on both temporal areas, but with a right-sided preference. Patients without PT theta or with a significantly low amount had either neurological or non-neurological (medical) conditions. With age there is a tendency for an increase in frequency and a decrease in amplitude. Five different peaks in the amount of this pattern are seen at approximately every month. Unilateral PT theta tends to be seen in older babies, more often on the right side and with an abnormal EEG. An abnormal EEG is usually associated with a delay in both the appearance and disappearance of this wave form. PT theta is also associated mainly with REM or active sleep. A polynomial rather than an exponential or power function best describes these data with changes of age. PT theta may arise from the inferior temporal gyrus and/or especially the transverse gyrus.

  11. Effect of Pt coverage in Pt-deposited Pd nanostructure electrodes on electrochemical properties

    Energy Technology Data Exchange (ETDEWEB)

    Park, Ah-Reum; Lee, Young-Woo; Kwak, Da-Hee; Park, Kyung-Won [Soongsil University, Seoul (Korea, Republic of)

    2015-06-15

    We have fabricated Pt-deposited Pd electrodes via a two-gun sputtering deposition system by separately operating Pd and Pt target as a function of sputtering time of Pt target. For Pt-deposited Pd electrodes (Pd/Pt-X), Pd were first deposited on the substrates at 20 W for 5min, followed by depositing Pt on the Pd-only electrodes as a function of sputtering time (X=1, 3, 5, 7, and 10min) at 20W on the Pt target. As the sputtering time of Pt target increased, the portion of Pt on the Pd electrodes increased, representing an increased coverage of Pt on the Pd electrodes. The Pd/Pt-7 electrode having an optimized Pt coverage exhibits an excellent electrocatalytic activity for methanol oxidation reaction.

  12. Au@Pt nanostructures: a novel photothermal conversion agent for cancer therapy.

    Science.gov (United States)

    Tang, Jinglong; Jiang, Xiumei; Wang, Liming; Zhang, Hui; Hu, Zhijian; Liu, Ying; Wu, Xiaochun; Chen, Chunying

    2014-04-07

    Due to aspect ratio dependent localized surface plasmon resonance (SPR), gold nanorods (Au NRs) can be tuned to have a strong absorption in the near infrared region (NIR) and convert light to heat energy, which shows promises in cancer photothermal therapy. In this study, we introduced another more efficient NIR photothermal agent, Au nanorods coated with a shell of Pt nanodots (Au@Pt nanostructures). After surface modification with Pt dots, the Au@Pt nanostructure became a more efficient photothermal therapy agent as verified both in vitro and in vivo. To clarify the mechanism, we assessed the interaction between the MDA-MB-231 cells with Au@Pt or Au NRs. Results showed that the slightly higher uptake and the reduced sensitivity of the longitudinal SPR band on the intracellular aggregate state may contribute to the better photothermal efficiency for Au@Pt NRs. The theoretical studies further confirmed that the Au@Pt nanostructure itself exhibited better photothermal efficiency compared to Au NRs. These advantages make the Au@Pt nanostructure a more attractive and effective agent for cancer photothermal therapy than general Au NRs.

  13. Au-Pt alloy nanoparticles obtained by nanosecond laser irradiation of gold and platinum bulk targets in an ethylene glycol solution

    Science.gov (United States)

    Moniri, Samira; Reza Hantehzadeh, Mohammad; Ghoranneviss, Mahmood; Asadi Asadabad, Mohsen

    2017-07-01

    Au-Pt alloy nanoparticles (NPs) of different compositions ( Au0Pt100 , Au30Pt70 , Au50Pt50 , Au70Pt30 , and Au100Pt0 were obtained using the nanosecond laser ablation of gold and platinum bulk targets in ethylene glycol, followed by mixing highly monodisperse Au and Pt nanocolloids, for the first time. UV-vis absorption spectra of NPs showed that by increasing the Au content in the Au-Pt NPs, the surface plasmon resonance (SPR) peak red-shifted, from 260 to 573nm in a nonlinear way. In addition, the mean crystalline size, crystal structure, d-spacing, and lattice parameters of NPs were estimated from the XRD spectra. Microscopy studies revealed the most NPs have a spherical or near-spherical shape, and the average sizes of Au0Pt100 , Au30Pt70 , Au50Pt50 , Au70Pt30 , and Au100Pt0 NPs were calculated to be 12.50, 14.15, 18.53, 19.29, and 26.38nm, respectively. Also, the chemical identity of the molecules adhering to the NPs surface was considered by Raman and FT-IR spectroscopy techniques. Among different synthesis methods, the demonstrated technique allows easy synthesis of alloy NPs in aqueous media at room temperature with no formation of by-products.

  14. Electron transport in a Pt-CO-Pt nanocontact: Density functional theory calculations

    DEFF Research Database (Denmark)

    Strange, Mikkel; Thygesen, Kristian Sommer; Jacobsen, Karsten Wedel

    2006-01-01

    We have performed first-principles calculations for the mechanic and electric properties of pure Pt nanocontacts and a Pt contact with a single CO molecule adsorbed. For the pure Pt contacts we see a clear difference between point contacts and short chains in good agreement with experiments. We i...... of the transmission function for the Pt-CO-Pt contact, and show that the conductance is largely determined by the local d band at the Pt apex atoms....

  15. Optimization of computed tomography (CT) arthrography of hip for the visualization of cartilage: an in vitro study

    Energy Technology Data Exchange (ETDEWEB)

    Simoni, Paolo; Leyder, Pierre-Philippe; Malchair, Francoise; Marechal, Carole; Alvarez Miezentseva, Victoria [CHU de Liege, Diagnostic Imaging Department, MSK Imaging, Liege (Belgium); Albert, Adelin [CHU de Liege, Biostatistics Department, Liege (Belgium); Scarciolla, Laura; Beomonte Zobel, Bruno [Campus Bio-Medico University, Diagnostic Imaging Department, Rome (Italy); Gillet, Philippe [CHU de Liege, Orthopaedic Surgery Department, Liege (Belgium)

    2014-02-15

    We sought to optimize the kilovoltage, tube current, and the radiation dose of computed tomographic arthrography of the hip joint using in vitro methods. A phantom was prepared using a left femoral head harvested from a patient undergoing total hip arthroplasty and packed in a condom filled with iodinated contrast. The right hip joint of a cadaver was also injected with iodinated contrast. The phantom and the cadaver were scanned using different values of peak kilovoltage (kVp) and tube current (milliamp seconds, mAs). Three different regions of interest (ROI) were drawn in the cartilage, subchondral bone plate, and intraarticular contrast. The attenuation values, contrast/noise ratio (CNR), and effective dose were calculated. Two independent observers classified the quality of the contrast-cartilage interface and the cartilage-subchondral bone plate interface as (1) diagnostic quality or (2) nondiagnostic quality. Contrast, cartilage, and subchondral bone plate attenuation values decreased at higher kVp. CNR increased with both kVp and mAs. The qualitative analysis showed that in both phantom and cadaver, at 120 kVp and 50 mAs, the contrast-cartilage and cartilage-subchondral bone plate interfaces were of diagnostic quality, with an effective dose decreased to 0.5 MSv. The absolute effective dose is not directly related to the quality of images but to the specific combination of kVp and mAs used for image acquisition. The combination of 120 kVp and 50 mAs can be suggested to decrease the dose without adversely affect the visibility of cartilage and subchondral bone plate. (orig.)

  16. Usefulness of intra-articular bupivacain and lidocain adjunction in MR or CT arthrography: A prospective study in 148 patients

    Energy Technology Data Exchange (ETDEWEB)

    Mosimann, Pascal J., E-mail: pascal.mosimann@chuv.ch [Department of Diagnostic and Interventional Radiology, Centre Hospitalier Universitaire Vaudois, University of Lausanne, Rue du Bugnon 46, 1011 Lausanne (Switzerland); Richarme, Delphine; Becce, Fabio; Knoepfli, Anne-Sophie; Mino, Vincent; Meuli, Reto [Department of Diagnostic and Interventional Radiology, Centre Hospitalier Universitaire Vaudois, University of Lausanne, Rue du Bugnon 46, 1011 Lausanne (Switzerland); Theumann, Nicolas [Department of Radiology, Clinique Hirslanden Bois-Cerf, 1006 Lausanne (Switzerland)

    2012-09-15

    Purpose: To evaluate the influence of shorter- and longer-acting intra-articular anaesthetics on post-arthrographic pain. Materials and methods: 154 consecutive patients investigated by MR or CT arthrographies were randomly assigned to one of the following groups: 1 – intra-articular contrast injection only; 2 – lidocain 1% adjunction; or 3 – bupivacain 0.25% adjunction. Pain was assessed before injection, at 15 min, 4 h, 1 day and 1 week after injection by visual analogue scale (VAS). Results: At 15 min, early mean pain score increased by 0.96, 0.24 and 0 in groups 1, 2 and 3, respectively. Differences between groups 1 and 3 and 1 and 2 were statistically significant (p = 0.003 and 0.03, respectively), but not between groups 2 and 3 (p = 0.54). Delayed mean pain score increase was maximal at 4 h, reaching 1.60, 1.22 and 0.29 in groups 1, 2 and 3, respectively. Differences between groups 1 and 2 and 2 and 3 were statistically significant (p = 0.002 and 0.02, respectively), but not between groups 1 and 2 (p = 0.46). At 24 h and 1 week, the interaction of local anaesthetics with increase in pain score was no longer significant. Results were independent of age, gender and baseline VAS. Conclusion: Intra-articular anaesthesia may significantly reduce post-arthrographic pain. Bupivacain seems to be more effective than lidocain to reduce both early and delayed pain.

  17. Advantage analysis of PMN-PT material for free-flooded ring transducers

    Institute of Scientific and Technical Information of China (English)

    He Zheng-Yao; Ma Yuan-Liang

    2011-01-01

    The acoustic radiation characteristics of free-flooded ring transducers made of PZT4 and PMN-PT materials are calculated and compared.First,the theoretical formulae for free-flooded ring transducers are studied.The resonant frequencies of a transducer made of PZT4 and PMN-PT materials are calculated. Then,the transmitting voltage responses of the free-flooded ring transducers are calculated using the finite element method.Finally,the acoustic radiation characteristics of the free-flooded ring transducers are calculated using the boundary element method.The calculated results show that the resonant frequencies of the free-flooded ring transducer made of PMN-PT are greatly reduced compared with those made of PZT4 with the same size.The transmitting voltage response of the transducer made of PMN-PT is much higher than that of the transducer made of PZT4.The calculated 3-dB beamwidth of the acoustic radiated far-field directivity of the free-flooded ring transducer made of PZT4 at the resonant frequency 1900 Hz is 63.6° and that of the transducer made of PMN-PT at the resonant frequency 1000 Hz is 64.6°.The comparison results show that the free-flooded ring transducer made of PMN-PT material has many advantages over that made of PZT4.The PMN-PT is a promising material for improving the performance of free-flooded ring transducers.

  18. PT-Symmetric Nonlinear Metamaterials and Zero-Dimensional Systems

    CERN Document Server

    Tsironis, G P

    2013-01-01

    A one dimensional, parity-time (${\\cal PT}$)-symmetric magnetic metamaterial comprising split-ring resonators having both gain and loss is investigated. In the linear regime, the transition from the exact to the broken ${\\cal PT}$-phase is determined through the calculation of the eigenfrequency spectrum for two different configurations; the one with equidistant split-rings and the other with the split-rings forming a binary pattern (${\\cal PT}$ dimer chain). The latter system features a two-band, gapped spectrum with its shape determined by the gain/loss coefficient as well as the inter-element coupling. In the presense of nonlinearity, the ${\\cal PT}$ dimer chain with balanced gain and loss supports nonlinear localized modes in the form of novel discrete breathers below the lower branch of the linear spectrum. These breathers, that can be excited from a weak applied magnetic field by frequency chirping, can be subsequently driven solely by the gain for very long times. The effect of a small imbalance betwee...

  19. Electrodeposited CoPt and FePt alloys nanowires

    Energy Technology Data Exchange (ETDEWEB)

    Cagnon, L. [Laboratoire de Cristallographie, CNRS, BP 166, 38042 Grenoble cedex 9 (France)]. E-mail: laurent.cagnon@grenoble.cnrs.fr; Dahmane, Y. [Laboratoire Louis Neel, CNRS, BP 166, 38042 Grenoble cedex 9 (France); Laboratoire de Materiaux, Electrochimie et Corrosion, BP 17, 15000 Tizi-Ouzou (Algeria); Voiron, J. [Laboratoire Louis Neel, CNRS, BP 166, 38042 Grenoble cedex 9 (France); Pairis, S. [Laboratoire de Cristallographie, CNRS, BP 166, 38042 Grenoble cedex 9 (France); Bacia, M. [Laboratoire de Cristallographie, CNRS, BP 166, 38042 Grenoble cedex 9 (France); Ortega, L. [Laboratoire de Cristallographie, CNRS, BP 166, 38042 Grenoble cedex 9 (France); Benbrahim, N. [Laboratoire de Materiaux, Electrochimie et Corrosion, BP 17, 15000 Tizi-Ouzou (Algeria); Kadri, A. [Laboratoire de Materiaux, Electrochimie et Corrosion, BP 17, 15000 Tizi-Ouzou (Algeria)

    2007-03-15

    We have investigated CoPt and FePt alloys with the face centered tetragonal phase L10, which present very large magnetocrystalline anisotropy. Equiatomic CoPt nanowires exhibiting large coercive fields up to 1.1 T have been successfully prepared by electrodeposition into nanopores of commercial and home-made alumina membranes from a very simple electrolyte. The as-deposited material has the FCC structure with soft magnetic properties. An annealing treatment at 700 deg. C is crucial to transform this phase into the L1{sub 0} phase, which presents hard magnetic properties. Nanowires of annealed samples consist of small grains around 20 nm, with their c axes randomly distributed. The coercivity does not depend on the morphology and porosity of the two types of membranes but only on the deposited material elaborated with the appropriate thermal annealing process. Our preliminary results with FePt alloy indicate a more complicated system since the as-deposited material shows no magnetization. Magnetism appears only after annealing at 700-750 deg. C. Coercivity up to 0.85 T has been obtained at room temperature but with inhomogeneous phase composition. To achieve a single hard phase L1{sub 0}, it is essential to get for the as-deposited sample the equiatomic composition and then to employ the suitable annealing parameters (temperature and time) to change the whole FCC phase into the FCT ordered L1{sub 0} phase.

  20. Pseudomeningocele in communication with the facet joint: demonstration by computerized tomography-arthrography

    Energy Technology Data Exchange (ETDEWEB)

    Ganiyusufoglu, Kursat; Ozturk, Cagatay; Sirvanci, Mustafa; Aksu, Neslihan; Hamzaoglu, Azmi [Florence Nightingale Hospital, Istanbul Bilim University, Istanbul Spine Center, Istanbul (Turkey)

    2008-08-15

    Pseudomeningocele is an uncommon but well-known complication of lumbar spine operations. Although it is mostly asymptomatic and managed conservatively in most cases, it is claimed as a causative factor of failed back surgery syndrome and requires surgery in some cases. Usually, its diagnosis is confidently done with imaging modalities such as magnetic resonance imaging, computed tomography and myelography. In this report, we describe a case of pseudomeningocele that communicated with a facet joint. The diagnostic approach for this unusual lesion and its probable causes are discussed. (orig.)

  1. Spatially resolved energy dispersive x-ray spectroscopic method for in-situ evaluation of mechanical properties during the growth of a C - Pt composite nanowire

    Energy Technology Data Exchange (ETDEWEB)

    Banerjee, Amit; Banerjee, S. S., E-mail: satyajit@iitk.ac.in [Department of Physics, Indian Institute of Technology Kanpur, Kanpur, 208016 (India)

    2014-05-15

    A core-shell type C-Pt composite nanowire is fabricated using focused ion and electron beam induced chemical vapor deposition techniques. Using information from spatially resolved energy dispersive x-ray spectra, we detect the resonance vibration in the C-Pt composite nanowire. We use this method to measure the Young's moduli of the constituents (C, Pt) of the composite nanowire and also estimate the density of the FEB CVD grown Pt shell surrounding the C core. By measuring the resonance characteristics of the composite nanowire we estimate a Pt shell growth rate of ∼0.9 nms{sup −1}. The study is analyzed to suggest that the Pt shell growth mechanism is primarily governed by the sticking coefficient of the organometallic vapor on the C nanowire core.

  2. Ab-initio study of the coadsorption of Li and H on Pt(001), Pt(110) and Pt(111) surfaces

    Energy Technology Data Exchange (ETDEWEB)

    Saad, Farida [Laboratoire de Physique et Chimie Quantique, Faculte des Sciences, Universite Mouloud Mammeri, 15000 Tizi-Ouzou (Algeria); Zemirli, Mourad, E-mail: zemirlimourad@mail.ummto.dz [Laboratoire de Physique et Chimie Quantique, Faculte des Sciences, Universite Mouloud Mammeri, 15000 Tizi-Ouzou (Algeria); Benakki, Mouloud; Bouarab, Said [Laboratoire de Physique et Chimie Quantique, Faculte des Sciences, Universite Mouloud Mammeri, 15000 Tizi-Ouzou (Algeria)

    2012-02-15

    The coadsorption of Li and H atoms on Pt(001), Pt(110) and Pt(111) surfaces is studied using density functional theory with generalised gradient approximation. In all calculations Li, H and the two topmost layers of the metal were allowed to relax. At coverage of 0.25 mono-layer in a p(2 Multiplication-Sign 2) unit cell, lithium adsorption at the hollow site for the three surfaces is favoured over top and bridge sites. The most favoured adsorption sites for H atom on the Pt(001) and Pt(110) surfaces are the top and bridge sites, while on Pt(111) surface the fcc site appears to be slightly favoured over the hcp site. The coadsorption of Li and atomic hydrogen shows that the interaction between the two adsorbates is stabilising when they are far from each other. The analysis of Li, H and Pt local density of states shows that Li strongly interacts with the Pt surfaces.

  3. PT-symmetric quantum theory

    Science.gov (United States)

    Bender, Carl M.

    2015-07-01

    The average quantum physicist on the street would say that a quantum-mechanical Hamiltonian must be Dirac Hermitian (invariant under combined matrix transposition and complex conjugation) in order to guarantee that the energy eigenvalues are real and that time evolution is unitary. However, the Hamiltonian H = p2 + ix3, which is obviously not Dirac Hermitian, has a positive real discrete spectrum and generates unitary time evolution, and thus it defines a fully consistent and physical quantum theory. Evidently, the axiom of Dirac Hermiticity is too restrictive. While H = p2 + ix3 is not Dirac Hermitian, it is PT symmetric; that is, invariant under combined parity P (space reflection) and time reversal T. The quantum mechanics defined by a PT-symmetric Hamiltonian is a complex generalization of ordinary quantum mechanics. When quantum mechanics is extended into the complex domain, new kinds of theories having strange and remarkable properties emerge. In the past few years, some of these properties have been verified in laboratory experiments. A particularly interesting PT-symmetric Hamiltonian is H = p2 - x4, which contains an upside-down potential. This potential is discussed in detail, and it is explained in intuitive as well as in rigorous terms why the energy levels of this potential are real, positive, and discrete. Applications of PT-symmetry in quantum field theory are also discussed.

  4. Differences between radial and ulnar deviation of the wrist in the study of the intrinsic intercarpal ligaments: magnetic resonance imaging and gross anatomic inspection in cadavers

    Energy Technology Data Exchange (ETDEWEB)

    Gheno, Ramon; Buck, Florian M.; Nico, Marcelo A.C.; Trudell, Debra J.; Resnick, Donald [VA San Diego Medical Center, Department of Radiology, San Diego, CA (United States)

    2010-08-15

    To demonstrate how radial and ulnar deviation of the wrist can affect the visualization of the intrinsic intercarpal ligaments using magnetic resonance (MR) imaging, MR arthrography and gross anatomic inspection in cadavers. The detectability of the intrinsic intercarpal ligaments of ten fresh human wrists was analyzed in coronal, axial and sagittal images in the neutral position and in radial and ulnar deviation with MR imaging and MR arthrography. The findings were then correlated with gross anatomic inspection. Additionally, quantitative measurements including the radiocarpal distances and capitate angles were performed. Differences were noted in the visual conspicuity of only the intercarpal ligaments of the proximal carpal row with different techniques and wrist positions. The average width of the radiocarpal joint was 0.62 mm, 1.55 mm and 2.0 mm (radial side) and 3.78 mm, 2.25 mm and 1.16 mm (ulnar side) in radial deviation, neutral position, and ulnar deviation of the wrist, respectively. Statistically, these maneuvers produced significant opening in the ulnar side during radial deviation (Student's t-test; P = 0.0005) and in the radial side in ulnar deviation (P = 0.007). Significant differences in the width of the radiocarpal joint were observed during radial and ulnar deviation of the wrist, influencing the visualization of the intrinsic ligaments, mainly the scapholunate and lunotriquetral ligaments. The use of MR arthrography with radial and/or ulnar deviation has the potential to improve diagnosis in clinical cases in which injury to one or both of these ligaments is suggested. (orig.)

  5. Multi-color imaging of magnetic Co/Pt heterostructures

    Directory of Open Access Journals (Sweden)

    Felix Willems

    2017-01-01

    Full Text Available We present an element specific and spatially resolved view of magnetic domains in Co/Pt heterostructures in the extreme ultraviolet spectral range. Resonant small-angle scattering and coherent imaging with Fourier-transform holography reveal nanoscale magnetic domain networks via magnetic dichroism of Co at the M2,3 edges as well as via strong dichroic signals at the O2,3 and N6,7 edges of Pt. We demonstrate for the first time simultaneous, two-color coherent imaging at a free-electron laser facility paving the way for a direct real space access to ultrafast magnetization dynamics in complex multicomponent material systems.

  6. Imaging of the knee joint with emphasis on magnetic resonance imaging

    Energy Technology Data Exchange (ETDEWEB)

    Reiser, M.F. [Radiologische Universitaetsklinik, Rheinische Friedrich-Wilhelms-Univ., Bonn (Germany); Vahlensieck, M. [Radiologische Universitaetsklinik, Rheinische Friedrich-Wilhelms-Univ., Bonn (Germany); Schueller, H. [Radiologische Universitaetsklinik, Rheinische Friedrich-Wilhelms-Univ., Bonn (Germany)

    1992-04-01

    The knee joint is frequently affected by trauma as well as degenerative and inflammatory disorders, involving the internal structures (i.e. ligaments, menisci, cartilage, synovial membrane) and the adjacent bones. Plain radiographs represent an indispensable basis for diagnosis. For further analysis magnetic resonance imaging (MRI) has become the method of choice, and has widely replaced computed tomography, arthrography and stress examinations. Extensive experience has been accumulated in MRI of the knee joint in recent years. In addition, advances in MRI technology have had a major impact on diagnostic accuracy. In this paper, diagnosis of various lesions of the knee joint, such as meniscal and ligamental injuries, aseptic necrosis, lesions of the hyaline cartilage, occult fractures and inflammatory lesions will be discussed. (orig.)

  7. Recent hadronic resonance measurements at ALICE

    CERN Document Server

    Knospe, A.G.

    2016-01-01

    In heavy-ion physics, measurements of short-lived hadronic resonances allow the properties of the hadronic phase of the collision to be studied. In addition, resonances can be used along with stable hadrons to study parton energy loss in the quark-gluon plasma and the mechanisms that shape hadron pT spectra at intermediate transverse momenta. Resonance measurements in small systems serve as a reference for heavy-ion collisions and contribute to searches for collective effects. An overview of recent results on hadronic resonance production measured in ALICE is presented. These results include the pT spectra and yields of the rho(770)0, K*(892)0, and phi(1020) mesons in pp, p-Pb, and Pb-Pb collisions at different energies as well as the Sigma(1385)+/- and Xi(1530)0 baryons in pp and p-Pb collisions.

  8. Results of the Proficiency Test, PT1 and PT2, 2012

    DEFF Research Database (Denmark)

    Vendramin, Niccolò; Nicolajsen, Nicole; Christophersen, Maj-Britt

    A comparative test of diagnostic procedures was provided by the European Union Reference Laboratory (EURL) for Fish Diseases. The test was divided into proficiency test 1 (PT1) and proficiency test 2 (PT2). The number of National Reference Laboratories (NRLs) participating in PT1 and PT2 was 43...

  9. Oxygen reduction activity of Pt and Pt-alloys in acid electrolyte

    Energy Technology Data Exchange (ETDEWEB)

    Paulus, Ursula A. [Paul Scherrer Inst., CH-5232 Villigen PSI (Switzerland); Schmidt, Thomas J.; Stamenkovic, Vojislav R.; Markovic, Nenad M.; Ross, Philip N. [Material Science Division, Lawrence Berkeley National Laboratory, University of California, Berkeley, CA 94720 (United States)

    2001-07-01

    The oxygen reduction reaction (ORR) has been studied on polycrystalline (pc) Pt, Pt{sub 3}Ni and Pt{sub 3}Co bulk alloy electrodes and on carbon supported Pt, PtNi and PtCo alloy catalysts. Base voltammetry measurements as well as complementary Auger Electron Spectroscopy (AES) and Low Energy Ion Scattering (LEIS) on bulk electrodes and High Resolution Transmission Electron Microscopy (HRTEM)-analysis on the supported catalysts allow an estimation of the surface composition. By using the rotating ring-disk electrode (RRDE) technique both the kinetic analysis of the ORR and in parallel the detection and quantification of the amount of peroxide produced during the ORR are possible. The activity for the ORR increases in the order Pt < Pt{sub 3}Ni < Pt{sub 3}Co for equally prepared bulk alloys and Pt < Pt{sub 3}Ni {approx} Pt{sub 3}CO < PtCo for the carbon supported catalysts, respectively. It was proposed that the mechanism for the ORR is the same on pure Pt and the PtNi and PtCo alloys. (author)

  10. Hydrogen Adsorption on Pt, Rh and Pt-Rh Electrodes

    Institute of Scientific and Technical Information of China (English)

    贾梦秋; A.M.Meretskyi

    2005-01-01

    The hydrogen adsorption on Pt-Rh alloys in sulfuric acid aqueous solutions was studied by the method of cathode pulses. Hydrogen adsorption on the electrode with all ratio of alloy components (ωRh = 0-100%) is well described by the Temkin logarithmic isotherm. The surface coverage by adsorbed hydrogen at the same potential is decreased with increasing content of rhodium in the system. A linear dependence of adsorption peak potential on the alloy compositions in the case of weakly bonded adsorbed hydrogen is established. Hydrogen adsorption heat as a function of surface coverage for Pt-Rh-electrodes was obtained. The shape of the current-potential curve and position of the weakly bonded hydrogen adsorption on the potential scale are all related to alloy compositions, thus can serve as the basis for the determination surface composition of allovs.

  11. Surface termination of CePt5/Pt (111 ): The key to chemical inertness

    Science.gov (United States)

    Praetorius, C.; Zinner, M.; Held, G.; Fauth, K.

    2015-11-01

    The surface termination of CePt5/Pt (111 ) is determined experimentally by LEED-IV. In accordance with recent theoretical predictions, a dense Pt terminated surface is being found. Whereas the CePt5 volume lattice comprises Pt kagome layers, additional Pt atoms occupy the associated hole positions at the surface. This finding provides a natural explanation for the remarkable inertness of the CePt5 intermetallic. Implications of the structural relaxations determined by LEED-IV analysis are discussed with regard to observations by scanning tunneling microscopy and electron spectroscopies.

  12. Studies of surface processes of electrocatalytic reduction of CO2 on Pt(210), Pt(310) and Pt(510)

    Institute of Scientific and Technical Information of China (English)

    FAN; ChunJie; FAN; YouJun; ZHEN; ChunHua; ZHENG; QingWei; SUN; ShiGang

    2007-01-01

    Surface processes of CO2 reduction on Pt(210), Pt(310), and Pt(510) electrodes were studied by cyclic voltammetry. Different surface structures of these platinum single crystal electrodes were obtained by various treatment conditions. The experimental results illustrated that the electrocatalytic activity of Pt single crystal electrodes towards CO2 reduction is decreased in an order of Pt(210)>Pt(310)>Pt(510), i.e., with the decrease of (110) step density on well-defined surfaces. When the surfaces were reconstructed due to oxygen adsorption, the catalytic activity of all the three electrodes has been enhanced to a certain extent. Although the activity order remains unchanged, the electrocatalytic activity has been enhanced more significantly as the density of (110) step sites is more intensive on the Pt single crystal surface. It has revealed that the more open the surface structure is, the more active the Pt single crystal electrode will be, and the easier for the electrode to be transformed into a surface structure that exhibits higher activity under external inductions. However, the relatively ordered surfaces of Pt single crystal electrode are comparatively stable under the same external inductions. The present study has gained knowledge on the interaction between CO2 and Pt single crystal electrode surfaces at a microscopic level, and thrown new insight into understanding the surface processes of electrocatalytic reduction of CO2.

  13. Characterization of spin pumping effect in Permalloy/Cu/Pt microfabricated lateral devices

    Energy Technology Data Exchange (ETDEWEB)

    Yamamoto, Tatsuya, E-mail: tyamamoto@imr.tohoku.ac.jp; Seki, Takeshi; Takanashi, Koki [Institute for Materials Research, Tohoku University, Sendai 980-8577 (Japan); Ono, Shimpei [Central Research Institute of Electric Power Industry, Tokyo 201-8511 (Japan)

    2014-05-07

    We studied ferromagnetic resonance (FMR) for microfabricated lateral devices consisting of a Permalloy (Py) rectangular element and a Pt nano-element bridged by a Cu wire, which were located on a coplanar waveguide. A change in the resonance linewidth (Δf) was observed in the FMR spectra when the distance between Py and Pt (d) was varied. For devices with d < 400 nm, Δf definitely increased, suggesting the enhancement of the Gilbert damping constant (α). We discussed a possible reason for the this enhancement taking into account the increase in the efficiency of spin pumping into Cu due to the spin absorption of the attached Pt.

  14. Highly active Pt3Pb and core-shell Pt3Pb-Pt electrocatalysts for formic acid oxidation.

    Science.gov (United States)

    Kang, Yijin; Qi, Liang; Li, Meng; Diaz, Rosa E; Su, Dong; Adzic, Radoslav R; Stach, Eric; Li, Ju; Murray, Christopher B

    2012-03-27

    Formic acid is a promising chemical fuel for fuel cell applications. However, due to the dominance of the indirect reaction pathway and strong poisoning effects, the development of direct formic acid fuel cells has been impeded by the low activity of existing electrocatalysts at desirable operating voltage. We report the first synthesis of Pt(3)Pb nanocrystals through solution phase synthesis and show they are highly efficient formic acid oxidation electrocatalysts. The activity can be further improved by manipulating the Pt(3)Pb-Pt core-shell structure. Combined experimental and theoretical studies suggest that the high activity from Pt(3)Pb and the Pt-Pb core-shell nanocrystals results from the elimination of CO poisoning and decreased barriers for the dehydrogenation steps. Therefore, the Pt(3)Pb and Pt-Pb core-shell nanocrystals can improve the performance of direct formic acid fuel cells at desired operating voltage to enable their practical application. © 2012 American Chemical Society

  15. PT Symmetry as a Generalization of Hermiticity

    CERN Document Server

    Wang, Qing-hai; Zhang, Jie-hong

    2010-01-01

    The Hilbert space in PT-symmetric quantum mechanics is formulated as a linear vector space with a dynamic weight function in the inner product. The most general PT-symmetric matrix Hamiltonians are constructed for 2*2 and 3*3 cases. In the former case, the PT-symmetric Hamiltonian represents the most general matrix Hamiltonian with a real spectrum. In both cases, the Hermitian matrix is shown to be a special case of PT-symmetric matrices. This finding confirms and strengthens the early belief that the PT-symmetric quantum mechanics is a generalization of the conventional Hermitian quantum mechanics.

  16. A radiologist`s guide to the imaging in the diagnosis and treatment of developmental dysplasia of the hip. Pt. 1. General considerations, physical examination as applied to real-time sonography and radiography

    Energy Technology Data Exchange (ETDEWEB)

    Gerscovich, E.O. [Department of Radiology, University of California, Davis Medical Center, 2516 Stockton Blvd., Ticon II Building, Sacramento, CA 95817 (United States)

    1997-07-07

    Developmental dysplasia of the hip (DDH) has a broad spectrum of presentation with the minor findings resolving spontaneously and the most severe ones resulting in disability, if not diagnosed early in life. Diagnosis in the first few months of life allows conservative treatment with complete resolution in most cases. Suspicion of DDH is based on ethnic, family, and pregnancy history, and on physical examination of the newborn. Imaging assists in the diagnosis and follows the treatment. Different modalities have their own advantages and disadvantages. This article deals with the description of the disease, risk factors, statistics, the physical examination as applied to real-time sonography, and imaging (plain radiography, arthrography, computed tomography, and magnetic resonance imaging). (orig.). With 26 figs., 1 tab.

  17. Chronic ankle instability: evaluation with stress radiography, CT and CT arthrography; Instabilite chronique externe de la cheville. Apport des radiographies dynamiques, de la tomodensitometrie et de l`arthro-tomodensitometrie

    Energy Technology Data Exchange (ETDEWEB)

    Faure, Ch.; Deplus, F.; Bochu, M. [Hopital Edouard-Herriot, 69 - Lyon (France); Besse, J.L.; Moyen, B. [Centre Hospitalier Lyon-Sud, 69 -Pierre-Benite (France)

    1997-09-01

    We retrospectively evaluated the anterior talo-fibular ligament and the tarsal sinus of 17 patients who had complained of chronic ankle external instability. This study based on both surgery and CT-arthrography findings shows the pathologic or normal aspects of the talo-fibular anterior ligament (normal, lax, fibrosis residue, ruptured). It confirms the good anatomic analysis of the tarsal sinus, i particular the anterior talo-calcaneal interosseous ligament and the search for fibrosis. We underline that capsular distension due to subtalar laxity is not detected with medical imaging. Compared with surgery (all patients), CT arthrography demonstrated the different aspects of the anterior talo fibular ligament injuries (normal, lax, discontinuous). (authors). 12 refs.

  18. Perpendicular magnetic anisotropy of Co85Cr15/Pt multilayers

    Institute of Scientific and Technical Information of China (English)

    Pol Hwang; Baohe Li; Tao Yang; Zhonghai Zhai; Fengwu Zhu

    2004-01-01

    The CoCr/Pt bilayers and (CoCr/Pt)20 multilayers with Pt underlayer were prepared by DC magnetron sputtering. The effects of prepared condition on perpendicular magnetic anisotropy were investigated. The results show that the thickness of Pt underlayer has a great effect on the microstructure and perpendicular magnetic anisotropy of CoCr/Pt bilayers and (CoCr/Pt)20 multilayers.When the thickness of Pt underlayer increases, Pt(111) and CoCr(002) peaks of both CoCr/Pt bilayers and (CoCr/Pt)20 multilayers increase and the bilayer periodicity of the multilayers is improved. The effective magnetic anisotropy of (CoCr/Pt)20 multilayers with Pt underlayer was much larger than that of CoCr/Pt bilayers. The (CoCr/Pt)20 multilayers has a stronger perpendicular magnetic anisotropy than that of CoCr/Pt bilayers. This is ascribed to the interface magnetic anisotropy of the multilayers.

  19. Contribution of MRI and CT arthrography to the diagnosis of intra-articular tendinopathy of the long head of the biceps.

    Science.gov (United States)

    Nourissat, G; Tribot-Laspiere, Q; Aim, F; Radier, C

    2014-12-01

    Clinical diagnosis of biceps tendinopathy is difficult to make because of the poor sensitivity of existing clinical tests. The goal of this study was to determine whether MRI or CT arthrogram could contribute to the diagnosis of tendinopathy in the intra-articular portion of the long head of biceps (LHB), while using macroscopic findings during shoulder arthroscopy as a reference. A prospective, single-centre study was performed over a 4-month period. The radiology part of the study was carried out by a radiologist experienced in shoulder imaging. The arthroscopy part of the study was conducted while the biceps was being evaluated for treatment purposes. The study included 87 patients having an average age of 45.7 years (range 17-78). Fifty-eight patients underwent CT arthrography and 38 underwent an MRI. Seven patients underwent both imaging exams. One patient was removed from the study because of a spontaneous LHB rupture. The demographics of the two study populations were equivalent. For the diagnosis of tendinopathy of the intra-articular portion of the long head of biceps, the CT arthrogram had a sensitivity of 71.43%, specificity of 100%, positive predictive value of 100% but a negative predictive value of 67.74%. For the diagnosis of tendinopathy of the intra-articular portion of the long head of biceps, the MRI had a sensitivity of 42.85%, specificity of 75%, positive predictive value of 50% but a negative predictive value of 69.23%. This study showed that radiological diagnosis of tendinopathy of the long head of biceps remains challenging. Nevertheless, CT arthrography is more sensitive and specific than MRI in identifying this disorder. III (case-control study). Copyright © 2014 Elsevier Masson SAS. All rights reserved.

  20. PT AND PT/NI "NEEDLE" ELETROCATALYSTS ON CARBON NANOTUBES WITH HIGH ACTIVITY FOR THE ORR

    Energy Technology Data Exchange (ETDEWEB)

    Colon-Mercado, H.

    2011-11-10

    Platinum and platinum/nickel alloy electrocatalysts supported on graphitized (gCNT) or nitrogen doped carbon nanotubes (nCNT) are prepared and characterized. Pt deposition onto carbon nanotubes results in Pt 'needle' formations that are 3.5 nm in diameter and {approx}100 nm in length. Subsequent Ni deposition and heat treatment results in PtNi 'needles' with an increased diameter. All Pt and Pt/Ni materials were tested as electrocatalysts for the oxygen reduction reaction (ORR). The Pt and Pt/Ni catalysts showed excellent performance for the ORR, with the heat treated PtNi/gCNT (1.06 mA/cm{sup 2}) and PtNi/nCNT (0.664 mA/cm{sup 2}) showing the highest activity.

  1. Indirect MR arthrography of anterior shoulder instability in the ABER and the apprehension test positions: a prospective comparative study of two different shoulder positions during MRI using intravenous gadodiamide contrast for enhancement of the joint fluid

    Energy Technology Data Exchange (ETDEWEB)

    Wintzell, G.; Larsson, S. [Uppsala University Hospital (Sweden). Dept. of Orthopaedics; Larsson, H. [Nacka-Soeder Hospital, Stockholm (Sweden). Dept. of Radiology

    1998-09-01

    The value of MRI for the evaluation of anterior shoulder instability can be enhanced by shoulder positions that stress the stabilising structures. The ABER position is one that has been described in combination with intra-articular gadopentetate dimeglumine arthrography. We believe that MRI in the Apprehension test position with 90 abduction and maximal tolerable external rotation provides maximum tension on the anterior stabilising structures and with this technique it is sufficient to use indirect gadodiamide arthrography following intravenous injection of the contrast medium. The purpose of this study was to make a prospective comparative evaluation of the ABER and Apprehension test positions when using indirect arthrography with intravenous gadodiamide administration in shoulders with anterior instability. Results. Both the ABER and the Apprehension test position were useful techniques in detecting capsulolabral pathology and Hill-Sachs lesions. The Apprehension test position produced significantly better gadodiamide-enhanced joint fluid in the region of pathology in both the capsulolabral lesion and the Hill-Sachs lesion. It also visualised the size of the Hill-Sachs lesion significantly better than did the ABER position. (orig.)

  2. Laser weldability of Pt and Ti alloys

    Energy Technology Data Exchange (ETDEWEB)

    Noolu, N.J. [Center for Advanced Materials Joining, University of Waterloo, Waterloo (Canada)]. E-mail: nnoolu@mecheng1.uwaterloo.ca; Kerr, H.W. [Center for Advanced Materials Joining, University of Waterloo, Waterloo (Canada); Zhou, Y. [Center for Advanced Materials Joining, University of Waterloo, Waterloo (Canada); Xie, J. [Cardiac Rhythm Management Division, Street Jude Medical Inc., Sylmar, CA (United States)

    2005-04-25

    Crack susceptibility of laser spot welds between Pt and Ti alloys was studied by characterizing the surface and the cross-sections of the welds produced at different pulse energies. Increase in laser pulse energy increased the dilution by the Ti alloy, giving rise to the evolution of microstructures with varying Ti contents across the entire fusion zone. Hardness results showed that regions with 66-75% Ti, i.e. consisting of primary Ti{sub 3}Pt and/or Ti{sub 3}Pt + TiPt eutectic, have a hardness higher than 700 Vickers hardness numbers (VHN), while regions with 42-66% Ti, i.e. consisting of primary TiPt, possessed hardness between 400 and 700 VHN. The extent of cracking increased with the increase in pulse energy and the cracked regions consisted of Ti contents between 50 and 75%. Brittle cracking in microstructures consisting of Ti{sub 3}Pt and TiPt phases suggested that one or both of the constituent phases are susceptible to cracking. However, crack arrest in microstructures predominantly consisting of TiPt showed that Ti{sub 3}Pt is the most susceptible phase to cracking in Pt-Ti alloy welds.

  3. Scattering properties of PT- symmetric layered periodic structures

    Science.gov (United States)

    Shramkova, O. V.; Tsironis, G. P.

    2016-10-01

    The optical properties of PT-symmetric periodic stacks of the layers with balanced loss and gain are examined. We demonstrate that the tunnelling phenomenon in periodic structures is connected with excitation of surface waves at the boundaries separating gain and loss regions within each unit cell and tunnelling conditions for periodic stacks can be reduced to the conditions for one period. Alternatively, it is shown that coherent perfect absorber laser states are mediated by excitation of surface modes localised at all internal boundaries of the structure. The effects of structure parameters, angles, direction of incidence on the resonant phenomena and spontaneous symmetry breaking transition are determined. It is shown that structural periodicity significantly increases the number of resonant phenomena, especially in stacks with high real and imaginary parts of dielectric permittivity of the layers.

  4. Low Pt content direct methanol fuel cell anode catalyst: nanophase PtRuNiZr

    Science.gov (United States)

    Narayanan, Sekharipuram R. (Inventor); Whitacre, Jay F. (Inventor)

    2010-01-01

    A method for the preparation of a metallic material having catalytic activity that includes synthesizing a material composition comprising a metal content with a lower Pt content than a binary alloy containing Pt but that displays at least a comparable catalytic activity on a per mole Pt basis as the binary alloy containing Pt; and evaluating a representative sample of the material composition to ensure that the material composition displays a property of at least a comparable catalytic activity on a per mole Pt basis as a representative binary alloy containing Pt. Furthermore, metallic compositions are disclosed that possess substantial resistance to corrosive acids.

  5. Direct Determination of the Ionization Energies of PtC, PtO, and PtO2 with VUVRadiation

    Energy Technology Data Exchange (ETDEWEB)

    Citir, Murat; Metz, Ricardo B.; Belau, Leonid; Ahmed, Musahid

    2008-07-21

    Photoionization efficiency curves were measured for gas-phase PtC, PtO, and PtO2 using tunable vacuum ultraviolet (VUV) radiation at the Advanced Light Source. The molecules were prepared by laser ablation of a platinum tube, followed by reaction with CH4 or N2O and supersonic expansion. These measurements providethe first directly measured ionization energy for PtC, IE(PtC) = 9.45 +- 0.05 eV. The direct measurement also gives greatly improved ionization energies for the platinum oxides, IE(PtO) = 10.0 +- 0.1 eV and IE(PtO2) = 11.35 +- 0.05 eV. The ionization energy connects the dissociation energies of the neutral and cation, leading to greatly improved 0 K bond dissociation energies for the neutrals: D0(Pt-C) = 5.95 +- 0.07 eV, D0(Pt-O)= 4.30 +- 0.12 eV, and D0(OPt-O) = 4.41 +- 0.13 eV, as well as enthalpies of formation for the gas-phase molecules Delta H0 f,0(PtC(g)) = 701 +- 7 kJ/mol, Delta H0f,0(PtO(g)) = 396 +- 12 kJ/mol, and Delta H0f,0(PtO2(g)) = 218 +- 11 kJ/mol. Much of the error in previous Knudsen cell measurements of platinum oxide bond dissociation energies is due to the use of thermodynamic second law extrapolations. Third law values calculated using statistical mechanical thermodynamic functions are in much better agreement with values obtained from ionization energies and ion energetics. These experiments demonstrate that laser ablation production with direct VUV ionization measurements is a versatile tool to measure ionization energies and bond dissociation energies for catalytically interesting species such as metal oxides and carbides.

  6. Comparative study of ethanol oxidation at Pt: Based nanoalloys and UPD modified Pt nanoparticles

    Directory of Open Access Journals (Sweden)

    Tripković Amalija V.

    2010-01-01

    Full Text Available The activity of two alloys, Pt3Sn/C and Pt3Ru2/C, was compared with the activity of Pt/C modified with corresponding amounts of SnUPD (≈25 % and RuUPD (≈40 % in oxidation of ethanol. Pt3Sn/C, Pt3Ru2/C and Pt/C catalysts were characterized by XRD. To establish the activity and stability of the catalysts, potentiodynamic, quasi steady-state and chronoamperometric measurements were performed. Both alloys are more active than SnUPD or RuUPD modified Pt/C catalysts. Electronic effect determining dominantly the activity of Pt3Sn/C is the main reason for its higher activity compared to Pt3Ru2/C. Since SnUPD and RuUPD do not provoke any significant modification of electronic environment, both modified Pt/C catalysts are less active than corresponding alloys. More pronounced difference in activity between Pt3Sn/C and SnUPD modified Pt/C than between Pt3Ru2/C and RuUPD modified Pt/C is caused by electronic effect in Pt3Sn/C. High activity of Pt3Sn/C modified with small amount of SnUPD (≈10% can be explained by combining the electronic effect, causing less strongly bonded adsorbate on Pt sites and easier mobility of SnUPD, with enhanced amount of oxygen-containing species on Sn sites resulting finally in reinforcement of bifunctional mechanism.

  7. Electrodeposited Pt and Pt-Sn nanoparticles on Ti as anodes for direct methanol fuel cells

    Institute of Scientific and Technical Information of China (English)

    Hanaa B HASSAN

    2009-01-01

    Electro-oxidation of methanol was studied on titanium supported nanocrystallite Pt and Ptx-Sny catalysts prepared by electrodeposition techniques. Their electro-catalytic activities were studied in 0.5mol/L H2SO4 and compared to those of a smooth Pt, Pt/Pt and Pt-Sn/Pt electrodes. Platinum was deposited on Ti by galvanostatic and potentiostatic techniques. X-ray diffractometer (XRD) and energy dispersive X-ray (EDX) techniques were applied in order to investigate the chemical composition and the phase structure of the modified electrodes. Scanning electron microscopy (SEM) was used to characterize the surface morphology and to correlate the results obtained from the two electrochemical deposition methods. Results show that modified Pt/Ti electrodes prepared by the two methods have comparable performance and enhanced catalytic activity towards methanol electro-oxidation compared to Pt/Pt and smooth Pt electrodes. Steady state Tafel plots experiments show a higher rate of methanol oxidation on a Pt/Ti catalyst than that on a smooth Pt. Introduction of a small amount of Sn deposited with Pt improves the catalytic activity and the stability of prepared electrode with time as indicated from the cyclic votlammetry and the chronoamperometric experiments. The effect of variations in the composition for binary catalysts of the type Ptx-Sny/Ti towards the methanol oxidation reaction is reported. Consequently, the Ptx-Sny/Ti (x∶y (8∶1), molar ratio) catalyst is a very promising one for methanol oxidation.

  8. Optomechanical magnetometry with a macroscopic resonator

    CERN Document Server

    Yu, Changqiu; Sheridan, Eoin; McAuslan, David L; Rubinsztein-Dunlop, Halina; Lam, Ping Koy; Zhang, Yundong; Bowen, Warwick P

    2015-01-01

    We demonstrate a centimeter-scale optomechanical magnetometer based on a crystalline whispering gallery mode resonator. The large size of the resonator allows high magnetic field sensitivity to be achieved in the hertz to kilohertz frequency range. A peak sensitivity of 131 pT per root Hz is reported, in a magnetically unshielded non-cryogenic environment and using optical power levels beneath 100 microWatt. Femtotesla range sensitivity may be possible in future devices with further optimization of laser noise and the physical structure of the resonator, allowing applications in high-performance magnetometry.

  9. Magnetic susceptibility and hardness of Au-xPt-yNb alloys for biomedical applications.

    Science.gov (United States)

    Uyama, Emi; Inui, Shihoko; Hamada, Kenichi; Honda, Eiichi; Asaoka, Kenzo

    2013-09-01

    Metal devices in the human body induce serious metal artifacts in magnetic resonance imaging (MRI). Metals artifacts are mainly caused by a volume magnetic susceptibility (χv) mismatch between a metal device and human tissue. In this research, Au-xPt-yNb alloys were developed for fabricating MRI artifact-free biomedical metal devices. The magnetic properties, hardness and phase constitutions of these alloys were investigated. The Au-xPt-8Nb alloys showed satisfactory χv values. Heat treatments did not clearly change the χv values for Au-xPt-8Nb alloys. The Vickers hardness (HV) of these two alloys was much higher than that of high-Pt alloys; moreover, aging at 700°C increased the HV values of these two alloys. A dual phase structure consisting of face-centered cubic α1 and α2 phases was observed and aging at 700°C promoted phase separation. The Au-5Pt-8Nb and Au-10Pt-8Nb alloys showed satisfactory χv values and high hardness and are thus suggested as candidates for MRI artifact-free alloys for biomedical applications.

  10. High-performance core-shell PdPt@Pt/C catalysts via decorating PdPt alloy cores with Pt

    Science.gov (United States)

    Wu, Yan-Ni; Liao, Shi-Jun; Liang, Zhen-Xing; Yang, Li-Jun; Wang, Rong-Fang

    A core-shell structured low-Pt catalyst, PdPt@Pt/C, with high performance towards both methanol anodic oxidation and oxygen cathodic reduction, as well as in a single hydrogen/air fuel cell, is prepared by a novel two-step colloidal approach. For the anodic oxidation of methanol, the catalyst shows three times higher activity than commercial Tanaka 50 wt% Pt/C catalyst; furthermore, the ratio of forward current I f to backward current I b is high up to 1.04, whereas for general platinum catalysts the ratio is only ca. 0.70, indicating that this PdPt@Pt/C catalyst has high activity towards methanol anodic oxidation and good tolerance to the intermediates of methanol oxidation. The catalyst is characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM), and X-ray photoelectron spectroscopy (XPS). The core-shell structure of the catalyst is revealed by XRD and TEM, and is also supported by underpotential deposition of hydrogen (UPDH). The high performance of the PdPt@Pt/C catalyst may make it a promising and competitive low-Pt catalyst for hydrogen fueled polymer electrolyte membrane fuel cell (PEMFC) or direct methanol fuel cell (DMFC) applications.

  11. $\\mathcal{PT}$-symmetric mode-locking

    CERN Document Server

    Longhi, Stefano

    2016-01-01

    Parity-time ($\\mathcal{PT}$) symmetry is one of the most important accomplishments in optics over the past decade. Here the concept of $\\mathcal{PT}$ mode-locking of a laser is introduced, in which active phase locking of cavity axial modes is realized by asymmetric mode coupling in a complex time crystal. $\\mathcal{PT}$ mode-locking shows a transition from single to double pulse emission as the $\\mathcal{PT}$ symmetry breaking point is crossed. The transition can show a turbulent behavior, depending on a dimensionless modulation parameter that plays the same role as the Reynolds number in hydrodynamic flows.

  12. In-plane anisotropic effect of magnetoelectric coupled PMN-PT/FePt multiferroic heterostructure: Static and microwave properties

    Directory of Open Access Journals (Sweden)

    Jose M. Vargas

    2014-10-01

    Full Text Available The effects of the electric and magnetic field variation on multiferroic heterostructure were studied in this work. Thin films of polycrystalline Fe50Pt50 (FePt were grown by dc-sputtering on top of the commercial slabs of lead magnesium niobate-lead titanate (PMN-PT. The sample was a (011-cut single crystal and had one side polished. In this condition, the PMN-PT/FePt operates in the L-T (longitudinal magnetized-transverse polarized mode. A FePt thin film of 20 nm was used in this study to avoid the characteristic broad microwave absorption line associated with these films above thicknesses of 40 nm. For the in-plane easy magnetization axis (01-1, a microwave magnetoelectric (ME coupling of 28 Oe cm kV −1 was estimated, whereas a value of 42 Oe cm kV −1 was obtained through the hard magnetization axis (100. Insight into the effects of the in-plane strain anisotropy on the ME coupling is obtained from the dc-magnetization loops. It was observed that the trend was opposite along the easy and hard magnetic directions. In particular, along the easy-magnetic axis (01-1, a square and narrow loop with a factor of Mr/MS of 0.96 was measured at 10 kV/cm. Along the hard-magnetic axis, a factor of 0.16 at 10 kV/cm was obtained. Using electric tuning via microwave absorption at X-band (9.78 GHz, we observe completely different trends along the easy and hard magnetic directions; Multiple absorption lines along the latter axis compared to a single and narrower absorption line along the former. In spite of its intrinsic complexity, we propose a model which gives good agreement both for static and microwave properties. These observations are of fundamental interest for future ME microwave components, such as filters, phase-shifters, and resonators.

  13. Remarks on the PT-pseudo-norm in PT-symmetric quantum mechanics

    Energy Technology Data Exchange (ETDEWEB)

    Duc Tai Trinh [Department of Mathematics, Teacher Training College of Dalat, 29 Yersin, Dalat (Viet Nam)]|[Abdus Salam International Centre for Theoretical Physics, Strada Costiera 11, Trieste 34014 (Italy)

    2005-04-22

    This paper presents an underlying analytical relationship between the PT-pseudo-norm associated with the PT-symmetric Hamiltonian H = p{sup 2} + V(q) and the Stokes multiplier of the differential equation corresponding to this Hamiltonian. We show that the sign alternation of the PT-pseudo-norm, which has been observed as a generic feature of the PT-inner product, is essentially controlled by the derivative of a Stokes multiplier with respect to the eigenparameter.

  14. Rotator cuff tears: should abduction and external rotation (ABER) positioning be performed before image acquisition? A CT arthrography study

    Energy Technology Data Exchange (ETDEWEB)

    Cochet, Hubert [Hopital Cardiologique du Haut-Leveque, CHU Bordeaux, Unite d' Imagerie Thoracique et Cardiovasculaire, Pessac (France); Couderc, Stephane; Pele, Eric; Moreau-Durieux, Marie-Helene; Hauger, Olivier [Hopital Pellegrin, CHU Bordeaux, Unite d' Imagerie Osteo-articulaire, Bordeaux (France); Amoretti, Nicolas [CHU Archet, Unite d' Imagerie Osteo-articulaire, Nice (France)

    2010-05-15

    To evaluate the impact of abduction and external rotation (ABER) positioning performed before image acquisition on the assessment of rotator cuff tears. Twenty-seven consecutive patients with clinically suspected rotator cuff tears underwent an initial CT arthrogram of the shoulder in neutral position, immediately followed by temporary ABER positioning, before a second CT acquisition in neutral position. Two observers blinded to potential pre-procedure ABER positioning independently analysed the randomly distributed images. Lesions were classified into partial-thickness (PT) and full-thickness (FT) tear subtypes. Lesion detection and measurements of pre- and post-ABER studies were compared. We found no influence of pre-test ABER positioning on FT detection or measurements. Every PT detected on pre-ABER study was also detected on post-ABER study (28/28 for reader 1, and 32/32 for reader 2). Seven and eight additional PT were found by readers 1 and 2, respectively, on post-ABER study. Lesion size increased after ABER in terms of area (P < 0.001 for both readers) and Ellman's grade (P = 0.02 and 0.002 for reader 1 and 2, respectively). ABER positioning before CT is associated with improved delineation of partial tears, a higher number of detected tears and modification of treatment planning. (orig.)

  15. Room-temperature formation of Pt$_3$Si/Pt$_2$Si films on poly-Si substrates

    CERN Document Server

    Dubkov, V P; Chizh, K V; Yuryev, V A

    2016-01-01

    We propose a way of formation of thin bilayer Pt$_3$Si/Pt$_2$Si films at room temperature on poly-Si substrates by Pt magnetron sputtering and wet etching, obtain such film, investigate its structure and phase composition and estimate the thickness of its layers. We verify by direct x-ray photoelectron-spectroscopic measurements our previous observation of the Pt$_2$Si layer formaton between Pt and poly-Si films as a result of Pt magnetron sputtering at room temperature. This layer likely appears due to high enough temperature of Pt ions in the magnetron plasma sufficient for chemical reaction of the silicide film formation on the Si surface. The Pt$_3$Si layer likely forms from the Pt--Pt$_3$Si layer (Pt$_{95}$Si$_5$), which arises under Pt film during the magnetron sputtering, as a result of Pt removal by wet etching.

  16. A comparative study of Pt and Pt-Pd core-shell nanocatalysts

    Energy Technology Data Exchange (ETDEWEB)

    Long, Nguyen Viet, E-mail: nguyenviet_long@yahoo.com [Department of Materials Science and Engineering, Nagoya Institute of Technology, Gokiso-cho, Showa-ku, Nagoya 466-8555 (Japan); Posts and Telecommunications Institute of Technology, km 10 Nguyen Trai, Thanh Xuan, Ha Dong, Hanoi (Viet Nam); Laboratory for Nanotechnology, Vietnam National University, Ho Chi Minh, Linh Trung, Thu Duc, Ho Chi Minh (Viet Nam); Department of Molecular and Material Sciences, Interdisciplinary Graduate School of Engineering Sciences, Kyushu University, 6-1 Kasugakouen, Kasuga, Fukuoka 816-8580 (Japan); Ohtaki, Michitaka [Department of Molecular and Material Sciences, Interdisciplinary Graduate School of Engineering Sciences, Kyushu University, 6-1 Kasugakouen, Kasuga, Fukuoka 816-8580 (Japan); Hien, Tong Duy [Laboratory for Nanotechnology, Vietnam National University, Ho Chi Minh, Linh Trung, Thu Duc, Ho Chi Minh (Viet Nam); Randy, Jalem [Department of Materials Science and Engineering, Nagoya Institute of Technology, Gokiso-cho, Showa-ku, Nagoya 466-8555 (Japan); Nogami, Masayuki, E-mail: nogami@nitech.ac.jp [Department of Materials Science and Engineering, Nagoya Institute of Technology, Gokiso-cho, Showa-ku, Nagoya 466-8555 (Japan)

    2011-10-30

    Highlights: > The syntheses of Pt (4-8 nm) and Pt-Pd core-shell nanoparticles (15-25 nm) are showed. > Pt-Pd core-shell catalysts possess catalytic property much better than Pt catalysts. > Pt-Pd core-shell catalysts exhibit fast and highly stable catalytic activity. > Fascinatingly, size effect is not as really important as nanostructuring effect. > Fast, stable, sensitive hydrogen adsorption is very crucial for fuel cells. - Abstract: This comparative study characterizes two types of metallic and core-shell bimetallic nanoparticles prepared with our modified polyol method. These nanoparticles consist of Pt and Pt-Pd core-shell nanocatalysts exhibiting polyhedral morphologies. The controlled syntheses of Pt metallic nanoparticles in the 10-nm regime (4-8 nm) and Pt-Pd bimetallic core-shell nanoparticles in the 30-nm regime (15-25 nm) are presented. To realize our ultimate research goals for proton exchange membrane fuel cells (PEMFCs) and direct methanol fuel cells (DMFCs), we thoroughly investigate the dependence of the electrocatalytic properties of the nanoparticles on the structure, size and morphology. Significant differences in the electrocatalysis are also explained in experimental evidences of both Pt and Pt-Pd nanocatalysts. We suggested that the core-shell controlled morphologies and nanostructures of the Pd nanoshell as the Pd atomic monolayers will not only play an important role in producing inexpensive, novel Pt- and Pd-based nanocatalysts but also in designing more efficient Pt- and Pd-based nanocatalysts for practical use in DMFC technology. Our comparative results show that Pt-Pd nanocatalysts with Pd nanoshells exhibited much better electrocatalytic activity and stabilization compared to Pt nanocatalysts. Interestingly, we found that the size effect is not as strong as the nanostructuring effect on the catalytic properties of the researched nanoparticles. A nanostructure effect of the core-shell bimetallic nanoparticles was identified.

  17. AN ANIMAL MODEL OF PLATINUM (PT) HYPERSENSITIVITY

    Science.gov (United States)

    Exposure to Pt salts has been associated with occupational asthma. Pt, the most active component and widely used metal in catalytic converters, is released in automobile exhaust and is a proposed diesel fuel additive. Thus, with the potential for widespread environmental distrib...

  18. Metrology with PT-Symmetric Cavities: Enhanced Sensitivity near the PT-Phase Transition.

    Science.gov (United States)

    Liu, Zhong-Peng; Zhang, Jing; Özdemir, Şahin Kaya; Peng, Bo; Jing, Hui; Lü, Xin-You; Li, Chun-Wen; Yang, Lan; Nori, Franco; Liu, Yu-Xi

    2016-09-09

    We propose and analyze a new approach based on parity-time (PT) symmetric microcavities with balanced gain and loss to enhance the performance of cavity-assisted metrology. We identify the conditions under which PT-symmetric microcavities allow us to improve sensitivity beyond what is achievable in loss-only systems. We discuss the application of PT-symmetric microcavities to the detection of mechanical motion, and show that the sensitivity is significantly enhanced near the transition point from unbroken- to broken-PT regimes. Our results open a new direction for PT-symmetric physical systems and it may find use in ultrahigh precision metrology and sensing.

  19. Photothermal resonance

    DEFF Research Database (Denmark)

    2014-01-01

    The present invention relates to a method for detecting photo-thermal absorbance of a material utilising a mechanically temperature sensitive resonator (20) and a sample being arrange in thermal communication with the temperature sensitive resonator. The present invention further relates to an ap......The present invention relates to a method for detecting photo-thermal absorbance of a material utilising a mechanically temperature sensitive resonator (20) and a sample being arrange in thermal communication with the temperature sensitive resonator. The present invention further relates...... to an apparatus for detecting photo-thermal absorbance of a sample....

  20. Bolometric detection of ferromagnetic resonance in YIG slab

    Science.gov (United States)

    Tu, Sa; Białek, Marcin; Zhang, Youguang; Zhao, Weisheng; Yu, Haiming; Ansermet, Jean-Philippe

    2017-10-01

    The resistance of the Pt bar deposited on the YIG slab was monitored while the magnetic field was ramped through the ferromagnetic resonance with the YIG slab facing a coplanar waveguide resonator excited at 4.3 GHz excitation. The resistance change provides detection of the ferromagnetic resonance with a high signal-to-noise ratio. It is ascribed to a change in the temperature of the Pt bars. The thermal origin of the signal is confirmed by the observation that the signal vanishes when field modulation is applied at frequencies above 6 Hz. The spin pumping effect was vanishingly small, and the anisotropic magnetoresistance of the Pt bar, though quite easily observed, would imply a rectification voltage that is much smaller than the bolometric effect.