Diagnostic value of MRI in meniscus injury. Comparison of MRI and arthrography

International Nuclear Information System (INIS)

Iso, Yoshinori; Nozaki, Hiroyuki; Emoto, Mari; Miyairi, Taro; Hirata, Aya; Hirasawa, Seiichi; Suguro, Toru; Igata, Atsuomi; Kudo, Yukihiko.

1995-01-01

Magnetic resonance imaging (MRI) and arthrography were performed on 90 knees to compare the diagnostic value for meniscus injury with these techniques. The diagnostic accuracy of MRI and arthrography was 89.1% and 87.1%, respectively. Imaging of the medial meniscus was somewhat better with arthrography, and delineation of the lateral meniscus was somewhat better with MRI. MRI was superior in diagnoses of horizontal and degenerative lacerations, but showed the shape of the injuries less clearly than arthrography. The diagnostic accuracy of MRI decreased with the age of the patients and was inferior to arthrography for patients in their forties or older. In conclusion, MRI is a less invasive approach with high diagnostic accuracy for meniscus injury and is a promising substitute for arthrography. (author)

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.

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

International Nuclear Information System (INIS)

Yoo, Koun J.; Ha, Doo Hoe; Lee, Sang Min

2011-01-01

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.

Direct magnetic resonance arthrography of the canine elbow

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Yauheni Zhalniarovich

2017-01-01

Full Text Available This study compares the effects of four dilutions of the gadolinium-containing contrast media (1:100; 1:400; 1:800; 1:1,200 administered to the elbow on the quality of magnetic resonance images. All the examined dilutions had a positive effect on image quality, and 1:800 was regarded as the optimal dilution of gadolinium for viewing the elbow because it imparted good contrast to the joint cavity without obliterating the contours of articular surfaces. Transverse, sagittal, and dorsal low-field magnetic resonance images were obtained in 24 canine cadaver front limbs. The musculus biceps brachii, m. triceps brachii, m. extensor carpi radialis, m. flexor carpi ulnaris, the articular surfaces, the medial coronoid process and the anconeal process of the ulna were well visualized by High Resolution Gradient Echo, XBONE T2 and Spin Echo T1 sequences in the sagittal plane. The biceps brachii, pronator teres, flexor carpi radialis, extensor digitorum communis, extensor carpi radialis, deltoid muscle and the articular surface of the medial condyle of the humerus were very well visualized by 3D SST1 and XBONE T2 sequences in the transverse plane. The triceps brachii muscle, extensor digitorum lateralis muscle, superficial digital flexor, deep digital flexor and the medial condyle of the humerus were very well visualized by the Spin Echo T1 sequence in the dorsal plane. This article describes for the first time the use of the gadolinium contrast agent administered to the canine elbow joint during magnetic resonance modality. Magnetic resonance arthrography can be a helpful visualization technique in treating canine soft tissue elbow injury.

MR-guided direct arthrography of the glenohumeral joint

International Nuclear Information System (INIS)

Soh, E.; Bearcroft, P.W.P.; Graves, M.J.; Black, R.; Lomas, D.J.

2008-01-01

Aim: To evaluate the feasibility of magnetic resonance (MR)-guided direct arthrography of the glenohumeral joint with a 1.5 T MR system, performing the entire procedure in a single MR examination. Materials and methods: MR-guided direct arthrography was performed on 11 patients. MR imaging guidance and interactive MR fluoroscopy, with in-room control and display system, were used for needle placement and contrast medium injection. The outcome measures were success or failure of joint puncture, the time taken for introduction of contrast medium, and the diagnostic quality of the subsequent MR arthrography images. Results: Contrast medium was successfully instilled into the joint and diagnostic quality MR arthrography images were obtained in all cases. The median time from initial placement of the skin marker to introduction of the contrast medium was 17 min (range 11-29 min). There were no immediate post-procedure complications. Conclusion: Accurate needle placement is feasible in a single MR examination on a commercial 1.5 T closed-bore MR system, using an in-room control and display system together with interactive fluoroscopic imaging, and this was used to provide direct MR arthrography in this study

A comparison of MRI and wrist arthrography in the diagnosis of TFC injury

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Shionoya, Kaori; Nakamura, Ryogo; Imaeda, Toshihiko [Nagoya Univ., Aichi (Japan). Branch Hospital; Tsunoda, Kenji; Makino, Naoki

1995-08-01

The present study compared the diagnostic usefulness of magnetic resonance imaging (MRI) and wrist arthrography in triangular fibrocartilage (TFC) injuries. The subjects were 102 wrists with arthroscopically confirmed presence or absence of TFC perforation. TFC perforation was present in 35 and 47 wrists and absent in the other 67 and 55 wrists on arthrography and MRI, respectively. Using arthroscopy as the reference standard, arthrography for the detection of TFC perforation had a sensitivity of 85% and a specificity of 100%. All 6 false negative cases on arthrography had scarring adhesions of the TFC in the wrist. On the other hand, the sensitivity and specificity of MRI were 73% and 72%, respectively. An accuracy was 94% for arthrography and 73% for MRI. It was difficult to detect qualitative TFC injury and the presence or absence of TFC perforation on MRI. Arthrography is thus superior to MRI in both sensitivity and specificity. The complementary use of arthrography and MRI is considered to increase the diagnostic accuracy. (S.Y.).

Temporomandibular joint arthrography: normal anatomy and technique of examination

International Nuclear Information System (INIS)

Duvoisin, B.; Schnyder, P.; Klaus, E.; Jacques, B.

1990-01-01

Temporomandibular joint (TMJ) dysfunction is common. This entity is most often consecutive to internal derangements of the TMJ, which are not recognizable on plain films and tomograms. TMJ arthrography has proved a valuable tool in diagnosing these abnormalities. The technique of examination and normal arthrographic anatomy are reviewed. (author) [pt

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

International Nuclear Information System (INIS)

Ahn, Sang Hyuk; Park, Jung Hwan; Moon, Tae Yong; Lee, In Sook; Lee, Seung Jun

2012-01-01

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

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.

Arthrography

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Full Text Available ... large film sheets (much like a large photographic negative). Today, most images are digital files that are ... limitations of arthrography? The limitations of arthrography include: Partial tears of the rotator cuff may not be ...

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- ... of arthrography? The limitations of arthrography include: Partial tears of the rotator cuff may not be detected ...

Arthrography

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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 ...

Arthrography

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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 ...

Cartilage lesions in the ankle joint: comparison of MR arthrography and CT arthrography

International Nuclear Information System (INIS)

Schmid, M.R.; Pfirrmann, C.W.A.; Hodler, J.; Zanetti, M.; Vienne, P.

2003-01-01

To compare MR arthrography and CT arthrography for the evaluation of cartilage lesions in the ankle joint.Design and patients Thirty-six consecutive patients with clinically suspected cartilage lesions were prospectively included in the study. A 1:1 mixture of diluted gadoteridol (4 mmol/l) and iopamidol (300 mg iodine/ml) was injected. The articular cartilages of the talus, tibia, and fibula were analyzed separately by two musculoskeletal radiologists. A review panel consisting of two musculoskeletal radiologists and an orthopedic surgeon represented the standard of reference. For reader 1 accuracy of MR arthrography in the talus/tibia/fibula (88%/88%/94%) was slightly inferior to CT arthrography (90%/94%/92%). For reader 2, the accuracy was 76%/78%/83% for MR arthrography, and 92%/93%/92% for CT arthrography, respectively. Interobserver agreement for MR arthrography was 79%/74%/89% (kappa 0.47/0.34/0.27), while interobserver agreement for CT arthrography was 89%/90%/89% (kappa 0.69/0.54/0.54). CT arthrography appears to be more reliable than MR arthrography for the detection of cartilage lesions in the ankle joint. (orig.)

Clinical arthrography

International Nuclear Information System (INIS)

Arndt, R.; Horns, J.W.; Gold, R.H.; Blaschke, D.D.

1985-01-01

This book deals with the method and interpretation of arthrography of the shoulder, knee, ankle, elbow, hip, wrist, and metacarpophalangeal, interphalangeal, and temporomandibular joints. The emphasis is on orthopaedic disorders, usually of traumatic origin, which is in keeping with the application of arthrography in clinical practice. Other conditions, such as inflammatory and degenerative diseases, congenital disorders and, in the case of the hip, arthrography of reconstructive joint surgery, are included. Each chapter is devoted to one joint and provides a comprehensive discussion on the method of arthrography, including single and double contrast techniques where applicable, normal radiographic anatomy, and finally, the interpretation of the normal and the abnormal arthrogram

Knee arthrography today

International Nuclear Information System (INIS)

Otto, H.; Kallenberger, R.

1987-01-01

The role of knee arthrography today is demonstrated and technical problems are discussed. Among a lot of variants the position of the patient and the choice of contrast media play a great part concerning the result of the examination. Mild complications occur in 0.25% of the examinations, severe and live threatening complications are extremely rare. Diagnosis of meniscal lesions is most important for knee arthrography; arthroscopy and arthrography are complementary examinations and not mutually exclusive, they achieve combined an accuracy of 97-98%. In the same way arthrography is able to evaluate the condropathy of the femoro-tibial joint, whereas accuracy of arthroscopy in the diagnosis of patellar chondropathy is much higher. There is a great reliability of arthrography regarding the evaluation of lesions of the capsule, but accuracy in lesions of the cruciate ligaments is low. Arthrography is very suitable for evaluation of Baker-cysts, since indications for almost occuring internal derangement of the knee are even available. Knee arthrography is a complex and safe procedure with very less discomfort for the patient; it has a central position in the evaluation of lesions of the knee. (orig.) [de

MR arthrography of the knee

International Nuclear Information System (INIS)

Kramer, J.; Engel, A. Jr.; Stiglbauer, R. Jr.; Prayer, L. Jr.; Hajek, P. Jr.; Imhof, H.

1991-01-01

This paper demonstrates the diagnostic value of MR arthrography in the assessment of cartilaginous lesions, including osteochondritis dissecans. One hundred thirty-two knees of 125 patients were examined with MR arthrography performed on a 1.5-T magnet with a knee resonator. T1-weighted spin-echo and T2*-weighted three-dimensional gradient-echo sequences were obtained after intraarticular administration of 40 mL of 2-mmol GD-DTPA solution. Seventy-five patients were also imaged without contrast agent. The description of the articular surface was classified into four types: I, normal cartilage surface and thickness; II, surface normal or slightly irregular; III, severe surface irregularities and cartilage defects; and IV, extensive cartilage defects, scar formation. MR findings were correlated with those of arthroscopy/arthrotomy (n = 75)

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

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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

CT-guided puncture for direct MR-arthrography of the shoulder: Description of possible techniques

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Hauth E

2016-07-01

Full Text Available The following report describes the possible techniques of CT-guided puncture for direct magnetic resonance (MR arthrography of the shoulder. CT-guided puncture can be regarded as an alternative technique to fluoroscopic- or ultrasound-guided puncture for MR-arthrography of the shoulder with high efficiency, low dose and extremely low complication rate.

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.

Shoulder instability syndrome: comparison of CT, arthrography and MR findings

International Nuclear Information System (INIS)

Ortiz, L.; Alcaraz, M.; Preciados, J.L.G.; Garcia Alvarez, A.; Castello, J.

1995-01-01

Currently, the two most reliable explorations for diagnosing the lesions that produce shoulder instability are computerized tomography with arthrography and magnetic resonance following intraarticular injection of gadolinium. Dynamic CT arthrography is considered the best method to assess these lesions; MR is a similar procedure but involves certain drawbacks, among them, its cost. The techniques applied in these explorations are reviewed, as are the anatomy of the different components of this joint and the radiological findings leading to a diagnosis of the pathology underlying its instability. (Author)

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

Science.gov (United States)

Pahwa, Shivani; Srivastava, Deep N; Sharma, Raju; Gamanagatti, Shivanand; Kotwal, Prakash P; Sharma, Vijay

2014-01-01

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. PMID:25114389

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

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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.

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

International Nuclear Information System (INIS)

Ferrari, Francesco S.; Governi, Simone; Burresi, Francesca; Vigni, Francesco; Stefani, Paolo

2002-01-01

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.)

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

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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.)

Diagnostic Accuracy and Inter-Observer Agreement of Shoulder Magnetic Resonance Arthrography in the Detection of Labral Lesion and Assessment of Lesion Location

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Hwang, Ji Young; Song, Sook Yun; Choi, Jin Ha; Shin, Sang Jin [School of Medicine, Ewha Womans University, Mokdong Hospital, Seoul (Korea, Republic of)

2012-11-15

To evaluate the diagnostic accuracy and inter-observer agreement of magnetic resonance (MR) arthrography in the detection of labral lesions by location and to describe useful MR imaging findings of labral tears. Sixty-eight patients who underwent both pre-operative MR arthrography and arthroscopy were included. The location of the labrum was classified into anterior (2-6 o'clock), superior (12-2 o'clock), and posterior (6-12 o'clock). Sensitivity, specificity, accuracy, and inter-observer agreement of MR arthrography for the diagnosis of labral lesions by location were calculated. Frequency of MR imaging findings such as detachment, high signal intensity cleft, contour change, absence, and signal change of the labrum by location were analyzed. 35 anterior, 44 superior and 15 posterior labral lesions were detected by arthroscopy. The corresponding sensitivities were 91.4%, 79.5%, and 40.0%, specificities were 90.9%, 20.8%, and 86.8%, accuracies were 91.2%, 58.8%, and 76.5%, and kappa values were 0.823, 0.252, and 0.394, for anterior, superior, posterior lesions, respectively. The most common MR imaging findings were detachment in 60.0% of anterior labrums, high signal intensity cleft in 52.3% of superior labrums, and normal in 60.0% of posterior labrums. Diagnostic accuracy and inter-observer agreement of MR arthrography in the diagnosis of labral lesions are high in anterior labrums and low in superior or posterior labrums. The useful MR imaging findings of labral tears were different according to labral location.

MRI and arthrography in the evaluation of TMJ disorders

International Nuclear Information System (INIS)

Nakasato, Tatsuhiko; Ehara, Shigeru; Tamakawa, Yoshiharu; Kobayakawa, Takafumi.

1991-01-01

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)

MRI and arthrography in the evaluation of TMJ disorders

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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).

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

International Nuclear Information System (INIS)

Amin, Mohammed Farghally; Youssef, Ahmed Omar

2012-01-01

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

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

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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.

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

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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.)

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

International Nuclear Information System (INIS)

Schreinemachers, Saskia A.; Hulst, Victor P.M. van der; Woude, Henk-Jan van der; Willems, W.J.; Bipat, Shandra

2009-01-01

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.)

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.)

Imaging diagnostics of the wrist: MRI and Arthrography/Arthro-CT; Bildgebende Diagnostik des Handgelenkes: MRT und Arthrographie/Arthro-CT

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Klein, H.M.; Balas, R.; Neugebauer, F. [Radiologische Gemeinschaftspraxis, Betzdorf (Germany); Vrsalovic, V. [Handchirugie, Marienhospital Siegen, Siegen (Germany)

2002-02-01

Purpose: To evaluate the use of magnetic resonance imaging (MRI) compared with arthrography and arthro-CT (AG/ACT) in patients with wrist pain. Methods: MRI and arthrography/arthro-CT (AG/ACT) of the wrist joint were retrospectively evaluated in 346 patients over a three-year period. Imaging findings were correlated to surgical results (n=78) or clinical course in an at least 6-month follow-up. Results: For tears of the triangular fibrocartilage, arthrography, arthro-CT, and MRI demonstrated a sensitivity and specificity of more than 0.96. Only the positive predictive value was superior for arthrography/arthro-CT (0.99 and 0.98, respectively) compared with MRI (0.94). Arthrography was superior for functional diagnosis of scapho-lunate ligament tears (n=25). Ulno-lunate and ulno-triquetral ligament defects were demonstrated more exactly by arthrography. Traumatic osseous defects, particularly scaphoid fractures (n=33) and avascular necrosis (n=17), were better diagnosed using MRI. Conclusion: For suspected lesions of the triangular fibrocartilage complex, AG/ACT is slightly more reliable than MRI. However, MRI was found to be highly accurate in diagnosing TFC tears, and is superior to AG/ACT in detecting traumatic and vascular lesions of the wrist. (orig.) [German] Ziel: Die Untersuchung der diagnostischen Aussagekraft von Magnetresonanz-Tomographie (MRT), Arthrographie (AG) und Arthro-CT (ACT) bei Erkrankungen des Handgelenkes. Methodik: Insgesamt 346 Untersuchungen des Handgelenkes wurden fuer einen dreijaehrigen Beobachtungszeitraum retrospektiv ausgewertet. Es wurden 211 MRT, 151 Arthrographien (AG) und 126 Arthro-CT (ACT) durchgefuehrt. Alle Diagnosen wurden operativ (n=78) oder durch den klinischen Verlauf in einer 6-monatigen Nachbeobachtung gesichert. Ergebnisse: Fuer die Diagnostik von Laesionen des diskoulnaren Komplexes lag die Sensitivitaet und Spezifitaet von AG, ACT und MRT ueber 0,96. Lediglich der positive Vorhersagewert differierte, allerdings nicht

Value and limits of knee arthrography

International Nuclear Information System (INIS)

Fischedick, O.

1981-01-01

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. (orig.) [de

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

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

International Nuclear Information System (INIS)

Jung, Joon-Yong; Jee, Won-Hee; Chun, Ho Jong; Ahn, Myeong Im; Kim, Yang-Soo

2010-01-01

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 κ 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 κ=0.55 to κ=0.68. Likewise, intraobserver agreements increased from κ=0.79 and 0.53 to κ=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 tendon

The diagnostic accuracy of acetabular labral tears using magnetic resonance imaging and magnetic resonance arthrography: a meta-analysis

Energy Technology Data Exchange (ETDEWEB)

Smith, Toby O. [University of East Anglia, Faculty of Health, Queen' s Building, Norwich (United Kingdom); Hilton, Gemma [Norfolk and Norwich University Hospital, Norwich (United Kingdom); Toms, Andoni P.; Donell, Simon T. [Norfolk and Norwich University Hospital, University of East Anglia, Norwich (United Kingdom); Hing, Caroline B. [St. George' s Hospital, London (United Kingdom)

2011-04-15

Magnetic resonance imaging (MRI) and magnetic resonance arthrography (MRA) have been advocated for the diagnosis of acetabular labral tears. The purpose of this study was to determine the sensitivity and specificity of MRI and MRA in diagnosing acetabular labral tears using meta-analysis. Pertinent published and unpublished literature databases were reviewed. A two-by-two table was constructed to calculate the sensitivity and specificity of MRI or MRA investigations against surgical outcomes. Pooled sensitivity and specificity and Receiver Operating Characteristic curve (ROC) evaluations were performed. Methodological quality of each study was assessed using the QUADAS (Quality Assessment of Diagnostic Accuracy Studies) tool. Nineteen papers assessing 881 hips were reviewed. Conventional MRI was assessed in 13 studies and MRA was assessed in 16 studies. Whilst both MRI (0.5-3T) and MRA (0.5-3T) presented with a moderate sensitivity and specificity (sensitivity 66%, 87%; specificity 79%, 64%), diagnostic accuracy of MRA appeared to be superior to MRI in detecting acetabular labral tears on ROC curve interpretation. The literature poorly described population characteristics, assessor blinding, with limited sample sizes. MRI and MRA may be useful adjuncts in the diagnosis of acetabular labral tears in adults. MRA appears to be superior to conventional MRI. (orig.)

Prospective, double-blind comparison of shoulder MR imaging, US, arthrography, and arthroscopy

International Nuclear Information System (INIS)

Resendes, M.; Drace, J.E.; Pyka, W.

1988-01-01

To determine the efficacy of diagnostic imaging modalities in the evaluation of shoulder pain, magnetic resonance (MR) imaging, ultrasonography (US) and arthrography were prospectively compared in a double-blind experimental protocol. Thirty consecutive patients were studied by these modalities, which received separate, blinded interpretations. The images and interpretations were sealed in an envelope and blinded from the arthroscopist for initial arthroscopy, but second-look arthroscopy, and in some cases open surgery, was performed after the envelopes were unsealed. To avoid selection bias, negative MR and/or US examinations never affected confirmation by arthrography and/or arthroscopy, so negatives and positives were equivalently tested. To date, MR imaging and US are equally sensitive in the detection of rotator cuff tears, but the combination is more sensitive. Both MR imaging and US demonstrated tears not diagnosed by means of arthrography, and MR imaging distinguished hemorrhagic muscle tears from rotator cuff tears, which arthrography and arthroscopy did not. Both MR imaging and US showed characteristic appearances of biceps tendonitis, but neither demonstrated adhesive capsulitis. The authors conclude that all three imaging modalities have a role in shoulder diagnosis

Arthrography of the equine shoulder joint

International Nuclear Information System (INIS)

Nixon, A.J.; Spencer, C.P.

1990-01-01

Techniques and normal radiographic anatomy for positive and double contrast shoulder arthrography in horses were evaluated. General anaesthesia was used for most radiographic projections of the shoulder. The mediolateral projection provided the most information during arthrography, although the supinated mediolateral view occasionally allowed better definition of the cartilage surfaces on the medial aspects of the humeral head. The craniocaudal mediolateral oblique and caudocranial projections provided limited additional information. Water soluble non-ionic contrast agents, such as metrizamide and iohexol, were suitable for shoulder arthrography; iohexol resulted in less synovitis and lameness. Arthrography in cases of osteochondrosis and osteochondritis dissecans allowed better evaluation of cartilage attachment to subchondral bone, better evaluation of the length and depth of cartilage lesions and more accurately defined the site and shape of osteocartilaginous free bodies. Cartilage thickening without detachment from the subchondral bone could only be determined by arthrography. Although these thick cartilage regions may later dissect from the subchondral bone, most cases where the cartilage was firmly adherent were not candidates for surgical debridement and carried a favourable prognosis. The determination of a free flap by arthrography indicated the need for surgery. Extensive humeral and glenoid cavity lesions were better defined by arthrography, allowing a rational decision between surgical debridement or euthanasia. Using arthrography, evaluation of the size and patency of the communicating canal to a subchondral cystic defect better separated cases with long, narrow and poorly patent canals for conservative rather than surgical therapy

Value of knee joint arthrography

International Nuclear Information System (INIS)

Luzsa, Gyoergy; Kiss Toth, Peter

1985-01-01

On the basis of the literature and the analysis of 204 examinations, the method and clinical application of knee joint arthrography are reviewed. 50 out of the 54 operated cases were perfectly diagnosed. The double contrast knee joint arthrography can be applied to detect meniscus changes, popliteal cysts, synovial disorders and chondral defects. The effectiveness of arthrography and arthroscopy was compared and the introduction of the former in each county seat is suggested. (author)

Comparison between 3D isotropic and 2D conventional MR arthrography for diagnosing rotator cuff tear and labral lesions: A meta-analysis.

Science.gov (United States)

Lee, Sun Hwa; Yun, Seong Jong; Jin, Wook; Park, So Young; Park, Ji Seon; Ryu, Kyung Nam

2018-03-30

lesions. 3D-isotropic MR arthrography can replace 2D-conventional MR arthrography. 3D-isotropic MR arthrography using TSE sequence is recommended for more accurate diagnosis, as it demonstrates increased sensitivity. 2 Technical Efficacy: Stage 3 J. Magn. Reson. Imaging 2018. © 2018 International Society for Magnetic Resonance in Medicine.

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.)

Ferromagnetic resonance characterization of nano-FePt by electron spin resonance

CSIR Research Space (South Africa)

Nkosi, SS

2013-01-01

Full Text Available Electron spin resonance (ESR) measurements at room temperature and X-band microwave frequency were performed on highly crystalline FePt system thin films. Fairly high DC static magnetic field absorption of about 300 mT was observed in these films...

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.)

Arthrography

Medline Plus

Full Text Available ... top of page How should I prepare? No special preparation is necessary before direct arthrography. Food and fluid intake do not need to be restricted, unless a sedative will be ...

Field-angle dependence of magnetic resonance in Pt/NiFe films

International Nuclear Information System (INIS)

Inoue, H.Y.; Harii, K.; Saitoh, E.

2007-01-01

Ferromagnetic resonance in NiFe/ amorphous Pt bilayer thin films was investigated with changing the external field direction. The spectral width of the ferromagnetic resonance depends critically on the external-magnetic-field direction. We found that the sample dependence of the spectral width is enhanced with deviation of external field direction from the direction along the film plain, implying an important role of spin directions in field-induced spin-decoherence mechanism in Pt

Arthrography

Medline Plus

Full Text Available ... the joint and appears on the MR images. As in conventional direct arthrography, the contrast material outlines the structures within the joint, such as cartilage, ligaments and bones, and allows them to ...

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

International Nuclear Information System (INIS)

Sahin, Guelden; Demirtas, Mehmet

2006-01-01

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

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

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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.

Arthrography

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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 ...

Arthrography

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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 ...

Arthrography

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Full Text Available ... a table on which the patient lies. The traditional MRI unit is a large cylinder-shaped tube ... MRI) - Shoulder X-ray, Interventional Radiology and Nuclear Medicine Radiation Safety Images related to Direct Arthrography Videos ...

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Full Text Available ... CT arthrography and have claustrophobia (fear of enclosed spaces) or anxiety, you may want to ask your ... and sometimes air are injected into the joint space while the radiologist observes with fluoroscopy or ultrasound. ...

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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 ...

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Full Text Available ... by the interpreting radiologist. Frequently, the differentiation of abnormal (diseased) tissue from normal tissues is better with ... Benefits Direct arthrography is particularly effective for detecting disease of the structures within the joints such as ...

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Full Text Available ... others nearby harm. These items include: jewelry, watches, credit cards and hearing aids, all of which can ... top of page What are the benefits vs. risks? Benefits Direct arthrography is particularly effective for detecting ...

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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 ...

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Full Text Available ... have MR or CT arthrography and have claustrophobia (fear of enclosed spaces) or anxiety, you may want ... physician and technologist if they may be pregnant. Children younger than 13 may need to be sedated ...

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Full Text Available ... thus allowing for enhanced imaging of small internal structures. This leads to improved evaluation of diseases or ... conventional direct arthrography, the contrast material outlines the structures within the joint, such as cartilage, ligaments and ...

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Full Text Available ... and possibly hear gurgling when the joint is moved. If your arthrography exam involves MR imaging: It is normal for the area of your body being imaged to feel slightly warm, but if it ...

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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 ...

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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 ...

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Full Text Available ... of the body to a small dose of ionizing radiation to produce pictures of the inside of ... or copied to CD. MRI does not use ionizing radiation (x-rays). CT direct arthrography uses the ...

Arthrography of the ankle sprains

International Nuclear Information System (INIS)

Han, Moon Hee

1985-01-01

Ankle arthrography, by direct puncture of joint cavity, is considered to be a simple and accurate diagnostic method for a precise evaluation of ligamentous injury. Forty-seven cases of ankle arthrography were successively performed in the patients of acute ankle sprains. The purpose of this study is to demonstrate how ankle arthrography can delineate the pathologic anatomy in such cases. The results are as follows: 1. Thirty cases among forty seven revealed the findings of ligament tears. 2. For better diagnostic accuracy, the arthrography should be performed within 72 hrs. after injury. 3. The anterior talofibular ligament tears were the most common (twenty-nine cases) of all and seventeen of them revealed tears without association of any other ligament tears. 4. There were ten cases of calcaneofibular ligament tears and nine of them were associated with anterior talofibular ligament tears. 5. Three cases of anterior tibiofibular and one deltoid ligament tears were demonstrated

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.

Arthrography

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

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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

Arthrography

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Full Text Available ... of the body to a small dose of ionizing radiation to produce pictures of the inside of the ... or copied to CD. MRI does not use ionizing radiation (x-rays). CT direct arthrography uses the same ...

Diagnosis of SLAP lesions with Grashey-view arthrography

International Nuclear Information System (INIS)

Lee, J.H. Edmund; Van Raalte, Vanessa; Malian, Vartan

2003-01-01

To examine the accuracy of Grashey views obtained during shoulder arthrography in the diagnosis of clinically relevant superior labrum anterior-posterior (SLAP) lesions. Grashey views obtained during diagnostic arthrography (conventional and MR) were used to examine the superior labrum. Twenty-eight of 118 shoulder arthrograms obtained during a 27-month period fulfilled study criteria and were correlated for accuracy using arthroscopically confirmed grade 2-4 SLAP lesions as the standard of reference. Arthrograms were graded using the consensus method. Prevalence, sensitivity, specificity, and accuracy were 21%, 50%, 86%, and 79%. The appearance of the superior labrum on the Grashey view was compared subjectively with MR arthrography. Sources of errors were analyzed. Grashey views obtained during shoulder arthrography can diagnose clinically relevant SLAP lesions with moderately high specificity, moderate accuracy, and limited sensitivity. Findings on the Grashey view closely resemble those seen on coronal oblique MR arthrography. Grashey views should be considered in patients undergoing shoulder arthrography. (orig.)

Diagnosis of SLAP lesions with Grashey-view arthrography

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Lee, J.H. Edmund [Radiological Associates of Sacramento Medical Group, Inc., 1500 Expo Parkway, Sacramento, CA 95815 (United States); Department of Diagnostic Radiology, UC Davis Medical Center, 4860 Y Street, Suite 3100, Sacramento, CA 95817 (United States); Van Raalte, Vanessa; Malian, Vartan [Department of Diagnostic Radiology, UC Davis Medical Center, 4860 Y Street, Suite 3100, Sacramento, CA 95817 (United States)

2003-07-01

To examine the accuracy of Grashey views obtained during shoulder arthrography in the diagnosis of clinically relevant superior labrum anterior-posterior (SLAP) lesions. Grashey views obtained during diagnostic arthrography (conventional and MR) were used to examine the superior labrum. Twenty-eight of 118 shoulder arthrograms obtained during a 27-month period fulfilled study criteria and were correlated for accuracy using arthroscopically confirmed grade 2-4 SLAP lesions as the standard of reference. Arthrograms were graded using the consensus method. Prevalence, sensitivity, specificity, and accuracy were 21%, 50%, 86%, and 79%. The appearance of the superior labrum on the Grashey view was compared subjectively with MR arthrography. Sources of errors were analyzed. Grashey views obtained during shoulder arthrography can diagnose clinically relevant SLAP lesions with moderately high specificity, moderate accuracy, and limited sensitivity. Findings on the Grashey view closely resemble those seen on coronal oblique MR arthrography. Grashey views should be considered in patients undergoing shoulder arthrography. (orig.)

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Full Text Available ... copied to CD. MRI does not use ionizing radiation (x-rays). CT direct arthrography uses the same type ... remains in a patient's body after an x-ray examination. X-rays usually have no side effects in the ...

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Full Text Available ... your procedure. top of page What does the equipment look like? The equipment typically used for this examination consists of a ... in a separate room from the scanner. Other equipment necessary for performing arthrography include a variety of ...

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Full Text Available ... to Direct Arthrography Sponsored by Please note RadiologyInfo.org is not a medical facility. Please contact your ... links: For the convenience of our users, RadiologyInfo .org provides links to relevant websites. RadiologyInfo.org , ACR ...

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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. ...

MR arthrography of the ankle joint

International Nuclear Information System (INIS)

Trattnig, S.; Rand, T.; Breitenseher, M.; Ba-Ssalamah, A.; Schick, S.; Imhof, H.

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.) [de

Arthrography

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Full Text Available ... may help your physician determine the cause of chronic joint pain and what therapies may be effective. ... Benefits Direct arthrography is particularly effective for detecting disease ... Any procedure where the skin is penetrated carries a risk of infection. The ...

T2[sup *] weighted MR imaging for the diagnosis of the perforation of triangular fibrocartilage; Comparison with arthrography

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Nakamura, Taro; Nakamura, Eiziro; Ahsoh, Kuniichi; Masumi, Shogo (Oita Medical Univ., Takatsuki (Japan))

1994-05-01

Perforation of the triangular fibrocartilage (TFC) has been considered an important factor in the etiology of pain in the ulnar wrist joint, and arthrography has been used conventionally to diagnose the perforation. Recently, magnetic resonance imaging (MRI) has been used to diagnose TFC perforation. Gundy et al. examined cadaver wrists with Tl weighted imaging and arthrography, and obtained findings suggesting that arthrography provides a more accurate diagnosis of the TFC perforation. To our knowledge, no comparison has yet been made between T2[sup *] weighted imaging and arthrography in the diagnosis of TFC perforation. The present study compared the usefulness of T2[sup *]-weighted imaging and arthrography in the diagnosis of TFC perforation in 22 wrist joints of 11 cadavers (5 males and 6 females with ages ranging from 61 to 92 years and an average age of 78.8 years) fixed in 60% formalin. The specimens were firstly analyzed by a T2[sup *]-weighted 0.5T MRI scan and subsequently by arthrography. After diagnosing the image obtained by the two methods, the accuracy of the diagnosis was determined by comparison with the macroscopic findings of autopsy, including the presence and degree of TFC perforation. A T2[sup *]-weighted MRI scan of the TFC perforation showed high-intensity areas over the distal radio-ulnar joint, and demonstrated the same diagnostic accuracy as arthrography, providing correct diagnoses in all cases other than linear perforation. However, neither of the image diagnostic methods allowed definition of the type of perforation. (author).

The preliminary application of magnetic resonance arthrography in the diagnosis of acetabular labrale tears

International Nuclear Information System (INIS)

Hong Wen; Zhang Xuezhe; Wang Wu; Yue Debo; Wang Weiguo

2010-01-01

Objective: To investigate the application value of MR arthrography (MRA) in the diagnosis of acetabular lab ral tears. Methods: Fifteen patients with a high degree of suspected acetabular lab ral tears received fluoroscope-guided injection of the contrast media into the hip joint (hip arthrography) and fat-saturated spin-echo T 1 -weighted images were obtained in the coronal, sagittal, oblique-axial and radial planes. Hip arthroscopy was performed on 12 of them. Results: Lab ral tears which were diagnosed in 11 patients by hip MRA were confirmed at hip arthroscopy. One patient showed no MRA indication of lab ral tear, also showed normal on arthroscopy. Tear in the anterior-superior quadrant 10 cases of 12 joints (12/13), posterior-superior quadrant 1 case of a joint (1/13). In 11 patients who underwent arthroscopy, hip MRA diagnosed 3 (3/13) joints labrale tears in coronal planes, 10 (10/13) joints in sagittal planes and 13 (13/13) labrale tears in axial-oblique and radial planes. In 15 patients with 20 hip joints, 5 cases 6 joints (6/20) with normal acetabular sublabral sulcus were performed. Conclusions: MR arthrography of hip is a reliable method in the diagnosis of acetabular labrale tears. Scanning method should be included fat-saturated spin-echo T 1 -weighted images in sagittal and oblique-axial planes or sagittal plus radial planes. The diagnosis of torn posterior-inferior quadrant should pay attention to the existence of a normal variation. (authors)

Arthrography

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Full Text Available ... be asked to wear a gown. What is Direct Arthrography? What are some common uses of the procedure? How should I prepare? What does the equipment look like? How does the procedure work? How is the procedure performed? What will I ...

Anterior labral tear: diagnostic value of MR arthrography of the shoulder

International Nuclear Information System (INIS)

Ryu, Jung Kyu; Yoon, Yeong Cheol; Ryu, Kyung Nam; Rhee, Yong Girl

2001-01-01

To assess the accuracy of magnetic resonance(MR) arthrography in the diagnosis of anterior labral tear of the shoulder Between september 1996 and February 2000, MR arthrography of the shoulder was performed in 281 patients with a history of shoulder pain or instability. Among this total, only 157 shoulders in 154 patients who underwent arthroscopy or open surgery 0 to 230 (average, 20.9) days after MR arthrography were included in this study; the subjects comprised of 150 males and 4 females with an average age of 23.3 years. MR arthrographs of these 154 patients were analyzed for the presence of anterior labral tears, and the findings were correlated with the arthroscopic and surgical findings. Anterior labral tear was classified as A to D according to its location, as determined by arthroscopy and surgery. (A=4 to 6 o'clock direction, anteroinferior; B=2 to 4 o'clock direction, central; C=12 to 2 o'clock direction, anterosuperior; D= SLAP lesion). The retrospective analysis of MR arthrographs showing false-positive and negative findings was also underthken.. In the diagnosis of anterior labral tear, MR arthrography showed a sensitivity of 94%, a specificity of 90% and an accuracy of 91%. Anterior labral tears were confirmed by arthroscopy or surgery in 62 of the 157 shoulders (39%). Among 62 lesion, two (3%) were observed in area A, 32(52%) in area A+B, nine (15%) in area A+B+C, one(2%) in area A+B+D,13(21%) in area A+B+C+D, two (3%) in area B+C, one(2%) in area B+D, and two(3%) in area C. Among ten false-positive cases, seven were focal lessions (two, three and two lesions in area A, B and C, respectively), and in the remaining three cases, lacated in area A+B, MR arthrography revealed thickening and deformation. All four false negatives were focal lesions (two in area A and two in area C). Other than in focal lesions, in which accuracy was relatively low, MR arthrography showed high sensitivity, specificity and accuracy in the diagnosis of anterior labral tear

Anterior approach for knee arthrography

International Nuclear Information System (INIS)

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

2001-01-01

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

Arthrography

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Full Text Available ... have very controlled x-ray beams and dose control methods to minimize stray (scatter) radiation. This ensures that those parts of a patient's body not being imaged receive minimal radiation exposure. top of page What are the limitations of arthrography? The limitations of ...

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 How should I prepare? No special preparation is necessary before direct arthrography. Food and fluid intake do not need to be restricted, unless a sedative will be ...

Ankle ligamints : comparison of MR arthrography with conventional MR imaging in amputated feet

International Nuclear Information System (INIS)

Yoo, Jae Sung; Lee, Sang Yong; Lee, Jeong Min; Han, Young Min; Chung, Kyung Ho; Kim, CHong Soo

2001-01-01

To compare magnetic resonance (MR) arthrography with conventional MR imaging in the evaluation of ankle ligaments. Eight freshly amputated human feet underwent conventional MR imaging and MR arthrography. For the former, 1.5-T magnets in the axial, coronal and sagittal planes were used, and T1-weighted sequences were obtained. Following the injection of 6-10 ml of diluted contrast media (Gd-DTPA 1:250), T1-weighted images were obtained in the same positions as conventional MR images. Paired conventional MR imaging and MR arthrography of each ankle ligament were rated on a five-point scale, and to reflect inter-group differences a Wilcoxon singed-rank test was used to compare the different measurements (p<0.05). In two ankles, MR images of the ligaments were correlated with ankle dissection. Anterior and posterior talofibular ligaments were more clearly revealed by MR arthrography than by conventional MR imaging, while calcaneofibular ligaments showed no difference between these two modalities. With regard to deltoid ligaments, visualization of the anterior and posterior tibiotalar ligament was much improved when contrast material was used to outline the ligament's articular aspect. Visualization of the posterior inferior tibiofibular ligament and inferior transverse ligament were also improved when the use of contrast material provided delineation of the articular side of the ligaments and separated them from adjacent bone. In addition, MR arthography was very useful for indentification of the posterior intermalleolar ligament, though its use did not enhance visualization of the calcaneofibular, tibiocalcaneal, spring or tibiospring ligaments. MR arthrography accurately revealed the anatomic details of ankle ligaments, and may therefore be more useful than conventional Mr imaging for evaluation of these structures

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

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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.)

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

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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.

Arthrography of the ankle

International Nuclear Information System (INIS)

Lindholmer, E.; Foged, N.; Jensen, J. Th.

1978-01-01

Arthrography was performed in 105 cases with freshly sprained ankles and signs of rupture of the anterior talofibular ligament. They were subsequently operated upon. The arthrographic films were examined retrospectively to assess the value of different criteria for the differential diagnosis between rupture of the anterior talofibular ligament and combined rupture of this and the calcaneofibular ligament. The diagnostic value of arthrography was found to be high in isolated rupture of the anterior talofibular ligament, and is acceptable in the combined ruptures. (Auth.)

Arthrography of the ankle joint

International Nuclear Information System (INIS)

Crespi Porro, R.; Zellner, A.; Puricelli, G.; Quaglia, R.; Chelazzi, G.

1984-01-01

Arthrography of the ankle joint was first carried out by Johnson and Palmer at the Military Hospital in Stockholm in 1940. Arthrography can be used for judging the integrity of the articular cartilage, of osteochondritis dissecans, arthritis or adhesive capsulitis. The literature shows, however, that more than 95% of the patients on whom this examination has been performed has suffered from acute trauma. (orig.) [de

A PMMA coated PMN–PT single crystal resonator for sensing chemical agents

International Nuclear Information System (INIS)

Frank, Michael; Kassegne, Sam; Moon, Kee S

2010-01-01

A highly sensitive lead magnesium niobate–lead titanate (PMN–PT) single crystal resonator coated with a thin film of polymethylmethacrylate (PMMA) useful for detecting chemical agents such as acetone, methanol, and isopropyl alcohol is presented. Swelling of the cured PMMA polymer layer in the presence of acetone, methanol, and isopropyl alcohol vapors is sensed as a mass change transduced to an electrical signal by the PMN–PT thickness shear mode sensor. Frequency change in the PMN–PT sensor is demonstrated to vary according to the concentration of the chemical vapor present within the sensing chamber. For acetone, the results indicate a frequency change more than 6000 times greater than that which would be expected from a quartz crystal microbalance coated with PMMA. This study is the first of its kind to demonstrate vapor loading of adsorbed chemical agents onto a polymer coated PMN–PT resonator

Arthrography

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Full Text Available ... processes the imaging information is located in a separate room from the scanner. Other equipment necessary for performing arthrography include a variety of needles, syringes and a water-soluble contrast material. top of page How does the procedure work? X-rays are a form of radiation like ...

Arthrography

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Full Text Available ... The images can then be examined on a computer monitor connected to an image archive (PACS system) or printed or copied to CD. MRI does not use ionizing radiation (x-rays). CT direct arthrography uses the same type of ... by a computer using x-rays. top of page What are ...

Multidetector spiral CT arthrography of the shoulder

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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.

Multidetector spiral CT arthrography of the shoulder

International Nuclear Information System (INIS)

Lecouvet, Frederic E.; Simoni, Paolo; Koutaissoff, Sophie; Vande Berg, Bruno C.; Malghem, Jacques; Dubuc, Jean-Emile

2008-01-01

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

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

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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).

Detection and staging of chondromalacia patellae: relative efficacies of conventional MR imaging, MR arthrography, and CT arthrography.

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Gagliardi, J A; Chung, E M; Chandnani, V P; Kesling, K L; Christensen, K P; Null, R N; Radvany, M G; Hansen, M F

1994-09-01

Chondromalacia patellae is a condition characterized by softening, fraying, and ulceration of patellar articular cartilage. We compare the sensitivity, specificity, and accuracy of conventional MR imaging, MR arthrography, and CT arthrography in detecting and staging this abnormality. Twenty-seven patients with pain in the anterior part of the knee were prospectively examined with MR imaging, including T1-weighted (650/16), proton density-weighted (2000/20), T2-weighted (2000/80), and spoiled two-dimensional gradient-recalled acquisition in the steady state (SPGR/)/35 degrees (51/10) with fat saturation pulse sequences. All were also examined with T1-weighted MR imaging after intraarticular injection of dilute gadopentetate dimeglumine and with double-contrast CT arthrography. Each imaging technique was evaluated independently by two observers, who reached a consensus interpretation. The signal characteristics of cartilage on MR images and contour abnormalities noted with all imaging techniques were evaluated and graded according to a modification of the classification of Shahriaree. Twenty-six of the 54 facets examined had chondromalacia shown by arthroscopy, which was used as the standard of reference. The sensitivity, specificity, and accuracy of each imaging technique in the diagnosis of each stage of chondromalacia patellae were determined and compared by using the McNemar two-tailed analysis. Arthroscopy showed that 28 facets were normal. Grade 1 chondromalacia patellae was diagnosed only with MR and CT arthrography in two (29%) of seven facets. Intermediate (grade 2 or 3) chondromalacia patellae was detected in two (13%) of 15 facets with T1-weighted and SPGR MR imaging, in three (20%) of 15 facets with proton density-weighted MR imaging, in seven (47%) of 15 facets with T2-weighted MR imaging, in 11 (73%) of 15 facets with CT arthrography, and in 12 (80%) of 15 facets with MR arthrography. Grade 4 was detected in three (75%) of four facets with T1-, proton

A study on usefulness of CT arthrography for the temporomandibular joint

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Murakami, Shumei [Osaka Univ. (Japan). School of Dentistry

1992-06-01

In the field of orthopedics, CT arthrography has been utilized for the shoulder and the knee joints diagnosis. In this study, CT arthrography was applied to the temporomandibular joint (TMJ) and the usefulness of this method was evaluated experimentally and clinically. In the experimental study, CT, CT arthrography and arthrotomogtaphy were compared each other with serial section from human autopsy specimen. It was confirmed that arthrography was indispensable for diagnosis of the location and configuration of the articular disk. In the sagittal section, CT arthrography was almost equal to arthrotomography. But in the coronal section, CT arthrography proved to be advantageous to arthrotomography, because there were various blur images on the arthrotomographic images from the complex bony structures of the skull. In the clinical study, coronal CT arthrography was applied for the patients with internal derangements of the TMJ. The mesio-lateral displacement of the disk (62%), perforation of the attachment (23%), and the intra-articular adhesion (70%) could be diagnosed. BY CT arthrography, the mesio-lateral displacement of the disk was more clearly diagnosed and the intra-articular adhesions were proved with higher rate than by the arthrotomography. From this study, it was concluded that CT arthrography has an important role in diagnosis of the TMJ soft tissue. (author) 51 refs.

Wrist arthrography

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Fransson, S.G. (Dept. of Diagnostic Radiology, University Hospital, Linkoeping (Sweden))

1993-03-01

The ligaments of the proximal row of carpal bones and the triangular fibrocartilage (TFC) strongly influence the function and stability of the wrist. Injury to the ligaments may result in chronic wrist pain or instability. Wrist arthrography is valuable in the investigation of such damage when surgical intervention is considered and plain radiography is unrewarding. There are also several technical modifications of the standard radiocarpal arthrography available. Owing to the possibility of congential perforations and degenerative changes in these ligaments the arthrographic findings should be related to the clinical signs and the age of the patient. CT has less diagnostic importance in this respect while MR imaging is an alternative and may become the method of choice. Both these methods have great potential in the evaluation of soft tissues of the wrist other than the TFC. (orig.).

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

International Nuclear Information System (INIS)

Shortt, Conor P.; Morrison, William B.; Deely, Diane M.; Gopez, Angela G.; Zoga, Adam C.; Roberts, Catherine C.

2009-01-01

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.)

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

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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.)

Shoulder distention arthrography as a treatment modality

International Nuclear Information System (INIS)

Kang, Heung Sik; Park, Chan Sup; Kim, Jin Ho; Kim, Sang Bum

1987-01-01

18 patients with painful stiff shoulder joint were underwent shoulder distension arthrography as a treatment modality, followed by physical therapy. Range of motion of shoulder joint was evaluated at 1 week and 4 weeks after arthrography. The results were as follows; 1. Arthrographic findings were decreased volume of joint cavity, obliteration of axillary recess, small subscapularis bursa, serrated capsular margin and non-filling of biceps tendon sheath. In 3 cases, rotator cuff tear was found. 2. Range of motion of shoulder joint was improved after distension arthrography. 3. In 3 patients have rotator cuff tear, range of motion was not improved

Combined nuclear and digital subtraction contrast arthrography in painful knee prosthesis

International Nuclear Information System (INIS)

Namasivayam, J.; Forrester, A.; Poon, F.W.; Cuthbert, G.F.; McKillop, J.H.; Bryan, A.S.

1992-01-01

The evaluation of a painful knee prosthesis remains a difficult problem for both orthopaedic surgeons and radiologists. We have compared digital subtraction arthrography with nuclear-arthrography in 7 patients with a painful knee prosthesis. Three patients showed a loose tibial component, demonstrated by both digital subtraction and nuclear arthrography. All 3 underwent revision of their prosthesis. One patient had an equivocal digital subtraction arthrogram and negative nuclear arthrogram, while both studies were negative in the 3 remaining patients. Nuclear arthrography is a simple procedure and can provide useful additional information when combined with digital subtraction arthrography. (orig.)

Wrist ligament injuries: value of post-arthrography computed tomography

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Theumann, N.; Schnyder, P.; Meuli, R. [Dept. of Diagnostic and Interventional Radiology, University Hospital, CHUV, Lausanne (Switzerland); Favarger, N. [Clinique Longeraie, Lausanne (Switzerland)

2001-02-01

Objective: To evaluate the use of post-arthrography high-resolution computed tomography in wrist ligament injuries.Design and patients: Thirty-six consecutive patients who had a history and clinical findings suggestive of ligamentous injuries of the wrist were prospectively studied. The findings of three-compartment arthrography and post-arthrography computed tomography (arthro-CT) were compared with those of arthroscopy. The evaluation concentrates on the detection and precise localization of ligament lesions in the triangular fibrocartilage (TFC), the scapholunate ligament (SLL) and the lunotriquetral ligament (LTL).Results: For TFC, SLL and LTL lesions, standard arthrography responded with a sensitivity and specificity of 85% and 100%, 85% and 100%, 80% and 100% respectively, while arthro-CT showed a sensitivity and specificity of 85% and 100%, 100% and 100%, 80% and 100% respectively. The precise localization of the lesions was possible only with arthro-CT.Conclusion: The sensitivity and specificity of standard arthrography and arthro-CT are similar, although the latter shows the site of tears or perforation with greater precision, while conventional arthrography demonstrates them indirectly. This precision is essential and may have clinical implications for the success of treatment procedures. (orig.)

The hamatolunate facet: characterization and association with cartilage lesions - magnetic resonance arthrography and anatomic correlation in cadaveric wrists

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Pfirrmann, C.W.A. [Department of Radiology, Veterans Administration Medical Center, 3350 La Jolla Village Dr., San Diego, CA 92161 (United States); Orthopedic University Hospital Balgrist, Department of Radiology, Forchstrasse 340, 8008 Zurich (Switzerland); Theumann, N.H.; Chung, C.B.; Trudell, D.J.; Resnick, D. [Department of Radiology, Veterans Administration Medical Center, 3350 La Jolla Village Dr., San Diego, CA 92161 (United States)

2002-08-01

The objective of this study was to characterize the appearance of the hamatolunate facet using high-resolution magnetic resonance (MR) arthrography in cadavers and to correlate the presence of this anatomic variant with the presence of osteoarthritis in the wrist. High-resolution MR images of 22 cadaveric wrist specimens were obtained after tri-compartmental arthrography. Two readers in consensus analyzed the MR images and recoded the presence or absence of a hamatolunate facet. Geometric characteristics and cartilage and ligament integrity were analyzed. A third reader, who was blinded to the purpose of the study, recorded cartilage lesions of all the bones of the proximal and distal carpal rows. A hamatolunate facet was present in 11 of 22 wrists (50%). The mean coronal size of the lunate facet at the lunate (type II lunate) was 4.5 mm (range, 2-6 mm). The highest frequencies of cartilage lesions were seen in the scapho-trapezio-trapezoid joint (45.5%) and at the proximal pole of the hamate (54.4% and 40.9% for consensus reading/blinded reading, respectively). In cases with a hamatolunate facet, the frequency of cartilage lesions in the proximal pole of the hamate was 81.8% and 63.6% versus 27.3% and 18.2% without such a facet (chi-squared, P=0.01/P=0.03). No correlation of the presence of a hamatolunate facet with interosseous ligament tears or lesions of the triangular fibrocartilage was seen. In conclusion, the hamatolunate facet is a very common anatomic variant. The presence of a hamatolunate facet is associated with cartilage damage in the proximal pole of the hamate. (orig.)

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

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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.

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.)

MR arthrography of the shoulder: possible indications for clinical use

International Nuclear Information System (INIS)

Kreitner, K.F.; Grebe, P.; Kersjes, W.; Runkel, M.; Kirschner, P.; Schild, H.H.

1994-01-01

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.) [de

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.)

Diagnostic performance of indirect MR arthrography for the diagnosis of rotator cuff tears at 3.0 T.

Science.gov (United States)

Lee, Ji Hyun; Yoon, Young Cheol; Jee, Sukkyung

2015-06-01

Indirect magnetic resonance (MR) arthrography is a non-invasive method for shoulder imaging. However, there are no studies that have examined the diagnostic performance of indirect MR arthrography for the diagnosis of rotator cuff tears in a large patient population. To assess the diagnostic performance of indirect fast spin-echo (FSE) MR arthrography for the diagnosis of rotator cuff tears at 3.0 T. A total of 149 patients who had undergone indirect shoulder MR arthrography followed by arthroscopic surgery were enrolled in this retrospective study. Two musculoskeletal radiologists evaluated images from each patient for the presence of supraspinatus-infraspinatus (SSP-ISP) or subscapularis (SSC) tendon tears. Using the arthroscopic findings as the reference standard, the overall diagnostic performance and detection rates for SSP-ISP and SSC tendon tears were calculated. The sensitivity, specificity, and accuracy of readers I and II for the diagnosis of SSP-ISP tendon tears were 94% and 95%, 89% and 85%, and 93% and 93%, respectively. The sensitivity of imaging for detection of SSP-ISP tendon tears by readers I and II were 100% and 100% for full-thickness tears and 84% and 86% for partial-thickness tears, respectively. The sensitivity, specificity, and accuracy of readers I and II for the diagnosis of SSC tendon tears were 80% and 76%, 89% and 93%, and 85% and 85%, respectively. Indirect MR arthrography is useful for the detection of SSP-ISP and SSC tendon tears. © The Foundation Acta Radiologica 2014 Reprints and permissions: sagepub.co.uk/journalsPermissions.nav.

Arthrography of the ankle joint in chronic instability

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Dory, M.A.

1986-05-01

Papers on arthrography of injuries of the lateral ligaments of the ankle relate mainly to recent distortion of the joint. Arthrography performed at a later stage after injury generally is considered useless. In fact, changes in chronic instability are observed; they are subtle and consist either of small recesses adjacent to the lateral malleolus or communication of the joint with the peroneal tendon sheaths. Arthrography was assessed in 61 cases of recurrent lateral sprains of the ankle more than 2 weeks after acute injury; 38 were considered as positive. Twenty-five patients had operative evaluation, with four false negative and one false positive results. Small recesses adjacent to the lateral malleolus or opacification of the peroneal tendon sheaths are sequelae of an acute sprain with tear of the anterior talofibular and/or the calcaneofibular ligaments. Although false negative results occur, arthrography is useful in the preoperative assessment of chronic ankle instability.

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.

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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.

Arthrography of the TMJ

International Nuclear Information System (INIS)

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

1986-01-01

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. (orig.) [de

C1-2 arthrography

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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.)

C1-2 arthrography

International Nuclear Information System (INIS)

Chevrot, A.; Cermakova, E.; Vallee, C.; Chancelier, M.D.; Chemla, N.; Rousselin, B.; Langer-Cherbit, A.

1995-01-01

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.)

Arthrography of the ankle joint in chronic instability

International Nuclear Information System (INIS)

Dory, M.A.

1986-01-01

Papers on arthrography of injuries of the lateral ligaments of the ankle relate mainly to recent distortion of the joint. Arthrography performed at a later stage after injury generally is considered useless. In fact, changes in chronic instability are observed; they are subtle and consist either of small recesses adjacent to the lateral malleolus or communication of the joint with the peroneal tendon sheaths. Arthrography was assessed in 61 cases of recurrent lateral sprains of the ankle more than 2 weeks after acute injury; 38 were considered as positive. Twenty-five patients had operative evaluation, with four false negative and one false positive results. Small recesses adjacent to the lateral malleolus or opacification of the peroneal tendon sheaths are sequelae of an acute sprain with tear of the anterior talofibular and/or the calcaneofibular ligaments. Although false negative results occur, arthrography is useful in the preoperative assessment of chronic ankle instability. (orig.)

Optical characterization of broad plasmon resonances of Pd/Pt nanoparticles

Science.gov (United States)

Valizade-Shahmirzadi, N.; Pakizeh, T.

2018-04-01

In this paper, optical properties of nanoparticles (nanodisks and nanospheres) composed of photofunctional metals like palladium (Pd) and platinum (Pt) over a large dimension range are investigated using the electromagnetic simulation and quasi-static theory. These characteristics are compared with their counterparts in plasmonic gold (Au) nanoparticles. Pd/Pt-nanodisks with larger dimension have higher absorption and lower scattering efficiencies than Au-nanodisks that accompany with lower extinction efficiencies and broader resonances. Although an increment in the dimension (diameter and height) of Au/Pd/Pt-nanoparticles decreases the absorption-to-scattering ratios, these ratios are less sensitive to the height size in Au-nanodisks, which causes their LSPR spectra become much broader. It is noteworthy that the LSPR quality factor of Pd nanoparticles is improved by considering the radiative damping and depolarization in quasi-static method unlike the Au nanoparticles. The importance of the highly absorptive Pd/Pt nanoparticles can be traced in the photo-functionalized and energy applications.

The significance of preoperative shoulder arthrography in painful arc patients

International Nuclear Information System (INIS)

Myllylae, V.; Jalovaara, P.; Pyhtinen, J.; Oulu Univ.

1984-01-01

Preoperative shoulder arthrography was performed on 34 patients with painful arc syndromes. Rotator cuff rupture was diagnosed in 20 cases. Out of these the arthrography correctly showed rupture in 17 cases, while in one case rupture was not seen and two examinations were unsuccessful. Rotator cuff rupture was found in 14 cases at operation. Of these, arthrography had been negative in eight cases and in six cases the rupture had merely been suspected. Sensitivity of shoulder arthrography in showing rotator cuff rupture was thus 85%, specificity 57% and accuracy 74%. The biceps tendon was intact in all cases with rotator cuff rupture. S-called ''bicipital leakage'' was seen in four cases, but its significance remains unclear. (orig.) [de

Arthrography in sport injuries of the knee joint

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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.

Arthrography in sport injuries of the knee joint

International Nuclear Information System (INIS)

Schaefer, H.

1983-01-01

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 frequently 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. (orig.)

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

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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.

Magnetic resonance tomography of the temporo-mandibular joints

International Nuclear Information System (INIS)

Katzberg, R.W.; Burgener, F.A.

1986-01-01

79 patients aged 6 to 66 years (9 men and 70 women) with abnormalities of the TMJs were examined by magnetic resonance tomography (132 joints) and the results were compared with CT (16 joints) and resonance tomography showed forward luxation of the meniscus in 82 joints (62%). In 34 joints (26%) the meniscus spontaneously resumed normal position when the mouth was open, but in 48 joints (36%) the displacement was permanent. The accuracy of resonance tomography was equal to that of arthrography and superior to CT. It was particularly suitable for follow-up examination after surgery (23 cases) when invasive arthrography would be contraindicated or difficult. Because of the high resolution of the soft tissue components in the TMJ, resonance tomography should be able to diagnose inflammatory and degenerative changes in the meniscus and ligaments. (orig.)

Shoulder instability: the role of MR arthrography in diagnosing anteroinferior labroligamentous lesions our experience at king hussein medical center

International Nuclear Information System (INIS)

Hiari, A. A.

2008-01-01

To determine the reliability and accuracy of magnetic resonance arthrography of the shoulder for the diagnosis of anteroinferior labroligamentous lesions in patients with gleno-humeral joint instability. This retrospective study was performed at King Hussein Medical Center in Jordan. Twenty eight patients who underwent shoulder MR arthrogram and arthroscopy during a 22-month period were reviewed. All the twenty eight patients had history of previous shoulder dislocation and clinical suspicion of anteroinferior labroligamentous lesions and glenohumeral joint instability. The series included 24 males and 4 females. The mean average age of the patients was 29 years. All patients underwent shoulder MR arthrogram and the results of MR arthrogram were compared with the arthroscopic findings which were used as the reference standard. MR arthrograms were analyzed for the presence and type of labroligamentous injuries which include (Bankart, anterior labral periosteal sleeve avulsion (ALPSA), Perthes, glenolabral articular disruption (GLAD), or nonclassifiable lesion). Sensitivity, specificity and accuracy for the detection and classification of anteroinferior labroligamentous lesions with MR arthrography were calculated. At arthroscopy, 21 anteroinferior labroligamentous lesions were diagnosed, including 15 Bankart lesions, three ALPSA lesions, two Perthes lesions and one GLAD lesion. Seven labral lesions were nonclassifiable at arthroscopy, all of which occurred after a history of chronic instability. When compared with arthroscopic findings, Shoulder MR Arthrography had two false-negative results (sensitivity, 92.8%) and no false-positive results. The sensitivity of shoulder MR Arthrography in detecting anteroinferior labroligamentous lesions was 92.8% (26/28) and specificity was (100%). The overall accuracy of Shoulder MR Arthrography in detecting labroligamentous lesions in this study was 90.5% (19/21). MR arthrography of the shoulder is reliable and accurate in

Double-compartment wrist arthrography

International Nuclear Information System (INIS)

Quinn, S.F.; Pittman, C.; Belsole, R.; Greene, T.L.; Rayhack, J.; Clark, R.A.; King, P.S.

1987-01-01

Seventy patients with clinical wrist problems were studied with double-compartment wrist arthrography. Midcarpal and radiocarpal compartment arthrograms were obtained in all patients. Digital subtraction technique was used to subtract out contrast from the first compartmental injection. Digital technique also allowed a dynamic record of each injection, which helped determine sites of intercompartmental communication. Postarthrography exercises recorded on videotape were performed after each injection. There were 34 normal studies. Abnormalities in the other 36 patients included: scapholunate communication (n = 9), lunatotriquetral communication (n = 6), communication with tendon sheaths (n = 4), communication with distal radioulnar compartment (n = 14), abnormal synovium process (n = 9), and communication through the radial or ulnar collateral ligament (n = 3). Double-compartment wrist arthrography may provide additional information for complex problems of the wrist

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

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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

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

International Nuclear Information System (INIS)

Cerezal, Luis; Fernandez-Hernando, Moises; Perez Carro, Luis; Llorca, Javier; Llopis, Eva; Montero, Juan Antonio; Canga, Ana

2015-01-01

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

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

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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

Rotator cuff ruptures of the shoulder joint, sonography - arthrography

International Nuclear Information System (INIS)

Triebel, H.J.; Wening, V.; Witte, G.; Hamburg Univ.

1986-01-01

47 patients suspected of rutpure of the rotator cuff were sonographed and arthrographed. Rupture of the rotator cuff was diagnosed in 12 cases, both diagnostic methods yielding the same result. In 29 patients sonography and arthrography did not reveal any abnormal findings. Six ruptures evident in sonography were not confirmed by arthrography and were considered false positive. Direct pointers towards rupture of the cuff would be: echoless defects, cuff cannot be visualised fully or in part and irregularities of movement during dynamic examination. Echoless 'cystic' areas in the periarticular soft parts must be considered an indirect pointer. Echorich focal findings in the echopoor cuff represent a differential diagnostic problem and we cannot give a final assessment as yet. Shoulder sonography is justified as a screening method in suspicion of rotator cuff rupture before initiating arthrography. If sonography reveals no abnormal findings, shoulder arthrography need not be performed. (orig.) [de

Mediopatellar phase of the knee: Comparative evaluation by arthrography and arthroscopy

International Nuclear Information System (INIS)

Schouman-Claeys, E.; Dupont, J.Y.; Frija, G.

1986-01-01

One hundred consecutive knees were examined by arthrography and arthroscopy in a prospective study to determine the diagnostic value of arthrography in the detection and characterization of mediopatellar phase (nonpathalogic vs. pathologic). Statistical tests show that there are only two significant signs for the diagnosis of pathologic mediopatellar phase: length and thickness, No method is significantly superior for determining the pathologic character of the phase. This study demonstrated that compared to arthroscopy, arthrography has good sensitivity (86%) and excellent specificity (99%) for the detection of mediopatellar phase. The authors conclude that arthrography is as efficient as arthroscopy for the evaluation of the mediopatellar phase syndrome

Radiologic evaluation of wrist arthrography

International Nuclear Information System (INIS)

Park, Yang Hee; Seong, Hyeun Lim; Yang, Jae Beom; Park, Chan Sup; Lee, Sang Seun

1991-01-01

Wrist arthrography allows direct visualization of the cartilage and synovial structure not seen in plain film. Arthrography of the wrist is valuable in evaluating patients with persistent wrist pain and limitation of motion after trauma. Wrist arthrography was performed in the evaluation of 30 patients with rheumatoid arthritis (2 cases), ganglions (12 cases), and wrist trauma (16 cases), and contrast media was injected in radiocarpal joint. The arthrographic findings were analyzed, and the results were as follows: In 16 patients with wrist trauma, 12 cases (75%) of compartment communication was seen including communication with distal radioulnar joint (44%), midcarpal joint (69%), and common carpometacarpal joint (63%). Of the total 30 patients, the pisiform-triquetral joint communicated with the radio carpal joint in 9 cases (30%). In 16 patients with trauma, the findings of post-traumatic arthritis included tendon communication (50%), irregular synovium (31%), and rupture of the joint capsule (25%). There was no lymphatic filling. Of 3 scaphoid fracture patients without bony callus formation, fibrous union was verified in one patient and nouncion in 2. O 12 patients with ganglion, communication between the ganglion and radiocarpal joint was seen in 2 cases and no communication in 10 cases

Value of arthrography after supination trauma of the ankle

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Dijk, C.N. van; Tol, J.L.; Marti, R.K. [Acad. Med. Centre, Amsterdam (Netherlands). Dept. of Orthopaedic Surg.; Molenaar, A.H.M. [Department of Radiology, Canisius Ziekenhuis, Weg door Jonkerbos 100, 6532 SZ Nijmegen (Netherlands); Cohen, R.H. [Department of Radiology, Stichting Ziekenhuis Amstelveen, Laan van de Helende Meesters 8, 1186 AM Amstelveen (Netherlands); Bossuyt, P.M.M. [Department of Epidemiology, Academic Medical Centre, P.O. Box 22700, 1100 DE Amsterdam (Netherlands)

1998-05-01

Objective. To investigate the merits of arthrography after supination trauma of the ankle. Design and patients. In a group of 160 consecutive patients operative exploration was performed in cases where arthrography and/or a delayed physical examination showed positive findings. In all patients arthrography was performed within 48 h after trauma. To determine interobserver agreement, all arthrograms were independently evaluated by two radiologists, both ignorant of the first assessment. Results. The prevalence of an ankle ligament lesion was found to be 76%. Of the 122 patients with a rupture of one or more ankle ligaments, 52% had an isolated anterior talofibular ligament lesion, 3% had an isolated calcaneofibular ligament lesion, and 45% had combined lesions. The site of the lesion was predominantly intraligamentous. In the determination of the presence or absence of an ankle ligament lesion, the specificity and sensitivity of the ankle arthrogram were 71% and 96% respectively. Interobserver agreement on the arthrogram was very good ({kappa} 0.9). In 1% of patients a clear diagnosis was not possible by means of arthrography. Conclusion. Arthrography provides information of high diagnostic quality with excellent interobserver agreement and therefore remains the gold standard for early diagnosis (within 48 h) of a lateral ankle ligament rupture. (orig.) With 4 figs., 5 tabs., 24 refs.

Value of arthrography after supination trauma of the ankle

International Nuclear Information System (INIS)

Dijk, C.N. van; Tol, J.L.; Marti, R.K.; Cohen, R.H.; Bossuyt, P.M.M.

1998-01-01

Objective. To investigate the merits of arthrography after supination trauma of the ankle. Design and patients. In a group of 160 consecutive patients operative exploration was performed in cases where arthrography and/or a delayed physical examination showed positive findings. In all patients arthrography was performed within 48 h after trauma. To determine interobserver agreement, all arthrograms were independently evaluated by two radiologists, both ignorant of the first assessment. Results. The prevalence of an ankle ligament lesion was found to be 76%. Of the 122 patients with a rupture of one or more ankle ligaments, 52% had an isolated anterior talofibular ligament lesion, 3% had an isolated calcaneofibular ligament lesion, and 45% had combined lesions. The site of the lesion was predominantly intraligamentous. In the determination of the presence or absence of an ankle ligament lesion, the specificity and sensitivity of the ankle arthrogram were 71% and 96% respectively. Interobserver agreement on the arthrogram was very good (κ 0.9). In 1% of patients a clear diagnosis was not possible by means of arthrography. Conclusion. Arthrography provides information of high diagnostic quality with excellent interobserver agreement and therefore remains the gold standard for early diagnosis (within 48 h) of a lateral ankle ligament rupture. (orig.)

Articular cartilage defect detectability in human knees with MR-arthrography

International Nuclear Information System (INIS)

Engel, A.; Kramer, J.; Stiglbauer, R.; Hajek, P.C.; Imhof, H.

1993-01-01

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.)

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.)

Magnetic resonance arthrography and the prevalence of acetabular labral tears in patients 50 years of age and older

International Nuclear Information System (INIS)

Jayakar, Rohit; Merz, Alexa; Wang, Dean; Hame, Sharon L.; Plotkin, Benjamin; Seeger, Leanne

2016-01-01

Arthroscopy for acetabular labral tears has minimal impact on pain and function in older patients, especially in the setting of concomitant osteoarthritis. Still, many physicians seek this diagnosis with MR arthrography. Our purpose is to assess the frequency of acetabular labral tears in older patients with hip pain and correlate likelihood of labral pathology with severity of osteoarthritis as visualized on conventional radiograph. From 2004 to 2013, 208 hip MRI arthrograms and corresponding radiographs on patients aged 50 years and older were identified. Age, gender, grade and location of labral tear, alpha angle, Toennis grade, and joint space width were documented. Labral tears and alpha angle were identified and measured on MR arthrogram. Toennis grade and joint space width were measured on radiographs. On MR arthrography, true labral tearing was identified in 73 % of patients. There was some degree of labral pathology in 93.3 % of patients, and this increased to 100 % in patients with moderate to severe osteoarthritis, as defined by Toennis grade 2-3 or joint space width ≤ 2 mm. There were no statistically significant correlations between labral tear grade and Toennis grade or joint space width. Given the high frequency of labral pathology and the questionable efficacy of arthroscopic surgical intervention in older patients, MR arthrography should be primarily for those with minimal arthritis on radiograph and potential to benefit from surgery. If further imaging beyond radiographs is necessary in these patients, standard MRI may be a more appropriate imaging tool. (orig.)

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

International Nuclear Information System (INIS)

Hu, Jin Guang; Lee, Jong Min; Ryeom, Hun Kyu

2005-01-01

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

Optimization of T2-weighted imaging for shoulder magnetic resonance arthrography by synthetic magnetic resonance imaging.

Science.gov (United States)

Lee, Seung Hyun; Lee, Young Han; Hahn, Seok; Yang, Jaemoon; Song, Ho-Taek; Suh, Jin-Suck

2017-01-01

Background Synthetic magnetic resonance imaging (MRI) allows reformatting of various synthetic images by adjustment of scanning parameters such as repetition time (TR) and echo time (TE). Optimized MR images can be reformatted from T1, T2, and proton density (PD) values to achieve maximum tissue contrast between joint fluid and adjacent soft tissue. Purpose To demonstrate the method for optimization of TR and TE by synthetic MRI and to validate the optimized images by comparison with conventional shoulder MR arthrography (MRA) images. Material and Methods Thirty-seven shoulder MRA images acquired by synthetic MRI were retrospectively evaluated for PD, T1, and T2 values at the joint fluid and glenoid labrum. Differences in signal intensity between the fluid and labrum were observed between TR of 500-6000 ms and TE of 80-300 ms in T2-weighted (T2W) images. Conventional T2W and synthetic images were analyzed for diagnostic agreement of supraspinatus tendon abnormalities (kappa statistics) and image quality scores (one-way analysis of variance with post-hoc analysis). Results Optimized mean values of TR and TE were 2724.7 ± 1634.7 and 80.1 ± 0.4, respectively. Diagnostic agreement for supraspinatus tendon abnormalities between conventional and synthetic MR images was excellent (κ = 0.882). The mean image quality score of the joint space in optimized synthetic images was significantly higher compared with those in conventional and synthetic images (2.861 ± 0.351 vs. 2.556 ± 0.607 vs. 2.750 ± 0.439; P optimized TR and TE for shoulder MRA enables optimization of soft-tissue contrast.

Ultrasonography and arthrography in rotator cuff lesions: algorithmic approach

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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.

Ultrasonography and arthrography in rotator cuff lesions: algorithmic approach

International Nuclear Information System (INIS)

Kim, Eui Jong; Ryu, Kyung Nam; Lee, Sun Wha; Lim, Jae Hoon; Rhee, Yong Girl; Yu, Pil Mun

1992-01-01

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

The Usefulness of Dynamic Cine-Arthrography for Wrist Instability as Correlated with Arthroscopic Palmer Classification

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Kim TaeYeon; Lee, Guen Young; Kim, Baek Hyun; Park, Jong Woong; Seo, Bo Kyoung; Cha, Sang Hoon [Korea University Ansan Hospital, Korea University College of Medicine, Ansan (Korea, Republic of)

2011-05-15

To introduce dynamic cine-arthrography and compare it with MR arthrography in the diagnosis of intrinsic ligament and triangular fibrocartilage complex tears, based on arthroscopic findings. A total of thirty-eight wrists of 38 patients who had undergone both dynamic cine-arthrography and MR arthrography were enrolled. Dynamic cinearthrography was performed after puncture of the radiocarpal joint by slow injection of contrast under continuous fluoroscopic guidance during passive wrist exercise. We obtained 1.5- or 3-T MR arthrography with fat-suppressed T1-weighted coronal and axial images. We evaluated scapholunate and lunotriquetral ligaments and triangular fibrocartilage complex tears according to the Palmer classification system. Based on the arthroscopic findings, we compared the diagnostic values between the two examinations using Kappa values. The overall sensitivity and specificity of diagnosis of intrinsic ligament tears was similar between dynamic cine-arthrography and MR arthrography (scapholunate ligament: sensitivity 66.7% vs. 80%, specificity 100% vs. 95.7%, lunotriquetral ligament: sensitivity 75.0% vs. 75.0%, specificity 94.1% vs. 91.2%). For triangular fibrocartilage complex tears, all diagnostic values were the same (sensitivity 96.4%, specificity 100%). The inter-examination agreement was substantial to perfect (kappa value 1.000). Dynamic cine-arthrography is valuable in the diagnosis of intrinsic ligament and triangular fibrocartilage complex tears compared to MR arthrography.

Single and double contrast arthrography in lesions of the glenohumeral joint

International Nuclear Information System (INIS)

Ahovuo, J.

1984-01-01

One hundred and forty-five arthrograms from single and double contrast arthrography were compared with respect to their accuracy in revealing lesions of the glenohumeral joint. Total and partial rotator cuff tears were accurately delineated by both single and double contrast arthrography. The size of the tear did not correlate with surgical findings with either technique. The volume of the injected contrast medium was larger in full-thickness rotator cuff tears than in normal arthrograms (p 2 test). No difference in filling frequency of the sheath could be observed between single and double contrast arthrography. This study did not reveal any major advantages of double contrast arthrography over single contrast examinations in lesions of the rotator cuff and those of the tendon of the long head of the biceps brachii. (orig.)

MR arthrography: Basics, technique, and first results

International Nuclear Information System (INIS)

Hajek, P.C.; Engel, A.; Kramer, J.; Imhof, H.

1988-01-01

Following evidence that intraarticular Gd-DTPA does not induce synovitis and is not stored in normal or chondropathic joint cartilage, the authors injected various concentrations of Gd-DTPA into 40 cadaveric and 40 in vivo knees. All in vivo knees underwent total prosthetic knee replacement, followed by a histologic workup. Results showed that MR arthrography greatly enhances the visibility of normal and pathologic structures and is a safe procedure. Moreover, MR arthrography seems to allow correct assessment and staging of various types of chondropathies

The role of pubic symphyseal CT arthrography in the imaging of athletic pubalgia.

Science.gov (United States)

McArthur, Tatum A; Narducci, Carl A; Lopez-Ben, Robert R

2014-11-01

The purpose of this article is to describe the results of pubic symphyseal CT arthrography compared with MRI in patients with suspected athletic pubalgia. In this study, two musculoskeletal radiologists retrospectively searched our department's PACS to identify patients who had undergone CT-guided injection with concurrent pubic symphyseal CT arthrography for evaluation and treatment of groin pain, sports hernia, or athletic pubalgia over a 5.5-year period (January 1, 2007-July 1, 2012). The MR and CT arthrography images and reports, clinical findings at presentation, pain response to injection, and operative findings were reviewed using the electronic medical record. Twelve patients underwent CT-guided injection and pubic symphyseal CT arthrography at our institution during the 5.5-year study period. Nine of the 12 patients had undergone MRI before the procedure. In two of the three patients who had not undergone MRI, CT arthrography revealed secondary clefts. Three of four patients who had secondary clefts on MRI had contrast extravasation reproducing the cleft at CT. Three patients had MRI findings suggestive of athletic pubalgia without MRI evidence of a secondary cleft; in all three of these patients, CT arthrography showed a secondary cleft. In four patients, CT arthrography revealed tendon tears at the adductor origin that were not apparent on MRI. All 12 patients reported decreased groin pain after injection. Pubic symphyseal CT arthrography is a useful technique for the diagnosis and short-term pain relief of athletic pubalgia. It can be used to identify secondary clefts and to detect tendon tears that can potentially be overlooked on MRI.

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.)

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

International Nuclear Information System (INIS)

Gokalp, Gokhan; Dusak, Abdurrahim; Yazici, Zeynep

2010-01-01

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.)

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.

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

International Nuclear Information System (INIS)

Lee, Ji Hyun; Yoon, Young Cheol; Kwon, Jong Won; Yoo, Jae Chul; Cha, Jang Kyu; Jee, Suk Kyoung

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.

Diagnosis of triangular fibrocartilage complex injury using arthrography and MRI

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Kato, Kiyonobu; Soejima, Osamu; Naito, Masatoshi [Fukuoka Univ. (Japan). School of Medicine

2001-09-01

Twenty patients (twenty-one wrists) with chronic ulnar wrist pain who had undergone radiocarpal arthrography and MRI before arthroscopic examination were evaluated to determine the usefulness of these preoperative diagnostic procedures (arthrogrphy and MRI) for the detection of triangular fibrocartilage complex (TFCC) injury. Based on the arthroscopic findings, the sensitivity and specificity of arthrography were 63% and 100% respectively for detecting TFCC lesions, while they were 68% and 50% respectively for MRI. Although no significant superiority was observed between arthrography and MRI in this study, further improrumchts in the preoperative diagnostic procedures are still needed in order to more accurately detect TFCC injuries. (author)

Indirect MR arthrography of the shoulder in detection of rotator cuff ruptures

International Nuclear Information System (INIS)

Yagci, B.; Manisali, M.; Yilmaz, E.; Oezaksoy, D.; Kovanlikaya, I.; Oezkan, M.; Ekin, A.

2001-01-01

The aim of this study was to compare the efficacy of indirect MR arthrography images obtained following intravenous contrast injection and conventional MR imaging in the diagnosis of rotator cuff tears. Twenty-four patients with clinically suspected rotator cuff disease were examined. Conventional MR images and post-contrast indirect MR arthrography images were obtained. All images were evaluated in a blinded fashion by two musculoskeletal radiologist. Results were than analyzed depending on surgical output. The correlation coefficient (Spearman rank correlation test) and the kappa values for agreement between surgery and imaging techniques were calculated. The correlation coefficients between indirect MR arthrography and surgery for reader 1 and reader 2 were 0.9137 and 0.9773, respectively. Whereas the agreement between conventional MR imaging and surgery was moderate (κ=0.383-0.571), the agreement between indirect MR arthrography and surgery was excellent (κ=0.873-0.936). We suggest the use of indirect MR arthrography technique when conventional MR images are equivocal in diagnosis of rotator cuff disease. (orig.)

Feasibility of ultrasound-guided intraarticular contrast injection for MR arthrography

International Nuclear Information System (INIS)

Baek, Soo Jin; Lee, Jong Min; Kang, Duck Sick

2005-01-01

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

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.

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

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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.)

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

International Nuclear Information System (INIS)

Jordan, R.W.; Naeem, R.; Srinivas, K.; Shyamalan, G.

2015-01-01

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.)

The significance of arthrography and arthroscopy in the diagnosis of meniscus injury

International Nuclear Information System (INIS)

Eckel, H.; Linder, J.; Petzold, M.V.; Meyne, K.; Doerges, J.; Evangelisches Krankenhaus Goettingen

1981-01-01

The article reports on 364 double-contrast arthrographics and 185 arthroscopies.The results obtained in 126 patients in whom both arthrography and arthroscopy had been conducted, were compared. It became evident that arthrography is of high informative value in the diagnosis of lesions of the meniscus, so that preference may well be given to this method in non-specific knee-joint complaints where meniscopathy is suspected. Arthroscopies are indicated in cases of clinico-arthrographic coubt. Trial arthrotomy for clarifying doubtful meniscus lesions without previous exploitation of all arthrographic/arthroscopic possibilities is no longer justified and should be abandoned. Arthroscopy is definitely superior to arthrography in the diagnosis of, in particular, cartilage structures, of the synovia and of the retropatellar space. It is here where arthrography has its narrow limitations - now and in the future - for methodical reasons. (orig.) [de

Broader energy distribution of CO adsorbed at polycrystalline Pt electrode in comparison with that at Pt(111) electrode in H_2SO_4 solution confirmed by potential dependent IR/visible double resonance sum frequency generation spectroscopy

International Nuclear Information System (INIS)

Yang, Shuo; Noguchi, Hidenori; Uosaki, Kohei

2017-01-01

Highlights: • Electrochemical SFG spectroscopy is an efficient in situ probe of electronic structure at electrochemical interface. • Electrooxidation performances of CO adsorbed on polycrystalline Pt and Pt(111) electrodes were compared. • The enhanced SFG signal of CO on Pt electrodes was observed due to a vibrational-electronic double resonance effect. • The broader energy distribution of 5sa state of CO on polycrystalline Pt than on Pt(111) is proved by SFG results. - Abstract: Electrochemical cyclic voltammetry and potential dependent double resonance sum frequency generation (DR-SFG) spectroscopy were performed on CO adsorbed on polycrystalline Pt and Pt(111) electrodes in H_2SO_4 solution to examine the effect of substrate on the electronic structure of CO. The dependence of SFG intensity on potential and visible energy for atop CO band was observed on both polycrystalline and single crystalline Pt electrodes. Enhancement of the SFG intensity was determined to be a direct result of a surface electronic resonance of the visible/SF light with the electronic transition from Fermi level of Pt to the 5σ_a anti-bonding state of adsorbed CO, in agreement with previous results. Interestingly, when compared to the Pt(111) electrode, the distribution width of the intensity enhancement region on polycrystalline Pt is broader than on Pt(111). This suggests that the energy distribution of the 5σ_a state of CO on polycrystalline Pt surface is broader than that on Pt(111) due to the complex surface structure of the polycrystalline Pt electrode.

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

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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.)

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

International Nuclear Information System (INIS)

Jung, Jee Young; Yoon, Young Cheol; Yi, Sang-Kyu; Yoo, Jaechul; Choe, Bong-Keun

2009-01-01

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 (κ > 0.41) with both methods. Based on a relatively small number of patients, no significant

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

Triple correlation in temporomandibular joint dysfunction: MR imaging with arthrography, arthroscopy, and open surgery

International Nuclear Information System (INIS)

Rao, V.M.; Farole, A.; Karasick, D.

1988-01-01

Triple correlation of MR imaging with arthrography, arthroscopy, and open surgery was performed in 24 patients (34 temporomandibular joints) with ages ranging from 17 to 66 years. MR imaging showed disk position and morphologic features accurately in 30 joints (88%). It was false negative in one joint and false positive in three joints (9%). Degenerative changes were accurately detected with MR imaging, arthrography, and arthroscopy. Adhesions were diagnosed with arthrography in eight joints, arthroscopy in 14, and MR imaging in none. Disk perforations seen at open surgery were not detected with MR imaging. In conclusion, there is an overlap of information presented by various modalities. MR imaging is better than arthrography detecting disk morphologic features and displacement. Arthrography may add information by showing meniscal dynamics. Arthroscopy entails direct observation of superior joint space only and can detect adhesions and perforations better, but it may alter disk position and dynamics. In the more difficult cases, triple correlation may be needed, as modalities can be complementary

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

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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.

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

International Nuclear Information System (INIS)

Nakanishi, Katsunuki; Masatomi, Takashi; Ochi, Takahiro; Ishida, Takeshi; Hori, Shinichi; Ikezoe, Junpei; Nakamura, Hironobu

1996-01-01

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

Technical errors in MR arthrography

International Nuclear Information System (INIS)

Hodler, Juerg

2008-01-01

This article discusses potential technical problems of MR arthrography. It starts with contraindications, followed by problems relating to injection technique, contrast material and MR imaging technique. For some of the aspects discussed, there is only little published evidence. Therefore, the article is based on the personal experience of the author and on local standards of procedures. Such standards, as well as medico-legal considerations, may vary from country to country. Contraindications for MR arthrography include pre-existing infection, reflex sympathetic dystrophy and possibly bleeding disorders, avascular necrosis and known allergy to contrast media. Errors in injection technique may lead to extra-articular collection of contrast agent or to contrast agent leaking from the joint space, which may cause diagnostic difficulties. Incorrect concentrations of contrast material influence image quality and may also lead to non-diagnostic examinations. Errors relating to MR imaging include delays between injection and imaging and inadequate choice of sequences. Potential solutions to the various possible errors are presented. (orig.)

Technical errors in MR arthrography

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Hodler, Juerg [Orthopaedic University Hospital of Balgrist, Radiology, Zurich (Switzerland)

2008-01-15

This article discusses potential technical problems of MR arthrography. It starts with contraindications, followed by problems relating to injection technique, contrast material and MR imaging technique. For some of the aspects discussed, there is only little published evidence. Therefore, the article is based on the personal experience of the author and on local standards of procedures. Such standards, as well as medico-legal considerations, may vary from country to country. Contraindications for MR arthrography include pre-existing infection, reflex sympathetic dystrophy and possibly bleeding disorders, avascular necrosis and known allergy to contrast media. Errors in injection technique may lead to extra-articular collection of contrast agent or to contrast agent leaking from the joint space, which may cause diagnostic difficulties. Incorrect concentrations of contrast material influence image quality and may also lead to non-diagnostic examinations. Errors relating to MR imaging include delays between injection and imaging and inadequate choice of sequences. Potential solutions to the various possible errors are presented. (orig.)

Intrinsic ligament and triangular fibrocartilage complex tears of the wrist: comparison of MDCT arthrography, conventional 3-T MRI, and MR arthrography

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

2013-09-15

This study compares the diagnostic performance of multidetector CT arthrography (CTA), conventional 3-T MR and MR arthrography (MRA) in detecting intrinsic ligament and triangular fibrocartilage complex (TFCC) tears of the wrist. Ten cadaveric wrists of five male subjects with an average age 49.6 years (range 26-59 years) were evaluated using CTA, conventional 3-T MR and MRA. We assessed the presence of scapholunate ligament (SLL), lunotriquetral ligament (LTL), and TFCC tears using a combination of conventional arthrography and arthroscopy as a gold standard. All images were evaluated in consensus by two musculoskeletal radiologists with sensitivity, specificity, and accuracy being calculated. Sensitivities/specificity/accuracy of CTA, conventional MRI, and MRA were 100 %/100 %/100 %, 66 %/86 %/80 %, 100 %/86 %/90 % for the detection of SLL tear, 100 %/80 %/90 %, 60 %/80 %/70 %, 100 %/80 %/90 % for the detection of LTL tear, and 100 %/100 %/100 %, 100 %/86 %/90 %, 100 %/100 %/100 % for the detection of TFCC tear. Overall CTA had the highest sensitivity, specificity, and accuracy among the three investigations while MRA performed better than conventional MR. CTA also had the highest sensitivity, specificity, and accuracy for identifying which component of the SLL and LTL was torn. Membranous tears of both SLL and LTL were better visualized than dorsal or volar tears on all three imaging modalities. Both CT and MR arthrography have a very high degree of accuracy for diagnosing tears of the SLL, LTL, and TFCC with both being more accurate than conventional MR imaging. (orig.)

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.

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

International Nuclear Information System (INIS)

Kang, Yeon Ah; Lee, Guen Young; Lee, Joon Woo; Lee, Eugene; Kim, Boh Young; Kim, Su Jin; Ahn, Joong Mo; Kang, Heung Sik

2017-01-01

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

Sacro-iliac joint arthrography in low back pain: feasibility of MRI guidance

International Nuclear Information System (INIS)

Ojala, Risto; Klemola, Rauli; Karppinen, Jaro; Sequeiros, Roberto Blanco; Tervonen, Osmo

2001-01-01

Objective: Evaluation of the feasibility of MR-guidance in sacro-iliac joint arthrography in patients whose low back pain is suspected to arise from the sacro-iliac joint (SIJ). Methods and patients: Twenty patients with low back pain underwent MR-guided sacro-iliac joint arthrography. Needles made from titanium (size 20 G, MDTech, USA) were used. For image guidance a 0.23T open-configuration C arm magnet (Proview, Marconi Medical Systems, USA) with special interventional hardware and software package (I-Path 200, Marconi Medical Systems) containing an MR compatible in-room console, large-screen (36'') display, optical navigator and accompanying software with dedicated sequences was used. No other image guidance modalities were used. Results: MR-guided SIJ arthrography was successfully performed in all twenty patients without complications. The optimal imaging sequence both for preoperative and intraoperative images was 3D-Gradient Echo sequence. The dispersal of the injected saline and anaesthetic could be determined inside the joint in all cases with heavily T2-weighted fast spin echo sequence. In the present study, 60% of the patients had significant reduction of pain after sacro-iliac joint arthrography and sacro-iliac joint was considered to be the source of patients low back pain in these patients. Conclusion: The present study shows that MR guidance with open configuration low field scanner is an accurate guiding method for sacro-iliac joint arthrography

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

International Nuclear Information System (INIS)

Kang, Chang Ho; Kim, Sam Soo; Kim, Jung Hyuk; Chung, Kyoo Byung; Kim, Yun Hwan; Oh, Yu-Whan; Jeong, Woong-Kyo; Kim, Baek Hyun

2009-01-01

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 ( 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.)

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

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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.)

Scatter radiation exposure during knee arthrography

International Nuclear Information System (INIS)

Light, M.C.; Molloi, S.Y.; Yandow, D.R.; Ranallo, F.N.

1987-01-01

Knee arthrography, as performed at the authors' institution, was simulated and scattered radiation exposure to a radiologist's gonads, thyroid, and eye lens was measured with a sensitive ionization chamber. Results show that radiologists who regularly conduct knee arthrography examinations can incur doses to the gonads that are less than 6% of the U.S. limits, and to the thyroid and eye that are approximately 10% of the U.S. limits. Since the scatter radiation from overhead imaging of stress views constituted most (greater than or equal to 60%) of the dose to the lens of the eye and the thyroid, spot imaging was evaluated as a substitute for overhead imaging in the assessment of the anterior cruciate ligament. This substitution resulted in no loss of clinical information and has now completely replaced overhead imaging of stress views at this institution

Site selective substitution Pt for Ti in KTiOPO{sub 4}:Ga crystals revealed by electron paramagnetic resonance

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Grachev, V.; Meyer, M.; Jorgensen, J.; Malovichko, G. [Department of Physics, Montana State University, Bozeman, Montana 59717 (United States); Hunt, A. W. [Idaho Accelerator Center, Idaho State University, Pocatello, Idaho 83209 (United States)

2014-07-28

Electron Paramagnetic Resonance at low temperatures has been used to characterize potassium titanyl phosphate (KTiOPO{sub 4}) single crystals grown by different techniques. Irradiation with 20 MeV electrons performed at room temperature and liquid nitrogen temperature caused an appearance of electrons and holes. Platinum impurities act as electron traps in KTiOPO{sub 4} creating Pt{sup 3+} centers. Two different Pt{sup 3+} centers were observed, Pt(A) and Pt(D). The Pt(A) centers are dominant in undoped samples, whereas Pt(D)—in Ga-doped KTP crystals. Superhyperfine structure registered for Pt(D) centers was attributed to interactions of platinum electrons with {sup 39}K and two {sup 31}P nuclei in their surroundings. In both Pt(A) and Pt(D) centers, Pt{sup 3+} ions substitute for Ti{sup 4+} ions, but with a preference to one of two electrically distinct crystallographic positions. The site selective substitution can be controlled by the Ga-doping.

Arthrography of the hip in children

International Nuclear Information System (INIS)

Loennerholm, T.

1980-01-01

A method by which bilateral hip arthrography was performed under general anaesthesia in 130 infants and children 1 month to 7 years of age is described. Significant contractures of the adductor muscles had been corrected before the examination. Most of the children were girls with unilateral congenital idiopathic hip instability detected before the age of one year. From films exposed in standardized projections valuable information was obtained about the configuration of the joint cavity and the size and shape of the femoral head. Criteria for normal appearance in infants of ages 2 to 12 months are presented. More reliable details on the relation between the articular surfaces, the radiographic anatomy of the acetabulum and the distribution of the contrast medium were yielded by stereoradiography. Closed reduction was usually accomplished successfully during the arthrography, which made beginning of definitive treatment under the same anaesthesia possible. (Auth.)

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?

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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.)

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

International Nuclear Information System (INIS)

Kreitner, K.-F.; Thelen, M.; Loew, R.; Runkel, M.; Zoellner, J.

2003-01-01

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.)

Arthrography of the TMJ. Indications, technique and interpretation

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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.

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

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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.

The posterior transtriceps approach for elbow arthrography: a forgotten technique?

International Nuclear Information System (INIS)

Lohman, M.; Borrero, C.; Casagranda, B.; Rafiee, B.; Towers, J.

2009-01-01

To evaluate the technical feasibility of performing elbow MR arthrography via a posterior approach through the triceps. The images of 19 patients with elbow MR arthrography via a posterior transtriceps approach were retrospectively studied. The injections were performed by four musculoskeletal radiologists, using fluoroscopic guidance and a 22- or 25-gauge needle. The fluoroscopic and subsequent MR images were reviewed by two musculoskeletal radiologists and evaluated for adequacy of joint capsular distention, degree and location of contrast leakage, and presence of gas bubbles. The injection was diagnostic in all 19 patients, with a sufficient amount of contrast agent seen in the elbow joint. No significant contrast leakage occurred in 12 patients who received injections of 8 cc or less of contrast agent, but moderate contrast leakage occurred in 6/7 patients who received injections of greater than 8 cc. Contrast leakage generally occurred within the triceps myotendinous junction. No gas bubbles were identified in the injected joints. Patients often present for MR arthrography of the elbow with medial or lateral elbow pain. Contrast leakage during a radiocapitellar approach may complicate evaluation of the lateral collateral ligament or the common extensor tendon origin. Transtriceps MR arthrography offers an alternative to the more commonly used radiocapitellar approach. With injected volumes not exceeding 8 cc, the risk of significant contrast leakage is small. An advantage of the transtriceps injection is that contrast leakage through the posterior needle tract does not interfere with evaluation of the lateral structures. (orig.)

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.)

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

International Nuclear Information System (INIS)

Fallahi, Farshid; Green, Nick; Gadde, Sarat; Jeavons, Lisa; Armstrong, Patrick; Jonker, Leon

2013-01-01

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.)

[Arthrography of the temporomandibular joint. Indications, technic and interpretation].

Science.gov (United States)

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.

Evaluation of Labral Pathology and Hip Articular Cartilage in Patients with Femoroacetabular Impingement (FAI): Comparison of Multidetector CT Arthrography and MR Arthrography

International Nuclear Information System (INIS)

Sahin, Murat; Calisir, Cuneyt; Omeroglu, Hakan; Inan, Ulukan; Mutlu, Fezan; Kaya, Tamer

2014-01-01

To compare the multidetector computed tomography (MDCT) arthrography (CTa) and magnetic resonance (MR) arthrography (MRa) findings with surgical findings in patients with femoroacetabular impingement (FAI) and to evaluate the diagnostic performance of these methods. Labral pathology and articular cartilage were prospectively evaluated with MRa and CTa in 14 hips of 14 patients. The findings were evaluated by two musculoskeletal radiologists with 10 and 20 years of experience, respectively. Sensitivity, specificity, accuracy, and positive predictive value were determined using surgical findings as the standard of reference. While the disagreement between observers was recorded in two cases of labral tearing with MRa, there was a complete consensus with CTa. Disagreement between observers was found in four cases of femoral cartilage loss with both MRa and CTa. Disagreement was also recorded in only one case of acetabular cartilage loss with both methods. The percent sensitivity, specificity, and accuracy for correctly assessing the labral tearing were as follows for MRa/CTa, respectively: 100/100, 50/100, 86/100 (p<0.05). The same values for acetabular cartilage assessment were 89/56, 40/60, 71/71 (p>0.05) and for femoral cartilage assessment were 100/75, 90/70, 86/71 (p>0.05). Inter-observer reliability value showed excellent agreement for labral tearing with CTa (κ=1.0). Inter-observer agreement was substantial to excellent with regard to acetabular cartilage assessment with MRa and CTa (κ=0.76 for MRa and κ=0.86 for CTa) Inter-observer reliability with CTa is excellent for labral tearing assessment. CTa seems to have an equal sensitivity and a higher specificity than MRa for the detection of labral pathology. MRa is better, but not statistically significantly, in demonstrating acetabular and femoral cartilage pathology

Adhesive capsulitis of the shoulder: evaluation with MR arthrography

International Nuclear Information System (INIS)

Jung, Joon-Yong; Jee, Won-Hee; Chun, Ho Jong; Kim, Yang-Soo; Chung, Yang Guk; Kim, Jung-Man

2006-01-01

The purpose of this study was to determine the usefulness of magnetic resonance (MR) arthrography for diagnosing adhesive capsulitis. Shoulder MR images of 28 patients with (n=14) and without (n=14) adhesive capsulitis were retrospectively analyzed. MR images were assessed for capsule and synovium thickness as well as the width of the axillary recess on oblique coronal fat-suppressed T1-weighted images and T2-weighted images, respectively. On oblique sagittal fat-suppressed T1-weighted images, the width of the rotator interval and the presence of abnormal tissue in the interval were evaluated. Significant differences were found between the two groups in capsule and synovium thickness on both sides of the recess on oblique coronal T2-weighted images (P=0.000), whereas thickness on the humeral aspect showed no significant difference on oblique coronal fat-suppressed T1-weighted images (P=0.109). On oblique coronal T2-weighted images, a cut-off value of 3-mm thickness gave the highest diagnostic accuracy for adhesive capsulitis with sensitivity, specificity, and accuracy of 79% (11/14), 100% (14/14), and 89% (25/28) at the humeral side and 93% (13/14), 86% (12/14), and 89% (25/28) at the glenoid side, respectively. There were significant differences in rotator interval width, presence of abnormal tissue in the rotator interval, and axillary recess width between the two groups (P<0.05). Thickness of capsule and synovium of the axillary recess greater than 3 mm is a practical MR criterion for diagnosing adhesive capsulitis when measured on oblique coronal T2-weighted MR arthrography images without fat suppression. The presence of abnormal tissue in the rotator interval showed high sensitivity but rather low specificity. (orig.)

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.)

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

International Nuclear Information System (INIS)

Helms, Clyde A.; McGonegle, Shane J.; Vinson, Emily N.; Whiteside, Michael B.

2011-01-01

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.)

The clinical and radiological importance of extraarticular contrast material leakage into adjacent synovial compartments on ankle MR arthrography in patients with OCD and anterolateral impingement

Energy Technology Data Exchange (ETDEWEB)

Ogul, Hayri, E-mail: drhogul@gmail.com [Department of Radiology, Medical Faculty, Ataturk University, Erzurum (Turkey); Guzel, Yunus [Department of Orthopaedics and Traumatology, Medical Faculty, Ordu University, Ordu (Turkey); Pirimoglu, Berhan [Department of Radiology, Medical Faculty, Ataturk University, Erzurum (Turkey); Tuncer, Kutsi [Department of Orthopedic, Medical Faculty, Ataturk University, Erzurum (Turkey); Polat, Gokhan; Ergun, Fatih; Sade, Recep; Bayraktutan, Ummugulsum; Yuce, Ihsan; Kantarci, Mecit [Department of Radiology, Medical Faculty, Ataturk University, Erzurum (Turkey)

2016-10-15

Purpose: To evaluate the tibiotalar joint capacity and the localisation, frequency and amount of extravasation in patients with extraarticular contrast material leakage into adjacent synovial compartments on ankle magnetic resonance (MR) arthrography. Materials and methods: Sites of extravasation were determined in the ankle MR arthrograms of 69 patients. Thirty-four patients without extraarticular contrast material leakage into locations unrelated to the injection path were included as a control group. Volumetric measurements of extraarticular contrast material leakage and the tibiotalar joint capacity were performed on a three dimensional (3D) volume measurement workstation. Results: Extravasation of contrast material occurred through the anterior, posterior, and anterolateral recesses of the tibiotalar joint. The most common site of extravasation was along the flexor hallucis longus tendon synovium (24.6%). The amount of extravasation was significantly higher in patients with ankle osteochondritis dissecans (OCD) than in patients with a different diagnosis (p = 0.039). Loose bodies were detected in all OCD’s patients with insufficient tibiotalar joint distention. Conclusions: Connections between the ankle joint and neighboring synovial compartments can decrease the diagnostic value of ankle MR arthrography examinations due to inadequate joint distention. Large injection volumes should be used for ankle MR arthrography of patients with OCD (especially OCD’s patients with loose body) and impingement syndrome.

The clinical and radiological importance of extraarticular contrast material leakage into adjacent synovial compartments on ankle MR arthrography in patients with OCD and anterolateral impingement

International Nuclear Information System (INIS)

Ogul, Hayri; Guzel, Yunus; Pirimoglu, Berhan; Tuncer, Kutsi; Polat, Gokhan; Ergun, Fatih; Sade, Recep; Bayraktutan, Ummugulsum; Yuce, Ihsan; Kantarci, Mecit

2016-01-01

Purpose: To evaluate the tibiotalar joint capacity and the localisation, frequency and amount of extravasation in patients with extraarticular contrast material leakage into adjacent synovial compartments on ankle magnetic resonance (MR) arthrography. Materials and methods: Sites of extravasation were determined in the ankle MR arthrograms of 69 patients. Thirty-four patients without extraarticular contrast material leakage into locations unrelated to the injection path were included as a control group. Volumetric measurements of extraarticular contrast material leakage and the tibiotalar joint capacity were performed on a three dimensional (3D) volume measurement workstation. Results: Extravasation of contrast material occurred through the anterior, posterior, and anterolateral recesses of the tibiotalar joint. The most common site of extravasation was along the flexor hallucis longus tendon synovium (24.6%). The amount of extravasation was significantly higher in patients with ankle osteochondritis dissecans (OCD) than in patients with a different diagnosis (p = 0.039). Loose bodies were detected in all OCD’s patients with insufficient tibiotalar joint distention. Conclusions: Connections between the ankle joint and neighboring synovial compartments can decrease the diagnostic value of ankle MR arthrography examinations due to inadequate joint distention. Large injection volumes should be used for ankle MR arthrography of patients with OCD (especially OCD’s patients with loose body) and impingement syndrome.

[Technique and value of direct MR arthrography applying articular distraction].

Science.gov (United States)

Becce, Fabio; Wettstein, Michael; Guntern, Daniel; Mouhsine, Elyazid; Palhais, Nuno; Theumann, Nicolas

2010-02-24

Direct MR arthrography has a better diagnostic accuracy than MR imaging alone. However, contrast material is not always homogeneously distributed in the articular space. Lesions of cartilage surfaces or intra-articular soft tissues can thus be misdiagnosed. Concomitant application of axial traction during MR arthrography leads to articular distraction. This enables better distribution of contrast material in the joint and better delineation of intra-articular structures. Therefore, this technique improves detection of cartilage lesions. Moreover, the axial stress applied on articular structures may reveal lesions invisible on MR images without traction. Based on our clinical experience, we believe that this relatively unknown technique is promising and should be further developed.

Tuning magnetic properties of non-collinear magnetization configuration in Pt/[Pt/Co]{sub 6}/Pt/Co/Pt multilayer structure

Energy Technology Data Exchange (ETDEWEB)

Kalaycı, Taner, E-mail: taner.kalayci@marmara.edu.tr [Department of Physics, Marmara University, 34722, Kadıköy, Istanbul (Turkey); Deger, Caner [Department of Physics, Marmara University, 34722, Kadıköy, Istanbul (Turkey); Akbulut, Salih [Department of Physics, Gebze Technical University, 41400, Gebze, Kocaeli (Turkey); Yildiz, Fikret, E-mail: fyildiz@gtu.edu.tr [Department of Physics, Gebze Technical University, 41400, Gebze, Kocaeli (Turkey)

2017-08-15

Highlights: • Effects of Pt spacer and reference layers thickness are investigated by MOKE and FMR. • Controlling of non-collinear states in multilayered thin film systems is studied. • Micromagnetic approach is used for modeling of magnetic multilayered structure. • Magnetic parameters are determined by a simulation based on metropolis algorithm. - Abstract: In this study, effects of Pt spacer and Co reference layers thickness in [Co/Pt]{sub 6}/Pt/Co multilayer have been revealed to tailor magnetization directions in non-collinear configuration. Magneto-optic Kerr effect and ferromagnetic resonance techniques were employed to investigate magnetic properties. Bilinear coupling between [Co/Pt]{sub 6} and Co layers and anisotropy constants were determined by a micromagnetic simulation based on metropolis algorithm. 3 nm spacer causes ferromagnetic coupling while the samples have 4 and 5 nm spacer are coupled anti-ferromagneticaly. Also, tuning magnetic anisotropy of [Co/Pt]{sub 6} layer was accomplished by Co reference layer. It is revealed that controlling of non-collinear states in such systems is possible by variation of thickness of spacer and reference layers and [Co/Pt]{sub 6}/t{sub Pt}/t{sub Co} trilayer system can be used in multilayered magnetic systems.

Cerebral air embolism after arthrography of the ankle

NARCIS (Netherlands)

Müller, Marcella C. A.; Lagarde, Sjoerd M.; Germans, Menno R.; Juffermans, Nicole P.

2010-01-01

Background: The accidental migration of air from the venous circulation into the systemic arterial circulation is called paradoxical air embolism. This is a potential disastrous complication after diagnostic and surgical procedures. Arthrography has been a useful technique in joint imaging for the

3.0 T conventional hip MR and hip MR arthrography for the acetabular labral tears confirmed by arthroscopy

Energy Technology Data Exchange (ETDEWEB)

Tian, Chun-Yan [Department of Radiology, Peking University Third Hospital, 49 North Garden Road, Haidian District, Beijing 100191 (China); Wang, Jian-Quan [Department of Sports Medicine, Peking University Third Hospital, 49 North Garden Road, Haidian District, Beijing 100191,PR China (China); Zheng, Zhuo-Zhao, E-mail: zzhuozhao@aliyun.com [Department of Radiology, Peking University Third Hospital, 49 North Garden Road, Haidian District, Beijing 100191 (China); Ren, A.-Hong [Department of Radiology, Beijing Daxing Hospital, 26 West Huangcun Road, Daxing District, Beijing 102600 (China)

2014-10-15

Highlights: • MR is the preferred imaging modality for diagnosing acetabular labral tears. • The diagnostic performance of MR arthrography are superior than conventional hip MR. • The hip MR arthrography is recommended for diagnosing acetabular labral lesions. - Abstract: Objective: To evaluate the value of hip MR for diagnosing acetabular labrum tears, and to further compare the diagnostic performances of conventional MR with MR arthrography in acetabular labrum tears. Methods: 90 patients undergoing both hip MR examination and subsequent hip arthroscopy were retrospectively evaluated. Of these patients, 34 accepted both conventional MR and MR arthrography; while the other 56 only underwent conventional MR examination. All hip MR images were independently reviewed by two radiologists, and further compared with the results of hip arthroscopy. Results: 59 of 90 patients were confirmed with acetabular labral tears by hip arthroscopy and 31 without tears. The sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) of conventional MR for evaluating the acetabular labral tears were 61.0%, 77.4%, 83.7% and 51.1% (radiologist A), and 66.1%, 74.2%, 82.9% and 53.4% (radiologist B), respectively, with good consistency between the two observers (K = 0.645). The sensitivity, specificity, PPV and NPV of MR arthrography for assessing the acetabular labral tears were 90.5%, 84.6%, 90.5% and 84.6% (radiologist A), and 95.2%, 84.6%, 90.9% and 91.7% (radiologist B), respectively, with excellent good consistency between the two observers (K = 0.810). The sensitivity and NPV of MR arthrography for diagnosing the acetabular labral tears were significantly higher than those of conventional MR (both P < 0.05). Conclusion: Hip MR arthrography is a reliable evaluation modality for diagnosing the acetabular labral tears, and its diagnostic performance is superior to that of conventional MR at 3.0 T.

Chronic ankle instability: evaluation with stress radiography, CT and CT arthrography

International Nuclear Information System (INIS)

Faure, Ch.; Deplus, F.; Bochu, M.; Besse, J.L.; Moyen, B.

1997-01-01

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)

Digital subtraction arthrography in preoperative evaluation of painful total hip arthroplasty

International Nuclear Information System (INIS)

Ginai, A.Z.; Biezen, F.C. van; Kint, P.A.M.; Oei, H.Y.; Hop, W.C.J.

1996-01-01

Digital subtraction arthrograms, scintigrams and plain radiographs of 70 consecutive patients who underwent revision hip arthroplasty were scored individually and in masked fashion for the presence or absence of features indicating loosening of femoral and/or acetabular components. The operative findings acted as the gold standard. Digital subtraction arthrography was best for predicting a loose acetabular component, while no significant additional predictive value was found for plain radiographs and scintigraphy. Digital subtraction arthrography was also the most important modality for predicting a loose femoral component, while the plain radiograph was of significant additional value and scintigraphy was of no additional value on multivariate analysis. (orig./MG)

Computed tomography arthrography using a radial plane view for the detection of triangular fibrocartilage complex foveal tears.

Science.gov (United States)

Moritomo, Hisao; Arimitsu, Sayuri; Kubo, Nobuyuki; Masatomi, Takashi; Yukioka, Masao

2015-02-01

To classify triangular fibrocartilage complex (TFCC) foveal lesions on the basis of computed tomography (CT) arthrography using a radial plane view and to correlate the CT arthrography results with surgical findings. We also tested the interobserver and intra-observer reliability of the radial plane view. A total of 33 patients with a suspected TFCC foveal tear who had undergone wrist CT arthrography and subsequent surgical exploration were enrolled. We classified the configurations of TFCC foveal lesions into 5 types on the basis of CT arthrography with the radial plane view in which the image slices rotate clockwise centered on the ulnar styloid process. Sensitivity, specificity, and positive predictive values were calculated for each type of foveal lesion in CT arthrography to detect foveal tears. We determined interobserver and intra-observer agreements using kappa statistics. We also compared accuracies with the radial plane views with those with the coronal plane views. Among the tear types on CT arthrography, type 3, a roundish defect at the fovea, and type 4, a large defect at the overall ulnar insertion, had high specificity and positive predictive value for the detection of foveal tears. Specificity and positive predictive values were 90% and 89% for type 3 and 100% and 100% for type 4, respectively, whereas sensitivity was 35% for type 3 and 22% for type 4. Interobserver and intra-observer agreement was substantial and almost perfect, respectively. The radial plane view identified foveal lesion of each palmar and dorsal radioulnar ligament separately, but accuracy results with the radial plane views were not statistically different from those with the coronal plane views. Computed tomography arthrography with a radial plane view exhibited enhanced specificity and positive predictive value when a type 3 or 4 lesion was identified in the detection of a TFCC foveal tear compared with historical controls. Diagnostic II. Copyright © 2015 American Society for

Observation of low-lying resonances in the quasicontinuum of 195,196Pt and enhanced astrophysical reaction rates

Directory of Open Access Journals (Sweden)

Giacoppo F.

2015-01-01

Full Text Available An excess of strength on the low-energy tail of the giant dipole resonance recently has been observed in the γ-decay from the quasicontinuum of 195,196Pt. The nature of this phenomenon is not yet fully investigated. If this feature is present also in the γ-ray strength of the neutron-rich isotopes, it can affect the neutron-capture reactions involved in the formation of heavy-elements in stellar nucleosynthesis. The experimental level density and γ-ray strength function of 195,196Pt are presented together with preliminary calculations of the corresponding neutron-capture cross sections.

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

International Nuclear Information System (INIS)

Waldt, S.; Bruegel, M.; Mueller, D.; Holzapfel, K.; Rummeny, E.J.; Woertler, K.; Imhoff, A.B.

2007-01-01

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.)

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.)

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

International Nuclear Information System (INIS)

Kwak, Jin Young; Ha, Doo Hoe; Kim, Jeung Sook; Lee, Young Soo

2001-01-01

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

MR and MR arthrography to identify degenerative and posttraumatic diseases in the shoulder joint

International Nuclear Information System (INIS)

Lee, Shi-Uk; Lang, Philipp

2000-01-01

MR imaging provides a comprehensive evaluation of a wide spectrum of both intraarticular and extraarticular pathology of the shoulder. MR imaging enables the detection or exclusion of degenerative and posttraumatic diseases of the shoulder with a reasonable accuracy. MR arthrography is useful in the visualization of subtle anatomic details and further improves the differentiation. In this article, findings of MR imaging and MR arthrography of degenerative and posttraumatic shoulder diseases (impingement syndrome, rotator cuff tears, and glenohumeral instability) has been reviewed

Comparison of PZN-PT, PMN-PT single crystals and PZT ceramic for vibration energy harvesting

International Nuclear Information System (INIS)

Yang, Zhengbao; Zu, Jean

2016-01-01

Highlights: • Systematic analysis of PMN-PT and PZN-PT single crystals for energy harvesters. • Performance analysis and comparison under various conditions. • Discussion of the effect of the SSHI technique on single crystal energy harvesters. • Efficiency analysis in both on-resonance and off-resonance conditions. - Abstract: Vibration energy harvesting has a great potential to achieve self-powered operations for wireless sensors, wearable devices and medical electronics, and thus has attracted much attention in academia and industry. The majority of research into this subject has focused on the piezoelectric effect of synthetic materials, especially the perovskite PZT ceramics. Recently the new-generation piezoelectric materials PMN-PT and PZN-PT single crystals have gained significant interest because of their outstanding piezoelectric properties. They can be used to replace the widely-adopted PZT ceramics for improving energy harvesters’ performance substantially. However, there is little research on comparing PMN-PT and PZN-PT energy harvesters against PZT harvesters. In this paper, we present a systematic comparison between vibration energy harvesters using the PMN-PT, PZN-PT single crystals and those using the PZT ceramics. Key properties of the three materials are summarized and compared. The performance of the PMN-PT and PZN-PT energy harvesters is characterized under different conditions (beam length, resistance, frequency, excitation strength, and backward coupling effect), and is quantitatively compared with the PZT counterpart. Furthermore, the effect of the synchronized switch harvesting on inductor (SSHI) circuit on the three harvesters is discussed. The experimental results indicate that energy harvesters using the PMN-PT and PZN-PT single crystals can significantly outperform those using the PZT ceramics. This study provides a strong base for future research on high-performance energy harvesters using the new PMN-PT and PZN-PT single

Labral and cartilage abnormalities in young patients with hip pain: accuracy of 3-Tesla indirect MR arthrography

Energy Technology Data Exchange (ETDEWEB)

Petchprapa, Catherine N.; Rybak, Leon D. [NYU Langone Medical Center-Hospital for Joint Diseases, Department of Radiology, New York, NY (United States); Dunham, Kevin S.; Recht, Michael P. [NYU Langone Medical Center, Department of Radiology, New York, NY (United States); Lattanzi, Riccardo [NYU Langone Medical Center, The Bernard and Irene Schwartz Center for Biomedical Imaging, New York, NY (United States)

2015-01-15

Assess the diagnostic accuracy of 3-T indirect magnetic resonance arthrography (iMRA) for hip cartilage and labral pathology detection using arthroscopy as the reference standard and compare it to the published performance of direct magnetic resonance arthrography (dMRA). Between 2009 and 2011, 290 patients suspected of having femoroacetabular impingement underwent iMRA. Our study group consisted of 41 of these patients (17 males, mean age 35 years; 24 females, mean age 33 years) who did not have a prior history of hip surgery and who subsequently underwent arthroscopy. Two experienced musculoskeletal radiologists separately evaluated the randomized and anonymized studies for the presence and quadrant location of labral and cartilage pathology. These recorded data were compared to arthroscopic reports. Forty-one patients had labral pathology, 34 patients had acetabular and 5 patients had femoral cartilage pathology at arthroscopy. Sensitivity, specificity, accuracy, negative- and positive-predictive values for labral lesion detection were respectively 98, 99, 99, 99 and 98 %; for acetabular cartilage lesion detection they were 69, 98, 89, 87 and 95 %; for femoral cartilage lesion detection they were 69, 95, 93 and 39 %. Sensitivities of iMRA by quadrant (anteroinferior, anterosuperior, posteroinferior, posterosuperior) for the labrum were 100.0, 95.0, NA and 85.7 %, for acetabular cartilage were NA, 58.8, NA and 39.5 % and for femoral cartilage were 50.0, 33.3, 75.0 and 75.0 %. NA indicates results not available because of the absence of findings in those quadrants. Specificities of iMRA by quadrant (anteroinferior, anterosuperior, posteroinferior, posterosuperior) for the labrum (95.0, 100.0, 95.1, 67.5 %), acetabular (100.0, 85.7, 92.6, 79.5 %) and femoral cartilage (100.0, 94.7, 96.2, 85.9 %). iMRA at 3 T is accurate in detecting labral pathology suggesting that it is a viable alternative to dMRA. (orig.)

High-resolution magnetic resonance imaging of rotator cuff tears using a microscopy coil. Noninvasive detection without intraarticular contrast material

International Nuclear Information System (INIS)

Hitachi, Shin; Takase, Kei; Higano, Shuichi; Takahashi, Shoki; Tanaka, Minoru; Tojo, Yuichi; Tabata, Shiro; Majima, Kazuhiro

2011-01-01

The aim of this study was to evaluate the feasibility of high-resolution magnetic resonance imaging (MRI) using a microscopy coil for the diagnosis of rotator cuff tears by comparing the method to conventional MRI and MRI arthrography. A total of 68 shoulders were prospectively studied using a 1.5-T MRI unit. Conventional MRI scans were obtained with a surface coil and high-resolution MRI scans with a microscopy coil. MRI arthrography was performed in 28 shoulders using a surface coil. MRI evaluation of tears of rotator cuff tendons was compared with arthroscopic findings and surgical results. The surgery revealed 40 full-thickness tears, 13 partial-thickness tears, and 15 intact cuffs. In all, 35 (88%) full-thickness tears were correctly diagnosed on conventional MRI and 40 (100%) on high-resolution MRI. MR arthrography delineated 11 of 12 (92%) full-thickness tears. Altogether, 5 (38%) of the partial-thickness tears were detected on conventional MRI, and 12 (92%) were clearly demonstrated on high-resolution MRI. MRI arthrography depicted three (60%) of five partial-thickness tears. High-resolution MRI showed higher sensitivity than conventional MRI (P<0.05) and had values equivalent to those of MRI arthrography for diagnosing partial-thickness tears. High-resolution MRI with a microscopy coil is a feasible, noninvasive technique for diagnosing rotator cuff tears. (author)

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

International Nuclear Information System (INIS)

Lee, Whal; Chung, Jin-Wook; Kang, Heung-Sik; Hong, Sung-Hwan; Choi, Ja-Young; Kim, Ho-Sung; Kim, Seok-Jung; Kim, Hyung-Ho

2004-01-01

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

Radiographic anatomy and technique for arthrography of the cubital joint in clinically normal dogs

International Nuclear Information System (INIS)

Lowry, J.E.; Carpenter, L.G.; Park, R.D.; Steyn, P.F.; Schwarz, P.D.

1993-01-01

A technique for arthrography of the cubital joint in clinically normal large-breed dogs was developed with the objective of improving visualization of the articular margin of the medial coronoid process. A lateral approach to the cubital joint for injection of contrast medium was selected. Arthrography of 24 cubital joints was performed by using 14 dogs. Twelve combinations of iodinated contrast medium, consisting of various concentrations (3) and volumes (4), were used. Two sets of arthrograms for each of the 12 combinations of contrast medium were obtained. Five radiographic views were used for each set. All arthrograms were examined by 3 evaluators, and each articular surface received a numerical rating for how well it could be seen in each view. Results of the evaluation indicated that low volumes of contrast medium were preferable to high volumes, with 2 ml providing the best visualization. Concentration of iodine seemed less important than did volume. The numerical ratings also indicated that the articular margin of the coronoid process was clearly observed a maximum of only 24% of the time on a slightly supinated mediolateral projection. The articular margins of the head of the radius, trochlea humeri, and trochlear notch were well visualized > 90% of the time. Arthrography of the cubital joint was technically easy to perform, and complications were not encountered, but arthrographic anatomy of the cubital joint is complex. Potential uses for arthrography of the cubital joint include diagnosis of osteochondrosis, intraarticular fragments, and joint capsule ruptures

Double-contrast arthrography in recurrent dislocation of the shoulder

International Nuclear Information System (INIS)

Faletti, C.; Vassoney, P.F.; Indemini, E.; Clerico, P.

1988-01-01

One hundred and ninety-three shoulder arthrographies were performed between 1979 and 1985 on patients affected by recurrent dislocations. The diagnostic doubt was cleared up in 162 cases (83%). Athrographic diagnosis was confirmed by pathological findings in 92% of the patients who underwent surgery. The double-contrast technique under local anaesthesia with anterior access is suggested, since it allows several arthrograms in different projections. Thus, an analytic study of the articular damage can be carried out. The patterns of each projection are briefly shown. Revision of case histories points out that: a) the use of arthrography should always be assessed on a clinical-radiological basis for each patients; b) there is no doubt as to the usefulness of this examination as a direct means of exploration, as far as the articular damage is concerned, not only as an aid to future surgery, but also in the follow-up of the results of the treatment in the long run

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

Energy Technology Data Exchange (ETDEWEB)

Kim, Sang-Il [Department of Materials Science and Engineering, Korea University, Seoul, 136-713 (Korea, Republic of); Spin Engineering Physics Team, Division of Scientific Instrumentation, Korea Basic Science Institute, Daejeon, 305-806 (Korea, Republic of); Seo, Min-Su [Spin Engineering Physics Team, Division of Scientific Instrumentation, Korea Basic Science Institute, Daejeon, 305-806 (Korea, Republic of); Choi, Yeon Suk, E-mail: ychoi@kbsi.re.kr [Spin Engineering Physics Team, Division of Scientific Instrumentation, Korea Basic Science Institute, Daejeon, 305-806 (Korea, Republic of); Park, Seung-Young, E-mail: parksy@kbsi.re.kr [Spin Engineering Physics Team, Division of Scientific Instrumentation, Korea Basic Science Institute, Daejeon, 305-806 (Korea, Republic of)

2017-01-01

Magnetic field (H) sweeping direction dependences of the mixed voltage V{sub mix} 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 V{sub ISH} (symmetric) excluding the SRE (antisymmetric component) was unavoidably separated from the fitting curve of V{sub mix} (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 V{sub ISH} (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. - Highlights: • Hysteretic behavior of ferromagnetic resonance spectra in the CoFeB/Pt sample. • Hysteretic behavior of inverse-spin Hall effect voltage in the CoFeB/Pt sample. • Proportion of inverse spin-Hall effect voltage can be determined by the cavity mode. • The hysteretic behavior arise from the unsaturated magnetization limit. • The well-defined spin Hall angle which consider a hysteresis can be obtained.

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

Energy Technology Data Exchange (ETDEWEB)

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.)

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

International Nuclear Information System (INIS)

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

1985-01-01

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

Bursae and abscess cavities communicating with the hip: diagnosis using arthrography and CT

International Nuclear Information System (INIS)

Steinbach, L.S.; Schneider, R.; Goldman, A.B.; Kazam, E.; Ranawat, C.S.; Ghelman, B.

1985-01-01

Bursae or abscess cavities communicating with the hip joint were demonstrated by hip arthrography or by computed tomography (CT) in 40 cases. The bursae or abscess cavities were associated with underlying abnormalities in the hip, including painful hip prostheses, infection, and inflammatory or degenerative arthritis. Symptoms may be produced directly as a result of infection or indirectly as a result of inflammation or pressure on adjacent structures. Hip arthrography can confirm a diagnosis of bursae and abscess cavities communicating with the hip joint in patients with hip pain or soft-tissue masses around the groin. Differentiation of enlarged bursae from other abnormalities is important to avoid unnecessary or incorrect surgery

Direct MR Arthrography of the wrist in comparison with Arthroscopy: A prospective study on 125 patients; Direkte MR-Arthrographie des Handgelenks im Vergleich zur Arthroskopie: Eine prospektive Studie an 125 Patienten

Energy Technology Data Exchange (ETDEWEB)

Schmitt, R.; Christopoulos, G.; Coblenz, G.; Froehner, S. [Institut fuer Diagnostische und Interventionelle Radiologie der Herz- und Gefaessklinik GmbH, Bad Neustadt an der Saale (Germany); Meier, R.; Lanz, U.; Krimmer, H. [Klinik fuer Handchirurgie GmbH, Bad Neustadt an der Saale (Germany)

2003-07-01

Objective: In literature the diagnostic value of MRI for detecting lesions of the carpal ligaments and the TFCC is judged controversially. The aim of the following study is to determine the diagnostic accuracy of direct MR arthrography for depicting and staging of intraarticular lesions of the wrist. Material and methods: One day before undergoing arthroscopy, 125 patients suffering from wrist pain were examined with direct MR arthrography in a prospective and blinded study. A mixture of contrast medium (iodine-containing contrast medium and gadopentetate in relation 200:1) was injected into both radiocarpal and midcarpal joints. The following sequences were acquired on a 1.5T scanner: coronal T1-weighted SE, coronal fat-saturated T1-weighted SE, coronal T1-/T2*-DESS-3D, and sagittal T2*-weighted MEDIC. MRI results were compared with arthroscopic findings using statistical analysis (SEN=sensitivity, SPE=specificity, PPV=positive predictive value, NPV=negative predictive value, ACC=accuracy). Results: In comparison to arthroscopy as the accepted diagnostic gold standard, the following results were found for MR arthrography. Detection of TFCC lesions: SEN 97.1%, SPE 96.4%, PPV 97.1%, NPV 96.4%, ACC 96.8%. Detection of complete tears of the scapholunate ligament: SEN 91.7%, SPE 100%, PPV 100%, NPV 99.1%, ACC 99.2%. Detection of partial tears: SEN 62.5%, SPE 100%, PPV 100%, NPV 94.8%, ACC 95.2%. Detection of cartilage defects: SEN 84.2%, SPE 96.2%, PPV 80%, NPV 97.1%, ACC 94.4%. In total, only three lesions of the lunotriquetral ligament were present. Conclusion: Direct MR arthrographic imaging is well suited for detecting intraarticular lesions of the wrist. The presented diagnostic results of MR arthrography are superior to the results of unenhanced MRI reported in the literature. Direct MR arthrography as a reliable diagnostic tool is strongly recommended if lesions of the scapholunate ligament and the triangular fibrocartilage complex are suspected. In contrast, an

Labral-Ligamentous Complex of the Shoulder. Evaluation with double oblique axial MR arthrography. Technical Note

International Nuclear Information System (INIS)

Sasaki, Taisuke; Saito, Y.; Yodono, H.; Prado, G.L.M.; Miura, H.; Itabashi, Y.; Ishibashi, Y.

2003-01-01

Purpose: To assess the ability of double oblique axial (DOA) MR arthrography in evaluating labral-ligamentous complex compared with conventional axial (CA) MR arthrography. Material and Methods: MR arthrography of 51 shoulders, subsequently examined with arthroscopy, were retrospectively reviewed. DOA imaging was performed in all 51 shoulders and both DOA and CA imaging in 37 using a 1.5 T unit with gradient recalled-echo T2*-weighted sequences. DOA imaging was performed using perpendicular planes to the long axis of the glenoid fossa obtained by an oblique sagittal scout image. We compared the ability of DOA with that of CA MR arthrography to assess labral injuries and to demonstrate the whole length of the anterior band of the inferior glenohumeral ligament (AIGHL), which were shown to be intact by arthroscopy. Results: For anterior labral injuries, sensitivity and specificity were 87% and 93% with CA, and 94% and 100% with DOA imaging, respectively. For posterior labral injuries, sensitivity and specificity were 47% and 100% with CA, and 79% and 96% with DOA imaging, respectively. There were no statistically significant differences between CA and DOA images, except for the ability to diagnose posterior labral injuries, where DOA imaging had a significant superior sensitivity (p = 0.0327). DOA images also demonstrated the whole length of the intact AIGHL in 10 of 11 shoulders, while CA imaging showed this in only 3 of 11. Conclusion: DOA imaging was equal or better than CA imaging for evaluating the labral-ligamentous complex

Wrist Traction During MR Arthrography Improves Detection of Triangular Fibrocartilage Complex and Intrinsic Ligament Tears and Visibility of Articular Cartilage.

Science.gov (United States)

Lee, Ryan K L; Griffith, James F; Ng, Alex W H; Nung, Ryan C H; Yeung, David K W

2016-01-01

The purpose of this study was to assess the effects of traction during MR arthrography of the wrist on joint space widening, cartilage visibility, and detection of tears of the triangular fibrocartilage complex (TFCC) and intrinsic ligaments. A prospective study included 40 wrists in 39 patients (25 men, 14 women; mean age, 35 years). MR arthrography was performed with a 3-T MRI system with and without axial traction. Two radiologists independently measured wrist and carpal joint space widths and semiquantitatively graded articular cartilage visibility. Using conventional arthrography as the reference standard and working in consensus, they assessed for the presence of tears of the TFCC, lunotriquetral ligament (LTL), and scapholunate ligament (SLL). Visibility of a tear before traction was compared with visibility after traction. With traction, all joint spaces in the wrist and carpus were significantly widened (change, 0.15-1.01 mm; all p < 0.006). Subjective cartilage visibility of all joint spaces improved after traction (all p ≤ 0.048) except for that of the radioscaphoid space, which was well visualized even before traction. Conventional arthrography depicted 24 TFCC tears, seven LTL tears, and three SLL tears. The accuracy of tear detection improved after traction for the TFCC (98% after traction vs 83% before traction), the LTL (100% vs 88%), and the SLL (100% vs 95%). Tear visibility improved after traction for 54% of TFCC tears, 71% of LTL tears, and 66% of SLL tears. Wrist MR arthrography with axial traction significantly improved the visibility of articular cartilage and the detection and visibility of tears of the TFCC and intrinsic ligaments. The results favor more widespread use of traction during MR arthrography of the wrist.

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.)

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

International Nuclear Information System (INIS)

Jung, Joon-Yong; Jee, Won-Hee; Chun, Chang-Woo; Kim, Yang-Soo

2017-01-01

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.)

Shoulder-Mounted Robot for MRI-guided arthrography: Accuracy and mounting study.

Science.gov (United States)

Monfaredi, R; Wilson, E; Sze, R; Sharma, K; Azizi, B; Iordachita, I; Cleary, K

2015-08-01

A new version of our compact and lightweight patient-mounted MRI-compatible 4 degree-of-freedom (DOF) robot for MRI-guided arthrography procedures is introduced. This robot could convert the traditional two-stage arthrography procedure (fluoroscopy-guided needle insertion followed by a diagnostic MRI scan) to a one-stage procedure, all in the MRI suite. The results of a recent accuracy study are reported. A new mounting technique is proposed and the mounting stability is investigated using optical and electromagnetic tracking on an anthropomorphic phantom. Five volunteer subjects including 2 radiologists were asked to conduct needle insertion in 4 different random positions and orientations within the robot's workspace and the displacement of the base of the robot was investigated during robot motion and needle insertion. Experimental results show that the proposed mounting method is stable and promising for clinical application.

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

International Nuclear Information System (INIS)

De Filippo, M.; Bertellini, A.; Sverzellati, N.; Pogliacomi, F.; Costantino, C.; Vitale, M.; Zappia, M.; Corradi, D.; Garlaschi, G.; Zompatori, M.

2008-01-01

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 (κ=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

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

MR arthrography of the knee

International Nuclear Information System (INIS)

Kramer, J. Jr.; Engel, A. Jr.; Stiglbauer, R.; Prayer, L. Jr.; Hajek, P. Jr.; Imhof, H.

1991-01-01

This paper reports on MR imaging which has gained increasing importance as a diagnostic instrument in orthopedics. The key to joint diagnostics - the evaluation of hyaline articular cartilage - however, has not been touched sufficiently by this development. Fundamental studies were done and 140 patients were examined with MR imaging after intraarticular administration of contrast agent. Hyaline cartilage, cruciate ligaments, and menisci were assessed before and after injection of a 2-mmol/L Gd-DTPA solution, and the results were compared with those of arthroscopy/arthrotomy. MR arthrography provided superior image quality compared with plain MR imaging. This resulted in an improved delineation of intraarticular structures, especially of cartilage defects

Miniature PT Cryocooler Activated by Resonant Piezoelectric Compressor and Passive Warm Expander

Science.gov (United States)

Sobol, S.; Grossman, G.

2017-12-01

A novel type of PZT-based compressor operating at mechanical resonance, suitable for pneumatically-driven Stirling-type cryocoolers, was presented at CEC-ICMC 2015. The detailed concept, analytical model and the test results on the preliminary prototype were reported earlier and presented at ICC17. Despite some mismatch between the impedances and insufficient structural stiffness, this compressor demonstrated the feasibility to drive our miniature Pulse Tube cryocooler MTSa, operating at 103 Hz and requiring an average PV power of 11 W, filling pressure of 40 Bar and a pressure ratio of 1.3. At ICC19 the prototype of a miniature passive warm expander (WE) was presented. The WE mechanism included a phase shifting piston suspended on a silicone diaphragm, a mass element, and a viscous damping system. Several technical drawbacks prevented perfect matching between the WE and MTSa; however, the presented prototype proved the ability to create any flow-to-pressure phase appropriate for a PT cryocooler. This paper concentrates on integration of the MTSa cryocooler with the recently modified PZT compressor operating at corrected mechanical resonance and the modified WE, which was also updated recently to match the MTSa requirements.

Comparison of radiographic and radionuclide hip arthrography in determination of femoral component loosening of hip arthroplasties

International Nuclear Information System (INIS)

Capello, W.N.; Uri, B.G.; Wellman, H.N.; Robb, J.A.; Stiver, P.L.

1985-01-01

Radiographic examination of a patient experiencing pain following total hip arthroplasty is an important step in the systematic approach to evaluating component loosening, even though the information yielded is often equivocal and nondiagnostic in assessing component loosening. The radiographic criteria for loosening are especially difficult to assess following revision surgery, for radiolucent lines frequently exist at the bone-cement interface immediately following implantation. The advent of noncemented hip prostheses poses another problem: the routinely noted disruption of bone-cement of prosthesis-cement interfaces is not present with uncemented prostheses. As the criteria for loosening of the noncemented prostheses are still evolving, plain radiographic examination is frequently nondiagnostic. Femoral component loosening is difficult to detect with standard contrast arthrography because the bone, metal, surrounding radiopaque cement and contrast agents have similar or identical radiographic appearances. In contrast arthrography, if the prosthesis is loose the injected agent opacifies the radiolucent zone encircling the prosthesis or cement mangle. Because of the similarity in the appearances of these agents and the surrounding structures on x-ray films, interpretation is difficult. The inclusion of subtraction techniques in routine contrast arthrography has improved its accuracy; however, these techniques require special equipment and demand precise patient positioning. The purpose of this study is to introduce a new form of hip arthrography using a radionuclide agent in place of the contrast agent. A comparison of the results using these two techniques is presented

Incidence of greater trochanteric pain syndrome in patients suspected for femoroacetabular impingement evaluated using magnetic resonance arthrography of the hip.

Science.gov (United States)

Pozzi, Grazia; Lanza, Ezio; Parra, Cleber Garcia; Merli, Ilaria; Sconfienza, Luca Maria; Zerbi, Alberto

2017-03-01

We evaluated the incidence of greater trochanter pain syndrome (GTPS) in patients who underwent magnetic resonance arthrography (MRA) of the hip for a suspected femoroacetabular impingement (FAI) syndrome. Hip MRA performed at our institution (3/2012-1/2014) were reviewed. The absence/presence of FAI (cam, pincer, and mixed) was noted. GTPS diagnosis was based on gluteus medius/minimus tendinopathy/tears, trochanteric bursitis, fascia lata thickening, and trochanter bone oedema/erosion. Subgroup analysis for age (under/over 40 years) and FAI type (cam, pincer, and mixed) was also performed. N = 189 patients were included (n = 125 males; age 39 ± 12 years). FAI was diagnosed in n = 133 (70, 4%): cam type, n = 85 (63, 9%); pincer type, n = 22 (16, 6%); and mixed type, n = 26 (19, 5%). N = 72 patients (38.1%) had tendinopathy, n = 14 (7.4%) had trochanter erosion, n = 31 (16.4%) had bursitis, n = 4 had bone oedema (2.1%), and n = 3 (1.6%) had fascia lata thickening, resulting in GTPS diagnosis in n = 74 patients (39.2%). The association of normal hip morphology/GTPS was significantly higher (P = 0.023) than that of FAI/GTPS. Under 40 years, GTPS incidence was higher in patients with normal hip and pincer-type FAI (P = 0.028). Over 40 years, no difference between patients with/without FAI (P = 0.119) was seen. GTPS was more frequently observed in patients with normal hip morphology than in patients with FAI, particularly in patients under 40.

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

International Nuclear Information System (INIS)

Birchall, Christopher; Schomerus, Henning

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. This article is part of a special issue of Journal of Physics A: Mathematical and Theoretical devoted to ‘Quantum physics with non-Hermitian operators’. (paper)

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

International Nuclear Information System (INIS)

Daenen, B.R.; Ferrara, M.A.; Marcelis, S.; Dondelinger, R.F.

1998-01-01

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.)

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.

Dislocation of the temporomandibular joint meniscus: contrast arthrography vs. computed tomography

International Nuclear Information System (INIS)

Thompson, J.R.; Christiansen, E.; Sauser, D.; Hasso, A.N.; Hinshaw, D.B. Jr.

1985-01-01

A prospective study to determine the accuracy of computed tomography (CT) for the diagnosis of dislocation of the temporomandibular joint (TMJ) meniscus was made by performing both CT and contrast arthrography on 18 joints suspected of meniscus dislocation. Arthography rather than surgery was chosen as the quality standard for comparing CT findings, as not all patients undergoing the studies underwent surgery. The results of each test were reported independently by the radiologist who obtained either all of the arthograms or all of the CT scans. For dislocation of the meniscus, there were excellent agreement between the two methods. CT seems to be nearly as accurate as arthrography for showing meniscus dislocation, is performed with lower x-ray exposure, and is noninvasive. Arthrograpy discloses more detailed information about the joint meniscus, such as perforation and maceration, and should continue to be used when this kind of information is clinically important

The reactions ππ → ππ and γγ → ππ χPT with an isosinglet scalar resonance

Energy Technology Data Exchange (ETDEWEB)

Thapaliya, Arbin [Franklin College, Department of Chemistry and Physics, Franklin, IN (United States); Ohio University, Institute of Nuclear and Particle Physics and Department of Physics and Astronomy, Athens, OH (United States); Phillips, Daniel R. [Ohio University, Institute of Nuclear and Particle Physics and Department of Physics and Astronomy, Athens, OH (United States)

2017-10-15

The lowest-lying resonance in the QCD spectrum is the 0{sup ++} isoscalar σ-meson, also known as the f{sub 0}(500). We augment SU(2) chiral perturbation theory (χPT) by including the σ-meson as an additional explicit degree of freedom, as proposed by Soto, Talavera, and Tarrus and others. In this effective field theory, denoted χPT{sub S}, the σ-meson's well-established mass and decay width are not sufficient to properly renormalize its self energy. At O(p{sup 4}) another low-energy constant appears in the dressed σ-meson propagator; we adjust it so that the isoscalar pion-pion scattering length is also reproduced. We compare the resulting amplitudes for the ππ → ππ and γγ → ππ reactions to data from threshold through the energies at which the σ-meson resonance affects observables. The leading-order (LO) ππ amplitude reproduces the σ-meson pole position, the isoscalar ππ scattering lengths and ππ scattering and γγ → ππ data up to √(s) ∼ 0.5 GeV. It also yields a γγ → ππ amplitude that obeys the Ward identity. The value obtained for the π{sup 0} polarizability is, however, only slightly larger than that obtained in standard χPT. (orig.)

Direct MR Arthrography of the wrist in comparison with Arthroscopy: A prospective study on 125 patients

International Nuclear Information System (INIS)

Schmitt, R.; Christopoulos, G.; Coblenz, G.; Froehner, S.; Meier, R.; Lanz, U.; Krimmer, H.

2003-01-01

Objective: In literature the diagnostic value of MRI for detecting lesions of the carpal ligaments and the TFCC is judged controversially. The aim of the following study is to determine the diagnostic accuracy of direct MR arthrography for depicting and staging of intraarticular lesions of the wrist. Material and methods: One day before undergoing arthroscopy, 125 patients suffering from wrist pain were examined with direct MR arthrography in a prospective and blinded study. A mixture of contrast medium (iodine-containing contrast medium and gadopentetate in relation 200:1) was injected into both radiocarpal and midcarpal joints. The following sequences were acquired on a 1.5T scanner: coronal T1-weighted SE, coronal fat-saturated T1-weighted SE, coronal T1-/T2*-DESS-3D, and sagittal T2*-weighted MEDIC. MRI results were compared with arthroscopic findings using statistical analysis (SEN=sensitivity, SPE=specificity, PPV=positive predictive value, NPV=negative predictive value, ACC=accuracy). Results: In comparison to arthroscopy as the accepted diagnostic gold standard, the following results were found for MR arthrography. Detection of TFCC lesions: SEN 97.1%, SPE 96.4%, PPV 97.1%, NPV 96.4%, ACC 96.8%. Detection of complete tears of the scapholunate ligament: SEN 91.7%, SPE 100%, PPV 100%, NPV 99.1%, ACC 99.2%. Detection of partial tears: SEN 62.5%, SPE 100%, PPV 100%, NPV 94.8%, ACC 95.2%. Detection of cartilage defects: SEN 84.2%, SPE 96.2%, PPV 80%, NPV 97.1%, ACC 94.4%. In total, only three lesions of the lunotriquetral ligament were present. Conclusion: Direct MR arthrographic imaging is well suited for detecting intraarticular lesions of the wrist. The presented diagnostic results of MR arthrography are superior to the results of unenhanced MRI reported in the literature. Direct MR arthrography as a reliable diagnostic tool is strongly recommended if lesions of the scapholunate ligament and the triangular fibrocartilage complex are suspected. In contrast, an

Is sonography performed by the rheumatologist as useful as arthrography executed by the radiologist for the assessment of full thickness rotator cuff tears?

NARCIS (Netherlands)

Swen, W. A.; Jacobs, J. W.; Neve, W. C.; Bal, D.; Bijlsma, J. W.

1998-01-01

Sonography and arthrography are techniques used to detect rotator cuff tears (RCT). The diagnostic value of sonography executed by a rheumatologist versus that of arthrography performed by a radiologist for assessment of RCT was investigated among patients with unilateral chronic shoulder complaints

Arthrography of the biceps tendon

International Nuclear Information System (INIS)

Ahovuo, J.; Linden, H.; Hovi, I.; Paavolainen, P.; Bjoerkenheim, J.M.

1988-01-01

The purpose of this study was to analyse the factors having an influence on the arthrographic imaging of the biceps tendon. The study comprised 174 patients suffering from chronic shoulder pain. They underwent conventional shoulder arthrography with sodium meglumine metrizoate or metrizamide as a contrast medium. In the patients with a full-thickness tear of the rotator cuff, the biceps tendon sheath failed to fill with contrast medium more often than in those with an intact tendinous cuff. Metrizamide filled the biceps tendon sheath more readily than sodium meglumine metrizoate in patients with a full-thickness tear of the ortator cuff. The volume of the contrast medium injected had no influence on the imaging of the biceps tendon. (orig.)

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

International Nuclear Information System (INIS)

Spick, Claudio; Szolar, Dieter H.M.; Reittner, Pia; Preidler, Klaus W.; Tillich, Manfred

2014-01-01

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

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

Energy Technology Data Exchange (ETDEWEB)

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

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

Accuracy of 3-Tesla MR and MR arthrography in diagnosis of meniscal retear in the post-operative knee

Energy Technology Data Exchange (ETDEWEB)

Magee, Thomas [NSI, Merritt Island, FL (United States); University of Central Florida School of Medicine, Orlando, FL (United States)

2014-08-15

This study assesses the accuracy of 3-Tesla (3-T) conventional MR imaging, 3-T MR arthrography, and the combined use of conventional MR and MR arthrography in the diagnosis of meniscal retears as compared with arthroscopy. The study also assess whether there are false-negative cases in which injected contrast does not extend into the meniscus despite a meniscal retear being seen on arthroscopy. One hundred consecutive knee MR arthrograms performed on patients with previous knee surgery were reviewed retrospectively. 3-T conventional MR imaging, 3-T MR arthrography, and the combined use of conventional MR and MR arthrography were assessed for meniscal retears as compared with arthroscopy. The criterion used to diagnose a meniscal retear on MR arthrogram was injected contrast tracking into the meniscus. All patients underwent second-look arthroscopy. Seventy-four patients had conventional MR findings consistent with a meniscal retear. In 83 of the 100 patients, intraarticular contrast helped in demonstrating a retear. In ten patients, there were MR findings consistent with a meniscal retear despite intra-articular contrast not tracking into the meniscus. Ninety-four of the 100 patients had meniscal retears on second-look arthroscopy. Three-Tesla conventional MR examination was 78 % sensitive and 75 % specific, MR arthrogram examination was 88 % sensitive and 100 % specific, and the combined use of MR and MR arthrogram imaging was 98 % sensitive and 75 % specific in the diagnosis of a meniscal retear. The combined use of 3-T MR and MR arthrography allows for high sensitivity and specificity in meniscal retear detection. In some patients, intraarticular contrast will not track into a meniscal retear. When MR findings are consistent with a meniscal retear but contrast does not extend into the meniscus, a meniscal retear is likely. (orig.)

Radiologic findings of double contrast knee arthrography

International Nuclear Information System (INIS)

Choi, Hye Ran; Ahn, Byeong Yeob; Kim, Mi Young; Lee, So Hyun; Suh, Chang Hae; Chung, Won Kyun

1990-01-01

The double contrast arthrography of the knee is a highly accurate diagnostic modality in wide rage of the clinical disorders of the knee. It allows radiological assessment of the menisci, the articular cartilages, the synovium and the ligaments. The double contrast knee arthrography was performed in 356 cases at Inha hospital for about 3 years from June 1986 to June 1989. Among them, 115 cases were abnormal, and were analyzed clinically and radiologically with the back ground of the operative finding. The results were as follows ; 1. Of the 115 cases, male were 77 and female 38. Male exceeds female in the ratio of 2 : 1. 2. The age group of 20 - 39 years was commonly involved (60%). 3. The right knee was more commonly involved than the left and the medial meniscus tear was more common (61%). The posterior horn of the meniscus was more frequently torn than the other parts of the meniscus (42%). 4. The incidence of the bucket-handle tear was the most frequent (33%). 5. The cases of the popliteal cyst were 16 (13.9%), and the combined meniscus tears were in 4 cases (25%). 6. The numbers of the discoid meniscus were 9 (7.8%), and all were present in the lateral meniscus, and combined tears were in 4 cases (44.4%). 7. The diagnostic accuracy of the double contrast knee arthrogram was 82.7% compared with operative finding. The false positive examination were 17.3%

Role of arthrography in the management of dysplasia epiphysealis hemimelica

Energy Technology Data Exchange (ETDEWEB)

Ho, A.M.W.; Blane, C.E.; Kling, T.F. Jr.

1986-03-01

Dysplasia epiphysealis hemimelica can be diagnosed on plain radiographs of the affected areas. However, double contrast arthrography in three new cases provided additional information. The cartilaginous portions of the lesion at the articular surface of the bone were precisely demonstrated, aiding the orthopedic surgeon in deciding which patients should have surgery and planning the extent of operation necessary.

Bilateral three-compartment wrist arthrography in patients with unilateral wrist pain: findings and implications for management

International Nuclear Information System (INIS)

Romaniuk, C.S.; Butt, W.P.; Coral, A.

1995-01-01

Bilateral three-compartment wrist arthrography was performed in 30 patients with unilateral post-traumatic wrist pain to assess the incidence of bilateral findings. The mean age of patients was 30 (range 18-55) years. Thirty-three percent of patients were normal bilaterally, 30% had unilateral communication in the symptomatic wrist, 30% had communications in both the symptomatic and asymptomatic wrists and 7% had communication in the asymptomatic wrist only. Unilateral three-compartment wrist arthrography is not recommended in the assessment of unilateral post-traumatic wrist pain; no advantage of three-compartment injection over radiocarpal injection alone was shown. (orig.)

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

International Nuclear Information System (INIS)

Mostafa, A.; Gokan, Takehiko; Munechika, Hirotsugu; Ogawa, Takashi; El-Feky, A.A.

2001-01-01

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)

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.)

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

International Nuclear Information System (INIS)

Guggenberger, Roman; Ulbrich, Erika J.; Kaelin, Pascal; Pfammatter, Thomas; Alkadhi, Hatem; Andreisek, Gustav; Dietrich, Tobias J.; Scholz, Rosemarie; Koehler, Christoph; Elsaesser, Thilo; Le Corroller, Thomas

2017-01-01

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.)

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.)

Diagnostic value of US, CT arthrography, and 0.5-T MR imaging of lesions of the biceps tendon

International Nuclear Information System (INIS)

Saez, F.; Elizagaray, E.; Pena, J.M.; Ferrero, A.; Azkuna, I.; Larrea, L.

1990-01-01

This paper evaluates the role of US, CT-arthrography, and MR imaging in lesions in the tendon of the long head of the biceps brachii and bicipital groove. One hundred fifty-four patients with painful shoulder were prospectively studied by means of US and axial CT-arthrography, and 45 of them were also examined with 0.5-T MR imaging. Fifty-three (34.4%) patients showed biceps tendon or bicipital groove abnormalities; including 34 bicipital groove bone spurs, 31 cases of tendinitis, eight intraarticular ruptures, four subluxations, and eight medial dislocations

Determination of intrinsic spin Hall angle in Pt

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Wang, Yi; Deorani, Praveen; Qiu, Xuepeng; Kwon, Jae Hyun; Yang, Hyunsoo, E-mail: eleyang@nus.edu.sg [Department of Electrical and Computer Engineering, National University of Singapore, 117576 (Singapore)

2014-10-13

The spin Hall angle in Pt is evaluated in Pt/NiFe bilayers by spin torque ferromagnetic resonance measurements and is found to increase with increasing the NiFe thickness. To extract the intrinsic spin Hall angle in Pt by estimating the total spin current injected into NiFe from Pt, the NiFe thickness dependent measurements are performed and the spin diffusion in the NiFe layer is taken into account. The intrinsic spin Hall angle of Pt is determined to be 0.068 at room temperature and is found to be almost constant in the temperature range of 13–300 K.

Determination of intrinsic spin Hall angle in Pt

International Nuclear Information System (INIS)

Wang, Yi; Deorani, Praveen; Qiu, Xuepeng; Kwon, Jae Hyun; Yang, Hyunsoo

2014-01-01

The spin Hall angle in Pt is evaluated in Pt/NiFe bilayers by spin torque ferromagnetic resonance measurements and is found to increase with increasing the NiFe thickness. To extract the intrinsic spin Hall angle in Pt by estimating the total spin current injected into NiFe from Pt, the NiFe thickness dependent measurements are performed and the spin diffusion in the NiFe layer is taken into account. The intrinsic spin Hall angle of Pt is determined to be 0.068 at room temperature and is found to be almost constant in the temperature range of 13–300 K.

Gamma Radiolytic Formation of Alloyed Ag-Pt Nanocolloids

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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.

Optimization of the Contrast Mixture Ratio for Simultaneous Direct MR and CT Arthrography: an in Vitro Study

International Nuclear Information System (INIS)

Choi, Ja Young; Hong, Sung Hwan; Kim, Na Ra; Jun, Woo Sun; Moon, Sung Gyu; Kang, Heung Sik; Lee, Joon Woo; Choi, Jung Ah

2008-01-01

This study was designed to determine the optimal mixture ratio of gadolinium and iodinated contrast agent for simultaneous direct MR arthrography and CT arthrography. An in vitro study was performed utilizing mixtures of gadolinium at six different concentrations (0.625, 1.25, 2.5, 5.0, 10 and 20 mmol/L) and iodinated contrast agent at seven different concentrations (0, 12.5, 25, 37.5, 50, 75 and 92-99.9%). These mixtures were placed in tissue culture plates, and were then imaged with CT and MR (with T1-weighted sequences, proton-density sequences and T2-weighted sequences). CT numbers and signal intensities were measured. Pearson's correlation coefficients were used to assess the correlations between the gadolinium/iodinated contrast agent mixtures and the CT numbers/MR signal intensities. Scatter diagrams were plotted for all gadolinium/iodinated contrast agent combinations and two radiologists in consensus identified the mixtures that yielded the optimal CT numbers and MR signal intensities. The CT numbers showed significant correlation with iodinated contrast concentrations (r = 0.976, p < 0.001), whereas the signal intensities as measured on MR images showed a significant correlation with both gadolinium and iodinated contrast agent concentrations (r = -484 to -0.719, p < 0.001). A review of the CT and MR images, graphs, and scatter diagram of 42 combinations of the contrast agent showed that a concentration of 1.25 mmol/L gadolinium and 25% iodinated contrast agent was the best combination for simultaneous CT and MR imaging. A mixture of 1.25 mmol/L gadolinium and 25% iodinated contrast agent was found to be optimal for simultaneous direct MR arthrography and CT arthrography

Multi-detector CT knee arthrography - initial experience

International Nuclear Information System (INIS)

Thomson, J.M.Z.; Fallon, M.; Breidahl, W.H.

2002-01-01

Full text: Traditional plain film arthrography can achieve reasonable accuracy and is an accepted method of investigation of patients with knee pain and possible meniscal tear. Multi-detector CT can potentially provide a more detailed and accurate examination due to its high-resolution crosssectional and multi-planar capabilities. The aim of this study was to assess the accuracy of our technique. All patients who underwent a multi-detector CT knee arthrogram in an initial 8 month period were identified. Initially the referring clinician was contacted. If the patient was referred to an orthopaedic surgeon the outcome of orthopaedic review was recorded using clinical, arthroscopic and / or MRI follow-up of the patient population. One hundred and twelve patients had a Multi-detector CT knee arthrogram performed within and 8 month period. Follow-up information was received in 69.7% of patients. Of these 68.9% had orthopaedic assessment - of which 69.2% underwent a knee arthroscopy.There was total agreement of findings in 67%, agreement of meniscal findings in 67% and chondral findings in 100%. Overall, orthopaedic opinion agreed with CT findings in 76.9%. At this stage, all meniscal tears not described in the initial CT arthrogram report have in retrospect been visible. Multi-detector CT knee arthrography is an accurate and elegant technique for investigation of knee pain, providing information in a format familiar to those reporting knee MRI. There is an initial learning curve. The technique is particularly useful in chondral assessment. It is accurate for meniscal pathology, although caution and recognition of potential pitfalls is required. Copyright (2002) Blackwell Science Pty Ltd

MR-guided MR arthrography of the shoulder

International Nuclear Information System (INIS)

Tratting, S.; Breitenseher, M.; Pretterklieber, M.; Kontaxis, G.; Rand, T.; Imhof, H.

1996-01-01

Purpose: To develop an MR-guided technique for joint puncture in MR arthrography of the shoulder and to confirm the intracapsular position of the needle tip by visualization of the flow of contrast media into the joint. Materials and methods: Three unfixed human shoulder joint specimens were examined on a 1.0 T unit. The optimal point of entrance and depth for joint puncture were estimated by means of MR-compatible markers on the skin. Needle orientation and localization of the needle tip (MR-compatible 22-gauge needle) in the shoulder joint were monitored by rapid localizer gradient-echo sequences in two orthogonal planes. To confirm the intracapsular position of the needle tip, diluted gadolinium-DTPA was administered via a long connecting tube and the flow of contrast media into the joint was viewed directly on an LCD screen using real-time MR imaging (local look technique). Results: The MR-compatible markers on the skin allowed determination of the optimal point of entrance and estimation of the depth for joint puncture. Passive visualization of the MR-compatible needle due to spin dephasing and signal loss provided adequate localization of the intra-articular needle tip position in all specimens, although significant artefacts were present on rapid localizer gradient-echo sequences with an increase in width of the apparent needle shaft. Real-time MR imaging of the flow of contrast media was possible using the local look technique and the LCD screen of the MR unit and allowed confirmation of the intracapsular position. Conclusion: MR-guided joint puncture and real-time MR-assisted contrast media application results in improved MR arthrography and may replace conventional fluoroscopic guidance. (orig.) [de

Accuracy of double-contrast arthrography and arthroscopy of the knee joint

International Nuclear Information System (INIS)

Thijn, C.J.P.

1982-01-01

Only in the diagnosis of medial meniscal lesions is double contrast arthrography superior to arthroscopy, provided that arthroscopy is carried out only from the anterolateral side (94% against 81% positive correlations). The rates in diagnosing lateral meniscal lesions are respectively 90% and 94.5%, in patellar chondropathy 55% and 99.5% respectively, and in diagnosting cruciate ligament lesions 69% and 97% respectively

Accuracy of double-contrast arthrography and arthroscopy of the knee joint

International Nuclear Information System (INIS)

Thijn, C.J.P.

1982-01-01

Only in the diagnosis of medial meniscal lesions is double contrast arthrography superior to arthroscopy, provided that arthroscopy is carried out only from the anterolateral side (94% against 81% positive correlations). The rates in diagnosing lateral meniscal lesions are respectively 90% and 94.5%, in patellar chondropathy 55% and 99.5% respectively, and in diagnosting cruciate ligament lesions 69% and 97% respectively. (orig.)

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

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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

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

International Nuclear Information System (INIS)

Chun, Kyung Ah; Kim, Min Sung; Kim, Young Joo

2010-01-01

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

Magnetodynamical resonance near the low-temperature phase transition in ErFeO3

International Nuclear Information System (INIS)

Dan'shin, N.K.; Kovtun, N.M.; Sdvizhkov, M.A.

1986-01-01

Magnetodynamical resonance (MDR) near low-temperature phase transition (PT) in erbium ortoferrite is investigated. At temperature below 4K (PT temperature) pt can be induced by a magnetic field. It is revealed that PT is accompained by partialsoftening of one of the magnetic resonance MR) branches. Besides MR soft mode resonance absorption was observed. This absorption is shown to be related to the excitation in a sample of dielectric resonance (DR). Essential differences of MDR near PT in ErFeO 3 are as follows: interaction between MR abd DR at PT takes place under softening of all interacting models; ErFeO 3 is characterized by a high value of permittivity epslon and by considerable anisotropy epsilon and magnetic permeability

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.

A comparison of arthrography to clinical diagnostics for diagnosing meniscal lesions

International Nuclear Information System (INIS)

Neuer, H.

1982-01-01

A comparative investigation as to the exactness of clinical and arthrographical diagnostics was carried out on 176 patients who were clinically examined and operated on in the period of 1972-1980. Using solely clinical diagnostics, the total rate of exactness was 90,9%, the exactness regarding the internal meniscal lesion being significantly higher (94.2%) than that regarding external meniscal lesion (76.7%). Using solely arthrographic diagnostics, the total rate of exactness was 82%, the rate for internal meniscus being significantly lower (83.9%) than that obtained using clinical diagnostics. As for the external meniscus, the exactness of arthrography differs only slightly from clinical diagnostics with 74.7%. The most frequent sources of error in arthorgraphy were found to be lesions of the posterior horn at the internal meniscus. In cases of external meniscal lesions, especially when an internal meniscal lesion was existing at the same time, both examination methods failed in 5 cases. For routine diagnosing of meniscal lesions, arthrography is not necessary. An accurate clinical examination and anamnesis bring very good and exact results and should therefore be given absolute priority. (orig./MG) [de

MDCT arthrography of the wrist: Diagnostic accuracy and indications

International Nuclear Information System (INIS)

De Filippo, Massimo; Pogliacomi, Francesco; Bertellini, Annalisa; Araoz, Philip A.; Averna, Raffaele; Sverzellati, Nicola; Ingegnoli, Anna; Corradi, Maurizio; Costantino, Cosimo; Zompatori, Maurizio

2010-01-01

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.

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.

Value of computed tomography arthrography with delayed acquisitions in the work-up of ganglion cysts of the tarsal tunnel: report of three cases

International Nuclear Information System (INIS)

Omoumi, Patrick; Gheldere, Antoine de; Leemrijse, Thibaut; Galant, Christine; Van den Bergh, Peter; Malghem, Jacques; Simoni, Paolo; Berg, Bruno C.V.; Lecouvet, Frederic E.

2010-01-01

Ganglion cysts are a common cause of tarsal tunnel syndrome. As in other locations, these cysts are believed to communicate with neighboring joints. The positive diagnosis and preoperative work-up of these cysts require identification and location of the cyst pedicles so that they may be excised and the risk of recurrence decreased. This can be challenging with ultrasonography and magnetic resonance (MR) imaging. We present three cases of symptomatic ganglion cysts of the tarsal tunnel, diagnosed by MR imaging, where computed tomography (CT) arthrography with delayed acquisitions helped to confirm the diagnosis and identify precisely the topography of the communication with the subtalar joint. These cases provide new evidence of the articular origin of ganglion cysts developing in the tarsal tunnel. (orig.)

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.)

Cost-effectiveness of positive contrast and nuclear arthrography in patients who underwent total hip arthroplasty

International Nuclear Information System (INIS)

Swan, J.S.; Braunstein, E.M.; Capello, W.; Wellman, H.

1989-01-01

The authors have compared the cost effectiveness of contrast arthrography (CA) and nuclear arthrography (NA), in which In-111 chloride is injected with the contrast material, of total hip arthroplasties. Their series included 48 cases of surgically proved loose femoral components. The cost per true-positive result was obtained by taking the total cost of the examinations in surgically proved cases and dividing by the number of true-position cases. The cost of CA was $297 and the cost of NA was $335. For CA, the cost per true positive was $1,018, and for the NA the cost per true positive was $946. In spite of higher initial cost, NA is more cost effective than CA on a cost per true-positive case basis. NA is cost effective in evaluating hip arthroplasties in which there is suspicion of a loose femoral component

Acoustic spin pumping in magnetoelectric bulk acoustic wave resonator

Directory of Open Access Journals (Sweden)

N. I. Polzikova

2016-05-01

Full Text Available We present the generation and detection of spin currents by using magnetoelastic resonance excitation in a magnetoelectric composite high overtone bulk acoustic wave (BAW resonator (HBAR formed by a Al-ZnO-Al-GGG-YIG-Pt structure. Transversal BAW drives magnetization oscillations in YIG film at a given resonant magnetic field, and the resonant magneto-elastic coupling establishes the spin-current generation at the Pt/YIG interface. Due to the inverse spin Hall effect (ISHE this BAW-driven spin current is converted to a dc voltage in the Pt layer. The dependence of the measured voltage both on magnetic field and frequency has a resonant character. The voltage is determined by the acoustic power in HBAR and changes its sign upon magnetic field reversal. We compare the experimentally observed amplitudes of the ISHE electrical field achieved by our method and other approaches to spin current generation that use surface acoustic waves and microwave resonators for ferromagnetic resonance excitation, with the theoretically expected values.

Acoustic spin pumping in magnetoelectric bulk acoustic wave resonator

Energy Technology Data Exchange (ETDEWEB)

Polzikova, N. I., E-mail: polz@cplire.ru; Alekseev, S. G.; Pyataikin, I. I.; Kotelyanskii, I. M.; Luzanov, V. A.; Orlov, A. P. [Kotel’nikov Institute of Radio Engineering and Electronics of Russian Academy of Sciences, Mokhovaya 11, building 7, Moscow, 125009 (Russian Federation)

2016-05-15

We present the generation and detection of spin currents by using magnetoelastic resonance excitation in a magnetoelectric composite high overtone bulk acoustic wave (BAW) resonator (HBAR) formed by a Al-ZnO-Al-GGG-YIG-Pt structure. Transversal BAW drives magnetization oscillations in YIG film at a given resonant magnetic field, and the resonant magneto-elastic coupling establishes the spin-current generation at the Pt/YIG interface. Due to the inverse spin Hall effect (ISHE) this BAW-driven spin current is converted to a dc voltage in the Pt layer. The dependence of the measured voltage both on magnetic field and frequency has a resonant character. The voltage is determined by the acoustic power in HBAR and changes its sign upon magnetic field reversal. We compare the experimentally observed amplitudes of the ISHE electrical field achieved by our method and other approaches to spin current generation that use surface acoustic waves and microwave resonators for ferromagnetic resonance excitation, with the theoretically expected values.

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

International Nuclear Information System (INIS)

Choi, Jung Ah; Suh, Sang Il; Kim, Baek Hyun; Cha, Sang Hoon; Kim, Myung Gyu; Lee, Ki Yeol; Lee, Chang Hee

2001-01-01

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 features are seen at

Partial radiative capture of resonance neutrons; Capture radiative partielle des neutrons de resonance

Energy Technology Data Exchange (ETDEWEB)

Samour, C [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

1969-07-01

The radiative capture of resonance neutrons has been studied near the Saclay linac between 0.5 and 700 eV with time-of-flight method and a Ge(Li) detector. {sup 195}Pt + n and {sup 183}W + n allow the study of the distribution of partial radiative widths and their eventual correlation and also the variation of < {gamma}{sub {gamma}{sub i}} > with E{sub {gamma}}. The mean values of Ml and El transition intensities are compared in several tin isotopes. Interference effects, either between resonances or between direct capture and resonant capture are found in {sup 195}Pt + n, {sup 197}Au + n and {sup 59}Co + n. The excited level schemes of a great deal of nuclei are obtained and compared with theoretical predictions. This study has been completed by an analysis of thermal spectrum. (author) [French] La capture radiative des neutrons de resonance a ete etudiee pres de l'accelerateur lineaire de Saclay entre 0,5 et 700 eV a l'aide de la methode du temps-de-vol et d'un detecteur Ge(Li). Les noyaux {sup 195}Pt + n et {sup 183}W + n permettent l'analyse de la distribution de resonance en resonance des largeurs radiatives partielles {gamma}{sub {gamma}{sub i}} et de leur eventuelle correlation, ainsi que l'etude de la variation de < {gamma}{sub {gamma}{sub i}} > en fonction de E{sub {gamma}}. Les intensites moyennes des transitions Ml et El sont comparees pour quelques isotopes de l'etain. Des effets d'interference, soit entre resonances, soit entre capture directe et capture resonnante sont mis en evidence dans {sup 195}Pt + n, {sup 197}Au + n et {sup 59}Co + n. Enfin les schemas des etats excites d'un grand nombre de noyaux sont obtenus et compares avec les predictions theoriques. Cette etude a ete completee par une analyse des spectres thermiques. (auteur)

Partial radiative capture of resonance neutrons; Capture radiative partielle des neutrons de resonance

Energy Technology Data Exchange (ETDEWEB)

Samour, C. [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

1969-07-01

The radiative capture of resonance neutrons has been studied near the Saclay linac between 0.5 and 700 eV with time-of-flight method and a Ge(Li) detector. {sup 195}Pt + n and {sup 183}W + n allow the study of the distribution of partial radiative widths and their eventual correlation and also the variation of < {gamma}{sub {gamma}{sub i}} > with E{sub {gamma}}. The mean values of Ml and El transition intensities are compared in several tin isotopes. Interference effects, either between resonances or between direct capture and resonant capture are found in {sup 195}Pt + n, {sup 197}Au + n and {sup 59}Co + n. The excited level schemes of a great deal of nuclei are obtained and compared with theoretical predictions. This study has been completed by an analysis of thermal spectrum. (author) [French] La capture radiative des neutrons de resonance a ete etudiee pres de l'accelerateur lineaire de Saclay entre 0,5 et 700 eV a l'aide de la methode du temps-de-vol et d'un detecteur Ge(Li). Les noyaux {sup 195}Pt + n et {sup 183}W + n permettent l'analyse de la distribution de resonance en resonance des largeurs radiatives partielles {gamma}{sub {gamma}{sub i}} et de leur eventuelle correlation, ainsi que l'etude de la variation de < {gamma}{sub {gamma}{sub i}} > en fonction de E{sub {gamma}}. Les intensites moyennes des transitions Ml et El sont comparees pour quelques isotopes de l'etain. Des effets d'interference, soit entre resonances, soit entre capture directe et capture resonnante sont mis en evidence dans {sup 195}Pt + n, {sup 197}Au + n et {sup 59}Co + n. Enfin les schemas des etats excites d'un grand nombre de noyaux sont obtenus et compares avec les predictions theoriques. Cette etude a ete completee par une analyse des spectres thermiques. (auteur)

Mechanical properties of non-centrosymmetric CePt3Si and CePt3B

Science.gov (United States)

Rogl, G.; Legut, D.; Sýkora, R.; Müller, P.; Müller, H.; Bauer, E.; Puchegger, S.; Zehetbauer, M.; Rogl, P.

2017-05-01

Elastic moduli, hardness (both at room temperature) and thermal expansion (4.2-670 K) have been experimentally determined for polycrystalline CePt3Si and its prototype compound CePt3B as well as for single-crystalline CePt3Si. Resonant ultrasound spectroscopy was used to determine elastic properties (Young’s modulus E and Poisson’s ratio ν) via the eigenfrequencies of the sample and the knowledge of sample mass and dimensions. Bulk and shear moduli were calculated from E and ν, and the respective Debye temperatures were derived. In addition, ab initio DFT calculations were carried out for both compounds. A comparison of parameters evaluated from DFT with those of experiments revealed, in general, satisfactory agreement. Positive and negative thermal expansion values obtained from CePt3Si single crystal data are fairly well explained in terms of the crystalline electric field model, using CEF parameters derived recently from inelastic neutron scattering. DFT calculations, in addition, demonstrate that the atomic vibrations keep almost unaffected by the antisymmetric spin-orbit coupling present in systems with crystal structures having no inversion symmetry. This is opposite to electronic properties, where the antisymmetric spin-orbit interaction has shown to distinctly influence features like the superconducting condensate of CePt3Si.

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.

[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.

Arthrography

Medline Plus

Full Text Available ... bear denotes child-specific content. Related Articles and Media Magnetic Resonance Imaging (MRI) - Musculoskeletal Radiation Dose in X-Ray and CT Exams Contrast Materials Magnetic Resonance Imaging (MRI) - Shoulder X-ray, ...

Importance of transthoracic X-ray in arthrography of the shoulder

International Nuclear Information System (INIS)

Beck, A.; Papacharalampous, X.; Grosser, G.; Noeldge, G.

1988-01-01

Even in this era of sonography, arthrography of the shoulder is an important diagnostic investigation, making it possible to exclude unrecognized connective tissue lesions in patients with chronic shoulder pain resisant to therapy. Sometimes standard X-ray techniques do not yield all the information the surgeon needs about ventral or dorsal localization of a rotator-cuff rupture. An Additional approach to the joint is needed: A transthoracic lateral-view X-ray provides the surgeon with adequate information to help in selection of the most appropriate operative approach to the shoulder. (orig.) [de

Value of arthrography in the evaluation of sacroiliac pain

International Nuclear Information System (INIS)

Bobechko, P.

1987-01-01

The authors attempted to assess the sacroiliac joint as a source of low back pain by using arthrography with a local anesthetic injection. Intraarticular injection of contrast agent and local anesthetic was attempted in 29 patients (35 joints), aged 24-69 years. The intraarticular injection was successful in 24 cases (68.5%). Periarticular infiltration of anesthetic was done in the remaining 11 cases. Pain relief was obtained in 19 cases, of which 13 involved intraarticular and six involved periarticular injections. On the basis of these results, patients were treated by surgical fusion, medication, or conservative management. Referring physicians found that the results obtained were valuable and helpful in assessing these patients

Laser magnetic resonance spectroscopy

International Nuclear Information System (INIS)

Ferrari, C.A.

1985-01-01

The technique of laser resonance magnetic resonance allows one to study the high-resolution spectroscopy of transient paramagnetic species, viz, atoms, radicals, and molecular ions. This article is a brief exposition of the method, describing the principles, instrumentation and applicability of the IR and FIR-LMR and shows results of HF + . (Author) [pt

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.

Particle in a box in PT-symmetric quantum mechanics and an electromagnetic analog

Science.gov (United States)

Dasarathy, Anirudh; Isaacson, Joshua P.; Jones-Smith, Katherine; Tabachnik, Jason; Mathur, Harsh

2013-06-01

In PT-symmetric quantum mechanics a fundamental principle of quantum mechanics, that the Hamiltonian must be Hermitian, is replaced by another set of requirements, including notably symmetry under PT, where P denotes parity and T denotes time reversal. Here we study the role of boundary conditions in PT-symmetric quantum mechanics by constructing a simple model that is the PT-symmetric analog of a particle in a box. The model has the usual particle-in-a-box Hamiltonian but boundary conditions that respect PT symmetry rather than Hermiticity. We find that for a broad class of PT-symmetric boundary conditions the model respects the condition of unbroken PT symmetry, namely, that the Hamiltonian and the symmetry operator PT have simultaneous eigenfunctions, implying that the energy eigenvalues are real. We also find that the Hamiltonian is self-adjoint under the PT-symmetric inner product. Thus we obtain a simple soluble model that fulfills all the requirements of PT-symmetric quantum mechanics. In the second part of this paper we formulate a variational principle for PT-symmetric quantum mechanics that is the analog of the textbook Rayleigh-Ritz principle. Finally we consider electromagnetic analogs of the PT-symmetric particle in a box. We show that the isolated particle in a box may be realized as a Fabry-Perot cavity between an absorbing medium and its conjugate gain medium. Coupling the cavity to an external continuum of incoming and outgoing states turns the energy levels of the box into sharp resonances. Remarkably we find that the resonances have a Breit-Wigner line shape in transmission and a Fano line shape in reflection; by contrast, in the corresponding Hermitian case the line shapes always have a Breit-Wigner form in both transmission and reflection.

Magnetic resonance imaging of the triangular fibrocartilage complex. Usefulness of the fat suppression MRI

Energy Technology Data Exchange (ETDEWEB)

Nakamura, Toshiyasu [Fujita Health Univ., Nagoya (Japan). Second Hospital; Yabe, Yutaka; Horiuchi, Yukio; Kikuchi, Yoshito; Makita, Satoo

1996-08-01

Advances in magnetic resonance imaging (MRI) now allow for the visualization of small structures, such as the triangular fibrocartilage complex (TFCC) of the wrist. Recent investigators suggested that MRI is useful in delineation of the TFCC itself and its abnormality, and supported that diagnostic value of MRI for the TFCC tears is almost equal to those of arthrography and arthroscopy. In contrast, there were several reports that representation of the TFCC in MRI was less worth than in arthrography. Further, it was reported that MRI was not useful because abnormal findings existed at normal volunteers` wrists. Recent development of the pulse sequence is remarkable, such as gradient echo, fast spin echo and fat suppression method. However, as the previous MR studies of the TFCC mainly using conventional spin echo pulse sequence, there were a few comparison of each pulse sequence and we do not know how each pulse sequence delineates the TFCC. Therefore, we studied MRI of the TFCC using several pulse sequence in normal volunteers, and compared MR slices of the TFCC with corresponding histological sections to evaluate shape detectability of MRI. (J.P.N.)

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.)

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.)

Epinephrine inhanced double contrast knee arthrography

International Nuclear Information System (INIS)

Lee, Jae Mun; Choi, Byung Ihn

1981-01-01

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 (ρ value < 0.01 at 2 minutes, ρ < 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 (ρ < 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(+) group

Interactions among resonances in the unresolved region

International Nuclear Information System (INIS)

Queiroz Bogado Leite, S. de.

1982-11-01

The theory on resonance absorption in the unresolved region is reviewed and a subroutine is presented, optional to UNRES in MC 2 code. Comparisons with the isolated resonance model suggest the necessity, in some cases, of considering interference and overlapping effects among resonances of the system. (Author) [pt

The discovery of resonances in multibaryon systems. Pt. 3. Λ p-resonances

International Nuclear Information System (INIS)

Shahbazian, B.A.; Temnikov, P.P.; Timonina, A.A.; Rozhdestvenskij, A.M.

1978-01-01

Dibaryon Λ p resonance of 2256 MeV/c 2 mass, GITA 2 (depending on the spin Jsub(Λp)) width, and Jsup(p) > O + spin-parity assignments is discovered. The statistical significance of the corresponding peak in Λ p effective mass spectra is defined by more than five standard deviations. Its production effective cross section in n 12 C collisions at =7.0 GeV/c is estimated to be sigmasub(pr) (2256)=(85.3+-20.0)μb, whereas the formation effective cross section in Λ p → Λ p interactions is sigmasub(f) (2256) = 5.3(2Jsub(Λp)+1) mb. The Λp effective mass spectra which have been investigated in this experiment reveal, apart the well known approximately(Msub(Λ+Msub(p)) MeV/c 2 and 2128 MeV/c 2 peaks, enhancements including 2256 MeV/c 2 peak near the most of the resonance mass values predicted by MIT Bag Model. Possible mechanisms of multibaryon resonance formation are discussed. According to the hypercharge selection rule Y <= 1 multibaryon resonances are shown to be ultra-high density superstrange objects

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.

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

Energy Technology Data Exchange (ETDEWEB)

Lee, H. K., E-mail: hankl@uci.edu; Barsukov, I.; Yang, L.; Krivorotov, I. N. [Physics and Astronomy, University of California, Irvine, California 92697 (United States); Swartz, A. G.; Kim, B. [Geballe Laboratory for Advanced Materials, Department of Applied Physics, Stanford University, Stanford, California 94305 (United States); Hwang, H. Y. [Geballe Laboratory for Advanced Materials, Department of Applied Physics, Stanford University, Stanford, California 94305 (United States); Stanford Institute for Materials and Energy Sciences, SLAC National Accelerator Laboratory, Menlo Park, California 94025 (United States)

2016-05-15

We report ferromagnetic resonance measurements of magnetic anisotropy and damping in epitaxial La{sub 0.7}Sr{sub 0.3}MnO{sub 3} (LSMO) and Pt capped LSMO thin films on SrTiO{sub 3} (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{sup −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.

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.)

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

International Nuclear Information System (INIS)

Holzapfel, Konstantin; Waldt, Simone; Bruegel, Melanie; Rummeny, Ernst J.; Woertler, Klaus; Paul, Jochen; Imhoff, Andreas B.; Heinrich, Petra

2010-01-01

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 κ 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 (κ = 0.82) for detection and substantial (κ = 0.63) for classification of SLAP lesions. For each reader intraobserver agreement was excellent for detection (κ = 0.93, κ = 0.97, κ = 0.97) and classification (κ = 0.94, κ = 0.84, κ = 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.)

MR-imaging of anterior tibiotalar impingement syndrome: Agreement, sensitivity and specificity of MR-imaging and indirect MR-arthrography

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Haller, Joerg [Department of Radiology, Hanusch Hospital, Heinrich Collin-Strasse 30, A-1140 Vienna (Austria); Ludwig Boltzmann Institute for Osteology, Hanusch Hospital, Heinrich Collin-Strasse 30, A-1140 Vienna (Austria); Bernt, Reinhard [Department of Radiology, Hanusch Hospital, Heinrich Collin-Strasse 30, A-1140 Vienna (Austria)]. E-mail: reinhard.bernt@wgkk.sozvers.at; Seeger, Thomas [Department of Trauma Surgery, Hanusch Hospital, Heinrich Collin-Strasse 30, A-1140 Vienna (Austria); Weissenbaeck, Alexander [Department of Trauma Surgery, Hanusch Hospital, Heinrich Collin-Strasse 30, A-1140 Vienna (Austria); Tuechler, Heinrich [Ludwig Boltzmann Institute for Hematology, Hanusch Hospital, Heinrich Collin-Strasse 30, A-1140 Vienna (Austria); Resnick, Donald [Department of Radiology, VA Medical Center, UCSD, 3350 La Jolla Village Dr, San Diego, CA 92161 (United States)

2006-06-15

Objective: To clarify the role of MR-imaging in the diagnosis of anterior ankle impingement syndromes. Materials and methods: We prospectively examined 51 consecutive patients with chronic ankle pain by MR-imaging. Arthroscopy was performed in 29 patients who previously underwent non-enhanced MR-imaging; in 11 patients, indirect MR-arthrography additionally was performed. MR-examinations were correlated with clinical findings; MR and arthroscopy scores were statistically compared, agreement was measured. Results: Arthroscopy demonstrated granulation tissue in the lateral gutter (38%) and anterior recess (31%), lesions of the anterior tibiofibular (31%) and the anterior talofibular ligament (21%) as well as intraarticular bodies (10%). Stenosing tenosynovitis and a ganglionic cyst were revealed as extraarticular causes for chronic ankle pain by MR-examination (17%). Agreement of MR-imaging and arthroscopy was fair for the anterior talofibular ligament and the anterior joint cavity (kappa 0.40). Major discrepancy was found for non-enhanced MR scans (kappa 0.49) when compared with indirect MR-arthrography (kappa 0.03) in the anterior cavity. The sensitivity for lesions of the anterior talofibular and calcaneofibular ligament and the anterior cavity (0.91-0.87) detected by MR-imaging was superior in comparison to lesions of the anterior tibiofibular ligament and anteromedial cavity (0.50-0.24). Conclusion: MR-imaging provides additional information about the mechanics of chronic ankle impingement rather than an accurate diagnosis of this clinical entity. The method is helpful in differentiating extra- from intra-articular causes of ankle impingement. Indirect MR-arthrography has little or no additional value in patients with ankle impingement syndrome.

MR-imaging of anterior tibiotalar impingement syndrome: Agreement, sensitivity and specificity of MR-imaging and indirect MR-arthrography

International Nuclear Information System (INIS)

Haller, Joerg; Bernt, Reinhard; Seeger, Thomas; Weissenbaeck, Alexander; Tuechler, Heinrich; Resnick, Donald

2006-01-01

Objective: To clarify the role of MR-imaging in the diagnosis of anterior ankle impingement syndromes. Materials and methods: We prospectively examined 51 consecutive patients with chronic ankle pain by MR-imaging. Arthroscopy was performed in 29 patients who previously underwent non-enhanced MR-imaging; in 11 patients, indirect MR-arthrography additionally was performed. MR-examinations were correlated with clinical findings; MR and arthroscopy scores were statistically compared, agreement was measured. Results: Arthroscopy demonstrated granulation tissue in the lateral gutter (38%) and anterior recess (31%), lesions of the anterior tibiofibular (31%) and the anterior talofibular ligament (21%) as well as intraarticular bodies (10%). Stenosing tenosynovitis and a ganglionic cyst were revealed as extraarticular causes for chronic ankle pain by MR-examination (17%). Agreement of MR-imaging and arthroscopy was fair for the anterior talofibular ligament and the anterior joint cavity (kappa 0.40). Major discrepancy was found for non-enhanced MR scans (kappa 0.49) when compared with indirect MR-arthrography (kappa 0.03) in the anterior cavity. The sensitivity for lesions of the anterior talofibular and calcaneofibular ligament and the anterior cavity (0.91-0.87) detected by MR-imaging was superior in comparison to lesions of the anterior tibiofibular ligament and anteromedial cavity (0.50-0.24). Conclusion: MR-imaging provides additional information about the mechanics of chronic ankle impingement rather than an accurate diagnosis of this clinical entity. The method is helpful in differentiating extra- from intra-articular causes of ankle impingement. Indirect MR-arthrography has little or no additional value in patients with ankle impingement syndrome

The failed postoperative shoulder: Role of double contrast CT arthrography

International Nuclear Information System (INIS)

Singson, R.D.; Feldman, F.; Bigliani, L.

1986-01-01

Various types of reparative and corrective operations on the shoulder joint are being increasingly undertaken. Defining residual, new, or acutely acquired pathology in the postoperative period is exceedingly difficult because of extensive surgical alterations. Since patients may be symptomatic or recurrently symptomatic postoperatively, judgments must be made regarding the failure of the initial repair, or new superimposed insults. CT double-contrast arthrography, performed in a series of symptomatic patients after shoulder arthroplasty for instability, successfully demonstrated responsible residual or recurrent pathologic processes, including persistent Bankart lesions, glenoid rim fractures, improper hardware placement, and migration of metallic hardware. These and other examples of pathology are illustrated and discussed

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

International Nuclear Information System (INIS)

Carroll, K.W.; Helms, C.A.

2002-01-01

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.)

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

International Nuclear Information System (INIS)

Lee, Guen Young; Kim, Baek Hyun; Park, Jong Woong

2011-01-01

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

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

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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

Partial radiative capture of resonance neutrons

International Nuclear Information System (INIS)

Samour, C.

1969-01-01

The radiative capture of resonance neutrons has been studied near the Saclay linac between 0.5 and 700 eV with time-of-flight method and a Ge(Li) detector. 195 Pt + n and 183 W + n allow the study of the distribution of partial radiative widths and their eventual correlation and also the variation of γ i > with E γ . The mean values of Ml and El transition intensities are compared in several tin isotopes. Interference effects, either between resonances or between direct capture and resonant capture are found in 195 Pt + n, 197 Au + n and 59 Co + n. The excited level schemes of a great deal of nuclei are obtained and compared with theoretical predictions. This study has been completed by an analysis of thermal spectrum. (author) [fr

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.

Clinical and radiological analysis on the double contrast arthrography of the knee

International Nuclear Information System (INIS)

Sol, Chang Hyo; Lee, Suck Hong; Moon, Tae Yong; Kim, Byung Soo

1980-01-01

The author has performed double contrast arthrography of knee in 96 cases at Busan National University Hospital for about 4 years from May 1976 to April 1980. The 31 cases of them were analyzed both clinically and radiographycally with the background of definite diagnosis confirmed by operation. The results are as follows. 1. Of the 31 cases, 25 cases were male (80.6%), and 6 cases were female (19.4%). Male exceeded female in ratio of 5 : 1. 2. 22 cases (70.1%) were distributed from 15 to 26 years of age. 3. The left knee joint was a more prevalent site. The ratio of left to right was 16 : 14. One case was bilateral. 4. In 17 cases (45.2%) of the 31 cases, there was a positive history of trauma. 14 cases had no specific history (54.8%). 5. The operative findings showed lateral meniscus lesion in 25 cases (80.6%): medical meniscus lesion in 2 cases (6.5%); discoid meniscus in 2 cases (6.5%); lateral menisectomy in 1 cases (3.2%); and lateral meniscus lesion with medial collateral ligament tearing in 1 case (3.2%). 6. In 25 cases of the 31 cases, the radiologic abnormal findings corresponded to the operative findings. 5 cases revealed somewhat different features with the operative findings. One case which showed no abnormal roentgenographic findings was found to have abnormality at operation. As a result, the diagnostic accuracy of arthrography was 96.8%

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

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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.)

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

International Nuclear Information System (INIS)

Zubler, Christoph; Mengiardi, Bernard; Schmid, Marius R.; Hodler, Juerg; Pfirrmann, Christian W.A.; Jost, Bernhard

2007-01-01

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.)

Direct MR-arthrography of the shoulder with maximum capsular distension for surgical planning

International Nuclear Information System (INIS)

Drescher, R.; Rothenburg, T. von; Koester, O.; Schmid, G.; Ludwig, J.

2004-01-01

Purpose: To evaluate the effectiveness of direct MR arthrography of the glenohumeral joint with maximum distension of the joint capsule in patients with glenohumeral instability for preoperative diagnosis and for determining the method of surgical intervention. Materials and Methods: MR arthrography of the shoulder joint was performed on a 1.5 T system in 38 patients. All patients suffered from anterior or bidirectional instability. Using a fluoroscopically guided posterior approach, a 1% dilution of dimeglumine gadopentetate (5 mmol Gd-DTPA/l) was injected until full capsular stretching was achieved. MR imaging protocol included fat-saturated transversal, oblique-coronal and oblique-sagittal T1-weighted spin-echo, T1-weighted 3-D and transversal T2-weighted Flash-2D. Results: MR imaging revealed significant capsule distention in 22 patients and ventral capsule defects in 9 patients. Labral lesions were depicted in 25 patients, bicipital tendon lesions in 4 patients and partial ruptures of the rotator cuff in 3 patients. 15 of the 38 patients underwent surgery. Areas of pathologic laxity of the glenohumeral capsule were correctly described in all cases. In 12 of 15 patients, the best method of intervention could be determined prospectively. In 3 of 15 patients, the necessary operation was overestimated. Regarding labral ruptures, MRI had a sensitivity of 88%, a specificity of 86%, and a diagnostic accuracy of 87%. (orig.)

Gradient-recalled echo sequences in direct shoulder MR arthrography for evaluating the labrum

International Nuclear Information System (INIS)

Lee, Marc J.; Motamedi, Kambiz; Chow, Kira; Seeger, Leanne L.

2008-01-01

The purpose of this study was to determine the utility of fat-suppressed gradient-recalled echo (GRE) compared with conventional spin echo T1-weighted (T1W) sequences in direct shoulder MR arthrography for evaluating labral tears. Three musculoskeletal radiologists retrospectively reviewed MR arthrograms performed over a 12-month period for which surgical correlation was available. Of 180 serial arthrograms, 31 patients had surgery with a mean of 48 days following imaging. Paired coronal oblique and axial T1W or GRE sequences were analyzed by consensus for labral tear (coronal oblique two-dimensional multi-echo data image combination, 2D MEDIC; and axial three-dimensional double-echo steady-state, 3D DESS; Siemens MAGNETOM Sonata 1.5-T MR system). Interpretations were correlated with operative reports. Of 31 shoulders, 25 had labral tears at surgery. The GRE sequences depicted labral tears in 22, while T1W images depicted tears in 16 (sensitivity 88% versus 64%; p 0.7). Specificities were somewhat lower for GRE. Thin section GRE sequences are more sensitive than T1W for the detection of anterior and posterior labral tears. As the specificity of GRE was lower, it should be considered as an adjunctive imaging sequence that may improve depiction of labral tears, particularly smaller tears, in routine MR arthrography protocols. (orig.)

Four years of experience with temporamandibular joint (TMJ) arthrography

International Nuclear Information System (INIS)

Duarte Filho, D.L.; Wagner, R.

1990-01-01

The imaging investigation of the internal derangements of temporomandibular joint (TMJ) has been recently enriched with state of the art tools, such as CT and MRI. However these equipments are not widely available in our country. In addition, some lesions such as perforation of the MJ meniscus, are not demonstrated by either one of these methods, been fairly easily showed by arthorography. The purpose of this paper is to show our experience with 386 arthrograms performed in 193 patients. Our results are compatible with those of the literature. In the last group of 176 patients, we have abandonned the local anesthesia procedure, with good advantages. Arthrography is a very usefull method in the evaluation of TMJ and should be more used in our country. (author)

Multimachine subsynchronous resonance: Pt. 2

International Nuclear Information System (INIS)

Lahoud, M.A.; Harley, R.G.; Levy, D.C.

1984-01-01

This paper describes a theoretical investigation into the subsynchronous resonance (SSR) behaviour of a power system containing synchronous generators, induction motors and series capacitors. By applying eigenvalue techniques, attention is paid to the effect of replacing the induction motor by an equivalent fixed resistor-inductor (R-L) load. Nonlinear transient simulations and their Fast Fourier Transforms (FFT's) are also used to investigate the effects of the complexity of the mechanical model of the generator on the SSR predictions. The results show that the model used for the induction motor has a significant effect on the SSR behaviour of a multimachine system

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.

An analytical approximation for resonance integral

International Nuclear Information System (INIS)

Magalhaes, C.G. de; Martinez, A.S.

1985-01-01

It is developed a method which allows to obtain an analytical solution for the resonance integral. The problem formulation is completely theoretical and based in concepts of physics of general character. The analytical expression for integral does not involve any empiric correlation or parameter. Results of approximation are compared with pattern values for each individual resonance and for sum of all resonances. (M.C.K.) [pt

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

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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.)

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.)

[Contribution of echogradient magnetic resonance imaging in the study of subacromial diseases. Surgical and arthrographic correlations].

Science.gov (United States)

Touzard, R C; Pigeau, I; Doursounian, L; Maigne, J Y; Vadrot, D

1991-01-01

Fifteen asymptomatic volunteers and 300 patients with suspected lesions of the rotator cuff were examined with T2*- and proton density-weighted gradient echo (T2*-Rho-GEI) MRI sequences (500-700 ms/30 ms/30 degrees) with a 0.5 T (GE-CGR) system and an adapted surface coil. For the patients, the findings were compared with those of arthrography in 130 cases and of surgery in 42 cases. For the operated patients, T2*-Rho-GEI and arthrography allowed correctly diagnosing 31 complete ruptures (CR). However, surgical exploration of the ruptures showed that T2*-Rho-GEI showed the actual extent of the rupture and the degree of tendon retraction better than arthrography. T2*-Rho-GEI also provides information about the thickness and trophicity of the remaining cuff and on local muscle trophicity. T2*-Rho-GEI allows directly evaluating the tendon of the long head of the biceps both in its extra-articular and its intra-articular parts. In 3 cases of complete cuff rupture, MRI allowed detecting 3 associated lesions of the anterior labrum, which had not been suspected on the clinical examination and had not been demonstrated by conventional arthrography. Lastly, out of 12 cases of deep incomplete rupture (n = 12) correctly diagnosed with MRI, 5 had been undetected on arthrography. Similarly, 8 cases of inflammatory alterations suspected with T2*-Rho-GEI and confirmed by surgery had not been recognized with arthrography. For the non-operated patients, T2*-Rho-GEI and arthrography had corresponding results for the diagnosis of CR (8 cases), of DIR (6 cases) and of intact cuff (6 cases).(ABSTRACT TRUNCATED AT 250 WORDS)

Paralabral cysts in the hip joint: findings at MR arthrography

International Nuclear Information System (INIS)

Magerkurth, Olaf; Jacobson, Jon A.; Girish, Gandikota; Kalume Brigido, Monica; Fessell, David; Bedi, Asheesh

2012-01-01

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.)

Diagnosis of superior labral lesions: comparison of noncontrast MRI with indirect MR arthrography in unexercised shoulders

International Nuclear Information System (INIS)

Dinauer, Philip A.; Flemming, Donald J.; Murphy, Kevin P.; Doukas, William C.

2007-01-01

To prospectively compare the accuracy of noncontrast magnetic resonance imaging (MRI) with indirect MR arthrography (I-MRa) of unexercised shoulders for diagnosis of superior glenoid labral lesions. Institutional Review Board approval and patient informed consent were obtained for this prospective study. Superior labral findings on shoulder MRI and unexercised I-MRa studies of 104 patients were correlated with findings at arthroscopic shoulder surgery. Two musculoskeletal radiologists independently reviewed the two sets of MR images while blinded to arthroscopic results. For each radiologist, the McNemar test was used to detect statistically significant differences between techniques. The superior labrum was intact in 24 and abnormal in 80 subjects. For detection of superior labral lesions by each radiologist, I-MRa was more sensitive (84-91%) than MRI (66-85%), with statistically significant improvement in sensitivity for one reader (p = 0.003). However, I-MRa was less specific (58-71%) than MRI (75-83%). Overall, accuracy was slightly improved on I-MRa (78-86%) compared with MRI (70-83%), but this difference was not statistically significant for either reader. Compared with noncontrast MRI, I-MRa was more sensitive for diagnosis of superior glenoid labral lesions. However, the diagnostic value of I-MRa in shoulders remaining at rest is potentially limited by decreased specificity of the technique. (orig.)

Slowing down with resonance absorption

International Nuclear Information System (INIS)

Moura Neto, C. de; Nair, R.P.K.

1979-08-01

The presence of heavy nuclei in nuclear reactors, in significant concentrations, facilitates the appearance of absorption resonances. For the moderation in the presence of absorbers an exact solution of the integral equations is possible by numerical methods. Approximated solutions for separated resonances in function of the practical width, (NR and NRIM approximations) are discussed in this paper. The method is generalized, presenting the solution by an intermediate approximation, in the definition of the resonance integral. (Author) [pt

Coxarthrosis - a radiological approach and guidelines

International Nuclear Information System (INIS)

Schueller, G.; Schueller-Weidekamm, C.

2012-01-01

Coxarthrosis is one of the most frequent indications in radiological practice with a prevalence as high as 8%. Radiography, sonography, computed tomography, magnetic resonance imaging. Magnetic resonance arthrography for detection of early stages of labral and chondral pathologies as well as detection of osteonecrosis at an early stage. Czerny C, Hofmann S, Neuhold A et al. (1996) Lesions of the acetabular labrum: accuracy of MR imaging and MR arthrography in detection and staging. Radiology 200(1):225-230. Czerny C, Oschatz E, Neuhold A et al. (2002) [MR arthrography of the hip joint]. Radiologe 42(6):451-456. Kramer J, Breitenseher M, Imhof H et al. (2000) [Diagnostic imaging in femur head necrosis]. Orthopade 29(5):380-388. Is already established in clinical practice. Each modality has relevant indications. (orig.) [de

Usefulness of sono-guided needle puncture for MR arthrography of the shoulder

International Nuclear Information System (INIS)

Choi, Jae Woong; Hong, Suk Ju; Suh, San Il; Yong, Hwan Suk; Kim, Jung Hyuk; Park, Cheol Min; Suh, Won Hyuck; Kim, Myung Gyu

2000-01-01

To evaluate the usefulness of sono-guided needle puncture for MR arthrography of the shoulder to locate the path of access and to control the correct placement of the needle into the shoulder. Fifteen patients with suspicion of shoulder pathology were included in this study. Patients were laid in supine positions with the arm extended and slightly abducted, the palm of the hand facing upward. A sonographic unit with a high resolution transducer with 7.5 MHz linear array was used. Axial images in the anterior aspect of the shoulder were obtained to localize the coracoid process and the anteromedical portion of the humerus. Using an aseptic technique, a 21-guage needle was advanced into the shoulder joint under ultrasonographic guidance. When the needle made contract with the articular cartilage of the humeral head, the needle was tiled to position is point in the articular cavity. Solution of 0.1 ml gadopentetate dimeglumine in 25 ml of normal saline was prepared and 12-16 ml was injected into the joint cavity. The intra-articular position of the needle and the compete distension of the shoulder joint were again confirmed by sonography. The needle was accurately placed in 14 out of 15 patients without damage to neighboring structures. It took 10 to 15 minutes to complete the procedure in 14 patients. No side effects attributable to gadopentetate dimeglumine were found. Sono-guided needle puncture for the shoulder MR arthrography can be a substitutable method for fluoroscopic guidance, with easy access, advantages of lacking radiation hazard and eliminating the need for iodized contrast agents.

Pt, Co–Pt and Fe–Pt alloy nanoclusters encapsulated in virus capsids

International Nuclear Information System (INIS)

Okuda, M; Eloi, J-C; Jones, S E Ward; Schwarzacher, W; Verwegen, M; Cornelissen, J J L M

2016-01-01

Nanostructured Pt-based alloys show great promise, not only for catalysis but also in medical and magnetic applications. To extend the properties of this class of materials, we have developed a means of synthesizing Pt and Pt-based alloy nanoclusters in the capsid of a virus. Pure Pt and Pt-alloy nanoclusters are formed through the chemical reduction of [PtCl 4 ] − by NaBH 4 with/without additional metal ions (Co or Fe). The opening and closing of the ion channels in the virus capsid were controlled by changing the pH and ionic strength of the solution. The size of the nanoclusters is limited to 18 nm by the internal diameter of the capsid. Their magnetic properties suggest potential applications in hyperthermia for the Co–Pt and Fe–Pt magnetic alloy nanoclusters. This study introduces a new way to fabricate size-restricted nanoclusters using virus capsid. (paper)

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.

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.

Determination of the Pt spin diffusion length by spin-pumping and spin Hall effect

Energy Technology Data Exchange (ETDEWEB)

Zhang, Wei; Pearson, John E.; Hoffmann, Axel [Materials Science Division, Argonne National Laboratory, Argonne, Illinois 60439 (United States); Vlaminck, Vincent [Materials Science Division, Argonne National Laboratory, Argonne, Illinois 60439 (United States); Colegio de Ciencias e Ingenería, Universidad San Fransciso de Quito, Quito (Ecuador); Divan, Ralu [Center for Nanoscale Materials, Argonne National Laboratory, Illinois 60439 (United States); Bader, Samuel D. [Materials Science Division, Argonne National Laboratory, Argonne, Illinois 60439 (United States); Center for Nanoscale Materials, Argonne National Laboratory, Illinois 60439 (United States)

2013-12-09

The spin diffusion length of Pt at room temperature and at 8 K is experimentally determined via spin pumping and spin Hall effect in permalloy/Pt bilayers. Voltages generated during excitation of ferromagnetic resonance from the inverse spin Hall effect and anisotropic magnetoresistance effect were investigated with a broadband approach. Varying the Pt layer thickness gives rise to an evolution of the voltage line shape due to the superposition of the above two effects. By studying the ratio of the two voltage components with the Pt layer thickness, the spin diffusion length of Pt can be directly extracted. We obtain a spin diffusion length of ∼1.2 nm at room temperature and ∼1.6 nm at 8 K.

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

International Nuclear Information System (INIS)

Tirman, P.F.J.; Steinbach, L.S.; Feller, J.F.; Stauffer, A.E.

1996-01-01

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

Magnetic properties of the alloy system Fe-Pt. Bulk materials and nanoparticles; Magnetische Eigenschaften des Legierungssystems Fe-Pt. Volumenmaterialien und Nanopartikel

Energy Technology Data Exchange (ETDEWEB)

Antoniak, C.

2007-12-14

Besides the determination of magnetic properties of epitaxial grown Fe{sub x}Pt{sub 1-x} films like e.g. the magnetic anisotropy, effective magnetisation, exchange length and damping as reference data, wet-chemically synthesised spherical Fe{sub x}Pt{sub 1-x} nanoparticles with different sizes, compositions and crystal structures were examined systematically after the reduction of Fe oxides by a hydrogen plasma treatment. Organic ligands surrounding the particles after the synthesis, were removed as well during this procedure. These ligands prevent the agglomeration of the nanoparticles when deposited onto a substrate, but do not have any measurable effect on the oxide formation under air exposure and do not change the magnetic properties of oxidised nanoparticles within experimental error bars. Static and dynamic magnetic properties were determined using the ferromagnetic resonance technique and themeasurement of the x-ray absorption, especially the analysis of the X-ray circular dichroism. The analysis of the element-specific magnetic moments shows that the effective magnetic spin moment ({mu}{sup eff}{sub s}) of the Fe{sub x}Pt{sub 1-x} nanoparticles is reduced by 20.30% with respect to the one of the corresponding Fe{sub x}Pt{sub 1-x} film due to the inhomogeneous composition within the nanoparticles which was found by the analysis of the extended X-ray absorption fine structure. With decreasing particle size, {mu}{sup eff}{sub s} is further decreasing while the ratio of orbital-to-effective-spin magnetic moment ({mu}{sub l}/{mu}{sup eff}{sub s}) increases. Annealing at 600 C of a sample consisting of Fe{sub 0.50}Pt{sub 0.50} nanoparticles with a mean diameter around 6 nm yields a strong increase of the {mu}{sub l}/{mu}{sup eff}{sub s} ratio at the Fe sites: it reaches a value of about 9% and is as large as the value at the Pt sites. This is accompanied by an enhancement of the coercive field from (36{+-}5) mT to (292{+-}8) mT after annealing that can be

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.)

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

The detection of the capsular tear at the undersurface of the extensor carpi radialis brevis tendon in chronic tennis elbow: the value of magnetic resonance imaging and computed tomography arthrography.

Science.gov (United States)

Sasaki, Koichi; Tamakawa, Mitsuharu; Onda, Kazunori; Iba, Kosuke; Sonoda, Tomoko; Yamashita, Toshihiko; Wada, Takuro

2011-04-01

This study compared the diagnostic efficacy of magnetic resonance imaging (MRI) and computed tomography arthrography (CTA) in the assessment of capsular tears at the undersurface of the extensor carpi radials brevis tendon in chronic tennis elbow using arthroscopy as a gold standard. Because of the higher spatial resolution of CT, we hypothesized that CTA is superior to MRI for assessing capsular tears. We retrospectively reviewed 19 consecutive patients with chronic tennis elbow with preoperative MRI and CTA studies who underwent arthroscopic surgery. Three observers with different levels of training and experience (musculoskeletal radiologist, experienced elbow surgeon, and hand fellow) evaluated the capsular tear by MRI and CTA in a blinded manner. The results of the MRI and CTA were compared and the agreement among the 3 observers was determined using an intraclass correlation coefficient (ICC). Then, the results of the MRI and CTA examinations were compared with the intraoperative findings of the arthroscopic examination. The sensitivity, specificity, and κ value were calculated. The ICC of CTA (0.855) was superior to MRI (0.645). The sensitivity, specificity, and κ value of CTA were superior to those of MRI in each of the 3 observers. The κ value was 0.79, 0.89, and 0.79 for CTA, and 0.48, 0.48, and 0.27 for MRI for the radiologist, surgeon, and fellow, respectively. CTA was a reliable and accurate diagnostic modality compared with MRI to detect the capsular tear in patients with chronic tennis elbow. CTA was less influenced by the observer's experience. Copyright © 2011 Journal of Shoulder and Elbow Surgery Board of Trustees. Published by Mosby, Inc. All rights reserved.

Giant resonances in heavy-ion reactions

International Nuclear Information System (INIS)

Hussein, M.S.

1982-11-01

The several roles of multipole giant resonances in heavy-ion reactions are discussed. In particular, the modifications in the effective ion-ion potencial due to the virtual excitation of giant resonances at low energies, are considered and estimated for several systems. Real excitation of giant resonances in heavy-ion reactions at intermediate energies are then discussed and their importance in the approach phase of deeply inelastic processes in emphasized. Several demonstrative examples are given. (Author) [pt

Systematic continuum-discretized coupled-channels calculations of total fusion for 6Li with targets 28Si, 59Co, 96Zr, 198Pt, and 209Bi: Effect of resonance states

Science.gov (United States)

Gómez Camacho, A.; Wang, Bing; Zhang, H. Q.

2018-05-01

Continuum discretized coupled-channel (CDCC) calculations of total fusion cross sections for reactions induced by the weakly bound nucleus 6Li with targets 28Si, 59Co, 96Zr, 198Pt, and 209Bi at energies around the Coulomb barrier are presented. In the cluster structure frame of 6Li→α +d , short-range absorption potentials are considered for the interactions between the α and d fragments with the targets. The effect of resonance (l =2 , Jπ=3+,2+,1+ ) and nonresonance states of 6Li on fusion is studied by using two approaches: (1) by omitting the resonance states from the full discretized CDCC breakup space and (2) by considering only the resonance subspace. A systematic analysis of the effect on fusion from resonance breakup couplings is carried out from light to heavy mass targets. Among other things, it is found that resonance breakup states produce strong repulsive polarization potentials that lead to fusion suppression. Couplings from nonresonance states give place to weak repulsive potentials at high energies; however, these become attractive for the heavier targets at low energies.

Ultra-high resolution C-Arm CT arthrography of the wrist: Radiation dose and image quality compared to conventional multidetector computed tomography

Energy Technology Data Exchange (ETDEWEB)

Werncke, Thomas, E-mail: Werncke.Thomas@mh-hannover.de [Institute of Diagnostic and Interventional Radiology, Hannover Medical School, Carl-Neuberg-Str. 1, 30625 Hannover (Germany); Sonnow, Lena; Meyer, Bernhard C. [Institute of Diagnostic and Interventional Radiology, Hannover Medical School, Carl-Neuberg-Str. 1, 30625 Hannover (Germany); Lüpke, Matthias [University of Veterinary Medicine Hannover, Institute for General Radiology and Medical Physics, Bischofsholer Damm 15, 30173 Hannover (Germany); Hinrichs, Jan; Wacker, Frank K.; Falck, Christian von [Institute of Diagnostic and Interventional Radiology, Hannover Medical School, Carl-Neuberg-Str. 1, 30625 Hannover (Germany)

2017-04-15

Objective: Objective of this phantom and cadaveric study was to compare the effective radiation dose (ED) and image quality (IQ) between C-arm computed tomography (CACT) using an ultra-high resolution 1 × 1 binning with a standard 16-slice CT (MDCT) arthrography of the wrist. Methods: ED was determined with thermoluminescence dosimetry using an anthropomorphic phantom and different patient positions. Imaging was conducted in 10 human cadaveric wrists after tri-compartmental injection of diluted iodinated contrast material and a wire phantom. IQ of MDCT was compared with CACT reconstructed with a soft (CACT1) and sharp (CACT2) kernel. High and low contrast resolution was determined. Three radiologists assessed IQ of wrist structures and occurrence of image artifacts using a 5-point Likert scale. Results: ED of MDCT was comparable to standard CACT (4.3 μSv/3.7 μSv). High contrast resolution was best for CACT2, decreased to CACT1 and MDCT. Low contrast resolution increased between CACT2 and MDCT (P < 0.001). IQ was best for CACT2 (1.3 ± 0.5), decreased to CACT1 (1.9 ± 0.6) and MDCT (3.5 ± 0.6). Non-compromising artifacts were only reported for CACT. Conclusions: The results of this phantom and cadaveric study indicate that ultra-high resolution C-Arm CT arthrography of the wrist bears the potential to outperform MDCT arthrography in terms of image quality and workflow at the cost of mildly increasing image artifacts while radiation dose to the patient is comparably low for both, MDCT and C-Arm CT.

Statistical decay of giant resonances

International Nuclear Information System (INIS)

Dias, H.; Teruya, N.; Wolynec, E.

1986-01-01

Statistical calculations to predict the neutron spectrum resulting from the decay of Giant Resonances are discussed. The dependence of the resutls on the optical potential parametrization and on the level density of the residual nucleus is assessed. A Hauser-Feshbach calculation is performed for the decay of the monople giant resonance in 208 Pb using the experimental levels of 207 Pb from a recent compilation. The calculated statistical decay is in excelent agreement with recent experimental data, showing that the decay of this resonance is dominantly statistical, as predicted by continuum RPA calculations. (Author) [pt

Statistical decay of giant resonances

International Nuclear Information System (INIS)

Dias, H.; Teruya, N.; Wolynec, E.

1986-02-01

Statistical calculations to predict the neutron spectrum resulting from the decay of Giant Resonances are discussed. The dependence of the results on the optical potential parametrization and on the level density of the residual nucleus is assessed. A Hauser-Feshbach calculation is performed for the decay of the monopole giant resonance in 208 Pb using the experimental levels of 207 Pb from a recent compilation. The calculated statistical decay is in excellent agreement with recent experimental data, showing that decay of this resonance is dominantly statistical, as predicted by continuum RPA calculations. (Author) [pt

Arthrography

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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) - ...

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.

Arthrography

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Full Text Available ... bear denotes child-specific content. Related Articles and Media Magnetic Resonance Imaging (MRI) - Musculoskeletal Radiation Dose in ... the web pages found at these links. About Us | Contact Us | FAQ | Privacy | Terms of Use | Links | ...

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 ... have special pediatric considerations. The teddy bear denotes child-specific content. Related Articles and Media Magnetic Resonance ...

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 ... have special pediatric considerations. The teddy bear denotes child-specific content. Related Articles and Media Magnetic Resonance ...

Examination of the sprained ankle: Anterior drawer test or arthrography

Energy Technology Data Exchange (ETDEWEB)

Laehde, S.; Putkonen, M.; Puranen, J.; Raatikainen, T.

1988-11-01

The accuracy of the anterior drawer test for the diagnosis of recent lateral ligament tears in the ankle was evaluated in a series of 192 patients using surgical or arthrographic findings for reference. Considerable overlapping of results was obtained in ankles with and without ligament tear. Twenty-eight per cent of the anterior talofibular ligament tears, and 38% of the combined anterior talofibular and calcaneofibular tears were not detected, and single and combined tears could not be differentiated. It is concluded that the anterior drawer test is too unreliable as a basis for any decision regarding surgical treatment of a recent sprain. Therefore, arthrography is recommended as the method of choice in such cases of recent ankle sprain, where the need of surgery has to be supported by X-ray analysis.

Examination of the sprained ankle: Anterior drawer test or arthrography?

International Nuclear Information System (INIS)

Laehde, S.; Putkonen, M.; Puranen, J.; Raatikainen, T.

1988-01-01

The accuracy of the anterior drawer test for the diagnosis of recent lateral ligament tears in the ankle was evaluated in a series of 192 patients using surgical or arthrographic findings for reference. Considerable overlapping of results was obtained in ankles with and without ligament tear. Twenty-eight per cent of the anterior talofibular ligament tears, and 38% of the combined anterior talofibular and calcaneofibular tears were not detected, and single and combined tears could not be differentiated. It is concluded that the anterior drawer test is too unreliable as a basis for any decision regarding surgical treatment of a recent sprain. Therefore, arthrography is recommended as the method of choice in such cases of recent ankle sprain, where the need of surgery has to be supported by X-ray analysis. (orig.)

Arthrography

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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 ...

Electronic structures of PtCu, PtAg, and PtAu molecules: a Dirac four-component relativistic study

International Nuclear Information System (INIS)

Abe, Minori; Mori, Sayaka; Nakajima, Takahito; Hirao, Kimihiko

2005-01-01

Relativistic four-component calculations at several correlated levels have been performed for diatomic PtCu, PtAg, and PtAu molecules. The ground state spectroscopic constants of PtCu were calculated using the four-component MP2 method, and show good agreement with experiment. We also performed calculations on the experimentally unknown species, PtAg and PtAu, and the mono-cationic systems, PtCu + , PtAg + , and PtAu + . The low-lying excited states of these diatomic molecules were also investigated using the four-component multi-reference CI method

Decay of giant resonance E2 isoscalar in heavy nuclei

International Nuclear Information System (INIS)

Herdade, S.B.

1980-01-01

In this work, it is made a study of the giant resonance E2 isoscalar, in heavy nuclei. Fission probabilities for this resonance were determined by various authors, in different experiments, for 238 U. (A.C.A.S.) [pt

Frequency and magnetic field mapping of magnetoelastic spin pumping in high overtone bulk acoustic wave resonator

Science.gov (United States)

Polzikova, N. I.; Alekseev, S. G.; Pyataikin, I. I.; Luzanov, V. A.; Raevskiy, A. O.; Kotov, V. A.

2018-05-01

We report on the first observation of microvolt-scale inverse spin Hall effect (ISHE) dc voltage driven by an acoustic spin pumping (ASP) in a bulk acoustic wave (BAW) resonator formed by a Al-ZnO-Al-YIG(1)-GGG-YIG(2)-Pt structure. When 2 mW power is applied to an Al-ZnO-Al transducer, the voltage VISHE ˜ 4 μV in the Pt film is observed as a result of resonant ASP from YIG(2) to Pt in the area ˜ 170 μm. The results of frequency and magnetic field mapping of VISHE(f,H) together with reflectivity of the resonator show an obvious agreement between the positions of the voltage maxima and BAW resonance frequencies fn(H) on the (f, H) plane. At the same time a significant asymmetry of the VISHE(fn(H)) value in reference to the magnetoelastic resonance (MER) line fMER(H) position is revealed, which is explained by asymmetry of the magnetoelastic waves dispersion law.

Arthrography

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Full Text Available ... resonance imaging (MRI) or fluoroscopy – a form of real-time x-ray. Your preparation may vary depending on ... to see bones, joints and internal organs in real time. When iodine contrast is injected into the joint, ...

Superconducting properties and pseudogap from preformed Cooper pairs in the triclinic (CaFe{sub 1-x}Pt{sub x}As){sub 10}Pt{sub 3}As{sub 8}

Energy Technology Data Exchange (ETDEWEB)

Surmach, M.A.; Brueckner, F.; Kamusella, S.; Sarkar, R.; Portnichenko, P.Y.; Klauss, H.H.; Inosov, D.S. [TU Dresden (Germany); Park, J.T. [MLZ, Garching (Germany); Ghambashidze, G. [MPI, Stuttgart (Germany); Luetkens, H.; Biswas, P. [PSI, Villigen (Switzerland); Choi, W.J.; Seo, Y.I.; Kwon, Y.S. [DGIST, Daegu (Korea, Republic of)

2015-07-01

Using μSR, INS and NMR, we investigated the novel Fe-based superconductor with a triclinic crystal structure (CaFe{sub 1-x}Pt{sub x}As){sub 10}Pt{sub 3}As{sub 8} (T{sub c}=13 K). The T-dependence of the superfluid density from the μSR measurements indicates the presence of two superconducting gaps. Our INS data revealed commensurate spin fluctuations at the (π, 0) wave vector. Their intensity remains unchanged across T{sub c}, indicating the absence of a spin resonance typical for many Fe-pnictides. Instead, we observed a peak around ℎω{sub 0} = 7 meV at the same wave vector, which persists above T{sub c} and is characterized by the ratio ℎω{sub 0}/k{sub B}T{sub c}∼6.2, i.e. significantly higher than typical values for the magnetic resonant modes in iron pnictides (∝ 4.3). The T-dependence of magnetic intensity at 7 meV revealed an anomaly around T*=45 K related to the disappearance of this new mode. A suppression of the spin-lattice relaxation rate, 1=/T{sub 1}T, observed by NMR immediately below T* without any notable subsequent anomaly at T{sub c}, indicates that T{sup *} could mark the onset of a pseudogap in (CaFe{sub 1-x}Pt{sub x}As){sub 10}Pt{sub 3}As{sub 8}, likely associated with the emergence of preformed Cooper pairs.

Shoulder arthrography: A study for the correlation of anatomy and radiology

International Nuclear Information System (INIS)

Sung, K. J.; Kim, I. Y.; Park, C. Y.

1983-01-01

Shoulder arthrogram and dissection in cadaver were performed for clinical application. Puncture site for contrast injection was studied. The results were as follows: 1. Shoulder joints is located above the axillar and arthrography of shoulder is a simple, safe and easily interpreted. 2. The land mark for injection is a point 1.5 cm below the tip of coracoid process and very slightly medial to it. 3. There were contrast material leak from subscapular recess and distal end of the synovial sheath surrounding the long head of the biceps tendon in normal shoulder arthrogram. 4. Synoviad cavity margin show smoothness and no abnormal filling defect. 5. There were no communication between synovial cavity and subdeltoid bursa. 6. There were no specific anatomic variation in shoulder joint

Preparation of PtSn/C, PtRu/C, PtRh/C, PtRuRh/C and PtSnRh/C electrocatalysts using an alcohol-reduction process for methanol and ethanol oxidation; Preparacao e caracterizacao de eletrocatalisadores PtRu, PtSn, PtRh, PtRuRh e PtSnRh para oxidacao direta de alcoois em celulas a combustivel tipo PEM utilizando a metodologia da reducao por alcool

Energy Technology Data Exchange (ETDEWEB)

Dias, Ricardo Rodrigues

2009-07-01

In this work, Pt/C, PtRh (90:10), PtRh/C (50:50), PtSn/C (50:50), PtRu (50:50)/C, PtRuRh/C (50:40:10) and PtSnRh/C (50:40:10) were prepared by an alcohol-reduction process with metal loading of 20 wt.% using H{sub 2}PtCl{sub 6}.6H{sub 2}O (Aldrich), SnCl{sub 2}.2H{sub 2}O (Aldrich),and RhCl{sub 2}.XH{sub 2}O (Aldrich) as metals sources and Vulcan XC72 as support. The electrocatalysts were characterized by EDX, XRD and cyclic voltammetry (CV). The electro-oxidation of ethanol was studied by CV, chronoamperomety at room temperature in acid medium and tests at 100 deg C on a single cell of a direct methanol or ethanol fuel cell. The EDX analysis showed that the metal atomic ratios of the obtained electrocatalysts were similar to the nominal atomic ratios used in the preparation. The diffractograms of electrocatalysts prepared showed four peaks at approximately 2{theta} =40 deg, 47 deg, 67 deg and 82 deg, which are associated with the (111), (200), (220) and (311) planes, respectively, of a face cubic-centered (fcc) structure characteristic of platinum and platinum alloys. The average crystallite sizes using the Scherrer equation and the calculated values were in the range of 2-3 nm. For Pt Sn/C and PtSnRh/C two additional peaks were observed at 2 = 34 deg and 52 deg that were identified as a SnO{sub 2} phase. Pt Sn/C (50:50) and PtSnRh/C (50:40:10) electro catalyst showed the best performance for ethanol oxidation at room temperature. For methanol oxidation at room temperature Pt Ru/C, Pt Sn/C and PtRuRh/C electrocatalysts showed the best performance. Tests at 100 deg C on a single cell of a direct ethanol fuel cell PtSnRh/C showed the best performance, for methanol oxidation PtRuRh/C showed the best performance. (author)

Articular cartilage and labral lesions of the glenohumeral joint: diagnostic performance of 3D water-excitation true FISP MR arthrography

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Dietrich, Tobias Johannes [Orthopedic University Hospital Balgrist, Department of Radiology, Zurich (Switzerland); Kantonsspital Muensterlingen, Department of Radiology, PO Box 8596, Muensterlingen (Switzerland); Zanetti, Marco; Saupe, Nadja; Pfirrmann, Christian W.A.; Hodler, Juerg [Orthopedic University Hospital Balgrist, Department of Radiology, Zurich (Switzerland); Fucentese, Sandro F. [Hospital Balgrist, Department of Orthopedic Surgery, Orthopedic University, Zurich (Switzerland)

2010-05-15

To evaluate the diagnostic performance of MR arthrography in the detection of articular cartilage and labral lesions of the glenohumeral joint using a transverse 3D water-excitation true fast imaging with steady-state precession (FISP) sequence. Seventy-five shoulders were included retrospectively. Shoulder arthroscopy was performed within 6 months of MR arthrography. MR images were evaluated separately by two radiologists. They were blinded to clinical and arthroscopic information. Arthroscopy served as the reference standard. For the detection of humeral cartilage lesions, sensitivities and specificities were 86% (12/14)/89% (50/56) for observer 1 and 93%/86% for observer 2) for the transverse true FISP sequence and 64%/86% (50%/82% for observer 2) for the coronal intermediate-weighted spin-echo images. The corresponding values for the glenoidal cartilage were 60% (6/10)/88% (51/58) (80%/76% for observer 2) and 70%/86% (60%/74% for observer 2) respectively. For the detection of abnormalities of the anterior labrum (only assessed on true FISP images) the values were 94% (15/16)/84% (36/43) (88%/79% for observer 2). The corresponding values for the posterior labrum were 67% (8/12)/77% (36/47) (observer 2: 25%/74%). The kappa values for the grading of the humeral and glenoidal cartilage lesions were 0.81 and 0.55 for true FISP images compared with 0.49 and 0.43 for intermediate-weighted fast spin-echo images. Kappa values for true FISP evaluation of the anterior and posterior part of the labrum were 0.81 and 0.70. Transverse 3D true FISP MR arthrography images are useful for the difficult diagnosis of glenohumeral cartilage lesions and suitable for detecting labral abnormalities. (orig.)

MR appearance of cartilage defects of the knee: preliminary results of a spiral CT arthrography-guided analysis

International Nuclear Information System (INIS)

Berg, B.C. vande; Lecouvet, F.E.; Maldague, B.; Malghem, J.

2004-01-01

The aim of this study was to determine signal intensity patterns of cartilage defects at MR imaging. The MR imaging (3-mm-thick fat-suppressed intermediate-weighted fast spin-echo images) was obtained in 31 knees (21 male and 10 female patients; mean age 45.5 years) blindly selected from a series of 252 consecutive knees investigated by dual-detector spiral CT arthrography. Two radiologists determined in consensus the MR signal intensity of the cartilage areas where cartilage defects had been demonstrated on the corresponding reformatted CT arthrographic images. There were 83 cartilage defects at spiral CT arthrography. In 52 (63%) lesion areas, the MR signal intensity was higher than that of adjacent normal cartilage with signal intensity equivalent to (n=31) or lower than (n=21) that of articular fluid. The MR signal intensity was equivalent to that of adjacent normal cartilage in 17 (20%) lesion areas and lower than that of adjacent cartilage in 8 (10%) lesion areas. In 6 (7%) lesion areas, mixed low and high signal intensity was observed. The MR signal intensity of cartilage defects demonstrated on spiral CT arthrographic images varies from low to high on fat-suppressed intermediate-weighted fast spin-echo MR images obtained with our equipment and MR parameters. (orig.)

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

International Nuclear Information System (INIS)

Kim, Gang Deuk; Kim, Huoung Jun; Kim, Hye Won; Oh, Jung Taek; Juhng, Seon Kwan; Lee, Sung Ah

2007-01-01

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

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

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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.

Gradient-recalled echo sequences in direct shoulder MR arthrography for evaluating the labrum

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Lee, Marc J.; Motamedi, Kambiz; Chow, Kira; Seeger, Leanne L. [David Geffen School of Medicine at UCLA, Department of Radiology, 200 UCLA Medical Plaza, Suite 165-59, Box 956952, Los Angeles, CA (United States)

2008-01-15

The purpose of this study was to determine the utility of fat-suppressed gradient-recalled echo (GRE) compared with conventional spin echo T1-weighted (T1W) sequences in direct shoulder MR arthrography for evaluating labral tears. Three musculoskeletal radiologists retrospectively reviewed MR arthrograms performed over a 12-month period for which surgical correlation was available. Of 180 serial arthrograms, 31 patients had surgery with a mean of 48 days following imaging. Paired coronal oblique and axial T1W or GRE sequences were analyzed by consensus for labral tear (coronal oblique two-dimensional multi-echo data image combination, 2D MEDIC; and axial three-dimensional double-echo steady-state, 3D DESS; Siemens MAGNETOM Sonata 1.5-T MR system). Interpretations were correlated with operative reports. Of 31 shoulders, 25 had labral tears at surgery. The GRE sequences depicted labral tears in 22, while T1W images depicted tears in 16 (sensitivity 88% versus 64%; p < 0.05). Subdividing the labrum, GRE was significantly more sensitive for the posterior labrum (75% versus 25%; p < 0.05) with a trend toward greater sensitivity at the anterior labrum (78% versus 56%; p = 0.157) but not significantly different for the superior labrum (50% versus 57%; p > 0.7). Specificities were somewhat lower for GRE. Thin section GRE sequences are more sensitive than T1W for the detection of anterior and posterior labral tears. As the specificity of GRE was lower, it should be considered as an adjunctive imaging sequence that may improve depiction of labral tears, particularly smaller tears, in routine MR arthrography protocols. (orig.)

Preparation of PtSn/C, PtRu/C, PtRh/C, PtRuRh/C and PtSnRh/C electrocatalysts using an alcohol-reduction process for methanol and ethanol oxidation; Preparacao e caracterizacao de eletrocatalisadores PtRu, PtSn, PtRh, PtRuRh e PtSnRh para oxidacao direta de alcoois em celulas a combustivel tipo PEM utilizando a metodologia da reducao por alcool

Energy Technology Data Exchange (ETDEWEB)

Dias, Ricardo Rodrigues

2009-07-01

In this work, Pt/C, PtRh (90:10), PtRh/C (50:50), PtSn/C (50:50), PtRu (50:50)/C, PtRuRh/C (50:40:10) and PtSnRh/C (50:40:10) were prepared by an alcohol-reduction process with metal loading of 20 wt.% using H{sub 2}PtCl{sub 6}.6H{sub 2}O (Aldrich), SnCl{sub 2}.2H{sub 2}O (Aldrich),and RhCl{sub 2}.XH{sub 2}O (Aldrich) as metals sources and Vulcan XC72 as support. The electrocatalysts were characterized by EDX, XRD and cyclic voltammetry (CV). The electro-oxidation of ethanol was studied by CV, chronoamperomety at room temperature in acid medium and tests at 100 deg C on a single cell of a direct methanol or ethanol fuel cell. The EDX analysis showed that the metal atomic ratios of the obtained electrocatalysts were similar to the nominal atomic ratios used in the preparation. The diffractograms of electrocatalysts prepared showed four peaks at approximately 2θ = 40{sup 0}, 47{sup 0}, 67{sup 0} and 82{sup 0}, which are associated with the (111), (200), (220) and (311) planes, respectively, of a face cubic-centered (fcc) structure characteristic of platinum and platinum alloys. The average crystallite sizes using the Scherrer equation and the calculated values were in the range of 2–3 nm. For PtSn/C and PtSnRh/C two additional peaks were observed at 2θ = 34{sup 0} and 52{sup 0} that were identified as a SnO{sub 2} phase. PtSn/C (50:50) and PtSnRh/C (50:40:10) electrocatalyst showed the best performance for ethanol oxidation at room temperature. For methanol oxidation at room temperature PtRu/C, PtSn/C and PtRuRh/C electrocatalysts showed the best performance. Tests at 100 deg C on a single cell of a direct ethanol fuel cell PtSnRh/C showed the best performance, for methanol oxidation PtRuRh/C showed the best performance. (author)

Infrapatellar plica of the knee: Revisited with MR arthrographies undertaken in the knee flexion position mimicking operative arthroscopic posture

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Lee, Young Han; Song, Ho-Taek; Kim, Sungjun [Department of Radiology and Research Institute of Radiological Science, Yonsei University College of Medicine, 250 Seongsanno, Seodaemun-gu, Seoul 120-752 (Korea, Republic of); Kim, Sung-Jae [Department of Orthopedic Surgery and Arthroscopic Surgery Unit, Yonsei University College of Medicine (Korea, Republic of); Suh, Jin-Suck, E-mail: jss@yuhs.ac [Department of Radiology and Research Institute of Radiological Science, Yonsei University College of Medicine, 250 Seongsanno, Seodaemun-gu, Seoul 120-752 (Korea, Republic of)

2012-10-15

Purpose: To describe the appearance of the infrapatellar plica (IPP) on magnetic resonance arthrography (MRA) taken in 70° knee flexion, corresponding to the arthroscopic posture. Materials and methods: Twenty-two patients (23 knee joints) who underwent MRA with 70° knee flexion were enrolled. All patients underwent MRA with 70° knee flexion to simulate operative arthroscopy. The images included fat-suppressed T1-weighted spin echo axial, sagittal, and coronal images. The visualization and morphology of the IPP were retrospectively assessed by two musculoskeletal radiologists. Results: The IPP was demonstrated in 78.3% (n = 18/23) and was best visualized on the sagittal section through the intercondylar notch. The IPP manifested as a linear hypointense structure with variable thicknesses. The intercondylar component was delineated clearly, arising from the anterior intercondylar notch in parallel with the ACL and curving gently downward to attach to the infrapatellar fat pad. On the other hand, the Hoffa's fat pad component was not depicted clearly. The morphology of the IPP was either a separate type (60.9%) or a split type (17.4%). Conclusion: The IPPs can be visualized with a high rate of detection and various morphologic appearances must be appreciated under the review of a flexed knee MRA.

Arthrography of the lumber facet joint and facet block

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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.

Arthrography of the lumber facet joint and facet block

International Nuclear Information System (INIS)

Cho, Hee Kyung; Chung, Tae Sub; Kim, Young Soo; Park, Hyung Chun; Moon, Jae Ho; Suh, Jung Ho; Kim, Dong Ik

1988-01-01

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.

Preparation of PtSn/C, PtRu/C, PtRh/C, PtRuRh/C and PtSnRh/C electrocatalysts using an alcohol-reduction process for methanol and ethanol oxidation

International Nuclear Information System (INIS)

Dias, Ricardo Rodrigues

2009-01-01

In this work, Pt/C, PtRh (90:10), PtRh/C (50:50), PtSn/C (50:50), PtRu (50:50)/C, PtRuRh/C (50:40:10) and PtSnRh/C (50:40:10) were prepared by an alcohol-reduction process with metal loading of 20 wt.% using H 2 PtCl 6 .6H 2 O (Aldrich), SnCl 2 .2H 2 O (Aldrich),and RhCl 2 .XH 2 O (Aldrich) as metals sources and Vulcan XC72 as support. The electrocatalysts were characterized by EDX, XRD and cyclic voltammetry (CV). The electro-oxidation of ethanol was studied by CV, chronoamperomety at room temperature in acid medium and tests at 100 deg C on a single cell of a direct methanol or ethanol fuel cell. The EDX analysis showed that the metal atomic ratios of the obtained electrocatalysts were similar to the nominal atomic ratios used in the preparation. The diffractograms of electrocatalysts prepared showed four peaks at approximately 2θ = 40 0 , 47 0 , 67 0 and 82 0 , which are associated with the (111), (200), (220) and (311) planes, respectively, of a face cubic-centered (fcc) structure characteristic of platinum and platinum alloys. The average crystallite sizes using the Scherrer equation and the calculated values were in the range of 2–3 nm. For PtSn/C and PtSnRh/C two additional peaks were observed at 2θ = 34 0 and 52 0 that were identified as a SnO 2 phase. PtSn/C (50:50) and PtSnRh/C (50:40:10) electrocatalyst showed the best performance for ethanol oxidation at room temperature. For methanol oxidation at room temperature PtRu/C, PtSn/C and PtRuRh/C electrocatalysts showed the best performance. Tests at 100 deg C on a single cell of a direct ethanol fuel cell PtSnRh/C showed the best performance, for methanol oxidation PtRuRh/C showed the best performance. (author)

Arthrography of the traumatized wrist: correlation with radiography and the carpal instability series

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Levinsohn, E.M.; Palmer, A.K.

1983-03-01

Arthrography with fluoroscopic monitoring was used to assess the soft tissues of the wrist in 100 patients who had chronic traumatic pain but did not have rheumatoid arthritis. Findings were correlated with plain radiographs and the carpal instability series. Arthrograms were normal in 26% of cases and demonstrated perforation of the triangular fibrocartilage in 26%, radiocarpal-midcarpal communication in 30%, capsular lesions in 31%, lymphatic opacification in 12%, and tendon sheath filling in 10%. Communication between the radiocarpal and pisiform-troiquetral compartments, a normal finding, was seen in 69%. There was a significant association between perforation of the triangular fibrocartilage and both ulna-plus variance and carpal instability.

Frequency and magnetic field mapping of magnetoelastic spin pumping in high overtone bulk acoustic wave resonator

Directory of Open Access Journals (Sweden)

N. I. Polzikova

2018-05-01

Full Text Available We report on the first observation of microvolt-scale inverse spin Hall effect (ISHE dc voltage driven by an acoustic spin pumping (ASP in a bulk acoustic wave (BAW resonator formed by a Al-ZnO-Al-YIG(1-GGG-YIG(2-Pt structure. When 2 mW power is applied to an Al-ZnO-Al transducer, the voltage VISHE ∼ 4 μV in the Pt film is observed as a result of resonant ASP from YIG(2 to Pt in the area ∼ 170 μm. The results of frequency and magnetic field mapping of VISHE(f,H together with reflectivity of the resonator show an obvious agreement between the positions of the voltage maxima and BAW resonance frequencies fn(H on the (f, H plane. At the same time a significant asymmetry of the VISHE(fn(H value in reference to the magnetoelastic resonance (MER line fMER(H position is revealed, which is explained by asymmetry of the magnetoelastic waves dispersion law.

Comparative reliability and diagnostic performance of conventional 3T magnetic resonance imaging and 1.5T magnetic resonance arthrography for the evaluation of internal derangement of the hip

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Chopra, A. [Chapel Allerton Hospital, Radiology Department, Leeds Teaching Hospitals, Leeds (United Kingdom); Grainger, A.J.; Robinson, Philip [Chapel Allerton Hospital, Radiology Department, Leeds Teaching Hospitals, Leeds (United Kingdom); Chapel Allerton Hospital, University of Leeds and NHIR Leeds Musculoskeletal Biomedical Research Centre, Leeds (United Kingdom); Dube, B.; Evans, R.; Hodgson, R. [Chapel Allerton Hospital, University of Leeds and NHIR Leeds Musculoskeletal Biomedical Research Centre, Leeds (United Kingdom); Conroy, J. [Harrogate and District NHS Trust, Trauma and Orthopaedics Department, Harrogate (United Kingdom); Macdonald, D. [Chapel Allerton Hospital, Trauma and Orthopaedics Department, Leeds Teaching Hospitals, Leeds (United Kingdom)

2018-03-15

To compare the diagnostic accuracy of conventional 3T MRI against 1.5T MR arthrography (MRA) in patients with clinical femoroacetabular impingement (FAI). Sixty-eight consecutive patients with clinical FAI underwent both 1.5T MRA and 3T MRI. Imaging was prospectively analysed by two musculoskeletal radiologists, blinded to patient outcomes and scored for internal derangement including labral and cartilage abnormality. Interobserver variation was assessed by kappa analysis. Thirty-nine patients subsequently underwent hip arthroscopy and surgical results and radiology findings were analysed. Both readers had higher sensitivities for detecting labral tears with 3T MRI compared to 1.5T MRA (not statistically significant p=0.07). For acetabular cartilage defect both readers had higher statistically significant sensitivities using 3T MRI compared to 1.5T MRA (p=0.02). Both readers had a slightly higher sensitivity for detecting delamination with 1.5T MRA compared to 3T MRI, but these differences were not statistically significant (p=0.66). Interobserver agreement was substantial to perfect agreement for all parameters except the identification of delamination (3T MRI showed moderate agreement and 1.5T MRA substantial agreement). Conventional 3T MRI may be at least equivalent to 1.5T MRA in detecting acetabular labrum and possibly superior to 1.5T MRA in detecting cartilage defects in patients with suspected FAI. circle Conventional 3T MRI is equivalent to 1.5T MRA for diagnosing labral tears. (orig.)

Localized-Surface-Plasmon Enhanced the 357 nm Forward Emission from ZnMgO Films Capped by Pt Nanoparticles

Directory of Open Access Journals (Sweden)

Song XM

2009-01-01

Full Text Available Abstract The Pt nanoparticles (NPs, which posses the wider tunable localized-surface-plasmon (LSP energy varying from deep ultraviolet to visible region depending on their morphology, were prepared by annealing Pt thin films with different initial mass-thicknesses. A sixfold enhancement of the 357 nm forward emission of ZnMgO was observed after capping with Pt NPs, which is due to the resonance coupling between the LSP of Pt NPs and the band-gap emission of ZnMgO. The other factors affecting the ultraviolet emission of ZnMgO, such as emission from Pt itself and light multi-scattering at the interface, were also discussed. These results indicate that Pt NPs can be used to enhance the ultraviolet emission through the LSP coupling for various wide band-gap semiconductors.

Deep-level defects in semiconductors: studies by magnetic resonance

International Nuclear Information System (INIS)

Ammerlaan, C.A.J.

1983-01-01

This work is divided into two parts. In the first one, the following topics are discussed: paramagnetic centers in semiconductors, principles of magnetic resonance, spin-Hamiltonian, g-tensor, hyperfine interaction, magnetic resonance spectrometer. In the second part it is dicussed defects studied by magnetic resonance including vacancy and divacancy in silicon, iron in silicon, nitrogen in diamond and antisite defects in III-V compounds. (A.C.A.S.) [pt

CT arthrography of the wrist using a novel, mobile, dedicated extremity cone-beam CT (CBCT)

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Koskinen, Seppo K. [Helsinki University Central Hospital, Department of Radiology, HUS Helsinki Medical Imaging Center, Helsinki (Finland); Helsinki University Hospital, Toeoeloe Trauma Center, Department of Radiology, HUS Helsinki Medical Imaging Center, Helsinki (Finland); Haapamaeki, Ville V.; Kortesniemi, Mika [Helsinki University Central Hospital, Department of Radiology, HUS Helsinki Medical Imaging Center, Helsinki (Finland); Salo, Jari [Helsinki University Central Hospital, Department of Orthopedic and Trauma Surgery, Helsinki (Finland); Kuopio University Hospital, UEF, Department of Orthopedics, Traumatology and Hand Surgery, Kuopio (Finland); Lindfors, Nina C. [Helsinki University Central Hospital, Department of Orthopedic and Hand Surgery, Helsinki (Finland); Seppaelae, Lauri [Planmed Oy, Helsinki (Finland); Mattila, Kimmo T. [Turku University Central Hospital, Department of Diagnostic Radiology, Turku (Finland)

2013-05-15

To evaluate the feasibility and intra- and interobserver agreement of CBCT arthrography of wrist ligaments, triangular fibrocartilaginous complex (TFCC), and to assess the sensitivity (SE), specificity (SP), accuracy (ACC), and positive and negative predictive value (PPV, NPV) of CBCT arthrography in the diagnosis of scapholunate (SLL) and lunotriquetral (LTL) ligament tears, TFCC, and cartilage abnormalities of the scaphoid and lunate with their corresponding radial surfaces (scaphoid and lunate fossa) using a novel, mobile, dedicated extremity CBCT scanner. Fifty-two consecutively enrolled subjects (26 M, 26 F, mean age 38 years, range 18-66 years) with suspected wrist ligament tears underwent CBCT-arthrography before normally scheduled MR arthrography.An extremity CBCT was used for imaging with isotropic voxel size of 0.4 x 0.4 x 0.4 mm{sup 3}. Subsequent routine 1.5 T MRI was performed using a dedicated wrist coil.Two observers reviewed the anonymized CBCT images twice for contrast enhancement (CE) and technical details (TD), for tears of the SLL, LTL, and TFCC. Also, cartilage abnormalities of the scaphoid and lunate with their corresponding radial surfaces (scaphoid and lunate fossa) were evaluated. Inter- and intraobserver agreement was determined using weighted kappa statistics. Since no surgery was performed, MRI served as a reference standard, and SE and SP, ACC, PPV, and NPV were calculated. Intra- and interobserver kappa values for both readers (reader 1/reader 2; first reading/second reading) with 95 % confidence limits were: CE 0.54 (0.08-1.00)/ 0.75 (0.46-1.00); 0.73 (0.29-1.00)/ 0.45 (0.07-0.83), TD 0.53 (0.30-0.88)/ 0.86 (0.60-1.00); 0.56 (0.22-0.91)/ 0.67 (0.37-0.98), SLL 0.59 (0.25-0.93)/ 0.66 (0.42-0.91); 0.31 (0.06-0.56)/ 0.49 (0.26-0.73), LTL 0.83 (0.66-1.00)/ 0.68 (0.46-0.91); 0.90 (0.79-1.00)/ 0.48 (0.22-0.74); TFCC (0.72-1.00)/ (0.79-1.00); 0.65 (0.43-0.87)/ 0.59 (0.35-0.83), radius (scaphoid fossa) 0.45 (0.12-0.77)/ 0.64 (0.31-0.96); 0

Processing and thin film formation of TiO{sub 2}-Pt nanocomposites

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Es-Souni, M.; Kartopu, G.; Habouti, S.; Piorra, A.; Solterbeck, C.H. [Institute for Materials and Surface Technology, Kiel University of Applied Sciences, Grenzstr. 3, 24149 Kiel (Germany); Es-Souni, Mar.; Brandies, H.F. [Faculty of Dentistry, Christian-Albrecht University, Kiel (Germany)

2008-02-15

Thin films of TiO{sub 2}-Pt nanocomposites containing 4 at% Pt have been processed via spin-coating. Film characterization involved XRD, Raman as well as XPS and scanning surface potential microscopy (SSPM). After annealing at 500 C the thin films consisted of nanocrystalline anatase and a few nm Pt nanoclusters. Annealing at 600 C resulted in the formation of a high volume fraction of rutile, {proportional_to}70%, and a coarsening of the microstructure, including Pt nanoparticles which attained a mean particle size of up to 11 nm. These results contrasted with those of pure TiO{sub 2} films obtained at 600 C which showed only a limited amount of rutile formation, namely 9%. Raman spectra of Pt-containing samples exhibited a fluorescence emission, as background to the Raman features, which was attributed to photoinduced luminescence from Pt nanoparticles supported by their surface plasmon resonance. Emission intensity being much higher in 600 C film indicated a difference between the two films in terms of the (Pt) particle size and crystallinity, in agreement with the XRD results. XPS investigations revealed different oxidation states of Pt at the surface and in the film interior. The spectra suggested a slight oxidation of Pt at the surface while mainly metallic Pt was revealed in the film interior. The morphology and distribution of the Pt nanoparticles in the films annealed at 600 C were investigated using SSPM. Discrete Pt nanoparticles, mainly distributed in the vicinity of TiO{sub 2} grain boundaries were revealed. Nanocomposite film formation, Pt distribution and morphology are explained in terms of the limited solubility of Pt in the TiO{sub 2} lattice and its higher surface energy in comparison to that of TiO{sub 2}. Both effects are believed to lead to the formation of Pt nanoparticles at the (anatase or rutile) grain boundaries. (copyright 2008 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim) (orig.)

Wrist arthrography: The value of the three compartment injection technique

Energy Technology Data Exchange (ETDEWEB)

Levinsohn, E.M.; Coren, A.B.; Palmer, A.K.; Zinberg, E.

1987-10-01

Arthrography of the wrist was performed on 50 consecutive patients with obscure post-traumatic wrist pain by injecting contrast separately into the radiocarpal joint, midcarpal compartment, and distal radioulnar joint. When distal radioulnar joint and midcarpal compartment injections were added to the standard radiocarpal injection, many significant unsuspected abnormalities were identified. Of the 25 triangular fibrocartilage complex abnormalities identified, six (24%) were found only with the distal radioulnar joint injection. Of the 29 abnormal communications between the midcarpal compartment and the radiocarpal joint, ten (35%) were found only with the midcarpal injection. Similarly, five of 29 (17%) of the abnormal radiocarpal-midcarpal communications would have been missed if a midcarpal injection alone had been performed. These findings indicate that separate injections into the radiocarpal joint, midcarpal compartment, and distal radioulnar joint are needed to identify a large number of abnormalities not seen with injections into one compartment alone.

Ultrastrong extraordinary transmission and reflection in PT-symmetric Thue-Morse optical waveguide networks.

Science.gov (United States)

Wu, Jiaye; Yang, Xiangbo

2017-10-30

In this paper, we construct a 1D PT-symmetric Thue-Morse aperiodic optical waveguide network (PTSTMAOWN) and mainly investigate the ultrastrong extraordinary transmission and reflection. We propose an approach to study the photonic modes and solve the problem of calculating photonic modes distributions in aperiodic networks due to the lack of dispersion functions and find that in a PTSTMAOWN there exist more photonic modes and more spontaneous PT-symmetric breaking points, which are quite different from other reported PT-symmetric optical systems. Additionally, we develop a method to sort spontaneous PT-symmetric breaking point zones to seek the strongest extraordinary point and obtain that at this point the strongest extraordinary transmission and reflection arrive at 2.96316 × 10 5 and 1.32761 × 10 5 , respectively, due to the PT-symmetric coupling resonance and the special symmetry pattern of TM networks. These enormous gains are several orders of magnitude larger than the previous results. This optical system may possess potential in designing optical amplifier, optical logic elements in photon computers and ultrasensitive optical switches with ultrahigh monochromatity.

Magnetic resonance imaging of the shoulder

International Nuclear Information System (INIS)

Ilieva, E.

2015-01-01

Full text: Magnetic resonance imaging (MRI) is an excellent non-invasive imaging tool that can complement the physical examination in the evaluation of traumatic and non-traumatic injuries of the shoulder. The superb soft tissue contrast and multiplanar capabilities of MRI make it a preferred modality to provide a global assessment of the soft tissue and osseous structures of the shoulder. Learning objectives: to review briefly the anatomy of the shoulder and the specificity of sequences and planes for MRI; to demonstrate the characteristic MR findings of some of the most common shoulder disorders; to indicate how MR arthrography (MRA) of the shoulder can add extra value to the diagnostic process; to outline a systematic approach to the interpretation of the shoulder MR examination. Choosing the most suitable sequences and planes as well as the thorough knowledge of the anatomic structures assist the correct diagnosis of the pathologic disorders of the shoulder which is of great importance for the precise treatment management, surgical versus conservative, as well as for the appropriate surgical approach, open versus arthroscopic

Threshold states in /sup 26/Al. Pt. 2. Extraction of resonance strengths

Energy Technology Data Exchange (ETDEWEB)

Champagne, A E; Howard, A J; Parker, P D [Yale Univ., New Haven, CT (USA). Wright Nuclear Structure Lab.

1983-06-20

The total width of the Esub(c.m.)=376 keV resonance in the /sup 25/Mg+p system has been measured using the /sup 25/Mg(p,..gamma..)/sup 26/Al reaction and is found to be 460+-70 eV. From this information, a resonance strength ..omega gamma..=5.7x10/sup 16/ eV is obtained for the astrophysically important 37.2 keV resonance in /sup 26/Al through an R-matrix parameterization of the relative energy dependence of the resonance width. In a similar manner, an upper limit ..omega gamma..<=1.0x10/sup -11/ eV is deduced for a possible resonance at Esub(c.m.)=94.0 keV.

Electric-field tunable spin waves in PMN-PT/NiFe heterostructure: Experiment and micromagnetic simulations

Energy Technology Data Exchange (ETDEWEB)

Ziȩtek, Slawomir, E-mail: zietek@agh.edu.pl [AGH University of Science and Technology, Department of Electronics, Al. Mickiewicza 30, 30-059 Kraków (Poland); Chȩciński, Jakub [AGH University of Science and Technology, Department of Electronics, Al. Mickiewicza 30, 30-059 Kraków (Poland); AGH University of Science and Technology, Faculty of Physics and Applied Computer Science, Al. Mickiewicza 30, 30-059 Kraków (Poland); Frankowski, Marek; Skowroński, Witold; Stobiecki, Tomasz [AGH University of Science and Technology, Department of Electronics, Al. Mickiewicza 30, 30-059 Kraków (Poland)

2017-04-15

We present a comprehensive theoretical and experimental study of voltage-controlled standing spin waves resonance (SSWR) in PMN-PT/NiFe multiferroic heterostructures patterned into microstrips. A spin-diode technique was used to observe ferromagnetic resonance (FMR) mode and SSWR in NiFe strip mechanically coupled with a piezoelectric substrate. Application of an electric field to a PMN-PT creates a strain in permalloy and thus shifts the FMR and SSWR fields due to the magnetostriction effect. The experimental results are compared with micromagnetic simulations and a good agreement between them is found for dynamics of FMR and SSWR with and without electric field. Moreover, micromagnetic simulations enable us to discuss the amplitude and phase spatial distributions of FMR and SSWR modes, which are not directly observable by means of spin diode detection technique.

Hydrogen evolution from aqueous-phase photocatalytic reforming of ethylene glycol over Pt/TiO{sub 2} catalysts: Role of Pt and product distribution

Energy Technology Data Exchange (ETDEWEB)

Li, Fuying [State Key Laboratory of Photocatalysis on Energy and Environment, Research Institute of Photocatalysis, Fuzhou University, Fuzhou 350002 (China); College of Resources and Chemical Engineering, Sanming University, Sanming 365004 (China); Gu, Quan [Key Laboratory of Applied Surface and Colloid Chemistry, Ministry of Education, School of Chemistry and Chemical Engineering, Shanxi Normal University, Xi’an 710062 (China); Niu, Yu [College of Resources and Chemical Engineering, Sanming University, Sanming 365004 (China); School of Chemical Engineering, Fuzhou University, Fuzhou 350116 (China); Wang, Renzhang [College of Resources and Chemical Engineering, Sanming University, Sanming 365004 (China); Tong, Yuecong; Zhu, Shuying; Zhang, Hualei [State Key Laboratory of Photocatalysis on Energy and Environment, Research Institute of Photocatalysis, Fuzhou University, Fuzhou 350002 (China); Zhang, Zizhong, E-mail: z.zhang@fzu.edu.cn [State Key Laboratory of Photocatalysis on Energy and Environment, Research Institute of Photocatalysis, Fuzhou University, Fuzhou 350002 (China); Wang, Xuxu [State Key Laboratory of Photocatalysis on Energy and Environment, Research Institute of Photocatalysis, Fuzhou University, Fuzhou 350002 (China)

2017-01-01

Highlights: • Photocatalytic EG reforming generates many hydrocarbons besides H{sub 2}, CO{sub 2} and CO. • Pt loading greatly improves the photocatalytic activity of TiO{sub 2} for EG reforming. • Half amount of the produced H{sub 2} over Pt/TiO{sub 2} originates from EG reforming. - Abstract: Pt nanoparticles were loaded on anatase TiO{sub 2} by the photodeposition method to investigate their photocatalytic activity for H{sub 2} evolution in an aqueous solution containing a certain amount of ethylene glycol (EG) as the sacrificial agent. The surface properties and chemical states of the Pt/TiO{sub 2} sample were characterized by X-ray powder diffraction analysis, Brunauer–Emmett–Teller surface area analysis, transmission electron microscopy, X-ray photoelectron spectroscopy, electron paramagnetic resonance, and electrochemical resistance. The aqueous-phase photocatalytic EG reforming using Pt/TiO{sub 2} and anatase TiO{sub 2} generated not only H{sub 2} and CO{sub 2}, but also CO, CH{sub 4}, C{sub 2}H{sub 6}, and C{sub 2}H{sub 4}. Moreover, the amount of formate and acetate complexes in the solution increased gradually. The EG adsorption and gas-phase intermediates during photocatalytic reaction processes were investigated by the in situ FTIR spectrum. Finally, the photocatalytic EG reforming reaction mechanism was elucidated. This helped to better understand the role of a sacrificial agent in a photocatalytic hydrogen production.

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.

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

Science.gov (United States)

Cerny, Milena; Marlois, Romain; Theumann, Nicolas; Bollmann, Christof; Wehrli, Laurent; Richarme, Delphine; Meuli, Reto; Becce, Fabio

2013-10-01

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. 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. With finger trap distraction, both readers found a significant increase in width of the SL space (mean Δ = +0.1mm, 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 = 0mm, 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). 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. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

Proceedings of the nuclear magnetic resonance user meeting

International Nuclear Information System (INIS)

1987-01-01

Studies on utilization of nuclear magnetic resonance, such as: chemical analysis in complexes and organic compounds; structures and magnetic properties of solids; construction of images and; spectrometer designs, are presented. (M.C.K.) [pt

Reversibility of Pt-Skin and Pt-Skeleton Nanostructures in Acidic Media.

Science.gov (United States)

Durst, Julien; Lopez-Haro, Miguel; Dubau, Laetitia; Chatenet, Marian; Soldo-Olivier, Yvonne; Guétaz, Laure; Bayle-Guillemaud, Pascale; Maillard, Frédéric

2014-02-06

Following a well-defined series of acid and heat treatments on a benchmark Pt3Co/C sample, three different nanostructures of interest for the electrocatalysis of the oxygen reduction reaction were tailored. These nanostructures could be sorted into the "Pt-skin" structure, made of one pure Pt overlayer, and the "Pt-skeleton" structure, made of 2-3 Pt overlayers surrounding the Pt-Co alloy core. Using a unique combination of high-resolution aberration-corrected STEM-EELS, XRD, EXAFS, and XANES measurements, we provide atomically resolved pictures of these different nanostructures, including measurement of the Pt-shell thickness forming in acidic media and the resulting changes of the bulk and core chemical composition. It is shown that the Pt-skin is reverted toward the Pt-skeleton upon contact with acid electrolyte. This change in structure causes strong variations of the chemical composition.

Coulomb excitation of the 4+1 states of 194Pt, 196Pt and 198Pt

International Nuclear Information System (INIS)

Fewell, M.P.; Gyapong, G.J.; Spear, R.H.

1987-09-01

Probabilities for the Coulomb excitation of the 4 1 + states of 194 Pt, 196 Pt, 198 Pt by the backscattering of 4 He, 12 C and 16 O ions are reported. Model-independent values of the matrix elements 1 + ; M(E4), 4 1 + > and 1 + , M(E2), 4 1 + > are extracted. Agreement with previous measurements of these matrix elements is good. Values of β 2 and β 4 are determined for 194 Pt and compared with calculations of these quantities

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

International Nuclear Information System (INIS)

Schmaranzer, Florian; Klauser, Andrea; Henninger, Benjamin; Kogler, Michael; Schmaranzer, Ehrenfried; Forstner, Thomas; Reichkendler, Markus

2015-01-01

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.)

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.)

MR imaging of the shoulder

International Nuclear Information System (INIS)

Fritts, H.M.; Craig, E.; Kyle, R.; Strefling, M.; Miller, D.; Heithoff, K.; Schellhas, K.

1988-01-01

Magnetic resonance (MR) imaging (1.5-T unit) was performed in over 600 shoulders to evaluate shoulder pain. Ultrasound (US) and arthrography were performed in over 100 patients. Surgery was performed in over 75 patients. MR imaging offers information not well evaluated with other modalities, including bony impingement, tendinitis, bursitis, and osseous abnormalities, such as primary arthritis, avascular necrosis, occult fractures, and tumors. US and MR findings correlate well with surgical findings for medium to large rotator cuff tears. MR imaging with T2 weighting is superior for differentiating small tears from associated tendinitis. An algorithm for cost-effective shoulder imaging integrating US, MR imaging, arthrography, and computed tomographic arthrography are presented

Ulnar-sided wrist pain. II. Clinical imaging and treatment

Energy Technology Data Exchange (ETDEWEB)

Watanabe, Atsuya; Souza, Felipe [Brigham and Women' s Hospital, Department of Radiology, Boston, MA (United States); Vezeridis, Peter S.; Blazar, Philip [Brigham and Women' s Hospital, Department of Orthopaedic Surgery, Boston, MA (United States); Yoshioka, Hiroshi [Brigham and Women' s Hospital, Department of Radiology, Boston, MA (United States); University of California-Irvine, Department of Radiological Sciences, Irvine, CA (United States); UC Irvine Medical Center, Department of Radiological Sciences, Orange, CA (United States)

2010-09-15

Pain at the ulnar aspect of the wrist is a diagnostic challenge for hand surgeons and radiologists due to the small and complex anatomical structures involved. In this article, imaging modalities including radiography, arthrography, ultrasound (US), computed tomography (CT), CT arthrography, magnetic resonance (MR) imaging, and MR arthrography are compared with regard to differential diagnosis. Clinical imaging findings are reviewed for a more comprehensive understanding of this disorder. Treatments for the common diseases that cause the ulnar-sided wrist pain including extensor carpi ulnaris (ECU) tendonitis, flexor carpi ulnaris (FCU) tendonitis, pisotriquetral arthritis, triangular fibrocartilage complex (TFCC) lesions, ulnar impaction, lunotriquetral (LT) instability, and distal radioulnar joint (DRUJ) instability are reviewed. (orig.)

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.

The 130Te (p,p') reaction on analog resonances

International Nuclear Information System (INIS)

Martinez Ruiz, M. del C.H.; Cescato, M.L.; Foster Junior, J.L.; Krmpotic, F.

1983-07-01

Angular distributions for elastic and inelastic scattering have been measured on six analog resonances in the 130 Te + p system and at two off resonance energies. Partial widths are deduced from the angular distributions. Formulae for the spectroscopic amplitudes within the framework of quasiparticle random phase approximation are presented. The experimental results are compared with the theoretical predictions. (Author) [pt

Accuracy of magnetic resonance studies in the detection of chondral and labral lesions in femoroacetabular impingement: systematic review and meta-analysis.

Science.gov (United States)

Saied, A M; Redant, C; El-Batouty, M; El-Lakkany, M R; El-Adl, W A; Anthonissen, J; Verdonk, R; Audenaert, E A

2017-02-16

Several types of Magnetic resonance imaging (MRI) are commonly used in imaging of femoroacetabular impingement (FAI), however till now there are no clear protocols and recommendations for each type. The aim of this meta-analysis is to detect the accuracy of conventional magnetic resonance imaging (cMRI), direct magnetic resonance arthrography (dMRA) and indirect magnetic resonance arthrography (iMRA) in the diagnosis of chondral and labral lesions in femoroacetabular impingement (FAI). A literature search was finalized on the 17th of May 2016 to collect all studies identifying the accuracy of cMRI, dMRA and iMRA in diagnosing chondral and labral lesions associated with FAI using surgical results (arthroscopic or open) as a reference test. Pooled sensitivity and specificity with 95% confidence intervals using a random-effects meta-analysis for MRI, dMRA and iMRA were calculated also area under receiver operating characteristic (ROC) curve (AUC) was retrieved whenever possible where AUC is equivocal to diagnostic accuracy. The search yielded 192 publications which were reviewed according inclusion and exclusion criteria then 21 studies fulfilled the eligibility criteria for the qualitative analysis with a total number of 828 cases, lastly 12 studies were included in the quantitative meta-analysis. Meta-analysis showed that as regard labral lesions the pooled sensitivity, specificity and AUC for cMRI were 0.864, 0.833 and 0.88 and for dMRA were 0.91, 0.58 and 0.92. While in chondral lesions the pooled sensitivity, specificity and AUC for cMRI were 0.76, 0.72 and 0.75 and for dMRA were 0.75, 0.79 and 0.83, while for iMRA were sensitivity of 0.722 and specificity of 0.917. The present meta-analysis showed that the diagnostic test accuracy was superior for dMRA when compared with cMRI for detection of labral and chondral lesions. The diagnostic test accuracy was superior for labral lesions when compared with chondral lesions in both cMRI and dMRA. Promising results are

Resonance production in central pp collisions at the CERN Omega Spectrometer

CERN Document Server

Kirk, A.

2000-01-01

A study of resonance production in central pp collisions is presented as a function of several kinematical variables. In particular the difference in the transverse momentum (dPT) of the exchanged particles shows that undisputed qqbar mesons are suppressed at small dPT whereas glueball candidates are enhanced and in addition, the azimuthal angle phi gives information on the nature of the Pomeron.

Magnetic islands created by resonant helical windings

International Nuclear Information System (INIS)

Fernandes, A.S.; Heller, M.V.; Caldas, I.L.

1986-01-01

The triggering of disruptive instabilities by resonant helical windings in large aspect-ratio tokamaks is associated to destruction of magnetic surfaces. The Chirikov condition is applied to estimate analytically the helical winding current thresholds for ergodization of the magnetic field lines. (Autor) [pt

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. ....... The tests were sent from the EURL in the beginning of September 2012. Both PT1 and PT2 are accredited by DANAK under registration number 515 for proficiency testing according to the quality assurance standard DS/EN ISO/IEC 17043....

Magnetic properties and configuration of Fe{sub 50}Pt{sub 50*x}Rh{sub x} films

Energy Technology Data Exchange (ETDEWEB)

Fenske, Jochen; Lott, Dieter; Schreyer, Andreas [Helmholt-Zentrum, Geesthacht (Germany); Schmidt, Wolfgang; Schmalzl, Karin [IFF Forschungszentrum, Juelich (Germany); JCNS at ILL (France); Mankey, Gary J. [MINT Center, University of Alabama (United States); Klose, Frank [Ansto, Bragg Institute (Australia); Tartakowskaya, Helena [Institute for Magnetism, National Accademy of Scinece (Ukraine)

2011-07-01

Ordered FePt alloys with L1{sub 0} structure are known as materials with FM order and a high magnetic moment of Fe providing a large magnetization. The large atomic number of Pt on the other hand results in a high magnetic anisotropy. If grown in thin films, the high anisotropy often results in perpendicular magnetization which is the preferred orientation for current magnetic recording media. One way to control the magnetic properties in these materials is through the introduction of a third element into the crystal matrix e.g. Rh. When Rh is added to replace Pt in the equiatomic alloy, new magnetic phases emerge. Here we present neutron diffraction studies on the magnetic properties of different 200nm thick Fe{sub 50}Pt{sub 50*x}Rh{sub x} films in dependence of the temperature and external magnetic fields. Additional resonant x-ray measurements on the Fe and Pt absorption edges provide additional information about the magnetic moments on these sites.

Mesoporous Pt and Pt/Ru alloy electrocatalysts for methanol oxidation

Energy Technology Data Exchange (ETDEWEB)

Franceschini, Esteban A. [Grupo de Celdas de Combustible, Departamento de Fisica de la Materia Condensada, Centro Atomico Constituyentes, CNEA. Av. General Paz 1499 (1650), San Martin, Buenos Aires (Argentina); Planes, Gabriel A. [Departamento de Quimica, Facultad de Ciencias Exactas, Fisicoquimicas y Naturales, Universidad Nacional de Rio Cuarto, Agencia Postal No 3, 5800, Rio Cuarto (Argentina); Williams, Federico J. [Departamento de Quimica Inorganica, Analitica y Quimica-Fisica, INQUIMAE CONICET, Facultad Ciencias Exactas y Naturales, Pabellon 2, Ciudad Universitaria, Buenos Aires (Argentina); Soler-Illia, Galo J.A.A. [Gerencia de Quimica, Centro Atomico Constituyentes, CNEA. Av. General Paz 1499 (1650), San Martin, Buenos Aires (Argentina); Corti, Horacio R. [Grupo de Celdas de Combustible, Departamento de Fisica de la Materia Condensada, Centro Atomico Constituyentes, CNEA. Av. General Paz 1499 (1650), San Martin, Buenos Aires (Argentina); Departamento de Quimica Inorganica, Analitica y Quimica-Fisica, INQUIMAE CONICET, Facultad Ciencias Exactas y Naturales, Pabellon 2, Ciudad Universitaria, Buenos Aires (Argentina)

2011-02-15

Mesoporous Pt and Pt/Ru catalysts with 2D-hexagonal mesostructure were synthesized using a triblock poly(ethylene oxide)-b-poly(propylene oxide)-b-poly(ethylene oxide) copolymer (Pluronic F127 {sup registered}) template, on a gold support. Large electrochemical surface areas were observed for the catalysts prepared at high overpotentials. Compared to the Pt catalyst, the Pt/Ru alloy containing 3 at% of Ru exhibited lower onset potential and more than three times the limit mass activity for methanol oxidation. This behavior is assigned to the larger pore size of the mesoporous Pt and Pt/Ru catalysts obtained with this template that seems to improve the methanol accessibility to the active sites compared to those obtained using lyotropic liquid crystals. (author)

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.)

Evaluation of the Subscapularis Tendon Tears on 3T Magnetic Resonance Arthrography: Comparison of Diagnostic Performance of T1-Weighted Spectral Presaturation with Inversion-Recovery and T2-Weighted Turbo Spin-Echo Sequences.

Science.gov (United States)

Lee, Hoseok; Ahn, Joong Mo; Kang, Yusuhn; Oh, Joo Han; Lee, Eugene; Lee, Joon Woo; Kang, Heung Sik

2018-01-01

To compare the T1-weighted spectral presaturation with inversion-recovery sequences (T1 SPIR) with T2-weighted turbo spin-echo sequences (T2 TSE) on 3T magnetic resonance arthrography (MRA) in the evaluation of the subscapularis (SSC) tendon tear with arthroscopic findings as the reference standard. This retrospective study included 120 consecutive patients who had undergone MRA within 3 months between April and December 2015. Two musculoskeletal radiologists blinded to the arthroscopic results evaluated T1 SPIR and T2 TSE images in separate sessions for the integrity of the SSC tendon, examining normal/articular-surface partial-thickness tear (PTTa)/full-thickness tear (FTT). Diagnostic performance of T1 SPIR and T2 TSE was calculated with arthroscopic results as the reference standard, and sensitivity, specificity, and accuracy were compared using the McNemar test. Interobserver agreement was measured with kappa (κ) statistics. There were 74 SSC tendon tears (36 PTTa and 38 FTT) confirmed by arthroscopy. Significant differences were found in the sensitivity and accuracy between T1 SPIR and T2 TSE using the McNemar test, with respective rates of 95.9-94.6% vs. 71.6-75.7% and 90.8-91.7% vs. 79.2-83.3% for detecting tear; 55.3% vs. 31.6-34.2% and 85.8% vs. 78.3-79.2%, respectively, for FTT; and 91.7-97.2% vs. 58.3-61.1% and 89% vs. 78-79.3%, respectively, for PTTa. Interobserver agreement for T1 SPIR was almost perfect for T1 SPIR (κ = 0.839) and substantial for T2 TSE (κ = 0.769). T1-weighted spectral presaturation with inversion-recovery sequences is more sensitive and accurate compared to T2 TSE in detecting SSC tendon tear on 3T MRA.

Anomalous Fluctuations of s-Wave Reduced Neutron Widths of 192,194Pt Resonances

International Nuclear Information System (INIS)

Koehler, P. E.; Harvey, J. A.; Becvar, F.; Krticka, M.; Guber, K. H.

2010-01-01

We obtained an unprecedentedly large number of s-wave neutron widths through R-matrix analysis of neutron cross-section measurements on enriched Pt samples. Careful analysis of these data rejects the validity of the Porter-Thomas distribution with a statistical significance of at least 99.997%.

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.

Giant resonances: reaction theory approach

International Nuclear Information System (INIS)

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

1989-09-01

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

Ethanol electrooxidation on Pt-Sn and Pt-Sn-W bulk alloys

Energy Technology Data Exchange (ETDEWEB)

Anjos, D.M. dos; Hahn, F.; Leger, J.M.; Kokoh, K.B. [Universite de Poitiers, Poitiers Cedex (France). Centre National de la Recherche Scientifique (CNRS). Equipe Electrocatalyse; Tremiliosi-Filho, G. [Universidade de Sao Paulo (USP), Sao Carlos, SP (Brazil). Inst. de Quimica

2008-07-01

Ethanol oxidation has been studied on Pt-Sn and Pt-Sn-W electrodes prepared in an arc-melting furnace. Different electrochemical techniques like cyclic voltammetry and chronoamperometry were used to evaluate the catalytic activity of these materials. The electro-oxidation process was also investigated by in situ infrared reflectance spectroscopy in order to determine adsorbed intermediates and reaction products. Experimental results indicated that Pt-Sn and Pt-Sn-W alloys are able to oxidize ethanol mainly to acetaldehyde and acetic acid. Adsorbed CO was also detected, demonstrating the viability of splitting the C-C bond in the ethanol molecule during the oxidation process. The adsorbed CO was further oxidized to CO{sub 2}.This reaction product was clearly detected by SNIFTIRS. Pt-Sn-W catalyst showed a better electrochemical performance than Pt-Sn that, in it turn, is better than Pt-alone. (author)

Pt/MOx/SiO2, Pt/MOx/TiO2, and Pt/MOx/Al2O3 Catalysts for CO Oxidation

Directory of Open Access Journals (Sweden)

Hongmei Qin

2015-04-01

Full Text Available Conventional supported Pt catalysts have often been prepared by loading Pt onto commercial supports, such as SiO2, TiO2, Al2O3, and carbon. These catalysts usually have simple metal-support (i.e., Pt-SiO2 interfaces. To tune the catalytic performance of supported Pt catalysts, it is desirable to modify the metal-support interfaces by incorporating an oxide additive into the catalyst formula. Here we prepared three series of metal oxide-modified Pt catalysts (i.e., Pt/MOx/SiO2, Pt/MOx/TiO2, and Pt/MOx/Al2O3, where M = Al, Fe, Co, Cu, Zn, Ba, La for CO oxidation. Among them, Pt/CoOx/SiO2, Pt/CoOx/TiO2, and Pt/CoOx/Al2O3 showed the highest catalytic activities. Relevant samples were characterized by N2 adsorption-desorption, X-ray diffraction (XRD, transmission electron microscopy (TEM, H2 temperature-programmed reduction (H2-TPR, X-ray photoelectron spectroscopy (XPS, CO temperature-programmed desorption (CO-TPD, O2 temperature-programmed desorption (O2-TPD, and CO2 temperature-programmed desorption (CO2-TPD.

Exchange coupled CoPt/FePtC media for heat assisted magnetic recording

Science.gov (United States)

Dutta, Tanmay; Piramanayagam, S. N.; Ru, Tan Hui; Saifullah, M. S. M.; Bhatia, C. S.; Yang, Hyunsoo

2018-04-01

L10 FePtC granular media are being studied as potential future magnetic recording media and are set to be used in conjunction with heat assisted magnetic recording (HAMR) to enable recording at write fields within the range of current day recording heads. Media structures based on a FePtC storage layer and a capping layer can alleviate the switching field distribution (SFD) requirements of HAMR and reduce the noise originating from the writing process. However, the current designs suffer from SFD issues due to high temperature writing. To overcome this problem, we study a CoPt/FePtC exchange coupled composite structure, where FePtC serves as the storage layer and CoPt (with higher Curie temperature, Tc) as the capping layer. CoPt remains ferromagnetic at near Tc of FePtC. Consequently, the counter exchange energy from CoPt would reduce the noise resulting from the adjacent grain interactions during the writing process. CoPt/FePtC bilayer samples with different thicknesses of CoPt were investigated. Our studies found that CoPt forms a continuous layer at a thickness of 6 nm and leads to considerable reduction in the saturation field and its distribution.

Spin-orbit torque opposing the Oersted torque in ultrathin Co/Pt bilayers

Energy Technology Data Exchange (ETDEWEB)

Skinner, T. D., E-mail: tds32@cam.ac.uk; Irvine, A. C.; Heiss, D.; Kurebayashi, H.; Ferguson, A. J., E-mail: ajf1006@cam.ac.uk [Cavendish Laboratory, University of Cambridge, Cambridge CB3 0HE (United Kingdom); Wang, M.; Hindmarch, A. T.; Rushforth, A. W. [School of Physics and Astronomy, University of Nottingham, Nottingham NG7 2RD (United Kingdom)

2014-02-10

Current-induced torques in ultrathin Co/Pt bilayers were investigated using an electrically driven ferromagnetic resonance technique. The angle dependence of the resonances, detected by a rectification effect as a voltage, was analysed to determine the symmetries and relative magnitudes of the spin-orbit torques. Both anti-damping (Slonczewski) and field-like torques were observed. As the ferromagnet thickness was reduced from 3 to 1 nm, the sign of the sum of the field-like torque and Oersted torque reversed. This observation is consistent with the emergence of a Rashba spin orbit torque in ultra-thin bilayers.

New methodology for analytical calculation of resonance integrals in an heterogeneous medium

International Nuclear Information System (INIS)

Campos, T.P.R. de; Martinez, A.S.

1986-01-01

A new methodology for analytical calculation of Resonance Integral in a typical fuel cell is presented. The expression obtained for the Resonance Integral presents the advantage of being analytical. Its constituent terms are combinations of the well known function J(xi,β) with its partial derivatives in regard to β. This is a general expression for all types of resonance. The parameters used in this method depend on the resonance type and are obtained as a function of the parameter lambda. A simple expression, depending on resonance parameters is proposed for this variable. (Author) [pt

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.)

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

International Nuclear Information System (INIS)

Jung, Joon-Yong; Jee, Won-Hee; Park, Michael Y.; Lee, So-Yeon; Kim, Yang-Soo

2012-01-01

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 (κ) 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.)

The analog resonance of 208Pb

International Nuclear Information System (INIS)

Brinati, J.R.; Bund, G.W.

1973-01-01

Elastic and inelastic partial proton widths and Coulomb displacement energies for the IAR of the Ground State of 208 Pb are calculated in the Blair-Bund model. Exchange terms are included and different optical potentials are considered. Comparison with the experimental widths is made taking into account the off-resonance cross sections predicted by the optical potentials [pt

Interior and exterior resonances in acoustic scattering. pt. 1 - spherical targets

International Nuclear Information System (INIS)

Gaunaurd, G.C.; Tanglis, E.; Uberall, H.; Brill, D.

1983-01-01

In acoustic scattering from elastic objects, resonance features appear in the returned echo at frequencies at which the object's eigenfrequencies are located, which are explained by the excitation of 'interior' creeping waves. Corresponding resonance terms may be split off from the total scattering amplitude, leaving behind an apparently nonresonant background amplitude. This is demonstrated here for scatterers of spherical geometry and in a companion paper also for scatterers of arbitrary geometry, by using the T-matrix approach. For the case of near-impenetrable spheres, it is subsequently shown that the background amplitude can be split further into specularly reflected contributions, plus highly attenuated resonance terms which are explained by the excitation of 'exterior' (Franz-type) creeping waves. The singularity structure of the scattering function is shown mathematically, by using the R-matrix approach of the nuclear-scattering theory, as that of a meromorphic function 'without' any additional 'entire function' (as had been postulated by the singularity expansion method)

Pt Skin Versus Pt Skeleton Structures of Pt₃Sc as Electrocatalysts for Oxygen Reduction

DEFF Research Database (Denmark)

Johansson, Tobias Peter; Ulrikkeholm, Elisabeth Therese; Hernandez-Fernandez, Patricia

2014-01-01

. The development of new materials for this reaction is essential in order to increase the overall effeciency of the fuel cell. Herein, we study the effect of ultra high vacuum annealing on the structure and activity of polycrystalline Pt3Sc. Upon annealing in ultra high vacuum a Pt overlayer is formed......, relative to Pt(111), consistent with the CO adsorption energies calculated using density functional theory calculations. Exposing the annealed Pt3Sc sample to 200 mbar O2 at room temperature results in similar to 14 % Sc oxide as measured by X-ray photoelectron spectroscopy. Electrochemical testing...

Carbon supported nanoparticles Pt Ru (Pt Ru/C electrocatalysts) prepared using electron beam irradiation; Preparacao de nanoparticulas de PtRu suportadas em carbono (eletrocatalisadores PtRu/C) utilizando feixe de eletrons

Energy Technology Data Exchange (ETDEWEB)

Silva, Dionisio F. da; Oliveira Neto, Almir; Pino, Eddy S.; Linardi, Marcelo; Spinace, Estevam V. [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil). Programa de Celulas a Combustivel], e-mail: espinace@ipen.br, e-mail: dfsilva@ipen.br

2006-07-01

Carbon-supported Pt Ru (electrocatalysts PtRu/C nanoparticles) were prepared submitting a water/ethylene glycol mixture containing Pt(IV) and Ru(III) ions and the carbon support to electron beam irradiation. The PtRu/C electrocatalysts were characterized by EDX, XRD and cyclic voltammetry and tested for methanol electro-oxidation aiming fuel cell application. The obtained PtRu/C electrocatalysts were more active for methanol electro-oxidation than the commercial PtRu/C ETEK electrocatalyst at ambient temperature. (author)

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.

Dating by electron paramagnetic resonance

International Nuclear Information System (INIS)

Poupeau, G.; Rossi, A.M.

1984-01-01

Some natural materials behave like dosimeters in front of the ionizing particle flux coming from environmental radioactivity and the cosmic radiation. This property is used for the dating by Electron Paramagnetic Resonance (EPR). Before presenting the basic principles of the EPR analysis and the dating method which uses such a phenomenous, it is reviewed several types of application currently in course of development. (L.C.) [pt

An analysis of stripping to isolated analog resonances

International Nuclear Information System (INIS)

Pessoa, E.F.; Toledo Piza, A.F.R. de.

1983-04-01

The Feshbach projection formalism is used to calculate the form factors for the (d,n) stripping process to isolated analog resonances. These are used in a standard DWBA stripping calculation in which the radial integration over all space is accomplished by including outerspace contributions evaluated along the complex contours of Vincent and Fortune. It turns out that the shape and magnitude of the predicted cross section is quite insensitive to the continuum proton wave emanating from the resonant residual state. (Author) [pt

Reduction of Pt{sup 2+} species in model Pt–CeO{sub 2} fuel cell catalysts upon reaction with methanol

Energy Technology Data Exchange (ETDEWEB)

Neitzel, Armin [Lehrstuhl für Physikalische Chemie II, Friedrich-Alexander-Universität Erlangen-Nürnberg, Egerlandstrasse 3, 91058 Erlangen (Germany); Johánek, Viktor [Charles University, Faculty of Mathematics and Physics, Department of Surface and Plasma Science, V Holešovičkách 2, 18000 Prague (Czech Republic); Lykhach, Yaroslava, E-mail: yaroslava.lykhach@fau.de [Lehrstuhl für Physikalische Chemie II, Friedrich-Alexander-Universität Erlangen-Nürnberg, Egerlandstrasse 3, 91058 Erlangen (Germany); Skála, Tomáš; Tsud, Nataliya; Vorokhta, Mykhailo; Matolín, Vladimír [Charles University, Faculty of Mathematics and Physics, Department of Surface and Plasma Science, V Holešovičkách 2, 18000 Prague (Czech Republic); Libuda, Jörg [Lehrstuhl für Physikalische Chemie II, Friedrich-Alexander-Universität Erlangen-Nürnberg, Egerlandstrasse 3, 91058 Erlangen (Germany); Erlangen Catalysis Resource Center, Friedrich-Alexander-Universität Erlangen-Nürnberg, Egerlandstrasse 3, 91058 Erlangen (Germany)

2016-11-30

Highlights: • Pt{sup 2+} species are reduced upon reaction with methanol. • Reduction of one Pt{sup 2+} requires presence of two oxygen vacancies. • Reduction of Pt{sup 2+} species leads to formation of ultra-small Pt particles. • Ultra-small Pt particles (around 25 atoms or less) are resistant to sintering. - Abstract: The stability of atomically dispersed Pt{sup 2+} species on the surface of nanostructured CeO{sub 2} films during the reaction with methanol has been investigated by means of synchrotron radiation photoelectron spectroscopy and resonant photoemission spectroscopy. The isolated Pt{sup 2+} species were prepared at low Pt concentration in Pt–CeO{sub 2} film. Additionally, Pt{sup 2+} 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–CeO{sub 2} films. A small number of oxygen vacancies formed during the methanol decomposition can be replenished in the Pt–CeO{sub 2} 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 Pt{sup 2+} species. The isolated Pt{sup 2+} species are reduced under rather strongly reducing conditions only, i.e. during annealing under continuous exposure to methanol. Reduction of isolated Pt{sup 2+} 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–CeO{sub 2} film with low Pt concentration under reducing conditions.

Radiological examinations of complications after total hip replacement Pt. 1

International Nuclear Information System (INIS)

Luzsa, Gyoergy; Reti, Peter; Lakatos, Jozsef

1985-01-01

The radiological findings of complications after total hip replacement are summarized by analizing the data of control examinations of the operated patients at the National Institute for Rheumatology and Physiotherapy. In this first part the types of total hip replacements and the radiological methods (native x-ray, fistulography, arthrography, needle biopsy and scintigraphy using sup(99m)Tc isotope) are surveyed, and the radiological findings of the septic surgical complications are described. (author)

The Nuclear Magnetic Resonance and its utilization in image formation

International Nuclear Information System (INIS)

Bonagamba, T.J.; Tannus, A.; Panepucci, H.

1987-01-01

Some aspects about Nuclear Magnetic Resonance (as Larmor Theorem, radio frequency pulse, relaxation of spins system) and its utilization in two dimensional image processing with the necessity of a tomography plane are studied. (C.G.C.) [pt

Coherent and incoherent processes in resonant photoemission

Energy Technology Data Exchange (ETDEWEB)

Magnuson, M.; Karis, O.; Weinelt, M. [Uppsala Univ. (Sweden)] [and others

1997-04-01

In this contribution the authors present the distinction between coherent and incoherent processes in resonant photoemission. As a first step they determine whether an autoionization process is photoemission-like or Auger-like. The discussion is based on measurements for a weakly bonded adsorption system, Ar/Pt(111). This type of system is well adapted to investigate these effects since it yields distinctly shifted spectral features depending on the nature of the process. After this, the question of resonance photoemission in metallic systems is addressed. This is done in connection with measurements at the 2p edges for Ni metal. Ni has been one of the prototype systems for resonant photoemission. The resonances have been discussed in connection with the strong correlation and d-band localization effects in this system. Based on the results some general comments about the appearance of resonant effects in metallic systems are made.

Sonochemical synthesis and characterization of Pt/CNT, Pt/TiO2, and Pt/CNT/TiO2 electrocatalysts for methanol electro-oxidation

International Nuclear Information System (INIS)

Bedolla-Valdez, Z.I.; Verde-Gómez, Y.; Valenzuela-Muñiz, A.M.; Gochi-Ponce, Y.; Oropeza-Guzmán, M.T.; Berhault, Gilles; Alonso-Núñez, G.

2015-01-01

Highlights: • Pt/CNT/TiO 2 electrocatalyst was successfully prepared by the sonochemical method. • The electrocatalyst Pt/CNT/TiO 2 was synthesized without heat treatments, additives or surfactants. • The TiO 2 -Pt interaction improves the CO-tolerance of Pt/CNT/TiO 2 , as well as the electrocatalyst stability. • Low amount of multi-walled carbon nanotubes increases the current density of Pt/CNT/TiO 2 significantly compared to Pt/TiO 2 . - Abstract: Pt electrocatalyst supported on composite formed of multi-walled carbon nanotubes and titanium oxide (CNT/TiO 2 ) was successfully synthesized by a sonochemical method without heat treatments, surfactants or additives. This electrocatalyst could be used for direct methanol fuel cells (DMFC) applications. For comparison, Pt/CNT and Pt/TiO 2 electrocatalysts were prepared as reference samples. Structural properties and morphology of the synthesized materials were examined by X-ray diffraction, transmission electron microscopy, Raman spectroscopy, X-ray photoelectron spectroscopy and their specific surface areas were determined by the Brunauer-Emmett-Teller method. The Pt and acid-treated CNT contents were analyzed by inductively coupled plasma atomic emission spectroscopy and thermogravimetric analysis, respectively. The electrochemical properties of the synthesized electrocatalysts were evaluated by cyclic voltammetry (CV) and chronoamperometry in a three-electrode cell at room temperature. The evaluation performed using electrochemical techniques suggests that TiO 2 promotes the CO-tolerance due to TiO 2 -Pt interaction. The CV tests demonstrated that 6 wt.% of acid-treated CNT increases significantly the current density when Pt selectively interacts with TiO 2 .

Pengukuran Kepuasan Kerja Karyawan APLP & A PT Semen Padang (PT X

Directory of Open Access Journals (Sweden)

Shelly Nolandari

2016-04-01

Full Text Available Thoughts on employee satisfaction arise because the company believes its employees have a high level of satisfaction will result in a better level of productivity, work more accurate, the fewer the number of absences and higher loyalty than employees with low satisfaction levels.Company's with good productivity will grow and increase revenue. PT Semen Padang has several subsidiaries and affiliates like PT X. PT X will measure employee satisfaction with the company's expectations are always making changes that sustainable about employee satisfaction because companies believe that employee satisfaction level of its high yield levels better productivity, work more accurate, the number of absences are fewer and loyalty higher than employees with low satisfaction levels. Companies with good productivity will experience growth as indicated by the increase in revenue, in line with the increase in the welfare of the employees. PT Semen Padang has several subsidiaries and affiliates PT X. PT Xwill measure employee satisfaction with the Company's expectations.

Damping constant of Co/Pt multilayer thin-film media

International Nuclear Information System (INIS)

Fujita, N.; Inaba, N.; Kirino, F.; Igarashi, S.; Koike, K.; Kato, H.

2008-01-01

Gilbert's damping constants, α, of Co(t Co )/Pt (1.4 nm) multilayer thin films are investigated by Q-band FMR analysis. α is calculated from the resonance width of the FMR spectrum. With decreasing t Co , the α value decreases from 0.034 (t Co =8.7 nm) to 0.023 (t Co =1.8 nm), and then increases to 0.037 (t Co =1.0 nm). The decrease of α with t Co >1.8 nm is probably due to the eddy current loss effects. The increase of α with t Co <1.8 nm would be caused by the increase of the distortion between the Co and the Pt layers at the interface. When the magnetic field direction was changed from θ=90 deg. (parallel to the specimen) to θ=0 deg. (perpendicular to the specimen), the α of all the specimens increased, and a sharp step in α was observed around θ=40 deg., where the α has the maximum value

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

International Nuclear Information System (INIS)

Gerscovich, E.O.

1997-01-01

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

Direct vs statistical decay of nuclear giant multipole resonances

International Nuclear Information System (INIS)

Dias, H.; Hussein, M.S.; Carlson, B.V.; Merchant, A.C.; Adhikari, S.K.

1986-01-01

A theoretical framework for the description of the decay of giant multipole resonances id developed. Besides the direct decay, both the pre-equilibrium and statistical (compound) decays are taken into account in a consistent way. It is shown that the statistical decay of the giant resonance is not necessarily described by the Hauser-Feshbach theory owing to the presence of a mixing parameter, which measures the degree of fragmentation. Applications are made to several cases. (Author) [pt

Construction of Au@Pt core—satellite nanoparticles based on in-situ reduction of polymeric ionic liquid protected gold nanoparticles

Science.gov (United States)

Wu, Wenlan; Li, Junbo; Zou, Sheng; Guo, Jinwu; Zhou, Huiyun

2017-03-01

A method of in-situ reduction to prepare Au@Pt core-satellite nanoparticles (NPs) is described by using Au NPs coating poly[1-methyl 3-(2-methacryloyloxy propylimidazolium bromine)] (PMMPImB-@-Au NPs) as the template. After electrostatic complex chloroplatinic acid with PMMPImB shell, the composite NP was directly reduced with N2H4 to produce Au@Pt core-satellite NPs. The characterization of composite and core-satellite NPs under different amounts of chloroplatinic acid were studied by DLS, UV-vis absorption spectrum and TEM. The satellite Pt NPs with a small size ( 2 nm) dotted around Au core, and the resulting Au@Pt core-satellite NPs showed a red-shift surface plasmon resonance (SPR) and a good dispersion due to effectively electrostatic repulsion providing by the polymeric ionic liquid (PIL) shell. Finally, Au@Pt core-satellite NPs exhibit an enhanced catalytic activity and cycled catalytic capability for the reduction of p-nitrophenol with NaBH4.

Pt, PtCo and PtNi electrocatalysts prepared with mechanical alloying for oxygen reduction reaction in alkaline medium; Electrocatalizadores de Pt, PtCo y PtNi preparados por aleado mecanico para la reaccion de reduccion de oxigeno en medio alcalino

Energy Technology Data Exchange (ETDEWEB)

Garcia-Contreras, M.A.; Fernandez-Valverde, S.M. [Instituto Nacional de Investigaciones Nucleares, Ocoyoacac, Estado de Mexico (Mexico)]. E-mail: miguel.garcia@inin.gob.mx; Vargas-Garcia, J.R. [ESIQIE-IPN, Mexico D.F. (Mexico

2009-09-15

Pt, PtCo and PtNi electrocatalysts were prepared using mechanical alloying and their electrocatalytic activity was investigated for oxygen reduction reaction (ORR) in KOH 0.5 M using cyclic voltametry and rotary disc electrode (RDE) techniques. The electrocatalysts were characterized using x-ray diffraction, sweep electron microscopy, dispersive x-ray transmission and chemical analysis. The physical characterization indicated that all the electrocatalysts are alloys formed by agglomerated particles composed of nanocrystals. The chemical analysis showed the presence of iron in the alloys. For the electrocatalytic evaluation, polarization curves and Koutecky-Levich and Tafel graphs were obtained to determine the kinetic parameters of the electrocatalysts in the study. With the same experimental conditions, the PtCo presented better electrocatalytic performance with a higher exchange current density. [Spanish] Se prepararon electrocatalizadores de Pt, PtCo y PtNi por aleado mecanico y se investigo su actividad electrocatalitica para la reaccion de reduccion de oxigeno (RRO) en KOH 0.5 M utilizando las tecnicas de Voltametria ciclica y Electrodo de Disco Rotatorio. Los electrocatalizadores se caracterizaron por difraccion de rayos X, Microscopia electronica de Barrido, de Transmision y analisis quimico por dispersion de rayos X. La caracterizacion fisica indico que todos los electrocatalizadores son aleaciones formadas de particulas aglomeradas, compuestas de nanocristales. El analisis quimico mostro la presencia de hierro en las aleaciones. Para la evaluacion electrocatalitica se obtuvieron curvas de polarizacion, graficas de Koutecky-Levich y de Tafel para determinar los parametros cineticos de los electrocatalizadores en estudio. En las mismas condiciones experimentales, el PtCo presento el mejor desempeno electrocatalitico con la densidad de corriente de intercambio mas alta.

Method to obtain resonances and virtual states

International Nuclear Information System (INIS)

Adhikari, S.K.; Fonseca, A.C.; Tomio, L.

1982-01-01

A naive method is proposed for the calculation of resonance position and-residue at low energies and of virtual states localized in the non-physical sheet associated to the lowest threshold of two body breaking. This method is applied to the study of some virtual states of the few nucleon system. (L.C.) [pt

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.

Novel Feshbach resonances in a ^40K spin-mixture

Science.gov (United States)

Walraven, J. T. M.; Ludewig, A.; Tiecke, T. G.

2010-03-01

We present experimental results on novel s-wave Feshbach resonances in ^40K spin-mixtures. Using an extended version of the Asymptotic Bound-state Model (ABM) [1] we predict Feshbach resonances with more promising characteristics than the commonly used resonances in the (|F,mF>) |9/2,-9/2>+|9/2,-7/2> and |9/2,-9/2>+|9/2,-5/2> spin mixtures. We report on an s-wave resonance in the |9/2,-5/2>+|9/2,-3/2> mixture. We have experimentally observed the corresponding loss-feature at B0˜178 G with a width of ˜10G. This resonance is promising due to its large predicted width and the absence of an overlapping p-wave resonance. We present our recent results on measurements of the resonance width and the stability of the system around this and other observed s-wave and p-wave resonances. [4pt] [1] T.G. Tiecke, et al., Phys. Rev. Lett. 104, 053202 (2010).

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.

MR imaging of the shoulder: Spectrum of abnormalities in 65 patients and correlation with arthrography and surgery

International Nuclear Information System (INIS)

Zlatkin, M.B.; Reicher, M.A.; Kellerhouse, L.E.; Resnick, D.; Sartoris, D.J.

1987-01-01

MR imaging has previously been used to demonstrate the appearance of the normal shoulder. In this investigation the authors employed MR imaging in 65 consecutive patients with shoulder pain. Subsequent arthrography was performed in 31 patients and surgery in 15. Clinical follow-up was obtained in 35 patients treated conservatively. MR imaging was highly accurate in depicting the spectrum of rotator cuff abnormalities associated with mechanical impingment, including both large and small rotator cuff tears as well as tendinitis. Abnormalities of the capsular mechanisms, osseous tumors, ostenonecrosis, and injuries to the supporting musculature were also well depicted. Considerable potential exists for MR imaging in evaluating shoulder joint disease

Pt skin coated hollow Ag-Pt bimetallic nanoparticles with high catalytic activity for oxygen reduction reaction

Science.gov (United States)

Fu, Tao; Huang, Jianxing; Lai, Shaobo; Zhang, Size; Fang, Jun; Zhao, Jinbao

2017-10-01

The catalytic activity and stability of electrocatalyst is critical for the commercialization of fuel cells, and recent reports reveal the great potential of the hollow structures with Pt skin coat for developing high-powered electrocatalysts due to their highly efficient utilization of the Pt atoms. Here, we provide a novel strategy to prepare the Pt skin coated hollow Ag-Pt structure (Ag-Pt@Pt) of ∼8 nm size at room temperature. As loaded on the graphene, the Ag-Pt@Pt exhibits a remarkable mass activity of 0.864 A/mgPt (at 0.9 V, vs. reversible hydrogen electrode (RHE)) towards oxygen reduction reaction (ORR), which is 5.30 times of the commercial Pt/C catalyst, and the Ag-Pt@Pt also shows a better stability during the ORR catalytic process. The mechanism of this significant enhancement can be attributed to the higher Pt utilization and the unique Pt on Ag-Pt surface structure, which is confirmed by the density functional theory (DFT) calculations and other characterization methods. In conclusion, this original work offers a low-cost and environment-friendly method to prepare a high active electrocatalyst with cheaper price, and this work also discloses the correlation between surface structures and ORR catalytic activity for the hollow structures with Pt skin coat, which can be instructive for designing novel advanced electrocatalysts for fuel cells.

Confluent Crum-Darboux transformations in Dirac Hamiltonians with PT-symmetric Bragg gratings

Czech Academy of Sciences Publication Activity Database

Correa, F.; Jakubský, Vít

2017-01-01

Roč. 95, č. 3 (2017), č. článku 033807. ISSN 2469-9926 R&D Projects: GA ČR(CZ) GJ15-07674Y Institutional support: RVO:61389005 Keywords : PT-symmetric * quantum mechanics * bound states Subject RIV: BE - Theoretical Physics OBOR OECD: Atomic, molecular and chemical physics (physics of atoms and molecules including collision, interaction with radiation, magnetic resonances, Mössbauer effect) Impact factor: 2.925, year: 2016

Rapid thermal annealing of FePt and FePt/Cu thin films

Energy Technology Data Exchange (ETDEWEB)

Brombacher, Christoph

2011-01-10

Chemically ordered FePt is one of the most promising materials to reach the ultimate limitations in storage density of future magnetic recording devices due to its high uniaxial magnetocrystalline anisotropy and a corrosion resistance superior to rare-earth based magnets. In this study, FePt and FePt/Cu bilayers have been sputter deposited at room temperature onto thermally oxidized silicon wafers, glass substrates and self-assembled arrays of spherical SiO{sub 2} particles with diameters down to 10 nm. Millisecond flash lamp annealing, as well as conventional rapid thermal annealing was employed to induce the phase transformation from the chemically disordered A1 phase into the chemically ordered L1{sub 0} phase. The influence of the annealing temperature, annealing time and the film thickness on the ordering transformation and (001) texture evolution of FePt films with near equiatomic composition was studied. Whereas flash lamp annealed FePt films exhibit a polycrystalline morphology with high chemical L1{sub 0} order, rapid thermal annealing can lead to the formation of chemically ordered FePt films with (001) texture on amorphous SiO{sub 2}/Si substrates. The resultant high perpendicular magnetic anisotropy and large coercivities up to 40 kOe are demonstrated. Simultaneously to the ordering transformation, rapid thermal annealing to temperatures exceeding 600 C leads to a break up of the continuous FePt film into separated islands. This dewetting behavior was utilized to create regular arrays of FePt nanostructures on SiO{sub 2} particle templates with periods down to 50 nm. The addition of Cu improves the (001) texture formation and chemical ordering for annealing temperatures T{sub a} {<=}600 C. In addition, the magnetic anisotropy and the coercivity of the ternary FePtCu alloy can be effectively tailored by adjusting the Cu content. The prospects of FePtCu based exchange spring media, as well as the magnetic properties of FePtCu nanostructures fabricated

Shape-dependent surface magnetism of Co-Pt and Fe-Pt nanoparticles from first principles

Science.gov (United States)

Liu, Zhenyu; Wang, Guofeng

2017-12-01

In this paper, we have performed the first-principles density functional theory calculations to predict the magnetic properties of the CoPt and FePt nanoparticles in cuboctahedral, decahedral, and icosahedral shapes. The modeled alloy nanoparticles have a diameter of 1.1 nm and consist of 31 5 d Pt atoms and 24 3 d Co (or Fe) atoms. For both CoPt and FePt, we found that the decahedral nanoparticles had appreciably lower surface magnetic moments than the cuboctahedral and icosahedral nanoparticles. Our analysis indicated that this reduction in the surface magnetism was related to a large contraction of atomic spacing and high local Co (or Fe) concentration in the surface of the decahedral nanoparticles. More interestingly, we predicted that the CoPt and FePt cuboctahedral nanoparticles exhibited dramatically different surface spin structures when noncollinear magnetism was taken into account. Our calculation results revealed that surface anisotropy energy decided the fashion of surface spin canting in the CoPt and FePt nanoparticles, confirming previous predictions from atomistic Monte Carlo simulations.

Study of giant resonances in heavy nuclei

International Nuclear Information System (INIS)

Cataldi, M.I.C.

1986-01-01

The electrodisintegration cross section for 181 Ta, 208 Pb and 209 Bi was measured by counting the emitted neutrons, with incident electrons in the energy range 8-22 MeV. The data was analysed using the virtual photon method, in order to obtain a multipole decomposition and the intensities of Magnetic Dipole and Electric Quadrupole, isoscalar and isovector, in the Giant Resonance. The results obtained for the isovector Giant Quadrupole Resonance are compared with the measured photodisintegration cross section, using data from Saclay and Livermore. This comparision indicates that the photodisintegration data can be well explained assuming an isovector E2 Resonance located between 120 and 130 A -1/3 MeV, with an intensity of one isovector E2 sum. (author) [pt

Synthesis and hydrogenation application of Pt-Pd bimetallic nanocatalysts stabilized by macrocycle-modified dendrimer

Science.gov (United States)

Jin, Zhijun; Xiao, Haiyan; Zhou, Wei; Zhang, Dongqiao; Peng, Xiaohong

2017-12-01

Different generations of poly(propylene imine) (Gn-PPI) terminated with N-containing 15-membered triolefinic macrocycle (GnM) (n = 2, 3, 4, 5) were prepared. The bimetallic nanoparticle catalysts GnM-(Ptx/Pd10-x) (x = 0, 3, 5, 7, 10) were prepared by the synchronous ligand-exchange reaction between GnM and the complexes of Pt(PPh3)4 and Pd(PPh3)4. The structure and catalytic properties of GnM-(Ptx/Pd10-x) were characterized via Fourier transform infrared spectroscopy, 1H nuclear magnetic resonance spectroscopy, X-ray diffraction, X-ray photoelectron spectroscopy, high-resolution transmission electron microscopy, energy-dispersive spectroscopy and inductively coupled plasma atomic emission spectroscopy. The novel bimetallic Pd-Pt nanoparticle catalysts stabilized by dendrimers (DSNs) present higher catalytic activities for the hydrogenation of dimeric acid (DA) than that of nitrile butadiene rubber (NBR). It can be concluded that bimetallic Pd-Pt DSNs possess alloying and synergistic electronic effects on account of the hydrogenation degree (HD) of DA and NBR. Furthermore, the HD of DA and NBR shows a remarkable decrease with the incremental generations (n) of GnM-(Pt3/Pd7) (n = 2, 3, 4, 5).

The anisotropy field of FePt L10 nanoparticles controlled by very thin Pt layer

International Nuclear Information System (INIS)

Okamoto, Satoshi; Kitakami, Osamu; Kikuchi, Nobuaki; Miyazaki, Takamichi; Shimada, Yutaka; Chiang, Te-Hsuan

2004-01-01

We have prepared epitaxial FePt L1 0 (001) nanoparticles covered with Pt [d Pt nm]/Ag[(4-d Pt ) nm] overlayers. The particles are oblate spheroids approximately 10 nm in diameter and 2 nm in height. The anisotropy field H k at 0 K, which is evaluated from the temperature dependences of coercivity H c , decreases from 90 to 60 kOe on increasing the Pt thickness from d Pt 0 to 1.5 nm, while the energy barrier at zero field remains unchanged. The significant reduction of H k due to the presence of the adjacent Pt layer can be attributed to an enhanced magnetic moment caused by the ferromagnetic polarization of Pt atoms at the interface. This finding suggests an effective method of controlling the switching field of FePt L1 0 nanoparticles

Electric-field tunable spin diode FMR in patterned PMN-PT/NiFe structures

Energy Technology Data Exchange (ETDEWEB)

Ziętek, Slawomir, E-mail: zietek@agh.edu.pl; Skowroński, Witold; Stobiecki, Tomasz [AGH University of Science and Technology, Department of Electronics, Al. Mickiewicza 30, 30-059 Kraków (Poland); Ogrodnik, Piotr, E-mail: piotrogr@if.pw.edu.pl [AGH University of Science and Technology, Department of Electronics, Al. Mickiewicza 30, 30-059 Kraków (Poland); Faculty of Physics, Warsaw University of Technology, ul. Koszykowa 75, 00-662 Warszawa (Poland); Stobiecki, Feliks [Institute of Molecular Physics, Polish Academy of Sciences, ul. Smoluchowskiego 17, 60-179 Poznań (Poland); Dijken, Sebastiaan van [NanoSpin, Department of Applied Physics, Aalto University School of Science, P.O. Box 15100, FI-00076 Aalto (Finland); Barnaś, Józef [Faculty of Physics, Adam Mickiewicz University, ul. Umultowska 85, 61-614 Poznań (Poland); Institute of Molecular Physics, Polish Academy of Sciences, ul. Smoluchowskiego 17, 60-179 Poznań (Poland)

2016-08-15

Dynamic properties of NiFe thin films on PMN-PT piezoelectric substrate are investigated using the spin-diode method. Ferromagnetic resonance (FMR) spectra of microstrips with varying width are measured as a function of magnetic field and frequency. The FMR frequency is shown to depend on the electric field applied across the substrate, which induces strain in the NiFe layer. Electric field tunability of up to 100 MHz per 1 kV/cm is achieved. An analytical model based on total energy minimization and the Landau-Lifshitz-Gilbert equation, taking into account the magnetostriction effect, is used to explain the measured dynamics. Based on this model, conditions for optimal electric-field tunable spin diode FMR in patterned NiFe/PMN-PT structures are derived.

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).

Adsorption and oxidation of acetaldehyde on carbon supported Pt, PtSn and PtSn-based trimetallic catalysts by in situ Fourier transform infrared spectroscopy

Science.gov (United States)

Beyhan, Seden; Léger, Jean-Michel; Kadırgan, Figen

2013-11-01

The adsorption and oxidation of acetaldehyde on carbon supported Pt, Pt90Sn10 and Pt80Sn10M10 (M = Ni, Co, Rh, Pd) catalysts have been investigated by using in situ Fourier transform infrared (FTIR) spectroscopy. The result revealed that Pt90Sn10/C catalyst is not very efficient for the conversion of acetaldehyde to CO2 due to the weak adsorption of acetaldehyde in the presence of Sn. However, the addition of a third metal to Pt--Sn facilitates the C-C bond cleavage of acetaldehyde. It seems that acetaldehyde is adsorbed dissociatively on the surface of Pt80Sn10Ni10/C, Pt80Sn10Co10/C, Pt80Sn10Rh10/C catalysts, producing CH3 and CHO adsorbate species, which can be further oxidized to CO2. However, the pathway forming CO2 for Pt80Sn10Pd10/C catalyst mainly originates from the oxidation of CH3CO species. Thus, the presence of third metal in the PtSn catalyst has a strong impact upon the acetaldehyde adsorption behaviour and its reaction products.

Electrocatalytic oxidation of methanol on (Pb) lead modified by Pt, Pt-Ru and Pt-Sn microparticles dispersed into poly(o-phenylenediamine) film

Energy Technology Data Exchange (ETDEWEB)

Golikand, Ahmad Nozad; Maragheh, Mohammad Ghannadi; Irannejad, Leila [Jaber Ibn Hayan Research Lab., Atomic Energy Organization of Iran (AEOI), Tehran (Iran); Golabi, Seyed Mehdi [Electroanalytical Chemistry Lab., Faculty of Chemistry, University of Tabriz, Tabriz (Iran)

2005-08-18

The electrocatalytic oxidation of methanol at a (Pb) lead electrode modified by Pt, Pt-Ru and Pt-Sn microparticles dispersed into poly(o-phenylenediamine) (PoPD) film has been investigated using cyclic voltammetry as analytical technique and 0.5M sulfuric acid as supporting electrolyte. It has been shown that the presence of PoPD film increases considerably the efficiency of deposited Pt and Pt alloys microparticles toward the electrocatalytic oxidation of methanol. The catalytic activity of Pt particles is further enhanced when Ru and especially Sn, is co-deposited in the polymer film. The effects of various parameters such as concentration of methanol, medium temperature as well as the long term stability of modified electrodes have also been investigated. (author)

Surface coverage of Pt atoms on PtCo nanoparticles and catalytic kinetics for oxygen reduction

Energy Technology Data Exchange (ETDEWEB)

Jiang Rongzhong, E-mail: rongzhong.jiang@us.army.mi [Sensors and Electron Devices Directorate, U.S. Army Research Laboratory, 2800 Powder Mill Road, Adelphi, MD 20783-1197 (United States); Rong, Charles; Chu, Deryn [Sensors and Electron Devices Directorate, U.S. Army Research Laboratory, 2800 Powder Mill Road, Adelphi, MD 20783-1197 (United States)

2011-02-01

The surface coverage of Pt atoms on PtCo nanoparticles and its effect on catalytic kinetics for oxygen reduction were investigated. The PtCo nanoparticles with different surface coverage of Pt atoms were synthesized with various methods, including normal chemical method, microemulsion synthesis, and ultrasound-assisted microemulsion. A model of Pt atoms filling into a spherical nanoparticle was proposed to explain the relationship of surface metal atoms and nanoparticle size. The catalytic activity of the PtCo nano-particles is highly dependent on the synthetic methods, even if they have the same chemical composition. The PtCo nano-particles synthesized with ultrasound-assisted microemulsion showed the highest activity, which is attributed to an increase of active surface coverage of Pt atoms on the metal nanoparticles. The rate of oxygen reduction at 0.5 V (vs. SCE) catalyzed by the PtCo synthesized with ultrasound-assisted micro-emulsion was about four times higher than that of the PtCo synthesized with normal chemical method. As demonstrated with rotating-ring disk electrode measurement, the PtCo nano-particles can catalyze oxygen 4-electron reduction to water without intermediate H{sub 2}O{sub 2} detected.

The Diagnostic Reproducibility of Tomosynthesis for the Correlation between Acromiohumeral Distance and Rotator Cuff Size or Type.

Science.gov (United States)

Song, Yoonah; Lee, Seunghun; Lee, Bong Gun; Joo, Young Bin; Song, Soon-Young

2018-01-01

To correlate the acromiohumeral distance (AHD) using tomosynthesis and rotator cuff (RC) pathology and various anatomical indices and to assess the diagnostic reproducibility of tomosynthesis for the evaluation of subacromial impingement. A retrospective review of 63 patients with clinically suspected subacromial impingement was conducted. Two musculoskeletal radiologists independently measured the following quantitative data: the AHD on plain radiographs and the AHD at three compartments (anterior, middle, and posterior) using tomosynthesis, computed tomography (CT) arthrography, or magnetic resonance (MR) arthrography. To investigate the association between the AHD and RC pathology and various anatomical indices, we reviewed the arthroscopic operation record as the referenced standard. The size of rotator cuff tear (RCT) in full-thickness tears displayed a significant inverse correlation with the middle and the posterior tomosynthetic AHDs ( p tomosynthesis, and CT or MR arthrography ( p tomosynthesis is reproducible compared with other modalities.

The influence of temperature in the characterization of nuclear resonance

International Nuclear Information System (INIS)

Campos, T.P.R. de; Martinez, A.S.

1986-01-01

A detailed analysis carried out to determine the temperature effects on the selection of different types of resonance for Resonance Integral calculations is presented. The type of approximation (WR, IR or NR) to be applied to the slowing down integral of the neutron balance equation depends on the relationship between the average energy lost by the neutron and the practical width. A method to include the temperature dependence in the ratio ΔE/GAMMA sub(p) is proposed. The results allowed us to show that this dependence negligence may lead to large errors in the Resonance Integral calculation. (Author) [pt

Preparation and characterization of Pt/C and Pt-Ru/C electrocatalysts for direct ethanol fuel cells

Energy Technology Data Exchange (ETDEWEB)

Liu, Zhaolin; Ling, Xing Yi; Su, Xiaodi; Lee, Jim Yang; Gan, Leong Ming [Institute of Materials Research and Engineering, 3 Research Link, Singapore 117602 (Singapore)

2005-09-26

Nano-sized Pt and Pt-Ru colloids are prepared by a microwave-assisted polyol process, and transferred to a toluene solution of decanthiol. Vulcan XC-72 is then added to the toluene solution to adsorb the thiolated Pt and Pt-Ru colloids. Transmission electron microscopy examinations show nearly spherical particles and narrow size distributions for both supported and unsupported metals. The carbon-supported Pt and Pt-Ru nanoparticles are activated by thermal treatment to remove the thiol stabilizing shell. All Pt and Pt-Ru catalysts (except Pt{sub 23}-Ru{sub 77}) give the X-ray diffraction pattern of a face-centered cubic (fcc) crystal structure, whereas the Pt{sub 23}-Ru{sub 77} alloy is more typical of the hexagonal close packed (hcp) structure. The electro-oxidation of liquid ethanol on these catalysts is investigated at room temperature by cyclic voltammetry. The results demonstrate that the alloy catalyst is catalytically more active than pure platinum. Preliminary tests on a single cell of a direct ethanol fuel cell (DEFC) indicate that a Pt{sub 52}-Ru{sub 48}/C anode catalyst gives the best electrocatalytic performance among all the carbon-supported Pt and Pt-Ru catalysts. (author)

Strongly bound excitons in monolayer PtS2 and PtSe2

KAUST Repository

Sajjad, M.

2018-01-22

Based on first-principles calculations, the structural, electronic, and optical properties of monolayers PtS2 and PtSe2 are investigated. The bond stiffnesses and elastic moduli are determined by means of the spring constants and strain-energy relations, respectively. Dynamic stability is confirmed by calculating the phonon spectra, which shows excellent agreement with experimental reports for the frequencies of the Raman-active modes. The Heyd-Scuseria-Ernzerhof functional results in electronic bandgaps of 2.66 eV for monolayer PtS2 and 1.74 eV for monolayer PtSe2. G0W0 calculations combined with the Bethe-Salpeter equation are used to predict the optical spectra and exciton binding energies (0.78 eV for monolayer PtS2 and 0.60 eV for monolayer PtSe2). It turns out that the excitons are strongly bound and therefore very stable against external perturbations.

Carbon-coated NiPt, CoPt nanoalloys: size control and magnetic properties

Energy Technology Data Exchange (ETDEWEB)

El-Gendy, A.A. [Kirchhoff Institute for Physics, University of Heidelberg, D-69120 Heidelberg (Germany); Leibniz Institute for Solid State and Materials Research (IFW) Dresden (Germany); Hampel, S.; Leonhardt, A.; Khavrus, V.; Buechner, B. [Leibniz Institute for Solid State and Materials Research (IFW) Dresden (Germany); Klingeler, R. [Kirchhoff Institute for Physics, University of Heidelberg, D-69120 Heidelberg (Germany)

2011-07-01

Controlled synthesis of magnetic nanoparticles with well-defined size and composition is always a challenge in material-based nanoscience. Here, we apply the high pressure chemical vapour deposition technique (HPCVD) to obtain carbon-shielded magnetic alloy nanoparticles under control of the particle size. Carbon encapsulated NiPt, CoPt (NiPt rate at C, CoPt rate at C) nanoalloys were synthesized by means of HPCVD starting from sublimating appropriate metal-organic precursors. Structural characterization by means of high resolution transmission electron microscopy, energy dispersive X-ray analysis and X-ray diffraction indicated the formation of coated bimetallic Ni{sub x}Pt{sub 100-x} and CoxPt{sub 100-x} nanoparticles. Adjusting the sublimation temperature of the different precursors allowed tuning the core sizes with small size distribution. In addition, detailed studies of the magnetic properties are presented. AC magnetic heating studies imply the potential of the coated nanoalloys for hyperthermia therapy.

MnO2/CNT supported Pt and PtRu nanocatalysts for direct methanol fuel cells.

Science.gov (United States)

Zhou, Chunmei; Wang, Hongjuan; Peng, Feng; Liang, Jiahua; Yu, Hao; Yang, Jian

2009-07-07

Pt/MnO2/carbon nanotube (CNT) and PtRu/MnO2/CNT nanocomposites were synthesized by successively loading hydrous MnO2 and Pt (or PtRu alloy) nanoparticles on CNTs and were used as anodic catalysts for direct methanol fuel cells (DMFCs). The existence of MnO2 on the surface of CNTs effectively increases the proton conductivity of the catalyst, which then could remarkably improve the performance of the catalyst in methanol electro-oxidation. As a result, Pt/MnO2/CNTs show higher electrochemical active surface area and better methanol electro-oxidation activity, compared with Pt/CNTs. As PtRu alloy nanoparticles were deposited on the surface of MnO2/CNTs instead of Pt, the PtRu/MnO2/CNT catalyst shows not only excellent electro-oxidation activity to methanol with forward anodic peak current density of 901 A/gPt but also good CO oxidation ability with lower preadsorbed CO oxidation onset potential (0.33 V vs Ag/AgCl) and peak potential (0.49 V vs Ag/AgCl) at room temperature.

Fingerprinting ancient gold by measuring Pt with spatially resolved high energy Sy-XRF

International Nuclear Information System (INIS)

Guerra, M.F.; Calligaro, T.; Radtke, M.; Reiche, I.; Riesemeier, H.

2005-01-01

Trace elements of ancient gold such as Pt, give fundamental information on the circulation of the metal in the past. In the case of objects from the cultural heritage, the determination of trace elements requires non-destructive point analysis in general. These conditions and the need of good detection limits restrain the number of applicable analytical techniques. After the development of a PIXE set-up with a selective Cu or Zn filter of 75 μm and of a PIXE-XRF set-up using a primary target of As, we tested the possibilities of spatially resolved Sy-XRF to determine Pt in gold alloys. With a Zn filter, PIXE showed a detection limit of 1000 ppm in gold while PIXE-XRF lowers this detection limit down to 80 ppm. This last value being constrained by the resonant Raman effect produced on gold. In order to improve the detection limit of Pt keeping the non-destructiveness and access to point analysis, we developed an analytical protocol for XRF with synchrotron radiation at BESSY II, using the BAMline set-up. The L-lines of Pt were excited by a beam of energy above and below 11.564 keV and measured using a Si(Li) detector with a 50 μm Cu filter. A μ-beam of 100-250 μm 2 was used according to the size of the sample. The determination of the Pt content in the samples was carried out by Monte-Carlo simulation and subtraction of Au and Pt spectra obtained on pure standards. The limit of detection for Pt of 20 ppm was determined by using certified standards. The detection limits of a small set of other characteristic elements of gold were also measured using an incident energy of 33 keV

Effect of the applied magnetic field and the layer thickness on the magnon properties in bilayers Co/Pt and symmetrical trilayer Pt/Co/Pt

International Nuclear Information System (INIS)

Mehdioui, M.; Fahmi, A.; Lassri, H.; Fahoume, M.; Qachaou, A.

2014-01-01

We have studied the elementary magnetic excitations and their dynamics in multilayer Co(t Co)/Pt(t Pt) and Pt(t Pt)/Co(t Co)/Pt(t Pt) under an applied magnetic field. The Heisenberg hamiltonian used takes into account the magneto-crystalline and surface anisotropies, the exchange and dipolar interactions. The calculated excitation spectrum ε N (k) presents a structure with two sub-bands corresponding to the magnons of surface and volume respectively. The existence of a gap of creating these magnons is also highlighted. The lifetimes deduced from these gaps are in good agreement with the results of previous studies. The thermal evolution of the magnetization m z indicates that the system undergoes a dimensional crossover 3D–2D when the temperature increases. The calculated and measured magnetizations are compared and they are in good agreement. The exchange integral and critical temperature values deduced from these adjustments are in very good agreement with the results of previous works. - Highlights: • The magnons of surface and volume exist in Co/Pt and Pt/Co/Pt. • Samples undergo dimensional crossover (3D–2D) when T increases. • A good agreement is obtained between M(T) measured and calculated. • Deduced exchange integrals and critical temperature values are correct. • The magnetism of the sample is reduced by increasing t Pt or capping Co by two Pt layers

Characteristics of ferroelectric Pb(Zr,Ti)O3 thin films having Pt/PtOx electrode barriers

International Nuclear Information System (INIS)

Lee, Kwangbae; Rhee, Byung Roh; Lee, Chanku

2001-01-01

We have investigated the feasibility of the Pt/PtO x multilayer as an electrode barrier for Pb(Zr,Ti)O 3 (PZT)-based ferroelectric random access memories. PtO x and Pt layers were prepared on polycrystalline-Si/SiO 2 /Si substrates by means of the sputtering method in Ar and O 2 ambience, and the Pb(Zr 0.53 Ti 0.47 )O 3 layer was prepared by the sol-gel method. A capacitor consisting of Pt/PtO x /PZT/PtO x /Pt/PtO x /poly-Si had a remanent polarization of 18 μC/cm 2 and a low coercive field of 32 kV/cm. The polarization fatigue behavior of test capacitors was improved as compared with that of Pt/PZT/Pt, which showed negligible fatigue loss of 15% after 10 11 switching repetitions with a frequency of 1 MHz. Copyright 2001 American Institute of Physics

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...

Electron paramagnetic resonance: A new method of quaternary dating

International Nuclear Information System (INIS)

Poupeau, G.; Rossi, A.; Teles, M.M.; Danon, J.

1984-01-01

Significant progress has occurred in the last years in quaternary geochronology. One of this is the emergence of a new dating approach, the Electron Spin Resonance Method. The aim of this paper is to briefly review the method and discuss some aspects of the work at CBPF. (Author) [pt

Electron paramagnetic resonance: a new method of quaternary dating

International Nuclear Information System (INIS)

Poupeau, G.; Rossi, A.; Universidade Federal Rural do Rio de Janeiro; Telles, M.; Danon, J.

1984-01-01

Significant progress has occurred in the last years in quaternary geochronology. One of this is the emergence of a new dating approach, the Electron Spin Resonance Method. The aim of this paper is to briefly review the method and discuss some aspects of the work at CBPF. (Author) [pt

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.

Reaction of cyanide with Pt-nucleobase complexes: preparative, spectroscopic, and structural studies. Unexpected stability of Pt-thymine and Pt-uracil complexes

International Nuclear Information System (INIS)

Raudaschl-Sieber, G.; Lippert, B.

1985-01-01

In order to improve the understanding of the nature of the strongly bound cisplatin on DNA, the reactivity of a large number of complexes of cis-(NH 3 ) 2 Pt/sup II/ with the model nucleobases, 9-ethylguanine, 9-methyladenine, 1-methylcytisine, 1-methylthymine, and i-methyluracil, toward a large excess of cyanide was studied. The behavior of Pt-nucleobase complexes toward CN - is compared with that of simple Pt-amine complexes, and reactions of thiourea with two selected nucleobase complexes is reported. The relevance of these findings with respect to substitution reactions of Pt-nucleobase complexes and the nature of the tightly DNA-bound Pt, which cannot be removed by excess KCN, is discussed

Unravelling the dependence of hydrogen oxidation kinetics on the size of Pt nanoparticles by in operando nanoplasmonic temperature sensing

DEFF Research Database (Denmark)

Wettergren, Kristina; Hellman, Anders; Cavalca, Filippo Carlo

2015-01-01

We use a noninvasive nanoscale optical-temperature measurement method based on localized surface plasmon resonance to investigate the particle size-dependence of the hydrogen oxidation reaction kinetics on model supported Pt nanocatalysts at atmospheric pressure in operando. With decreasing average...

Efficient decomposition of formaldehyde at room temperature over Pt/honeycomb ceramics with ultra-low Pt content.

Science.gov (United States)

Nie, Longhui; Zheng, Yingqiu; Yu, Jiaguo

2014-09-14

Pt/honeycomb ceramic (Pt/HC) catalysts with ultra-low Pt content (0.005-0.055 wt%) were for the first time prepared by an impregnation of honeycomb ceramics with Pt precursor and NaBH4-reduction combined method. The microstructures, morphologies and textural properties of the resulting samples were characterized by X-ray diffraction (XRD), field-emission scanning electron microscopy (FE-SEM), and transmission electron microscopy (TEM). The obtained Pt/HC catalysts were used for catalytic oxidative decomposition of formaldehyde (HCHO) at room temperature. It was found that the as-prepared Pt/HC catalysts can efficiently decompose HCHO in air into CO2 and H2O at room temperature. The catalytic activity of the Pt/HC catalysts increases with increasing the Pt loading in the range of 0.005-0.013 wt%, and the further increase of the Pt loading does not obviously improve catalytic activity. From the viewpoint of cost and catalytic performance, 0.013 wt% Pt loading is the optimal Pt loading amount, and the Pt/HC catalyst with 0.013 wt% Pt loading also exhibited good catalytic stability. Considering practical applications, this work will provide new insights into the low-cost and large-scale fabrication of advanced catalytic materials for indoor air purification.

Microwave sinthesys and characterization of Pt and Pt-Rh-Sn electrocatalysts for ethanol oxidation

Directory of Open Access Journals (Sweden)

Jovanović Vladislava M.

2011-01-01

Full Text Available Carbon supported Pt and Pt-Rh-Sn catalysts were synthesized by microwave-polyol method in ethylene glycol solution and investigated for the ethanol electro-oxidation reaction. The catalysts were characterized in terms of structure, morphology and composition by employing XRD, STM and EDX techniques. STM analysis indicated rather uniform particles and particle size of below 2 nm for both catalysts. XRD analysis of the Pt/C catalyst revealed two phases, one with the main characteristic peaks of face centered cubic crystal structure (fcc of platinum and another related to graphite like structure of carbon support Vulcan XC-72R. However, in XRD pattern of the Pt-Rh-Sn/C catalyst diffraction peaks for Pt, Rh or Sn cannot be resolved, indicating an extremely low crystallinity. The small particle sizes and homogeneous size distributions of both catalysts should be attributed to the advantages of microwave assisted modified polyol process in ethylene glycol solution. Pt-Rh- Sn/C catalyst is highly active for the ethanol oxidation with the onset potential shifted for more than 150 mV to negative values and with currents nearly 5 times higher in comparison to Pt/C catalyst. The stability tests of the catalysts, as studied by the chronoamperometric experiments, reveal that the Pt-Rh-Sn/C catalyst is evidently less poisoned then Pt/C catalyst. The increased activity of Pt-Rh-Sn/C in comparison to Pt/C catalyst is most probably promoted by bifunctional mechanism and the electronic effect of alloyed metals.

Structure and electrical properties of Pb(ZrxTi1-x)O3 deposited on textured Pt thin films

International Nuclear Information System (INIS)

Hong, Jongin; Song, Han Wook; Lee, Hee Chul; Lee, Won Jong; No, Kwangsoo

2001-01-01

The texturing of the bottom electrode plays a key role in the structure and electrical properties of Pb(Zr,Ti)O 3 (PZT) thin films. We fabricated Pt bottom electrodes having a different thickness on MgO single crystals at 600 o C by rf magnetron sputtering. As the thickness of platinum (Pt) thin film increased, the preferred orientation of Pt thin film changed from (200) to (111). PZT thin films were fabricated at 450 o C by electron cyclotron resonance-plasma enhanced metal organic chemical vapor deposition on the textured Pt thin films. The texturing of the bottom electrode caused drastic changes in the C--V characteristics, P--E characteristics, and fatigue characteristics of metal/ferroelectric material/metal (MFM) capacitors. The difference of the electrical properties between the PZT thin films having different texturing was discussed in terms-of the x--y alignment and the interface between electrode and PZT in MFM capacitors. copyright 2001 American Institute of Physics

Giant dipole resonance by many levels theory

International Nuclear Information System (INIS)

Mondaini, R.P.

1977-01-01

The many levels theory is applied to photonuclear effect, in particular, in giant dipole resonance. A review about photonuclear dipole absorption, comparing with atomic case is done. The derivation of sum rules; their modifications by introduction of the concepts of effective charges and mass and the Siegert theorem. The experimental distributions are compared with results obtained by curve adjustment. (M.C.K.) [pt

Time-invariant PT product and phase locking in PT -symmetric lattice models

Science.gov (United States)

Joglekar, Yogesh N.; Onanga, Franck Assogba; Harter, Andrew K.

2018-01-01

Over the past decade, non-Hermitian, PT -symmetric Hamiltonians have been investigated as candidates for both a fundamental, unitary, quantum theory and open systems with a nonunitary time evolution. In this paper, we investigate the implications of the former approach in the context of the latter. Motivated by the invariance of the PT (inner) product under time evolution, we discuss the dynamics of wave-function phases in a wide range of PT -symmetric lattice models. In particular, we numerically show that, starting with a random initial state, a universal, gain-site location dependent locking between wave-function phases at adjacent sites occurs in the PT -symmetry-broken region. Our results pave the way towards understanding the physically observable implications of time invariants in the nonunitary dynamics produced by PT -symmetric Hamiltonians.

Pt/Cr and Pt/Ni catalysts for oxygen reduction reaction: to alloy or not to alloy?

Science.gov (United States)

Escaño, Mary Clare; Gyenge, Elod; Nakanishi, Hiroshi; Kasai, Hideaki

2011-04-01

Bimetallic systems such as Pt-based alloys or non-alloys have exhibited interesting catalytic properties but pose a major challenge of not knowing a priori how the electronic and chemical properties will be modified relative to the parent metals. In this work, we present the origin of the changes in the reactivity of Pt/Cr and Pt/Ni catalysts, which have been of wide interest in fuel cell research. Using spin-polarized density functional theory calculations, we have shown that the modification of Pt surface reactivity in Pt/Ni is purely of geometric origin (strain). We have also found that the Pt-Ni bonding is very weak, which explains the observed instability of Pt-Ni catalysts under electrochemical measurements. On the other hand, Pt/Cr systems are governed by strong ligand effect (metal-metal interaction), which explains the experimentally observed reactivity dependence on the relative composition of the alloying components. The general characteristics of the potential energy curves for O2 dissociative adsorption on the bimetallic systems and the pure Pt clarify why the d-band center still works for Pt/Cr despite the strong Pt-Cr bonding and high spin polarization of Pt d-states. On the basis of the above clarifications, viable Pt-Cr and Pt-Ni structures, which involve nano-sized alloys and non-alloy bulk catalyst, which may strike higher than the currently observed oxidation reduction reaction activity are proposed.

Electro-oxidation of methanol and ethanol using PtRu/C, PtSn/C and PtSnRu/C electrocatalysts prepared by an alcohol-reduction process

Science.gov (United States)

Neto, Almir Oliveira; Dias, Ricardo R.; Tusi, Marcelo M.; Linardi, Marcelo; Spinacé, Estevam V.

PtRu/C, PtSn/C and PtSnRu/C electrocatalysts were prepared by the alcohol reduction process using ethylene glycol as the solvent and reduction agent and Vulcan Carbon XC72 as the support. The electrocatalysts were characterized by EDX, XRD and cyclic voltammetry. The electrochemical oxidation of methanol and ethanol were studied by chronoamperometry using a thin porous coating technique. The PtSn/C electrocatalyst prepared by this methodology showed superior performance compared to the PtRu/C and PtSnRu/C electrocatalysts for methanol and ethanol oxidation at room temperature.

Evaluation of 2-point, 3-point, and 6-point Dixon magnetic resonance imaging with flexible echo timing for muscle fat quantification.

Science.gov (United States)

Grimm, Alexandra; Meyer, Heiko; Nickel, Marcel D; Nittka, Mathias; Raithel, Esther; Chaudry, Oliver; Friedberger, Andreas; Uder, Michael; Kemmler, Wolfgang; Quick, Harald H; Engelke, Klaus

2018-06-01

The purpose of this study is to evaluate and compare 2-point (2pt), 3-point (3pt), and 6-point (6pt) Dixon magnetic resonance imaging (MRI) sequences with flexible echo times (TE) to measure proton density fat fraction (PDFF) within muscles. Two subject groups were recruited (G1: 23 young and healthy men, 31 ± 6 years; G2: 50 elderly men, sarcopenic, 77 ± 5 years). A 3-T MRI system was used to perform Dixon imaging on the left thigh. PDFF was measured with six Dixon prototype sequences: 2pt, 3pt, and 6pt sequences once with optimal TEs (in- and opposed-phase echo times), lower resolution, and higher bandwidth (optTE sequences) and once with higher image resolution (highRes sequences) and shortest possible TE, respectively. Intra-fascia PDFF content was determined. To evaluate the comparability among the sequences, Bland-Altman analysis was performed. The highRes 6pt Dixon sequences served as reference as a high correlation of this sequence to magnetic resonance spectroscopy has been shown before. The PDFF difference between the highRes 6pt Dixon sequence and the optTE 6pt, both 3pt, and the optTE 2pt was low (between 2.2% and 4.4%), however, not to the highRes 2pt Dixon sequence (33%). For the optTE sequences, difference decreased with the number of echoes used. In conclusion, for Dixon sequences with more than two echoes, the fat fraction measurement was reliable with arbitrary echo times, while for 2pt Dixon sequences, it was reliable with dedicated in- and opposed-phase echo timing. Copyright © 2018 Elsevier B.V. All rights reserved.

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 ( ...

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.

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

International Nuclear Information System (INIS)

Zoellner, Frank G.; Kalayciyan, Raffi; Chacon-Caldera, Jorge; Zimmer, Fabian; Schad, Lothar R.

2014-01-01

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.

MR imaging of hyaline cartilage in chondromalacia patellae and osteochondrosis dissecans: A comparison with CT-arthrography and arthroscopy

International Nuclear Information System (INIS)

Lehner, K.; Heuck, A.; Lukas, P.; Rodammer, G.; Allgayer, B.; Pasquay, E.

1987-01-01

Superior to spin-echo sequences, the articular hyaline cartilage was imaged with fast-field-echo sequences (FFE, Gyroscan 0.5-T, Philips) with an excitation pulse angle of 40 0 to 60 0 . Chondromalaceous lesions could be demonstrated in 30 patients with chondropathia patellae with the same sensitivity compared with CT arthrography. In a further 50 patients with osteochondrosis dissecans, discontinuities of the cartilage could be predicted using the deeply invading articular fluid as an indicator. The sensitivity of MR imaging, as controlled by arthroscopy, was very high in that respect. Separate from the nonhemorrhagic articular fluid, the cartilaginous defects could be imaged directly by variation of the FFE parameters

Damping constant of Co/Pt multilayer thin-film media

Energy Technology Data Exchange (ETDEWEB)

Fujita, N. [Yamagata University, 4-3-16 Jonan, Yonezawa, Yamagata 992-8510 (Japan); Inaba, N. [Yamagata University, 4-3-16 Jonan, Yonezawa, Yamagata 992-8510 (Japan)], E-mail: inaba@yz.yamagata-u.ac.jp; Kirino, F. [National University of Fine Arts and Music, 2-12-1 Ookayama, Meguro-ku, Tokyo 152-8577 (Japan); Igarashi, S.; Koike, K.; Kato, H. [Yamagata University, 4-3-16 Jonan, Yonezawa, Yamagata 992-8510 (Japan)

2008-11-15

Gilbert's damping constants, {alpha}, of Co(t{sub Co})/Pt (1.4 nm) multilayer thin films are investigated by Q-band FMR analysis. {alpha} is calculated from the resonance width of the FMR spectrum. With decreasing t{sub Co}, the {alpha} value decreases from 0.034 (t{sub Co}=8.7 nm) to 0.023 (t{sub Co}=1.8 nm), and then increases to 0.037 (t{sub Co}=1.0 nm). The decrease of {alpha} with t{sub Co}>1.8 nm is probably due to the eddy current loss effects. The increase of {alpha} with t{sub Co}<1.8 nm would be caused by the increase of the distortion between the Co and the Pt layers at the interface. When the magnetic field direction was changed from {theta}=90 deg. (parallel to the specimen) to {theta}=0 deg. (perpendicular to the specimen), the {alpha} of all the specimens increased, and a sharp step in {alpha} was observed around {theta}=40 deg., where the {alpha} has the maximum value.

Atom distribution and interactions in Ag{sub x}Pt{sub 1-x} and Au{sub x}Pt{sub 1-x} surface alloys on Pt(111)

Energy Technology Data Exchange (ETDEWEB)

Roetter, Ralf T.; Bergbreiter, Andreas; Hoster, Harry E.; Behm, R. Juergen [Institute of Surface Chemistry and Catalysis, Ulm University, D-89069 Ulm (Germany)

2009-07-01

The atom distributions in Ag{sub x}Pt{sub 1-x}/Pt(111) and Au{sub x}Pt{sub 1-x}/Pt(111) surface alloys were studied by high resolution UHV-STM. These surfaces were prepared by submonolayer Ag (Au) metal deposition on Pt(111), followed by annealing at 900 K or 1000 K, respectively, which in both cases results in surface confined 2D alloys, with equilibrated distribution of the components. Both systems show a tendency towards two-dimensional clustering, which fits well to their known bulk immiscibility. Effective cluster interactions (ECIs) will be derived by a quantitative evaluation of the 2D atom distributions in the surface alloys. By comparing the ECIs for PtAg and PtAu on Pt(111), and considering that Ag and Au have almost similar lattice constants, the results allow conclusion on the physical origin of the tendency for clustering.

Nuclear quadrupole resonance of arsenolite

International Nuclear Information System (INIS)

Madarazo, R.

1988-01-01

A pulsed Nuclear Quadrupole Resonance (NQR) spectrometer was constructed using imported Matec units. Peripherical components were specially assembled and tested for the implantation of the spin-echo technique in the Laboratorio de Centros de Cor of IFUSP. The R.F. operation range is from 50 to 1 ) and spin-spin (T 2 ) relaxation times were carried out at room temperature in arsenolite. The 75 As NQR frequency measured at room temperature is 116.223 MHz. (author) [pt

Some examples of utilization of electron paramagnetic resonance in biology

International Nuclear Information System (INIS)

Bemski, G.

1982-10-01

A short outline of the fundamentals of electron paramagnetic resonance (EPR) is presented and is followed by examples of the application of EPR to biology. These include use of spin labels, as well as of ENDOR principally to problems of heme proteins, photosynthesis and lipids. (Author) [pt

Multifunctional Pt(II) Reagents: Covalent Modifications of Pt Complexes Enable Diverse Structural Variation and In-Cell Detection.

Science.gov (United States)

White, Jonathan D; Haley, Michael M; DeRose, Victoria J

2016-01-19

To enhance the functionality of Pt-based reagents, several strategies have been developed that utilize Pt compounds modified with small, reactive handles. This Account encapsulates work done by us and other groups regarding the use of Pt(II) compounds with reactive handles for subsequent elaboration with fluorophores or other functional moieties. Described strategies include the incorporation of substituents for well-known condensation or nucleophilic displacement-type reactions and their use, for example, to tether spectroscopic handles to Pt reagents for in vivo investigation. Other chief uses of displacement-type reactions have included tethering various small molecules exhibiting pharmacological activity directly to Pt, thus adding synergistic effects. Click chemistry-based ligation techniques have also been applied, primarily with azide- and alkyne-appended Pt complexes. Orthogonally reactive click chemistry reactions have proven invaluable when more traditional nucleophilic displacement reactions induce side-reactivity with the Pt center or when systematic functionalization of a larger number of Pt complexes is desired. Additionally, a diverse assortment of Pt-fluorophore conjugates have been tethered via click chemistry conjugation. In addition to providing a convenient synthetic path for diversifying Pt compounds, the use of click-capable Pt complexes has proved a powerful strategy for postbinding covalent modification and detection with fluorescent probes. This strategy bypasses undesirable influences of the fluorophore camouflaged as reactivity due to Pt that may be present when detecting preattached Pt-fluorophore conjugates. Using postbinding strategies, Pt reagent distributions in HeLa and lung carcinoma (NCI-H460) cell cultures were observed with two different azide-modified Pt compounds, a monofunctional Pt(II)-acridine type and a difunctional Pt(II)-neutral complex. In addition, cellular distribution was observed with an alkyne-appended difunctional

Preparation and characterization of Pt/C and Pt sbnd Ru/C electrocatalysts for direct ethanol fuel cells

Science.gov (United States)

Liu, Zhaolin; Ling, Xing Yi; Su, Xiaodi; Lee, Jim Yang; Gan, Leong Ming

Nano-sized Pt and Pt sbnd Ru colloids are prepared by a microwave-assisted polyol process, and transferred to a toluene solution of decanthiol. Vulcan XC-72 is then added to the toluene solution to adsorb the thiolated Pt and Pt sbnd Ru colloids. Transmission electron microscopy examinations show nearly spherical particles and narrow size distributions for both supported and unsupported metals. The carbon-supported Pt and Pt sbnd Ru nanoparticles are activated by thermal treatment to remove the thiol stabilizing shell. All Pt and Pt sbnd Ru catalysts (except Pt 23sbnd Ru 77) give the X-ray diffraction pattern of a face-centered cubic (fcc) crystal structure, whereas the Pt 23sbnd Ru 77 alloy is more typical of the hexagonal close packed (hcp) structure. The electro-oxidation of liquid ethanol on these catalysts is investigated at room temperature by cyclic voltammetry. The results demonstrate that the alloy catalyst is catalytically more active than pure platinum. Preliminary tests on a single cell of a direct ethanol fuel cell (DEFC) indicate that a Pt 52sbnd Ru 48/C anode catalyst gives the best electrocatalytic performance among all the carbon-supported Pt and Pt sbnd Ru catalysts.

Electro-oxidation of methanol and ethanol using PtRu/C, PtSn/C and PtSnRu/C electrocatalysts prepared by an alcohol-reduction process

Energy Technology Data Exchange (ETDEWEB)

Neto, Almir Oliveira; Dias, Ricardo R.; Tusi, Marcelo M.; Linardi, Marcelo; Spinace, Estevam V. [Instituto de Pesquisas Energeticas e Nucleares, IPEN-CNEN/SP, Av. Prof. Lineu Prestes 2242, Cidade Universitaria, CEP 05508-900 Sao Paulo, SP (Brazil)

2007-03-30

PtRu/C, PtSn/C and PtSnRu/C electrocatalysts were prepared by the alcohol reduction process using ethylene glycol as the solvent and reduction agent and Vulcan Carbon XC72 as the support. The electrocatalysts were characterized by EDX, XRD and cyclic voltammetry. The electrochemical oxidation of methanol and ethanol were studied by chronoamperometry using a thin porous coating technique. The PtSn/C electrocatalyst prepared by this methodology showed superior performance compared to the PtRu/C and PtSnRu/C electrocatalysts for methanol and ethanol oxidation at room temperature. (author)

Ion-irradiation induced chemical ordering of FePt and FePtAu nanoparticles

Energy Technology Data Exchange (ETDEWEB)

Seetala, Naidu V. [Department of Physics, Grambling State University, RWE Jones Drive, Carver Hall 81, Grambling, LA 71245 (United States)]. E-mail: naidusv@gram.edu; Harrell, J.W. [MINT Center, University of Alabama, Tuscaloosa, AL 35487 (United States); Lawson, Jeremy [MINT Center, University of Alabama, Tuscaloosa, AL 35487 (United States); Nikles, David E. [MINT Center, University of Alabama, Tuscaloosa, AL 35487 (United States); Williams, John R. [Department of Physics, Auburn University, Auburn, AL 36849 (United States); Isaacs-Smith, Tamara [Department of Physics, Auburn University, Auburn, AL 36849 (United States)

2005-12-15

We have studied the effect of ion-beam irradiation on reducing the ordering temperature of FePt and FePtAu nanoparticles. FePt and FePt(Au14%) 4 nm particles dispersed on a Si-substrate were irradiated by 300 keV Al-ions with a dose of 1 x 10{sup 16} ions/cm{sup 2} at 43 {sup o}C using a water-cooled flange in order to minimize the vacancy migration and voids formation within the collision cascades. Partial chemical ordering has been observed in as-irradiated particles with coercivity of 60-130 Oe. Post-irradiation annealing at 220 {sup o}C enhanced chemical ordering in FePt nanoparticles with coercivity of 3500 Oe, magnetic anisotropy of 1.5 x 10{sup 7} erg/cc, and thermal stability factor of 130. A much higher 375 {sup o}C post-irradiation annealing was required in FePtAu, presumably because Au atoms were trapped at Fe/Pt lattice sites at lower temperatures. As the annealing temperature increased, anomalous features in the magnetization reversal curves were observed that disappeared at higher annealing temperatures.

Electrocatalytic activity of Pt and PtCo deposited on Ebonex by BH reduction

International Nuclear Information System (INIS)

Slavcheva, E.; Nikolova, V.; Petkova, T.; Lefterova, E.; Dragieva, I.; Vitanov, T.; Budevski, E.

2005-01-01

The method of borohydride reduction (BH) has been applied to synthesize Pt and PtCo nanoparticles supported on Magneli phase titanium oxides, using Pt and Co ethylenediamine complexes as metal precursors. The phase composition of the synthesized catalysts, their morphology and surface structure were studied by physical methods for bulk and surface analysis, such as electron microprobe analysis (EMPA), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS) and BET technique. The catalytic activity towards oxygen evolution reaction in alkaline aqueous solution was investigated using the common electrochemical techniques. It was found that PtCo/Ebonex facilitates essentially the oxygen evolution which starts at lower overpotentials and proceeds with higher rate compared to both the supported Pt and unsupported PtCo catalysts. The observed effect is prescribed to metal-metal and metal-support interactions. The Ebonex possesses a good electrical conductivity and corrosion resistance at high anodic potentials and despite its low surface area is considered as a potential catalyst carrier for the oxygen evolution reaction