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Sample records for magnetic resonance arthrography

  1. Evaluation of TFC tears with magnetic resonance imaging; Comparison with arthrography

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    Kushida, Manabu; Imamura, Koutaro; Sumi, Mitsuhiro; Uetani, Masataka (Nagasaki Univ. (Japan). School of Medicine); Nagatani, Yoshifumi

    1993-09-01

    This study evaluated the accuracy of magnetic resonance imaging (MRI) in the detection of tears of the trianglar fibrocartilage (TFC). Eighteen patients with chronic pain in the ulnar side of their wrist were examined by MRI and arthrography. Compared with arthrography, MRI was effective in the evaluation of TFC tears with a sensitivity of 92%, a specificity of 67%, and an accuracy of 83%. (author).

  2. All-in-One Magnetic Resonance Arthrography of the Shoulder in a Vertically Open Magnetic Resonance Unit

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    Vandevenne, J.E.; Vanhoenacker, F.; Beaulieu, C.F.; Bergman, A.; Butts Pauly, K.; Dillingham, M.F.; Lang, P.K. (Dept. of Radiology, Univ. Hospital Antwerp, Edegem-Antwerp (Belgium))

    2008-10-15

    Background: Magnetic resonance (MR) arthrography frequently involves joint injection under imaging guidance followed by MR imaging in static positions. Purpose: To evaluate if MR arthrography of the shoulder joint can be performed in a comprehensive fashion combining the MR-guided injection procedure, static MR imaging, and dynamic motion MR imaging in a single test. Material and Methods: Twenty-three shoulder joints were injected with Gd-DTPA2- under MR guidance. Static MR imaging was performed and included a three-point Dixon method to achieve water-selective images. Dynamic motion MR imaging with and without applying pressure to the upper arm was used to evaluate glenohumeral joint instability. In 10 cases, surgical correlation was available. Results: The all-in-one MR arthrography technique was successful in all patients, and took an average time of 65 min. All but one glenohumeral injection procedure were performed with a single needle pass, and no complications were observed. Out of eight labrum tears seen with static MR imaging, seven were confirmed at surgery. In 10 cases, dynamic motion MR imaging correlated well with the surgeon's intraoperative evaluation for presence and direction of instability. Conclusion: MR arthrography of the shoulder joint using a vertically open magnet can be performed as a single comprehensive test, including the injection and the static and dynamic motion MR imaging. Good diagnostic accuracy for intraarticular lesions and glenohumeral instability was found in a small sample.

  3. Arthrography

    Medline Plus

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

  4. Magnetic resonance arthrography in chronic wrist pain

    International Nuclear Information System (INIS)

    Valeri, G.; Ferrara, C.; Carloni, S.

    1999-01-01

    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 [it

  5. 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.

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

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

    2007-11-15

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

  7. Arthrography

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    Full Text Available ... injected into the joint. Arthrography may use computed tomography (CT) scanning, magnetic resonance imaging (MRI) or fluoroscopy – ... also use magnetic resonance imaging (MRI) or computed tomography (CT) following contrast material injection into the joint. ...

  8. Arthrography

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    Full Text Available ... injected into the joint. Arthrography may use computed tomography (CT) scanning, magnetic resonance imaging (MRI) or fluoroscopy – a ... also use magnetic resonance imaging (MRI) or computed tomography (CT) following contrast material injection into the joint. An ...

  9. 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.

  10. 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

  11. 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.

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

    International Nuclear Information System (INIS)

    Dyck, P. van; Gielen, J.L.; Parizel, P.M.

    2009-01-01

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

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

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

    2009-11-15

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

  14. Arthrography

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    Full Text Available ... may be used to guide the procedure. Alternate methods of direct arthrography examinations may also use magnetic resonance imaging (MRI) or computed tomography (CT) following ...

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

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    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.)

  16. Arthrography

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    Full Text Available ... guide the procedure. Alternate methods of direct arthrography examinations may also use magnetic resonance imaging (MRI) or ... the injection is typically monitored by fluoroscopy, the examination also commonly involves taking radiographs for documentation. These ...

  17. 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.

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

    International Nuclear Information System (INIS)

    Hahn, Seok; Lee, Young Han; Suh, Jin Suck

    2016-01-01

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

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

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

    2016-12-15

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

  20. Rotator cuff tears noncontrast MRI compared to MR arthrography

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

    2015-12-15

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

  1. Rotator cuff tears noncontrast MRI compared to MR arthrography

    International Nuclear Information System (INIS)

    Lee, Ji Hyun; Yoon, Young Cheol; Jung, Jee Young; Yoo, Jae Chul

    2015-01-01

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

  2. 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.

  3. 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.)

  4. Evaluation of the triangular fibrocartilage complex tears by arthrography and MR imaging

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    Sakai, Makoto; Shibata, Yasushi [Hokkaido Kin-i-kyou Central Hospital, Sapporo (Japan); Takahata, Naoji

    1995-08-01

    Arthroscopic or open surgical findings in 21 wrists with chronic ulnar painful lesion were compared both with arthrography and magnetic resonance (MR) imaging results to evaluate the accuracy of the two diagnostic procedures in the detection of triangular fibrocartilage complex (TFCC) lesions. Arthrography investigations were performed for the 20 wrists but one that had allergy for iodine and MR imagings were performed for the recent 12 wrists. Arthrography and magnetic resonance (MR) imaging were almost equally useful for the detection of the TFCC injury and their injury sites. (author).

  5. 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

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

    Energy Technology Data Exchange (ETDEWEB)

    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.

  7. 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

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2012-09-15

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

  9. 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.)

  10. MR arthrography: how I do it

    International Nuclear Information System (INIS)

    Bankaoglu, M.

    2012-01-01

    Full text: Magnetic resonance imaging has to rely on improving new various sequences and techniques and to get the best imaging quality so magnetic resonance (MR) arthrography is one of the most important technique in the assessment of selected musculoskeletal disorders. It is now widely utilized and considered by most musculoskeletal radiologists and some orthopedists to be an integral part of their clinical practice. The technique include: desired degree of joint distension with contrast medium; markedly improved imaging quality of intra-articular structures with the direct delineation so improved detection of pathology with MRI. As appliance and technique of MR arthrography is completely based on traditional arthrography of X ray. In MR arthrography additional very little amount of Gadolinium based contrast agent is added to the desired mixture of contrast material injected to the joint. As in conventional radiography MR arthrography is used to get extra information for conventional MRI . Practically any joint that can be accessed by a needle can be imaged using MR arthrography but it has been applied to limited number of joints to compare with the traditional arthrography so shoulder, knee, wrist, elbow, ankle, and hip are mostly subjects to do in MR arthrography. The procedure is also less invasive and expensive rather than diagnostic arthroscopy and should carefully indicated because it is not completely noninvasive technique so previous imaging modalities and MRI of the patients should be completed and evaluated well. During or after the procedure there has been no major complication reported by so far but more than two third of patients are known to complain some degree of pain right after or several times later than the procedure. As it is more than twenty years now it has been widely accepted helpful for diagnosis and adds some extra sensitivity to conventional MRI . Up to this time MR arthrography has proven to increase sensitivity of conventional MRI in

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2010-07-15

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

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

    Energy Technology Data Exchange (ETDEWEB)

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

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

  13. 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)

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

    Energy Technology Data Exchange (ETDEWEB)

    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

  15. 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

  16. 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.

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

    Directory of Open Access Journals (Sweden)

    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.

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

    Energy Technology Data Exchange (ETDEWEB)

    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.).

  19. 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)

  20. 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

  1. 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)

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

    Energy Technology Data Exchange (ETDEWEB)

    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.)

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2015-05-01

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

  4. 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.)

  5. 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

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

    Directory of Open Access Journals (Sweden)

    Shivani Pahwa

    2014-01-01

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

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

    Energy Technology Data Exchange (ETDEWEB)

    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.

  8. 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

  9. 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.)

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2002-05-01

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

  11. Arthrography

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    Full Text Available ... News Physician Resources Professions Site Index A-Z Direct Arthrography Arthrography is a type of medical imaging ... are the limitations of Direct Arthrography? What is Direct Arthrography? Arthrography is medical imaging to evaluate conditions ...

  12. Arthrography

    Medline Plus

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

  13. 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)

  14. MRI and arthrography in the evaluation of TMJ disorders

    Energy Technology Data Exchange (ETDEWEB)

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

    1991-08-01

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

  15. 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)

  16. 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

  17. 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.)

  18. 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.)

  19. 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.)

  20. 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.)

  1. 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

  2. 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.)

  3. Arthrography

    Medline Plus

    Full Text Available ... risks? What are the limitations of Direct Arthrography? What is Direct Arthrography? Arthrography is medical imaging to ... a computer using x-rays. top of page What are some common uses of the procedure? Arthrographic ...

  4. 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.)

  5. 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.)

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

    Energy Technology Data Exchange (ETDEWEB)

    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

  7. 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

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2006-06-15

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

  9. 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)

  10. 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.

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

    Energy Technology Data Exchange (ETDEWEB)

    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).

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

    Directory of Open Access Journals (Sweden)

    Heba Ahmed Kamal

    2014-09-01

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

  13. Arthrography

    Medline Plus

    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 ...

  14. Arthrography

    Medline Plus

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

  15. Arthrography

    Medline Plus

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

  16. Arthrography

    Medline Plus

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

  17. 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.)

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

    Energy Technology Data Exchange (ETDEWEB)

    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.)

  19. 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.)

  20. 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

  1. 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.)

  2. 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

  3. 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

  4. 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.)

  5. 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.)

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2009-04-15

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

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

    Science.gov (United States)

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

    2015-01-01

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

  8. 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.

  9. 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.

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

    Energy Technology Data Exchange (ETDEWEB)

    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.)

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

    Energy Technology Data Exchange (ETDEWEB)

    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.)

  12. 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.)

  13. 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

  14. 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.)

  15. 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

  16. Magnetic resonance annual 1986

    International Nuclear Information System (INIS)

    Kressel, H.Y.

    1986-01-01

    This book contains papers written on magnetic resonance during 1986. Topics include: musculosketetal magnetic resonance imaging; imaging of the spine; magnetic resonance chemical shift imaging; magnetic resonance imaging in the central nervous system; comparison to computed tomography; high resolution magnetic resonance imaging using surface coils; magnetic resonance imaging of the chest; magnetic resonance imaging of the breast; magnetic resonance imaging of the liver; magnetic resonance spectroscopy of neoplasms; blood flow effects in magnetic resonance imaging; and current and potential applications of clinical sodium magnetic resonance imaging

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2015-11-15

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

  18. 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

  19. 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

  20. 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

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

    Energy Technology Data Exchange (ETDEWEB)

    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.

  2. 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.

  3. 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

  4. 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)

  5. 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

  6. 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.)

  7. 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.)

  8. 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 ...

  9. 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.)

  10. 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 ...

  11. MRI (Magnetic Resonance Imaging)

    Science.gov (United States)

    ... Procedures Medical Imaging MRI (Magnetic Resonance Imaging) MRI (Magnetic Resonance Imaging) Share Tweet Linkedin Pin it More sharing options Linkedin Pin it Email Print Magnetic Resonance Imaging (MRI) is a medical imaging procedure for ...

  12. Bifurcation magnetic resonance in films magnetized along hard magnetization axis

    Energy Technology Data Exchange (ETDEWEB)

    Vasilevskaya, Tatiana M., E-mail: t_vasilevs@mail.ru [Ulyanovsk State University, Leo Tolstoy 42, 432017 Ulyanovsk (Russian Federation); Sementsov, Dmitriy I.; Shutyi, Anatoliy M. [Ulyanovsk State University, Leo Tolstoy 42, 432017 Ulyanovsk (Russian Federation)

    2012-09-15

    We study low-frequency ferromagnetic resonance in a thin film magnetized along the hard magnetization axis performing an analysis of magnetization precession dynamics equations and numerical simulation. Two types of films are considered: polycrystalline uniaxial films and single-crystal films with cubic magnetic anisotropy. An additional (bifurcation) resonance initiated by the bistability, i.e. appearance of two closely spaced equilibrium magnetization states is registered. The modification of dynamic modes provoked by variation of the frequency, amplitude, and magnetic bias value of the ac field is studied. Both steady and chaotic magnetization precession modes are registered in the bifurcation resonance range. - Highlights: Black-Right-Pointing-Pointer An additional bifurcation resonance arises in a case of a thin film magnetized along HMA. Black-Right-Pointing-Pointer Bifurcation resonance occurs due to the presence of two closely spaced equilibrium magnetization states. Black-Right-Pointing-Pointer Both regular and chaotic precession modes are realized within bifurcation resonance range. Black-Right-Pointing-Pointer Appearance of dynamic bistability is typical for bifurcation resonance.

  13. Bifurcation magnetic resonance in films magnetized along hard magnetization axis

    International Nuclear Information System (INIS)

    Vasilevskaya, Tatiana M.; Sementsov, Dmitriy I.; Shutyi, Anatoliy M.

    2012-01-01

    We study low-frequency ferromagnetic resonance in a thin film magnetized along the hard magnetization axis performing an analysis of magnetization precession dynamics equations and numerical simulation. Two types of films are considered: polycrystalline uniaxial films and single-crystal films with cubic magnetic anisotropy. An additional (bifurcation) resonance initiated by the bistability, i.e. appearance of two closely spaced equilibrium magnetization states is registered. The modification of dynamic modes provoked by variation of the frequency, amplitude, and magnetic bias value of the ac field is studied. Both steady and chaotic magnetization precession modes are registered in the bifurcation resonance range. - Highlights: ► An additional bifurcation resonance arises in a case of a thin film magnetized along HMA. ► Bifurcation resonance occurs due to the presence of two closely spaced equilibrium magnetization states. ► Both regular and chaotic precession modes are realized within bifurcation resonance range. ► Appearance of dynamic bistability is typical for bifurcation resonance.

  14. 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 ...

  15. 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 ...

  16. 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 ...

  17. Arthrography

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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. ...

  18. Arthrography

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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 ...

  19. Arthrography

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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 ...

  20. Arthrography

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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 ...

  1. Arthrography

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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 ...

  2. Arthrography

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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 ...

  3. Arthrography

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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 ...

  4. Arthrography

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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 ...

  5. Arthrography

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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 ...

  6. Arthrography

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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 ...

  7. 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 ... or copied to CD. MRI does not use ionizing radiation (x-rays). CT direct arthrography uses the ...

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

    Energy Technology Data Exchange (ETDEWEB)

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

    1995-03-01

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

  9. 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

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

    Energy Technology Data Exchange (ETDEWEB)

    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.

  11. 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

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

    Energy Technology Data Exchange (ETDEWEB)

    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

  13. Nuclear magnetic resonance

    International Nuclear Information System (INIS)

    Ethier, R.; Melanson, D.; Peters, T.M.

    1983-01-01

    Ten years following computerized tomography, a new technique called nuclear magnetic resonance revolutionizes the field of diagnostic imaging. A major advantage of nuclear magnetic resonance is that the danger of radiation is non-existent as compared to computerized tomography. When parts of the human body are subject to radio-frequencies while in a fixed magnetic field, its most detailed structures are revealed. The quality of images, the applications, as well as the indications are forever increasing. Images obtained at the level of the brain and spinal cord through nuclear magnetic resonance supercede those obtained through computerized tomography. Hence, it is most likely that myelography, along with pneumoencephalography will be eliminated as a diagnostic means. It is without a doubt that nuclear magnetic resonance is tomorrow's computerized tomography [fr

  14. Arthrography

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    Full Text Available ... Videos related to Direct Arthrography Sponsored by Please note RadiologyInfo.org is not a medical facility. Please ... is further reviewed by committees from the American College of Radiology (ACR) and the Radiological Society of ...

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2014-03-15

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

  16. 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 ...

  17. 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 X-Ray and CT Exams Contrast Materials Magnetic Resonance Imaging (MRI) - Shoulder X-ray, ...

  18. Magnetic resonance imaging apparatus

    International Nuclear Information System (INIS)

    Ehnholm, G.J.

    1991-01-01

    This patent describes an electron spin resonance enhanced magnetic resonance (MR) imaging (ESREMRI) apparatus able to generate a primary magnetic field during periods of nuclear spin transition excitation and magnetic resonance signal detection. This allows the generation of ESREMRI images of a subject. A primary magnetic field of a second and higher value generated during periods of nuclear spin transition excitation and magnetic resonance signal detection can be used to generate conventional MR images of a subject. The ESREMRI and native MR images so generated may be combined, (or superimposed). (author)

  19. 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.)

  20. Diagnosis of SLAP lesions with Grashey-view arthrography

    Energy Technology Data Exchange (ETDEWEB)

    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.)

  1. Arthrography

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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 ...

  2. Arthrography

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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 ...

  3. Arthrography

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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 ...

  4. Arthrography

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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. ...

  5. 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.)

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2009-04-15

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

  7. Magnetic resonance of phase transitions

    CERN Document Server

    Owens, Frank J; Farach, Horacio A

    1979-01-01

    Magnetic Resonance of Phase Transitions shows how the effects of phase transitions are manifested in the magnetic resonance data. The book discusses the basic concepts of structural phase and magnetic resonance; various types of magnetic resonances and their underlying principles; and the radiofrequency methods of nuclear magnetic resonance. The text also describes quadrupole methods; the microwave technique of electron spin resonance; and the Mössbauer effect. Phase transitions in various systems such as fluids, liquid crystals, and crystals, including paramagnets and ferroelectrics, are also

  8. 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

  9. Arthrography

    Medline Plus

    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 ...

  10. 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.

  11. 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.

  12. Arthrography

    Medline Plus

    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 ...

  13. Magnetic resonance imaging

    International Nuclear Information System (INIS)

    Anon.

    1988-01-01

    Magnetic resonance imaging (MRI) is a new and innovative technique that affords anatomic images in multiple planes and that may provide information about tissue characterization. The magnetic resonance images are obtained by placing the patient or the area of interest within a powerful, highly uniform, static magnetic field. Magnetized protons (hydrogen nuclei) within the patient align like small magnets in this field. Radiofrequency pulses are then used to create an oscillating magnetic field perpendicular to the main field. Magnetic resonance images differ from those produced by x-rays: the latter are associated with absorption of x-ray energy while magnetic resonance images are based on proton density and proton relaxation dynamics. Proton characteristics vary according to the tissue under examination and reflect its physical and chemical properties. To resolve issues regarding safety and efficacy, the Warren Grant Magnuson Clinical Center and the Office of Medical Applications of Research of the National Institutes of Health (NIH) convened a consensus conference about MRI Oct 26 through 28, 1987. At the NIH, the Consensus Development Conference brings together investigators in the biomedical sciences, clinical investigators, practicing physicians, and consumer and special interest groups to make a scientific assessment of technologies, including drugs, devices, and procedures, and to seek agreement on their safety and effectiveness

  14. Arthrography

    Medline Plus

    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 ...

  15. Arthrography

    Medline Plus

    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 ...

  16. 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.)

  17. Pediatric magnetic resonance imaging

    International Nuclear Information System (INIS)

    Cohen, M.D.

    1986-01-01

    This book defines the current clinical potential of magnetic resonance imaging and focuses on direct clinical work with pediatric patients. A section dealing with the physics of magnetic resonance imaging provides an introduction to enable clinicians to utilize the machine and interpret the images. Magnetic resonance imaging is presented as an appropriate imaging modality for pediatric patients utilizing no radiation

  18. Advances in magnetic resonance 10

    CERN Document Server

    Waugh, John S

    2013-01-01

    Advances in Magnetic Resonance, Volume 10, presents a variety of contributions to the theory and practice of magnetic resonance. The book contains three chapters that examine superoperators in magnetic resonance; ultrasonically modulated paramagnetic resonance; and the utility of electron paramagnetic resonance (EPR) and electron-nuclear double-resonance (ENDOR) techniques for studying low-frequency modes of atomic fluctuations and their significance for understanding the mechanism of structural phase transitions in solids.

  19. 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

  20. 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

  1. Arthrography

    Medline Plus

    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 ...

  2. Children's (Pediatric) Magnetic Resonance Imaging

    Science.gov (United States)

    ... Physician Resources Professions Site Index A-Z Children’s (Pediatric) Magnetic Resonance Imaging Children’s magnetic resonance imaging (MRI) ... limitations of Children’s (Pediatric) MRI? What is Children’s (Pediatric) MRI? Magnetic resonance imaging (MRI) is a noninvasive ...

  3. Magnetic Resonance Sensors

    Directory of Open Access Journals (Sweden)

    Robert H. Morris

    2014-11-01

    Full Text Available Magnetic Resonance finds countless applications, from spectroscopy to imaging, routinely in almost all research and medical institutions across the globe. It is also becoming more frequently used for specific applications in which the whole instrument and system is designed for a dedicated application. With beginnings in borehole logging for the petro-chemical industry Magnetic Resonance sensors have been applied to fields as varied as online process monitoring for food manufacture and medical point of care diagnostics. This great diversity is seeing exciting developments in magnetic resonance sensing technology published in application specific journals where they are often not seen by the wider sensor community. It is clear that there is enormous interest in magnetic resonance sensors which represents a significant growth area. The aim of this special edition of Sensors was to address the wide distribution of relevant articles by providing a forum to disseminate cutting edge research in this field in a single open source publication.[...

  4. Magnetic Resonance Imaging (MRI) -- Head

    Science.gov (United States)

    ... News Physician Resources Professions Site Index A-Z Magnetic Resonance Imaging (MRI) - Head Magnetic resonance imaging (MRI) of the head uses a powerful ... the Head? What is MRI of the Head? Magnetic resonance imaging (MRI) is a noninvasive medical test that ...

  5. Children's (Pediatric) Magnetic Resonance Imaging

    Medline Plus

    Full Text Available ... Physician Resources Professions Site Index A-Z Children’s (Pediatric) Magnetic Resonance Imaging Children’s magnetic resonance imaging (MRI) ... limitations of Children’s (Pediatric) MRI? What is Children’s (Pediatric) MRI? Magnetic resonance imaging (MRI) is a noninvasive ...

  6. Children's (Pediatric) Magnetic Resonance Imaging

    Medline Plus

    Full Text Available ... News Physician Resources Professions Site Index A-Z Children’s (Pediatric) Magnetic Resonance Imaging Children’s magnetic resonance imaging ( ... the limitations of Children’s (Pediatric) MRI? What is Children’s (Pediatric) MRI? Magnetic resonance imaging (MRI) is a ...

  7. Arthrography

    Medline Plus

    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 ...

  8. Multidetector spiral CT arthrography of the shoulder

    Energy Technology Data Exchange (ETDEWEB)

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

    2008-10-15

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

  9. 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

  10. 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.)

  11. Magnetic resonance angiography (MRA)

    International Nuclear Information System (INIS)

    Arlart, I.P.; Guhl, L.

    1992-01-01

    An account is given in this paper of the physical and technical principles underlying the 'time-of-flight' technique for imaging of vessels by magnetic resonance tomography. Major indications for the new procedure of magnetic resonance angiography at present are intracerebral and extracerebral vessels, with digital subtraction angiography quite often being required to cope with minor alterations (small aneurysms, small occlusions). Magnetic resonance angiography and digital subtraction angiography are compared to each other for advantages and disadvantages. Basically, replacement of radiological angiography by magnetic resonance angiography appears to be possible only within limits, since X-ray diagnostics primarily provides morphological information about vessels, whereas flow dynamics is visualized by the 'time-of-flight' technique. (orig.) [de

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

    Science.gov (United States)

    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

  13. A study on usefulness of CT arthrography for the temporomandibular joint

    Energy Technology Data Exchange (ETDEWEB)

    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.

  14. Wrist arthrography

    Energy Technology Data Exchange (ETDEWEB)

    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.).

  15. Magnetic Resonance Imaging (MRI) -- Head

    Medline Plus

    Full Text Available ... News Physician Resources Professions Site Index A-Z Magnetic Resonance Imaging (MRI) - Head Magnetic resonance imaging (MRI) of the head uses a powerful ... the Head? What is MRI of the Head? Magnetic resonance imaging (MRI) is a noninvasive medical test that ...

  16. Magnetic nanoparticles in magnetic resonance imaging and diagnostics.

    Science.gov (United States)

    Rümenapp, Christine; Gleich, Bernhard; Haase, Axel

    2012-05-01

    Magnetic nanoparticles are useful as contrast agents for magnetic resonance imaging (MRI). Paramagnetic contrast agents have been used for a long time, but more recently superparamagnetic iron oxide nanoparticles (SPIOs) have been discovered to influence MRI contrast as well. In contrast to paramagnetic contrast agents, SPIOs can be functionalized and size-tailored in order to adapt to various kinds of soft tissues. Although both types of contrast agents have a inducible magnetization, their mechanisms of influence on spin-spin and spin-lattice relaxation of protons are different. A special emphasis on the basic magnetism of nanoparticles and their structures as well as on the principle of nuclear magnetic resonance is made. Examples of different contrast-enhanced magnetic resonance images are given. The potential use of magnetic nanoparticles as diagnostic tracers is explored. Additionally, SPIOs can be used in diagnostic magnetic resonance, since the spin relaxation time of water protons differs, whether magnetic nanoparticles are bound to a target or not.

  17. Magnetic resonance fingerprinting.

    Science.gov (United States)

    Ma, Dan; Gulani, Vikas; Seiberlich, Nicole; Liu, Kecheng; Sunshine, Jeffrey L; Duerk, Jeffrey L; Griswold, Mark A

    2013-03-14

    Magnetic resonance is an exceptionally powerful and versatile measurement technique. The basic structure of a magnetic resonance experiment has remained largely unchanged for almost 50 years, being mainly restricted to the qualitative probing of only a limited set of the properties that can in principle be accessed by this technique. Here we introduce an approach to data acquisition, post-processing and visualization--which we term 'magnetic resonance fingerprinting' (MRF)--that permits the simultaneous non-invasive quantification of multiple important properties of a material or tissue. MRF thus provides an alternative way to quantitatively detect and analyse complex changes that can represent physical alterations of a substance or early indicators of disease. MRF can also be used to identify the presence of a specific target material or tissue, which will increase the sensitivity, specificity and speed of a magnetic resonance study, and potentially lead to new diagnostic testing methodologies. When paired with an appropriate pattern-recognition algorithm, MRF inherently suppresses measurement errors and can thus improve measurement accuracy.

  18. Advances in magnetic resonance 6

    CERN Document Server

    Waugh, John S

    2013-01-01

    Advances in Magnetic Resonance, Volume 6 focuses on the theoretical and practical aspects of applying magnetic resonance methods to various problems in physical chemistry, emphasizing the different aspects of the exegesis of these problems. This book discusses the gas phase magnetic resonance of electronically excited molecules; techniques for observing excited electronic states; NMR studies in liquids at high pressure; and effect of pressure on self-diffusion in liquids. The nuclear magnetic resonance investigations of organic free radicals; measurement of proton coupling constants by NMR; an

  19. 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

  20. 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.)

  1. Wrist ligament injuries: value of post-arthrography computed tomography

    Energy Technology Data Exchange (ETDEWEB)

    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.)

  2. Proton magnetic resonance spectroscopy and perfusion magnetic resonance imaging in the evaluation of musculoskeletal tumors

    International Nuclear Information System (INIS)

    Costa, Flavia Martins; Setti, Marcela; Vianna, Evandro Miguelote; Domingues, Romulo Cortes; Meohas, Walter; Rezende, Jose Francisco; Gasparetto, Emerson Leandro

    2009-01-01

    Objective: To assess the role of proton magnetic resonance spectroscopy and dynamic contrast-enhanced magnetic resonance imaging in the differentiation between malignant and benign musculoskeletal tumors. Materials And Methods: Fifty-five patients with musculoskeletal tumors (27 malignant and 28 benign) were studied. The examinations were performed in a 1.5 T magnetic resonance scanner with standard protocol, and single voxel proton magnetic resonance spectroscopy with 135 msec echo time. The dynamic contrast study was performed using T1-weighted gradient-echo sequence after intravenous gadolinium injection. Time signal intensity curves and slope values were calculated. The statistical analysis was performed with the Levene's test, followed by a Student's t-test, besides the Pearson's chi-squared and Fischer's exact tests. Results: Proton magnetic resonance spectroscopy sensitivity, specificity and accuracy were, respectively, 87.5%, 92.3% and 90.9% (p < 0.0001). Statistically significant difference was observed in the slope (%/min) between benign (mean, 27.5%/min) and malignant (mean, 110.9%/min) lesions (p < 0.0001). Conclusion: The time-intensity curve and slope values using dynamic-enhanced perfusion magnetic resonance imaging in association with the presence of choline peak demonstrated by single voxel magnetic resonance spectroscopy study are useful in the differentiation between malignant and benign musculoskeletal tumors. (author)

  3. 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

  4. 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.)

  5. 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.)

  6. Magnetic resonance for wireless power transfer

    OpenAIRE

    Hui, SYR

    2016-01-01

    Magnetic resonance has been a cornerstone of nonradiative wireless power transfer (WPT) since the late 19th century. However, some researchers have the misconception that magnetic resonance for WPT was developed recently. This article traces some early work of Tesla and other researchers related to the use of magnetic resonance in WPT. Included are some examples of magnetic resonance-based WPT projects conducted by researchers in the biomedical and power electronics communities over the last ...

  7. Cardiac magnetic resonance imaging

    African Journals Online (AJOL)

    2011-03-06

    Mar 6, 2011 ... Cardiac magnetic resonance imaging. Cardiovascular magnetic resonance imaging is becoming a routine diagnostic technique. BRUCE s sPOTTiswOOdE, PhD. MRC/UCT Medical Imaging Research Unit, University of Cape Town, and Division of Radiology, Stellenbosch University. Bruce Spottiswoode ...

  8. Advances in magnetic resonance 12

    CERN Document Server

    Waugh, John S

    2013-01-01

    Advances in Magnetic Resonance, Volume 12, presents a variety of contributions to the theory and practice of magnetic resonance. The book contains six chapters and begins with a discussion of diffusion and self-diffusion measurements by nuclear magnetic resonance. This is followed by separate chapters on spin-lattice relaxation time in hydrogen isotope mixtures; the principles of optical detection of nuclear spin alignment and nuclear quadropole resonance; and the spin-1 behavior, including the relaxation of the quasi-invariants of the motion of a system of pairs of dipolar coupled spin-1/2 nu

  9. Arthrography of the ankle joint in chronic instability

    Energy Technology Data Exchange (ETDEWEB)

    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.

  10. Magnetic Resonance Force Microscopy System

    Data.gov (United States)

    Federal Laboratory Consortium — The Magnetic Resonance Force Microscopy (MRFM) system, developed by ARL, is the world's most sensitive nuclear magnetic resonance (NMR) spectroscopic analysis tool,...

  11. Magnetic resonance imaging

    International Nuclear Information System (INIS)

    Robertson, Angus

    1990-01-01

    An assessment is made of the clinical benefits of expensive diagnostic technology, such as the magnetic resonance imaging. It is concluded that to most radiologists, magnetic resonance imaging has a definite place in the diagnostic scenario, especially for demonstrating central nervous system lesions in multiple sclerosis. While it is recognized that medical and financial resources are limited, it is emphasised that the cost to society must be balanced against the patient benefit. 17 refs

  12. Advances in magnetic resonance 11

    CERN Document Server

    Waugh, John S

    2013-01-01

    Advances in Magnetic Resonance, Volume 11, presents a variety of contributions to the theory and practice of magnetic resonance. The book contains three chapters and begins with a discussion of the principles and applications of dynamic nuclear polarization, with emphasis on molecular motions and collisions, intermolecular couplings, and chemical interactions. Subsequent chapters focus on the assessment of a proposed broadband decoupling method and studies of time-domain (or Fourier transform) multiple-quantum nuclear magnetic resonance.

  13. 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.

  14. Magnetic resonance imaging: effects of magnetic field strength

    International Nuclear Information System (INIS)

    Crooks, L.E.; Arakawa, M.; Hoenninger, J.; McCarten, B.; Watts, J.; Kaufman, L.

    1984-01-01

    Magnetic resonance images of the head, abdomen, and pelvis of normal adult men were obtained using varying magnetic field strength, and measurements of T1 and T2 relaxations and of signal-to-noise (SN) ratios were determined. For any one spin echo sequence, gray/white matter contrast decreases and muscle/fat contrast increases with field. SN levels rise rapidly up to 3.0 kgauss and then change more slowly, actually dropping for muscle. The optimum field for magnetic resonance imaging depends on tissue type, body part, and imaging sequence, so that it does not have a unique value. Magnetic resonance systems that operate in the 3.0-5.0 kgauss range achieve most or all of the gains that can be achieved by higher magnetic fields

  15. 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

  16. C1-2 arthrography

    Energy Technology Data Exchange (ETDEWEB)

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

    1995-08-01

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

  17. 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.)

  18. Introduction lecture to magnetic resonance

    International Nuclear Information System (INIS)

    Conard, J.

    1980-01-01

    This lecture deals with all that is common either to electron paramagnetic resonance (E.P.R.) or to nuclear magnetic resonance (N.M.R.). It will present, in an as elementary form as possible, the main concepts used in magnetic resonance emphasizing some aspects, specific for interface science. (orig./BHO)

  19. 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.)

  20. 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

  1. Advances in magnetic resonance 9

    CERN Document Server

    Waugh, John S

    2013-01-01

    Advances in Magnetic Resonance, Volume 9 describes the magnetic resonance in split constants and dipolar relaxation. This book discusses the temperature-dependent splitting constants in the ESR spectra of organic free radicals; temperature-dependent splittings in ion pairs; and magnetic resonance induced by electrons. The electron impact excitation of atoms and molecules; intramolecular dipolar relaxation in multi-spin systems; and dipolar cross-correlation problem are also elaborated. This text likewise covers the NMR studies of molecules oriented in thermotropic liquid crystals and diffusion

  2. Arthrography in sport injuries of the knee joint

    Energy Technology Data Exchange (ETDEWEB)

    Schaefer, H

    1983-09-01

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

  3. 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.)

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2017-03-15

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

  5. 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.)

  6. Magnetic Resonance Imaging (MRI) Safety

    Science.gov (United States)

    ... News Physician Resources Professions Site Index A-Z Magnetic Resonance Imaging (MRI) Safety What is MRI and how ... What is MRI and how does it work? Magnetic resonance imaging, or MRI, is a way of obtaining ...

  7. Magnetic resonance study of maghemite-based magnetic fluid

    International Nuclear Information System (INIS)

    Figueiredo, L.C.; Lacava, B.M.; Skeff Neto, K.; Pelegrini, F.; Morais, P.C.

    2008-01-01

    This study reports on the magnetic resonance (MR) data (X-band experiment) of 10.2 nm average diameter maghemite nanoparticle in the temperature range of 100-230 K. Maghemite nanoparticles were suspended as low-pH ionic magnetic fluid containing 2.3x10 17 particles/cm 3 . The temperature dependence of both resonance linewidth and resonance field of the zero-field-cooled sample as well as the resonance field of the field-cooled sample (angular variation experiment) was analyzed using well-established methodology. Information regarding particle size, particle clusterization and surface magnetic anisotropy were obtained from the analysis of the MR data. The number of magnetic sites per particle from the MR data is in excellent agreement with the number provided by the transmission electron microscopy (TEM) data. The demagnetizing field value obtained from the MR data indicates cluster of particles containing on average 1.42 particles. The MR angular variation data suggest that magnetoelastic effect accounts for the non-linearity observed for the surface component of the magnetic anisotropy

  8. Advances in magnetic resonance 1

    CERN Document Server

    Waugh, John S

    2013-01-01

    Advances in Magnetic Resonance, Volume 1, discusses developments in various areas of magnetic resonance. The subject matter ranges from original theoretical contributions through syntheses of points of view toward series of phenomena to critical and painstaking tabulations of experimental data. The book contains six chapters and begins with a discussion of the theory of relaxation processes. This is followed by separate chapters on the development of magnetic resonance techniques for studying rate processes in chemistry and the application of these techniques to various problems; the geometri

  9. Resonant and nonresonant magnetic scattering (invited)

    International Nuclear Information System (INIS)

    McWhan, D.B.; Hastings, J.B.; Kao, C.; Siddons, D.P.

    1992-01-01

    The tunability and the polarization of synchrotron radiation open up new possibilities for the study of magnetism. Studies on magnetic materials performed at the National Synchrotron Light Source are reviewed, and they fall into four areas: structure, evolution of magnetic order, separation of L and S, and resonance effects. In the vicinity of atomic absorption edges, the Faraday effect, magnetic circular dichroism, and resonant magnetic scattering are all related resonance effects which measure the spin-polarized density of states. The production and analysis of polarized beams are discussed in the context of the study of magnetism with synchrotron radiation

  10. 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

  11. A superconducting magnet for whole-body magnetic-resonance imaging

    International Nuclear Information System (INIS)

    Kan, Hisao; Watanabe, Tsugio; Takechi, Moriaki; Ogino, Osamu; Yamada, Tadatoshi

    1986-01-01

    Magnetic-resonance imaging is a promising new clinical diagnosis system that employs magnetic resonance to generate cross-sectional images of the object under examination. A large magnet plays a critical role in this system-it must supply a high-strength magnetic field that meets rigid standards of space and time uniformity. Mitsubishi Electric has developed a superconducting magnet that not only offers excellent magnetic characteristics but also features reduced helium consumption and a horizontal service port, and permits direct mounting of a magnetic shield. (author)

  12. 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.)

  13. Magnetic Resonance Imaging (MRI) -- Head

    Medline Plus

    Full Text Available ... for Brain Tumors Radiation Therapy for Head and Neck Cancer Others : American Stroke Association National Stroke Association ... MRA) Magnetic Resonance, Functional (fMRI) - Brain Head and Neck Cancer Treatment Brain Tumor Treatment Magnetic Resonance Imaging ( ...

  14. Magnetic Resonance Imaging of Stroke

    NARCIS (Netherlands)

    Bouts, Mark. J. R. J.; Wu, O.; Dijkhuizen, R. M.

    2017-01-01

    Magnetic resonance imaging (MRI) provides a powerful (neuro)imaging modality for the diagnosis and outcome prediction after (acute) stroke. Since MRI allows noninvasive, longitudinal, and three-dimensional assessment of vessel occlusion (with magnetic resonance angiography (MRA)), tissue injury

  15. Magnetic resonance elastometry using a single-sided permanent magnet

    International Nuclear Information System (INIS)

    Tan, Carl S; Marble, Andrew E; Ono, Yuu

    2012-01-01

    In this paper, we describe a magnetic resonance method of measuring material elasticity using a single-sided magnet with a permanent static field gradient. This method encodes sample velocity in a reciprocal space using Hahn spin-echoes with variable timing. The experimental results show a strong correlation between magnetic resonance signal attenuation and elasticity when an oscillating force is applied on the sample. This relationship in turn provides us with information about the displacement velocity experienced by the sample, which is inversely proportional to Young's modulus. The proposed method shows promise in offering a portable and cost-effective magnetic resonance elastography system. (paper)

  16. Children's (Pediatric) Magnetic Resonance Imaging

    Medline Plus

    Full Text Available ... Resources Professions Site Index A-Z Children’s (Pediatric) Magnetic Resonance Imaging Children’s magnetic resonance imaging (MRI) uses ... identify and accurately characterize diseases than other imaging methods. This detail makes MRI an invaluable tool in ...

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

    Energy Technology Data Exchange (ETDEWEB)

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

    1997-07-01

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

  18. 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

  19. Tunable Magnetic Resonance in Microwave Spintronics Devices

    Science.gov (United States)

    Chen, Yunpeng; Fan, Xin; Xie, Yunsong; Zhou, Yang; Wang, Tao; Wilson, Jeffrey D.; Simons, Rainee N.; Chui, Sui-Tat; Xiao, John Q.

    2015-01-01

    Magnetic resonance is one of the key properties of magnetic materials for the application of microwave spintronics devices. The conventional method for tuning magnetic resonance is to use an electromagnet, which provides very limited tuning range. Hence, the quest for enhancing the magnetic resonance tuning range without using an electromagnet has attracted tremendous attention. In this paper, we exploit the huge exchange coupling field between magnetic interlayers, which is on the order of 4000 Oe and also the high frequency modes of coupled oscillators to enhance the tuning range. Furthermore, we demonstrate a new scheme to control the magnetic resonance frequency. Moreover, we report a shift in the magnetic resonance frequency as high as 20 GHz in CoFe based tunable microwave spintronics devices, which is 10X higher than conventional methods.

  20. Children's (Pediatric) Magnetic Resonance Imaging

    Medline Plus

    Full Text Available ... Resources Professions Site Index A-Z Children’s (Pediatric) Magnetic Resonance Imaging Children’s magnetic resonance imaging (MRI) uses a powerful ... for an MRI exam contains a metal called gadolinium . Gadolinium can be used in patients with iodine ...

  1. Children's (Pediatric) Magnetic Resonance Imaging

    Medline Plus

    Full Text Available ... work? Unlike conventional x-ray examinations and computed tomography (CT) scans, MRI does not utilize ionizing radiation. Instead, ... Angiography Magnetic Resonance, Functional (fMRI) - Brain Children's (Pediatric) CT (Computed Tomography) Magnetic Resonance Imaging (MRI) Safety Contrast Materials Children ...

  2. Fourier transform nuclear magnetic resonance

    International Nuclear Information System (INIS)

    Geick, R.

    1981-01-01

    This review starts with the basic principles of resonance phenomena in physical systems. Especially, the connection is shown between the properties of these systems and Fourier transforms. Next, we discuss the principles of nuclear magnetic resonance. Starting from the general properties of physical systems showing resonance phenomena and from the special properties of nuclear spin systems, the main part of this paper reviews pulse and Fourier methods in nuclear magnetic resonance. Among pulse methods, an introduction will be given to spin echoes, and, apart from the principle of Fourier transform nuclear magnetic resonance, an introduction to the technical problems of this method, e.g. resolution in the frequency domain, aliasing, phase and intensity errors, stationary state of the spin systems for repetitive measurements, proton decoupling, and application of Fourier methods to systems in a nonequilibrium state. The last section is devoted to special applications of Fourier methods and recent developments, e.g. measurement of relaxation times, solvent peak suppression, 'rapid scan'-method, methods for suppressing the effects of dipolar coupling in solids, two-dimensional Fourier transform nuclear magnetic resonance, and spin mapping or zeugmatography. (author)

  3. 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

  4. 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

  5. Value of arthrography after supination trauma of the ankle

    Energy Technology Data Exchange (ETDEWEB)

    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.

  6. 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.)

  7. Nuclear magnetic resonance gyroscope

    International Nuclear Information System (INIS)

    Grover, B.C.

    1984-01-01

    A nuclear magnetic resonance gyro using two nuclear magnetic resonance gases, preferably xenon 129 and xenon 131, together with two alkaline metal vapors, preferably rubidium, potassium or cesium, one of the two alkaline metal vapors being pumped by light which has the wavelength of that alkaline metal vapor, and the other alkaline vapor being illuminated by light which has the wavelength of that other alkaline vapor

  8. Magnetically coupled Fano resonance of dielectric pentamer oligomer

    International Nuclear Information System (INIS)

    Zhang, Fuli; Li, Chang; He, Xuan; Chen, Lei; Fan, Yuancheng; Zhao, Qian; Zhang, Weihong; Zhou, Ji

    2017-01-01

    We present magnetically induced Fano resonance inside a dielectric metamaterial pentamer composed of ceramic bricks. Unlike previous reports where different sizes of dielectric resonators were essential to produce Fano resonance, under external magnetic field excitation, central and outer dielectric bricks with identical sizes exhibit in-phase and out-of-phase magnetic Mie oscillations. An asymmetric line shape of Fano resonance along with enhanced group delay is observed due to the interference between the magnetic resonance of the central brick and the symmetric magnetic resonance of outer bricks. Besides, Fano resonance blueshifts with the increasing resonance of the smaller central brick. The thermal-dependent permittivity of ceramics allows Fano resonance to be reversibly tuned by 300 MHz when temperature varies by 60 °C. (paper)

  9. Advances in mechanical detection of magnetic resonance

    International Nuclear Information System (INIS)

    Kuehn, Seppe; Hickman, Steven A.; Marohn, John A.

    2008-01-01

    The invention and initial demonstration of magnetic resonance force microscopy (MRFM) in the early 1990s launched a renaissance of mechanical approaches to detecting magnetic resonance. This article reviews progress made in MRFM in the last decade, including the demonstration of scanned probe detection of magnetic resonance (electron spin resonance, ferromagnetic resonance, and nuclear magnetic resonance) and the mechanical detection of electron spin resonance from a single spin. Force and force-gradient approaches to mechanical detection are reviewed and recent related work using attonewton sensitivity cantilevers to probe minute fluctuating electric fields near surfaces is discussed. Given recent progress, pushing MRFM to single proton sensitivity remains an exciting possibility. We will survey some practical and fundamental issues that must be resolved to meet this challenge.

  10. Investigation of magnetic interactions in sulfides by means of magnetic resonance

    International Nuclear Information System (INIS)

    Veen, G. van.

    1978-01-01

    Investigations have been designed to gather more information about magnetic pair interactions in sulfides by isomorphic substitution of the magnetic ions in suitable chosen diamagnetic host lattices and measurement of electron spin resonance of coupled pairs and of electron spin resonance or electron nuclear double resonance of the hyperfine interaction due to the nuclei of diamagnetic cations. The greater part of this thesis is devoted to preliminaries of magnetic resonance interpretation and sample selection and preparation. The measurements on the magnetically diluted compounds, which are described, only have an exploratory nature. (Auth.)

  11. Magnetic resonance imaging the basics

    CERN Document Server

    Constantinides, Christakis

    2014-01-01

    Magnetic resonance imaging (MRI) is a rapidly developing field in basic applied science and clinical practice. Research efforts in this area have already been recognized with five Nobel prizes awarded to seven Nobel laureates in the past 70 years. Based on courses taught at The Johns Hopkins University, Magnetic Resonance Imaging: The Basics provides a solid introduction to this powerful technology. The book begins with a general description of the phenomenon of magnetic resonance and a brief summary of Fourier transformations in two dimensions. It examines the fundamental principles of physics for nuclear magnetic resonance (NMR) signal formation and image construction and provides a detailed explanation of the mathematical formulation of MRI. Numerous image quantitative indices are discussed, including (among others) signal, noise, signal-to-noise, contrast, and resolution. The second part of the book examines the hardware and electronics of an MRI scanner and the typical measurements and simulations of m...

  12. 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

  13. [Magnetic resonance compatibility research for coronary mental stents].

    Science.gov (United States)

    Wang, Ying; Liu, Li; Wang, Shuo; Shang, Ruyao; Wang, Chunren

    2015-01-01

    The objective of this article is to research magnetic resonance compatibility for coronary mental stents, and to evaluate the magnetic resonance compatibility based on laboratory testing results. Coronary stents magnetic resonance compatibility test includes magnetically induced displacement force test, magnetically induced torque test, radio frequency induced heating and evaluation of MR image. By magnetic displacement force and torque values, temperature, and image distortion values to determine metal coronary stent demagnetization effect. The methods can be applied to test magnetic resonance compatibility for coronary mental stents and evaluate its demagnetization effect.

  14. A Magnetic Resonance Measurement Technique for Rapidly Switched Gradient Magnetic Fields in a Magnetic Resonance Tomograph

    Directory of Open Access Journals (Sweden)

    K. Bartušek

    2003-01-01

    Full Text Available This paper describes a method for measuring of the gradient magnetic field in Nuclear Magnetic Resonance (NMR tomography, which is one of the modern medical diagnostic methods. A very important prerequisite for high quality imaging is a gradient magnetic field in the instrument with exactly defined properties. Nuclear magnetic resonance enables us to measure the pulse gradient magnetic field characteristics with high accuracy. These interesting precise methods were designed, realised, and tested at the Institute of Scientific Instruments (ISI of the Academy of Sciences of the Czech Republic. The first of them was the Instantaneous Frequency (IF method, which was developed into the Instantaneous Frequency of Spin Echo (IFSE and the Instantaneous Frequency of Spin Echo Series (IFSES methods. The above named methods are described in this paper and their a comparison is also presented.

  15. The nuclear magnetic resonance well logging

    International Nuclear Information System (INIS)

    Zhang Yumin; Shen Huitang

    2003-01-01

    In this paper, the characteristic of the nuclear magnetic resonance logging is described at first. Then its development and its principle is presented. Compared with the nuclear magnetic resonance spectrometer, the magnet techniques is the first question that we must solve in the manufacture of the NMR well logging

  16. 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.)

  17. Advances in magnetic and optical resonance

    CERN Document Server

    Warren, Warren S

    1997-01-01

    Since 1965, Advances in Magnetic and Optical Resonance has provided researchers with timely expositions of fundamental new developments in the theory of, experimentation with, and application of magnetic and optical resonance.

  18. Embroidered Coils for Magnetic Resonance Sensors

    Directory of Open Access Journals (Sweden)

    Michael I. Newton

    2013-04-01

    Full Text Available Magnetic resonance imaging is a widely used technique for medical and materials imaging. Even though the objects being imaged are often irregularly shaped, suitable coils permitting the measurement of the radio-frequency signal in these systems are usually made of solid copper. One problem often encountered is how to ensure the coils are both in close proximity and conformal to the object being imaged. Whilst embroidered conductive threads have previously been used as antennae in mobile telecommunications applications, they have not previously been reported for use within magnetic resonance. In this paper we show that an embroidered single loop coil can be used in a commercial unilateral nuclear magnetic resonance system as an alternative to a solid copper. Data is presented showing the determination of both longitudinal (T1 and effective transverse (T2eff relaxation times for a flat fabric coil and the same coil conformed to an 8 cm diameter cylinder. We thereby demonstrate the principles required for the wider use of fabric based conformal coils within nuclear magnetic resonance and magnetic resonance imaging.

  19. 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

  20. Nuclear magnetic resonance imaging

    International Nuclear Information System (INIS)

    Young, I.R.

    1984-01-01

    In a method of imaging a body in which nuclear magnetic resonance is excited in a region including part of the body, and the free induction decay signal is measured, a known quantity of a material of known nuclear magnetic resonance properties, for example a bag of water, is included in the region so as to enhance the measured free induction decay signal. This then reduces the generation of noise during subsequent processing of the signal. (author)

  1. Nuclear magnetic resonance diagnostic apparatus

    International Nuclear Information System (INIS)

    Sugimoto, H.

    1985-01-01

    Nuclear magnetic resonance diagnostic apparatus including a coil for generating a gradient field in a plane perpendicular to a static magnetic field, means for controlling the operation of the coil to rotationally shift in angular steps the gradient direction of the gradient field at an angle pitch of some multiple of the unit index angle through a plurality of rotations to assume all the shift positions of the gradient direction, a rough image reconstructor for reconstructing a rough tomographic image on the basis of nuclear magnetic resonance signals acquired during a rotation of the second gradient magnetic field, a rough image display for depicting the rough tomographic image, a final image reconstructor for reconstructing a final tomographic image on the basis of all nuclear magnetic resonance signals corresponding to all of the expected rotation shift positions acquired during a plurality of rotations and a final image display for depicting the final tomographic image

  2. Nuclear magnetic resonance apparatus

    International Nuclear Information System (INIS)

    Lambert, R.

    1991-01-01

    In order to include the effect of a magnetic object in a subject under investigation, Nuclear Magnetic Resonance (NMR) apparatus is operable at more than one radio frequency (RF) frequency. The apparatus allows normal practice as far as obtaining an NMR response or image from a given nuclear species is concerned, but, in addition, interrogates the nuclear spin system at a frequency which is different from the resonance frequency normally used for the given nuclear species, as determined from the applied magnetic field. The magnetic field close to a magnetised or magnetisable object is modified and the given nuclear species gives a response at the different frequency. Thus detection of a signal at the frequency indicates the presence of the chosen nuclei close to the magnetised or magnetisable object. Applications include validation of an object detection or automatic shape inspection system in the presence of magnetic impurities, and the detection of magnetic particles which affect measurement of liquid flow in a pipe. (author)

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

    Energy Technology Data Exchange (ETDEWEB)

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

    1992-11-15

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

  4. 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

  5. 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

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

    Energy Technology Data Exchange (ETDEWEB)

    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.

  7. 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.)

  8. 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

  9. Magnetic resonance and porous materials

    International Nuclear Information System (INIS)

    McDonald, P.; Strange, J.

    1998-01-01

    Mention the words magnetic resonance to your medical advisor and he or she will immediately think of a multi-million pound scanner that peers deep into the brain. A chemist, on the other hand, will imagine a machine that costs several hundred thousand pounds and produces high-resolution spectra for chemical analysis. Food technologists will probably think of a bench-top instrument for determining moisture content, while an oil prospector will envisage a device that can be operated several kilometres down an oil well. To a physicist the term is more likely to conjure up a mental picture of nuclear spins precessing in a magnetic field. These examples illustrate the diverse aspects of a phenomenon discovered by physicists over 50 years ago. Electron spin resonance was first discovered by Russian scientists, and nuclear magnetic resonance was discovered in the US shortly afterwards by Ed Purcell at Harvard University and Felix Bloch at Stanford University. Today, nuclear magnetic resonance (NMR) is the most widely used technique. Modern NMR machines are making it possible to probe microstructure and molecular movement in materials as diverse as polymers, cements, rocks, soil and foods. NMR allows the distribution of different components in a material to be determined with a resolution approaching 1μm, although the signal can be sensitive to even smaller lengthscales. In this article the authors describe how physicists are still developing magnetic resonance to exploit a range of new applications. (UK)

  10. 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.

  11. Magnetic resonance imaging by using nano-magnetic particles

    Energy Technology Data Exchange (ETDEWEB)

    Shokrollahi, H., E-mail: Shokrollahi@sutech.ac.ir [Electroceramics Group, Department of Materials Science and Engineering, Shiraz University of Technology, Shiraz (Iran, Islamic Republic of); Khorramdin, A. [Electroceramics Group, Department of Materials Science and Engineering, Shiraz University of Technology, Shiraz (Iran, Islamic Republic of); Isapour, Gh. [Department of Materials and Engineering, Hakim Sabzevari University (Iran, Islamic Republic of)

    2014-11-15

    Magnetism and magnetic materials play a major role in various biological applications, such as magnetic bioseparation, magnetic resonance imaging (MRI), hyperthermia treatment of cancer and drug delivery. Among these techniques, MRI is a powerful method not only for diagnostic radiology but also for therapeutic medicine that utilizes a magnetic field and radio waves. Recently, this technique has contributed greatly to the promotion of the human quality life. Thus, this paper presents a short review of the physical principles and recent advances of MRI, as well as providing a summary of the synthesis methods and properties of contrast agents, like different core materials and surfactants. - Highlights: • This paper studies the physics of MRI as a powerful diagnostic technique. • MRI uses the differentiation between healthy and pathological tissues. • The relaxation times can be shortened by the use of a magnetic contrast agent. • The magnetic nanoparticles act as contrast agents, helping to increase the resolution. • Different synthesis methods can influence the magnetic resonance behavior.

  12. Magnetic resonance imaging of the prostate

    DEFF Research Database (Denmark)

    Iversen, P; Kjaer, L; Thomsen, C

    1988-01-01

    Magnetic resonance imaging offers new possibilities in investigation of the prostate gland. Current results of imaging and tissue discrimination in the evaluation of prostatic disease are reviewed. Magnetic resonance imaging may be useful in the staging of carcinoma of the prostate....

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

    Energy Technology Data Exchange (ETDEWEB)

    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.)

  14. 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.)

  15. 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

  16. 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

  17. Magnetic resonance imaging of the prostate

    DEFF Research Database (Denmark)

    Iversen, P; Kjaer, L; Thomsen, C

    1987-01-01

    Magnetic resonance imaging offers new possibilities in the investigation of the prostate. The current results of imaging and tissue discrimination in the evaluation of prostatic disease are reviewed. Magnetic resonance imaging may be of value in the staging of carcinoma of the prostate....

  18. Magnetic resonance of low dimensional magnetic solids

    Energy Technology Data Exchange (ETDEWEB)

    Gatteschi, D.; Ferraro, F.; Sessoli, R. (Florence Univ. (Italy))

    1994-06-01

    The utility of EPR and NMR in the study of low-dimensional magnetic solids is shown. A short summary of the basis of magnetic resonance in these systems is reported, and the importance of spin-diffusion and magnetic anisotropy evidenced. Some results from experiments on metal-radical chains and clusters are presented. (authors). 37 refs., 7 figs.

  19. Magnetic resonance of low dimensional magnetic solids

    International Nuclear Information System (INIS)

    Gatteschi, D.; Ferraro, F.; Sessoli, R.

    1994-01-01

    The utility of EPR and NMR in the study of low-dimensional magnetic solids is shown. A short summary of the basis of magnetic resonance in these systems is reported, and the importance of spin-diffusion and magnetic anisotropy evidenced. Some results from experiments on metal-radical chains and clusters are presented. (authors). 37 refs., 7 figs

  20. Diagnosis of triangular fibrocartilage complex injury using arthrography and MRI

    Energy Technology Data Exchange (ETDEWEB)

    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)

  1. 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.)

  2. The nuclear magnetic resonance spectroscopy

    International Nuclear Information System (INIS)

    Goyer, Ph.

    1997-01-01

    The spectroscopy of nuclear magnetic resonance constitutes a major analytical technique in biological and organic analysis. This technique appears now in the programme of preparatory classes and its teaching is developed in the second year of DEUG. The following article reviews on the nuclear magnetic resonance and on the possibilities it offers to bring to the fore the physico-chemical properties of molecules. (N.C.)

  3. Advances in magnetic resonance 2

    CERN Document Server

    Waugh, John S

    2013-01-01

    Advances in Magnetic Resonance, Volume 2, features a mixture of experimental and theoretical contributions. The book contains four chapters and begins with an ambitious and general treatment of the problem of signal-to-noise ratio in magnetic resonance. This is followed by separate chapters on the interpretation of nuclear relaxation in fluids, with special reference to hydrogen; and various aspects of molecular theory of importance in NMR.

  4. Magnetic resonance annual, 1988

    International Nuclear Information System (INIS)

    Kressel, H.Y.

    1987-01-01

    This book features reviews of high-resolution MRI of the knee, MRI of the normal and ischmeic hip, MRI of the heart, and temporomandibular joint imaging, as well as thorough discussion on artifacts in magnetic resonance imaging. Contributors consider the clinical applications of gadolinium-DTPA in magnetic resonance imaging and the clinical use of partial saturation and saturation recovery sequences. Timely reports assess the current status of rapid MRI and describe a new rapid gated cine MRI technique. Also included is an analysis of cerebrospinal fluid flow effects during MRI of the central nervous system

  5. Magnetic resonance angiography

    Science.gov (United States)

    ... Saunders; 2015:chap 17. Litt H, Carpenter JP. Magnetic resonance imaging. In: Cronenwett JL, Johnston KW, eds. Rutherford's Vascular Surgery . 8th ed. Philadelphia, PA: Elsevier Saunders; 2014:chap ...

  6. Children's (Pediatric) Magnetic Resonance Imaging

    Medline Plus

    Full Text Available ... magnetic resonance imaging (MRI) uses a powerful magnetic field, radio waves and a computer to produce detailed ... problems, medications, recent surgeries and allergies. The magnetic field is not harmful, but it may cause some ...

  7. 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.)

  8. Magnetic resonance imaging: hazard, risk and safety

    International Nuclear Information System (INIS)

    Narayan, Pradeep; Suri, S.; Singh, P.

    2001-01-01

    The hazard and risk associated with magnetic resonance imaging is a matter of concern. In 1982, the Food and Drug Administration (FDA), USA issued guidelines to Hospital's Investigational Review Board (IRBs) in 'Guidelines for Evaluating Electromagnetic Exposure Risks for Trials of Clinical Nuclear Magnetic Resonance (NMR)'. In 1997, the Berufsgenossenschaft (BG), professional association for precision engineering and electronics of Germany, in their preliminary proposal for safety limits extended their concerns on static magnetic field. Owing to both time varying and static magnetic fields applied in Magnetic Resonance Imaging (MRI) this became of immediate concern to user community to assess the potential hazard and risk associated with the NMR system

  9. Magnetic resonance phenomena in dynamics of relativistic particles

    International Nuclear Information System (INIS)

    Ternov, I.M.; Bordovitsyn, V.A.

    1987-01-01

    A relativistic generalization of Rabi's formula for magnetic resonance is given. On this basis, we consider fast and slow passage through resonance. We define a magnetic resonance exterior field as usual, using unit vectors of a Cartesian coordinate system, a homogeneous magnetic field, and the amplitude of a rotating magnetic field. For the description of spin dynamics we use the Bargmann-Michel-Telegdi equation

  10. Magnetic resonance imaging in sudden deafness

    International Nuclear Information System (INIS)

    Ramos, Hugo Valter Lisboa; Barros, Flavia Alencar; Penido, Norma de Oliveira; Souza, Ana Claudia Valerio de; Yamaoka, Wellington Yugo; Yamashita, Helio

    2005-01-01

    The etiology of sudden deafness can remain undetermined despite extensive investigation. This study addresses the value of magnetic resonance imaging in the analysis of sudden deafness patients.Study Design: transversal cohort.Material And Method: In a prospective study, 49 patients attended at otolaryngology emergency room of Federal University of Sao Paulo - Escola Paulista de Medicina, from April 2001 to May 2003, were submitted to magnetic resonance imaging.Results: Magnetic Resonance abnormalities were seen in 23 (46.9%) patients and revealed two tumors suggestive of meningioma, three vestibular schwannomas, thirteen microangiopathic changes of the brain and five (21.7%) pathological conditions of the labyrinth.Conclusion: Sudden deafness should be approached as a symptom common to different diseases. The presence of cerebellopontine angle tumors in 10.2% of our cases, among other treatable causes, justifies the recommendation of gadolinium-enhanced magnetic resonance use, not only to study the auditory peripheral pathway, but to study the whole auditory pathway including the brain. (author)

  11. Magnetic Resonance Imaging (MRI): Brain (For Parents)

    Science.gov (United States)

    ... Staying Safe Videos for Educators Search English Español Magnetic Resonance Imaging (MRI): Brain KidsHealth / For Parents / Magnetic Resonance Imaging (MRI): Brain What's in this article? What ...

  12. Magnetic resonance signal moment determination using the Earth's magnetic field

    KAUST Repository

    Fridjonsson, Einar Orn; Creber, Sarah A.; Vrouwenvelder, Johannes S.; Johns, Michael L.

    2015-01-01

    We demonstrate a method to manipulate magnetic resonance data such that the moments of the signal spatial distribution are readily accessible. Usually, magnetic resonance imaging relies on data acquired in so-called k-space which is subsequently Fourier transformed to render an image. Here, via analysis of the complex signal in the vicinity of the centre of k-space we are able to access the first three moments of the signal spatial distribution, ultimately in multiple directions. This is demonstrated for biofouling of a reverse osmosis (RO) membrane module, rendering unique information and an early warning of the onset of fouling. The analysis is particularly applicable for the use of mobile magnetic resonance spectrometers; here we demonstrate it using an Earth's magnetic field system.

  13. Magnetic resonance signal moment determination using the Earth's magnetic field

    KAUST Repository

    Fridjonsson, Einar Orn

    2015-03-01

    We demonstrate a method to manipulate magnetic resonance data such that the moments of the signal spatial distribution are readily accessible. Usually, magnetic resonance imaging relies on data acquired in so-called k-space which is subsequently Fourier transformed to render an image. Here, via analysis of the complex signal in the vicinity of the centre of k-space we are able to access the first three moments of the signal spatial distribution, ultimately in multiple directions. This is demonstrated for biofouling of a reverse osmosis (RO) membrane module, rendering unique information and an early warning of the onset of fouling. The analysis is particularly applicable for the use of mobile magnetic resonance spectrometers; here we demonstrate it using an Earth\\'s magnetic field system.

  14. Magnetic Resonance Imaging. Chapter 15

    Energy Technology Data Exchange (ETDEWEB)

    Leach, M. O. [The Institute of Cancer Research and The Royal Marsden Hospital, London (United Kingdom)

    2014-09-15

    In Chapter 14, the principles of nuclear magnetic resonance were presented, along with an introduction to image forming processes. In this chapter, magnetic resonance imaging (MRI) will be reviewed, beginning with the hardware needed and its impact on image quality. The acquisition processes and image reconstruction will be discussed, as well as the artefacts that are possible, with discussion of the important area of safety and bioeffects completing the chapter.

  15. 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

  16. Force detection of nuclear magnetic resonance

    International Nuclear Information System (INIS)

    Rugar, D.; Zueger, O.; Hoen, S.; Yannoni, C.S.; Vieth, H.M.; Kendrick, R.D.

    1994-01-01

    Micromechanical sensing of magnetic force was used to detect nuclear magnetic resonance with exceptional sensitivity and spatial resolution. With a 900 angstrom thick silicon nitride cantilever capable of detecting subfemtonewton forces, a single shot sensitivity of 1.6 x 10 13 protons was achieved for an ammonium nitrate sample mounted on the cantilever. A nearby millimeter-size iron particle produced a 600 tesla per meter magnetic field gradient, resulting in a spatial resolution of 2.6 micrometers in one dimension. These results suggest that magnetic force sensing is a viable approach for enhancing the sensitivity and spatial resolution of nuclear magnetic resonance microimaging

  17. Arthrography

    Medline Plus

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

  18. Principles of magnetic resonance imaging

    International Nuclear Information System (INIS)

    Mlynarik, V.; Tkac, I.; Srbecky, M.

    1995-01-01

    The aim of this review is to describe and explain the basic principles of magnetic resonance imaging. The first part of the text is devoted to the phenomenon of magnetic resonance (the interaction of RF magnetic field with the set of magnetic moments in the homogeneous magnetic field) and to relaxation processes. Then, the creation of MR image is described (slice selection, phase and frequency encoding of spatial information). The basic and the most frequently used techniques are explained (spin echo, gradient echo). The way the repetition and echo times influence the image quality and contrast (T1 or T2 weighing) is described. The part with the technical description of the MR equipment is included in the review. The MR imagination examination are compared with X-ray computer tomography technique

  19. Magnetic resonance imaging in clinically-definite multiple sclerosis

    International Nuclear Information System (INIS)

    Noakes, J.B.; Herkes, G.K.; Frith, J.A.

    1990-01-01

    Forty-two patients with clinically-definite multiple sclerosis were examined by magnetic resonance imaging using a 1.5-T instrument. Magnetic resonance imaging detected an abnormality in 90% of patients. In four patients, no lesions were demonstrated. The number, size and site of the lesions by magnetic resonance imaging were compared with the patients' clinical status and other variables. The Kurtzke disability status scale score increased in patients with corpus callosum atrophy, brainstem and basal ganglia lesions, and correlated with the total number of lesions. No correlation was shown between the findings of magnetic resonance imaging and disease duration, age, sex or pattern-reversal visual-evoked potentials. The variety of magnetic resonance images that could be obtained in patients with clinically-definite multiple sclerosis is highlighted. 24 refs., 8 figs., 1 tab

  20. A Simple Technique for Shoulder Arthrography

    Energy Technology Data Exchange (ETDEWEB)

    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.

  1. Nuclear magnetic resonance method and apparatus

    International Nuclear Information System (INIS)

    Burl, M.; Young, I.R.

    1984-01-01

    A method and apparatus for determining the rate of flow of a liquid in a selected region of a body by nuclear magnetic resonance techniques are described. The method includes a sequence of applying a first magnetic pulse effective to excite nuclear magnetic resonance of a chosen nucleus within the liquid preferentially in a slice of the body which includes the selected region. A period of time (tsub(D)) is waited and then a second magnetic pulse is applied which is effective to excite nuclear magnetic resonance of the nuclei preferentially in the slice, and the free induction decay signal is measured. The whole sequence is repeated for different values of the period of time (tsub(D)). The variation in the value of the measured signal with tsub(D) is then related to the rate of flow of the liquid through the slice. (author)

  2. Arthrography

    Medline Plus

    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 | ...

  3. Arthrography

    Medline Plus

    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 ...

  4. Arthrography

    Medline Plus

    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 ...

  5. Interaction of magnetic resonators studied by the magnetic field enhancement

    Directory of Open Access Journals (Sweden)

    Yumin Hou

    2013-12-01

    Full Text Available It is the first time that the magnetic field enhancement (MFE is used to study the interaction of magnetic resonators (MRs, which is more sensitive than previous parameters–shift and damping of resonance frequency. To avoid the coherence of lattice and the effect of Bloch wave, the interaction is simulated between two MRs with same primary phase when the distance is changed in the range of several resonance wavelengths, which is also compared with periodic structure. The calculated MFE oscillating and decaying with distance with the period equal to resonance wavelength directly shows the retardation effect. Simulation also shows that the interaction at normal incidence is sensitive to the phase correlation which is related with retardation effect and is ultra-long-distance interaction when the two MRs are strongly localized. When the distance is very short, the amplitude of magnetic resonance is oppressed by the strong interaction and thus the MFE can be much lower than that of single MR. This study provides the design rules of metamaterials for engineering resonant properties of MRs.

  6. Nuclear Magnetic Resonance Spectroscopy

    Indian Academy of Sciences (India)

    Home; Journals; Resonance – Journal of Science Education; Volume 9; Issue 1. Nuclear Magnetic Resonance Spectroscopy. Susanta Das. General Article Volume 9 Issue 1 January 2004 pp 34-49. Fulltext. Click here to view fulltext PDF. Permanent link: https://www.ias.ac.in/article/fulltext/reso/009/01/0034-0049. Keywords.

  7. Magnetic resonance imaging of the fetal brain.

    Science.gov (United States)

    Tee, L Mf; Kan, E Yl; Cheung, J Cy; Leung, W C

    2016-06-01

    This review covers the recent literature on fetal brain magnetic resonance imaging, with emphasis on techniques, advances, common indications, and safety. We conducted a search of MEDLINE for articles published after 2010. The search terms used were "(fetal OR foetal OR fetus OR foetus) AND (MR OR MRI OR [magnetic resonance]) AND (brain OR cerebral)". Consensus statements from major authorities were also included. As a result, 44 relevant articles were included and formed the basis of this review. One major challenge is fetal motion that is largely overcome by ultra-fast sequences. Currently, single-shot fast spin-echo T2-weighted imaging remains the mainstay for motion resistance and anatomical delineation. Recently, a snap-shot inversion recovery sequence has enabled robust T1-weighted images to be obtained, which is previously a challenge for standard gradient-echo acquisitions. Fetal diffusion-weighted imaging, diffusion tensor imaging, and magnetic resonance spectroscopy are also being developed. With multiplanar capabilities, superior contrast resolution and field of view, magnetic resonance imaging does not have the limitations of sonography, and can provide additional important information. Common indications include ventriculomegaly, callosum and posterior fossa abnormalities, and twin complications. There are safety concerns about magnetic resonance-induced heating and acoustic damage but current literature showed no conclusive evidence of deleterious fetal effects. The American College of Radiology guideline states that pregnant patients can be accepted to undergo magnetic resonance imaging at any stage of pregnancy if risk-benefit ratio to patients warrants that the study be performed. Magnetic resonance imaging of the fetal brain is a safe and powerful adjunct to sonography in prenatal diagnosis. It can provide additional information that aids clinical management, prognostication, and counselling.

  8. Arthrography

    Medline Plus

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

  9. NMR magnetic field controller for pulsed nuclear magnetic resonance experiments

    International Nuclear Information System (INIS)

    Scheler, G.; Anacker, M.

    1975-01-01

    A nuclear magnetic resonance controller for magnetic fields, which can also be used for pulsed NMR investigations, is described. A longtime stability of 10 -7 is achieved. The control signal is generated by a modified time sharing circuit with resonance at the first side band of the 2 H signal. An exact calibration of the magnetic field is achieved by the variation of the H 1 - or of the time-sharing frequency. (author)

  10. Resonance of magnetization excited by voltage in magnetoelectric heterostructures

    Science.gov (United States)

    Yu, Guoliang; Zhang, Huaiwu; Li, Yuanxun; Li, Jie; Zhang, Dainan; Sun, Nian

    2018-04-01

    Manipulation of magnetization dynamics is critical for spin-based devices. Voltage driven magnetization resonance is promising for realizing low-power information processing systems. Here, we show through Finite Element Method (FEM) simulations that magnetization resonance in nanoscale magnetic elements can be generated by a radio frequency (rf) voltage via the converse magnetoelectric (ME) effect. The magnetization dynamics induced by voltage in a ME heterostructures is simulated by taking into account the magnetoelastic and piezoelectric coupling mechanisms among magnetization, strain and voltage. The frequency of the excited magnetization resonance is equal to the driving rf voltage frequency. The proposed voltage driven magnetization resonance excitation mechanism opens a way toward energy-efficient spin based device applications.

  11. 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

  12. 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

  13. Waveguide volume probe for magnetic resonance imaging and spectroscopy

    DEFF Research Database (Denmark)

    2015-01-01

    The present disclosure relates to a probe for use within the field of nuclear magnetic resonance, such as magnetic resonance imaging (MRI), and magnetic resonance spectroscopy (MRS)). One embodiment relates to an RF probe for magnetic resonance imaging and/or spectroscopy comprising a conductive...... non-magnetic hollow waveguide having an internal volume and at least one open end, one or more capacitors and at least a first conductive non-magnetic wire, wherein said first conductive wire connects at least one of said one or more capacitors to opposite walls of one open end of the waveguide...

  14. 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.

  15. Observation of ferromagnetic resonance in a microscopic sample using magnetic resonance force microscopy

    International Nuclear Information System (INIS)

    Zhang, Z.; Hammel, P.C.; Wigen, P.E.

    1996-01-01

    We report the observation of a ferromagnetic resonance signal arising from a microscopic (∼20μmx40μm) particle of thin (3μm) yttrium iron garnet film using magnetic resonance force microscopy (MRFM). The large signal intensity in the resonance spectra suggests that MRFM could become a powerful microscopic ferromagnetic resonance technique with a micron or sub-micron resolution. We also observe a very strong nonresonance signal which occurs in the field regime where the sample magnetization readily reorients in response to the modulation of the magnetic field. This signal will be the main noise source in applications where a magnet is mounted on the cantilever. copyright 1996 American Institute of Physics

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2012-08-15

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

  17. The particle concentration effect on magnetic resonance linewidth for magnetic liquids with chain aggregates

    International Nuclear Information System (INIS)

    Marin, C.N.

    2002-01-01

    Based on the assumption of particle chains formation within a magnetic liquid, computer simulation of the magnetic resonance line is presented. The dependence on particle concentration within a magnetic liquid of magnetic resonance linewidth is analyzed. The computer simulation demonstrates that the particles chaining has an important effect on the enlargement of the magnetic resonance line. Increasing the particle concentration within magnetic liquid leads to an increase in the linewidth. The agreement with some experimental findings is discussed

  18. Improved identification of the palmar fibrocartilage of the navicular bone with saline magnetic resonance bursography.

    Science.gov (United States)

    Schramme, Michael; Kerekes, Zoltan; Hunter, Stuart; Nagy, Krisztina; Pease, Anthony

    2009-01-01

    Fibrocartilage degeneration is the earliest pathologic finding in navicular disease but remains difficult to detect, even with magnetic resonance (MR) imaging. We hypothesized that injection of the navicular bursa with saline would improve accuracy of MR imaging evaluation of palmar fibrocartilage. Thoracic limbs were collected from 11 horses within 6 h of death. Imaging was performed with a 1.5 T magnet using sagittal 2D proton density and transverse 3D FLASH sequences with fat saturation. For the purpose of determining sensitivity and specificity of the MR images, fibrocartilage was classified as normal or abnormal, based on combination of the findings of gross and microscopic pathology. Thickness of fibrocartilage was measured on histologic sections and corresponding transverse FLASH MR images before and after injection of saline. A paired Student's t-test was used for comparison of measurements. Partial thickness fibrocartilage loss was present in 6 of 22 limbs. Sensitivity of precontrast MR images for detection of lesions was 100% while specificity was 6%. Saline MR arthrography resulted in both sensitivity and specificity of 100% based on consensus review. Mean histologic fibrocartilage thickness was 0.75 +/- 0.12 mm. Mean fibrocartilage thickness on precontrast transverse FLASH images was 0.93 +/- 0.065 and 0.73 +/- 0.09 mm on postsaline images. The histologic cartilage thickness was signficantly different from that in precontrast images (Pfibrocartilage can only be evaluated reliably for the presence of partial thickness lesions after intrabursal injection of saline.

  19. 76 FR 58281 - Magnetic Resonance Imaging Safety; Public Workshop

    Science.gov (United States)

    2011-09-20

    ...] Magnetic Resonance Imaging Safety; Public Workshop AGENCY: Food and Drug Administration, HHS. ACTION... announcing a public workshop entitled: ``Magnetic Resonance Imaging (MRI) Safety Public Workshop.'' The purpose of the public workshop is to discuss factors affecting the safe use of magnetic resonance imaging...

  20. Functional magnetic resonance imaging of the primary motor cortex ...

    Indian Academy of Sciences (India)

    Unknown

    Abbreviations used: BOLD, Blood oxygenation level dependent; CBF, cerebral blood flow; fMRI, functional magnetic resonance imaging; EPI, eco-planar imaging; FOV, field of view; MRI, Magnetic resonance imaging; MRS, magnetic resonance spectroscopy;. PET, position emission tomography; rCBF, regional cerebral ...

  1. 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

  2. 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

  3. Magnetic resonance angiography for the head and neck region

    International Nuclear Information System (INIS)

    Aschenbach, R.; Esser, D.

    2004-01-01

    Magnetic resonance angiography is a noninvasive method in vascular imaging using noncontrast- enhanced and contrast-enhanced techniques. The contrast media used in contrast- enhanced magnetic resonance angiography are different from the X-ray contrast media and do not affect the thyroid gland or renal function. In detecting hypervascularized lesions in the head and neck, contrast-enhanced magnetic resonance angiography is the method of choice, which provides an acceptable quality in comparison to digital subtraction angiography. Future developments in magnetic resonance imaging techniques will cause a wider use of magnetic resonance angiography, especially in head and neck imaging. Digital subtraction angiography should therefore only be used in problem cases and for preoperative embolization [de

  4. Single voxel magnetic resonance spectroscopy in distinguishing ...

    African Journals Online (AJOL)

    Objective: Assess diagnostic utility of combined magnetic resonance imaging and magnetic resonance spectroscopy (MRI, MRS) in differentiating focal neoplastic lesions from focal non- neoplastic (infective or degenerative) brain lesions. Design: Descriptive, analytical - prospective study. Setting: The Aga Khan University ...

  5. Your Radiologist Explains Magnetic Resonance Angiography (MRA)

    Medline Plus

    Full Text Available ... Sponsored by Image/Video Gallery Your Radiologist Explains Magnetic Resonance Angiography (MRA) Transcript Welcome to Radiology Info dot ... I’d like to talk with you about magnetic resonance angiography, or as it’s commonly known, MRA. MRA ...

  6. 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

  7. Contrast agents in magnetic resonance imaging

    International Nuclear Information System (INIS)

    Karadjian, V.

    1987-01-01

    The origine of nuclear magnetic resonance signal is reminded and different ways for contrast enhancement in magnetic resonance imaging are presented, especially, modifications of tissus relaxation times. Investigations have focused on development of agents incorporating either paramagnetic ions or stable free radicals. Pharmacological and toxicological aspects are developed. The diagnostic potential of these substances is illustrated by the example of gadolinium complexes [fr

  8. Magnetic resonance: discovery, investigations, and applications

    International Nuclear Information System (INIS)

    Kessenikh, Aleksandr V

    2009-01-01

    The history of the development of the theoretical ideas and experimental methods of magnetic resonance, as well as the applications of these methods in modern natural science, technology, and medicine, are outlined, with allowance for the contribution of Russian researchers. An assessment of some promising trends of studies and applications of magnetic resonance is given. (from the history of physics)

  9. Reducing Field Distortion in Magnetic Resonance Imaging

    Science.gov (United States)

    Eom, Byeong Ho; Penanen, Konstantin; Hahn, Inseob

    2010-01-01

    A concept for a magnetic resonance imaging (MRI) system that would utilize a relatively weak magnetic field provides for several design features that differ significantly from the corresponding features of conventional MRI systems. Notable among these features are a magnetic-field configuration that reduces (relative to the conventional configuration) distortion and blurring of the image, the use of a superconducting quantum interference device (SQUID) magnetometer as the detector, and an imaging procedure suited for the unconventional field configuration and sensor. In a typical application of MRI, a radio-frequency pulse is used to excite precession of the magnetic moments of protons in an applied magnetic field, and the decaying precession is detected for a short time following the pulse. The precession occurs at a resonance frequency proportional to the strengths of the magnetic field and the proton magnetic moment. The magnetic field is configured to vary with position in a known way; hence, by virtue of the aforesaid proportionality, the resonance frequency varies with position in a known way. In other words, position is encoded as resonance frequency. MRI using magnetic fields weaker than those of conventional MRI offers several advantages, including cheaper and smaller equipment, greater compatibility with metallic objects, and higher image quality because of low susceptibility distortion and enhanced spin-lattice-relaxation- time contrast. SQUID MRI is being developed into a practical MRI method for applied magnetic flux densities of the order of only 100 T

  10. Pulse sequences for contrast-enhanced magnetic resonance imaging

    International Nuclear Information System (INIS)

    Graves, Martin J.

    2007-01-01

    The theory and application of magnetic resonance imaging (MRI) pulse sequences following the administration of an exogenous contrast agent are discussed. Pulse sequences are categorised according to the contrast agent mechanism: changes in proton density, relaxivity, magnetic susceptibility and resonant frequency shift. Applications in morphological imaging, magnetic resonance angiography, dynamic imaging and cell labelling are described. The importance of optimising the pulse sequence for each application is emphasised

  11. Magnetic field induced incommensurate resonance in cuprate superconductors

    International Nuclear Information System (INIS)

    Zhang Jingge; Cheng Li; Guo Huaiming; Feng Shiping

    2009-01-01

    The influence of a uniform external magnetic field on the dynamical spin response of cuprate superconductors in the superconducting state is studied based on the kinetic energy driven superconducting mechanism. It is shown that the magnetic scattering around low and intermediate energies is dramatically changed with a modest external magnetic field. With increasing the external magnetic field, although the incommensurate magnetic scattering from both low and high energies is rather robust, the commensurate magnetic resonance scattering peak is broadened. The part of the spin excitation dispersion seems to be an hourglass-like dispersion, which breaks down at the heavily low energy regime. The theory also predicts that the commensurate resonance scattering at zero external magnetic field is induced into the incommensurate resonance scattering by applying an external magnetic field large enough

  12. Inhalant-Abuse Myocarditis Diagnosed by Cardiac Magnetic Resonance.

    Science.gov (United States)

    Dinsfriend, William; Rao, Krishnasree; Matulevicius, Susan

    2016-06-01

    Multiple reports of toxic myocarditis from inhalant abuse have been reported. We now report the case of a 23-year-old man found to have toxic myocarditis from inhalation of a hydrocarbon. The diagnosis was made by means of cardiac magnetic resonance imaging with delayed enhancement. The use of cardiac magnetic resonance to diagnose myocarditis has become increasingly common in clinical medicine, although there is not a universally accepted criterion for diagnosis. We appear to be the first to document a case of toxic myocarditis diagnosed by cardiac magnetic resonance. In patients with a history of drug abuse who present with clinical findings that suggest myocarditis or pericarditis, cardiac magnetic resonance can be considered to support the diagnosis.

  13. Magnetic resonance imaging- physical principles and clinical application

    International Nuclear Information System (INIS)

    Tavri, Omprakash J.

    1996-01-01

    The advances in equipment and knowledge related to radiology are occurring at an astonishingly rapid rate. On November 8, 1895, William Conrad Roentgen discovered x-rays. In 1972, Godfrey Hounsfield and George Ambrose introduced computec tomography at a meeting of the British Institute of Radiology. In the same year, Paul Lauterbur published the idea of spatially resolving nuclear magnetic resonance samples, naming it zeugmatography. In 1977, Waldo Hinshaw and co-workers published a magnetic resonance image of a human hand and wrist, and by 1981 several centres were obtaining clinical magnetic resonance (MR) images. In a very short time, magnetic resonance imaging (MRI) has gained acceptance as a clinically useful imaging tool. (author)

  14. 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

  15. Low field magnetic resonance imaging

    Science.gov (United States)

    Pines, Alexander; Sakellariou, Dimitrios; Meriles, Carlos A.; Trabesinger, Andreas H.

    2010-07-13

    A method and system of magnetic resonance imaging does not need a large homogenous field to truncate a gradient field. Spatial information is encoded into the spin magnetization by allowing the magnetization to evolve in a non-truncated gradient field and inducing a set of 180 degree rotations prior to signal acquisition.

  16. [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)

  17. Magnetic Resonance Imaging (MRI) -- Head

    Medline Plus

    Full Text Available ... by the interpreting radiologist. Frequently, the differentiation of abnormal (diseased) tissue from normal tissues is better with ... Tumor Treatment Magnetic Resonance Imaging (MRI) Safety Alzheimer's Disease Head Injury Brain Tumors Images related to Magnetic ...

  18. Tuning Coler Magnetic Current Apparatus with Magneto-Acoustic Resonance

    Science.gov (United States)

    Ludwig, Thorsten

    An attempt was made to tune the Coler magnetic current apparatus with the magneto acoustic resonance of the magnetic rods. Measurements with a replica of the famous Coler "Magnetstromapparat" were conducted. In order to tune the acoustic, magnetic and electric resonance circuits of the Coler device the magneto-acoustic resonance was measured with a frequency scan through a function generator and a lock-in amplifier. The frequency generator was powering a driving coil, while the lock-in was connected to a pickup coil. Both coils were placed on a magnetic rod. Resonances were observed up to the 17th harmonic. The quality Q of the observed resonances was 270. To study the magneto-acoustic resonance in the time domain a pair of Permendur rods were employed. The magneto-acoustic resonances of the Permendur rods were observed with an oscilloscope. Spectra of the magneto acoustic resonance were measured for the Permendur rods and for a Coler replica magnet in the frequency range from 25 kHz to 380 kHz. The next step was to bring the resonances of the Permendur rods close together so that they overlap. The 10thharmonic was chosen because it was close to the 180 kHz that Hans Coler related to ferromagnetism. Further more magneto-acoustic coupling between the Permendur rods was studied. Finally the question was explored if Hans Coler converted vacuum fluctuations via magnetic and acoustic resonance into electricity. There is a strong connection between magnetism and quantum field zero point energy (ZPE). An outlook is given on next steps in the experiments to unveil the working mechanism of the Coler magnetic current apparatus.

  19. Migraine and magnetic resonance spectroscopy

    DEFF Research Database (Denmark)

    Younis, Samaira; Hougaard, Anders; Vestergaard, Mark B.

    2017-01-01

    Purpose of review: To present an updated and streamlined overview of the metabolic and biochemical aspect of the migraine pathophysiology based on findings from phosphorous (31P) and hydrogen (1H) magnetic resonance spectroscopy (MRS) studies. Recent findings: Despite of the variation in the meth......Purpose of review: To present an updated and streamlined overview of the metabolic and biochemical aspect of the migraine pathophysiology based on findings from phosphorous (31P) and hydrogen (1H) magnetic resonance spectroscopy (MRS) studies. Recent findings: Despite of the variation...

  20. Rotational characteristics in the resonance state of the HTSC-permanent magnet hybrid magnetic bearing

    Energy Technology Data Exchange (ETDEWEB)

    Morii, Y.; Sukedai, M. [Kansai University, 3-3-35 Yamate-cho, Suita, Osaka 564-8680 (Japan); Ohashi, S., E-mail: ohashi@kansai-u.ac.jp [Kansai University, 3-3-35 Yamate-cho, Suita, Osaka 564-8680 (Japan)

    2011-11-15

    The hybrid magnetic bearing has been developed. In the hybrid system, effect of the pinning force becomes smaller. Influence of the vibration and the gradient angle in the resonance state is large. The resonance frequency becomes small in the hybrid bearing system. The hybrid magnetic bearing using permanent magnets and the high-Tc bulk superconductor (HTSC) has been developed. Repulsive force of the permanent magnet is introduced to increase the load weight of the magnetic bearing. Effect of the hybrid system has been shown. In this paper, influence of the hybrid system on the dynamic characteristics of the rotor is studied. The rotational characteristics in the mechanical resonance state are studied, and the equivalent magnetic spring coefficient is estimated from the experimental results of the load weight. The resonance frequency is measured by the rotation experiments. The rotor achieves stable levitation even in the resonance state. In the hybrid system, effect of the pinning force becomes smaller than that of the lateral force generated by the repulsive force between the two permanent magnets at the smaller air gap. Thus influence of the lateral vibration and the gradient angle in the resonance state becomes larger at a smaller air gap. The equivalent magnetic spring coefficient becomes also small, and the resonance frequency becomes small in the hybrid bearing system.

  1. Characterization of human breast disease using phosphorus magnetic resonance spectroscopy and proton magnetic resonance imaging

    International Nuclear Information System (INIS)

    Merchant, T.E.

    1992-01-01

    This thesis provides the fundamental characterization and differentiation of breast tissues using in vivo and ex vivo MR techniques in the hope that these techniques and experimental findings will be used on a larger scale and in a predictive manner in order to improve the specificity of diagnosis and treatment of breast cancer. In this dissertation, clinical studies were performed using proton magnetic resonance imaging and phosphorus magnetic resonance spectro-scopy ( 31 P MRS) to characterize and differentiate malignant breast tumors, benign breast tumors and normal breast tissues in vivo. These studies were carried out following the methodical characterization of chemical extracts of malignant breast tumor, benign breast tumor and normal breast parenchymal surgical tissue specimens using high resolution 31 P MRS. Alterations in breast tissue metabolism, as a result of pathological processes, were postulated to be responsible for measurable differences between malignant breast tumors, benign breast tumors and normal breast tissues using magnetic resonance techniques. (author). 365 refs.; 37 figs.; 25 tabs

  2. Cardiovascular magnetic resonance in congenital heart disease

    International Nuclear Information System (INIS)

    Cazacu, A.; Ciubotaru, A.

    2010-01-01

    The increasing prevalence of congenital heart disease can be attributed to major improvements in diagnosis and treatment. Cardiovascular magnetic resonance imaging plays an important role in the clinical management strategy of patients with congenital heart disease. The development of new cardiovascular magnetic resonance (CMR) techniques allows comprehensive assessment of complex cardiac anatomy and function and provides information about the long-term residual post-operative lesions and complications of surgery. It overcomes many of the limitations of echocardiography and cardiac catheterization. This review evaluates the role of cardiovascular magnetic resonance imaging modality in the management of subject with congenital heart disease (CHD). (authors)

  3. Children's (Pediatric) Magnetic Resonance Imaging

    Medline Plus

    Full Text Available ... Related Articles and Media Catheter Angiography Magnetic Resonance, Functional (fMRI) - Brain Children's (Pediatric) CT (Computed Tomography) Magnetic ... the possible charges you will incur. Web page review process: This Web page is reviewed regularly by ...

  4. Magnetic resonance imaging of the central nervous system

    International Nuclear Information System (INIS)

    Brant-Zawadzki, M.; Norman, D.

    1987-01-01

    This book presents the papers on technological advancement and diagnostic uses g magnetic resonance imaging. A comparative evaluation with computerized tomography is presented. Topics covered are imaging principles g magnetic resonance;instrumentation of magnetic resonance (MR);pathophysiology;quality and limitations g images;NMR imaging of brain and spinal cord;MR spectroscopy and its applications;neuroanatomy;Congenital malformations of brain and MR imaging;planning g MR imaging of spine and head and neck imaging

  5. Nuclear magnetic resonance spectroscopy and imaging

    International Nuclear Information System (INIS)

    Jiang Weiping; Wang Qi; Zhou Xin

    2013-01-01

    This paper briefly introduces the basic principle of nuclear magnetic resonance (NMR). Protein's structures and functions and dynamics studied by liquid NMR are elaborated; methods for enhancing the resolution of solid state NMR and its applications are discussed; the principle of magnetic resonance imaging (MRI) is interpreted, and applications in different aspects are reviewed. Finally, the progress of NMR is commented. (authors)

  6. Diagnostic apparatus employing nuclear magnetic resonance

    International Nuclear Information System (INIS)

    Hoshino, K.; Yamada, N.; Yoshitome, E.; Matsuura, H.

    1987-01-01

    An NMR diagnostic apparatus is described comprising means for applying a primary magnetic field to a subject; means for applying RF pulses to the subject to give nuclear magnetic resonance to the nuclei of atoms in the subject; means for applying gradient magnetic fields to project an NMR signal of the nuclei at least in one direction; means for observing the NMR signal projected by the gradient magnetic fields applying means; and arithmetic means for constructing a distribution of information on resonance energy as an image from an output signal from the observing means; wherein the gradient magnetic fields applying means comprises means for applying the gradient magnetic fields at a predetermined time and for not applying the gradient magnetic fields at another predetermined time, during the time period of one view; and wherein the gradient magnetic fields applying means further comprises means for measuring the NMR signal during the predetermined time when the gradient magnetic fields are applied, and means for measuring the intensity of the primary magnetic field during the other predetermined time when no gradient magnetic fields are applied

  7. Children's (Pediatric) Magnetic Resonance Imaging

    Medline Plus

    Full Text Available ... immediately after the exam. A few patients experience side effects from the contrast material, including nausea and local ... Related Articles and Media Catheter Angiography Magnetic Resonance, Functional (fMRI) - Brain Children's (Pediatric) CT (Computed Tomography) Magnetic ...

  8. Medulloblastoma: correlation among findings of conventional magnetic resonance imaging, diffusion-weighted imaging and proton magnetic resonance spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Fonte, Mariana Vieira de Melo da; Otaduy, Maria Concepcion Garcia; Lucato, Leandro Tavares; Reed, Umbertina Conti; Leite, Claudia da Costa [Universidade de Sao Paulo (USP), Sao Paulo, SP (Brazil). Hospital das Clinicas. Inst. de Radiologia]. E-mail: mvmfonte@uol.com.br; Costa, Maria Olivia Rodrigues; Amaral, Raquel Portugal Guimaraes [Universidade de Sao Paulo (USP), Sao Paulo, SP (Brazil). Faculdade de Medicina. Dept. de Radiologia; Reed, Umbertina Conti [Universidade de Sao Paulo (USP), Sao Paulo, SP (Brazil). Faculdade de Medicina. Dept. de Neurologia; Rosemberg, Sergio [Universidade de Sao Paulo (USP), Sao Paulo, SP (Brazil). Hospital das Clinicas. Dept. de Patologia

    2008-11-15

    To correlate imaging findings of medulloblastomas at conventional magnetic resonance imaging, diffusion-weighted imaging and proton magnetic resonance spectroscopy, comparing them with data in the literature. Preoperative magnetic resonance imaging studies of nine pediatric patients with histologically confirmed medulloblastomas (eight desmoplastic medulloblastoma, and one giant cell medulloblastoma) were retrospectively reviewed, considering demographics as well as tumors characteristics such as localization, morphology, signal intensity, contrast-enhancement, dissemination, and diffusion-weighted imaging and spectroscopy findings. In most of cases the tumors were centered in the cerebellar vermis (77.8%), predominantly solid (88.9%), hypointense on T 1-weighted images and intermediate/hyperintense on T 2-FLAIR-weighted images, with heterogeneous enhancement (100%), tumor dissemination/extension (77.8%) and limited water molecule mobility (100%). Proton spectroscopy acquired with STEAM technique (n = 6) demonstrated decreased Na a / Cr ratio (83.3%) and increased Co/Cr (100%) and ml/Cr (66.7%) ratios; and with PRESS technique (n = 7) demonstrated lactate peak (57.1%). Macroscopic magnetic resonance imaging findings in association with biochemical features of medulloblastomas have been useful in the differentiation among the most frequent posterior fossa tumors. (author)

  9. Medulloblastoma: correlation among findings of conventional magnetic resonance imaging, diffusion-weighted imaging and proton magnetic resonance spectroscopy

    International Nuclear Information System (INIS)

    Fonte, Mariana Vieira de Melo da; Otaduy, Maria Concepcion Garcia; Lucato, Leandro Tavares; Reed, Umbertina Conti; Leite, Claudia da Costa; Costa, Maria Olivia Rodrigues; Amaral, Raquel Portugal Guimaraes; Reed, Umbertina Conti; Rosemberg, Sergio

    2008-01-01

    To correlate imaging findings of medulloblastomas at conventional magnetic resonance imaging, diffusion-weighted imaging and proton magnetic resonance spectroscopy, comparing them with data in the literature. Preoperative magnetic resonance imaging studies of nine pediatric patients with histologically confirmed medulloblastomas (eight desmoplastic medulloblastoma, and one giant cell medulloblastoma) were retrospectively reviewed, considering demographics as well as tumors characteristics such as localization, morphology, signal intensity, contrast-enhancement, dissemination, and diffusion-weighted imaging and spectroscopy findings. In most of cases the tumors were centered in the cerebellar vermis (77.8%), predominantly solid (88.9%), hypointense on T 1-weighted images and intermediate/hyperintense on T 2-FLAIR-weighted images, with heterogeneous enhancement (100%), tumor dissemination/extension (77.8%) and limited water molecule mobility (100%). Proton spectroscopy acquired with STEAM technique (n = 6) demonstrated decreased Na a / Cr ratio (83.3%) and increased Co/Cr (100%) and ml/Cr (66.7%) ratios; and with PRESS technique (n = 7) demonstrated lactate peak (57.1%). Macroscopic magnetic resonance imaging findings in association with biochemical features of medulloblastomas have been useful in the differentiation among the most frequent posterior fossa tumors. (author)

  10. 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.

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

    Energy Technology Data Exchange (ETDEWEB)

    De Filippo, Massimo [Department of Clinical Sciences, Section of Radiological Sciences, University of Parma, Parma Hospital, Via Gramsci, 14, 43100 Parma (Italy)], E-mail: massimo.defilippo@unipr.it; 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.

  12. Evaluation of nuclear magnetic resonance spectroscopy variability

    Energy Technology Data Exchange (ETDEWEB)

    Barreto, Felipe Rodrigues; Salmon, Carlos Ernesto Garrido, E-mail: garrido@ffclrp.usp.br [Universidade de Sao Paulo (FFCLRP/USP), Ribeirao Preto, SP (Brazil). Fac. de Filisofia, Ciencias e Letras; Otaduy, Maria Concepcion Garcia [Universidade de Sao Paulo (FAMUS/USP), Sao Paulo, SP (Brazil). Fac. de Medicina. Departamento de Radiologia

    2014-11-01

    Introduction: the intrinsically high sensitivity of Magnetic Resonance Spectroscopy (MRS) causes considerable variability in metabolite quantification. In this study, we evaluated the variability of MRS in two research centers using the same model of magnetic resonance image scanner. Methods: two metabolic phantoms were created to simulate magnetic resonance spectra from in vivo hippocampus. The phantoms were filled with the same basic solution containing the following metabolites: N-acetyl-aspartate, creatine, choline, glutamate, glutamine and inositol. Spectra were acquired over 15 months on 26 acquisition dates, resulting in a total of 130 spectra per center. Results: the phantoms did not undergo any physical changes during the 15-month period. Temporal analysis from both centers showed mean metabolic variations of 3.7% in acquisitions on the same day and of 8.7% over the 15-month period. Conclusion: The low deviations demonstrated here, combined with the high specificity of Magnetic Resonance Spectroscopy, confirm that it is feasible to use this technique in multicenter studies in neuroscience research. (author)

  13. Magnetic Resonance Imaging (MRI): Lumbar Spine (For Parents)

    Science.gov (United States)

    ... Staying Safe Videos for Educators Search English Español Magnetic Resonance Imaging (MRI): Lumbar Spine KidsHealth / For Parents / Magnetic Resonance Imaging (MRI): Lumbar Spine What's in this article? ...

  14. 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.)

  15. Technical errors in MR arthrography

    Energy Technology Data Exchange (ETDEWEB)

    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.)

  16. Nuclear magnetic resonance and earth magnetic field

    International Nuclear Information System (INIS)

    Anon.

    1998-01-01

    Nuclear magnetic resonance concerns nuclei whose spin is different from 0. These nuclei exposed to a magnetic field is comparable to a peg top spinning around its axis while being moved by a precession movement called Larmor precession. This article presents an experiment whose aim is to reveal nuclear magnetism of nuclei by observing Larmor precession phenomena due to the earth magnetic field. The earth magnetic field being too weak, it is necessary to increase the magnetization of the sample during a polarization phase. First the sample is submitted to a magnetic field B perpendicular to the earth magnetic field B 0 , then B is cut off and the nuclei move back to their equilibrium position by executing a precession movement due to B 0 field. (A.C.)

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

    Energy Technology Data Exchange (ETDEWEB)

    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.)

  18. Resonance double magnetic bremsstrahlung in a strong magnetic field

    International Nuclear Information System (INIS)

    Fomin, P.I.; Kholodov, R.I.

    2003-01-01

    The possibility of resonance double magnetic bremsstrahlung in the approximation of weakly excited electron states in a strong external magnetic field is analyzed. The differential probability of this process in the Breit-Wigner form is obtained. The probability of double magnetic bremsstrahlung (second-order process of perturbation theory) is compared with the probability of magnetic bremsstrahlung (first-order process of perturbation theory)

  19. Evaluation of urogenital fistulas by magnetic resonance urography

    International Nuclear Information System (INIS)

    Mamere, Augusto Elias; Coelho, Rafael Darahem Souza; Cecin, Alexandre Oliveira; Feltrin, Leonir Terezinha; Lucchesi, Fabiano Rubiao; Seabra, Daniel

    2008-01-01

    Objective: Vesicovaginal and ureterovaginal fistulas are unusual complications secondary to pelvic surgery or pelvic diseases. The therapeutic success in these cases depends on an appropriate preoperative evaluation for diagnosis and visualization of the fistulous tract. The present study is aimed at demonstrating the potential of magnetic resonance urography for the diagnosis of vesicovaginal and ureterovaginal fistulas as well as for defining the fistulous tracts. Materials And Methods: Seven female patients clinically diagnosed with vesicovaginal or ureterovaginal fistulas had their medical records, radiological and magnetic resonance images retrospectively reviewed. Magnetic resonance urography included 3D-HASTE sequences with fat saturation. Results: Six patients presented vesicovaginal fistulas and, in one patient, a right-sided ureterovaginal fistula was diagnosed. Magnetic resonance urography allowed the demonstration of the fistulous tract in six (85.7%) of the seven patients evaluated in the present study, without the need of bladder catheterization or contrast injection. Conclusion: This study demonstrates both the potential and applicability of magnetic resonance urography in the evaluation of these types of fistulas. (author)

  20. Object-oriented magnetic resonance classes and objects, calculations and computations

    CERN Document Server

    Mehring, Michael

    2001-01-01

    This book presents, for the first time, a unified treatment of the quantum mechanisms of magnetic resonance, including both nuclear magnetic resonance (NMR) and electron spin resonance (ESR). Magnetic resonance is perhaps the most advanced type of spectroscopy and it is applied in biology, chemistry, physics, material science, and medicine. If applied in conjunction with spectroscopy, the imaging version of magnetic resonance has no counterpart in any type of experimental technique. The authors present explanations and applications from fundamental to advanced levels. Additionally, the

  1. Magnetic resonance enterography in pediatric celiac disease.

    Science.gov (United States)

    Koc, Gonca; Doganay, Selim; Sevinc, Eylem; Deniz, Kemal; Chavhan, Govind; Gorkem, Sureyya B; Karacabey, Neslihan; Dogan, Mehmet S; Coskun, Abdulhakim; Aslan, Duran

    To assess if magnetic resonance enterography is capable of showing evidence/extent of disease in pediatric patients with biopsy-proven celiac disease by comparing with a control group, and to correlate the magnetic resonance enterography findings with anti-endomysial antibody level, which is an indicator of gluten-free dietary compliance. Thirty-one pediatric patients (mean age 11.7±3.1 years) with biopsy-proven celiac disease and 40 pediatric patients as a control group were recruited in the study. The magnetic resonance enterography images of both patients with celiac disease and those of the control group were evaluated by two pediatric radiologists in a blinded manner for the mucosal pattern, presence of wall thickening, luminal distention of the small bowel, and extra-intestinal findings. Patient charts were reviewed to note clinical features and laboratory findings. The histopathologic review of the duodenal biopsies was re-conducted. The mean duration of the disease was 5.6±1.8 years (range: 3-7.2 years). In 24 (77%) of the patients, anti-endomysial antibody levels were elevated (mean 119.2±66.6RU/mL). Magnetic resonance enterography revealed normal fold pattern in all the patients. Ten (32%) patients had enlarged mesenteric lymph nodes. Although a majority of the patients had elevated anti-endomysial antibody levels indicating poor dietary compliance, magnetic resonance enterography did not show any mucosal abnormality associated with the inability of magnetic resonance enterography to detect mild/early changes of celiac disease in children. Therefore, it may not be useful for the follow-up of pediatric celiac disease. Copyright © 2017 Sociedade Brasileira de Pediatria. Published by Elsevier Editora Ltda. All rights reserved.

  2. Theoretical study of ferromagnetic resonance in exchange - coupled magnetic / nonmagnetic / magnetic multilayer structure

    International Nuclear Information System (INIS)

    Oezdogan, K.; Oezdemir, M.; Yalcin, O.; Aktas, B.

    2002-01-01

    The dispersion relation on ferromagnetic films was calculation by using torque equation of motion with a damping term. The total energy including zeeman, demagnetizing and anisotropy energy terms was used to get ferromagnetic resonance frequency for both uniform and higher order spin wave modes. In antiferromagnetic films, the torque equation of motion for each sub-lattice were written to derive an expression for the dispersion relation. The magnetic trilayer system under investigation consist of two ferromagnetic layers separated by a nonmagnetic layer. The dispersion relation of magnetic/nonmagnetic/magnetic three layers is calculated by using Landau-Lifshitz dynamic equation of motion for the magnetization with interlayer exchange energy. As for the exchange-coupled resonance of ferromagnetic resonance (FMR), the theoretical study has been calculated for both symmetrical and asymmetrical structures. In this systems, the exchange-coupling parameter A 12 between neighboring layers was used to get resonance fields as a function of the angle between the magnetization vectors of each magnetic layers

  3. Magnetic elliptical polarization of Schumann resonances

    International Nuclear Information System (INIS)

    Sentman, D.D.

    1987-01-01

    Measurements of orthogonal, horizontal components of the magnetic field in the ELF range obtained during September 1985 show that the Schumann resonance eigenfrequencies determined separately for the north-south and east-west magnetic components differ by as much as 0.5 Hz, suggesting that the underlying magnetic signal is not linearly polarized at such times. The high degree of magnetic ellipticity found suggests that the side multiplets of the Schumann resonances corresponding to azimuthally inhomogeneous normal modes are strongly excited in the highly asymmetric earth-ionosphere cavity. The dominant sense of polarization over the measurement passband is found to be right-handed during local daylight hours, and to be left-handed during local nighttime hours. 16 references

  4. Functional magnetic resonance imaging by visual stimulation

    International Nuclear Information System (INIS)

    Nishimura, Yukiko; Negoro, Kiyoshi; Morimatsu, Mitsunori; Hashida, Masahiro

    1996-01-01

    We evaluated functional magnetic resonance images obtained in 8 healthy subjects in response to visual stimulation using a conventional clinical magnetic resonance imaging system with multi-slice spin-echo echo planar imaging. Activation in the visual cortex was clearly demonstrated by the multi-slice experiment with a task-related change in signal intensity. In addition to the primary visual cortex, other areas were also activated by a complicated visual task. Multi-slice spin-echo echo planar imaging offers high temporal resolution and allows the three-dimensional analysis of brain function. Functional magnetic resonance imaging provides a useful noninvasive method of mapping brain function. (author)

  5. 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.)

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2009-11-15

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

  7. Musculoskeletal applications of magnetic resonance imaging: Council on Scientific Affairs

    International Nuclear Information System (INIS)

    Harms, S.E.; Fisher, C.F.; Fulmer, J.M.

    1989-01-01

    Magnetic resonance imaging provides superior contrast, resolution, and multiplanar imaging capability, allowing excellent definition of soft-tissue and bone marrow abnormalities. For these reasons, magnetic resonance imaging has become a major diagnostic imaging method for the evaluation of many musculoskeletal disorders. The applications of magnetic resonance imaging for musculoskeletal diagnosis are summarized and examples of common clinical situations are given. General guidelines are suggested for the musculoskeletal applications of magnetic resonance imaging

  8. 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

  9. 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

    Energy Technology Data Exchange (ETDEWEB)

    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.)

  10. Magnetic resonance of native defects of spin-Peierls magnetics CuGeO3

    International Nuclear Information System (INIS)

    Smirnov, A.I.; Glazkov, V.N.; Leonyuk, L.I.; Vetkin, A.G.; Eremina, R.M.

    1998-01-01

    Magnetic resonance within 9-75 GHz frequency range and 1.2-25 K temperature range was studied in pure monocrystalline spin-Peierls CuGwO 3 . Splitting of the magnetic resonance line is observed within temperature range below 5 K. Analysis of magnetic resonance spectra at various directions of magnetic field and under various temperatures enables to set off EPR-signals of spin-Peierls phase defects with S=1/2 and defects with S=1 from these components; g-factor corresponding to these EPR signals is similar one and close to values typical for Cu 2+ ion [ru

  11. Green’s function theory of ferromagnetic resonance in magnetic superlattices with damping

    International Nuclear Information System (INIS)

    Qiu, R.K.; Guo, F.F.; Zhang, Z.D.

    2016-01-01

    We explore a quantum Green’s-function method to study the resonance absorption of magnetic materials. The relationship between the resonance magnon (spin wave) density and the resonance frequency of a superlattice consisting of two magnetic layers with damping and antiferromagnetic interlayer exchange coupling is studied. The effects of temperature, interlayer coupling, anisotropy, external magnetic field and damping on the the resonance frequency and resonance magnon density are investigated. The resonance excitation probability for a magnon is proportional to the resonance magnon density. In the classic methods, the imaginary part of magnetic permeability represents the resonance absorption in magnetic materials. In the quantum approach, the resonance magnon density can be used to estimate the strength of the resonance absorption. In the present work, a quantum approach is developed to study resonance absorption of magnetic materials and the results show the method to obtain a magnetic multilayered materials with both high resonance frequency and high resonance absorption.

  12. Green’s function theory of ferromagnetic resonance in magnetic superlattices with damping

    Energy Technology Data Exchange (ETDEWEB)

    Qiu, R.K., E-mail: rkqiu@163.com [Shenyang University of Technology, Shenyang 110870 (China); Guo, F.F. [Shenyang University of Technology, Shenyang 110870 (China); Zhang, Z.D. [Shenyang National Laboratory for Materials Science, Institute of Metal Research, Chinese Academy of Sciences, Shenyang 110016 (China)

    2016-02-01

    We explore a quantum Green’s-function method to study the resonance absorption of magnetic materials. The relationship between the resonance magnon (spin wave) density and the resonance frequency of a superlattice consisting of two magnetic layers with damping and antiferromagnetic interlayer exchange coupling is studied. The effects of temperature, interlayer coupling, anisotropy, external magnetic field and damping on the the resonance frequency and resonance magnon density are investigated. The resonance excitation probability for a magnon is proportional to the resonance magnon density. In the classic methods, the imaginary part of magnetic permeability represents the resonance absorption in magnetic materials. In the quantum approach, the resonance magnon density can be used to estimate the strength of the resonance absorption. In the present work, a quantum approach is developed to study resonance absorption of magnetic materials and the results show the method to obtain a magnetic multilayered materials with both high resonance frequency and high resonance absorption.

  13. Least Squares Magnetic-Field Optimization for Portable Nuclear Magnetic Resonance Magnet Design

    International Nuclear Information System (INIS)

    Paulsen, Jeffrey L; Franck, John; Demas, Vasiliki; Bouchard, Louis-S.

    2008-01-01

    Single-sided and mobile nuclear magnetic resonance (NMR) sensors have the advantages of portability, low cost, and low power consumption compared to conventional high-field NMR and magnetic resonance imaging (MRI) systems. We present fast, flexible, and easy-to-implement target field algorithms for mobile NMR and MRI magnet design. The optimization finds a global optimum in a cost function that minimizes the error in the target magnetic field in the sense of least squares. When the technique is tested on a ring array of permanent-magnet elements, the solution matches the classical dipole Halbach solution. For a single-sided handheld NMR sensor, the algorithm yields a 640 G field homogeneous to 16,100 ppm across a 1.9 cc volume located 1.5 cm above the top of the magnets and homogeneous to 32,200 ppm over a 7.6 cc volume. This regime is adequate for MRI applications. We demonstrate that the homogeneous region can be continuously moved away from the sensor by rotating magnet rod elements, opening the way for NMR sensors with adjustable 'sensitive volumes'

  14. Clinical magnetic resonance: imaging and spectroscopy

    International Nuclear Information System (INIS)

    Andrew, E.R.; Bydder, Graeme; Griffiths, John; Iles, Richard; Styles, Peter

    1990-01-01

    This book begins with a readable, comprehensive but non-mathematical introduction to the basic underlying principles of magnetic resonance. Further chapters include information on the theory and principles of MRI and MRS, the interpretation of MR images, the clinical applications and scope of MRI and MRS, practical aspects of spectroscopy and magnetic resonance, and also the practical problems associated with the siting, safety and operation of large MRI and MRS equipment. (author)

  15. Magnetic resonance in prenatal diagnosis of thoracic anomalies

    International Nuclear Information System (INIS)

    Pietrani, M.; Elias, D.; Wojakowski, A.; Fataljaef, V.; Carcano, M.; Otano, L.

    2007-01-01

    The objective of this article is to communicate the experience in the evaluation of fetal anomalies thoracic by means of magnetic resonance. Between January, 2001 - March, 2007 16 fetus were evaluated by means of magnetic resonance with echographic diagnosis of thoracic anomalies. An equipment of 1.5 TESLA was used. The thoracic anatomy was valued in general. At the presence of discovering pulmonary mass, their size, volume and intensity of sign were determined. The echographic and magnetic resonance findings were checked against the perinatal results [es

  16. Role of chelates in magnetic resonance imaging studies

    Directory of Open Access Journals (Sweden)

    Tripathi Laxmi

    2009-01-01

    Full Text Available Imaging studies are tests performed with a variety of techniques that produce pictures of the inside of a patient′s body. Magnetic resonance imaging (MRI is an imaging technique based on the principles of nuclear magnetic resonance. MRI uses a powerful magnetic field, radio waves, and a computer to produce detailed pictures of organs, soft tissues, bone, and virtually all other internal body structures. Chelates have a wide application in such imaging techniques. Chelates in imaging studies are used alone as radioactive agents or conjugated to monoclonal antibodies or to DNA as radioactive agents. Technetium chelates and gadolinium chelates are being widely used as magnetic resonance contrast media.

  17. Recommendations concerning magnetic resonance spectroscopy

    International Nuclear Information System (INIS)

    1986-01-01

    In medicine the technique of nuclear magnetic resonance (NMR) is applied in the form of in vivo nuclear magnetic resonance spectroscopy (MRS). In vivo MRS can be carried out non-invasively. The committee of the Dutch Health Council briefly discusses the qualities and potentialities of the nuclei that will probably be used in future clinical spectroscopy: 31 P, 13 C, 1 H (and possibly 19 F and 23 Na). The committee discusses several possibilities of combining imaging and spectroscopy. The imaging of nuclei other than protons is also possible with MRS. Potential applications are considered in oncology, cardiology, neurology and hepatology. (Auth.)

  18. Prebiopsy magnetic resonance spectroscopy and imaging in the diagnosis of prostate cancer

    International Nuclear Information System (INIS)

    Kumar, V.; Jagannathan, N.R.; Thulkar, S.; Kumar, R.

    2012-01-01

    Existing screening investigations for the diagnosis of early prostate cancer lack specificity, resulting in a high negative biopsy rate. There is increasing interest in the use of various magnetic resonance methods for improving the yield of transrectal ultrasound-guided biopsies of the prostate in men suspected to have prostate cancer. We review the existing status of such investigations. A literature search was carried out using the Pubmed database to identify articles related to magnetic resonance methods for diagnosing prostate cancer. References from these articles were also extracted and reviewed. Recent studies have focused on prebiopsy magnetic resonance investigations using conventional magnetic resonance imaging, dynamic contrast enhanced magnetic resonance imaging, diffusion weighted magnetic resonance imaging, magnetization transfer imaging and magnetic resonance spectroscopy of the prostate. This marks a shift from the earlier strategy of carrying out postbiopsy magnetic resonance investigations. Prebiopsy magnetic resonance investigations has been useful in identifying patients who are more likely to have a biopsy positive for malignancy. Prebiopsy magnetic resonance investigations has a potential role in increasing specificity of screening for early prostate cancer. It has a role in the targeting of biopsy sites, avoiding unnecessary biopsies and predicting the outcome of biopsies. (author)

  19. Magnetic Resonance Imaging of Surgical Implants Made from Weak Magnetic Materials

    Science.gov (United States)

    Gogola, D.; Krafčík, A.; Štrbák, O.; Frollo, I.

    2013-08-01

    Materials with high magnetic susceptibility cause local inhomogeneities in the main field of the magnetic resonance (MR) tomograph. These inhomogeneities lead to loss of phase coherence, and thus to a rapid loss of signal in the image. In our research we investigated inhomogeneous field of magnetic implants such as magnetic fibers, designed for inner suture during surgery. The magnetic field inhomogeneities were studied at low magnetic planar phantom, which was made from four thin strips of magnetic tape, arranged grid-wise. We optimized the properties of imaging sequences with the aim to find the best setup for magnetic fiber visualization. These fibers can be potentially exploited in surgery for internal stitches. Stitches can be visualized by the magnetic resonance imaging (MRI) method after surgery. This study shows that the imaging of magnetic implants is possible by using the low field MRI systems, without the use of complicated post processing techniques (e.g., IDEAL).

  20. Magnetic resonance instrumentation

    International Nuclear Information System (INIS)

    Bell, R.A.

    1987-01-01

    Magnetic resonance (MR), while opening new vistas to diagnostic medicine, utilizes equipment that is unfamiliar to most clinicians. Beyond learning to cope with new terms, such as spin-echo, T1, T2, and spin density, health care professionals are faced with the inclusion of magnetic and radiofrequency effects in their facilities produced by a complex array of devices. It is the purpose of this chapter to outline the components of an MR imaging system, to discuss their functions, and to note the variations in equipment commercially available

  1. Parenchymal abnormalities in cerebral venous thrombosis: findings of magnetic resonance imaging and magnetic resonance angiography

    International Nuclear Information System (INIS)

    Ferreira, Clecia Santos; Pellini, Marcos; Boasquevisque, Edson; Souza, Luis Alberto M. de

    2006-01-01

    Objective: to determine the frequency and localization of parenchymal abnormalities in cerebral venous thrombosis on magnetic resonance imaging and magnetic resonance angiography as well as their correlation with the territory and affected venous drainage. Materials and methods: retrospective analysis (1996 to 2004) of 21 patients (3 male and 18 female) age range between 3 and 82 years (mean 40 years, median 36 years) with clinical and radiological diagnosis of cerebral venous thrombosis on magnetic resonance imaging and magnetic resonance angiography in 2D PC, 3D PC and contrast-enhanced 3D TOF sequences. The statistical analysis was performed with the qui-square test. Four patients had follow-up exams and three patients underwent digital subtraction angiography. Results: main predisposing factors were: infection, use of oral contraceptives, hormone replacement therapy and collagenosis. Predominant symptoms included: focal deficit, headache, alteration of consciousness level and seizures. Most frequent parenchymal manifestations were: cortical/subcortical edema or infarct, venous congestion and collateral circulation, meningeal enhancement and thalamic and basal ganglia edema or infarct. Occlusion occurred mainly in superior sagittal, left transverse, left sigmoid and straight sinuses. Cavernous sinus and cortical veins thrombosis are uncommon events. Conclusion: cerebral venous thrombosis is an uncommon cause of stroke, with favorable prognosis because of its reversibility. Diagnosis is highly dependent on the radiologist capacity to recognize the presentations of this disease, principally in cases where the diagnosis is suggested by parenchymal abnormalities rather than necessarily by visualization of the thrombus itself. An accurate and rapid diagnosis allows an immediate treatment, reducing the morbidity and mortality rates. (author)

  2. Nuclear magnetic resonance spectroscopy in organic chemistry. 2. ed.

    International Nuclear Information System (INIS)

    Zschunke, A.

    1977-01-01

    The fundamentals of nuclear magnetic resonance spectroscopy are discussed only briefly. The emphasis is laid on developing reader's ability to evaluate resonance spectra. The following topics are covered: principles of nuclear magnetic resonance spectroscopy; chemical shift and indirect nuclear spin coupling constants and their relation to the molecular structure; analysis of spectra; and uses for structural analysis and solution of kinetic problems, mainly with regard to organic compounds. Of interest to chemists and graduate students who want to make themselves acquainted with nuclear magnetic resonance spectroscopy

  3. Complications after liver transplantation: evaluation with magnetic resonance imaging, magnetic resonance cholangiography, and 3-dimensional contrast-enhanced magnetic resonance angiography in a single session

    International Nuclear Information System (INIS)

    Boraschi, P.; Donati, F.; Gigoni, R.; Salemi, S.; Urbani, L.; Filipponi, F.; Falaschi, F.; Bartolozzi, C.

    2008-01-01

    To evaluate a comprehensive magnetic resonance imaging (MRI) protocol as noninvasive diagnostic modality for simultaneous detection of parenchymal, biliary, and vascular complications after liver transplantation. Fifty-two liver transplant recipients suspected to have parenchymal, biliary, and (or) vascular complications underwent our MRI protocol at 1.5T unit using a phased array coil. After preliminary acquisition of axial T 1 w and T 2 w sequences, magnetic resonance cholangiography (MRC) was performed through a breath-hold, thin- and thick-slab, single-shot T 2 w sequence in the coronal plane. Contrast-enhanced magnetic resonance angiography (CEMRA) was obtained using a 3-dimensional coronal spoiled gradient-echo sequence, which enabled acquisition of 32 partitions 2.0 mm thick. A fixed dose of 20 ml gadobenate dimeglumine was administered at 2 mL/s. A post-contrast T 1 w sequence was also performed. Two observers in conference reviewed source images and 3-dimensional reconstructions to determine the presence of parenchymal, biliary, and vascular complications. MRI findings were correlated with surgery, endoscopic retrograde cholangiography (ERC), biopsy, digital subtraction angiography (DSA), and imaging follow-up. MRI revealed abnormal findings in 32 out of 52 patients (61%), including biliary complications (anastomotic and nonanastomotic strictures, and lithiasis) in 31, vascular disease (hepatic artery stenosis and thrombosis) in 9, and evidence of hepatic abscess and hematoma in 2. ERC confirmed findings of MRC in 30 cases, but suggested disease underestimation in 2. DSA confirmed 7 magnetic resonance angiogram (MRA) findings, but suggested disease overestimation in 2. MRI combined with MRC and CEMRA can provide a comprehensive assessment of parenchymal, biliary, and vascular complications in most recipients of liver transplantation. (author)

  4. Magnetic resonance imaging - first human images in Australia

    International Nuclear Information System (INIS)

    Baddeley, H.; Doddrell, D.M.; Brooks, W.M.; Field, J.; Irving, M.; Williams, J.E.

    1986-01-01

    The use of magnetic resonance imaging, in the demonstration of internal human anatomy and in the diagnosis of disease, has the major advantages that the technique is non-invasive, does not require the use of ionizing radiation and that it can demonstrate neurological and cardiovascular lesions that cannot be diagnosed easily by other imaging methods. The first magnetic resonance images of humans were obtained in Australia in October 1985 on the research instrument of the Queensland Medical Magnetic Resonance Research Centre, which is based at the Mater Hospital in Brisbane

  5. Magnetic resonance imaging of radiation optic neuropathy

    International Nuclear Information System (INIS)

    Zimmerman, C.F.; Schatz, N.J.; Glaser, J.S.

    1990-01-01

    Three patients with delayed radiation optic neuropathy after radiation therapy for parasellar neoplasms underwent magnetic resonance imaging. The affected optic nerves and chiasms showed enlargement and focal gadopentetate dimeglumine enhancement. The magnetic resonance imaging technique effectively detected and defined anterior visual pathway changes of radionecrosis and excluded the clinical possibility of visual loss because of tumor recurrence

  6. Giant magnetic modulation of a planar, hybrid metamolecule resonance

    International Nuclear Information System (INIS)

    Gregory, Simon A; Stenning, Gavin B G; Bowden, Graham J; De Groot, Peter A J; Zheludev, Nikolay I

    2014-01-01

    Coupling magnetic elements to metamaterial structures creates hybrid metamolecules with new opportunities. Here we report on the magnetic control of a metamolecule resonance, by utilizing the interaction between a single split ring resonator (SRR) and a magnetic thin film of permalloy. To suppress eddy current shielding, the permalloy films are patterned into arrays of 30–500 μm diameter discs. Strong hybridized resonances were observed at the anticrossing between the split ring resonance and the ferromagnetic resonance (FMR) of the permalloy. In particular, it is possible to achieve 40 dB modulation of the electric (symmetric) mode of the SRR on sweeping the applied magnetic field through the SRR/FMR anticrossing. The results open the way to the design of planar metamaterials, with potential applications in nonlinear metamaterials, tunable metamaterials and spintronics. (papers)

  7. Magnetic resonance imaging of muscle tears

    International Nuclear Information System (INIS)

    De Smet, A.A.; Fisher, D.R.; Heiner, J.P.; Keene, J.S.

    1990-01-01

    Magnetic resonance scans were obtained on 17 patients with acute, subacute, or chronic muscle tears. These patients presented with complaints of persistent pain or a palpable mass. Magnetic resonance findings were characterized according to alterations in muscle shape and the presence of abnormal high signal within the injured muscle. These areas of high signal were noted on both T1-weighted and T2-weighted scans and were presumed to represent areas of intramuscular hemorrhage. (orig.)

  8. Magnetic resonance of rubidium atoms passing through a multi-layered transmission magnetic grating

    International Nuclear Information System (INIS)

    Nagata, Y; Kurokawa, S; Hatakeyama, A

    2017-01-01

    We measured the magnetic resonance of rubidium atoms passing through periodic magnetic fields generated by two types of multi-layered transmission magnetic grating. One of the gratings reported here was assembled by stacking four layers of magnetic films so that the direction of magnetization alternated at each level. The other grating was assembled so that the magnetization at each level was aligned. For both types of grating, the experimental results were in good agreement with our calculations. We studied the feasibility of extending the frequency band of the grating and narrowing its resonance linewidth by performing calculations. For magnetic resonance precision spectroscopy, we conclude that the multi-layered transmission magnetic grating can generate periodic fields with narrower linewidths at higher frequencies when a larger number of layers are assembled at a shorter period length. Moreover, the frequency band of this type of grating can potentially achieve frequencies of up to hundreds of PHz. (paper)

  9. Magnetic resonance imaging of breast implants.

    Science.gov (United States)

    Shah, Mala; Tanna, Neil; Margolies, Laurie

    2014-12-01

    Silicone breast implants have significantly evolved since their introduction half a century ago, yet implant rupture remains a common and expected complication, especially in patients with earlier-generation implants. Magnetic resonance imaging is the primary modality for assessing the integrity of silicone implants and has excellent sensitivity and specificity, and the Food and Drug Administration currently recommends periodic magnetic resonance imaging screening for silent silicone breast implant rupture. Familiarity with the types of silicone implants and potential complications is essential for the radiologist. Signs of intracapsular rupture include the noose, droplet, subcapsular line, and linguine signs. Signs of extracapsular rupture include herniation of silicone with a capsular defect and extruded silicone material. Specific sequences including water and silicone suppression are essential for distinguishing rupture from other pathologies and artifacts. Magnetic resonance imaging provides valuable information about the integrity of silicone implants and associated complications.

  10. 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.

  11. Magnetic Resonance (MR) Defecography

    Science.gov (United States)

    ... to a CD or uploaded to a digital cloud server. Magnetic resonance (MR) defecography is a special ... with you. top of page What are the benefits vs. risks? Benefits MR defecography helps assess pelvic ...

  12. First national meeting of magnetic resonance and hyperfine interactions

    International Nuclear Information System (INIS)

    1985-07-01

    Works performed at CNEA's: Magnetic Resonance Division; Moessbauer Spectroscopy; Solid State Physics Division; Nuclear magnetic Resonance Laboratory and Theoretical Physics Group; Mossbauer Spectroscopy Group; Nuclear Quadrupole Resonance; Physics and Materials Group; Perturbed Angular Correlation and Moessbauer Spectroscopy and Physics Department. (M.E.L.) [es

  13. 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

  14. An introduction to magnetic resonance in medicine. 2. rev. ed.

    International Nuclear Information System (INIS)

    Rinck, P.A.; Muller, R.N.; Petersen, S.B.

    1990-01-01

    The second edition of this introduction to magnetic resonance in medicine is published five years after the first. During these years, magnetic resonance has established itself as a leading diagnostic modality in medicine. With the introduction of fast imaging methods and contrast agents, magnetic resonance imaging (MRI) and magnetic resonance spectroscopy (MRS) have become even more complicated and complex than before. The purpose of this introduction to biomedical MRI and MRS is to give the readers a basic knowledge that will make it possible for them to pursue studies of their own and to cope with some of the most common problems such as image artifacts or patient questions concerning possible hazards of magnetic resonance. (orig./MG) With 99 figs., 11 tabs

  15. Controlling interactions between highly magnetic atoms with Feshbach resonances.

    Science.gov (United States)

    Kotochigova, Svetlana

    2014-09-01

    This paper reviews current experimental and theoretical progress in the study of dipolar quantum gases of ground and meta-stable atoms with a large magnetic moment. We emphasize the anisotropic nature of Feshbach resonances due to coupling to fast-rotating resonant molecular states in ultracold s-wave collisions between magnetic atoms in external magnetic fields. The dramatic differences in the distribution of resonances of magnetic (7)S3 chromium and magnetic lanthanide atoms with a submerged 4f shell and non-zero electron angular momentum is analyzed. We focus on dysprosium and erbium as important experimental advances have been recently made to cool and create quantum-degenerate gases for these atoms. Finally, we describe progress in locating resonances in collisions of meta-stable magnetic atoms in electronic P-states with ground-state atoms, where an interplay between collisional anisotropies and spin-orbit coupling exists.

  16. Resonant Magnetization Tunneling in Molecular Magnets: Where is the Inhomogeneous Broadening?

    Science.gov (United States)

    Friedman, Jonathan R.; Sarachik, M. P.

    1998-03-01

    Since the discovery(J. R. Friedman, et al., Phys. Rev. Lett. 76), 3830 (1996) of resonant magnetization tunneling in the molecular magnet Mn_12 there has been intense research into the underlying mechanism of tunneling. Most current theories( V. Dobrovitski and A. Zvezdin, Europhys. Lett. 38), 377 (1997); L. Gunther, Europhys. Lett. 39, 1 (1997); D Garanin and E. Chudnovsky, Phys. Rev. B 56, 11102 (1997). suggest that a local internal (hyperfine or dipole) field transverse to the easy magnetization axis induces tunneling. These theories predict a resonance width orders of magnitude smaller than that actually observed. This discrepancy is attributed to inhomogeneous broadening of the resonance by the random internal fields. We present a detailed study of the tunnel resonance lineshape and show that it is Lorentzian, suggesting it has a deeper physical origin. Since the hyperfine fields are believed to be comparable to the observed width, it is surprising that there is no Gaussian broadening.

  17. 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.)

  18. Capsular contracture and possible implant rupture: is magnetic resonance imaging useful?

    Science.gov (United States)

    Paetau, Alyssa A; McLaughlin, Sarah A; McNeil, Rebecca B; Sternberg, Erez; TerKonda, Sarvam P; Waldorf, James C; Perdikis, Galen

    2010-03-01

    Currently, magnetic resonance imaging is considered the accepted standard to evaluate breast implant integrity. To evaluate its utility in diagnosing ruptured silicone implants in the setting of capsular contracture and to correlate the preoperative assessment of implant integrity with or without magnetic resonance imaging with operative findings, 319 capsulectomies (171 patients with capsular contractures) were retrospectively reviewed. Preoperative magnetic resonance imaging was done on 160 implants, whereas the remaining 159 were evaluated using only physical examination and/or mammography. Postoperative results were analyzed to determine the sensitivity, specificity, and accuracy of preoperative magnetic resonance imaging in comparison with clinical and/or mammography evaluation alone. Although occasionally valuable, overall, preoperative magnetic resonance imaging was no more accurate than clinical evaluation with or without mammography in predicting implant status: magnetic resonance imaging 124 of 160 (78 percent) and clinical 121 of 159 (76 percent; p = 0.77). In the setting of capsular contracture, physical examination with or without mammogram is as accurate as magnetic resonance imaging in determining implant integrity. Although magnetic resonance imaging is a sensitive diagnostic tool, in symptomatic patients with capsular contracture, it cannot be viewed as infallible.

  19. SQUID-detected magnetic resonance imaging in microtesla magnetic fields

    International Nuclear Information System (INIS)

    McDermott, Robert; Kelso, Nathan; Lee, SeungKyun; Moessle, Michael; Mueck, Michael; Myers, Whittier; Haken, Bernard ten; Seton, H.C.; Trabesinger, Andreas H.; Pines, Alex; Clarke, John

    2003-01-01

    We describe studies of nuclear magnetic resonance (NMR) spectroscopy and magnetic resonance imaging (MRI) of liquid samples at room temperature in microtesla magnetic fields. The nuclear spins are prepolarized in a strong transient field. The magnetic signals generated by the precessing spins, which range in frequency from tens of Hz to several kHz, are detected by a low-transition temperature dc SQUID (Superconducting QUantum Interference Device) coupled to an untuned, superconducting flux transformer configured as an axial gradiometer. The combination of prepolarization and frequency-independent detector sensitivity results in a high signal-to-noise ratio and high spectral resolution (∼1 Hz) even in grossly inhomogeneous magnetic fields. In the NMR experiments, the high spectral resolution enables us to detect the 10-Hz splitting of the spectrum of protons due to their scalar coupling to a 31P nucleus. Furthermore, the broadband detection scheme combined with a non-resonant field-reversal spin echo allows the simultaneous observation of signals from protons and 31P nuclei, even though their NMR resonance frequencies differ by a factor of 2.5. We extend our methodology to MRI in microtesla fields, where the high spectral resolution translates into high spatial resolution. We demonstrate two-dimensional images of a mineral oil phantom and slices of peppers, with a spatial resolution of about 1 mm. We also image an intact pepper using slice selection, again with 1-mm resolution. In further experiments we demonstrate T1-contrast imaging of a water phantom, some parts of which were doped with a paramagnetic salt to reduce the longitudinal relaxation time T1. Possible applications of this MRI technique include screening for tumors and integration with existing multichannel SQUID systems for brain imaging

  20. Magnetic resonance of field-frozen and zero-field-frozen magnetic fluids

    International Nuclear Information System (INIS)

    Pereira, A.R.; Pelegrini, F.; Neto, K. Skeff; Buske, N.; Morais, P.C.

    2004-01-01

    In this study magnetic resonance was used to investigate magnetic fluid samples frozen under zero and non-zero (15 kG) external fields. The magnetite-based sample containing 2x10 17 particle/cm 3 was investigated from 100 to 400 K. Analysis of the temperature dependence of the resonance field revealed bigger magnetic structures in the frozen state than in the liquid phase. Also, differences in the mesoscopic organization in the frozen state may explain the data obtained from samples frozen under zero and non-zero fields

  1. Magnetic resonance, a phenomenon with a great potential in medicine, but with a complex physical background – Part 2: The basics of magnetic resonance

    Directory of Open Access Journals (Sweden)

    Bojan Božič

    2014-01-01

    Full Text Available Magnetic resonance imaging is a very complex diagnostic technique. Therefore, both practical experiences and theoretical understanding is needed for effective diagnostics. It is therefore important that physicians are sufficiently familiar with the basic physical principles of magnetic resonance. In the interpretation of physical concepts, we will rely both on the classical as well as on the quantum-mechanical view of the signal formation in magnetic resonance, which are to some extent complementary. The signal appearance in magnetic resonance imaging will be discussed. A special emphasis will be put on the role of the resonance frequency and the pulse sequences. Furthermore, the spin echo as one of the most used classical signal sequences in diagnostic investigations will be described.

  2. High-resolution 3T Magnetic Resonance Imaging of the Triangular Fibrocartilage Complex in Chinese Wrists: Correlation with Cross-sectional Anatomy.

    Science.gov (United States)

    Zhan, Hui-Li; Li, Wen-Ting; Bai, Rong-Jie; Wang, Nai-Li; Qian, Zhan-Hua; Ye, Wei; Yin, Yu-Ming

    2017-04-05

    The injury of the triangular fibrocartilage complex (TFCC) is a common cause of ulnar-sided wrist pain. The aim of this study was to investigate if the high-resolution 3T magnetic resonance imaging (MRI) could demonstrate the detailed complex anatomy of TFCC in Chinese. Fourteen Chinese cadaveric wrists (from four men and three women; age range at death from 30 to 60 years; mean age at 46 years) and forty healthy Chinese wrists (from 20 healthy volunteers, male/female: 10/10; age range from 21 to 53 years with a mean age of 32 years) in Beijing Jishuitan Hospital from March 2014 to March 2016 were included in this study. All cadavers and volunteers had magnetic resonance (MR) examination of the wrist with coronal T1-weighted and proton density-weighted imaging with fat suppression in three planes, respectively. MR arthrography (MRAr) was performed on one of the cadaveric wrists. Subsequently, all 14 cadaveric wrists were sliced into 2 mm thick slab with band saw (six in coronal plane, four in sagittal plane, and four in axial plane). The MRI features of normal TFCC were analyzed in these specimens and forty healthy wrists. Triangular fibrocartilage, the ulnar collateral ligament, and the meniscal homolog could be best observed on images in coronal plane. The palmar and dorsal radioulnar ligaments were best evaluated in transverse plane. The ulnotriquetral and ulnolunate ligaments were best visualized in sagittal plane. The latter two structures and the volar and dorsal capsules were better demonstrated on MRAr. High-resolution 3T MRI is capable to show the detailed complex anatomy of the TFCC and can provide valuable information for the clinical diagnosis in Chinese.

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

    Energy Technology Data Exchange (ETDEWEB)

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

    1986-09-01

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

  4. Quantum transport in coupled resonators enclosed synthetic magnetic flux

    International Nuclear Information System (INIS)

    Jin, L.

    2016-01-01

    Quantum transport properties are instrumental to understanding quantum coherent transport processes. Potential applications of quantum transport are widespread, in areas ranging from quantum information science to quantum engineering, and not restricted to quantum state transfer, control and manipulation. Here, we study light transport in a ring array of coupled resonators enclosed synthetic magnetic flux. The ring configuration, with an arbitrary number of resonators embedded, forms a two-arm Aharonov–Bohm interferometer. The influence of magnetic flux on light transport is investigated. Tuning the magnetic flux can lead to resonant transmission, while half-integer magnetic flux quantum leads to completely destructive interference and transmission zeros in an interferometer with two equal arms. -- Highlights: •The light transport is investigated through ring array of coupled resonators enclosed synthetic magnetic field. •Aharonov–Bohm ring interferometer of arbitrary configuration is investigated. •The half-integer magnetic flux quantum leads to destructive interference and transmission zeros for two-arm at equal length. •Complete transmission is available via tuning synthetic magnetic flux.

  5. Nuclear magnetic resonance scattering

    International Nuclear Information System (INIS)

    Young, I.R.

    1985-01-01

    A nuclear magnetic resonance apparatus is described including a magnet system which is capable of providing a steady magnetic field along an axis, and is constructed so as to define a plurality of regions along the axis in each of which the field is substantially homogeneous so that in each region an imaging operation may be separately carried out. Iron shields increase the field homogeneity. In use, each patient lies on a wheeled trolley which is provided with magnetic field gradient coils and an RF coil system, some of the coils being movable to facilitate positioning of the patient, and there are terminals for connection to a common computing and control facility. (author)

  6. 21 CFR 892.1000 - Magnetic resonance diagnostic device.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Magnetic resonance diagnostic device. 892.1000 Section 892.1000 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES RADIOLOGY DEVICES Diagnostic Devices § 892.1000 Magnetic resonance diagnostic...

  7. Concepts and indications of abdominal magnetic resonance

    International Nuclear Information System (INIS)

    Murillo Viera, Wendy

    2012-01-01

    A literature review and conceptualization was performed of the main indications of magnetic resonance studies of the abdomen and the characteristic findings for each sequence, according to organ and pathology. The radiologist has had in mind main indications for magnetic resonance studies of the abdomen, with the purpose to guide the clinician in the choice of imaging modality that works best for the patient at diagnosis [es

  8. Magnetic resonance imaging in the evaluation of periosteal reactions

    Energy Technology Data Exchange (ETDEWEB)

    Nogueira-Barbosa, Marcello Henrique; Trad, Clovis Simao; Muglia, Valdair Francisco; Elias Junior, Jorge; Simao, Marcelo Novelino, E-mail: marcello@fmrp.usp.b [Universidade de Sao Paulo (USP), Ribeirao Preto, SP (Brazil). Faculdade de Medicina. Centro de Ciencias das Imagens e Fisica Medica; Sa, Jose Luiz de [Universidade de Sao Paulo (USP), Ribeirao Preto, SP (Brazil). Faculdade de Medicina. Hospital das Clinicas; Oliveira, Rodrigo Cecilio Vieira de [Clinica de Diagnostico por Imagem Tomoson, Aracatuba, SP (Brazil); Engel, Edgard Eduard [Universidade de Sao Paulo (USP), Ribeirao Preto, SP (Brazil). Faculdade de Medicina. Dept. de Biomecanica, Medicina e Reabilitacao do Aparelho Locomotor

    2010-07-15

    The objective of the present essay was to encourage a careful evaluation of periosteal reactions on magnetic resonance images. The initial approach to bone lesions is made by conventional radiography and, based on the imaging findings, periosteal reactions are classified into classical subtypes. Although magnetic resonance imaging is considered as the gold standard for local staging of bone tumors, the utilization of such method in the study of periosteal reactions related to focal bone lesions has been poorly emphasized, with relatively few studies approaching this subject. The literature review revealed a study describing an experimental animal model of osteomyelitis suggesting that magnetic resonance imaging is superior to other imaging methods in the early identification of periosteal reactions. Another study has suggested a good correlation between conventional radiography and magnetic resonance imaging in the identification and classification of periosteal reactions in cases of osteosarcoma. The present essay illustrates cases of periosteal reactions observed at magnetic resonance imaging in correlation with findings of conventional radiography or other imaging methods. (author)

  9. Magnetic resonance imaging in the evaluation of periosteal reactions

    International Nuclear Information System (INIS)

    Nogueira-Barbosa, Marcello Henrique; Trad, Clovis Simao; Muglia, Valdair Francisco; Elias Junior, Jorge; Simao, Marcelo Novelino; Engel, Edgard Eduard

    2010-01-01

    The objective of the present essay was to encourage a careful evaluation of periosteal reactions on magnetic resonance images. The initial approach to bone lesions is made by conventional radiography and, based on the imaging findings, periosteal reactions are classified into classical subtypes. Although magnetic resonance imaging is considered as the gold standard for local staging of bone tumors, the utilization of such method in the study of periosteal reactions related to focal bone lesions has been poorly emphasized, with relatively few studies approaching this subject. The literature review revealed a study describing an experimental animal model of osteomyelitis suggesting that magnetic resonance imaging is superior to other imaging methods in the early identification of periosteal reactions. Another study has suggested a good correlation between conventional radiography and magnetic resonance imaging in the identification and classification of periosteal reactions in cases of osteosarcoma. The present essay illustrates cases of periosteal reactions observed at magnetic resonance imaging in correlation with findings of conventional radiography or other imaging methods. (author)

  10. Nuclear resonance apparatus including means for rotating a magnetic field

    International Nuclear Information System (INIS)

    Sugimoto, H.

    1983-01-01

    A nuclear magnetic resonance apparatus including magnet apparatus for generating a homogeneous static magnetic field between its magnetic poles, shims of a magnetic substance mounted on the magnetic poles to apply a first gradient magnetic field intensity distribution in a direction orthogonal as to the direction of line of magnetic force of the static magnetic field, gradient magnetic field generating electromagnetic apparatus for generating a second gradient magnetic field having a gradient magnetic field intensity distribution in superimposition with the static magnetic field and for changing the magnetic field gradient of the first gradient magnetic field, an oscillator for generating an oscillating output having a frequency corresponding to the nuclear magnetic resonance condition of an atomic nucleus to be measured, a coil wound around a body to be examined for applying the output of said oscillator as electromagnetic waves upon the body, a receiver for detecting the nuclear magnetic resonance signals received by the coil, a gradient magnetic field controller making a magnetic field line equivalent to the combined gradient magnetic fields and for rotating the line along the section of the body to be examined by controlling said gradient magnetic field generating electromagnetic apparatus and devices for recording the nuclear magnetic resonance signals, for reconstructing the concentration distribution of the specific atomic nuclei in the section of the body, and a display unit for depicting the result of reconstruction

  11. Resonance magnetic x-ray scattering study of erbium

    DEFF Research Database (Denmark)

    Sanyal, M.K.; Gibbs, D.; Bohr, J.

    1994-01-01

    The magnetic phases of erbium have been studied by resonance x-ray-scattering techniques. When the incident x-ray energy is tuned near the L(III) absorption edge, large resonant enhancements of the magnetic scattering are observed above 18 K. We have measured the energy and polarization dependence...... of this magnetic scattering and analyzed it using a simple model based on electric dipole and quadrupole transitions among atomic orbitals. The line shapes can be fitted to a magnetic structure combining both c-axis-modulated and basal-plane components. Below 18 K, we have observed unusual behavior of the magnetic...

  12. 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.)

  13. Magnetic Resonance Cholangiopancreatography (MRCP)

    Science.gov (United States)

    ... radio waves and a computer to evaluate the liver, gallbladder, bile ducts, pancreas and pancreatic duct for disease. It is ... of the hepatobiliary and pancreatic systems, including the liver, gallbladder, bile ducts, pancreas and pancreatic duct . Magnetic resonance imaging (MRI) ...

  14. Science Drivers and Technical Challenges for Advanced Magnetic Resonance

    Energy Technology Data Exchange (ETDEWEB)

    Mueller, Karl T.; Pruski, Marek; Washton, Nancy M.; Lipton, Andrew S.

    2013-03-07

    This report recaps the "Science Drivers and Technical Challenges for Advanced Magnetic Resonance" workshop, held in late 2011. This exploratory workshop's goal was to discuss and address challenges for the next generation of magnetic resonance experimentation. During the workshop, participants from throughout the world outlined the science drivers and instrumentation demands for high-field dynamic nuclear polarization (DNP) and associated magnetic resonance techniques, discussed barriers to their advancement, and deliberated the path forward for significant and impactful advances in the field.

  15. Frequency-domain analysis of resonant-type ring magnet power supplies

    International Nuclear Information System (INIS)

    Kim, J.M.S.; Reiniger, K.W.

    1993-01-01

    For fast-cycling synchrotrons, resonant-type ring magnet power supplies are commonly used to provide a dc-biased ac excitation for the ring magnets. Up to the present, this power supply system has been analyzed using simplified analytical approximation, namely assuming the resonant frequency of the ring magnet network is fixed and equal to the accelerator frequency. This paper presents a frequency-domain analysis technique for a more accurate analysis of resonant-type ring magnet power supplies. This approach identifies that, with the variation of the resonant frequency, the operating conditions of the power supply changes quite dramatically because of the high Q value of the resonant network. The analytical results are verified, using both experimental results and simulation results

  16. Resonant cell of a double nuclear electron resonance spectrometer for performance in a 120-350 Gs magnetic field

    International Nuclear Information System (INIS)

    Baldin, V.I.; Stepanov, A.P.

    1976-01-01

    Spectrometer double-frequency resonance cell construction of a double nuclear electron resonance for operation in 120-350 Gs magnetic fields is described. The cell has been developed from a special decimeter resonator with a concentrated capacitance. The electric and magnetic components of a high frequency field are efficiently divided in the separator. Therefore, the insertion of a measuring coil and a sample in the maximum of the magnetic component of the field does not practically affect the distribution and parameters of the high-frequency field. The double-frequency resonance cell proposed provides for a higher accuracy of measuring amplifications of the nuclear magnetic resonance signals when there is the overhauzer effect for 120-350 Gs magnetic fields

  17. Can magnetic resonance imaging differentiate undifferentiated arthritis?

    DEFF Research Database (Denmark)

    Østergaard, Mikkel; Duer, Anne; Hørslev-Petersen, K

    2005-01-01

    A high sensitivity for the detection of inflammatory and destructive changes in inflammatory joint diseases makes magnetic resonance imaging potentially useful for assigning specific diagnoses, such as rheumatoid arthritis and psoriatic arthritis in arthritides, that remain undifferentiated after...... conventional clinical, biochemical and radiographic examinations. With recent data as the starting point, the present paper describes the current knowledge on magnetic resonance imaging in the differential diagnosis of undifferentiated arthritis....

  18. Effect of resonance line shape on precision measurements of nuclear magnetic resonance shifts

    International Nuclear Information System (INIS)

    Kachurin, A.M.; Smelyanskij, A.Ya.

    1986-01-01

    Effect of resonance line shape on the systematic error of precision measurements of nuclear magnetic resonance (NMR) shifts of high resolution (on the center of NMR dispersion line) is analysed. Effect of the device resonance line form-function asymmetry is evaluated; the form-function is determined by configuration of the spectrometer magnetic field and enters the convolution, which describes the resonance line form. It is shown that with the increase of the relaxation line width the form-function effect on the measurement error yields to zero. The form-function effect on measurements and correction of a phase angle of NMR detection is evaluated. The method of semiquantitative evaluation of resonance line and NMR spectrometer parameters, guaranteeing the systematic error of the given infinitesimal, is presented

  19. Magnetic resonance imaging of infectious myositis

    Energy Technology Data Exchange (ETDEWEB)

    Yun, Ji Young; Kim, Jee Young; Kim, Sang Heum; Jung, Youn Ju; Cha, Eun Suk; Park, Joung Mi; Park, Young Ha [The Catholic Univ., College of Medicine, Suwon (Korea, Republic of)

    1998-09-01

    To describe the findings of magnetic resonance imaging in infectious myositis and to determine their value for differentiation between ruberculous and bacterial myositis. Magnetic resonance images of ten proven cases of infectious myositis (five tuberculous and five bacterial) were retrospectively reviewed in the light of clinical and laboratory findings. On the basis of magnetic resonance images, signal intensity of the mass, the presence or absence of an abscess, signal intensity of the peripheral wall, patterns of contrast enhancement, and associated findings were evaluated. Compared with those of bacterial myositis, the symptoms of tuberculous myositis lasted longer but there were no difinite local inflammatory signs. In three of five cases of bacterial myositis there were specific medical records;trauma in two cases and systemic lupus erythematosus in one. All tuberculous myositis cases involved a single muscle, but bacterial myositis affected multipe muscles in three cases(60%). All but one case showed a mass in the involved muscles. In one bacterial case, there was diffuse swelling in the involved muscle. On T1-weighted images, eight infectious cases showed low signal intensity;two, of the bactrerial type, showed subtle increased signal intensity. all cases demonstrated high signal intensity on t2-weighted images. The signal intensity of peripheral wall was slightly increased on T1-weighted images, but low on T2-weighted. In four cases there was associated cellulitis, and in one case each, adjacent joint effusion and deep vein thrombosis were seen. After gadolinium infusion, peripheral rim enhancement was noted in nine cases and heterogeneous enhancement in one. After magnetic resonance imaging of infectious myositis, the characteristic finding was an abscessed lesion, with the peripheral wall showing high signal intensity on T1-weighted images and low signal intensity on T2 weighted. Although we found it difficult to differentiate bacterial from tuberculous

  20. Magnetic resonance imaging of infectious myositis

    International Nuclear Information System (INIS)

    Yun, Ji Young; Kim, Jee Young; Kim, Sang Heum; Jung, Youn Ju; Cha, Eun Suk; Park, Joung Mi; Park, Young Ha

    1998-01-01

    To describe the findings of magnetic resonance imaging in infectious myositis and to determine their value for differentiation between ruberculous and bacterial myositis. Magnetic resonance images of ten proven cases of infectious myositis (five tuberculous and five bacterial) were retrospectively reviewed in the light of clinical and laboratory findings. On the basis of magnetic resonance images, signal intensity of the mass, the presence or absence of an abscess, signal intensity of the peripheral wall, patterns of contrast enhancement, and associated findings were evaluated. Compared with those of bacterial myositis, the symptoms of tuberculous myositis lasted longer but there were no difinite local inflammatory signs. In three of five cases of bacterial myositis there were specific medical records;trauma in two cases and systemic lupus erythematosus in one. All tuberculous myositis cases involved a single muscle, but bacterial myositis affected multipe muscles in three cases(60%). All but one case showed a mass in the involved muscles. In one bacterial case, there was diffuse swelling in the involved muscle. On T1-weighted images, eight infectious cases showed low signal intensity;two, of the bactrerial type, showed subtle increased signal intensity. all cases demonstrated high signal intensity on t2-weighted images. The signal intensity of peripheral wall was slightly increased on T1-weighted images, but low on T2-weighted. In four cases there was associated cellulitis, and in one case each, adjacent joint effusion and deep vein thrombosis were seen. After gadolinium infusion, peripheral rim enhancement was noted in nine cases and heterogeneous enhancement in one. After magnetic resonance imaging of infectious myositis, the characteristic finding was an abscessed lesion, with the peripheral wall showing high signal intensity on T1-weighted images and low signal intensity on T2 weighted. Although we found it difficult to differentiate bacterial from tuberculous

  1. Molecular structure and motion in zero field magnetic resonance

    International Nuclear Information System (INIS)

    Jarvie, T.P.

    1989-10-01

    Zero field magnetic resonance is well suited for the determination of molecular structure and the study of motion in disordered materials. Experiments performed in zero applied magnetic field avoid the anisotropic broadening in high field nuclear magnetic resonance (NMR) experiments. As a result, molecular structure and subtle effects of motion are more readily observed

  2. Diagnostic imaging of psoriatic arthritis. Part II: magnetic resonance imaging and ultrasonography

    Directory of Open Access Journals (Sweden)

    Iwona Sudoł-Szopińska

    2016-06-01

    Full Text Available Plain radiography reveals specific, yet late changes of advanced psoriatic arthritis. Early inflammatory changes are seen both on magnetic resonance imaging and ultrasound within peripheral joints (arthritis, synovitis, tendons sheaths (tenosynovitis, tendovaginitis and entheses (enthesitis, enthesopathy. In addition, magnetic resonance imaging enables the assessment of inflammatory features in the sacroiliac joints (sacroiliitis, and the spine (spondylitis. In this article, we review current opinions on the diagnostics of some selective, and distinctive features of psoriatic arthritis concerning magnetic resonance imaging and ultrasound and present some hypotheses on psoriatic arthritis etiopathogenesis, which have been studied with the use of magnetic resonance imaging. The following elements of the psoriatic arthritis are discussed: enthesitis, extracapsular inflammation, dactylitis, distal interphalangeal joint and nail disease, and the ability of magnetic resonance imaging to differentiate undifferentiated arthritis, the value of whole-body magnetic resonance imaging and dynamic contrast-enhanced magnetic resonance imaging.

  3. Magnetic resonance spectroscopy as a diagnostic modality for carcinoma thyroid

    International Nuclear Information System (INIS)

    Gupta, Nikhil; Kakar, Arun K.; Chowdhury, Veena; Gulati, Praveen; Shankar, L. Ravi; Vindal, Anubhav

    2007-01-01

    Aim: The aim of this study was to observe the findings of magnetic resonance spectroscopy of solitary thyroid nodules and its correlation with histopathology. Materials and methods: In this study, magnetic resonance spectroscopy was carried out on 26 patients having solitary thyroid nodules. Magnetic resonance spectroscopy (MRS) was performed on a 1.5 T super conductive system with gradient strength of 33 mTs. Fine needle aspiration cytology was done after MRS. All 26 patients underwent surgery either because of cytopathologically proven malignancy or because of cosmetic reasons. Findings of magnetic resonance spectroscopy were compared with histopathology of thyroid specimens. Results and conclusion: It was seen that presence or absence of choline peak correlates very well with presence or absence of malignant foci with in the nodule (sensitivity = 100%; specificity = 88.88%). These results indicate that magnetic resonance spectroscopy may prove to be an useful diagnostic modality for carcinoma thyroid

  4. [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.

  5. Magnetic resonance, especially spin echo, in spinor Bose-Einstein condensates

    International Nuclear Information System (INIS)

    Yasunaga, Masashi; Tsubota, Makoto

    2009-01-01

    Magnetic resonance, especially NMR and ESR, has been studied in magnetic materials for a long time, having been used in various fields. Spin echo is typical phenomenon in magnetic resonance. The magnetic resonance should be applied to spinor Bose-Einstein condensates (BECs). We numerically study spin echo of a spinor BEC in a gradient magnetic field by calculating the spin-1 two-dimensional Gross-Pitaevskii equations, obtaining the recovery of the signal of the spins, which is called spin echo. We will discuss the relation between the spin echo and the Stern-Gelrach separation in the system.

  6. Magnetic Resonance Imaging Studies of Postpartum Depression: An Overview

    Directory of Open Access Journals (Sweden)

    Marco Fiorelli

    2015-01-01

    Full Text Available Postpartum depression is a frequent and disabling condition whose pathophysiology is still unclear. In recent years, the study of the neural correlates of mental disorders has been increasingly approached using magnetic resonance techniques. In this review we synthesize the results from studies on postpartum depression in the context of structural, functional, and spectroscopic magnetic resonance studies of major depression as a whole. Compared to the relative wealth of data available for major depression, magnetic resonance studies of postpartum depression are limited in number and design. A systematic literature search yielded only eleven studies conducted on about one hundred mothers with postpartum depression overall. Brain magnetic resonance findings in postpartum depression appear to replicate those obtained in major depression, with minor deviations that are not sufficient to delineate a distinct neurobiological profile for this condition, due to the small samples used and the lack of direct comparisons with subjects with major depression. However, it seems reasonable to expect that studies conducted in larger populations, and using a larger variety of brain magnetic resonance techniques than has been done so far, might allow for the identification of neuroimaging signatures for postpartum depression.

  7. Quantitative magnetic resonance micro-imaging methods for pharmaceutical research.

    Science.gov (United States)

    Mantle, M D

    2011-09-30

    The use of magnetic resonance imaging (MRI) as a tool in pharmaceutical research is now well established and the current literature covers a multitude of different pharmaceutically relevant research areas. This review focuses on the use of quantitative magnetic resonance micro-imaging techniques and how they have been exploited to extract information that is of direct relevance to the pharmaceutical industry. The article is divided into two main areas. The first half outlines the theoretical aspects of magnetic resonance and deals with basic magnetic resonance theory, the effects of nuclear spin-lattice (T(1)), spin-spin (T(2)) relaxation and molecular diffusion upon image quantitation, and discusses the applications of rapid magnetic resonance imaging techniques. In addition to the theory, the review aims to provide some practical guidelines for the pharmaceutical researcher with an interest in MRI as to which MRI pulse sequences/protocols should be used and when. The second half of the article reviews the recent advances and developments that have appeared in the literature concerning the use of quantitative micro-imaging methods to pharmaceutically relevant research. Copyright © 2010 Elsevier B.V. All rights reserved.

  8. Comparative analysis of nuclear magnetic resonance well logging and nuclear magnetic resonance mud logging

    International Nuclear Information System (INIS)

    Yuan Zugui

    2008-01-01

    The hydrogen atoms in oil and water are able to resonate and generate signals in the magnetic field, which is used by the NMR (nuclear magnetic resonance) technology in petroleum engineering to research and evaluate rock characteristics. NMR well logging was used to measure the physical property parameters of the strata in well bore, whereas NMR mud logging was used to analyze (while drilling) the physical property parameters of cores, cuttings and sidewall coring samples on surface (drilling site). Based on the comparative analysis of the porosity and permeability parameters obtained by NMR well logging and those from analysis of the cores, cuttings and sidewall coring samples by NMR mud logging in the same depth of 13 wells, these two methods are of certain difference, but their integral tendency is relatively good. (authors)

  9. Magnetic resonance tomography for trauma of the cervical spine

    International Nuclear Information System (INIS)

    Meydam, K.; Sehlen, S.; Schlenkhoff, D.; Kiricuta, J.C.; Beyer, H.K.

    1986-01-01

    Twenty patients who had suffered spinal trauma were examined by magnetic resonance tomography. Fifteen patients with first degree trauma in Erdmann's classification showed no abnormality. Magnetic resonance tomography of the cervical spine appears to be a suitable method for investigating patients with whiplash injuries. It is indicated following severe flexion injuries with subluxations and neurological symptoms, since it is the only method that can demonstrate the spinal cord directly and completely and show the extent of cord compression. For patients with thoracic trauma and rapidly developing neurological symptoms, magnetic resonance tomography is ideal for showing post-traumatic syringomyelia. Magnetic resonance tomography following whiplash injuries is recommended if plain films of the cervical spine show any abnormalities, as well as for the investigation of acute or sub-acute neurological abnormalities. The various findings are discussed. (orig.) [de

  10. Magnetic resonance tomography for trauma of the cervical spine

    Energy Technology Data Exchange (ETDEWEB)

    Meydam, K.; Sehlen, S.; Schlenkhoff, D.; Kiricuta, J.C.; Beyer, H.K.

    1986-12-01

    Twenty patients who had suffered spinal trauma were examined by magnetic resonance tomography. Fifteen patients with first degree trauma in Erdmann's classification showed no abnormality. Magnetic resonance tomography of the cervical spine appears to be a suitable method for investigating patients with whiplash injuries. It is indicated following severe flexion injuries with subluxations and neurological symptoms, since it is the only method that can demonstrate the spinal cord directly and completely and show the extent of cord compression. For patients with thoracic trauma and rapidly developing neurological symptoms, magnetic resonance tomography is ideal for showing post-traumatic syringomyelia. Magnetic resonance tomography following whiplash injuries is recommended if plain films of the cervical spine show any abnormalities, as well as for the investigation of acute or sub-acute neurological abnormalities. The various findings are discussed.

  11. Normal perinatal and paediatric postmortem magnetic resonance imaging appearances

    Energy Technology Data Exchange (ETDEWEB)

    Arthurs, Owen J. [Department of Radiology, Great Ormond Street Hospital for Children NHS Foundation Trust, London (United Kingdom); UCL Institute of Child Health, London (United Kingdom); Barber, Joy L. [Department of Radiology, Great Ormond Street Hospital for Children NHS Foundation Trust, London (United Kingdom); Taylor, Andrew M. [Cardiorespiratory Division, Great Ormond Street Hospital for Children NHS Foundation Trust, London (United Kingdom); UCL Institute of Cardiovascular Science, Centre for Cardiovascular Imaging, London (United Kingdom); Sebire, Neil J. [UCL Institute of Child Health, London (United Kingdom); Department of Histopathology, Great Ormond Street Hospital for Children NHS Foundation Trust, London (United Kingdom)

    2015-04-01

    As postmortem imaging becomes more widely used following perinatal and paediatric deaths, the correct interpretation of images becomes imperative, particularly given the increased use of postmortem magnetic resonance imaging. Many pathological processes may have similar appearances in life and following death. A thorough knowledge of normal postmortem changes is therefore required within postmortem magnetic resonance imaging to ensure that these are not mistakenly interpreted as significant pathology. Similarly, some changes that are interpreted as pathological if they occur during life may be artefacts on postmortem magnetic resonance imaging that are of limited significance. This review serves to illustrate briefly those postmortem magnetic resonance imaging changes as part of the normal changes after death in fetuses and children, and highlight imaging findings that may confuse or mislead an observer to identifying pathology where none is present. (orig.)

  12. Topical questions in magnetic resonance imaging

    International Nuclear Information System (INIS)

    Andrew, E.R.; Florida Univ., Gainesville, FL; Florida Univ., Gainesville, FL

    1989-01-01

    This paper examines a number of practical questions concerning magnetic resonance imaging. These include the choice of operating magnetic field strength, the problem of siting and screening, a procedure for securing precise slice selection and the use of paramagnetic contrast agents. (author). 5 refs

  13. 'Blocking' effects in magnetic resonance? The ferromagnetic nanowires case

    International Nuclear Information System (INIS)

    Ramos, C.A.; De Biasi, E.; Zysler, R.D.; Vassallo Brigneti, E.; Vazquez, M.

    2007-01-01

    We present magnetic resonance results obtained at L, X, and Q bands (1.2, 9.4 and 34GHz, respectively) on ferromagnetic nanowires with a hysteresis cycle characterized by a remanent magnetization M r /M s ∼0.92 and a coercive field H c =1.0kOe. The hysteretic response of the ferromagnetic resonance spectra is discussed in terms of independent contributions of the nanowires aligned along and opposite to the applied field. We will discuss the implications of this study on the magnetic resonance in nanoparticles and other systems with large anisotropy

  14. Recent trends in high spin sensitivity magnetic resonance

    Science.gov (United States)

    Blank, Aharon; Twig, Ygal; Ishay, Yakir

    2017-07-01

    Magnetic resonance is a very powerful methodology that has been employed successfully in many applications for about 70 years now, resulting in a wealth of scientific, technological, and diagnostic data. Despite its many advantages, one major drawback of magnetic resonance is its relatively poor sensitivity and, as a consequence, its bad spatial resolution when examining heterogeneous samples. Contemporary science and technology often make use of very small amounts of material and examine heterogeneity on a very small length scale, both of which are well beyond the current capabilities of conventional magnetic resonance. It is therefore very important to significantly improve both the sensitivity and the spatial resolution of magnetic resonance techniques. The quest for higher sensitivity led in recent years to the development of many alternative detection techniques that seem to rival and challenge the conventional ;old-fashioned; induction-detection approach. The aim of this manuscript is to briefly review recent advances in the field, and to provide a quantitative as well as qualitative comparison between various detection methods with an eye to future potential advances and developments. We first offer a common definition of sensitivity in magnetic resonance to enable proper quantitative comparisons between various detection methods. Following that, up-to-date information about the sensitivity capabilities of the leading recently-developed detection approaches in magnetic resonance is provided, accompanied by a critical comparison between them and induction detection. Our conclusion from this comparison is that induction detection is still indispensable, and as such, it is very important to look for ways to significantly improve it. To do so, we provide expressions for the sensitivity of induction-detection, derived from both classical and quantum mechanics, that identify its main limiting factors. Examples from current literature, as well as a description of

  15. Bayesian estimation of multicomponent relaxation parameters in magnetic resonance fingerprinting.

    Science.gov (United States)

    McGivney, Debra; Deshmane, Anagha; Jiang, Yun; Ma, Dan; Badve, Chaitra; Sloan, Andrew; Gulani, Vikas; Griswold, Mark

    2018-07-01

    To estimate multiple components within a single voxel in magnetic resonance fingerprinting when the number and types of tissues comprising the voxel are not known a priori. Multiple tissue components within a single voxel are potentially separable with magnetic resonance fingerprinting as a result of differences in signal evolutions of each component. The Bayesian framework for inverse problems provides a natural and flexible setting for solving this problem when the tissue composition per voxel is unknown. Assuming that only a few entries from the dictionary contribute to a mixed signal, sparsity-promoting priors can be placed upon the solution. An iterative algorithm is applied to compute the maximum a posteriori estimator of the posterior probability density to determine the magnetic resonance fingerprinting dictionary entries that contribute most significantly to mixed or pure voxels. Simulation results show that the algorithm is robust in finding the component tissues of mixed voxels. Preliminary in vivo data confirm this result, and show good agreement in voxels containing pure tissue. The Bayesian framework and algorithm shown provide accurate solutions for the partial-volume problem in magnetic resonance fingerprinting. The flexibility of the method will allow further study into different priors and hyperpriors that can be applied in the model. Magn Reson Med 80:159-170, 2018. © 2017 International Society for Magnetic Resonance in Medicine. © 2017 International Society for Magnetic Resonance in Medicine.

  16. Low field magnetic resonance experiments in superfluid 3He--A

    International Nuclear Information System (INIS)

    Gully, W.J. Jr.

    1976-01-01

    Measurements of the longitudinal and transverse nuclear magnetic resonance signals have been made on the A phase of liquid 3 He. They were performed on a sample of 3 He self-cooled by the Pomeranchuk effect to the critical temperature of the superfluid at 2.7 m 0 K. The longitudinal resonance is a magnetic mode of the liquid excited by radio frequency magnetic fields applied in the direction of the static magnetic field. Frequency profiles of this resonance were indirectly obtained by contour techniques from signals recorded by sweeping the temperature. Its frequency is found to be related to the frequency shift of the transverse resonance in agreement with theoretical predictions for the ABM pairing state. Its linewidth also agrees with theoretical predictions based upon dissipative phenomena peculiar to the superfluid phase. An analysis of the linewidth of the longitudinal resonance yields a value for the quasiparticle collision time. Transverse NMR lines were also studied. In low magnetic fields (20 Oersted) these lines were found to become extremely broad. This is shown to be a manifestation of the same collisional processes that broaden the longitudinal resonance lines. Also, the effects of various textures on the resonance lines are discussed, including the results of an attempt to create a single domain of 3 He with crossed electric and magnetic fields

  17. Nuclear magnetic resonance in ferromagnetic terbium metal

    International Nuclear Information System (INIS)

    Cha, C.L.T.

    1974-01-01

    The magnetic properties of terbium were studied by the method of zero field nuclear magnetic resonance at 1.5 to 4 and 85 to 160 0 K. Two unconventional experimental techniques have been employed: the swept frequency and the swept temperature technique. Near 4 0 K, triplet resonance line structures were found and interpreted in terms of the magnetic domain and wall structures of ferromagnetic terbium. In the higher temperature range, temperature dependence of the resonance frequency and the quadrupole splitting were measured. The former provides a measurement of the temperature dependence of the magnetization M, and it agrees with bulk M measurements as well as the latest spin wave theory of M(T) (Brooks 1968). The latter agrees well with a calculation using a very general single ion density matrix for collective excitations (Callen and Shtrikman 1965). In addition, the small temperature-independent contribution to the electric field gradient at the nucleus due to the lattice and conduction electrons was untangled from the P(T) data. Also an anomalous and unexplained relaxation phenomenon was also observed

  18. Functional Magnetic Resonance Imaging

    Science.gov (United States)

    Voos, Avery; Pelphrey, Kevin

    2013-01-01

    Functional magnetic resonance imaging (fMRI), with its excellent spatial resolution and ability to visualize networks of neuroanatomical structures involved in complex information processing, has become the dominant technique for the study of brain function and its development. The accessibility of in-vivo pediatric brain-imaging techniques…

  19. Moessbauer and magnetic resonance experiments on amorphous iron-silicon films

    International Nuclear Information System (INIS)

    Bansal, C.; Campbell, S.J.; Stewart, A.M.

    1982-01-01

    Moessbauer measurements at room temperature and 4.2 K, and room temperature magnetic resonance measurments on a series of amorphous Fesub(x)Sisub(1-x) thin films (0.23 <= x <= 0.81) are presented. The concentration dependence of the isomer shifts and quadrupole splittings provides information on the nature of the local coordination in these amorphous materials. Analysis of the distributions of magnetic hyperfine splitting combined with the presence of multiple resonance in the magnetic resonance data indiates that magnetoanisotropy plays a dominant role in determining the magnetic behaviour of these films. (orig.)

  20. Magnetic resonance imaging

    International Nuclear Information System (INIS)

    Sigal, R.

    1988-01-01

    This book is an introduction to magnetic resonance imaging (MRI). The basic principles for the interpretation of MR images are developed. The book is divided into five chapters: introduction, tissue, parameters, acquisition parameters, contribution to diagnosis, and practical management of an MR examination. Eight exercises allow the reader to test the knowledge he has acquired. Signal localization and MR artefacts are reviewed in an appendix

  1. On effect of stability of magnetic resonance position by harmonized field

    International Nuclear Information System (INIS)

    Ivanchenko, E.A.; Tolstoluzhsky, A.P.

    2006-01-01

    The formalism of density matrix in a two level system is used to study the time-periodic modulation of the magnetic field stabilizating the magnetic resonance position. An exact solution for density matrix at resonance is found. It is shown that the fundamental resonance is stable with respect to consistent variations of longitudinal and transversal magnetic fields. A differential equation for the transition probability is obtained. The dependence of time-averaged spin flip probability on the normalized Larmor frequency was numerically researched in different parameter regimes with account of dissipation and decoherence. It is shown that the position of the main resonance is independent of field deformation and dissipation; only the width of resonance line changes upon field deformation and dissipation. The odd parametric (multi-photon) resonance transitions is studied. Static magnetization induced by time-periodic modulated magnetic field is considered. The results of the investigation may be useful for analysis of interference experiments, improvement of magnetic spectrometers and in the field of quantum computing manipulation of q-bits

  2. Magnetic hysteresis effects in superconducting coplanar microwave resonators

    Energy Technology Data Exchange (ETDEWEB)

    Bothner, D.; Gaber, T.; Kemmler, M.; Gruenzweig, M.; Ferdinand, B.; Koelle, D.; Kleiner, R. [Universitaet Tuebingen (Germany); Wuensch, S.; Siegel, M. [Karlsruher Institut fuer Technologie (Germany); Mikheenko, P.; Johansen, T.H. [University of Oslo (Norway)

    2013-07-01

    We present experimental data regarding the impact of external magnetic fields on quality factor and resonance frequency of superconducting microwave resonators in a coplanar waveguide geometry. In particular we focus on the influence of magnetic history and show with the assistance of numerical calculations that the found hysteretic behaviour can be well understood with a highly inhomogeneous microwave current density in combination with established field penetration models for type-II superconducting thin films. Furthermore we have used magneto-optical imaging techniques to check the field distribution which we have assumed in our calculations. Finally, we demonstrate that and how the observed hysteretic behaviour can be used to optimize and tune the resonator performance for possible hybrid quantum sytems in magnetic fields.

  3. Slotted cage resonator for high-field magnetic resonance imaging of rodents

    Energy Technology Data Exchange (ETDEWEB)

    Marrufo, O; Vasquez, F; Solis, S E; Rodriguez, A O, E-mail: arog@xanum.uam.mx [Departamento de Ingenieria Electrica, Universidad Autonoma Metropolitana Iztapalapa, Mexico, DF 09340 (Mexico)

    2011-04-20

    A variation of the high-frequency cavity resonator coil was experimentally developed according to the theoretical frame proposed by Mansfield in 1990. Circular slots were used instead of cavities to form the coil endplates and it was called the slotted cage resonator coil. The theoretical principles were validated via a coil equivalent circuit and also experimentally with a coil prototype. The radio frequency magnetic field, B1, produced by several coil configurations was numerically simulated using the finite-element approach to investigate their performances. A transceiver coil, 8 cm long and 7.6 cm in diameter, and composed of 4 circular slots with a 15 mm diameter on both endplates, was built to operate at 300 MHz and quadrature driven. Experimental results obtained with the slotted cage resonator coil were presented and showed very good agreement with the theoretical expectations for the resonant frequency as a function of the coil dimensions and slots. A standard birdcage coil was also built for performance comparison purposes. Phantom images were then acquired to compute the signal-to-noise ratio of both coils showing an important improvement of the slotted cage coil over the birdcage coil. The whole-body images of the mouse were also obtained showing high-quality images. Volume resonator coils can be reliably built following the physical principles of the cavity resonator design for high-field magnetic resonance imaging applications of rodents.

  4. Evaluation of magnetic resonance velocimetry for steady flow.

    Science.gov (United States)

    Ku, D N; Biancheri, C L; Pettigrew, R I; Peifer, J W; Markou, C P; Engels, H

    1990-11-01

    Whole body magnetic resonance (MR) imaging has recently become an important diagnostic tool for cardiovascular diseases. The technique of magnetic resonance phase velocity encoding allows the quantitative measurement of velocity for an arbitrary component direction. A study was initiated to determine the ability and accuracy of MR velocimetry to measure a wide range of flow conditions including flow separation, three-dimensional secondary flow, high velocity gradients, and turbulence. A steady flow system pumped water doped with manganese chloride through a variety of test sections. Images were produced using gradient echo sequences on test sections including a straight tube, a curved tube, a smoothly converging-diverging nozzle, and an orifice. Magnetic resonance measurements of laminar and turbulent flows were depicted as cross-sectional velocity profiles. MR velocity measurements revealed such flow behavior as spatially varying velocity, recirculation and secondary flows over a wide range of conditions. Comparisons made with published experimental laser Doppler anemometry measurements and theoretical calculations for similar flow conditions revealed excellent accuracy and precision levels. The successful measurement of velocity profiles for a variety of flow conditions and geometries indicate that magnetic resonance imaging is an accurate, non-contacting velocimeter.

  5. Introduction to magnetic resonance and its application to dipole magnet testing

    International Nuclear Information System (INIS)

    Clark, W.G.

    1992-01-01

    An introduction to the features of magnetic resonance that are essential for understanding its application to testing accelerator dipole magnets is presented, including the accuracy that can be expected in field measurements and the factors that limit it. The use of an array of coils to measure the multipole moments of dipole magnets is discussed

  6. Three-dimensional magnetic resonance imaging analysis of hip morphology in the assessment of femoral acetabular impingement

    International Nuclear Information System (INIS)

    Kavanagh, E.C.; Read, P.; Carty, F.; Zoga, A.C.; Parvizi, J.; Morrison, W.B.

    2011-01-01

    Aim: To determine a possible association between femoral-acetabular impingement (FAI) volume and the development of labral tear using a three-dimensional (3D) model reconstruction of the acetabulum and the femoral head. Materials and methods: Magnetic resonance arthrography images of the hip in 42 patients with pain and suspected labral tear were acquired using a 1.5 T MRI machine. Using 3D analysis software, outlines of the acetabular cup and femoral head were drawn and 3D reconstruction obtained. To control for differences in patient size, ratios of acetabulum : femoral head volume (AFV) and acetabulum : femoral head surface area (AFA) were used for analysis. The association between volume of acetabulum : femoral head and FAI was investigated using ANOVA analysis. Results: There were 19 men and 23 women with a mean age of 39 years (range 18-78 years). The average AFV was 0.64 (range 0.37-1.05, SD 0.16) and AFA was 0.73 (range 0.36-1.26, SD 0.23). Herniation pit was significantly associated with a small AFV. Conclusion: Femoral neck herniation pits are associated with a low AFV. Gross volume and surface area ratios do not appear to correlate with labral tears or cartilage loss. This technique will enable more advanced analysis of morphological variations associated with FAI.

  7. Magnetic Resonance Imaging (MRI) -- Head

    Medline Plus

    Full Text Available Toggle navigation Test/Treatment Patient Type Screening/Wellness Disease/Condition Safety En Español More Info Images/Videos About Us News Physician Resources Professions Site Index A-Z Magnetic Resonance Imaging (MRI) - ...

  8. Children's (Pediatric) Magnetic Resonance Imaging

    Medline Plus

    Full Text Available ... MRI) exam. 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 Catheter Angiography Magnetic Resonance, ...

  9. Imaging by magnetic resonance

    International Nuclear Information System (INIS)

    Duroure, J.F.; Serpolay, H.; Vallens, D.

    1995-01-01

    Here are described the advanced technology for nuclear magnetic resonance imaging: reduction of acquisition times, and rebuilding times, images quality improvement. The tendency is to open the machines at low and middle field, on a market being at 10% of NMR I sales, with economical, scientifical and ergonomic reasons broadly developed by constructors

  10. Suppressing magnetic island growth by resonant magnetic perturbation

    Science.gov (United States)

    Yu, Q.; Günter, S.; Lackner, K.

    2018-05-01

    The effect of externally applied resonant magnetic perturbations (RMPs) on the growth of magnetic islands is investigated based on two-fluid equations. It is found that if the local bi-normal electron fluid velocity at the resonant surface is sufficiently large, static RMPs of the same helicity and of moderate amplitude can suppress the growth of magnetic islands in high-temperature plasmas. These islands will otherwise grow, driven by an unfavorable plasma current density profile and bootstrap current perturbation. These results indicate that the error field can stabilize island growth, if the error field amplitude is not too large and the local bi-normal electron fluid velocity is not too low. They also indicate that applied rotating RMPs with an appropriate frequency can be utilized to suppress island growth in high-temperature plasmas, even for a low bi-normal electron fluid velocity. A significant change in the local equilibrium plasma current density gradient by small amplitude RMPs is found for realistic plasma parameters, which are important for the island stability and are expected to be more important for fusion reactors with low plasma resistivity.

  11. Magnetic moment oscillation in ammonium perchlorate in a DC SQUID-based magnetic resonance experiment

    International Nuclear Information System (INIS)

    Montero, V.; Cernicchiaro, G.

    2008-01-01

    In this work we describe experimental results in which a DC SQUID (superconducting quantum interference device) is used as free induction decay detector. Measurements of a solid ammonium perchlorate (NH 4 ClO 4 ) sample were performed, in zero field, at 4.2 K. Unexpected magnetic moment oscillations were detected at 1.5 kHz. The computation of the magnetic fields suggests that the proton nuclear magnetic resonance may explain the measured resonance, considering reorientation of the ammonium group by quantum tunneling of protons and a magnetic proton dipole-dipole intermolecular interaction model

  12. Magnetic Resonance Imaging (MRI) -- Head

    Medline Plus

    Full Text Available ... are the limitations of MRI of the Head? What is MRI of the Head? Magnetic resonance imaging ( ... brain) in routine clinical practice. top of page What are some common uses of the procedure? MR ...

  13. Magnetic Resonance Imaging (MRI) -- Head

    Medline Plus

    Full Text Available ... is not harmful, but it may cause some medical devices to malfunction. Most orthopedic implants pose no ... Head? Magnetic resonance imaging (MRI) is a noninvasive medical test that physicians use to diagnose medical conditions. ...

  14. Children's (Pediatric) Magnetic Resonance Imaging

    Medline Plus

    Full Text Available Toggle navigation Test/Treatment Patient Type Screening/Wellness Disease/Condition Safety En Español More Info Images/Videos About Us News Physician Resources Professions Site Index A-Z Children’s (Pediatric) Magnetic Resonance ...

  15. Magnetic Resonance Imaging (MRI) -- Head

    Medline Plus

    Full Text Available ... be necessary. Your doctor will explain the exact reason why another exam is requested. Sometimes a follow- ... necessary in trauma situations. Although there is no reason to believe that magnetic resonance imaging harms the ...

  16. Children's (Pediatric) Magnetic Resonance Imaging

    Medline Plus

    Full Text Available ... it is useful to bring that to the attention of the technologist or scheduler before the exam. ... patient for magnetic resonance imaging (MRI) exam. View full size with caption Pediatric Content Some imaging tests ...

  17. Magnetic Resonance Imaging (MRI) -- Head

    Medline Plus

    Full Text Available ... it is useful to bring that to the attention of the scheduler before the exam and bring ... Image Gallery Magnetic Resonance Imaging (MRI) procedure View full size with caption Pediatric Content Some imaging tests ...

  18. Simulation of a resonant-type ring magnet power supply with multiple resonant cells and energy storage chokes

    International Nuclear Information System (INIS)

    Kim, J.M.S.; Blackmore, E.W.; Reiniger, K.W.

    1992-01-01

    For the TRIUMF KAON Factory Booster Ring, a resonant-type magnet power supply has been proposed for the dipole magnet excitation. The Booster Ring magnet power supply system based on resonant circuits, coupled with distributed energy make-up networks, is a complex system, sensitive to many system parameters. When multiple resonant cells, each with its own energy make-up network, are connected in a ring, it is very difficult to derive closed-form solutions to determine the operating conditions of the power supply system. A meaningful way to understand and analyze such a complex system is to use a simulation tool. This paper presents the analysis of operating conditions of the resonant-type ring magnet power supply with multiple resonant cells, using the circuit simulation tool, SPICE. The focus of the study is on the effect of circuit parameter variations in energy storage chokes

  19. [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.

  20. Soft X-ray resonant scattering from magnetic heterostructures

    International Nuclear Information System (INIS)

    Grabis, J.

    2005-01-01

    Heterogenous magnetic multilayers are of great interest both because of their relevance for technological applications and since they provide model systems to understand magnetic behavior and interactions. Soft x-ray resonant magnetic scattering (XRMS) allows to determine element-specific and depth-resolving information of the local magnetic order of such systems. Within the framework of the present thesis the diffractometer ALICE for soft XRMS has been constructed. XRMS measurements of two different physical systems are presented in this thesis: The antiferromagnetic and ferromagnetic order in interlayer exchange-coupled Fe/Cr(001) superlattices are studied as a function of the applied field by measuring the reflected intensity at different positions in reciprocal space. Thin films and multilayers of the Heusler compound Co 2 MnGe are studied by means of soft x-ray absorption spectroscopy, magnetic circular dichroism and resonant magnetic scattering

  1. Nuclear magnetic resonance

    International Nuclear Information System (INIS)

    Cremin, B.J.

    1981-01-01

    Recent advances in diagnostic imaging, have been the medical application of nuclear magnetic resonance (NMR). It's been used to study the structure of various compounds in chemistry and physics, and in the mid-1970 to produce images of rabbits and eventually of the human hand and head. The images are produced by making use of the nuclear magnetization of the hydrogen ion, or proton, that is present in biological material to record the density distribution of protons in cellular water and lipids. An exploration of the end-results of complicated free induction decay signals, that have been digitized and frequency-analysed by mathematical computerized techniques to produce an image of tissue density, is given. At present NMR produces images comparable to those of early computed tomography

  2. Artifacts Affecting Musculoskeletal Magnetic Resonance Imaging: Their Origins and Solutions.

    Science.gov (United States)

    Roth, Eira; Hoff, Michael; Richardson, Michael L; Ha, Alice S; Porrino, Jack

    2016-01-01

    Among articles within the radiology literature, few present the manifestations of magnetic resonance imaging artifacts in a clinically oriented manner. Recognizing such artifacts is imperative given the increasing clinical use of magnetic resonance imaging and the emphasis by the American Board of Radiology on practical physics applications. The purpose of this article is to present magnetic resonance physics principles visually and conceptually in the context of common musculoskeletal radiology artifacts and their solutions, described using nonmathematical explanations. Copyright © 2016 Elsevier Inc. All rights reserved.

  3. Children's (Pediatric) Magnetic Resonance Imaging

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    Full Text Available ... or thyroid problems. Any of these conditions may influence the decision on whether contrast material will be ... bear denotes child-specific content. Related Articles and Media Catheter Angiography Magnetic Resonance, Functional (fMRI) - Brain Children's ( ...

  4. Magnetic Resonance Imaging (MRI) -- Head

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    Full Text Available ... bear denotes child-specific content. Related Articles and Media MR Angiography (MRA) Magnetic Resonance, Functional (fMRI) - Brain ... the web pages found at these links. About Us | Contact Us | FAQ | Privacy | Terms of Use | Links | ...

  5. Children's (Pediatric) Magnetic Resonance Imaging

    Medline Plus

    Full Text Available ... bear denotes child-specific content. Related Articles and Media Catheter Angiography Magnetic Resonance, Functional (fMRI) - Brain Children's ( ... the web pages found at these links. About Us | Contact Us | FAQ | Privacy | Terms of Use | Links | ...

  6. Children's (Pediatric) Magnetic Resonance Imaging

    Medline Plus

    Full Text Available ... As the hydrogen atoms return to their usual alignment, they emit different amounts of energy that vary ... story about radiology? Share your patient story here Images × Image Gallery Radiologist prepping patient for magnetic resonance ...

  7. Magnetic Resonance Imaging (MRI) -- Head

    Medline Plus

    Full Text Available ... As the hydrogen atoms return to their usual alignment, they emit different amounts of energy that vary ... story about radiology? Share your patient story here Images × Image Gallery Magnetic Resonance Imaging (MRI) procedure View ...

  8. Lymphoma of uterine cervix: magnetic resonance imaging findings

    Energy Technology Data Exchange (ETDEWEB)

    Kanaan, Daniel; Constantino, Carolina Pesce Lamas; Souza, Rodrigo Canellas de, E-mail: daniel.kanaan@hotmail.com [Department of Radiology, Universidade Federal do Rio de Janeiro (UFRJ), RJ (Brazil); Parente, Daniella Braz [Instituto D' Or de Pesquisa e Ensino, Rio de Janeiro, RJ (Brazil)

    2012-05-15

    Lymphoma of the cervix is a rare disease. About 1.0% to 1.5% of extranodal lymphomas originates in the female genital tract. The clinical presentation of this condition is nonspecific and magnetic resonance imaging is important for diagnostic elucidation. The present report describes the case of a 80-year-old patient with lumbar pain, whose magnetic resonance imaging showed a large uterine mass. The final diagnosis was lymphoma. (author)

  9. Demonstration of Magnetic Dipole Resonances of Dielectric Nanospheres in the Visible Region

    DEFF Research Database (Denmark)

    Evlyukhin, A. B.; Novikov, S. M.; Zywietz, U.

    2012-01-01

    Strong resonant light scattering by individual spherical Si nanoparticles is experimentally demonstrated, revealing pronounced resonances associated with the excitation of magnetic and electric modes in these nanoparticles. It is shown that the low-frequency resonance corresponds to the magnetic...... dipole excitation. Due to high permittivity, the magnetic dipole resonance is observed in the visible spectral range for Si nanoparticles with diameters of similar to 200 nm, thereby opening a way to the realization of isotropic optical metamaterials with strong magnetic responses in the visible region....

  10. Magnetic resonance investigation of magnetic-labeled baker's yeast cells

    International Nuclear Information System (INIS)

    Godoy Morais, J.P.M.; Azevedo, R.B.; Silva, L.P.; Lacava, Z.G.M.; Bao, S.N.; Silva, O.; Pelegrini, F.; Gansau, C.; Buske, N.; Safarik, I.; Safarikova, M.; Morais, P.C.

    2004-01-01

    In this study, the interaction of DMSA-coated magnetite nanoparticles (5 and 10 nm core-size) with Saccharomyces cerevisae was investigated using magnetic resonance (MR) and transmission electron microscopy (TEM). The TEM micrographs revealed magnetite nanoparticles attached externally to the cell wall. The MR data support the strong interaction among the nanoparticles supported by the cells. A remarkable shift in the resonance field was used as signature of particle attachment to the cell wall

  11. Application of the annihilation and creation operators in magnetic resonance problems

    International Nuclear Information System (INIS)

    Nosel, W.

    1981-01-01

    Application of the annihilation and creation operators in the following problems is presented: in the resonance of the free spins in rotating and oscillating magnetic field, in the influence of the nonresonance magnetic fields on magnetic resonance, in the thermodynamics of the spins with dipolar interaction and in the nuclear magnetic relaxation. (author)

  12. Method for increasing nuclear magnetic resonance signals in living biological tissue

    International Nuclear Information System (INIS)

    Krongrad, A.

    1995-01-01

    A method of enhancing a magnetic resonance comprising the steps of administering a quantity of a selected magnetic isotope to a living biological tissue at a concentration greater than the naturally occurring concentration of such isotope and detecting magnetic resonance signal from the administered magnetic isotope in the living biological tissue. (author)

  13. The market for magnetic resonance spectroscopy

    International Nuclear Information System (INIS)

    Carlson, L.

    1990-01-01

    The medical market is, at present, the most dominant market for low T c superconductors. Indeed, without magnetic resonance imaging (MRI), there would hardly be a low T c superconductor market at all. According to the author, any development that can expand the medical market for MRI machines would be a welcome one. This paper reports how the recent advances in magnetic resonance spectroscopy (MRS) are such a development. While the principle of MRS has bee around as long as MRI, only recently have advances in technique, computer programming and magnet technology allowed MRS to advance to a point where it may become an important technology-one that could increase the medical market for superconductors. The author discussed how MRS can be used to analyze oil core samples for their oil content, oil/water ratios, how the oil is bound and how to extract it

  14. Magnetic Barkhausen noise measurement by resonant coil method

    Energy Technology Data Exchange (ETDEWEB)

    Capo-Sanchez, J. [Departamento de Fisica, Facultad de Ciencias Naturales, Universidad de Oriente, Av. Patricio Lumumba s/n, 90500 Santiago de Cuba (Cuba)], E-mail: jcapo@usp.br; Padovese, L. [Departamento de Engenharia Mecanica, Escola Politecnica, Universidade de Sao Paulo, Av. Prof. Mello Moraes, 2231, 05508-900 Sao Paulo (Brazil)

    2009-09-15

    This paper describes a powerful new technique for nondestructive evaluation of ferromagnetic material. A method has been developed for measuring magnetic Barkhausen signals under different coil resonance frequencies. The measurements allow one to establish the behavior relating the power spectral density maximum and the resonant coil frequency. Time-frequency analysis of Barkhausen signals puts in evidence the tuning regions for each coil, and allows clear identification of each contribution to the Barkhausen signal spectrum. This concept was used in order to evaluate the relation between the degree of plastic deformation in carbon steel samples, and the power spectral density maximum at different resonance frequencies. This result also makes it possible to the selectively modify measurement sensibility to the magnetic Barkhausen signal by using different resonance frequencies.

  15. Magnetic Resonance Imaging (MRI) -- Head

    Medline Plus

    Full Text Available ... structures of the brain and can also provide functional information (fMRI) in selected cases. MR images of ... Articles and Media MR Angiography (MRA) Magnetic Resonance, Functional (fMRI) - Brain Head and Neck Cancer Treatment Brain ...

  16. Imaging of juvenile spondyloarthritis. Part II: Ultrasonography and magnetic resonance imaging

    Directory of Open Access Journals (Sweden)

    Iwona Sudoł-Szopińska

    2017-09-01

    Full Text Available Juvenile spondyloarthropathies are mainly manifested by symptoms of peripheral arthritis and enthesitis. Early involvement of sacroiliac joints and spine is exceptionally rare in children; this usually happens in adulthood. Conventional radiographs visualize late inflammatory lesions. Early diagnosis is possible with the use of ultrasonography and magnetic resonance imaging. The first part of the article presented classifications and radiographic presentation of juvenile spondyloarthropathies. This part discusses changes seen on ultrasonography and magnetic resonance imaging. In patients with juvenile spondyloarthropathies, these examinations are conducted to diagnose inflammatory lesions in peripheral joints, tendon sheaths, tendons and bursae. Moreover, magnetic resonance also shows subchondral bone marrow edema, which is considered an early sign of inflammation. Ultrasonography and magnetic resonance imaging do not show specific lesions for any rheumatic disease. Nevertheless, they are conducted for early diagnosis, treatment monitoring and identifying complications. This article presents a spectrum of inflammatory changes and discusses the diagnostic value of ultrasonography and magnetic resonance imaging.

  17. 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.)

  18. Children's (Pediatric) Magnetic Resonance Imaging

    Medline Plus

    Full Text Available ... Magnetic Resonance Imaging 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 ...

  19. Magnetic resonance imaging of generalised musculo-skeletal diseases

    International Nuclear Information System (INIS)

    Kaiser, W.A.; Schalke, B.C.G.

    1989-01-01

    The results presented are drawn from 320 examinations by NMR imaging of patients with various systemic muscle diseases (dystrophies, myositides, metabolic disorders), and are interpreted so as to explain the relevant characteristic distribution patterns of the degenerative processes in the femoral musculature as shown by the NMR images. Four basic patterns are presented according to the criteria homogeneous-heterogeneous and symmetric-asymmetric, and the diseases identified by the differential diagnostic evaluation are discussed. The optimum measuring conditions for magnetic resonance imaging of the musculature are given, and the specific magnetic resonance criteria of myositides, neurogenic myopathies, myofonous dystrophies, c.n. polio, morbus Pompe, familial hypokalemic paralysis, centronuclear mypathy, morbus Duchenne are explained. The significance of NMR imaging with regard to biopsy or therapy planning is discussed, and magnetic resonance examination is recommended to be applied prior to biopsy. (orig.) [de

  20. Ultra-small v-shaped gold split ring resonators for biosensing using fundamental magnetic resonance in the visible spectrum

    Science.gov (United States)

    Mauluidy Soehartono, Alana; Mueller, Aaron David; Tobing, Landobasa Yosef Mario; Chan, Kok Ken; Zhang, Dao Hua; Yong, Ken-Tye

    2017-10-01

    Strong light localization within metal nanostructures occurs by collective oscillations of plasmons in the form of electric and magnetic resonances. This so-called localized surface plasmon resonance (LSPR) has gained much interest in the development of low-cost sensing platforms in the visible spectrum. However, demonstrations of LSPR-based sensing are mostly limited to electric resonances due to the technological limitations for achieving magnetic resonances in the visible spectrum. In this work, we report the first demonstration of LSPR sensing based on fundamental magnetic resonance in the visible spectrum using ultrasmall gold v-shaped split ring resonators. Specifically, we show the ability for detecting adsorption of bovine serum albumin and cytochrome c biomolecules at monolayer levels, and the selective binding of protein A/G to immunoglobulin G.

  1. Physics of Magnetic Resonance. Chapter 14

    Energy Technology Data Exchange (ETDEWEB)

    Song, Hee Kwon [Hospital of the University of Pennsylvania, Philadelphia (United States)

    2014-09-15

    The discovery of nuclear magnetic resonance (NMR), a property of nuclei in a magnetic field where they are able to absorb applied radiofrequency (RF) energy and subsequently release it at a specific frequency, goes back many decades to the early 1900s. Physicist Isidor I. Rabi, fascinated by the work of Otto Stern and Walther Gerlach which demonstrated that particles have intrinsic quantum properties, delved into the magnetic properties of nuclei, and in 1938 Rabi discovered the phenomenon of NMR. Several years later, in 1946, Felix Bloch and Edward Purcell refined the methods and successfully measured the NMR signal from liquids and solids. For their discoveries, Rabi received the Nobel Prize for physics in 1944 and Bloch and Purcell in 1952. While Rabi, Bloch, Purcell and other physicists working in this field had laid the foundations, a major discovery that transformed the NMR phenomenon for imaging was not made until 1973, when Paul Lauterbur developed a method for spatially encoding the NMR signal by utilizing linear magnetic field gradients. About the same time, Peter Mansfield had also discovered a means of determining the spatial structure of solids by introducing a linear gradient across the object. The idea of applying magnetic field gradients to induce spatially varying resonance frequencies to resolve the spatial distribution of magnetization was a major milestone and the beginning of magnetic resonance imaging (MRI). For their work, Lauterbur and Mansfield were awarded the Nobel Prize for medicine in 2003. Since its discovery, MRI has quickly become one of the most important medical imaging devices available to physicians today. Unlike other imaging modalities, such as X ray and computed tomography, MRI does not involve ionizing radiation. MRI also offers superior soft tissue contrast that is not possible with other imaging modalities. Furthermore, in MRI, the desired level of image contrast among different tissues can often be precisely controlled

  2. 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

  3. Mesoscopic Magnetic Resonance Spectroscopy with a Remote Spin Sensor

    Science.gov (United States)

    Xie, Tianyu; Shi, Fazhan; Chen, Sanyou; Guo, Maosen; Chen, Yisheng; Zhang, Yixing; Yang, Yu; Gao, Xingyu; Kong, Xi; Wang, Pengfei; Tateishi, Kenichiro; Uesaka, Tomohiro; Wang, Ya; Zhang, Bo; Du, Jiangfeng

    2018-06-01

    Quantum sensing based on nitrogen-vacancy (N -V ) centers in diamond has been developed as a powerful tool for microscopic magnetic resonance. However, the reported sensor-to-sample distance is limited within tens of nanometers resulting from the cubic decrease of the signal of spin fluctuation with the increasing distance. Here we extend the sensing distance to tens of micrometers by detecting spin polarization rather than spin fluctuation. We detect the mesoscopic magnetic resonance spectra of polarized electrons of a pentacene-doped crystal, measure its two typical decay times, and observe the optically enhanced spin polarization. This work paves the way for the N -V -based mesoscopic magnetic resonance spectroscopy and imaging at ambient conditions.

  4. Upper Hybrid Resonance of Microwaves with a Large Magnetized Plasma Sheet

    International Nuclear Information System (INIS)

    Huo Wenqing; Guo Shijie; Ding Liang; Xu Yuemin

    2013-01-01

    A large magnetized plasma sheet with size of 60 cm × 60 cm × 2 cm was generated by a linear hollow cathode discharge under the confinement of a uniform magnetic field generated by a Helmholtz Coil. The microwave transmission characteristic of the plasma sheet was measured for different incident frequencies, in cases with the electric field polarization of the incident microwave either perpendicular or parallel to the magnetic field. In this measurement, parameters of the plasma sheet were changed by varying the discharge current and magnetic field intensity. In the experiment, upper hybrid resonance phenomena were observed when the electric field polarization of the incident wave was perpendicular to the magnetic field. These resonance phenomena cannot be found in the case of parallel polarization incidence. This result is consistent with theoretical consideration. According to the resonance condition, the electron density values at the resonance points are calculated under various experimental conditions. This kind of resonance phenomena can be used to develop a specific method to diagnose the electron density of this magnetized plasma sheet apparatus. Moreover, it is pointed out that the operating parameters of the large plasma sheet in practical applications should be selected to keep away from the upper hybrid resonance point to prevent signals from polarization distortion

  5. Resonant inverter supplied Interior Permanent Magnet (IPM) motor ...

    African Journals Online (AJOL)

    In this paper, rotor position in relation to the resonant frequency component current in the stator winding of DC-voltage link resonant inverter supplied Interior Permanent Magnet (IPM) motor has been developed. Six reference frames are used to relate the rotor position angle to the resonant frequency component current ...

  6. Magnetic structure and resonance properties of hexagonal antidot lattice

    International Nuclear Information System (INIS)

    Marchenko, A.I.; Krivoruchko, V.N.

    2012-01-01

    Static and resonance properties of ferromagnetic films with an antidot lattice (pores in the film) are studied. The description of the system is based on micromagnetic modeling and analytical solution of the Landau-Lifshitz equation. The dependences of ferromagnetic resonance spectra on the in-plane direction of applied magnetic field and on the lattice parameters are investigated. The dependences of a dynamic system response on frequency at fixed magnetic field and on field at fixed frequency, when the field changes cause the static magnetic order to change are explored. It is found that the specific peculiarities of the system dynamics leave unchange for both of these experimental conditions. Namely, for low damping the resonance spectra contain three quasi-homogeneous modes which are due to the resonance of different regions (domains) of the antidot lattice cell. It is shown the angular field dependences of each mode are characterized by a twofold symmetry and the related easy axes are mutually rotated by 60 degrees. As the result, a hexagonal symmetry of the system static and dynamic magnetic characteristics is realized. The existence in the resonance spectrum of several quasi-homogeneous modes related to different regions of the unit cell could be fundamental for working elements of magnonic devices.

  7. Ferromagnetic linewidth measurements employing electrodynamic model of the magnetic plasmon resonance

    Science.gov (United States)

    Krupka, Jerzy; Aleshkevych, Pavlo; Salski, Bartlomiej; Kopyt, Pawel

    2018-02-01

    The mode of uniform precession, or Kittel mode, in a magnetized ferromagnetic sphere, has recently been proven to be the magnetic plasmon resonance. In this paper we show how to apply the electrodynamic model of the magnetic plasmon resonance for accurate measurements of the ferromagnetic resonance linewidth ΔH. Two measurement methods are presented. The first one employs Q-factor measurements of the magnetic plasmon resonance coupled to the resonance of an empty metallic cavity. Such coupled modes are known as magnon-polariton modes, i.e. hybridized modes between the collective spin excitation and the cavity excitation. The second one employs direct Q-factor measurements of the magnetic plasmon resonance in a filter setup with two orthogonal semi-loops used for coupling. Q-factor measurements are performed employing a vector network analyser. The methods presented in this paper allow one to extend the measurement range of the ferromagnetic resonance linewidth ΔH well beyond the limits of the commonly used measurement standards in terms of the size of the samples and the lowest measurable linewidths. Samples that can be measured with the newly proposed methods may have larger size as compared to the size of samples that were used in the standard methods restricted by the limits of perturbation theory.

  8. Imaging of the hip joint. Computed tomography versus magnetic resonance imaging

    Science.gov (United States)

    Lang, P.; Genant, H. K.; Jergesen, H. E.; Murray, W. R.

    1992-01-01

    The authors reviewed the applications and limitations of computed tomography (CT) and magnetic resonance (MR) imaging in the assessment of the most common hip disorders. Magnetic resonance imaging is the most sensitive technique in detecting osteonecrosis of the femoral head. Magnetic resonance reflects the histologic changes associated with osteonecrosis very well, which may ultimately help to improve staging. Computed tomography can more accurately identify subchondral fractures than MR imaging and thus remains important for staging. In congenital dysplasia of the hip, the position of the nonossified femoral head in children less than six months of age can only be inferred by indirect signs on CT. Magnetic resonance imaging demonstrates the cartilaginous femoral head directly without ionizing radiation. Computed tomography remains the imaging modality of choice for evaluating fractures of the hip joint. In some patients, MR imaging demonstrates the fracture even when it is not apparent on radiography. In neoplasm, CT provides better assessment of calcification, ossification, and periosteal reaction than MR imaging. Magnetic resonance imaging, however, represents the most accurate imaging modality for evaluating intramedullary and soft-tissue extent of the tumor and identifying involvement of neurovascular bundles. Magnetic resonance imaging can also be used to monitor response to chemotherapy. In osteoarthrosis and rheumatoid arthritis of the hip, both CT and MR provide more detailed assessment of the severity of disease than conventional radiography because of their tomographic nature. Magnetic resonance imaging is unique in evaluating cartilage degeneration and loss, and in demonstrating soft-tissue alterations such as inflammatory synovial proliferation.

  9. Resonances and dipole moments in dielectric, magnetic, and magnetodielectric cylinders

    DEFF Research Database (Denmark)

    Dirksen, A.; Arslanagic, Samel; Breinbjerg, Olav

    2011-01-01

    An eigenfunction solution to the problem of plane wave scattering by dielectric, magnetic, and magnetodielectric cylinders is used for a systematic investigation of their resonances. An overview of the resonances with electric and magnetic dipole moments, needed in, e.g., the synthesis...

  10. Evanescent Waves Nuclear Magnetic Resonance

    DEFF Research Database (Denmark)

    Halidi, El Mohamed; Nativel, Eric; Akel, Mohamad

    2016-01-01

    Nuclear Magnetic Resonance spectroscopy and imaging can be classified as inductive techniques working in the near- to far-field regimes. We investigate an alternative capacitive detection with the use of micrometer sized probes positioned at sub wavelength distances of the sample in order...

  11. Children's (Pediatric) Magnetic Resonance Imaging

    Medline Plus

    Full Text Available ... of which shows a thin slice of the body. The images can then be studied from different angles by ... about radiology? Share your patient story here Images ... Articles and Media Catheter Angiography Magnetic Resonance, Functional (fMRI) - Brain Children's ( ...

  12. Magnetic Resonance Imaging (MRI) -- Head

    Medline Plus

    Full Text Available Toggle navigation Test/Treatment Patient Type Screening/Wellness Disease/Condition Safety En Español More Info Images/Videos About Us News Physician ... Magnetic resonance imaging (MRI) is a noninvasive medical test that physicians use to diagnose medical conditions. MRI ...

  13. Children's (Pediatric) Magnetic Resonance Imaging

    Medline Plus

    Full Text Available Toggle navigation Test/Treatment Patient Type Screening/Wellness Disease/Condition Safety En Español More Info Images/Videos About Us News Physician ... Magnetic resonance imaging (MRI) is a noninvasive medical test that physicians use to diagnose medical conditions. MRI ...

  14. Basis of the nuclear magnetic resonance

    International Nuclear Information System (INIS)

    Bahceli, S.

    1996-08-01

    The aim of this book which is translated from English language is to explain the physical and mathematical basis of nuclear magnetic resonance (NMR). There are nine chapters covering different aspects of NMR. In the firs chapter fundamental concepts of quantum mechanics are given at a level suitable for readers to understand NMR fully. The remaining chapters discuss the magnetic properties of nucleus, the interactions between atoms and molecules, continuous wave NMR, pulsed NMR, nuclear magnetic relaxation and NMR of liquids

  15. 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

  16. Harmonic detection of magnetic resonance for sensitivity improvement of optical atomic magnetometers

    Energy Technology Data Exchange (ETDEWEB)

    Ranjbaran, M. [Laser and Plasma Research Institute, Shahid Beheshti University, Tehran (Iran, Islamic Republic of); Tehranchi, M.M., E-mail: teranchi@sbu.ac.ir [Laser and Plasma Research Institute, Shahid Beheshti University, Tehran (Iran, Islamic Republic of); Physics Department, Shahid Beheshti University, Tehran (Iran, Islamic Republic of); Hamidi, S.M. [Laser and Plasma Research Institute, Shahid Beheshti University, Tehran (Iran, Islamic Republic of); Khalkhali, S.M.H. [Physics Department, Kharazmi University, Tehran (Iran, Islamic Republic of)

    2017-02-15

    Highly sensitive atomic magnetometers use optically detected magnetic resonance of atomic spins to measure extremely weak magnetic field changes. The magnetometer sensitivity is directly proportional to the ratio of intensity to line-shape of the resonance signal. To obtain narrower resonance signal, we implemented harmonic detection of magnetic resonance method in M{sub x} configuration. The nonlinear spin polarization dynamics in detection of the higher harmonics were employed in phenomenological Bloch equations. The measured and simulated harmonic components of the resonance signals in frequency domain yielded significantly narrower line-width accompanying much improved sensitivity. Our results confirm the sensitivity improvement by a factor of two in optical atomic magnetometer via second harmonic signal which can open a new insight in the weak magnetic field measurement system design. - Highlights: • Highly sensitive atomic magnetometers have been used to measure weak magentic filed. • To obtain narrower resonance signal, we impalnted harmonic detection of magnetic resonance. • The nonlinear spin polarization dynamics in detetion of the higher harmonics were imployed.

  17. Magnetic resonance spectroscopy and imaging in cerebral ischemia

    International Nuclear Information System (INIS)

    Rijen, P.C. van.

    1991-01-01

    In-vivo proton and phosphorus magnetic resonance spectroscopy was used to detect changes in cerebral metabolism during ischemia and other types of metabolic stress. Magnetic resonance imaging was performed in an animal model to observe morphological alterations during focal cerebral ischemia. Spectroscopy was performed in animal models with global ischemia, in volunteers during hyperventilation and pharmaco-logically altered cerebral perfusion, and in patients with acute and prolonged focal cerebral ischemia. (author). 396 refs.; 44 figs.; 14 tabs

  18. Low losses left-handed materials with optimized electric and magnetic resonance

    Science.gov (United States)

    Zhou, Xin; Liu, Yahong; Zhao, Xiaopeng

    2010-03-01

    We propose that the losses in left-handed materials (LHMs) can be significantly affected by changing the coupling relationship between electric and magnetic resonance. A double bowknot shaped structure (DBS) is used to construct the LHMs. And the magnetic resonance of the DBS, which resonated in the case of lower and higher frequencies than the electric resonant dip, is studied in simulation and experiment by tailoring the structural parameters. The case of magnetic resonance located at low electric resonance frequencies band is confirmed to have relatively low losses. Using full wave simulation of prism shaped structure composed of DBS unit cells, we prove the negative refraction behavior in such a frame. This study can serve as a guide for designing other similar metal-dielectric-metal (MDM) in low losses at terahertz or higher frequencies.

  19. Proceedings of the 4. Brazilian meeting on magnetic resonance. Abstracts

    International Nuclear Information System (INIS)

    1996-01-01

    This publication contains the abstracts of the papers presented during the 4. Brazilian meeting on magnetic resonance and also during the Course on advances in nuclear magnetic resonance. Works on the areas of materials, rare earths, polymers, structural chemical analysis and NMR spectra are presented

  20. Nuclear magnetic resonance spectroscopy

    International Nuclear Information System (INIS)

    Rueterjans, H.

    1987-01-01

    Contributions by various authors who are working in the field of NMR imaging present the current status and the perspectives of in-vivo nuclear magnetic resonance spectroscopy, explaining not only the scientific and medical aspects, but also technical and physical principles as well as questions concerning practical organisation and training, and points of main interest for further research activities. (orig./TRV) [de

  1. Nuclear magnetic resonance imaging

    International Nuclear Information System (INIS)

    1983-06-01

    This report summarises the aspects of nuclear magnetic resonance imaging (NMRI) considered by the National Health Technology Advisory Panel and makes recommendations on its introduction in Australia with particular regard to the need for thorough evaluation of its cost effectiveness. Topics covered are: principles of the technique, equipment required, installation, costs, reliability, performance parameters, clinical indications, training and staff requirements, and safety considerations

  2. Adjunctive role of preoperative liver magnetic resonance imaging for potentially resectable pancreatic cancer.

    Science.gov (United States)

    Kim, Hyoung Woo; Lee, Jong-Chan; Paik, Kyu-Hyun; Kang, Jingu; Kim, Young Hoon; Yoon, Yoo-Seok; Han, Ho-Seong; Kim, Jaihwan; Hwang, Jin-Hyeok

    2017-06-01

    The adjunctive role of magnetic resonance imaging of the liver before pancreatic ductal adenocarcinoma has been unclear. We evaluated whether the combination of hepatic magnetic resonance imaging with multidetector computed tomography using a pancreatic protocol (pCT) could help surgeons select appropriate candidates and decrease the risk of early recurrence. We retrospectively enrolled 167 patients in whom complete resection was achieved without grossly visible residual tumor; 102 patients underwent pCT alone (CT group) and 65 underwent both hepatic magnetic resonance imaging and pCT (magnetic resonance imaging group). By adding hepatic magnetic resonance imaging during preoperative evaluation, hepatic metastases were newly discovered in 3 of 58 patients (5%) without hepatic lesions on pCT and 17 of 53 patients (32%) with indeterminate hepatic lesions on pCT. Patients with borderline resectability, a tumor size >3 cm, or preoperative carbohydrate antigen 19-9 level >1,000 U/mL had a greater rate of hepatic metastasis on subsequent hepatic magnetic resonance imaging. Among 167 patients in whom R0/R1 resection was achieved, the median overall survival was 18.2 vs 24.7 months (P = .020) and the disease-free survival was 8.5 vs 10.0 months (P = .016) in the CT and magnetic resonance imaging groups, respectively (median follow-up, 18.3 months). Recurrence developed in 82 (80%) and 43 (66%) patients in the CT and magnetic resonance imaging groups, respectively. The cumulative hepatic recurrence rate was greater in the CT group than in the magnetic resonance imaging group (P magnetic resonance imaging should be considered in patients with potentially resectable pancreatic ductal adenocarcinoma, especially those with high tumor burden. Copyright © 2017 Elsevier Inc. All rights reserved.

  3. Multiple systems atrophy: Differentiation and findings by Magnetic resonance

    International Nuclear Information System (INIS)

    Vargas Velez, Sergio Alberto; Alzate Betancur, Catalina Maria

    2006-01-01

    Multiple system atrophy (MSA) is a neuro degenerative disorder of undetermined cause, characterized clinically by Parkinson's, autonomic, cerebellar or pyramidal sing and symptoms. lts differentiation from Parkinson's disease may be difficult, mainly in the early stages owing to overlapping features. Magnetic resonance imaging has demonstrated usefulness in MSA diagnosis and in differentiation with Parkinson's disease. One case with magnetic resonance findings is described

  4. Rotatable Small Permanent Magnet Array for Ultra-Low Field Nuclear Magnetic Resonance Instrumentation: A Concept Study.

    Science.gov (United States)

    Vogel, Michael W; Giorni, Andrea; Vegh, Viktor; Pellicer-Guridi, Ruben; Reutens, David C

    2016-01-01

    We studied the feasibility of generating the variable magnetic fields required for ultra-low field nuclear magnetic resonance relaxometry with dynamically adjustable permanent magnets. Our motivation was to substitute traditional electromagnets by distributed permanent magnets, increasing system portability. The finite element method (COMSOL®) was employed for the numerical study of a small permanent magnet array to calculate achievable magnetic field strength, homogeneity, switching time and magnetic forces. A manually operated prototype was simulated and constructed to validate the numerical approach and to verify the generated magnetic field. A concentric small permanent magnet array can be used to generate strong sample pre-polarisation and variable measurement fields for ultra-low field relaxometry via simple prescribed magnet rotations. Using the array, it is possible to achieve a pre-polarisation field strength above 100 mT and variable measurement fields ranging from 20-50 μT with 200 ppm absolute field homogeneity within a field-of-view of 5 x 5 x 5 cubic centimetres. A dynamic small permanent magnet array can generate multiple highly homogeneous magnetic fields required in ultra-low field nuclear magnetic resonance (NMR) and magnetic resonance imaging (MRI) instruments. This design can significantly reduce the volume and energy requirements of traditional systems based on electromagnets, improving portability considerably.

  5. Image production by magnetic resonance: transparency via the atom

    International Nuclear Information System (INIS)

    Kanel, A.

    1984-01-01

    The author gives a general description of the nuclear magnetic resonance technique to study the human body. The use of superconducting magnets to generate the required magnetic field is discussed. (G.T.H.)

  6. The introduction of clinical magnetic resonance imaging in Australia

    International Nuclear Information System (INIS)

    Sorby, W.; Baddeley, H.

    1986-01-01

    Magnetic resonance imaging is a new, but expensive, modality that is being introduced into clinical use in Australia. While it promises increased safety and accuracy in many situations, its precise role when compared with computed tomography and other modalities is not fully established. Therefore, a Government financed evaluation of costs and efficacy of magnetic resonance imaging units in five teaching hospitals is to be conducted over two years (1986-1988). Experience with the introduction of computed tomography to Australia and other nations has revealed difficulties in the evaluation by conventional methods of a diagnostic technology that is improving rapidly; it is to be hoped that a systematic evaluation of the clinical applications of magnetic resonance imaging will be more achievable and useful

  7. Magnetic resonance neurography for the identification of pudendal neuralgia

    Directory of Open Access Journals (Sweden)

    Claudia P. Cejas

    2017-06-01

    Full Text Available The pudendal nerve entrapment is an entity understudied by diagnosis imaging. Various causes are recognized in relation to difficult labors, rectal, perineal, urological and gynecological surgery, pelvic trauma fracture, bones tumors and compression by tumors or pelvic pseudotumors. Pudendal neuropathy should be clinically suspected, and confirmed by different methods such as electrofisiological testing: evoked potentials, terminal motor latency test and electromyogram, neuronal block and magnetic resonance imaging. The radiologist should be acquainted with the complex anatomy of the pelvic floor, particularly on the path of pudendal nerve studied by magnetic resonance imaging. High resolution magnetic resonance neurography should be used as a complementary diagnostic study along with clinical and electrophysiological examinations in patients with suspected pudendal nerve neuralgia.

  8. Studies of magnetic resonance in anemia of hematies falciformes

    International Nuclear Information System (INIS)

    Lores Guevara, Manuel Arsenio; Balcom, Bruce John; Cabal Mirabal, Carlos

    2012-01-01

    Magnetic Resonance applications to the study of Sickle Cell Disease are analyzed using classical procedures and Unilateral Magnetic Resonance. Hemoglobin and whole blood samples were obtained from healthy individual and patients with Sickle Cell Anemia to be used as samples. Classical pulse sequence as spin echo and inversion recovery were used in the experimental studies, the STEPR method was used for EPR spectrometric determinations. The results show the possibility of NMR methods to follow the molecular process causing the disease and allows to present quantitative procedures to estimate the clinical state of the patients and the results of clinical options. We present the Unilateral Magnetic Resonance as a new method to study Sickle Cell disease considering its portability and new possibilities as new image method

  9. 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.

  10. 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

  11. Magnetic resonance angiography vs. angiography in tetralogy of Fallot.

    Science.gov (United States)

    Rao, Uppalapati Venkateswara; Vanajakshamma, Velam; Rajasekhar, Durgaprasad; Lakshmi, Amancharla Yadagiri; Reddy, Reddivari Niranjan

    2013-08-01

    : To determine whether gadolinium-enhanced three-dimensional magnetic resonance angiography can provide a noninvasive alternative to diagnostic catheterization for evaluation of pulmonary artery anatomy in tetralogy of Fallot. Thirty-five consecutive patients with tetralogy of Fallot, who attended the cardiology outpatient department between January 2008 and December 2009, were included in the study. There were 21 males and 14 females, with a mean age of 9 ± 4.15 years (range, 3-21 years). Thirty-two patients had tetralogy of Fallot with varying severities of valvular and infundibular stenosis. Three patients had tetralogy of Fallot with pulmonary atresia. All patients underwent both cardiac catheterization with X-ray angiography and 3-dimensional magnetic resonance angiography within one month. Measurements of right and left pulmonary arteries and aortopulmonary collaterals were equal by both methods. There was a good correlation between magnetic resonance angiography and catheterization measurements of branch pulmonary arteries. Gadolinium-enhanced three-dimensional magnetic resonance angiography can be used as a reliable noninvasive alternative to X-ray cineangiography for delineation of pulmonary arterial anatomy in sick infants and young children, obviating the need for catheterization.

  12. Light-free magnetic resonance force microscopy for studies of electron spin polarized systems

    International Nuclear Information System (INIS)

    Pelekhov, Denis V.; Selcu, Camelia; Banerjee, Palash; Chung Fong, Kin; Chris Hammel, P.; Bhaskaran, Harish; Schwab, Keith

    2005-01-01

    Magnetic resonance force microscopy is a scanned probe technique capable of three-dimensional magnetic resonance imaging. Its excellent sensitivity opens the possibility for magnetic resonance studies of spin accumulation resulting from the injection of spin polarized currents into a para-magnetic collector. The method is based on mechanical detection of magnetic resonance which requires low noise detection of cantilever displacement; so far, this has been accomplished using optical interferometry. This is undesirable for experiments on doped silicon, where the presence of light is known to enhance spin relaxation rates. We report a non-optical displacement detection scheme based on sensitive microwave capacitive readout

  13. Magnetic resonance imaging-compatible tactile sensing device based on a piezoelectric array.

    Science.gov (United States)

    Hamed, Abbi; Masamune, Ken; Tse, Zion Tsz Ho; Lamperth, Michael; Dohi, Takeyoshi

    2012-07-01

    Minimally invasive surgery is a widely used medical technique, one of the drawbacks of which is the loss of direct sense of touch during the operation. Palpation is the use of fingertips to explore and make fast assessments of tissue morphology. Although technologies are developed to equip minimally invasive surgery tools with haptic feedback capabilities, the majority focus on tissue stiffness profiling and tool-tissue interaction force measurement. For greatly increased diagnostic capability, a magnetic resonance imaging-compatible tactile sensor design is proposed, which allows minimally invasive surgery to be performed under image guidance, combining the strong capability of magnetic resonance imaging soft tissue and intuitive palpation. The sensing unit is based on a piezoelectric sensor methodology, which conforms to the stringent mechanical and electrical design requirements imposed by the magnetic resonance environment The sensor mechanical design and the device integration to a 0.2 Tesla open magnetic resonance imaging scanner are described, together with the device's magnetic resonance compatibility testing. Its design limitations and potential future improvements are also discussed. A tactile sensing unit based on a piezoelectric sensor principle is proposed, which is designed for magnetic resonance imaging guided interventions.

  14. 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

  15. 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.)

  16. Vibration-synchronized magnetic resonance imaging for the detection of myocardial elasticity changes.

    Science.gov (United States)

    Elgeti, Thomas; Tzschätzsch, Heiko; Hirsch, Sebastian; Krefting, Dagmar; Klatt, Dieter; Niendorf, Thoralf; Braun, Jürgen; Sack, Ingolf

    2012-04-01

    Vibration synchronized magnetic resonance imaging of harmonically oscillating tissue interfaces is proposed for cardiac magnetic resonance elastography. The new approach exploits cardiac triggered cine imaging synchronized with extrinsic harmonic stimulation (f = 22.83 Hz) to display oscillatory tissue deformations in magnitude images. Oscillations are analyzed by intensity threshold-based image processing to track wave amplitude variations over the cardiac cycle. In agreement to literature data, results in 10 volunteers showed that endocardial wave amplitudes during systole (0.13 ± 0.07 mm) were significantly lower than during diastole (0.34 ± 0.14 mm, P magnetic resonance imaging improves the temporal resolution of magnetic resonance elastography as it overcomes the use of extra motion encoding gradients, is less sensitive to susceptibility artifacts, and does not suffer from dynamic range constraints frequently encountered in phase-based magnetic resonance elastography. Copyright © 2012 Wiley Periodicals, Inc.

  17. 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)

  18. 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)

  19. Limits to magnetic resonance microscopy

    International Nuclear Information System (INIS)

    Glover, Paul; Mansfield, Peter

    2002-01-01

    The last quarter of the twentieth century saw the development of magnetic resonance imaging (MRI) grow from a laboratory demonstration to a multi-billion dollar worldwide industry. There is a clinical body scanner in almost every hospital of the developed nations. The field of magnetic resonance microscopy (MRM), after mostly being abandoned by researchers in the first decade of MRI, has become an established branch of the science. This paper reviews the development of MRM over the last decade with an emphasis on the current state of the art. The fundamental principles of imaging and signal detection are examined to determine the physical principles which limit the available resolution. The limits are discussed with reference to liquid, solid and gas phase microscopy. In each area, the novel approaches employed by researchers to push back the limits of resolution are discussed. Although the limits to resolution are well known, the developments and applications of MRM have not reached their limit. (author)

  20. Magnetic resonance imaging of chemistry.

    Science.gov (United States)

    Britton, Melanie M

    2010-11-01

    Magnetic resonance imaging (MRI) has long been recognized as one of the most important tools in medical diagnosis and research. However, MRI is also well placed to image chemical reactions and processes, determine the concentration of chemical species, and look at how chemistry couples with environmental factors, such as flow and heterogeneous media. This tutorial review will explain how magnetic resonance imaging works, reviewing its application in chemistry and its ability to directly visualise chemical processes. It will give information on what resolution and contrast are possible, and what chemical and physical parameters can be measured. It will provide examples of the use of MRI to study chemical systems, its application in chemical engineering and the identification of contrast agents for non-clinical applications. A number of studies are presented including investigation of chemical conversion and selectivity in fixed-bed reactors, temperature probes for catalyst pellets, ion mobility during tablet dissolution, solvent dynamics and ion transport in Nafion polymers and the formation of chemical waves and patterns.