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- Björkman-Burtscher, Isabella, et al.
(författare)
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Aneurysm clip MR artifacts. Titanium versus stainless steel and influence of imaging parameters
- 1998
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Ingår i: Acta Radiologica. - 1600-0455. ; 39:1, s. 70-76
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Tidskriftsartikel (refereegranskat)abstract
- PURPOSE: The aim of this study was to evaluate the extent to which titanium aneurysm clips could improve the quality of MR imaging compared with stainless steel clips, and to determine whether the clip artifacts could be reduced by controlling certain MR imaging parameters in frequently used pulse sequences. MATERIAL AND METHODS: The metal artifacts induced by 3 aneurysm clips were compared in 3 pulse sequences. The clips were: a Yasargil titanium aneurysm clip FT 752 T; a Yasargil standard aneurysm clip FE 752 K; and, for comparison, a ferromagnetic Scoville aneurysm clip En-58J. The pulse sequences were: spin echo (SE); gradient echo (GE); and fast SE. An evaluation was made of 3 imaging parameters with regard to their influence on the size of the metal artifacts. The parameters were: bandwidth; echo time (TE); and echo-train length. RESULTS: The titanium clip showed artifacts that were about 60% smaller than those from the stainless steel clip. The only parameter that influenced artifact size to any major degree was bandwidth in the SE sequences but not in the GE sequences. GE sequences induced larger artifacts than SE sequences and showed larger artifacts with longer TE. CONCLUSION: Titanium aneurysm clips reduced MR artifacts by approximately 60% compared to stainless steel clips. Artifacts were further reduced by using SE-based sequences with a high bandwidth or, if necessary, GE sequences with a low TE.
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| 2. |
- Calamante, Fernando, et al.
(författare)
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MR System Operator: Recommended Minimum Requirements for Performing MRI in Human Subjects in a Research Setting
- 2015
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Ingår i: Journal of Magnetic Resonance Imaging. - : Wiley. - 1522-2586 .- 1053-1807. ; 41:4, s. 899-902
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Forskningsöversikt (refereegranskat)abstract
- This article is intended to provide guidelines for the minimum level of safety and operational knowledge that an MR system operator should exhibit in order to safely perform an MR procedure in a human subject in a research setting. This article represents the position of the International Society for Magnetic Resonance in Medicine (ISMRM) regarding this important topic and was developed by members of this society's MR Safety Committee. J. Magn. Reson. Imaging 2015;41:899-902. (c) 2014 Wiley Periodicals, Inc.
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| 3. |
- Hansson, Boel, et al.
(författare)
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MR-safety: Evaluation of compliance with screening routines using a structured screening interview
- 2022
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Ingår i: Journal of Patient Safety and Risk Management. - : SAGE Publications. - 2516-0435 .- 2516-0443. ; 27:2, s. 76-82
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Tidskriftsartikel (refereegranskat)abstract
- Background Magnetic resonance (MR) safety procedures are designed to allow patients, research subjects and personnel to enter the MR-scanner room under controlled conditions and without the risk to be harmed during the examination. Ferromagnetic objects in the MR-environment or inside the human body represent the main safety risks potentially leading to human injuries. Screening for MR-safety risks with dedicated procedures is therefore mandatory. As human errors during the screening procedure might align and lead to an incident compliance is essential. Purpose To evaluate compliance with a documented structured MR-safety screening process. Method Written and signed MR-safety screening documentation collected at a national 7T MR facility during a four-year period was evaluated for compliance of trained personnel with multi-step MR-safety routines. We analysed whether examinations were performed or why they were not performed. Data analysis further included descriptive statistics of the study population (age, gender and patient or healthy volunteer status), identification of missing documents and omitted or incorrect answers, and whether these compliance shortcomings concerned predominantly administrative or MR-safety related issues. Results Documentation of the screening process in 1819 subjects was incomplete in 19% of subjects. The most common documentation shortcoming was omitted fields. Out of 478 omitted answer-fields in 307 subjects, 36% were of administrative nature and 64% related directly to MR-safety issues. Conclusion Compliance with MR-safety screening procedures cannot be taken for granted and deficiencies to comply with screening routines were revealed. Documentation shortcomings concerned both administrative and MR-safety related issues.
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| 4. |
- Hansson, Boel, et al.
(författare)
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Subjectively Reported Effects Experienced in an Actively Shielded 7T MRI: A Large-Scale Study.
- 2020
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Ingår i: Journal of magnetic resonance imaging : JMRI. - : Wiley. - 1522-2586 .- 1053-1807. ; 52:4, s. 1265-1276
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Tidskriftsartikel (refereegranskat)abstract
- Ultrahigh-field (UHF) MRI advances towards clinical use. Patient compliance is generally high, but few large-scale studies have investigated the effects experienced in 7T MRI systems, especially considering peripheral nerve stimulation (PNS) and caregiving.To evaluate the quantity, the intensity, and subjective experiences from short-term effects, focusing on the levels of comfort and compliance of subjects.Prospective.In all, 954 consecutive MRIs in 801 subjects for 3years.7T.After the 7T examination, a questionnaire was used to collect data.Descriptive statistics, Spearman's rank correlation, Mann-Whitney U-test, and t-test.The majority (63%) of subjects agreed that the MRI experience was comfortable and 93% would be willing to undergo future 7T MRI as a patient (5% undecided) and 82% for research purposes (12% undecided). The most common short-term effects experienced were dizziness (81%), inconsistent movement (68%), PNS (63%), headache (40%), nausea (32%), metallic taste (12%), and light flashes (8%). Of the subjects who reported having PNS (n = 603), 44% experienced PNS as "not uncomfortable at all," 45% as "little or very little uncomfortable," and 11% as "moderate to very much uncomfortable." Scanner room temperature was experienced more comfortable before (78%) than during (58%) examinations, and the noise level was acceptable by 90% of subjects. Anxiety before the examination was reported by 43%. Patients differed from healthy volunteers regarding an experience of headache, metallic taste, dizziness, or anxiety. Room for improvement was pointed out after 117 examinations concerning given information (n = 73), communication and sound system (n = 35), or nursing care (n = 15).Subjectively reported effects occur in actively shielded 7T MRI and include physiological responses and individual psychological issues. Although leaving room for improvement, few subjects experienced these effects being so uncomfortable that they would lead to aversion to future UHF examinations.1 TECHNICAL EFFICACY: Stage 5.
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| 5. |
- Hansson, Boel, et al.
(författare)
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Swedish national survey on MR safety compared with CT : a false sense of security?
- 2020
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Ingår i: European Radiology. - : Springer Science and Business Media LLC. - 0938-7994 .- 1432-1084. ; 30:4, s. 1918-1926
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Tidskriftsartikel (refereegranskat)abstract
- Objectives: The objectives were to survey MR safety incidents in Sweden during a 12-month period, to assess severity scores, and to evaluate the confidence of MR personnel in incident-reporting mechanisms. Method: Data were collected within a web-based questionnaire on safety in clinical MR environments with CT for comparison. Data reported MR and CT safety incidents (human injury, material damage, and close calls), incident severity, and confidence of participants in incident-reporting systems. Results: The study population consisted of 529 eligible participants. Participants reported 200 MR and 156 CT safety incidents. Among MR incidents, 16% were given the highest potential severity score. More MR workers (73%) than CT workers (50%) were confident in being aware of any incident occurring at their workplace. However, 69% MR workers (83% for CT) were not aware of reported incidents at their hospitals. Conclusion: Safety incidents resulting in human injury, material damage, and close calls in clinical MR environments do occur. According to national risk assessment recommendations, risk level is high. Results indicated that MR personnel tend to a false sense of security, as a high proportion of staff members were sure that they would have been aware of any incident occurring in their own department, while in reality, incidents did occur without their knowledge. We conclude that false sense of security exists for MR. Key Points: • Safety incidents in clinical MR environments still result in human injury and material damage. • Severity level of MR incidents—assessed using Swedish national risk assessment recommendations—is high. • Confidence of MR personnel in incident-reporting mechanisms is high, but reflects a false sense of security, as a high proportion of staff is unaware of reported incidents in the same workplace.
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