59 research outputs found
Detection of Metabolites by Proton Ex Vivo NMR, in Vivo MR Spectroscopy Peaks and Tissue Content Analysis: Biochemical-Magnetic Resonance Correlation: Preliminary Results
*Aim*: Metabolite concentrations by in vivo magnetic resonance spectroscopy and ex vivo NMR spectroscopy were compared with excised normal human tissue relaxation times and tissue homogenate contents.

*Hypothesis*: Biochemical analysis combined with NMR and MR spectroscopy defines better tissue analysis.

*Materials and Methods*: Metabolites were measured using peak area, amplitude and molecular weights of metabolites in the reference solutions. In normal brain and heart autopsy, muscle and liver biopsy tissue ex vivo NMR peaks and spin-lattice (T1) and spin-spin (T2) relaxation times, were compared with diseased tissue NMR data in meningioma brain, myocardial infarct heart, duchene-muscular-dystrophy muscle and diffused-liver-injury liver after respective in vivo proton MR spectroscopy was done. NMR data was compared with tissue homogenate contents and serum levels of biochemical parameters.

*Results*: The quantitation of smaller NMR visible metabolites was feasible for both ex vivo NMR and in vivo MR spectroscopy. Ex vivo H-1 NMR and in vivo MRS metabolite characteristic peaks (disease/normal data represented as fold change), T1 and T2, and metabolites in tissue homogenate and serum indicated muscle fibrosis in DMD, cardiac energy depletion in MI heart, neuronal dysfunction in meningioma brain and carbohydrate-lipid metabolic crisis in DLI liver tissues.

*Conclusion*: This preliminary report highlights the biochemical-magnetic resonance correlation as basis of magnetic resonance spectroscopic imaging data interpretation of disease
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Radiology education in Europe: Analysis of results from 22 European countries.
AimTo assess the state of radiology education across Europe by means of a survey study.MethodsA comprehensive 23-item radiology survey was distributed via email to the International Society of Radiology members, national radiological societies, radiologists and medical physicists. Reminders to complete the survey were sent and the results were analyzed over a period of 4 mo (January-April 2016). Survey questions include length of medical school and residency training; availability of fellowship and subspecialty training; number of residency programs in each country; accreditation pathways; research training; and medical physics education. Descriptive statistics were used to analyze and summarize data.ResultsRadiology residency training ranges from 2-6 years with a median of 5 years, and follows 1 year of internship training in 55% (12 out of 22) European countries. Subspecialty fellowship training is offered in 55% (12 out of 22) European countries. Availability for specialization training by national societies is limited to eight countries. For nearly all respondents, less than fifty percent of radiologists travel abroad for specialization. Nine of 22 (41%) European countries have research requirements during residency. The types of certifying exam show variation where 64% (14 out of 22) European countries require both written and oral boards, 23% (5 out of 22) require oral examinations only, and 5% (1 out of 22) require written examinations only. A degree in medical physics is offered in 59% (13 out of 22) European countries and is predominantly taught by medical physicists. Nearly all respondents report that formal examinations in medical physics are required.ConclusionComparative learning experiences across the continent will help guide the development of comprehensive yet pragmatic infrastructures for radiology education and collaborations in radiology education worldwide
Current worldwide nuclear cardiology practices and radiation exposure: results from the 65 country IAEA Nuclear Cardiology Protocols Cross-Sectional Study (INCAPS)
Aims To characterize patient radiation doses from nuclear myocardial perfusion imaging (MPI) and the use of radiation-optimizing ‘best practices' worldwide, and to evaluate the relationship between laboratory use of best practices and patient radiation dose. Methods and results We conducted an observational cross-sectional study of protocols used for all 7911 MPI studies performed in 308 nuclear cardiology laboratories in 65 countries for a single week in March-April 2013. Eight ‘best practices' relating to radiation exposure were identified a priori by an expert committee, and a radiation-related quality index (QI) devised indicating the number of best practices used by a laboratory. Patient radiation effective dose (ED) ranged between 0.8 and 35.6 mSv (median 10.0 mSv). Average laboratory ED ranged from 2.2 to 24.4 mSv (median 10.4 mSv); only 91 (30%) laboratories achieved the median ED ≤ 9 mSv recommended by guidelines. Laboratory QIs ranged from 2 to 8 (median 5). Both ED and QI differed significantly between laboratories, countries, and world regions. The lowest median ED (8.0 mSv), in Europe, coincided with high best-practice adherence (mean laboratory QI 6.2). The highest doses (median 12.1 mSv) and low QI (4.9) occurred in Latin America. In hierarchical regression modelling, patients undergoing MPI at laboratories following more ‘best practices' had lower EDs. Conclusion Marked worldwide variation exists in radiation safety practices pertaining to MPI, with targeted EDs currently achieved in a minority of laboratories. The significant relationship between best-practice implementation and lower doses indicates numerous opportunities to reduce radiation exposure from MPI globall
Neuroelectric Evidence for Cognitive Association Formation: An Event-Related Potential Investigation
Although many types of learning require associations to be formed, little is known about the brain mechanisms engaged in association formation. In the present study, we measured event-related potentials (ERPs) while participants studied pairs of semantically related words, with each word of a pair presented sequentially. To narrow in on the associative component of the signal, the ERP difference between the first and second words of a pair (Word2-Word1) was derived separately for subsequently recalled and subsequently not-recalled pairs. When the resulting difference waveforms were contrasted, a parietal positivity was observed for subsequently recalled pairs around 460 ms after the word presentation onset, followed by a positive slow wave that lasted until around 845 ms. Together these results suggest that associations formed between semantically related words are correlated with a specific neural signature that is reflected in scalp recordings over the parietal region
Current worldwide nuclear cardiology practices and radiation exposure : results from the 65 country IAEA Nuclear Cardiology Protocols Cross-Sectional Study (INCAPS)
To characterize patient radiation doses from nuclear myocardial perfusion imaging (MPI) and the use of radiation-optimizing 'best practices' worldwide, and to evaluate the relationship between laboratory use of best practices and patient radiation dose. We conducted an observational cross-sectional study of protocols used for all 7911 MPI studies performed in 308 nuclear cardiology laboratories in 65 countries for a single week in March-April 2013. Eight 'best practices' relating to radiation exposure were identified a priori by an expert committee, and a radiation-related quality index (QI) devised indicating the number of best practices used by a laboratory. Patient radiation effective dose (ED) ranged between 0.8 and 35.6 mSv (median 10.0 mSv). Average laboratory ED ranged from 2.2 to 24.4 mSv (median 10.4 mSv); only 91 (30%) laboratories achieved the median ED ≤ 9 mSv recommended by guidelines. Laboratory QIs ranged from 2 to 8 (median 5). Both ED and QI differed significantly between laboratories, countries, and world regions. The lowest median ED (8.0 mSv), in Europe, coincided with high best-practice adherence (mean laboratory QI 6.2). The highest doses (median 12.1 mSv) and low QI (4.9) occurred in Latin America. In hierarchical regression modelling, patients undergoing MPI at laboratories following more 'best practices' had lower EDs. Marked worldwide variation exists in radiation safety practices pertaining to MPI, with targeted EDs currently achieved in a minority of laboratories. The significant relationship between best-practice implementation and lower doses indicates numerous opportunities to reduce radiation exposure from MPI globally
Evaluation of medical physics training in radiology residency in 67 countries
PURPOSE: The main aim of medical physics training in radiology residency is to have appropriate and safer imaging of patients and safety of personnel. The need to have adequate coverage of medical physics and radiation safety in curricula of radiology residency is well perceived, but it is not known how far it is implemented in practice. METHODS: We have analysed the data from 67 countries on medical physics teaching and assessment of residents in radiology programs, considering differences between countries in function of their human development index (HDI). RESULTS: The results indicate that teaching of medical physics by radiologists rather than by medical physicists is very common and there is relationship with the developmental status of a country. The majority of countries with very high HDI used a written test (69%) for medical physics topics, often in combination with other subjects (63%). Further, there is lack of direct involvement of medical physicists during the examination phase of residents. Geographically, it can be seen that Latin American countries in particular lack involvement of medical physicists during both the teaching and examination phase. CONCLUSION: The lack of adequate involvement of medical physicists in training and in the formal examination of radiology residents in both developed and developing countries is a matter of concern with likely implications on patient and staff safety.status: publishe
Data from: International Atomic Energy Agency survey study with referring physicians on patient radiation exposure and its tracking: A prospective survey using a web based questionnaire
OBJECTIVES: To assess the following themes among referring physicians: A. Importance of acquiring information about previous diagnostic exposures; B. Knowledge about radiation doses involved, familiarity with radiation units and, age related radiosensitivity; C. Opinion on whether patients should be provided information about radiation dose; and, D. Self-assessment of appropriateness of referrals. DESIGN: A prospective survey using a web based questionnaire. SETTING: International survey among referring physicians. PARTICIPANTS: Referring physicians from 28 countries. MAIN OUTCOME MEASURES: Knowledge, opinion and practice of the four themes of the survey. RESULTS: 728 responses from 28 countries (52.3% from developed and 47.7% from developing countries) indicated that while the vast majority (71.7%) of physicians feel that being aware of previous history of CT scans would always or mostly lead them to a better decision on referring patients for CT scans, only 43.4% often enquire about it. The majority of referring physicians (60.5%) stated that having a system that provides quick information about patient exposure history would be useful. The knowledge about radiation doses involved is poor, as only one-third (34.7%) of respondents chose the correct option of the number of chest x-rays with equivalence of a CT scan. 70.9% of physicians stated that they do not feel uncomfortable when patients ask about radiation risk from CT scans they prescribe. Most physicians (85.6%) assessed that they have rarely prescribed CT scans of no clinical use in patient management. CONCLUSIONS: This first ever multi-national survey among referring physicians from 28 countries indicates support for a system that provides radiation exposure history of the patient, demonstrates poor knowledge about radiation doses, supports radiation risk communication with patients and, mandatory provisions for justification of a CT examination
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