62 research outputs found
Evaluation of Diffusion Tensor Imaging Findings in Clinically Isolated Syndrome and Relapsing-Remitting Multiple Sclerosis Patients
Objective: To compare diffusion tensor imaging (DTI) findings of the normal-appearing white matter (NAWM) and corpus callosum (CC) in patients with clinically isolated syndrome (CIS) and relapsing-remitting multiple sclerosis (RRMS) and a healthy control (HC) group. Materials and Methods: The CIS (n = 10), RRMS (n = 29), and HC (n = 13) groups were evaluated by DTI in this retrospective study. Mean diffusion (MD) and fractional anisotropy (FA) maps as well as MD and FA measurements were made from the corpus callosum genu (CCG), corpus callosum splenium (CCS), and NAWM areas from the frontal, parietal, occipital and temporal lobes. Results: The mean FA values of the NAWM in the temporal lobes were bilaterally lower in both the CIS and RRMS groups than in the HC group. However, no difference was found between the CIS and RRMS groups. In addition, the CIS group had lower FA values in the CCG, whereas the RRMS group had lower FA values in the CCS compared with the HC group. The MD values were significantly different in the CCG between the RRMS and HC groups. Conclusion: DTI contributes to detecting early changes in the NAWM and CC in patients diagnosed with CIS and RRMS. Additionally, DTI can aid in the follow-up care and management of these patients
Monte carlo simulation of radiation of the beta emitting sources in a magnetic field
Amaç: Beta yayan radyoizotoplarla yapılan kanser tedavilerinde manyetik alan kullanılarak normal dokulara olan zararın azaltılmasının mümkün olabileceği varsayımı ile Monte Carlo tabanlı Geant4 simülasyon programı kullanılarak beta parçacıklarının manyetik alandaki davranışları araştırıldı. Gereç ve Yöntem: Geant4 programında radyasyonun dedekte edileceği içi su dolu küresel bir ortam oluşturuldu ve merkezine beta parçacıklarının tek enerjili ve rastgele fırlatılacağı parçacık kaynağı yerleştirildi. x yönünde homojen manyetik alan uygulanarak, kürenin merkezinden parçacığın menziline göre y ekseninde kesitler oluşturuldu. Farklı büyüklükteki manyetik alanlarda (0-3 Tesla), farklı enerjilerdeki (0,5-2 MeV) beta parçacıkları için elde edilen veriler, Matlab programında her kesitteki parçacıkların yaptıkları etkileşim sayıları hesaplanarak analiz edildi. Bulgular: Kaynaktan çıkan beta parçacığının menzilinin enerjisiyle doğru orantılı olarak arttığı görüldü. Maksimum beta parçacığı menzili 0,5, 1, 1,5 ve 2 MeV enerjili beta için sırasıyla yaklaşık olarak 1,5, 4, 6 ve 8 mm bulundu. Merkezden uzaklaştıkça etkileşim sayısında eksponansiyel olarak düşüş olduğu bulundu. Manyetik alan artmasıyla beraber merkezde etkileşim sayısında artma olduğu, merkezin dışında ise etkileşim sayısının manyetik alanla ters orantılı olarak azaldığı görüldü. Manyetik alana dik yöndeki değişim manyetik alana paralel yöndekine göre daha fazladır. Sonuç: Beta parçacıklarının manyetik alanda dairesel hareket ederek ilerlediği ve manyetik alanın artmasıyla menzillerinin kısaldığı gözlendi. Nokta kaynaktan rastgele yönlerde çıkan beta parçacıklarının ortamda küresel geometride, manyetik alanda ise eliptik olarak dağıldığı bulundu. Manyetik alan arttıkça, manyetik alana dik yönlerde merkezden dışa doğru etkileşim sayısındaki azalım daha belirgin olmaktadır. Manyetik alan etkisinin düşük enerjililere oranla yüksek enerjili beta parçacıklarında daha belirgin olduğu görüldü. Anahtar Sözcükler: Beta radyasyonu, manyetik alan, Monte Carlo Simülasyonu, Geant4 Purpose: Following the assumption of reducing the damage to the normal tissues using magnetic field in the cancer treatment carried out by beta-emitting radioisotopes behaviour of beta particles under the magnetic field was investigated with Greant4 simulation program with Monte Carlo basis. Material and Methods: A water-filled spherical medium in which radiation would be detected was formed in Greant4 program and a particle source, in which beta particles had single energies and would be launched randomly, was placed into its center. After applying a homogenous magnetic field in the x direction, cross-sections were formed in the y axis according to the range of the particle from the center of the sphere. In magnetic fields of different magnitudes (0-3 Tesla), the data obtained for beta particles of different energies (0,5-2 MeV) were analyzed counting the interaction numbers of the particles in each cross section by Matlab program. Results: The range of the beta particle from the source was observed to increase in direct proportion to its energy. Maximum ranges of the beta particles are approximately 1,5, 4, 6 and 8 mm for betas with 0,5, 1, 1,5 and 2 MeV respectively. Interaction number decreased exponentially further away from the center. With the increase of the magnetic field, the interaction number at the center was increased, but the interaction number decreased the center inversely proportional to magnetic field. The change perpendicular to the magnetic field is greater compared to parallel to the magnetic field. Conclusion: Beta particles were observed to go forward with circular moves in the magnetic field and to have their range shortened when magnetic field is increased. It was found that beta particles from the point source scattered to random directions spherically in the medium and the geometry became elliptical in magnetic field. When magnetic field increases, the change towards the center becomes more pronounced in perpendicular directions to magnetic field. The effect of magnetic field was more explicit for beta particles with high energies than these with low energies. Key words: Beta radiation, magnetic field, Monte Carlo Simulation, Geant
Evaluation of Awareness on Radiation Protection and Knowledge About Radiological Examinations in Healthcare Professionals Who Use Ionized Radiation at Work
Objective: In this study, we evaluated the knowledge and perception and mitigation of hazards involved in radiological examinations,
focusing on healthcare personnel who are not in radiation-related occupations, but who use ionising radiation as a part of their work.
Methods: A questionnaire was applied to physicians, nurses, technicians and other staff working in different clinics that use radiation
in their work, in order to evaluate their knowledge levels about ionizing radiation and their awareness about radiation doses resulting
from radiological examinations. The statistical comparisons between the groups were analyzed with the Kruskal Wallis test using the
SPSS program.
Results: Ninety two participants took part in the study. Their level of knowledge about ionizing radiation and doses in radiological
examinations were found to be very weak. The number of correct answers of physicians, nurses, medical technicians and other
personnel groups were 15.7±3.7, 13.0±4.0, 10.1±2.9 and 11.8±4.0, respectively. In the statistical comparison between the groups,
the level of knowledge of physicians was found to be significantly higher than the level of the other groups (p=0.005).
Conclusion: The present study demonstrated that general knowledge in relation to radiation, radiation protection, health risks and
doses used for radiological applications are insufficient among health professions using with ionizing radiation in their work
EVALUATİON OF GRAY MATTER ATROPHY İN MİLDCOGNİTİVEİMPAİRMENT: A VOXEL-BASED MORPHOMETRİC ANALYSİS
Evaluation of Awareness on Radiation Protection and Knowledge About Radiological Examinations in Healthcare Professionals Who Use Ionized Radiation at Work
Objective: In this study, we evaluated the knowledge and perception and mitigation of hazards involved in radiological examinations,
focusing on healthcare personnel who are not in radiation-related occupations, but who use ionising radiation as a part of their work.
Methods: A questionnaire was applied to physicians, nurses, technicians and other staff working in different clinics that use radiation
in their work, in order to evaluate their knowledge levels about ionizing radiation and their awareness about radiation doses resulting
from radiological examinations. The statistical comparisons between the groups were analyzed with the Kruskal Wallis test using the
SPSS program.
Results: Ninety two participants took part in the study. Their level of knowledge about ionizing radiation and doses in radiological
examinations were found to be very weak. The number of correct answers of physicians, nurses, medical technicians and other
personnel groups were 15.7±3.7, 13.0±4.0, 10.1±2.9 and 11.8±4.0, respectively. In the statistical comparison between the groups,
the level of knowledge of physicians was found to be significantly higher than the level of the other groups (p=0.005).
Conclusion: The present study demonstrated that general knowledge in relation to radiation, radiation protection, health risks and
doses used for radiological applications are insufficient among health professions using with ionizing radiation in their work
Volumetric magnetic resonance imaging differences between complex febrile seizure and recurrent simple febrile seizure
Purpose: We investigated the volumetric differences in cortical and subcortical structures between patients with complex febrile seizure (FS) and recurrent simple FS. We aimed to identify the brain morphological patterns of children with complex FS. Methods: Twenty-five patients with complex FS and age- and sex-matched 25 patients with recurrent simple FS with structural magnetic resonance imaging (MRI) scans were studied. Cortical volumetric analysis was performed using a voxel-based morphometry method with the CAT12 toolbox within SPM12. FSL-FIRST was used to obtain volume measures of subcortical deep grey matter structures (amygdala, caudate nucleus, thalamus, nucleus accumbens, putamen, globus pallidus, and hippocampus). The volumetric asymmetry index (AI) and laterality index (LI) were calculated for each subcortical structure. Results: Compared with recurrent simple FS, complex FS demonstrated lower volume in the left putamen (p = .003) and right nucleus accumbens (p = .001). Additionally, patients with complex FS presented a higher magnitude of AI of the nucleus accumbens (p < .001) compared with recurrent simple FS. Conclusions: The findings indicate that volumetric analysis may be a useful marker for the detection of FS-induced changes that reflect microstructural alterations. This study is the first to report on alterations in the putamen and nucleus accumbens in FS
Difüzyon Tensör Görüntüleme ile Hafif Kognitif Bozukluk Hastalarında Saptanan Beyaz Cevher Anormalliklerinin TBSS ile Değerlendirilmesi
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