D. Kostova-Lefterova
University of Tartu
Interquartile rangePercentileRadiologyEffective dose (radiation)Latin AmericansTomographyAutomatic exposure controlKermaRadiological weaponMedical physicsReferralPneumoniaComputed tomography dose indexRadiologic examinationReference valuesStatistical analysisAge groupsExposure controlMulticenter studyAntiscatter gridCoronavirus disease 2019 (COVID-19)Disease severityX ray examinationDetailed dataIn patientPaediatric patientsPatient ageCt examinationAppropriate usePatient dataCt dose indexBody regionField sizeCurrent practiceDiagnostic qualityPediatric ctPatient doseRadiographyComputed tomographyImage qualityQuartileMedicineDeveloping country
Publications 6
#1Fatemeh Homayounieh (Harvard University)H-Index: 8
#2Ola Holmberg (IAEA: International Atomic Energy Agency)H-Index: 10
Last. Jenia VassilevaH-Index: 15
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Background There is lack of guidance on specific CT protocols for imaging patients with coronavirus disease 2019 (COVID-19) pneumonia. Purpose To assess international variations in CT utilization, protocols, and radiation doses in patients with COVID-19 pneumonia. Materials and Methods In this retrospective data collection study, the International Atomic Energy Agency (IAEA) coordinated a survey between May and July 2020 regarding CT utilization, protocols, and radiation doses from 62 healthcare...
9 CitationsSource
#1Jenia Vassileva (IAEA: International Atomic Energy Agency)H-Index: 15
#2Madan M. Rehani (Harvard University)H-Index: 32
Last. Areesha Zaman (Pakistan Atomic Energy Commission)H-Index: 5
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: The article reports results from the largest international dose survey in paediatric computed tomography (CT) in 32 countries and proposes international diagnostic reference levels (DRLs) in terms of computed tomography dose index (CTDI vol) and dose length product (DLP). It also assesses whether mean or median values of individual facilities should be used. A total of 6115 individual patient data were recorded among four age groups: 1-5 y, >5-10 y and >10-15 y. CTDIw, CTDI vol and DLP from th...
32 CitationsSource
#2D. TasevaH-Index: 3
Last. Jenia VassilevaH-Index: 15
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The purpose of this work is to present the algorithm for the optimisation of paediatric chest radiographyaimed to reduce patientdoses at keeping adequate image quality. Optimal tube voltage, tube current and exposure time, use of automatic or manual ex-posure control anduseof antiscattergridwere recommended fordifferentagegroupsanddependingon thepatient size.The opti-mised protocols and radiography technique resulted in decrease in Entrance surface air kerma and effective dose values in afactoro...
6 CitationsSource
#1Jenia VassilevaH-Index: 15
#2Madan M. Rehani (IAEA: International Atomic Energy Agency)H-Index: 32
Last. Dejan ZontarH-Index: 2
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OBJECTIVE. The purpose of this study was to assess the frequency of pediatric CT in 40 less-resourced countries and to determine the level of appropriateness in CT use. MATERIALS AND METHODS. Data on the increase in the number of CT examinations during 2007 and 2009 and appropriate use of CT examinations were collected, using standard forms, from 146 CT facilities at 126 hospitals. RESULTS. The lowest frequency of pediatric CT examinations in 2009 was in European facilities (4.3%), and frequenci...
38 CitationsSource
The purpose of this study was to explore the frequency of paediatric computed tomography (CT) examinations in several hospitals in Bulgaria and to assess the current practice. The standard forms provided by the International Atomic Emergency Agency for survey of the paediatric CT practice were used. Six hospitals provided data on frequency of paediatric CT examinations performed in 2009. Large variations in dose, up to a factor of 4, were found among the centres within the same age group for a g...
4 CitationsSource
#2D. TasevaH-Index: 3
Last. Jenia VassilevaH-Index: 15
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The purpose of this study was to compare the important aspects of paediatric radiological practice and the patient doses fromchest X-ray examinations performed in three hospitals in Bulgaria. Data from 163 paediatric patients were recorded using astandardised form. Entrance surface air kerma (ESAK) to patient was calculated from the air-kerma air product (KAP) andfield size measurements. Large variations were found for KAP and ESAK. Inappropriate film size and insufficient collimationwere often use...
3 CitationsSource