12 results on '"Simona Avramova-Cholakova"'
Search Results
2. PERFORMANCE COMPARISON OF SYSTEMS WITH FULL-FIELD DIGITAL MAMMOGRAPHY, DIGITAL BREAST TOMOSYNTHESIS AND CONTRAST-ENHANCED SPECTRAL MAMMOGRAPHY
- Author
-
Simona Avramova-Cholakova, Eugenia Kulama, Sivo Daskalov, and John Loveland
- Subjects
Radiographic Image Enhancement ,Radiation ,Radiological and Ultrasound Technology ,Public Health, Environmental and Occupational Health ,Humans ,Radiology, Nuclear Medicine and imaging ,Breast Neoplasms ,Female ,General Medicine ,Breast ,Radiation Dosage ,Radiometry ,Mammography - Abstract
The purpose is to compare full-field digital mammography (FFDM), digital breast tomosynthesis (DBT) and contrast-enhanced spectral mammography (CESM) technologies on three mammography systems in terms of image quality and patient dose. Two Senographe Essential with DBT and CESM (denoted S1 and S2) and one Selenia Dimensions (S3) with FFDM and DBT were considered. Dosimetry methods recommended in the European protocol were used. Image quality was tested with CDMAM in FFDM and DBT and with ideal observer method in FFDM. Mean values of mean glandular dose (MGD) from whole patient samples on S1, S2 and S3 were as follows: FFDM 1.65, 1.84 and 2.23 mGy; DBT 2.03, 1.96 and 2.87 mGy; CESM 2.65 and 3.16 mGy, respectively. S3 exhibited better low-contrast detectability for the smallest sized discs of CDMAM and ideal observer in FFDM, and for the largest sized discs in DBT, at similar dose levels.
- Published
- 2021
3. Use of Multiphase CT Protocols in 18 Countries: Appropriateness and Radiation Doses
- Author
-
Doris Šegota, Ana Diklić, Riddhi Borse, Jenia Vassileva, Slaven Jurković, Huda Al-Naemi, Antar Ali, Mannudeep K. Kalra, Ili Majidah Binti Hj Zulkipli, Petra Valković Zujić, Madan M. Rehani, Jokha Alkalbani, Nilar Shein, Vesna Gershan, Mohammad Yusuf, Amaal Al-Rasbi, Shivam Rastogi, Seife Teferi, Hassan Mohammed Kharita, Simona Avramova-Cholakova, Ramandeep Singh, and Stipe Galić
- Subjects
Adult ,Male ,Asia ,Computed tomography ,Thoracic Cavity ,Radiation ,Unnecessary Procedures ,Radiation Dosage ,BIOMEDICINE AND HEALTHCARE. Clinical Medical Sciences. Radiology ,030218 nuclear medicine & medical imaging ,Ct chest ,Pelvis ,03 medical and health sciences ,0302 clinical medicine ,Clinical Protocols ,Surveys and Questionnaires ,Abdomen ,Medicine ,Humans ,Radiology, Nuclear Medicine and imaging ,multiphase scanning ,CT chest ,CT abdomen–pelvis ,radiation dose ,justification ,medicine.diagnostic_test ,business.industry ,Diagnostic Tests, Routine ,Radiation dose ,General Medicine ,NATURAL SCIENCES. Physics ,Europe ,PRIRODNE ZNANOSTI. Fizika ,030220 oncology & carcinogenesis ,Africa ,Female ,Radiography, Thoracic ,business ,Nuclear medicine ,Tomography, X-Ray Computed ,BIOMEDICINA I ZDRAVSTVO. Kliničke medicinske znanosti. Radiologija - Abstract
Purpose: To assess the frequency, appropriateness, and radiation doses associated with multiphase computed tomography (CT) protocols for routine chest and abdomen–pelvis examinations in 18 countries. Materials and Methods: In collaboration with the International Atomic Energy Agency, multi-institutional data on clinical indications, number of scan phases, scan parameters, and radiation dose descriptors (CT dose–index volume; dose–length product [DLP]) were collected for routine chest (n = 1706 patients) and abdomen–pelvis (n = 426 patients) CT from 18 institutions in Asia, Africa, and Europe. Two radiologists scored the need for each phase based on clinical indications (1 = not indicated, 2 = probably indicated, 3 = indicated). We surveyed 11 institutions for their practice regarding single-phase and multiphase CT examinations. Data were analyzed with the Student t test. Results: Most institutions use multiphase protocols for routine chest (10/18 institutions) and routine abdomen–pelvis (10/11 institutions that supplied data for abdomen–pelvis) CT examinations. Most institutions (10/11) do not modify scan parameters between different scan phases. Respective total DLP for 1-, 2-, and 3-phase routine chest CT was 272, 518, and 820 mGy·cm, respectively. Corresponding values for 1- to 5-phase routine abdomen–pelvis CT were 400, 726, 1218, 1214, and 1458 mGy cm, respectively. For multiphase CT protocols, there were no differences in scan parameters and radiation doses between different phases for either chest or abdomen–pelvis CT ( P = 0.40-0.99). Multiphase CT examinations were unnecessary in 100% of routine chest CT and in 63% of routine abdomen–pelvis CT examinations. Conclusions: Multiphase scan protocols for the routine chest and abdomen–pelvis CT examinations are unnecessary, and their use increases radiation dose.
- Published
- 2020
4. CT protocols and radiation doses for hematuria and urinary stones: Comparing practices in 20 countries
- Author
-
Graciano Paulo, Vesna Gershan, Andrej Klepanec, Olga Girjoaba, E. Georgiev, Darka Hadnadjev Šimonji, Aleksandra Milatović, Birute Griciene, S A Kharuzhyk, Edward Gruppetta, Fatemeh Homayounieh, Jenia Vassileva, Anna Kulikova, Simona Avramova-Cholakova, Ramandeep Singh, Dario Faj, Ivan Lasić, Mannudeep K. Kalra, Desisslava Kostova-Lefterova, Andrej Klepanec, Fatemeh Homayounieh, Birute Griciene, Simona Avramova-Cholakova, Dario Faj, Graciano Paulo, Birute Mrs Griciene, Vesna Gershan, Siarhei Kharuzhyk, and Desislava Kostova-Lefterova
- Subjects
Adult ,Male ,medicine.medical_specialty ,Urinary system ,Ct urography ,Radiation Dosage ,030218 nuclear medicine & medical imaging ,Radiation dosage ,03 medical and health sciences ,0302 clinical medicine ,medicine ,Humans ,Low dose ct ,Radiology, Nuclear Medicine and imaging ,Renal colic ,Urinary Tract ,Computed tomography ,Hematuria ,Protocol (science) ,Urinary Stone ,business.industry ,Clinical protocols ,Radiation dose ,Urography ,General Medicine ,Middle Aged ,Appropriateness criteria ,Computed Tomography ,Radiation Dose ,Clinical Protocols ,030220 oncology & carcinogenesis ,Female ,Urinary Calculi ,Radiology ,medicine.symptom ,Tomography, X-Ray Computed ,business ,Pyelogram - Abstract
Purpose Patients with hematuria and renal colic often undergo CT scanning. The purpose of our study was to assess variations in CT protocols and radiation doses for evaluation of hematuria and urinary stones in 20 countries. Method The International Atomic Energy Agency (IAEA) surveyed practices in 51 hospitals from 20 countries in the European region according to the IAEA Technical cooperation classification and obtained following information for three CT protocols (urography, urinary stones, and routine abdomen-pelvis CT) for 1276 patients: patient information (weight, clinical indication), scanner information (scan vendor, scanner name, number of detector rows), scan parameters (such as number of phases, scan start and end locations, mA, kV), and radiation dose descriptors (CTDIvol, DLP). Two radiologists assessed the appropriateness of clinical indications and number of scan phases using the ESR Referral Guidelines and ACR Appropriateness Criteria. Descriptive statistics and Student’s t tests were performed. Results Most institutions use 3-6 phase CT urography protocols (80%, median DLP 1793-3618 mGy.cm) which were associated with 2.4-4.9-fold higher dose compared to 2-phase protocol (20%, 740 mGy.cm) (p < 0.0001). Likewise, 52% patients underwent 3-5 phase routine abdomen- pelvis CT (1574-2945 mGy.cm) as opposed to 37% scanned with a single-phase routine CT (676 mGy.cm). The median DLP for urinary stones CT (516 mGy.cm) were significantly lower than the median DLP for the other two CT protocols (p < 0.0001). Conclusions Few institutions (4/13) use low dose CT for urinary stones. There are substantial variations in CT urography and routine abdomen- pelvis CT protocols result in massive radiation doses (up to 2945-3618 mGy.cm).
- Published
- 2020
- Full Text
- View/download PDF
5. Quality Controls in Digital Mammography protocol of the EFOMP Mammo Working group
- Author
-
Andrea Azzalini, Olivera Ciraj, Alberto Torresin, Gisella Gennaro, Margarita Chevalier, Kristin Pedersen, Elizabeth Keavey, Mário João Fartaria, Bengt Hemdal, Maria Luisa Chapel, Veronica Rossetti, Stefano Rivetti, Hugo de las Heras, Susanne Menhart, Nico Lanconelli, Ana Pascoal, Peter F. Sharp, Simona Avramova-Cholakova, Friedrich Semturs, Vesna Gershan, Gennaro G, Avramova-Cholakova S, Azzalini A, Luisa Chapel M, Chevalier M, Ciraj O, de las Heras H, Gershan V, Hemdal B, Keavey E, Lanconelli N, Menhart S, João Fartaria M, Pascoal A, Pedersen K, Rivetti S, Rossetti V, Semturs F, Sharp P, and Torresin A
- Subjects
Societies, Scientific ,Digital mammography ,Quality Assurance, Health Care ,Computer science ,media_common.quotation_subject ,Control (management) ,Biophysics ,General Physics and Astronomy ,computer.software_genre ,Radiation Dosage ,030218 nuclear medicine & medical imaging ,Medical physicist ,Set (abstract data type) ,03 medical and health sciences ,0302 clinical medicine ,Software ,EFOMP ,digital mammography ,Protocol ,Humans ,Radiology, Nuclear Medicine and imaging ,Quality (business) ,protocol ,quality control ,media_common ,Protocol (science) ,Multimedia ,business.industry ,Quality control ,General Medicine ,Radiation Exposure ,Full Protocol ,030220 oncology & carcinogenesis ,business ,computer ,Mammography - Abstract
This article aims to present the protocol on Quality Controls in Digital Mammography published online in 2015 by the European Federation of Organisations for Medical Physics (EFOMP) which was developed by a Task Force under the Mammo Working Group. The main objective of this protocol was to define a minimum set of easily implemented quality control tests on digital mammography systems that can be used to assure the performance of a system within a set and acceptable range. Detailed step-by-step instructions have been provided, limiting as much as possible any misinterpretations or variations by the person performing. It is intended that these tests be implemented as part of the daily routine of medical physicists and system users throughout Europe in a harmonised way so allowing results to be compared. In this paper the main characteristics of the protocol are illustrated, including examples, together with a brief summary of the contents of each chapter. Finally, instructions for the download of the full protocol and of the related software tools are provided.
- Published
- 2018
6. Patient exposures from three different modalities on one mammography unit
- Author
-
Simona Avramova-Cholakova and Eugenia Kulama
- Subjects
Biophysics ,General Physics and Astronomy ,Radiology, Nuclear Medicine and imaging ,General Medicine - Published
- 2019
- Full Text
- View/download PDF
7. Comparative study of patient doses on four CT scanners
- Author
-
Simona Avramova-Cholakova and Eugenia Kulama
- Subjects
Biophysics ,General Physics and Astronomy ,Radiology, Nuclear Medicine and imaging ,General Medicine - Published
- 2019
- Full Text
- View/download PDF
8. Criteria for acquiring and maintaining the title 'Medical Physics Expert' in Bulgaria
- Author
-
Simona Avramova-Cholakova
- Subjects
medicine.medical_specialty ,Emerging technologies ,Biophysics ,Specialty ,General Physics and Astronomy ,Medical practice ,Legislation ,General Medicine ,language.human_language ,Medical physicist ,Continuing professional development ,Political science ,medicine ,language ,media_common.cataloged_instance ,Radiology, Nuclear Medicine and imaging ,Medical physics ,Bulgarian ,European union ,media_common - Abstract
The Council Directive 2013/59/EURATOM requires medical physics experts (MPE) to be recognized at governmental level and their continuity of expertise to be ensured. In 2014 European Guidelines on Medical Physics Expert, Radiation Protection No 174 (RP174) was published. This document provides comprehensive description of educational and training schemes, as well as knowledge, skills and competences that should be possessed by MPE. As of 2005 Bulgarian ordinance was issued, harmonizing Bulgarian legislation with the requirements of the European Union, stating the role of MPE in medical practice. According to this document a physicist should have Medical Radiological Physics specialty and five years of professional experience in some of the fields of medical physics, in order to become MPE. In 2018 modification of the ordinance required implementation of a scheme for continuous professional development (CPD) of MPE. The Bulgarian Society of Biomedical Physics and Engineering is responsible to elaborate guidelines for CPD. A working group (WG) with representatives from all areas (radiation therapy, diagnostic radiology and nuclear medicine) and with experience in education and training was created for that purpose. The WG prepared a draft of guidelines for CPD based on RP174 and EFOMP Policy Statement No. 10.1: Recommended Guidelines on National Schemes for Continuing Professional Development of Medical Physicists. According to the prepared guidelines the MPE is recognized separately in each of the three fields. Credit points are assigned for activities related to education, practical or scientific activities, lecturing and publications. Educational activities include participation in courses, lectures, conferences, defense of PhD, etc. Practical or scientific activities are participation in projects, introduction of new technologies, development of new methods, elaboration of technical protocols, conduction of educational activities at the working place, visits of other hospitals and others. A total of 250 credit points must be collected for a 5 years period.
- Published
- 2019
- Full Text
- View/download PDF
9. Image quality and dose in mammography in 17 countries in Africa, Asia and Eastern Europe: Results from IAEA projects
- Author
-
Samuel Oola, W. E. Muhogora, Julius Ziliukas, Ion Ursulean, S. Economides, Cyril Schandorf, I.R. Videnović, Edward Grupetta, Mohammad Hassan Kharita, Saeid Setayeshi, Vesna Gershan, Milomir Milakovic, Olivera Ciraj-Bjelac, Pirunthavany Muthuvelu, Constantin Milu, Dario Faj, Areesha Zaman, Simona Avramova-Cholakova, Adnan Beganović, and Madan M. Rehani
- Subjects
medicine.medical_specialty ,Asia ,Scoring system ,Quality Assurance, Health Care ,Image quality ,media_common.quotation_subject ,Radiography ,Population ,Radiation Dosage ,Sensitivity and Specificity ,030218 nuclear medicine & medical imaging ,03 medical and health sciences ,0302 clinical medicine ,Image Interpretation, Computer-Assisted ,medicine ,Humans ,Mammography ,Radiology, Nuclear Medicine and imaging ,Quality (business) ,Medical physics ,Europe, Eastern ,Radiometry ,education ,media_common ,education.field_of_study ,medicine.diagnostic_test ,business.industry ,Radiation dose ,QA mammography ,Reproducibility of Results ,General Medicine ,mammography ,image quality ,radiation dose ,QA ,030220 oncology & carcinogenesis ,Africa ,Practice Guidelines as Topic ,business ,Quality assurance - Abstract
Purpose: The objective is to study mammography practice from an optimisation point of view by assessing the impact of simple and immediately implementable corrective actions on image quality. Materials and methods: This prospective multinational study included 54 mammography units in 17 countries. More than 21,000 mammography images were evaluated using a three-level image quality scoring system. Following initial assessment, appropriate corrective actions were implemented and image quality was re-assessed in 24 units. Results: The fraction of images that were considered acceptable without any remark in the first phase (before the implementation of corrective actions) was 70% and 75% for cranio-caudal and medio-lateral oblique projections, respectively. The main causes for poor image quality before corrective actions were related to film processing, damaged or scratched image receptors, or film-screen combinations that are not spectrally matched, inappropriate radiographic techniques and lack of training. Average glandular dose to a standard breast was 1.5mGy (mean and range 0.59-3.2 mGy). After optimisation the frequency of poor quality images decreased, but the relative contributions of the various causes remained similar. Image quality improvements following appropriate corrective actions were up to 50 percentage points in some facilities. Conclusions: Poor image quality is a major source of unnecessary radiation dose to the breast. An increased awareness of good quality mammograms is of particular importance for countries that are moving towards introduction of population-based screening programmes. The study demonstrated how simple and low-cost measures can be a valuable tool in improving of image quality in mammography. (C) 2011 Elsevier Ireland Ltd. All rights reserved.
- Published
- 2012
- Full Text
- View/download PDF
10. Pilot study of patient and phantom breast dose measurements in Bulgaria
- Author
-
Simona Avramova-Cholakova and Jenia Vassileva
- Subjects
medicine.diagnostic_test ,business.industry ,Biophysics ,Dose profile ,equipment and supplies ,Imaging phantom ,Medicine ,Dosimetry ,Mammography ,Radiology, Nuclear Medicine and imaging ,Patient dose ,Mammography screening ,business ,Nuclear medicine ,Phantom studies - Abstract
Pilot study of patient and phantom breast dose measurements in Bulgaria A pilot study of breast dose measurements on two mammography units in Bulgaria was conducted. The mean glandular doses (MGDs) to samples of approximately 60 women per unit were measured. MGD with a standard PMMA phantom was measured as well. The MGDs were calculated according to the European protocol on dosimetry in mammography as well as to the European protocol for the quality control of the physical and technical aspects of mammography screening. The measured women's MGDs were divided into three groups depending on the compressed breast thicknesses. The results for the group of thicknesses in the interval 40-60 mm were compared with the results from the measurements on the standard 45 mm PMMA phantom. Some differences were found which could be due to errors in breast thickness measurements, differences in breast and phantom densities and other factors. A standardized procedure was elaborated for patient dose measurement and calculation both from patient and phantom studies.
- Published
- 2008
- Full Text
- View/download PDF
11. Comparison of different dosimetry methods for 64-row detector computed tomography
- Author
-
Jenia Vassileva, I. Dyakov, D. Kostova-Lefterova, Simona Avramova-Cholakova, and M. Gancheva
- Subjects
Physics ,medicine.diagnostic_test ,business.industry ,Detector ,Biophysics ,General Physics and Astronomy ,Computed tomography ,General Medicine ,medicine ,Dosimetry ,Radiology, Nuclear Medicine and imaging ,Nuclear medicine ,business ,Image-guided radiation therapy - Published
- 2014
- Full Text
- View/download PDF
12. National survey in diagnostic radiology in Bulgaria 2007-2009
- Author
-
Vassileva, J., Borisova, R., Stoyanov, D., Dimov, A., Simona Avramova-Cholakova, Ingilizova, K., Kostova-Lefterova, D., Hristova-Popova, J., Diakov, I., Taseva, D., and Dosieva, D.
Catalog
Discovery Service for Jio Institute Digital Library
For full access to our library's resources, please sign in.