دورية أكاديمية

Evaluation of the imaging properties of two generations of a CCD-based system for digital chest radiography.

التفاصيل البيبلوغرافية
العنوان: Evaluation of the imaging properties of two generations of a CCD-based system for digital chest radiography.
المؤلفون: Båth M; Department of Radiation Physics, Goteborg University, Sweden. magnus.bath@radfys.gu.se, Sund P, Månsson LG
المصدر: Medical physics [Med Phys] 2002 Oct; Vol. 29 (10), pp. 2286-97.
نوع المنشور: Journal Article; Research Support, Non-U.S. Gov't
اللغة: English
بيانات الدورية: Publisher: John Wiley and Sons, Inc Country of Publication: United States NLM ID: 0425746 Publication Model: Print Cited Medium: Print ISSN: 0094-2405 (Print) Linking ISSN: 00942405 NLM ISO Abbreviation: Med Phys Subsets: MEDLINE
أسماء مطبوعة: Publication: 2017- : Hoboken, NJ : John Wiley and Sons, Inc.
Original Publication: Lancaster, Pa., Published for the American Assn. of Physicists in Medicine by the American Institute of Physics.
مواضيع طبية MeSH: Radiographic Image Enhancement* , X-Rays*, Radiography, Thoracic/*instrumentation , Radiography, Thoracic/*methods, Equipment Design ; Models, Statistical ; Models, Theoretical ; Photons ; Scattering, Radiation ; Technology, Radiologic
مستخلص: Two generations of a CCD-based detector system with lens-based optical coupling for digital chest radiography were evaluated in terms of presampling MTF, NPS, NEQ, DQE, linearity in response, and SNR over the detector area. Measurements were performed over a wide exposure range and at several different beam qualities. Neither the presampling MTF nor the DQE showed any general strong beam quality dependence, whereas the NPS and NEQ did when compared at specific entrance air kerma values. The exposure dependency for the DQE was found to be considerable, with the detectors showing low DQE at low exposures, and higher DQE at higher exposures. It was found that the second generation has been substantially improved compared to its predecessor regarding all the relevant parameters. The DQE(0) at an entrance air kerma of 5 microGy increased from 9% to 15%, mainly due to a better system gain (including optical coupling efficiency and matching of the energy of the emitted light photons to the sensitivity of the CCD camera). The first generation of detectors was found to have problems with bad peripheral resolution [MTF(muN/2) <0.1]. This problem was nonexistent for the second generation for which uniform resolution has been obtained [MTF(muN/2)=0.3]. A theoretical calculation of the DQE of two model systems similar to the ones evaluated was also performed, and the results were comparable to the experimentally determined data at high exposures. The model shows that both systems suffer from low optical coupling efficiency due to the large demagnification used. The main conclusion is that although the second generation has been improved, there is still a problem with low system gain leading to relatively modest DQE values, especially at low exposures.
تواريخ الأحداث: Date Created: 20021101 Date Completed: 20030421 Latest Revision: 20170214
رمز التحديث: 20231215
DOI: 10.1118/1.1507781
PMID: 12408303
قاعدة البيانات: MEDLINE
الوصف
تدمد:0094-2405
DOI:10.1118/1.1507781