liu.seSearch for publications in DiVA
Change search
ReferencesLink to record
Permanent link

Direct link
Evaluation of image quality in fluoroscopy by measurements and Monte Carlo calculations
Finnish Centre for Radiat. & Nucl. Safety.
Linköping University, Department of Medicine and Health Sciences, Radiation Physics . Linköping University, Center for Medical Image Science and Visualization, CMIV. Östergötlands Läns Landsting, Centre of Surgery and Oncology, Department of Radiation Physics. Linköping University, Faculty of Health Sciences.ORCID iD: 0000-0003-3352-8330
1995 (English)In: Physics in Medicine and Biology, ISSN 0031-9155, Vol. 40, no 4, 589-607 p.Article in journal (Refereed) Published
Abstract [en]

The authors have studied image quality in fluoroscopy, as related to the detectability of low-contrast iodine or acrylic (PMMA) details added to a homogeneous 20 cm thick PMMA phantom, by experimental measurements of the signal-to-noise ratio (SNR) and by Monte Carlo calculation. The agreement between the measured and calculated SNR at equal absorbed dose in the phantom showed that the imaging performance of X-ray image intensifier (XRII) based fluoroscopic systems is well understood and can be mainly accounted for by X-ray attenuation in the phantom and the detail, and by the interaction statistics of primary and secondary (scattered) X-ray quanta in the input phosphor of the XRII. The electronic noise sources in the video chain bad only a small effect on the detectability of the details studied here. The optimal X-ray tube potential was 50-60 kV for detecting the low-contrast iodine detail in the phantom, and 70-100 kV for detecting the thin PMMA detail. For the task of detecting the iodine detail the use of a fibre-interspaced antiscatter grid improved the dose-to-information conversion efficiency of the imaging system by a factor of 2.2 as compared to imaging without the grid, and additional filtering of the X-ray beam by 0.25 mm Cu increased the efficiency by a factor of 1.6. Monte Carlo results were further used to estimate the potential of increasing the dose-to-information conversion efficiency by imaging system design changes. For the detection task of a static, low-contrast, low-spatial-frequency iodine contrast material detail embedded in a 20 cm thick soft-tissue phantom, the greatest contributions for further improvement could be achieved by improved antiscatter devices, X-ray spectrum modification, and by decreasing the absorption in the material layers in front of the CsI phosphor of the XRII. Contrary to this, no significant efficiency increase could be obtained by increasing the CsI phosphor coating thickness from the present value of 180 mg cm-2, or by changes in the video chain characteristics. The maximum potential of efficiency improvement is a factor of 6.3 when compared to the reference fluoroscopy system operated at 60 kV with 2.7 mm Al primary beam filtration, and a factor of 3.9 when compared to the reference system at 50 kV with the primary beam filtration added by 0.25 mm Cu.

Place, publisher, year, edition, pages
1995. Vol. 40, no 4, 589-607 p.
National Category
Medical and Health Sciences
URN: urn:nbn:se:liu:diva-20937DOI: 10.1088/0031-9155/40/4/007OAI: diva2:236838
Available from: 2009-09-25 Created: 2009-09-25 Last updated: 2013-09-03

Open Access in DiVA

No full text

Other links

Publisher's full text

Search in DiVA

By author/editor
Sandborg, Michael
By organisation
Radiation Physics Center for Medical Image Science and Visualization, CMIVDepartment of Radiation PhysicsFaculty of Health Sciences
In the same journal
Physics in Medicine and Biology
Medical and Health Sciences

Search outside of DiVA

GoogleGoogle Scholar
The number of downloads is the sum of all downloads of full texts. It may include eg previous versions that are now no longer available

Altmetric score

Total: 29 hits
ReferencesLink to record
Permanent link

Direct link