SA Journal of Radiology - Volume 13, Issue 4, 2009
Volume 13, Issue 4, 2009
A pilot study evaluating erect chest imaging in children, using the Lodox Statscan digital X-ray machine : original articleSource: SA Journal of Radiology 13, pp 80 –85 (2009)More Less
Background. Chest radiography accounts for a significant proportion of ionising radiation in children. The radiation dose of radiographs performed on the Lodox Statscan system has been shown to be lower than that of a computed radiography (CR) system. The role of the Lodox Statscan (subsequently referred to as the Statscan) in routine erect chest radiography in children has not been evaluated.
Objective. To evaluate the image quality and diagnostic accuracy of erect paediatric chest radiographs obtained with the Statscan and to compare these with conventional erect chest images obtained with a CR system.
Materials and methods. Thirty-three children with suspected chest pathology were enrolled randomly over a period of 3 months. Erect chest radiographs were obtained with the Statscan and a Shimadzu R-20J X-ray machine coupled with a Fuji FCR 5000 CR system. Image quality and diagnostic accuracy and diagnostic capability of the two modalities were evaluated and compared.
Results. The erect Statscan allowed superior visualisation of the 3 major airways. Statscan images, however, demonstrated exposure and movement artifacts, with hemidiaphragms and ribs most prone to movement. Bronchovascular clarity was also considered unsatisfactory on Statscan images.
Conclusion. The Statscan has limitations in erect chest radiography in terms of movement artefacts, exposure fluctuations, and poor definition of lung markings. Despite this, the Statscan allows better visualisation of the major airways, equivalent to a 'high kV' film, at a fraction of the radiation dose, which supports the finding of an earlier study evaluating Statscan images in trauma cases, where the images were taken supine. The Statscan has great potential in assisting in the diagnosis of childhood childhood tuberculosis where airway narrowing occurs as a result of nodal compression.
The relationship between compression force, image quality and radiation dose in mammography : original articleSource: SA Journal of Radiology 13, pp 86 –92 (2009)More Less
Background. Mammography aims to obtain mammograms of the best possible image quality with the least possible radiation dose. Theoretically, an increase in breast compression gives a reduction in thickness without changing the density, resulting in improved image quality and reduced radiation dose.
Aim. This study investigates the relationship between compression force, phantom thickness, image quality and radiation dose. The existence of a compression point beyond which increased compression gives a change in density rather than thickness is also considered.
Method. Image quality is assessed with a contrast-detail phantom within Superflab phantom on a computed radiography (CR) mammography unit using automatic exposure control (AEC). Image quality is determined by visual inspection and image quality figure (IQF) scoring. The effect of compression and lesion depth on image quality is determined. Entrance and exit doses are calculated. The relationship between entrance dose, compression and thickness is investigated, as is the existence of a compression point beyond which a change in phantom density occurs. The average glandular dose (AGD) is calculated from the scanning average level (SAL) and logarithmic mean (LgM) and compared with the allowable limit.
Results. The geometry effect was not observed. An improvement in image quality with increased compression was found. Entrance dose decreased with increased compression. This trend was not observed with exit dose as AEC was used and exit dose was calculated from SAL values. The 'change-in-density' point of compression was determined. Both LgM and SAL could be used successfully for AGD calculation.
Source: SA Journal of Radiology 13, pp 94 –96 (2009)More Less
Source: SA Journal of Radiology 13, pp 98 –101 (2009)More Less
A 17-year-old girl presented with abdominal pain due to contained rupture of a left common iliac artery aneurysm. This was accompanied by abdominal aortic and superior mesenteric artery aneurysms. Despite emergency vascular surgery, the patient died a week later. Post-mortem examination revealed intimomedial mucoid degeneration. This rare condition has been described in predominantly South African black patients, especially females, and occurs at a younger age than degenerative aortic aneurysms.
Report on the RSSA Neuroradiology and Body Imaging Advances Congress, Sandton, 28 - 30 August 2009 : radio active newsAuthor Aisne StokerSource: SA Journal of Radiology 13, pp 106 –107 (2009)More Less
The RSSA Neuroradiology and Body Imaging Advances Congress 2009 was a joint meeting between the RSSA, the RSNA, and the International Society for Magnetic Resonance in Medicine Global Outreach Programme (ISMRM). The RSSA also secured the participation of three RSNA international visiting professors (IVPs).