Evaluation of radiation dose and image quality following changes to tube potential (kVp) in conventional paediatric chest radiography

An evaluation of the effect of tube potential on clinical image quality using direct digital detectors for pelvis and lumbar spine radiographs

“…Overall, for both projections studied, results saw decreased DAP values and therefore decreased patient radiation doses, when the higher kVp values were used. This agrees with and validates the high kVp technique as a dose saving tool on direct digital radiographic systems 8,9,11‐17 . There were, however, differences in the amount of dose reduction observed between each projection and region of interest.…”

“…Each image was awarded a score from 0 to 15, based on a visual grading analysis (VGA) rubric, shown in Figure 2, that was derived from the Commission of European Communities Guidelines for Image Quality Criteria for Diagnostic Radiographic Images 26 . These guidelines have been widely used and adapted for image quality assessments in the literature, with a number of the previously mentioned high‐kVp studies adopting these guidelines in some capacity 8,11,12,14‐16 …”

“…The ‘15%’ and ‘10‐kVp’ rules are used to govern these techniques, stating that an increase in tube potential, measured as kilovoltage peak (kVp), by 15% or 10‐kVp requires the milliamperage seconds (mAs) value (which indicates the product of the tube current and exposure time) to be halved in order to keep the detector dose constant 2‐4,8‐10 . There are a large number of studies in the literature that confirm high kVp, low mAs techniques are effective in reducing patient radiation doses with digital imaging systems 8,9 , 11‐17 . These dose saving abilities, however, are not infinite; some studies show that as the kVp reaches higher values (i.e.…”

“…Traditionally, when film‐screen systems were used, an increase in kVp meant a loss of image contrast and overall image quality 1,4,5,7,8,16 . Currently, there is disagreement within the literature about how kVp selection effects image quality and contrast on digital imaging systems.…”

“…As previously described, with modern direct digital imaging systems, radiographers are no longer limited by the need to achieve a fixed optical density and therefore are able to increase the detector dose for improved signal to noise ratios, whilst keeping patient radiation doses the same, by reducing kVp values. 3,4,8 With these differing dose/image quality optimisation techniques and conflicting information seen in current published literature, questions are raised about the validity of such techniques and the best methods for optimisation. As clinical radiographers attempt to balance the trade‐off between radiographic image quality and patient radiation doses, further investigation into these optimisation techniques is required to determine which technique is most beneficial in which specific clinical situation.…”