Reducing Dose for Digital Cranial Radiography: The Increased Source to the Image-receptor Distance Approach

Abstract

This investigation proposes that an increased source to the imagereceptor distance (SID) technique can be used to optimize occipital frontal and lateral cranial radiographs acquired with direct digital radiography. Although cranial radiography is not performed on a routine basis, it should nonetheless be optimized to keep the dose to the patient as low as reasonably achievable, particularly because it can form part of the facial bone and sinus series. Dose measurements were acquired at various SIDs, and image quality was assessed using visual grading analysis. Statistically significant reductions in the effective dose between 19.2% and 23.9% were obtained when the SID was increased from the standard 100 to 150 cm (P .05), and visual grading analysis scores indicate that image quality remained diagnostically acceptable for both projections. This investigation concludes that increasing the SID effectively optimizes occipital frontal and lateral skull radiographs. Radiology departments must be advised of the benefits of this technique with the goal of introducing an updated reference SID of 150 cm into clinical practice.R ESUM E Cette etude pose comme hypoth ese que la technique de l'augmentation de la distance entre la source et le r ecepteur d'image (SID) peut etre utilis ee pour optimiser les radiographies occipitales frontales (OF10 ) et crâniales lat erales acquises par radiographie num erique directe. Bien que la radiographie crâniale ne se pratique pas couramment, elle doit quand mêmeêtre optimis ee pour garder la dose pour le patient la plus basse qui soir raisonnablement possible d'atteindre, notamment parce qu'elle peut s'inscrire dans une s erie de la structure osseuse faciale et des sinus. Des mesures de dose ont et e prises a diff erentes SID et la qualit e de l'image a et e evalu ee au moyen de l'analyse de classement visuel (VGA). Des r eductions statistiquement significatives de la dose variant entre 19,2 % et 23,9 % ont et e obtenues lorsque la SID a et e port ee de la distance standard de 100 cm a 150 cm (p 0,05) et les notes VGA indiquent que la qualit e diagnostique de l'image reste acceptable pour les deux projections. Cette etude conclut que l'augmentation de la SID permet effectivement d'optimiser les radiographies occipitales frontales et crâniales lat erales. Les services de radiographie doiventêtre inform es des avantages de cette technique dans le but d'adopter une mise a jour a 150 cm de la SID de r ef erence dans la pratique clinique.

A Survey of Structural Design of Diagnostic X-ray Imaging Facilities and Compliance to Shielding Design Goals in a Limited Resource Setting

“…These findings call for standardization in radiology room designs and regular radiation safety assessment as recommended by regulatory bodies (4,5). Time, distance and shielding are well-established dose reduction strategies in radiography (12). Measurement of distances in diagnostic radiography is of great significance, as the intensity of radiation decreases as the square of its distance from the source, according to the inverse square law (12).…”

“…Time, distance and shielding are well-established dose reduction strategies in radiography (12). Measurement of distances in diagnostic radiography is of great significance, as the intensity of radiation decreases as the square of its distance from the source, according to the inverse square law (12). Apart from decreasing the intensity of radiation, maximized distance also helps to minimize the cost of shielding (9), and also has clinical significance as it aids in proper patient positioning and geometric display of anatomy of interest and pathology on radiographs (11,12).…”

“…Measurement of distances in diagnostic radiography is of great significance, as the intensity of radiation decreases as the square of its distance from the source, according to the inverse square law (12). Apart from decreasing the intensity of radiation, maximized distance also helps to minimize the cost of shielding (9), and also has clinical significance as it aids in proper patient positioning and geometric display of anatomy of interest and pathology on radiographs (11,12). If the x-ray room size is not adequate and the location of the x-ray tube to the nearest wall or chest stand is not optimized, these could lead to poor positioning and wrong diagnosis of numerous chest pathologies.…”

“…Time, distance and barrier are cardinal principles of radiation protection in projection radiography. Apart from the radiation protection benefit of longer distances in projection radiography, it also improves image sharpness through geometric means both in film screen and digital radiography (11,12).…”

Examining Practitioners' Assessments of Perceived Aesthetic and Diagnostic Quality of High kVp–Low mAs Pelvis, Chest, Skull, and Hand Phantom Radiographs

“…Furthermore, despite the Canadian Association of Medical Radiation Technologists' clearly outlined ALARA mandate and the wealth of evidence regarding dose optimization strategies, there is evidence that these strategies, including the high kVp-low mAs strategy, are not being fully realized within radiology departments [13]. Is it that practitioners do not find high kVp-low mAs images to be aesthetically pleasing?…”