An investigation of the effects of anti-scatter grid usage on patient dose and vessel visibility in pediatric voiding cystourethrography as a function of patient size

Abstract

Anti-scatter grids represent an important way of improving image quality in x-ray based exams. However, their use comes with increased radiation dosages. Removing anti-scatter grids represents a potential way to limit radiation dosage. Voiding cystelourethrograms (VCUG) are commonly done fluoroscopic procedures done in pediatric populations. To limit radiation dosage from VCUGs we undertook a study to determine how image quality changes with the removal of anti-scatter grid during VCUGs. A water based phantom with simulated ureters was constructed and imaged with the grid in place and removed. The depth of the water in the phantom was increased over the course of the experiment to simulate increasing pediatric patient thickness. Four readers, two radiologists and two imaging physicists, assessed the visibility of the ureters and scored the images on a Likert scale. The results indicated that there is no significant difference in image quality between images acquired with the anti-scatter grid in place versus when it is removed. This means that anti-scatter grid removal is a viable strategy for dose saving in pediatric populations undergoing voiding cystelourethrograms.