Paediatric pelvic imaging: optimisation of dose and technique using digital grid-controlled pulsed fluoroscopy

Background. An audit Of paediatric pelvic radiographs identified deficienci es ill gonad shield placement and radiographic technique. Objective. A technique using grid-controlled fluoroscopy (GCF), with hard c opy images in frame grab and digital spot image (DSI) format was evaluated to optimise gonad shield placement and reduce the dose given to children wi th Perthes disease and Developmental Hip Dysplasia (DDH) attending for pelv ic radiography. Materials and methods. Phantom and patient dose surveys of conventional and fluoroscopic techniques were carried out. Image quality and radiation dose were compared for the frame grab and E)SI techniques. Retrospective evalua tion was undertaken to compare their clinical acceptability Results. Both fluoroscopic techniques gave considerably less radiation than conventional non-grid radiography (67-83 %, P < 0.05). The frame grab tech nique gave less radiation than DSI (P < 0.05). There was no significant dif ference in the clinical acceptability scores of the DSI and frame grab imag es. Conclusion. Fluoroscopy acquired images are now used since the fluoroscopic techniques give much less dose than conventional radiography and provide i mages of sufficient quality for clinical assessment. Indeed, as there was n o significant difference in clinical usefulness between the frame grab and DSI techniques, it is planned to use frame grab alone, thus gaining additio nal dose saving.