CAN PATIENT POSITIONING USING AN ULTRASHORT FLUOROSCOPIC PULSEBE JUSTIFIED?

摘要

A study was performed to find out if a new fluorography procedure, a so-called pre-shot technique, could bernjustified as a tool for patient positioning to reduce patient dose and/or the amount of retakes with conventional X-rayrnexaminations. The ratio of fluorography (S) and radiography (G) for two tissue types was obtained from dosernmeasurements (PMX-III; RTI Electronics) by performing a simulation on a RANDO skull (0.69% S/G) and anrnabdomen (2.49% S/G) phantom. During 8 weeks, the radiographic technique (type of examination, incidence,rnnumber of necessary pre-shots and the number of radiographs per imaging session) was recorded fromrnmusculoskeletal examinations performed on a modified X-ray system (Siemens, Seregraph CF fluorospot).rnAnalyses of the data shows that in up to 40% of the cases more than one shot has been used. This increases thernrelative amount of patient entrance dose up to respectively 1.31% (skull) and 3.0% (abdomen). Taking intornaccount the retake rates with blind positioning (from literature: 3,2%-10%) and high patient dose withrnfluoroscopically guided positioning, we may justify the use of this alternative technique for X-ray departmentsrnwith high retake rates and/or fluoroscopically guided positioning. The use of the proposed technique will reducernthe retake rate to a minimum or zero and/or the overall patient dose. Several advantages are gained whenrncombining this technique with storage phosphor plates: increase of patient throughput, decrease or removal of thernclear room functionality.