Joemon John PET Imaging Centre Guys, Kings & St.Thomas School of Medicine Kings College London
Evaluation of whole body dose reduction by modified injection technique. BACKGROUND MATERIALS & METHODS RESULTS CONCLUSION
PET Imaging at St Thomas Hospital Facilities two dedicated PET/CT scanners on-site cyclotron radiochemistry production laboratory Scanning activity clinical & research scanning – 3,500 patient scans per annum oncology, cardiology & neurology 5 dedicated PET/CT scanning technologists / radiographers
Radiation Protection Issues Increase in patient throughput with PET/CT scanning raised concerns about staff whole body radiation dose Imaging staff receive radiation when handling radioactivity & interaction with patients 65 % of staff WBD received when administering radiopharmaceutical activity to the patient Staff Dose in Sv injecting Total Dose in Sv % from injecting A % B % C % D % E %
Purpose of the study To improve the method of F- 18 FDG administration To evaluate a modified injection technique for reducing staff WBD To compare WBD received during the time of administration by comparing the two different techniques
Materials & Methods Personnel involved 5 technologists 120 ambulatory clinical patients Devices syringe holders lead shields dose monitor(Atomtex) extension tubing ( 30cm long, 1mm ID, 2mm OD )
Activity administration Old technique New technique
Old technique
New technique
Results Staff member Doses in Sv (old technique) Doses in Sv (new technique) Difference A % B % C % D % E %
Results staff Sv
Results Mean WBD received during administration: old technique was 0.64 – 1.9 Sv new technique was 0.39 – 0.94 Sv Other factor affecting WBD: speed of administration
Conclusion Simple technique Cost effective - less than £1 per patient increase Significant reduction in staff WBD Increased patient throughput per day whilst remaining within staff dose limits
Activity administration Old technique New technique
Whole body doses No of clincal scans done in 2006/ /
Other methods to reduce WBD
WBD Distribution