Room: Room 205
Purpose: To investigate if a synthetic localizer radiograph (SLR) created from the 3D-volume of an ultra-low dose spiral (ULDS) scan can be used for CT scan planning and replace a traditionally acquired localizer radiograph (LR).
Methods: Patient doses were compared using MC dose estimations. The water equivalent diameter (WED) of an automatic tube current modulation phantom (centered and mis-centered) was estimated and compared using ULDSs and LRs. The ability to use an SLR relative to an LR was rated for 10 patients (with informed consent) undergoing CT scans of thorax-abdomen by 4 experienced Radiologists and 2 experienced Radiographers.
Results: Patient doses from an ULDS and LRs (vendorâ€™s recommended technique parameters) can be kept at an equal level. WEDs estimated from ULDS are not sensitive to mis-centering compared to WEDs estimated from LRs. CT scan planning based on SLRs can be equally good as based on LRs.
Conclusion: Using ultra-low dose CT spiral scans can replace localizer radiographs for CT scan planning, while providing advantages from the underlying ultra-low dose spiral scan.
Funding Support, Disclosures, and Conflict of Interest: Patrik Nowik is a consultant lecturer for Siemens Healthcare Sweden.