EOS® Micro-Dose Protocol: First Full-Spine Radiation Dose Measurements in Anthropomorphic Phantoms and Comparisons with EOS Standard-Dose and Conventional Digital Radiology (CR).

STUDY DESIGN: A comparative study of radiation dose measured in anthropomorphic phantoms.

OBJECTIVES: First, to report the first organ dose and effective dose measurements in anthropomorphic phantoms using the new EOS imaging micro-dose protocol in full-spine examinations. Next, to compare these measurements of radiation dose to measurements in the EOS standard-dose protocol and CR.

SUMMARY OF BACKGROUND DATA: Few studies evaluating organ dose and effective dose for the EOS low-dose scanner exists, and mainly for the standard-dose protocol. To the best of our knowledge, no studies of effective dose based on anthropomorphic phantom measurements exits for the new micro-dose protocol.

METHODS: Two anthropomorphic phantoms, representing a 5-year-old (pediatric) and a 15-year-old (adolescent). The phantoms were exposed to EOS micro-dose and standard-dose protocols during full-spine imaging. Additionally, CR in scoliosis settings was performed. For all modalities, organ doses were measured and effective doses were calculated using thermoluminescent dosimeters (TLD).

RESULTS: We found a 17-fold reduction (94%) of effective dose in micro-dose protocol compared with our CR system in the adolescent phantom. Micro-dose versus standard-dose protocol, showed a 6-fold reduction (83%), and for standard-dose versus our CR system a 2.8-fold reduction (64%) reduction of effective dose was observed.For the pediatric phantom, a 5-fold reduction (81%) of effective dose in micro-dose protocol compared to our CR system was observed. Micro-dose versus standard-dose protocol, showed a 7-fold (86%) reduction. However, we observed an increase in absorbed dose of 38% when comparing the EOS standard-dose protocol with our CR system.

CONCLUSIONS: The EOS imaging micro-dose option exposes patients to lower radiation doses than any currently available modality for full-spine examination. Expected reduction of dose was established for the adolescent phantom when comparing CR and standard-dose protocol. However, no reduction of effective dose with EOS standard-dose protocol compared to our reference CR system was observed in the pediatric phantom.

LEVEL OF EVIDENCE: N/A.