Evaluation of the Patient Effective Dose in Whole Spine Scanography Based on the Automatic Image Pasting Method for Digital Radiography.
BACKGROUND
Whole spine scanography (WSS) is a radiologic examination that requires whole body X-ray exposure. Consequently, the amount of patient radiation exposure is higher than the radiation dose following routine X-ray examination.


OBJECTIVE
Several studies have evaluated the patient effective dose (ED) following single exposure film-screen WSS. The objective of this study was to evaluate patient ED during WSS, based on the automatic image pasting method for multiple exposure digital radiography (APMDR). Further, the calculated EDs were compared with the results of previous studies involving single exposure film-screen WSS.


METHODS
We evaluated the ED of 50 consecutive patients (M:F = 28:22) who underwent WSS using APMDR. The anterior-posterior (AP) and lateral (LAT) projection EDs were evaluated based on the Monte Carlo simulation.


RESULTS
Using APMDR, the mean number of exposures was 6.1 for AP and 6.5 for LAT projections. LAT projections required more exposures (6.55%) than AP projections. The mean ED was 0.6276 mSv (AP) and 0.6716 mSv (LAT). The mean ED for LAT projections was 0.6061 mSv in automatic exposure control (AEC) and 0.7694 mSv in manual mode. The relationship between dose-area-product (DAP) and ED revealed a proportional correlation (AP, R(2) = 0.943; LAT, R(2) = 0.773). Compared to prior research involving single exposure screen-film WSS, the patient ED following WSS using APMDR was lower on AP than on LAT projections.


CONCLUSIONS
Despite multiple exposures, ED control is more effective if WSS is performed using APMDR in the AEC mode.
Department of Radiologic Science, College of Health Science, Korea University, Seoul, South Korea.
Jung-Su
JS
Kim
Department of Diagnostic Radiology, CHA Bundang Medical Center, CHA University, Gyeonggi-do, South Korea.
Sang-Wook
SW
Yoon
Department of Radiologic Science, College of Health Science, Korea University, Seoul, South Korea.
Deok-Nam
DN
Seo
Department of Radiologic Science, College of Health Science, Korea University, Seoul, South Korea.
So-Ra
SR
Nam
Department of Radiologic Science, College of Health Science, Korea University, Seoul, South Korea.
Jung-Min
JM
Kim
Health Physics; Radiation Dosage; X-Rays