Despite neonatal radiosensitivity, accurate lens dose assessments in computed tomography (CT) are lacking. We assessed the neonatal head CT eye lens dose under various scanning conditions, including vertical table displacement and organ-based exposure modulation (OEM), using the GAFCHROMIC LD-V1 (LD-V1), which can measure two-dimensional dose distributions, and we evaluated the limitations of conventional dose indices. The lens dose decreased with increasing distance from the isocentre for the Canon 320. Whereas, for the Canon 80 and Siemens, the dose peaked at +25 mm and then decreased. For the OEM, the dose reduction effect decreased at 30°. The CT dose index volume remained consistent. Spatially resolved dosimetry using the LD-V1 reveals beam overlap and positioning-related dose anomalies that cannot be captured by point dosimeters or conventional indices. The LD-V1 can effectively evaluate superficial dose distributions and guide dose optimization in neonatal imaging.
Gotanda et al. (Fri,) studied this question.