2020 年 76 巻 5 号 p. 463-473
Purpose: To compare the visibility of anatomic structure in chest radiography acquired with different beam quality (120 kV beam and 90 kV beam with 0.15 mmCu) using CsI-flat panel detector. Method: Pair image obtained by different beam quality of 100 person's chest radiographies which were taken periodical health examination were compared with the visibility of normal structures (pulmonary vessels) and abnormal opacities by two pulmonologists and four radiological technologists. Moreover, the spectrum of the two beam quality were calculated using Monte Carlo simulation. Result: Dominant observers gave high score significantly (p<0.01) to the 90 kV beam's image in spite of 20% less dose. Monte Carlo simulation showed that 90 kV beam with 0.15 mmCu were much absorbed primary photon than 120 kV beam to CsI detector, and less absorbed secondary photon. Conclusion: The visibility of anatomic structure and abnormal opacities in FPD chest radiography was improved by using the 90 kV beam with 0.15 mmCu than traditional 120 kV beam's chest radiography.
