DATA COMPRESSION FOR CHEST RADIOGRAPHY AND MAMMOGRAPHY USING COMPUTED RADIOGRAPHY
Seiichi Murakami, Nobuhiro Oda, Kunihiro Terata, Yukitaka Kawashita, Yukako Ueno, HIDEICHIROU NAKANO, Tomoko Mori, Hajime Nakata · Japanese Journal of Radiological Technology · 1995
We have evaluated the degradation of image quality by irreversible data compression in computed radiography (CR). Analysis of the receiver operating characteristics (ROC) curves were made from the images reconstructed with reversible data and two types of irreversible compression data. With acryl beads (2 mmφ) on the phantom simulating chest, the detectablity as regards the images with irreversible compression was lower than that with reversible data. With film disk (5 mmφ, 0.9 mm thickness), there was no difference between the detectability for both images. In clinical cases of chest radiography, ROC for pneumothorax, pulmonary nodules and reticulonodular opacities regards chest rediographs in newborns, infants and adults revealed no significant difference as regards the images, with reversible data irreversible compression. With film disk (10 mmφ, 0.1 mm thickness) regarding the phantom simulating brest, there was no images with a difference in detectability. With glass beads (0.2 mmφ), irreversible compression was inferior to that with reversible data. In clinical cases of mammography, images with irreversible compression were greatly inferior regarding the visibility of calcification smaller than 0.25 mm.