title: [Ultra-low-dose spiral (helical) CT of the thorax: a filtering technique].
abstract: To reduce the radiation dose from spiral (helical) CT, a custom-made aluminium filter was installed in the X-ray tube and a reduction of effective tube current was attempted. A pronounced reduction of effective tube current, namely, 6 and 3 mA, was achieved with 26 and 37 mm thick aluminium filters, respectively. Visualization of normal lung structure was accomplished with both 6 and 3 mA settings. However, images of 3 mA failed to delineate mediastinal structures because of marked beam hardening resulting from the bone structure of the thoracic inlet. Six mA was considered the lowest dose setting of spiral (helical) CT of the thorax that could be used for lung cancer screening.
authors.affiliation: Department of Radiology, Shiga University of Medical Science.
authors.forename: N
authors.initials: N
authors.lastname: Nitta
authors.forename: M
authors.initials: M
authors.lastname: Takahashi
authors.forename: K
authors.initials: K
authors.lastname: Murata
authors.forename: M
authors.initials: M
authors.lastname: Mori
authors.forename: K
authors.initials: K
authors.lastname: Shimoyama
authors.forename: A
authors.initials: A
authors.lastname: Mishina
authors.forename: H
authors.initials: H
authors.lastname: Matsuo
authors.forename: R
authors.initials: R
authors.lastname: Morita
authors.forename: K
authors.initials: K
authors.lastname: Sugii
authors.forename: A
authors.initials: A
authors.lastname: Nomura
mesh_terms: D000328:Adult; D000535:Aluminum; D006801:Humans; D008168:Lung / Q000000981:diagnostic imaging*; D008175:Lung Neoplasms / Q000000981:diagnostic imaging; D008297:Male; D019047:Phantoms, Imaging; D011829:Radiation Dosage; D011835:Radiation Protection / Q000379:methods*; D014057:Tomography, X-Ray Computed / Q000379:methods*
chemical_list: D000535:Aluminum