X-ray tube current modulation and patient doses in chest CT.

The aim of the study was to investigate how patient effective doses vary as a function of X-ray tube projection angle, as well as the patient long axis, and quantify how X-ray tube current modulation affects patient doses in chest CT examinations. Chest examinations were simulated for a gantry CT scanner geometry with projections acquired for a beam width of 4 cm. PCXMC 2.

Patient doses and projection angle in cone beam CT.

Purpose: To investigate how x-ray tube projection angle affects organ and effective doses to patients undergoing a CT examination on a cone beam scanner.

Methods: The authors investigated two cone beam CT systems that use a flat panel detector to capture the x-ray pattern transmitted through patients. One system had the flat panel detector and x-ray tube mounted on a conventional CT gantry (gantry CT), whereas the other CT scanner had the x-ray tube and flat panel detector mounted on a C-arm apparatus (C-arm CT).