Low-dose Chest 16-slice CT: A Clinical Study

一, Objective: Evaluating the effect on normal structures and image quality of low-dose chest 16 slice CT; studying the application value of low-dose chest MSCT in clinical work.Materials and methods: Low-dose chest MSCT was performed in 150 patients of 2004.3-2005.4 in which 150 health examination cases, All patients were scanned on a TOSHIBA Aquilion 16 CT scanner. For comparing study, all whole lung scanning adopted 1.0 mm collimation, p=0.938 and 120 Kv. 0.5s/Rot, FOV 280～330mm. 7.0 mm lung window and 10mm mediastinum window images were reconstructed indivisually. All conditions were identical except the tube current in two dosage scanning. 10 mAs was used in all low-dose scanning. 5mAs or 20mAs or 30mAs was used in the apex of the lung according to the image quality. Three levels of the apex of the lung, aortic arch, and tracheal carina were selected, the difference of two dose MSCT in imaging quality of lung and mediastinum window to displaying normal structures were compared.Result: 20 mAs was enough in all the cases to displaying the normal structures and lesions. There is light decrease in 10mAs and apparent in 5mAs but the operation is not affected apparently in the lung window. The noise was apparent in 5mAs of the mediastinum window. There was...