Lungs, CT scan. Coloured 3-D computed tomography (CT) scan of lungs in frontal view. The trachea (top centre) divides into two bronchi which transport air to and from the left and right lungs. The scan also shows how the bronchi divide into smaller bronchi and bronchioles. This image was produced using a multi-slice CT scanner, which uses a thin X-ray beam create 'slices' of the patient's body. A computer reconstructs the slices into coloured 3-D images. This image was created using OsiriX medical imaging software which allows users to navigate through animated fly-throughs of the data.