The three views
The scout view
The first view generated during the scanning process is the 'scout' view, or scanogram. This is similar in appearance to a plain x-ray.
The scout length is dependant on the scanner but can be up to 150cm long. This enables an image typically extending from the top of the head to the proximal femur (patient depending). In some instances the entire body bag will need to be imaged and this will necessitate the bag being rotated to scan from the bottom up, ensuring there is overlap of the imaging. The scouts can be obtained in approximately eight seconds, but this depends on the scanner.
Scout views are taken in both anterior-posterior and lateral views. These images are used to provide an overview of the patient to check for initial pathology and foreign objects and are essential to plan the next part of the scanning process; the axial slices.
The axial view
Once the scout image has been produced, the area of interest is selected and axial scans are undertaken. Modern 64-detector scanners allow the body to be scanned from the top of the head to the mid upper leg level (patient dependent) at 0.5mm intervals in one scan.
This however generates a large data set of approximately 5,000 DICOM images which equates to approximately 5GB of data. These images are then assessed for findings related to forensic pathology practice using MPR views.
3D Imaging
Once the axial scan data has been acquired, modern scanner software or commercially available software allows for the scan images to be reconstructed into 3D images.
The software allows the operator to view these images in a variety of 'windows': bone, soft tissue, lungs, vascular (requires contrast medium) etc. The generated images allow virtual dissection of the body from the outer surface inwards looking at the various component parts of the body. This process is however limited by the images generated and the software used.
The images can be rotated in the x, y and z planes. These images are then assessed for findings related to forensic pathology practice.
