In the first webinar, participants were introduced to x-ray computed tomography (CT) and some key differences between CT and traditional x-ray. The basic specifications of a CT scanner (such as bore diameter, maximum image size, and table specifications) were introduced, with reference to their impact on whole body post-mortem scanning in particular. Basic considerations for deploying a CT scanner in a medical examiner setting (cost, personnel, space, safety) was also be discussed.
Participants were introduced to the workflow and imaging protocols used routinely at the New Mexico Office of the Medical Investigator (OMI), including the layout of the image rooms, body movement and positioning, and how the images are reconstructed and displayed. Image data is reconstructed into several series, each of which is a stack of 2-dimensional images (slices). Each series is reconstructed using a specific combination of algorithm, slice thickness, image plane (axial, coronal or sagittal), and default display settings (window and level), chosen to optimize the assessment of the anatomy of interest. The gray scale values displayed in CT are the Hounsfield Unit (HU) scale, a quantitative measure of the density of each tissue type.
Finally, image storage considerations were discussed. Participants were introduced to how a PACS (picture archiving and communications system) server enables large image data sets generated from PMCT to be accessed and reviewed at workstations throughout the office, while also ensuring that images are archived securely and redundantly.
1) Participants will be familiar with the basic technical and practical considerations involved with using x-ray computed tomography (CT) in a medical examiner or coroner setting.
2) Participants will have a basic understanding of how PMCT image data is acquired, reconstructed, and displayed to optimize the assessment of different anatomic structures.
3) Participants will appreciate the importance of systems for securely accessing, viewing, and archiving PMCT image data.
Funding for this Forensic Technology Center of Excellence event has been provided by the National Institute of Justice.
Natalie Adolphi, PhD, Director of the Center for Forensic Imaging