Digital Radiography DR (sometimes referred to as Direct Radiography)
These systems perform image capture and image processing without the need to handle cassettes. They rapidly display images within 4-10 seconds and are divided into two groups:
Flat Panel FP
These systems use a relatively thin plate (usually 2” or less) to convert x-rays by the use of an imaging sensor (amorphous silicon array) and a conversion screen into a digital image.
Charge Coupled Device CCD
These systems use a high mega pixel “camera” (6, 9 or 16 MP) to capture the image directly from an illuminating plate (syntillation material: either Cesium Iodide or Gadox). CCD technology is widely used in astronomy (the Hubble), and bio-medical (ridged and flexible scopes, electron microscopes). Consumer products such as Digital Camcorders, Digital Cameras and in “Human” X-ray systems.
Computed Radiography CR
These systems are considered indirect systems that convert x-rays to stored light as an intermediate step. CR systems use a cassette with a phosphor plate to store the image and a reader/scanner to convert the stored illuminated image into a digital image. CR systems function like a conventional wet system with cassette handling and processing steps.
A fourth option or “technology” is using a “Digital Converter” for your current x-ray films. This is similar to using a digital camera, tripod and a view box for converting your existing film images into digital images. This process is used to electronically send your film images out for consultation or being able to archive your film images once you have purchased a Digital X-ray system.
You should be aware of the file format used by the lower end CCD and Digital Converter systems (including your digital camera) many use ONLY a JPEG format. All of the “high end” systems use a DICOM file format. Images stored or used as JPEG, TIF & BMT file format can be electronically transmitted (email) quickly, as they are much smaller file sizes than DICOM files. However, images saved as JPEG, TIF, BMT can also be easily altered using Photoshop or any commercially available graphics program.
In addition to talking about file formats… there are some important terminology “buzz words” you should be aware of and able to use when talking the “Digital Talk”.
DICOM: Digital Imaging and Communications in Medicine (DICOM)
Provides standardized formats for images, a common information model, application service definitions, and protocols for communication. It is the “Human” standard for medical image format regardless of the origin (radiology, dermatology, pathology, endoscopy etc.). A DICOM file format is very difficult to alter and the file contains a set of standard “tags” which is a list of information that other DIOCM compatible systems can use to identify the file (what product created it, facility demographic information, patient information, etc.)
PACS: Picture Archiving and Communication System (PACS)
Is a software program that allows displaying of digital images from multiple sources (X-ray, Ultrasound, MRI, CT, etc.) on a single computer screen.
RIS: Radiology Information System (RIS)
An information program/system developed for use within the Radiology Department.
HIS: Hospital Information System (HIS)
An information program/system developed for use Hospital wide. Allowing information from all departments to be shared and integrated. i.e. Veterinary Practice Management Software