RAD 254 Digital Imaging Basic Elements of Digital Imaging CR/DR

CD/DR Image data CAPTURE Image data PROCESSING Image DISPLAY Image data ARCHIVING Image data DISTRIBUTION & TRANSMISSION

Electronic Imaging Produce image –Digitize (A-D Converter) Process Data –OutputorD-A Conversion then Analog Display »Network »Archive Image

Image Acquisition & Detection Image detector types: –COMPUTED RADIOGRAPHY (CR) Photostimulable Phosphor (PSP) –DIRECT RADIOGRAPHY (DDR, “DR”) Solid State X-ray Detector (SSXD)

CR/DR Differences (steps) COMPUTED RADIOGRAPHY(CR) –X-ray – PSP – A-D Conversion – Data DIRECT RADIOGRAPHY (DDR, “DR”) –X-ray – SSXD - Data

Image Data Processing The selection of processing algorithms, and anatomic regions and radiographic projections controls how the acquired (latent) image is presented for display

Image Display In both CR and DR, a separate device MUST be used to display (as well as view) the digitized image (video monitor) –High resolution ( k matrix) –Diagnostic –Clinical Review –Web based

Image Data Archiving Storage and retrieval RAID –Storage – Terabyte (Tb) capacity Digital Linear Tape (DLT) Application Software Provider (ASP)

Image Data Distribution/Transmission One of the greatest strengths of a digital imaging system is the ability to share images simultaneously with multiple sites, sometimes over great distances (Iraq) –PACS –Teleradiology

Myth “DR” will turn a bad tech into a good tech! TRUTH – Digital radiography makes people “stupid” = give them an “auto pilot” mentality

Myth “Positioning and collimation don’t matter” Truth: Positioning and collimation are MORE critical with digital imaging systems

Myth “X-ray techniques don’t matter – you can use whatever you want.” Truth: Images almost always look better at higher exposures – very possible to over-expose the patient!

Caveat: Typically use HIGHER kVp –Get the photons to the image receptor –Algorithm to determine image quality STILL GREAT POTENTIAL TO OVER IRRADIATE THE PATIENT

Myth “DR only operates as a 200 speed system.” TRUTH: Can operate at whatever speed system you desire… but remember –NOISE vs. X-RAY DOSE

Myth “You can’t use grids with a CR system.” TRUTH: Grid use is still an important part of obtaining good image quality and controlling scatter

Computer Technophobia Nagy, P “A Symantic study found that 70% of users experienced difficulties with computers. Symptoms included swearing at computers, loss of productivity, and emotional distress. 21% of users suffer from ‘PC RAGE,’ sometimes involving physical assault on and damage of a computer.”

Skill sets NOT to forget: Basic Radiography 101 –Proper patient positioning –Proper beam restriction –Proper exposure factors –Correct patient ID –Correct R and L marker use

Skill sets NOT to forget: Basic x-ray physics –How a radiographic image is made –GOOD image quality elements –Effects of incorrect x-ray exposure selection and image quality

New Skill Set Development: Critical thinking skills Ability to identify a good image Knowledge of how to fix a repairable bad image Understanding the exposure indicator

New Terminology PACS –Picture Archival and Communications Systems PPACS –Picture and Paper and Communications System

New Terminology Teleradiology ASP –Application Service Providers DICOM –Digital Images and COmmunication in Medicine HL-7 –Health Level - 7

New Terminology HIS –Hospital Information System RIS –Radiology Information System HIS/RIS Broker (make sure they talk to each other)

Electronic Medical Record (EMR) DICOM Standard »Work Stations » HL-7 Standard

21 st Century Imaging All modalities will be in digital format Direct to Digital acquisition (SSXD) On-line access to patient records “Total” patient record (EMR) Software and equipment changes Radiation exposure a MAJOR concern Remote reading stations miles away

STOP the BS and just tell me! In CR – the photostimulable phosphor (just like an intensifying screen) is exposed to x-rays. The PSP cassette is then “scanned” by a laser “reader” to obtain the image (stored images are released as varied shades of “light”) DR/DD uses a “flat panel detector(s) and a scintillator combined with a photodiode the light produced is “digitized” and translated into “densities” for computer viewing.

Thanks to: Rolando R. Reyes, B.S., R.T.(R) –Senior Project Manager –Eastman Kodak Health Imaging –Rochester, NY