Cr & dr

50 %
50 %
Information about Cr & dr
Education

Published on March 20, 2014

Author: muhammadbinzulfiqar5

Source: slideshare.net

Description

Comparative Study of CR and DR

Dr. Muhammad bin zulfiqar PGR-1 SIMS/ SHL.

Basics of Digital Language

5 Byte The basic unit of binary coded information Kilobyte—210 – 1024 bites Megabyte—1024 times1024bites

Performance parameters Pixel: Smallest complete sample of an image. Has a varied set of tones in shades of white/ black/grey. Expressed in binary codes (bits). Size of the pixel : Smaller the size , better resolution. CR- 50 to 200 microns, DR- 100 to 200 microns, DM- 50 to 100 microns. Gray Scale: Shades of Gray in between pure black and pure white. Bit Depth: No of shades to define each pixel ,measured as no of bits. Larger the depth, incr gray scale and large file size.

Spatial Resolution: finer details, diff objects in an image. Depends on sampling frequency and no of pixels. expressed in lp/mm. Contrast Resolution: Color or gray scale differentiation. Indicate the no of shades of grey that a detector can capture. File Size. Performance Parameters(contd..)

DIGITAL PROJECTION RADIOGRAPHY COMPUTED RADIOGRAPHY (CR) DIGITAL RADIOGRAPHY (DR)

11011101 CR X-RAYS CR PLATE SCANNER

DETECTORS 11011101 DR X-RAYS

Computed Radiography (CR) Been around since 1980-81 Uses same radiographic equipment No change in X-ray machine Uses an imaging plate Contains a photostimulator phosphor Need a cassette reader Images can be sent to a PACS

Computed Radiography (CR) Re-usable metal imaging plates replace film & cassette Uses conventional bucky & x-ray equipment                                                                  

CR SYSTEM COMPONENTS CASSETTES (phosphor plates) ID STATION IMAGE PREVIEW STATION DIGITIZER VIEWING STATION

CR PLATE

CASETTE CONSTRUCTION LIGHTWEIGHT ALUMINUM PLASTIC STEEL FRAME FRONT PANEL MADE OF LOW ATTENUATION CARBON FIBER

PROTECTIVE LAYER PHOSPHOR LAYER ANTI-HALO & REFLECTIVE LAYER BASE BACKING LAYER

PHOSPHOR LAYER BASE Ba FX: Eu +2 PET- POLYETHYLENE TERAPHTALATE PROTECTIVE LAYER FLUORINATED POLYMER MATERIAL PROTECTS PHOSPHOR LAYER

ANTI-HALO LAYER + REFLECTIVE LAYER PREVENTS LASER FROM PASSING THROUGH. REFLECTED LIGHT FROM PHOSPHOR IS ALLOWED TO PASS. BACKING LAYER PROTECTS THE BASE FROM DAMAGE.

SCATTER

REMOTE OPERATOR PANEL

CR Operation

Add module code number and lesson title 29

Add module code number and lesson title 30 The principle of PSP Excitation Storage Emission CB Trap ADC PMT

Higher Energy Electron State Lower Energy Electron State - - - - - - - - - - - - - - - - - - - - - - - - - - - X-Ray Photon - Photon pumps electron to higher energy state

Add module code number and lesson title 36 (Images courtesy of AFGA) PSP digitizer Casette and PSP Workstation

Reading Imaging Plate Reader scans plate with laser Laser releases electrons trapped in high energy states Electrons fall to low energy states Electrons give up energy as visible light Laser Beam Higher Energy Elect ron St at e Lower Energy Elect ron St at e - - - - - - - - - - - - - - - - - - - - - - - - - - - - Lower Energy Electron State

Reader scans plate with laser light using rotating mirror Film pulled through scanner by rollers Light given off by plate measured by PM tube & recorded by computer Reading Imaging Plate

Conventional CR Scanning

25% OF STORED ENERGY WITHIN 8 HOURS

CR PLATE CR SCANNER/READER CR AFTER EXPOSURE IS INSERTED INTO CR SCANNER

CR Exposure & Readout

PM TUBE AMPLIFIER ADC LASER LIGHT GATE

PLATE & F-CENTERS LASER 633 nm PHOTOSTIMULABLE LUMINESCENCE 390-400 nm

After read-out, plate erased using a bright light Plate can be erased virtually without limit Plate life defined not by erasure cycles but by physical wear

IMAGE DISPLAY Typical image plate can be reused thousands of times

CR Resolution Small cassettes have better spatial resolution Smaller pixels More pixels / mm

IMAGE CHECK-INDEX

IMAGE MANIPULATION-WINDOWING

PICTURE DESTINATION -PACS

CR CHARACTERISTIC CURVE VERY WIDE LATITUDE CR SYSTEMS LESS RADIOGRAPH REPEATS

Much greater latitude than screen/film Plate responds to many decades of input exposure under / overexposures unlikely Computer scale inputs exposure to viewable densities Unlike film, receptor separate from viewer

CHARACTERISTIC CURVE LATITTUDE OF CR LATITTUDE OF FILM

IMAGE CAN BE SALVAGED WITH CR 500% OVEREXPOSURE 80% UNDEREXPOSURE USE ADEQUATE KVP

HARD COPY GENERATED IN LASER PRINTER

CR SYSTEM EFFICIENCY CHARACTERISTIC QDE- QUANTUM DETECTION EFFICIENCY NO NEED FOR SCREENS QDE: THE MEASURE OF THE EFFICIENCY OF CR SYSTEM TO CONVERT REMNANT X-RAYS TO USEFUL IMAGE SIGNAL QDE PATIENT DOSE

Receptor provides direct digital output No processor / reader required Images available in < 15 seconds Much less work for technologist

69

72

PACS and DICOM  THE ROLE OF PACS : A Picture Archiving and Communication System (PACS) aims to replace conventional analogue film and paper clinical request forms and reports with a completely computerized electronic network whereby digital images are viewed on monitors in conjunction with the clinical details of the patient and the associated radiological report displayed in electronic format.  The ROLE OF DICOM: Digital Imaging and Communications in Medicine (DICOM) is a standard for handling, storing, printing, and transmitting information in medical imaging. It includes a file format definition and a network communications protocol. DICOM enables the integration of scanners, servers, workstations, printers, and network hardware from multiple manufacturers into a picture archiving and communication system (PACS). The different devices come with DICOM conformance statements which clearly state the DICOM classes they support. DICOM has been widely adopted by hospitals .

?

Add a comment

Related presentations

Related pages

Computed radiography - Wikipedia, the free encyclopedia

Computed radiography (CR) is often distinguished from Direct Radiography (DR). CR and DR have many similarities. Both CR and DR use a medium to capture x ...
Read more

CR/DR - What does CR/DR stand for? The Free Dictionary

Acronym Definition; CR/DR: Change Request/Discrepancy Report: Want to thank TFD for its existence? Tell a friend about us, add a link to this page, or ...
Read more

Dr and Cr Rules

Dr and Cr Rules . There are five types of accounts: Assets; Liabilities; Owner's Equity; Revenue; Expenses; The following types INCREASE if you DEBIT the ...
Read more

DR/CR - What does DR/CR stand for? The Free Dictionary

Acronym Definition; DR/CR: Debit Record/Credit Record (accounting) Want to thank TFD for its existence? Tell a friend about us, add a link to this page, or ...
Read more

MVZ Crailsheim | Dr. med. Helmut Kopp

Facharzt für Allgemeinmedizin; Homöopathie, Akupunktur, Palliativmedizin, psychosomatische Grundversorgung. Weitere Tätigkeitsschwerpunkte: Reisemedizin ...
Read more

CR / DR - EVERX

Everx Pty. Ltd. specializes in Refurbished Medical Equipment. BROWSE BY CATEGORY. CT; MRI; Ultrasound/Color Doppler; Cath/Angio Lab; Mammography
Read more

MVZ Crailsheim | Dr. med. Andreas Freytag

Facharzt für Chirurgie, Orthopädie mit Schwerpunkt Unfallchirurgie, Notfallmedizin, Zertifizierter Fußchirurg (GFFC), D-Arzt E_Mail: dr.freytag@mvz-cr.de
Read more

CR and DR State X-ray Inspection Protocol

Publication No. E-10-2 COMPUTED RADIOGRAPHY (CR) AND DIGITAL RADIOGRAPHY (DR) STATE X-RAY INSPECTION PROTOCOL January 2010 Published by Conference of ...
Read more

Gebrauchte CR & DR Systeme für Veterinäre > Laser ...

Günstige CR & DR Gebraucht-Systeme für Veterinäre - 12 Monate Garantie
Read more