PACS

Question 1

What are the advantages of digital image?

Answer 1

• image reconstruction
• image reformatting
• wide dynamic range
• image processing
• fast storage and retrieval
• fast and high quality image distribution
• controlled viewing
• image analysis

Question 2

What affects digital image quality?

Answer 2

1. Resolution (high matrix, small pixel size = good resolution)
2. Noise
3. Detective quantum efficiency (DQE) -> how well a system converts incoming data to output viewing device (perfect = 1, realistic = 0.3-0.7)

Question 3

What is PACS?

Answer 3

• picture archiving and communications system

- is electeonic method of storing and accessing medical imaging examinations

Question 4

What are advantages of PACS?

Answer 4

• remote access
• long term archiving
• immediate access to image
• improved image interpretation
• cost

Question 5

What are the disadvantages of PACS?

Answer 5

• image quality dependent on monitor quality
• initial cost
• transition period

Question 6

What is RIS?

Answer 6

• radiology information system

- data for radiology department to store patient data and images

Question 7

What does RIS include?

Answer 7

• patient registration and scheduling
• list and tracking capabilities
• request and document scanning
• reporting
• image storage

Question 8

What is HIS?

Answer 8

• historical information system

- stores inpatient data working with RIS and PACS

Question 9

What does HIS include?

Answer 9

• patient tracking
• images and reports
• hospital administration (health care funds)
• referring doctor

Question 10

What is DICOM?

Answer 10

• Digital imaging and communciation in medicine

- standard computer language so all types and brands of equipment are the same

Question 11

What needs to be checked before sending an image to PACS?

Answer 11

• patient name, ID and DOB
• date and departmental details
• sidemarkers and orientation
• image is of diagnostic quality

Question 12

What is data integrity?

Answer 12

• refers to accuracy and consistency of patient images and reports
• physical and logical

Question 13

What is physical integrity?

Answer 13

• end of life (x-ray, PACS)
• power outages
• natural disaster
• system design faults

Question 14

What is logical integrity?

Answer 14

• images and reports belonging to the correct painters

- package contains enough images and report information

Question 15

How can data integrity be comprimised?

Answer 15

• human error
• transfer errors
• bugs/viruses
• comprised hardware
• physical compromise to device

Question 16

What is ALARA?

Answer 16

• as low as reasonably achievable

Question 17

What are the three levels of dose?

Answer 17

1. Absorbed dose = energy deposited in a Kg of substance by RT
2. Equivalent dose = absorbed dose weighted for harmful effects of different radiation
3. Effective dose = equivalent dose weighted for harm of different tissues

Question 18

What are the dose limits?

Answer 18

• occupational: 20mSv per year no more then 50 in one year

- public: 1 mSv per year

Question 19

What is protection of the patient?

Answer 19

• correct patient and site
• limit number of exposures (avoid repeats)
• corrext SID and exposure selection
• adequate filter
• use lead shielding

Question 20

What is the protection for the operator?

Answer 20

• stay behind protective barrier
• minimise time and exposure
• maximise distance from x-ray source
• wear protective clothes and TLD
• do not hold patient