CT Final

Question 1

1. How many images acquired in 16 slice cat scan
2. Before contrast, check ________ functions
3. Increasing kVp = ________ dose
4. _______ is Father CAT Scan

Answer 1

1. 16
2. Renal (Kindey) function - BUN/Creatine
3. Increased Dose
4. Houndsfield

Question 2

1. CAT Scan produced in what plane?
2. 3 Step Image Creation
3. First Gen took how long for 1 image?
4. Current generation used:

Answer 2

1. Axial
2. Acquisition, Reconstruction, Storage/Display
3. 5 min PER image (not whole scan)
4. Third

Question 3

1. What generation for cardiac?
2. What beam did first generation use?
3. X-Rays developed in what year?
4. What converts analog to digital image?

Answer 3

1. Fifth - EPCT
2. Pencil Beam
3. 1895
4. ADC

Question 4

1. Hounsfield Unit for water:
2. What are Hounsfield Unit?
3. What is in main component in matrix called
   - What diminution is it?
4. What was main limitation of radiography?

Answer 4

1. 0
2. Number assigned to gray shades/pixel depending on anatomy
3. Pixel - 2D
   - Voxel is 3D
4. Overlapping Anatomy (main reason moved from xray to CT)

Question 5

1. CT Number (Housfield) Depend on what image quality:
2. Widow Width Controls
3. Window Level Controls
4. Coronal and Sagittal Image Formation Is apart of what process?

Answer 5

1. Linear Attenuation Coefficient
2. Contrast (Density)
3. Brightness
4. Post-Processing (Acquire data in axial and in post process can change to other planes)

Question 6

1. Which generation had full rings?
2. How is spiral-Helical made possible?
3. Are x-ray tubes similar in x-ray and CT
4. Type of filters used in CT

Answer 6

1. 4
2. Slip-rings
3. NO - CT withholds / dissipates more heat

4.. Bowtie Filters (considers patient anatomy)

Question 7

1. Do detector collimation reduce dose?
2. Wider Width = _________
3. Sharp difference in black and white on image = ______ contrast.
   - Is this a good image?
4. Unit for doses:

Answer 7

1. No - they only filter out scatter reaching detectors / control slice thickness
2. Better Contrast
3. Sharp / High
   
   • No / Depend on anatomy (need more grays for pathology)
4. IMAGE
   Absorbed Dose= RAD/ Gray

Question 8

1. Absorbed Dose, Effective Dose & Exposure

2/3. Compare of Stotistic & Deterministic effects

Answer 8

1. IMAGE
2. Stotatstic = Low level radiation exposure
   
   • probability
     - Leukemia / Hereditary
3. Determministic = Severity increases with increased dose
   - has threshold

Question 9

1. Normal Creatin:
   Normal Uria (BUN):
2. Main cause of radiation reaching tech
3. Name of x-ray tube used in CT
4. Process of sampling data

Answer 9

1. .6-1.2
   - 6-25
2. Patient / Scatter
3. Radon X-Ray Tube
4. interpolation

Question 10

1. Radiation _______ with decreased detector rows

2.

Answer 10

1. Increase
   - INVERSE proportional