X-ray beam emission

Question 1

X-ray beam emission in what direction?

Answer 1

X-rays are emitted isotropically (in all directions).

The only portion that is diagnostically useful is the part directed toward the patient through the tube window

Question 2

Primary (incident) radiation, or Primary Beam.

Answer 2

The only portion that is diagnostically useful is the part directed toward the patient through the tube window

Question 3

Remnant Radiation

Answer 3

The portion of the x-ray beam that exits the patient and strikes the film and forms anatomical image.

Question 4

Collimation

Answer 4

is a restriction of the primary beam to the area of interest.

Question 5

Central ray (CR)

Answer 5

is the center of the x-ray beam that interacts with the image receptor.

Question 6

radiographic films demonstrate four basic qualities

Answer 6

1. Sufficient density (the overall blackening of the film).
2. Proper contrast (differences between extreme blacks and whites on the film).
3. Maximum detail (sharpness of contour lines).
4. Minimum distortion and magnification (all films have magnification because we radiograph three-dimensional (3-0) objects and place them as two-dimensioned image).

Question 7

Source-Image Distance (SID) (FFD)

Answer 7

The distance between the x-ray tube and the film (image) is called the source-image distance or SID, or the focus (Focal) film distance (FFD). It is typically 40” or 72” for standardization, depending on the exam.

Question 8

Object-Image Distance (OID)

Answer 8

The distance between the structure inside the patient’s body that is being radiographed and the place where the image is formed, which is usually at the image receptor is called the object-image distance (01D). Another term for the same thing object-film distance (OFD). We will mostly use (010)

Question 9

Source-Object Distance (SOD)

Answer 9

The last distance is the distance form the x-ray tube to the object. This distance is called the source-object distance (SOD), or the focus­ object distance (FOO).

*(SSD-Source-to-skin distance, shall not be less than 12” and should not be less than 15”)

Question 10

Source-image distance (SID)

Answer 10

The distance between the x-ray tube and the image receptor

Question 11

Object-image distance (01D)

Answer 11

The distance between the object and image receptor:

Question 12

Source-object distance (SOD)

Answer 12

The distance between the x-ray tube and object: