Projections Terminology

Projections Terminology
• Projection – refers to the direction of the central ray which travels through the body.
• View – is used when discussing a radiographic image. “View’ is the exact opposite term of “projection”.
• Position – refers to the specific body position or act of placing the px in the desired position in relation to the film or cassette or even in the table.
• Oblique – px is rotated between lateral and prone or lateral and supine position. It is always at angled at 45 degrees.
• Decubitus – px is in recumbent position and usually implies the used of horizontal plane.
• AP Projection- central ray passes from the anterior to posterior aspect of the body.
• PA Projection- central ray passes from the posterior to the anterior aspect of the body.
• Left lateral projection- CR passes from one side to another. From head, chest and abdomen it is named to the nearest side of the body.
Example: Mediolateral
• PA oblique and projection – a.k.a RAO position.
• Axial Projection- longitudinal central ray angle of 10 degrees more with the long axis of the body or body part.
• Tangential- CR touches the structure at one point skimming it and producing a profile projection. It is opposite of axial.
Directional or Relationship Terminology
1. Anterior or Ventral – front or forward aspect of the body or body part.
2. Posterior or Dorsal – backward part of the body.
3. Medial or Mesial – towards the median plane or middle part of the body. Example: Spine is medial to the kidney.
4. Lateral – refers to the position away to the median plane or middle part of the body. It is the opposite of medial position.
Ex: kidneys are lateral to the spine.
5. Proximal – parts close to the point of origin or attachment.
Ex: elbow is proximal to the wrist.
6. Distal – parts furthest to the point of origin.
Ex: fingers are distal to the wrist.
7. Cephalad – termed as cephalic, cranial or superior.
- Pertaining to or towards the head.
8. Caudal – termed as inferior.
- Away from the head or towards the tail or feet.