Projection

Question 0

AP projection (anteroposterior)

Answer 0

A perpendicular central ray enters the anterior body surface and exits the posterior body surface. In a true AP projection without rotation, the CR is perpendicular to the coronal plane and parallel to the MSP

Question 1

What does projection refer to?

Answer 1

The path of the central ray.

Question 2

An AP projection of the foot is also called:

Answer 2

a dorsoplantar projection

Question 3

PA projection (posteroanterior)

Answer 3

A perpendicular central ray enters the posterior surface of the body and exits the anterior body surface.

Question 4

AP oblique projection

Answer 4

During an oblique projection the CR enters the body or body part from a side angle following an oblique plane. An AP oblique projection enters the anterior surface. An AP oblique projection of the upper or lower limbs must also include a qualifying term indicating which way it is rotated such as medial or lateral.

Question 5

PA oblique projection

Answer 5

During an oblique projection the CR enters the body or body part from a side angle following an oblique angle. A PA projection enters the posterior surface. A PA oblique projection of the upper or lower limbs must also include a qualifying term indicating which way it is rotated such as medial or lateral.

Question 6

Mediolateral and lateromedial projections

Answer 6

A lateral projection is described by the path of the CR. A Mediolateral projection enters the medial side and exits the lateral side. A lateromedial projection enters the lateral and exits the medial. (used with limbs)

Question 7

An AP projection of the foot is also called:

Answer 7

Dorsoplantar

Question 8

What three positions can PA projections be achieved in?

Answer 8

Seated, prone and lateral decubitus

Question 9

Axial projection

Answer 9

In an axial projection, there is longitudinal angulation of the central ray with the long axis of the body OR a specific body part. The angle must be greater than ten degrees.

Question 10

How can an axial projection be achieved when keeping a perpendicular central ray?

Answer 10

By angling the entire body or body part.

Question 11

Tangential Projection:

Answer 11

• Means touching a curve or surface at only one point.
• Describes a projection that merely skims a body part to project that part into profile and away from other body structures.

Question 12

Lordotic position - AP axial projection

Answer 12

Demonstrates the apices of the lungs. The long axis of the body is angled rather then the CR.

Question 13

Transthoracic lateral projection

Answer 13

A unique lateral projection through the thorax used for shoulder radiography. Requires a positioning term (right or left lateral position) to indicate which shoulder is closest to the IR & is being examined.

Question 14

Dorsoplantar and plantodorsal projections

Answer 14

Dorsoplantar (DP) describes the path of the CR from the dorsal surface to the plantar surface.
A special plantodorsal projection of the heel bone (calcaneus) is called an axial plantodorsal projection because the angled CR enters the plantar surface of the foot & exits the dorsal surface.

Question 15

Parietoacanthial and acanthioparietal projections

Answer 15

With the parietoacanthial projection, the CR enters the parietal bone and exits at the acanthion (junction of the nose and upper lip).
The opposite CR direction would describe the acanthioparietal projection. A.K.A. PA Waters and AP reverse Waters methods.

Question 16

Submentovertex (SMV) and verticosubmental (VSM) projections

Answer 16

For submentovertex, the CR enters below the chin, or mentum, and exits at the vertex or top of the skull.
The less common verticosubmental projection enters at the top of the skull and exits below the mandible.

Question 17

Cephalad

Answer 17

Refers to parts toward the head of the body.

Question 18

Caudad

Answer 18

Refers to parts away from the head of the body.

Question 19

True or false: when a range of central ray angles, such as 5 to 15 degrees, is recommended for a given projection, the term “axial” is used because the angulation could exceed 10 degrees.

Answer 19

True

Question 20

Lateral projection

Answer 20

A perpendicular CR enters one side of the body or body part, passes transversely along the coronal plane, and exits the opposite side.

Question 21

What terms are used with lateral projections of limbs?

Answer 21

Lateromedial or Mediolateral.

Question 22

Oblique projections

Answer 22

Enter the body or body part from a side angle following an oblique plane. Can be lateral, AP, or PA.

Question 23

True or false: All oblique projections are achieved by rotating the patient with the CR perpendicular to the IR.

Answer 23

False. Most, not all.

Question 24

Describe a right posterior oblique position.

Answer 24

It places the right posterior surface of the body closest to the IR and corresponds with the AP oblique projection.

Question 25

What must accompany an AP or PA oblique projection of the upper or lower limbs?

Answer 25

A qualifying term such as medial or lateral rotation.