Radiographic Positioning and
Radiologic Procedures II: Radiographic
Positioning Terminology
Anatomy - Answer- Is the term applied to the science of the structure of the body.
Physiology - Answer- Study of the function of body organs.
Osteology - Answer- Is the detailed study of the body of knowledge relating to the
bones of the body.
Projection - Answer- Is defined as the path of the central rays as it exits the x-ray
tube and goes through the patient to the IR.
Defined by the relationship formed between the central ray and the body as the
central ray passes through the entire body or body part.
Axial Projection - Answer- Refers to all projections in which the longitudinal
angulation between the central ray and the long axis of the body part is 10 degrees
or more.
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.
Tangential Projection - Answer- Central rays directed toward the outer margin of a
curved body surface to profile a body part just under the surface and project it free of
superimposition.
It is called "Tangential projection" because of the tangential relationship formed
between the central ray and the entire body or body part.
Lateral Projection - Answer- Passes transversely along the coronal plane and exits
on the opposite side.
Can enter from either side of the body or body part as needed for the examination.
A left lateral or right lateral position specifies the side of the body closest to the IR
and corresponds with side exited by the central ray.
Oblique Projection - Answer- Are achieved by rotating the patient with the central ray
perpendicular to the IR or by angling the central ray diagonally along the horizontal
plane rather than rotating the patient.
May enter from either side of the body and from anterior or posterior surfaces.
True Projections - Answer- Is often used in clinical practice.
True is used specifically indicate that the body part must be placed exactly in the
anatomic position.
Complex Projections - Answer- This may be defined by entrance and exit points and
by the central ray relationship to the body at the same time.
Radiologic Procedures II: Radiographic
Positioning Terminology
Anatomy - Answer- Is the term applied to the science of the structure of the body.
Physiology - Answer- Study of the function of body organs.
Osteology - Answer- Is the detailed study of the body of knowledge relating to the
bones of the body.
Projection - Answer- Is defined as the path of the central rays as it exits the x-ray
tube and goes through the patient to the IR.
Defined by the relationship formed between the central ray and the body as the
central ray passes through the entire body or body part.
Axial Projection - Answer- Refers to all projections in which the longitudinal
angulation between the central ray and the long axis of the body part is 10 degrees
or more.
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.
Tangential Projection - Answer- Central rays directed toward the outer margin of a
curved body surface to profile a body part just under the surface and project it free of
superimposition.
It is called "Tangential projection" because of the tangential relationship formed
between the central ray and the entire body or body part.
Lateral Projection - Answer- Passes transversely along the coronal plane and exits
on the opposite side.
Can enter from either side of the body or body part as needed for the examination.
A left lateral or right lateral position specifies the side of the body closest to the IR
and corresponds with side exited by the central ray.
Oblique Projection - Answer- Are achieved by rotating the patient with the central ray
perpendicular to the IR or by angling the central ray diagonally along the horizontal
plane rather than rotating the patient.
May enter from either side of the body and from anterior or posterior surfaces.
True Projections - Answer- Is often used in clinical practice.
True is used specifically indicate that the body part must be placed exactly in the
anatomic position.
Complex Projections - Answer- This may be defined by entrance and exit points and
by the central ray relationship to the body at the same time.
