RTE 015 P1.1

Radiographic Positioning

The study of patient positioning performed for radiographic demonstration or visualization of specific bidy parts on image receptors (IRs)

Radiography

The process and procedures of producing a radiograph

X-ray film/ Film

The physical piece of material on which a latent radiographic image is stored.

Radiograph

Includes the recording medium and the image. Is displayed on viewbox or monitor.

Image receptor (IR)

Device that captures the radiographic image that exits the patient. Refers to both film-screen cassettesand digital acquisition devices.

Central ray (CR)

The centermost portion of the x-ray beam emitted from the x-ray tube—the portion of the x-ray beam that has the least divergence.

Five General Functions of Radiographic Examination

1. Positioning of the body part

2. Application of Radiation Protection

3. Selection of exposure factors

4. Instructions to the patient

5. Processing of the IR

Anatomical Position

Reference position that defines specific surfaces and planes of the body

Anatomical Position

1. An upright position

2. Arms abducted slightly (down)

3. Hands by side with palms forward

4. Head and feet together and directed straight ahead

Viewing Radiographs

General rule: Patient is facing the VIEWER, with the patient in the ANATOMIC POSITION

CT, MRI, and Sonography

Emphasizes sectional anatomy, which also involves the primary body planes and sections

Planes

Straight line surface connecting two points

4 Common planes

1. Sagittal

2. Coronal

3. Horizontal

4. Oblique

Sagittal Plane

Any longitudinal plane that divides the body into right and left parts. Any plane parallel to the midsagittal or median plane is called a SAGITTAL PLANE

Midsagittal plane/ Median plane

Midline sagittal plane that divides the body into equal right and left parts. It passes approximately through the SAGITTAL SUTURE of the skull

Coronal Plane/ Frontal plane

Any longitudinal plane that divides the body into anterior and posterior parts. Any plane parallel to the midcoronal or frontal plane is called CORONAL PLANE

Midcoronal plane

Divides the body into approximately equal anterior and posterior parts. It passes approximately through the CORONAL SUTURE of the skull

Horizontal/ Axial/ Transverse Plane

Any transverse plane that passes through the body at right angles to a longitudinal plane, dividing the body into superior and inferior portions

Oblique plane

A longitudinal or transverse plane that is at an angle or slant and is not parallel to the sagittal, coronal, or horizontal plane

Planes of the skull

1. Base plane of the skull

2. Occlusal Plane

Base plane of the skull (aka?)

Frankfort horizontal plane or Reid's baseline (RB)

Base Plane of the Skull

This precise transverse plane is formed by connecting the lines from the INFRAORBITAL MARGINS (inferior edge of bony orbits) to a superior margin of the EXTERNAL AUDITORY MEATUS (EAM), the external opening of the ear

Base Plane of the Skull

Used in orthodontics and cranial topography to measure and locate specific cranial points or structures

Occlusal Plane

This horizontal plane is formed by the biting surfaces of tge upper and lower teeth with jaws closed

Occlusal Plane

Used as a reference plane of the head for the cervical spine and skull radiography

Posterior/ Dorsal

The back half of the patient. Includes the bottoms of the feet and the backs of the hands as demonstrated in the anatomic position

Anterior/Ventral

Front half of the patient. Includes the tops of e feetand the fronts or palms of the hands in the anatomic position

Terms for Surfaces of the Hands and Feet

1. Plantar

2. Dorsal

3. Palmar

Plantar

The sole or posterior surface of the foot

Dorsal

Foot dorsal/ Dorsum pedis: Top/anterior surface of the foot

Hand dorsal/ Dorsum manus: Back/posterior surface of the foot

Palmar

Palm of thw hand. Ventral or anterior surface of the hand. Aka VOLAR

Projection

Positioning term that describes the direction or path of he CR of tge x-ray beam as it passes through the patient, projecting and image onto the IR.

6 Common projection terms

1. PA Projection

2. AP Projection

3. AP Oblique projection

4. PA Oblique projection

5. Mediolateral Projection

6. Lateromedial Projection

Posteroanterior (PA) Projection

Projection of the CR from posterior to anterior

Enters: posterior surface

Exits: anterior surface

Anteroposterior (AP) Projection

Projection of CR from anterior to posterior, the opposite of PA

Enters: anterior surface

Exits: posterior surface

AP Oblique Projection

An AP projection of the upper or lower limb that is rotated. Is NOT a true AP projection and must include a qualifying term that indicates which way it is rotated (medial/lateral rotation)

Enters: anterior surface

Exits: posterior surface

PA Oblique Projection

A PA projection of the upper or lower limb that is rotated. Is NOT a true PA projection, and must include qualifying term that indicates which way it is rotated.

Enters: posterior surface

Exits: anterior surface

Mediolateral and Lateromedial Projection

Medial and lateral sides are determined with the patient in the anatomic position.

Mediolateral Projection

CR direction

Enters: medial side

Exits: lateral side

Lateromedial Projection

CR direction

Enters: lateral side

Exits: medial side

8 General Body Positions

1. Supine

2. Prone

3. Erect (upright)

4. Recumbent (reclining)

5. Trendelenburg position

6. Fowler position

7. Sim's position

8. Lithotomy position

Supine

Aka DORSAL RECUMBENT

Lying on the back, facing upward

Prone

Aka VENTRAL RECUMBENT

Lying on abdomen, facing downward (head may be turned to one side)

Erect (upright)

Upright position, either standing or sitting

Recumbent (reclining)

Lying down in any position (nearest to the table, i think…)

1. Dorsal recumbent

2. Ventral recumbent

3. Lateral recumbent

Trendelenburg position

Recumbent position with the body tilted with the HEAD LOWER than the feet.

Fowler position

Recumbent position with the body tilted with the HEAD HIGHER than the feet.

Sim's position (Semiprone position)

Recumbent oblique position with the patient lying on the left anterior side, with the right knee and thigh flexed and left arm extended down behind the back

Modified Sim's position

Used for:

Rectal tube for Barium Enema

Lithotomy position

Recumbent (Supine) position with knees and hip flexed and thighs ABDUCTED and rotated EXTERNALLY, supported by ankle supports.

Lithotomy position

Position seen frequently in the SURGICAL SUITE for certain URINARY studies. Also used in LABOR.

Specific Body Positions

1. Lateral position

2. Oblique position

a. Left Posterior Oblique (LPO) Position

b. Right Posterior Oblique (RPO) Position

c. Left Anterior Oblique (LAO) Position

d. Right Anterior Oblique (RAO) Position

3. Decubitus position

a. Left Lateral Decubitus Position- AP/PA projection

b. Right Lateral Decubitus Position- AP/PA projection

c. Dorsal Decubitus position- Left/Right Lateral (projection?)

d. Ventral Decubitus position- Left/Right Lateral (projection?)

Specific Body Position

Second way the term position is used in radiography. Described by the body part CLOSEST to the IR (oblique and lateral) or by the SURFACE on which the patient is lying (decubitus)

Lateral Position

Refers to the side of, or a side view. Described by the part closest to the IR or the body part from which the CR exits.

True Lateral Position

At 90°/ perpendicular/ or right angle, to a true AP/PA projection.

Example:

Right lateral position= Right side of the body closest to the IR

Oblique Position

An angled position in which neither the sagittal nor the coronal body plane is perpendicular or at a right angle to the IR. Is NOT a true lateral.

Left Posterior Oblique (LPO) Position & Right Posterior Oblique (RPO) Position

Can be demonstrated in both erect and recumbent positions.

LPO CR exits: Left posterior aspect of the body

RPO CR exits: Right poster aspect of the body

Can be referred to as AP OBLIQUE PROJECTIONS, but requires a specific position clarifier such as LPO/RPO position

Left Anterior Oblique (LAO) & Right Anterior Oblique (RAO) Positions

Can be erect or recumbent general body positions.

LAO CR exits: Left anterior aspect of the body

RAO CR exits: Right anterior aspect of the body

Can be described as PA OBLIQUE PROJECTIONS, clarifier is added (LAO/RAO positions)

Decubitus (Decub) Position

Means to “lie down” / “ lying down” onba horizontal surface (the surface in which the body is resting)

Back (dorsal)

Front (ventral)

Side (left/right lateral)

Decubitus (Decub) Position

Is always performed with the CR horizontal

Decubitus (Decub) Position

Essential for detecting air-fluid levels/ free air in the body cavity. Performed when pt can't assume erect position.

Left or Right Lateral Decubitus Position— AP/PA Projection

The patient lies on the side, and the x-ray beam is directed HORIZONTALLY. From anterior to posterior (AP) or posterior to anterior (PA).

Note:

• Qualifying term ( AP/PA Projection)- important in decubitus to denote the CR direction

• Decub position is identified according to the DEPENDENT SIDE (side down) and the AP/PA projection identification

Dorsal Decubitus Position— Left/Right Lateral

Patient is lying on the posterior surface with the x-ray beam directed HORIZONTALLY.

CR exits: Side closest to IR (Left/ Right)

Note: position is named according to the surface with the pt is lying & by the side closest to the IR (Left/Right)

Ventral Decubitus Position— Left/Right Lateral

Patient is lying on the anterior surface with the x-ray beam directed horizontally, exiting from the sode closest to the IR.

Note: position is named according to the surface with the pt is lying & by the side closest to the IR (Left/Right)

8 Additional Special Use Projection Terms

1. Axial Projection

2. Inferosuperior and Superoinferior Axial Projections

3. Tangential Projection

4. AP Axial Projection- Lordotic Position

5. Transthoracic Lateral Projection (Right Lateral Position)

6. Dorsoplantar and Plantodorsal Projections

7. Parietoacanthial and Acanthioparietal Projections

8. Submentovertical (SMV) and Verticosubmental (VSM) Projections

Axial Projection

Refers to the long axis of a structure or part (around which a rotating body turns or is arranged).

Special application—AP or PA axial:

Axial Projection

Used to describe any angle of the CR of 10 ° or more along the long axis of the body or body part.

Semiaxial projection

“partly“ axial, more accurately describes any angle along the axis that is not truly perpendicular or parallel to the long axis .

Axial Projection

Towne’s Method (x-ray tube is angled)

Inferosuperior Axial Projections

Frequently performed for the shoulder and hip, where the CR enters below or inferiorly and exits above or superiorly.

Superoinferior Axial Projection

Opposite of Inferosuperior Axial Projection, is performed in SPECIAL NASAL BONE projection

Tangential Projection

This is a special use of the term projection to describe the central ray that SKIMS A BODY PART to project the anatomy into profile and free of superimposition of surrounding body structures.

Tangential

Means touching a curve or surface at only one point

Tangential Projection

Applied in:

1. Tangential projection of ZYGOMATIC ARCH

2. Tangential projection of PATELLA

AP Axial Projection- Lordotic Position

This is a specific AP axial chest projection for demonstrating the APICES of the lungs.

AP Axial Projection- Lordotic Position

AP Axial Chest Projection

AP Lordotic Position

AP Axial Projection- Lordotic Position

The long axis of the body rather than the CR is angled. The lumbar lordotic curvature is exaggerated, making this a descriptive term for this special chest projection.

Transthoracic Lateral Projection (Left/Right Lateral Position)

A lateral projection THROUGH the thorax.

Transthoracic Lateral Projection (Left/Right Lateral Position)

Requires a qualifying positioning term (right or left lateral position) to indicate which shoulder is closest to the IR and is being examined.

This is a special adaptation of the projection term, indicating that the CR passes through the thorax even though it does NOT include an entrance or exit site.

Dorsoplantar and Plantodorsal Projections

These are secondary terms for AP or PA projections of the foot.

Dorsoplantar (DP) Projection

Describes the path of the CR from the anterior surface to the posterior surface of the foot.

Valor

Other Term for Palmar or Anterior surface of the hand

Axial Plantodorsal Projection (PD)

A special plantodorsal projection of the heel bone (calcaneus). The angled CR enters the posterior surface of the foot and exits the anterior surface.

Parietoacanthial Projection

CR direction

Enters: CRANIAL PARIETAL BONE

Exits: ACANTHION (junction of nose and upper lip).

Acanthioparietal Projection

CR direction

Enters: ACANTHION (junction of nose and upper lip)

Exits: CRANIAL PARIETAL BONE

PA Waters/ Waters Method

Parietoacanthial projection, METHOD name

Commonly used to visualize the FACIAL BONES

AP Reverse Waters/ Reverse Waters Method

Acanthioparietal Projection, METHOD name

Visualize the facial bones (UNCOMMON)

Submentovertical (SMV) and Verticosubmental (VSM) Projections

These projections are used for the SKULL and MANDIBLE

Submentovertical (SMV) Projection

CR direction

Enters: Below the chin (mandible)/ Mentum

Exits: At the vertex/ top of the skull

Verticosubmental (VSM) Projection

Opposite of SMV (UNCOMMON)

CR direction

Enters: Top of the skull/ at the vertex

Exits: Below the (chin) mandible/ Mentum

12 Relationship Terms

• Medial vs. Lateral Projections

• Proximal vs. Distal

• Cephalad vs. Caudad

• Interior vs. Exterior

• Superficial vs. Deep

• Ipsilateral vs. Contralateral

Medial vs. Lateral Projections

Refers to toward versus away from the center, or median plane.

Medial

In the anatomic position, it is the aspect of any body part that is in the “inside” part closest to the median plane

Lateral

Means away from the center, or away from the median plane or midline of the body.

Proximal

Means near the source/ beginning/ trunk

Distal

Means away from. Far from the beginning/ trunk of the body

Cephalad

Means toward the head end of the body. In human anatomy it can be described as SUPERIOR.

Cephalad or Cephalic

Means “head“ or “toward the head“

Cephalad angle

Any angle toward the head end of the body.

Caudad

Means away from the head end of the body. In human anatomy it can be described as INFERIOR.