Introduction of Radiographic Technology I.Radiographic Terminology II.Basic Imaging Principles III.Positioning Principles IV.Digital Imaging

I. Radiographic Terminology General Terms General Terms 1. Radiograph 2. Radiography 3. Radiograph vs. x-ray film 4. Radiographic images 5. Radiographic examination or procedure procedure 6. Anatomic position

I. Radiographic Terminology Body Plane 、 Section and Lines Body Plane 、 Section and Lines Sagittal plane Sagittal plane Coronal plane Coronal plane Horizontal plane Horizontal plane Oblique plane Oblique plane Base plane Base plane Occlusal plane Occlusal plane

I. Radiographic Terminology Body Surfaces and Parts Body Surfaces and Parts For the body For the body anterior anterior posterior posterior For the hands and feet For the hands and feet plantar plantar palmar palmar dorsum dorsum

I. Radiographic Terminology General Body Positions General Body Positions Supine Supine Prone Prone Erect (stand or sit) Erect (stand or sit) Recumbent Recumbent Lying down in any position Dorsal (supine) Dorsal (supine) Ventral (prone) Ventral (prone) Lateral Lateral

I. Radiographic Terminology General Body Positions General Body Positions Trendelenburg Trendelenburg Sim ’ s position Sim ’ s position Fowler ’ s position Fowler ’ s position Lithotomy position Lithotomy position

I. Radiographic Terminology Specific Body Positions Specific Body Positions The body part closest to the IR (oblique and lateral) or by the surface on which the patient is lying The body part closest to the IR (oblique and lateral) or by the surface on which the patient is lying Lateral Lateral Right/Left Right/Left Oblique Oblique LPO/RPO LPO/RPO LAO/RAO LAO/RAO

I. Radiographic Terminology Decubitus (Lie on a horizontal surface and always used with horizontal x-ray beam) Decubitus (Lie on a horizontal surface and always used with horizontal x-ray beam)

I. Radiographic Terminology Radiographic Projection Radiographic Projection The direction or path of the CR of the x-ray beam Anteroposterior Anteroposterior Posteroanterior Posteroanterior AP or PA Oblique AP or PA Oblique Mediolateral or Lateromedial Mediolateral or Lateromedial

I. Radiographic Terminology Additional Special Use Projection Terms Additional Special Use Projection Terms Axial Axial Superoinferior axial Superoinferior axial Inferosuperior axial Inferosuperior axial AP/PA axial AP/PA axial

I. Radiographic Terminology Tangential Tangential AP axial (Lordotic) AP axial (Lordotic) Transthoracic lateral Transthoracic lateral

I. Radiographic Terminology Dorsoplantar / Plantodorsal Dorsoplantar / Plantodorsal Parietoacnthial / Acanthioparietal Parietoacnthial / Acanthioparietal Submentovertex /Verticosubmental Submentovertex /Verticosubmental

I. Radiographic Terminology Relationship Terms Relationship Terms Meidal vs. Lateral Meidal vs. Lateral Proximal vs. Distal Proximal vs. Distal Cephalad vs.Caudad Cephalad vs.Caudad

I. Radiographic Terminology Terms Related to Movements Terms Related to Movements Flexion/Extension/Hyperextension Flexion/Extension/Hyperextension Ulnar deviation/Radial deviation Ulnar deviation/Radial deviation Dorsiflexion/Plantar flexion of foot Dorsiflexion/Plantar flexion of foot

I. Radiographic Terminology Terms Related to Movements Terms Related to Movements Eversion (Valgus)/Inversion(Varus) Eversion (Valgus)/Inversion(Varus) Medial /Lateral Rotation Medial /Lateral Rotation

I. Radiographic Terminology Terms Related to Movements Terms Related to Movements Abduction/Adduction Abduction/Adduction Supination/Pronation Supination/Pronation Protraction/Retration Protraction/Retration

I. Radiographic Terminology Terms Related to Movements Terms Related to Movements Elevation/Depression Elevation/Depression Circumduction Circumduction Tilt/Rotation Tilt/Rotation

I. Radiographic Terminology Summary of Potentially Misused Terms Summary of Potentially Misused Terms Position Position restricted to the discussion of the patient’s physical position Projection Projection restricted to the discussion of the path of the central ray View View restricted to the discussion of the a radiograph or image

II. Basic Imaging Principles Radiographic Criteria Radiographic Criteria Structures Show(1~6) Structures Show(1~6) Position Position Collimator and CR Collimator and CR Exposure Criteria Exposure Criteria Image Markers Image Markers a c b

Image Markers and Patient Identification Image Markers and Patient Identification Patient ID and Date Patient ID and Date Anatomic side marker Anatomic side marker Additional markers or Identification Additional markers or Identification II. Basic Imaging Principles

Radiographic Technique and Image Quality Radiographic Technique and Image Quality Exposure factors Exposure factors kVp kVp mA mA S (excepted when AEC is used ) S (excepted when AEC is used ) Image Quality Factors Image Quality Factors Density Density Contrast Contrast Detail Detail Distortion Distortion II. Basic Imaging Principles

Density Density Definition ： the amount of blackening of the processed image Definition ： the amount of blackening of the processed image Controlling factor ： mAs / kVp / SID Controlling factor ： mAs / kVp / SID Change rule ： Underexposure  Doubling mAs Change rule ： Underexposure  Doubling mAs Exception ： DR and CR (controlled by image process technique) Exception ： DR and CR (controlled by image process technique)

II. Basic Imaging Principles Contrast Contrast Definition ： the difference in density on adjacent areas of a radiographic image Definition ： the difference in density on adjacent areas of a radiographic image Purpose ： make the anatomic detail of a radiographic image more visible Purpose ： make the anatomic detail of a radiographic image more visible Controlling factor ： kVp Controlling factor ： kVp (15% increase as mAs double) (15% increase as mAs double)

II. Basic Imaging Principles Detail Detail Definition ： the visible sharpness of structure on the image Definition ： the visible sharpness of structure on the image Controlling factor Controlling factor Geometric factors : focal spot size/SID/OID Geometric factors : focal spot size/SID/OID Film/Screen Speed Film/Screen Speed Motion Motion

II. Basic Imaging Principles Distortion Distortion Definition ： the misrepresentation of object size or shape as projected onto film (because of beam divergence and SID) Definition ： the misrepresentation of object size or shape as projected onto film (because of beam divergence and SID)

II. Basic Imaging Principles Distortion Distortion Controlling factor Controlling factor SID SID OID/Focal spot size OID/Focal spot size

II. Basic Imaging Principles Alignment (object 、 film 、 CR) Alignment (object 、 film 、 CR)

Anode Heel Effect Anode Heel Effect Intensity of cathode > anode Pronounced at Pronounced at Shorter SID Shorter SID Larger IR Larger IR Small focal spot Small focal spot II. Basic Imaging Principles

III. Positioning Principles Professional Ethics and Patient Care Professional Ethics and Patient Care CAMRT ( ) CAMRT ( ) Canadian Association of Medical Radiation Technologists Canadian Association of Medical Radiation Technologists ASRT ( ) ASRT ( ) American Society of Radiological Technologists American Society of Radiological Technologists Protocol and Order for General Diagnostic Radiographic Procedures Protocol and Order for General Diagnostic Radiographic Procedures Room and Exam Preparation Room and Exam Preparation

III. Positioning Principles Positioning Method Positioning Method Fixed vs. Floating tabletop Fixed vs. Floating tabletop Cassette tray and Bucky grid Cassette tray and Bucky grid Beam restricting device Beam restricting device Illuminated adjustable collimator Illuminated adjustable collimator Positive Beam Limitation (PBL) Positive Beam Limitation (PBL)

III. Positioning Principles Positioning Sequences Positioning Sequences Traditional Radiography Traditional Radiography Step1 Step3 Step4 Step2

Table Table With bucky With bucky no bucky no bucky Standing bucky Standing bucky

III. Positioning Principles Essential Projections Essential Projections Routine (Basic) Projections Routine (Basic) Projections Commonly taken on all patients who can cooperate fully Commonly taken on all patients who can cooperate fully Special (Alternate) Projections Special (Alternate) Projections Better demonstrate specific anatomic or certain pathology Better demonstrate specific anatomic or certain pathology The patients who can ’ t cooperate fully The patients who can ’ t cooperate fully

III. Positioning Principles Principle for Determining Positioning Routine Principle for Determining Positioning Routine A minimum of two projections A minimum of two projections Problem of anatomic structures Problem of anatomic structures being superimposed being superimposed Localization of lesions or foreign bodies Localization of lesions or foreign bodies Determination of alignment of fracture Determination of alignment of fracture A minimum of three projections A minimum of three projections Skeletal system involving joints Skeletal system involving joints AP 、 PA 、 Oblique AP 、 PA 、 Oblique

III. Positioning Principles Topographic Positioning Landmarks Topographic Positioning Landmarks Done gently Done gently Patient should be informed Patient should be informed Body Habitus Body Habitus

III. Positioning Principles Viewing Medical Images Viewing Medical Images Radiographic Images Radiographic Images AP/PA/Oblique AP/PA/Oblique Viewing as patient is facing the viewer Viewing as patient is facing the viewer Marked by R/L Marked by R/L

III. Positioning Principles Lateral Lateral Viewing from the same perspective as the x-ray tube Viewing from the same perspective as the x-ray tube Marked R/L by the side of the patient closet to the IR Marked R/L by the side of the patient closet to the IR Decubitus chests and abdomen Decubitus chests and abdomen Viewing from the same perspective as the x-ray tube Viewing from the same perspective as the x-ray tube Crosswise and p ’ t upside on view box upside Crosswise and p ’ t upside on view box upside Upper/lower limb Upper/lower limb R/L marker appears right-side-up R/L marker appears right-side-up Limbs hanging down Limbs hanging down Digits up Digits up

III. Positioning Principles CT or MRI Images CT or MRI Images The patient ’ s right is to the viewer ’ s left The patient ’ s right is to the viewer ’ s left

IV. Digital Imaging PACS (Picture Archiving and Communication System) PACS (Picture Archiving and Communication System)

IV. Digital Imaging CR (Computed Radiography) CR (Computed Radiography) Key components Key components Image plate (repeatedly) Image plate (repeatedly) IP reader (laser scanner, 20s) IP reader (laser scanner, 20s) Workstation Workstation Exposure factor( AEC is not used) Exposure factor( AEC is not used) Compensation 500% overexposure ， Compensation 500% overexposure ， 80% underexposure 80% underexposure Positioning consideration Positioning consideration Center sampling technique Center sampling technique Accurate and close collimation Accurate and close collimation Lead masking for multiple images Lead masking for multiple images Grid Grid

IV. Digital Imaging DR (Digital Radiography ) DR (Digital Radiography ) Flat panel receptor (direct conversion method ) Flat panel receptor (direct conversion method ) Digital Bucky grid 17 ” *17 ” Digital Bucky grid 17 ” *17 ” Automatic Exposure Control (AEC) Automatic Exposure Control (AEC) kVp ” 、 ” m A ” manual kVp ” 、 ” m A ” manual “ s ” auto “ s ” auto

IV. Digital Imaging DR in CGMH DR in CGMH Digital image unit Digital image unit

Quality Control for Processor Set up initial standard (base line) Set up initial standard (base line) In most stable condition of the processor In most stable condition of the processor Individual O.D. of 21 steps (average of five days measurements) Individual O.D. of 21 steps (average of five days measurements) Find O.D. ≧ 1.2  Mid-density (MD) and Mid-step# Find O.D. ≧ 1.2  Mid-density (MD) and Mid-step# Find O.D. ≧ 2.2  High-density (HD) and High-step# Find O.D. ≧ 2.2  High-density (HD) and High-step# Find O.D. ≧ 0.45  Low-density (LD) and Low-step# Find O.D. ≧ 0.45  Low-density (LD) and Low-step# Daily QA Daily QA MD < ±0.15 (measurement - base line) MD < ±0.15 (measurement - base line) DD < ±0.15 (measurement - base line) DD < ±0.15 (measurement - base line) (DD=HD-LD) (DD=HD-LD)