Zarqa University Radiographic Technique 1 PDF

Zarqa University Faculty of Allied Medical Sciences Department of Medical Radiologic Technologies Radiographic Technique 1 Positioning Principles  Outline Radiographic criteria Image markers and patient ID Protocol and order for general radiographic procedures Positi...

Zarqa University Faculty of Allied Medical Sciences Department of Medical Radiologic Technologies Radiographic Technique 1 Positioning Principles  Outline Radiographic criteria Image markers and patient ID Protocol and order for general radiographic procedures Positioning methods and steps Positioning sequence and routine Essential projections Topographic positioning and landmarks  Radiographic Criteria Radiographic criteria format 1. Anatomy Demonstrated 2. Position 3. Collimation & CR 4. Exposure criteria 5. Image markers  Radiographic Criteria – Structures shown Which anatomical part should be clearly viewed. Example: Lat. forearm 1. Lateral projection of entire radius and ulna 2. Proximal row of carpals 3. Elbow 4. Distal end of humerus 5. Pertinent soft tissues  Radiographic Criteria – Position Describes two things: 1. Placement of body part in relation to the IR 2. Positioning factors that are important for the projection Example: Lat. forearm: 1. Ulna/radius aligned to long axis of IR 2. Elbow flexed 90 degree 3. No rotation from a true lateral position: a. Head of the ulna should be superimposed over the radius b. Humeral epicondyles should be superimposed  Radiographic Criteria – Collimation and CR Describes two factors. Where the collimation borders should be in relation to that body part. The location of the CR: it is especially important in the case of Joints Example: Lat. forearm: Collimation borders visible at skin margins along length of forearm with minimal collimation at both ends to ensure that essential joint anatomy is included. CR and center of collimation field to midpoint of radius and ulna.  Radiographic Criteria – Exposure Criteria Describes how exposure factors or technique can be evaluated for optimum exposure for that body part. 1. kVp 2. mA 3. Time (motion) Example: Lat. Forearm: Optimum density and contrast with no motion will visualize sharp cortical margins and clear, bony reticular marking and fat pads and stripes of the wrist and elbow joints  Radiographic Criteria – Image Markers Involves: 1. Patient ID 2. R or L side 3. Patient position 4. Time Example: PA wrist: as in the image, should be placed so that they are not superimposed over essential anatomy.  Image Markers and Patient ID Minimum of two should be imprinted on every radiograph. 1. Patient identification and date 2. Anatomic side markers  Image Markers and Patient ID – Patient ID and Date Generally include: 1. Name 2. Date 3. Case number 4. Institution Photoflashed on a special place on the cassette. Care must be taken not to obscure important anatomical part: – Chest: top margin – Abdomen: lower margin  Image Markers and Patient ID – Anatomic Side Marker Radiopaque letters R or L Preferably placed on the IR inside the lateral portion of the collimated border of the side being identified with the placement such that the marker will not superimposed over essential anatomy  Positioning Methods and Steps - Positioning Sequence and Routine Step 1. general patient – positioning Assist the patient onto the x-ray table – Assist the patient into one of the following positions: supine, prone, lateral, or oblique. – Place the cassette in the Bucky tray or on the table  Positioning Methods and Steps - Positioning Sequence and Routine Step 2. measuring part – The body part being radiographed is measure. thickness – Set the correct exposure factors on the control panel.  Positioning Methods and Steps - Positioning Sequence and Routine Step 3. part positioning – Turn and move the patient as needed to center the body part to the central ray (CR)  Positioning Methods and Steps - Positioning Sequence and Routine Step 4. Image Receptor (IR) centering – For table Bucky procedures this centering is done by moving the IR in the Bucky tray longitudinally to center the IR to the projected center light of the CR  Positioning Methods and Steps - Positioning Sequence and Routine Step 5. finishing – Adjust collimator light boarders – Place R or L markers – Place gonadal shield  Essential Projection Routine (basic) projections: Those projections commonly taken on all average patients who can cooperate fully Special (alternate) projections Those projections most commonly taken to better demonstrate specific anatomic part or certain pathologic conditions or those that may be necessary for patients who cannot cooperate fully  Topographic Positioning Landmarks Palpation: – The process of applying light pressure with fingertips directly to locate these positioning landmarks – Must be done gently: painful or sensitive area – Inform the patient about the purpose of palpation and take his/her permission – Palpation of certain landmarks, such as the ischial tuberosity and/or symphysis pubis, may be embarrassing for the patient, and you should use other related marks. The End