1. Radiology & Diagnostic Imaging
Chapter 48
Radiology & Diagnostic Imaging

3. Learning Objectives Define and use the terms in the glossary
List the four views for chest X-ray, describing patient positioning for each
Discuss patient positioning for back, neck, and extremity X-ray and how to comfort the patient in pain

4. Learning Objectives
Explain the patient preparation necessary for mammography
Explain the difference between film-screen radiography and fluoroscopy
Explain the function of contrast media and special considerations of their use with patients
Describe how ultrasound waves create images of soft tissue and internal organs

5. Radiography and the Medical Assistant
Radiography—diagnostic technique using radiation to produce image of body
Radiology—branch of medicine using radioactive substances for diagnosing and treatment
Radiograph—image produced by radiation

6. Radiography and the Medical Assistant
Provider explains images to patient
Medical assistant does not interpret images
Medical assistant can explain procedures to patient regarding terminology
X-ray positioning, preparation for the test, follow-up care

7. X ray Discovered by Roentgen in 1895
Light wave causes ionization creating electromagnetic radiation
Ionization causes fluorescence of certain substances

8. X ray X-ray film blackens on exposure to light
Radiopaque— impenetrable by electromagnetic radiation
Radiolucent—penetrable by electromagnetic radiation

9. X-ray Film Manufactured to be sensitive to energy from X-ray machine
Coated with photosensitive fluid on both sides
Stored in clean, cool, dry area
Film has expiration date, store with expiration date visible

10. X-ray Views
Views are named for direction of beam in relation to body part that beam passes through
Five major views
Posteroanterior, anteroposterior, right lateral, left lateral, oblique

11. X-ray Views
Patient’s back toward X-ray tube on machine produces posteroanterior (PA) chest film
Extremities have same terminology
(A) posteroanterior

12. X-ray Views
(B) anteroposterior
(C) right lateral

13. X-ray Views
(D) left lateral
(E) oblique

14. Patient Preparation Medical assistant explains procedure to patient
Asks patient if pregnant
Instructs patient to remove all jewelry
Positions patient appropriately
Four major areas to X-ray are chest, lower back, cervical spine, and extremities

15. Chest X-ray Patient stands or lays down Patient remains still
Patient takes in deep breath and holds until directed to release

16. Lower Back and Cervical Spine X-ray
Patient stands or lays down
Patient remains still
No need to take a deep breath
Cervical spine
Patient stands
X-ray tube at patient’s head and neck level
Open or closed mouth X-ray as ordered

17. Extremity X-ray Patient sits or lies on X-ray table
Place film under affected body part
Drape with lead apron

18. Extremity X-ray

19. Mammography X-ray of breast First at age 40
Patient faces mammogram machine
Breast placed on flat plate
Machine applies pressure

20. Patient Preparation for Mammography
Give patient written and verbal instructions
Patient should avoid caffeine several days prior to test
Do not schedule close to patient’s menstrual cycle
Patient should refrain from using lotions, powders, and deodorants the day of the test
Patient must stand for 15 minutes for test
Explain that there may be some discomfort
Patient’s clothing from the waist up will be removed

21. Fluoroscopy X-ray producing moving picture
Requires contrast medium administered orally, by injection, or by enema

22. Fluoroscopy

23. Patient Preparation
Specific preparation for diagnostic testing with contrast medium
Instructions given in writing
Some require prescription for pretest medication
Discuss possibility of allergies to iodine and shellfish
Alternative testing may be indicated

24. Computer Imaging Also called digital radiographic imaging
Uses alternative to X-ray film
Provides clearer, error-free images
Computer creates image while patient is having test
Tests include ultrasound, magnetic resonance imaging, computed tomography, nuclear medicine

25. Ultrasound
High-frequency sound waves create image of soft tissue and internal organs
Noninvasive procedure
Safe to view fetus
Transducer passes over skin with conducting gel

26. Patient Preparation
Abdominal ultrasound—view liver, gallbladder, kidneys, pancreas, spleen, aorta
NPO midnight day before test
Pelvic ultrasound—view various structures in pelvis
Done transvaginally or transrectally
Patient’s bladder must be full

27. Patient Preparation Fetal ultrasound—view developing fetus
Determine gestational age, sex of fetus, measure head circumference, assess position of placenta
Patient in early-stage pregnancy should have a full bladder
Patient in later-stage pregnancy does not need to have a full bladder

28. Magnetic Resonance Imaging
Magnetic resonance imaging (MRI)
Strong magnetic field and radio waves are used to view anatomical structures
Creates three-dimensional image
Shows blood clots, nerve damage, torn ligaments and tendons, other soft tissue abnormalities
Noninvasive

29. Patient Preparation No dietary restrictions for MRI
Patient can continue medications
Ask patients about medical devices with metal in their bodies; pacemaker, surgical rods or pins, dental bridges
Determine if patient’s occupation involves small particles of metal—may require orbit X-rays prior to proceeding with MRI
Inquire if patient is pregnant or claustrophobic
Can patient lie still for at least 30 minutes

30. MRI Scanners Patient must lie on back for at least 30 minutes
Patient may use earplugs
Open or closed MRI

31. MRI Scanners

32. Computed Tomography
Computed tomography (CT) or computerized axial tomography (CAT)
Uses X-rays to produce cross-sectional views
Uses two-dimensional images to create three-dimensional image that can rotate in many directions

33. CT Scan May involve use of contrast medium introduced through IV
Technologist follows path of dye on the scan

34. Nuclear Medicine
Techniques that use radioactive material for diagnosis and treatment
Radiation therapy used to treat cancer
Positron emission tomography (PET) scanning technique used for diagnosis

35. Radiation Therapy
Delivers specific dose of radiation to specific area of body to destroy cancer cells
External radiation therapy—dose is delivered a specific distance from tumor, given over a period of weeks or months
Internal radiation therapy—implanted containers of radioactive material near tumor, or oral radioactive substances

36. Patient Preparation Patients may experience adverse effects
Provide strategies for reducing symptoms
Encourage patient to eat cool, soft foods in small portions
Encourage patient to eat on days he or she does not receive radiation
Encourage patient to plan time for sleeping and relaxing after treatment
Advise patient to arrange transportation to and from treatment

37. Positron Emission Tomography
Uses tracer (radioactive isotope that identifies cancer cells and follows their course in the body)
Tracer is injected into vein
Scanner converts signal into an image
Images are in color and the degree of metabolism or blood flow in indicated

38. Patient Preparation Patient must fast for 6 hours before PET scan
Patient is seated in reclining chair to receive IV injection
After 45 minutes, the patient lies on the scanner table for up to 2 hours
The body excretes the medication in a few days

39. Radiation Safety
Follow safety procedures to prevent exposure to radiation
Dosimeter (film badge) measures quantity of radiation
Dosimeters are evaluated

40. Scheduling Diagnostic Imaging Procedures
Pretest instructions are important
Medical assistant should explain instructions and answer questions
Give written instructions with appointment card, date and time of test, and directions to hospital or imaging center
Call to remind patient of appointment 24 hours prior to scheduled procedure

41. Discussion
Explain differences between ultrasound, MRI, CT, X-ray, and PET
Demonstrate X-ray positioning and have classmates identify position
List preparation for mammography
Define contrast medium and identify tests that use it

42. Credits