1. AHM 244 Introduction to Imaging

2. Principles of Radiology
X-rays (discovered late 19th century)
Computed Tomography (CT scan)
Sonography (ultrasound)
Fluoroscopy
Nuclear Medicine – used for diagnostic and therapeutic procedures
Magnetic Resonance Imaging (MRI)
Positron Emission Tomography (PET)

3. X-rays Radiography High energy waves that cannot be seen or felt
Similar to photographs
Radiopaque – do not permit passage of x-rays i.e. bones; show up on x-ray
Radiolucent – permit the passage of x-rays i.e. soft tissue; do not show up on x-ray

4. X-rays Patient Positioning 2-dimensional
Requires 2 exposures 90 degrees to each other
May require multiple positions and views
Review standard positions in handouts and in text
Review exam sequencing in text
Radiation Safety
Can cause cellular or genetic damage
Minimize exposure
Avoid unnecessary exams
Limit area of body exposed
Shield sensitive body parts
Pregnancy status
Workers:
Use shielding
Wear dosimeter

5. Diagnostic Procedures
Mammography –
x-ray examination of the breast
Vital adjunct to biopsy
Performed yearly after age 40 or sooner with history or suspicion

6. Diagnostics cont… Contrast Studies Used to differentiate structures
Introduced via IV, catheter, orally
Iodine – blood vessels; if allergic to shellfish, do not use iodine!
Barium – intestines and stomach
Air - Joints

7. Fluoroscopy Use of x-rays to observe movement within body
Contrast mediums used such as barium or iodine
Blood flow, beating heart, digestive tract
Also used to aid in reducing fractures or implanting devices such as pacemakers, stents, etc..

8. Computed Tomography
Cross-sectional group of x-rays that target a specific site
Tube circles the patient, computer analyzes to create the cross-sectional views
Done with and without contrast
Organs can be viewed from all angles

9. CT Cont….

10. Sonography Ultrasound Non-invasive Uses high-frequency sound waves
Creates cross-sectional still views or views in real time movement with help of a computer
Used for heart function, abdominal and pelvic structure views and fetal visualization

11. Sonography cont…

12. MRI Magnetic Resonance Imaging
Uses high-intensity magnetic fields (magnets), radio waves and computer analysis to create cross-sectional images
Used for central nervous system studies, joint structure, etc.
Done with or without contrast
Claustrophobia is an issue
Metal implants from surgeries is a contraindication
Patient must remove any jewelry and other metal objects

13. MRI cont…

14. Nuclear Medicine
Small amounts of radionuclides (radioactive materials) are injected
These concentrate in specific areas of body
Computer cameras detect particles and create an image
Used to study thyroid, brain, lungs, liver, spleen, kidney, bone and breast
Positron Emission Tomography (PET)
Single Photon Emission Computed Tomography (SPECT)
Assists with diagnosis of cellular abnormalities esp. cancer

15. Nuclear Medicine cont…

16. Interventional Radiologic Procedures
Designed to treat specific disease conditions – helps patients avoid surgeries, life-saving
Percutaneous Transluminal Coronary Angioplasty (PTCA) – balloon angioplasty; used to enlarge lumen of blocked artery
Laser Angioplasties – use lasers to remove deposits in vessels
Vascular Stents – plastic or wire tubes inserted into a constricted vessel to open it; this procedure is guided by fluoroscopy
Embolizations – artificially stop bleeding from a blood vessel or reduce blood flow to a diseased area of an organ

17. PTCA

18. Laser Angioplasty

19. Vascular Stent

20. Embolization

21. Radiation Therapy Major force in fight against cancer
Uses high-energy radiation to kill cancer cells
Used in conjunction with surgery and chemotherapy (drug therapy)
Precise and carefully planned by radiation oncologist (MD specializing in radiology)
Each treatment must be identical to a specifically defined area of the body
Side effects: weight loss, hair loss, loss of appetite, skin changes, digestive system disturbances

22. Patient Education & Preparation
Help alleviate anxiety
Calm fears
Explain procedures
Explain preparation – different for each test from no prep to liquid diet and laxatives
Assist as needed
Post procedure education

23. Handling and Storage of Radiographic Films
Protect unexposed films from extremes of temperature and light
Exposed films kept in protective sleeves
Maintain patient confidentiality per HIPAA
Correct labeling of patient films
Films obtained on site remain part of patient record – films belong to the site that performed the procedure; can be signed out by patient or sent by courier to specialist or PCP
Digital films can be kept in the EMR
Written summary sent to providers of patient care
Teleradiology – computed imaging and information systems; many places use (PACS) Picture Archiving and Communication System to store films on computers
Can outsource films this way to other countries even for a radiologist to read films; consults with specialists from around the world is possible with this system and in rural areas