Medical Imaging

Radiography

(X-Rays)

• Uses ionizing radiation
• How does it work?
  • X-ray beam passed through the body
  • Portion of the beam is scattered or absorbed by bones, organs, etc.
  • Remaining pattern is transmitted to a detector for further processing as a picture
• Useful for detecting bone problems, infection, and tumors

Computed Tomography Scan

(CT Scan)

• More powerful ionizing radiation than X-ray
• Takes a 360-degree image of internal organs, spine, and vertebrae
  • Gives pictures in cross-sections
  • More detailed look at organs, soft tissue, blood vessels
• Better diagnostic for cancer, heart disease, infection
• More expensive than X-ray

Magnetic Resonance Imaging

(MRI)

• Uses a magnetic field and pulses of radio wave energy to make pictures
• Used to detect tumors, bleeding, injury, blood vessel disease, or infection
  • The best tool to detect a stroke
• Most expensive imaging study
• Must remove all metal prior to exam

Ultrasound Scan

• Uses high frequency sound waves to create images from inside the body
  • Sound waves travel through soft tissue and fluids but bounce off of denser tissue
  • The returning sound waves (echo) are measured and used to produce a picture
• Does not use radiation--preferred method for pregnant women
• Often used for imaging internal organs found in the abdomen (ex. gallbladder, liver)
• Used to see babies in utero