MONITORING ORGANS

1. Ultrasounds• Use of sound above human

hearing range to image body structures, including soft tissues

• Sounds waves are reflected (echo) off of different density tissues differently

• Baby face:https://www.youtube.com/watch?v=CV-qByKpFeY

2. X-Rays

• Oldest form of imaging• Found by German physicist

Wilhelm Rontgen, 1895 • High-energy electromagnetic

waves that pass through soft tissue (ex. muscle) but are absorbed by dense tissue (ex. bone)

• Can also be used to see soft tissues with the help of stains (ex. bismuth)

Most popular use:

• Dental x-ray exposure dose seems to vary significantly…

An aside...

Electromagnetic radiation- Forms of energy, some on the visible spectrum

(light)

• Some can be damaging to our DNA, in particular high-energy high-frequency waves (above colour spectrum)

3. CAT Scans: computerized axial tomography scan

• An X-ray machine rotates around the patient taking hundreds of individual pictures form many angles

• More sensitive than an X-ray alone• Computer re-assembles the picture into a 3-D

image, allowing for organs to be viewed section-by-section

A CT or CAT scan (computed tomography) is a much more sensitive imaging technique than x-ray, allowing high definition not only of the bony structures, but of the soft tissues. Clear images of organs such as the brain, muscles, joint structures, veins and arteries, as well as anomalies like tumors and hemorrhages may be obtained with or without the injection of contrasting dye.

• Full body scans are still not routinely done due to high incidence of “incidentalomas”, not real issues that show up as issues on the scan

• Known to increase chances of cancer in children…

4. Nuclear Medicine

• Measures radiation emitted from within the body and provides information about the function of the organ, not just its structure

• Uses radioisotopes (unstable atoms) that are injected into the target organ for imaging

• Large amounts of isotopes collect at site of damage “lighting” it up

• Ex. PET scan: positron emission tomography