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Adam’s Song September 19, 2008 2:56 pm

Aside from the poor Blink-182 reference in the title, I’ll be addressing the question Adam posed on an earlier posting.

yo science bitches! explain to me the following things, comparing and contrasting as you go:

1) CAT scan
2) MRI
3) Ultrasound
4) X-ray
5) Pete Wentz
6) Justin Timberlake

Now, the first few things are all nicely interrelated: The CAT (now more commonly known as a CT) scan is computed tomography (axial is the missing “A” word in the old name) and uses X-rays send at differing angles to create a three-dimensional picture of the scanned object. X-rays alone are useful as a radiography tool. They are an ionizing radiation that can be deflected by dense objects, which is why they are useful for imaging bones. Soft tissues provide little disruption and is usually “invisible” compared to the bones.

MRI (magnetic resonance imaging) uses nuclear magnetic resonance of hydrogen atoms (in most cases) to create a three dimensional picture of a scanned object using a strong magnetic field. It’s more effective at soft tissue scanning than a CT scan and lacks the ionizing radiation as well.

Ultrasound (ultrasonography) uses high frequency sound (2,000-18,000 Hertz) to penetrate into the body and produce an image. There’s a tradeoff between the frequency and resolution. High frequency produces a better resolution but penetrates shallowly into the body. Sonography is useful for soft tissues, looking at lesions (cysts, cancers), and is the common form of imaging for a developing fetus. The technology itself uses, what is essentially echo location. A computer measures the time and intensity of sound echoing off tissues and translates it into an image.

Pete Wentz is a member of the band Fall Out Boy and has little to do with diagnostic imaging. He produces neither a magnetic field (of any useful level) nor ionizing radiation. The band will produce high-frequency sound but the lack of focus and receiving equipment makes FOB a poor choice for sonography.

Justin Timberlake is an unexplanable phenomena.