Examples of how Isotopes are used in the medical field today..?

Question

Dont have to give lots of details if you don't want to. Please just dont give me a link to google or something though. Thank you.

Answer 1

There is an entire field called "nuclear medicine" which involves the introduction of radioactive tracers into a patient which are then selectively concentrated in areas of the body that are subsequently imaged using something called a gamma camera. Here are a few specific examples of nuclear medicine studies that I order in my practice as a surgeon:

1) HIDA scan, with CCK ejection fraction: this involves a radiolabeled compound introduced into the bloodstream which is removed by the liver and then excreted in the bile. Once it is concentrated in the bile, we can take pictures of the liver, gallbladder and bile duct system with a gamma camera.

2) Gastric emptying study: using radiolabled liquid and solid food, this shows whether the stomach preferentially retains one or the other, and if the amount of time food spends in the stomach is abnormally long.

3) Thyroid scintiscan: using the fact that normal thyroid tissue concentrates iodine, we can give a radioactive iodine isotope I-123, and then "watch" the thyroid with a gamma camera. Nodules of increased or decreased uptake within the thyroid can be visualized. Areas of decreased uptake that correspond to lumps that we can feel are concerning for cancer.

4) Sestamibi scan: uses an isotope labelled compound which is preferentially taken up by the parathyroid glands. These live behind and to the side of the thyroid gland (in the neck) and can be very difficult to find. When they need to be evaluated surgically, this is a helpful tool.

5) Stress thallium test: the isotope is taken up by the heart muscle and images are obtained with the gamma camera in multiple planes. The resulting image looks like a cup, the shape of the muscle around the left ventricle of the heart (the one that does the majority of the muscular work). Areas of old infarct (old heart attacks) appear as defects in the walls of this cup because those regions are where muscle has been replaced by scar which is not active. Next, a medicine is given which tends to simulate cardiac stress and limits blood flow. If any new areas appear to lose radio isotope, then these regions are termed "reversible ischemia" and are at risk for heart attack if stress were to occur.

6) V-Q scan: this is a now outdated study that was aimed at trying to find regions of the lung that may have had a large blood clot (pulmonary embolus). It's now replaced with a "spiral CT scan", but it's still around just in case there might be a reason that CT isn't the right choice.

7) Lymphoscintigraphy and sentinel node biopsy: I saved the best for last! It used to be the standard in all cases of breast cancer, that in addition to removing the cancerous breast, the armpit on that side would also be entered and a large block of fatty tissue containing lymph nodes would be removed as well. The pathologist would search through those lymph nodes and look to see if any of them had cancer inside. It turns out that we only need to send one or a small number of lymph nodes to the pathologist in order to have a very effective detection tool. We just hve to choose that node carefully. The method is called sentinel node biopsy, and it involves the injection of a radio isotope into the breast, and then using a hand held geiger counter over the armpit. The isotope flows from the breast into the armpit and is captured by the first lymph node it comes to. We then locate that lymph node with the geiger counter probe, and remove it through a very small incision. This technique is 97% as accurate as removing a big wad of tissue, and it hurts much less.

I can already think of about 3 or 4 more, but the ones above are very common and if I started to list even more, then I'd be venturing into the ones that are relatively rare - at least in terms of my practice.

Answer 2

tracking and definition ( a few details might help they are used to track blood flow during CT Scans and for definition in abdominal X-Rays ) In industry they are used as a portable self powered x-ray machine and they COULD be used this way in medicine with care but i haven't heard of it ( these are much larger and more powerful isotopes than the ones previously mentioned - of course )

Answer 3

Several uses. Positron emitters are injected into the bloodstream to generate gamma rays for positron-electron tomography. Various radioisotopes (e.g., cobalt-60) are used for zapping cancerous growths. Radioactive iodine is used to degrade thyroid activity if the thyroid is overdoing it making thyroxin.