Randomness
I have managed to be able to drink half a cup of coffee. 5 bags of sugar, 25% milk. I also spilled some of it on my notes. Looking at my brown notes, it brings back memories of all my coffee-stained papers my teachers gave back to me.
There are two other students with me in Nuclear Medicine: Derrick and Clarisse. It felt good to not be the only oblivious person there. Derrick tells me how he wishes there were 30 hours in a day so he can study for 24 hours and sleep for the other 6. He tells me to appreciate my last few months of High School before I start college. I am starting to feel guilty for getting at least 10 hours of sleep.
Self-Research
I was able to use a meter and a cobalt source to measure the attenuation of some materials. The detector was a bit fickle and swung back and forth. I used a patient as a source because the amount of the shot was more than my cobalt source.
It was surprising to me that there is no measure thing for mitotic rate but after some thinking, I have realized that people grow at different rates so finding it would be difficult. There is a thing called mitotic index which is a percent of cells undergoing mitosis in a certain area (cm^2, inches^2, etc)(not all cells are undergoing mitosis). I will probably have to compare the mitotic index of cancer cells to normal cells and then use that to make a calculated guess at what the regular mitotic rate is.
Observations/Learning
I also got to see some DAT scans where Iodine-123 was used to check if a person has Parkinsons. If a part of the brain does not take up the Iodine-123, then the person supposedly has Parkinsons.
I was also allowed to see the injection of Technesium-99 (TcO4 which is a good leaving group (for chem kids) or is it TsO?... Dr. Duffy don't get mad at me >.< ) into a patient's liver (I was behind a lead wall). This was done in intravenous radiology, where the doctor was using real-time x-rays to move a small tube, called a catheter, through the patient's arteries. This is done manually with a device the doctor manipulates. They use a certain radiation absorbing liquid called contrast which shows the doctor where the arteries are on the x-ray.This is a preliminary test which tests for any slippage before therapy. The Technesium is placed into the the artery of the liver which will then lead to the capillary beds of the liver. Because the beads of Technesium-99 are so small, it will not leave the capillary bed. But if there is a physiological difference called shunting, which allows the slippage of the Tech out of the capillary bed, then the danger for therapy increases.
The therapy is the use of Ytttrium-90 in types of beads to kill off tumors in the liver. This is a last ditch effort to control the cancer so that the patient can get a liver transplant. If the cancer spreads out of the liver, then a liver transplant is useless and it will be canceled. Makes my SRP seem small in comparison. The reason they have to test for slippage is because if they use the Y-90,which might go to other places like the lungs and the stomach, it will kill off other tissues and may cause the death of the patient.
There is a specific type of bead used to store Y-90 called a SIR-therasphere. This attaches/attracts the platelets in the blood which will cause a clot at the tumor; a two-pronged attack which will starve it of blood and nutrients and kill it with beta-radiation. The amount of planning and precision required in such therapy is scary and personally I would be afraid of it myself.
Many of the other workers and doctors at the hospital are surprised to see a high school student in Nuclear Medicine. They spoke to me of their college experiences and what medical school/ medical career is like. I am thankful for all their advice, it provides a different perspective on the subject. It seems like most people have had more than one job/career.
Some sheets of radioactive cobalt in a lead case used for testing the machine's performance.
Thanks for reading,
-Phillip Yang
Sounds like really heavy stuff. When you say you used a patient as one of the sources for the experiment, did you just have a sample of their blood or did you actually have them in the room with you?
ReplyDeleteI had them actually in the room with me. They have to inject the radioactive tracer into the patient before the test. The time between injection and the actual scan is important because the tracer will decay. The radiologist will also want the tracer to go through the system to determine any abornormalities. Generally tracers all look the same on the detector when initially injected because it will go to the blood and heart and etc. It will take a little time before the body actually takes it to use.
DeleteWow! This was fascinating to read! On average, how long dues this procedure increase the survival time for patients with liver tumors?
ReplyDeleteNot quite sure, but I read somewhere that you want to put it in if you think the patient will not last for more than 3 months. I would assume that the patient will be somewhere near the top of the donor list if they are almost about to die. It really depends on the amount of tumors in the liver and how fast the tumors are killed by beta-radiation. If the tumors are somewhat eliminated (very unlikely to get rid of 100%), then it might prolong the patient for a couple of months. There will always be some form of slippage in the insertion of the theraspheres, so it is a battle against how fast the tumor kills the patient or the therasphere. In the unlikely occurance, the Yttrium-90 might decay into some dangerous daughter isotope and the patient might be killed.
DeleteAsked again, and it turns out the patient will last 5 years or less. The problem is that liver cancer usually arises from more than one factor such as Cirrhosis and Hepatitis C.
DeletePhillip! Your project is seriously so cool. I always picture that you are in some underground lab in a high tech basement or something (your references to lead walls and such). Wow, the people you are with sound intense. Totally understand what you mean by feeling like you're oblivious (I am by far the least knowledgeable person in my office, it takes some getting used to!). Do you have to wear any specific equipment to protect yourself? Nuclear medicine sounds really cool but also kind of dangerous!
ReplyDeleteThanks Charlotte! It isn't underground really but we do have some that are. All of the walls and glass in Nuc Med are made of lead so in truth I am in a lead department. I am actually not receiving too much radiation. In theory I am receiving less radiation than I if I had to take a CT-scan. There are alarms and warning signs everywhere but that is mostly because of regulation and rules. I do have a ring and badge that measures my monthly exposure to radiation. I will post that sometime when I have to turn them in.
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