i absolutely love that you made this with the story of how these discoveries were made over time which i believe helps build up the understanding of what these phenomena are and how they affect the human body.
Today is Thanksgiving. One thing I am thankful for are videos like these where the hard work of others have been expertly and professionally explained. All I have to do is watch, read and learn ! Of course homework helps to remember some of it. Thank you for your great videos ! We are really blessed to live in the times we live in !
would you mind doing a similar video about radiation effects on the human body. Like how is cosmic background radiation beneficial, how exactly does cancer treatment benefit us, from current research why is too much radiation destructive and how is that limit measured, and how have the measurements for those things been developed over time?
Thank you for making these videos, best explanations and most information given in short amounts of time. Can you explain why B+ decay emits x-rays? When learning more about PET a lot of sources said that FDG produces gamma radiation.
That's true. Remember, B+ decay is basically a positively charged electron or positron. Being the antimatter equivalent of our standard electron, a positron can't exist too long in our regular matter world. When the positron runs into an electron, they immediately annihilate one another and turn into pure energy - two 511 keV gamma rays oriented 180 degrees from one another.
Actually emits gamma rays, indistinguishable from x-rays as they both have similar energies and carry no charge but the former are generated in the nucleus and the latter in the electron cloud surrounding the nucleus. B+ decay is seen in unstable atoms with excess protons. The B+ particle is a positron, the antimatter equivalent of the electron carrying the identical atomic mass with the opposite charge. Matter and antimatter don't get along well, basically annihilating one another and converting into pure energy. When the positron leaves the nucleus, it annihilates itself and the first electron it encounters in the electron cloud converting the mass of both particles into pure energy (in accordance with Einsteins famous energy/mass equation) by producing two gamma rays of 511 keV energy which travel 180 degrees away from each other. These are the rays that our scintillation cameras detect. The positron itself could never make it out of the body to be detected directly.
Great video! Thank you for making this. I just thought I should point out that the imaging modality shown at 30:24 is not a PET machine, but is instead a SPECT machine. Thanks again for the help.
Harry Marquis Hi That's mostly right but technically you can perform PET imaging on a gamma camera with the right collimators, this is rarely rare though just thought I'd mention this.
Actually, the 1st PET scanner was a Dual headed gamma camera with heavy parallel collimators withe the energy window set ~511keV and software which accepted only counts received within a small amount of time (ms) and in parallel to each other ---sometimes referred the gamma caner PET imaging
Hi Christine. It is generally accepted that the image of the hand with a ring was of Roentgen's wife, Anna Bertha and is considered by most to be the first medical radiograph. For any school test purposes, I would say that is true. It is also generally accepted that, upon seeing the ghostly image of the bones of her hands, Mrs. Roentgen declared "I have seen my death". However, the facts are the famous image was only labeled "Hand with ring" by Roentgen himself and some historians claim that Roentgen never described the image as that of his wife in either print or presentation. Many also doubt that Roentgen would have used his wife for the first radiographic image as he tested many combinations of plates and phosphorescent materials while he perfected his technique over the 7 weeks he was sequestered in his Wurzburg laboratory. If you do a google search on the first radiographic image of the hand, many different images pop up, including the probably more reliable image of Professor Albert Von Kolliker's right hand that Roentgen obtained during his presentation to the Wurzburg physico-medical society around Christmas time of 1896. Again, on a multiple choice test, I would answer that it is Roentgens wife hand but definitive proof is lacking. Hope that helps!
Mea Culpa. That should be centimeter! I don't know where that pronunciation came from but some where in my training as either an electrical engineer or medical doctor, a few of my professors used that descriptor regularly and every now and then I slip up! I'll work on it...