Magnetic resonance imaging, or MRI, is a widely used medical tool for taking pictures of the insides of our body. One way to make MRI scans easier to read is through the use of contrast agents -- magnetic dyes injected into the blood or given orally to patients that then travel to organs and tissues, making them easier to see. Recently, researchers have begun to develop next-generation contrast agents, such as magnetic nanoparticles, that can be directed specifically to sites of interest, such as tumors.
But there remains a problem with many of these agents: they are sometimes difficult to distinguish from our bodies' tissues, which give off their own MRI signals. For example, a researcher reading an MRI scan may not know with certainty if a dark patch near a tumor represents a contrast agent bound to the tumor, or is an unrelated signal from surrounding tissue.
Caltech's Mikhail Shapiro, assistant professor of chemical engineering, thinks he has a solution. He and his team are working on "erasable" contrast agents that would have the ability to blink off, on command, thereby revealing their location in the body.
"We're developing MRI contrast agents that can be erased with ultrasound, allowing you to turn them off," says Shapiro, who is also a Schlinger Scholar and Heritage Medical Research Institute Investigator. "It's the same principle behind blinking bicycle lights. Having the lights turn on and off makes them easier to see, only in our case we just blink off the contrast agent once."
The new research was published in the February 26 advanced issue of Nature Materials, and is on the cover of the May print edition out this month. The lead author is George Lu, a postdoctoral scholar in Shapiro's lab.
(Score: 0) by Anonymous Coward on Friday April 27 2018, @11:20PM (10 children)
Wouldn't it be easier to just do an MRI, then give the current set of markers and re-MRI, and compare the two recordings? Seems like that would have the same effect. Unless this erasable stuff is intended to be a realtime change, being turned off while in the MRI machine.
(Score: 2) by RS3 on Friday April 27 2018, @11:39PM
I agree and was just going to write the same thing. The problem is cost- they'll want to bill for running the machine twice. You do understand that money is more important than health?
The same goes for CT scans- with and without contrast. Sometimes they give oral contrast stuff which makes the entire GI tract light up on CT, but it also masks other things, so getting CT both with and without contrast is best.
(Score: 1) by Ethanol-fueled on Friday April 27 2018, @11:41PM
Human lives cost money, and that would double (or even triple) the cost of just one MRI. Plus people freak the fuck out in MRIs because of the extreme scary noises they make.
(Score: 3, Insightful) by insanumingenium on Friday April 27 2018, @11:50PM (7 children)
Just a half assed guess, but I am betting getting them into a position that exactly overlaps after contrast is likely impossible. Taking the exact same picture twice is difficult, I can't imagine it is any easier in 3 dimensions.
(Score: 4, Informative) by RS3 on Saturday April 28 2018, @12:14AM (6 children)
Exact position is not necessary. Image analysis software can correlate and differentiate the images, but mostly just extremely intelligent doctors can see everything, compare scans and things, etc.
A few months ago a Dr. was reviewing CTs of a relative (of mine) with me and he just whisked through everything, pointing out every organ, any anomalies, etc. And he was a urologist; CT review is not part of his every day job. There are radiologists who specialize in reading CTs, and all other types of imaging. Most of us see lots of shadows and shades of gray blobs and these people see every subtlety with complete clarity.
(Score: 2) by Walzmyn on Saturday April 28 2018, @01:21PM (5 children)
This is my wife. She drives me nuts. "Can't you see it?"
No, I see a low resolution of the lunar surface in this one and a xenomorph in this one. These organs and tissues you're talking about, you're just making them up.
(Score: 0) by Anonymous Coward on Saturday April 28 2018, @02:01PM (1 child)
Sou ded like bs to me too:
https://www.washingtonpost.com/news/wonk/wp/2013/02/19/study-most-radiologists-dont-notice-a-gorilla-in-a-ct-scan/?noredirect=on [washingtonpost.com]
(Score: 2) by RS3 on Saturday April 28 2018, @03:07PM
That's an interesting, but somewhat flawed study IMHO. The human brain, at its most fundamental, is a pattern-matching machine. The radiologists are looking for the shapes and densities of cancer, cysts, nodules, etc. They're not looking for gorilla outlines. A proper test would be CTs of known cancerous lungs versus non-cancerous lungs.
That said, I've recently discovered that I live in an area with stellar medical providers. My sister was recently chatting with someone from another area of the country, and that person commented "you're so lucky- you have the best nurses in the nation in your area". Turns out it's doctors too. I certainly see car license plates from many other states in the hospital parking lots here, especially the specialty hospitals.
(Score: 2) by RS3 on Saturday April 28 2018, @03:10PM (2 children)
Is she a radiologist? If not, maybe should be? The various radiology (X-ray, MRI, CT, PET, ultrasound, etc.) techs do a detailed initial analysis, mark and annotate images, etc., then the radiologist (MD / DO) gets it. I think ultrasound would be a great field for anyone wanting to get into medicine but not full med. school.
(Score: 2) by Walzmyn on Saturday April 28 2018, @04:18PM (1 child)
She's a Veterinarian, which is "All of the above" in the medical world.
Her sister is a Nurse Practitioner and brother is an MD, Radiation Oncologist.
I get it from all sides.
(Score: 2) by RS3 on Saturday April 28 2018, @04:51PM
Hopefully not literally X-rays and needles!
That's awesome that you have these people, should (when) you ever need them. I deeply wish I had gone into medicine...