A friend is a neurosurgeon and they use some special saw that stops as soon as there's no hard tissue providing resistance. So you press it hard into the skull, and when it's done chewing through the bone, it immediately stops.
Apparently the scariest bit for the junior doctors to learn to use, somehow.
Same or very similar stuff is used to cut plaster casts for broken bones. You see that small circle rotating next to your veins in legs and there is suddenly some tension in the room. Especially when saw seems to keep stopping when cutting through plaster for no good reason, causing some confusion for the doctor and making him lean more heavily into it.
Afterwards they realize that harder resin casing was layered with soft fabric by previous orthopedic surgeon in previous hospital, so the thing actually worked as intended (but if you keep pressing power button and leaning into it it will keep cutting). Talking about hospital equipment in Switzerland, 2 weeks ago after a nasty paraglider crash landing.
edit: though actually I googled the skull saws which I wasn't familiar with and they might work on a similar principle, found someone talking about using them in autopsies anyway.
That's strange. Cast saws don't need to stop like that; they can't cut skin even running at full speed. Your grey matter is not as tough as your skin and you wouldn't want to touch it with even a gentle power tool, though, so it makes sense that brain-surgery saws would be different.
I'm forever grateful to the doc who actually pressed the running sawblade into his hand to prove that it's harmless, instead of just saying "don't worry, it's safe" while going to town on my leg with a power tool.
As long as the blade is suitable for cutting bone and it's all sterilized, what would make it medical grade over carpenter grade?
My Dad was the manager of a tool store for decades. He has had a lot of knee problems and he has a funny story about his knee surgeon coming into the store looking for a drill bit to drill out a stripped screw. He jokingly asked if the stripped screw was in someone's knee, and sure enough it was.
My woodworking equipment has a certain amount of jitter and give. It seems to have precision to about 1-1.5mm. I imagine medical grade machine cutting would have higher precision?
Probably, but when you're watching these surgeries as a layman for the first time it's surprising how much fumbling around they seem to do. I have a few pieces of metal inside me so took more of an interest at some point, and even those surgeons admit their job is mostly carpentry on hard mode.
A friend of mine got a hip replacement, and asked for the old hip.
They refused to give it to him. They said it was "medical waste," and they weren't allowed to deal with it, except in whatever federal manner was required.
It would need to be survive an autoclave, for one thing. It would need to be possible to actually clean it, not shed bits of paint and plastic into the patient's skull, material compatibility with antiseptics, etc.
If I thought about it for a few minutes, I'm sure I could create a long list of requirements for a suitable saw.
A counterpoint on focused ultrasound for essential tremor - just because you don’t penetrate the brain with a physical object doesn’t mean you don’t have side effects - as usual, benefits come with risks
> Tremor significantly improved in all patients. Seven experienced mild adverse effects, including 2 with transient gait impairment and a fall, 1 with dysarthria and dysphagia, and 1 with mild dysphagia persisting at 3 months.
> The key is knowing exactly where to aim. While the MRI machine took readings, Elias ran a test at a low intensity to see if he could gently heat up the spot on Doby’s thalamus he was targeting. Satisfied with the result, he then proceeded to blast an area millimeters wide with 6,000 joules of focused sound energy for a few seconds. A graph on his monitor showed the temperature jumping to about 60C (140F). Everything around it stayed at a normal 37C. Other than a brief sensation of heat inside his head, Doby said he didn’t feel a thing. Elias repeated the process three more times, checking the tremor after each. By the fourth, it was gone.
Leaving it at "knowing where to aim" is severely underselling the problem, because then the next step is how to aim.
Back in 2003 when I still studied physics I attended a talk back by a Dutch biomedical researcher who worked on shock wave lithotripsy - a procedure where ultrasound is used to break kidney stones. So same idea as this, except kidney stone
So what he pointed out was that the human body is not a medium of uniform density, so the way the sound waves propagate is hard to calculate.
Worse, the human body tends to move, even when the patient is under anesthetics. Even if you sedate someone enough to lie perfectly still, the heartbeat means blood vessels grow and shrink, breathing causes miniscule motions that can throw off the ultrasound beams.
Maybe this is specific to kidney stones though, maybe kidneys are just a lot more "floppy" organs and maybe kidney stones move a lot. Maybe the brain is a lot more "stable" in the skull. And I suppose the method of destruction is different (kidney stones need to be shattered by ultrasound waves, whereas this method uses heat), so that might also be an influence.
I'm not being critical of this technology btw, just trying to point out that the engineering problems involved are likely a lot more interesting than that this article is suggesting.
I was not aware of respiratory gating being used in SWL. So, I did a brief search and saw that the efficacy of gating had definitely changed over the years:
Interesting. Maybe part of the solution is better predicting and controlling the motion inside the human body. I could imagine using a method to guarantee a particular organ be at a certain place at a certain moment: perhaps by accelerating the body a certain way to shove the organ into a position for a moment. Or maybe by injecting microscopic machines to surround and hold an area still. Someone will figure it out.
I once had to have a Heart MRI, which was fascinating because movement normally messes up an MRI. For the heart, they attach a pulse monitor and the MRI machine pauses its movement for a split second each time the heart beats.
I'm a bit confused on the use of word non-invasive in this context.
I was under the impression that non-invasive meant no cutting of tissue. Even if ultrasound separated the cancerous tissue from the healthy tissue - how would the surgeons get it out of the head without cutting into the skull? I also thought some surgeons used diluted hydrogen peroxide irrigation for removing potential neoplastic cancerous tissues post excision?
I guess they're referring to the brain (and, by extension, the eyes!) being an "immunoprivileged zone" [1]... the brain-blood-barrier makes a lot of "everyday" stuff for the rest of the body pretty complex affairs for everything CNS related.
Anything immunotherapy in cancer treatment is extremely targeted. Early trials with new drugs include people getting cooked to death as the immune system and in particular the wrong interleukins get over-stimulated. 'Bolstering of the immune system' sounds good, but in general the immune system is a fine balance between doing the job against pathogen/cancer but not well that it is erring on being nonspecific and attacking self, i.e. autoimmunity. Unless otherwise noted, non-specific 'bolstering' in a tissue like the brain is likely not a good thing.
I wouldn't call radiation non invasive, it ages the surrounding brain tissue a lot.
For people with faster growing tumors like GBM the tumor will usually kill them before the side effects of radiation hit.
But for people with slower growing tumors like oligodendroglioma, the side effects of radiation can force them to quit their job and go on disability, years before they actually die of the cancer.
The better we get at treating these tumors and extending patients' lives, the more important it will be to avoid radiation as long as possible to ensure that extra quantity of life also has quality.
In medicine/surgery, 'invasive' is a bit of a term of art, meaning that implements physically enter the body. 'keyhole surgery' (a small incision with a scope and tiny tooling pushed through) for example is often described as 'minimally invasive'.
Yes. Even placing stents during cardiac catheterization (PCIs or angioplasty) is 'minimally invasive' because typically access is achieved by the femoral artery and snaked up (the femoral comes "direct" from the heart, for all intents).
Yes, you blow up vessels with a balloon and leave a metal sheath in them, but as you say, minimally invasive, because you didn't crack the chest to do it.
> The better we get at treating these tumors and extending patients' lives, the more important it will be to avoid radiation as long as possible to ensure that extra quantity of life also has quality.
Radiosurgery has it's limits and also horrible side effects esp in CNS tumors. If the tumor can be accessed without damaging too much healthy tissue and it's a histological type that has clean borders you are probably better off cutting it out.
Terrible analogy. I’m not sure if this is troll bait.
A better analogy would be:
> Brain tumors are like dumping a whole load of construction equipment, controlled by insatiable and sleepless toddlers that steal your food, on your property.
Cancer acts the way it does because it the cells that drive it are intrinsically out of control. “Reprogramming” those cells to “follow simple rules” would just make them… normal cells.
Edit:
Assuming your comment was made in good faith, you will likely be interested to learn about ongoing stem cell and organoid research. The first part of this recent lecture by Michael Levin may pique your curiosity [0].
Speaking for myself, the only "superpower" I got from a tumour near my brain was not being able to fully rotate one of my eyes because of pressure on the nerve that moved it. While this was a fun party trick that caused my brother to laugh uncontrollably and brought much joy to the neurology ward, I'm glad I got it removed.
I will also note that the tumour, being a tumour, had blood flow that was seriously messed up. The thing was mostly dead when the surgeon removed it, as it had suffered something like a tiny localised stroke. The idea that it was going to contribute anything sounds like bullshit.
Yeah, a whole load of construction equipment, in your living room. Which keeps multiplying by itself, and gonna take up so much space that it squeezes you to death against the living room wall.
You speak with such conviction, how much have you studied 'The Big C' or was that more of some sort of gut feeling?
I think the main simple rule they (the cancerous cells that make up a tumour) need to follow is to fecking die!
It's like they (the cells) refuse to accept it is their time. Apoptosis signals get ignored, and they just won't go quietly.(a bit like Jo Biden).
It's a bit like when you are developing in the womb, at the early stages when the embryo (the blastocyst) starts to take on human characteristics.. i.e. when the fingers of the hand develop.. if the cells between the fingers didn't follow the rules and die off when it was their time the individual fingers of the hand wouldn't develop. Indeed, we would just end up like a big fat rotund amorphous blob (a bit like Trump).
It's like the cancer cells have gone bat-shit psychotic and refuse to die quietly.. Have holed themselves up in a discarded/boarded up bando house somewhere with some machine guns and ammo.. Perhaps a few hand grenades, and refuse to go down without a fight. "I'm high strung, click I'm sprung..." ♪ ♫ ♬ ♭ And once the bando hijaks a water supply/electric, you're in for one hell of a ride (i.e. gets a blood supply from nearby blood vessel) ..
Best not to let crazy/ psychotic people get in the house in the first place..
I sometimes joke, "what about the cancer?" And not just in jest for despicable people afflicted. These are weird evolutions of ourselves. We should study them. The shit probably isn't going to be as cool as Butcher from The Boys, but ALL the removed masses of human brain tissue should definitely be preserved in a non-destructive way as possible and should be studied. I don't think we can fully understand brain abnormalities before we understand the brain, but seeing some failure cases has to help.
So we should remove them especially as we lack the full understanding to know if they are always dangerous.
Well I live in a different country and I think a panel of experts including a pathologist and a neurologist should study it. I thought it was a good idea, sorry I suck.
>You don’t want to mess with the brain if it isn’t absolutely necessary.
Who said it shouldn't be absolutely necessary? This is kinda of part of the discussion. The person in the article had a growth removed and it was benign, we didn't have enough knowledge beforehand to make that decision and the risk was deemed sufficient. Was one seizure really enough reason to remove a benign growth?
If we completely understood biology, we wouldn’t need to wait for a tumour to come along in order to take advantage of that knowledge. A tumour would still be a nuisance, they don’t bring along any more resources. OP is talking nonsense.
