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Algorithm Brings Speedier, Safer CT Scans

Soulskill posted more than 2 years ago | from the it's-never-lupus dept.

Graphics 58

kenekaplan writes "Standard CT scanners can generate images of patient's body in less than five minutes today, but the radiation dose can be equal to about 70 chest X-rays. Lower-powered CT scans can be used in non-emergency situations, but it can take more than four days to produce those images. Intel and GE created an algorithm that speeds up a computer's ability to process the low radiation dose scans by 100x, from 100 hours per image to one hour."

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Suck my Asperger's cock (-1)

Anonymous Coward | more than 2 years ago | (#39330849)

Slashdot may have banned my main IP and account but the trolling contiunues. Now stretch your ass goatse wide and stuff a pabst blue ribbon can up it you fucking hipsters.

Re:Suck my Asperger's cock (-1)

Anonymous Coward | more than 2 years ago | (#39331223)

Yeah, preach it brother! Stick it to the MAN! We all know slashdot is run by the big MSM and TPTB who seek to control every thread running on the big cpu known as REALITY. But that's a bunch o' BS blistering smack-gobbly pie put out by the **TRUE** dark masters of slashdot. Nintendo!!!

Every time you play Mario Brothers your mind is subtlety being psycho-programmed to leave your basement, get a job and walk out in the SUN in search of so-called "healthy" activities. You can h8 me now - but one day you'll wake up on a beach next to a beautiful spouse, sipping an ice-cold can of Pabst blue ribbon and think... ass-burger was right.

Re:Suck my Asperger's cock (0, Offtopic)

Anonymous Coward | more than 2 years ago | (#39331709)

Thank you sir. You made my day. Keep up the good work.
PS: I just had 15 mod points, that expire today, and I spend them randomally.
Sorry for not noticing gem like your comment.

Keep up the good work.

God damned stupid article (5, Informative)

ColdWetDog (752185) | more than 2 years ago | (#39330943)

1. I hate 'news articles' that are chock full of hyperbole and mis information. TFA implies that most CT scanning is done in the ER for life or death reasons which is hardly true. It oversells the current radiation dose of modern 16+ slice scanners and attempts to lower the radiation doses for all CTs.
2. Current gen CT scanners cut the dose of most tests by at least half from the second and third gen scanners. Of course, TFA doesn't mention how good the new dose regimens are in terms of decreasing dose.
3. It appears that this new tech has a significant price tag. TFA quoted 1.5 million for a 128 slice scanner with the "new algorithm". More slices = faster and more resolution, but mostly faster. The current 'top of the line' is 64 slice. "Standard" CTs are 16 slice and cost anywhere from $150 - 250K.
4. At least the GE scanners run Linux!

Re:God damned stupid article (1)

ColdWetDog (752185) | more than 2 years ago | (#39330995)

And if this linked article [royalgazette.com] doesn't remind you of a certain Monty Python sketch, then you've ceased to be, kicked the bucket and shuffled off this mortal coil.

I don't see how they did that blurb with a straight face.

Re:God damned stupid article (1)

Anonymous Coward | more than 2 years ago | (#39331089)

It was so cool back in the days to see DEC/OSF booting on an MRI tech console. Diversity of both software and hardware. SGI workstations (Indigo, perhaps, I don't remember) in another room, with funky 4Dwm windows & icons. Now almost every medical equipment I run is either Windows or Linux (like that new GE CareStation we got last week). Linux, Linux, Linux. Or Windows. Or VxWorks. This starts to get boring.

Re:God damned stupid article (3, Funny)

ColdWetDog (752185) | more than 2 years ago | (#39331131)

Better get used to it. The GE tech rep said it was going to be Linux all the way down as far as GE is concerned....

Re:God damned stupid article (1)

mcgrew (92797) | more than 2 years ago | (#39339491)

The GE tech rep said it was going to be Linux all the way down as far as GE is concerned

Maybe we should replace Tux with a new mascot, maybe this guy? [wikimedia.org]

Nah, Linux is too fast. hey, Windows doesn't have a mascot and this would fit them better. Maybe GE will reconsider their OS choice?

Re:God damned stupid article (2)

meza (414214) | more than 2 years ago | (#39331127)

Did you read another article than the one I read? This is an honest question.

1. The article in fact mention that the new technique is not applicable for life or death situation where a high radiation dose is acceptable. But rather for routine tests where it is important to limit the dose.
2. Article doesn't mention different generations of CT
3. No price is mentioned that I can see. I've search for "1.5", "million", neither words are used anyway
4. No mention of linux

Maybe the link have changed from an earlier version. The article is intel.com so I assume that it's main purpose was PR, but still I thought it was pretty ok and it was clear on the improvement that was made (computation time was reduced by a factor of 100).

Re:God damned stupid article (4, Informative)

ColdWetDog (752185) | more than 2 years ago | (#39331505)

No, I added a few things -

1. The article makes breathless claims about "emergency' CT scans and gives a decidedly FUD picture to the issue of radiation exposure via medical devices. It's there, just not as dramatically as mentioned.
2. I added the different generations of CT scanners to point out that manufacturers have been cutting down dosage systematically and significantly over the past couple of decades. Again, it's really just progress.....
3. The cost of the 128 slice "new algorithm" scanner is almost an order of magnitude more than a base gen 3 CT scan. It does things that the cheaper scanner doesn't but that's a pretty high price to pay. The info comes from a linked article in TFA (see my post below the first one).
4. This is Slashdot. I thought somebody would appreciate this bit of technical trivia. Of course, if it ran OS X or if Google developed it, the thread would get 10 times the comments this one will get.

Mostly I'm just grumping about stupid press releases. If they toned down the rhetoric and added some technical detail, it might be an interesting Slashdot post. As it is, it's just fluffy techno pony drivel.

Now, if you don't mind, it's time for my nap....

Re:God damned stupid article (0)

Anonymous Coward | more than 2 years ago | (#39331975)

Thank you for the insightful post. Its a rare gem on /. these days. The sad fact is, far, far too many /. readers honestly believe that if you can't or don't produce a link it didn't happen or doesn't exist. They oddly believe the insightful moderation means you actually read the link they posted - rather than having a depth of knowledge which exists outside of the linked information.

Honestly, consider yourself lucky. I COMMONLY see /. moderators mod down comments which should be +5 as -1 Troll simply because the information is so far beyond their knowledge base and yet their ego won't allow that someone may know more than them. As such, their only choice is to strike it down via moderation to hide their ignorant shame. /. didn't used to be like that, but sadly, most of us who actually do know what we're talking about have long since left. Hell, I have a five digit UID which I refuse to use out of protest for the stupidity which is the majority of the /. readership.

So from a /. old timer, I thank you for your post. Its BY FAR the exception rather than the rule.

Re:God damned stupid article (1)

The Grim Reefer (1162755) | more than 2 years ago | (#39331555)

4. No mention of linux

My guess is (s)he works in the medical imaging field where it's pretty common knowledge. It doesn't need to be mentioned in the article. GE scanners run Linux and ran Solaris before that.

Maybe the link have changed from an earlier version. The article is intel.com so I assume that it's main purpose was PR, but still I thought it was pretty ok and it was clear on the improvement that was made (computation time was reduced by a factor of 100).

I have a friend who works for Sapheneia [alpha-imaging.com] They have been doing this for several years now. Not only have they been able to do this for some time, but they also work with almost any vendors scanner.

Re:God damned stupid article (1)

mclaincausey (777353) | more than 2 years ago | (#39331237)

"Top of the line" is now 320 rows for Toshiba, or dual-source 128 rows for Siemens. I think there are 256 detector row scanners as well.

Re:God damned stupid article (3, Interesting)

Anastomosis (1102421) | more than 2 years ago | (#39331513)

Yes, we have a 256-slice scanner that we routinely use. It is excellent for cardiac studies, where speed of scanning is important to reduce motion artifact from cardiac motion.

Re:God damned stupid article (3, Funny)

ColdWetDog (752185) | more than 2 years ago | (#39331523)

Hopefully it will stop soon. 640 slices ought to be enough for anyone....

Re:God damned stupid article (0)

Anonymous Coward | more than 2 years ago | (#39338527)

Hopefully it will stop soon. 640 slices ought to be enough for anyone....

Actually there is ALREADY a CT-Scanner able to image 640 slices in 1 rotation. This:
http://www.toshiba-medical.eu/en/Our-Product-Range/CT/Systems/Aquilion-ONE/

Let's just say it need >2-channel SCSI RAID Array to process & stored the RAW data
alone..

Re:God damned stupid article (1)

mclaincausey (777353) | more than 2 years ago | (#39331307)

Also, "faster" has a material bearing on dosage... For example, imaging doing a vascular run-off with a four-slice scanner. The narrow detector array means the patient will be bombarded with ionizing radiation for far longer than a wider detector array (higher Z-axis efficiency with more slices). And if you're doing dynamic (4D) scans (e.g., coronary functional CT scans), then getting a whole volume in one rotation is also huge and saves on radiation.

Re:God damned stupid article (0)

Anonymous Coward | more than 2 years ago | (#39333151)

1. I hate 'news articles' that are chock full of hyperbole and mis information. TFA implies that most CT scanning is done in the ER for life or death reasons which is hardly true. It oversells the current radiation dose of modern 16+ slice scanners and attempts to lower the radiation doses for all CTs.

Well, I don't know where you get your information from, but you do seem to be spewing a fair amount of misinformation yourself....As a person who orders CTs regularly, I will tell you the vast majority of CT scans ordered are for a life-or-death decision....if it weren't, we wouldn't order the damn test. That being said, there are different levels of urgency to scans....most of mine are on the order of "minutes to an hour" being critical for the well-being of the patient e.g. evaluation of traumatic injuries, evaluation for pulmonary embolisms (PE), perforated viscous organs (ulcers, appendix, diverticulitis) . The others tend to be less urgent, but still necessary (scanning for an undrained abscess which is making the patient sick, and trust me, they will not get better without it being drained).

And a 16-slice CT scan is hardly "modern". 5 years ago, yeah it was still current....right now, most places I've worked use 64, 128 or even 256 slice scans. 16 slice is woefully behind the times and produces sub-optimal images and incidentally takes quite a bit longer to obtain the scans.

2. Current gen CT scanners cut the dose of most tests by at least half from the second and third gen scanners. Of course, TFA doesn't mention how good the new dose regimens are in terms of decreasing dose.

Reference please? The general trend is for radiation doses to go _UP_ per generation of scanners, not down based on the need to pump adequate radiation to the increased number of detectors to over come the trail-off effects of the detector placement (http://www.impactscan.org/download/msctdose.pdf)

There may be specialized algorithms used (as sited in TFA), but that kinda defeats your argument.

3. It appears that this new tech has a significant price tag. TFA quoted 1.5 million for a 128 slice scanner with the "new algorithm". More slices = faster and more resolution, but mostly faster. The current 'top of the line' is 64 slice. "Standard" CTs are 16 slice and cost anywhere from $150 - 250K.

First part....won't argue here....then again, every leap forward usually has an increase in price.

As for the second part....man you are waaaaayyy off base, as I alluded to above. Just 8 hours ago I sent no less than 8 people to a 128-slice machine. Top of the line is at least a 256-slice machine, but they are still pretty rare (haven't seen one myself). And where as I do not purchase these machine directly....I seriously doubt you could get one, even a 16-slice, for $150-250k....most of the quoted prices are in the $1M range....hell, you'd probably spend $50k on transport (shipping) of the machine to your location (and that's of a new model, forget about ripping out an old one)....and don't forget about moving it into a radiology suite....re-wiring the room, installation and calibration/certification/validation charges. The yearly maintenance package probably starts around $100k. This pricing part is speculation on my part, but partial derived from discussions from friends who are radiologists and are infinitely more knowledgeable than myself.

4. At least the GE scanners run Linux!

And that means what? I wouldn't care if it was BSD, Mach, Ultrix, IRIX, or any other Un*x variant....but now I'm just being mean.

Personally, I would love for this kind of technology to become the standard....even with the higher price tag. Those in my profession (surgery) are always having to weigh the risk versus benefit of CT scans. We order a large number of them, but that's because the consequences of us being wrong is usually significant morbidity and mortality to our patients. While the current state is not amenable to my primary role as a trauma surgeon, I would be willing to wait longer for a scan for less acute issues like appendicitis, diverticulitis or such.

The added cost, really in my eye, is a non-issue....you are talking about a one-time fixed cost (marginally above the cost of a typical machine), but will almost unmeasurable benefits for the patients in the form of reduced complications from radiation exposure (most notably cancer, but radiation enteritis, and even skin burns have been described).

As a more technical note, I do question the validity of the "single thread" argument as the way scans are processes, they are broken into discrete images and while a single image may only be run on a single processor....why couldn't multiple processors simultaneously process different image sets? As an added thought, what would be the benefits of using GPUs to do this sort of work....One description used is that the algorithm used is similar to those used in ray-tracing....but I don't know enough about the algo implementation.

Doctors know fuck-all and drug companies... (0)

Anonymous Coward | more than 2 years ago | (#39339069)

profit from making people sick and killing them. Both groups of people consist of primarily ignorant charlatans who make obscene amounts of money.

On-Topic:

TFA implies that most CT scanning is done in the ER

I've had 3 CT scans in the last 2 years. Two were head-only and were done in the ER.

One was full-body and was done in a hospital radiological department after waiting 6 weeks for the booking.

---

Off-Topic, but important:

On the side, the CT scans were done for serious reasons, but showed *nothing*.

Ultimately, I almost died. THEN (after 6 years of investigation, about 10 specialists, innumerable tests, perhaps as much as 10 years of being sick (onset was subtle and very gradual), being mentally and physically sick and unable to work and finally rapid deterioration of my health, not to mention abandonment by my top-tier insurance company (read thieves) at the first post (they exploited my illness-caused weakness to get out of our contract), it was discovered that one of the miracle pills that the quacks had put me on was poisoning me. The underlying "illness" (actually poisoning) was stopped. I now have the pleasure of probable permanent neurological and other damage, but I am no longer actively being poisoned.

The first question I asked EVERY doctor that I saw about this was : Do you think my medications could be causing this. To a man (they were all men), they all would respond within 500 milliseconds with: "NO!

Be forewarned. It took every ounce of strength and finance (preciously-short commodities in my condition) and unimaginable research on my part to force the evil ignorant lying bastards from hell to solve this. ONLY you care about your health. Doctors, drug companies and insurance companies care solely about accumulating money and don't give a flying fuck about your health.

I haven't decided yet whether I want to see doctors, major drug-company executioners (I mean, executives) or indeed major insurance company (read fraud-artist) "executives" to suffer miserably and die horrible deaths first.

Oh, and forget about "House" and "Marcus Welby". They are pure fiction. Non-fictional doctors are just in it for the money, whatever way they can get it.

Re:Doctors know fuck-all and drug companies... (0)

Anonymous Coward | more than 2 years ago | (#39339661)

Sorry to hear about your issues.

Its important to remember, Doctors kill tons of people every year with prescription drugs. Even when they are fighting to control vitamins and herbs citing the dangers of their consumption, they, themselves, kill several orders of magnitude than vitamins and herbs ever have. And at the same time, vitamin treatment was also showing good results in the treatment of cancers. Not hard to do the math and see the financial motivation. Of course, this is back when the FDA literally held people hostage at gun point so many years ago.

The fact is, most all drugs carry a risk. Any doctor who refuses to acknowledge there is some risk with most any medication should be replaced as quickly as possible.

Re:Doctors know fuck-all and drug companies... (0)

Anonymous Coward | more than 2 years ago | (#39341031)

The fact is, most all drugs carry a risk.

No-one knows that all drugs carry risks better than I (the AC you replied to). Remember that I mentioned unimaginable research (on my part). I could tell you stunning things that I learned about the risks of these wonder-drugs (and the total abdication of responsibility for harmful consequences). But that is not the point.

The point is this: NEVER assume that some highly over-paid asshole (or group of highly over-paid asshole(s)) with a medical degree has a fucking clue. They just learned to sound like they had a clue. You MUST be your own doctor/chemist. Trust no-one.

We may point and laugh at village Shaman (what's the plural, Shamen?) as they behave like clueless morons and wave dead chickens over "sick" peoples' heads. In a hundred years, people will laugh at today's medical "practitioners" in the same way (as mere irrational voodoo practitioners).

My point is that doctors might be able to spot a rash, but they know sweet fuck-all about the pills they prescribe. And the evil Dr. Mengele-inspired multi-billion dollar pill industry loves it that way.

Technology is well... Just great... (1)

FranktehReaver (2441748) | more than 2 years ago | (#39331007)

Technology has been making some huge leaps and bounds over the past few years, it is almost hard to believe a few years ago I was playing Ultima Online lol. This is huge for the medical field in treating and diagnosing people without adding another problem to the list. Keep these algorithms coming! Save mankind computers and prove those terminator movies wrong!

OpenCL || Intel add (3, Interesting)

Massacrifice (249974) | more than 2 years ago | (#39331153)

Sounds like a job for OpenCL. A GPU cluster would be much more scalable than using expensive Xeons. Which also makes this article sound like an add for Intel CPUs.

Re:OpenCL || Intel add (1)

Anonymous Coward | more than 2 years ago | (#39332099)

Minor nit: "ad" = advertisement, "add" = addition.

Re:OpenCL || Intel add (1)

ndykman (659315) | more than 2 years ago | (#39332309)

Not every problem leads itself to GPGPU solutions. I'm no expert, but looking at a paper on a similar idea for optical reconstruction, I'd bet that the creation and update of the model via analysis (comparsion between predicted and actual results) is really hard to make parallel, and that process has a lot of non-localized memory access.

I'm sure you could use GPU acceleration for the CG calculations in the reconstruction phases, but I'm not sure that's the limiting factor here.

In short, there are really good reasons to use a lot of fast CPUs, and this sounds like one of them.

Re:OpenCL || Intel add (3, Informative)

Macman408 (1308925) | more than 2 years ago | (#39333253)

I think this very much is an Intel ad. I was curious, because this sounded familiar, so I looked it up. From the press release and GE's white paper [gehealthcare.com] , it looks like their system:
Uses 25 mAs dose (75% less than standard, they say)
Is ready in an hour, 100 times faster than when they started in 2006 (so 6-10x of that speedup is Moore's Law, the other 10-16x is algorithm improvement)
Uses 28 quad-core Xeons

On the other hand, a GPU solution [physorg.com] from 2 years ago:
Gives a 2-4 mAs dose (97-99% less than standard, they say)
Is ready in 1-2 minutes, 100 times faster than contemporary CPU algorithms
Uses a single GPU

Better, faster, cheaper... Pick three.

Re:OpenCL || Intel add (0)

Anonymous Coward | more than 2 years ago | (#39334021)

Stuff like this sounds more like a job for dedicated FPGAs.
The latest FPGAs make your OpenCL cluster look like a pocket calculator.

Re:OpenCL || Intel add (1)

jpmorgan (517966) | more than 2 years ago | (#39334041)

You're right. In fact, it has already been done [acceleware.com] .

Throwing resources at the problem (1)

Anonymous Coward | more than 2 years ago | (#39331207)

How to obtain a 100x speedup: consider an architecture with 112 cores, wait for 2 CPU generations to pass, and put 3 engineers on the task for several years to parallelize the algorithm by hand. Of course, giving it to the research community would have been impossible because, you know, it may have worked faster with more general solutions.

Inquiring minds (3, Funny)

sjames (1099) | more than 2 years ago | (#39331263)

Inquiring minds want to know, since this will substantially reduce the needed resources for a scan, how much cheaper will they be?

You can stop laughing now!

Re:Inquiring minds (0)

Anonymous Coward | more than 2 years ago | (#39334023)

The cost is in the machine, usually not the electrical/cooling costs.

Re:Inquiring minds (2)

sjames (1099) | more than 2 years ago | (#39334283)

Yes, but that machine now has a higher throughput. More scans to amortize across. Time is a resource.

Looking forward to improvements (2)

djbckr (673156) | more than 2 years ago | (#39331657)

I had a CT scan two weeks ago. I didn't fully realize until after I was done about the amount of radiation I was exposed to. My arm where the IV was injected with radiation hurt like hell for about 18 hours and of course I now have a higher risk of cancer. There's enough radiation in the injection that it makes you feel like you're generating heat from the inside. It's quite a weird feeling. I guess it was needed for the procedure I had to have done, but here's hoping for improvements with lowered radiation exposure.

Re:Looking forward to improvements (1)

Anonymous Coward | more than 2 years ago | (#39331737)

From what I have read, you basically get a 1/400 chance of cancer over 10 years.
Sounds like a lot/little depending on your view. My mother had 6 CTs.

Re:Looking forward to improvements (5, Informative)

Anonymous Coward | more than 2 years ago | (#39332177)

The heat you felt is really because the iodine gets to the thyroid provoking a thermal regulation change.

Re:Looking forward to improvements (2)

Drewcool (726257) | more than 2 years ago | (#39333829)

So that's why I never noticed that side effect after my thyroid was removed.

Re:Looking forward to improvements (1)

the biologist (1659443) | more than 2 years ago | (#39332505)

They don't inject radiation into you.

Yes, I am a biologist.

Re:Looking forward to improvements (1)

Anonymous Coward | more than 2 years ago | (#39333437)

Perhaps the procedure described was a PET/CT scan. In that case, they do indeed "inject radiation into you":

PET images features CT doesn't, but CT provides much better spatial resolution, which is why it's diagnostically advantageous to have simultaneous and coregistered subject imaging. The obvious way to achieve this is to build the two scanning apparatuses into the same device to provide both spatial and temporal locality. Whereas CT imaging provides its own signal (the emitter as well as the detector), PET imaging only provides detection and thus requires an active signal, achieved in the form of emissions from a short-lived source of ionizing radiation called a tracer.

Re:Looking forward to improvements (0)

Anonymous Coward | more than 2 years ago | (#39335827)

It's not enough to burn you. I have had PET/CT (several times). Sometimes you can "see" X-Rays (angriograms during Wada tests) when various mineral compounds in your eyes light up when they are excited by the exposure. It looks like sparkly flashes and is very brief. Now, you may have had a reaction to something in the iodine tracer or the iodine itself. This can make you feel warm and lower your heart rate/blood pressure. It is similar to iodine allergy.

Re:Looking forward to improvements (0)

Anonymous Coward | more than 2 years ago | (#39332513)

That's an interesting account, but it can not be accurate for two reasons:

1. No radiation sources are injected into the body during a CT scan. The ionizing radiation necessary for the scan is emitted from an X-ray tube opposite to the X-ray detector.
You probably were injected with a contrast medium to improve imaging of vascular structures. An alternative would be that a different imaging procedure was performed in combination with a CT scan (for example a PET scan).

2. Radiation in sub-lethal doses does not cause any sort of immediate "weird feeling". Even lethal doses are typically not perceptible by the victim in any way until radiation sickness sets in - in many cases, this is the reason a lethal dose is accumulated.

Re:Looking forward to improvements (0)

Anonymous Coward | more than 2 years ago | (#39333941)

1. [...]

Indeed, PET/CT imaging is quite common. (Minor exposition in my other response.)

Radiation in sub-lethal doses does not cause any sort of immediate "weird feeling".

The firemen and especially the roof cleanup crews ("liquidators") at Chernobyl commonly described a "weird feeling", along with (and/or including?) a "metallic taste" at the scene. The radiation levels they encountered were considerable (50~70Sv/h, generally considered unsafe for human exposure of any duration-- they tried to keep exposure times to ~45 seconds) but certainly "sub-lethal" as observed by modern medicine (cf. Merck manual, etc.).

The rest is a good thing to point out in general, except for your unjustified assertions here (highlighted by my emphasis):

Even lethal doses are typically [er, "sometimes"] not perceptible by the victim in any way [er, "in a recognizable, actionable way] until radiation sickness sets in[...]

Re:Looking forward to improvements (0)

Anonymous Coward | more than 2 years ago | (#39332565)

The radiation is not in the injection, but coming from the X-Ray tube inside the scanner.
So the pain likely is more related to the needle used than to radiation.

Re:Looking forward to improvements (0)

Anonymous Coward | more than 2 years ago | (#39332591)

There is no radiation from the injection they give you, otherwise the doctors and technicians wouldn't be allowed to handle it in simple glass jars all day. You get radiation in the form of fairly intense (as human exposure goes) X-rays that are shot through your body as the ring rotates around you. The IV is iodine or some other high molar-weight compound that will create contrast (shows up darkly) on the X-Ray so the Dr can see internal bleeding, other vasculature, etc.

It makes you feel warm because it causes your thyroid to react. It can also make you feel like you need to urinate, or nauseous. I got all three when I had two emergency CTs after a bad car wreck last year. :)

Re:Looking forward to improvements (0)

Anonymous Coward | more than 2 years ago | (#39333195)

The inject contrast material into you (which is benign stuff). Radiation is from the actual scanner. Contrast is injected to reduce amount of radiation needed.

http://www.ct-scan-info.com/ctcontrast.html [ct-scan-info.com]

CT scanner is X-ray machine. It makes a lot of x-rays. That's the crux of the radiation issue. There is no other source of radiation.

Now, if you ever had a bone scan, then that's a different matter ;) Lots of radiation there. And Nuclear Resonance Imaging or MRI, well, it has no nuclear radiation at all.

Re:Looking forward to improvements (1)

HiddenCamper (811539) | more than 2 years ago | (#39333813)

First, the "radiation" didnt make the burning. If you were getting enough radiation to feel a 'burn' you would be losing your hair right now. To put the numbers in perspective, you received a maximum of 1-1.5 Rem (10-15 mSv) of radiation. The average yearly background exposure not including medical is ~320 mRem/year (3.2mSv). Including medical: ~620 mRem (6.2 mSv). For a nuclear power plant worker the maximum allowed per year is 5 Rem (50 mSv). On average nuclear power plant workers get an additional 100mRem/year (1mSv), except for outage workers who average about an extra 300 mRem/year (3mSv). People working at Fukushima after the accident were authorized to receive 25 Rem (250mSv) to protect the plant and the public. There is no statistical increase in liklihood of cancer until you pass 10 Rem (100mSv). Even using Linear No Threshold which is the most conservative accepted estimate and is used by the government for calculating deaths from radiation exposure to assign value to radiation, your increase in risk is .1% over your entire lifetime due to that procedure. Again just FYIs and facts.

Re:Looking forward to improvements (0)

Anonymous Coward | more than 2 years ago | (#39333841)

With the other commenter, unless you were receiving a Positron Emission Computed Tomography (PET) with CT or Single Photon Emission Computed Tomography (SPECT) with CT there was no "radiation" injected. It was likely iodinated contrast injected as another poster said - the feeling of heat/burning is a common sensation with the intravenous contrast.

The standard reconstruction in CT has been some variant of filtered back projection with different filters for quite a while.
The notable thing about the article is that they are finally going to release a model-based iterative reconstruction algorithm for CT. These types of algorithms, that model radiation transport (photon interactions from source through patient to detector) have been used in emission tomography for the last 10 years or so.

Re:Looking forward to improvements (1)

Libertarian001 (453712) | more than 2 years ago | (#39334259)

You seriously have no idea what the fuck you're talking about, do you. "My arm where the IV was injected with radiation..." ?! Your arm was not injected with radiation. Your arm was injected with Contrast. Were you listening to the Rad Techs at all? It went something like this "OK, I'm going to inject you with contrast now. You'll feel it spreading warmly through you. Take a deep breath...and hold it... (as the scan goes), OK, breathe."

Oh, my qualification? I work on GE Lightspeed and Toshiba Aquillion CTs for a living.

Re:Looking forward to improvements (1)

swamp_ig (466489) | more than 2 years ago | (#39334319)

A number of misunderstandings in this post and the comments:

1. The IV injection is an iodine containing contrast, it does not contain radioisotopes / radiation. Iodine is a heavy, and thus radiopaque element and is used to show blood flow in the CT scan.
2. The warmth you felt is due to a histamine and vasodilatory reaction to the IV contrast, it's got nothing to do with the thyroid. It's similar to the warming sensation you get when you have a couple of shots of alcohol and actually causes you to cool down.
3. Iodine contrast is an issue - in people with severe kidney disease it can cause kidney damage. If contrast leaks from the vein into the subcutanious tissues it can cause some locallized iritation and swelling.

danger of "model-in, model-out" (1)

peter303 (12292) | more than 2 years ago | (#39331773)

Seismology uses similar model-based reconstruction algorithms. the danger is you can force the data into something that looks a lot like the input model if you are not careful. Technically this get stuck on on a false local minimum in an optimization problem.

Anatomy (1)

DrYak (748999) | more than 2 years ago | (#39341637)

On the other hand, there's quite a lot of difference betwen a hand, a head, a foot, a chest..
If the initial model used for the reconstruction is just some generic approximative shape, it will still provide some speed up, but won't be affected that much by the actual pathology which is being imaged.

How can you tell how much dosage you will get? (0)

Anonymous Coward | more than 2 years ago | (#39332061)

If you are asked to get a CT how can you tell what generation of machine will be used and what your dosage will be?

Worthwhile Goal (2)

oldCoder (172195) | more than 2 years ago | (#39332525)

A while back I had several full-body CT scans on an emergency basis. They found what they were looking for in my liver and it was treated. But I was forbidden to have any X-Rays of any kind for two years after that. So when I came down with bronchitis and pneumonia, the doctor had to play it by ear (literally, he just listened to my chest). All is well, now. But lowering the X-Ray dosage of CT scans is very worthwhile.

Picture Kiosk (1)

patriciacurtis (920142) | more than 2 years ago | (#39333929)

Looks like there may be an answer for failing KODAK. While you wait CT Scans. Kiosks on ever high-street :)

New algorithm or hand-tuned code? (1)

LeDopore (898286) | more than 2 years ago | (#39334157)

Is it really a new algorithm, or is it just that they hand-tuned the code to run iterative reconstruction quickly? There's a world of difference. There are some great algorithms out there to speed up calculation of large images where you expect them to be compressible in some basis, but from this article it looks like they didn't invent a new fancy algorithm, they just heavily optimized an existing one. Anybody have a link to a technical paper so we can find out for sure?

Re:New algorithm or hand-tuned code? (0)

Anonymous Coward | more than 2 years ago | (#39334701)

Filtered backprojection is heavily parallelizable anyway. A CT scan essentially does what's called a Radon Transform, and reconstructing the thing is an Inverse Radon Transform. There are a number of badass algorithms for doing this, the coolest of which is the Projection Slice Theorem. The problem is that you end up with a weirdly sampled image in the Fourier domain that results in some oddball artifacts when you do the I2DFFT step. As far as new algorithms go, the most interesting thing is whats called Compressed Sensing, which seems to beat the Shannon Sampling Theorem from what I read about it a while back.

Source: I did 80% of a master's degree about this before shitting and falling backwards in it.

Re:New algorithm or hand-tuned code? (0)

Anonymous Coward | more than 2 years ago | (#39336343)

> Source: I did 80% of a master's degree about this before shitting and falling backwards in it.

Thanks for the visual! :)

Not news.... (1)

whydavid (2593831) | more than 2 years ago | (#39336211)

This is old news: http://www.genewscenter.com/Press-Releases/GE-Healthcare-Unveils-Ultra-Low-Dose-CT-Technology-with-Profound-Image-Clarity-3367.aspx [genewscenter.com] And if you read through the Intel and GE press releases, you'll find numbers all over the map as to how much this actually decreases radiation exposure. It might be a 4x reduction (GE scientist quoted in Intel article), it might be a 10x reduction (Intel article), or it might be a 100x reduction (GE article). It might just depend on the specific scan being done, but you won't find that in either article. This is quite a breakthrough and is fantastic news for anyone who needs regular scans, but it is a bit overstated (as mentioned by other commenters, CT scans had greatly improved from the doses quoted by GE/Intel as baseline figures), is nearing 2 years of availability in some areas, and is going to see slow adoption as hospitals a) aren't willing to part with the expensive, working machines they have and b) the time requirement of an hour is still significant enough to rule this out in many environments. There is still a key issue that isn't mentioned here. It might take 15 minutes to get a prepped patient in the room, to scan them, and then to do all necessary work to prepare for another patient, but it takes an hour to analyze a scan. So, we either get 4 servers to process the scans (I think Intel would like this very much) or we run under capacity or we leave a long queue of scans to be analyzed overnight and read the next day. The 1st option is expensive, the 2nd option is not going to happen if there is a living accountant in the building, and the third option would still require an extra server (assuming we do more than 24 scans each day) and is only workable if there can be a day+ delay in sending results. Perhaps some Slashdotter will make a fortune with their CT analysis "cloud." And not to sound like a party-pooper, but for customers in the U.S. GE/Intel still have no power over the insurance approval process which can delay your scan by another order of magnitude. Let's celebrate this for what it is, a nice improvement for a small niche of healthcare consumers who require several CT scans in their lifetime, and not for the miracle-machine that the GE/Intel marketing department would have us believe.

So what, exactly, have they done? (1)

ChrisMaple (607946) | more than 2 years ago | (#39338619)

Except for some vague references to parallelizing (alleged) essentially single threaded code and peephole optimization, what have they done? Where's the great advance in software that the headline promises? How are the new algorithms difference from the old ones? Where's the statement of the underlying difficulties? TFA is inexcusable puffery.
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