Even without anything fancy, is there a speed vs clarity parameter(s) when doing an MRI? It seems an easy improvement would be to spend more time getting a clear picture of the specific area of interest, vs now where the whole scan seems to be done at full clarity.
Yes, although currently scans are typically done at "full clarity" following a "standard" clinical protocol that is the same for everyone. It's generally thought that in the future the field will move towards using scans are are more tailored to each particular patient.
FastMRI leverages adversarial training to remove image artifacts
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Re: FastMRI leverages adversarial training to remove image artifacts
#22Earlier quoted context omitted.
The xerox scanners had a setting to disable compression as well. People are lazy and don't enable the compressions. Although they are highly skilled, radiologists don't have time to inspect each image, so why bother looking at the raw originals? The question is rather: does this feature improve diagnoses? Sure, the images look nicer now. But that's not why they are being created. MRI images are made for inspection by…
It gets even worse than that sometimes. For example, I remember a study from back when digital xray was getting going, where radiologist were asked to say which processing they liked better (since none of them looked quite like the very non-linear film versions) and scored on performance. They didn't perform best on the types they liked best. This wasn't a great study in terms of power, but it was interesting. I've m…
The advantages they gave were in every other way (physical storage, availability, duplication, speed at which they could be accessed etc).
Re: FastMRI leverages adversarial training to remove image artifacts
#23And this is distinctly different from compressed sensing which uses a high frequency and mathematical basis.
Re: FastMRI leverages adversarial training to remove image artifacts
#24Re: FastMRI leverages adversarial training to remove image artifacts
#25Re: FastMRI leverages adversarial training to remove image artifacts
#26Re: FastMRI leverages adversarial training to remove image artifacts
#27Facebook has absolutely no reason to be doing work with healthcare. Sure they have great computing power and top engineering talent to figure out how to sell more ads, but the trade-off for any educational facility to freely hand over medical data (de-identified or not) is wreckless.
Re: FastMRI leverages adversarial training to remove image artifacts
#28Here are the results from the paper:
The radiologists ranked our adversarial approach as better than the standard and dithering approaches with an aver- age rank of 2.83 out of a possible 3. This result is statisti- cally significantly better than either alternative with p-values 1.09 × 10−11 and 2.18 × 10−11 respectively, and the adver- sarial approach was ranked as the best or tied for best in 85.8% of 120 total evaluations (95% CI: 0.78-0.91). The dithering approach is also statistically significantly better than the standard approach. We also asked radiologists if banding was present (in any form) in the reconstructions in each case. This evaluation is highly subjective, as “banding” is hard to define in a pre- cise enough way to ensure consistency between evaluators. Considering each radiologist’s evaluation independently, on average banding is still reported to be present in 72.5% (95% CI: 0.62-0.82) of cases even with the adversarial learn- ing penalty. The radiologists were not consistent in their rankings; the overall percentages reported by the six radiol- ogists were 20%, 75%, 75%, 80%, 85%, and 100% for the adversarial reconstructions. In contrast, for the baseline and dithered reconstructions, only one radiologist reported less than 100% presence of banding for each method (80% and 85% presence respectively, from different radiologists). We believe these numbers could be improved if more tuning went into the model; however, it’s also possible that features of the sub-sampled reconstructions generally may be con- fused with banding, and so any method using sub-sampling might be considered by radiologists as having banding. Sub- sampled reconstructions generally have cleaner regional boundaries and lower noise levels than the corresponding ground-truth.
Re: FastMRI leverages adversarial training to remove image artifacts
#29Facebook has absolutely no reason to be doing work with healthcare. Sure they have great computing power and top engineering talent to figure out how to sell more ads, but the trade-off for any educational facility to freely hand over medical data (de-identified or not) is wreckless.
What exactly is the concern with de-identified medical data? This is common practice in medical research and explicitly allowed under federal law.
Re: FastMRI leverages adversarial training to remove image artifacts
#30Earlier quoted context omitted.
It gets even worse than that sometimes. For example, I remember a study from back when digital xray was getting going, where radiologist were asked to say which processing they liked better (since none of them looked quite like the very non-linear film versions) and scored on performance. They didn't perform best on the types they liked best. This wasn't a great study in terms of power, but it was interesting. I've m…
Digital and computed radiography are quite poor examples of progress though, as the resolution is worse and the radiation dose was higher than film radiography. This may have changed in the last few years but was strikingly true at the outset. The advantages they gave were in every other way (physical storage, availability, duplication, speed at which they could be accessed etc).
The issue was, radiologist had to deal with a choice of different post-processing of this data. The processing they said they liked best (somewhat consistently) was not the processing that they performed best on, empirically (somewhat consistently).
This is related to the issue of evaluating the value of ML post processing, we could see a similar effect there. After all one school of thought was that preference was in some sense driving by familiarity rather than what they were actually able to discriminate.
FWIW IQ evaluation in MRI is a somewhat problematic thing anyway, but acceleration certainly tends to make it worse in some ways. It's not obvious how effective various mitigation approaches are.