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If it can target and kill cancer, how can it also be safe for foetuses?

by verisimi 1y ago

f1shy 1y ago
You can vary the frequency, power, energy, focus... is not the SAME ultrasound.
- verisimi 1y ago
  But surely it could cause some damage at a lower frequency, power, etc anyway?
  - perilunar 1y ago
    Why “surely”? Most things that are harmless or even necessary at one level are deadly at another: heat, light, water, food, air… pretty much everything really. “Dosis sola facit venenum” (only the dose makes the poison)
    - verisimi 1y ago
      Using the example of a laser - you can have a powerful laser that can burn through metal. A far weaker laser (many magnitudes weaker) could still damage eye sight. Alternatively, water erodes mountains eventually. I don't think you can argue that ultrasound imaging is harmless or a treatment/dose. It might be that it does nothing. It might also be that it does something (like when it destroys cancer cells) only its far milder, and not an obvious observation. PS I know there are mild ultrasound devices to aid muscle recovery. These devices do something, presumably. If mild devices are acknowledged to impact muscles etc, some (mild probably) effect is occuring. Given there are occasions where these devices are known to have an impact on adults, why should we presume that there is no impact on the technology when it is looking at a developing foetus? PPS Even in studies that say there is 'no effect' from ultrasound imaging, there is a tolerance of up to 10% difference between the control and the subjects. PPPS And of course, sometimes the control is 'children who have only had 1 ultrasound' vs 'children who have 2 or more ultrasounds' - ie the control is not 'children who have who have had no ultrasounds' - ie we do not get true control studies.
  - hgomersall 1y ago
    Potentially, but these things are well controlled and understood: https://www.bmus.org/education-and-cpd/cpd-resources/top-tips/medical-ultrasound-safety/ https://www.bmus.org/education-and-cpd/cpd-resources/top-tip...
BobaFloutist 1y ago
That's like asking how if a laser can cut through steel how lamps can be safe to have indoors.
- verisimi 1y ago
  Do you have a link or something that compares the power in both? I can't find one. This is the summary I get from chatgpt - comparing Histotripsy and ultrasound imaging | Property | Strongest Diagnostic / Imaging Ultrasound | Histotripsy (Therapeutic Ultrasound | | Frequency | 2 – 10 MHz (obstetric: 2–5 MHz; high-res imaging up to 15 MHz) | 0.25 – 3 MHz (sometimes up to 6 MHz) | | Pressure (Peak Negative) | Up to ~5–6 MPa (mechanical index limit ≈ 1.9) | 10 – 100 MPa (depending on type: intrinsic vs. boiling histotripsy) | | Intensity (Spatial Peak, Temporal Average) | Typically < 0.1 W/cm²; upper safe limit ≈ 0.72 W/cm² (FDA/AIUM) | 100 – 10,000 W/cm² (very high peak intensities) | | Pulse Duration | Microseconds (∼1–5 µs typical) | Microseconds to milliseconds (short bursts for mechanical disruption) | Its kind of hard to know what this means - some of the numbers seem pretty close/crossover - but I don't think saying the difference is akin to a laser and a light.
  - an-honest-moose 1y ago
    There are 2 to 5 orders of magnitude difference in intensity. That alone is a pretty big difference.
    - verisimi 1y ago
      It's a big difference, but it is not obvious to me that there can be no harmful impact from imaging.
fragmede 1y ago
Shit, you figured it out. It's not! That's whats been causing all the autism! Big ultrasound has been managing to keep this under wraps for decades!
- phanimahesh 1y ago
  Please don't be sarcastic for a possibility genuine question. It contributes to alienating the askers, not to mention the risk of some taking it quite literally.

If it can target and kill cancer, how can it also be safe for foetuses?

f1shy 1y ago

You can vary the frequency, power, energy, focus... is not the SAME ultrasound.

verisimi 1y ago
But surely it could cause some damage at a lower frequency, power, etc anyway?
- perilunar 1y ago
  Why “surely”? Most things that are harmless or even necessary at one level are deadly at another: heat, light, water, food, air… pretty much everything really. “Dosis sola facit venenum” (only the dose makes the poison)
  - verisimi 1y ago
    Using the example of a laser - you can have a powerful laser that can burn through metal. A far weaker laser (many magnitudes weaker) could still damage eye sight. Alternatively, water erodes mountains eventually. I don't think you can argue that ultrasound imaging is harmless or a treatment/dose. It might be that it does nothing. It might also be that it does something (like when it destroys cancer cells) only its far milder, and not an obvious observation. PS I know there are mild ultrasound devices to aid muscle recovery. These devices do something, presumably. If mild devices are acknowledged to impact muscles etc, some (mild probably) effect is occuring. Given there are occasions where these devices are known to have an impact on adults, why should we presume that there is no impact on the technology when it is looking at a developing foetus? PPS Even in studies that say there is 'no effect' from ultrasound imaging, there is a tolerance of up to 10% difference between the control and the subjects. PPPS And of course, sometimes the control is 'children who have only had 1 ultrasound' vs 'children who have 2 or more ultrasounds' - ie the control is not 'children who have who have had no ultrasounds' - ie we do not get true control studies.
- hgomersall 1y ago
  Potentially, but these things are well controlled and understood: https://www.bmus.org/education-and-cpd/cpd-resources/top-tips/medical-ultrasound-safety/ https://www.bmus.org/education-and-cpd/cpd-resources/top-tip...

BobaFloutist 1y ago

That's like asking how if a laser can cut through steel how lamps can be safe to have indoors.

verisimi 1y ago
Do you have a link or something that compares the power in both? I can't find one. This is the summary I get from chatgpt - comparing Histotripsy and ultrasound imaging | Property | Strongest Diagnostic / Imaging Ultrasound | Histotripsy (Therapeutic Ultrasound | | Frequency | 2 – 10 MHz (obstetric: 2–5 MHz; high-res imaging up to 15 MHz) | 0.25 – 3 MHz (sometimes up to 6 MHz) | | Pressure (Peak Negative) | Up to ~5–6 MPa (mechanical index limit ≈ 1.9) | 10 – 100 MPa (depending on type: intrinsic vs. boiling histotripsy) | | Intensity (Spatial Peak, Temporal Average) | Typically < 0.1 W/cm²; upper safe limit ≈ 0.72 W/cm² (FDA/AIUM) | 100 – 10,000 W/cm² (very high peak intensities) | | Pulse Duration | Microseconds (∼1–5 µs typical) | Microseconds to milliseconds (short bursts for mechanical disruption) | Its kind of hard to know what this means - some of the numbers seem pretty close/crossover - but I don't think saying the difference is akin to a laser and a light.
- an-honest-moose 1y ago
  There are 2 to 5 orders of magnitude difference in intensity. That alone is a pretty big difference.
  - verisimi 1y ago
    It's a big difference, but it is not obvious to me that there can be no harmful impact from imaging.

fragmede 1y ago

Shit, you figured it out. It's not! That's whats been causing all the autism! Big ultrasound has been managing to keep this under wraps for decades!

phanimahesh 1y ago
Please don't be sarcastic for a possibility genuine question. It contributes to alienating the askers, not to mention the risk of some taking it quite literally.