933: Tattoo

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(Corrected comment about electron and gamma ray therapy, and added explanation regarding lethal doses to horses)
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The joke in the comic is that Cueball got this barbed wire tattoo to look tough, but it pales in comparison to the tattoo from (or for) the cancer removal or treatment. This is ironic because people who get barbed wire tattoos believe themselves to be tough. It is kind of funny because Cueball has his whole shirt off just to show a biceps tattoo.
 
The joke in the comic is that Cueball got this barbed wire tattoo to look tough, but it pales in comparison to the tattoo from (or for) the cancer removal or treatment. This is ironic because people who get barbed wire tattoos believe themselves to be tough. It is kind of funny because Cueball has his whole shirt off just to show a biceps tattoo.
  
The title text mixes up two different types of {{w|radioactivity}} – {{w|Beta radiation}} ({{w|electrons}}) and {{w|Gamma radiation}}. The electrons from the beta radiation only do harm the skin, just because it doesn't move at 99.8% of the speed of light. But the gamma radiation can reach every point at the inner body. If this is not focussed to the location where the cancer is it could kill the individual or even a horse.
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The title references gamma ray therapy after describing electron linear accelerator-based treatment systems; however, technically gamma ray therapy only refers to radionuclide (i.e., Cobalt-60) based radiation therapy systems. In regards to a 90-second session killing a horse, typical dose rates of modern radiation therapy systems are of the order of several Gray per minute for the field sizes used, for example, in the treatment of {{w|breast cancer}}. It is feasible that a single 90-second delivery of radiation could deliver over 10 Gy in a single instance to the specific areas of the body that could be fatal, such as neuropathy or radiation induced liver disease.
  
 
==Transcript==
 
==Transcript==

Revision as of 03:28, 15 April 2014

Tattoo
I calculate that the electrons in radiation therapy hit you at 99.8% of the speed of light, and the beam used in a 90-second gamma ray therapy session could, if fired with less precision, kill a horse (they did not let me test this).
Title text: I calculate that the electrons in radiation therapy hit you at 99.8% of the speed of light, and the beam used in a 90-second gamma ray therapy session could, if fired with less precision, kill a horse (they did not let me test this).

Explanation

Ambox notice.png This explanation may be incomplete or incorrect: The title text isn't explained, and I want to know if it could actually kill a horse.
If you can address this issue, please edit the page! Thanks.

An Oncologist is a doctor who specializes in the treatment of cancer. This comic is certainly related to the breast cancer issue that Randall is going through with his fiancé. Megan in this comic has a tattoo for the alignment lasers of the radiotherapy machine which will fire a beam of radiation with sufficient intensity to kill the cells in the targeted area. A common such machine is a linear accelerator or "Linac" which accelerates electrons to very high speed, these can then either be used to generate high energy Xrays to treat the patient, or the electron beam itself can be used (both are types of radiation). Commonly when radiotherapy is used as part of breast cancer treatment some combination of both is prescribed. In order to allow healthy tissue to recover better, rather than deliver all the radiation in one go, the treatment is delivered a little bit each day over the course of about a month. It is therefore vital that the radiation can be delivered to the correct target area day after day, and this is done by lining up the alignment lasers of the linac with the skin markers - that is Megan's tattoo dots. It may not be considered a "traditional" tattoo (because it says it was done by her Oncologist and not in a tattoo parlor).

In the last frame, it is mentioned that Cueball has a barbed wire biceps (the comic erroneously says "bicep" which is not a word, the s is part of the originally latin word, not a plural s) tattoo, which is common in the US as a tattoo that people get when they want to seem tough, even if they aren't tough already.

The joke in the comic is that Cueball got this barbed wire tattoo to look tough, but it pales in comparison to the tattoo from (or for) the cancer removal or treatment. This is ironic because people who get barbed wire tattoos believe themselves to be tough. It is kind of funny because Cueball has his whole shirt off just to show a biceps tattoo.

The title references gamma ray therapy after describing electron linear accelerator-based treatment systems; however, technically gamma ray therapy only refers to radionuclide (i.e., Cobalt-60) based radiation therapy systems. In regards to a 90-second session killing a horse, typical dose rates of modern radiation therapy systems are of the order of several Gray per minute for the field sizes used, for example, in the treatment of breast cancer. It is feasible that a single 90-second delivery of radiation could deliver over 10 Gy in a single instance to the specific areas of the body that could be fatal, such as neuropathy or radiation induced liver disease.

Transcript

[Megan is in the panel. Megan points at her chest.]
Megan: I just have one tattoo - it's six dots on my chest, done by my oncologist.
Megan: I need them for aligning the laser sights on a flesh-searing relativistic particle cannon,
Megan: So it will only kill the parts of me
[Dramatic zoom, the panel background is black, with white text.]
Megan: That are holding me back.
[The panel is larger, revealing who they're talking to.]
Megan: But your barbed wire bicep tattoo is pretty hardcore, too!
Cueball: No, it's OK. I'll just go put a shirt on.
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Discussion

So it kills her appendix, spleen and what else? I'm pretty sure bad attitude isn't an organ. Davidy²²[talk] 09:14, 9 March 2013 (UTC)

I think the parts holding her back are the cancer cells Dawfedora (talk) 15:50, 7 August 2013 (UTC)
I though it meant she was going to destroy her heart, as her feeling were holding her back, and she convinced her oncologist to specially tattoo her for this purpose. 108.162.245.114 (talk) (please sign your comments with ~~~~)
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