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Questions tagged [medical-physics]

A field of applied physics dealing with the application of physics to diagnosis and treatment of diseases.

A field of applied physics dealing with the application of physics to diagnosis and treatment of diseases. Major subspecialties in medical physics include imaging medical physics, therapeutic medical physics, nuclear medical physics, and medical health physics.

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How specifically does an MRI machine build an image from received radio waves?

Unlike the excellent Wikipedia page on ultrasound imaging, the one on MRI only explains the principle theory behind MRI - that oscillating strong magnetic fields cause water molecules to emit radiowaves - without explaining how his is applied to…
Mr. Boy
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How radioactive is uranium?

Look at this video: People face uranium directly. Does this mean the radioactivity of uranium is very weak? Because its half-life is very long? Personally, I would never dare to touch any radioactive element. I also remember seeing people holding…
John
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Could cell-phone radiation cause cancer?

It is very crucial that I ask whether it could and not whether it does. I do not mean to be the least controversial. To my surprise, having read "Physics for Future Presidents" by Richard Muller last year, I've come across a sentence of the sort…
Wesley
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How much radiation do nuclear physics experiments expose researchers to nowadays?

I am curious about how much radiation do experimental nuclear physics researchers/students suffer in nowadays research environment. I know this may be a dumb question, but I have can found answer nowhere.
OpticalQuantumEngineer
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Reverse blood flow in an IV

When the IV drip for a patient is completed, the patient's blood will flow back. This is apparently due to the pressure difference. However, IV needles are inserted into veins in the direction of blood flow. Hence, the blood is flowing against the…
Starlight
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Proton therapy in cancer treatment

Why are protons used in cancer therapy ? Is there any advantages compared to classics X-rays treatment or electron treatment ?
Cedric H.
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Is my tritium keychain emitting significant amounts of radiation?

I recently purchased a tritium keychain, composed of a small glass vial of tritium gas partially enclosed in a stainless steel fob. Here are the Amazon links so you can see a specific example: Link for vial Link for fob The glass vial is 12mm long…
Dacromir
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Why use gamma over alpha radiation?

In radiotherapy, the goal is to kill as many cancer cells in a localised area without killing normal cells right? So what possible reason would there be to use gamma irradiation over alpha irradiation? Gamma is not as good at ionising and damaging…
Hisham
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How is it possible for an Ultrasound device to correctly interpret a negative density change in tissue?

I understand the principles of Ultrasound Imaging, and the mathematics behind sonar velocity, impedance, and reflection. I also understand that an Ultrasound device recieves an echo produced by impedance (~ density) changes and can calculate the…
Keno
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In MRI why don't metals in the body get ripped out?

Why doesn't the strong magnetic field cause iron in the blood to at least pool to the surface of the body.
Aaron
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Is EM radiation from a domestic main electric supply harmful?

Pardon me if this not exactly the right site for asking this question but one of my friends sleeps in a room directly next to the main electric supply of his house (220V, 50Hz in India) and insists that the EM radiation from the electric wire may…
User1201
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How much Uranium would a country like Iran need to produce for supplying its Technetium needs?

This is not a question about politics, although the motivation is a political situation. Iran, which enriches Uranium to a level of $60\%$ $\rm{^{235}U}$, is claiming it has civilian uses for this enriched material. I assume there could be more…
einpoklum
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In radiotherapy, why do normal tissiue or organ cells not die of radiation?

In radiotherapy, why don't normal tissiue cells or organ cells in the way of incoming radiation die, but tumours die instead?
PhysicsEnginering
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High pressure cryonics

In this link, it is suggested to use high-pressure cryonics to freeze living cells, tissues or small organism as opposed to various and potentially toxic anti-freeze agent. The core idea is that over a certain pressure, ice is anamorphic and will…
Anon21
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How are photons told apart by a PET scanner?

From what I've read, a radiopharmaceutical, such as FDG, enters a body and emits positrons that annihilate with electrons, emitting two equal gamma rays in opposite directions. Diametrically opposite detectors pick up these photons and extrapolate…
Tobi
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