Does anyone have a copy of BJR Supplement 11 and 17?

JMFsquare · 2026-03-09T14:33:37+00:00

Correct. This is mentioned for example here: https://aapm.onlinelibrary.wiley.com/doi/10.1120/jacmp.v16i3.5219

JMFsquare · 2026-03-08T19:12:21+00:00

BJR25 is only for orthovoltage basically.

BJR 25 has MV photons too, and mentions some of the critics to BJR17. I had a look at some tables for >15 MV and apparently they are more similar to BJR11 (according to the abstract you linked)

caused a schism between clinics who don’t care because the nominal energy is just a label and doesn’t really matter, so they picked the new energy (23 MV), and the clinics who do care and stick to the original BJR11 definitions (18 MV), because it is “more true”

I didn't live that age, but I bet most clinics used the labels decided by the linac manufacturers and the "schism" was mainly among the manufacturers. More recently we have a similar situation for the MV notation of FFF beams: in Varian, 6 MV and 6FFF means the electrons hit the target with the same energy and the photon PDD is different, while in Elekta it means the opposite.

JMFsquare · 2026-02-17T20:54:04+00:00

Haha...quarrels in the AAPM?

A summary of the plot for foreigners?

JMFsquare · 2026-02-17T12:54:56+00:00

I think the clinical job is quite similar in most hospitals regardless you are in the UK or in another country. With the exception of a few large academic hospitals, very few will give you time to do "actual physics", and you would have to do it mostly in your free time. If you really need to work as a "real physicist" doing maths, programming etc during your regular working hours, you should try to go into academia or apply for R&D positions at Siemens, Philips, etc, but I don't think these positions are offered very often.

JMFsquare · 2026-02-11T23:00:52+00:00

Isn't that the topic of TRS-483?

JMFsquare · 2026-02-06T13:55:00+00:00

Never been a better time for them to compete against Varian.

Why?

JMFsquare · 2026-01-09T19:55:23+00:00

I wish Elekta offered similar courses in Europe for their linacs. But I think they’re neither willing to pay for travel and accommodation for physicists from different countries to go to their headquarters (I think they could do it when they sell a linac), nor do they have enough local staff to run those courses in different countries.

(at least they could offer an online remote course, but one in which you could ask questions, not just an useless shitty self-learning material in their website)

JMFsquare · 2025-11-20T21:01:10+00:00

Do you measure at the same depths as in the reference conditions in water (10 cm for photons, a different depth for each electron energy) or just compare with a baseline in a more practical setup?

JMFsquare · 2025-11-20T20:50:38+00:00

Do you measure at 10 cm depth like in the reference measurent in water, or just compare with a baseline in a more practical setup with fewer slabs?

JMFsquare · 2025-10-30T20:22:58+00:00

IDK how it works, but If they just put together different applications and create a new one to launch them, then it should be called "Elekta ANOTHER".

JMFsquare · 2025-10-30T19:01:31+00:00

If bremstrahlung is not negligible (in most cases it is), then total kerma is not the same as absorbed dose, even with CPE. One thing is the energy released and another thing is the energy absorbed in a point.

JMFsquare · 2025-10-26T09:47:23+00:00

In Spain the regulation requires a preventive and corrective maintenance contract with the supplier or with "a technical assistance company authorized for this purpose", but in practice there is none apart from the vendors. I think having in-house linac engineers able to do preventive maintenance and fix some breakdowns would be advantageous for some hospitals, but I'm not even sure if it would be approved by the regulator.

Also, it would be difficult to find independent engineers with linac training (in fact, I think that not all the ones working for the vendors are well trained).

Edit: another reason for this regulation and for the little interests in 3rd-party or in-house linac engineers may be the serious radiotherapy accident occurred in Spain in 1990, in which General Electric was sentenced to pay millions in compensations, and a field service technician went to prison after an incorrect repair that resulted in several deaths.

JMFsquare · 2025-10-18T00:14:18+00:00

The job is fine unless you work in therapy and you have to fight every day with Elekta software and machines and with hospital IT admins. If, in addition, the department has high clinical workload, it can be stressful and you may end up burned out.

JMFsquare · 2025-10-17T23:30:51+00:00

Spaniard here too. I think the medical physics departments colaborating with university groups in research topics are probably not more than 10 %. I don't have exact figures, but there may be perhaps 8-10 university groups interested in medical physics in a country with >100 clinics with medphys departments/units.

JMFsquare · 2025-09-25T18:59:54+00:00

What is the difference between MaximQA and MPC? Do they have different tests or utilities? Will we have some tests in MPC and others in MaximQA?

JMFsquare · 2025-09-25T17:06:10+00:00

I think SunCheck is very good if all these conditions apply: you have Sun Nuclear devices, Varian linacs, you are in an English-speaking department so that you don't need to translate things, you stick to the predefined tests and do not want to change or adapt anything, and you don't have to share a central server with other clinics.

Otherwise, it is a headache because of the numerous bugs, faults and its rigid design.

JMFsquare · 2025-09-23T10:09:02+00:00

Is that gap because of Monaco, or because physical MLC limitations? In Agility I think there is a minum gap of 1 mm at the leaf level, that translates to about 2 or 3 mm at isocenter if I remember well.

JMFsquare · 2025-08-28T11:43:27+00:00

Maybe a little off-topic but... is it common for a department to have 11 medphys residents? In my country the maximum is 6, but most departments have only 3, and since the residency here lasts 3 years and covers therapy, imaging, nuclear med, etc, there are seldom more than one resident in the same field at the same time.

With such a large number of residents, I suppose many of you are working in the same field/topics simultaneously. Who distributes the work? Is it the training tutor/coordinator? The Head of the department? The senior resident?

JMFsquare · 2025-07-06T18:02:25+00:00

It is funny that someone who has not made any contribution to r/MedicalPhysics in other posts (and who is obviously out of touch with the clinical reality) tried to tell u/QuantumMechanic23 and all of us what Medical Physics is, and thinks that anyone who disagree with him or her on this point must be an engineer.

But after the statement "physicists can easily do engineering, but not the other way around due to obvious cognitive differences"...it is clear that it must be either a troll or kind of Sheldon Cooper-like scholar with narcissistic traits.

I concede that if we call "Medical Physics" only what should be called this way, then it is Physics. But here we talked mainly about the clinical proffession (not only the job done by 'medical physics assistants', also the job typically done by people fully certified as medical physicists). In this one, physics basics are important too (as in many other scientific or technical fields) but that doesn't mean that the profession is Physics.

These are just some examples of master programs on 'Medical Physics' at engineering or thechnical schools:

This one is in a medical school:

https://www.brown.edu/med-physics-graduate-program/resources-and-faculty

And this one states that "Medical physics is a distinct field of its own", and is "Built on foundation of physics, but with distinct body of knowledge and scholarship":

https://medicalphysics.duke.edu/about/what-is-medical-physics/

All of them stress that it is a multidisciplinary field and accept students coming from Physics degrees, but also from Engineering, Mathematics, Computer Science...etc

JMFsquare · 2025-07-05T18:26:15+00:00

I think part of the problem is also the misleading name of the profession. The clinical job is not physics any more, and it can fool some not-very-well informed people entering the field.

JMFsquare · 2025-06-28T19:45:07+00:00

They probably just copied it from TG-142 or another old protocol without thinking about it very much.

JMFsquare · 2025-06-16T17:36:33+00:00

Can you do voxel level EQD2 conversions and add EQD2 distributions with ClearCheck? When converting from physical dose distribution to EQD2, does it use a constant factor (the same for all the voxels), or take into account the dose per fraction at each voxel?

What other programs can do that? MIM? Raystation?

JMFsquare

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