Sujet Les questions auxquelles on n'a pas les réponses mais un AFien peut les avoir

Des problèmes biologiques sont évoqués suivant la puissance utilisée pour les RF.

Conclusions
Perhaps the safest component of the MRI exam is the static magnetic field. By examination of the current literature, and within the limits of our knowledge, the only health hazards significantly associated with the exposure to static magnetic fields are related to the presence of ferromagnetic materials or cardiac pacemakers in patients. Almost all of the more than 100 million MRI exams performed since early 1980 were completed without any evidence of harmful effects to the patient from the static magnetic field. However, due to the signal to noise advantages of high field MRI systems, increases in the static magnetic field are inevitable.

The second potential source of risk in MRI exams arises from the use of pulsed field gradients. High slew rates can cause peripheral nerve and/or cardiac stimulation to the patient. However, peripheral nerve stimulation, which can be painful although not harmful to the subject, has a threshold lower than the level required for potentially dangerous cardiac stimulation. Present day MR systems typically operate below nerve stimulation levels thus, at the current state of the art, cardiac stimulation is very unlikely.

RF power deposition represents the greatest risk for patient safety in MRI exams. There is widespread agreement among scientists in considering that a local increase in temperature of 1°C in a healthy individual is absolutely free of risk. In MRI exams, an SAR of 8 W/kg could be used, but for short enough exposures so as not to produce a more than 1°C core body temperature rise. However, in terms of safety, it would be desirable that a clinical MR system be equipped with a sensing phantom that could shut off the power to the RF source when SAR levels approach the limits established by international safety guidelines.

From these considerations, our hope is that the knowledge of magnetic resonance imaging systems safety can not only help guide the future design of these instruments, but also affect the selection of procedures in order to ensure safe, efficacious, and efficient system operation

Mais surtout, il y a une démarche scientifique à suivre quand on veut établir une "vérité" (ou plutôt "ce qu'on sait de mieux" sur un sujet), et ca ne consiste pas à chercher les arguments qui confortent l'a-priori qu'on en a. Et même, au contraire.

Sincèrement, j'ai l'impression que t'as juste pas envie d'y aller de base et que tu cherches un prétexte.

Sincèrement, j'ai l'impression que t'as juste pas envie d'y aller de base et que tu cherches un prétexte.

En 2016 en Sibérie, des spores d'anthrax vieilles de 70 ans se sont libérées du cadavre d'un renne après le dégel d'une couche de permafrost.

un peacemaker