The July Radiological Protection Studies Group of the SPR meeting was attended by two professionals in the area: Dr. Lisa Suzuki, responsible for pediatric radiology at Hospital das Clínicas and Hospital Sabará, and Dr. Paulo Roberto Costa, assistant professor of Physics of the Institute of Physics of USP (IFUSP) and specialist in Physics of Radiodiagnosis by ABFM. Dr. Hilton Muniz Leão Filho was present and made comments on the presentations.

Dr. Lisa Suzuki presented the first class on dose optimization in the places where she works. She spoke about important terms such as CTDI, DLP, FC (correction factors), effective dose and SSDE (Size Specific Dose Estimate).

According to her, the hospitals follow a basic protocol, with adjustment according to the weight, with serious leanings and a work of conscientization of all the professionals. And she explained that doctors have become accustomed to the slightly noisier images, as they are sufficient for the diagnosis, even though it is lower than that practiced in other hospitals.

She emphasized that the reading of children’s exams is always more difficult to understand the reference levels in diagnosis and attainable doses, and it is necessary to create adequate parameters. In addition, there are external factors that can harm the image: for example, containment bands when the dose is very low.

Her final considerations were:

• Dose reduction is important (adjustment of dose by weight / diameter, lean protocols and precise indications);
• “Hyper-reduction” should be avoided (depending on the type of equipment) and may impair the diagnosis, which is the main objective;
• The rational use of methods should be widely disseminated among radiologists and non radiological physicians;
• The correct information on the risks and benefits of the methods that use the radiation to be emphasized.

After the presentation, Dr. Hilton commented that people on duty (usually younger) complain about the difficulty of diagnosing lower-dose imaging and asked if it is possible to measure it. Dr. Lisa thinks that this difficulty can be solved, but that she could not answer with precision because she has not yet been able to evaluate this aspect.

Next, Dr. Paulo R. Costa spoke about DRLs, optimization in pediatric CT and professional qualification. Showed the Diagnostic Reference Levels (DRL) concept, existing since the 1990s that has become the repertoire of radiologists and physicists. He also spoke about the CRP commission, from which it was understood from a practical and clear point of view what institutions should do to obtain reliable values of DRL.

About pediatric DRL, your comment was that there are many challenges. It is necessary to have information from the database, collected in a coherent way. He emphasized that Brazil is a continental country and that, therefore, there are huge differences from one place to another. In any case, he stressed that it is necessary to give more weight to the benefit, which in most cases far outweighs the risks. This aspect is important even for parents, because communication with them is risk. It must be said that there is the benefit of the examination for children, when indicated.

He talked about Dr. Donald Frush, creator of the Image Gently, and spoke about the importance of knowing the needs for radiological protection. For example, in the pediatric area, it must be understood that the child is not a small adult. There are anatomical differences. According to him, the pediatrician knows this, but other professionals also need to understand this concept. The qualification of the medical physicist in this sense is also important.

Also, he spoke about the campaign Bonn Call for Action, emphasizing the principles of radiation optimization and protection – noting that this approach should consist of a regular updating of reference levels in radiation protection.

Finally, he talked about how to develop equipment in a single category, patient risk indicators should be measured accurately in all diagnostic imaging procedures. And he left the question: “How much do we reduce in organs when we optimize?”, with the link to the project available in the Journal of Applied Clinical Medical Physics: https://doi.org/10.1002/acm2.12505. 

In the end, everyone discussed the presentations and talked about the tendency to divide responsibilities in the services, where the radiologist gives the report, the technician has to take the exam with the proper dose and the physicist, perhaps, is today the best prepared one to deal with the scenario as a whole.

Participate online at the next meeting on August 5: http://bit.ly/latinfafe05-08-19.