Report of the International Symposium on Radiological Protection of Patients

The Symposium was held 2-4 October 2006 in Málaga, Spain. It was organized at the initiative of the Spanish Society of Radiological Protection supported by:

• the Spanish Society of Medical Physics,
• the Consejo de Seguridad Nuclear,
• the Spanish Ministry of Health,
• the Pan American Health Organization (PAHO),  and
• the International Commission on Radiological Protection (ICRP).

At the request of the Spanish organizers, the IAEA agreed to cooperate in the event by providing technical support of the Scientific Officer. In addition, the following national professional bodies cooperated in the event:

• Society of Medical Radiology,
• Association of Radiotherapy and Oncology,
• Society of Nuclear Medicine,
• Society of Paediatric Radiology,
• Society of Diagnostic Imaging of the Breast,
• Society of Vascular and Interventional Radiology, and
• Association of Radiology Technologists.

The symposium was attended by 175 participants. It lasted for two and a half days, and simultaneous Spanish-English translation was provided for one full day, i.e. the day in which most foreign invited speakers gave their talks.

The following summarizes the global conclusions of the symposium:

• Recent UNSCEAR data do not indicate a substantial change in the global risk coefficients.

• MDCT has opened new uses of CT, particularly in cardiology. The trend is a continued growth, as CT is deemed to replace conventional angiography, intravenous urography, barium studies and conventional radiographs; new CT equipment provides features and flexibility in the parameter selection, which allow substantial improvements in optimization of protection, with the only limitation posed by the quantum noise, which is acceptable in each clinical indication. Research and consensus of professionals is needed to assess the acceptable noise.

• The use of PET/CT is increasing dramatically. So far, the main use is in oncology, but its use in cardiology and other areas is also expected; methods of exposure reduction and medical protocols will gain an important place.

• Procedures with higher exposure, such as CT and interventional, are increasingly used for children. There is a considerable, unutilized opportunity for optimization of protection in paediatric radiology, both in new equipment as well as in its use; scrutiny in the prescription of examinations, exposure awareness and training are identified as essential tools.

• Interventional procedures also grow at a fast pace; opportunities for optimizing protection are not yet exploited; the use of guidance (reference) levels, and a closer interaction between interventionalists and physicists is needed.

• Digital mammography is progressively replacing film-screen mammography; there is a promising development of new image receptors, with very high detection efficiency and very low electronic noise, which have the potential for increasing contrast and reducing exposure.

• New techniques in radiotherapy are aimed to achieve a better tumour control with lower normal tissue complications probability; in new techniques, such as conformal and intensity modulation radiotherapy, the high-dose volume is smaller but the low dose (2-4 Gy) volume is larger than with conventional techniques. Since most documented second cancers are induced in the high-dose volume, the speaker maintained that the expectation of second cancer from the new techniques should not be higher than with conventional techniques, as some recent papers have warned. The potential for accidental exposure with the new techniques should be analyzed and followed up.

• Informed consent by patients is an increasing demand in many countries. This is particularly true in procedures with higher exposure, such as interventional procedures using X rays and computed tomography. Concise and objective information about exposure for patients is becoming an obligation for the medical community.