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The purpose of this study was to evaluate radiation doses to the patients and operators during interventional cardiology procedures, with a particular focus on the transcatheter aortic valve implantation (TAVI). Patient doses for 5549 diagnostic and therapeutic procedures and 76 TAVI were examined, as well as occupational doses to Cardiology Department operators. The average patient dose for TAVI was double that of PTCA and six times higher than a simple CA; statistically significant differences were shown in the average patient dose for both transfemoral and transapical access; the measurements show a corresponding increase in the average occupational dose for the cardiologist. Interventional cardiology could increase the collective dose and occupationally exposed worker doses; this increase could be significant if the use of certain procedures is extended to younger people; particular attention in the choice of procedure, optimisation and staff education and organisation is therefore suggested.

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The use of immobilization plastic masks in head and neck radiotherapy can partially eliminate skin benefits derived from the utilization of megavoltage photon beams. Filters and blocks between the patient and the accelerator can further increase the skin dose value. In this study, the increase in surface dose due to 2 and 3.2 mm of plastic material utilized for patient immobilization was measured. Then, the effect of blocking trays, wedges, and blocks on skin dose in typical conditions for head and neck irradiation was evaluated. The measurements were obtained with a NE2534 chamber (Markus type) on a perspex phantom for 6 MeV x-rays from an accelerator.

The goal of establishing prompt localization of the malignant spread or recurrence of a tumor has found a powerful solution in the definition of follow-up protocols, which include the indication for CT scans on an annual or semiannual basis. In the case of long-surviving patients, however, this approach will lead to a considerable integrated dose level over a period of several years after recovery from the illness. Pathologies treated primarily by surgery and/or chemotherapy have been considered, not taking into account cancers treated with adjuvant or radical radiotherapy. Given that the most likely protocols for these cancers often call for total body scans, an estimation of the consequent effective and organ doses can be performed with acceptable accuracy. The data acquired from five centers have been collected and the related effective and organ doses calculated by means of IMPACT software. Use of the effective dose concept, however, has lately become the subject of criticism, and the recently proposed Effective Risk Model has therefore also been applied. The evaluated absolute additional risk of second tumor induction ranges between 0.1% and 10%, depending primarily on age and pathology. These results depict this additional risk as an issue of significant importance for clinical practice. A revision of follow-up and scan parameter protocols, as well as the introduction of new algorithms for dose reduction, could significantly improve the risk-benefit ratio for all the pathologies studied.

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