Interventional cardiologists receive the highest occupational radiation doses in the medical field. Recent anecdotal reports of brain tumors in these workers have raised the concern that their occupation could be linked the development of the lesions, specially because of the laterality of the tumors reported. In a recent publication, from the 26 cases where the side of the lesions were available, 22 (85%) were on the left side, which is usually the side closest to the radiation source.
Besides brain lesions, ionising radiation can also play a role in cognitive impairment. Up to 90% of the patients treated with radiotherapy for brain tumours show impaired verbal and spatial memory. Although the doses received by these patients are several orders of magnitude higher than the doses received by interventional cardiologists, in recent studies evaluating cognitive function, individuals occupationally exposed also showed poorer memory performance than non-exposed ones, raising the concern that even for low doses such side effect might occur.
However, the correlation between exposure to low doses of ionising radiation and the development of brain tumours remains controversial. In studies comparing large cohorts of physicians who performed interventional procedures with psychiatrists, who were not occupationally exposed to radiation, no increased risk of death from brain tumors was found.
A major drawback in the correlation between occupational exposure to low doses of ionising radiation and the onset of brain tumors is the lack of accurate assessment of the doses received by the brain tissue. Interventional cardiologists are routinely monitored, however, no correlation has been yet established between the doses measured and the dose to the brains. Furthermore, the use of protective devices, such as ceiling suspended screens and leaded caps or hoods, can influence the doses, and also have to be considered.