Effectiveness of a lead cap in radiation protection of the head in the cardiac catheterisation laboratory.

Introduction During the past 30 years, interventional cardiology has advanced dramatically resulting in outstanding increases in occupational radiation exposure of interventional cardiologists. Despite the remarkable changes in fluoroscopic procedures, radiation protection technology is not much different from how it was decades ago. Moreover, new evidence on occupational radiation suggests that low doses of ionising radiation exposure may be associated with the development of cancer in interventional cardiologists and radiologists1-6. The brain is of particular interest, because it is one of the least protected organs during interventional procedures2. The trunk and the thyroid are protected with lead aprons, and the eyes are protected by lead glasses; however the head is completely exposed. The annual head dose sustained by a cardiologist generally ranges between 20 and 30 mSv, and in some cases may reach up to 60 mSv per year7. This indicates a dose 10 times higher than whole body exposure8. Ceiling-suspended lead shields reduce radiation doses to the brain but they are designed to protect the face and head from primary scatter radiation from the patient. Therefore, a significant amount of secondary radiation scattered from the laboratory walls may reach the operator’s head, despite the presence of a ceilingmounted glass shield. Until now, operators have not used protective garments to protect their head from radiation.