[Personnel exposure during interventional radiologic procedures]

Intervention radiology, known also as intravascular surgery, is a new medical specialisation that develops very rapidly. Radiological procedures performed under fluoroscopy include: dilatation of stenosed vessels, recanalization or vascular embolization and angioanastomosis. Although these procedures have been initiated by radiologists, the majority of them are performed now by physicians who are specialised in medical disciplines other than radiology (cardiologists, vascular surgeons, gastroenterologists, etc.). All these specialists are always aware of the fact that during radiological procedures, both the personnel and the patients are at risk of ionizing radiation. For that reason monitoring of the exposure in this occupational group is of particular importance. Bearing in mind that members of surgical teams are often in direct contact with x-ray tube, it is assumed that routine individual dosimetry of staff occupationally exposed to x-rays do not provide adequate assessment of the exposure risk. This paper describes measurements carried out among operating surgeons who perform the following procedures: cardiological interventions (percutaneous transluminal coronary angioplasty (PTCA) and bypass with preceding coronarography); neuroradiology (aneurysm embolization); and intravascular surgery within abdominal cavity (TIPS, nephrostomy). Dosimetric assessment was carried out in operating surgeons who are exposed mostly among the members of surgical teams as they have to be in direct contact with radiation sources. A comprehensive assessment of exposure included the following measurements: equivalent dose for the hands (measured by a specially designed finger dosimeter); equivalent dose for the trunk protected by a lead apron (a dosimeter placed under apron); and equivalent dose for the neck (a dosimeter placed on the upper, external edge of apron). In addition, a dose product and the surface of primary beam were measured (Diamentor dosimeter, PTW, Frieburg) which allowed to define the correlation between the entrance air kerma, measured with thermoluminscence dosimeters, and the amount of primary radiation emitted during the monitored procedure. In all, the surgical teams were monitored during 42 intervention procedures. The results of the study revealed that an operating surgeon is most exposed. The values of an annual effective dose and an annual equivalent dose for the hands and eyes, estimated for individual procedures, were as follows: (a) cardiological angioplastic procedures: effective dose--25 mSv, equivalent dose for the hands--438 mSv, equivalent dose for the eyes--265 mSv; (b) intravascular angioplastic procedures within the abdominal cavity and neuroradiological procedures: effective dose--4 mSv, equivalent dose for the hands--360 mSv, equivalent dose for the eyes--41 mSv. It should be stressed that the aforesaid maximum doses do not exceed relevant standard annual limits binding in Poland.