Radiation doses to patients in neurointerventional procedures.

PURPOSE To evaluate stochastic and deterministic risks associated with neurointerventional procedures for the patient. METHODS Eight neurovascular interventional procedures were evaluated to determine the entrance skin dose and effective dose for the patient. Dosimetry was done with thermoluminescence dosimeters. The highest dose on the patient9s head was recorded as the maximum entrance skin dose. The equivalent dose was obtained by conversion of the dose-area product using published conversion tables. RESULTS The maximum entrance skin dose varied from 129 to 1335 mGy. The mean effective dose was 1.67 mSv with a range of 0.44 to 3.44 mSv. No deterministic effect has been encountered. Stochastic risk linked to the highest effective dose value was approximately one death by fatal cancer for every 6000 procedures, according to the new International Commission on Radiological Protection coefficient. CONCLUSIONS Because no deterministic effect has been detected, and stochastic risks were very low, radiation hazard to the patient is a minor consideration in deciding whether to undertake a neurointerventional procedure.