Doses to operators during interventional radiology procedures: focus on eye lens and extremity dosimetry

Abstract

The present study is focused on the personnel doses during several types of interventional radiology procedures. Apart from the use of the official whole body dosemeters (thermoluminescence dosemeter type), measurements were performed to the extremities and the eyes using thermoluminescent loose pellets. The mean doses per kerma area product were calculated for the monitored anatomic regions and for the most frequent types of procedures. Higher dose values were measured during therapeutic procedures, especially embolisations. The maximum recorded doses during a single procedure were 1.8 mSv to the finger (nephrostomy), 2.1 mSv to the wrist (liver chemoembolisation), 0.6 mSv to the leg (brain embolisation) and 2.4 mSv to the eye (brain embolisation). The annual doses estimated for the operator with the highest workload according to the measurements and the system's log book were 90.4 mSv to the finger, 107.9 mSv to the wrist, 21.6 mSv to the leg and 49.3 mSv to the eye. Finally, the effect of the beam angulation (i.e. projection) and shielding equipment on the personnel doses was evaluated. The measurements were performed within the framework of the ORAMED (Optimization of RAdiation Protection for MEDical staff) project.

Evaluation of a Suspended Personal Radiation Protection System vs. Conventional Apron and Shields in Clinical Interventional Procedures

“…Finally, Figure 5(c) demonstrates that the use of the mobile suspended lead-acrylic shield did not significantly impact the eye and head exposure when using Zgrav (Mean + SD = 0.00796 ± 0.0146 uSv/Gycm² with shield vs 0.00697 ± 0.0092 without shield, P = 0.14). This finding for Zgrav differs from widely reported results for conventional lead aprons where the mobile suspended shield reduced eye exposures [5,6,20,21].…”

“…Since the mobile suspended lead-acrylic shield was used in 100% of LAS procedures and 0% of Zgrav procedures in the wrist group (Table 1), this suggests ineffectiveness of the ancillary shields for reducing hand exposures, and that their omission does not increase exposures. These results were consistent with other reports [20,22,23]. When standardized to Total DAP (instead of fluoroscopic DAP), wrist exposure for all procedures in Phase II = 0.39 uSv/Gycm².…”

“…ZeroGravity differs from other weightless lead-apron substitutes by combining additional head shielding, rapid sterile entry/exit, and overhead suspension allowing body motion without floor-base motion [24,25]. The LAS technique, the most broadly studied protection method, is limited by difficulty maintaining ideal shielding position during interventional procedures, and the barrier discontinuity of multiple, separate devices [1,5,6,[18][19][20]. Alternatively, the ZeroGravity provides a single continuous enveloping barrier that shields the top of the head through the lower tibias (broken only by protrusion of the arms through the arm flaps).…”

“…Combinations of lead apron, attenuating drapes, accessory shields and glasses have been studied using phantoms to extrapolate radiation protection theoretically provided to the practicing interventionalist [13,14,[20][21][22]26,27]. Although phantom studies provide preliminary information, application to clinical practice is problematic due to many dynamic factors including large patients, interference with operator's hands or arms from accessory shields, and inability to use shielding in certain image receptor obliquities or operator stances.…”

“…Lead glasses do not protect the cervical bone marrow and nervous system where even moderate doses of radiation are associated with elevated incidence of nervous system tumors [1,11,[15][16][17]. Ancillary protection including table shields, hanging leadacrylic shields, and attenuating drapes reduce scatter when positioned properly, but are sometimes awkward and difficult to position due to interference with operator, patient, or image receptor, especially with oblique projections where scatter may increase several-fold [1,5,6,[18][19][20][21]. These shields produce a discontinuous barrier that is not always in the path of scatter and may not be used without a lead apron.…”