Unprotected operator eye lens doses in oncologic interventional radiology are clinically significant: estimation from patient kerma-area-product data.

PURPOSE

To correlate operator lens dose to patient-delivered kerma-area-product (P(KA)) to evaluate the usefulness of P(KA) as a surrogate for operator eye dose if collar monitor readings are unavailable or deemed unreliable, and to evaluate if unprotected lens dose is clinically significant.

MATERIALS AND METHODS

A retrospective review of peak skin doses for consecutive interventional radiology procedures performed during 2006 that had P(KA) estimates recorded was performed. Unshielded operator lens dose equivalents (LDE) were obtained from dosimetry monitors worn outside the collar shield of operating interventional radiologists. Operator LDE were correlated with patient P(KA).

RESULTS

Average LDE for 2006 was 35.7 mSv ± 32.7 (range 5.2-89.9 mSv). Patient-delivered P(KA) correlated directly with LDE, where 1 Gy cm(2) to the patient resulted in an average of 4.2 μSv to the unprotected eyes of the primary operator (r(2) = 0.7).

CONCLUSIONS

P(KA) may be useful as a surrogate measure of operator LDE if collar monitor readings are unavailable or deemed unreliable. For this study, the dose-effect threshold for cataract formation could be surpassed for some physicians within 11 years if lens dose-mitigating strategies are not routinely employed.