A comparison of two peak skin dose metrics calculated by patient dose management systems: implications for clinical management

Abstract

Objective: The patient dose monitoring systems DoseWatch and DoseWise were compared to evaluate their reported patient Peak Skin Dose. Methods: 20 patients with the highest Peak Skin Dose on DoseWise were obtained; the values were converted to a Reference Point Air Kerma (RPAK) value and used for comparison. These patients were accessed in DoseWatch to obtain the recorded Worst Case RPAK. The co-ordinates for the position were obtained for each patient to find a primary and secondary angular position for the peak skin dose. The two positions produced by the two softwares were compared. Results: There is a mean deviation of over 0.5 Gy between the two software packages when comparing the calculated maximum skin air kerma Peak skin dose from DoseWise and the Worst Case RPAK from DoseWatch. Conclusion: We have shown mean deviations between these two systems. This difference is enough, for higher peak skin absorbed dose patients, to change the management of patients, so local services must understand their models to properly implement patient management. Advances in knowledge: Neither system is incorrect, but these differences show that a deeper understanding of the analysis limitations is required to properly inform post-procedural high-skin dose follow-up procedures.