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Accuracy assessment phantom for surgical devices

The objective of this study was to design and develop a phantom and an accuracy assessment protocol for surgical devices used at Oulu University Hospital, Oulu, Finland. The main criteria for this phantom were that it needed to be manufactured with sub-millimetric error between the calibration holes, easy to use and dimensionally suitable for MR scanners and an O-arm used at Oulu University Hospital. The designed phantom was used to assess the accuracy of the optical tracking and electromagnetic tracking system (EMTS) modalities of a commercial surgical navigator and the image quality of an O-arm. The studies showed that the design of the phantom fulfilled the requirements set for this study. The phantom functioned well and it was easy to use. It also had enough calibration holes to ascertain the trend of the accuracy and image errors. The present accuracy assessment protocol proved to be a practicable quality control tool for accuracy analysis in the hospital.