\input zb-basic \input zb-ioport \iteman{io-port 05979147} \itemau{Hungr, Nikolai; Fouard, C\'eline; Robert, Adeline; Bricault, Ivan; Cinquin, Philippe} \itemti{Interventional radiology robot for CT and MRI guided percutaneous interventions.} \itemso{Fichtinger, Gabor (ed.) et al., Medical image computing and computer-assisted intervention -- MICCAI 2011. 14th international conference, Toronto, Canada, September 18--22, 2011. Proceedings, Part I. Berlin: Springer (ISBN 978-3-642-23622-8/pbk). Lecture Notes in Computer Science 6891, 137-144 (2011).} \itemab Summary: This paper introduces a new patient-mounted CT and MRI guided interventional radiology robot for percutaneous needle interventions. The 5 DOF robot uses ultrasonic motors and pneumatics to position the needle and then insert it progressively. The needle position and inclination can be registered in the images using two strategically placed fiducials visible in both imaging modalities. A first prototype is presented and described in terms of its sterilization, CT and MRI compatibility, and precision. Tests showed that 1) it is entirely sterilizable with hydrogen peroxide gas, 2) no image artifacts or deformations are noticeable in the CT and MRI images, 3) does not affect the SNR of MR images, and 4) its mechanical error is less than 5mm. \itemrv{~} \itemcc{} \itemut{interventional radiology; robotics; CT; MRI; image-guided; ultrasonic motors; magnetic resonance compatibility; sterilization} \itemli{doi:10.1007/978-3-642-23623-5\_18} \end