Mechanical interface device to bone structure with an integrated targeting reference, allowing for surgical device attachment

1. A device for fixation to the skull of a patient that can serve as a fiducial marker in scan guided surgical operations using a surgical instrument characterized in that the device comprises a material translucent for applied electromagnetic waves of the scan and a fiducial marker and where the device comprises means to fixate the device in a well-defined manner to the surgical instrument, wherein the means to fixate the device to the surgical instrument comprise a surface of the device and a mating surface on the surgical instrument, where one surface has protrusions that fit within indentations on the other surface, wherein the protrusions are three cylindrical pins located along a line with their axis perpendicular to a flat surface they are located on, where two pins or indentations are each located near opposite outer edges of the device and a third pin or indentation is located between outer pins and where the indentations corresponding to the pins are slots, where outer slots corresponding to the pins on the edges have the same dimension as the pin in a direction perpendicular to the line and a larger dimension in a direction along the line, the slot between the outer slots has the same dimension as the pin in a direction along the line and a larger dimension perpendicular to the line.

2. The device according to claim 1 , characterized in that the device comprises an adapter disc where a contact surface between the mating surfaces of the device and the surgical instrument is in the shape of a ring along the outer edge of the disc.

3. The device according to claim 1 , characterized in that the translucent material comprises Polyether ether ketone (PEEK) and that the scan is a magnetic resonance imaging (MRI) scan.

4. The device according to claim 1 , characterized in that the device can be fixated to the skull with bone screws that fit in sleeves that protrude from the device.

5. The device according to claim 1 , characterized in that a surface of the device fixed to the skull follows the contours of the skull at the location of that surface.

6. The device according to claim 1 , characterized in that the fiducial marker comprises a cavity in the device filled with an liquid or pasty contrast agent.

7. The device according to claim 6 , characterized in that a shape of the cavity is a triangular groove.

8. The device according to claim 1 , characterized in that the device has a hole through which the surgical instrument can operate on the skull.