Abstract: A method for performing radiological-image-guided percutaneous surgery with a system which includes a radiological image generating device for generating an image of a target anatomy of a patient, and a needle insertion mechanism disposed adjacent the image generating device and having a needle adapted to be inserted into the patient. The method includes the steps of: determining a needle trajectory of the needle by positioning the image generating device for aligning, in the image generated by the image generating device, a desired skin insertion site of the patient with a target region of the target anatomy; locking the needle in a direction of the needle trajectory; and repositioning the image generating device to obtain a lateral view of the needle trajectory for viewing an insertion depth and path of the needle during its insertion into the patient.