necessary with ionising radiation modalities such as fluoroscopy, CT, X-Ray and tomography. Optical topographic imaging using structured light and machine vision stereoscopic cameras has been applied in neurosurgical navigation systems to reduce the use of intraoperative ionising radiation as well. Modern image-guided surgery systems are often combined with robotics. Neurosurgery The various applications of navigation for neurosurgery have been widely used and reported for almost two decades. According to a study in 2000, researchers were already anticipating that a significant portion of neurosurgery would be performed using computer-based interventions. Recent advancements in ultrasound, including intravascular ultrasound (IVUS) allow for real-time cross sectional mapping of vessels and lateral tissues providing calibrated measurements of vessel diameters, contours and morphology. Image-guided surgery was originally developed for treatment of brain tumors using stereotactic surgery and radiosurgery that are guided by computed tomography (CT), magnetic resonance imaging (MRI) and positron emission tomography (PET) via technologies such as the N-localizer and Sturm-Pastyr localizer. Image-guided surgery systems are also used in spine surgery to guide the placement of implants and avoid damaging the nearby neurovascular structures. Orthopedics A mini-optical navigation system has been developed that makes real-time measurements to guide surgeons during total hip arthroplasty procedures. This image-guide surgery system involves a patient-mounted camera and a tracker for positional detection by the camera when mounted on surgical instruments or anatomical locations. Urology Image-guided surgery based on MRI is used to guide prostatic biopsy. Image guidance is used to assist surgeons with identifying anatomic landmarks and surgical planes between the prostate and neurovascular bundles during nerve-sparing procedures. This can help reduce negative effects of the procedure like sexual dysfunction and urinary incontinence. See also Computer assisted surgery Interventional radiology Intraoperative MRI Microsoft Hololens Radiosurgery Stereotactic surgery References Further reading Computer-assisted surgery