Image-guided surgery (IGS) lets a surgeon track the position of implants and instruments in a virtual-reality display relative to the patient's anatomy. The aim is to guide the device safely and precisely to its target in three dimensions - and to reduce the invasiveness of procedures to a minimum. For example, navigated otolaryngologic surgery makes it easier to perform complicated sinus and temporal bone surgeries. Navigated orthopedic surgery ensures that an implant is precisely positioned. Its use in other surgical specialties is being evaluated. Here's what you need to consider when deciding whether to invest in IGS equipment. Assess the clinical benefits.