Intra-operative wearable visualization in spine surgery: past, present, and future

The history of modern surgery has run parallel to the invention and development of intra-operative visualization techniques. The first operating room, built in 1804 at Pennsylvania Hospital, demonstrates this principle: illumination of the surgical field by the Sun through an overhead skylight allowed surgeries to proceed even prior to the invention of anesthesia or sterile technique. Surgeries were restricted to begin around when the Sun was at its zenith; without adequate light from the Sun and skylight, surgeons were unable to achieve adequate visualization. In the years since, new visualization instruments have expanded the scope and success of surgical intervention. Spine surgery in particular has benefited greatly from improved visualization technologies, due to the complex and intricate nervous, vascular and musculoskeletal structures that are closely intertwined which surgeons must manipulate. Over time, new technologies have also advanced to take up smaller footprints, leading to the rise of wearable tools that surgeons don intra-operatively to better visualize the surgical field. As surgical techniques shift to more minimally invasive methods, reliable, fidelitous, and ergonomic wearables are of growing importance. Here, we discuss the past and present of wearable visualization tools, from the first surgical loupes to cutting-edge augmented reality (AR) goggles, and comment on how emerging innovations will continue to revolutionize spine surgery.