The idea of Minimally Invasive Surgery is to reduce the trauma for the patient by minimizing incisions and tissue retraction. Despite the improvement in outcomes, these techniques have their limitations and come at a cost to the surgeons. In particular, the lack of depth in perception and the difficulty in estimating the distance of the specific structures in laparoscopic surgery can impose limits on delicate dissection or suturing.

Augmented Reality technology has the potential to bring back the direct visualization advantage of open surgery to minimally invasive surgery and can increase the physician’s view with information gathered from patient medical images. In this work an Augmented Reality system has been developed where the position of the surgical instrument is detected by means of an optical tracker and this information is used to measure the distance between this instrument and the anatomical structures concerned. In addition, the system is able to warn the surgeon of possible contact with other organs located close to the organ of interest, using both visual and audio aids.