I. Introduction
Endoscopic surgery of fibroids is a definitive and feasible way of therapy in symptomatic cases. Intramural fibroids located in the deep myometrium cannot be seen with the naked eye, or palpated by laparoscopic or hysteroscopic instruments [1]. In order to avoid unnecessary incisions on the uterine wall, it is important to precisely localize the fibroids pre- and intraoperatively. Augmented reality is used in more and more fields of everyday life [2]. Applying these methods can help in combining preoperative information with endoscopic video. Using MRI has already been published for this purpose [3]. However, the cost of MRI is high and availability is also limited compared to e.g. ultrasonography. As the inclusion of a cheaper and more widely available modality, in this paper we propose a novel technique. Namely, we exhibit how the preoperatively scanned, ultrasonographic data can be projected on the real-time video showing the exact location of the fibroid.