An ORB-SLAM3-based Approach for Surgical Navigation in Ureteroscopy

In ureteroscopy a ﬂexible ureteroscope is used to inspect the kidneys and the ureters. In this context, we investigate robotic solutions that leverage recent developments from Simultaneous Localization and Mapping (SLAM) to provide a 3D map of the organ to be explored, as well as an estimate of the pose of the ureteroscope. With this aid, the surgeon can navigate through the organ more precisely. Additionally, for the ﬁnal organ inspection, the risk of missing certain regions of the organ is minimized. In this paper we propose a visual, monocular SLAM system based on ORB-SLAM3 that is able to estimate the pose of the ureteroscope’s tip. In order to fulﬁll this task, we introduce two preprocessing steps. The ﬁrst one aims at increasing the contrast of the image and the second one helps to avoid detecting features in non-desired regions (e.g., reﬂections). Additionally, we extend ORB-SLAM3 with A-KAZE and SuperPoint features and compare their performances to ORB features. The proposed method is evaluated in two experiments. The ﬁrst experiment shows that we are able to estimate the trajectory of the ureteroscope and the map of a synthetic kidney with low errors. The second experiment shows that the method also gives promising results in cystoscopy, where we evaluated it with videos captured during a polyp removal procedure in a real bladder.