Mieke Bus

54 Chapter 4 during diagnostic URS. 2) Carcinoma in situ (CIS) is easily missed on URS. 3) Histopathological diagnosis is often inconclusive due to small sampling. (15) Ultimately, these limitations lead to a high rate of tumor upgrading/upstaging after nephroureterectomy. (16) If knowledge about tumor grade and stage is obtained during URS, a better selection of patients eligible for endoscopic treatment is possible. Additionally, intra-operative tumor grading and staging reduces the amount of procedures and costs. OCT has the potential to provide real time information on grade and stage. We evaluated OCT in the Upper Urinary Tract in the context of the first 2 stages (stage 1 and 2a) of the IDEAL model designed for evaluating new surgical innovations (1 Innovation/Idea, 2a Development, 2b Exploration, 3 Assessment, 4 Long-term follow-up). (17, 18) Furthermore, we highlight three cases, representing three types of UTUC and compare OCT staging and grading to histopathological diagnosis. Methods From December 2011 until October 2012, we performed a prospective study in patients with clinical suspicion or follow-up of UTUC. Eight consecutive patients candidate for diagnostic URS underwent URS and OCT imaging at the operating room of our institute. The institutional Medical Ethical Committee approved this study. Informed consent was obtained from all patients. We used a commercially available C7-XR tm Intravascular Imaging System interfaced to a sin- gle-use C7 Dragonfly tm 2.7Fr (0.9 mm) Intravascular Imaging Probe (St. Jude Medical, St. Paul, Minnesota, USA) (Figure 1A). The automatic pullback system scans a longitudinal tra- jectory of 52 mm in approximately 5.2 seconds, producing a 520-frame dataset at 15μm axial resolution. Amira (Visage Imaging GmbH, Berlin, Germany) was used for visualization. The identified ureteral lesion was manually segmented and separately rendered while given a green hue.