4D Ultrasound Cistoscopy with Fly through in the evaluation of Urinary Bladder tumors: Feasibility and Outcomes.

Introduction & Objectives Cystoscopy represents the gold standard method both for the diagnosis and the surveillance of patients treated conservatively for bladder cancer. To date, a reliable, non-invasive, imaging method for bladder cancer detection has yet to be established and follow-up is, therefore, based on regular cystoscopy. The recently introduced Fly Thru technology virtually travel through a body cavity and produces endoscopic images from outside the body. This provides the opportunity to assess masses and plan for appropriate management. Objective of this study is to assess the feasibility and diagnostic efficacy of 4D Ultrasound cystoscopy with Fly through as compared with traditional 2D US and cystoscopy in detecting and characterizing urinary bladder lesions. Materials & Methods Between August 2016 and July 2017, 30 consecutive patients with bladder lesions previously detected at cystoscopy were prospectively evaluated with 2D baseline Ultrasound and 4D Ultrasound with fly through (US virtual navigation system) by an expert radiologist blinded to cystoscopy results. The two imaging modalities were compared with cystoscopy in order to assess the sensitivity and specificity in tumour detection and characterization. The diagnostic performance of 2D features and 4D Ultrasound were estimated and compared using ROC curve analysis. Results In total, 24/33 (73%) and 31/33 (94%) urinary bladder lesions were detected by 2 D Ultrasound and 4 D Ultrasound, respectively. In addition, the 4 D Ultrasound was also able to identify two more lesions that had not been detected by previous traditional cystoscopy. Additionally, tumour features at ultrasound were consistent with those provided by the cystoscopy, with no significant differences in terms of characterization (p=0.865). Conclusions Our preliminary results show that 4 D Ultrasound cystoscopy with fly through is more accurate than baseline 2D Ultrasound to detect and characterize urinary bladder lesions with similar results when compared with traditional cystoscopy.