This study evaluates the accuracy of Confocal Laser Endomicroscopy (CLE) in the diagnostic of non-invasive flat and exophytic bladder neoplasia. CLE results are compared to histopathology results.

Confocal Laser Endomicroscopy (CLE) is a technique which during endoscopic examination of the bladder (cystoscopy) gives magnified, microscopic-like images of tissues and cells, by inserting a laser fiber through the cystoscope. CLE aims to target biopsies during cystoscopy and reduce the number of biopsies, and the need for additional cystoscopies i general anesthesia.

This study evaluates the ability of CLE to assess tissue in the bladder. The ability to diagnose normal mucosa, inflammation and tumors of the bladder by the CLE is compared to the histopathological examination of selected tissues (biopsies).

Patients scheduled for cystoscopy with biopsies in general anesthesia are recruited for the study. After standard cystoscopy where suspicious mucosal areas are located and marked, A contrast agent (Fluorescein) is administrated intravenously. CLE fiber is introduced through the cystoscope and the marked mucosal areas are examined by direct contact with the laser fiber. The pathologist assesses the CLE video and registers the results. Biopsies are then taken from the selected, suspicious areas. The results of CLE assessment are compared with the histopathological results.

Inclusion Criteria:

• First time Transurethral Resection of Bladder (TURB) for bladder tumors under 3 cm
• Suspicious mucosa / Carcinoma in situ
• Recurrent pTa
• Positive cytology with normal flexible cystoscopy
• Control after Bacille Calmette Guérin (BCG) treatment

Exclusion Criteria:

• Allergy to fluorescein
• Pregnant and lactating women.
• Renal failure (eGFR <20 ml / min)