Whether cross-polarization (CP) optical coherence tomography (OCT) could be used to detect early bladder cancer was ascertained; it was compared with traditional OCT within the framework of blind (closed) clinical statistical studies. One hundred and sixteen patients with local nonexophytic (flat) pathological processes of the bladder were examined; 360 CP OCT images were obtained and analyzed. The study used an OCT 1300-U CP optical coherence tomographer. CP OCT showed a high (94%) sensitivity and a high (84%) specificity in the identification of suspected nonexophytic areas in the urinary bladder.</p