High resolution photoacoustic imaging of microvasculature in normal and cancerous bladders

We explored the potential of an emerging laser-based technology, photoacoustic imaging (PAI), for bladder cancer diagnosis through high resolution imaging of microvasculature in the interior bladder tissues. Images of ex vivo canine bladders demonstrated the excellent ability of PAI to map three-dimensional microvasculature in optically scattering bladder tissues. By comparing the results from human bladder specimens affected by cancer to those from the normal control, the feasibility of PAI in differentiating malignant from benign bladder tissues was explored. The reported distinctive morphometric characteristics of tumor microvasculature can be seen in the images from cancer samples, suggesting that PAI may allow in vivo assessment of neoangiogenesis that is closely associated with bladder cancer generation and progression. By presenting subsurface morphological and physiological information in bladder tissues, PAI, when performed in a similar way to that in conventional endoscopy, provides an opportunity for improved diagnosis, staging and treatment guidance of bladder cancer.