Functional intra-operative guidance of the cavernous nerve network using near-infrared cyanine voltage-sensitive dye imaging: relevance for nerve-sparing radical prostatectomy

Despite current progress achieved in the surgical technique of radical prostatectomy, post-operative complications such as erectile dysfunction and urinary incontinence persist at high incidence rates. In this paper, we present a functional intra-operative guidance of the cavernous nerve (CN) network for nerve-sparing radical prostatectomy using near-infrared cyanine voltage-sensitive dye (VSD) imaging, which visualizes membrane potential variations in the CN and its branches (CNB) in real time. As a proof-of-concept experiment, we demonstrated a functioning complex nerve network in response to electrical stimulation of the CN, which was clearly differentiated from surrounding tissues in an in vivo rat prostate model. Stimulation of erection was confirmed by correlative intracavernosal pressure (ICP) monitoring. Within 10 min we performed trans-fascial staining of the CN by direct VSD administration. Our findings suggest the applicability of VSD imaging for nerve-sparing radical prostatectomy.