Theranostics 2017; 7(3):573-593. doi:10.7150/thno.17433

Research Paper

Direct Administration of Nerve-Specific Contrast to Improve Nerve Sparing Radical Prostatectomy

Connor W. Barth1, Summer L. Gibbs1,2,3✉

1. Biomedical Engineering Department, Oregon Health & Science University, Portland, OR 97201.
2. Knight Cancer Institute, Oregon Health & Science University, Portland, OR 97201.
3. OHSU Center for Spatial Systems Biomedicine, Oregon Health & Science University, Portland, OR 97201.

Abstract

Nerve damage remains a major morbidity following nerve sparing radical prostatectomy, significantly affecting quality of life post-surgery. Nerve-specific fluorescence guided surgery offers a potential solution by enhancing nerve visualization intraoperatively. However, the prostate is highly innervated and only the cavernous nerve structures require preservation to maintain continence and potency. Systemic administration of a nerve-specific fluorophore would lower nerve signal to background ratio (SBR) in vital nerve structures, making them difficult to distinguish from all nervous tissue in the pelvic region. A direct administration methodology to enable selective nerve highlighting for enhanced nerve SBR in a specific nerve structure has been developed herein. The direct administration methodology demonstrated equivalent nerve-specific contrast to systemic administration at optimal exposure times. However, the direct administration methodology provided a brighter fluorescent nerve signal, facilitating nerve-specific fluorescence imaging at video rate, which was not possible following systemic administration. Additionally, the direct administration methodology required a significantly lower fluorophore dose than systemic administration, that when scaled to a human dose falls within the microdosing range. Furthermore, a dual fluorophore tissue staining method was developed that alleviates fluorescence background signal from adipose tissue accumulation using a spectrally distinct adipose tissue specific fluorophore. These results validate the use of the direct administration methodology for specific nerve visualization with fluorescence image-guided surgery, which would improve vital nerve structure identification and visualization during nerve sparing radical prostatectomy.

Keywords: nerve sparing radical prostatectomy, fluorescence image-guided surgery, nerve-specific fluorophore, prostate cancer, direct administration.

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How to cite this article:
Barth CW, Gibbs SL. Direct Administration of Nerve-Specific Contrast to Improve Nerve Sparing Radical Prostatectomy. Theranostics 2017; 7(3):573-593. doi:10.7150/thno.17433. Available from http://www.thno.org/v07p0573.htm