Time-gated optical imaging to detect positive prostate cancer margins

Abstract

Laparoscopic radical prostatectomy (LRP) has revolutionized the surgical treatment of prostate cancer. This procedure permits complete removal of the prostate and seminal vesicles while minimizing pain and recovery time. However, the laparoscopic approach greatly limits the surgeon's tactile sensation during the procedure. This is particularly true with robot-assisted LRP where no tactile feedback is available forcing the surgeon to rely solely on visual cues. The surgeon and pathologist perform intraoperative frozen section pathologic analysis of a few select tissue fragments, but this is time consuming and costly. Concrete conclusions based on such samples are unreliable as they do not reflect the entire surgical margin status. In this case a conservative approach might dictate removal of more marginal material than necessary, thereby compromising the important nerve-sparing aspects of the procedure. In this study, we demonstrate the feasibility of using multi-modal time-gated optical imaging, i.e. time-resolved light reflectance and auto-fluorescence life-time imaging performed by an ICCD (Intensified Charge-Coupled Device) imaging system to enable clinicians to detect positive tumor margins with high sensitivity and specificity over the prostate. Results from animal experiments present the potential of identifying differences in optical signals between prostate cancer and control tissues. Results also show that the use of classification algorithms can identify cancerous regions with high sensitivity and specificity.