Optical Coherence Tomography of Cavernous Nerves: A Step Toward Real-Time Intraoperative Imaging During Nerve-Sparing Radical Prostatectomy
Received 25 August 2007; accepted 16 November 2007. published online 18 February 2008.
Objectives
To demonstrate the use of optical coherence tomography (OCT) for imaging of the cavernous nerve (CN) and periprostatic tissues. The rates of nerve preservation and postoperative potency after radical prostatectomy might improve with better identification of the CN using emerging intraoperative imaging modalities. OCT is an imaging modality that allows for real-time, high-resolution, cross-sectional imaging of tissues.
Methods
Seven male Sprague-Dawley rats underwent surgery using a midline celiotomy to expose the bladder, prostate, and seminal vesicles. The CNs and major pelvic ganglion were identified. Visual identification of the CN was further confirmed by electrical stimulation with simultaneous intracorporeal pressure measurements. OCT images of the CN, major pelvic ganglion, bladder, prostate, and seminal vesicles were acquired and correlated directly with the histologic findings. Once a baseline technique for the scanning and interpretation of the acquired images was established using the rat model, OCT was used to image ex vivo human prostatectomy specimens.
Results
OCT provided unique imaging characteristics, differentiating the CN from the bladder, prostate, seminal vesicles, and periprostatic fat. OCT images of the CN and prostate correlated well with the histologic findings. OCT of ex vivo human prostatectomy specimens revealed findings similar to those with the rat experiments, with, however, less dramatic architecture visualized in part because of the thicker capsule and more dense stroma of human prostates.
Conclusions
The results of our study have shown that OCT provides real-time, high-resolution imaging of the CN in the rat model with excellent correlation to the histologic findings. This study provides a basis for the intraoperative use of this emerging technology during nerve-sparing prostatectomy.
aJames Buchanan Brady Urological Institute, Johns Hopkins Medical Institutions, Bethesda, Maryland
cDepartment of Pathology, Johns Hopkins Medical Institutions, Bethesda, Maryland
bDepartment of Physics and Optical Science, University of North Carolina at Charlotte, Charlotte, North Carolina
Reprint requests: Li-Ming Su, M.D., Department of Urology, Division of Laparoscopic and Robotic Surgery, James Buchanan Brady Urological Institute, Johns Hopkins Medical Institutions, Jefferson Street Building, Suite 161, 600 North Wolfe Street, Baltimore, MD 21287.
ABSTRACT