Feasibility of intraoperative navigation to the sentinel node in the groin using preoperatively acquired single photon emission computerized tomography data: transferring functional imaging to the operating room.

Purpose: We explored the clinical feasibility and accuracy of intraoperative navigation based on preoperatively acquired 3-dimensional functional imaging data.
Materials and Methods: Ten patients with penile carcinoma scheduled for sentinel node biopsy were prospectively included in study. After tracer injection preoperative single photon emission computerized tomography/computerized tomography was performed with a reference target fixed on the patient. Repositioning a sterile reference target shortly before surgery allowed 3-dimensional single photon emission computerized tomography/computerized tomography mixed reality based navigation of the γ probe (also containing a reference target) to the sentinel node. The accuracy of the declipse®SPECT navigation approach was determined in relation to the incision site indicated by the conventional γ probe in the coronal plane and the depth estimation measured on axial computerized tomography slices in the sagittal/axial plane.
Results: The 3-dimensional mixed reality approach enabled γ probe navigation toward the sentinel node in all 10 patients. The average ± SD navigation error in the coronal and saggital/axial planes was 5.0 ± 3.9 and 5.3 ± 3.9 mm, respectively.
Conclusions: To our knowledge this is the first study demonstrating the feasibility of intraoperative navigation based on preoperatively acquired 3-dimensional single photon emission computerized tomography/computerized tomography images. Although confirmation of successful target localization (eg using γ tracing or fluorescence imaging) remains indispensable, this opens the way to translate 3-dimensional functional imaging data to the operating room.
(Copyright © 2014 American Urological Association Education and Research, Inc. Published by Elsevier Inc. All rights reserved.)