Clinical Utility of a 3D-Printed Patient-Specific Surgical Guide for Partial Nephrectomy.

Partial nephrectomy (PN) is a common surgery for small renal masses. The goal is to remove the mass completely while preserving renal function. A precise incision is, therefore, important. However, no specific method for surgical incision in PN exists, although there are several guides for bony structures using three-dimensional (3D) printing methods. Therefore, we tested the 3D printing method to create a surgical guide for PN. We describe the workflow to make the guide, which comprises computed tomography data acquisition and segmentation, incision line creation, surgical guide design, and its use during surgery. The guide was designed with a mesh structure that could be fixed to the renal parenchyma, indicating the projected incision line. During the operation, the 3D-printed surgical guide accurately indicated the incision line, without distortion. An intraoperative sonography was performed to locate the renal mass, which confirmed that the guide was well placed. The mass was completely removed, and the surgical margin was negative. No inflammation or immune reaction occurred during and 1 month after the operation. This surgical guide proved useful during PN for indicating the incision line and was easy to handle, without complications. We, therefore, recommend this tool for PN with improved surgical outcome.