Steen M Hansen, MD1, Michael S Hansen2, Peter Funch-Jensen, MD, DMSc, Professor3. 1Aalborg University Hospital, 2Vrinno, 3Department of Clinical Medicine, Aarhus University
Objective: No at-hand real-time volumetric measuring methods are currently available for laparoscopic surgery. Such measures would enable the laparoscopic surgeon to quantify anatomic structures, e.g. estimating gastric pouch and sleeve sizes during bariatric operations, abdominal organ measures, as well as measuring tumor sizes during operations We present a novel method where coded structured light is utilized to construct a highly accurate real-time 3D point cloud to estimate volumetric measures of abdominal structures.
Method: A low-cost miniature projector probe (Ø 1.6mm) was constructed and integrated with a 3mm laparoscopic instrument. The prototype probe contained a customized diffractive optical element designed to project a coded structured light pattern. The probe was inserted in a surgical field and the light pattern was projected on the surgical surface. Using a commercially available laparoscopic camera, our system extracted data from the images of the coded structured light pattern. We developed a set of algorithms that used the extracted image data to calculate the probe location without the use of markers. The position data was used to construct a highly accurate and robust 3D point cloud of the illuminated anatomic structure, e.g the gastric pouch using wide-baseline 3D reconstruction techniques. In an experimental validation setup, the volume of a cubic phantom object was estimated using a geometric cubic model assumption.
Preliminary results: In an experimental validation setup, the 3D surface of a phantom surgical target was reconstructed with a 0.10mm accuracy using the miniature projector. The measurement was done in real-time. Estimating the volume of a cubic phantom object (8cm3) using the 3D reconstruction data and a cubic model assumption the calculated volumetric estimate was within an accuracy of 0.25cm3.
Conclusions and future directions: We present a novel technology where coded structured light is used for accurate 3D reconstruction of anatomic structures during laparoscopic surgery. The 3D reconstruction can be used for real-time volumetric measures. Further, the data can in the future be used to identify abdominal organs and used as a platform for image fusion and augmented reality with requirement of high precision reconstructions. In-vivo tests in animal models will be completed primo 2017.
Presented at the SAGES 2017 Annual Meeting in Houston, TX.
Abstract ID: 84445
Program Number: ETP740
Presentation Session: Emerging Technology Poster
Presentation Type: Poster