Radiopaque Fiducials Guiding Laparoscopic Resection of Liver Tumors

Abstract

Background: Minimal invasive laparoscopic resection of liver tumors is less traumatic compared with open surgical resection and may be a better option for many patients. However, localization of intrahepatic tumors remains a challenge. Availability of hybrid operating rooms, equipped for high performance radiologic imaging, allows for new methods of surgical navigation. Methods: Twelve patients planned for laparoscopic resection of liver tumors were included. Before resection started, tumors were marked with radiopaque fiducials. Four fiducials were positioned with ultrasound within 1 cm of the tumor. Tumor and fiducials were localized with contrast enhanced cone beam computed tomography. Fluoroscopy with an overlay of cone beam computed tomography markings was projected side-by-side on the same screen as the laparoscopic view to visualize tumor location. The fiducials were eventually removed. Laparoscopic ultrasound, the standard method of localizing a tumor, was also used. The benefits of the 2 visualization methods were estimated by the operator. Procedure times, radiation doses and resection margins were recorded. Results: Fluoroscopy with radiopaque fiducials provided valuable information, complementing the laparoscopic ultrasound, particularly during the early phase of resection. In the later phase, mobilization of the tumor-containing liver segment caused significant displacement of the fluoroscopic overlay. The technique evolved during course of the study, with decreasing procedure times and radiation doses. Radical resection was achieved for all patients. Conclusions: Radiopaque fiducials and fluoroscopy can complement laparoscopic ultrasound for guiding resection of liver tumors. Combining radiologic and optical imaging in a hybrid operating suit may facilitate development of augmented reality techniques for surgical navigation.

Hybrid operating room applications for precision hepatobiliary surgery: A narrative review

“…Their method had an acceptable degree of accuracy (maximum error of 2.5 mm) in experiments using a phantom liver and was subsequently successfully applied in a laparoscopic resection of a hepatocellular carcinoma in a 50‐year‐old patient. Falkenberg et al also utilized intraoperative fluoroscopy for guidance during resection 48 . They placed radiopaque fiducials (coils and gold rods) near the tumor to help guide surgeons during resection.…”

“…Fiducials (white patches on the image) are used to accurately overlay the images. Image source 48. of this has been demonstrated in thoracic surgery for the resection and ablation of pulmonary metastases 70.…”

Leberchirurgie 4.0 - OP-Planung, Volumetrie, Navigation und Virtuelle Realität

“…Der erste Ansatz nutzt initial eine oberflächenbasierte Registrierung mittels bestimmter Landmarken oder intraoperativem Oberflächenscanning [40,41]. Ein andere Ansatz verwendet intraoperative Bildgebungen wie das Cone-Beam-CT oder den Ultraschall, um die Registrierung zu präzisieren [42,43]. Die operations-und atembedingten Deformierungen insbesondere der intrahepatischen Strukturen werden bei beiden Ansätzen mittels biomechanischer Berechnungen simuliert und auf die Simulation übertragen [44,45].…”