Optimizing Surgical Plans for Parenchyma-Sparing Liver Resections through Contour-Guided Resection and Surface Approximation

Objective: This study introduces a novel method for defining virtual resections in liver cancer surgery, aimed at enhancing the adaptability of parenchyma-sparing resection (PSR) plans. By comparing these with traditional anatomical resection (AR) plans, we explore the potential for optimization in surgical planning. Methods: Leveraging contours and spline surface approximations directly from the liver's surface, our method aligns closely with actual surgical procedures, offering a more realistic representation of curved resection paths. This technique, tested against 14 cases from the OSLO-COMET study, incorporates surface deformation for versatile plan modeling, comparing volumetric outcomes of PSR and AR. Results: The study highlights significant benefits of PSR over AR, including reduced resected volume ($32.71 \pm 13.80$ ml for PSR vs. $249.53 \pm 135.23$ ml for AR, $p <0.0001$) and higher remnant liver volume ($1922.77 \pm 442.86$ ml for PSR vs. $1716.87 \pm 403.00$ ml for AR, $p <0.0001$). PSR also showed a considerably higher remnant percentage ($98.16 \pm 0.81%$) compared to AR ($87.40 \pm 6.49%$, $p <0.0001$). Conclusion: The proposed approach is able to define virtual resections accommodating a wide variety of resections (i.e., PSR and AR). Careful surgical planning using virtual resections can optimize the resection strategy. Significance: This study presents a novel computer-aided planning system for liver surgery, demonstrating its efficacy and flexibility for definition of virtual resections. Virtual surgery planning can be used for optimization of resection strategies leading to increased preservation of healthy tissue.