Onscreen-guided resection of extra-axial and intra-axial forebrain masses through registration of a variable-suction tissue resection device with a neuronavigation system.

Objectives: To describe a novel surgical technique in which neuronavigation is used to guide a tissue resection device during excision of forebrain masses in locations difficult to visualize optically.
Study Design: Short case series.
Animals: Six dogs and one cat with forebrain masses (five neoplastic, two nonneoplastic) undergoing excision with a novel tissue resection device and veterinary neuronavigation system.
Methods: The animals and resection instrument were coregistered to the neuronavigation system. Surgery was guided by real-time onscreen visualization of the resection instrument position relative to the preoperative MR images. Surgical outcome was evaluated by calculating residual tumor volume according to postoperative MRI.
Results: The technique was technically simple and led to the collection of diagnostic tissue samples in all cases. Postoperative MRI was available in six cases, two with gross-total resection, three with near-total resection, and one with subtotal resection.
Conclusion: Neuronavigation-guided resection of intra-axial and extra-axial brain masses with the resection device resulted in gross-total or near-total resection in five of six animals with tumors otherwise difficult to visualize. Risk of brain shift limited absolute reliance on navigation images.
Clinical Significance: Real-time neuronavigation assistance is a feasible method for guidance and successful resection of brain masses that are poorly visualized because of intra-axial or deep location, tumor appearance, or hemorrhage.
(© 2020 The American College of Veterinary Surgeons.)