Calculating a guaranteed zone of foramen ovale cannulation: a technical note with implications for trigeminal neuralgia


  • Chad A Kuhns Dept of Natural Sciences & Mathematics at West Liberty University
  • Matthew J Zdilla West Liberty University; West Virginia University School of Medicine



cranial base, neuronavigation, neurosurgery, stereotaxic techniques, trigeminal neuralgia


Cannulation of the foramen ovale is often performed for treatment of trigeminal neuralgia. Despite advances in resolution and visualization, fluoroscopy and computed tomography paired with navigation technology have proven unsuccessful in cannulating the foramen. Therefore, approaches to foramen ovale cannulation warrant improvement. This study applies a geometric model to analyze the region of a foramen occupied by a cylindrical surgical tool (e.g., a cannula, stylet, catheter, or needle) inserted at an angle (ϕ) to the plane of the foramen. As the tool passes through the plane of the foramen, its cross-section is an ellipse with a major axis depending on ϕ. Accordingly, the area of the region depends on ϕ, as well as on the radius of the surgical tool. Knowing the area of the region provides a means of comparing a candidate surgical instrument to the foramen it will cannulate when the area of the foramen is known (e.g., as determined from imaging). After accounting for irregularities in the boundary of the foramen, the angle of approach ϕ, and relative orientations of the foramen and the elliptical region occupied by the tool, the geometric model proceeds to describe two new regions: one which guarantees successful cannulation and one which guarantees the tool will not cannulate. The technique predicts when cannulation of a foramen will likely be impossible. Therefore, this method may prevent adverse surgical events and improve the surgical approach and outcomes in the treatment of trigeminal neuralgia.

Author Biographies

Chad A Kuhns, Dept of Natural Sciences & Mathematics at West Liberty University

Assistant Professor of Mathematics in the Dept. of Natural Sciences & Mathematics at West Liberty University

Matthew J Zdilla, West Liberty University; West Virginia University School of Medicine

Associate Professor of Biology and Physician Assistant Sciences in the Depts. of Natural Sciences & Mathematics and Graduate Health Sciences at West Liberty University. Consultant in the Department of Pathology, Anatomy, and Laboratory Medicine at West Virginia University School of Medicine


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How to Cite

Kuhns, C. A., & Zdilla, M. J. (2019). Calculating a guaranteed zone of foramen ovale cannulation: a technical note with implications for trigeminal neuralgia. Proceedings of the West Virginia Academy of Science, 91(2).



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