Endoscope and image-guided ventral bulla osteotomy in the dog: a cadaveric and patient study

Background: Surgery of the bulla in the dog can be difficult, and is associated with suboptimal resolution of disease and risk of complications, particularly in treatment of cholesteatoma. We explored use of image guidance and endoscopic assistance in ventral bulla osteotomy, initially with cadaveric studies and subsequently on dogs with cholesteatoma. Methods: For surgical approach we used cone beam CT with an optical image navigation system. For endoscopic surgery we used endoscopes and a camera viewing system with micro-instruments for dissection. Results: Image guidance allowed us to accurately identify and approach the bulla in cadavers (n=2) and patients (n=2). The endoscope enabled us to define detailed endoscopic anatomy in cadaveric canine heads (n=15), and in patients (n=5) it enabled reliable and safe removal of pathological tissue. Conclusion: Image and endoscopic assistance could be a significant advance to the reliability and safety of ventral bulla osteotomy. Our techniques may be applicable to other indications and species.