Endoscopic Transcanal Approach to Lateral Skull Base Lesions

Background A majority of petrous bone and lateral skull base pathologies are benign in nature. The complex anatomy warrants an extensive approach with associated morbidity. A minimally invasive pure endoscopic transcanal approach is a better alternative approach for select lesions.

Objective To assess the surgical procedure and outcome of endoscopic technique utilized in two cases of petrous bone lesions.

Methodology Two cases of petrous bone cholesteatoma (one congenital cholesteatoma with facial palsy and one acquired cholesteatoma) were treated with transcanal transpromontorial and infracochlear approaches.

Results Complete removal of disease was achieved with minimal drilling. The operative time was ∼140 minutes. The cerebrospinal fluid (CSF) leak was controlled with fat and fascia. No CSF otorrhea was noticed in postoperative period. The average hospital was 3 and 4 days, respectively. The average blood loss was 10 mL.

Conclusion In the subset of cases with limited benign disease of petrous bone, an endoscopic transcanal approach is a better alternative to external approach. It decreases operative time, blood loss, morbidity, and hospital stay. The lack of depth perception is a major hurdle which can be overcome by experience in endoscopic middle ear surgery. The approach can create direct access to cochlea/petrous apex/IAC/suprageniculate ganglion region.