Is naso-axial line a better predictor in endoscopic endonasal resection of the odontoid and pannus removal? Technical nuances of maximizing corridor and maintaining occipital cervical joint stability.

BACKGROUND: The transoral transpharyngeal odontoidectomy, followed by occipitocervical fixation, have traditionally been a recognized method for ameliorating ventral compression at the craniovertebral junction (CVJ), despite its associated comorbidities. As an alternative, the endoscopic endonasal odontoid resection is a viable approach for various CVJ abnromalities that preserve the oropharynx and leads to fewer procedure-related complications(1-4). We present our case to detail the technical nuances of the procedure and its advantages over other techniques.

CASE DESCRIPTION: In this video, we describe our experience of a novel modified endoscopic endonasal odontoidectomy (EEO) for the removal of a large retro-odontoid pannus, compressing the spinal cord at the level of CVJ. The patient is a 73-year-old male presenting with progressive bilateral myelopathic symptoms. There was significant clinical improvement postoperatively, and C1-C3 fixation was performed. An MRI at two months later showed an adequate ventral decompression and normal spinal cord shape at the level of CVJ.

CONCLUSION: The endoscopic endonasal approach to the odontoid process offers a less invasive alternative to other methods, which may reduce patient discomfort during and after surgery. By avoiding disruption of the oropharynx, this method can significantly lower the risk of complications such as surgical site infection and poor healing associated with the surgical approach. This technique is advisable for carefully selected patients with favorable sinonasal anatomy. The nasal axial line can more accurately predict the inferior border of the odontoid resection during preoperative planning and intraoperative neuronavigation. It guides the lower extent of odontoidectomy that is affordable by endoscopic endonasal approach.