Microscopic Transoral versus Endoscopic Endonasal Approach to the Craniocervical Junction

Abstract

Introduction Odontoidectomy represents the treatment of choice in case of irreducible atlanto–axial dislocation with compression of the ventral spinal cord. The transoral–transpharyngeal approach represents the gold standard and more commonly used technique. The endoscopic endonasal approach represents a new technique that provides direct, minimal access to the odontoid process. Materials and Methods We reviewed our experience with both techniques (47 transoral, 6 transnasal), analyzing technical factors, intraoperative nuances, caveats and complications, and functional outcomes. Results Endoscopic endonasal odontoidectomy proved to be a safe, effective, and well-tolerated procedure. Anatomically, there is considerable overlap at the pharyngeal level in the structures that can be viewed by the transoral and transnasal routes. The transoral approach provides a wider corridor with less restricted manipulation of instruments than the transnasal approach, but the transnasal approach provides a better view of the clivus, upper part of the craniovertebral junction, and the structures posterior to the removed odontoid and anterior arch of C1. Conclusion The two different approaches for odontoidectomy should be considered complementary rather than strict alternatives: the endonasal endoscopic can be advantageous in selected cases, presenting some anatomical conditions related to the oral cavity (micrognathia and macroglossia) and to high position of the odontoid. Combined approaches can also become necessary in particular cases. Careful patient selection and preoperative surgical planning is critical to obtaining satisfactory removal and low rate of postoperative complications.