Objective
To explore a surgical technique for completing ventral bone decompression and C1–2 plate-screw fixation in the craniocervical junction (CVJ) through nasal approach by stage I at the imaging and physical anatomy levels, and to evaluate its feasibility.
Methods
Radiographic parameters of 80 patients with basilar invagination (BI) and 56 with normal CVJ anatomy were retrospectively analyzed. Three-dimensional (3D) reconstructions were performed in 31 patients with BI. Key anatomical landmarks, screw entry points, and fixation trajectories were evaluated. Customized plate-screw constructs were designed. Finally, surgical feasibility was tested on a 3D-printed anatomical model and a cadaveric.
Results
In 80 BI patients, the average distances between 4 screw insertion points were 16.04 mm, 21.10 mm, 6.83 mm, and 7.10 mm. C2 lateral mass oblique lengths were 16.81 mm (right) and 17.12 mm (left); C1 lengths were 18.71 mm (right) and 19.07 mm (left), with significant differences between C1 and C2 (p<0.001). A 28.5×14.1-mm titanium plate with 16 mm screws was successfully implanted via the nasal route in the polyether ether ketone 3D-printed BI model and the cadaveric. Radiology indicated that the screws were all in the lateral mass and the plates fit tightly.
Conclusion
In BI, transnasal odontoidectomy and plate-screw fixation of C1–2 are feasible theoretically. This may enable a new alternative approach for nasal minimally invasive decompression and immobilization, following the completion of biomechanics and clinical trials.

Objective
Endoscopic approaches to the craniovertebral junction (CVJ) have been established as viable and effective surgical treatments in the past decade. One of the major complications is leakage of the cerebrospinal fluid (CSF). This study aimed to investigate the efficacy and feasibility of suture closure at the nasopharyngeal mucosa upon durotomy.
Methods
A series of consecutive patients who underwent different endoscopic approaches to the CVJ were retrospectively reviewed. The pathologies, surgical corridors, neurological and functional outcomes, radiological evaluations, and complications were analyzed. Different strategies of repair for the intraoperative CSF leakage were described and compared.
Results
A total of 22 patients covering 13 years were analyzed. There were 12, 2, and 8 patients who underwent transnasal, transoral, and combined approaches, respectively. There were 8 patients (36.4%) who experienced intraoperative CSF leakage, and were grouped into 2: 4 in the nonsuture (NS) group and 4 in the suture-repaired (SR) group. The NS group had 3 (75%) persistent CSF leakages postoperation that caused 1 mortality, whereas patients of the SR group had only 1 minor CSF rhinorrhea that healed spontaneously within days.
Conclusion
In this series of 22 patients who required anterior endoscopic resection of pathologies at the CVJ, there was 1 (4.5%) serious complication related to CSF leakage. For patients who had no durotomy, the mucosal incision at the nasopharynx usually healed rapidly and there were few procedure-related complications. For patients with intraoperative CSF leakage, suture closure was technically challenging but could significantly lower the risks of postoperative complications.