Individualized Treatment of Craniovertebral Junction Malformation Guided by Intraoperative Computed Tomography

Study Design: This study was designed to report our preliminary experience of intraoperative computed tomography (iCT) using a mobile scanner with integrated neuronavigation system (NNS). Objective: The objective of this study was to assess the feasibility and potential utility of iCT with integrated NNS in individualized treatment of craniovertebral junction malformation (CVJM). Summary of Background Data: The surgical management of congenital craniovertebral anomalies is complex due to the relative difficulty in accessing the region, critical relationships of neurovascular structures, and the intricate biomechanical issues involved. Methods: We reported our first 19 complex CVJM cases including 11 male and 8 female patients from January, 2009 to June, 2009 (mean age, 33.9 y; age range, 13 to 58 y). A sliding gantry 40-slice CT scanner was installed in a preexisting operating room. Image data was transferred directly from the scanner into the NNS using an automated registration system. We applied this technology to transoral odontoidectomy in 17 patients. Moreover, with the extra help of iCT integrated with NNS, odontoidectomy through posterior midline approach, and transoral atlantal lateral mass resection were, for the first time, performed for treatment of complex CVJM. Results: NNS was found to correlate well with the intraoperative findings, and the recalibration was uneven in all cases with an accuracy of 1.6mm (1.6: 1.2 to 2.0). All patients were clinically evaluated by Nurick grade criteria, and neurological deficits were monitored after 3 months of surgery. Fifteen patients (79%) were improved by at least 1 Nurick grade, whereas the grade did not change in 4 patients (21%). Conclusions: iCT scanning with integrated NNS was both feasible and beneficial for the surgical management of complex CVJM. In this unusual patient population, the technique seemed to be valuable in negotiating complex anatomy and achieving a safe and predictable decompression.