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C1 and C2 nerve sheath tumors: analysis of 32 cases.

BACKGROUND
C1 and C2 nerve sheath tumors are to be considered as a separate clinical entity because of their unique clinical presentation, relation to the adjacent structures and surgical approaches when compared to their counterparts in other regions.


AIM
To present the clinical characteristics, radiological findings, operative approaches, and outcomes.


SETTING AND DESIGN
Of the 32 patients, the study was retrospective in 22 patients and in 10 it was prospective.


MATERIALS AND METHODS
Patients' case records were analyzed. Diagnosis was established by magnetic resonance imaging of craniovertebral junction. Patients were evaluated by Yasargil grading and operative procedure was done accordingly.


RESULTS
In this series the tumors were multiple and had extradural extension and hourglass expansion. Surgical results were excellent in most patients when procedure was done early in the course of the disease. Best results in terms of complete removal and good neurological outcome were achieved with posterior or posterolaterlly located lesion. Of the 20 patients who had surgery by posterior approach, 19 (95%) patients had improvement postoperatively, while one (5%) patient remained unchanged. While of the 8 patients who had surgery by posterolateral approach, 6 (75%) had improvement postoperatively, one had no change and the other had neurological deterioration.


CONCLUSION
C 1 and C 2 nerve sheath tumors are to be considered as a separate clinical entity. Operative results and recovery of patients are excellent when tumor is located posterior or posterolaterally and surgical procedure is done early in the disease course.